Breakthrough drug-eluting patch stops scar growth, reduces scar tissues

Scars — in particular keloid scars that result from overgrowth of skin tissue after injuries or surgeries — are unsightly and can even lead to disfigurement and psychological problems of affected patients. Individuals with darker pigmentation — in particular people with African, Hispanic or South-Asian genetic background — are more likely to develop this skin tissue disorder. Current therapy options, including surgery and injections of corticosteroids into scar tissues, are often ineffective, require clinical supervision and can be costly.A new invention by researchers from Nanyang Technological University in Singapore (reported in the current issue of TECHNOLOGY) provides a simple, affordable and — most importantly — highly effective way for patients to self-treat keloid scars. The team of scientists and engineers from NTU’s School of Chemical and Biomedical Engineering, in collaboration with clinicians from Singapore’s National Skin Centre, have developed a special patch made from polymers fabricated into microneedles, which are loaded with the US food and drug administration (FDA)-approved scar-reducing drug, 5-fluorouracil. Self-administered by patients, the microneedles attach the patch to scar tissue and allow sustained drug-release (one patch per night). The drug as well as the physical contact of the microneedles with the scar tissue contributes to the efficacy of the device, leading to the cessation of scar tissue growth and a considerable reduction of keloids as demonstrated in laboratory cultures and experiments with animals. “Most patients seek treatment due to disfigurement and/or pain or itch of scars,” says Assistant Professor Xu Chenjie from NTU who leads the study. “We wanted to develop a simple, convenient, and cost-effective device able to inhibit keloid growth in skin tissue and reduce the size of disfiguring scars,” adds Yuejun Kang, another key investigator in the study from NTU.”Self-administered treatment for keloid scars can reduce the economic burden on the healthcare system and provide a treatment option for patients who have limited access to medical care,” comments Professor Jeffrey Karp from Brigham and Women’s Hospital at Harvard Medical School, US, an expert on medical device design who was not involved in this study.Story Source:The above story is based on materials provided by World Scientific. Note: Materials may be edited for content and length.

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Ancient nomads spread earliest domestic grains along Silk Road: Findings push back earliest known East-West interaction by 2,000 years

Charred grains of barley, millet and wheat deposited nearly 5,000 years ago at campsites in the high plains of Kazakhstan show that nomadic sheepherders played a surprisingly important role in the early spread of domesticated crops throughout a mountainous east-west corridor along the historic Silk Road, suggests new research from Washington University in St. Louis.”Our findings indicate that ancient nomadic pastoralists were key players in an east-west network that linked innovations and commodities between present-day China and southwest Asia,” said study co-author Michael Frachetti, PhD, an associate professor of archaeology in Arts & Sciences at Washington University and principal investigator on the research project.”Ancient wheat and broomcorn millet, recovered in nomadic campsites in Kazakhstan, show that prehistoric herders in Central Eurasia had incorporated both regional crops into their economy and rituals nearly 5,000 years ago, pushing back the chronology of interaction along the territory of the ‘Silk Road’ more than 2,000 years,” Frachetti said.The study, to be published April 2 in the Proceedings of the Royal Society B, establishes that several strains of ancient grains and peas had made their way across Eurasia thousands of years earlier than previously documented.While these crops have been known to exist much earlier in ancient China and Southwest Asia, finding them intermingled in the Bronze Age burials and households of nomadic pastoralists provides some of the earliest concrete signs for east-west interaction in the vast expanse of Eurasian mountains and the first botanical evidence for farming among Bronze Age nomads.Bread wheat, cultivated at least 6,000 years ago in Southwest Asia, was absent in China before 2500 B.C. while broomcorn millet, domesticated 8,000 years ago in China, is missing in southwest Asia before 2000 B.C. This study documents that ancient grains from eastern China and soutwest Asia had made their way to Kazakhstan in the center of the continent by 2700-2500 B.C. (nearly 5,000 years ago).”This study starts to rewrite the model for economic change across Eurasia,” said first author Robert Spengler, PhD, a paleoethnobotanist and research associate in Arts & Sciences at WUSTL.”It illustrates that nomads had diverse economic systems and were important for reshaping economic spheres more generally.”Findings are based on archaeobotanical data collected from four Bronze Age pastoralist campsites in Central Eurasian steppe/mountains: Tasbas and Begash in the highlands of Kazakhstan and Ojakly and Site 1211/1219 in Turkmenistan.”This is one of the first systematic applications of archaeobotany in the region, making the potential for further future discovery very exciting,” Spengler said.Frachetti and a team of WUSTL researchers led the on-site excavations, working closely with archaeologists based in Turkmenistan, Kazakhstan and Italy. Spengler conducted the paleoethnobotany laboratory work at WUSTL, under the directorship of Gayle J. Fritz, PhD, professor of archaeology and expert in human-plant relationships.”Finding this diverse crop assemblage at Tasbas and Begash illustrates first evidence for the westward spread of East Asian and Southwest Asian crops eastward, and the surprise is that it is nomads who are the agents of change,” Frachetti said.Story Source:The above story is based on materials provided by Washington University in St. Louis. The original article was written by Gerry Everding. Note: Materials may be edited for content and length.

