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Application and Importance of Biotechnology

February 9, 2013, 12:45 am
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Since the DNA of all living organisms has the same structure either in terms of people, plants, animals or micro-organisms, some of its parts (genes) can be cut and transported from the cells of an organism to another cell without much trouble. New DNA is called recombinant DNA, and these manipulations are based on biotechnological processes.

In this way it is possible to insert individual genes or groups of genes in different receptors and thereby enhance the features or lead to the production of new proteins and the development of entirely new traits.

Getting Recombinant DNA

Some of these procedures has opened a number of possibilities and applications in various fields. Similar methods are applied in the production of the controversial genetically modified foods, with inserting of foreign genes performed in order to improve product quality, increase resistance to disease and parasites, and many other features.

Various biotechnological methods are also used in the production of new vaccines in veterinary medicine, as well as the measures of biological control of weeds and pests.
Certainly the most promising applications of biotechnological advances is in medicine where are the greatest investments and expectations. Biomedicine is the application data and the results obtained in biotechnological research in medicine with the goal of getting new drugs and the development of new therapies that unlike the current will be directly designed in accordance with the genetic code of the individual.

Knowledge of the genetic code will help much more quickly and easily isolate individual genes and their protein, and to determine their roles. The results should first be felt in the diagnosis. That means it will be possible to diagnose the disease early while the drugs be adapted to each individual, and this way they will be more accurate and more effective. "We will develop a different drug, although we can not expect that to happen very quickly. It willl be very difficult to correct gene, but over the next decade we expect that it will become possible," said dr. John Sulston, a British researcher in the Human Genome Project.
Maps genes should help in the detection of hereditary disorders, prevention of disease and treatment. Special attention is given to the development of gene therapy in which defects caused by mutations in a gene, tries to correct by entering the correct gene in the organism.

Knowledge of the genome will allow scientists around the world to explore the genetic bases of diseases involving disruption of several genes, such as diabetes, cancer and Alzheimer's disease.

Genome Research

This research includes systematic investigation of the genome, or complete chromosome sets of a particular organism. At present such research includes the creation and use of large databases, expensive and sophisticated laboratory equipment and also heavily invested in the research.
There are two aspects of genome research - structural and functional.

Structural testing is the determination of DNA sequences and gene mapping.

Functional testing is focused on the functional activities of established genetic sequences. How to be coming to an end of reading the human genome, and this way focus will be shifted from structural to functional aspects of the research, with the aim of obtaining specific results applicable in practice.

Protein Research

Identification of all the proteins in the cells and analysis of their interactions are currently one of the most attractive fields in the biotechnology industry, both in large companies and in companies in the establishment.
Proteome name was established in 1994 when it was Mark Willkins doctoral student at the University of Sydney, first used to describe the set of all human proteins. Proteins are the "worker" cells and potential targets for drugs. However, identification and sequencing of the gene does not currently provide sufficient information for the development of new therapies.

There was developed a new field of proteomics research that deals with research of protein structure and their interrelationships. This area is becoming more attractive for investment. Only from June 2000 to October 2001, more than $ 700 million investor 'capital is invested in companies involved in examining the proteome.
After the publication of the first complete analysis of the human genome biomedical research will be almost completely transferred from genomics on proteomics as a key technology to transform information into pharmaceutical products. The need to improve the speed and efficiency of finding new drugs will be the primary guiding principle in these investigations. Current methods of gradual and chemical methods have been optimized long time (an average of 10-12 years to detect new drug) and expensive (an average of 500-750 million U.S. dollars). There is also a high percentage of failure in clinical trials because of toxicity or low efficacy of potential new drugs, resulting in a growing interest in bio-markers are suitable for use in therapeutic planning and design personalized medicines.

For proteomic industry is projected to rise from 565 million U.S. dollars in 2001 to over 3.3 billion U.S. dollars in 2008. This represents an average annual growth rate of 40% and it is expected that demand for proteomic products will be great during this time period. It is expected that the growth rate in this segment of the market will begin to decline until after 2008, when the next generation proteomic product is brought to market

Based on information obtained in the genomic and proteomic research over the next ten years is expected to be significant progress in the pharmaceutical industry. Determining targets for drugs within proteomic research would lead to a significant improvement and creation of such drugs to block exactly those proteins that cause certain diseases. In addition to improvements in laboratory tests are also expected to accelerate the procedure and performance of new drugs on the market.
Since this process is currently very slow and expensive, pharmaceutical companies would greatly reduce costs. Hundreds of millions of dollars are spent annually on research and development of new drugs. In fact only one of the 1000 experimental compounds pass preclinical testing, and one of five clinically tested drugs coming on the market.

Getting concrete information from the genetic code and discover the cellular mechanisms that lead to the formation of certain pathological conditions or disease outbreaks (especially when it comes to genetic disease), it could be a theoretical basis for the design of new, highly specific drugs that were in line with genetic code of the individual, and therefore much more effective than existing drugs. There are forecasts that sales of such drugs on the market could increase the revenues of pharmaceutical companies up to 50 percent or more.
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Sequencing the Human Genome

February 11, 2013, 3:32 am
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Launching the project

Sequencing the human genome project was launched in late 1990 in the United States by the National Institutes of Health (NIH) and the Department of Energy, it was very important project at that time.

Together with several centers around the world (Sanger Centre in Cambridge UK, Whitehead Center, RIKEN genomic center in Japan, the Max Planck Institute in Germany and other smaller centers in the U.S., Germany, France, Canada and China, and Japan), they have established an international consortium of university centers and began the Human Genome Project (HGP) - fifteen-year project to map about 100 000 genes of the human genome and that project worth was $ 3 billion.


The project was funded by the National Institutes of Health and the U.S. Department of Energy and the Wellcome Trust in the UK, and most of the research was done in the Sanger Centre in Cambridge, England and the Whitehead Center for Genome Research in the United States.
The main thing that the members of the International Consortium was set up then was sequencing the complete human genome (the process of determining the exact order of 3 billion nucleic bases which build DNA molecule) to 2008 year with the formation of public databases.

To make the data obtained in the most efficiently, the project has required an efficient distribution of information to make them available to researchers as quickly as possible in any point on the planet. Under the plan processed results from all centers that are involved in the project to sequence the genome of every day to will be published in public databases available over the Internet.


This project, although very ambitious, has attracted greater public attention until 1998 when Dr. Craig Vender left and formed a rival consortium of private company Celera Genomics, which has set a goal of sequencing the human genome in 2001.

Human Genome Project vs. Celera

Human Genome Project (HGP) and Celera researchers have used different strategies in their work on project, both during the sampling procedure and in sequence.
Human Genome Project researchers have been working on samples collected from multiple donors, while Celera researchers working on the samples collected from five anonymous donors, representatives of different ethnic groups, African-American, Hispanic, Asian and Caucasian (white).

The procedure sequencing of these two groups was also different between Human Genome Project and Celera. The scientists involved in the Human Genome Project have chosen a slower and more methodical approach. They divided the genome in 22,000 segments, each a debt of 100,000 to 300,000 base and map their exact positions.

These segments were then cloned and several clones encoded by the automated sequencer. The process was repeated several times to ensure accuracy of results.

This technique is more reliable and more able to spot mistakes but it is much slower than the techniques applied by Celera, so that slowness was the biggest flaw of this method.


Celera Genomics company began its project eight years later, when computers became more powerful and their approach was much faster and cheaper.

Scientist Mark Adams has developed an algorithm for the application of new technology sequencing (shotgun technique) and it is the first company used to map the genome of fruit flies (Drosophila melanogaster).
This method is the compled DNA (Deoxyribonucleic acid) cloned several times and then divided into 60 segments each measuring million from 2000 to 10,000 bases. Each fragment is encoded for myself and the results are automatically sent to a central computer Celerina. Computer task now was to reconstruct all 60 million decoded fragments of chromosome 23. Since a large part of the genome consists of highly repetitive sequences, this was the most controversial step in the methods of celery because it raised the subject of proper reconstruction and thus the credibility of the calculated data.

Results

Both groups have published the first results in February 2001 by a margin of just one day, it was some kind of race between this two. Human Genome Project has published the results of its journal Nature, Celera Genomics in the journal Science. Made detailed maps of parts of the genome will greatly facilitate further study of DNA. The consortium has announced that 88% of the genome sequenced to an accuracy of 99.99%, and by 2003 it is planned and the remaining portions of the genome sequencing in order to obtain a complete picture.

