News 3 november 2009
2-pronged protein attack could be
source of SARS virulence
Ever since the previously unknown SARS virus emerged from southern China in 2003,
University of Texas Medical Branch at Galveston virologists have focused on finding the
source of the pathogen's virulence — its ability to cause disease. In the 2003
epidemic, for example, between 5 and 10 percent of those who fell sick from the SARS virus
died, adding up to more than 900 fatalities worldwide. Now, UTMB researchers have
uncovered what they believe could be the major factor contributing to the SARS virus'
virulence: the pathogen's use of a single viral protein to weaken host cell defenses by
launching a "two-pronged" attack on cellular protein-synthesis machinery. Their
results show that copies of this viral protein, known as nsp1, directly interferes with
the tiny cellular machines called ribosomes, which make the proteins, such as interferon
beta, that are crucial for immune defense. (If the word "ribosome" sounds
familiar, it's probably because the three scientists who first determined what the
miniature protein factories look like and how they function won the 2009 Nobel Prize for
Chemistry.) Nsp1 is also involved in degrading the biochemical messages that are decoded
by these ribosomes to produce such proteins. "This SARS virus protein, nsp1, binds to
ribosomes to inactivate them and also modifies messenger RNA molecules to make them
unreadable," said UTMB professor Shinji Makino, senior author of a paper on the
discovery appearing in the online edition of Nature Structure and Molecular Biology.
"We think that this property of nsp1 could be a major player in the virulence of
SARS."
Link
A researcher at the Technical
University of Catalonia (UPC) designs the first ever synthetic gene circuit that works
like that of a natural cell
The experiment, featured on the cover of the leading weekly science journal Cell of
October 30, shows that cells use chance to survive uncertainty. “God does not play
dice,” said Einstein to explain that chance does not intervene in nature. However,
researcher Jordi García Ojalvo, from the Campus of the UPC in Terrassa, has carried out
an experiment, featured on the cover of the leading weekly international journal Cell of
October 30 that shows that this is not the case for living organisms. The experiment is
the first to succeed in creating a synthetic gene circuit that functions in the same
manner as a natural live stem cell. Why do living beings choose to function a certain way?
Why do cells base their operation on certain gene circuits and not others? These questions
are among the central issues of contemporary science; we need to know the answers in order
to understand how living beings work and how cell imbalances cause all kinds of diseases,
from cancer to autoimmune diseases. Researcher Jordi García Ojalvo, from the Campus of
the UPC in Terrassa, has faced these issues by designing the first ever synthetic gene
circuit that works in the same way as an in vivo natural circuit, and he has compared the
two.
Link
B-vitamins may offer relief from
migraines
Supplements of vitamins B-6 and B-12 and folic acid may reduce the frequency, severity and
disability of migraines, according to new research from Australia.
Link
Big protein portions don’t
mean more muscle
UTMB’s Douglas Paddon-Jones was interviewed about a study that he and colleagues
conducted that found only the first 30 grams of protein in a meal, the amount in four
ounces of lean beef, chicken, soy or dairy, is turned into muscle.
Link
Broccoli Sprouts May Cut Stomach
Ulcer Risk
Daily consumption of broccoli sprouts may cut Helicobacter pylori (H. pylori) infections
and offer protection against stomach ulcers.
Link
Caltech researchers show efficacy
of gene therapy in mouse models of Huntington's disease
Researchers at the California Institute of Technology (Caltech) have shown that a highly
specific intrabody (an antibody fragment that works against a target inside a cell) is
capable of stalling the development of Huntington's disease in a variety of mouse models.
"Gene therapy in these models successfully attenuated the symptoms of Huntington's
disease and increased life span," notes Paul Patterson, the Anne P. and Benjamin F.
Biaggini Professor of Biological Sciences. Patterson is the senior investigator on the
study, which was published in the October 28 issue of the Journal of Neuroscience.
Huntington's disease is a neurodegenerative disorder with a genetic basis. The disorder
has its roots in a mutation in a protein called huntingtin, or Htt. (The gene itself is
also referred to as the huntingtin gene.) All versions of the Htt gene have repeats of a
particular trio of nucleotides—specifically, C, A, and G, which together code for the
amino acid glutamine. In most people, that trio is repeated between 10 and 35 times. But
in people who develop Huntington's disease, that genetic stutter goes on and on; they will
have anywhere between 36 to upwards of 120 repeats. The result of all these repeats? An
abnormally long version of the Htt protein, which gets chopped up into smaller, toxic
pieces and accumulates in nerve cells, debilitating them.
