MedicineWorld.Org
Your gateway to the world of medicine
Home
News
Cancer News
About Us
Cancer
Health Professionals
Patients and public
Contact Us
Disclaimer

Medicineworld.org: Archives of infectious disease blog


Go Back to the main infectious disease blog

Subscribe To Health Blog RSS Feed  RSS content feed What is RSS feed?

Archives Of Infectious Disease Blog From Medicineworld.Org


May 23, 2007, 9:54 PM CT

Botulism bug has few genome wrinkles

Botulism bug has few genome wrinkles
The genome of the organism that produces the world's most lethal toxin is revealed today. This toxin is the one real weapon in the genome of Clostridium botulinum and less than 2 kg - the weight of two bags of sugar - is enough to kill every person on the planet. Very small amounts of the same toxin are used in medical therapys, one of which is known as Botox.

The genome sequence, reported in Genome Research, shows that C. botulinum doesn't have subtle tools to evade our human defences or tricky methods of acquiring resistance to antibiotics. It lives either as a dormant spore or as a scavenger of decaying animal materials in the soil, and doesn't interact with human or other large animal hosts for prolonged periods of time.

Occasionally it gets into a living animal, via contaminated food or open wounds, leading to infant botulism or wound botulism, both of which are serious human infections. The host can be quickly overpowered and, in some cases, killed by the toxin, and C. botulinum has a new food source.

"Eventhough in the same group as Clostridium difficile - the Cdiff superbug - C. botulinum has a genome that is remarkable because it is so stable, "commented Dr Mohammed Sebaihia, lead author on the paper from the Wellcome Trust Sanger Institute. "Unlike Cdiff, in which more than 10% of genes have been acquired from other bacteria, there is almost no footprint of these in C. botulinum".........

Posted by: Scott      Read more         Source


May 21, 2007, 10:31 AM CT

Soldiers acquired drug-resistant infections in field hospitals

Soldiers acquired drug-resistant infections in field hospitals
An outbreak of drug-resistant wound infections among soldiers in Iraq likely came from the hospitals where they were treated, not the battlefield, as per a new study in the June 15 issue of Clinical Infectious Diseases, currently available online.

The outbreak of drug-resistant Acinetobacter baumannii-calcoaceticus complex (ABC) infections among U.S. service members injured in Iraq has been of major concern to military health care workers since it was first detected in 2003. ABC bacteria are usually found in soil and water. They sometimes also exist on the skin of healthy people. The bacteria pose little risk to healthy people. However, those with open wounds or weakened immune systems are at greater risk of ABC infection. An ABC infection can cause or contribute to death, particularly if the patient is immunosuppressed.

Historically, ABC infections were treated with a wide variety of drugs. Unfortunately, in recent years, strains of Acinetobacter have been emerging that are resistant to nearly all known remedies. The ABC infections found among the U.S. service members are of this type, known as multi-drug resistant (MDR).

Between March and October 2003, scientists from the Army and the Centers for Disease Control and Prevention identified 145 inpatients at U.S. military therapy facilities infected or colonized with ABC. The scientists attempted to identify the source(s) of the outbreak. They tested for the presence of ABC on the skin of casualties treated in or evacuated from Iraq. They tested soil samples taken near field hospitals in Iraq and from locations throughout Iraq and Kuwait. And they looked at samples taken from in and around patient-treatment areas in five field hospitals in Iraq and two in Kuwait.........

Posted by: Mark      Read more         Source


May 17, 2007, 8:33 PM CT

Genome of yellow fever/dengue fever mosquito sequenced

Genome of yellow fever/dengue fever mosquito sequenced
Developing new strategies to prevent and control yellow fever and dengue fever has become more possible with the completion of the first draft of the genome sequence of Aedes aegypti mosquito by researchers led by Vishvanath Nene at The Institute for Genomic Research (TIGR) and David Severson at the University of Notre Dame. The genome is the complete set of genetic material including genes and other segments of DNA in an organism.

The research appears in the May 18, 2007 Science Express, in the article, "Genome Sequence of Aedes aegypti, A Major Arbovirus Vector." Scientists at 24 universities and other institutions worldwide contributed to the effort.

Among the co-authors are members of the Vector-Borne Infectious Disease Research Group at Virginia Tech (www.vectorborne.ibphs.vt.edu), Zhijian (Jake) Tu, associate professor in the Department of Biochemistry (www.biochem.vt.edu); James K Biedler, biochemistry postdoctoral associate; Song Li, research specialist senior in biochemistry; and Monique Royer Coy, biochemistry graduate student; and Chunhong Mao, senior project associate with the Virginia Bioinformatics Institute at Virginia Tech.

Tu coordinated efforts with TIGR and five research laboratories in the United States, Spain, and France to annotate transposable elements (TEs) in the Ae. aegypti genome. TEs are segments of nucleic acids, or genetic material, that move around the genome and have a significant impact on its structure and size.........

Posted by: Mark      Read more         Source


May 11, 2007, 5:04 PM CT

HIV survival improves if patients stay in care

HIV survival improves if patients stay in care
People with HIV who drop out of care do not live as long as those who remain under a doctor's therapy, said Baylor College of Medicine and Veterans Affairs scientists in a report reported in the June 1 issue of Clinical Infectious Diseases and available on line.

