Saturday, August 15, 2009
News From The American Chemical Society, May 27, 2009
Amid concerns about a pandemic of swine flu, researchers from Nebraska report for the first time that poultry carcasses infected with another threat - the "bird flu" virus - can remain infectious in municipal landfills for almost 2 years. Their report is scheduled for the June 15 issue of ACS' semi-monthly journal Environmental Science & Technology. Shannon L. Bartelt-Hunt and colleagues note that avian influenza, specifically the H5N1 strain, is an ongoing public health concern. Hundreds of millions of chickens and ducks infected with the virus have died or been culled from flocks worldwide in efforts to control the disease. More than 4 million poultry died or were culled in a 2002 outbreak in Virginia, and the carcasses were disposed of in municipal landfills. Until now, few studies have directly assessed the safety of landfill disposal. "The objectives of this study were to assess the survival of avian influenza in landfill leachate and the influence of environmental factors," says the report. The data showed that the virus survived in landfill leachate - liquid that drains or "leaches" from a landfill - for at least 30 days and up to 600 days. The two factors that most reduced influenza survival times were elevated temperature and acidic or alkaline pH. "Data obtained from this study indicate that landfilling is an appropriate method for disposal of carcasses infected with avian influenza," says the study, noting that landfills are designed to hold material for much longer periods of time. ARTICLE: "Survival of the Avian Influenza Virus (H6N2) After Land Disposal" http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/es900370x CONTACT:Shannon L. Bartelt-Hunt, Ph.D.University of Nebraska-LincolnOmaha, Neb. Silver nanoparticles show "immense potential" in prevention of blood clots Scientists are reporting discovery of a potential new alternative to aspirin, ReoPro, and other anti-platelet agents used widely to prevent blood clots in coronary artery disease, heart attack and stroke. Their study, scheduled for the June 23 issue of ACS Nano, a monthly journal, involves particles of silver - 1/50,000th the diameter of a human hair - that are injected into the bloodstream. Debabrata Dash and colleagues point out that patients urgently need new anti-thrombotic agents because traditionally prescribed medications too-often cause dangerous bleeding. At the same time, aging of the population, sedentary lifestyle and spiraling rates of certain diseases have increased the use of these drugs. Researchers are seeking treatments that more gently orchestrate activity of platelets, disk-shaped particles in the blood that form clots. The scientists describe development and lab testing of silver nanoparticles that seem to keep platelets in an inactive state. Low levels of the nanosilver, injected into mice, reduced the ability of platelets to clump together by as much as 40 percent with no apparent harmful side effects. The nanoparticles "hold immense potential to be promoted as an antiplatelet agent," the researchers note. "Nanosilver appears to possess dual significant properties critically helpful to the health of mankind - antibacterial and antiplatelet - which together can have unique utilities, for example in coronary stents." ARTICLE: "Characterization of Antiplatelet Properties of Silver Nanoparticles" http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/nn900277t CONTACT:Debabrata Dash, M.D., Ph.D., D.Sc.Professor and HeadDepartment of BiochemistryInstitute of Medical SciencesBanaras Hindu UniversityVaranasi, India "Gene silencing" may improve treatment of a deadly complication of liver disease A technique that "silences," or turns off, genes shows promise as a potential new treatment for liver fibrosis - the disease that leads to cirrhosis - scientists in Tennessee are reporting. Their study is scheduled for the June 1 issue of ACS' Molecular Pharmaceutics, a bi-monthly journal. Cirrhosis is the 12th leading cause of death in the United States. Ram Mahato and colleagues note that fibrosis involves build-up of scar tissue in the liver from chronic liver damage caused by hepatitis, alcohol abuse, toxins, or other factors. Advanced fibrosis can lead to cirrhosis, a condition in which the liver becomes so severely damaged that patients may require a transplant. There is no effective treatment, and patients urgently need new medications. Scientists believe one may emerge from the fascinating discovery that a protein called TGF-beta 1 triggers liver inflammation and that blocking the protein may help. The researchers designed 10 chemically synthesized substances, termed siRNAs, with the ability to block or "silence" the TGF-beta 1 gene in the liver. When put into rat liver cells, the "gene silencers" decreased levels of type 1 collagen whose excessive production leads to fibrosis, as well as two other substances known to trigger liver inflammation, by almost 50 percent. The results suggest that gene silencing may be "an efficient and more specific approach for therapy of liver fibrosis," the report states. ARTICLE: "TGF-#1 Gene Silencing for Treating Liver Fibrosis" http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/mp9000469 CONTACT:Ram I. Mahato, Ph.D.University of Tennessee Health Sciences CenterDepartment of Pharmaceutical SciencesCancer Research BuildingMemphis, Tenn. 38103 New "microcapsules" put more medication into the bloodstream to treat disease Scientists are reporting a potential solution to a problem that limits the human body's ability to absorb and use medications for heart disease, Type-2 diabetes, cancer and other conditions. It is a "nano-hybrid microcapsule" that enables the stomach to absorb more of these so-called "poorly-soluble" medicines. Their study is scheduled for the June 1 issue of ACS' Molecular Pharmaceutics, a bi-monthly journal. Finding ways to improve the stomach's uptake of poorly soluble medicines has been one of the major challenges facing pharmaceutical companies. Estimates suggest, for instance, that 40 percent of potential new drugs fall into this category. In the new study, Clive Prestidge and colleagues note that one solution has been to include detergent-like substances in pills and capsules. However, that approach involves safety concerns, since the detergent can irritate the stomach lining, making it unsuitable for drugs that must be taken month after month. The scientists describe development of a first-of-its-kind microcapsule made from lipid oils and nanoparticles 1/50,000th the width of a human hair. Although acting like conventional detergents, they seem unlikely to irritate the stomach. In test tube experiments, microcapsule versions of the arthritis drug, indomethacin, dissolved up to five times faster than a regular version of the drug. Lab rats given the new microcapsule version absorbed almost twice as much of the drug. ARTICLE: "Dry Hybrid Lipid-Silica Microcapsules Engineered from Submicron Lipid Droplets and Nanoparticles as a Novel Delivery System for Poorly Soluble Drugs" http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/mp900063t CONTACT:Clive Prestidge, Ph.D.Sector Coordinator for Bio and Polymer InterfacesIan Wark Research InstituteUniversity of South AustraliaMawson Lakes, South Australia Reducing salt in food without losing that salty taste Food manufacturers are searching for new ways to reduce the amount of salt added to products ranging from potato chips to salad dressings while preserving the salty taste that consumers crave, according to an article scheduled for the June 1 issue of Chemical & Engineering News, ACS' weekly newsmagazine. C&EN assistant editor Carmen Drahl notes in the article that researchers have been working toward that goal for years, as consumers concerned about high blood pressure sought to limit salt intake on the advice of public health officials. But finding a replacement for salt, or sodium chloride, is no simple task. One of the problems researchers face is lack of a detailed understanding of the basic biology of salty taste. But new pieces of the puzzle are emerging, including the discovery last year of what some scientists claim is the primary receptor responsible for human salt taste perception. Despite this challenge, companies are forging ahead with salt reduction research. One of the most widely used salt replacers, potassium chloride, resembles salt in terms of cooking performance but has a bitter taste that some consumers find unpleasant. Several companies are developing additives to mask this bitterness. Other approaches include developing smaller salt particles so that the tongue perceives their taste more quickly. Other researchers are exploring oil-based salt emulsions that provide an enhanced perception of saltiness while using less salt. No one strategy seems to work for every food and beverage, the article notes, but help is on the way. ARTICLE: "Seeking Saltiness" http://pubs.acs.org/cen/science/87/8722sci1.html Source: Michael Woods American Chemical Society
Indirect Transmission Can Trigger Influenza Outbreaks In Birds
New data on the persistence of avian influenza viruses in the environment has allowed a team of University of Georgia researchers to create the first model that takes into account both direct and indirect transmission of the viruses among birds. The model, which is detailed in the early online edition of the journal Proceedings of the National Academy of Sciences, has the potential to shed new light on how outbreaks begin in wild bird populations. "The environmental transmission of avian influenza among birds is quite rare, but our model shows that it can play an important role in outbreaks," said lead author Pejman Rohani, professor in the UGA Odum School of Ecology. "There are situations where ignoring the possibility of environmental transmission would cause you to significantly underestimate the probability, magnitude and duration of an outbreak." Rohani explained that current models of avian influenza only take into account the direct transmission of the virus