Quantcast
Channel: Biotechnology Forums - All Forums
Viewing all 2695 articles
Browse latest View live

"Making Organs In Bioreactors" : An Insight

0
0
ORGANS IN BIOREACTORS!:
Ever imagined the production of fully-functional organs in Bioreactors? And, not only this! their successful transplantation in the target organism?! Well, if not, then the research by Dr. Harold C Ott of Harvard Medical School, Boston, Massachusetts, USA published in The Nature Medicine, on April 14, 2013, should not only make you imagine so, but believe too!

Dr. Harold's lab works on in-vitro synthesis of new organs for living organisms, but with a distinct approach. Rather than de-novo synthesis of the entire organ from the totipotent cells in animal cell-culture facility (which hasn't resulted in any fully-functional and organized organ till date), his approach is to use the target organism's organ itself as the base for initiating the organ-culture.

The Ideal Approach:
The organ to be changed is taken out of the organism. It is stripped off all the cells/tissue matter inside using a mild detergent solution (process called De-cellularization). What's left behind is a scaffold of the organ (sort of a mould, made of the basic connective tissue required for the structural organization of the organ). The scaffold is then supplied with the embryonic cells for the organ/endothelium from the young organism of preferably same species (preferably, a close relative). A pressure gradient is applied to the scaffold to ensure the retention of the cells in the scaffold. The scaffold is kept in a perfusion bioreactor with the requisite media and allowed to differentiate into a fully/partially functional organ. The organ is then transplanted into the target organism and checked for the functional characteristics. This is the way Harold's approach should work ideally in near future, as explained by Dr. Harold C Ott in this Nature Video!:




Following is the step wise insight into the actual research done by Harold and team on synthesizing a "kidney" in the lab in a bioreactor, which was later transplanted successfully in a rat.

1. Cadaveric (dead) Rat Kidneys were obtained.

2. They were de-cellularized by renal artery perfusion using mild SDS, deionized water and Triton X-100 solution (detergent) at a low constant pressure (around 40 mm Hg), so that the organ might not burst/collapse.

3. Scaffolding preserved the tissue architecture, but removed all cells/nuclei. Vascular, cortical and medullary architecture, a collecting system and ureters were retained in the scaffold.

4. Preservation of the basic architecture was very important as the key processes of filtration (glomerular basement membrane), secretion and reabsorption (tubular basement membrane) require the highly organized structural framework.

5. Washing with PBS was done to remove the traces of detergent.

6. Regeneration of kidney tissue was attempted by repopulating the scaffold with endothelial and epithelial cells. Human umbilical venous endothelial cells (HUVECs) and Rat neonatal kidney cells (NKCs) were perfused through the scaffold using 40cm H20 pressure gradient. Maintenance of the pressure was cruacial for retaining the cells in the scaffold, without damage/leaking of the cells.

7. The seeded scaffold was then transferred to a perfusion bioreactor having optimal organ-culture conditions and nutrient media.

8. HUVECs lining of the vasculature in the entire scaffold was observed in 3-5 days of bioreactor inoculation.

9. As the NKCs were obtained from neonatal rats, maturation signals such as glucocorticoids and catecholamines were supplied in the media for differentiation of the tubular apparatus to produce concentrated urine.
Histologic evaluation after within 4 days indicated epithelial and endothelial cells repopulated on the scaffold without any damage to the glomerular, tubular and vascular architecture. The optimal usage of the pressure gradient enabled proper engrafting of the NKCs and HUVECs at the vascular/epithelial compartments they were meant for in the normal organ. Nephrons' microanatomy was established in the culturing organ, laying the foundation for the basic functions of filtration, secretion, absorption and urine production. Non-specific grafting wasn't observed during immunostaining, which was a positive signal towards proper differentiation.

10. Overall, a 12 day culture resulted in partially functional organ.

11. After the culture, Orthotopic (at the normal place, where it's meant to be) transplantation of the lab-generated kidney was done. No-bleeding/blood leakage was observed in the vasculature of the regenerated kidney. Urine was continously produced with clearance of metabolites till experimental observation without any clotting either.

12. The quality of urine matched the quality produced during in-vitro observations (with glucose, albumins, urea, creatinine etc in same concentration as in-vitro, though much higher than the actual physiological requirement).

Conclusion:
Though, lot needs to be done, this approach of Dr. Harold and team, has highlighted an altogether a new way and hope for meeting the needs of millions of organ transplant seekers across the globe (especially the kidney transplant seekers). Considering the immediate functioning of the regenerated kidneys after transplant, this approach seems highly promising, especially considering the fact that even 'cadaveric' kidneys can act as the source of the scaffold. Optimization of cell seeding strategies, isolation, differentiation and expansion of the required cell types from clinically feasible sources and upscaling of the biomimetic organ culture is what Dr. Harold's team believes may pave the way for in-vitro production of fully-functional organs!

Harold's research is not limited to a particular organ, rather his team has been working on a lot of organs including heart and lungs (as you might have seen in the video). In fact, this research was motivated by the successful attempts in scaffolding of heart and lungs ECM by his (and other) teams. So, let's hope that this research treads fast on the right path towards providing a radical new way of bringing an end to the long wait of the patients looking for an organ donor and save his/her life!

Thanks

Can Bacteria Control Obesity and Diabetes?

0
0
Excess Body Fat? Bacteria may be the remedy!

A group of scientists predicts that there may be a possibility of using the common gut inhabitant Akkermansia muciniphila, a Gram negative bacterial species living in large numbers in the intestinal mucus layer of humans, for developing a treatment for obesity and type-2 diabetes. Their research, published in the journal Proceedings of the National Academy of Sciences in May 2013, confirms that A. muciniphila can actually reduce obesity (genetic and diet-induced) in mice. It was also observed that plasma glucose levels of the mice were reduced significantly after oral administration of the bacterium.

Obesity and Type 2 diabetes

Obesity, defined by the WHO as the excessive accumulation of fat within the body up to the levels that presents a health risk, is recognized as a leading preventable cause of death all over the world. A person with a body mass index (BMI) of 30 or more is generally considered obese. Obesity is the cause of a number of persistent diseases, such as diabetes, cardiovascular diseases and some cancers. Obesity is usually diet-induced although genetics may also be a key to the disease in some individuals.

Type 2 diabetes (non-insulin-dependent diabetes) results from the body’s ineffective use of insulin. Diabetes may lead to many disorders including cardiovascular diseases, foot ulcers, blindness and kidney failure.

Obesity and Type-2 diabetes are often interlinked. The conditions such as gut barrier disruption, gut inflammation, metabolic endotoxemia and alteration of gut microbial population are often considered as characteristics of obesity and type 2 diabetes.

Some gut flora can make you fat

Effect of intestinal flora on obesity and its related disorders is of great interest to the researchers throughout the world. Previous literature suggest that gut microbiota, helping to break down otherwise indigestible foods increase the amount of energy extracted from the diet, thus leading to obesity. One such study, published in the journal Proceedings of the National Academy of Science in November 2004, reports that upon introducing gut microbiota from normal mice into germ-free recipients, a rapid increase in body fat content in those mice was observed even without any increase in food consumption.

On the contrary…

This research, however, presents contrasting evidence that the normal gut inhabitant, Akkermansia muciniphila is associated with reducing both diet-induced and hereditary obesity. This bacterium makes up 3–5% of the intestinal microflora of healthy human and its numbers exhibit inverse correlation with body weight of humans and mice.

The study demonstrated that the abundance of the said bacterium greatly reduced in genetically and diet-induced obese mice. Furthermore, when the mice were fed oligofructose as a prebiotic, the levels of the bacterium in the gut were restored completely, in turn resulting in the elimination of metabolic endotoxemia, reduction of the total fat mass and decrease in body weight of those mice. Although the exact mechanism by which the oligofructose supports the bacterial growth is yet to be explained, these results support the fact that the bacterium A. muciniphila plays a key function in controlling the obesity.

This study also reveals that oral administration of viable A. muciniphila cells to a population of mice which were fed a high-fat diet reversed diet-induced disorders such as endotoxemia, obesity and hyperglycemia. There was also a significant reduction in body weight and insulin resistance index of the mice. These effects could not be reproduced when the mice were fed heat-treated bacterial cells.

The effects of administration of the bacterium in humans are yet to be established through human clinical studies. Nevertheless, this research lays the foundation for using the bacterium Akkermansia muciniphila as a treatment for preventing obesity and metabolic disorders associated with it.

References

1. Everard, A., Belzer, C., Geurts, L., Ouwerkerk, J. P., Druart, C., Bindels, L. B., ... & Cani, P. D. (2013). Cross-talk between Akkermansia muciniphila and intestinal epithelium controls diet-induced obesity. Proceedings of the National Academy of Sciences.

2. Backhed, F., Ding, H., Wang, T., Hooper, L. V., Koh, G. Y., Nagy, A., ... & Gordon, J. I. (2004). The gut microbiota as an environmental factor that regulates fat storage. Proceedings of the National Academy of Sciences., 101(44), 15718.

New ribbon like nanostructures assembled by DNA binding method

0
0
U.S. Department of Energy's Brookhaven National Laboratory scientists have made a novel discovery; DNA strands used as linkers can coax nano-sized rods to line up in way previously unseen in any other spontaneous arrangement of rod-shaped objects. The arrangement, with the rods forming "rungs" on ladder-like ribbons linked by multiple DNA strands, results from the sum of interactions of the flexible DNA tethers and may be unique to the nanoscale.

This new discovery could result in the fabrication of new nanostructured materials with desired properties.

Brookhaven physicist Oleg Gang said: "This is a completely new mechanism of self-assembly that does not have direct analogs in the realm of molecular or microscale systems,", Gang is the lead author on the paper, and conducted the bulk of the research at the Lab's Center for Functional Nanomaterials.

Many different classes of rod-like objects, from molecules to viruses, often exhibit classical liquid-crystal-like behavior in similar systems, where the rods align with a dependence on direction, sometimes with the aligned crystals forming two-dimensional planes over a given area. Rod shaped objects with strong directionality and attractive forces between their ends, resulting, for example, from polarized charge distribution, may also sometimes line up end-to-end forming linear one-dimensional chains.
The interesting thing is that neither of these typical arrangements is found in the DNA-tethered nanorods.
"Our discovery shows that a qualitatively new regime emerges for nanoscale objects decorated with flexible molecular tethers of comparable sizes-a one-dimensional ladder-like linear arrangement that appears in the absence of end-to-end affinity among the rods," Gang said.

Alexei Tkachenko, the CFN scientist, who worked up a theory to explain such exceptional behavior, explains:
"Remarkably, the system has all three dimensions to live in, yet it chooses to form the linear, almost one-dimensional ribbons. It can be compared to how extra dimensions that are hypothesized by high-energy physicists become 'hidden,' so that we find ourselves in a 3-D world. Once a nanorod connects to another one side-by-side, it loses the cylindrical symmetry it had when it had free tethers all around. Then, the next nanorod will preferentially bind to another side of the first, where there are still DNA linkers available."

The central approach of Gang's research at the CFN has been the idea of using synthetic DNA as a form of molecular glue to guide nanoparticle assembly.

In his previous work he has shown that strands of DNA can pull nanoparticles together when strands bearing complementary sequences of nucleotide bases are used as linkers, or inhibit binding when unmatched strands are used. Carefully controlling those adhering or repulsing forces can lead to fine-tuned nanoscale engineering.

In this study, the scientists used nanorods made of gold and single strands of DNA to explore the arrangements made with complementary tethers attached to adjacent rods. They also experimented with the effects of using linker strands of different lengths to serve as the tethering glue.

They studied the resulting arrangements using ultraviolet-visible spectroscopy at the CFN, and also with small-angle x-ray scattering at Brookhaven's National Synchrotron Light Source.
To better understand how the process progresses over time they used a technique to freeze the assembly in several points and then use scanning electron microscopy to get the images.

This specific assembly process, called hierarchical, is reminiscent of self-assembly in many biological systems.

Stopping the assembly process at the ladder-like ribbon stage could potentially be applied for the fabrication of linear structures with engineered properties. For example by controlling plasmonic or fluorescent properties-the materials' responses to light-we might be able to make nanoscale light concentrators or light guides, and be able to switch them on demand." Gang said.