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Coffee Consumption Reduces Mortality Risk from Liver Cirrhosis

New research reveals that consuming two or more cups of coffee each day reduces the risk of death from liver cirrhosis by 66%, specifically cirrhosis caused by non-viral hepatitis. Findings in Hepatology, a journal published by Wiley on behalf of the American Association for the Study of Liver Diseases, show that tea, fruit juice, and soft drink consumption are not linked to cirrhosis mortality risk. As with previous studies heavy alcohol use was found to increase risk of death from cirrhosis.A 2004 report from The World Health Organization (WHO) estimates that each year 1.3% of total death worldwide is caused by liver cirrhosis. Previous research shows that 29 million Europeans have chronic liver disease, with 17,000 deaths annually attributed to cirrhosis. Further WHO reports state that liver cirrhosis is the 11th leading cause of death in the U.S.”Prior evidence suggests that coffee may reduce liver damage in patients with chronic liver disease,” said lead researcher, Dr. Woon-Puay Koh with Duke-NUS Graduate Medical School Singapore and the National University of Singapore. “Our study examined the effects of consuming coffee, alcohol, black tea, green tea, and soft drinks on risk of mortality from cirrhosis.”This prospective population-based study, known as The Singapore Chinese Health Study, recruited 63,275 Chinese subjects between the ages of 45 and 74 living in Singapore. Participants provided information on diet, lifestyle choices, and medical history during in-person interviews conducted between 1993 and 1998. Patients were followed for an average of nearly 15 years, during which time there were 14,928 deaths (24%); 114 of them died from liver cirrhosis. The mean age of death was 67 years.Findings indicate that those who drank at least 20 g of ethanol daily had a greater risk of cirrhosis mortality compared to non-drinker. …

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Asian elephants reassure others in distress: First empirical evidence of consolation in elephants

Asian elephants console others who are in distress, using physical touches and vocalizations, finds a study to be published in the open access journal PeerJ. The findings are the first empirical evidence of consolation in elephants, says lead author Joshua Plotnik, who began the research as a graduate student of psychology at Emory University.”For centuries, people have observed that elephants seem to be highly intelligent and empathic animals, but as scientists we need to actually test it,” he says.Consolation behavior is rare in the animal kingdom, with empirical evidence previously provided only for the great apes, canines and certain corvids.”With their strong social bonds, it’s not surprising that elephants show concern for others,” says co-author Frans de Waal, an Emory professor of psychology and director of Living Links at Emory’s Yerkes National Primate Research Center. “This study demonstrates that elephants get distressed when they see others in distress, reaching out to calm them down, not unlike the way chimpanzees or humans embrace someone who is upset.”Plotnik received his Ph.D. from Emory in 2010 and is currently a lecturer in conservation biology at Mahidol University in Thailand and CEO of Think Elephants International, a non-profit focused on education and conservation. His main research interest is convergent cognitive evolution: The independent evolution of similar features of intelligence in species of different lineages.While Plotnik was still at Emory, he and de Waal provided evidence that elephants can both recognize themselves in a mirror — a test of self-awareness passed only by some apes, dolphins and magpies — and problem-solve cooperatively.”Humans are unique in many ways, but not in as many ways as we once thought,” Plotnik says.The current study focused on a group of 26 captive Asian elephants spread over about 30 acres at an elephant camp in northern Thailand. For nearly a year, the researchers observed and recorded incidents when an elephant displayed a stress reaction, and the responses from other nearby elephants.The initial stress responses came from either unobservable, or obvious, stimuli: Events such as a dog walking past, a snake or other potentially dangerous animal rustling the grass, or the presence of another, unfriendly elephant. “When an elephant gets spooked, its ears go out, its tail stands erect or curls out, and it may emit a low-frequency rumble, trumpet and roar to signal its distress,” Plotnik says.The study found that nearby elephants affiliated significantly more with a distressed individual through directed, physical contact following a stress event than during control periods. As a typical example, a nearby elephant would go to the side of the distressed animal and use its trunk to gently touch its face, or put its trunk in the other animal’s mouth.The gesture of putting their trunks in each other’s mouths is almost like an elephant handshake or hug, Plotnik says. “It’s a very vulnerable position to put yourself in, because you could get bitten. It may be sending a signal of, ‘I’m here to help you, not hurt you.'”The responding elephants also showed a tendency to vocalize. …

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Seven new genetic regions linked to type 2 diabetes