that occurs when infected waterfowl and shorebirds shed the virus in their feces and those nearby drink contaminated water. But research in the UGA College of Veterinary Medicine has revealed that some avian influenza viruses can persist in water for up to 150 days. So even when no infected birds are present, Rohani said, virus present in the water can trigger an outbreak. Models that only take into account direct transmission, he pointed out, would incorrectly conclude that there's no risk of an outbreak when no infected birds are present. The viruses the researchers studied are known as low-pathogenicity viruses and do not infect humans. Low-path viruses only cause mild symptoms in birds but have the potential to swap genes and give rise to high pathogenicity viruses that can cause massive die-offs in poultry and - in rare cases - can infect humans. The H5N1 avian influenza virus, for example, has a 60 percent mortality rate in humans and is responsible for 262 deaths worldwide since 2003, according to the World Health Organization. "We need to understand low-path viruses because they are a storehouse of genetic variation that can give rise to new and potentially dangerous strains," said study co-author John Drake, assistant professor of ecology. In addition to the environmental persistence of the virus, the team's model takes into account variables such as lake size and the rate at which infected birds recover to describe likely and worse case outbreak scenarios. The model also reveals that environmental transmission extends the duration of an outbreak by infecting birds that haven't come into contact with other birds yet have consumed contaminated water. The data on the environmental persistence of avian influenza viruses comes from the lab of David Stallknecht, associate professor in the department of population health in the UGA College of Veterinary Medicine. In a study recently published in the journal Veterinary Microbiology, Stallknecht and lead author Justin Brown determined the persistence of 12 low-path avian influenza viruses under natural ranges of pH, salinity and temperature. The researchers found that the duration of persistence varied widely among viruses, but that the viruses generally are most stable at a slightly basic pH, temperatures of less than 63 degrees Fahrenheit (17 degrees Celsius) and in fresh to slightly brackish water. "The role of the environment in the transmission of avian influenza has been almost completely undefined, and that's what makes this research so exciting," said Brown, a post-doctoral researcher. "Migration and other factors relating to the biology of the avian host are still very important factors that drive the epidemiology of avian influenza, but now we can look at various environments and ask if they're better or worse for the transmission of avian influenza." Source: Sam Fahmy University of Georgia
Animal Production And Health To Be Addressed At FAO/IAEA Symposium
An international symposium to be held in Vienna next week will focus on the use of nuclear technologies to enhance animal nutrition and reproduction strategies and to detect and control animal-origin diseases that can be transmitted to humans, such as swine and avian influenza. Around 500 animal production and health experts from over 100 countries will present up-to-date findings for solving or alleviating factors affecting animal production. In addition, they will discuss modern techniques for curbing animal diseases that affect humans, also known as "zoonoses", which account for 70 percent of all human infectious diseases. The four-day FAO/IAEA Symposium on Sustainable Improvement of Animal Production and Health, is organized by the Joint Division of the Food and Agricultural Organization (FAO) of the UN and the IAEA. David Nabarro, UN System Coordinator on Avian and Human Influenza and the Global Food Security Crisis, will deliver a keynote address at the symposium's opening session at 9:00 a.m., on 8 June in the Vienna International Center's C Building. There will be a press conference featuring:
Werner Burkart, IAEA Deputy Director General and head of the agency's Department of Nuclear Sciences and Applications;
Modibo Traore, FAO Assistant Director-General, Agriculture and Consumer Protection Department; and
Gottfried Brem, Chair of Animal Breeding Genetics, Veterinary University Vienna, Austria, and Member of the European Research Council (ERC) in Brussels. More information and the programme of the Symposium is available at http://www-pub.iaea.org/MTCD/Meetings/Announcements.asp?ConfID=35424 BACKGROUND: The Joint FAO/IAEA Animal Production and Health effort enhances global food security by implementing sustainable livestock production systems using nuclear and nuclear-related techniques. The program assists Member States with the efficient use of local feed resources, adequate livestock management and breeding programs, and tools to control and prevent animal and zoonotic diseases. The Vienna symposium aims to provide a clear overview of the current and future use of