Paper published online in ACS Nano, a journal of the American Chemical Society

Biotech. Research Thrusts of IITs

0
0
In the last few years, the academic domain of Biotechnology sector has seen some real boom in India. A rat race can be seen among various private institutes in offering a variety of Biotechnology courses/diplomas/degrees. The surge is really high in the "quantity" of institutes, but the "quality" is offered by very Few! And, among all the big names in educational sector, IITs (Indian Institute of Technology group) stand tall as the dream destination for every student (Biotech Students are No Exception!). The quality they offer, and added to that the brand name of IITs take a student on a path to a bright and proud scientific/business career.

Here in this article, my focus would be on highlighting,"What IITs have in offering for Biotechnology students/aspirants?". The research thrusts of various IITs (Top 7) will be en-lighted herein:

Indian Institute of Technology, Delhi (IIT Delhi):
Starting with IIT Delhi (my Alma mater ), it has a dedicated "Department of Biochemical Engineering & Biotechnology (DBEB)" and "Kusuma School of Biological Sciences".
IIT Delhi is the best place for an aspiring Bioprocess/Biochemical Engineer, that's what DBEB is well renowned for! Ever since the day of it's initiation as long back as 1968 (one can imagine the expertise and reputation of the department), DBEB's research has been focused on industry relevant Bioprocesses and Products. Their experience in Enzyme and Microbial Systems is beyond comparison. They have a unique experience of cultivation of plant cells in big bioreactors (3-15L), commercialization of biofertilizers, bio-ethanol production, working on Nano-particle mediated drug delivery, application of molecular motors. They are one of the oldest experts in Bioprocess Modelling & Simuation too. The state-of-art facilities at DBEB include high through-put molecular biology equipments, a wide range of bioreactors (have a dedicated pilot plant with 300-1000L reactors), whole range of upstream and downstream processing instruments etc. Here's a link to the DBEB Departmental Website of IIT Delhi: DBEB IIT DELHI

The Kusuma School of Biological Sciences at IITD, is a rather new establishment (2008) and has core molecular level, structural level and system level research thrusts. It's famous for research on healthcare/disease prospects through emphasis on signal transduction, chemical biology, virology, immunology and computational biology etc. Here's a link to Kusuma School of Biological Sciences, IITD: KSB

Indian Institute of Technology, Mumbai (IIT Bombay)
Indian Institute of Technology Bombay is the place if being a Biomedical Engineer is what you aspire the most. Hard core research on cancer biology, nano-medicine, nano-robots, prosthetics, biomedical instruments is done at Department of Bioscience and Bioengineering (DBSBE) IITB. Though they have expertise on bioprocessing too viz. fungal cultivation for enzymes, use of plug-flow reactors etc, their expertise in Biomedical Engineering is incomparable. Recently in Jan 2012, IITB inaugurated Wadhwani Research Centre in Biosciences and Bioengineering (WRCBB), with an aim to upthrust the research prospectives of DBSBE in cancer research. WRCBB will be focussing on Cell Motility and Cancer Invasion apart from the core thrusts of DBSBE.DBSBE IITB

Indian Institute of Technology Madras (IIT Madras)
Founded in 2004, the Department of Biotechnology of IIT Madras has wide range of research thrusts viz. Biomaterials and Tissue Engineering, Computational Neuroscience, Biochemical and Bioprocess Engineering, Stem Cells and Molecular Biology, Genetics, Drug Designing etc. But, their experience in Bioprocess Engineering is quite famous among the industries, and it won't be wrong in saying that after IITD, IIT Madras shines high in Bioprocess/Biochemical Engineering.
Biotech IITM

Indian Institute of Technology Kanpur (IIT Kanpur)
IIT Bomabay and IIT Kanpur share quite a comparative profile in research thrusts. Both the IITs are well known for producing world class Biomedical Engineers. The thrust on Molecular Scale research aimed at cancer therapeutics, Neurobiology of disorders and stress biology, Modelling and dynamic studies of chromosomes etc is very prevalent at IIT Kanpur. Apart from this, their focus is on Bioprocess and Bioremediation too, but it's not as developed and advanced as their expertise in Biomedical Sciences. BSBE IITK

Indian Institute of Technology Kharagpur (IIT Kharagpur)
IIT Kharagpur, like IIT Delhi, has rich interest and focus on Biochemical and Bioprocess Engineering. Their work on Enzyme and Biofuels Technology, Bioenergy, Probiotics and Nutraceuticals, Environmental Biotechnology, Algal Biofuels and Bio-CCS, Biorefinery, Bioprocess Development Modeling & Optimization, Marine Biotechnology, Biohydrogen production processes etc is very well renowned and published in hundreds of research journals (IIT Kgp is rather famous for publications). Apart from the Biochemical Engg., they have good expertise and facilities in Cell based tissue engineering and regenerative medicine, Structural Biology and Protein Chemistry and Bioinformatics and Computational Biology.
Biotech. IIT Kgp

Indian Institute of Technology Guwahati (IIT Guwahati)
IIT Guwahati has a wide range of Biotechnical research thrusts, with key focus on molecular scale of developments. Their researches on Hormonal regulation of gene expression, Cell based tissue engineering, Biomaterials, Stem cells, Drug delivery systems, Calcium signaling, DNA repair, Gene Therapy, Expression Cloning (Mammalian Systems, Bionanotechnology, Protein Biochemistry and Biochemical Parasitology etc is well accredited. Their faculty profile in Biochemical Engineering & Modelling is very nice, but their expertise is brilliant in molecular research.
Biotech. IITG

Indian Institute of Technology Roorkee (IIT Roorkee)
IIT Roorkee's Department of Biotechnology is grouped into various research groups like Molecular Biophysics Group, Molecular Genetics Group , Reproductive Biology Group, Plant Biotechnology Group , Microbial Biotechnology Group, Molecular Biology & Proteomics Group etc. The core-thrust has again been molecular scale research here too. For some unknown reasons, most students are unaware of IIT Roorkee's Biotechnology expertise which dates back to 1980. Their biotechnology lab facilities are state of art, and research prospectives are bright there. Rather, IITR offers a wide range of expertise which makes them quite a flexible research hub.
Biotech IITR

So, this was a very brief overview of the research thrusts of top 7 IITs of India in the field of biotechnology. A specific detail on faculty, students & labs of these IITs may be had from the "Red Links" mentioned at the end of every IIT's detail.
Thanks

Huge Step in Progeria Understanding and Promising Treatments

0
0
In modern classification, progeria has few different varieties, but most common is Hutchinson Gilford Progeria. Progeria or Hutchinson Gilford Progeria Syndrome is very rare genetic disease. This disease is known as extreme aging disease. Characteristic of these patients is that they are children and their mortality is very high between age of 7 and 20. This severe disease occurs in one patient in 8 million live births. Genetic basis of this disease is mutation, that means it is cannot be inherited. Symptoms of this disease are manifested in first few months. Main symptoms of Hutchinson Gilford Progeria are wrinkled skin, atherosclerosis, loss of eyesight and kidney failure. Their body is very fragile like those of elderly people.

According to several researches, progeria is caused by a gene mutation. People without this mutation have normal LMNA gene which creates Lamin A protein. This protein is responsible for keeping the cell nucleus together. People with progeria, have mutation on LMNA gene, and this mutated gene produces defective Lamin A proteins. These defective Lamin A proteins make their cells unstable.

This disease is very rare, maybe few hundred people have these severe disease, but it intrigued scientists because finding a cure for this disease could give answers for aging process.

Current progeria treatment

There is no cure for progeria, but cardiovascular monitoring could help in treatment of progeria disease. Low dose aspirin, symptomatic drugs such as use of growth hormone, statins to lower cholesterol level and other could be used in treatment of progeria.

Experimental drug could prolong life

Researchers have discovered the first drug to treat progeria. Farnesyl transferase inhibitors is a new medicine which could help people with this severe disease. This drug, called lonafarnib, is not a drug that can cure this disease. This medication has shown that it can reverse changes in blood vessels which can cause strokes and heart attacks. Another benefit for children with this disease could be possibility to put on weight and improve structure of their weak bones.

However, because of the length of the study, scientists are not sure can the treatment prevent an early death or not. But, observations of the parents are also important. Mothers of children with progeria noticed that when their children took lonafarnib, they had more energy, concentration, and also they slept and ate better. These observations can be very helpful in further researches, because they implicate that lonafarnib had positive effects on their children.

Of course, these findings are just a beginning of future experiments. In presence, few studies are under way to reveal is there a better solution for progeria treatment with maybe, combination of two or more medications. All these researches could help us understand how aging takes its place in our individual cells. The most fascinating thing that scientists didn’t know what causes progeria for a decade ago.
The newest discoveries in progeria treatment
Recently, researchers have discovered that drug that inhibit an enzyme in living organism can help in progeria treatment. In Sahlgrenska Academy in Sweden, researchers have discovered significant improvement in mice with progeria when production of certain enzyme is inhibited.

Researches believe that this finding could be crucial for further understanding and treating of progeria. They have proven that symptoms of progeria are definitely reduced or even blocked when certain enzyme is inhibited. Also, they have compared their findings on mice with cultured cells of children, and they came to conclusion that the growth of human cells is almost identical with mice cells. This target enzyme is called ICMT. This enzyme attaches a very small chemical group to one end of prelamin A. When scientists discovered this, they focused on it, and began research to prevent small chemical group attachment to prelamin A. They succeeded in their intention, and they have managed to block this enzyme. When ICMT is blocked, chances for progeria development are significantly reduced.

Group of scientists from Singapore has developed new medicine for progeria treatment. However, this candidate drug is based on ICMT inhibition, and it is still under research, but as soon as this candidate drug is ready, it will be examined on mice. Of course, time will show wheather this drug is appropriate for treatment of progeria or not. This findings are maybe even bigger than we can imagine, because people affected with progeria are not so big population, just few hundreds of them, and it is really interesting how big interest is for this disease.

Summary and conclusion

Progeria is disease that was almost unknown for a decade ago. However, big efforts of scientists have shown results. Now, we understand better what progeria is, and how it could be cured. Unfortunately, there is no cure for progeria. There are some experimental drugs under development. But in every way, these drugs will help people with progeria, and some cures can maybe prevent its development. Many drugs have focus on progeria symptoms, and they can help in problem treatment like osteoporosis, muscle weakness, myocardial infarction, stroke and other problems occurred in progeria disease. Other drugs have focus on inhibition of ICMT enzyme.

Another benefit from these researches is possibility of getting answers and revealing process of aging. This disease, called progeria, has maybe important answers which can help scientists to understand aging process. One of the most interesting things in progeria is thing that these patients have many symptoms like old persons, but some properties are exceptional. They have eyesight loss, osteoporosis, muscle weakness, kidney failure, wrinkled skin, atherosclerosis, and other symptoms, but they never develop cancer or dementia. When scientists figure this fact out, they could provide us some wanted, bud unfortunately unknown data of our aging process. Maybe these data could prolong our lives, or even prevent cancer and dementia development in near future.

Tooth Regeneration: Grow Your Teeth Like an Alligator!

0
0
Although the mere notion of the alligator teeth could give us creeps, scientists hope that within these scary jaws lies the clue for successful tooth regeneration in humans. A latest research appeared in the journal Proceedings of the National Academy of Sciences, in May 2013, provides an insight into the regulation of multiple tooth regeneration of the American alligator. The researchers predict that understanding the mechanisms related to the development and renewal of tooth in this crocodile model will be useful in finding a way to stimulate the teeth regrowth in adult humans.

Alligator teeth are not that different from ours!

Crocodiles exhibit the same complex dental architecture and morphological characteristics as mammals such as thecodont teeth (teeth that are embedded in sockets). They also have a secondary palate like that of the mammals. In addition, unlike humans, they have the capability of renewing their teeth many times within their lifetime. Thus the alligators can be considered a classic model to be used in tooth regeneration studies.

