Brown marmorated stink bugs cause millions of dollars in crop losses across the United States because of the damage their saliva does to plant tissues. Researchers at Penn State have developed methods to extract the insect saliva and identify the major protein components, which could lead to new pest control approaches.”Until now, essentially nothing was known about the composition of stink bug saliva, which is surprising given the importance of these insects as pests and the fact that their saliva is the primary cause of feeding injury to plants and crop losses,” said Gary Felton, professor and head of the Department of Entomology. “Other than using synthetic pesticides, there have been few alternative approaches to controlling these pests. By identifying the major protein components of saliva, it now may be possible to target the specific factors in saliva that are essential for their feeding and, therefore, design new approaches for controlling stink bugs.”The team reported its results in PLOS ONE.According to Felton, stink bugs produce two types of saliva that are required for successful feeding. Watery saliva helps stink bugs to digest their food. Sheath saliva surrounds stink bugs’ mouthparts and hardens to prevent spillage of sap during feeding. The hardened “sheath” remains attached to the plant when the insect is finished feeding.”Unlike a chewing insect, which causes damage by removing plant tissue, stink bugs pierce plant tissue and suck nutrients from the plant,” said Michelle Peiffer, research support assistant. “During this process, stink bugs also deposit saliva onto the plant. The interaction between this saliva and the plant is what causes the cosmetic and physiological changes that make crops unmarketable.”To extract the two types of saliva from brown marmorated stink bugs, Felton and Peiffer first collected adult bugs from homes and fields in central Pennsylvania and maintained them in their laboratory.The researchers chilled the insects on ice. As the insects returned to room temperature, their watery saliva was secreted from the tips of their beaks. …Read more
In the Proceedings of the National Academy of Sciences, a team of scientists at Brown University reports a major step forward in determining the specific behavior of the ubiquitous enzyme PP1 implicated in a wide range of diseases including cancer.PP1, whose role is to enable the passage of molecular messages among cells, is found pretty much everywhere in the body. Its wide range of responsibilities means it is essential to many healthy functions and, when things go wrong, to diseases. But its very versatility has prevented it from being a target for drug development, said Rebecca Page, associate professor of biology at Brown and the paper’s corresponding author.”The amazing thing about PP1 is that no one has wanted to touch it for the most part as a drug target because PP1 is involved in nearly every biological process,” Page said. “It’s not like you could just target the PP1 active site for, let’s say, diabetes because then you are going to affect drug addiction, Alzheimer’s disease and all these other diseases at the same time.”In other words, make a medicine to block PP1 in one bodily context and you’d ruin it in all other contexts. Structural biologists such as Page and Brown co-author Wolfgang Peti have therefore been eager to learn what makes PP1 behave in specific ways in specific situations.The key is the way PP1 binds with more than 200 different regulatory proteins. Scientists know of these proteins and know the sequences of amino acids that compose them, but they don’t know their structure or how they actually guide PP1.”The ability to predict how these PP1 interacting proteins bind PP1 from sequence alone is still missing,” Page and her colleagues wrote in PNAS.Now, through experiments in which her team including lead author Meng Choy combined NMR spectroscopy, X-ray crystallography and techniques in biochemistry, she has learned how PP1 binds to a targeting protein called PNUTS, forming “binding motifs.” That knowledge, combined with what she learned in earlier studies about two other targeting proteins — NIPP1 and spinophilin — has allowed her team to predict how PP1 binds with 43 of the 200 regulatory proteins that give it specific behavior.”What this work in conjunction with two of our previous structures allowed us to do was to define two entirely new motifs,” she said. “From that, comparing the sequences with the known proteins that interact with PP1 whose structures we don’t have, we were able to predict that 20 percent of them likely interact in a way that is similar to these three proteins.”So by resolving the structure of just three proteins with PP1, Page now has the means to understand the binding of many proteins without having to resolve their structure. Instead she need only know the few motifs and the proteins’ sequences.As for PP1’s interactions with the other 80 percent or so of regulatory proteins, those remain a mystery. But Page said the success her team has had in the lab working with PP1 and resolving key motifs makes her optimistic that those interactions can be solved, too.Story Source:The above story is based on materials provided by Brown University. Note: Materials may be edited for content and length.Read more
When a fetal heartbeat pattern becomes irregular during labor, many practitioners give oxygen to the mother. But questions remain whether this oxygen supplementation benefits the fetus or may actually be potentially harmful.A clinical opinion written by third year resident Maureen Hamel, MD, along with maternal-fetal medicine specialists Brenna Anderson, MD and Dwight Rouse, MD, of the Department of Obstetrics and Gynecology at Women & Infants Hospital of Rhode Island and The Warren Alpert Medical School of Brown University, has been published in the January 10, 2014 online edition of the American Journal of Obstetrics & Gynecology.The manuscript, entitled “Oxygen for intrauterine resuscitation: Of unproved benefit and potentially harmful,” aimed to make recommendations about the safety of the use of maternal oxygen supplementation in laboring women.According to lead author Dr. Hamel, “Maternal oxygen is often given to laboring women to improve fetal metabolic status or in an attempt to alleviate non-reassuring fetal heart rate patterns. However, there are only two randomized trials investigating the use of maternal oxygen supplementation in laboring women. These studies did not find that supplementation is likely to benefit the fetus and may even be harmful.”Based on their research, the team concludes that until it is studied properly in a randomized clinical trial, maternal oxygen supplementation in labor should be reserved for maternal hypoxia (lack of oxygen) and should not be considered an indicated intervention for non-reassuring fetal status.Story Source:The above story is based on materials provided by Women & Infants Hospital. Note: Materials may be edited for content and length.Read more
