Culture

MINNEAPOLIS -The jury's still out on whether the use of marijuana may increase the risk of stroke. While several larger studies have found an increased risk, other studies have found no such increased risk. Adding to the debate is a new study that looked at recent marijuana use and risk of ischemic stroke published in the June 3, 2020, online issue of Neurology® Clinical Practice, an official journal of the American Academy of Neurology. Ischemic stroke is a stroke caused by a blockage in a blood vessel, such as a blood clot.

"Previous studies that investigated cannabis use and risk of stroke have had conflicting results, some showing a decreased risk and others showing a greatly increased risk," said study author Carmela V. San Luis, M.D., of the University of Mississippi in Jackson and a member of the American Academy of Neurology. "Our observational study looked specifically at recent cannabis use by reviewing drug testing data for people admitted to the hospital. While more research is needed with larger numbers of people, our study lends support to the studies showing that cannabis use does not increase the risk of stroke."

The study involved 9,350 people who were 18 years and older who had been admitted to a hospital and screened with a urine test for drug use. People who tested positive for drugs other than marijuana were excluded from the study. A total of 1,643 people, or 18%, tested positive for marijuana. Those who tested positive were more likely to be male, younger and current smokers than those who tested negative.

San Luis noted that the study captured only whether people had used marijuana recently. It did not collect information about how much marijuana was consumed or any other information about their history of prior use.

Of those who tested positive, 130 of 1,643 people, or 8%, had an ischemic stroke. Of those who tested negative, 16% had an ischemic stroke, or 1,207 of 7,707 people. But after researchers adjusted for other factors that affect stroke risk, such as age, high blood pressure, high cholesterol, sickle cell disease, obesity, diabetes, smoking and heart conditions, there was no link between recent cannabis use and either an increased or decreased risk of stroke.

The study was observational, so the results do not prove that recent marijuana use has no effect on a person's risk of stroke, they only show that researchers found an association.

"Our research adds to the list of studies with conflicting results, so it is important to continue to investigate stroke risk and cannabis use," said San Luis. "Future studies are now needed in larger groups of people that not only include data from drug screenings but also dosing amounts as well as a person's history of cannabis use."

Other limitations of the study include that information on synthetic cannabis was not available and researchers were unable to adjust for risk factors such as physical inactivity and body mass index.

The excellent results of the phase III international paediatric study, Inter-B-NHL ritux 2010, have been published today in the New England Journal of Medicine. This academic trial involved two international cooperative groups -- the European Intergroup for Childhood Non-Hodgkin Lymphoma (EICNHL) and the Children's Oncology Group (COG). The trial sponsors were Gustave Roussy (for countries in Europe and Asia) and COG (for Australia, Canadaand the United States) and included a partnership with Roche. It establishes a new standard treatment with an improved cure rate for children with advanced non-Hodgkin lymphoma, mainly Burkitt lymphoma. It supports the value of an immunotherapeutic agent, which was authorised in March 2020 by the European Commission for the treatment of a rare childhood cancer.

"With a three-year survival rate exceeding 95%, these results are outstanding. This study changes the international treatment bench-mark in young patients with advanced B-cell non-Hodgkin lymphoma", declared Dr. Véronique Minard-Colin, paediatrician at the Gustave Roussy Department of Child and Adolescent Oncology in France who coordinated this major international trial with Dr. Thomas G. Gross currently at Children's Hospital Colorado in the United States.

The management of children with Burkitt lymphoma has improved considerably over recent decades. Cure rates have risen from 30% in the 1980s to higher than 85% with chemotherapy alone (LMB protocol) with no major late sequelae associated with the medication or the disease. This conventional LMB treatment was established more than 30 years ago by Dr. Catherine Patte, paediatric oncologist at Gustave Roussy and her French collaborators. However, despite this advance, about 15% of children continued to die of this condition.

Rituximab is a monoclonal anti-CD20 antibody directed against lymphoma cells. This immunotherapeutic agent, developed by Roche is indicated in combination with chemotherapy as a treatment for adults with malignant non-Hodgkin lymphoma. The international Inter-B-NHL-ritux 2010 clinical trial evaluated rituximab in children and adolescents by means of a Paediatric Investigation Plan in the context of European Paediatric Regulation.

As Burkitt lymphoma is a rare disease (~1000/1200 new cases/year in Europe and in the US), 12 countries collaborated to address the question as to whether rituximab would increase survival of children and young adults. The Inter-B-NHL ritux 2010 phase III randomised trial was conducted between December 2011 and November 2015 and involved 328 patients age 2-18 years, treated in 176 centres distributed over four continents (Europe, North America, Australia and Asia). It assessed the effects of addition of rituximab to standard LMB chemotherapy in high-risk B-cell non-Hodgkin lymphoma (the majority with Burkitt lymphoma).

When rituximab is administered with chemotherapy, more than 95% of children and adolescents with advanced Burkitt lymphoma remain alive and disease-free after more than three years of follow-up. This new combined therapy increases overall survival by around 10% and reduces the rate of occurrence of an event (death, relapse, tumour progression, second cancer, etc.) by 70%.

Aggressive B-cell non-Hodgkin lymphoma is a cancer which develops in the lymphatic system, carrier of immune cells throughout the body. It can develop in any part of the body. It is most frequently seen in the abdomen and neck, areas which harbour many lymph nodes. It is one of the most aggressive cancers and grows very rapidly although it is rare and affects both children and adults. It is the most common lymphoma in children, accounting for more than 60% of paediatric non-Hodgkin lymphoma.

Cancers are fortunately rare in childhood, but this means that the development of new drugs to treat them must be conducted internationally. The Inter-B-NHL ritux 2010 trial is an excellent example of an international cooperation of academic clinical research in childhood cancer and of the importance of public-private collaborations with the pharmaceutical industry, so that positive findings result in marketing authorisation. The trial was run as part of a Paediatric Investigation Plan. Rituximab (MabThera®) has been authorised in Europe since March 2020 for the treatment of children with high-risk B-cell non-Hodgkin lymphoma. It will be available for all children and costs will be reimbursed through the health systems of member states and beyond.