One crocodile tooth renews about 50 times

Crocodiles are polyphyodont i.e., their teeth are continuously shed and replaced during the existence of the animal. It is estimated that one crocodile may replace each of its 80 tooth about 50 times throughout its lifespan. Humans however, are diphyodont, meaning that they can grow only two successive sets of teeth within their lifetime: the deciduous (milk) teeth, which are followed by the permanent (adult) teeth. After that they lose their ability for tooth renewal.

The present study observed that each tooth of an alligator behaves like a complex ‘family unit’. Each of these units comprises of a functional tooth which is the most mature tooth, a successional tooth that will later be developed in to a functional tooth and the dental lamina. These components were found to be at different stages of development. Furthermore, the researchers were able to identify a type of cells in the dental lamina of the alligators which they suspect to be dormant teeth stem cells that can be activated when a functional tooth is shed or extracted.

The research also provides information about the signalling molecules that plays a critical role in tooth development and renewal of the alligators.

Humans may have the potential for tooth regeneration

Dental lamina, the source of odontogenic stem cells for cyclic tooth regeneration, usually begins to degrade in humans after the generation of secondary tooth. Thus the humans lose the ability of regenerating their adult teeth. However, a remnant of it still exists and may initiate odontogenic tumors later in life. Previous literature reveals the presence of teeth stem cells in adult humans. Although these cells retain the ability of differentiation, they cannot generate a whole new tooth.

the following video can provide a basic idea of human tooth development.




No more dentures!

Tooth loss is a common problem that may occur due to various reasons including fractures, physical injuries, tooth decay and infections of the gum. Though this condition is rarely critical, it often results in aesthetic and psychological concerns thus necessitating in replacement of tooth.

Current options available for tooth replacement include techniques such as dental implants made out of biocompatible materials like titanium that can be inserted in the teeth bone. However the success of these implants is not completely satisfactory in terms of their performance and long-term stability. Therefore, many recent researchers focus on the potential of odontogenic stem cells to grow living tooth with proper functional characteristics. Several studies report regeneration of teeth using stem cells in vitro, although their use in dental practice is still challenging owing to factors such as high risk of rejection.

The current research however, promises of a future potential of regeneration of teeth in vivo. These findings suggest the possibility of using this knowledge for stimulating the dormant stem cells present in the remnant human dental lamina to initiate tooth regeneration process. In addition, the researchers hope that this will help in treating oral diseased that involve supernumery teeth formation.

Reference

Wu, P., Wu, X., Jiang, T. X., Elsey, R. M., Temple, B. L., Divers, S. J., ... & Chuong, C. M. (2013). Specialized stem cell niche enables repetitive renewal of alligator teeth. Proceedings of the National Academy of Sciences.

http://www.pnas.org/content/early/2013/0...0.abstract

The Good Fat and The Bad Fat

0
0
Today, Obesity & Fat are more or less considered synonyms of each other! The changing life styles has today resulted in around 37.5% of US population as "Obese" , with high risk/vulnerability to obesity related disorders like cardiac disorders, type 2 diabetes, few types of cancers, strokes etc (The scenario is similar in other parts of the world as well!). According to Center for Disease Control & Prevention, US (CDC US), an obese person spends on an average $1,429 more than a normal person on his/her medical bills alone! As a result, the 'obesophobic' people tend to become 'fat-phobic'-no matter what kind of fat it is! Unaware of the fact that "Not All Fats Are Bad! Some Are Good Too! And Needed By The Body!"

So, in this article, I would like to shed some light on the facts of existence & significance of The Good Fat & The Bad Fat.
[Image: good_fats_vs_bad_fats.jpg]

The Bad Fat
Let's start with the fact file of the 'Bad-Fat' of which most of the people (obese/non-obese) should actually fear-off! Most of the health conscious people fear the high intake of calories associated with the fats, due to which they tend to curb their consumption of fats. Such a strategy of avoiding fat may work well in case of 'Bad-Fats', because it's not the calories associated with the fat, but actually the nature of fat itself which has determining effects on the health/obesity. Saturated fats & Trans Fats together make "The Bad-Fat Family". Now, the reason behind their bad nature is quite chemical! If one looks into the chemical structure of Saturated fats (as the name suggests), they are full of hydrogen atoms with strong -C-H- bonds all around, making their hydrolysis extremely difficult. leading to their accumulation in the body. Saturated fats are characterized by all round presence of single bonded C and H atoms, with no double/triple bond. Image below indicates the same well:
[Image: saturated.png]
And, for a layman's recognition, beware of Beef, lamb, pork, poultry with the skin, lard, cream, butter, cheese, other whole or reduced-fat dairy products! They are all rich in Saturated Fats! Among oils, Coconut and Palm Oil are rich in saturated fats.

Trans fats on the other hand are mostly originated by man through industrial process of partial hydrogenation of vegetable oils. So, chemically, they do have double bonds, but the unique geometric configuration of the double bond(s), creating a trans isomer adds the 'bad' attribute to the other wise unsaturated fatty acid. Following is a depiction of trans and cis form of unsaturated fatty acids:
[Image: Elaidic_acid_2_D_skeletal.png] [Image: 500px_Oleic_acid_skeletal_svg.png]
trans fatty acid and cis fatty acid

The unique geometrical configuration of trans-fats allows them to pack tightly among each other, leading to very high boiling points and resistance to hydrolysis. This again leads to their accumulation in the body. Infact, they are a source of accumulation of high contents of LDL cholesterol, which is fatal for cardiac health! Common sources of trans fat include pastries, biscuits, muffins, cakes, pie crusts, doughnuts, French fries, fried chicken, breaded, chicken nuggets, popcorn and stick margarine.

The Good Fat
As I said earlier, not all fat are bad! Yes, there are some kinds of fat whose intake can rather do the damage repair to the body. They belong to two categories (chemically): polyunsaturated fatty acids (PUFA) and Monounsaturated fatty acids (MUFA). PUFA and MUFA, as they are commonly called, are healthy fats, whose intake reduces the bad cholesterol (LDL cholesterol) from the body and they don't accumulate in the body as fat droplets, lowering the risk of heart diseases.

Starting with MUFA, as the name suggests, they contain "single double bond" and their healthy variants have cis configuration (MUFA in trans configuration become trans fats!). The double bond and cis configuration makes the structure unstable, with low melting/boiling point, making them liquid at room temperature and solid when chilled. Examples include: Vegetable oils like olive, canola, peanut and sesame; Avocados; Many nuts and seeds like almonds and peanuts/peanut butter.

PUFA contain multiple double bonds in their structure, all of which are easily hydrolysable, making the PUFAs non-accumulating in the body (Again, only cis-from is healthy). Two special types, named omega-3 and omega-6 fatty acids are established healthy variants of PUFA, which are rather "essential fatty acids" as they cannot be synthesized in the body itself, and their intake is essential for proper biological functioning. Whereas omega-3 is essential for normal growth in youngs and synthesis of anti-inflammatory Eicosanoids in the body, omega-6 are essential for synthesis of prostaglandins (for healing of tissues and sensation of pain). PUFA consumption keeps the heart diseases at the bay and lower the LDL cholesterol levels.
[Image: 500px_ALAnumbering_svg.png]
alpha-linolenic acid (Omega-3)


Common sources include: soybean, corn and safflower oils, – walnuts and sunflower seeds; and fishes like salmon, tuna, mackerel, herring and trout .

Does That Mean: Consume A Lot Of Good Fat??
No! Not at all! It will lead to weight gain. Every fat has relatively high calorie content as compared to carbohydrates/proteins. So, if you will consume excess of good fat too, it will lead to excess calorie intake, which might translate into weight gain. A better strategy is to replace all your fat consumption with good fats and follow a balanced diet regime. Use of good fat will reduce the risk of heart diseases, which is amplified when you regularly use the bad fat!

So, I hope this article gave you a brief insight into the significance of "not-completely removing" fats from your diet. There's a distinct importance of having fats in the diet, which is essential for structural development of your body (imagine, each cell is having a lipid bilayer!). So, wisdom is in choosing the right fat, and not fearing all fats out of fear of getting fat!

Thanks

I am new here guys..

0
0
hey guys.. I am just new in this forum looking to get some really helpful information about the biotechnology..I hope it would be the best experience for me..
thanks in advance for your further cooperate guys..

Help Shortlisting - Keck vs. South Carolina vs. North Eastern university

0
0
Hi have received admits from Keck's graduate institute, University of South Carolina and Northeastern university for masters in biotechnology. Which one should i choose? Please help!Huh

Crabtree Effect : A Significant Fermentation Control

0
0
April 22, 1929 Biochemical Journal (Bioechem. J) published a research by Herbert Grace Crabtree (From the Laboratories of the Imperial Cancer Research Fund, Queen Square, London) titled "Observations On The Carbohydrate Metabolism Of Tumours". His research led to a highly significant finding which had implications on almost every future research on fermentations. The finding was "Effect of glycolysis on respiration", which suggested that the glycolytic activity exerted a checking effect on the respiration powers of the cells (of specific kind(s)). This inhibition of respiration under high rate of glycolysis emerged as Crabtree Effect. The effect was later elaborated by R.H. De Deken (C.E.R.I.A., Brussels, Belgium, 1965) in the most common eukaryotic model organism for fermentation: Saccharomyces cerevisiae, describing it as 'a repression of an energy source (respiration) by another energy source (fermentation/glycolysis)'. Owing to it's contrary nature to Pasteur effect (which is the inhibition of fermentation by respiration), it was quoted as 'contre-effet Pasteur' ". This article will thus focus on unfolding the concept of Crabtree Effect, and it's significance in industrial/research based fermentation processes.

Crabtree Effect: The Concept

Crabtree effect refers to inhibition of respiration when glucose concentration is increased (or when glycolysis is increased). It is observed in glycolytically active cells (like those involved in fermentations e.g yeast; and tumor cells), and not in every cell (which is contrary to Pasteur effect, observed in all kinds of cells). The mechanism behind the Crabtree Effect can be well understood in terms of [ATP]/[ADP][Pi ] ratio (Sussman et al., 1979). It's the cytosolic [ATP]/[ADP][Pi ] ratio which regulates the rate of respiration and glycolysis in the cells. But, the regulatory mechanism of both the processes is entirely different, which ultimately leads to Crabtree Effect in such cells.
The regulation of respiration is controlled by free energy of hydrolysis of ATP (following equation gives an overview of Free Energy of ATP Hydrolysis):
[Image: free_energy.png]
Click here for Full Concept on Free Energy of ATP Hydrolysis
Decrease in [ATP]/[ADP][Pi ] thus leads to an increase in the respiration rate, and increase in [ATP]/[ADP][Pi ] leads to a decrease in respiration. On the other hand, regulation of Glycolysis is positively controlled by ADP (AMP) and Pi and negatively by ATP (thus again, decrease in [ATP]/[ADP][Pi] leads to increase in glycolytic rate, while increase leads to decrease in the glycolytic rate). So, as evident, both respiration and glycolysis are regulated by the same set of factors, but by entirely different mechanisms. Now, this distinguished control of respiration and glycolysis is what leads to Crabtree effect. To elaborate, since Crabtree Effect takes place only in those cells which are glycolytically active, an increase in glucose conc. will push it towards glycolytic pathway, leading to an increased ATP production (consuming ADP and Pi, from media). This would tremendously increase the [ATP]/[ADP][Pi ] ratio, seriously lowering the free energy of ATP hydrolysis, and hence decreasing the rate of respiration to huge extent! (But, the glycolysis induced increase in [ATP]/[ADP][Pi ] won't necessarily reduce the glycolytic rate itself, as it's dependent on ADP (AMP) and Pi too, which is often present in good amounts in medium, to activate the enzymes responsible for glycolysis; more over the inherent glycolytically active nature of the cells keeps the inhibition of glycolysis itself at the bay!). So, this is how in most simple terms, Crabtree Effect takes place.

Significance (where Crabtree is Observed in Real World):

Alcohol Production:
The alcohol production industry is highly dependent upon the Crabtree active Saccharomyces cerevisiae. Yeast produces alcohol only under anaerobic conditions (which must be maintained for higher alcohol output!). Under aerobic conditions, oxidative phosphorylation takes place, which stops the use of glycolytic pathway. But, if excess of glucose (substrate) is supplied to the culture, then Crabtree effect takes place, and respiration is inhibited even if aerobic condition prevails! This leads to excess production of alcohol rather than biomass production. So, Crabtree comes to a favorable use in alcohol industry.