Seven new genetic regions associated with type 2 diabetes have been identified in the largest study to date of the genetic basis of the disease.DNA data was brought together from more than 48,000 patients and 139,000 healthy controls from four different ethnic groups. The research was conducted by an international consortium of investigators from 20 countries on four continents, co-led by investigators from Oxford University’s Wellcome Trust Centre for Human Genetics.The majority of such ‘genome-wide association studies’ have been done in populations with European backgrounds. This research is notable for including DNA data from populations of Asian and Hispanic origin as well.The researchers believe that, as more genetic data increasingly become available from populations of South Asian ancestry and, particularly, African descent, it will be possible to map genes implicated in type 2 diabetes ever more closely.’One of the striking features of these data is how much of the genetic variation that influences diabetes is shared between major ethnic groups,’ says Wellcome Trust Senior Investigator Professor Mark McCarthy from the University of Oxford. ‘This has allowed us to combine data from more than 50 studies from across the globe to discover new genetic regions affecting risk of diabetes.’He adds: ‘The overlap in signals between populations of European, Asian and Hispanic origin argues that the risk regions we have found to date do not explain the clear differences in the patterns of diabetes between those groups.’Among the regions identified by the international research team are two, near the genes ARL15 and RREB1, that also show strong links to elevated levels of insulin and glucose in the body — two key characteristics of type 2 diabetes. This finding provides insights into the ways basic biochemical processes are involved in the risk of type 2 diabetes, the scientists say.The genome-wide association study looked at more than 3 million DNA variants to identify those that have a measurable impact on risk of type 2 diabetes. By combining DNA data from many tens of thousands of individuals, the consortium was able to detect, for the first time, regions where the effects on diabetes susceptibility are rather subtle.’Although the genetic effects may be small, each signal tells us something new about the biology of the disease,’ says first author Dr Anubha Mahajan of Oxford University. ‘These findings may lead us to new ways of thinking about the disease, with the aim ultimately of developing novel therapies to treat and prevent diabetes. There’s every reason to expect that drugs acting on these biological processes would have a far larger impact on an individual’s diabetes than the genetic effects we have discovered.’Principal investigator Dr Andrew Morris, also of the Wellcome Trust Centre for Human Genetics at Oxford University, says: ‘The findings of our study should also be relevant to other common human diseases. By combining genetic data from different ethnic groups, we would expect also to be able identify new DNA variants influencing risk of heart disease and some forms of cancer, for example, which are shared across ethnic groups. It has the potential to have a major impact on global public health.’Story Source:The above story is based on materials provided by University of Oxford. …

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A holistic approach catches eye disease early

Oct. 11, 2013 — An automated assessment of multiple datasets using artificial intelligence accurately diagnoses a common cause of blindness.Pathological myopia is a condition characterized by severe, progressive nearsightedness caused by the protrusion of pigmented tissue from the back of the eye. The disease is one of the leading causes of blindness worldwide and the leading cause in Asian countries. Early diagnosis is essential for preventing permanent loss of vision but heavily relies on manual screening and involves a complete eye exam, which can take up to an hour.Zhuo Zhang of the A*STAR Institute for Infocomm Research in Singapore and her colleagues have now developed an automated, computer-assisted informatics method that uses artificial intelligence to diagnose the condition accurately.In earlier work, Zhang and her colleagues developed an algorithm that could extract information about tissue texture from biomedical images of the back of the eye, or fundus, and use it to detect pathological myopia with an accuracy of 87.5%. They then showed that combining the images with demographic data such as age, sex and ethnicity, improved the accuracy further.The latest automated method — Pathological Myopia diagnosis through Biomedical and Image Informatics (PM-BMII) — takes the process one step further; it uses an artificial intelligence approach known as multiple kernel learning to fuse the demographic data and clinical fundus images with genomic information and then analyze the combined datasets.Zhang and her colleagues tested the method on data collected from 2,258 patients, 58 of whom had already been diagnosed with pathological myopia. They found that the method could detect the condition with a high degree of accuracy and that the combination of all three datasets was more accurate than any one alone or any two combined.Combining the three datasets probably produced the best results because each set contains different information that complements the other sets, therefore providing a holistic assessment of the disease.The researchers suggest that the method could also be applied to the detection of other eye diseases, “including age-related macular degeneration and glaucoma. These diseases have common characteristics,” says Zhang. “They result from both environmental and genetic risk factors, and can be observed from fundus images.”Zhang adds that it is still unclear whether adding additional types of data to the analyses would improve the accuracy of the diagnoses. “More types of data may introduce complexity into the computational model, so we cannot draw the conclusion that accuracy would be improved without further investigation.”

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Simian foamy viruses readily occur between humans and macaques in urban Bangladesh

Sep. 4, 2013 — Throughout Asia, humans and monkeys live side-by side in many urban areas. An international research team from the University of Washington, Fred Hutchinson Cancer Research Center and Jahangirnagar University has been examining transmission of a virus from monkeys to humans in Bangladesh, one of the world’s most densely populated countries. The scientists have found that some people in these urban areas are concurrently infected with multiple strains of simian foamy virus (SFV), including strains from more than one source (recombinant) that researchers originally detected in the monkeys.Simian foamy viruses, which are ubiquitous in nonhuman primates, are retroviruses like HIV. Retroviruses are shown to exhibit high levels of mutation and recombination — a potentially explosive combination.Their paper, “Zoonotic simian foamy virus in Bangladesh reflects diverse patterns of transmission and co-infection” published in the Sept. 4 issue of Emerging Microbes and Infections (EMI), characterizes the simian retroviral strains that are being zoonotically transmitted and provides a glimpse into the behaviors of humans and monkeys contributing to the infections.By analyzing what is happening at the human-primate interface, the researchers hope to protect humans from another deadly outbreak like HIV. Their focus is in Asia because it is a continent that has witnessed the emergence of several infectious diseases in the past decade. Asia also has a volatile combination of an increasingly mobile and immunocompromised population living in proximity with animals.Since more humans have been shown to have been infected with SFV through primate contact than with any other simian-borne virus, the researchers reason that pinpointing the factors that influence SFV transmission and infection are important to a general understanding of how viruses can jump the species barrier.”If we want to understand how, where and why these primate viruses are being transmitted, we need to be looking at SFV in Asia where millions of people and tens of thousands of macaques are interacting everyday and where we estimate that thousands of people could be infected with strains of SFV,” said Lisa Jones-Engel, a primatologist with the National Primate Research Center at the University of Washington and the project leader. “These Asian rhesus macaques are Darwinian superstars. They are very responsive to change and, unlike many other species of primates, they are going to continue to thrive in human-altered habitats.”Jones-Engel said if researchers had been on the ground 50 years ago, they may have seen how simian immunodeficiency viruses (SIV) crossed the species barrier resulting in HIV.”We have been playing catch up with the SIV-HIV question for years,” she said. …

