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    924151 3-monoclonal-polyclonal-peptide-biological-research-products-knock-out-ratAt the annual conference of the American Academy of Neurology (AAN), which will be held from April 26 to May 3 in Philadelphia, will be presented to the successful outcome of Phase II clinical trial of two brand new compared to existing drugs for the prevention of migraine attacks, according to a press release AAN. Both drugs are used first for the prevention of migraine monoclonal antibody. The creators promise a new era of medicine in preventive therapy for this disease.

    Target against which drugs work, also not previously been involved in order to prevent migraine attacks - monoclonal antibodies block the calcitonin gene-related peptide (CGRP), synthesized by cells of the central and peripheral nervous system neurotransmitter that plays a key role in the transmission of pain.

    During the first tests of medicines, ALD403, 163 patients suffering from migraine attacks from five to 14 days per month or one placebo dose. Over the next six months, the group received the drug was observed 66 percent reduction in the number of attacks per month, compared to 52 percent reduction in the group receiving placebo. In 16 percent of the participants received the drug group attacks were completely absent for three months, which was not observed in the placebo group. Difference in side effects between the groups was observed.

    In trials of another drug, LY2951742, 217 patients suffering from migraine from 4 to 14 days a month, for three months received twice weekly subcutaneous injections of placebo or drug. In the group receiving therapy, there was a 63 percent reduction in seizure frequency per month compared with a 42 percent decline in the placebo group. In patients receiving the drug were noted side effects such as pain at the injection site, pain in the abdomen and upper respiratory tract infection, but in general medicine was found to be safe and well tolerated.

    Although both drugs is still the third phase of clinical trials, according to the representative of the University of California (San Francisco) Godsbi Peter (Peter Goadsby), participated in the creation and testing of both drugs, the results are potentially promising new era in preventive treatment of migraine.

    Migraine affects about 14 percent of the adult population and, according to the global health research people on Earth Global Burden of Disease Survey in 2010, is the seventh of disabling diseases.

    antibioticsIn a boom for manufacturers of medicinal products has become a new enzyme acting as a specialized "wrench" in the structure of antibiotics.
     
    In the so-called kiromisin scientists discern right tool for the creation of these drugs at the molecular level so that we treated more precisely.

    Scientists from the University of North Carolina hope to modify this enzyme successfully synthesize stronger and more adaptable antibiotics based on natural compounds, which at the same time sparing the body more than the ones we use now.
     
    As is known, they are quite harmful because it effectively destroyed the natural body mechanism which protects us from all disease - the immune system. And she could not fully recover by itself.

    When you take antibiotics not only kill the "bad" but the good microbes, leaving the intestines almost completely exhausted the useful regulating the immune response to intestinal flora and therefore seriously compromised immune system as a whole.

    The kiromisin can be created by natural and synthetic drugs to withdraw from the chemical laboratory. It is only factory producing the assembly shown by enzymes each of which performs its own specific function.
     
    This process would give the medical ability to "stand" on nature in the creation of various drugs that will be cheaper, more efficient and at the same time protecting human health and the environment.

    Tuesday, 15 April 2014 09:52

    Gene editing cures rare liver disease

    CRISPR is very easy to configure and customize equipmentUsing a new system of genetic editing based on bacterial proteins by researchers from MIT cured rare liver disease caused by a single genetic mutation.

    The findings described in the edition of Nature Biotechnology, provide the first evidence that the technique of editing of a gene known as CRISPR, can reverse disease symptoms.

    CRISPR, which offers an easy way to crop the mutated DNA and replacement with the correct sequence has the potential to treat many genetic diseases, according to the research team.

    Recently developed CRISPR system relies on cellular mechanism that bacteria use to protect themselves from viral infection.

    Researchers have copied this cell system for the creation of gene-editing complexes, including DNA.

    They are cut enzyme called Cas9, bound to the RNA strand, which can be programmed to bind to a specific genomic sequence.

    Meanwhile, researchers deliver DNA template strand.

    When repairing cell damage resulting from Cas9, scientists introduced the template DNA in the genome.

    Scientists predict that this type of revision of the genome one day could help in the treatment of diseases such as hemophilia, Huntington's disease, and the like, caused by a single mutation.

    There are other systems developed on the basis of genetic editing of DNA enzymes known as nucleases, but these complexes can be expensive and difficult to assemble.

    In contrast, CRISPR is very easy to configure and customize equipment.