Diseases that are common in managed honeybee colonies are now widespread in the UK’s wild bumblebees, according to research published in Nature. The study suggests that some diseases are being driven into wild bumblebee populations from managed honeybees.Dr Matthias Frst and Professor Mark Brown from Royal Holloway University of London (who worked in collaboration with Dr Dino McMahon and Professor Robert Paxton at Queen’s University Belfast, and Professor Juliet Osborne working at Rothamsted Research and the University of Exeter) say the research provides vital information for beekeepers across the world to ensure honeybee management supports wild bee populations.Dr Frst, from the School of Biological Sciences at Royal Holloway, said: “Wild and managed bees are in decline at national and global scales. Given their central role in pollinating wildflowers and crops, it is essential that we understand what lies behind these declines. Our results suggest that emerging diseases, spread from managed bees, may be an important cause of wild bee decline.”This research assessed common honeybee diseases to determine if they could pass from honeybees to bumblebees. It showed that deformed wing virus (DWV) and the fungal parasite Nosema ceranae — both of which have major negative impacts on honeybee health — can infect worker bumblebees and, in the case of DWV, reduce their lifespan.Honeybees and bumblebees were then collected from 26 sites across the UK and screened for the presence of the parasites. Both parasites were widespread in bumblebees and honeybees across the UK.Dr Frst explained: “One of the novel aspects of our study is that we show that deformed wing virus, which is one of the main causes of honeybee deaths worldwide, is not only broadly present in bumblebees, but is actually replicating inside them. This means that it is acting as a real disease; they are not just carriers.”The researchers also looked at how the diseases spread and studied genetic similarities between DWV in different pollinator populations. Three factors suggest that honeybees are spreading the parasites into wild bumblebees: honeybees have higher background levels of the virus and the fungus than bumblebees; bumblebee infection is predicted by patterns of honeybee infection; and honeybees and bumblebees at the same sites share genetic strains of DWV.”We have known for a long time that parasites are behind declines in honeybees,” said Professor Brown. “What our data show is that these same pathogens are circulating widely across our wild and managed pollinators. Infected honeybees can leave traces of disease, like a fungal spore or virus particle, on the flowers that they visit and these may then infect wild bees.”While recent studies have provided anecdotal reports of the presence of honeybee parasites in other pollinators, this is the first study to determine the epidemiology of these parasites across the landscape. …Read more
To develop correctly, baby hearts need rhythm…even before they have blood to pump. “We have discovered that mechanical forces are important when making baby hearts,” said Mary Kathryn Sewell-Loftin, a Vanderbilt graduate student working with a team of Vanderbilt engineers, scientists and clinicians attempting to grow replacement heart valves from a patient’s own cells.In an article published last month in the journal Biomaterials the team reported that they have taken an important step toward this goal by determining that the mechanical forces generated by the rhythmic expansion and contraction of cardiac muscle cells play an active role in the initial stage of heart valve formation.A heart valve is a marvelous device. It consists of two or three flaps, called leaflets, which open and close to control the flow of blood through the heart. It is designed well enough to cycle two to three billion times in a person’s lifetime. (Humans and chickens are outliers: Most other animals, large and small, have hearts that beat about one billion times in their lives.) However, heart valves can be damaged by diseases such as rheumatic fever and cancer, aging, heart attacks and birth defects.”For the last 15 years, people have been trying to create a heart valve out of artificial tissue using brute-force engineering methods without any success,” said Assistant Professor of Biomedical Engineering W. David Merryman. “We decided to take a step back and study how heart valves develop naturally so we can figure out how to duplicate the process.” To do so, they designed a series of experiments with chickens, whose hearts develop in a fashion similar to the human heart.”The discovery that the deformations produced by the beating cardiac muscle cells are important provides an entirely new perspective on the process,” said Merryman, who directed the three-year study.The Vanderbilt effort is part of a broader program to develop artificial organs named the Systems-based Consortium for Organ Design and Engineering (SysCODE). It is a National Institutes of Health “Roadmap” initiative to speed the movement of scientific discoveries from the bench to the bedside.”This is the second major advance that we’ve made,” said Professor of Pharmacology Joey Barnett, co-principal investigator of the heart valve project.Last spring, the Vanderbilt team announced that they had identified the unique genes and molecular pathways associated with valve formation. “These included both genes and pathways that we knew about and several that were previously unknown,” said Barnett, who has studied heart valves for more than 20 years.”The genetic study gave us the list of the basic parts — the hardware — required to build a heart valve and this latest study provides us with the information we need about the environment that is required,” said the biologist. “With this information, we should have what we need to create valvular interstitial cells (VICs), that are the basic building blocks of heart valves.”The heart starts out as a simple, U-shaped tube of tissue. …Read more
Scientists from Aston University (UK) have discovered a potential molecular link between Irisin, a recently identified hormone released from muscle after bouts of exercise, and the aging process.Irisin, which is naturally present in humans, is capable of reprograming the body’s fat cells to burn energy instead of storing it. This increases the metabolic rate and is thought to have potential anti-obesity effects.The research team led by Dr James Brown have proven a significant link exists between Irisin levels in the blood and a biological marker of aging called telomere length. Telomeres are small regions found at the end of chromosomes that shorten as cells within the body replicate. Short telomere length has been linked to many age-related diseases including cancer, heart disease and Alzheimer’s disease.Using a population of healthy, non-obese individuals, the team has shown those individuals who had higher levels of Irisin were found to have longer telomeres. The finding provides a potential molecular link between keeping active and healthy aging with those having higher Irisin levels more ‘biological young’ than those with lower levels of the hormone.Dr James Brown from Aston’s Research Centre for Healthy Ageing, said: “Exercise is known to have wide ranging benefits, from cardiovascular protection to weight loss. Recent research has suggested that exercise can protect people from both physical and mental decline with aging. Our latest findings now provide a potential molecular link between keeping active and a healthy aging process.”Irisin itself is secreted from muscle in response to exercise and is capable of reprograming the body’s fat cells to burn energy instead of storing it. This increases the metabolic rate and is thought to have potential weight loss effects, which in turn could help with conditions such as type-2 diabetes.Story Source:The above story is based on materials provided by Aston University. Note: Materials may be edited for content and length.Read more