Link
Carotenoids may cut risk of
metabolic syndrome in half
Increased intakes of antioxidant carotenoids, and particularly lycopene, may reduce the
risk of developing the metabolic syndrome by about 50%, according to a new study.
Link
Chance of stroke rises with less
magnesium in the blood
Researchers at the University of Minnesota School of Public Health have found that low
blood levels of magnesium may increase the risk of stroke by 25%.
Link
Compounds in Berries May Lessen Sun
Damage
New research shows that a compound found in berries, nuts and other fruits might help
prevent wrinkles and repair skin damage caused by the sun.
Link
Drug shows promise in treating
dangerous complication of erectile disorder
Thousands of men are afflicted with an embarrassing and painful condition that triggers
spontaneous, long-lasting erections. There are limited treatment options, but a solution
could be on the way thanks to new research at The University of Texas Health Science
Center at Houston. Priapism is a condition of persistent painful penile erection in the
absence of sexual desire. It is highly associated with sickle cell disease, leukemia and
other blood disorders. It can also result from vasoactive drug abuse. One of the most
dangerous complications seen in priapic patients is penile fibrosis, which can lead to
erectile dysfunction. Priapism can be an urgent urological condition and causes of the
erections lasting at least four hours are unknown. Biochemists in the laboratory of Yang
Xia, M.D., Ph.D., an associate professor at The University of Texas Medical School at
Houston, report that an FDA-approved drug called polyethylene glycol-linked adenosine
deaminase (PEG-ADA) relieved symptoms and a major complication in a pre-clinical study.
Current findings appear online and will be in the March 2010 print issue of The FASEB
Journal, the journal of The Federation of American Societies for Experimental Biology.
Link
Happy solar-cell scientists
A series of joint sub-projects and work-packages has enabled the scientists to develop a
new, less expensive grade of raw material for solar cells. And the best news is that the
new modules are just as efficient as current solar cells. SINTEF has coordinated this
major programme that rejoices in the long name: “Development of solar-grade silicon
feedstock for crystalline wafers and cells by purification and crystallisation”,
which has been simplified to “FoXy”. Together with ten other participants from
various European nations, the scientists have been developing a “good enough”
grade of silicon for solar cell production. And there has been no lack of results: a
series of joint sub-projects and work-packages has enabled the scientists to develop a
new, less expensive grade of raw material for solar cells. And the best news is that the
new modules are just as efficient as current solar cells.
Link
Harvesting energy from nature's
motions
By taking advantage of the vagaries of the natural world, Duke University engineers have
developed a novel approach that they believe can more efficiently harvest electricity from
the motions of everyday life. Energy harvesting is the process of converting one form of
energy, such as motion, into another form of energy, in this case electricity. Strategies
range from the development of massive wind farms to produce large amounts of electricity
to using the vibrations of walking to power small electronic devices. Although motion is
an abundant source of energy, only limited success has been achieved because the devices
used only perform well over a narrow band of frequencies. These so-called
"linear" devices can work well, for example, if the character of the motion is
fairly constant, such as the cadence of a person walking. However, as researchers point
out, the pace of someone walking, as with all environmental sources, changes over time and
can vary widely. "The ideal device would be one that could convert a range of
vibrations instead of just a narrow band," said Samuel Stanton, graduate student in
Duke's Pratt School of Engineering, working in the laboratory of Brian Mann, assistant
professor of mechanical engineering and materials sciences. The team, which included
undergraduate Clark McGehee, published the results of their latest experiments early
online in Applied Physics Letters. "Nature doesn't work in a single frequency, so we
wanted to come up with a device that would work over a broad range of frequencies,"
Stanton said. "By using magnets to 'tune' the bandwidth of the experimental device,
we were able verify in the lab that this new non-linear approach can outperform
conventional linear devices." Although the device they constructed looks deceptively
simple, it was able to prove the team's theories on a small scale. It is basically a small
cantilever, several inches long and a quarter inch wide, with an end magnet that interacts
with nearby magnets. The cantilever base itself is made of a piezoelectric material, which
has the unique property of releasing electrical voltage when it is strained.
