May 11, 2008, 9:08 AM CT

UV lotion lights the way to cleaner facilities

A team of Canadian researchers using a lotion which glows under ultraviolet light have shown that up to a third of patient toilets are not properly cleaned. Their findings, published in BioMed Centrals journal, BMC Infectious Diseases, also show that spores from the nasty bacteria Clostridium difficile (C. difficile) linger in the loo even when it has been thoroughly wiped down.

Michelle Alfa and a team of researchers from Manitoba, Canada investigated the spread of so-called superbugs in hospitals. Hospital patients are thought to catch bugs like vancomycin resistant Enterococci (VRE), methicillin resistant Staphylococcus aureus (MRSA) and C. difficile because they are not eradicated from the hospital environment. These bugs may be transferred between patients through cross-contamination in the bathroom.

Various studies have looked at the most effective cleaning agents, but none of these studies considered whether housekeeping staff were actually cleaning the toilets properly, says Alfa. It is impossible to assess the effectiveness of any action against these bacteria unless you can be sure that cleaners comply with protocols.

Alfa's toilet inspectors smeared the UV lotion under the seats of 20 toilets and commodes being used by patients with diarrhoea at a hospital in Winnipeg. Seven of these patients had C. difficile infection, while 13 others did not. The toilets and commodes were tested every weekday for six months and checked using UV light to determine how well they had been cleaned. In addition, samples were taken from toilet surfaces to determine whether C difficile spores were present......... Posted by: Mark      Read more         Source

May 8, 2008, 9:11 PM CT

Major shift in HIV prevention priorities needed

As per a new policy analysis led by scientists at the Harvard School of Public Health (HSPH) and the University of California, Berkeley, the most common HIV prevention strategiescondom promotion, HIV testing, therapy of other sexually transmitted infections (STIs), vaccine and microbicide research, and abstinenceare having a limited impact on the predominantly heterosexual epidemics found in Africa. Furthermore, some of the assumptions underlying such strategiessuch as poverty or war being major causes of AIDS in Africaare unsupported by rigorous scientific evidence. The scientists argue that two interventions currently getting less attention and resourcesmale circumcision and reducing multiple sexual partnershipswould have a greater impact on the AIDS pandemic and should become the cornerstone of HIV prevention efforts in the high-HIV-prevalence parts of Africa.

The paper appears in the May 9, 2008 issue of the journal Science.

Despite relatively large investments in AIDS prevention efforts for some years now, including sizeable spending in some of the most heavily affected countries (such as South Africa and Botswana), its clear that we need to do a better job of reducing the rate of new HIV infections. We need a fairly dramatic shift in priorities, not just a minor tweaking, said Daniel Halperin, lecturer on international health in the HSPH Department of Population and International Health and one of the papers lead authors......... Posted by: Janet      Read more         Source

May 5, 2008, 9:19 PM CT

Immune exhaustion in HIV infection

Its the virus, stupid: immune exhaustion in HIV infection

As HIV disease progresses in a person infected with the HIV virus, a group of cells in the immune system, the CD8+ T lymphocytes, become exhausted, losing a number of of their abilities to kill other cells infected by the virus. For a number of years researchers have debated whether this exhaustion of CD8+ T cells is the cause, or the consequence, of persistence of the HIV virus. As per a research findings published this week in PLoS Medicine, Marcus Altfeld and his colleagues studied the immune response over time amongst 18 individuals who had very recently become infected with HIV.

These scientists observed that the presence of high amounts of HIV in the blood seemed to cause CD8+ T cell exhaustion; when antigen was reduced, either as a result of therapy with antiretroviral drugs, or evolution of viral epitopes to avoid recognition by CD8+ T cells, these epitope-specific CD8+ T cells recovered some of their original functions. These findings suggest that CD8+ T cell exhaustion is the consequence, rather than the cause, of persistent replication of HIV.