nuclear and nuclear-related techniques in solving livestock problems, alleviating rural poverty, controlling the spread of diseases and enhancing food security and food quality. Topics on the agenda will include interactions among nutrition, reproduction and genotype, effects of environment on animal productivity, detection and control of trans-boundary, emerging and zoonotic diseases and achieving food safety and security in the 21 century. Nuclear technologies are used in many areas of livestock research and production. For example, isotopic tracer techniques can measure the nutritive value of feedstuff, to determine the nutrient intake or energy balance of animals, and to study the metabolism of nutrients in the animal body. The research helps to formulate balanced diets to achieve efficient growth and production. Isotopic methods are also used to monitor reproductive status, leading to better breeding management. Nuclear techniques are also used in livestock disease diagnosis. For example, isotopic technologies offer great advantages in measuring reactions very precisely and accurately. Scientists use them to produce better diagnostic tools and tests or to follow the progress of a drug through the body. Better diagnostics will help provide early diagnoses of diseased animals, while better drugs or vaccines will help reduce the losses due to the disease agent. The Joint FAO/IAEA Division assists Member Countries of the two organizations to use nuclear techniques and related biotechnologies for improving strategies for sustainable food security. Its co-ordinates and supports research worldwide; supplies technical and advisory services for projects and training activities; provides laboratory support and training through the FAO/IAEA Agriculture and Biotechnology Laboratory at Seibersdorf, Austria; and collects, analyses and disseminates information for effective transfer of skills and technology. Source: IAEA Press Office International Atomic Energy Agency
Werner Burkart, IAEA Deputy Director General and head of the agency's Department of Nuclear Sciences and Applications;
Modibo Traore, FAO Assistant Director-General, Agriculture and Consumer Protection Department; and
Gottfried Brem, Chair of Animal Breeding Genetics, Veterinary University Vienna, Austria, and Member of the European Research Council (ERC) in Brussels. More information and the programme of the Symposium is available at http://www-pub.iaea.org/MTCD/Meetings/Announcements.asp?ConfID=35424 BACKGROUND: The Joint FAO/IAEA Animal Production and Health effort enhances global food security by implementing sustainable livestock production systems using nuclear and nuclear-related techniques. The program assists Member States with the efficient use of local feed resources, adequate livestock management and breeding programs, and tools to control and prevent animal and zoonotic diseases. The Vienna symposium aims to provide a clear overview of the current and future use of nuclear and nuclear-related techniques in solving livestock problems, alleviating rural poverty, controlling the spread of diseases and enhancing food security and food quality. Topics on the agenda will include interactions among nutrition, reproduction and genotype, effects of environment on animal productivity, detection and control of trans-boundary, emerging and zoonotic diseases and achieving food safety and security in the 21 century. Nuclear technologies are used in many areas of livestock research and production. For example, isotopic tracer techniques can measure the nutritive value of feedstuff, to determine the nutrient intake or energy balance of animals, and to study the metabolism of nutrients in the animal body. The research helps to formulate balanced diets to achieve efficient growth and production. Isotopic methods are also used to monitor reproductive status, leading to better breeding management. Nuclear techniques are also used in livestock disease diagnosis. For example, isotopic technologies offer great advantages in measuring reactions very precisely and accurately. Scientists use them to produce better diagnostic tools and tests or to follow the progress of a drug through the body. Better diagnostics will help provide early diagnoses of diseased animals, while better drugs or vaccines will help reduce the losses due to the disease agent. The Joint FAO/IAEA Division assists Member Countries of the two organizations to use nuclear techniques and related biotechnologies for improving strategies for sustainable food security. Its co-ordinates and supports research worldwide; supplies technical and advisory services for projects and training activities; provides laboratory support and training through the FAO/IAEA Agriculture and Biotechnology Laboratory at Seibersdorf, Austria; and collects, analyses and disseminates information for effective transfer of skills and technology. Source: IAEA Press Office International Atomic Energy Agency
A Closer Look At The I-Con™ - Isolation And Containment For Pandemic Control