    Thursday, 10 April 2014 10:33

    Tobacco plants are struggling with virus

    Tobacco plants are struggling with virusInternational research group led by Professor Chen has developed a new generation of potentially safer and more cost-effective therapies against West Nile virus etc, and other pathogens.

    Scientists applied therapy based on monoclonal antibodies and their derivatives.

    For the purposes of the study monoclonal antibodies are derived from tobacco plants, which is promising to change the image of the plant, which are believed to cause cancer of the lung.

    The antibodies are directed against proteins located on the surface of the virus.

    The main objective of the study is to create innovative, sustainable and affordable therapy that also be a cheap solution to combat the global threat of West Nile virus.

    One approach is the development of therapeutic antibodies that bind to receptors which may help of the monoclonal antibodies to cross into the brain.

    In a new study, the researchers developed a half-dozen new options that could assist in the implementation monoclonal antibodies that can be effectively targeted to the brain and to neutralize the dangerous virus.

    The final results of the study show 90% success in preventing letalnit development in experimental conditions.

    This is the first case of such an effect, leading to the neutralization of the virus.

    Dr. Chen results are motivating the development of plant-based therapy that dramatically reduce the cost of commercial production of monoclonal antibodies.

    The virus is spread by infected mosquitoes and affect the central nervous system.

    Infection can cause serious, life-altering and even fatal disease.

    Until now, however, is not available or effective drug therapy for dealing with infection.

    Wickerhamomyces arborarius falsecolourResearchers from the National Collection of Yeast Cultures (NCYC) at the Institute of Food Research (IFR) have identified a new globe-trotting yeast species that lives on tree-associated beetles. This new species demonstrates the importance of preserving biodiversity, as yeasts like this may help efforts to develop renewable fuel sources in the future.

    Preserving biodiversity must go beyond plants and animals and also preserve the microbial life. Threats to habitats, for example through oil exploration, could destroy forever potential solutions to global challenges locked up in the microbial life itself. Yeasts, well known for their role in brewing beer and baking bread, can also ferment sugars from plant material into biofuels. However, this process isn’t very efficient, especially when waste plant matter is used, as the structures are tough to break down.

    Different yeasts use different types of sugars, thrive in different conditions and produce a diverse range of different products. Crossing strains with just the right mix of characteristics could produce a yeast that’s perfect for biofuel production. The announcement of the production of the first artificial yeast chromosome demonstrates how using synthetic biology gives us an opportunity to design a new yeast with these characteristics. But identifying these relies on studying and preserving yeast biodiversity.

    In an effort to address this issue, NCYC, which is based at IFR on the Norwich Research Park, has recently initiated a programme to screen its 4000+ different yeast strains to find the biofuel-producing stars. But it wants more.

    “We’re looking for interesting yeasts from interesting habitats,” said Dr Steve James.

    The search for yeast biodiversity spans the globe, and has just yielded an entirely new species. Wickerhamomyces arborarius was first discovered on a flower growing in the high altitude Maquipucuna cloud forest in north-west Ecuador. It’s the latest in a long standing collaboration between NCYC and the Colección de Levaduras Quito Católica (CLQCA) in Ecuador. The Ecuadorian team, led by Dr Javier Carvajal, has been scouring unique and sensitive habitats such as the cloud forests, the Amazon rainforest, the Andean highlands as well as the Galápagos Islands in search of novel yeasts, which NCYC then characterises and preserves.


    Xyleborus glabratus-dorsallateral
    With funding from the Biotechnology and Biological Sciences Research Council (BBSRC), NCYC have been characterising this yeast. Genomic analysis of the Ecuadorean yeast revealed it had no known matches. But over time, other yeast hunters found similar strains of the Ecuadorean species. One was found on a nutgall tree in a remote mountainous region of Taiwan by Dr Ching-Fu Lee of the National Hsinchu University of Education. Three other strains were identified from wood-boring beetles living on laurel trees in Georgia, USA, by Dr Thomas Harrington from Iowa State University, whose research team were investigating how these beetles transmit a fungal pathogen known to cause laurel wilt disease.

    “This new species is a real globetrotter,” said Dr James. “It’s possible the yeast originated in Asia, and was subsequently brought to the USA by these insects. Although this beetle has yet to be found in Ecuador, three other very similar species have recently been found there, so it’s possible that the yeast got to South America via the beetles too.”

