Tag Archives: medical research

MIT Scientists Find New Drug That Could Cure Nearly Any Viral Infection

New drug could cure nearly any viral infection

The drug works by targeting a type of RNA produced only in cells that have been infected by viruses. “In theory, it should work against all viruses,” says Todd Rider, a senior staff scientist in Lincoln Laboratory‘s Chemical, Biological, and Nanoscale Technologies Group who invented the new technology.

There are a handful of drugs that combat specific viruses, such as the protease inhibitors used to control HIV infection, but these are relatively few in number and susceptible to viral resistance.

Rider drew inspiration for his therapeutic agents, dubbed DRACOs (Double-stranded RNA Activated Caspase Oligomerizers), from living cells’ own defense systems. When viruses infect a cell, they take over its cellular machinery for their own purpose — that is, creating more copies of the virus. During this process, the viruses create long strings of double-stranded RNA (dsRNA), which is not found in human or other animal cells.

As part of their natural defenses against viral infection, human cells have proteins that latch onto dsRNA, setting off a cascade of reactions that prevents the virus from replicating itself. However, many viruses can outsmart that system by blocking one of the steps further down the cascade.

Rider had the idea to combine a dsRNA-binding protein with another protein that induces cells to undergo apoptosis (programmed cell suicide) — launched, for example, when a cell determines it is en route to becoming cancerous. Therefore, when one end of the DRACO binds to dsRNA, it signals the other end of the DRACO to initiate cell suicide.

Combining those two elements is a “great idea” and a very novel approach, says Karla Kirkegaard, professor of microbiology and immunology at Stanford University. “Viruses are pretty good at developing resistance to things we try against them, but in this case, it’s hard to think of a simple path pathway to drug resistance,” she says.

Each DRACO also includes a “delivery tag,” taken from naturally occurring proteins, that allows it to cross cell membranes and enter any human or animal cell. However, if no dsRNA is present, DRACO leaves the cell unharmed.

Very cool stuff and potentially hugely beneficial. Just a reminder: this works against viruses – not bacteria (just as antibiotics do not work against viruses).

image showing the results of cultures treated with DRACO v. those not treated

Related: Science Explained: RNA Interference8 Percent of the Human Genome is Old Virus GenesVirus Engineered To Kill Deadly Brain Tumors
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Cat Allergy Vaccine Created

McMaster University researchers have developed a vaccine which successfully treats people with an allergy to cats. Traditionally, frequent allergy shots have been considered the most effective way to bring relief — other than getting rid of the family pet — for the 8 to 10% of the population allergic to cats.

Both options, may now be avoided thanks to the work of immunologist Mark Larché, professor at the Michael G. DeGroote School of Medicine and Canada Research Chair in Allergy & Immune Tolerance.

Building on research he’s conducted for the past 10 years in Canada and Britain, Larché and his research team have developed a vaccine which is effective and safe with almost no side effects. The research is published in a the January 2011 issue of the Journal of Allergy & Clinical Immunology, a leading journal in the allergy field.

The researchers took one protein (molecule) that cats secrete on their fur which causes the majority of allergic problems. Using blood samples from 100 patient volunteers allergic to cats, they deconstructed the molecule and identified short regions within the protein which activate T-cells (helper cells that fight infection) in the immune system.

Using the amino acid code for the whole protein, researchers made synthetic versions of these regions. For the cat allergy vaccine, they found seven peptides (strings of amino acids). “And those synthetic peptides are what we mix together to make the vaccine,” said Larché. “We picked the peptides that would work in as much of the population as possible.”

Known as “peptide immunotherapy,” a low dose of the vaccine is given into the skin. Initially, four to eight doses a year may be required, but the side effects of the traditional allergy shots do not arise, Larché said. The optimal dose will be determined in phase three clinical trials which are getting underway with a much larger group of cat allergy sufferers.

The development of a vaccine to treat people allergic to cats is the first in a line of vaccines developed with Adiga Life Sciences, a company established at McMaster in 2008. It is a joint venture between McMaster University Circassia Ltd., a UK-based biotech company.

Adiga and McMaster are now collaborating on research into the use of peptide immunotherapy for house dust mite, ragweed, grass, birch tree and moulds

Related: MIT Engineers Design New Type of Nanoparticle for Vacines10 Questions to Ask Your Vet About Cat MedicationsVaccine For Strep Infections

Video showing malaria breaking into cell

Malaria caught on camera breaking and entering cell [the broken link has been removed]

The Plasmodium parasite responsible for malaria is transmitted by the bite of infected mosquitoes, and is thought to kill almost 1 million people worldwide each year.

