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GENTAUR Europe

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    Displaying items by tag: Gentaur

    A nurse in a hospital that held France's only confirmed case of the SARS-like coronavirus that has killed 18 people has been admitted to hospital in northern France on suspicion on being infected herself, French health officials said on Friday.

    Gentaur-antibodies-monoclonal-peptide-Hopital-Douai

    The World Health Organisation (WHO) raised the number of cases confirmed worldwide to 33 after Saudi Arabia said that two people who were admitted to hospital there in April had been determined by laboratory analysis to be infected.

    There is no evidence so far of sustained human-to-human transmission of the coronavirus. But health experts are concerned about clusters of new possible cases of nCoV, which started in the Gulf and spread to France, Britain and Germany.

    Two people who had contact with the confirmed French case, a 65-year-old man who fell ill on returning from Dubai, were admitted to hospital late on Thursday.

    One was a patient who shared a ward with him when he was in a hospital in the town of Valenciennes, northern France, at the end of April, and the other is a doctor who treated him there.

    The 65-year-old, who is in stable but serious condition, was transferred to an isolated intensive care wing in Douai near Lille, which is where the third case appeared. He was transferred to Lille on Thursday night.

    "We identified it overnight. It corresponds to the investigations we've been undertaking since our confirmed case of the coronavirus," said Sandrine Kueny, deputy director of the regional health agency.

    The nurse worked in the hospital's infectious disease unit but it was unclear whether she had direct contact with the sick man.

    The coronavirus is from the same viral family that triggered the outbreak of Severe Acute Respiratory Syndrome (SARS) that swept the world after starting in Asia in late 2003 and killed 775 people.

    Giving details of the two new Saudi cases, Saudi deputy health minister Ziad Memish said in an email to the web-based disease monitoring system ProMED that a study of earlier reported cases and repeat testing of suspected cases had identified two additional cases on May 8.

    The first patient was a 48-year-old man with multiple coexisting medical conditions who became ill on April 29. He was in stable condition, the WHO said.

    The second patient was a 58-year-old man with an existing medical condition who became ill on April 6. He fully recovered and was discharged from hospital on May 3.

    Memish added in the email that actions taken by Saudi authorities since May 1 had prevented new cases emerging.

    Since the beginning of May, 15 patients have been reported from the Saudi outbreak, of which seven had died, the WHO said. Of the 15 patients, 12 were men and three women. The age range of the patients are from 24 to 94 years old.

    French authorities advise that anyone who has recently traveled to the Gulf region consult a doctor in case of fever.

     

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    Published in News

    Heart failure is one of the most debilitating conditions linked to old age, and there are no specific therapies for the most common form of this condition in the elderly. A study published by Cell Press May 9th in the journal Cell reveals that a blood hormone known as growth differentiation factor 11 (GDF11) declines with age, and old mice injected with this hormone experience a reversal in signs of cardiac aging. The findings shed light on the underlying causes of age-related heart failure and may offer a much-needed strategy for treating this condition in humans.

    "There has been evidence that circulating bloodstream factors exist in mammals that can rejuvenate tissues, but they haven't been identified. This study found the first factor like this," says senior study author Richard Lee of the Harvard Stem Cell Institute and Brigham and Women's Hospital.

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs, causing shortness of breath and fatigue, and it is becoming increasingly prevalent in the elderly. The most common form of age-related heart failure involves thickening of heart muscle tissue. But until now, the molecular causes and potential treatment strategies for this condition have been elusive.

    To identify molecules in the blood responsible for age-related heart failure, a team led by Lee and Amy Wagers of the Harvard Stem Cell Institute and Joslin Diabetes Center used a well-established experimental technique: they surgically joined pairs of young and old mice so that their blood circulatory systems merged into one. After being exposed to the blood of young mice, old mice experienced a reversal in the thickening of heart muscle tissue. The researchers then screened the blood for molecules that change with age, discovering that levels of the hormone GDF11 were lower in old mice compared with young mice.

    Moreover, old mice treated with GDF11 injections experienced a reversal in signs of cardiac aging. Heart muscle cells became smaller, and the thickness of the heart muscle wall resembled that of young mice. "If some age-related diseases are due to loss of a circulating hormone, then it's possible that restoring levels of that hormone could be beneficial," Wagers says. "We're hoping that some day, age-related human heart failure might be treated this way."