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Love and work don’t always work for working class in America, study shows

Aug. 13, 2013 — The decline and disappearance of stable, unionized full-time jobs with health insurance and pensions for people who lack a college degree has had profound effects on working-class Americans who now are less likely to get married, stay married, and have their children within marriage than those with college degrees, a new University of Virginia and Harvard University study has found.The research, “Intimate Inequalities: Love and Work in a Post-Industrial Landscape,” will be presented at the 108th Annual Meeting of the American Sociological Association.”Working-class people with insecure work and few resources, little stability, and no ability to plan for a foreseeable future become concerned with their own survival and often become unable to imagine being able to provide materially and emotionally for others,” said Sarah Corse, an associate professor of sociology in U.Va.’s College of Arts & Sciences and the study’s lead author. “Insecure work changes peoples’ non-work lives.”The study was conducted through direct interviews and surveys with more than 300 working- and middle-class men and women in the U.S. The study participants were white, African-American, Asian, and Latino, between the ages of 18 and 70, and with a range of educational histories. They were married, single, divorced, cohabitating, and widowed, as well as non-parents and biological and adoptive parents.The researchers found, generally, that educated middle-class workers are better able to recover from the destabilizing effects of insecure work than the working class, and therefore can seek and find stability in relationships.”Marriage is becoming a distinctive social institution marking middle-class status,” Corse said.People who are living in an unsecure and unstable situation have difficulty being trustful of possible partners because of the risk of betrayal, noted Harvard sociologist Jennifer Silva, Corse’s co-investigator, who earned her sociology Ph.D. at U.Va. They also find it difficult to meet material or financial obligations and may feel that the emotional and psychological commitment required by marriage is too great a demand on top of other challenges.”Marriage has lost its relevance as a marker of adulthood,” said Silva, author of the book, Coming Up Short: Working Class Adulthood in an Age of Uncertainty, to be published in August by Oxford University Press.People with college degrees, however, tend to work in stable jobs with better incomes allowing for the emotional and material commitment of marriage and having children within marriage. Middle- and upper-middle class people, as a result, express high expectations for their marriages, centering on self-fulfillment, deeply engaged parenting by both parents, and psycho-emotional awareness. They also “insure” themselves against marital complacency, conflict, and dissolution through private material and emotional “investments,” such as therapy and special “date nights,” Corse said.According to Corse and Silva, wages for the non-college-educated have fallen dramatically in the United States as manufacturing work has been outsourced to other countries, greatly reducing the number of high-paying union jobs with good benefits.Increasingly, the jobs available to those without a college degree are service-sector jobs, many of which are short-term and/or part-time and lack benefits, they said.”These are foundational changes in the labor market for the working class and they broadly affect people’s lives,” they said. “Our interviewees without college degrees expressed feelings of distrust and even fear about intimate relationships, and had difficulty imagining being able to provide for others.”College-educated middle-class workers, with material, cultural, and intellectual resources, are more resilient, however, when faced with the effects of possible insecure work in tough times, and therefore are more able to commit to marriage and to planning families.

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Extinctions of large animals sever the Earth’s ‘nutrient arteries’

Aug. 13, 2013 — A new study has demonstrated that large animals have acted as carriers of key nutrients to plants and animals over thousands of years and on continental scales.The paper in the advance online publication of the journal Nature Geoscience explains that vital nutrients are contained in the dung and bodies of big animals. As they eat and move more than small animals, they have a particularly important role in transporting nutrients into areas where the soil is otherwise infertile.In the study, the researchers use a new mathematical model to calculate the effect of mass extinctions of big animals around 12,000 years ago, focusing on a case study of the Amazon forest. They estimate that extinctions back then reduced the dispersal of phosphorus in the Amazon by 98%, with far-reaching environmental consequences that remain to this day. The model also enables them to forecast the likely environmental effects of the extinction of large animals currently under threat in Africa and Asian forests.Up until 12,000 years ago, much of the world looked like an African savannah. For instance, South America was teeming with large animals, described by scientists as ‘megafauna’ — a term for animals with a body mass of more than 44kg (the size of a large dog). These megafauna in South America, which overlapped with the earliest humans, included several species of elephant-like creatures, giant ground sloths, and armadillo-like creatures the size of a small car. In South America, most nutrients originate in the Andes mountain range and are washed into the forests through the river system. However, on dry land, these nutrients are in short supply unless they are transported through animal dung and bodies. While small animals distribute nutrients over small distances, large animals have a much greater range. …

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People prefer products that help them ‘save face’ in embarrassing moments