This international trial was sponsored by Gustave Roussy and financed by a hospital clinical research programme of the French Ministry of Health (PHRC2010), Cancer Research UK, the National Institute for Health Research Clinical Research network, Children's Cancer Foundation Hong Kong, US National Cancer Institute, St. Baldrick's Foundation, and Roche.

Social media is an integral part of medicine, and an increasingly important conduit for sharing information about clinical trials. In an article in JCO Clinical Cancer Informatics, researchers from SWOG Cancer Research Network pose provocative questions aimed at sparking discussion and creating consensus on how cancer clinical trial stakeholders can best interact on social platforms.

Written by members of SWOG's digital engagement committee, the article notes the growing role that platforms like Facebook and Twitter play in raising awareness about trials and boosting their accrual. This significant promise - to make trials a larger part of the cancer care conversation and to make them more inclusive - is matched by significant legal, ethical, and logistical challenges for patients, researchers, institutional review boards, and trial sponsors.

According to the authors, these challenges include the risk of misinformation, the possibility of unblinding treatments used in trials, and the lack of clarity around regulatory oversight of social media content. What social content regarding cancer trials requires institutional review board approval before posting?

"With this article, we're raising the question: How can we best use social media to talk about cancer trials in ways that are meaningful, ethical, and engaging to every stakeholder?" said Krishna Gunturu, MD, a SWOG digital engagement team member, an oncologist with Lahey Hospital and Medical Center, and the lead author of the article. "To realize the potential of social media as a cancer trial educator and equalizer, we need consensus."

Specifically, the SWOG team asks:

Is it time to ask study volunteers to sign a code of conduct? This may help prevent disclosure of data during trial conduct and analysis, thus ensure the integrity of clinical trial data. A code, or confidentiality disclosure agreement, could also help patients by specifying that they maintain access to their own trial data.

Should social media be a required activity of a clinical researcher? The authors note that social media is an important way for researchers to directly engage with patients by sharing information, dispelling myths, and highlighting critical trials through direct digital conversation. To help, SWOG is creating social media toolkits to accompany new trials. The aim is to give study leaders access to IRB-approved information - text and graphics - that can be used in Twitter and Facebook posts as soon as their study opens.

Is there an appropriate scope of IRB review related to social media use? SWOG members point out that there are no rules for what kinds of social content requires IRB approval, and when and how. It's also not clear what constitutes "active" and "passive" social media recruitment under National Institutes of Health social media guidance.

How should sponsors collaborate with stakeholders on social media activities? Specifically, the SWOG team believes that patient advocates can play a critical role in public engagement in cancer trials. Advocates currently run a slew of Facebook and Twitter support groups for nearly every cancer type, and are often at the table when cancer trials are conceived and developed. Should trial sponsors do more to encourage patient advocate participation in social media?

"These are key questions, and we need to come together as a cancer clinical trial community to arrive at answers," said study co-author and SWOG Digital Engagement Committee Chair Don Dizon, MD, a professor of medicine at the Warren Alpert Medical School of Brown University and a member of the Lifespan Cancer Institute. "Our goal is to call everyone with a stake in cancer trials to action so we can use social media as a tool to advance cancer research."

A new study maps for the first time the evolutionary history of the world's terrestrial vertebrates: amphibians, birds, mammals and reptiles. It explores how areas with large concentrations of evolutionarily distinct species are being impacted by our ever-increasing "human footprint."

Research for the study was led by Dr. Rikki Gumbs of the EDGE of Existence Programme at the Zoological Society of London and Imperial College London and Dr. James Rosindell of Imperial College London in collaboration with Prof. Shai Meiri of the School of Zoology at Tel Aviv University's George S. Wise Faculty of Life Sciences and Steinhardt Museum of Natural History and other colleagues. The study was published in Nature Communications on May 26.

"Being 'evolutionarily distinct' means that you have no close living relatives," explains Prof. Meiri, who generated and interpreted the reptile-related data for the study. "In other words, you are alone on your branch of the evolutionary tree of life. Aardvarks, crocodiles, and kiwis were all separated from their closest evolutionary relatives tens of millions of years ago and bear a unique evolutionary history.

"The new research will provide a clear understanding of how best to protect nature given the current threats to specific locations and endangered species."

The researchers developed two new metrics that combine phylogenetic diversity and the extent of human pressure across the spatial distribution of species -- one metric valuing regions and another prioritizing species. They evaluated these metrics for reptiles, which have been largely neglected in previous studies, and contrasted these results with equivalent calculations for all terrestrial vertebrate groups. The researchers found that regions under high human pressure coincided with those containing irreplaceable reptilian diversity.

"Our analyses reveal the incomprehensible scale of the losses we face if we don't work harder to save global biodiversity," says Dr. Gumbs, the lead author on the paper. "To put some of the numbers into perspective, reptiles alone stand to lose at least 13 billion years of unique evolutionary history, roughly the same number of years as have passed since the beginning of the entire universe."

Using extinction-risk data for around 25,000 species, the researchers found at least 50 billion years of evolutionary heritage to be under threat, as well as a large number of potentially threatened species for which we lack adequate extinction risk data. This suggests that the calculation underestimates the number of species that may be affected.

According to the study's calculations, the Caribbean, the Western Ghats of India, and large parts of Southeast Asia -- regions that are home to the most unique evolutionary history -- are facing unprecedented levels of human-related devastation.

"This new study highlights which species should be prioritized for conservation, based on their evolutionary uniqueness and the intense human impact on environments where they are thought to dwell," Prof. Meiri says.

According to the research, the greatest losses of evolutionary history will be driven by the extinction of entire groups of closely-related species, such as pangolins and tapirs, and by the loss of highly evolutionarily distinct species, such as the ancient Chinese crocodile lizard (Shinisaurus crocodilurus); the Shoebill (Balaeniceps rex), a gigantic bird that stalks the wetlands of Africa; and the Aye-aye (Daubentonia madagascariensis), a nocturnal lemur with large yellow eyes and long spindly fingers.