The question of which data are more accurate? Human Genome Project scientists believe that their information is accurate since the procedures were repeated five times unlike celery, which is a procedure repeated only three times. Representatives of celery of course have a different opinion, they think that even with three repeating thay made better results than Celera with five .

In any case, the fact is that the Celera process was somewhat eased the ability to compare their results with the results available to the public Human Genome Project.At this point the human genetic code is available on the internet. Human Genome Project data have been published publicly and can be used free of charge.

Celera did release some of data to the public, but most of the results are in Celera database for purpose of making profit, making posiblemaintenance requirements of the system, usually drug companies were clients, main clients.

The hardest part is yet to come though. In the final phase, researchers must identify each gene, its position on the chromosome and its function. Genetic sequence at this point is just a set of bare data and requires a lot of work to these genetic databases translate into applicable data.

In any case, the fact that a full understanding of the genetic material will not be possible for decades and when we can expect concrete results it is hard to tell, but predictions are that maybe in next few years there will be huge moves to resolving one of most important scientific secrets. In this moment we can say that both, Human Genom Project and Celera, working with different techniques on this project, made one of most important steps in researching DNA.
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Designer baby - Frequently Asked Questions

February 12, 2013, 11:51 am
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Hey I am male 25. I d love to have childs one day but I d give a lot to have them not suffer from any kind of diseases. g.e. I am badly short sighted and have acne. I know this multifactorial genes diseases genes are not known yet but I hope so.

What I really would love is some information on what is possible yet.

1) Its possible to eliminate bad genes out of male genom (sperms) before melting it together with female egg cell thats what I am pretty sure about.
2) Is it also possible to eliminate the females bad genes as far as they are known from the female egg cell ?
3) If yes it should be possible to create more or less life without any diseases as far as the "bad genes" are known.
4) What does it cost for a full human genome sequence currently ?
5) How much would it cost to check this genome of me and a female for any known genes that might cause a disease ?
6) Someone got websites where attractive and healthy females offer their egg cells ?
7) Where you might get a surrogate mother from ? any websites known ?

And please dont start a discussion about morality. I know what I want and I want to create childs without disease. Dont tell me thats bad. Dont tell me this will end like in the movie gattaca. In fact thats exactly what I am hoping for as far as the current technology can offer that yet.
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UWM is seeking testers for a new protein expression kit

February 15, 2013, 11:53 am
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Dr. M.L.P. Collins at the University of Wisconsin-Milwaukee has developed a new method for making large quantities of active, viable proteins using Rhodospirillum rubrum as a host. R. Rubrum is a bacterium that has traditionally been studied for its simple photosynthetic system, has demonstrated recent success in expressing high-yield protein.

To provide a brief overview, R. rubrum possesses the unique characteristic of forming an intracytoplasmic membrane (ICM) in response to membrane protein synthesis. The ICM is non-essential for growth and can incorporate foreign and over-expressed membrane proteins without disrupting normal cellular function. This characteristic has stimulated the expression of active and correctly folded membrane protein where other systems have failed.

In an attempt to gather additional testing data, the UWM Research Foundation would like to provide free protein expression kits to laboratories or universities that are having difficulties with their current method of producing large-scale proteins. Having limited resources, our researchers have only had the ability to test a number of proteins but thus far have seen exceptional promise. We currently have 8 other universities or companies using the new kit and are now ready to distribute to other participants. The link listed below provides a more detailed explanation of the testing process including the specific proteins currently being tested. You may also view Dr. Collin’s publication on her findings of using R. rubrum as a host. If you are interested in learning more about this new system or have any additional comments, you may email me at erichuhn@uwmfdn.org.




Testing Kit Link
http://www.uwmresearchfoundation.org/get...-2013.aspx



Dr. Collin’s Publication
Butzin, N.C; Owen, H.A.; and M.L.P. Collins. 2010. A new system for heterologous expression of membrane proteins: Rhodospirillum rubrum. Protein Expression and Purification, 70: 88-94.
http://www4.uwm.edu/letsci/biologicalsci...l_2010.pdf
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Life Without Pulse - Artificial Heart Implantation

February 16, 2013, 3:08 am
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Scientists are developing new strategies and methods every day to master key forces that humankind knows, which should fundamentally change our relationship to the previously unchangeable natural processes: treatment, aging, regeneration and dying.

With heart disease being the number one cause of death in the U.S., many people with heart disease die before heart donations become available to them. Thus, a huge demand exists to develop a fully functioning artificial heart.

Because of the small number of organ donors with intact hearth and long waiting times for surgery, the first successful transplantation or installation of "temporary artificial heart" was performed. Experts see this venture as a great improvement, and as an opportunity to help patients with many types of heart diseases waiting for regular heart transplantation.

The artificial heart is a prosthetic device implanted into the human body in order to replace biological heart. There are many types of artificial heart, of which the most important are two: TAH – Total Artificial Heart (completely replaces human heart) and CAD – Cardiac Assist Device (helps the function of biological heart).

The First Case

In Cambridge, at Papworth Hospital, forty-year old Matthew Green became the first person in the UK to receive a new type of "temporary artificial heart," according to the new methods and procedures. The first heart transplant in the United Kingdom was also performed in this hospital in 1979.

Mr. Matthew Green has had serious issues with his heart (diseased heart muscle of the right ventricle) that lead to arrhythmias (irregular heartbeat), possible heart failure and sudden death. After the operation, which lasted 6 hours, he was provided with mechanical heart and he was ready to go home very soon.

Technology of Artificial Heart Implantation

Mechanical artificial heart which was implanted to Mr. Green is used in cases where the patient has serious problems with his heart, and there are no possibilities to get new heart from a human donor for a long time.

The device replaces the work of heart chambers and heart valves, and allows normal circulation of blood in the patient’s body.

The device is not yet so perfect and small enough to easily replace the heart. It requires an external power source that weighs about 6 pounds and must be carried in backpacks or bags over the shoulders. This device is still much better than the previous version which required fixed (stable) power source from the electric net or from a large battery, so the patient had to stay in hospital.

The Operation

A team of doctors who performed the operation-transplantation had a special training before this surgery, in order to safely manage the whole operation.

After the operation, Mr. Steven Tsui, consultant cardiac surgeon and director of the transplant department of this hospital, said:

"At any time, at our hospital, there are about 30 patients on waiting list, waiting for a heart transplant from a donor. Due to an insufficient number of donors, as many as one third of patients have been waiting for surgery more than a year. Condition of our patient, Mr. Green, deteriorated quickly and therefore we talked to him about the possibility of obtaining and installing the equipment. Without installing this device, the patient would not be able to survive the period needed to obtain a suitable heart donor. "

"The surgery went extremely well and Mr. Matthew is recovering successfully. We expect he will be released from the hospital very soon, and will be able to do much more than before. This surgery will significantly improve the quality of his life until we find the proper heart transplant."

Patient’s Gratitude

In a statement issued at the hospital, Matthew Green thanked the staff: "Two years ago I was riding my bicycle nine miles to work and nine miles back every day, and when I was admitted to the hospital, I was barely able to walk a few meters. I’m really excited to get back home because I'll be able to perform daily activities that I have not been able to do for quite a while. Now I'll be able to play in the garden with my son and cook a meal for my family, until the conditions for transplantation appear... "

The Lack of Organ Donors

More than 5.7 million people in the US are living with chronic heart failure.
Heart failure is the primary cause of more than 55,000 deaths each year. About half of people who have heart failure die within 5 years of diagnosis. Heart failure costs the nation $34.4 billion each year. This total includes the cost of health care services, medications, and lost productivity. Those are just some of the facts to point out how important the development of artificial heart can be. For many of those patients, a heart transplant from a donor is the only way to survive 10 years or more.

Despite successfully performed operation (transplantation) artificial heart, people from the British Heart Foundation point out that this mechanical heart implantation is just a temporary solution and not an ordinary treatment and permanent solution for patients with heart failure.

The UK government is campaigning to increase the number of organ donors. One of the initiatives suggests the drivers to declare whether they, in case of an accident, agree or disagree to be donors of their organs, so that relevant data can be recorded in their driver's license.


Opinions

Professor Peter Vajsberg medical director of the British Heart Foundation, believes that, for patients with serious heart problems heart transplant is the only hope to live longer. Because donor hearts are not always available, the life of these patients is often compromised.