Aug. 13, 2013 — People who are feeling embarrassed are more likely to choose items that hide or ‘repair’ the face, according to new research published in Psychological Science, a journal of the Association for Psychological Science. The research indicates that feelings of embarrassment can be alleviated by using so-called ‘restorative’ products — effectively helping people to “save face.””Previous research on embarrassment mainly documents that embarrassed individuals are motivated to avoid public exposure,” explains Ping Dong, a doctoral student at the University of Toronto and lead author of the new research. “However, little work has been done to examine how they could cope with embarrassment.”Dong and colleagues Xun (Irene) Huang of Sun Yat-Sen University and Robert S. Wyer, Jr. of the Chinese University of Hong Kong hypothesized that metaphorical reasoning — the idea of “saving face” — might be one tool for coping with embarrassment, a common negative emotion.In their first experiment, Dong and colleagues asked some participants to describe an embarrassing situation from their past, while others in the control group were simply asked to describe a typical day at school; later, all participants rated various pairs of sunglasses.The findings showed that participants who relived their embarrassing experience tended to prefer large, darkly-tinted sunglasses. In effect, they favored the options that covered up their faces.In another experiment, embarrassed participants expressed greater interest in sunglasses and restorative face creams — products that would conceal or cover the faces — than in scarves or shoes.Additional research revealed that participants who actually used the “restorative” facial cream after re-experiencing an embarrassing moment reported lower embarrassment ratings, and they were more likely to seek out social interaction. Wearing sunglasses, however, did not seem to alleviate feelings of embarrassment.”Although embarrassment leads people both to hide their face and to restore their face, only by restoring their face can their embarrassment be decreased, as evidenced in their greater desire to participate in social activities,” Dong explains. “It is interesting to speculate that people who wear cosmetics on a daily basis may be more tolerant of potentially embarrassing behavior.”The findings highlight the unconscious influence that metaphorical thinking can have on everyday behaviors, but Dong notes that this influence may depend on cultural differences not examined in the present studies given that all participants were Hong Kong Chinese.”The metaphorical concept of ‘hiding one’s face’ is fairly widespread, but the concepts of ‘losing face’ and ‘saving face’ are more pervasive in Asian than in Western cultures,” she observes. “Although the effects of embarrassment on symbolically hiding one’s face are likely to generalize to Western cultures, the effect of symbolically restoring one’s face might not.”This research was supported by the Research Grants Council of Hong Kong.

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Often misidentified, multiracial people value accurate perceptions

Aug. 4, 2013 — Multiracial people may be misidentified more often as being white than black and may value being accurately identified more so than single-race individuals, according to research presented at APA’s 121st Annual Convention.”Today, the distinctions among white, black, Latino and Asian people are becoming blurred by the increasing frequency and prominence of multiracial people,” said Jacqueline M. Chen, PhD, of the University of California, Davis. “Still, average Americans have difficulty identifying multiracial people who don’t conform to the traditional single-race categories that society has used all their lives.”Chen discussed six experiments in which participants were consistently less likely to identify people as multiracial than single-race and took longer to identify someone as multiracial compared to how easily they identified black, white and Asian people. When they made incorrect identifications, they were consistently more likely to categorize a multiracial person as white than black, the study found. Time pressure, distractions and thinking of race in either-or terms made observers significantly less likely to identify someone as multiracial. The study was conducted at the University of California, Santa Barbara and involved 435 ethnically diverse undergraduate students.Participants identified the race of black, white, Asian or multiracial individuals in photos and researchers recorded each participant’s accuracy and time to respond. Researchers used a memorization task and a time limit in two experiments to determine if either would affect a participant’s accuracy. In another experiment, participants were told the study was about reading comprehension and attention. They then read news articles about scientists claiming to find a genetic basis for race and were asked to view several photographs of faces and identify them by race.Scientists agree that the racial categories we use today are not based on biological differences but are social constructions that can change over time, Chen said, noting that until the mid-20th century, the Anglo-Saxon majority in the United States viewed Irish and Italian immigrants as different races. …

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Moths talk about sex in many ways

July 8, 2013 — Moths are nocturnal, and they have one major enemy; the bat. As a defense many moths developed ears sensitive to the bat´s echolocation cries, and they have also developed different behaviors to avoid bats. Now it turns out that many moths are able to use both their hearing and their avoidance behavior to an entirely different purpose: to communicate about sex. According to a Danish/Japanese research team the various moth species probably talk about sex in a great number of different ways. This sheds new light on the evolution of sound communication and behavior.Moths have probably developed ears for the sole purpose of hearing if their worst enemy, the bat, is near. It has long been thought that moths were dumb, but many of them actually produce sounds — just so softly that bats cannot hear them. The moths use the sounds to communicate sexually. This scientists have known for a few years, and now new research reveals, that moths have developed different ways to not only use their sense of hearing, but also their avoidance behavior that was originally developed as a defense against bats.”We have examined two different moths and seen that they use their ears and behavior quite differently when they communicate sexually. There is no reason to believe that other moths do not do it in their own way, too. The variation in how to use these skills must be huge,” says sensory physiology researcher, Annemarie Surlykke from Department of Biological Sciences, University of Southern Denmark (SDU).She and her Japanese colleagues from University of Tokyo have studied the two species, Asian corn borer moth (Ostrinia furnacalis) and Japanese lichen moth (Eilema japonica). …

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Insulin differs between ethnicities, study finds