In a related article, Sarah Rowland-Jones and Thushan de Silva (from the Medical Research Council in Gambia), who were not involved in the study, discuss approaches to treat HIV efficiently by suppressing the viral load early in infection aimed at preserving HIV-1-specific immune function. They evaluate whether such strategies are likely to be practical......... Posted by: Mark      Read more         Source

April 30, 2008, 5:32 PM CT

How some bacteria survive antibiotics

Scientists at the University of Illinois at Chicago have discovered how some bacteria can survive antibiotic therapy by turning on resistance mechanisms when exposed to the drugs. The findings, reported in the April 24 issue of the journal Molecular Cell, could lead to more effective antibiotics to treat a variety of infections.

"When patients are treated with antibiotics some pathogenic microbes can turn on the genes that protect them from the action of the drug," said Alexander Mankin, professor and associate director of the University of Illinois at Chicago's Center for Pharmaceutical Biotechnology and lead investigator of the study. "We studied how bacteria can feel the presence of erythromycin and activate production of the resistance genes".

Erythromycin and newer macrolide antibiotics azithromycin and clarithromycin are often used to treat respiratory tract infections, as well as outbreaks of syphilis, acne and gonorrhea. The drugs can be used by patients allergic to penicillin.

Macrolide antibiotics act upon the ribosomes, the protein-synthesizing factories of the cell. A newly-made protein exits the ribosome through a tunnel that spans the ribosome body. Antibiotics can ward off an infection by attaching to the ribosome and preventing proteins the bacterium needs from moving through the tunnel......... Posted by: Mark      Read more         Source

April 6, 2008, 8:26 PM CT

Alligator blood for antibiotic-resistant infections

Despite their reputation for deadly attacks on humans and pets, alligators are wiggling their way toward a new role as potential lifesavers in medicine, biochemists in Louisiana reported today at the 235th national meeting of the American Chemical Society. They described how proteins in gator blood may provide a source of powerful new antibiotics to help fight infections linked to diabetic ulcers, severe burns, and superbugs that are resistant to conventional medication.

Their study, described as the first to explore the antimicrobial activity of alligator blood in detail, found a range of other promising uses for the gators antibiotic proteins. Among them: combating Candida albicans yeast infections, which are a serious problem in AIDS patients and transplant recipients, who have weakened immune systems, the researchers say.

Were very excited about the potential of these alligator blood proteins as both antibacterial and antifungal agents, says co-author of study Mark Merchant, Ph.D., a biochemist at McNeese State University in Lake Charles, La. Theres a real possibility that you could be treated with an alligator blood product one day.

Prior studies by Merchant showed that alligators have an uncommonly strong immune system that is very different from that of humans. Unlike people, alligators can fight microorganisms such as fungi, viruses, and bacteria without having previous exposure to them. Researchers think that this is an evolutionary adaptation to promote quick wound healing, as alligators are often injured during fierce territorial battles......... Posted by: Mark      Read more         Source

March 24, 2008, 7:50 PM CT

Dramatic Rise in Hepatitis C-Related Deaths in the United States

Hepatitis C-related deaths in the United States increased by 123 percent from 1995 through 2004, the most recent year for which data are available. Mortality rates peaked in 2002, then declined slightly overall, while continuing to rise among people 55 to 64 years old. These findings are reported in the recent issue of Hepatology, a journal of the American Association for the Study of Liver Diseases (AASLD). The article is also available online at Wiley Interscience (www.interscience.wiley.com).

Hepatitis C virus (HCV) is the most common blood-borne infection in the United States, affecting about 1.3 percent of the population. Up to one-in-five sufferers develop liver cirrhosis, and up to one-in-20 develop liver cancer. HCV is the top reason for liver transplantation, and the 16th leading cause of premature death in the country. Recent evidence has suggested that disease burden and mortality from chronic HCV infection may increase in the coming years, as the number of persons with longstanding infections continues to rise.

To update estimates of trends and demographics of hepatitis C-related mortality in the U.S., a team of scientists led by Matthew Wise of UCLA and including scientists from the CDC and the Los Angeles County Department of Public Health analyzed mortality rates derived from U.S. Census and multiple-cause-of-death data from 1995-2004. They included 56,409 HCV related deaths, including those for which the disease was the underlying cause; those for which chronic liver disease was the underlying cause and hepatitis C was a contributing cause; and those for which HIV was the underlying cause and chronic liver disease and hepatitis C were contributing causes......... Posted by: Mark      Read more         Source

March 13, 2008, 8:44 PM CT

How diabetes drives atherosclerosis

Scientists have discovered how diabetes, by driving inflammation and slowing blood flow, dramatically accelerates atherosclerosis, as per research would be reported in the March 14 edition of the journal Circulation Research.