Jake Baum at the Walter and Eliza Hall Institute of Medical Research in Melbourne, Australia, and colleagues used transmission electron microscopy and 3D immuno-fluorescence microscopy to record a series of still images during the 30-second-long invasion, and combined them into a movie.

Related: Parasites in the Gut Help Develop a Healthy Immune SystemParasite Rex

Aerobic Exercise Plus Resistance Training Helps Control Type 2 Diabetes

Exercise Combo Best for Controlling Diabetes

A combination of aerobic exercise and resistance training may offer the biggest benefits for people with type 2 diabetes in helping them control their disease.

HbA1c is a test that measures blood sugar control for the previous few months. Normal HbA1c is 6% or less. People with diabetes are urged to keep their HbA1c below 7%.

In the study, researchers compared the effects of a nine-month aerobic exercise program, a resistance training program, and combination exercise program vs. not exercising in 262 previously sedentary men and women with type 2 diabetes. The results showed that improvements in HbA1c levels were greatest among those who were in the combination group.

Thirty-nine percent of non-exercisers had to increase these medications compared with 32% in the resistance training group, 22% in the aerobic exercise group, and 18% in the combination group.

Diabetes is a huge and growing problem. Exercise is a good strategy to remain healthy. It is best to exercise and avoid becoming sick. But if you do get diabetes then it is even more important to take care to exercise properly.

Related: Surprising New Diabetes DataDiabetes up 90% in USA since 1997 – Study Finds Obesity as Teen as Deadly as Smoking

Are you ready for a world without antibiotics?

Are you ready for a world without antibiotics?

[Professor Tim Walsh] “This is potentially the end. There are no antibiotics in the pipeline that have activity against NDM 1-producing enterobacteriaceae. We have a bleak window of maybe 10 years, where we are going to have to use the antibiotics we have very wisely, but also grapple with the reality that we have nothing to treat these infections with.”

And this is the optimistic view – based on the assumption that drug companies can and will get moving on discovering new antibiotics to throw at the bacterial enemy. Since the 1990s, when pharma found itself twisting and turning down blind alleys, it has not shown a great deal of enthusiasm for difficult antibiotic research. And besides, because, unlike with heart medicines, people take the drugs for a week rather than life, and because resistance means the drugs become useless after a while, there is just not much money in it.

“The emergence of antibiotic resistance is the most eloquent example of Darwin’s principle of evolution that there ever was,” says Livermore. “It is a war of attrition. It is naive to think we can win.”

I have been writing about the huge risks we are talking with our future for years. The careless misuse of antibiotics is very costly (in human lives, in the future). Bacteria pose great risks to us. We need to take antibiotics to fight serious threats. The misuse of antibiotics by doctors, patients, agri-business… is the problem. And we are all living a much riskier future because far to little is being done to reduce the misuse of antibiotics.

More and more antibiotic treatments are losing effectiveness as bacteria evolve resistance. The evolution is accelerated by misuse. This costs lives today, but is likely to costs many thousands and hundreds of thousands and possible more in the next 50 years.

The NDM-1-producing bacteria were highly resistant to all antibiotics except tigecycline and colistin. In some cases, isolates were resistant to all antibiotics. The emergence of NDM-1 positive bacteria is potentially a serious global public health problem as there are few new anti-Gram-negative antibiotics in development and none that are effective against NDM-1.

Related: Antibiotics Breed Superbugs Faster Than ExpectedAntibiotics Too Often Prescribed for Sinus WoesBacteria Race Ahead of DrugsFDA May Make Decision That Will Speed Antibiotic Drug ResistanceRaised Without AntibioticsWaste Treatment Plants Result in Super BacteriaHow Bleach Kills BacteriaCDC Urges Increased Effort to Reduce Drug-Resistant Infections

Students Will Spend Year Doing Career-Changing Research Thanks to HHMI

This year, 116 medical, dental, and veterinary students from 47 schools across the country will take a break from memorizing molecular metabolism and studying drug interactions to spend a year in a lab doing hands-on research. The break from regular coursework, funded through a $4 million Howard Hughes Medical Institute (HHMI) initiative, is intended to give students an opportunity to immerse themselves in science and consider whether they want to pursue a career as a physician-scientist.

Nearly 500 medical students applied for the research year through the HHMI-National Institutes of Health (NIH) Medical Research Scholars and HHMI Medical Research Fellows programs. Both efforts seek to strengthen and expand the pool of medically-trained researchers. The funding HHMI provides is a great resource.

“We want medical, dental, and veterinary students to become immersed in the life of academic science for at least a year. And we hope they get so engaged in the process and life of scientific research that they will decide to continue it for the rest of their lives,” says Peter Bruns, HHMI’s vice president for grants and special programs. “We need more doctors who do basic research to improve human health.”