A peculiar example of a celestial body, known as a brown dwarf, with unusually red skies has been discovered by a team of astronomers from the University of Hertfordshire’s Centre for Astrophysics Research.Brown dwarfs straddle the line between stars and planets. They are too big to be considered as planets; yet they do not have sufficient material to fuse hydrogen in their cores to fully develop into stars. They are midway in mass between stars, like our Sun, and giant planets, like Jupiter and Saturn. Sometimes described as failed stars, they do not have an internal source of energy — so they are cold and very faint, and keep on cooling over time.The brown dwarf, named ULAS J222711-004547, caught the researchers’ attention for its extremely red appearance compared to “normal” brown dwarfs. Further observations with the VLT (Very Large Telescope) in Chile and the use of an innovative data analysis technique have shown that the reason for its peculiarity is the presence of a very thick layer of clouds in its upper atmosphere.Federico Marocco, who led the research team from the University of Hertfordshire, said: “These are not the type of clouds that we are used to seeing on Earth. The thick clouds on this particular brown dwarf are mostly made of mineral dust, like enstatite and corundum.”Not only have we been able to infer their presence, but we have also been able to estimate the size of the dust grains in the clouds.”The size of the dust grains influences the colour of the sky. In a similar way that the old saying of “Red sky at night, shepherd’s delight. Red sky in the morning, shepherd’s warning” is used at sunrise and sunset to indicate the changing weather, a red sky on the brown dwarf suggests an atmosphere loaded with dust and moisture particles. If our morning skies are red, it is because clear skies to the east permit the sun to light the undersides of moisture-bearing clouds coming in from the west. Conversely, in order to see red clouds in the evening, sunlight must have a clear path from the west in order to illuminate moisture-bearing clouds moving off to the east. …Read more
To date, evidence that mutations in a gene called Indy could increase life span in flies and mimic calorie restriction in mammals has come only from experiments in the lab. A new study finds that the same benefit is present in naturally Indy-mutated flies descended from flies collected in the wild all over the world and going back decades.For years, researchers have been investigating how mutations of a gene called Indy (for “I’m Not Dead Yet”) affect metabolism, life span, and reproductive fitness in both mammals and fruit flies. So far mutations in Indy have been studied experimentally only in the lab. No longer. A new study reports that a particularly important variation of the gene with much the same life-governing consequences has actually been widespread among fruit flies, judging by lines gathered from the wild across the entire globe for 60 years.The naturally occurring variation is the insertion of a transposable element — an invasive snippet of DNA — at a specific position on Indy. Researchers, including Brown University biology professors Stephen Helfand and Robert Reenan, found that the transposable element, called Hoppel, was present to varying extents in 17 of 22 fruit fly lines gathered from all over the world as far back as the middle of last century. Hoppel was present in 100 percent of a captive fly line started in 2006 in Mumbai, India, for example, and 55 percent of flies descended from those gathered in Oahu, Hawaii, in 1955.Helfand recalled that in 2000 when he first published a paper in Science demonstrating the effect of Indy on life span, a couple of reporters asked him why a mutation that conveyed such advantages wasn’t found in the wild.Indeed, 14 years later the prevalence of Hoppel insertion suggests that it has been beneficial to flies in the wild and therefore persisted during their evolution, said Helfand, of Brown’s Department of Molecular Biology, Cellular Biology, and Biochemistry.”It’s kind of remarkable that just the Hoppel in Indy should affect fertility and life span because these flies from around the world are from such differing genetic backgrounds,” said Helfand. “This suggests that we are correct that Indy does play a role in longevity. If it does it in the lab, that’s great, but now we can show that it does it in the wild.”In the study, published online Jan. 31 in the journal Aging, the researchers, led by postdoctoral scholar Chen-Tseh Zhu, describe experiments that confirm that the Hoppel transposon’s presence positively affected life span and fertility in the flies. …Read more
Sep. 12, 2013 — Brown University researchers have traced a genetic deficiency implicated in autism in humans to specific molecular and cellular consequences that cause clear deficits in mice in how well neurons can grow the intricate branches that allow them to connect to brain circuits. The researchers also show in their study (online Sep. 12, 2013, in Neuron) that they could restore proper neuronal growth by compensating for the errant molecular mechanisms they identified.The study involves the gene that produces a protein called NHE6. Mutation of the gene is directly associated with a rare and severe autism-related condition known as Christianson syndrome. But scientists, including senior author Dr. Eric Morrow, have also associated the protein with more general autism.”In generalized autism this protein is downregulated,” said Morrow, assistant professor of biology in the Department of Molecular Biology, Cellular Biology, and Biochemistry at Brown and a psychiatrist who sees autism patients at the Bradley Hospital in East Providence. “That meant to us that downregulation of NHE6 is relevant to a sizeable subset of autism.”The NHE6 protein helps to regulate acidity in the endosomes of cells. These endosomes are responsible for transporting material around cells and for degrading proteins including ones that signal neurons to grow the elaborately branched axons and dendrites that form neural connections.In their experiments the researchers measured acidity in the endosomes of brain cells of normal mice and in mice with mutations in the NHE6 gene. They found that the mutant mice had significantly higher endosome acidity. …Read more