American Innovative Research (A.I.R.) cofounders, David Palmer and Judy Piscione, explain how the impact of the avian flu pandemic originally motivated their company's researching a home option of an isolation and containment unit. A.I.R. CEO Palmer states that he and Piscione leveraged decades of success in biomedical research and semiconductor clean-room technology to found American Innovative Research Corp. Palmer defines A.I.R. as a health and wellness technology company focused on providing advanced protection against airborne viruses. A.I.R. COO Piscione explains the I-Con™'s role in today 's H1N1 swine flu pandemic. Piscione describes the I-Con™ as a portable air purification and sterilization product for household, residential facility or institutional use. According to Piscione, their unit was specifically designed to reproduce the same airflow patterns that are used in hospitals and biological research facilities to create either isolation or containment. American Innovative Research Corp. is a Massachusetts, U.S.A. Company dedicated to the development of advanced technology for use in household and institutional airborne contamination purification and protection. SourceAmerican Innovative Research
Preclinical Proof-of-Concept Studies Published For Novavax Seasonal Influenza Virus-Like-Particle Vaccine
Novavax, Inc. (Nasdaq: NVAX) announced publication of the preclinical study results that supported the clinical development of the company's investigational VLP vaccine against the H3N2, H1N1 and B influenza strains. The study, which was conducted by scientists from the University of Pittsburgh, Center for Vaccine Research and Novavax, was published in the June 24, 2009 online issue of PLoS ONE. The vaccine contains three VLPs mixed together in a single formulation; each made up of the hemagglutinin (HA), neuraminidase (NA) and matrix 1 (M1) proteins from the representative strains. These proteins are important for broad protection against influenza, which is responsible for nearly 200,000 hospitalizations and 36,000 deaths in the U.S. each year. The vaccine is currently in Phase 2 clinical testing.In this study, mice and ferrets received intramuscular injections of VLP vaccine which induced HAI antibodies against all three influenza strains represented in the vaccine and against a variety of drifted strains. All of the ferrets who received a vaccine dose of 15 mcg/strain, the dose used for currently licensed vaccines, developed HAI titers greater than or equal to 1:40. This level of antibody has been shown to be important for protection against flu in human studies of influenza vaccines. In addition, approximately 50% of ferrets developed HAI titers greater than or equal to 1:40 against drifted H3N2 strains from the 1999, 2002, and 2005 influenza seasons. The vaccine was also protective, reducing the amount of influenza virus in the nose of ferrets that were challenged with the H3N2 strain from the 2005-6 season.In addition to antibody response, the study also examined cell-mediated immunity. T cell responses in mice vaccinated with the seasonal VLP vaccine were compared with T cell responses in mice vaccinated with a commercial influenza vaccine. Of note, mice vaccinated with the VLP vaccine had higher levels of HA flu-specific CD8+ T cells than mice vaccinated with the commercial vaccine. CD8+ T cells play a role in clearing virus from the respiratory tract, which may be an important factor in preventing influenza-associated pneumonia, a leading cause of flu-related hospitalizations in adults older than 65 years of age."This study demonstrates the breadth of the immune response induced by the VLP vaccine," said Ted Ross, Ph.D., Assistant Professor, Center for Vaccine Research, University of Pittsburgh. "Not only did the vaccine induce robust HAI responses, it also induced HA-specific CD8+ T cell responses that were superior to those of a split vaccine. This finding may be reflective of the integrity of the structure of the HA protein presented in the VLP.""We are pleased with the results of this study, which supported the human clinical trials of our seasonal influenza VLP vaccine," said Dr. Rahul Singhvi, president and CEO of Novavax. "We also observed robust HAI responses among subjects in the clinical trial of our seasonal flu vaccine, which we announced last December, including responses against drifted strains. We look forward to future studies to evaluate the breadth of the immune response induced by our VLP-based influenza vaccines."ABOUT NOVAVAXNovavax, Inc. (Nasdaq: NVAX) is a clinical-stage biotechnology company creating novel vaccines, including H1N1, to address a broad range of infectious diseases worldwide using advanced proprietary virus-like-particle (VLP) technology. The company produces these VLP-based, potent, recombinant vaccines utilizing new and efficient manufacturing approaches.Forward Looking StatementStatements herein relating to future financial or business performance, conditions or strategies and other financial and business matters, including expectations regarding revenues, operating