As part of its commitment to fostering the translation of basic research discoveries into improved diagnoses and treatments, HHMI has developed a range of programs to nurture the careers of researchers who bridge the gap between clinical medicine and basic science. In addition to the programs for medical students, the Institute supports medical training for Ph.D. students in the basic sciences and has made specific efforts to fund top physician-scientists as HHMI investigators.

The medical research scholars and fellows programs are open to medical, dental, and veterinary students enrolled in U.S. schools. Most have completed the second or third year of their professional program when they spend a year working in a lab either at the NIH or at an academic medical center or research university they select. During the last 25 years, more than 2,100 students have participated.

The HHMI Medical Research Fellowships program allows medical, dental, and veterinary students to pursue biomedical research at a laboratory anywhere in the United States except the NIH campus in Bethesda. Each student submits a research plan to work in a specific lab with a mentor they have identified. Since 1989, about 1,200 students have participated.

This year, 74 students from 26 medical schools and two veterinary schools were chosen as fellows from a pool of 274. While most students elect to stay at their home institution to do their research, this year 17 fellows will work in labs at a different school. Their research topics include schizophrenia, wound healing, organ development, and many other important biological questions.

The HHMI-NIH Research Scholars program was established in 1985 to encourage medical students to pursue research by allowing them to take a year off from their medical studies. The program has since been expanded to include dental and veterinary students. It has enabled about 1,000 students to work in NIH labs.

Students selected as research scholars often enter the program with only a general idea of what type of research they would like to do. As soon as they are accepted, they begin researching the more than 1,100 laboratories at NIH. They meet with a number potential mentors before finalizing which project to pursue under the guidance of their NIH advisor and HHMI’s staff. The students are sometimes called “cloister scholars” because they live in apartments or dorm-style rooms in a refurbished cloister on the NIH campus in Bethesda.

This year, 42 students from 28 medical schools and one veterinary school were chosen as research scholars. More than 200 students from 93 schools applied.

Related: Directory of Science and Engineering Scholarships and Fellowships$600 Million for Basic Biomedical ResearchHHMI Expands Support of Postdoctoral ScientistsGenomics Course For College Freshman Supported by HHMI at 12 Universities

A Breakthrough Cure for Ebola

A breakthrough cure for Ebola By Steven Salzberg

Last week, in what may be the biggest medical breakthrough of its kind in years, a group of scientists published results in The Lancet describing a completely new type of anti-viral treatment that appears to cure Ebola. They report a 100% success rate, although admittedly the test group was very small, just 4 rhesus monkeys.

This is a breakthrough not only because it may give us a cure for an uncurable, incredibly nasty virus, but also because the same method might work for other viruses, and because we have woefully few effective antiviral treatments. We can treat bacterial infections with antibiotics, but for most viruses, we have either a vaccine or nothing. And a vaccine, wonderful as it is, doesn’t help you after you’re already infected.

The scientists, led by Thomas Geisbert at Boston University, used a relatively new genomics technique called RNA interference to defeat the virus. Here’s how it works.
First, a little background: the Ebola virus is made of RNA, just like the influenza virus. And just like influenza, Ebola has very few genes – only 8. One of its genes, called L protein, is responsible for copying the virus itself. Two others, called VP24 and VP35, interfere with the human immune response, making it difficult for our immune system to defeat the virus.

Geisbert and his colleagues (including scientists from Tekmira Pharmaceuticals and USAMRIID) designed and synthesized RNA sequences that would stick to these 3 genes like glue. How did they do that? We know the Ebola genome’s sequence – it was sequenced way back in 1993. And we know that RNA sticks to itself using the same rules that DNA uses. This knowledge allowed Geisbert and colleagues to design a total of 10 pieces of RNA (called “small interfering RNA” or siRNA) that they knew would stick to the 3 Ebola genes. They also took care to make sure that their sticky RNA would not stick to any human genes, which might be harmful. They packaged these RNAs for delivery by inserting them into nanoparticles that were only 81-85 nanometers across.

Related: Science Explained: RNA InterferenceAmazing Science: RetrovirusesEbola Outbreak in Uganda (Dec 2007)

Evidence that Refined Carbohydrates Threaten the Heart

More Evidence that Refined Carbohydrates, not Fats, Threaten the Heart

Eat less saturated fat: that has been the take-home message from the U.S. government for the past 30 years. But while Americans have dutifully reduced the percentage of daily calories from saturated fat since 1970, the obesity rate during that time has more than doubled, diabetes has tripled, and heart disease is still the country’s biggest killer. Now a spate of new research, including a meta-analysis of nearly two dozen studies, suggests a reason why: investigators may have picked the wrong culprit. Processed carbohydrates, which many Americans eat today in place of fat, may increase the risk of obesity, diabetes and heart disease more than fat does – a finding that has serious implications for new dietary guidelines expected this year.