    Interestingly, one of the US strains was isolated from a beetle that had been surface sterilised, potentially indicating that this yeast species actually lives inside the insect, in its gut. This isn’t unusual, as like us, insects host gut flora – bacteria and yeasts that help them digest their food. These particular beetles eat wood, and rely on their microbial gut flora to help digest its tough structure. The same structure is found in the sorts of waste plant materials that could be suitable sources of biofuels if only more efficient ways of realising their potential were available. If this yeast is indeed a gut symbiont of the beetles, it should also be resistant to some of the breakdown products from wood digestion that can inhibit other biofuel-producing yeasts.

    The NCYC team are now fully characterising this new species, and plan to test what characteristics might be useful for the production of biotechnological applications.

    “We’re really interested in finding out how this yeast evolved tolerance to rotting wood environments, to guide attempts to improve production yeasts,” said Dr Ian Roberts, curator of the NCYC. “It’s just the sort of characteristic you’d put into a designer yeast for biofuel production.”

    In testing and characterising yeast, he and his team work closely with Professor Keith Waldron and his colleagues in The Biorefinery Centre at the Institute of Food Research, which is strategically funded by the Biotechnology and Biological Sciences Research Council.

    But their search for more yeasts to add to their collection continues. Conservative estimates put the current total number of yeast species at 150,000, and so far globally we’ve possibly discovered only 1% of this total. NCYC’s Ecuadorean collaboration has yielded dozens of new, as yet uncharacterised yeasts, and more extreme environments and habitats are currently being explored for the chance to find potentially useful yeasts. But unless we preserve those habitats, and the precious biodiversity they contain, we could lose that chance forever.

    20121005125618-elisa-kits-assayGeneticists were able to produce yeast artificial chromosome. This is great progress in the emerging field of synthetic biology, which is to make reality the creation of new drugs, new nutrients or biofuels.

    Until now, scientists were able to create only the chromosomes of bacteria and viral DNA, which have a much simpler architecture. This road, which took seven years of effort by an international team of scientists, led to the construction of a genome and assembly of 273 871 base pairs of DNA from yeast. The total number is slightly lower than its natural equivalent, which has exactly 316 667.

    In fact, the team of scientists has been made ​​numerous changes to the genetic basis of this chromosome, removing unnecessary portions, which are not necessary for the reproduction and growth of the chromosome.

    "Our study carry synthetic biology from theory to reality," said Jeff militant, director of the Institute for Genetic systems in the medical center Langon NYU. He led the study, published online Thursday in the American journal Science.

    According to him, "this work is the biggest step of the international effort to build a complete genotype of synthetic yeast."

    This chromosome eukaryotes (contains genes in the cell nucleus of all plants and animals) which has undergone unprecedented changes are then incorporated into the living cells of the beer yeast.

    The latter reacted quite normal, but gained new qualities that do not exist in the natural yeast, stress researchers. They note that these yeasts have 16 chromosomes total, while the man is 23, wrote Monday.

    "Changing the genome is like making bets because inappropriate modification can kill the cell," said Professor more militant. "We had over 50,000 changes in the DNA of the chromosome and our yeast is still alive, which is remarkable," he boasted.

    This technique of re-assembly of the chromosome, scientists will be able to manipulate the genome of yeast and to impart certain qualities. Thus, from now on, it should be possible to develop artificial yeast species, which can produce a rare drug or some vaccines, of which one is that of hepatitis B, which is derived from yeast.

    The artificial yeast may also be used to stimulate the development of more efficient biofuel.

    peptides-elisa-targatt-culture-pcr-knockin-mouse-targatt-knockinA new study published in the Proceedings of the National Academy of Sciences USA, PNAS, conducted by researchers at the Ruhr University in Bochum, shows how peptides can be designed so that attack bacterial cells.

    Researchers believe that the disposal of pathogenic bacteria could be done without harming human cells.

    Moreover, this type of therapy would reduce the risk of resistance that developed most pathogens to previously applied drugs.

    Previous studies have already shown that many antimicrobial peptides interact with cell membranes of the bacteria and thus perform its microbicidal effect.

    RUB team has turned his attention to the study of a peptide called MP196, which is a group of very small positively charged peptides consisting of four to ten amino acids.

    From previous studies it is known that the MP196 can cope with a variety of bacteria including some that are multi - drug-resistant, but it is unclear exactly how this process is carried out.

    Researchers have demonstrated that prevents MP196 proteins in the cell membrane of the bacteria and thereby distort two key cellular processes: cell wall biosynthesis and cell breathing.