The study highlights several unusual species as urgent conservation priorities, including the punk-haired Mary River turtle (Elusor macrurus), the Purple frog (Nasikabatrachus sahyadrensis), and the Numbat (Myrmecobius fasciatus). It also highlights many lesser known species, about which little is now understood by scientists, as priorities for further research. Adequate extinction risk data is currently lacking for more than half of the priority lizards and snakes identified.

"These are some of the most incredible and overlooked animals on Planet Earth," says Dr. Gumbs. "From legless lizards and tiny blind snakes to pink worm-like amphibians called caecilians, we know precious little about these fascinating creatures, many of which may be sliding silently toward extinction."

The study also identifies regions where concentrations of irreplaceable diversity are currently under little to no human pressure, particularly across the Amazon rainforest, the highlands of Borneo, and parts of southern Africa.

Co-author Dr. Rosindell concludes, "Our findings highlight the importance of acting urgently to conserve these extraordinary species and the remaining habitat that they occupy -- in the face of intense human pressures."

Toronto and Spanish physicians describe in CMAJ (Canadian Medical Association Journal) an approach to create dedicated COVID-19 patient units, infection control protocols and care teams to help other hospitals safely care for patients.

"The care of patients admitted to hospital with COVID-19 cannot be construed as falling within usual hospital operating procedures," writes Dr. David Frost, a general internist at University Health Network and the University of Toronto, Toronto, Ontario, with coauthors. "Meticulous planning is required. There are unique challenges regarding necessarily strict infection control procedures, provision of care to potentially large numbers of patients and clinical considerations specific to COVID-19."

The approach is based on real-world experience in Madrid, Spain, and from Toronto's University Health Network, one of Canada's largest hospitals, as well as relevant medical literature.

Some highlights include

Creating a dedicated COVID-19 unit with delineated risk zones and protocols

Establishing a buddy system for health care professionals to safely doff and don personal protective equipment (PPE)

Considering how rapidly care teams can be scaled up, how to integrate other physicians and how to maintain continuity of care

Standardizing procedures with checklists to maximize efficiency and safety for ward rounds

Adopting patient-centred practices to help lessen isolation and ensure links with families and caregivers

Fostering a culture of safety and clear communications to all stakeholders

To provide rapid access to the approach, the authors have created an open-access website http://www.torontocovidcollective.com.

"The ability to rapidly disseminate information, iterate protocols and collaborate with physicians around the world will continue to be important through subsequent waves of the pandemic," the authors write.

The Chapman University National COVID-19 and Mental Health Survey provides an in-depth look at the experiences of 4,149 adults living in the United States. The study asked questions about how the COVID-19 pandemic is impacting people's mental health, physical health, romantic relationships and encounters of prejudice and discrimination.

What Are the Effects of COVID-19 on Mental Health and Behaviors?

Conducted at the end of April 2020, survey findings revealed that most people are staying home more than normal (89%), and the majority reported feeling more stressed (61%), nervous, anxious, or on edge (60%), and feeling down, depressed, or hopeless (45%) than normal due to the effects of the COVID-19 pandemic. People attributed the changes in their health behaviors to the pandemic, with about one-third reporting eating more because of stress (37%), eating more junk food (41%) and getting less exercise (35%).

"As a nation, we have focused a lot of attention on the physical health risks of COVID-19 and not nearly as much on the mental health," said David Frederick, Ph.D., an associate professor of health psychology who led an all-Chapman team of researchers to conduct this study at the height of the pandemic. "We know from past research that natural disasters, epidemics and chronic stressors all harm our mental health, but what we're experiencing now is radically different than any of those previous experiences. The scale is so much larger."

The data also shows that essential workers like grocery store clerks, delivery personnel and restaurant employees are facing even worse mental and physical health problems. People in these occupations, where they are currently exposed to many people during the day, report more loneliness, anxiety, depression, negative emotions, negative health symptoms in the past week and more flu-like symptoms in the past month.

About half of respondents are "very concerned" about catching COVID-19 (54%), but about 42% believe their chances of catching the coronavirus are very low. Surprisingly, essential workers did not differ from other people in their concerns about catching COVID-19. Similar results were found for people who identified as being in a "frontline" job, such as healthcare professionals and police officers, where they did not perceive greater overall risks to COVID-19.

How is COVID-19 Affecting Romantic Relationships?

A snapshot of how people's romantic and sex lives were changing during the pandemic was analyzed from 2,702 survey participants who reported being in a long-term relationship. Sixty-four percent (64%) are spending more time with their partner, and the average couple snuggled four times and said "I love you" six times during the past week. Additionally, about one-fourth reported having fewer arguments with their partner in the past week (24%) while one-fourth reported having more arguments than normal (25%).

"Most people are spending more time with their romantic partner. For some couples, the silver lining is that they are getting to connect with their partner. For others, staying home together allows little stressors to build and blow up which then promotes conflict over existing disagreements," Frederick said.

A subset of people reported wanting to have sex more often with their partner (31%), versus only 22% who want sex less often than normal. Only 19% of the survey participants are having sex more often.

"Some couples are experiencing a disconnect sexually -- this is not surprising. One partner may want to have sex while the other partner is not interested at the moment," said co-investigator Amy Moors, Ph.D., assistant professor of psychology at Chapman and research fellow at The Kinsey Institute. "Anxiety and stress regarding health, finances, and a host of other thoughts that consume our cognitive energy can make it challenging to feel in the mood."

Among Ethnic Minorities, Do They Perceive Prejudice or Discrimination Related to Their Ethnicity and COVID-19?

The survey asked ethnic minorities to think about their experiences since the COVID-19 pandemic started and if they had experienced any incidents that they think were motivated specifically by connections between their ethnicity and COVID-19.

