Resistance

Study identifies predictors of HIV drug resistance in patients beginning triple therapy

A scientist at the Marine BiologicalLaboratory (MBL) has published the results of an EPA-funded clam embryostudy that supports her hypothesis that, when combined, the pollutantsbromoform, chloroform, and tetrachloroethylene--a chemical cocktailknown as BCE--can act synergistically to alter a key regulator in nervecell development. While scientists have previously studied the effectsof these...

Researchers make gains in understanding antibiotic resistance

Howard Hughes Medical Institute researchers chiseling away at the problem of antibiotic resistance now have a detailed explanation of how the drugs' main cellular target in bacteria evolves to become resistant to some of these medications. The findings are already leading to new experimental antibiotics that are being engineered to circumvent resistance, which is a major worldwide health problem....

MUHC scientists describe genetic resistance to rampant virus

MUHC researchers have defined genetic resistance to the widespread virus, cytomegalovirus (CMV)--a member of the viral group that causes some of the world's most prevalent diseases, such as herpes, chicken pox and mononucleosis. The groundbreaking research published in Nature Genetics last week, provides a roadmap for the development of human therapies for CMV, which could prolong the life of HIV...

New polysaccharide may help combat multidrug resistance in cancer

In a recent study published in the Journal of Biological Chemistry, scientists report that a molecule previously thought to play a purely structural and inert role in cells is actually involved in multidrug resistance in cancer. Using antagonists for this molecule, the researchers were able to sensitize drug resistant breast cancer cells to chemotherapeutic drug treatment. The research ap...

To Stop Evolution: New Way Of Fighting Antibiotic Resistance Demonstrated By Scripps Scientists

A team of scientists at The Scripps Research Institute and the University of Wisconsin have demonstrated a new way of fighting antibiotic resistance: by stopping evolution. In the June issue of the open-access journal PloS Biology, the team describes how a protein called LexA in the bacterium Escherichia coli promotes mutations and helps the pathogen evolve resistance to antibiotics. The...

New book explains antibiotic resistance for a broad audience

Media coverage about "superbugs" that defy current treatments has increased the public's awareness of and fears surrounding the issue of antibiotic resistance. A new book from ASM Press, Revenge of the Microbes: How Bacterial Resistance is Undermining the Antibiotic Miracle, provides an in-depth overview of the subject in a reader-friendly, comprehensible style that will engage everyone from scie...

Insects develop resistance to engineered crops

Genetically modified crops containing two insecticidal proteins in a single plant efficiently kill insects. But when crops engineered with just one of those toxins grow nearby, insects may more rapidly develop resistance to all the insect-killing plants, report Cornell University researchers. A soil bacterium called Bacillus thuringiensis (Bt), whose genes are inserted into crop plants, su...

Retroviral resistance gene found

Dr. Stephen Goff and colleagues have identified a novel retroviral resistance gene, called FEZ1, that can mediate a potent resistance to murine leukemia virus, as well as HIV-1, in cell culture. The researchers found that the high level of FEZ1 expression in a specific laboratory rat cell line caused a significant block to retroviral infection ?retroviruses were able to enter the host cells and s...

Drug resistance testing in treatment-naive HIV patients is cost-effective

Testing for drug resistance in HIV-infected patients at the time of HIV diagnosis is cost-effective and may increase patients' life expectancy, according to an article in the Nov. 1 issue of Clinical Infectious Diseases, now available online. Resistance to antiretroviral therapy, even in patients who have never received treatment, is a growing concern. However, genotype resistance testing...

Researchers use RNAi libraries to identify regulators of apoptosis and chemoresistance

When it comes to the deadly skin cancer melanoma, studying functional tissue rather than cell lines may better provide insight into the disease's development, according to new research from a Howard Hughes Medical Institute predoctoral fellow at Stanford University School of Medicine. Though multiple genetic alterations are associated with melanoma development, scientists have not been abl...

Large-scale Computer Simulations Reveal New Insights Into Antibiotic Resistance

Novel use of genetic testing methods helped public health officials control and limit the further spread of four outbreaks of foodborne hepatitis A virus in 2003 related to the consumption of green onions, according to a detailed analysis published in the October 15 issue of The Journal of Infectious Diseases, now available online. The authors of the study, Joseph J. Amon, PhD, MSPH, and c...

Gaining ground in the race against antibiotic resistance

Antibiotic resistance has put humans in an escalating 'arms race' with infectious bacteria, as scientists try to develop new antibiotics faster than the bacteria can evolve new resistance strategies. But now, researchers have a new strategy that may give them a leg up in the race -- reproducing in the lab the natural evolution of the bacterial enzymes that confer resistance. A team of sci...

Genes linked to treatment resistance in children with leukemia

Today, the most common childhood cancer is cured in about 80 percent of patients; only forty years ago, this number was closer to five percent. In efforts to further increase the survival rate, researchers from St. Jude Children's Research Hospital, the University of Tennessee, and the University of Chicago studied how an individual's genetics might play a role in the effectiveness of chemotherap...