expenses, cash burn, and clinical developments and anticipated milestones are forward-looking statements within the meaning of the Private Securities Litigation Reform Act. Novavax cautions that these forward-looking statements are subject to numerous assumptions, risks and uncertainties, which change over time. Factors that may cause actual results to differ materially from the results discussed in the forward-looking statements or historical experience include risks and uncertainties, including the Company's ability to progress any product candidates in preclinical or clinical trials; the scope, rate and progress of its preclinical studies and clinical trials and other research and development activities; clinical trial results; current results may not be predictive of future results; even if the data from preclinical studies or clinical trials is positive, the product may not prove to be safe and efficacious; Novavax's pilot plant facility is subject to extensive validation and FDA inspections, which may result in delays and increase d costs; our ability to enter into future collaborations with industry partners and the government and the terms, timing and success of any such collaboration; the cost of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; our ability to obtain rights to technology; competition for clinical resources and patient enrollment from drug candidates in development by other companies with greater resources and visibility; our ability to obtain adequate financing in the future through product licensing, co-promotional arrangements, public or private equity or debt financing or otherwise; the maturity of the convertible notes on July 15, 2009; general business conditions; competition; business abilities and judgment of personnel; and the availability of qualified personnel. Further information on the factors and risks that could affect Novavax's business, financial conditions and results of operations, is contained in Novavax's filings with the U.S.Source: Novavax, Inc
News From The Journals Of The American Society For Microbiology
Single-Shot" Vaccines May Protect Against H5N1 Influenza Virus Two newly developed "single-shot" H5N1 influenza vaccines protected ferrets against lethal infection with the H5N1 influenza virus and may allow for mass vaccination in humans in the event of a pandemic outbreak. The researchers from Australia report their findings in the August 2009 issue of the Journal of Virology. As the highly infectious H5N1 influenza A virus continues to persist in bird populations and infect humans through poultry, concerns of a pandemic outbreak remain high. Although human-to-human transmission has remained limited, the fatality rate among those reported human cases is greater than 60%. The threat that the virus will mutate and achieve efficient human-to-human spread emphasizes the need for effective preventative therapies. Vaccination is considered the optimal method for controlling an influenza pandemic. Vaccines must be rapidly available to reach mass populations and they must include the minimal antigen dose (substance that promotes the generation of antibodies) to result in full immunity. The use of adjuvants (substances to improve the immune response) in vaccine development may lower the antigen dose required and ultimately ease the demand on vaccine supply during a pandemic. Clinical trials on prepandemic vaccines containing adjuvant suggested that two injections were necessary to induce protective immunity. In this study researchers first inoculated ferrets twice with two H5N1 influenza virus adjuvant vaccines (Iscomatrix and AIPO4) and observed for protective efficacy following a lethal challenge with the H5N1 virus. Results showed that ferrets were completely protected against death and disease for at least 15 months. More significantly, a secondary study found that both adjuvant vaccines also protected ferrets from death following only a single inoculation. Specifically, ferrets receiving a single shot of the Iscomatrix adjuvant vaccine displayed fewer signs of infection and remained highly active. "Our data provide the first indication that in the event of a future influenza pandemic, effective mass vaccination may be achievable with a low-dose 'single shot' vaccine and provide not only increased survival but also significant reduction in disease severity," say the researchers. (D. Middleton, S. Rockman, M. Pearse, I. Barr, S. Lowther, J. Klippel, D. Ryan, L. Brown. 2009. Evaluation of vaccines for H5N1 influenza virus in ferrets reveals the potential for protective single-shot immunization. Journal of Virology, 83. 