Thirty-two percent of Asian Americans and 38% of Chinese Americans reported at least one incident of racism. One-fourth of the Chinese Americans surveyed say they have experienced three or more racist incidents (25%). These include rude comments, feeling unwelcomed, being told to "go back" to their country, or being physically threatened.

Black Americans, who have been hardest hit as a group by COVID-19, were next most likely to report at least one incident (26%) and three or more incidents (21%).

Among both Blacks and Asians, experiencing more racist incidents was linked to greater stress, loneliness, anxiety, depression, negative emotions and number of health symptoms in the past week.

"I am troubled by these findings," said Jason Douglas, Ph.D., assistant professor of public health at Chapman and one of the researchers on the study. "We need clear and consistent messaging to indicate that viral pandemics do not stem from our ethnocultural minority communities. Rather, residents living in disadvantaged, ethnocultural minority communities are at greater risk for COVID-19 related morbidity and mortality due to longstanding systemic inequities that unfairly limit access to health-protective resources."

How Are People Coping with The COVID-19 Pandemic?

The most frequently used coping strategy was distraction through activities such as exercising, gardening, or watching television (69%). About half of people reported trying to find meaning in the experience by looking for something good in what was happening (48%). Thirty-six percent said that they have received comfort and understanding from someone, while 31% said that they found comfort in their religion or spiritual beliefs.

"How people cope in times of stress is very important," said Brooke Jenkins, Ph.D., assistant professor of health psychology at Chapman and one of the study's authors. "When stress is more outside of our control, techniques like distraction and reappraisal are beneficial. For example, if you feel that you have to stay home and that is outside of your control, then engaging in distracting activities like TV, gardening and exercise can be quite helpful."

For stress that seems more controllable, Dr. Jenkins recommends engaging in active coping. "For example, if you feel that you can actively reduce your risk of exposure to COVID-19, then getting advice from others and taking action to improve your situation will likely be helpful," she said.

The researchers saw that people who "took action to make their situation better" and who "looked for something good in what is happening" reported as having the best mental health. In contrast, people who gave up trying to deal with it, used drugs or alcohol, or said things to let unpleasant feelings escape tended to have worse mental health.

"The pandemic is creating many different stresses for people, there is no single strategy that will be optimal for coping with all of them," said Tara Gruenewald, Ph.D., associate professor of psychology at Chapman and project co-investigator. "A good rule of thumb is to gravitate toward those forms of healthy stress management you normally engage in, whether that is exercise, a good book, a favorite hobby, meditation or connecting with others. Of course, being safe and avoiding infection means we have to alter the way we engage in these activities, but the important thing is to make time to do them."

Methodology

The survey was conducted online through Amazon's Mechanical Turk. The survey asked participants to think about the effect that the COVID-19 pandemic has had on their lives within the past week. Only the 4,149 participants who passed standard data quality checks were analyzed. The study uses a national dataset from all 50 states, but the sample is not nationally representative. The sample included adults age 18 and older with the average age being 39. The survey was listed as the "Personal Attitudes and Experiences Study" to draw in a wide range of participants.

About 9,000 years ago in the Balsas River Valley of southwestern Mexico, hunter-gatherers began domesticating teosinte, a wild grass. Fast-forward to the present, and what was a humble perennial has been turned into the world's biggest grain crop: maize.

Humanity deeply relies on maize, or corn, but just when it became a major food crop in the Americas has been a source of mystery and dispute.

Now, a UC Santa Barbara researcher and his collaborators, by testing the skeletons of an "unparalleled" collection of human skeletal remains in Belize, have demonstrated that maize had become a staple in the Americas 4,700 years ago.

In a new paper, "Early isotopic evidence for maize as a staple grain in the Americas" in the journal Science Advances, Douglas J. Kennett, a UCSB anthropology professor, details how the discovery of human skeletons buried in a rock-shelter over a period of 10,000 years opened a window on maize consumption nearly three millennia before the rise of Maya civilization.

"What this paper shows is that by 4,700 years ago," Kennett said, "there is a significant shift towards maize cultivation and consumption, exceeding what we would consider to be a staple grain. And by 4,000 years ago maize was a persistently used staple and its importance continues through the Classic Maya period and until today."

Kennett, the paper's lead author, said the breakthrough came with the discovery of two rock-shelters with remarkably well-preserved skeletal remains in the Maya Mountains of Belize. Bones in the Neotropics typically degrade because of heat and humidity, but these rock shelters preserved the skeletal material well enough to measure stable isotopes revealing the diets of these people prior to death.

"The lowland Neotropics is not kind to organic material," Kennett said. "Bones degrade quickly if left out in the open. But these are special sites because they provide dry shelter from the elements that helps preserve bones that we were able to extract collagen from for nitrogen and carbon isotope analysis."

Maize synthesizes carbon using a distinctive photosynthetic pathway, which is evident isotopically in people that consume this important cultigen. There are very few plants in the lowland Neotropics that synthesize carbon in this way, so it's clear isotopically when people start eating substantial amounts of maize.

Skeletons dated to older than 4,700 years ago show minimal or no maize consumption. Some individuals dated to 4,700 to 4,000 years ago, however, show about 30% of maize consumption -- what Kennett calls a transitional period. By 4,000 years ago the carbon isotopic evidence indicates that maize consisted of more than 70% of the diet of individuals in the Maya lowlands.

"If you measured the isotopic composition of Maya people today," he said, "they would look very similar because they're consuming a great deal of maize on a daily basis. In terms of broader significance, this is the earliest evidence for the use of maize as a staple in the Americas that we're aware of so far."

The transition to agriculture in the Neotropics, as evidenced by the use of maize as a staple, has tantalizing implications for the rise of Maya civilization. As Kennett notes, where the Maya came from and when they moved into the area are still open questions. Classic Period Maya society didn't start to develop until about 2,000 years ago.

"So the question is, when do Maya people first move into the region and are they the earliest agriculturalists?" he said. "It is possible that the early agriculturalists identified in our study moved into the area and that they are somehow related to the Maya that we associate with emergence of Maya civilization later in time."

