The researchers found that 22 percent of males and 5 percent of females ages 18-to-24 exhibit these disordered eating behaviors, which are defined as including at least one of the following: eating more or differently to gain weight or bulk up, and use of dietary supplements or anabolic steroids to achieve the same goal.

Left unchecked, these behaviors may escalate to muscle dysmorphia, characterized by rigid diet, obsessive over-exercising and extreme preoccupation with physique, say the researchers in their study publishing in the International Journal of Eating Disorders on June 20, 2019.

“Some eating disorders can be challenging to diagnose,” said first author Jason Nagata, MD, of the UCSF Division of Adolescent and Young Adult Medicine. “Unlike anorexia nervosa, which may be easily identified by parents or pediatricians, disordered eating to increase bulk may masquerade as healthy habits and because of this, it tends to go unnoticed.”

Heart Failure, Depression, Social Isolation in Worst Cases

At its most extreme, it can lead to heart failure due to insufficient calories and overexertion, as well as muscle dysmorphia, which is associated with social withdrawal and depression, Nagata said.

The 14,891 young adults in the study, who came from throughout the United States, had been followed for seven years. The researchers wanted to see if the early data, when the participants’ average age was 15, revealed something about their perceptions and habits that may serve as warning signs.

They found that boys who exercised specifically to gain weight had 142 percent higher odds of this type of disordered eating; among girls, the odds were increased by 248 percent. Boys who perceived themselves as being underweight had 56 percent higher odds; in girls the odds were 271 percent higher. Smoking and alcohol use in boys, and smoking in girls, increased odds moderately.

Additionally, being of black race bolstered odds by 66 percent in boys and 181 percent in girls.

Non-heterosexual identity, which the participants had been asked about when they reached adulthood, was not found to be a risk factor, the researchers said.

In young adulthood, 6.9 percent of males reported supplement use to gain weight or build muscle and 2.8 percent said they used anabolic steroids. Use by young women was significantly lower at 0.7 percent and 0.4 percent respectively.

“Supplements are a black box, since they are not regulated,” noted Nagata. “In extreme cases, supplements can cause liver and kidney damage. Anabolic steroids can cause both long-term and short-term health issues, including shrunken testicles, stunted growth and heart disease.”

Nagata said that clues that indicate behaviors may approach muscle dysmorphia include a highly restrictive diet that omits fats and carbohydrates, compulsive weighing and checking of appearance, and extensive time dedicated to exercise that may cut into social activities.

Co-authors: Senior author is Scott Griffiths, PhD, of Melbourne School of Physiological Sciences, University of Melbourne, in Australia. Co-authors are Stuart B. Murray, PhD, Kristen Bibbins-Domingo, PhD, MD, MAS, and Andrea Garber, PhD, RD, of UCSF; and Deborah Mitchison, PhD, of Macquarie University and Western Sydney University, in Australia.

Funding: Nagata is a participant in the Pediatric Scientist Development Program funded by the American Academy of Pediatrics and the American Pediatric Society; Murray was supported by the National Institutes of Mental Health; Garber was supported by the National Institutes of Health; and Griffiths is supported by a National Health and Medical Research Council Early Career Fellowship and a University of Melbourne Early Career Grant.

Ranavirus kills large numbers of European common frogs — the species most often seen in UK ponds — and is one of many threats facing amphibians worldwide.

Scientists from the University of Exeter and ZSL’s Institute of Zoology compared the bacteria living on frogs — known as their “microbiome” — from groups with varying history of ranavirus.

They found that populations with a history of outbreaks had a “distinct” skin microbiome when compared to those where no outbreaks had occurred.

“Whether a population of frogs becomes diseased might depend on the species of bacteria living on their skin,” said Dr Lewis Campbell.

“Ranavirus is widespread, but its presence in the environment doesn’t necessarily mean frogs become diseased — there appears to be some other factor that determines this.

“The skin is often the first infection point in ranavirus, and the first stage of the disease can be skin sores.

“It’s possible that the structure of a frog’s microbiome — the mix of bacteria on its skin — can inhibit the growth and spread of the virus so it can’t reach a level that causes disease.

“While the results of our study demonstrate a clear link between the frog skin microbiome and disease, further research will be need to understand the exact mechanisms which cause this relationship to form.”

Laboratory trials will help establish whether a history of ranavirus infection causes the microbiome differences, or whether these are pre-existing differences that predispose some populations to infection.