Sep. 11, 2013 — It is hardly possible to talk about fossil insects in amber without the 1993 movie Jurassic Park entering the debate. The idea of recreating dinosaurs by extracting DNA from insects in amber has held the fascination of the public for two decades. Claims for successful extraction of DNA from amber up to 130 million-years-old by various scientists in the early 1990s were only seriously questioned when a study at the Natural History Museum, London, was unable to replicate the process. The original claims are now considered by many to be a text-book example of modern contaminant DNA in the samples. Nonetheless, some scientists hold fast to their original claims.Research just published in the journal The Public Library of Science ONE (PLOS ONE) by a team of researchers from the Faculty of Life Sciences at The University of Manchester can now confirm that the existence of DNA in amber fossils is highly unlikely. The team led by amber expert Dr David Penney and co-ordinated by ancient DNA expert Professor Terry Brown used highly-sensitive ‘next generation’ sequencing techniques — the most advance type of DNA sequencing — on insects in copal, the sub-fossilized resin precursor of amber.The research was conducted wearing full forensic suits in the dedicated ancient DNA facility at The University of Manchester, which comprises a suite of independent, physically isolated laboratories, each with an ultra-filtered air supply maintaining positive displacement pressure and a managed access system.According to Professor Brown: “In the original 1990s studies DNA amplification was achieved by a process called the polymerase chain reaction (PCR), which will preferentially amplify any modern, undamaged DNA molecules that contaminate an extract of partially degraded ancient ones to give false positive results that might be mistaken for genuine ancient DNA. Our approach, using ‘next generation’ sequencing methods is ideal for ancient DNA because it provides sequences for all the DNA molecules in an extract, regardless of their length, and is less likely to give preference to contaminating modern molecules.”The team concluded that their inability to detect ancient DNA in relatively young (60 years to 10,600 years old) sub-fossilized insects in copal, despite using sensitive next generation methods, suggests that the potential for DNA survival in resin inclusions is no better, and perhaps worse, than that in air-dried museum insects (from which DNA has been retrieved using similar techniques). This raises significant doubts about claims of DNA extraction from fossil insects in amber, many millions of years older than copal.Dr Penney said: “Intuitively, one might imagine that the complete and rapid engulfment in resin, resulting in almost instantaneous demise, might promote the preservation of DNA in a resin entombed insect, but this appears not to be the case. So, unfortunately, the Jurassic Park scenario must remain in the realms of fiction.”Read more
Sep. 11, 2013 — After a period of relative calm during the 1990s, rapid changes in American families began anew during the 2000s, a new analysis suggests.Young people delayed marriage longer than ever before, permanent singlehood increased, and divorce and remarriage continued to rise during the first decade of the century.But the most troubling finding, researchers say, may be how American families have taken divergent paths: White people, the educated and the economically secure have much more stable family situations than minorities, the uneducated and the poor.”The state of American families has become increasingly polarized,” said Zhenchao Qian, author of the new study and professor of sociology at The Ohio State University.”Race and ethnicity, education, economics and immigration status are increasingly linked to how well families fare.”Qian said the end result of the continuing changes he found in the 2000s is that “there is no longer any such thing as a typical American family.”Qian’s analysis, based on data from the 2000 U.S. Census and the 2008-2010 American Community Survey, among other sources, is contained in a new report for the US2010 Project, sponsored by the Russell Sage Foundation and Brown University.Qian said the Great Recession of the late 2000s played a large role in the changes he saw in American families during the decade covered by this study.”There is no doubt that the gap between America’s haves and have-nots grew larger than ever during the 2000s,” he said.”This gap has shaped American families in multiple ways. It influences the kind of families we live in and the kind of family environment in which we raise our children.”The recession may be a big reason why young people delayed marriage longer than ever before, with many moving back with their parents as they search for work or weather financial difficulties. In 2008-2010, 43 percent of 20- to 24-year-olds and 19 percent of 25- to 29-year-olds lived with their parents.Meanwhile, the percentage of U.S.-born women aged 20-24 who have ever been married declined from 31 percent to 19 percent between 2000 and 2008-2010. For men, the decline was from 21 percent to 11 percent.By ages 50 to 54, 13 percent of American-born men and 10 percent of women remained unmarried.Divorce and remarriage also increased during the decade. Among currently married men, the proportion who were married more than once increased from 17 percent in 1980 to 25 percent in 2008-2010. Similar results were found for women.”We’re seeing more evidence of a ‘marriage-go-round’ in which people go from marriage to divorce to remarriage, sometimes multiple times,” Qian said.But all of these results mask the important differences in family outcomes depending on race, education, immigrant status and economic status. Race was especially important.African Americans had the lowest percentage ever married at every age group, the highest proportion of permanent singlehood by ages 50-54, lower levels of cohabitation, highest divorce-to-marriage ratios, and a larger share of remarriages.”A lot of this can be linked to the poor economic circumstances of African Americans,” he said.”Unemployment, underemployment and poor economic prospects have a strong negative effect on whether people get married and stay married. African Americans are more likely than other groups to experience all of these problems.”Education also had a strong role in family life. …Read more
Sep. 9, 2013 — Those trying to lose weight are often told to not skip breakfast. A new study from the University of Alabama at Birmingham shows that while an association exists between breakfast and weight management, the question of whether eating vs. skipping breakfast affects weight has not been answered by research.Dietary Guidelines for Americans recommend eating a nutrient-dense breakfast to promote calorie balance and weight management, since not eating breakfast has been associated with excess body weight. A team led by David Allison, Ph.D., associate dean for science in the UAB School of Public Health, said that studies designed to find links between two things, like breakfast habits and obesity, often do not prove that one causes the other.Andrew Brown, Ph.D., first author of the new study recently published online in the American Journal of Clinical Nutrition, spearheaded the examination of 92 studies about the proposed effect of breakfast on obesity (PEBO). The PEBO-related research literature, the authors found, seemed to be influenced by factors that led to exaggerated beliefs and statements about the purported effects of breakfast consumption on obesity. These include research that lacks probative value and biased research reporting.Probative value is the extent to which a study can move knowledge forward from the current status quo. The authors explain that probative value of a given study on a topic tends to decrease as similar types of studies are repeated excessively.”Another way to look at it is to