Experts once believed that atherosclerosis, or hardening of the arteries, developed when too much cholesterol clogged arteries with fatty deposits called plaques. When blood vessels became completely blocked, heart attacks and strokes occurred. Today most agree that the reaction of the body's immune system to fatty build-up, more than the build-up itself, creates heart attack risk. Immune cells traveling with the blood mistake fatty deposits for intruders, akin to bacteria, home in on them, and attack. This causes inflammation that makes plaques more likely to swell, rupture and cut off blood flow.

Making matters worse, nearly 21 million Americans have diabetes, a disease where patients cells cannot efficiently take in dietary sugar, causing it to build up in the blood. In part because diabetes increases atherosclerosis-related inflammation, diabetic patients are twice as likely to have a heart attack or stroke.

Past work has shown that high blood sugar has two effects on cells lining blood vessels as part of atheroslerosis. First, it increases the production of free radicals, highly reactive molecules that tear about sensitive cell components like DNA, causing premature cell death (apoptosis). This process also reduces the availability of nitric oxide (NO), which would otherwise enable blood vessels to relax and blood flow to increase. In contrast to diabetes, exercise and good diet bring about faster blood flow through blood vessels. The force created by fast, steady blood flow as it drags along blood vessel walls has been shown by recent studies to protect arteries from atherosclerosis. Physical force has emerged recently as a key player in bodily function, capable of kicking off biochemical processes (e.g. weightlifting thickens bone)......... Posted by: Mark      Read more         Source

March 9, 2008, 5:02 PM CT

New bacteria contaminate hairspray

Researchers in Japan have discovered a new species of bacteria that can live in hairspray, as per the results of a study reported in the recent issue of the International Journal of Systematic and Evolutionary Microbiology.

Contamination of cosmetic products is rare but some products may be unable to suppress the growth of certain bacteria, says Dr Bakir from the Japan Collection of Microorganisms, Saitama, Japan. We discovered a new species of bacteria called Microbacterium hatanonis, which we found contaminates hairspray.

We also found a related species, Microbacterium oxydans in hairspray which was originally isolated from hospital material. Microbacterium species have been identified in milk, cheese, beef, eggs and even in the blood of patients with leukaemia, on catheters and in bone marrow.

The researchers looked at the appearance and diet of the bacterium, then analysed its genome to show that it is an entirely new species. It has been named in honour of Dr Kazunori Hatano, for his contribution to the understanding of the genus Microbacterium, says Dr Bakir. Microbacterium hatanonis is rod-shaped and grows best at 30C and pH neutral.

Researchers now need to determine the clinical importance of the new species, as similar bacteria have been found to infect humans. Further testing will establish whether the species is a threat to human health, says Dr Bakir. We hope our study will benefit the formulation of hairspray to prevent contamination in the future......... Posted by: Mark      Read more         Source

March 5, 2008, 8:23 PM CT

Knock-out Punch For Antibiotic Resistance

MIT graduate student and synthetic biologist Timothy Lu is passionate about tackling problems that pose threats to human health. His current mission: to destroy antibiotic-resistant bacteria.

Today, the 27-year-old M.D. candidate and Ph.D. in the Harvard-MIT Division of Health Sciences and Technology received the prestigious $30,000 Lemelson-MIT Student Prize for inventing processes that promise to combat bacterial infections by enhancing the effectiveness of antibiotics at killing bacteria and helping to eradicate biofilm - bacterial layers that resist antimicrobial therapy and breed on surfaces, such as those of medical, industrial and food processing equipment.

Bacterial infections can lead to severe health issues. The Centers for Disease Control and Prevention estimates that the antibiotic-resistant bacterium MRSA, or methicillin-resistant Staphylococcus aureus, causes approximately 94,000 infections and contributes to 19,000 deaths annually in the United States, through contact that can occur in a variety of locations, including schools, hospitals and homes. Bacteria can also infect food, including spinach and beef, and damage industrial equipment.