June 27, 2013 — People have differing abilities to release and react to insulin depending on ethnicity, according to a new study from researchers at Lund University in Sweden, Stanford University and Kitasato University.The results show that healthy subjects of all ethnicities were able to maintain a normal glucose level, but did so in different ways.”Africans tend to have lower insulin sensitivity. However, they appear to compensate for this by releasing larger quantities of insulin. Among those of East Asian origin, the reverse appears to be the case. They have very good insulin sensitivity, but appear to have a poorer ability to release more insulin if it is needed. Caucasians fall somewhere between the two extremes. Both insulin release and insulin sensitivity are affected,” says Damon Tojjar, a doctoral student at the Lund University Diabetes Centre (LUDC).When the researchers looked more closely at the research subjects who were at risk of developing diabetes and the subjects who had already been diagnosed, the same pattern was observed. Their results were generally worse, however, as their insulin production or insulin sensitivity had begun to fail as part of the disease.”The findings are consistent with what we see in clinical settings — East Asians are more sensitive to developing diabetes and they do so at a lower BMI. Because a lack of insulin is a condition for developing diabetes, it is not surprising that East Asians show lower insulin release and generally need to start insulin treatment at an earlier stage. The situation in Africa is still so complicated and heterogeneous that new studies are needed,” says Professor Leif Groop from LUDC.The researchers are not sure of the reasons for the physiological background to the changes, but suggest some possible explanations.”Our findings and the fantastic developments in genetic research make us optimistic that we can continue to map the important differences that cause a failure in the production of insulin and reduced insulin sensitivity, so that we can emphasise personalised treatment in the future,” concludes Damon Tojjar.About the studyIn type 2 diabetes, there are two main physiological functions that fail — the body’s ability to produce insulin and the body’s insulin sensitivity, i.e. the vast majority of cells’ ability to absorb glucose from the blood. …

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Fatty acids found in fish linked to lower risk of breast cancer

June 27, 2013 — A high intake of fatty acids found in fish is associated with a 14% reduction in the risk of breast cancer in later life, finds a study published on bmj.com today.The results show that each 0.1 g per day or 0.1% energy per day increment of intake of n-3 polyunsaturated fatty acid (n-3 PUFA) derived from fish was associated with a 5% reduction in risk. To achieve this risk reduction, intake of oily fish such as salmon, tuna or sardines should be 1-2 portions per person per week.Breast cancer is one of the most common cancers, accounting for 23% of total cancer cases and 14% of cancer deaths in 2008. Studies suggest that a healthy diet and lifestyle is crucial for the prevention of breast cancer, and dietary fat is one of the most intensively studied dietary factors closely related with risk.The n-3 PUFAs include ALA, EPA, DPA and DHA. They are involved in chemical messaging in the brain, helping to regulate blood vessel activity and areas of the immune system. The main dietary sources of EPA, DPA and DHA come from oily fish, while ALA is found mainly in nuts, seeds, and leafy green vegetables.Although n-3 PUFAs are the most promising types of fat to reduce cancer risk, results from human studies are inconsistent.So a team of researchers based in China set out to investigate the association between fish and n-3 PUFA intake and the risk of breast cancer. Levels were measured from both dietary sources and blood tests.They reviewed and analysed the results of 26 studies from the United States, Europe and Asia involving over 800,000 participants and over 20,000 cases of breast cancer.Marine n-3 PUFA was associated with a 14% reduction of breast cancer between the highest and lowest category of marine n-3 PUFA intake. The risk was lowest in Asian populations, probably because fish intake is much higher in Asia than in western countries, say the authors.Further analysis indicated a dose response: each 0.1 g per day or 0.1% energy per day increment of intake was associated with a 5% reduction in risk. However, no significant protective association was found for ALA — the plant based n-3 PUFA.The authors say their analysis, together with previous publications, “supports a protective role of marine n-3 PUFA on the incidence of breast cancer.”They conclude: “Our present study provides solid and robust evidence that marine n-3 PUFA are inversely associated with risk of breast cancer. The protective effect of fish or individual n-3 PUFA warrants further investigation of prospective studies.”

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Hot flashes before menopause? It can happen

June 12, 2013 — More than half of middle-aged women who still have regular cycles have hot flashes. Asian and Hispanic women are less likely to have them than white women, but compared with previous studies, the figures are surprisingly high, showed a survey of some 1,500 women published online today in Menopause, the journal of The North American Menopause Society (NAMS).The survey, conducted by researchers at Group Health (a large healthcare system in the Pacific Northwest) and Fred Hutchinson Cancer Research Center in Seattle, Washington, consisted of a diverse group of women, including whites, blacks, Hawaiian/Pacific Islanders, women of mixed ethnicity, Vietnamese, Filipinos, Japanese, East Indians, Chinese, and other Asians. The women were 45 to 56 years old, had regular cycles, had no skipped periods, and were not taking hormones.A surprising 55% of them reported having hot flashes or night sweats. (Previous studies pegged the highest rates at below 50%.) The groups with the highest proportions reporting hot flashes or night sweats were Native Americans (67%) and black (61%) women, but the differences between these groups and white women weren’t statistically significant. Fifty-eight percent of white women, the largest ethnic group, reported having hot flashes or night sweats.Compared with them, Asian and Hispanic women were significantly less likely to have these symptoms. Among Asian women, 31% of Filipino, 26% of Japanese, 25% of East Indian, 23% of “other Asian,” and 18% of Chinese women reported having hot flashes or night sweats. Twenty-six percent of Hispanic women reported these symptoms.Interestingly, white women who had symptoms were more likely to include soy in their diet, and white women who never had symptoms were more likely to have no soy in their diet.This study should help ease a worry for women who have been surprised by hot flashes and night sweats while they are still having regular cycles. It doesn’t necessarily mean they are in menopause yet, and it’s perfectly normal. “Some women even have a hot flash the first couple of nights after childbirth,” said Dr. Margery Gass, NAMS Executive Director.