Link
Heavy metals accumulate more in
some mushrooms than in others
A research team from the University of Castilla-La Mancha (UCLM) has analysed the presence
of heavy metals in 12 species of mushroom collected from non-contaminated natural areas,
and has found that the levels vary depending on the type of mushroom. The results of the
study, which appears this month in the journal Biometals, show that the largest quantities
of lead and neodymium are found in chanterelles. "The aim was to find out if there is
a connection between the concentrations of specific heavy metals detected in the
mushrooms, based on three factors: the type of substrate, the study area and the species
of mushroom. The third was the determining factor", explains Juan Antonio Campos,
principal author of the study and researcher at the Department of Crop Production and
Agricultural Technology at UCLM. The researchers have analysed the presence of lead (Pb),
neodymium (Nd), thorium (Th) and uranium (U) in a hundred samples of 12 different species
of common mushroom, both edible and non-edible, collected from non-contaminated zones in
the Ciudad Real province. They were collected from wooded areas comprising Holm oak,
Kermes oak, Pyrenean oak, Pine and Cistus. The results of the study, published this month
in the journal Biometals, reveal that there are 'considerable' quantities of the four
metals in all the species examined, as well as significant differences in the capacity for
accumulation of these elements depending on the species. The analysis of these heavy
metals – which can be toxic to humans – was carried out using X-ray fluorescence
spectometry, a technique that enables a sample's composition to be detected and quantified
using X-rays. The highest levels of neodymium (7.1 micrograms/gram) and lead (4.86 µg/g)
were found in the chanterelle (Cantharellus cibarius), a mushroom widely used in European
cuisine. This mushroom grows in the shadow of Holm oaks, Cork oaks and oaks, and is
ectomycorrhizal (it clings to the external roots of plants to exchange nutrients), thereby
it has direct contact with the mineral particles of the soil.
Link
Immune-Boosting Powers of Curcumin
Are Pinpointed
Using solid-state NMR spectroscopy, Ramamoorthy and his co-workers report that molecules
of curcumin insert themselves into cell membranes and make the membranes more stable and
orderly.
Link
Immunotherapy demonstrates
long-term success in treating lymphoma
Targeted immunotherapy has been an attractive new therapeutic area for a number of cancers
because it has the potential to destroy tumor cells without damaging surrounding normal
tissue. New study results demonstrate high success rates using specialized white blood
cells to prevent or treat lymphoma associated with the Epstein-Barr virus (EBV-lymphoma)
in patients who have received a hematopoietic stem cell transplant (HSCT). This study was
pre-published online today in Blood, the official journal of the American Society of
Hematology. Lymphoma is a cancer of white blood cells called lymphocytes that are largely
responsible for maintaining the body's immunity, and EBV is one of the most common human
viruses that can have a long-lasting impact on the body's immune system.
Immune-compromised patients who receive HSCT, especially from mismatched donors or matched
but unrelated donors, may be at higher risk of developing EBV-lymphoma than other
patients. Previous studies have suggested that EBV-lymphoma occurs most often in the first
few months post-transplant. The researchers hypothesized that aggressive EBV-lymphomas may
be responsive to control or eradication with EBV-specific cytotoxic T lymphocyte (CTL)
treatment. (CTLs are highly specialized white blood cells that build the body's defenses
against disease.) To test their theory, the team infused EBV-specific CTL lines into two
groups of patients: those who were undergoing HSCT and were at high risk of developing
EBV-lymphoma, and patients who had already developed lymphoma. The study reported that CTL
treatment successfully prevented the development of EBV-lymphoma in all 101 patients in
the at-risk group who received the therapy prophylactically and achieved sustained
complete remission in 11 of the 13 patients (85 percent) treated therapeutically (those
who already had the disease). "Therapy with EBV-specific CTLs was effective for these
severely immunocompromised patients. The CTLs successfully reached tumors, multiplied, and
were able to kill the tumor cells," said lead study author Helen Heslop, MD, of the
Center for Cell and Gene Therapy at Baylor College of Medicine, The Methodist Hospital,
and Texas Children's Hospital.