The professor also believes that this new solution of mechanical artificial heart will enable many patients to survive until a heart transplant period.

Previous solutions and versions of the artificial heart supported only left side of the heart, while the newer solutions help patients with any type of heart failure, thus creating the preconditions for a successful transplant.
Although today, the artificial heart is only a temporary solution, we have the reason to hope that it will become the main treatment for the patients with serious heart problems.
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The Most Fascinating Examples of Genetic Engineering

February 19, 2013, 4:35 am
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Cats that glow in the dark? It may sound like a bad science fiction movie, but they are around us for several years. Cabbage that produce scorpion poison? Another thing, when you next need a vaccine, a physician may prescribe a banana - do not be surprised.

These and many other genetically modified organisms exist today as a result of DNA hybridization technique that uses DNA material from different organisms to create a completely new combination of genes. Maybe you didn’t pay enough attention, but many of these genetically modified organisms are part of our everyday lives. Today, 45% of U.S. corn and 85% soybeans are genetically altered, while 70-75% of the food on the shelves in supermarkets contains at least one such ingredient.

Just take a look at some of the strangest products of genetic engineering that exist today. Keep in mind that this is only the beginning. Many other products are probably already on the way.

Cats That Glow in The Dark

South Korean scientists created in 2007 cat that glows in the dark using genetic engineering, then took her DNA, cloned it, and created a number of fluorescent kittens.

Here's how they did it: They took skin cells from Turkish Angora female cat (species that were originally tamed by Tatars, but was later transferred to Turkey and is now considered the country's national treasure), and using the virus they inserted the genetic code for the production of red fluorescent protein. Then they put genetically modified nuclei into eggs for cloning and such cloned embryos are returned to the donor cat. It thus became the surrogate mother's own clones.

What’s the point of creating pets that can serve as a night lamp, people will ask. "These are the sick scientists. They have nothing better to do, then acting God, "some will say. However, the possibility of implanting the fluorescent properties in the genetic code of animals is a precursor to the possibility of creating animals with human diseases caused by genetic disorders, such as hemophilia, Down syndrome, Prader-Willie Syndrome and Turner, and many others, in order to make their research and experimentation much easier. So this definitely has potential to be a major milestone in medicine and can save many lives in the future.

Ecopigs

Ecopig is the pig genetically modified for more efficient digestion of phosphorus. The swine manure is rich in phytates, one of the main forms of phosphorus storage in plants. Pigs, like all non-ruminants, are unable to digest phytate, so they excrete it in the basic form which is later used as fertilizer. This situation can cause problems, because this matter is, if it enters the water, causing the multiplication of algae to the point where those take enormous surface of lakes, using up all the oxygen, preventing the light to pass into the deeper parts, and thus indirectly killing all the wildlife that of ecosystem.

To prevent this serious problem, scientists have added E.Coli bacteria and DNA of normal mouse in pig embryos. This modification has a direct effect on the processing of phosphorus through the digestive tract of pigs - reduces the presence of phytate and phosphorus in the feces for up to 70%. Admittedly, these pigs will actually deserve the prefix “-eco”.

Plants Fighters Against Pollution

Scientists at the University of Washington were able to create genetically engineered poplar, which is able to clean up contaminated land by absorbing contaminants from groundwater through its root system, and then through a series of chemical reactions, turning it into harmless substances stored in the roots and leaves or released in gaseous form through pores in the environment.

In laboratory tests, those modified plants have been able to remove 91% of trichloroethylene (the most common groundwater contaminants) from aqueous solution. Plain poplar manages to remove only 3%. Good statistics, one must admit.

Toxic Cabbage

Toxic cabbage? Does not sound like something you'd like to see in your salad. However, not everything is the way it appears at a first glance. In fact, scientists have recently succeeded to transfer the gene that is responsible for creating the scorpion toxins to cabbage. Why? The aim is to limit use of pesticides, and at the same time to prevent the destruction of this vegetable by a centipede and similar pests.

These genetically modified Cabbage is creating scorpion poison powerful enough to kill the average centipede or insect as soon as it bites one leaf. Best of all is that this poison, carefully synthesized and changed, is not dangerous to humans.

Goats That Make a Web

Strong, stretchable spider web is one of the strongest natural materials, stronger even than steel. Theoretically, it could have wide use - from the production of artificial ligaments to the ropes for parachutes. If only we were able to produce it in sufficient quantities. Nexia Biotechnologies Company said it has a solution: goat milk contains proteins of spider web!

The researchers inserted the gene from spider DNA gene into goats’ DNA in such a way that it secretes in their milk the protein for building the net. This milk can be used to produce biosteel, material with characteristics similar to spider webs.

Previous attempts of this material have failed because it is extremely difficult to create long protein chains as found in nature. This technique works because the way mammals produce milk is very similar to the way a spider creates its network.

Commercialization of this process has the potential to improve the quality of life for many people.

Bananas Vaccines

There are indications that in the foreseeable future, people could be vaccinated against hepatitis B, cholera and similar diseases simply by taking bites of banana. Scientists have successfully created bananas, potatoes, carrots and tobacco with the characteristics of the vaccine, but they say that bananas are still the best "vehicle" for the drug.

When inserted into a young banana, the modified form of the virus quickly releases its genetic material and becomes the part of the plant cell. Along with the growth of the plant, its cells produce proteins of the virus, but they are not contagious and dangerous. When people eat pieces of such genetically modified bananas, full of viral proteins, their immune system begins to produce antibodies to fight the disease - just l
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Determination of Bacterial CFU Using 'Miles And Misra Technique'

February 20, 2013, 10:14 am
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Determining Bacterial CFU :
A technique used in Microbiology to determine the exact number of cfu that is colony forming units in a bacterial suspension or homogenate is known as The Miles and Misra Method. This is a type of surface viable count technique. In 1938 Miles and Misra invented this method. In this method, Miles and Misra used dilution of S.pneumoniae on blood agar plate.
To learn this technique completely, let us understand what is its pre-requirements of materials, its method, its advantages and disadvantages.

Material Pre-requirements:
• A calibrated automatic pipette or a dropping pipette , delivering drops of 20 μl.
• Sterilized nutrient agar plates
• Diluent of Phosphate Buffered Saline (PBS)
• Bacterial suspension or homogenate
• Laminar Air Flow Bench
• Filter Sterilized Isop-propyl alcohol

Method
• Serial dilution of the inoculums / suspension is done in which, the dilution of 1x suspension is added to 9x of diluent. In case of unknown sample quantity or unknown bacteria quantity, dilutions should be made to at least 10−8.
• The average of three plates is calculated. This is required to have greater assurance of results. All three plates are inoculated with each dilution.
• A 20 μl drop is absorbed in the plate after 15-20 minutes of continuous spreading by natural means or rotation of plates.
• All the plates are equally divided into up to eight sectors. Proper labeling of the plates are done to have traceability.
• In each sector, 1 x 20 μl of the dilution is dropped onto the surface of the agar and thus the drop spreads. It is important to avoid touching the surface of the agar with the any tool or even with pipette.
• The plates are kept upright to dry before inversion and incubation at 37°C for 18 – 24 hours.
• Each sector is observed for growth, luxurious grown will be observed at high concentrations over the area of the drop, or a large number of small colonies which are generally merged. Colonies are counted in the sector where the highest number of full-size discrete colonies can be seen.
• The following equation is used to calculate the number of colony forming units (CFU) per ml from the original aliquot / sample:
CFU per ml = Average number of colonies for a dilution x 50 x dilution factor.

Advantages
• This technique is faster than other methods.
• With this technique, less bacterial contamination occurs of the working surface.
• This technique is easy to process as compared to other techniques for determining colony forming units.

Disadvantages
• This technique required high skilled microbiologist to perform serial dilution and also the one who are expert in aseptic techniques.
• The rate of absorption of drops on to the surface of agar depends upon the environmental conditions like temperature and humidity.

Conclusion: Colony forming units’ determination is a skilled technique and the use of this method makes it simple by using sectors and other methods. Any bacteria when grows on nutrient agar, forms a visible colony. This colony is indication of growth of bacteria on to the agar surface. This growth of bacteria which is called as colony forming unit is generally an accumulation of generations of bacteria at certain locations on the nutrient agar surface.