The Latin name for brook trout -- Salvelinus fontinalis -- means "speckled fish of the fountains," but a new study by Penn State researchers suggests, for the first time, that the larger streams and rivers those fountains, or headwaters, flow into may be just as important to the brook trout.

With few exceptions, brook trout are found now only in small mountain streams that stay cold enough year-round to meet their biological needs, below 68 degrees Fahrenheit. Because these trout in the United States are threatened by a warming climate, many have assumed those headwater habitats alone are critical for their survival.

But a genetic analysis of brook trout in streams across the 460-square-mile Loyalsock Creek drainage in north-central Pennsylvania shows that the fish are very similar genetically, suggesting close relatedness among populations. The only way that could have happened, according to researcher Shannon White, postdoctoral scholar in the College of Agricultural Sciences, is fish moving between tributaries in the 86-mile-long Loyalsock Creek.

Temperatures in Loyalsock Creek exceed brook trout thermal tolerance from approximately June through September, White pointed out, so fish are believed to inhabit only the bigger river system during the winter. Although the behavior and survival of brook trout in Loyalsock Creek are not well understood, researchers hypothesize that some brook trout move into the mainstem after spawning in a tributary in October or November and stay until late spring, when some swim up new tributaries.

"It's pretty simple -- if widespread populations are related genetically, it indicates that fish are moving around between those populations," she said. "There's a high degree of genetic connectivity between populations separated by the mainstem, and that indicates that brook trout are swimming into Loyalsock Creek and using it as a movement corridor to connect populations in other tributaries."

Understanding patterns of population connectivity is critical for species conservation, White added, because populations that are more connected typically are able to survive and adapt to disturbance and stress.

To build what White called "a family tree" of brook trout in the Loyalsock drainage, researchers collected 1,627 adult brook trout from 33 sites, with an average of 49 individuals collected from each site. They clipped the caudal fins of those fish and conducted genetic analysis on those tissue samples.

To estimate statistically how unique habitat features, such as road culverts and waterfalls found in streams, influence the movement of wild brook trout, researchers developed what they call the "bidirectional geneflow in riverscapes" model as part of a practical framework that uses genetic data to understand patterns and drivers of fish movement.

The novel modeling approach is significant, explained researcher Tyler Wagner, adjunct professor of fisheries ecology, because it shows that brook trout -- at least in the Loyalsock Creek watershed -- are not confined just to the headwaters. They are using the mainstem as a seasonal, thermally suitable corridor for movement.

There is no reason to expect that the Loyalsock drainage is different from others in the East, Wagner contends, so these results likely have implications for the conservation and management of wild brook trout. Specifically, these results suggest that conservation of larger streams and rivers may be necessary to protect and conserve critical brook-trout movement corridors that keep brook trout populations healthy.

"Some of the most fundamental questions in ecology relate to how organisms move through their environment," said Wagner, who is assistant leader of the U.S. Geological Survey's Pennsylvania Cooperative Fish and Wildlife Research Unit at Penn State. "These questions historically have been hard to address in fishes because it can be difficult statistically to estimate how unique habitat features found in streams and rivers influence movement. To address this void, we developed the riverscapes geneflow model."

The findings of the Penn State study, recently published in Ecological Applications, contrast with other research related to brook trout behavior, White conceded. The consensus has been that trout do not move very far, she said. "But Loyalsock Creek is a fairly big watershed, and we have found that fish are moving quite a bit, and populations on opposite ends of the watershed are connected to one another genetically."

However, White, who conducted a wide range of research on the brook trout population in the Loyalsock drainage while pursuing her doctoral degree in ecology at Penn State, noted that only a small proportion of the fish travel -- and it is not just the young males that branch out. This is different from most wildlife species.

"In a separate study we used telemetry to monitor the movement of 162 fish and found that there is a small proportion of the population that moves," she said. "It's only about 20% of fish that get into Loyalsock Creek. In terms of males, females, and the size of fish that are moving, it doesn't really seem to make a difference. This would suggest that there may be a genetic component to movement, in the sense that some fish have genes that are programmed to make them travel."

Below please find a summary and link(s) of new coronavirus-related content published today in Annals of Internal Medicine. The summary below is not intended to substitute for the full article as a source of information. A collection of coronavirus-related content is free to the public at http://go.annals.org/coronavirus.

1. Prevalence of Asymptomatic SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly throughout the world. Infected persons who remain asymptomatic may play a role in the ongoing pandemic, but their relative number and effect have been uncertain. Researchers from Scripps Research Translational Institute reviewed the available evidence on asymptomatic SARS-CoV-2 infection and found asymptomatic persons seem to account for approximately 40 to 45 percent of SARS-CoV-2 infections, and they can transmit the virus to others for an extended period, and conclude it is imperative that testing programs include those without symptoms. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-3012.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. The authors, Eric J. Topol, MD, and Daniel P. Oran, AM, can be reached by contacting Anna Andersen at aanders@scripps.edu.

2. Where Is the ID in COVID-19?

The coronavirus disease 2019 (COVID-19) pandemic has challenged all of medicine. However, in recent weeks, the nation's need for more infectious disease (ID) expertise has become a clear focal point. Cognitive specialties, such as ID, have attracted fewer physicians to the field than other, high-income-generating specialties. Authors from Massachusetts General Hospital and Lahey Hospital and Medical Center examined how the distribution of ID specialists matches the needs of the COVID-19 pandemic across the U.S. and found that nearly two-thirds of all Americans live in 90 percent of counties with below-average or no ID physician access. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-2684.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. The lead author, Rochelle P. Walensky, MD, MPH, can be reached at rwalensky@mgh.harvard.edu.

New results from the NASA/ESA Hubble Space Telescope suggest the formation of the first stars and galaxies in the early Universe took place sooner than previously thought. A European team of astronomers have found no evidence of the first generation of stars, known as Population III stars, as far back as when the Universe was just 500 million years old.