Tumor Cell Growth:
Tumor cells are characterized by hypoxic environments, where oxygen and nutrients are greatly limited. Their ability to produce lactate (and efficient glucose use) enables them to suppress the respiratory and oxidative phosphorylation need, and still survive by active glycolysis. Again, this is an instance of Crabtree Effect!

Concluding:
The research on Crabtree Effect is still active, despite it's first citation in 1929. Major part of the research is rather focussed on zeroing-in on the exact mechanism of the effect, which has received several reviews through out the time of it's proposition. The mechanism discussed in this article is one of the widely accepted ones, and nicely explains the Crabtree activity of certain cells. It's involvement in alcohol production (a ubiquitous industry), itself makes it a topic worth research and development. And, I hope, the next time you might see some cells respiring anaerobically, despite the presence of aerobic conditions, you should reason it with "Crabtree" as one of the probable factors!

Thanks

Now we can produce starch from cellulose!

0
0
No Food? Eat Wood!

Plants give us food. But the question is can plants produce enough food to feed the growing global population that is estimated to reach 9 billion by 2050? Many statistics estimate they can’t. But a solution may not be far, predict the scientists. A new method of enzymatically converting cellulose, the structural polysaccharide in plants, into edible starch has been discovered by a group of researchers at the Virginia Polytechnic Institute.

Cellulose is the most abundantly occurring organic material in the biosphere. many kilogrammes of cellulose is said to be synthesized and degraded on earth each year. Finding a way to convert this cellulosic waste into utilisable forms has been the interest of many researchers for decades. However, due to the presence of strong binding forces between the cellulose molecules, hydrolysis of cellulose is relatively difficult compared to the breakdown of other polysaccharides.

This remarkable discovery, a bioprocess called ‘Simultaneous Enzymatic Biotransformation and microbial Fermentation’ (SEBF), provides a means of producing not only amylose, the unbranched form of starch, but also bioethanol and single cell proteins in a one-pot bioconversion process. Researchers declare that up to 30% of cellulose can be hydrolysed into starch while the remainder is converted into glucose which is then fermented into ethanol by yeast in the same bioreactor.
Following is a simplified summery of the process and the economic prospects of its products as depicted in the published report of the study in the journal PNAS on 15th April 2013.

Although the three processes; hydrolysis of cellulose, synthesis of amylose and production of ethanol occur simultaneously in the bioreactor, this process can be broken down into several steps for the sake of understanding.

Step 1 : Pre-treatment of cellulose biomass

The enzyme mixtures employed in this study were optimized for efficient hydrolysis of amorphous cellulose rather than of crystalline cellulose and hemicellulose- and lignin-containing biomass. Since natural plant biomass contains lignin and hemicellulose together with crystalline cellulose, interlinked in a hetero-matrix which is highly resistant and thus not efficiently degraded by enzymes alone, some kind of pre-treatment is necessary to make the biomass more accessible to enzymes.

In this experiment, insoluble Regenerated Amorphous Cellulose (RAC) was used as the source of cellulose. RAC was prepared by pre-treating Avicell® (a commercially microcrystalline cellulose powder) with concentrated phosphoric acid.

Step 2 : Breakdown of pre-treated cellulose biomass into cellobiose

In this step, a combination of two enzymes, Bacillus subtilis endoglucanase (EG) and Trichoderma spp. Cellobiohydrolase hydrolyses (CBH) converts cellulose into glucose and cellobiose which is a disaccharide consists of two glucose molecules.

Among five cellulose enzymes tested in the study, the combination of Bacillus subtilis endoglucanase and Trichoderma spp. Cellobiohydrolase proved to produce higher cellulose degradation resulting in high cellobiose yields.

Step 3 : Synthesis amylose from cellobiose

Produced cellobiose is then polymerised into amylose, a linear polysaccharide made out of glucose monomers linked together with alpha-1,4-glycosidic bonds and alpha-1,6-glycosidic bonds. Two enzymes, Clostridium thermocellum cellobiose phosphorylase (CBP) and potato alpha-glucan phosphorylase (PGP) are used catalyse this reaction.

Here, cellobiose is first converted into Glucose-1-phosphate and glucose by CBP and then the resulting Glucose-1-phosphate is linked together by PGP, forming amylose chains.

Three αGPs, one from potato and the rest from two thermophilic bacterial species were tested. Among them, only the potato αPG (PGP) was able to facilitate the synthesis of amylose.

Step 4 : Fermentation of glucose into ethanol

Glucose produced in the steps two and four are then fermented into ethanol by the yeast strain Saccharomyces cerevisiae. The yeast biomass can be used as Single Cell Proteins.

Step 5 : Product recovery

At the end, ethanol can be separated by distillation. The precipitated synthetic amylose can be extracted with NaOH following precipitation by neutralization. The yeast cells and the biomass residues will remain in solid pellets.

The enzymes were recombinantly produced in Escherichia coli. The enzymes were co-immobilised on Avicel-containing nanomagnetic particles, enabling their recovery with the use of a magnetic field.

See the attachment for a simplified flow chart of the process.

.pdf  Simultaneous Enzymatic Biotransformation and microbial Fermentation.pdf (Size: 43 KB / Downloads: 2)


Economic viability of the process

This method yields three products; amylose, Bioethanol, and yeast as single-cell proteins which are of immense commercial significance. Amylose can be used for various purposes including drug capsule materials for the pharmaceutical industry, biodegradable plastics, food additive, food-grade amylose, high-density hydrogen carrier etc. Amylose also can be converted into branched amylopectine by alpha-glucan–branching glycosyltransferase enzymes. Ethanol can be used for the production of biofuels and the SCPs together with the residual amylose can be used as animal feed.

Furthermore, the efficiency is enhanced because no energy or costly chemicals are required, the immobilised enzymes can be easily recovered and no glucose is wasted.

Further scaling-up

The researchers hope to further improve the process to ensure a sustainable industrial scale application of the process. Increasing the stability of CBP and PGP and decreasing their production costs, optimizing the enzyme mixture composition and ratio, improving process design and biomass pre-treatment conditions are some of the key areas they hope to look into.

Source:

You, C., Chen, H., Myung, S., Sathitsuksanoh, N., Ma, H., Zhang, X. Z., ... & Zhang, Y. H. P. (2013). Enzymatic transformation of nonfood biomass to starch. Proceedings of the National Academy of Sciences, 110(18), 7182-7187.

Tips for Admission in National University of Singapore

0
0
National University of Singapore (NUS), a government controlled central University of Singapore, is among top universities in the world. According to the latest Quacquarelli Symonds (QS) World University Rankings (by subjects), NUS is ranked 8th in the world, giving a glimpse of it's standards!

Now, without wasting much time on the general facts about the NUS, let's shift to the focal point-"Scope of Biotechnology in NUS". Following are the Schools/Faculties encompassing Biotechnical domain at NUS:

Department of Bioengineering
The key focuses of Bioengineering Department are Biomaterials, Biomechanics, Bionanotechnology, Biosignal Processing, Biosensors, Biomicrofluidics, Computational Biology with application in areas of Tissue Engineering, Therapeutic Delivery Systems, Biomedical Imaging and Instrumentation, and Medical Devices.

Department of Chemical & Biomolecular Engineering
As the name suggests, this department represents a nice amalgum of Chemical Engineering & Molecular Scale Biological Research. In their own words,"the Department provides the critical link between engineering and the sciences, particularly the chemical and life sciences, by bridging the gap between molecular-level, laboratory-scale studies of chemical and biological transformations and the large-scale industrial production operations". The application areas include biomedicine, protein engineering, drug-delivery systems, chemotherapeutic engineering, and smart materials (e.g., for biosensors, molecular and polymer electronics, novel smart membranes for separation processes and novel optoelectronic and photonic materials) etc.

Department of Life Sciences
This department is one of the oldest front-runner in biological research at NUS (since 1949-50). It covers broad aspects in biological field ranging from Plant Growth & Development, Biotechnology, Biodiversity & Ecology, and Structural Biology, Functional Genomics & Proteomics and Fish Biology & Aquaculture.

Where These Departments Stand in World:
These three departments represent the crust & core of Biotechnical scope at NUS. And to give you an estimate of the repute of these departments, I have enlisted their world ranks (QS Ranking):
  • Department of Bioengineering: World Rank 6
  • Department of Chemical & Biomolecular Engineering: World Rank 6
  • Department of Life Sciences: World Rank 17

The US & Europe Paradox:
What I want to highlight here is the fact that most of the students of Biotechnical background (especially in India) follow the long-standing trend of pursuing higher education (PhD/PostDoc) at either US/Europe. For, them it's US/Europe only where biotechnology booms big and bright! And, considering the fact that the percentage of acceptance at US universities is quite low, almost all the budding bio-technologists end up either in Germany (considered the hub of biological research). This according to me is a paradox out of lack of awareness about the international repute of some of the Asian Universities, to which even US students dream of seeking admission! And, considering the rankings of these departments at NUS, the paradox must be broken!

Admission Facts About NUS:
Here I won't share details about the application process for the admission (you may easily find the same at NUS's website. I have shared the link though, below.)
Click here for NUS Admission Process

My focus would rather be on those facts which should make you feel that getting admission in NUS is rather way too easy & beneficial than US/Europe Universities:

1. Preference to Developing Countries:
They prefer students from different cultural backgrounds, especially students from developing countries. They have a special inclination towards Indian talents.

2. Easy Selection Criteria:
Their selection criteria for interview call are very simple:

**They accept GATE Score and GATE Cut-off is 90 percentile (which means even if you manage to qualify GATE just by 1 or 2 marks above the cut-off marks, still you can get a call from NUS!)

**They don't need GRE if you have GATE score!

**If you don't have GATE, you may submit GRE score, whose cut-off is also very nominal: around 320 (verbal & quantitative) and 3.5 (analytical)

3. Low Application Fee:
The application fee including the postage charges is very nominal (barely above Rs 2000/-) which is too less as compared to the grueling application process for US/European countries.

4. Simple Interview Process:
The interview process of NUS is quite general and simple. It starts with a test of English through reading, comprehension and writing, the scores of which count in your final performance score. Followed by the test, a two person panel takes the interview. Through-out the years their questions have been simple as follows:

a. Tell us about yourself.

b. Tell us about your college/university.

c. Why NUS, why not IITs?

d. What if we don't have a project of your interest? Will you still join us?

Your answers to these questions decide your fate. And the confidence with which you answer really counts a lot!

5. A-STAR Application Needs No GATE/GRE/Any Test!
The most wonderful thing about Singapore govt.'s policy is A-Star Scholarship, through which students around the globe can apply at NUS/NTU Singapore, based on their brilliant profile (they may apply even without the need of GRE/GATE!). So, if your academic and co-curricular profile has been brilliant and, some how you couldn't/can't give GRE/GATE, feel free to apply at NUS through Singapore govt.'s A-Star Scholarship scheme. There is no application fee for this mode of application!! Following is the link to A-STAR details:
A-STAR GRADUATE SCHOLARSHIP


So, I hope, this piece of information might have en-lighted you all up in some way, to motivate you about the scope of Biotechnology in Asia itself! NUS is indeed a World Class University and a sure way to a successful career in Biotechnology!

Sometimes, it's the road which is less travelled by, holds the key to success!

New Clues in Understanding the Parkinson's Disease

0
0
Parkinson's disease is a degenerative disorder of CNS (central nervous system). Most people with Parkinson's disease have no specific cause of disease or they have idiopathic disease. However, little percentage of people have genetic factors as cause. Also, there are other factors related to Parkinson's disease development, but we have no proofs for them. The vast majority of patients have both environmental and genetic risk factors. These risk factors are triggers that can lead patient to this neurodegenerative disease. This disease manifests with problems of motor symptoms like uncontrollable trembling of the limbs and non- motor symptoms such as depression and sleeping disorders. Parkinson's disease is the second most common neural disease, after Alzheimer's disease.