The most important step in this method is uniform absorption of bacterial suspension on to the surface of agar media. Once this is done, the chance of cross contamination within the sectors is reduced. The critical step therefore is to ensure that the drops within the sectors do not cross the specified superficial lines. Once this step is over, the plates can be further kept as it is to reduce the chances of micro-droplets of suspension being transferred to other sectors. The inoculated plates are then kept in incubators in inverted condition. These incubators may be either walk in incubators or simple small incubators. Walk in incubators are generally used when the sample size is huge.

Once incubated in favorable growth conditions like temperature and humidity, the growth of bacteria occurs within 18-24 hours of incubation. The temperature used is 37 degree Celsius which is optimum temperature of wide range of bacteria. This temperature is very much near body temperature of human being. It is also observed that this is the adaptation of bacteria to 37 degree Celsius which was not always there. This is because; many of the bacteria can survive comfortably at lower temperature or sometimes at higher temperature than 37 degree Celsius.
Since 1938, this method is widely used in determining colony forming units of many microbial samples.
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Workplace Safety and the Role of Safety Officers

February 23, 2013, 12:56 am
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Safety officer is in charge of managing the health and safety necessities of the workplace. The importance of a health and safety officer is predominant in construction sites and industries as there are more chances of workplace disasters. A safety officer must possess a bachelor’s degree and he should mandatorily-attend the occupational health and safety training provided by the industry.

Health and safety officers are intended to inform the higher official about the health and safety problems faced by employees in the workplace. They have to propose innovative safety measure that can be implemented to safeguard the company from workplace accidents. Safety officer courses are designed to train them to ensure that the employees are working in a safe and healthy atmosphere. Employees, who are distracted by health and safety issues, tend to give less effort on their work and this will adversely affect the productivity of their output. A quality health and safety course will inform candidates about the latest technological advancements in the field of health and safety, which can be implemented into their workplace to assure proper safety for employees.

Safety officer course gives hands on experience to candidates on how to effectively-utilize safety equipments in the backdrop of a workplace accident. They also are trained in conducting investigations on the wake of an accident. Intense training and in-depth understanding about the health and safety requirements of workplaces is essential for becoming a successful safety officer. A certified safety officer course will equip the officer with all these qualities.
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How to control weeds?

February 26, 2013, 12:05 am
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How to control weeds? I have some idea. I like to share with all. All of us give our opinion as soon as possible

In ancient times, we had used some methods like panchakavya, organic manure to control weeds. Now our technology is well propped. Is any technique identify chemical compounds in panchakavya, organic manure etc.., Is that's identify chemical compounds manipulate through biotechniques? If manipulated, which technique is favor? What is he successful rate of this application? Please give your opinion as soon as possible

Thank you to all
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TIFR interview need suggestion

February 26, 2013, 12:21 am
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Hi all,
I have selected for interview in TIFR M.Sc & Int Ph.d Biologogy. Interview will be held on March 20th 2013. How was ur interview? What type of questions did they ask u? and what was the duration of interview. ? Please share ur experience here. Please reply as soon as possible
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Spare Parts for Human

February 27, 2013, 3:41 am
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More and more people in the world have artificial organs, thanks to bionics. Although progress has been fantastic, some parts of the body like the liver or lungs, are too complex to be copied using present-day technology.

Artificial organs are now a reality. Doctors, researchers and bio-engineers were able to make almost perfect replacement for parts of the human body. Hundreds of thousands of people have artificiall shoulders, knees or hips, toes or arms, arteries and skin, teeth and jaws, pancreas and kidneys, trachea, larynx, limbs, bones, eyes, etc...

Using these technological advances, the patients who have lost part of their body or some of their organs stopped functioning due to illness or injury, will again be able to live without assistance. According to Donald O'Neill, vice president of one of the largest pharmaceutical companies, "Warner - Lambert" scientists will soon be able to replace every human organ. Bionic men from science fiction movies are slowly becoming a reality. These bionic organs are going to be developed as a result of united efforts of several scientific disciplines: Polymer chemistry, microelectronics, engineering and molecular biology. In 1982 the world has watched amazed as all phases of the surgical procedure, by which is a heart of dr. Barney Clark's replaced by artificial heart of aluminum and polyurethane, and named after the creator of “Jarvik 7”. The leader of the team from the University of Utah, et al. William Kolff, on this occasion said: "Very soon, a marathoner, with a super efficient artificial heart, will have to be disqualified because of the unfair advantage over other runners with normal hearts."

Artificial Hip

One of the most important artificial human parts at this time is artificial hip. In a complete replacement of this important part of the body, diseased and exhausted or injured hip is replaced with metal hip, along with the joint that is built into acrylic plastic cap. Acrylic cement fixates the artificial parts to the natural bone. Of course, there are problems: Artificial hip implanted in elderly is likely to last long enough, but the younger will have to undergo another surgical procedure when the cement is depleted. However, only five percent artificial hips should be changed after ten years of use, and expiration time depends on the type of artificial hip and cement structure.

Knee replacement surgery is also very common. As with hip, artificial knee is installed primarily to reduce the patient's pain, in most cases caused by arthritis.

Today, with the appropriate prosthesis, almost complete restoration of the normal function of the lost limb or part of the limb is possible. Very famous "Hand of Utah" - named after its author, dr. Steven Jacobson from the University of Utah, uses electrical impulses generated by muscle contraction. Electrodes on the remains of muscle arms send signals to microcomputer, located at the elbow of artificial hands and it instantly turns them into a command that runs hand in the desired direction.

Portable Kidneys

Dialysis - the removal of harmful substances from the blood machine that replaces the kidneys, is the only source of life for many patients. The patient is connected to the unit for dyalisis for a couple of hours a day, but that problem was solved by "portable kidney" - the battery powered device which is placed on the patient's chest, and which allows an easier life to these patients.

A prosthesis that replaces the trachea has enabled thousands of people to speak. Tiny electrodes embedded in the inner ear with associated battery bring back the hearing to deaf ears.

It is anticipated that the scientists will soon be able to fit in some micro cameras in the human eye, and within a micro-computer that will play the image to the brain to allow the blind to see.

Construction of insulin pump is significant because it automatically injects the pancreatic hormone in human body, thus avoiding the hypodermic needle.

Researchers are currently generating the pancreas to produce insulin and tissue cells are taken from the bodies of healthy animals.

Today most of the spare parts replace diseased, damaged or removed organs, but the scientists are increasingly working on creation of spare parts, which will not only act as the part of the body but will also stimulate growth of damaged organs.

One such example is the artificial skin, which is most widely used on burns. When placed on the burned skin area it provides the natural skin to grow and heal the wound which greatly reduces the risk of infection. In a similar way, they have made the blood vessels - the tissues and organs that carry out blood or any other liquid.

The Liver and The Lungs - No Copy

Although progress in the production of artificial parts is fantastic, some organs such as the lungs and liver, are too complex to be replaced at the present level of technology, but bionics is a young science and further major advances and achievements are expected.

Dr. Kolff from the University of Utah said: "People get luck and happiness, and not only the replacement of lost or diseased parts of the body."
It's nice to see a smile on the face of people who have fallen into grief and despair over the loss of a body part, because by their loss, they have also lost the part of themselves, and this science allows them to return to normal life, hope, inspiration and encouragement to go on.
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The Future of T-cell Vaccines

February 27, 2013, 10:35 am
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Generally, there are two types of immune response in humans. The first is natural immunity which includes neutrophils, macrophages, NK cells and complement defense system, and the second is acquired immune response which has two branches - cellular and humoral immunity.

Humoral immunity is consisted of B-cells and their products-antibodies, and today’s medicine offers vaccines that stimulate this type of immune response. Cellular immune response includes T-cells which are very important in human immunity, but, until now, no one succeeded to make a vaccine based on this type of immune response. News from this field are described in this article:

Biotechnical company “Genocea” hopes to produce first effective vaccine with T-cells. If true, this could redefine infectious medicine.
Traditional vaccines do not prevent some infectious diseases. Microbes that are hidden inside human cells and that cause chronic diseases are not blocked by the antibodies created as a response to standard vaccines.

Vaccines created by using T-cells, which trigger a different type of immune response, could in theory offer better prevention and control of chronic infection, but so far no one has been successful in the transfer of vaccine T-cells from the laboratory to the clinic.
Officials from biotech company Genocea from Cambridge, Massachusetts, state that high-throughput method, which uses the company, may change all that, says Technologyreview site. Its first clinical project to be tested is an experimental vaccine against herpes.