Link
Inhibitor of heat shock protein is
a potential anticancer drug, Penn study finds
Like yoga for office drones, cells do have coping strategies for stress. Heat, lack of
nutrients, oxygen radicals – all can wreak havoc on the delicate internal components
of a cell, potentially damaging it beyond repair. Proteins called HSPs (heat shock
proteins) allow cells to survive stress-induced damage. Scientists have long studied how
HSPs work in order to harness their therapeutic potential. Donna George, PhD, Associate
Professor of Genetics, and Julie Leu, PhD, Assistant Professor of Genetics, both at the
University of Pennsylvania School of Medicine, in collaboration with the lab of Maureen
Murphy, PhD at Fox Chase Cancer Center, identified a small molecule that inhibits the heat
shock protein HSP70. They also showed that the HSP inhibitor could stop tumor formation
and significantly extend survival of mice. They describe their findings in this month's
issue of Molecular Cell. HSP70 is an intracellular quality control officer, refolding
misfolded proteins and preventing protein aggregation, which among other disorders, is
associated with neurodegenerative diseases. HSP70 also ferries proteins to their proper
intracellular locations. Tumor cells, which face an abundance of cellular stresses,
typically overexpress HSP70, making it a potentially interesting anticancer target. The
cancer microenvironment exposes malignant cells to a variety of stressful conditions that
promote protein misfolding. HSP70 helps cancer cells deal with this stress. Unlike normal
cells, which typically express little, if any, of HSP70, cancer cells contain high levels
of this protein all of the time. Indeed, HSP70 has been termed a cancer-critical survival
factor, since cancer cells probably require the actions of this protein to survive the
protein-altering adverse conditions. The inhibitor, called PES, interferes with the HSP70
activities that the cancer cell needs to survive, so by targeting HSP70, one can target
the cancer cell. The investigators showed that PES interacts with HSP70 by blocking its
stress-relieving functions. It also induces HSP70-dependent cell death by disrupting the
cell's ability to remove damaged components. Paradoxically for a compound first identified
for blocking the cell-death pathway of apoptosis, PES does kill cells, but by a different
mechanism.
Link
Interactions with aerosols boost
warming potential of some gases
For decades, climate scientists have worked to identify and measure key substances --
notably greenhouse gases and aerosol particles -- that affect Earth's climate. And they've
been aided by ever more sophisticated computer models that make estimating the relative
impact of each type of pollutant more reliable. Yet the complexity of nature -- and the
models used to quantify it -- continues to serve up surprises. The most recent? Certain
gases that cause warming are so closely linked with the production of aerosols that the
emissions of one type of pollutant can indirectly affect the quantity of the other. And
for two key gases that cause warming, these so-called "gas-aerosol interactions"
can amplify their impact. "We've known for years that methane and carbon monoxide
have a warming effect," said Drew Shindell, a climate scientist at the NASA Goddard
Institute for Space Studies (GISS) in New York and lead author of a study published this
week in Science. "But our new findings suggest these gases have a significantly more
powerful warming impact than previously thought."
Link
Lessons from flu seasons past
Pregnant women who catch the flu are at serious risk for flu-related complications,
including death, and that risk far outweighs the risk of possible side effects from
injectable vaccines containing killed virus, according to an extensive review of published
research and data from previous flu seasons. The review, a collaboration among scientists
from the Johns Hopkins Children's Center, Emory University and Cincinnati Children's
Hospital, and published online Oct. 22 in the American Journal of Obstetrics &
Gynecology, found substantial and persistent evidence of high complication risk among
pregnant women -- both healthy ones and those with underlying medical conditions --
infected with the flu virus, while confirming vaccine safety. The findings, researchers
say, solidify existing CDC recommendations that make pregnant women the highest-priority
group to receive both the H1N1 and seasonal flu vaccines. "The lessons learned from
flu outbreaks in the distant and not-too-distant past are clear and so are the
messages," says lead investigator Pranita Tamma, M.D., an infectious disease
specialist at the Johns Hopkins Children's Center. "If you are an expectant mother,
get vaccinated. If you are a physician caring for pregnant women, urge your patients to
get vaccinated." Because even healthy pregnant women end up in the hospital with
preventable flu complications -- some devastating and some fatal -- at a rate far higher
than that of other adults, and because of the proven effectiveness and overall safety
record of flu vaccines, all pregnant women should consider getting vaccinated to prevent
complications in both the expectant mother and her offspring, researchers say.
Link
Low Vitamin D Levels Explains Most
ESRD Risk in African Americans
ow levels of vitamin D may account for nearly 60 percent of the elevated risk of end-stage
renal disease (ESRD) in African Americans, according to a report in the December Journal
of the American Society of Nephrology (JASN). "Our study adds to previous evidence
linking vitamin D deficiency to the progression of kidney disease and the need for
dialysis," comments Michal L. Melamed, MD, of Albert Einstein College of Medicine
(Bronx, NY). "It also explains a fair amount of the increased risk of ESRD in African
Americans." Vitamin D is obtained from sun exposure, food and food supplements.