15: 7770-7778.) Infection-Causing Amoeba May be Resistant to Multiple Contact Lens Solutions A new study suggests that some contact lens solutions do not properly disinfect against Acanthamoeba, a free-living organism in the environment that can cause a painful vision-threatening infection. The researchers from the Centers for Disease Control and Prevention, Public Health Service, and the U.S. Department of Health and Human Services, Atlanta, Georgia, report their findings in the July 2009 issue of the Journal of Clinical Microbiology. Acanthamoeba are found in a variety of environmental sources including soil, freshwater, brackish water and seawater, as well as hot tubs and Jacuzzis. The species is associated with many different human diseases such as central nervous system infections and Acanthamoeba keratitis (AK), an infection of the cornea that can ultimately lead to blindness. 85% of AK cases in the United States are attributed to contact lens wear, with some specific risk factors being improper contact lens care and contact with nonsterile water during wear. Insufficient anti-Acanthamoeba activity in Advanced Medical Optics Complete MoisturePlus multipurpose contact lens solution was brought to attention following a recent multistate outbreak of AK. While investigating that outbreak, researchers also compared the effectiveness of 11 other contact lens solutions against cysts of Acanthamoeba castellanii, Acanthamoeba polyphaga, and Acanthamoeba hatchetti, all of which were sample specimens collected during the outbreak. Results indicated that only the two contact lens solutions containing hydrogen peroxide showed any disinfection ability against A. castellanii and A. polyphaga after 6 or 24 hours. No significant disinfection efficacy was noted among the 11 solutions against A. hatchetti. "The prevention of future cases of AK will require contact lens solutions that are effective against Acanthamoeba species and continued emphasis on proper lens care hygiene," say the researchers. "Educating contact lens wearers about the risk factors for AK, including the improper use of contact lens solutions, is important; but a systematic method for evaluating contact lens solutions will reduce the chance that inefficacious solutions are available." (S.P. Johnston, R. Sriram, Y. Ovarnstrom, S. Roy, J. Verani, J. Yoder, S. Lorick, J. Roberts, M.J. Beach, G. Visvesvara. 2009. Resistance of Acanthamoeba cysts to disinfection in multiple contact lens solutions. Journal of Clinical Microbiology, 47. 7: 2040-2045.) New DNA Vaccine Inhibits Deadly Skin Cancer in Mice A new DNA vaccine inhibited malignant melanoma, a deadly form of skin cancer, in mice by eliciting antibodies that target a gastrin-releasing peptide which is known to play a key role in cancer development. The researchers from China and the U.S. report their findings in the July 2009 issue of the journal Clinical and Vaccine Immunology. Gastrin-releasing peptide (GRP) is an important human peptide that regulates gastric acid secretion and motor function as well as elicits gastrin release. Previous research has shown that GRP plays a significant role in human cancers through atypical expression of the GRP receptor and GRP binding that activates cellular signaling and results in increased cell production and tumor formation. Anti-GRP antibodies have displayed promising antitumoral activity and DNA vaccines targeting GRP are a hopeful therapeutic approach. In the study researchers developed a novel anti-GRP DNA vaccine including various immunoadjuvants (substances to improve the immune response) and monitored anti-GRP antibody levels in vaccinated mice. Intramuscular injections induced high levels of specific antibodies against GRP as well as suppressed the growth of melanoma cells. Additionally, researchers intravenously injected cells in the lungs and found that cells were highly diminished indicating that the vaccine may also inhibit cancer from spreading. "In conclusion, we have demonstrated for the first time that immune responses which are elicited by a novel anti-GRP DNA vaccine suppress the proliferation and growth of melanoma tumors in mice," say the researchers. "The antiangiogenesis and antimetastastic activities of this DNA vaccine suggest a novel approach against various cancers, especially malignant melanoma." (J. Fang, Y. Lu, K. Ouyang, G. Wu, H. Zhang, Y. Liu, Y. Chen, M. Lin, H. Wang, L. Jin, R. Cao, R.S. Roque, L. Zong, J. Liu, T. Li. 2009. Specific antibodies elicited by a novel DNA vaccine targeting gastrin-releasing peptide inhibit murine melanoma growth in vitro. Clinical and Vaccine Immunology, 16. 7: 1033-1039.) Source: Carrie Slijepcevic American Society for Microbiology
Filter-Feeding Bivalves Can Remove Avian Influenza Viruses From Water And Reduce Infectivity
Avian influenza (AI) viruses are believed to be transmitted within aquatic bird populations through contaminated water. This study determined that filter-feeding clams can remove AI virus from water and reduce infectivity.Wood ducks were inoculated with a variety of treatments, and none of the ducks inoculated with virus-infected water that was filtered by clams or that were inoculated with or fed tissue from these clams exhibited signs of infection.These results indicate that filter-feeding bivalves can remove AI viruses from water, and demonstrate the need to examine the little-understood biotic environmental factors that can influence AI virus transmission.
Subscribe to:
Posts (Atom)