The Mechanisms of Action

All existing vaccines induce the body to produce antibodies that attach to the surface of microbes that cause infection and mark them for destruction. However, pathogens that live inside cells, such as viruses, some bacteria or other microbes that cause AIDS, malaria, herpes, tuberculosis and chlamydia, can avoid this defense mechanism.
For extracellular microorganisms, humoral immunity represented by B-cells and antibodies is very effective, but not against intracellular microbes. "In order to deal with this type of pathogen, we often had to stimulate what we call cell immunity. Unlike immune antibodies, which recognize pathogens directly, cellular immunity has to recognize your infected cell and to get rid of it," said Darren Higgins, a biologist at Harvard Medical School who is co-founder of Genocea and who studies the interactions between host and pathogen.

The activation of cellular immunity and the family of cells to fight infection as a part of T-cell immune response is a challenge. The method of trial and error, which is used to produce vaccine based on antibodies, does not work with the vaccine with T-cells.

Despite years of academic and industrial labor, and even clinical trials, there is currently no vaccine with T-cells in the market.
"We still do not know all the rules needed to product vaccines with T-cells, nor do we know how much it would be effective," said Robert Brunham, a physician-scientist at University of British Columbia in Vancouver, who is working to develop a T-cell vaccine against the chlamydia.

Indeed, our understanding of how T cells control the infection is still in the developing stage. The real challenge is how to identify the true protein, or antigen of the pathogen that will attract the attention of T-cells so they can signal that human cells contain infectious agents.
"If you can determine which parts the protein contains, then you can use that protein as a vaccine to train your immune system to react exactly as you need to external pathogens," said Higgins, who is now a consultant and scientific advisor in Genocea.

Magnitude of the challenge depends on the number of proteins that are decoded by the genome of pathogens. In thehe herpes simplex 2 each of about 80 proteins can be genome, and over one thousand proteins in Chlamydia and over 5,000 in malaria. Testing of each individual protein is a long and expensive process.

Genocea approach involves collecting as many pathogenic proteins as it reasonably could have been produced in the laboratory, and then observing how the human immune cells react to each of them.

Two Types of Cells Play Important role

Generally, this involves two types of isolation of immune cells in humans - T-cells and antigen-presenting cells, which carry the parts of bacteria or other pathogens on its outer surface and presenting them to T-cells. If T-cells produced immune-signaling molecules in response to a specific antigen, researchers in Genocea believe that specific antigen would be potential candidate for the vaccine.
But there is another level of complication related to the T-cell response, which requires a review of the group of candidates for the vaccine: human genetics.

Protein that triggers a response in one person, may not work for others, because there is a genetic diversity of structures that antigen-presenting cells use to treat antigens.

"In any case, it is a barrier that determines whether we get a universal vaccine or not and this is an area in which we are moving," said Brunhem.
Genocea hopes to approach these problems by testing how T cells respond to immune cells, depending on the genetic basis of diversity.

Genital Herpes Vaccine

Genocea plans to begin clinical trials for the vaccine against genital herpes. If it is successful, Genocea’s vaccines for herpes simplex 2 will be the first to fight against the disease that affects one of every six people aged between 15 and 49. Currently, patients can take antiviral drugs as a therapy, but there is no cure. Candidates for Genocea-vaccine would be the patients who already have the disease.

Genocea program for the vaccine against herpes is growing faster than traditional vaccine research which take sometimes 10 years to cross the path from discovery to the proven concept and as many as 20 years to reach the market, said Higgins.

This achievements are important first step in developing more advanced T-cell vaccines that can be used not only to prevent infectious diseases, but also some autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, Crohn's disease and AIDS.

However, sufficient clinical studies have not yet been conducted in order to confirm efficiency, safety and applicability of this new way of treatment.
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The Future of Long Lasting Flu Vaccine

March 1, 2013, 1:34 pm
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The flu season this year started too early in some parts of the northern hemisphere, and many people are literally scrambling to get their annual vaccine. This ritual, however, could become history.

The Properties of Influenza Virus

Influenza, or simply “flu” is a very common seasonal infectious disease of birds and mammals. It is caused by Influenza viruses that belong to Orthomyxoviridae family. All influenza viruses are divided to two groups, A and B. These are RNA viruses, which means that RNA is their genetic material. Common symptoms of the infection are: chills, fever, sore throat, muscle pains, headache (often severe), coughing, weakness/fatigue and general discomfort.

This illness is not dangerous for healthy people, although the severely diseased chronic patients may experience alteration of their symptoms and in that case, this infection might become even life threatening. There are three to five millions of severe cases of influenza reported per one year, and about 500000 deaths. According to the World Health Organization: "Every winter, tens of millions of people get the flu. Most are only ill and out of work for a week, yet the elderly are at a higher risk of death from the illness. We know the worldwide death toll exceeds a few hundred thousand people a year, but even in developed countries the numbers are uncertain, because medical authorities don't usually verify who actually died of influenza and who died of a flu-like illness."

Although there are many influenza vaccines today, they are not always effective due to abilities of this virus to quickly change its properties from season to season. It is a real challenge to produce highly effective, long lasting influenza vaccine, mostly because it is most commonly occurred pandemic disease.

New flu vaccine could be made of information RNA (mRNA), the genetic material that controls the production of proteins. Unlike its precursors, the new vaccine could last a lifetime and it would be possible to produce it quickly enough to stop the pandemic.

How Do We Get Immunity?

We become immune to the specific strain of flu when our system learns to recognize a key protein called HA and NA, which is located on the surface of the virus. This can happen either because we have caught the virus and found a way to win that particular type of influenza, or because we have received one of the standard vaccines, which contains a large amount of attenuated viral particles.

However, the flu is constantly evolving, so the viral proteins also change and our immunity to influenza doesn’t transfer from one to the next season. For each season, a new vaccine must be produced. Most influenza vaccines are grown in chicken eggs or cell cultures, a process that takes approximately six months to finish.

This delay means that the World Health Organization has to predict months before the virus appear, which type of the virus has the best chance to be one that will circle the world next winter. Pharmaceutical industry then creates a new vaccine based on WHO recommendations. Of course, these recommendations may be wrong, or worse - when a completely new virus causes a pandemic, its first wave can be completed before any vaccine is ready.

mRNA Vaccine Advantages

However, there may be a solution. mRNA, which controls the production of HA and NA of influenza virus, can be produced in great amounts in a few weeks, says Lothar Stitz from Friedrich-Lofler Institute in Germany. This mRNA can be stored in frozen dry powder which is not necessary to freeze, unlike most vaccines that must be kept refrigerated.

mRNA vaccine is producted by the immune cells, and then transferred to the protein. These proteins the body then recognizes as foreign, causing the immune response. The immune system will further identify proteins if it encounters a virus, allowing the fight against this type of flu.

Similar vaccines are made of DNA with the code for proteins of influenza. However, DNA vaccines may never be approved because of concerns that they could be incorporated into human DNA, thus disrupting gene regulation.

This risk, however, does not exist when it comes to the mRNA, because it can not become a part of the genome. For this reasons, "RNA probably has advantages over DNA when it comes to safety," said Jaze Bjarne Bogen from the University of Oslo in Norway, working on DNA vaccines.
Test RNA vaccines have failed, as they were quickly destroyed in the blood. But "Curevac" company from Tubingen in Germany, found a protein called protamine, which binds to RNA and protects it, which is applied in the mRNA vaccine against prostate cancer and lung cancer, which has already been tested on humans.

Preclinical Experiments

"Amazing, mRNA vaccine has never actually been tested against infectious diseases," said Stitch. His team used Curevac's process of creating durable mRNA vaccines for common types of human flu, and the H5N1 avian influenza. In tests in mice, ferrets, and pigs, the vaccine has very quickly increased antiviral antibody levels.

This has also triggered an immune response that does not involve antibodies, but active blood cells such as T cells, ie. cytotoxic T lymphocyte to destroy the pathogen. The vaccines which are made only of proteins do not cause this kind of reaction.

The fact that both types of responses were obtained simultaneously eliminates the infection more quickly, and may also protect from the flu for a long time, as long as the cells are recognizing the flu virus, and even after the viruses are evolved to avoid antibodies.