Einstein researchers identify new way that bacteria develop resistance to antibiotics

Scientists at the Albert Einstein College of Medicine have discovered a novel strategy by which the bacterium that causes tuberculosis may soon be able to resist the effects of antibiotics known as fluoroquinolones. The finding explains why several disease-causing microbes, including Shigella and E. coli, are rapidly becoming resistant to fluoroquinolones. The international research effort...

DDT-resistant insects have additional genetic advantage that helps resistance spread

Insects that can withstand the powerful pesticide DDT that was banned in the 1970s have an additional genetic advantage over their rivals that has helped them spread across the globe ever since, according to research published in Current Biology tomorrow (9 August 2005). This discovery overturns current theories that resistance to pesticides burdens insects with a genetic disadvantage tha...

HIV drug resistance increasing in UK and among highest in the world

Those infected with HIV in the UK have one of the highest rates of resistance to anti-HIV drugs of anywhere in the world, prompting fears of a second wave epidemic of resistant virus, a new study claims in this week's BMJ. The study authors are concerned that the large reductions in deaths and improvements to health since people with HIV were given combinations of drugs (combination antire...

Pretreating rogue cancer cells with aspirin cripples their resistance to targeted therapy

Safeguarding 595 sites around the world would help stave off an imminent global extinction crisis, according to new research published today in the Proceedings of the National Academy of Sciences ( Conducted by scientists working with the 52 member organizations of the Alliance for Zero Extinction (AZE –?<A HREF="http://www.zeroextinction.org...

Pair of studies offer new clues to combat antibiotic resistance

In the continuing battle against antibiotic resistance, two new studies shed light on the complex defense mechanisms pathogenic bacteria use to evade antibiotic attack, an understanding of which could lead to new, more effective antibiotics to help save lives and combat the growing problem of antibiotic resistance. The studies, both of which target chemical components in the protective membrane s...

Researchers use dirt to stay one step ahead of antibiotic resistance

Dirt may be a key to how bacteria that infect humans develop a resistance to antibiotic drugs. In an article in the January 20 issue of the journal Science, McMaster University researchers say that study of bacteria found in dirt may be the key in identifying how and why antibiotic resistance happens in bacteria that infect people, predicting future clinical problems, and testing new antib...

Lack of a key enzyme dramatically increases resistance to sepsis

According to the new study, the presence of caspase-12, which appears to modulate inflammation and innate immunity in humans, increases the body's "vulnerability to bacterial infection and septic shock" while a deficiency confers strong resistance to sepsis. This new discovery suggests that caspase-12 antagonists could be a potentially useful in the treatment of sepsis and other inflammatory and...

Less antibiotic use in food animals leads to less drug resistance in people, study shows

Australia's policy of restricting antibiotic use in food-producing animals may be linked with lower levels of drug-resistant bacteria found in its citizens, according to an article in the May 15 issue of Clinical Infectious Diseases, now available online. Campylobacter jejuni is a leading bacterial cause of foodborne illness in industrialized countries. Drug resistance can make Campylobac...

Supersized 'island' of resistance genes discovered in an infectious bacterium

Researchers have discovered a cluster of 45 genes coding for antibacterial drug resistance in the bacterium, Acinetobacter baumannii, a major cause of hospital-acquired infections worldwide. The study was reported in the open-access journal PLoS Genetics. "We expected to find resistance genes," said lead author, Pierre-Edouard Fournier, researcher at the Structural and Genomic Information...

Scientists re-engineer a well-known antibiotic to counter drug resistance

The scientists replaced a single atom from the molecular structure of vancomycin aglycon, a glycopeptide antibiotic that attacks the bacteria by inhibiting cell wall synthesis, significantly increasing the drug's spectrum of activity. In recent years, a number of the most common strains of enterococci have become resistant to vancomycin and use of the antibiotic has been under scrutiny. This re-e...

Macrophage signaling may affect hormone resistance in prostate tumors

Interaction between prostate cancer cells and immune cells called macrophages may be a source of inflammatory signals capable of impacting the effectiveness of androgen antagonists, the most common and effective treatment for prostate cancer, according to a new study by researchers at the University of California, San Diego (UCSD) School of Medicine. Male hormones called androgens are es...

Viral 'fitness' explains different resistance patterns to aids drugs

Some HIV medications lead to the development of drug-resistant HIV when patients take as few as two percent of their medications. For other medications, resistance occurs only when patients take most of their pills. These differences appear to be explained by the different levels of viral "fitness" of the drug-resistant HIV, say AIDS researchers in a new study. The research, led by David B...

Drug resistance may travel same path as quorum sensing

The cellular "pumps" associated with multi-drug resistance in bacteria may also be involved in exporting signals responsible for cell-cell communication, a process known as quorum sensing, said researchers from Baylor College of Medicine in a report that appears online today in the Proceedings of the National Academy of Sciences. "We believe that the drugs exported by these pumps may actua...