"In an era when highly active treatment directed against HIV (the human immunodeficiency virus that causes AIDS) is keeping people alive, understanding the value of regular medical care is crucial," said Dr. Thomas Giordano, assistant professor of medicine infectious diseases at BCM and lead author of the report.

"We know that adherence to medications is critically important," said Giordano. "Patients who have trouble taking their medicines regularly will do less well. But what about those people who aren't even seeing a doctor regularly" Before this study, we had only a vague understanding of the magnitude of the problem, and we certainly didn't know whether it affected survival".

While HIV is now a chronic or lifelong disease, it is one that typically strikes at a relatively young age. That makes the population different from those who have hypertension or adult-onset diabetes.

"These patients often have a lot of other things going on. They are young. Often, they face challenges of substance abuse, mental health problems and financial issues. Now they have to stay in care the rest of their lives, which may be 20, 30, 40 or more years".........

Posted by: Mark      Read more         Source


April 30, 2007, 8:24 PM CT

Google technology to track avian flu spread

Google technology to track avian flu spread Credit: CU-Boulder, Ohio State University
An interactive "supermap" that portrays the mutations and spread of the avian flu around the globe over time should help scientists and policy makers better understand the virus and anticipate further outbreaks, as per a new study involving University of Colorado at Boulder and Ohio State University researchers.

The research team used data from the known evolution and spread of the avian flu, known as H5N1, to create a roadmap of viral spread in time and space, said CU-Boulder ecology and evolutionary biology Assistant Professor Robert Guralnick, a co-author of study. The team projected genetic and geographic information onto an interactive globe using Google Earth technology, allowing users to fly virtually around the planet and analyze movements and changes in the genomes, or genetic blueprints, of known avian flu sub-strains that have been sequenced since the virus was first detected in Guangdong, China, in 1996.

The scientists used the novel technology to chart the spread of H5N1 through Asia, Indonesia, the Middle East and Europe by various hosts, including its transport by specific orders of birds and mammals, said CU-Boulder graduate student Andrew Hill, a co-author of study. They also used the supermap to track key genetic traits prevalent in some avian flu genomes that appear to confer the ability of H5N1 to more readily infect mammals, including humans, he said.........

Posted by: Mark      Read more         Source


April 30, 2007, 7:07 PM CT

In Case of a Smallpox Outbreak

In Case of a Smallpox Outbreak
In the event of a smallpox outbreak in the United States, how long would it take for a vaccine to start protecting Americans by stimulating an immune response? A new national study led by Saint Louis University School of Medicine will attempt to answer this question.

General routine vaccinations for smallpox were stopped in the United States in 1971, and the world was declared free of smallpox in 1980. But because of the recent concern about biowarfare and bioterrorism throughout the world, the U.S. government is making efforts to improve its ability to protect its citizens in the event of a bioterrorist attack involving the smallpox virus (Variola major virus).

This study at Saint Louis University will look at the ability of an investigational vaccine made by Bavarian Nordic to stimulate the immune system against smallpox.

"Vaccines prevent disease by giving the body a jump-start at recognizing the infecting virus or bacteria," said Sharon Frey, M.D., the principal investigator for the study at Saint Louis University. "After successful vaccination, the body experiences a quicker fighting response to the infection, which lessens or completely avoids the symptoms of illness."

Unlike some other diseases, getting vaccinated following exposure to smallpox could provide protective effects. For example, for the flu vaccine to work, people need to get vaccinated before being exposed to influenza. The currently licensed smallpox vaccine, however, provides benefits post-exposure, and may be useful in further preventing the spread of the disease.........

Posted by: Mark      Read more         Source


April 29, 2007, 7:30 PM CT

Female ticks have market on gluttony

Female ticks have market on gluttony Unfed and engorged tick
Credit: Professor Frans Jongejan, University of Utrecht, Netherlands, and University of Pretoria, Republic of South Africa.
Sex makes you fat. If you're a female tick, that is.

The "truly gluttonous" female ixodid tick increases her weight an astounding 100 times her original size after she mates, so a University of Alberta researcher investigated what it is about copulation that triggers such a massive weight gain.

In a new research paper reported in the Journal of Insect Physiology, Dr. Reuben Kaufman, from the Department of Biological Sciences, suggests several differences between the ixodid tick and her blood-sucking counterparts that help explain the weight gain. Using mosquitoes, tsetse flies, bed bugs and kissing bugs as comparison, Kaufman observed that no one in comparison to this female African tick when it came to weight gain following mating.

Kaufman suggests that the ixodid tick displays a significant difference in lifestyle from the other insects and that it is adaptive for the virgin to remain small before mating.

First, this species of tick remain on the host for many days, rather than minutes. "In this family of ticks, mating takes place on the host," says Kaufman. "Most other insects mate before or after their brief blood meal -the two acts are totally separate, but not with these ticks."