A universal flu vaccine, however, will stimulate the immunity against proteins that are common to all flu viruses, but that virus usually hides from the immune system. Stitch’s team made the mRNA vaccine of such type of protein of ordinary seasonal flu virus. The vaccine not only protects animals from this type of influenza, but also from the H5N1, the bird flu.

Vaccines that protect against all types of influenza could be possibly received during childhood, as well as vaccines against other diseases. Meanwhile, Stitch is also working on the mRNA vaccine against rabies. "We think that the mRNA could provide an excellent platform against viral, bacterial and fungal diseases," he said.
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Career Advice - MPH from Columbia or Boston University

March 1, 2013, 1:52 pm
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Hi everyone,

I have just been accepted to MPH programs in Epidemiology and Biostatistics at Columbia and Boston University. My end goal is to work in biopharma as a biostatistician/bioinformatics/clinical trials manager.

I have honestly been going back and forth with the two schools. Columbia has the obvious prestige factor, but BU is offering me a scholarship (not sure for how much yet). To those with industry experience: Would the pedigree of having gone to Columbia make a difference to a prospective employer or do they see past names?

Any insights would be wonderful.

Thanks a ton!
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PRIONS- An Infectious Life Without Genetic Material !

March 1, 2013, 10:36 pm
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A Prion in the Scrapie form is an infectious agent which is composed of protein in a misfolded form. This definition always remain a topic of debate as this is a hypothesis on prion and many different forms of such protein have been identified recently very similar to so called Prions.
Prions are contrast to all other known infectious agenst like Virus, Bacteria, Fungus as these agents contains nucleic acids which may be either DNA or RNA or both. The word prion derived from word protein and infection. Prions word is coined in 1982 by Stanley Prusiner. Many of the Prion’s infections are untreatable and are fatal in nature. They are responsible for Creutzfeldt-Jakob disease in humans, in other mammals they develop transmissible spongiform encephalopathies, in cattles they are responsible for development of bovine spongiform encephalopathy BSE which is also commonly known as “mad cow disease”. The diseases due to prions are affecting structures of brain and neural tissue.
The propagation of prions takes place by transmission of misfolded proteins state. When any prion enters a healthy organism, it converts existing properly folded proteins into the disease associated prion form by misfolding its protein state. This prion act as a template to further misfold proteins and convert them in to prion state. This triggers a chain reaction that produces large amount of the prion forms which is known as amvloid fold. This form of amvloid fold consists of tightly packed sheets which are known as beta sheets. Amyloid aggregates are fibrils, growing and replicates when two growing ends become four after breakage. The altered structure of protein which is prion are more stable and keeps on accumulating in infected tissue, thus damage tissue and cause cell death. This protein or prions are resistant to denaturation even with chemical and physical agents.

In 1997, Prusiner isolated the protein and was infectious agent mainly composed of protein. This isolated was a new breakthrough in prion research work, for this great contribution, Prusiner won the Nobel Prize in Physiology or Medicine.
The protein of prions is known as PrP. When they are found in healthy people, and in infectious state, they are material with different structure and are resistant to enzymes like proteases.

The replication of Prions is explained by two hypothetical models, the first one is known as Fibril model of prion propagation and the another one is known as Heterodimer model of prion propagation. The first model assume that the single PrPSC molecule binds to single PrPc molecule, this is further converted into PrPSc. The other model focuses on breakage of PrPc into PrPSC and further breakages into new seeds.
The formation of plaques also known as amyloid (aggregation of infectious protein) causes neurodegenerative disease by aggregating within the central nervous system. This disrupt normal tissue and are characterized by holes in the tissue. Such type of infections are characterized with absence of an inflammatory reaction. Once incubation period is over, the disease spreads rapidly and leads to damage of brain and death.
Such diseases are transmissible from one species to another. The Human Prion disease like Creutzfeldt-Jakob disease is believed to cause infections to cattle and is further transmitted through infected meat!

Sterilization of prions is very difficult as they are resistant to chemical agents, physical agents, and this is because their denaturation is difficult. Therefore the protein hydrolysis with caustic soda, bleach is generally done. There sterilization with steam is done by autoclaving them at 134 °C (274 °F) for 18 minutes. Another method of sterilization is to immerse in 1N NaoH and heat in a autoclave at 121 degree Celsius for 30 minutes. Or Immerse in 1N NaClO that is sodium hypochlorite for one hour.

Today the research on Prions is working to find out ways to cure such infections completely. The sophisticated use of modeling techniques and computer application in it is helping scientist to find out compounds to bind to cavity in the PrPc and stabilize the deformed proteins, decreasing the harmful effect of PrPs. Many work on antiprion antibodies capable of crossing the barrier of blood-brain and treating prions proteins has been successful and further studies will bring such products in market soon.

In 2011 , it was discovered to degrade prions by lichens. The way to diagnose prion disease including BSE and CJD is still practically difficult. The examination of brain using Immunohistochemical and Neurophathological method is only the way at present. The way ahead is developing techniques like amplification with novel method called surround optical fiber immunoassay and detecting amount of PrPsc in brain tissues.

Today, though the treatment for Prions is difficult but as always, it is possible for science to go at its roots and to develop a treatment which will completely cure infections of prions in simple ways !
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"Time bomb" Against Cardiovascular Disease

March 2, 2013, 4:35 am
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Arteriosclerosis, narrowing of the arteries that lead to the development of cardiovascular disease, is the leading cause of death in the world. Until now, there was no method of treatment of this disease that would lead to increased drug efficiency and reduce their harmful effects. To overcome this problem, a group of researchers from the Swiss "Unige", "HUG" and the University of Basel has developed an actual "time bomb", a method that can identify the affected area and treat them only.

In Switzerland, more than 20,000 people (37% of all deaths) die each year from cardiovascular disease caused by atherosclerosis. Different methods of treatment are available for patients, but there is no medicine that can treat only the affected area, which often causes a number of adverse effects. Intravenous injection of vasodilators (substance that dilates blood vessels), such as nitroglycerin, causes the dilatation of all blood vessels, not just those affected with the disease. This can cause a drop in blood pressure, which in turn leads to reduction of desired blood flow due to the vasodilatation of diseased blood vessels, which is unwanted, for example, in a heart attack. To increase the effectiveness of treatment in the fight against arteriosclerosis and to minimize side effects, the researchers from "UNIGE", "HUG" and the University of Basel has developed so-called nanocontainers which have the ability to release vasodilatators only in the diseased areas.

Nanotechnology in Medicine

Although no specific biomarkers for atherosclerosis have been identified, there is a physical phenomenon related to stenosis (narrowing of the blood vessels) known as the "shock of the blood vessel." This is due to fluctuations in blood flow caused by narrowing of the arteries. With the help of this phenomenon, the research team has developed a true "time bomb", a nanocontainer which, under pressure due to "shock of the blood vessel" in narrowed arteries, releases vasodilatating substances. By the rearrangement of the structure of individual molecules (phospholipids) in the ordinary nanocontainers such as liposome, scientists allowed them to change to the lenticular shape, opposite from the normal round shape.

The shape of the lens, nanocontainer can move smoothly through the healthy arteries. This new nanocontainer is perfectly stable, unless in case of shock of the constricted blood vessels. And that is exactly the intention of technological progress. Vasodilatators are distributed only in the narrowed arteries, significantly improving the effectiveness of treatment and reducing the side effects. "In short, we used the unexplored aspect of existing technology. This study provides a new perspective in the treatment of patients with cardiovascular disease, "explains Andreas Zumbuehl from the Department of Organic Chemistry," UNIGE ".

Nanomedicine is the discipline that comes from general nanoscience, only it is focused on medical research. Interdisciplinary cooperation between chemistry, physics, basic sciences and clinical medicine in the technological environment can lead to a new era in the study.

Contribution of Chemistry

How did scientists succeed to change shape of nanocontainers so they begun to look like the lens? By rearranging the structure of molecules, chemists in UNIGE replaced the links that connect the two parts of the phospholipids (head and tail) by amino group, an organic compound that promotes interaction among the phospholipids. After modifying, the molecules are hydrated, and then heated to form a liquid sphere which will relax in the lens shape by cooling. The researchers then created, for the purpose of the experiment, an artificial cardiovascular system using polymer pipes that are blocked at different levels to represent healthy and stenotic arteries. Then, the artificial extracardial pump is connected with the arteries to produce the shock of the narrowed blood vessels. Nanocontainer is inserted into the system, and samples were taken from diseased and narrowed parts. It was found that the drug was found in higher concentrations in diseased areas than in those that were healthy, and that its concentration is much higher than in the case of classical homogeneous distribution.