ask, ‘Do we really feel any more confident about the relationship between skipping breakfast and obesity after the 78th compared to the 77th cross-sectional association study,”’ Brown said.Biased research reporting, the authors explain, entails distorting research findings in ways that support a particular hypothesis beyond what the data support.”We specifically found that research articles tended to overstate the strength of study designs and ignored evidence that did not support the proposed effect of breakfast on obesity,” Brown said. “These distortions leave readers believing that the relationship between breakfast and obesity is more strongly established by science than the data actually support.”Allison and his team, which included Brown and Michelle Bohan Brown, found that scientists collectively do not know as much about the relationship between skipping breakfast and obesity as previously thought, based on the current state of PEBO-related research.Their meta-analysis indicated that there is certainty that breakfast-skipping and obesity are associated, but it cannot confirm whether there is a causal effect of skipping breakfast on obesity.”Although we know that breakfast-skippers are more likely to be overweight or obese, we do not know if making breakfast-skippers eat breakfast would decrease their weight,” Brown said. “Nor do we know if making breakfast-eaters stop eating breakfast would cause them to gain weight.””Uncertainty should not be confused with evidence of no benefit or harm, though,” Allison aid. …Read more
Sep. 4, 2013 — For nearly 15 years, biologists around the world have been watching as millions of frogs succumb to an infectious fungus called chytrid.Now a group of Wichita State University students has discovered evidence of the deadly chytrid fungus in the Wichita area. This is the first report of chytrid in Kansas.The pathogenic fungus is found in all neighboring states and has caused the decline and extinction of amphibian species globally.Wichita State’s findings are based on two years of undergraduate and graduate research as part of a field ecology class in WSU’s Department of Biology.Jameson said the research results fill a gap in the middle portion of the United States where the fungus has never been reported. The only other study conducted in Kansas was in 2007. It studied five frogs in Johnson County, none of which tested positive.The next step, Jameson said, is for the students to publish their findings in the peer-reviewed scientific journal Herpetological Review.And she hopes to spread word to the community as a whole. As with the white nose fungus in bats — which for years has been causing a severe decline in bats — education on how to prevent spreading chytrid is key.’Potential trickle-down effect’The research conducted by the group of 10 students was conducted at WSU field stations near Wichita, Viola and Waterloo.It involved catching frogs and identifying them, swabbing them in a sterile fashion and recording water quality of the surrounding habitat. In addition, there’s a molecular component of DNA extraction and amplification.It has been a community effort, Jameson said, requiring the skills and participation of many students. It also builds on the aquatic toxicology research of WSU professor Karen Brown and students in her lab.Graduate student Timothy Eberl, who conducted the DNA analyses this summer, hopes the new research will be valuable for the future of the state’s amphibian populations.”We are speaking of possible keystone species within the aquatic environments of this state, and the potential trickle-down effect may have a longer reach than even we realize.”Jameson said there are steps people can take to help prevent the spread of chytrid. Never move a frog from one lake or pond to another. Always clean wet or muddy boots and tires, and fishing, camping, gardening or frog-survey equipment. …Read more
Aug. 8, 2013 — Treatment advances have helped improve patient survival of Burkitt lymphoma, a highly aggressive cancer, but not among the elderly, patients at a late stage, or blacks. A new study, reported in the journal Cancer, uses those findings to develop a risk score that will help doctors, patients, families, and researchers better understand prognosis.A new study in the journal Cancer that tracked survival during the last decade of more than 2,200 adults with a highly aggressive form of lymphoma finds that with notable exceptions, medicine has made substantial progress in treating them successfully. To help doctors and researchers better understand who responds well to treatment and who doesn’t, the study authors used their findings to create a stratified risk score of patient prognosis.Burkitt lymphoma is not a common lymphoma but it is especially aggressive. The apparent progress doctors have made during the last two decades has come, unlike with many other cancers, with little guidance about how to treat different patients or what outcomes to expect. The same regimen of intensive chemotherapy and the monoclonal antibody rituximab are recommended for most patients.”There was little available for Burkitt lymphoma in terms of prognostic factors, indicators, or scoring,” said Dr. Jorge Castillo, assistant professor of medicine at the Warren Alpert Medical School of Brown University and a hematology/oncology specialist at Rhode Island Hospital. He is the lead author of the study, which first appeared online July 30.Castillo wanted to understand the prognosis of patients better, so he and his co-authors looked at 11 years of patient records in the Surveillance, Epidemiology, and End Results (SEER) database, which keeps patient demographic and outcomes data from 18 areas around the country. They analyzed survival rates among 2,284 patients by factors including age, race, stage of the cancer at diagnosis, and in what region of the body the cancer struck.What they found is that while survival rates have risen substantially overall, outcomes have not improved much for patients who are older than 60, black, or whose cancer is diagnosed at a late stage. They used these risk factors to create a simple new risk score that allowed them to make meaningful distinctions about prognosis. …Read more
Aug. 6, 2013 — A new analysis has found that mothers who are more extroverted and less anxious are more likely to breastfeed and to continue to breastfeed than mothers who are introverted or anxious. Published early online in the Journal of Advanced Nursing, the study indicates that new mothers with certain personalities may need additional support and education to help them feel confident, self assured, and knowledgeable about breastfeeding.Breastfeeding is important for the health of both mother and baby: breastfed babies have lower levels of infections and allergies and are less likely to be overweight, while mothers who breastfeed are less likely to develop certain cancers.Many factors can affect whether a mother breastfeeds, but mothers who have lots of support, feel confident, and know how to overcome problems are more likely to breastfeed for longer. Understanding what makes a mother feel confident and supported is important to increasing breastfeeding rates. Many studies have looked at the role of mothers’ education, age, and relationships, but the link between breastfeeding and a mother’s personality has not been explored.To investigate, Amy Brown, PhD, of Swansea University in the United Kingdom, surveyed 602 mothers with infants aged six to 12 months old. The questionnaire examined the mothers’ personalities, how long they breastfed, and their attitudes and experiences of breastfeeding. Data were collected between March and June 2009.Mothers who indicated that they were extroverts and were emotionally stable were significantly more likely to initiate and continue breastfeeding for a longer duration. Mothers who were introverted or anxious were more likely to use formula milk or only breastfeed for a short while.Dr. Brown believes that the findings can be explained by the link between mothers’ personalities and their attitudes and experiences of breastfeeding. Mothers who were introverted felt more self-conscious about breastfeeding in front of others and were more likely to formula feed because other people wanted them to. …Read more