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Taking back the yard: Dealing with invasive plants

June 12, 2013 — There’s nothing more frustrating for gardeners than discovering that their well-planned plots or rolling lawns have been infiltrated by invasive plant species, the perennial marauders of the back yard set. While many panic and immediately start yanking or mowing the intruders when they first make their appearance, gardening expert Karen Snetselaar, Ph.D., chair and professor of biology at Saint Joseph’s University, advises that it’s best to investigate the plant that’s choking your columbines or blighting your lawn before complicating the problem with an errant course of action.”Education is key,” Snetselaar says. “Find out what it is that you’re pulling from the ground. Knowing more about the invader will help you make better choices, and it’s less likely that you’ll be responsible for the proliferation of an invasive species.”According to Snetselaar, there are great online sources to consult, and each state’s department of natural resources will typically provide information about problem plants. In addition, the National Park Service’s Weeds Gone Wild site has a manageable list of factsheets for some of the most common invasives.Timing is critical for removing the more pernicious trespassers, says Snetselaar. Japanese stiltgrass (Microstegium vimineum) is a prime example. A weed that is spreading rapidly in the Mid-Atlantic States, this Asian native is dispersed by seed and grows prolifically in lawns. While it’s tempting to fire up the lawn mower when it’s detected, Snetselaar says that if it’s mowed, the stiltgrass will just produce seeds on tiny little plants. “It’s better to wait until the grass matures a little — not to the point where it’s actually making seeds, but just before that stage — and then pull it up by the roots.”On the other hand, Snetselaar notes, pulling up Japanese knotweed (Fallopia japonica), a notorious invader, isn’t recommended, because it can re-grow from even the tiniest bit of root. Herbicides and repeated cutting and bagging of the stems are the prescribed approaches.Invasive plants are likely to keep most of us busy for a long time, Snetselaar says, and factors that we can’t control, such as climate change and stormwater runoff will continue to result in new invasions. …

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Designated drivers don’t always abstain: One in three are impaired, study suggests

June 10, 2013 — Maybe better call that cab, after all: A new University of Florida study found that 35 percent of designated drivers had quaffed alcohol and most had blood-alcohol levels high enough to impair their driving.Adam Barry, an assistant professor of health education and behavior at UF, and his team interviewed and breath-tested more than 1,000 bar patrons in the downtown restaurant and bar district of a major university town in the Southeast. Of the designated drivers who had consumed alcohol, half recorded a blood-alcohol level higher than .05 percent — a recently recommended new threshold for drunken driving.”If you look at how people choose their designated drivers, oftentimes they’re chosen by who is least drunk or who has successfully driven intoxicated in the past — successful meaning got home in one piece … that’s disconcerting,” Barry said.The results are published in the July issue of the Journal of Studies on Alcohol and Drugs.The researchers recruited patrons as they left bars between 10 p.m. and 2:30 a.m. across six Friday nights before home football games in fall 2011. The mean age of the 1,071 people who agreed to be tested was 28. Most were white male college students, while 10 percent were Hispanic, 6 percent were Asian and 4 percent were African-American.After completing a 3-5 minute interview about demographic data and alcohol-related behaviors, participants then had their blood-alcohol content tested with a hand-held breath-testing instrument.The non-driving participants had significantly higher levels than the designated drivers, but 35 percent of the 165 self-identified designated drivers had been drinking. Seventeen percent of all those drivers tested had blood-alcohol levels between .02 and .049 percent, while 18 percent were at .05 percent or higher.The National Transportation Safety Board last month recommended all 50 states adopt a blood-alcohol content cutoff of 0.05 compared with the 0.08 standard used today to prosecute drunken driving. The American Medical Association made the same recommendation in the 1980s, Barry said.Barry said he doesn’t know why a designated driver would consume alcohol, but factors could include group dynamics or the driver’s belief that one or two drinks won’t impair his skills if he is an experienced drinker.Some field-based research suggests designated drivers might drink because the group did not consider who would drive before drinking commenced. Barry also suggested that it’s tricky for anyone to accurately evaluate their own sobriety.”That’s the insidious nature of alcohol — when you feel buzzed, you’re drunk,” he said.There is no universally accepted definition of a designated driver, according to the research. …

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Global highways of invasive marine species calculated

May 5, 2013 — Globalisation, with its ever increasing demand for cargo transport, has inadvertently opened the flood gates for a new, silent invasion. New research has mapped the most detailed forecast to date for importing potentially harmful invasive species with the ballast water of cargo ships.

Scientists from the Universities of Bristol, UK, and Oldenburg, Germany, have examined ship traffic data and biological records to assess the risk of future invasions. Their research is published in the latest issue of Ecology Letters.

Animals and plants can hitch a ride on cargo ships, hiding as stowaways in the ballast tanks or clinging to the ship’s hull. Upon arrival in a new port, alien species can then wreak havoc in formerly pristine waters. These so-called invasive species can drive native species to extinction, modify whole ecosystems and impact human economy.

Some regions, such as the San Francisco Bay or Chesapeake Bay, have even reported several new exotic species per year. The knock-on effects to fishermen, farmers, tourism and industry create billions of US dollars in damage every year. Conservationists and ship engineers are now trying to prevent the next big invasion. But without knowing when and where it may occur, their possibilities remain limited.