Nanomedicine in Creation of Artificial Blood Vessels

That would be a good solution for moderately damaged blood vessels. But what about the vessels that are highly damaged? They would need a replacement, and again, the nanomedicine has a possible solution.
An artificial artery created by British scientists will introduce a revolution in cardiac surgery. Blood vessel of polymers that prevent blood clots resembles spaghetti, because of its shape and flexibility. Therefore, it is more effective than synthetic arteries that are susceptible to clotting and too rigid to pulse in the rhythm of the heart.

Patients suffering from cardiovascular disease, heart attack or threatened with amputation because of blood clots in the arteries or the narrowing of blood vessels are forced to undergo the bypass surgery. As a bypass, or bypass the damaged part of the vessel, a piece of a healthy vein can be taken from the leg, or if the patient has no healthy veins (one in three), a plastic instrument, artificial arteries or veins - graft (graft ) are used. However, these plastic vessels that are currently in use are too rigid to pulse while the blood flows through the body and can not be found in small sizes, because they are not sufficiently effective. In addition, the material of which they are made stimulates the creation of blood clots.

Blood vessel which was developed late last year by professor George Hamilton, a vascular surgeon, and Alexander Sefalian, an expert in nanotechnology and tissue regeneration of the Royal Hospital in London, is made of a polymer that is enhanced with several types of special molecules. Some of them stimulate circulation, other stem cells that are "pinned" to the walls of the vessel. It enhances the flexibility and allows the use of small lumens (less than 8 mm).

The inner side of the "spaghetti" has a layer of millions of tiny prickles, each of which is a thousand times thinner than a human hair, that attract stem cells. Once they "enter" into the artery, stem cells grow and merge into the endothelium - a set of cells that cover the healthy blood vessels from inside. They overlay the entire interior of artificial arteries, which makes them flexible and prevents the formation of blood clots. New grafts pulsate rhythmically to fit a heartbeat. Material from which they are made is strong, flexible, resistant to clotting and can not be braked, most importantly. It was created with the help of nanotechnology, so that it can withstand a big pressure.
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The History Of "Discovery Of Penicillin" - Sir Alexander Fleming

March 2, 2013, 6:36 am
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Even though accidents are bound to happen, but at last, Science believes in truth and the same was proved by Scottish Scientist and Nobel laureate Alexander Fleming during his discovery of Penicillin !

The discovery of Penicillin “wonder drug” is surrounded with much myth as like Flemings Fluff, which was drifted in through a window near Paddington station, as like with Newton’s apple, with Archimedes interrupted bath, James Watts Kettle on the hob, to the great scientific legends.

Sir Alexander Fleming was a bacteriologist and was young at the time when he accidentally discovered one of the greatest modern medicines in 1929. It is believed that one day Alexander left a plate of staphylococcus bacteria and noticed that a mold fallen by mistake in the culture plate had killed lot of bacteria. This was visible clear area on the plate. He later confirmed and was surprised to discover that the mold had restricted the growth of bacteria. He identified the fungus as Penicillium notatum, very similar to the one found in bread. This was the breakthrough in his life and this discovery was one of the greatest of all time in the field of medicine. On 1929 on February 14, Fleming introduced his by-product from the same mold and called it as penicillin a wonder drug to cure many bacterial infections.

The story took a new turn when this drug was found to be broad spectrum in nature. This drug was called as wonder drug as was able to cure all types of bacterial infections at that time. Though the story is that Fleming had streaked a colony of staphylococci for his research and went on leave for few days and at the time when he returned, he had discovered a new mold which was able to kill staphylococci by producing penicillin, what so ever, but this had been a great discovery and helped to save millions and billions of life at that time.

Later it was again by luck that the research in to penicillin further began. It was early 1930s a group of scientist from Oxford University lead by Howard Floery and Chain Ernst began to work on the properties and purification methods of naturally occurring antibacterial substances. A Dollar 5000 grant from Rockefeller Foundation was given as the discovery of Flemings was initiated. The isolation of active ingredients and use of methods like freeze drying helped to obtain a million times more potential active ingredient than the Flemings crude material. In 1939 treatments was given to mice and latter in 1942 the product was successfully tested on Humans. Large scale production of penicillin began by 1944 for civilian use.

Penicillin antibiotics are significant as they are the first drug that were potential to kill many previously serious diseases, as syphilis, staphylococcus infections, streptococci infections. Penicillin is today also widely used even though many types of bacteria are resistant. All Penicillin drugs and its derivatives fall under Beta Lactum group of antibiotics and are used in against Gram-positive organisms and in many other treatments of bacterial infections.

The commonly used term for penicillin is penicillin G that is benzylpenicillin,benzathine benzyl penicillin and phenoxymethylpenicillin. It has been observed that in few patients, reactions to penicillin happens . This reactions are hypersensitivity, diarrhoea,nausea, urticaria, rash and superinfeciton.

The mechanism of action is at the stage of cell wall development, when a Bacteria attempt to divide, the presence of penicillin hampers it completely and the cell end up in shedding their cell walls. The Beta Lactam antibiotic inhibits the formation of peptidoglycan cros links of bacterial cell wall. This action takes place by binding of B-lactam ring of penicillin to the enzyme DD transpeptidase. This affects cell wall development and results in the death of cell. After treatment with Penicillin, the Gram positive bacteria are called as protoplast when they completely lose their cell wall. While the Gram negative bacteria are called as spheroplasts and they does not lose their cell wall.

With the development in this subject, Chemist, John Sheehan completely synthesized Penicillin in 1957 at the Massachusetts Institute of Technology for the first time. Sheehan spend 9 years (from 1948) in synthesizing penicillin chemically. Finally in 1957 he investigated the new methods for synthesis of peptides and related protecting groups. This synthesis was not completely suitable for Human use, but this new creations or new derivatives helps in developing new forms of penicillin with various other applications.

To discover anything great in science, it takes lot of hard work and dedication. Even though accidents are bound to happen, but at last, Science believes in truth and the same was proved by Scottish Scientist and Nobel laureate Alexander Fleming by discovering the "wonder drug" of modern medicine!
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Mice That Can Discover Landmines

March 3, 2013, 3:55 pm
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A land mine is an explosive device specifically created to be activated by applying certain pressure to its surface. The exact number of buried and unexploded landmines is unknown. However, it is estimated that millions of landmines and other unexploded ordnance are buried in more than 76 countries and territories in all regions of the world.

Landmines can keep its activity for more than 50 years after being buried into the ground. For this reason, all countries with large estimated number of land mines are making a great effort to discover them and to get rid of them. To do this, millions of landmines that are still buried in various of countries around the world must be located first. Finding these landmines is extremely difficult, as most minefields are unmarked. After marking the mines, there is still left to de-mine this areas, which is also difficult, dangerous and expensive.

Current Detection Technologies

Various detection technologies are currently used, each with limits or flaws. Dogs and other "sniffers" have high ongoing expenses, are subject to fatigue, and can be fooled by masked scents. Metal detectors are sensitive to metal mines and firing pins but cannot reliably find plastic mines. Infrared detectors effectively detect recently placed mines, but they are expensive and limited to certain temperature conditions. Thermal neutron activation detectors are accurate but are large for field use, slow, and expensive.

In early attempts, ground-penetrating radar was sensitive to large mines, had good coverage rate at a distance and with signal processing, could discriminate antitank mines from clutter such as rocks beneath the ground surface. This type of radar, however, remains expensive, cannot detect antipersonnel mines because its resolution is too low, and frequently records false alarms from clutter sources.

Therefore, there is a need to find new ways to find buried land mines, which would be faster, safer and more accurate than today’s.

The Implementation of Genetic Engineering

Researchers have created a mouse that is 500 times more sensitive to TNT then its normal relatives. This could be cheap and fast way of finding hidden explosives.

Scientists are creating super- mouse to search for landmines, thanks to its super-powerful sense of smell.

Researchers at Hunter College of the City University of New York, genetically modified these animals to be 500 times better equipped to sniff for mines then normal members of its kind. They hope that the "hero mice" will be able to warn people of the buried bombs.