The exploration of the very first galaxies remains a significant challenge in modern astronomy. We do not know when or how the first stars and galaxies in the Universe formed. These questions can be addressed with the Hubble Space Telescope through deep imaging observations. Hubble allows astronomers to view the Universe back to within 500 million years of the Big Bang.

A team of European researchers, led by Rachana Bhatawdekar of the European Space Agency, set out to study the first generation of stars in the early Universe. Known as Population III stars [1], these stars were forged from the primordial material that emerged from the Big Bang. Population III stars must have been made solely out of hydrogen, helium and lithium, the only elements that existed before processes in the cores of these stars could create heavier elements, such as oxygen, nitrogen, carbon and iron.

Bhatawdekar and her team probed the early Universe from about 500 million to 1 billion years after the Big Bang by studying the cluster MACSJ0416 and its parallel field with the Hubble Space Telescope (with supporting data from NASA's Spitzer Space Telescope and the ground-based Very Large Telescope of the European Southern Observatory). "We found no evidence of these first-generation Population III stars in this cosmic time interval" said Bhatawdekar of the new results.

The result was achieved using the Hubble's Space Telescope's Wide Field Camera 3 and Advanced Camera for Surveys [2], as part of the Hubble Frontier Fields programme. This programme (which observed six distant galaxy clusters from 2012 to 2017) produced the deepest observations ever made of galaxy clusters and the galaxies located behind them which were magnified by the gravitational lensing effect, thereby revealing galaxies 10 to 100 times fainter than any previously observed. The masses of foreground galaxy clusters are large enough to bend and magnify the light from the more distant objects behind them. This allows Hubble to use these cosmic magnifying glasses to study objects that are beyond its nominal operational capabilities.

Bhatawdekar and her team developed a new technique that removes the light from the bright foreground galaxies that constitute these gravitational lenses. This allowed them to discover galaxies with lower masses than ever previously observed with Hubble, at a distance corresponding to when the Universe was less than a billion years old. At this point in cosmic time, the lack of evidence for exotic stellar populations and the identification of many low-mass galaxies supports the suggestion that these galaxies are the most likely candidates for the reionisation of the Universe. This period of reionisation in the early Universe is when the neutral intergalactic medium was ionised by the first stars and galaxies.

"These results have profound astrophysical consequences as they show that galaxies must have formed much earlier than we thought," said Bhatawdekar. "This also strongly supports the idea that low-mass/faint galaxies in the early Universe are responsible for reionisation."

These results [3] also suggest that the earliest formation of stars and galaxies occurred much earlier than can be probed with the Hubble Space Telescope. This leaves an exciting area of further research for the upcoming NASA/ESA/CSA James Webb Space Telescope -- to study the Universe's earliest galaxies.

BUFFALO, N.Y. - Lockdowns implemented across the world due to the COVID-19 pandemic have negatively impacted diet, sleep and physical activity among children with obesity, according to University at Buffalo research.

The study, published in April in Obesity, examined 41 overweight children under confinement throughout March and April in Verona, Italy.

Compared to behaviors recorded a year prior, the children ate an additional meal per day; slept an extra half hour per day; added nearly five hours per day in front of phone, computer and television screens; and dramatically increased their consumption of red meat, sugary drinks and junk foods.

Physical activity, on the other hand, decreased by more than two hours per week, and the amount of vegetables consumed remained unchanged.

"The tragic COVID-19 pandemic has collateral effects extending beyond direct viral infection," says Myles Faith, PhD, UB childhood obesity expert and co-author on the study. "Children and teens struggling with obesity are placed in an unfortunate position of isolation that appears to create an unfavorable environment for maintaining healthy lifestyle behaviors."

"Recognizing these adverse collateral effects of the COVID-19 pandemic lockdown is critical in avoiding the depreciation of hard-fought weight control efforts among youths afflicted with excess weight," says Faith, chair and professor of counseling, school and educational psychology in the UB Graduate School of Education.

The study was led by Steven Heymsfield, MD, professor at the Louisiana State University Pennington Biomedical Research Center; and Angelo Pietrobelli, MD, professor at the University of Verona in Italy.

Children and adolescents typically gain more weight during summer vacation than during the school year, says Faith, which led the researchers to wonder if being homebound would have a similar effect on the kids' lifestyle behaviors.

"School environments provide structure and routine around mealtimes, physical activity and sleep - three predominant lifestyle factors implicated in obesity risk," says Faith.

The researchers surveyed 41 children and teens with obesity in Verona, Italy, who were involved in an ongoing long-term study. Lifestyle information regarding diet, activity and sleep was collected three weeks into Italy's mandatory national lockdown and compared to data on the children gathered in 2019. Questions focused on physical activity, screen time, sleep, eating habits, and the consumption of red meat, pasta, snacks, fruits and vegetables.

The results confirmed the negative change in behavior, indicating that children with obesity fare worse on weight control lifestyle programs while at home compared to when they are engaged in their school curriculum.

"Depending on the duration of the lockdown, the excess weight gained may not be easily reversible and might contribute to obesity during adulthood if healthier behaviors are not re-established," says Faith. "This is because childhood and adolescent obesity tend to track over time and predict weight status as adults."

Government officials and policymakers should consider the potential harmful effects of lockdowns on youths with obesity when making decisions regarding when and how to loosen restrictions, says Faith.

There is also a need to establish and evaluate telemedicine programs that encourage families to maintain healthy lifestyle choices during periods of lockdown, he adds.

Faith and colleagues are conducting an ongoing National Institutes of Health-funded study that is testing a family-based treatment for childhood obesity using telemedicine technology that allows participants to be treated in their homes.

A new, hair-sprouting dollop of human skin created in the lab might one day help prevent hair loss.

Organoids are small, lab-grown cell groupings are designed to model real-world organs -in this case, skin. A paper published in Nature describes the hairy creation as the first hair-baring human skin organoid made with pluripotent stem cells, or the master cells present during early stages of embryonic development that later turn into specific cell types.