Evolution follows few of the possible paths to antibiotic resistance

Darwinian evolution follows very few of the available mutational pathways to attain fitter proteins, researchers at Harvard University have found in a study of a gene whose mutant form increases bacterial resistance to a widely prescribed antibiotic by a factor of roughly 100,000. Their work indicates that of 120 harrowing, five-step mutational paths that theoretically could grant antibiotic resi...

Genetically engineered mosquitoes show resistance to dengue fever virus

Researchers have successfully created a genetically engineered mosquito that shows a high level of resistance against the most prevalent type of dengue fever virus, providing a powerful weapon against a disease that infects 50 million people each year. Anthony James, a UC Irvine vector biologist, is one of a team of researchers who injected DNA into mosquito embryos, creating the first sta...

Innocuous intestinal bacteria may be reservoir for resistance

"Harmless" bacteria in the digestive tracts of dairy cows, may not be so harmless after all. They may be a reservoir for antibiotic resistance genes that can be transferred to more harmful, disease-causing bacteria, according to research presented today at the 106th General Meeting of the American Society for Microbiology in Orlando, Florida. "There is concern that veterinary therapeutic...

Over-use of antibiotics in fish-for-food industry encourages bacterial resistance and disease

The heavy use of antibiotics in the rearing of fish could be detrimental to the health of the fish, but also that of animals and humans, a recent report says. This practice encourages bacterial resistance and could lead to the evolution of resistant strains of bacteria in animals and humans as well as the fish themselves. A more judicious approach to the use of prophylactic (preventative) antibio...

Pak1 expression increases tamoxifen resistance in breast cancer patients

A protein that activates estrogen receptors in breast cancer may play a role in resistance to therapeutic effects of anti-estrogen tamoxifen treatment, according to a study in the May 17 Pak 1 is a member of a family of proteins involved in many cell functions, such as gene expression, cell movement, and cell death. Previous studies have...

New bird flu drug promises to beat the problem of resistance

A new kind of drug to fight bird flu that will not suffer from the same kind of resistance problems as current treatments should begin clinical trials within the next three years, thanks to a new research grant. Dr Andrew Watts from the University of Bath (UK) and Dr Jennifer McKimm-Breschkin from CSIRO (Australia) have been awarded over £408,000 from the Medical Research Council (MRC) to...

UGA scientists engineer root-knot nematode resistance

University of Georgia professor Richard Hussey has spent 20 years studying a worm-shaped parasite too small to see without a microscope. His discovery is vastly bigger. Hussey and his research team have found a way to halt the damage caused by one of the world's most destructive groups of plant pathogens. Root-knot nematodes are the most economically important group of plant-parasitic nema...

Cancer stem cells linked to radiation resistance

Certain types of brain cancer cells, called cancer stem cells, help brain tumors to buffer themselves against radiation treatment by activating a "repair switch" that enables them to continue to grow unchecked, researchers at Duke University Medical Center have found. The researchers also identified a method that appears to block the cells' ability to activate the repair switch following r...

Resistance and genetic sensitivity to sleeping sickness

Human African trypanosomiasis, more commonly called sleeping sickness, is induced by a parasite, the trypanosome, transmitted to humans by the bite of an insect, the glossinid tse-tse fly. There has been a resurgence of this disease over the past 20 years in Sub-Saharan Africa. The World Health Organization (WHO) in a 1998 report estimated the number of people infected to be about 300 000. Awaren...

Key to lung cancer chemo resistance revealed

Scientists at Johns Hopkins have discovered how taking the brakes off a "detox" gene causes chemotherapy resistance in a common form of lung cancer. Products made by a gene called NRF2 normally protect cells from environmental pollutants like cigarette smoke and diesel exhaust by absorbing the materials and pumping them out of the cell. Another gene called KEAP1 encodes products that sto...

Controlling antibiotics and antibiotic resistance in hospitals

In one of the first national studies on guidelines that control antibiotics and antibiotic resistance in hospitals, researchers from the Indiana University School of Medicine, the Regenstrief Institute, Inc. and the Richard Roudebush Veterans Administration Medical Center report that hospitals that follow national guidelines on controlling antibiotic use have lower rates of antibiotic resistance....

Elusive rust resistance genes located

The discovery of a DNA marker for two key rust resistance genes is enabling plant breeders around the world to breed more effective rust resistant wheat varieties. CSIRO Plant Industry scien...

'Failed' experiment yields a biocontrol agent that doesn't trigger antibiotic resistance

MADISON - A failed experiment turned out to be anything but for bacteriologist Marcin Filutowicz. The discovery also led to the startu...

Discovery of the first resistance gene to rice yellow mottle virus

Rice yellow mottle virus (RYMV) was first identified in 1966 in Kenya. It has since been reported in most African countries where rice is grown. The disease is characterized by the appearance of mottling and then tissue death on the leaves. The fertility and development of seeds are affected, which causes considerable yield losses at harvest. Transmission of RYMV occurs by way of insect v...