June 27, 2013 — For protein-based drugs such as insulin to be taken orally rather than injected, bioengineers need to find a way to shuttle them safely through the stomach to the small intestine where they can be absorbed and distributed by the bloodstream. Progress has been slow, but in a new study, researchers report an important technological advance: They show that a “bioadhesive” coating significantly increased the intestinal uptake of polymer nanoparticles in rats and that the nanoparticles were delivered to tissues around the body in a way that could potentially be controlled.”The results of these studies provide strong support for the use of bioadhesive polymers to enhance nano- and microparticle uptake from the small intestine for oral drug delivery,” wrote the researchers in the Journal of Controlled Release, led by corresponding author Edith Mathiowitz, professor of medical science at Brown University.Mathiowitz, who teaches in Brown’s Department of Molecular Pharmacology, Physiology, and Biotechnology, has been working for more than a decade to develop bioadhesive coatings that can get nanoparticles to stick to the mucosal lining of the intestine so that they will be taken up into its epithelial cells and transferred into the bloodstream. The idea is that protein-based medicines would be carried in the nanoparticles.In the new study, which appeared online June 21, Mathiowitz put one of her most promising coatings, a chemical called PBMAD, to the test both on the lab bench and in animal models. Mathiowitz and her colleagues have applied for a patent related to the work, which would be assigned to Brown University.In prior experiments, Mathiowitz and her group have shown not only that PBMAD has bioadhesive properties, but also that it withstands the acidic environment of the stomach and then dissolves in the higher pH of the small intestine.Adhere, absorb, arriveThe newly published results focused on the question of how many particles, whether coated with PBMAD or not, would be taken up by the intestine and distributed to tissues. For easier tracking throughout the body, Mathiowitz’s team purposely used experimental and control particles made of materials that the body would not break down. Because they were “non-erodible” the particles did not carry any medicine.The researchers used particles about 500 nanometers in diameter made of two different materials: polystyrene, which adheres pretty well to the intestine’s mucosal lining, and another plastic called PMMA, that does not. They coated some of the PMMA particles in PBMAD, to see if the bioadhesive coating could get PMMA particles to stick more reliably to the intestine and then get absorbed.First the team, including authors Joshua Reineke of Wayne State University and Daniel Cho of Brown, performed basic benchtop tests to see how well each kind of particles adhered. The PBMAD-coated particles proved to have the strongest stickiness to intestinal tissue, binding more than twice as strongly as the uncoated PMMA particles and about 1.5 times as strongly as the polystyrene particles.The main experiment, however, involved injecting doses of the different particles into the intestines of rats to see whether they would be absorbed and where those that were taken up could be found five hours later. Some rats got a dose of the polystyrene particles, some got the uncoated PMMA and some got the PBMAD-coated PMMA particles.Measurements showed that the rats absorbed 66.9 percent of the PBMAD-coated particles, 45.8 percent of the polystyrene particles and only 1.9 percent of the uncoated PMMA partcles.Meanwhile, the different particles had very different distribution profiles around the body. More than 80 percent of the polystyrene particles that were absorbed went to the liver and another 10 percent went to the kidneys. …Read more
June 17, 2013 — A type of drug normally used to treat heart failure and high blood pressure helped prevent weight gain and other complications related to a high-fat diet in an animal study.The results were presented today at The Endocrine Society’s 95th Annual Meeting in San Francisco.Weight gain, especially around the waist, and high blood pressure, combine with other abnormalities to form a cluster of diseases known as metabolic syndrome, which increases the risk of heart disease, diabetes and other serious illnesses. With obesity rates climbing in developed countries throughout the world, medical researchers are trying to find new drugs to prevent metabolic syndrome from occurring.One new and promising approach involves blocking the action of aldosterone and glucocorticoids, hormones synthesized in the adrenal cortex of mammals. These hormones are capable of activating the mineralocorticoid receptors (MRs). MRs are ligand-activated transcription factors that play a key role in many physiological and pathological processes occurring in several tissues and organs, including kidney, heart and adipose tissue.Drugs that prevent MRs from reacting to their ligands are known as MR antagonists. In this study, investigators examined, in mice fed a high-fat diet, the effects of drospirenone and spironolactone, two MR antagonists currently used in clinical practice that have been previously shown to modulate adipocyte differentiation in vitro. They found that the drugs had several benefits, including helping to prevent weight gain and to increase the number of energy-burning fat cells. Animals that received MR antagonists combined with a high-fat diet exhibited more brown fat cells interspersed within white fat tissue, compared to untreated controls. The so-called good kind of fat, brown fat cells actually burn energy to help prevent weight gain, while white fat does the opposite, storing energy as more fat cells.In order to evaluate the expansion of brown adipose tissue, the investigators also used special imaging tests to measure the percentage of water in fat cells which, at high levels, indicates the presence of brown fat.In addition, these MR antagonists were effective in reducing the high levels of blood glucose related to impaired glucose tolerance, which can be a precursor to diabetes.”These data open new unexpected applications of MR antagonists in the treatment of obesity and its metabolic complications, since their use in animal models reverses the metabolic dysfunction induced by a high-fat diet, promoting the activation of brown-like fat in classical white fat depots,” said study lead author Andrea Armani, Ph.D., a post-doctoral fellow in obesity research. “Indeed, MR antagonism has promise as a novel approach to treat metabolic syndrome.”The study was coordinated by Massimiliano Caprio, MD, PhD, at the IRCCS San Raffaele Pisana Research Center in Rome, Italy. Previous research by Dr. …Read more