Lu explained that fewer pharmaceutical companies are inventing new antibiotics due to long development times, high failure rates and large costs. As per the Tufts Center for the Study of Drug Development, the cost to develop a new drug is $930 million (based on the value of the dollar in 2006). These factors, coupled with a decline in the number of prescriptions authorized for antibiotics, constrain profits. "Antibiotic-resistant bacteria are also becoming more prevalent," Lu noted. "My inventions enable the rapid design and production of inexpensive antibacterial agents that can break through the defenses of antibiotic-resistant bacteria and bacterial biofilms"......... Posted by: Mark      Read more         Source

March 4, 2008, 5:35 PM CT

Study uncovers cause of flu epidemics

The exchange of genetic material between two closely related strains of the influenza A virus may have caused the 1947 and 1951 human flu epidemics, as per biologists. The findings could help explain why some strains cause major pandemics and others lead to seasonal epidemics.

Until now, it was believed that while reassortment when human influenza viruses swap genes with influenza viruses that infect birds causes severe pandemics, such as the Spanish flu of 1918, the Asian flu of 1957, and the Hong Kong flu of 1968, while viral mutation leads to regular influenza epidemics. But it has been a mystery why there are sometimes very severe epidemics like the ones in 1947 and 1951 that look and act like pandemics, even though no human-bird viral reassortment event occurred.

There was a total vaccine failure in 1947. Scientists initially thought there was a problem in manufacturing the vaccine, but they later realized that the virus had undergone a tremendous evolutionary change, said Martha Nelson, lead author and a graduate student in Penn States Department of Biology. We now believe that the 1947 virus did not just mutate a lot, but that this unusual virus was made through a reassortment event involving two human viruses.

So we have observed that the bipolar way of looking at influenza evolution is incorrect, and that reassortment can be an important driver of epidemic influenza as well as pandemic influenza, said Nelson, whose teams findings are reported in the current issue of PLoS Pathogens. We have discovered that you can also have reassortment between viruses that are much more similar, that human viruses can reassort with each other and not just with bird viruses......... Posted by: Mark      Read more         Source

March 4, 2008, 4:54 PM CT

PANTHER sensor quickly detects pathogens

Scientists at MIT Lincoln Laboratory have developed a powerful sensor that can detect airborne pathogens such as anthrax and smallpox in less than three minutes.

The new device, called PANTHER (for PAthogen Notification for THreatening Environmental Releases), represents a "significant advance" over any other sensor, said James Harper of Lincoln Lab's Biosensor and Molecular Technologies Group. Current sensors take at least 20 minutes to detect harmful bacteria or viruses in the air, but the PANTHER sensors can do detection and identification in less than 3 minutes.

The technology has been licensed to Innovative Biosensors, Inc. (IBI) of Rockville, Md. In January, IBI began selling a product, BioFlash, that uses the PANTHER technology.

"There is a real need to detect a pathogen in less than three minutes, so you have time to take action before it is too late," said Harper, the lead scientist developing the sensor.

The PANTHER sensor uses a cell-based sensor technology known as CANARY (after the birds sent into mines to detect dangerous gases), and can pick up a positive reading with only a few dozen particles per liter of air.

The device could be used in buildings, subways and other public areas, and can currently detect 24 pathogens, including anthrax, plague, smallpox, tularemia and E. coli......... Posted by: Mark      Read more         Source

February 26, 2008, 10:24 PM CT

Bacterial 'battle for survival' leads to new antibiotic

Biologists have provoked soil-dwelling bacteria into producing a new type of antibiotic by pitting them against another strain of bacteria in a battle for survival.

The antibiotic holds promise for therapy of Helicobacter pylori, which causes stomach ulcers in humans. Also, figuring out the still murky explanation for how the new antibiotic was produced could help researchers develop strategies for finding other new antibiotics.

The work is published in the recent issue of the Journal of the American Chemical Society.

A combination of luck, patience and good detective work contributed to the discovery of the new antibiotic, as per Philip Lessard, research scientist in Professor Anthony Sinskey's laboratory at MIT.