    Through disruption of cell wall biosynthesis, the peptide interferes with the integrity of the bacterial cell, and by interfering with the cellular respiration, distorts the production of ATP, the molecule that stores the energy used by the cell.

    Scientists are confident that the MP196 offers a starting point for developing new drugs that attack specific classes of bacteria without harming human cells, but to be confirmed in their findings need to go a long way.

    The study is part of the development of innovative antibiotics.

    To solve new drugs, federal authorities need detailed information about the procedure and the effects of drugs on both pathogens and on human cells.

    New blood vessel formation (angiogenesis) stimulates the growth of cancer and other diseases. Anti-angiogenic inhibitors slow down cancer growth by disrupting the blood supply to the tumor. To date, the success of these treatments is limited by resistance, poor efficiency and harmful side effects. In the journal Cell, Peter Carmeliet (VIB-KU Leuven) and his team reported that sugar metabolism (a process that we call glycolysis) also plays an essential role in the formation of new blood vessels. These totally revolutionary insights open up many new therapeutic opportunities for the treatment of cancer and diseases as a result of excessive blood vessel formation.

    Every growing cell in our body is provided with oxygen and nutrients via our blood vessels. Blood vessels are formed by endothelial cells which line the inside wall of the vessel. These cells require energy to be able to form new blood vessels. However, it was not known how these cells produced the required energy and it was never considered to inhibit the energy production process in order to block angiogenesis.
    Under the guidance of Peter Carmeliet, a team consisting of Katrien De Bock, Maria Georgiadou and Sandra Schoors discovered that glycolysis is the most important mechanism for endothelial cells to supply energy for blood vessel formation. Peter Carmeliet and his team demonstrated that endothelial cells can be paralyzed by blocking glycolysis and consequently stop to form blood vessels. This is the first evidence that starvation of endothelial cells could offer new therapeutic opportunities for the treatment of excessive angiogenesis in diseases (like cancer).
    Peter Carmeliet: "Our discovery opens up a whole new domain for inhibition of angiogenesis in various diseases such as cancer. Endothelial cells need nutrients and energy for growth and if you take away their energy, you can prevent them from forming new blood vessels."

    mice with glioblastomaSwedish researchers have discovered a new method to combat cancer. In scientific journals it a completely new mechanism to fight cancer through the explosion of cancer cells.

    Experts on the science of cancer of the Karolinska Institute in Stockholm said that they were able to cause tumor growth in mice. Through the introduction of the drug they induce growth of a specific type of brain tumor called glioblastoma. Subsequently, after taking another drug they say they were able to prevent tumor development and growth of cancer cells.

    The substance, which is carried out the experiments is called 1 - Vakvinol, which may be administered in tablet form. It has been found that molecules of the particular drug may be incorporated in the cancer cells. In this way they cause the development of a process called vacuolation. In this order the cells swell by extracting fluid from the interstitial space and their incorporation in a vacuole inside the cell, which gradually increases in size. Subsequently, the cancer cell starts to break down, the walls thin and gradually this led to its literal explosion and death.

    Research and their research have been conducted on mice with glioblastoma, which scientists say is true and applicable to other types of cancer cells. This medicament is believed to have the same mechanism of action in humans, but in a different half-life, i.e. the dose in mice and will be different in different time intervals, while in humans will seek saturation and higher plasma concentration for maximum effect.

    The study is the result of many years of research into new methods of drug treatment of cancer, during which scientists have crashed millions of cancer cells particles to determine which of the tested drugs effect will be the strongest. Vakvinol-1 is defined as the definitive drug and scientists say the drug substance to be registered as soon as possible and move in phase 1 clinical trials compared to patients who are suffering from malignant forms of cancer.

    Claims of scientists are complemented by the fact that the experimental conditions in mice implanted tumor cells of human glioblastoma, which subsequently started his own development. Mice were fed with crushed tablets Vakvinol -1 in five consecutive days of drug experimentation. The results show that all six of the eight mice survived after drug administration, while in the control group of the infected mice with human glioblastoma, mortality is recorded as 100% , that is, 30 of each 30 mice were infected reached fatal. Surviving mice with specific therapy lived 80 more days, according to the researchers is equivalent to decades of human life, even allowing for full treatment.