Link
Nano-Scale Drug Delivery For
Chemotherapy
Going smaller could bring better results, especially when it comes to cancer-fighting
drugs. Duke University bioengineers have developed a simple and inexpensive method for
loading cancer drug payloads into nano-scale delivery vehicles and demonstrated in animal
models that this new nanoformulation can eliminate tumors after a single treatment. After
delivering the drug to the tumor, the delivery vehicle breaks down into harmless
byproducts, markedly decreasing the toxicity for the recipient. Nano-delivery systems have
become increasingly attractive to researchers because of their ability to efficiently get
into tumors. Since blood vessels supplying tumors are more porous, or leaky, than normal
vessels, the nanoformulation can more easily enter and accumulate within tumor cells. This
means that higher doses of the drug can be delivered, increasing its cancer-killing
abilities while decreasing the side effects associated with systematic chemotherapy
Link
New Research Study Targets Tinnitus
with Transcranial Magnetic Stimulation
Chronic tinnitus, noise or ringing in the ears, is a symptom associated with many forms of
hearing loss or other health problems. There are no effective treatments for this
condition, which can become so severe that it may be difficult to hear, work, or even
sleep. Researchers at the University of Pennsylvania are now testing a non-invasive
treatment – transcranial magnetic stimulation (TMS) – to target overactive areas
in the brain responsible for tinnitus. TMS was recently approved by the United States Food
and Drug Administration (FDA) for treatment of depression and has been extensively tested
in Europe for tinnitus. Michael Ruckenstein, MD, Professor of Otorhinolaryngology: Head
and Neck Surgery at the University of Pennsylvania School of Medicine, will lead the
study, in conjunction with John O’Reardon, Associate Professor of Psychiatry and
Director of Penn’s Transcranial Magnetic Stimulation Program. Study participants will
undergo 4 weeks (20 sessions) of TMS sessions to see if the treatment improves tinnitus.
For those who respond, there will be a 3 month extension phase (8 sessions – 4 in
month 1, 2 each in months 2 and 3).
Link
November is Vitamin D Awareness
Month in Canada
The Vitamin D Society is a Canadian non-profit group organized to increase awareness of
the many health conditions strongly linked to vitamin D deficiency and to encourage all
Canadians to have their vitamin D blood levels tested annually. Optimal vitamin D blood
levels are 100-150 nmol/L as measured by a calcidiol blood test.
Link
Pregnant women risk early delivery
from using psychiatric medication
The odds triple for premature child delivery pregnant women with a history of depression
who used psychiatric medication, according to a new study. Researchers at the University
of Washington, University of Michigan and Michigan State University found that a
combination of medication use and depression – either before or during pregnancy
– was strongly linked to delivery before 35 weeks' gestation. Amelia Gavin, lead
author and UW assistant professor of social work, said the findings highlight the need for
carefully planned studies that can clarify associations between depression, psychiatric
medications and preterm delivery. "Women with depression face difficult decisions
regarding the benefits and risks of using psychotropic medications in pregnancy,"
Gavin said. "Therefore, a focus on disentangling medication effects and depression
effects on mother and offspring health should be a major clinical priority."
"Medication use may be an indicator of depressive symptom severity, which is a direct
or indirect contributing factor to pre-term delivery," added Kristine Siefert,
co-author and a Michigan professor of social work. Most physicians initiated preterm
deliveries after the women suffered complications, such as pre-eclampsia, poor fetal
growth or acute hemorrhage. The study examined the associations among maternal depression,
psychiatric medication use in pregnancy and preterm delivery among women in five Michigan
communities who received prenatal care at one of 52 participating clinics between
September 1998 and June 2004These women had to be at least 15 years old, with no history
of diabetes, and were 15 to 27 weeks pregnant.
Link
Progress made on group B
streptococcus vaccine
Scientists supported by the National Institute of Allergy and Infectious Diseases (NIAID),
part of the National Institutes of Health, have completed a Phase II clinical study that
indicates a vaccine to prevent Group B Streptococcus (GBS) infection is possible. GBS is
the most common cause of sepsis and meningitis in newborns in the United States, according
to the Centers for Disease Control and Prevention (CDC). It can also cause severe illness
in pregnant women, the elderly and adults with chronic illnesses. Colonization of the
genital or gastrointestinal tract is a critical risk factor for infections due to GBS. The
researchers, led by Sharon L. Hillier, Ph.D., from the Magee-Womens Research Institute at
the University of the Pittsburgh, found that the vaccine used in the study can cause a
modest but sustained reduction in genital and gastrointestinal GBS bacterial colonization.
The GBS bacterium, which is commonly found in the gut and genital tracts, can infect the
fetus during gestation and birth or after delivery. Pregnancy-related infections can lead
to serious consequences for women including stillbirth. Currently, one-third of pregnant
women in the United States test positive for asymptomatic GBS and receive antibiotics
during labor to prevent infection of the newborn. Although this antibiotic strategy is
highly effective, the broad use of antibiotics in pregnant women is of concern to public
health officials. Many women are allergic to penicillin and penicillin-type antibiotics
that are the preferred treatment, and GBS is increasingly resistant to other common
antibiotics. Dr. Hillier and her colleagues conducted a double-blind, randomized trial of
the GBS vaccine that included a total of 650 sexually active, non-pregnant women ages 18
to 40 who were GBS-negative in the vagina and rectum at the beginning of the study.