    Published in News

    mosquito gentaur antibodiesScientists funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, have established an inheritable bacterial infection in malaria-transmitting Anopheles mosquitoes that renders them immune to malaria parasites. Specifically, the scientists infected the mosquitoes with Wolbachia, a bacterium common among insects that previously has been shown to prevent malaria-inducing Plasmodium parasites from developing in Anopheles mosquitoes. Before now, researchers had been unable to create mosquitoes with a stable Wolbachia infection that passed consistently from mother to offspring.

    In this study, led by Zhiyong Xi, Ph.D., at Michigan State University, the researchers focused on Anopheles stephensi mosquitoes, the primary malaria carrier in the Middle East and South Asia. The scientists injectedWolbachia into male and female embryos of A. stephensi and, once they matured, mated the adult females with uninfected male mosquitoes. A stable Wolbachia infection was maintained for 34 generations of mosquitoes, at which time the study ended. The researchers also introduced Wolbachia infection into uninfected adult mosquitoes in a series of experiments in which infected female mosquitoes comprised 5 percent, 10 percent or 20 percent of the mosquito population. In all three experiments, 100 percent of the mosquitoes were infected within eight generations, supporting the potential of Wolbachia-infected mosquitoes as a malaria control strategy. Similar approaches have been used successfully to control dengue, another mosquito-borne disease, in certain settings.

    In their examination of how Wolbachia affects Plasmodiumparasites, the researchers found that the bacterium kills the parasites both in the mosquito midgut, where the parasites mature, and in the salivary glands, from which the parasites are transmitted to humans via mosquito bites. The scientists hypothesize that Wolbachia infection causes the formation of unstable compounds known as reactive oxygen species (ROS), which inhibit the development of the parasites. Future studies might examine whether Plasmodium can become resistant to ROS and explore ways to integrate Wolbachia-infected mosquitoes with existing malaria control strategies, the researchers write.

    Read more about Survival of Wolbachia pipientis in Cell-Free Medium

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    PRODUCT DESCRIPTION: Each frozen aliquot contains 1 mL of a pure, titered culture of Enterococcus faecium. The identification of this organism was confirmed by 16S sequencing. The purity of the culture was monitored by Gram staining and by additional culturing. The titer was performed on one aliquot after freezing. The freezing medium contains 15% glycerol as a cryoprotectant. Please see the Certificate of Analysis for the specific freezing medium used.

    INTENDED USE: Live, titered microorganisms can be used to determine a limit of detection (LOD), in diagnostic assay development or crossreactivity studies. When used as a control for nucleic acid tests, the same protocols as those used to amplify clinical specimens should be employed.

    BIOSAFETY: Enterococcus faecium is a biosafety level 2 microorganism and must be used within Biological Safety Level 2 facility or cabinet. Please consult your institution’s regulations regarding the use of this organism.

    PRECAUTIONS:
    - Use Universal Precautions, this organism is potentially biohazardous.
    - Repetitive freezing and thawing is not recommended (aliquot material if necessary). Titer will be altered by a single freeze-thaw.
    - To avoid cross-contamination, use separate pipette tips for all reagents.

    RECOMMENDED STORAGE:
    Titered material should be stored at -65°C or below.

    DO NOT USE IN HUMANS:
    These products are intended for research, product development, or quality assurance. These products are NOT intended for use in the manufacture or processing of injectable products subject to licensure under section 351 of the Public Health Service Act or for any other product intended for administration to humans.

    Catalog #: 0801892

    Contact us for additional information

    Published in Promos

    PRODUCT DESCRIPTION: Each frozen aliquot contains 1 mL of a pure, titered culture of Corynebacterium diphtheriae. The identification of this organism was confirmed by 16S sequencing. The purity of the culture was monitored by Gram staining and by additional culturing. The titer was performed on one aliquot after freezing. The freezing medium contains 15% glycerol as a cryoprotectant. Please see the Certificate of Analysis for the specific freezing medium used.

    INTENDED USE: Live, titered microorganisms can be used to determine a limit of detection (LOD), in diagnostic assay development or crossreactivity studies. When used as a control for nucleic acid tests, the same protocols as those used to amplify clinical specimens should be employed.