Sinskey's lab has been studying Rhodococcus, a type of soil-dwelling bacteria, for a number of years. While sequencing the genome of one Rhodococcus species, the scientists noticed that a large number of genes seemed to code for secondary metabolic products, which are compounds such as antibiotics, toxins and pigments.

However, Rhodococcus does not normally produce antibiotics. A number of bacteria have genes for antibiotics that are only activated when the bacteria are threatened in some way, so the scientists suspected that might be true of Rhodococcus......... Posted by: Mark      Read more         Source

February 26, 2008, 4:55 PM CT

Tropics Are Next Emerging Disease Hotspot

Researchers from four well-known institutions say the next major disease like HIV/AIDS or SARS could occur in any of many developing countries concentrated along the equator. They encourage increased surveillance to prevent the spread of a potential outbreak.

Using global databases and sophisticated computer models to analyze patterns of emerging diseases, the scientists -- from the Consortium for Conservation Medicine (CCM) at Wildlife Trust, N.Y., the Institute of Zoology, London, U.K., Columbia University, N.Y., and the University of Georgia, Athens, Ga. -- are able for the first time to plot, map and predict where the next pandemic might occur.

Funded through a Human and Social Dynamics Exploratory Research award from the National Science Foundation (NSF), Arlington, Va., the research represents a major breakthrough in understanding where and why pandemic diseases emerge and provides a key tool for preventing them in the future.

"This is an important area of research," said Rita Teutonico, advisor for integrative activities in NSF's Directorate for Social, Behavioral and Economic Sciences. "After years of debate, the scientific community is now able to offer a convincing, predictive tool to help policy professionals and resource managers better allocate global resources in the fight against emerging diseases"......... Posted by: Mark      Read more         Source

February 25, 2008, 8:54 PM CT

Women With HIV Want To Become Pregnant

About one in four women who have tested positive for the human immunodeficiency virus (HIV) expect pregnancy and motherhood to be a part of their future, recent research suggests.

A woman's age at the time she learns of her HIV status appears to influence this decision. Women in an Ohio State University study who learned of their HIV infection when they were under age 30 were almost four times more likely to say they wanted to become pregnant than were women who were over 30 when they learned they had HIV.

Scientists say the findings point to a need for clinicians to be aware that women with HIV might be struggling with decisions about motherhood - a relatively new phenomenon accompanying the increase in HIV-positive women of childbearing age and the longer survival rates among patients who receive therapy.

"We shouldn't assume that women aren't going to become pregnant or don't want to become pregnant now that they have HIV. That's an erroneous assumption," said co-author of study Julianne Serovich, professor and chair of human development and family science at Ohio State. "Clinicians should be routinely discussing pregnancy with HIV-positive women of childbearing age".

In 2005, 29.5 percent of all new reported HIV infections and 27 percent of new AIDS cases in the United States were among women, as per the Centers for Disease Control and Prevention. Twenty years earlier, only 5 percent of new AIDS cases were reported in women. HIV is the virus that causes AIDS......... Posted by: Mark      Read more         Source

February 14, 2008, 10:28 PM CT

Novel approach strips staph of virulence

An international team of scientists supported by the National Institutes of Health (NIH) has blocked staph infections in mice using a drug previously tested in clinical trials as a cholesterol-lowering agent. The novel approach, described in the February 14 online edition of Science, could offer a new direction for therapies against a bacterium thats becoming increasingly resistant to antibiotics.

By following their scientific instinct about a basic biological process, the scientists made a surprising discovery with important clinical implications, said NIH Director Elias A. Zerhouni, M.D. Eventhough the results are still very preliminary, they offer a promising new lead for developing drugs to treat a very timely and medically important health concern.

This work was supported by three NIH components: the National Institute of General Medical Sciences, the National Institute of Allergy and Infectious Diseases, and the National Institute of Child Health and Human Development.

A pigment similar to the one that gives carrots their color turns Staphylococcus aureus (staph) golden. In the bacterium, this pigment acts as an antioxidant to block the reactive oxygen molecules the immune system uses to kill bacteria.