Female ticks require six to 10 days to engorge fully. First, she attaches herself to the skin. Then she feeds to 10 times her unfed weight and finally, after copulation she increases her weight a further tenfold.........

Posted by: Mark      Read more         Source


April 23, 2007, 9:37 PM CT

HIV Survivors Prompts New Treatment Studies

HIV Survivors Prompts New Treatment Studies
A number of patients diagnosed with HIV in the 1980s and 1990s have survived and now are entering their golden years. AIDs cases among the over-50 crowd reached 90,000 in 2003, and as per the Centers for Disease Control and Prevention, will account for half of all HIV/AIDS cases in the United States by 2015.

Consequently, health care providers and social service workers are pioneering new ground to treat the growing number of HIV-positive elderly adults. Timothy Heckman, an Ohio University health psychology expert, has been on the forefront of research involving HIV-infected elderly adults.

Heckman recently received a $1.5 million, four-year grant from the National Institute of Mental Health and the National Institute of Nursing Research to nationally test the effectiveness of a telephone support group for elderly adults with HIV.

Seniors often feel embarrassment or out-of-place among what is commonly a gathering of young people at traditional AIDS support groups. The seniors have different needs, which may not be met, or they may be uncomfortable talking about issues, such as sex, among younger people.

"The telephone, as a tool for delivering support, is financially and psychologically easier for a number of elderly adults," said Heckman, who has spent the past eight years conducting AIDs research among the elderly and in rural populations.........

Posted by: Mark      Read more         Source


April 13, 2007, 5:17 PM CT

How Microbes start immune response

How Microbes start immune response
Immune cells that are the bodys front-line defense dont necessarily rest quietly until invading bacteria lock onto receptors on their outside skins and rouse them to action, as previously thought. In a new paper, University of Michigan researchers describe their findings that bacteria can barge inside these guard cells and independently initiate a powerful immune response.

The study, published online ahead of print in the recent issue of the journal Immunity and accompanied by a special commentary, adds important new details to an emerging picture of how the body recognizes invading bacteria and responds. The work of the U-M team and scientists elsewhere now taking place in laboratory animal studies offers a different way of thinking about how best to design future human vaccines, as well as drugs that could more precisely target the bodys inflammatory response in rheumatoid arthritis and some other autoimmune diseases.

In our study, the presence of bacterial microbes inside the cell is what triggers the immune response. That creates a new perspective for developing new drugs, says senior author Gabriel Nunez, M.D., the Paul H. de Kruif professor of pathology at the U-M Medical School and a member of the U-M Comprehensive Cancer Center.

For years, researchers have believed that when bacteria invade the body, they set off alarms in the immune system by interacting with receptors on a cells surface. But, now new studies are revealing that bacteria can also plunge inside immune system cells and trigger the immune response there. In the new study, Nunez team sheds light on one major pathway in which this process occurs.........

Posted by: Mark      Read more         Source


April 3, 2007, 10:46 PM CT

Rabies-based Vaccine Against Hiv

Rabies-based Vaccine Against Hiv
Rabies, a relentless, ancient scourge, may hold a key to defeating another implacable foe: HIV. Researchers at Jefferson Medical College in Philadelphia have used a drastically weakened rabies virus to ferry HIV-related proteins into animals, in essence, vaccinating them against an AIDS-like disease. The early evidence shows that the vaccine which doesnt protect against infection prevents development of disease.

Reporting April 1, 2007 in the Journal of Infectious Diseases, the researchers showed that two years after the initial vaccination, four vaccinated non-human primates were protected from disease, even after being "challenged" with a dangerous animal-human virus. Two control animals developed an AIDS-like disease.

Matthias Schnell, Ph.D., professor of microbiology and immunology at Jefferson Medical College of Thomas Jefferson University, and his co-workers tested the effects of inserting two different viral proteins into the rabies virus genome, and using such viruses-based vaccines in preventing disease in rhesus macaques. One was a glycoprotein on the surface of HIV, while the other was an internal protein from simian immunodeficiency virus (SIV). They used the latter because HIV does not cause disease in monkeys.

The idea was that such rabies vehicles, or "vectors," would help attract a strong response from the animals immune system, though the rabies virus used cannot cause disease. Such vectors are based on a type of rabies vaccine strain that has been used for more than 20 years in oral vaccines against rabies in wildlife in Europe. The study was aimed at studying the safety and effectiveness of the rabies vaccine approach against HIV and related diseases.........

Posted by: Mark      Read more         Source



Older Blog Entries   1   2   3   4   5   6   7   8   9   10   11   12   13   14   15   16   17   18   19   20   21  

Did you know?
Scientists at Baylor College of Medicine in Houston have found a genetic marker that may identify individuals at greater risk for life-threatening infection from the West Nile virus. Results of the study are reported in the Nov. 15 print edition of Journal of Infectious Diseases.

Medicineworld.org: Archives of infectious disease blog

SARS Main| SARS Abroad| SARS and Goverment| SARS Information in different languages| Media about SARS| Physicians resources for SARS| Reference information for SARS| Updates on SARS|

Copyright statement
The contents of this web page are protected. Legal action may follow for reproduction of materials without permission.