    Professor Patrick Ernfors tissue from the Department of Biology at the Karolinska Institute, Stockholm, said he was proud of the scientific discovery of the research team, because this is an entirely new mechanism to fight cancer, which will be introduced in clinical trials. According to him, possible drug will combat cancer cells in an entirely new pathophysiological mechanism that would protect people from the harmful effects and side effects of other forms of drug therapy of cancers that currently exist.

    layered nanostructure held together by DNA

    Nanoparticles linked by complementary DNA strands form a bcc superlattice when added layer-by-layer to a DNA coated substrate. When the substrate DNA is all one type, the superlattice forms at a different orientation (top row) than if the substrate has both DNA linkers (bottom row). GISAXS scattering patterns (right) and scanning electron micrographs (inset) reveal the superlattice structure.

    Dreaming up nanostructures that have desirable optical, electronic, or magnetic properties is one thing. Figuring out how to make them is another. A new strategy uses the binding properties of complementary strands of DNA to attach nanoparticles to each other and builds up a layered thin-film nanostructure through a series of controlled steps. Investigation at the U.S. Department of Energy Office of Science's Advanced Photon Source has revealed the precise form that the structures adopted, and points to ways of exercising still greater control over the final arrangement.

    The idea of using DNA to hold nanoparticles was devised more than 15 years ago by Chad Mirkin and his research team at Northwestern University. They attached short lengths of single-stranded DNA with a given sequence to some nanoparticles, and then attached DNA with the complementary sequence to others. When the particles were allowed to mix, the "sticky ends" of the DNA hooked up with each other, allowing for reversible aggregation and disaggregation depending on the hybridization properties of the DNA linkers.

    Recently, this DNA "smart glue" has been utilized to assemble nanoparticles into ordered arrangements resembling atomic crystal lattices, but on a larger scale. To date, nanoparticle superlattices have been synthesized in well over 100 crystal forms, including some that have never been observed in nature.

    However, these superlattices are typically polycrystalline, and the size, number, and orientation of the crystals within them is generally unpredictable. To be useful as metamaterials, photonic crystals, and the like, single superlattices with consistent size and fixed orientation are needed.

    Northwestern researchers and a colleague at Argonne National Laboratory have devised a variation on the DNA-linking procedure that allows a greater degree of control.
    The basic elements of the superlattice were gold nanoparticles, each 10 nanometers across. These particles were made in two distinct varieties, one adorned with approximately 60 DNA strands of a certain sequence, while the other carried the complementary sequence.

    The researchers built up thin-film superlattices on a silicon substrate that was also coated with DNA strands. In one set of experiments, the substrate DNA was all of one sequence – call it the "B" sequence – and it was first dipped into a suspension of nanoparticles with the complementary "A" sequence.

    When the A and B ends connected, the nanoparticles formed a single layer on the substrate. Then the process was repeated with a suspension of the B-type nanoparticles, to form a second layer. The whole cycle was repeated, as many as four more times, to create a multilayer nanoparticle superlattice in the form of a thin film.

    Grazing incidence small-angle x-ray scattering (GISAXS) studies carried out at the X-ray Science Division 12-ID-B beamline at the Argonne Advanced Photon Source revealed the symmetry and orientation of the superlattices as they formed. Even after just three half-cycles, the team found that the nanoparticles had arranged themselves into a well-defined, body-centered cubic (bcc) structure, which was maintained as more layers were added.

    In a second series of experiments, the researchers seeded the substrate with a mix of both the A and B types of DNA strand. Successive exposure to the two nanoparticle types produced the same bcc superlattice, but with a different vertical orientation. That is, in the first case, the substrate lay on a plane through the lattice containing only one type of nanoparticle, while in the second case, the plane contained an alternating pattern of both types (see the figure).

    To get orderly superlattice growth, the researchers had to conduct the process at the right temperature. Too cold, and the nanoparticles would stick to the substrate in an irregular fashion, and remain stuck. Too hot, and the DNA linkages would not hold together.
    But in a temperature range of a couple of degrees on either side of about 40° C (just below the temperature at which the DNA sticky ends detach from each other), the nanoparticles were able to continuously link and unlink from each other. Over a period of about an hour per half-cycle, they settled into the bcc superlattice, the most thermodynamically stable arrangement.

    GISAXS also revealed that although the substrate forced superlattices into specific vertical alignments, it allowed the nanoparticle crystals to form in any horizontal orientation. The researchers are now exploring the possibility that by patterning the substrate in a suitable way, they can control the orientation of the crystals in both dimensions, increasing the practical value of the technique.