Scientists had speculated that blocking pigment formation in staph could restore the immune systems ability to thwart infection. While perusing a magazine on microbial research, Eric Oldfield, Ph.D., of the University of Illinois at Urbana-Champaign read how in 2005 University of California, San Diego scientists knocked out a gene in staphs pigment-making pathway to create colorlessand less pathogenicbacteria......... Posted by: Mark      Read more         Source

February 13, 2008, 9:20 PM CT

Vaccine for stomach flu may be possible

Every year, millions of people are infected with noroviruses - usually called stomach flu often resulting in up to 72 hours of vomiting and diarrhea. While most people recover in a few days, the symptoms can lead to dehydration and - in rare cases, particularly among the elderly and infants - death.

Now, scientists at the University of North Carolina School of Public Health have discovered that the virus mutates genetically, similar to the virus that causes influenza. And, like flu, a vaccine could be possible.

One of the mysteries of medicine has been why do they keep infecting people when youd think wed be developing immunity, said Lisa Lindesmith, one of the lead authors of the study, Mechanisms of GII.4 Norovirus Persistence in Human Populations, published recently in the online medical journal PLoS Medicine. What weve found is that the GII.4 arm [of the noroviruses] keeps changing. Whenever were seeing big outbreaks of norovirus, were also seeing genetic changes in the virus.

Noroviruses are the leading cause of viral acute gastroenteritis. They are highly contagious, often causing epidemic outbreaks in families and communities, on cruise ships, in hospitals and in assisted living facilities. The viruses are particularly hard on the elderly in 2006, 19 deaths were linked to norovirus acute gastroenteritis in long-term care facilities in the United States. Often, infection can mean a number of miserable hours, with time lost from work, school and other activities. There is no therapy to stop the infection......... Posted by: Mark      Read more         Source

February 13, 2008, 9:19 PM CT

HIV persists in the gut despite long-term therapy

Even with effective anti-HIV therapies, doctors still have not been able to eradicate the virus from infected individuals who are receiving such therapys, largely because of the persistence of HIV in hideouts known as viral reservoirs. One important reservoir is the gut, where HIV causes much of its damage due to the large number of HIV target cells that reside there. These cells, known as CD4+ T cells, are largely contained in lymph nodes and patches of lymphocytes that collectively are called gut-associated lymphoid tissue, or GALT.

Because of the importance of the gut to HIV disease, researchers hoped that long-term therapy with antiretroviral drugs could eradicate HIV from the GALT. A new NIAID study, published online by The Journal of Infectious Diseases, has observed that this goal seems unlikely with current antiretroviral drugs.

Tae-Wook Chun, Ph.D., of the NIAID Laboratory of Immunoregulation (LIR), Anthony S. Fauci, M.D., LIR chief and NIAID director, and their colleagues intensively studied eight patients receiving effective antiretroviral treatment for up to 9.9 years. In each of these of these individuals, treatment had consistently kept their blood levels of HIV at undetectable levels. Sensitive tests, however, detected the persistence of HIV as well as lowered CD4+ T cell levels in the GALT that did not completely rebound in response to treatment. Levels of virus were higher in the GALT than in immune cells in the blood, where HIV also was consistently found. In addition, the researchers found evidence of cross infection between the GALT and the lymphocytes in the blood, suggesting that one reason the virus persists in the blood is because of ongoing cycles of replication in the GALT. The authors conclude that any possibility of further lowering or eliminating viral reservoirs likely will require more powerful drug regimens to stop the low levels of ongoing viral replication originating in the GALT. The development of such regimens is an important goal of NIAID-supported research......... Posted by: Mark      Read more         Source

February 6, 2008, 5:24 AM CT

Novel Molecules Can Boost Vaccine Potency

Two novel proteins studied by a University at Buffalo professor of microbiology and immunology appear to have the potential to enhance the production of antibodies against a multitude of infectious agents.

Terry D. Connell, Ph.D., professor of microbiology and immunology in the Witebsky Center for Microbial Pathogenesis in the UB School of Medicine and Biomedical Sciences, developed and patented the LT-IIa and LT-IIb enterotoxins and their respective mutant proteins as new mucosal adjuvants, or "boosters," that can enhance the potency of existing and future vaccines.