    BIOSAFETY: Corynebacterium diphtheriae is a biosafety level 2 microorganism and must be used within Biological Safety Level 2 facility or cabinet. Please consult your institution’s regulations regarding the use of this organism.

    PRECAUTIONS:
    - Use Universal Precautions, this organism is potentially biohazardous.
    - Repetitive freezing and thawing is not recommended (aliquot material if necessary). Titer will be altered by a single freeze-thaw.
    - To avoid cross-contamination, use separate pipette tips for all reagents.

    RECOMMENDED STORAGE:
    Titered material should be stored at -65°C or below.

    DO NOT USE IN HUMANS:
    These products are intended for research, product development, or quality assurance. These products are NOT intended for use in the manufacture or processing of injectable products subject to licensure under section 351 of the Public Health Service Act or for any other product intended for administration to humans.

    Catalog #: 0801882

    Contact us for additional information 

    Published in Promos

    PRODUCT DESCRIPTION: Each frozen aliquot contains 1 mL of a pure, titered culture of Staphylococcus simulans. The identification of this organism was confirmed by 16S sequencing. The purity of the culture was monitored by Gram staining and by additional culturing. The titer was performed on one aliquot after freezing. The freezing medium contains 15% glycerol as a cryoprotectant. Please see the Certificate of Analysis for the specific freezing medium used.

    INTENDED USE: Live, titered microorganisms can be used to determine a limit of detection (LOD), in diagnostic assay development or crossreactivity studies. When used as a control for nucleic acid tests, the same protocols as those used to amplify clinical specimens should be employed.

    BIOSAFETY: Staphylococcus simulans is a biosafety level 2 microorganism and must be used within Biological Safety Level 2 facility or cabinet. Please consult your institution’s regulations regarding the use of this organism. 

    PRECAUTIONS:
    - Use Universal Precautions, this organism is potentially biohazardous.
    - Repetitive freezing and thawing is not recommended (aliquot material if necessary). Titer will be altered by a single freeze-thaw.
    - To avoid cross-contamination, use separate pipette tips for all reagents.

    RECOMMENDED STORAGE:
    Titered material should be stored at -65°C or below.

    DO NOT USE IN HUMANS:
    These products are intended for research, product development, or quality assurance. These products are NOT intended for use in the manufacture or processing of injectable products subject to licensure under section 351 of the Public Health Service Act or for any other product intended for administration to humans.

    Catalog #: 0801728

    Contact us for additional information 

    Published in Promos

    vaccine-gentaur-bullet-blender-gold-kronos-dio-targattThe dream of many scientists to create a vaccine against AIDS has failed. National Institutes of Health in the U.S. announced that it attempts to immunize volunteers with an experimental vaccine known as HVTN 505 is officially terminated, since it is clear that it does not prevent infection.

    Clinical trial began in 2009 and since then, 1,250 voluntary participants received vaccine and 1244 others - control infusion of placebo, both groups over a period of 24 weeks. Among all the volunteers in total, so far has 41 infected with HIV than those who received the vaccine and 30 infected than those who received placebo. The study focused mainly people who have unprotected sex.

    Vaccine strategy using "double whammy" that aimed to strengthen the immune system. Three initial injections are placed initially, and after 16 weeks - another injection containing genetic material which creates a molecule of the type produced by HIV in order to induce a response in the immune system against viruses. Scientists say the vaccine itself did not cause infection. After presenting the matter collected data and results collected until mid-April at the National Institute of Allergy and Infectious Diseases, which sponsored the clinical trial recommended stopping the attempt to create the vaccine. Volunteers will be monitored for 5 years, and the data will be analyzed for further information.

    Published in News

    PRODUCT DESCRIPTION: Each frozen aliquot contains 1 mL of a pure, titered culture of Staphylococcus lugdunensis. The identification of this organism was confirmed by 16S sequencing. The purity of the culture was monitored by Gram staining and by additional culturing. The titer was performed on one aliquot after freezing. The freezing medium contains 15% glycerol as a cryoprotectant. Please see the Certificate of Analysis for the specific freezing medium used.

    INTENDED USE: Live, titered microorganisms can be used to determine a limit of detection (LOD), in diagnostic assay development or crossreactivity studies. When used as a control for nucleic acid tests, the same protocols as those used to amplify clinical specimens should be employed.