As part of the research project, funded by the Volkswagen Foundation, the team obtained detailed logs of nearly three million ship voyages in 2007 and 2008. Depending on the particular route travelled by each ship, the researchers estimated the probability that a species survives the journey and establishes a population in subsequent ports of call. Although this probability is tiny for any single voyage, the numbers quickly add up because modern cargo traffic volumes are enormous.

Professor Bernd Blasius from the University of Oldenburg and one of the researchers involved in the study, said: “Our model combines information such as shipping routes, ship sizes, temperatures and biogeography to come up with local forecasts of invasion probabilities.”

The final tally reveals the hotspots of bioinvasion. Large Asian ports such as Singapore and Hong Kong but also US ports like New York and Long Beach are among the sites of highest invasion probability. These waterways are notoriously busy, but, traffic is not the only important factor.

The North Sea, for example, does not rank among the top endangered regions despite intense shipping. Temperatures here are lower, making it more difficult for alien species to survive. However, arrivals from the other side of the Atlantic pose a serious threat to the North Sea. Most invaders are predicted to originate from the North American east coast.

Hanno Seebens from the University of Oldenburg said: “We also compared our model results to field data. And, indeed, most of the alien species actually do originate from there.”

As severe as the risk of future invasions may be, the study also contains a hopeful message. If ship engineers could prevent at least some potential invaders from getting on board, the total invasion risk could be substantially mitigated.

By successfully removing a species from 25 per cent of the ballast tanks arriving at each port (eg with filters, chemicals or radiation), the overall invasion probability decreases by 56 per cent. The reduction is so disproportionately large because the effect of ballast water treatment multiplies at successive stopovers.

Bioinvasion is, as the researchers admit, a complex process, and records of past invasions are far from comprehensive. Facing these uncertainties, they simulated various different scenarios. Interestingly, the key results are comparable for different models, predicting the same hotspots and global highways of bioinvasion. The traffic on the main shipping routes plays the greatest role for the calculation.

Dr Michael Gastner, Lecturer in Engineering Mathematics at the University of Bristol, added: “Ship movements in the past few years are well documented, but there are many unknowns about future trade routes.”

For example, the future of the world economy remains uncertain, and Arctic passages may become navigable as a consequence of global warming. Future simulations will also have to take into account which engineering solutions for ballast water treatment will eventually be adopted by port authorities.

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‘Boys will be boys’ in U.S., but not in Asia

May 22, 2013 — A new study shows there is a gender gap when it comes to behavior and self-control in American young children — one that does not appear to exist in children in Asia.

In the United States, girls had higher levels of self-regulation than boys. Self-regulation is defined as children’s ability to control their behavior and impulses, follow directions, and persist on a task. It has been linked to academic performance and college completion, in past studies by Oregon State University researchers.

In three Asian countries, the gender gap in the United States was not found when researchers directly assessed the self-regulation of 3-6 year olds. The results appear in the new issue of the journal Early Childhood Research Quarterly.

“These findings suggest that although we often expect girls to be more self-regulated than boys, this may not be the case for Asian children,” said Shannon Wanless, lead author of the study.

Wanless began conducting the research during her doctoral studies at Oregon State University under Megan McClelland, an associate professor in OSU’s Hallie E. Ford Center for Healthy Children and Families. Wanless is now on the faculty at the University of Pittsburgh.

One interesting part of the researcher’s findings: Although there were no gender differences in self-regulation when the children were directly assessed using a variety of school-readiness tasks, teachers in Asia perceived girls as performing better on self-regulation even when they actually performed equally to boys.

“Teachers are rating children’s behavior in the classroom environment, which has a lot of distractions and is very stimulating,” Wanless said. “It is possible that boys in the Asian countries were able to self-regulate as well as girls when they were in a quiet space (the direct assessment), but were not able to regulate themselves as well in a bustling classroom environment (teacher ratings).”

In addition, McClelland said cultural expectations of girls’ behavior versus that of their male peers may be influencing teachers’ assessments.

“In general, there is more tolerance for active play in boys than in girls,” McClelland said. “Girls are expected to be quiet and not make a fuss. This expectation may be coloring some teachers’ perceptions.”

The researchers conducted assessments with 814 children in the United States, Taiwan, South Korea and China. Their study showed that U.S. girls had significantly higher self-regulation than boys, but there were no significant gender differences in any Asian societies. In addition, for both genders, directly assessed and teacher-rated self-regulation were related to many aspects of school readiness in all societies for girls and boys.

“We know from previous research that many Asian children outperform American children in academic achievement,” McClelland said. “Increasingly, we are seeing that there is also a gap when it comes to their ability to control their behavior and persist with tasks.”

Wanless said this study paves the way for future research to explore why there is such a large gender gap in the United States, and what can be learned from Asian schools.

“What can we learn from Asian cultural and teaching practices about how we can support girls and boys to be successful in school?” she said. “When we see differences in developmental patterns across countries it suggests that we might want to look at teaching and parenting practices in those countries and think about how they might apply in the United States.”

Both researchers emphasized the importance of working with young children, regardless of gender or culture, on their self-regulation skills. Practicing games such as Simon Says and Red Light, Green Light are a few ways that parents can work with their children to help them learn how to follow instructions, persist on a task, and listen carefully.

“In our study, self-regulation was good for academic achievement for boys and girls,” Wanless said. “That means this skill is important for both genders and we should be supporting self-regulatory development for all children, especially boys. Low self-regulation in preschool has been linked to difficulties in adulthood, so increased focused on supporting young boys’ development can have long-term positive benefits.”

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