Intraneural inclusions are described and named as Lewy bodies. In late 90's, huge discovery happened when scientists found out that Lewy bodies are created when alpha synuclein is aggregated. Since that age, scientist discovered that these alpha synuclein are progressively accumulated within the brain of the patient during the course of disease.
In this disease, alpha synuclein protein aggregates and accumulates within neurons. Some brain regions are affected with this process, and they become more and more affected as disease advances. The whole mechanism of this pathological process is not so clear, but could result from spreading of the abnormal forms of protein along nerve projections between upper and lower regions of the brain.
New experiments with alpha synuclein spreading

German scientists from Bonn have experimented on rats. They figured out the pattern of alpha synuclein protein spreading and they discovered new clues of the mechanism underlying this pathological process. However, the biggest discovery was triggering of production of human alpha synuclein in lower brain and possibility of tracing the spreading toward higher regions of the brain. This experiment and its discoveries could help us to slow down or even stop the development of Parkinson's disease in humans. However, today there is no cure for Parkinson's disease, but there are some symptomatic treatments including dopamine agonists.

Pathology results can support results

Pathology studies from human brains can contribute to research results. These studies show that these alpha synuclein accumulations are formed in lower parts of the brain. Typical place where these accumulations occur is medulla oblongata. After examination on subsequent stages of Parkinson's disease, alpha synuclein aggregations are found on higher levels of human brain such as cortical areas and midbrain.

It seems that spreading follows a typical pattern. This pattern is based on anatomical connections between various regions of the brain. Because of this assumption, it was hypothesized that abnormal forms of alpha synuclein or alpha synuclein itself can migrate from one brain region to another, in most cases from lower part to more rostral, upper part. Until now, it was not possible to target medulla oblongata to reproduce this spreading in the lab. However, there are more unrevealed things, and the biggest question is in what conditions the inter- neural passage of protein or its aggregates could be triggered. This question could be answered soon, because researchers have developed a new paradigm which could enable investigations and experiments on important and fundamental issues.

Start location of Parkinson's disease

The researchers' concept was based on creating alpha synuclein spreading in rats. Transfer of blueprint of human form of alpha synuclein into the rat brain was required in order to fulfill this concept. Specially engineered viral particles were used in transport of blueprint. After that procedure, scientists have injected it into nerve fibers in animals neck. Genetic code for the protein migrated along nerve fibers into the medulla oblongata. In rats medulla oblongata, neurons began producing huge quantities of human alpha synuclein.

Results show that scientists have solid reasons to believe that primary site of early disease development is exactly medulla oblongata. There were many reasons why scientists wanted to place alpha synuclein exactly in this part of brain. However, concept was not so simple, because medulla oblongata is not so easy to reach. They had to use vagus nerve by injecting alpha synuclein in it. This nerve was ideal because it stretches from abdomen to medulla oblongata. Because of this property, this nerve was very good solution for researchers.

Way of alpha synuclein spreading in experimental researches on rats?


Production and localization of human alpha synuclein rats brains was carefully observed by scientists during the four and a half months. As it was predicted, production and localization exogenous protein was in medulla oblongata near the connection with vagus nerve. After two months, scientist have noticed that alpha synuclein was located more distant than in the beginning. Caudo- rostral spreading involved transport of specific protein via specific nerve tract.

Possible trigger for alpha synuclein propagation

Results of the previous researches have shown that possible trigger for protein transmission is overproduction of alpha synuclein in specific brain regions. Also, overproduction of alpha synuclein is accompanied with variety of conditions such as neuronal injury, aging or genetic polymorphism. These conditions could promote development of Parkinson's disease. Because of that, many researchers results suggest a link between spreading of the protein and its pathological accumulation, disease risk factors and enhanced levels of human alpha synuclein.

The importance of insight into the early stages of Parkinson's disease

The insight into the early stages of Parkinson's disease is very important. The new model could hide the events that could possibly occur in the early stages of alpha synuclein pathology, especially when behavioral manifestations in rats and clinical manifestations in human are lacking. Because of that, it will become irreplaceable tool of investigation for mechanisms of disease pathogenesis. The biggest importance of these mechanisms is that they could be targeted for therapeutic intervention. If scientist find the way to intervene early, that would gain us a greater ability to prevent spreading of pathology or even stopping progression of disease.

Large Scale Plant Cell Cultivation: Problems & Possibilities

0
0
Plant Cell/Tissue Culture-the scientific art of growing plant cells/tissues in-vitro, has for long been considered a bright hope towards providing a sustainable source for producing plant derived therapeutically/commercially important chemicals. It not only lowers the burden on natural flora (whose reckless commercial exploitation might endanger the target plant species), but also provides a route for continuous production of plant biomass in laboratory controlled environment, independent of seasonal/climatic/geographical limitations! Following is a brief account of possibilities associated with successful cultivation of plant cells at large scale:

Possibilities in Large Scale Plant Cell Culture:

a. Fast Rate of Production
(Unlike the whole plant, cells grow very fast (doubling time of 1-2 days) under optimized culture conditions of Bioreactors)

b. Continuous Production
(Unlike whole plants, which often seed (seeds are often known to have high contents of metabolites) seasonally and according to climatic conditions, cells in bioreactor can be propagated regularly, leading to continuous production of metabolites/biomass.

c. High & Consistent Content of Target Product
(Whole plant parts are not rich in the target metabolite concentration (which is often a secondary metabolite) . Plant cells can be genetically modified and propagated in the large scale for unusually high productivities. Also, the quality of product obtained from different plants of different agro-climatic conditions is not consistent, which is not the case with the homogenous cultures of plant cells in reactors.)

d. No Pressure on Land Use
(Growing the plants on land (which is already very limited) for obtaining commercial products creates a huge pressure and imbalance. This can be completely avoided by concentrated cultivation of the plant cells in confinement of Bioreactors)

Considering the advantages of the in-vitro production of plant biomass, a lot of research has underwent in the last few decades to attempt the commercial utilization of in-vitro plant cell cultivation. Though the literature is brimmed with the laboratory scale production of numerous plant species viz Azadirachta indica (Neem; for Biopesticides), Lithospermum erythrorhizon (for Shikonin), Taxus cuspidata (for Taxol, a Cancer drug), Catharanthus roseus (for Ajmalicine) etc, very few attempts at the industrial scale have been made in the past. Some of the significant industrial attempts for large scale plant cell cultivation include Nicotiana tabacum (Tobacco, in 1500L Bubble Column Reactor, during 1970s), Lithospermum erythrorhizon (in 750L Stirred Tank Reactor, in 1985), Taxus cuspidata (in 500L Bubble Column, in year 2000) and Panax notoginseng (in 30L Stirred Tank Reactor, in year 2005). Very few of these could continue for long, and most of the attempts faced some major limitation and hurdles in sustaining the large scale cultivation of plant cells in Bioreactors. Following is a brief account of the major hurdles in scaling up the Plant cell cultivation:

Problems in Large Scale Plant Cell Cultivation:


A. Shear Stress Augmentation
The large size of the plant cells (10-100 times larger than microbial cells) and huge vacuoles possessed by them makes them extremely sensitive to shear stress and osmotic pressures. Maintaining the non-shear environment in huge vessels containing large impellers/sparging apparatus is a big challenge. Shear stresses tend to damage the cells, reducing their viability and ultimately death!

B. Aggregation
Secretion of Extra-Cellular Polysaccharides (ECP) induces aggregation and clumping of the plant cells, greatly affecting the nutrient and oxygen transfer. Clumping is an inherent characteristic of plant cells, but it’s not favorable for homogenous culture requirements. In small scale, anti-clumping agents can be economically used, but in huge bioreactors, the requirement of anti-clumping agents also shoots up! Which is unhealthy for cells as well as economy of production. Also, aggregates tend to sediment which asks for the need of increased agitation rates, which could rather lead to increased shear stress!

C. Slow Growth Rate
The slow growth rates and low biomass yields of the plant cells is another issue worth consideration during large scale cultivation of plant cells. The batch times are very large, so maintenance and monitoring needs are big. And, being one of the slowest growing living systems, the risk of contamination by fast growing bacteria/fungus also remains a factor of concern during large scale cultivation.

In order to tackle the problems associated with scale-up of plant cell culture, different groups have tried designing various kinds of bioreactors which might offer less shear stresses, ensure good mixing and keep the aggregates well dispersed in the reactor. Following is a brief account of favorable bioreactors for Large Scale Cultivation of Plant Cells:

A. Stirred Tank Reactor With Low Shearing Impellers:
Use of novel design of impellers like Paddle and Centrifuge impellers has proved successful in some cases of Large Scale Plant Cell Cultivation. They create an axial flow regime in the reactor, leading to low shear forces on the cells. Following is a visualization of the impellers:
[Image: F8287_01_wl.jpg][Image: centrifugal_pump_impeller.jpg]
Paddle Impeller and Centrifuge Impeller

Source:http://2.bp.blogspot.com/-NeOyeb5zaYU/TZ1byItYEOI/AAAAAAAADmg/x4aIdBS9v4U/s1600/centrifugal+pump+impeller.jpg


B. Air-Lift Reactor
An air lift reactor is characterized by the absence of any impeller. A special design inside the vessel (consisting of a draft tube, through which air circulates between the vessel and tube) leads to a circulation of medium through out the reactor, by the force of air. This leads to low shear stresses and high mixing.
[Image: bab0450001f03.gif]
Air Lift Reactor Design(s)

Source:http://www.babonline.org/bab/045/0001/bab0450001f03.gif

C. Bubble Column Reactor
A bubble column reactor belongs to a family of impeller less reactors. Unlike Air-lift, it lacks any draft tube and mixing is induced by the force of rising bubbles from the sparger. The rate of air sparging needs to be closely controlled, otherwise fast flowing air may lead to "bullet" action of the bubbles, creating huge shear forces on the cells.
[Image: 200px-Bubble_column.svg.png]
Bubble Column Reactor


D. Rotary Drum Reactor
It has not been used for very large scale -productions yet. But it's use in lab scale-productions has been reported in few cases. It consists of a drum (containing the biomass) partially submerged in the medium. The rotatory action of the drum ensures periods of exposure of the cells to the medium, rather than complete submergence. This arrangement provides extremely less shear force, though proper nutrient transfer is a limitation.
[Image: T0831_E12.gif]
Scheme of Rotary Drum Reactor


So, these were some of the highlights of challenges in Scale-up of plant cell cultivation. The possibilities are undoubtedly vast, and rather many companies across the globe are fast developing the technology for the exploitation of these possibilities. Recently (2010) Protalix Ltd. filed a patent for it's novel bioreactor design for cultivation of Carrot Cells in 400L bioreactor to produce the Gaucher Drug-Glucocerebrosidase! It can be used for many other plant species too! (Link to Patent Info). With such developments, it is hoped that the industrial production of plant cell biomass will soon catch the race with the well developed microbial systems.

Thanks

career in biotech

0
0
I want to know about the future of biotech in India. Please tell me whether biotech is a better choice to opt for and how is it better than simple b.sc medical and b.sc non medical on the point of job prospect?

Optopharmacology: Use of Light to Treat Pain!

0
0
Introduction:
The knowledge of light gated ion channels (the trans-membrane proteins/receptors which function in response to light) in bacterial systems has always fascinated the scientists to control the neural activity of humans (neural function is a result of a number of ion-channels) using light. The first step towards study of response of neural activity to light stimulus in animals was taken in 2003 by Georg Nagel et al. (University of California, San Francisco), through their study on ChR2 i.e Channelrhodopsin-2 (a directly light-gated cation-selective membrane channel) in C. elegans. It was expressed in the muscle cells of the body wall of the worm (an approach called Optogenetics), and it was observed that illumination caused strong contractions of the worm! Similarly, it's expression in mechanosensory neurons of the worm caused a withdrawal movement, naturally evoked by mechanical stimulation. Following video shows an experiment on Optogenetic manipulation of C.elegans behavior (Schultheis et al.,2011):


Similarly, optogenetic experiments were carried out in Drosophila, zebrafish and mice with successful observation of activation/inactivation of neural response upon light stimulus. (One must be clear with the term "Optogenetics" here. It refers to the use of techniques for expression of such genes in the nerve cells that can make them responsive to light". For e.g the expression of ChR2 in the neurons of C.elegans/Drosophilla/Zebrafish/Mice as a part of different experiments is/was an Optogenetic approach). This article is drafted to make you aware about the recent development in Optogenetics approach, which aims at use of "Light" as a drug for pain relief in humans/animals, leading to a new branch of Pharmacology-Optopharmacology!