    BIOSAFETY: Staphylococcus lugdunensis is a biosafety level 2 microorganism and must be used within Biological Safety Level 2 facility or cabinet. Please consult your institution’s regulations regarding the use of this organism. 

    PRECAUTIONS:
    - Use Universal Precautions, this organism is potentially biohazardous.
    - Repetitive freezing and thawing is not recommended (aliquot material if necessary). Titer will be altered by a single freeze-thaw.
    - To avoid cross-contamination, use separate pipette tips for all reagents.

    RECOMMENDED STORAGE:
    Titered material should be stored at -65°C or below.

    DO NOT USE IN HUMANS:
    These products are intended for research, product development, or quality assurance. These products are NOT intended for use in the manufacture or processing of injectable products subject to licensure under section 351 of the Public Health Service Act or for any other product intended for administration to humans.

    Catalog #: 0801555

    Contact us for additional information

    Published in Promos
    Monday, 29 April 2013 10:11

    Candida albicans Z006, DNA (1 μg)

    PRODUCT DESCRIPTION: Each aliquot contains 1 μg of DNA extracted from a pure culture of Candida albicans. The identification of this organism was confirmed by rDNA sequencing. The purity of the culture was monitored by additional culturing and Gram staining to detect any contaminating bacteria. The DNA was extracted from the cells following a protocol based on the yeast protocol provided in the Qiagen® Genomic DNA Handbook and using Qiagen® Genomic DNA Buffers with a 500/G genomic tip. DNA concentration and OD260/280 ratios are determined using a NanoDrop ND- 1000®. The extracted DNA also tested positive on an in-house real time PCR assay.

    INTENDED USE: Purified Genomic DNA is designed for use as an amplification and/or detection control for nucleic acid testing of Candida albicans. It can also be used to determine a limit of detection (LOD), in diagnostic assay development, cross-reactivity studies or genomic sequencing. When used as a control for nucleic acid tests, the same protocols as those used to amplify extracted clinical specimens should be employed.

    PRECAUTIONS:
    - Use Universal Precautions when handling Genomic DNA.
    - The material may be re-frozen after thawing. Repetitive freezing and thawing is not recommended (aliquot material if necessary).
    - To avoid cross-contamination, use separate pipette tips for all reagents.

    RECOMMENDED STORAGE:
    This control is supplied in TE Buffer and should be frozen at -20°C or below.

    DO NOT USE IN HUMANS:
    These products are intended for research, product development, quality assurance or manufacturing use. These products are NOT intended for use in the manufacture or processing of injectable products subject to licensure under section 351 of the Public Health Service Act or for any other product intended for administration to humans.

    Catalog #: 0801504DNA-1μg

    Contact us for additional information

     