The scientists tested the skin bacteria of more than 200 wild adult European common frogs (Rana temporaria) from ten populations.

They found that the microbiome of individual frogs is usually most similar to that of others in the same population (those living in the same geographical area), but that populations with the same disease history were more similar to each other than to populations of the opposite disease history.

Even though amphibians can partially “curate” their microbiome by producing proteins that benefit specific bacteria, they are limited to those bacteria which are available in their environment.

Ranavirus can wipe out entire common frog populations and, though the new findings need further investigation, the researchers hope their work could help the species.

Dr Xavier Harrison said: “There’s growing evidence that skin bacteria may protect amphibians from lethal pathogens such as chytrid fungus, and that we can develop cocktails of probiotic bacteria to prevent vulnerable individuals from contracting disease.

“Our work suggests that given enough effort and research, similar probiotic therapies may be effective against ranavirus.”

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Researchers reported a major step forward Friday, publishing in Science Advances the discovery of a new explanation for asymmetrical thermoelectric performance, the phenomenon that occurs when a material that is highly efficient in a form which carries a positive charge is far less efficient in the form which carries a negative charge, or vice versa.

Zhifeng Ren, M. D. Anderson Chair Professor of Physics at the University of Houston, director of the Texas Center for Superconductivity at UH and corresponding author on the paper, said they have developed a model to explain the previously unaddressed disparity in performance between the two types of formulations. They then applied the model to predict promising new materials to generate power using waste heat from power plants and other sources.

The researchers already knew thermoelectric efficiency depends on the performance of the material in both forms, known as “p-type” and “n-type” for carrying a positive and negative charge, respectively. But most materials either don’t exist in both formulations or one type is more efficient than the other.

Promising New Material Synthesized

It is possible to build effective thermoelectric devices using just a p-type or n-type compound, but it is easier to design a device that contains both types; Ren said the best performance would come when both types exhibit similar properties.

The researchers synthesized one of the predicted materials, a zirconium-cobalt-bismuth compound, and reported a measured heat-to-electricity conversion efficiency of 10.6% at both the cold side, about 303 Kelvin, or about 86 degrees Fahrenheit, and the hot side, about 983 Kelvin (1,310 Fahrenheit) for both the p-type and the n-type.

Jun Mao, a post-doctoral researcher at UH and a first author of the report, said they determined the asymmetrical performance of some materials is linked to the fact that the charge moves at different rates in the two types of formulation. “If the charge movement of both the positive charge, for p-type, and the negative charge, for n-type, is similar, the thermoelectric performance of both types is similar,” he said.

Knowing that, they were able to use the mobility ratio to predict performance of previously unstudied formulations.

“When the thermoelectric performance for one type of a material has been experimentally studied, while the other type has not yet been investigated, it is possible to predict the ZT by using the identified relationship between the asymmetry and weighted mobility ratio,” the researchers wrote. ZT, or the figure of merit, is a metric used to determine how efficiently a thermoelectric material converts heat to electricity.

New Model Predicts Highly Efficient Materials

Hangtian Zhu, a post-doctoral researcher at UH and the report’s other first author, said the next step is determining how to formulate the corresponding type of material, once a material with a high efficiency in either p-type or n-type is found.

That can require experimentation to determine the best dopant — researchers tweak performance by adding a tiny amount of an additional element to the compound, known as “doping” — to improve performance, Zhu said.

That’s where the new understanding of asymmetrical performance comes in. Zhu said by predicting which compounds will have high performance in both types, researchers are encouraged to continue looking for the best combination, even if early efforts did not succeed.

Other researchers involved in the project are: Qing Zhu and Zihang Liu, both of UH; Yumei Wang of the Beijing National Laboratory for Condensed Matter Physics; and Zhenzhen Feng, Jifeng Sun and David J. Singh of the University of Missouri.

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Materials provided by University of Houston. Original written by Jeannie Kever. Note: Content may be edited for style and length.

“This data can provide us with insights into what genes are contributing to antibiotic resistance and whether they can be transferred to other bacteria that cause harm to humans and domesticated animals,” said Emmanuel Flores, a Masters student at CSU Fresno. “This work can be used as a form of monitoring antibiotic resistance and make accurate predictions in potential antibiotic resistance threats found in functional foods and livestock feed,” he said.