Approximately one-half of the women were in the control group and received a licensed
tetanus and diphtheria toxoids (Td) vaccine instead of the GBS vaccine. The women were
followed for 18 months after they were vaccinated and checked for GBS bacteria at regular
intervals. The goal of the study was to see whether vaccination could prevent or decrease
colonization by one of the most common subtypes of GBS bacteria: Type III.
Link
Research suggests link between
facial structure and aggression
Angry words and gestures are not the only way to get a sense of how temperamental a person
is. According to new findings in Psychological Science, a journal of the Association for
Psychological Science, a quick glance at someone's facial structure may be enough for us
to predict their tendency towards aggression. Facial width-to-height ratio (WHR) is
determined by measuring the distance between the right and left cheeks and the distance
from the upper lip to the mid-brow. During childhood, boys and girls have similar facial
structures, but during puberty, males develop a greater WHR than females. Previous
research has suggested that males with a larger WHR act more aggressively than those with
a smaller WHR. For example, studies have shown that hockey players with greater WHR earn
more penalty minutes per game than players with lower WHR. Psychologists Justin M. Carré,
Cheryl M. McCormick, and Catherine J. Mondloch of Brock University conducted an experiment
to see if it is possible to predict another person's propensity for aggressive behavior
simply by looking at their photograph. Volunteers viewed photographs of faces of men for
whom aggressive behavior was previously assessed in the lab. The volunteers rated how
aggressive they thought each person was on a scale of one to seven after viewing each face
for either 2000 milliseconds or 39 milliseconds.
Link
Researchers develop innovative
imaging system to study sudden cardiac arrest
A research team at Vanderbilt University has developed an innovative optical system to
simultaneously image electrical activity and metabolic properties in the same region of a
heart, to study the complex mechanisms that lead to sudden cardiac arrest. Tested in
animal models, the system could dramatically advance scientists' understanding of the
relationship between metabolic disorders and heart rhythm disturbances in humans that can
lead to cardiac arrest and death, and provide a platform for testing new treatments to
prevent or stop potentially fatal irregular heartbeats, known as arrhythmias. The research
is supported in part by the National Heart, Lung, and Blood Institute (NHLBI), part of the
National Institutes of Health. The design and use of the dual camera system is described
in the Nov.1 issue of Experimental Biology and Medicine. Additional support for the
project has also been provided by the Vanderbilt Institute for Integrative Biosystems
Research and Education (VIIBRE), the American Heart Association, and the Simons Center for
Systems Biology at the Institute for Advanced Study. "The challenge in understanding
cardiac rhythm disorders is to discern the dynamic relationship between multiple cardiac
variables," said one of the coauthors of the paper and the project's principal
investigator, John P. Wikswo, Ph.D., Gordon A. Cain University Professor and VIIBRE
director. "This dual camera system opens up a new window for correlating metabolic
and electrophysiological events, which are usually studied independently." The
11-year-old research project would have been terminated this year due to lack of funding,
according to Wikswo. But a $566,000 American Recovery and Reinvestment Act grant from the
NHLBI is enabling the 13-member research team to continue developing and testing the
innovative optical system. Recovery Act funds are also allowing the team to purchase a
pair of $60,000 high-speed and highly sensitive digital cameras to record the changes in
the metabolic and electrical activity of isolated cardiac tissue using low-intensity
fluorescent dyes under conditions associated with heart failure, ischemia, fibrillation
and other pathological circumstances.
Link
Seasonal flu vaccine ups risk of
pandemic flu
Earlier this year, Dutch scientists showed that vaccinating mice against seasonal strains
of flu rendered the animals unnecessarily vulnerable to dying if they later encountered a
pandemic flu strain.
Link
Sight gone, but not necessarily
lost?
Like all tissues in the body, the eye needs a healthy blood supply to function properly.
Poorly developed blood vessels can lead to visual impairment or even blindness. While many
of the molecules involved in guiding the development of the intricate blood vessel
architecture are known, only now are we learning how these molecules work and how they
might affect sight. Reporting in the Oct. 16 issue of Cell, researchers at the Johns
Hopkins School of Medicine find that when some cells in the mouse retina are not properly
fed by blood vessels, they can remain alive for many months and can later recover some or
all of their normal function, suggesting that similar conditions in people may also be
reversible. "This finding is intriguing," says Jeremy Nathans, M.D., Ph.D., a
professor of molecular biology and genetics, neuroscience and ophthalmology at Johns
Hopkins and a Howard Hughes Medical Institute investigator. "It suggests that neurons
in the retina can survive for an extended period of time even though they have been
functionally silenced."