Right now, Post explains, the agency’s main message to Americans is to limit overall calorie intake, irrespective of the source. “We’re finding that messages to consumers need to be short and simple and to the point,” he says. Another issue facing regulatory agencies, notes Harvard’s Stampfer, is that “the sugared beverage industry is lobbying very hard and trying to cast doubt on all these studies.”

The medical studies about what food to eat to remain healthy can be confusing but some details are not really in doubt. So while the exact dangers of processed carbohydrates, fat, excess calories and high fructose corn syrup may be in question their is no doubt we, in the USA, are not as healthy as we should be. And food is a significant part of the problem. Eat food, not too much, mostly plants and get enough exercise is good advice.

Related: Statistical Errors in Medical StudiesResearchers Find High-Fructose Corn Syrup Results in More Weight GainThe Calorie DelusionObesity Epidemic Explained, Kind OfActive Amish Avoid Obesity

Non-infectious Prion Protein Linked to Alzheimer’s Disease

‘Harmless’ prion protein linked to Alzheimer’s disease

Non-infectious prion proteins found in the brain may contribute to Alzheimer’s disease, researchers have found.

normal prion proteins produced naturally in the brain interact with the amyloid-β peptides that are hallmarks of Alzheimer’s disease. Blocking this interaction in preparations made from mouse brains halted some neurological defects caused by the accumulation of amyloid-β peptide. It was previously thought that only infectious prion proteins, rather than their normal, non-infectious counterparts, played a role in brain degeneration.

Alzheimer’s disease has long been linked to the build-up of amyloid-β peptides, first into relatively short chains known as oligomers, and then eventually into the long, sticky fibrils that form plaques in the brain. The oligomeric form of the peptide is thought to be toxic, but exactly how it acts in the brain is unknown.

Related: Soil Mineral Degrades the Nearly Indestructible PrionPrion Proteins, Without Genes, Can EvolveClues to Prion Infectivity

Researchers Find High-Fructose Corn Syrup Results in More Weight Gain

A Princeton University research team has demonstrated that rats with access to high-fructose corn syrup gained significantly more weight than those with access to table sugar, even when their overall caloric intake was the same. In addition to causing significant weight gain in lab animals, long-term consumption of high-fructose corn syrup also led to abnormal increases in body fat, especially in the abdomen, and a rise in circulating blood fats called triglycerides

Photo of Princeton University research team, including (from left) undergraduate Elyse Powell, psychology professor Bart Hoebel, visiting research associate Nicole Avena and graduate student Miriam Bocarsly, by Denise Applewhite

Photo of Princeton University research team, including (from left) undergraduate Elyse Powell, psychology professor Bart Hoebel, visiting research associate Nicole Avena and graduate student Miriam Bocarsly, by Denise Applewhite

The first study showed that male rats given water sweetened with high-fructose corn syrup in addition to a standard diet of rat chow gained much more weight than male rats that received water sweetened with table sugar, or sucrose, in conjunction with the standard diet. The concentration of sugar in the sucrose solution was the same as is found in some commercial soft drinks, while the high-fructose corn syrup solution was half as concentrated as most sodas.

The second experiment — the first long-term study of the effects of high-fructose corn syrup consumption on obesity in lab animals — monitored weight gain, body fat and triglyceride levels in rats with access to high-fructose corn syrup over a period of six months. Compared to animals eating only rat chow, rats on a diet rich in high-fructose corn syrup showed characteristic signs of a dangerous condition known in humans as the metabolic syndrome, including abnormal weight gain, significant increases in circulating triglycerides and augmented fat deposition, especially visceral fat around the belly. Male rats in particular ballooned in size: Animals with access to high-fructose corn syrup gained 48 percent more weight than those eating a normal diet. In humans, this would be equivalent to a 200-pound man gaining 96 pounds.

“These rats aren’t just getting fat; they’re demonstrating characteristics of obesity, including substantial increases in abdominal fat and circulating triglycerides,” said Princeton graduate student Miriam Bocarsly. “In humans, these same characteristics are known risk factors for high blood pressure, coronary artery disease, cancer and diabetes.” In addition to Hoebel and Bocarsly, the research team included Princeton undergraduate Elyse Powell and visiting research associate Nicole Avena, who was affiliated with Rockefeller University during the study and is now on the faculty at the University of Florida. The Princeton researchers note that they do not know yet why high-fructose corn syrup fed to rats in their study generated more triglycerides, and more body fat that resulted in obesity.

Related: High Fructose Corn Syrup is Not Natural Food says the FDAWaste from Gut Bacteria Helps Host Control WeightAnother Strike Against ColaThe Calorie Delusion
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