In a recent Nature Chemical Biology publication of April 2013, Kokel, D. et al. presented his research on the discovery of a new small molecule called optovin that could make the pain sensing neurons responsive to light, without the need of any genetic tools/modification (i.e Optoactivation without optogenetics!). Discovery of Optovin was not a serendipity but a result of an organized research aimed at screening the effect of small molecules on the swimming behavior of Zebrafish. Earlier it was thought that Optovin might have been affecting the visual perception of the zebrafish to mediate the change in swimming behavior, but to the surprise of the research group, it was found that the modus operandi of the molecule is rather through a cation channel TRPA1. The TRP channels are responsible for a variety of sensory perceptions/responses viz vision, taste, temperature and touch. TRPA1, belonging to the family of TRP receptors contributes to illnesses, like neuropathic pain and chronic inflammation, whose control is mediated by optovin (a photochemical as discovered by the group), thus offers a radically new and non-genetic way of controlling the neural activity and thus the pain! Following is an interactive video of David Benett (Kings College London), explaining the role of TRPA1 receptors in Pain Sensation:



What is Optovin?
Optovin is a newly discovered "photochemical", a rhodanine-containing yellow-colored compound with peak absorbance at 415 nm, with no history of discovered biological activity till the research group of Kokel found it's role in the photosensory movements in zebrafish! It's found to be a ligand for TRPA1, but being a photochemical, it's bonding with TRPA1 can be controlled by using light stimuli! As per the reasearch, the photochemical has no adverse affects on the development of the animals (embryonic to adult stages, when tested using upto 10uM conc.). But it has marked affect on the motor neuron excitation in response to "violet" light stimuli.

Suggested Mechanism of Action Of Optovin
The photonic energy of light excites the chemical creating reactive singlet oxygen species, which induces bonding with the TRPA1 receptors (via cysteine residues) through a thioether bonding (-s-O-s-). There was no response to optovin in animals treated with DABCO (1,4-diazabicyclo[2.2.2]octane) a singlet oxygen quencher and those having point mutations leading to lack of cysteine residues at the binding site, confirming the role of singlet oxygen and thioether bonding in Optovin's action.

Scope and Way Ahead:
Optovin emerges as an entirely new class of photochemical, that directly gives access to the activity of TRPA1 receptor(s), the key protein channels responsible for pain sensation/illness/neurological disorders. None of the other photochemicals( like caged glutamate, Azobenzene, DMSO etc) were so safe and effective in-vivo, and that too with profound effects in animal models (all earlier tests were limited to petridish/culture levels). Since the control of TRPA1 through Optovin is by photoactivated thioether bonding, it can easily be reversed by changing the light stimulus. This provides a precise control over the action of optovin and thus TRPA1. The next challenge is to test the ability of optovin's action in other animals (apart from zebrafish and mice). It's activity in gating the transfected human cells has been established already by the group, paving the way for optimizing the chemical characteristics of Optovin, which could make a therapeutic drug for instant light mediated relief from pain!

Let's hope that this research moves forward very fast, and brings the days when we might use a "Torch light" to treat the "Headache"!

Fluorescent Protein-Based Biosensors

0
0
What are biosensors?

A biosensor, in simple terms, is a biological component that can sense an analyte. It contains three parts; a biological element that detects the change, a transducer element that measures the signal of the sensing element and a signal processor that displays the result.

The sensing elements include enzymes, antibodies, microorganisms, biological tissues, nucleic acid etc. and the transducer can be electrochemical, optical, acoustic, colourimetric etc.

Fluorescent Protein-Based Biosensors

In fluorescent protein-based biosensors the sensing element consists of one or more fluorescent proteins (FPs) linked to one or more polypeptide chains. The polypeptide chain acts as the molecular recognitions element (MRE) that undergoes conformational changes upon binding with the analyte, thus producing a change in fluorescence properties.
Generally, FP-based biosensors can be described under three types based on their structure.

Type I : Förster (or Fluorescent) Resonance Energy Transfer (FRET) based biosensors
Type II : Bimolecular Fluorescence Complementation (BiFC) based biosensors
Type III : Single FP based biosensors

FRET based biosensors

FRET describes the energy transfer between two chromophores. A donor chromophore, in a higher energy state, may transfer energy to an acceptor chromophore through nonradiative dipole–dipole coupling. The efficiency of the energy transfer is determined by the distance and orientation between the donor and acceptor proteins. Generally, FRET efficiency, measured by a fluorescence emission spectrum, is used to determine the proximity of the two chromophores.

In FRET based biosensors, two fluorescent proteins are genetically linked either to each end of a polypeptide chain (MRE) which is sensitive to the analyte or two separate polypeptides, the MRE and the analyte protein. Upon interaction with the analyte, conformation of the sensor protein changes, thus altering the distance between two chromophores. This causes a change in the fluorescence intensities of the donor and acceptor FPs which is measured in terms of FRET efficiency. An increased FRET efficiency indicates that the two FPs are aligned together while a decrease in FRET efficiency suggests that the donor and acceptor FPs are separated.

FRET-based biosensors are widely used to detect a range of molecular events such as protein-binding interactions, protein conformational changes, enzyme activities (e.g. proteolysis, phosphorylation, dephosphorylation, and GTPase activities), and concentration of biomolecules.

Some common examples of FRET-based biosensor designs are illustrated below.
[Image: fretbiosensorsfigure1.jpg]

(a). Here, one of the FP is linked to the MRE and the other is linked to the analyte protein. When the sensory protein domain binds with the substrate, the donor and acceptor FPs are brought together, thus increasing the acceptor fluorescence intensity while reducing the donor fluorescence intensity. That is, according to this example, the fluorescence hue of the specimen changes from cyan to yellow. This strategy is commonly used to tag protein-protein interactions in live cells.

(b). In this type of biosensors, the donor FP and the acceptor FP are fixed to the opposite ends of the MRE. When the analyte binds to the MRE the conformation of the sensor protein changes thus placing the donor and acceptor FPs side by side. This increases the FRET efficiency. This is usually used for the detection of glucose, maltose, glutamate and cyclic nucleotides.

©. Two FPs are attached to each end of a complex unit composed of a sensory domain linked to its binding substrate. When the sensory domain is stimulated by the analyte, it binds to the substrate protein inducing a large overall conformational change that changes the FRET signal. Ca2+ biosensor that employ calmodulin as the substrate and calmodulin-binding peptide as the MRE is a classic example for this. When the calcium ion concentration is high, calmodulin binds to the MRE, bringing ther FRET pair closes and produces a FRET signal. When the calcium ion concentration drops below a certain level, calmodulin dissociates from the peptide, decreasing FRET.

(d) This model of biosensors is used to detect proteolytic activity. MRE, a substrate for the protease of interest, is cleaved by the enzyme thus detaching the FRET pair and this turns the FRET signal off.

Check out this link for an interactive flash tutorial on FRET-Based biosensors.

Bimolecular Fluorescence Complementation (BiFC)-based biosensors

In this type of biosensors, the FP which is split up and MRE is linked to one portion while the analyte protein is linked to the other portion. When the two proteins interact, the two fragments fuse together, refolding properly into its 3-D structure and produce a fluorescence signal. . BiFC biosensors are commonly used to detect protein-protein interactions in cells. It is even possible to combine pieces of different fluorescent proteins together thus producing chimeral FPs with a variety of fluorescent shades enabling the simultaneous study of multiple protein interactions in the same cell.

[Image: image2.jpg]

Single FP based biosensors

A single fluorescent protein coupled with a MRE makes up single FP based biosensors. The MRE can be either exogenous or endogenous. Analyte binding to the MRE causes conformational changes of the fluorescent protein consequently altering its fluorescent properties. This strategy is useful in pH sensitive biosensors, Zn2+ biosensors etc.

[Image: b907749a-f5.gif]

Crossbreeds

However, recent research advancements have resulted in biosensor designs that combine two or more of the above strategies.

A growing field

Owing to the comparative advantages such as ease of manufacture using standard molecular biology techniques, ability to noninvasively observe biological process in the live cells, high sensitivity, high selectivity, the progress in the development of the genetically encode fluorescent protein-based biosensors has been revolutionary.

Biotechnology Competitive Exams in India

0
0
Most of the undergraduate students in Biotechnology, in India, remain confused/anxious about their prospective careers in immediate future. Citing the lack/limit of the job availability in the Biotechnology industry for the fresh graduates (BSc/B.Tech), almost every fresher tries to procure a higher degree in the field to have an added advantage and increased opportunity for obtaining a job. Whereas, there's no comparison to the higher degree obtained from the foreign institutes/universities of repute, not everyone is able/affords to pursue the same. So, the truth is that, most of them end up obtaining the Masters/Phd from some Institute/University in India itself; and the plight becomes sad, when they obtain it from a low key private institute, further amplifying the woes of their career!

It was the impact of such facts that I got motivated to write an article for you all, which could amass most (if not all) of the information on revered Competitive Exams in India, that could help you obtain a standard Masters/PhD degree from an institute of repute in India, thus adding to the hopes of having a safe/secured future. Following is the compilation of the important Biotechnology Competitive Exams in India:

A. GATE BT/XL
The Graduate Aptitude Test in Engineering (GATE), in the subjects of Biotechnology (BT) and(Or) Life Sciences (XL) is the most famous competitive Exams in India for a bright Masters/PhD degree from the most revered institutes of the country i.e IITs, IISc, NITs, BITS.

Application Starts: September-October Every Year

Deadlines for form Submission: September-October Every Year (Only one month is given after the start date)

Eligibility: Final year graduation students and post graduate students

Exam Date: Second sunday of February (Commonly). Though it was held in January, for the first time in 2013.

Results: March 15 every year

From 2013, GATE is free for Females, while the application fee is around Rs 1000-1200 for males.

Details on GATE


B. CSIR UGC NET Life Sciences
One of the oldest examination system by Department of Science & Technology, Govt of India, CSIR UGC NET is the ticket to being a certified Lecturer/Research Scholar in any institute of repute/CSIR Lab in India. Even IITs/NITs/BITS/IISc accept their score for PhD admissions. Most CSIR Labs in the country prefer CSIR JRFs for the Research Associate posts/PhD admissions.

Application Starts: Twice every year (In February for June Exam) (In August for Dec Exam)

Deadlines for form Submission: (March and September)

Eligibility:B.Tech (final year) and Masters students (Not for BSc students, but BS-MS/MSc integrated students can apply after 10+2+3 year education completion for RA category.)

Exam Date: June and December every year

Results: August and February

Application Fee: Rs 400/- for General Candidates

Details on CSIR UGC NET


C. BET DBT JRF Exam
Junior Research Fellowship Exam, for admission in PhD in "any" government insititute/university in India, organized by Department of Biotechnolgy, Govt of India by the name of Biotechnology Entrance Test (BET) is one of the high class Biotech Competitive Exams in India (but sadly most students are unaware of it's value!). It shortlists 275 students, first 100 among whom are allowed to pursue PhD in any Insititute/University in India, while rest 175 are allowed the option of PhD from a list of DBT funded insitutes (which covers top 7 IITs!).