The hirsute organoid's development was led by Karl Koehler, Ph.D., formerly of Indiana University School of Medicine and now at Boston Children's Hospital. An Oregon Health & Science University graduate student, Benjamin Woodruff, contributed by helping make the organoids as a post-baccalaureate research technician in the Stanford University lab of Stefan Heller, Ph.D.

"This makes it possible to produce human hair for science without having to take it from a human," explained Woodruff, who now is completing his first year of cell and developmental biology graduate studies at OHSU. "For the first time, we could have, more or less, an unlimited source of human hair follicles for research."

Having access to more hair-growing skin can help researchers better understand hair growth and development - and maybe even provide clues needed to reverse a retreating hair line.

The coronavirus has prompted many medical centers to switch from in-person appointments to video visits. A new study from UCSF Benioff Children's Hospitals suggests that for some hospitals, video visits may become a permanent feature of the patient-provider landscape.

Prior to March 2020, all patients at the UCSF Adolescent and Young Adult Clinic received medical care through in-person visits. By the end of March, 97 percent of visits -- approximately 80 appointments per week -- were done via videoconferencing with physicians or nurse practitioners, according to the study publishing June 3, 2020, in the Journal of Adolescent Health.

"This has been a complex transition because we have had to navigate the uncertain waters of parent and adolescent/young adult involvement and confidentiality," said senior author Marissa Raymond-Flesch, MD, of the UCSF Division of Adolescent and Young Adult Medicine. "However, after the current coronavirus crisis, we expect to maintain telehealth in many areas.

"Patients will be able to complete video visits from school or work, or any setting that they identify as adequately private," Raymond-Flesch said. "This is a new domain in our field, and we are excited about reducing disparities in care in underserved areas such as rural communities."

The clinic serves patients ages 12 to 25, of whom three-quarters are female, from a catchment area spanning 400 miles north to the Oregon border and roughly 100 miles east to the Central Valley. Service includes both general health care and specialty care in attention and mood disorders, sexual and reproductive health, eating disorders and addictions.

Virtual Waiting Rooms Protect Patient Privacy

In their study, the UCSF researchers used a videoconferencing platform that was compliant with the Health Insurance Portability and Accountability Act, which protects the privacy of health information and security of electronic records. To prevent third-party access, they created a virtual waiting room, requiring a doctor to authorize entrance for each visitor. The visits were streamed -- like FaceTime or Google Hangouts -- rather than recorded. They also identified ways for patients to share information without risking disclosure to people within earshot, such as by using headphones and responding to sensitive questions with "yes" or "no," as well as using the chat function to type responses.

"The telehealth visit is a new reality and one that presents unique challenges," said Raymond-Flesch. "While you can see the patient's face, you cannot make direct eye-contact and you cannot demonstrate compassion by offering a tissue or a gentle pat on the arm. I found it meant that I had to exaggerate facial expressions or offer more verbal assurance than I would have done in actual visits."

The researchers reported that virtual visits did not present a barrier in screening patients for depression, substance use or psycho-social development. Additionally, clinicians were able to provide contraceptive counselling and appropriate follow-up for established diagnoses like headache, acne and back pain; and they reported that they were comfortable managing mood disorders and medication maintenance for attention deficit hyperactivity, with referrals made to psychiatrists for some conditions.

More challenging were appointments that required exams and procedures. Patients needing vaccines or tests for pregnancy, sexually transmitted diseases, urinary-tract infections or high cholesterol required an in-person visit with a nurse or phlebotomist. While the researchers have not considered using devices such as electronic stethoscopes, which enable providers from a second clinic to stream data directly to the consulting site, they said patient-owned devices such as an Apple watch or blood pressure monitor and upper-arm cuff may be used in the future, pending tests for accuracy.

Weight Checks a Challenge for Patients with Eating Disorders

Virtual care for patients with eating disorders, who make up about a third of the clinic's patients, required significant workarounds to provide regular monitoring of weight, vital signs and electrolytes. Weight checks, in particular, can be very stressful for these patients and many prefer to not know their weight. In some cases, primary care providers or therapists were able to weigh patients and take vital signs, which they shared with the clinic. In other cases, a parent or trusted adult was tasked with weighing the patient and relaying that information in private to the clinician.

"There were concerns that patients would overhear their weight or learn of nutritional interventions that normally parents would discuss confidentially with the physician during an in-person appointment," said Raymond-Flesch. "But on the upside, many families travel significant distances to reach us. Telemedicine may have allowed for increased parental participation," she said noting that patients with eating disorders were referred from a much broader geographic range than primary-care patients.

In addition to improved accessibility, telemedicine also opened the door to collaboration with primary-care providers. "It's something that has been considered before but never implemented," said first author and clinical fellow Angela Barney, MD, of the UCSF Division of Adolescent and Young Adult Medicine.

"There's a sense that many of the changes are not just temporary responses, but rather the new normal," she said. "We are not proposing that telemedicine for adolescents and young adults will replace in-person visits, but we can look at this quick shift as an opportunity to reach our patient population in new ways, both in this time of crisis and beyond."

People with severe vision loss can less accurately judge the distance of nearby sounds, potentially putting them more at risk of injury, according to new research published in the journal Scientific Reports.

Researchers from Anglia Ruskin University's Vision and Eye Research Institute (VERI) tested participants with different levels of vision loss, presenting them with speech, music and noise stimuli, and different levels of reverberation (echoes).

Participants were asked to judge the distance of the different sounds, as well as the size of the room.

People with severe visual loss judged closer sounds more inaccurately compared to those whose vision loss is less severe, who in turn, were less accurate when compared to people with normal sight.

For more distant sounds, people with severe visual loss judged these to be twice as far away when compared to normal sighted individuals. Participants with severe sight loss also judged the rooms to be three times larger than the control group of normal sighted individuals.

Professor Shahina Pardhan, Director of VERI, said: "Vision loss means people rely more on their hearing for awareness and safety, communication and interaction, but it was not known how hearing is affected by the severity of partial vision loss.

"The results demonstrate that full blindness is not necessary for judged auditory distance and room size to be affected by visual loss, and that changes in auditory perception are systematic and related to the severity of visual loss.