Connell and his colleagues published five papers in 2007 describing their advances. They are the only research group in the scientific community investigating the immunology of these adjuvants.

The scientists currently are working to develop a safe and effective method to deliver the immune-enhancing molecules to the body's mucous membranes -- the first line of defense against most pathogens -- to elicit protective immune responses on those membranes.

"Almost every bacterium and virus that attacks us doesn't bore through the skin," said Connell. "These infectious agents enter by colonizing the mucosal surfaces on the eye, sinuses, mouth, gut lining, lungs and genital tract."........ Posted by: Mark      Read more         Source

February 4, 2008, 9:50 PM CT

Grapefruit compound may help combat hepatitis C

A compound that naturally occurs in grapefruit and other citrus fruits may be able to block the secretion of hepatitis C virus (HCV) from infected cells, a process mandatory to maintain chronic infection. A team of scientists from the Massachusetts General Hospital Center for Engineering in Medicine (MGH-CEM) report that HCV is bound to very low-density lipoprotein (vLDL, a so-called bad cholesterol) when it is secreted from liver cells and that the viral secretion mandatory to pass infection to other cells may be blocked by the common flavonoid naringenin.

If the results of this study extend to human patients, a combination of naringenin and antiviral medicine might allow patient to clear the virus from their livers. The report will appear in an upcoming issue of the journal Hepatology and has been released online.

By finding that HCV is secreted from infected cells by latching onto vLDL, we have identified a key pathway in the viral lifecycle, says Yaakov Nahmias, PhD, of the MGH-CEM, the papers lead author. These results suggest that lipid-lowering drugs, as well as supplements, such as naringenin, may be combined with traditional antiviral therapies to reduce or even eliminate HCV from infected patients.

HCV is the leading cause of chronic viral liver disease in the United States and infects about 3 percent of the world population. Current antiviral medications are effective in only half of infected patients, 70 percent of whom develop chronic infection that can lead to cirrhosis or liver cancer. Since the virus does not integrate its genetic material into the DNA of infected cells the way HIV does, totally clearing the virus could be possible if new cells were not being infected by secreted virus......... Posted by: Mark      Read more         Source

February 4, 2008, 8:42 PM CT

2009 Bush budget a disaster for HIV/AIDS

The Presidents proposed budget for fiscal year 2009, if enacted, would spell disaster for the nations health, and by extension, our national effort to respond to the HIV/AIDS epidemic in the United States.

The Administrations budget flat-funds critical federal support for research at the National Institutes of Health (NIH), public health programs at the Centers for Disease Control and Prevention (CDC), and vital health care safety net programs funded through the Health Resources and Services Administration (HRSA) and the Medicaid program. After accounting for inflation, the budget proposal amounts to a cut in funding for HIV/AIDS research, prevention, care, and therapy.

Adding insult to injury, the budget proposal increases funding for abstinence education programs that have no basis in scientific evidence, an irresponsible policy with potentially deadly consequences. Failure to adequately support evidence-based prevention programs diminishes our capacity to monitor the epidemic, to expand HIV screening to identify those who are already infected but unaware of their status, and to prevent new infections through targeted programs directed to high-risk populations.

Cutting federal Medicaid funding during the current economic downturn when states are struggling to maintain their programs will only result in reductions in eligibility and vital medical services for this essential health care safety net program that provides more financing for HIV care than any other source. The impact of these proposed cuts will undoubtedly fall on the most vulnerable among usthe poor, the elderly, the chronically ill, and those living with disabilities......... Posted by: Mark      Read more         Source

January 21, 2008, 8:34 PM CT

Studies highlight MRSA evolution and resilience

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are caused primarily by a single strainUSA300of an evolving bacterium that has spread with extraordinary transmissibility throughout the United States during the past five years, as per a new study led by National Institutes of Health (NIH) scientists. CA-MRSA, an emerging public health concern, typically causes readily treatable soft-tissue infections such as boils, but also can lead to life-threatening conditions that are difficult to treat.