Start of Application: Last week of February

Deadline: Last week of March

Exam Date: 3rd week of April

Eligibility:Those who have passed after January 1 of 'Before Exam Year' or will appear
(till August of Exam Year) for Masters in Biotechnology Related Branches and B.Tech Final Year Students

Result: Mostly 10th of May

DBT JRF BET Details


D. CEEB by JNU
Combined Entrance Examination for Biotechnology (CEEB), is another Nationwide Biotech. Exam organized by JNU every year for admission to M.Sc and M.Tech Biotechnology programme in various participating Universities:
Participating Universities for MSc:
University of Allahabad, Allahabad; Annamalai University, Tamil Nadu (M.Sc in Marine Biotechnology); Baba Ghulam Shah Badshah University, Rajouri (J&K) (M.Sc in Bioresources Biotechnology); Banaras Hindu University, Varanasi; University of Burdwan, Burdwan; University of Calicut, Kerala; Devi Ahilya Vishwavidyalaya, Indore; Goa University, Goa (M.Sc in Marine Biotechnology); Gulbarga University, Gulbarga; Guru Jambheshwar University of Science and Technology, Hisar; Guru Nanak Dev University, Amritsar; Himachal Pradesh University, Shimla; HNB Garhwal University, Garhwal; University of Hyderabad, Hyderabad; University of Jammu, Jammu; Jawaharlal Nehru University, New Delhi; Kumaun University, Nainital; University of Lucknow, Lucknow; Madurai Kamaraj University, Madurai; Maharshi Dayanand University, Rohtak (M.Sc in Medical Biotechnology); MS University of Baroda, Vadodara; University of Mysore, Mysore; University of North Bengal, Siliguri; North Eastern Hill University, Shillong; Pondicherry University, Pondicherry; University of Pune, Pune; RTM Nagpur University, Nagpur; Sardar Patel University, Gujarat (M.Sc in Industrial Biotechnology); Shivaji University, Kolhapur (M.Sc in Environmental Biotechnology); Tezpur University, Tezpur (Assam) (M.Sc in Molecular Biology and Biotechnology); TM Bhagalpur University, Bhagalpur; Utkal University, Bhubaneswar; Veer Bahadur Singh Purvanchal University, Jaunpur; Visva-Bharati University, Santiniketan.

Participating Universities for M.Tech:
Anna University Chennai, Cochin University of Science & Technology, Kochi, Kerala, West Bengal University of Technology, Kolkata.

Application Starts: February

Application Deadline: March

Eligibility: For MSc.: Bachelor’s degree under 10+2+3 pattern atleast under Biological/Physical/Veterinary Sciences. BDS/MBBS/Engineering Students also eligible.
For M.Tech: Final year B.Tech Students

Exam Date: 3rd Week of May

Result: 2nd/3rd Week of June

Application Fee: Rs 600/- for General Category
CEEB JNU MSc Details


CEEB JNU M.Tech Details


E. ICMR JRF Exam:
Indian Council For Medical Research (ICMR) holds ICMR JRF exam every year to select 150 candidates, out of which 120 students are offered PhD admission in the field of biomedical sciences with emphasis on Life Sciences (like microbiology, physiology, molecular biology, genetics, human biology, bioinformatics, biotechnology, biochemistry, biophysics, immunology, Pharmacology, zoology, Environment Science, botany, veterinary sciences, bio-informatics etc.) and 30 are offered PhD in field related to Social sciences like psychology, sociology, home science, statistics, anthropology, social work and Health Economics, from a medical college / hospital / university / national laboratory / institution of higher learning and research that comes under ICMR support, amongst which AIIMS is the most popular name!

Application Starts: March End

Application Deadline: April End

Eligibility: M.Sc/M.A or equivalent degree (B.Tech included)

Exam Date: July 2nd Week

Results: September

ICMR JRF Details


F. Other Important Exams:

1. RGPV PhD Exam

2. VITMEE

3. CSIR PGRPE

4. University of Pune

5. University of Mumbai

6. Delhi University

7. SHIATS Allahabad

8. HBTI and GBTU

9. Delhi Technical University

10. Punjab Agricultural University

So, this was a compilation of major Biotech Entrance Tests in India. I hope this information helps you in procuring a standard higher degree in Biotechnology.

Best Wishes!

Use of Algae through different approaches

0
0
INTRODUCTION:

It seems probable that growth in human population, future climate change effects on freshwater resources, which are already stressed in some regions and eventual shortages of unutilized arable land will encourage the exploitation of microalgae based production systems for both food and fuel. Claims that the ability to utilise non-arable land and waste water resources with few competing uses make algal biofuel production systems superior to biofuels based on terrestrial biomass has created great interest in governments, NGOs, the private sector and the research community. Current initiatives clearly indicate this interest at all levels of government and the in private sector in the development of algal biofuels technologies and enterprises. Microalgae are one of the most important bioresources that are currently receiving a lot of attention due to a multiplicity of reasons. The world is faced with energy challenges in the near future and it is reported that fossil fuel reserves will be depleted in half a century . This will be an unprecedented vicissitude that will impact negatively on all anthropogenic activities most importantly agriculture, industry and commerce. With this in mind, it is crucial to explore renewable and cost-effective sources of energy for the future. It has been estimated that biomass could provide about 25% of global energy requirements and can also be a source of valuable chemicals, pharmaceuticals and food additives.

In addition, the growing of urban population poses a serious threat to the environment due to the release of copious amounts of domestic municipal wastewater. The use of microalgae is desirable since they are able to serve a many role of bioremediation of wastewater, generating biomass for biofuel production with concomitant carbon dioxide sequestration. In addition, wastewater remediation by microalgae is an eco-friendly process with no secondary pollution as long as the biomass produced is reused and allows efficient nutrient recycling. As the demand for energy continues to increase globally, fossil fuel usage will likewise continue to rise. There is still a plentiful supply of fossil fuels at reasonably low cost, although this is likely to change in the future, but more critically a rising use of fossil fuels is unlikely to be sustainable in the longer term principally due to the attributed increase in greenhouse gas (GHG) emissions from using these fuels and the environmental impact of these emissions on global warming. There is therefore significant interest in identifying alternative renewable sources of fuel that are potentially carbon neutral. Biofuels derived from the cultivation of algae have therefore been proposed as an alternative approach that does not impact on agriculture. Microalgae cultivation using sunlight energy can be carried out in open or covered ponds or closed photobioreactors, based on tubular, flat plate or other designs. Microalgae production in closed photobioreactors is highly expensive. Closed systems are much more expensive than ponds. However, the closed systems require much less light and agricultural land to grow the algae. In order to have an optimal yield, these algae need to have CO2 in large quantities in the basins or bioreactors where they grow. Thus, the basins and bioreactors need to be coupled with traditional thermal power centers producing electricity which produce CO2 at an average tenor of 13% of total flue gas emissions. The CO2 is put in the basins and is assimilated by the algae. It is thus a technology which recycles CO2 while also treating used water. Use of biodiesel from oilgae is a promising alternative to solve air pollution problems. Algae-based technologies could provide a key tool for reducing greenhouse gas emissions from coal-fired power plants and other carbon intensive industrial processes. To achieve environmental and economic sustainability, fuel production processes are required that are not only renewable, but also capable of sequestering atmospheric carbon dioxide (CO2). Second generation microalgal systems have the advantage that they can produce a wide range of feedstocks for the production of biofuels. Biodiesel is currently produced from oil synthesized by conventional fuel crops that harvest the sun’s energy and store it as chemical energy. This presents a route for renewable and carbon-neutral fuel production. However, current supplies from oil crops and animal fats account for only approximately 0.3% of the current demand for transport fuels. In 2008 the world production of biodiesel fuel was about 13.9 million ton [48-52]. In addition, these photosynthetic microorganisms are useful in bioremediation applications. The advantages of using microalgae for biodiesel production cannot be overemphasized. Biodiesel can be generated from 0306-2619/$ crops such as sugar cane, soybean, canola, rapeseed, maize, olive oil, non-edible jatropha, inter alia. However the use of food crops for biofuels has generated much debate involving food security concerns. The main advantages of using microalgae as a source of biomass for biodiesel production are: high growth rates and short generation times, minimal land requirements, high lipid content, use of wastewater stream as nutrient feed with no need for chemicals such as herbicides and pesticides.

II. MULTIPLE ROLES OF MICROALGAE
There is several utilization of algae or microalgae by which we can sort out the environment problems like; the major problem of global warming is CO2 in the atmosphere which creates green house effects, so for the growth of microalgae the utilization of CO2 is very essential, and to generates around 1 kg algal biomass requires 1kg of CO2 which is better to sort out this problem, it can be reduce many heavy or toxic metals form waste water and this process called Phycoremediation, It can be use as biofuel to reduce the effect of our conventional fuel which is going to be finish day by day because algae have potential to produce biofuel in the form of lipid which id further processed by transesterification process get the biodiesel which has the properties same as the our conventional diesel and it can be use for the many cosmetics, food and many use in the field of pharmaceuticals.


A. Phycoremediation
Phycoremediation may be defined in a broad sense as the use of macroalgae or microalgae for the removal or biotransformation of pollutants, including nutrients and xenobiotics from wastewater and CO2 from waste air with concomitant biomass propagation. There are numerous processes of treating water, industrial effluents and solid wastes using microalgae aerobically as well as anaerobically. Remediation is generally subject to an array of regulatory requirements, and also can be based on assessments of human health and ecological risks where no legislative standards exist. Recent studies have shown that microalgae can indeed support the aerobic degradation of various hazardous contaminants. The mechanisms involved in microalgae nutrient removal from industrial wastewaters are similar to that from domestic wastewaters treatment. Phycoremediation comprises several applications: (i) nutrient removal from municipal wastewater and effluents rich in organic matter; (ii) nutrient and xenobiotic compounds removal with the aid of algae-based biosorbents; (iii) treatment of acidic and metal wastewaters; (iv) CO2 sequestration; (v) transformation and degradation of xenobiotics; and (vi) detection of toxic compounds with the aid of algae-based biosensors. Nutrient removal with the aid of microalgae compares very favourably to other conventional technologies.

The growth of microalgae is indicative of water pollution since they respond typically too many ions and toxins. Blue-green algae are ideally suited to play a dual role of treating wastewater in the process of effective utilization of different constituents essential for growth leading to enhanced biomass production. The release of free oxygen is of major significance in organically enriched wastewater, promoting aerobic degradation processes by and other microorganisms. Secondly the role of microalgae is the accumulation and conversion of wastewater nutrients to biomass and lipids.

The capability of microalgae to degrade hazardous organic pollutants is well known. Chlorella, Ankistrodesmus and Scenedesmus species have been already successfully used for the treatment of olive oil, mill wastewaters and paper industry wastewaters. One way to investigate the capability of algae to biodegrade organic pollutants in municipal waste is to encourage the cells to grow in the presence of the pollutants and findings showed that both cyanobacteria (blue-green algae) and eukaryotic microalgae were capable of biotransforming naphthalene to four major metabolites, 1-naphthol, 4-hydrox-4-tetralone, cis-naphthalene dihydrodiol and trans-naphthalene dihydrodiol at concentrations which were non-toxic. The biomass resulting from the treatment of wastewaters can be easily converted into added value products. Depending by the species used for this purpose, the resulting biomass can be applied for different aims, including the use as additives for animal feed, the extraction of added value products like carotenoids or other bio-molecules or the production of biofuel.

The mass production of algae has historically been for use as a food supplement or wastewater treatment. The technology for production of biomass from wastewater has been present since the 1950s. Microalgae are efficient in the removal of nutrients from wastewater. Thus many microalgal species proliferate in wastewater due to the abundance of carbon, nitrogen and phosphorus that act as nutrients for the algae. Unicellular algae have shown great efficiency in the uptake of nutrients and have been found to show dominance in oxidation ponds. Application of using wastewater for the production of biomass however, occurs only on a minor scale and generally in the form of waste stabilization ponds or high rate algal ponds for the treatment of wastewater. Production of biomass from wastewater requires, similar production of biomass on artificial media, depends on a number of factors. However factors of heavy metal contamination require greater attention than in conventional production from media. Park et al. has recorded the following to be desirable attributes of microalgal species for use in High rate algal ponds (HRAPs), (1) High biomass productivity when grown on wastewater, (2) tolerances to seasonal and diurnal variation in outdoor conditions, (3) form aggregates to enhance ease of harvesting, (4) accumulation of high amounts of lipid or other valuable products. This suggests the potential of lowering the cost of algal biofuels production, which is currently not economically feasible.