Bacillus is a group of bacteria that has been commonly used in probiotic products. These products are claimed to have some health benefit to the gut of those who consume these products. This research aimed to determine if any Bacillus bacteria used in probiotics are resistant to antibiotics that are commonly used in health clinics.

“Since bacteria have shown to be capable of transferring antibiotic resistance to other bacteria, we aim to determine if probiotic Bacillus are capable of transferring their own antibiotic resistance to bacteria that cause illnesses such as food poisoning,” said Flores.

Their results thus far have shown us that probiotic Bacillus has the potential to transfer antibiotic resistance. However, further tests need to be performed to determine what types of harmful bacteria are likely recipients of antibiotic resistance. The researchers plan to run a test that will facilitate the transfer of antibiotic resistance bookended by a test that will determine which antibiotics the harmful bacteria have gained resistance against.

Probiotics are available to the general public and come in the form of many functional foods and livestock feeds. “Monitoring the spread of antibiotic resistance by focusing on probiotics has been overlooked and should take place since the global impact of antibiotic resistance is increasing,” said Flores.

Laboratory work was performed by Emmanuel Flores who is a Masters student in Dr. Van Laar’s laboratory at CSU Fresno. He has worked under the guidance of Dr. Van Laar, Dr. Sistrom (UC Merced), and Mo Kaze (PhD student, UC Merced). Funding for this study was provided by the Bridge to Doctorate program and the CSU Fresno Graduate Net Initiative’s Graduate Research Grant awarded to Emmanuel. This work will be presented at ASM Microbe 2019 at the Moscone Center in San Francisco, California on Friday, June 21st, 2019.

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The researchers, led by Narayan Avadhani and Mrittika Chattopadhyay, suggest that the enzyme, mitochondrial CYP2D6, presents a potentially powerful new target for Parkinson’s treatment.

“Over the past two or three decades, researchers have tried inhibiting the process by which they believed MPTP was metabolized, with mixed success,” says Avadhani. “We believe that mitochondrial CYP2D6 is the more direct drug target, which might prove better in treating idiopathic Parkinson’s disease.”

The study, which appears in the Journal of Biological Chemistry, investigates the mechanism of Parkinson’s disease when a specific cause cannot be pinpointed, which is a majority of examples of the chemically induced disease.

Previous studies have shown that MPTP and similar toxic compounds induce Parkinson’s disease in rodents and primates. The mechanism of action, as scientists understood it, involved the compounds being oxidized to form MPP+, a toxic metabolite. The enzyme that was believed to be responsible is called monoamine oxidase B (MAO-B), present in the nervous system’s glial cells. In that conception of the mechanism, MPP+ was thought to then be transferred to dopamine neurons by dopamine transporter proteins, and, indeed, Parkinson’s is characterized by unusually low dopamine levels in the brain.

Researchers have tried to stem the effects of Parkinson’s by targeting two players in this presumed pathway, both MAO-B and the dopamine transporter protein, with only mixed success.

Yet the Penn-led study implicates an entirely separate mechanism. In earlier work, Avadhani and colleagues had shown that the enzyme CYP2D6, localized to the body’s energy factories, the mitochondria, could play a role in metabolizing MPTP to MPP+. In the new investigation, they took a closer look at beta-carbolines and isoquinolines, toxins that resemble MPTP which the body produces from substances found in tobacco smoke, alcohol, and some foods.

They found that, instead of MAO-B, it was mitochondrial CYP2D6 that activate the beta-carbolines and isoquinolines inside the dopamine-producing neurons, rather than the glial cells. This route of activation, in a mouse model, results in neuronal damage and oxidative stress, symptoms akin to Parkinson’s.

“CYP2D6 is known to play a role in influencing the activity of a number of drugs,” says Avadhani.

In an attempt to target this pathway, the researchers showed that mice lacking CYP2D6 did not exhibit the severe symptoms that mice with the protein did. In addition, an inhibitor of CYP2D6 prevented neuronal damage in the nice.

“The CYP2D6 inhibitor ajmalicine is a member of the reserpine family of alkaloids, found in the plant Rauwolfia serpentine and was long used in India for treating mental illness, such as paranoia and schizophrenia,” Avadhani says. “Mitochondrial targeting of such compounds is likely to be effective in treating Parkinson’s patients, and pursuing that is our future strategy.”