June 11, 2013 — The first complete chemical analysis of feathers from Archaeopteryx, a famous fossil linking dinosaurs and birds, reveals that the feathers of this early bird were patterned – light in colour, with a dark edge and tip to the feather - rather than all black, as previously thought.The findings came from X-ray experiments undertaken by a team from the University of Manchester, working with colleagues at the US Department of Energy’s (DOE) SLAC National Accelerator Laboratory. The scientists were able to find chemical traces of the original ‘dinobird’ and dilute traces of plumage pigments in the 150 million-year-old fossil.”This is a big leap forward in our understanding of the evolution of plumage and also the preservation of feathers,” said Dr Phil Manning, a palaeontologist at The University of Manchester and lead author of the report in the June 13 issue of the Journal of Analytical Atomic Spectrometry (Royal Society of Chemistry).Only 11 specimens of Archaeopteryx have been found, the first one consisting of a single feather. Until a few years ago, researchers thought minerals would have replaced all the bones and tissues of the original animal during fossilisation, leaving no chemical traces behind, but two recently developed methods have turned up more information about the dinobird and its plumage.The first is the discovery of melanosomes – microscopic ‘biological paint pot’ structures in which pigment was once made, but are still visible in some rare fossil feathers. A team led by researchers at Brown University announced last year that an analysis of melanosomes in the single Archaeopteryx feather indicated it was black. They identified the feather as a covert – a type of feather that covers the primary and secondary wing feathers – and said its heavy pigmentation may have strengthened it against the wear and tear of flight, as it does in modern birds.However, that study examined melanosomes from just a few locations in the fossilised feather, explained SLAC’s Dr Uwe Bergmann: “It’s actually quite a beautiful paper,” he said, “but they took just tiny samples of the feather, not the whole thing.”The second is a method that Drs Bergmann, Manning and Roy Wogelius have developed for rapidly scanning entire fossils and analysing their chemistry with an X-ray beam at SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL) in the USA.Over the past three years, the team used this method to discover chemical traces locked in the dinobird’s bones, feathers and in the surrounding rock, as well as pigments from the fossilised feathers of two specimens of another species of early bird. This allowed the team to recreate the plumage pattern of an extinct bird for the very first time.In the latest study, the team scanned the entire fossil of the first Archaeopteryx feather with the SSRL X-ray beam. They found trace-metals that have been shown to be associated with pigment and organic sulphur compounds that could only have come from the animal’s original feathers.”The fact that these compounds have been preserved in-place for 150 million years is extraordinary,” said Dr Manning said. “Together, these chemical traces show that the feather was light in colour with areas of darker pigment along one edge and on the tip.”Scans of a second fossilised Archaeopteryx, known as the Berlin counterpart, also show that the trace-metal inventory supported the same plumage pigmentation pattern.”Co-author Dr Roy Wogelius, also based in Manchester’s School of Earth, Atmospheric and Environmental Sciences, said: “This work refines our understanding of pigment patterning in perhaps the most important known fossil. Our technique shows that complex patterns were present even at the very earliest steps in the evolution of birds.”The team’s results show that the chemical analysis provided by synchrotron X-ray sources, such as SSRL, is crucial when studying the fossil remains of such pivotal species. The plumage patterns can begin to help scientists review their possible role in the courtship, reproduction and evolution of birds and possibly shed new light on their health, eating habits and environment.Dr Manning added: “It is remarkable that x-rays brighter than a million suns can shed new light on our understanding of the processes that have locked elements in place for such vast periods of time. …Read more
May 1, 2013 — Amphibian populations living close to agricultural fields have become more resistant to a common insecticide and are actually resistant to multiple common insecticides, according to two recent studies conducted at the University of Pittsburgh.Amphibian populations living close to agricultural fields have become more resistant to a common insecticide and are actually resistant to multiple common insecticides.
In a study published today in Evolutionary Applications, the Pitt researchers demonstrate, for the first time, that tadpoles from populations close to farm fields are more resistant to chlorpyrifos — one of the most commonly applied insecticides in the world, often sold as “Dursban” or “Lorsban.” In addition, a related study published in February shows that tadpoles resistant to chlorpyrifos are also resistant to other insecticides.
“While we’ve made a lot of progress in understanding the ecological consequences to animals that are unintentionally exposed to insecticides, the evolutionary consequences are poorly understood,” said study principal investigator Rick Relyea, Pitt professor of biological sciences and director of the University’s Pymatuning Laboratory of Ecology. “Our study is the first to explore how amphibian populations might evolve to be resistant to insecticides when they live in places that have been sprayed for many years.”
The Pitt researchers used newly hatched tadpoles collected from nine populations of wood frogs living at different distances from agricultural fields. They tested the frogs’ resistance when exposed to chlorpyrifos, which is used against insects, and Roundup Original MAX®, which is a common herbicide used against weeds.
Relyea and his Pitt collaborators exposed the tadpoles from each of the nine populations to environments containing either no pesticides, chlorpyrifos, or Roundup®. After 48 hours, they measured how well the populations survived.
“Wood frogs living close to agricultural land were more likely to have been exposed to pesticides for many generations compared to those living far from agriculture; the latter frog populations likely experienced little or no exposure to pesticides,” said Rickey Cothran, the lead author of the study and a postdoctoral researcher in Relyea’s lab. “Although populations differed in their resistance to Roundup®, populations closer to fields were not more resistant to the herbicide.”Wood frogs living close to agricultural land were more likely to have been exposed to pesticides for many generations compared to those living far from agriculture.