    Published in Promos

    130422154756-largeCurrent techniques for turning patients' marrow cells into cells of some other desired type are relatively cumbersome, risky and effectively confined to the lab dish. The new finding points to the possibility of simpler and safer techniques. Cell therapies derived from patients' own cells are widely expected to be useful in treating spinal cord injuries, strokes and other conditions throughout the body, with little or no risk of immune rejection.
    "These results highlight the potential of antibodies as versatile manipulators of cellular functions," said Richard A. Lerner, the Lita Annenberg Hazen Professor of Immunochemistry and institute professor in the Department of Cell and Molecular Biology at TSRI, and principal investigator for the new study. "This is a far cry from the way antibodies used to be thought of -- as molecules that were selected simply for binding and not function."
    The researchers discovered the method, reported in the online Early Edition of the Proceedings of the National Academy of Sciences the week of April 22, 2013, while looking for lab-grown antibodies that can activate a growth-stimulating receptor on marrow cells. One antibody turned out to activate the receptor in a way that induces marrow stem cells -- which normally develop into white blood cells -- to become neural progenitor cells, a type of almost-mature brain cell.
    Nature's Toolkit
    Natural antibodies are large, Y-shaped proteins produced by immune cells. Collectively, they are diverse enough to recognize about 100 billion distinct shapes on viruses, bacteria and other targets. Since the 1980s, molecular biologists have known how to produce antibodies in cell cultures in the laboratory. That has allowed them to start using this vast, target-gripping toolkit to make scientific probes, as well as diagnostics and therapies for cancer, arthritis, transplant rejection, viral infections and other diseases.
    In the late 1980s, Lerner and his TSRI colleagues helped invent the first techniques for generating large "libraries" of distinct antibodies and swiftly determining which of these could bind to a desired target. The anti-inflammatory antibody Humira®, now one of the world's top-selling drugs, was discovered with the benefit of this technology.
    Last year, in a study spearheaded by TSRI Research Associate Hongkai Zhang, Lerner's laboratory devised a new antibody-discovery technique -- in which antibodies are produced in mammalian cells along with receptors or other target molecules of interest. The technique enables researchers to determine rapidly not just which antibodies in a library bind to a given receptor, for example, but also which ones activate the receptor and thereby alter cell function.
    Lab Dish in a Cell
    For the new study, Lerner laboratory Research Associate Jia Xie and colleagues modified the new technique so that antibody proteins produced in a given cell are physically anchored to the cell's outer membrane, near its target receptors. "Confining an antibody's activity to the cell in which it is produced effectively allows us to use larger antibody libraries and to screen these antibodies more quickly for a specific activity," said Xie. With the improved technique, scientists can sift through a library of tens of millions of antibodies in a few days.
    In an early test, Xie used the new method to screen for antibodies that could activate the GCSF receptor, a growth-factor receptor found on bone marrow cells and other cell types. GCSF-mimicking drugs were among the first biotech bestsellers because of their ability to stimulate white blood cell growth -- which counteracts the marrow-suppressing side effect of cancer chemotherapy.
    The team soon isolated one antibody type or "clone" that could activate the GCSF receptor and stimulate growth in test cells. The researchers then tested an unanchored, soluble version of this antibody on cultures of bone marrow stem cells from human volunteers. Whereas the GCSF protein, as expected, stimulated such stem cells to proliferate and start maturing towards adult white blood cells, the GCSF-mimicking antibody had a markedly different effect.
    "The cells proliferated, but also started becoming long and thin and attaching to the bottom of the dish," remembered Xie.
    To Lerner, the cells were reminiscent of neural progenitor cells -- which further tests for neural cell markers confirmed they were.
    A New Direction
    Changing cells of marrow lineage into cells of neural lineage -- a direct identity switch termed "transdifferentiation" -- just by activating a single receptor is a noteworthy achievement. Scientists do have methods for turning marrow stem cells into other adult cell types, but these methods typically require a radical and risky deprogramming of marrow cells to an embryonic-like stem-cell state, followed by a complex series of molecular nudges toward a given adult cell rate. Relatively few laboratories have reported direct transdifferentiation techniques.
    "As far as I know, no one has ever achieved transdifferentiation by using a single protein -- a protein that potentially could be used as a therapeutic," said Lerner.
    Current cell-therapy methods typically assume that a patient's cells will be harvested, then reprogrammed and multiplied in a lab dish before being re-introduced into the patient. In principle, according to Lerner, an antibody such as the one they have discovered could be injected directly into the bloodstream of a sick patient. From the bloodstream it would find its way to the marrow, and, for example, convert some marrow stem cells into neural progenitor cells. "Those neural progenitors would infiltrate the brain, find areas of damage and help repair them," he said.
    While the researchers still aren't sure why the new antibody has such an odd effect on the GCSF receptor, they suspect it binds the receptor for longer than the natural GCSF protein can achieve, and this lengthier interaction alters the receptor's signaling pattern. Drug-development researchers are increasingly recognizing that subtle differences in the way a cell-surface receptor is bound and activated can result in very different biological effects. That adds complexity to their task, but in principle expands the scope of what they can achieve. "If you can use the same receptor in different ways, then the potential of the genome is bigger," said Lerner.
    In addition to Lerner and Xie, contributors to the study, "Autocrine Signaling Based Selection of Combinatorial Antibodies That Transdifferentiate Human Stem Cells," were Hongkai Zhang of the Lerner Laboratory, and Kyungmoo Yea of The Scripps Korea Antibody Institute, Chuncheon-si, Korea.
    Funding for the study was provided by The Scripps Korea Antibody Institute and Hongye Innovative Antibody Technologies (HIAT).

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