B. Wastewater treatment methods
An understanding of the nature of wastewater is essential in the design and operation of treatment processes. Disposing of liquid and solid waste in rivers, streams, lakes and oceans seemed convenient for mankind. The quantities of wastewater at any point may ‘‘over load’’ the bio-system disrupting the natural recycling processes such as photosynthesis, respiration, nitrogen fixation, evaporation and precipitation. Wastewater treatment is an important initiative which has to be taken more seriously for the betterment of society and our future. Wastewater treatment is a process, where contaminants are removed from wastewater including domestic wastewater, to produce waste stream or solid waste suitable for discharge or reuse. Domestic wastewater is a combination of water and other wastes originating from homes, commercial and industrial facilities, and institutions. Untreated wastewater generally contains high levels of organic material, numerous pathogenic microorganisms, as well as nutrients and toxic compounds. Disposal of municipal solid wastes (MSW) in sanitary landfills is usually associated with soil, surface water and groundwater contamination when the landfill is not properly constructed. It thus entails environmental and health hazards, consequently, must immediately be conveyed away from its generation source(s) and treated appropriately before final disposal. The ultimate goal of wastewater management is the protection of the environment in a manner commensurate with public health and socio-economic concerns. Biological treatment is an important aspect of industrial and municipal wastewater treatment and reuse processes. Wastewater treatment methods are broadly classified into three categories; there are physical, chemical and biological. Among the first treatment methods used were physical unit operations, in which mechanical forces are applied to remove contaminants. Today, they still form the basis of most process flow systems for wastewater treatment. Chemical processes used in wastewater treatment are designed to bring about some form of change by means of chemical reactions. They are always used in conjunction with physical unit operations and biological processes. In general, chemical unit processes have an inherent disadvantage compared to physical operations in that they are additive processes, since there is usually a net increase in the dissolved constituents of the wastewater. This can be a significant factor if the wastewater is to be reused.

It has been appreciated for some years now that microalgae can be potentially utilized for low cost and environmentally friendly wastewater treatment compared to other more commonly used treatment processes. The selection of microorganisms for use as alternative fuel sources requires a sustainable growth medium such as domestic wastewater streams. The majority of wastewaters contain very high concentrations of nutrients, particularly total N and total P concentration as well as toxic metals, so there is no requirement for costly chemical-based treatments. According to de la Noue et al. the concentration of total N and P can be found at values of 10–100 mg L-1 in municipal wastewater and >1000 mg L-1 in agricultural effluent. Microalgae have potential to treat wastewater by efficiently accumulating nutrients and metals from the wastewater. Sustainable low cost wastewater treatment has been strongly proven by using microalgae. Microalgae grown on wastewater for energy production have been proposed for a long time. However, in recent years, microalgae seem to be a favorite candidate for this purpose, due to their ease of cultivation and the favourable possibility of their use as an alternative biomass for bioenergy production. Increase in global warming, depletion of fossil fuel and the need for mitigation of green-house gas (GHS) emissions; make exploration of the feasibility of biological wastewater treatment .


C. Algal biofuels
Algae, particularly green unicellular microalgae have been proposed for a long time as a potential renewable fuel source. Microalgae have the potential to generate significant quantities of biomass and oil suitable for conversion to biodiesel. Microalgae have been estimated to have higher biomass productivity than plant crops in terms of land area required for cultivation, are predicted to have lower cost per yield, and have the potential to reduce GHG emissions through the replacement of fossil fuels.

As with plant-derived feedstocks, algal feedstocks can be utilized directly or processed into liquid fuels and gas by a variety of biochemical conversion or thermochemical conversion processes. Dried algal biomass may be used to generate energy by direct combustion but this is probably the least attractive use for algal biomass. Thermochemical conversion methods include gasification, pyrolysis, hydrogenation and liquefaction of the algal biomass to yield gas- or oil-based biofuels. Biochemical conversion processes include fermentation and anaerobic digestion of the biomass to yield bioethanol or methane. In addition, hydrogen can be produced from algae by bio- photolysis. Finally, lipids, principally triacylglycerol lipids can be separated and isolated from harvested microalgae and then converted to biodiesel by transesterification.

The potential for sustainable biofuel production One of the attractions of microalgae as a biofuel feedstock is that they can be effectively grown in conditions which require minimal freshwater input unlike many plant-based biofuel crops, and utilize land which is otherwise non-productive to plant crops, thus making the process potentially sustainable with regard to preserving freshwater resources. For example, microalgae could be cultivated near the sea to utilize saline or brackish water. There has therefore been significant interest in the growth of microalgae for biofuels under saline conditions. However, another potentially sustainable growth medium for algal feedstock is wastewater. It has been appreciated for some years now that microalgae can be potentially utilized for low-cost and environmentally friendly wastewater treatment compared to other more commonly used treatment processes.

D. Biodiesel from oilgae
Biodiesel is a biofuel commonly consisting of methyl esters that are derived from organic oils, plant or animal, through the process of transesterification.

An excess of methanol is used to force the reaction to favor the right side of the equation. The excess methanol is later recovered and reused. Biodiesel has received much attention in recent years. Biodiesel is the best candidate for diesel fuels in diesel engines. Biodiesel burns similarly to petroleum diesel as it concerns regulated pollutants. On the other hand biodiesel probably has better efficiency than gasoline. Biodiesel fuel has better properties than petro-diesel fuel; it is renewable, biodegradable, non-toxic, and essentially free of sulfur and aromatics. Typical raw materials of biodiesel are rapeseed oil, soybean oil, sunflower oil and palm oil. Beef and sheep tallow and chicken fat from animal sources and cooking oil are also sources of raw materials. Commonly accepted biodiesel raw materials include the oils from soy, canola, corn, rapeseed, and palm. New plant oils that are under consideration include mustard seed, peanut, sunflower, and cotton seed. The most commonly considered animal fats include those derived from poultry, beef, and pork. Serious problems face the world food supply today. Food versus fuel is the dilemma regarding the risk of diverting farmland or crops for liquid biofuels production in detriment of the food supply on a global scale. Biofuel production has increased in recent years.

E. Biofixation of carbon dioxide by microalgae
Biofixation of CO2 by microalgae mass cultures represents an advanced, climate friendly biological process that enables the direct utilization of fossil CO2 streams produced from concentrated sources. Mitigation of GHG emissions would result from the conversion of the algal biomass to renewable biofuels [56,45,52 and 69]. Fossil-fuel-fired power plants contribute approximately one third of the total human-caused emissions of CO2. Fossil fuels will remain the mainstay of energy production well into the 21st century. However, increased concentrations of CO2 due to carbon emissions are expected unless energy systems reduce the carbon emissions to the atmosphere. To stabilize and ultimately reduce concentrations of the CO2 gas, it will be necessary to employ carbon sequestration – carbon capture, separation and storage or reuse. Carbon sequestration, along with reduced carbon content of fuels and improved efficiency of energy production and use, must play major roles if the nation is to enjoy the economic and energy security benefits, which fossil fuels brings to the energy mix. The availability of a carbon dioxide fixation technology would serve as insurance in case global warming causes severe restrictions on carbon dioxide emissions. Integrated processes in wastewater treatment and aquaculture were indicated as near-term applications of this technology. Microalgae applications in greenhouse gas mitigation could come through the development of wastewater treatment and aquaculture processes that combine their waste treatment features with reduction in greenhouse gas emissions and biofuels production. The greatest potential for microalgae biofixation processes is in developing countries, which should be included in any future development of this technology. The ultimate objective of microalgae biofixation of CO2 is to operate large-scale systems that are able to convert a significant fraction of the CO2 outputs from a power plant into biofuels. Biofixation of CO2 using photosynthetic organisms has been looked at as a way to stop or slow down the effects of global warming.

.docx  biotech.docx (Size: 23.01 KB / Downloads: 2)

Indian Biotechnology Companies And Their Job Openings

0
0
Biotechnology in India has remained in infant stage for over a decade. Though the institutional research in Biotechnology never ceased to happen, the job prospects in this industry have only followed a downward trend. Much of it might be attributed to the flooding numbers of Biotechnology graduates/postgraduates every year, with no increase in demand at the level of limited number of "good" Biotechnology Companies. Under such a scenario, any lack of enthusiasm and determination to move against the odds can prove fatal for the future. Jobs are always there for the deserving, bright candidates, but for that one needs to search them actively and apply to the company concerned, within stipulated time to make a mark! So, here in this article, my focus is on enlisting some of the companies of repute in India, which are actively pursuing "good" candidates:

1. Biocon
It's the dream destination for most Biotechnology professionals. Ranked among the Top 20 best Biopharma Employers Globally, Biocon can change the entire anatomy of one's struggling career!
Click Here to goto Biocon Career Section


2. Dr. Reddy's
Another Global Pharma giant! working on Pharmaceutical Services and Active Ingredients, Global Generics and Proprietary Products.
Click here to goto Dr. Reddy's Openings


3. Wockhardt
Another Global Biotechnology Organization manufacturing high quality therapeutic drugs.
Click here for Wockhardt's Openings


4.Himalaya Drug Company
The products of this company have been a household name since decades. They work on a variety of products ranging from Pharmaceuticals, Personal Care, Animal Heath to Nutrition!
Click here for Himalaya Drug Company's Openings


5. Pfizer
Amongst the world's best research based pharma giant, Pfizer works on discovering, developing, manufacturing, supplying and consulting in pharmaceuticals.
Click here for Pfizer Openings


6. Novozymes
They are one of the globe's major enzyme solution providers along with other biotechnological domains.
Click here for Novozymes Openings


7. Praj Industries
Praj is an innovation driven Indian green technology provider with two major thrusts: entire value chain in Bioethanol and Waste water treatment. Their innovative fermentation techniques and expertise has caught the attention of the industry and research, making them a sought after company both for job seekers and outsourcers.
Click here for Praj Opportunities


8. SRL Ranbaxy
Not an alien name for any biotechnology student/professional. They are one of the famous recruiters of freshers.
Click here for SRL's Openings


9. Cadila Pharmaceuticals
Cadila is a well renowned drug manufacturer in the country. It looks for experienced professionals.

Click here for Cadila Openings


10. Panacea Biotech
A popular research based health management company, it has various openings in variety of domains.
Click here for Panacea Openings

Click on the various domains enlisted on the left side of the page (which opens on clicking the above link), to view the job openings in the domain of interest. The above mentioned link will open the QA/QC domain jobs.

11. Bharat Biotech
An enterprise of Dr. Krishna Ella, it's an emerging healthcare solutions provider.
Click here for Bharat Biotech Openings


12. Yashraj Biotechnology
Another emerging private enterprise, actively searching for new talents to hire:
Click here for Yashraj Openings


13. Asterazeneca
A subsidiary of HCl and now collaborated with TCS, Asterazeneca is a leading pharmaceutical company.
Click here for Asterazeneca Openings


14. Nestle
A household name in entire world. It's a leading food products manufacturer. A frequent recruiter of freshers for the post of Nutrition Officers.
Click here for Nestle Openings


15. Glaxo-Smith-Kline
One of the oldest pharmaceutical companies in India, GSK is a world renowned research-based healthcare and pharmaceutical company.
Click here for GSK Openings


These were some of the major and active Pharma/Biotech recruiters in the country. The list includes the names of the well renowned companies in India and across the globe with special emphasis on those with current open positions. The actual number of Pharma/Biotech companies are so many in number that they cannot be included in a single article (One can rather write a directory on the same!). Following is a list (with links) of some other Biotechnology companies, which pursue new talents (though less actively). There are high chances of procuring a summer internship though in the below mentioned institutes. Nevertheless, one shouldn't ignore these companies either, for these days opportunities have to be knocked out, than to wait for them to knock at your door!

a. Ajanta Pharma

b. Concord Biotech

c. Claris Life Sciences

d. Danisco-Dupont

e. Amrutanjan

f. Biotron Healthcare

g. Gujarat Narmada Valley Fertilizers & Chemicals Ltd

h. Shantha Biotech

i. Baxter

j. Emcure Pharma

Again, the list is not exclusive/exhaustive! It will be updated whatever/whenever new information is researched/received! Till then, I hope this information adds some relief to the anxious nerves.

Thanks and Best Wishes!
Viewing all 2695 articles
Browse latest View live




Latest Images