“Because chlorpyrifos kills in a way that is similar to many other insecticides, higher resistance may have been favored each time any insecticide was sprayed,” said Pitt alumnus Jenise Brown (A&S ’09), a coauthor of the study and a former undergraduate researcher in Relyea’s lab. “In contrast, herbicides have a variety of ways that they kill organisms, which may make it harder for animals to be resistant when exposed to different herbicides over many years.”
In a related study, published online Feb. 21 in Environmental Toxicology and Chemistry, Relyea’s Pitt research team examined whether wood frog populations that were resistant to chlorpyrifos might also be resistant to other insecticides. This phenomenon, said Relyea, happens commonly in pest species when farmers switch pesticides from year to year, but little is known about how this switching of pesticides affects amphibians.
Using three commonly applied pesticides that have similar chemical properties — chlorpyrifos, carbaryl, and malathion — the Pitt researchers exposed 15 populations of wood frog tadpoles to high concentrations of each insecticide. They found that wood frog populations with resistance to one insecticide also had resistance to the other insecticides.
“This has a beneficial outcome,” said Jessica Hua, the lead author of the second study and a graduate student in Relyea’s lab. “While it doesn’t mean that pesticides are beneficial to amphibians, our work does suggest that amphibians can evolve to resist a variety of pesticides and therefore improve their survival.”
As they hypothesized in the study published today, the researchers suspect that the reason for this cross-resistance is that chlorpyrifos kills in a way that is similar to many other insecticides. Thus, evolving higher resistance to one insecticide may provide higher resistance to others.
“This finding may buffer an amphibian population from suffering the consequences of exposures to new, but similar-acting chemicals,” said Aaron Stoler, a coauthor of the second paper and a graduate student in Relyea’s lab.
In the future, Relyea and his team plan to study the genetic mechanisms that underlie increased resistance in amphibians and determine whether increased resistance occurs in additional animal species that are not the targets of pesticides.
The article published today in Evolutionary Applications is titled “Proximity to agriculture is correlated with pesticide tolerance: Evidence for the evolution of amphibian resistance to modern pesticides.” The article published Feb. 21 in Environmental Toxicology and Chemistry is titled “Cross-tolerance in amphibians: Wood frog mortality when exposed to three insecticides with a common mode of action.”
Funding for both studies was provided by a National Science Foundation grant to Relyea. Funding for the second study was also provided by Pitt’s G. Murray McKinley Research Fund to Hua and Stoler. The experiments were conducted at Pitt’s Pymatuning Laboratory of Ecology from 2009 to 2012.Read more
Jan. 10, 2013 — Herbal and complementary medicines could be recommended as an alternative to hormone replacement therapy (HRT) for treating postmenopausal symptoms says a new review published January 11 in The Obstetrician and Gynaecologist (TOG).
The review outlines the advantages and limitations of both pharmacological and herbal and complementary treatments for women with postmenopausal symptoms.
The menopause is defined as the time after a woman’s menstrual periods have ceased (12 months after a woman’s final menstrual period). It is associated with an estrogen deficiency and can cause an increase in vasomotor symptoms (hot flushes), genitourinary symptoms (vaginal dryness, sexual dysfunction, frequent urinary tract infections, urinary incontinence), and musculoskeletal symptoms (joint pain) as well as sleep and mood disturbance.
One of the most common menopausal symptoms is hot flushes; approximately two-thirds of postmenopausal women will experience them, and 20% of women can experience them for up to 15 years, states the review.
Estrogen deficiency can also lead to longer-term health issues such as cardiovascular disease and osteoporosis. While pharmacological agents are available to treat postmenopausal symptoms, many non-pharmacological treatment options are also available.
HRT is the most effective treatment of hot flushes, improving symptoms in 80 — 90% of women, says the review. However, the author notes that there are possible health risks associated with HRT, such as links to breast cancer, blood clots, stroke, and cardiovascular problems.
Due to these possible risks, other treatment options may be equally effective, such as behaviour modification and herbal and complimentary medicines, says the author.
The review states that as many as 50 — 75% of postmenopausal women use herbal options to treat hot flushes, and of the complimentary therapies, soy, red clover and black cohosh have been the most investigated.
Soy is the most common plant containing estrogen, found naturally in food and supplements. Previous research has shown a reduction in hot flush symptoms with soy ranging from 20 — 55%. Red clover, a legume also containing estrogen, and black cohosh, a plant originating from the eastern United States and Canada, have also been reported to ease postmenopausal symptoms.
The author of the review recommends these herbal treatments as there are no significant adverse side effects associated with them, as long as they are used in women who do not have a personal history of breast cancer, are not at high risk for breast cancer, and are not taking tamoxifen. However, the review notes that herbal medicines are not regulated in many countries, and therefore the contents of a given product may vary from sample to sample.
Iris Tong, Director of Women’s Primary Care at the Women’s Medicine Collaborative, The Warren Alpert Medical School of Brown University, Rhode Island, and author of the review said:
“Up to 75% of women use herbal and complimentary medicines to treat their postmenopausal symptoms. Therefore, it is vitally important for healthcare providers to be aware of and informed about the non-pharmacological therapies available for women who are experiencing postmenopausal symptoms and who are looking for an alternative to HRT.”
TOG‘s Editor -in-Chief, Jason Waugh said:
“Postmenopausal symptoms can be very distressing and it is important to review the advantages and limitations of the non-pharmacological treatments available as well as the pharmacological ones. Even simple behaviour modification can make a difference to postmenopausal symptoms, including keeping the room temperature cool, wearing layered clothing, relaxation techniques and smoking cessation.”Read more