Hidden landmines are deadly reality in nearly 70 countries worldwide, and their detection and removal is expensive and dangerous. At the present time, for their detection, the metal detectors, radars, magnetometers and sniffer dogs are used.

Belgian organization APOPO is already using African giant rats as a cheaper way of searching for landmines. Rats are not genetically modified, but their sense of smell is sharp enough to detect buried TNT. Seeking rats are trained to scratch the ground when they feel the hidden mine (fortunately, they are small enough not to trigger the explosives).
Although sniffers for mines are efficient (with two human guides they can search in one hour the area that would take two days for people with metal detectors), they still need nine months of training before they are reliable and the process costs about 6,000 euro per one rat.

On the other hand, genetically modified mice are due to incorporated molecules more sensitive to TNT, so they are expected to change its behavior involuntarily, which in turn means that they will not require long training.

Charlotte D’ Hulst, a molecular neurobiologist from Hunter College, who presented their work at the meeting of the Society of Neuroscientists, has used genetic modification to ensure that the mice have between 10,000 and one million neurons sensitive to the smell with receptors that detect TNT, compared to only 4,000 in the normal animal, which would "probably increase the sensitivity limits of this sense about 500 times," she said.

Each neuron of the smell sensor in the nose of the mouse is covered with a kind of smell receptors. Usually, one specific receptor comes on every thousand neurons sensitive to smell, but about half of the neurons sensitive to the smell of the D'Hust’s mice have a receptor for the detection of TNT.

The specific smell receptor was originally discovered by Danny Dhanasekaran, molecular biologist at the Medical College of the University of Oklahoma. Dhanasekaran says that the given smell is usually detected by a group of useful smell receptors, which help the natural noses more easily and accurately distinguish smells. However, artificial creation of an abundance of artificial receptors that can detect TNT, D'Hulst and her colleagues may increase the sensitivity of the system, so that “it would become easy to use them in the operations of mine discovery," says Dhanasekeran, who continued to search for other types of TNT receptors.

D'Hulst hopes that this huge commitment to one smell will provide a simple way to know whether or not modified mice encountered TNT. Recent research suggests that the sudden and intense stimulation of the olfactory system in mice induce a seizure. "We can only hope that our mice will get a seizure when they detect landmine. We do not have to work with the food reward and we will probably use a system of radio signals. The chip implant can monitor report and record their behavior. "

The Barriers for Implementation

Researchers have not yet tested the behavior of mice in the study. Roger Hess, director of field operations in the Golden West Humanitarian Foundation, a charitable organization that develops technology to help remove landmines, considers this method of sniffing for mines to be an improvement, but it will still depend on the detection of released steam from the mine. “The release of smell from the soil may depend on soil conditions and weather conditions, a trace of explosives may be located a few feet away from the place where the mine is actually buried”, he said. The technique also will not work for mines which do not have an opening through which the smell of explosives can go out.
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Scientists Created Genetically Engineered Mosquitoes That Cannot Transmit Malaria

March 3, 2013, 5:53 pm
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One of the most common and most effective ways to combat the spread of malaria epidemics is the control of mosquitoes that transmit this disease from one human to another. Unfortunately, it turned out that this type of fighting against epidemic can not be fully controlled. Mosquito disinsection in the past few years has been less effective because the mosquitoes quickly developed immunity to pesticides that have been used to destroy them. A similar process occurs with the parasite that causes malaria, which repeatedly continues to developed resistance to various drugs that come from science labs.

But it is possible that science finally has a solution that does not mean the destruction of large populations of mosquitoes carrying malaria, according to ArsTechnica. In fact, several years ago began testing in the wilderness during which the mosquitoes that transmit Dengue fever were infected with a special kind of bacteria that prevents the spread of the virus. In a recently published study, a team of scientists published almost sensational results of long-term experiments – they were able to create genetically modified mosquitoes that, even if you pick up the malaria virus, are not capable of transmitting it to humans. Very simply put: scientists forced the mosquitoes to eject specific antibodies that destroy parasites every time they feed on human blood.

Current Solutions

Various antibodies and vaccines in the past have proved to be quite inefficient methods of treatment and prevention of the spread of epidemic malaria. Vaccines have been largely ineffective because the Plasmodium falciparum (a parasite that causes malaria) demonstrated a remarkable ability to develop resistance to almost every vaccine that scientists are tried to develop to destroy it. This parasite is rapidly evolving and developing immunity to the vaccine often completely changing the proteins that are found on the surface, and all thatin order to "confuse" the antibodies. The method by which the parasite camouflages is possible, however, only after the Plasmodium falciparum has got the body of the host.

Plasmodium and Immune System

Mosquitoes, on the other hand, have no immune system based on the antibody as it is the case in humans, which means that the parasite does not have to resort to all sorts of tricks while in the bodies of mosquitoes. For this reason, scientists have managed to create a special type of antibody that recognizes the structure of protein of parasite that cause human malaria, specific for the life stage of the parasite at the time when its host is a mosquito.

Antibodies that attack the malaria parasite are usually a complex combination of four proteins (two heavy and two light chains). To avoid the rather tedious process of inserting all the genes for entire combination of four proteins that build antibodies, scientists have developed a compact version of the antibody, which contains only one gene in which the parts of heavy and light chains are combined. At this point, scientists inserted two compact genes that encourage development of antibodies in a special place in the mosquito genome. To limit the impact of the antibodies on the mosquitoes, the researchers ensured that the antibody genes "activated" only after a mosquito ate his first meal, or come into contact with the victim's bloodstream.

No Risk for Mosquitoes

As for the risk of this genetic modification of mosquitoes harming themselves, scientists claim that tests have found that the fear is unwarranted. On the female mosquitoes, genes with antibodies had absolutely no effect, and the males were only minimally reduced in life expectancy. It is important to note that this shortened life span in no way affects the reduction of mosquito populations since the genetically modified mosquitoes can easily experience a period of sexual maturity. So, concerning mosquitoes, the new genes did nothing bad practically, which were definitely good news for scientists who seem to have managed to find a solution to combat malaria that fits to all involved parties (of course, to all but to the parasite that causes the disease).

If it is to believe the results of this study, scientists have finally succeeded. To use a metaphor, from mosquitoes that transmitted malaria they were able to create a hotel in which the virus can check in, but has no way to check out. Once Plasmodium falciparum enters the body of the mosquito, he must find a way to get the salivary glands in order to spread to other organisms. Specific genes inserted into the genome of mosquito managed to prevent this migration, so they practically stopped to be an important link in the chain of spread of malaria epidemics.

But not all research results were in line with the wishes of scientists. In one of four genetically modified mosquito populations, effects of new anti-malarial genes were not as clearly visible as in the remaining populations. It is evident, therefore, that scientists expect more hard work to find a solution for the final suppression of malaria epidemic. In the next few years, scientists will devote particular attention to new experiments and potential side effects of genetic engineering, and only then, if all goes according to the plan, the areas with frequent epidemics of malaria can expect significant progress on this issue.

The Future of New Strategy

Only after successful upcoming testing, scientists could take action in genetic modification of all known populations of mosquitoes that transmit malaria pathogens. They will do this by releasing into the wild quite numerous swarms of genetically modified mosquitoes which will then mix with the "normal" mosquitoes and thus, according to the laws of evolution, the two genes that have been created in laboratories would be transmitted to the offspring. It will take several generations of mosquitoes to complete this process.

If the new genes do not bring some significant advantages to mosquitoes (and probably will not), they will probably disappear from their genomes in a few generations. This of course means it will be necessary to release new amounts of genetically modified mosquitoes at regular intervals. Even if that is the case, this method will still continue to be much more efficient than the currently existing long-term control solutions. Also, the periodic release into the wild of genetically modified mosquitoes will suppress the growing danger for mosquitoes to develop resistance to pesticides that are currently used. In that case, people would lose their B-plan to stop the spread of epidemics of malaria, which can be extremely dangerous.
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Help, please. Let's help more children.

March 3, 2013, 9:33 pm
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Dear Sir or Madam,

Have you heard about anything that a technology that using child's salvia or blood to have genetic test to figure out an child's potential?

Currently, I am looking for a US bio-tech company that has such technology or conducting this similar research. Our company is currently looking for import this technolog in our early education services. If you know something about this or any appropriate companies, please let me know.

I will truly appreciate your help.


Thanks so much, and thanks for your time.
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