"Our research found that more severely visually impaired people were less accurate in judging the distance of closer sounds, which may make it harder for them in real-life situations, for example such as crossing busy streets."

Almost any grocery store is filled with products made from corn, also known as maize, in every aisle: fresh corn, canned corn, corn cereal, taco shells, tortilla chips, popcorn, corn sweeteners in hundreds of products, corn fillers in pet food, in soaps and cosmetics, and the list goes on.

Maize is perhaps the most important plant ever domesticated by people, topping 1 billion tonnes produced in 2019, double that of rice, according to University of New Mexico Anthropology professor Keith Prufer, Principle Investigator of a team that just released new research that sheds light on when people started eating maize.

Recently published research from his team in the journal Science Advances reveals new information about when the now-ubiquitous maize became a key part of people's diets. Until now, little was known about when humans living in the tropics of Central America first started eating corn. But the "unparalleled" discovery of remarkably well-preserved ancient human skeletons in Central American rock shelters has revealed when corn became a key part of people's diet in the Americas.

"Today, much of the popularity of maize has to do with its high carbohydrate and protein value in animal feed and sugar content which makes it the preferred ingredient of many processed foods including sugary drinks. Traditionally it has also been used as fermented drink in Mesoamerica. Given its humble beginnings 9,000 years ago in Mexico, understanding how it came to be the most dominant plant in the world benefits from deciphering what attracted people to this crop to begin with. Our paper is the first direct measure of the adoption of maize as a dietary staple in humans," Prufer observed.

Prufer said the international team of researchers led by UNM and University of California, Santa Barbara is investigating the earliest humans in Central America and how they adapted over time to new and changing environments, and how those changes have affected human life histories and societies.

"One of the key issues for understanding these changes from an evolutionary perspective is to know what the change from hunting and gathers pathways to the development of agriculture looked like, and the pace and tempo of innovative new subsistence strategies. Food production and agriculture were among most important cultural innovations in human history.

"Farming allowed us to live in larger groups, in the same location, and to develop permanent villages around food production. These changes ultimately led in the Maya area to the development of the Classic Period city states of the Maya between 3,000 and 1,000 years ago. However, until this study, we did not know when early Mesoamericans first became farmers, or how quickly they accepted the new cultigen maize as a stable of their diet. Certainly, they were very successful in their previous foraging, hunting, and horticultural pursuits before farming, so it is of considerable interest to understand the timing and underlying processes," he said.

Radiocarbon dating of the skeletal samples shows the transition from pre-maize hunter-gatherer diets, where people consumed wild plants and animals, to the introduction and increasing reliance on the corn. Maize made up less than 30 percent of people's diets in the area by 4,700 years ago, rising to 70 percent 700 years later.

Maize was domesticated from teosinte, a wild grass growing in the lower reaches of the Balsas River Valley of Central Mexico, around 9,000 years ago. There is evidence maize was first cultivated in the Maya lowlands around 6,500 years ago, at about the same time that it appears along the Pacific coast of Mexico. But there is no evidence that maize was a staple grain at that time.

The first use of corn may have been for an early form of liquor.

"We hypothesize that maize stalk juice just may have been the original use of early domesticated maize plants, at a time when the cobs and seeds were essentially too small to be of much dietary significance. Humans are really good at fermenting sugary liquids into alcoholic drinks. This changed as human selection of corn plants with larger and larger seeds coincided with genetic changes in the plants themselves, leading eventually to larger cobs, with more and larger seeds in more seed rows," Prufer explained.

To determine the presence of maize in the diet of the ancient individuals, Prufer and his colleagues measured the carbon isotopes in the bones and teeth of 52 skeletons. The study involved the remains of male and female adults and children providing a wholistic sample of the population. The oldest remains date from between 9,600 and 8,600 years ago and continues to about 1,000 years ago

The analysis shows the oldest remains were people who ate wild plants, palms, fruits and nuts found in tropical forests and savannahs, along with meat from hunting terrestrial animals.

By 4,700 years ago, diets had become more diverse, with some individuals showing the first consumption of maize. The isotopic signature of two young nursing infants shows that their mothers were consuming substantial amounts of maize. The results show an increasing consumption of maize over the next millennium as the population transitioned to sedentary farming.

Prufer noted, "We can directly observe in isotopes of bone how maize became a staple grain in the early populations we are studying. We know that people had been experimenting with the wild ancestor of maize, teosintle, and with the earliest early maize for thousands of years, but it does not appear to have been a staple grain until about 4000 BP. After that, people never stopped eating corn, leading it to become perhaps the most important food crop in the Americas, and then in the world."

Excavations were directed by Prufer along with an international team of archaeologists, biologists, ecologists and geologists. Numerous UNM graduate and undergraduate students took part in the field research as well as collaborators with the protected area co-management team, a Belizean NGO the Ya'axche' Conservation Trust.

Conditions weren't easy for the excavation teams, Prufer noted: "We did five years of fieldwork in two very remote rock shelter sites in the Bladen Nature Reserve in the Maya Mountains of Belize, a vast wilderness area that is a two-day walk from the nearest road. To work in this area we had to camp with no electricity, running water, or even cell service for a month at a time each year."

Analysis was conducted at Penn State University, UNM Center for Stable Isotopes, UCSB, and Exeter University in the UK. Prufer was the project director along with his colleague Doug Kennett from UCSB. The project was funded by the Alphawood Foundation and the National Science Foundation. The study was conducted by researchers from UNM, UCSB, Pennsylvania State University, University of Exeter, The US Army Central Identification Laboratory, University of Mississippi, Northern Arizona University, and the Ya'axche Conservation Trust in Belize.

Now that the research is published, the team will advance it to the next stage.

"New technologies allow us to look even deeper into molecular analysis through studies of ancient DNA and isotopic analysis of individual amino acids that are involved in turning food into building blocks of tissues and energy. We already have a Ph.D. students working on expanding our work to the next generation of analysis," Prufer said.