The study, from the National Institute of Allergy and Infectious Diseases (NIAID) of NIH, resolves debate about the molecular evolution of CA-MRSA in the United States. The findings rule out the previously held possibility that multiple strains of USA300, the most troublesome type of CA-MRSA in the United States, emerged randomly with similar characteristics. The study also offers a hypothesis for the origin of prior S. aureus outbreaks, such as those caused by penicillin-resistant strains in the 1950s and 1960s.

A second study led by the same NIAID researchers takes the issue of the evolution of MRSA a step further, revealing new information about how MRSA bacteria in general, including the USA300 group, elude the human immune system......... Posted by: Mark      Read more         Source

January 6, 2008, 10:08 PM CT

Key factor in flu infection

Researchers have identified a key factor that determines the ability of influenza viruses to infect cells of the human upper respiratory tracta necessary step for sustaining spread between people. The research, described in the January 6 online edition of Nature Biotechnology and funded by the National Institutes of Health (NIH), offers new insights into how the H5N1 avian flu virus currently circulating in birds would have to change in order to gain a foothold in human populations.

The H5N1 virus has infected several hundred people, but person-to-person transmission has been limited. To trigger a widespread outbreak, experts agree that the bird flu virus must infect the cells lining our noses and throats. We then would spread the virus to others through coughing or sneezing. The latest study, led by Ram Sasisekharan, Ph.D., of the Massachusetts Institute of Technology in Cambridge, refines this notion: The virus can gain access only through a subset of the sugar molecules coating the cells of our upper airways.

"Using an approach that combines experimentation and database analysis, Sasisekharans team has changed our view of flu viruses and how they must adapt to infect us, said Jeremy M. Berg, Ph.D., director of the National Institute of General Medical Sciences, the NIH component that supported the research. The work may improve our ability to monitor the evolution of the H5N1 virus and thwart potential outbreaks......... Posted by: Mark      Read more         Source

December 20, 2007, 5:15 AM CT

Breakthrough in rapid malaria detection

A research team led by Dr. Paul Wiseman of the Departments of Physics and Chemistry at McGill University has developed a radically new technique that uses lasers and non-linear optical effects to detect malaria infection in human blood, as per a research studyreported in the Biophysical Journal. The scientists say the new technique holds the promise of simpler, faster and far less labour-intensive detection of the malaria parasite in blood samples.

Malaria is a vector-borne infectious disease spread by parasites of the genus Plasmodium. Most common in tropical and subtropical regions, it is a global scourge with 350 to 500 million new cases and one to three million fatalities reported annually. Most of the fatalities are concentrated in sub-Saharan Africa, where the resources and trained personnel currently mandatory to accurately diagnose the disease are spread the thinnest.

Current detection techniques require trained technicians to stain slides, look for the parasites DNA signature under the microscope, and then manually count all the visible infected cells, a labourious process dependent on the skill and availability of trained analysts. By contrast, the proposed new technique relies on a known optical effect called third harmonic generation (THG), which causes hemozoin a crystalline substance secreted by the parasite to glow blue when irradiated by an infrared laser......... Posted by: Mark      Read more         Source

December 17, 2007, 10:17 PM CT

Protecting aging Americans against infectious disease

Scientists at Oregon Health & Science University have uncovered new information about the bodys immune system in a study that suggests new strategies may be in order for protecting the countrys aging population against disease. The research is reported in the current edition of the Proceedings of the National Academy of Science.

The research focused on an important component of the bodys immune system, a certain type of white blood cell called nave T-cells. These cells are called naive because they have no experience of encountering germs. However, once they encounter germs, they learn and adapt to become strong defenders of the organism. The cells play an important role in the vaccination process because vaccines, which contain either weakened or dead viruses, teach nave T-cells how to recognize germs and prepare the body for fighting infectious diseases at a later date. Prior research shows that an individuals supply of nave T-cells diminishes over their lifetime, meaning that in old age a person is more susceptible to infections such as the flu.

Our research identified one actual process by which nave T-cells are lost during the later part of life, explained Janko Nikolich-Zugich, Ph.D., a senior scientist at the OHSU Vaccine and Gene Therapy Institute and the Oregon National Primate Research Center and a professor of molecular microbiology and immunology in the OHSU School of Medicine......... Posted by: Mark      Read more         Source