Link
Stress-induced changes in brain
circuitry linked to cocaine relapse
Stress-evoked changes in circuits that regulate serotonin in certain parts of the brain
can precipitate a low mood and a relapse in cocaine-seeking, based on mouse studies
published online this week in the Proceedings of the National Academy of Sciences Early
Edition."The impetus for this research was our interest in how stress alters the
brain's cell receptors and protein signals in ways that lead to mood changes, depression,
anxiety, and drug seeking," said Dr. Michael Bruchas, acting instructor of
pharmacology at the University of Washington (UW), who with Dr. Benjamin Land, a former UW
doctoral student now in the Department of Psychiatry at Yale University, co-led the recent
study of the adverse effects of stress-activated brain pathways. The senior author was Dr.
Charles Chavkin, the Allan and Phyllis Treuer Professor of Pharmacology and director of
the UW Center for Drug Addiction Research A common belief is that drug seeking is
regulated by dopamine, a chemical nerve signal associated with motivating and rewarding
behavior. Dopamine may still have a key role, the researchers noted, which is why they
were surprised to find harmful effects of stress converging in a brain region-- the dorsal
raphe nucleus --where nerve cells that use serotonin are abundant. These nerve cells also
project to other structures found on either side of the brain -- the nucleus accumbens --
which are thought to play roles in feeding and drug addiction. Serotonin is a chemical
nerve signal that has been associated with wake and sleep cycles, mood, anger, status and
aggression
Link
Tests on treasured maize ignite
fears in Mexico
As scientists race the clock to increase food production worldwide, new trials to plant
genetically-modified maize have stoked anger in Mexico, the cradle of corn.
Link
The role of biomedical research in
malaria eradication
Although malaria has been controlled in many local and regional populations, the permanent
elimination of malaria parasites throughout the world remains an elusive goal, and the
disease continues to claim nearly one million lives each year. In 2007, Bill and Melinda
Gates called for a renewed effort to eradicate malaria worldwide. Some skeptics have
questioned the feasibility of doing so because of failed attempts to eradicate malaria in
the 20th century. In a new commentary, National Institutes of Health scientists B. Fenton
Hall, M.D., Ph.D., and Anthony S. Fauci, M.D., director of the NIH National Institute of
Allergy and Infectious Diseases (NIAID), discuss the lessons learned from past attempts to
eradicate malaria and identify key challenges to achieving success today. The renewed
effort to eradicate malaria will require a long-term commitment that incorporates multiple
activities, interventions and approaches, they assert. As success in controlling malaria
is achieved, the behavior and distribution of malaria parasites and the mosquitoes that
spread them are likely to change. Scientists must be prepared to anticipate these changes
and alter their strategies to keep ahead of them by developing a robust pipeline of new
tools and interventions. The authors note that such a pipeline will require a sustained
research effort, as NIAID recently outlined in the Strategic Plan for Malaria Research and
the NIAID Malaria Research Agenda. NIAID is the lead U.S. government agency that supports
basic biomedical and clinical research in malaria.
Link
This is your brain on fatty acids
Saturated fats have a deservedly bad reputation, but Johns Hopkins scientists have
discovered that a sticky lipid occurring naturally at high levels in the brain may help us
memorize grandma's recipe for cinnamon buns, as well as recall how, decades ago, she
served them up steaming from the oven. The Hopkins team, reporting Oct. 29 in Neuron,
reveals how palmitate, a fatty acid, marks certain brain proteins – NMDA receptors
– that need to be activated for long-term memory and learning to take place. The
fatty substance directs the receptors to specific locations in the outer membrane of brain
cells, which continually strengthen and weaken their connections with each other,
sculpting and resculpting new memory circuits. Moreover, the researchers report, this
fatty modification is a reversible process, with some sort of on-off switch, offering
possibilities for manipulating it to enhance or even, perhaps, erase memory. "Before
now, no one knew that NMDA receptors change in response to the addition of
palmitate," says Richard Huganir, Ph.D., professor and director of the Solomon H.
Snyder Department of Neuroscience at Johns Hopkins. Scientists have known that a brain
signaling chemical called glutamate normally activates NMDA receptors, allowing two
neurons to communicate with one another. However, they were less certain what allowed this
receptor to assemble properly, or what caused it to make its way to the synapse, the
specialized part of nerve cells where communication takes place. The discovery emerged
from work with live neurons in a dish, to which the scientists first fed radioactive
palmitate, then separated out the NMDA receptors. By tracking radioactivity on X-ray film,
they were able to determine that the fat had attached to the NMDA receptors.Next, the
scientists put both normal and altered NMDA receptors into non-brain cells that don't
normally manufacture their own NMDA receptors. By tracking the radioactive fat, they were
able to determine where on the NMDA receptor the fat had attached.
Link
Thousands of children on
antidepressants
Thousands of children are being prescribed anti-depressants and "chemical cosh"
drugs unnecessarily, the Conservatives have said.
Link
Tocotrienol Build-Up in Tumors Is
Critical for Anti-Cancer Benefits
A new study from Japan reports that tocotrienols, members of the vitamin E family, may
exert their anti-cancer benefits by accumulating in cancer cells and delaying tumor
growth.
Link
Treating mild iodine deficiency
boosts brain power
Iodine supplements may improve mental function in children with even mild deficiencies in
the nutrient, a small study suggests.
Link
Unlocking Mysteries of the Brain
with PET
Inflammatory response of brain cells—as indicated by a molecular imaging
technique—could tell researchers more about why certain neurologic disorders, such as
migraine headaches and psychosis in schizophrenic patients, occur and provide insight into
how to best treat them, according to two studies published in the November issue of The
Journal of Nuclear Medicine. By using positron emission tomography (PET)—a
noninvasive molecular imaging technique—researchers were to able to identify
neuroinflammation, which is marked by activated microglia cells (brain cells that are
responsive to injury or infection of brain tissue) in patients with schizophrenia and in
animal models with migraines. Although neuroinflammation has been shown to play a major
role in many neurodegenerative disorders––such as multiple sclerosis,
Parkinson’s disease and Alzheimer’s disease––only limited data exists
about the role of neuroinflammation in schizophrenia and migraines. The two studies in The
Journal of Nuclear Medicine are the first to identify neuroinflammation in specific
regions of the brain—a development which could be used to effectively evaluate the
treatment response to anti-inflammatory drugs and become transformative for diagnosis and
care. “This study shows that molecular imaging can play an important role in better
understanding the processes involving psychiatric and other neurological disorders,”
said Janine Doorduin, M.Sc., a researcher at the University Medical Center Groningen in
the Netherlands and lead author of “Neuroinflammation in Schizophrenia-Related
Psychosis: A PET Study.” Doorduin added: “Without molecular imaging, the only
way to look at inflammation in the brain, as well as other molecular processes, would be
to use post-mortem brains.”
Link
USU scientists report major advance
in human antibody therapy against deadly Nipah virus
A collaborative research team from the Uniformed Services University of the Health
Sciences (USU), Australian Animal Health Laboratory and National Cancer Institute, a
component of the National Institutes of Health, reports a major step forward in the
development of an effective therapy against two deadly viruses, Nipah virus and the
related Hendra virus. The results of this finding appear Oct. 30, 2009, in the open access
journal PLoS Pathogens at http://dx.plos.org/10.1371/journal.ppat.1000642.Nipah and Hendra
viruses are found in Pteropid fruit bats (flying foxes) and are characterized by their
recent emergence as agents capable of causing illness and death in domestic animals and
humans. In experiments carried out in ferrets at the Australian Animal Health Laboratory
in Geelong, Victoria, Australia, where there is a high-level safety and security facility
for working with live Nipah and Hendra viruses, the team of researchers demonstrated that
giving an anti-virus human monoclonal antibody therapy after exposure to Nipah virus
protected the animals from disease. "These findings are extremely encouraging and
clearly suggest the potential that a treatment for Hendra virus infection in a similar
manner should be possible, given the very strong cross-reactive activity this antibody has
against Hendra virus," said Deborah Middleton, D.V.M., Ph.D., who directed the animal
experiments at the Australian Animal Health Laboratory. Recent earlier work at the
National Cancer Institute and USU resulted in the discovery and development of a human
monoclonal antibody, m102.4, which could attack a critical component of both the Nipah and
Hendra viruses. Antibodies—proteins found in blood or other bodily fluids of
vertebrates—are used by the immune system to identify and neutralize viruses and
bacteria.
Link
Why do psychologists reject
science?
Psychologists led by Timothy B. Baker of the University of Wisconsin charge that many
clinicians fail to "use the interventions for which there is the strongest evidence
of efficacy" and "give more weight to their personal experiences than to
science.
Link
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