Culture

Wine lovers recognize that a perfectly paired wine can make a delicious meal taste even better, but the reverse is also true: Certain foods can influence the flavors of wines. Now, researchers reporting in ACS' Journal of Agricultural and Food Chemistry have explored how lipids -- fatty molecules abundant in cheese, meats, vegetable oils and other foods -- interact with grape tannins, masking the undesirable flavors of the wine compounds.

Tannins are polyphenolic compounds responsible for the bitterness and astringency of red wines. Wine testers have noticed that certain foods reduce these sensations, improving the flavor of a wine, but scientists aren't sure why. Some studies have indicated that tannins interact with lipids at the molecular level. In foods, lipids are found as fat globules dispersed in liquids or solids. Julie Géan and colleagues wanted to investigate how tannins influence the size and stability of lipid droplets in an emulsion. They also wondered how the prior consumption of vegetable oils would impact the taste of tannins for human volunteers.

The researchers made an oil-in-water emulsion using olive oil, water and a phospholipid emulsifier. Then, they added a grape tannin, called catechin, and studied the lipids in the emulsion with various biophysical techniques. The team found that the tannin inserted into the layer of emulsifier that surrounded the oil droplets, causing larger droplets to form. In taste tests, volunteers indicated that consuming a spoonful of rapeseed, grapeseed or olive oil before tasting a tannin solution reduced the astringency of the compounds. Olive oil had the greatest effect, causing the tannins to be perceived as fruity instead of astringent. Combining the biophysical and sensory results, the researchers concluded that tannins can interact with oil droplets in the mouth, making them less available to bind to saliva proteins and cause astringency.

DALLAS, March 3, 2021 -- American Indian people with atrial fibrillation (AFib) had the highest risk of non-hemorrhagic stroke when compared with people in other racial and ethnic groups, and they also experienced the highest overall risk for stroke even without atrial fibrillation (AFib), according to new research published today in the Journal of the American Heart Association, an open access journal of the American Heart Association.

"In previous research, we have confirmed that American Indian individuals, when compared with those in other racial or ethnic groups, have the highest risk of atrial fibrillation, which is a quivering or irregular heartbeat that can substantially increase the risk of blood clots and stroke," said lead study author Gregory M. Marcus, M.D., M.A.S., a cardiologist, professor of medicine and associate chief of cardiology for research at the University of California, San Francisco. "While American Indian people are known to have a particularly high risk for stroke in general, the relationship between AFib and non-hemorrhagic, or non-bleeding, stroke among this group has not been thoroughly studied."

In this study, researchers reviewed medical records for nearly 17 million adults (ages 18 or older) who were treated in hospitals or ambulatory care settings throughout the state of California between January 1, 2005 and December 31, 2011 and followed for a median of 4.1 years. About 0.6% of the patients were of American Indian descent; 56.7% were non-Hispanic white people; 25.9% were Hispanic people; 8.7% were of Asian descent; and 8.1% were Black people. During the four years of follow-up, there were 166,826 non-hemorrhagic strokes, of which, 36,950 strokes occurred among patients with atrial fibrillation.

As a group, American Indian people experienced the highest rates of non-hemorrhagic stroke whether compared to people in all the other racial and ethnic groups in the study combined, or when compared individually to each racial and ethnic group. Among the specific findings:

American Indian people had a 47% higher risk of non-hemorrhagic stroke when compared with all the people in all of the other racial and ethnic groups;

American Indian people with AFib had a 38% higher risk of stroke when compared with people in the other population groups who also had AFib;

Atrial fibrillation alone could not explain the elevated risk: American Indian adults without AFib had a 59% higher risk of stroke compared with adults in the other racial and ethnic groups without AFib; and

Overall, American Indian adults had higher rates of Type 2 diabetes, obesity and smoking, which are known risk factors for stroke. American Indian people also had lower rates of health insurance coverage and lower income levels.

"The results of our study add to the growing body of evidence that race and ethnicity are important factors when assessing stroke risk," Marcus said. "However, our findings that conventional risk factors such as AFib may not be the cause for this increased risk among American Indian individuals, suggest other influences are in play. These could possibly be related to hereditary factors, environmental exposures or disparities in access to healthcare, and this clearly warrants further attention."

The study's findings are observational, and while a large group of adults were analyzed, only people receiving treatment in California were included in the analysis. Marcus said the next step is to expand on these findings, such as conducting randomized trials among American Indian populations, to determine the most effective ways to save lives.

"American Indian people experience the highest rates of stroke in our society. Together, regular preventive care that includes routine screening and treatment for hypertension and Type 2 diabetes, along with regular follow-up that may detect other conditions such as atrial fibrillation, accompanied by guideline-directed care could help mitigate this heightened risk for stroke, which is largely preventable," Marcus said. "And, then there remains the challenge of determining optimal methods to actually implement these strategies in the real world that can improve people's health and lives."

This study's focus and findings reinforce the American Heart Association's November 2020 Presidential Advisory, "Call to Action: Structural Racism as a Fundamental Driver of Health Disparities." The advisory declared structural racism as a major cause for poor health and premature death from heart disease and stroke for many and detailed the Association's immediate and ongoing action to accelerate social equity and health care and outcomes for all people.

In a report summary released today Thomas McAndrew, a computational scientist and assistant professor at Lehigh University's College of Health includes probabilistic forecasts of the impact of vaccines and variants on the U.S. COVID trajectory over the next few weeks. The goal of the report, says McAndrew, is "to support public health officials, infectious disease modeling groups, and the general public"

Report highlights:

A consensus of 91 forecasters predicts that the B.1.1.7. variant will be found in 42% of all genetic sequences with an S-gene mutation in the first two weeks of March and in 72% in all sequences between March 29 and April 4, 2021.

The consensus among experts in the modeling of infectious disease and trained forecasters from Metaculus is that by Feb 28th, 55,420,000 people will have received at least one dose of a vaccine. Generalist forecasters from Good Judgment Open (GJO) - an online forecasting platform open to any interested member of the public - responded similarly with an implied median of 52,200,000 people receiving one or more vaccine doses. Preliminary data from the CDC shows 49,772,180 people have received an initial dose on Feb. 28th.

Consensus forecasts from both Metaculus and Good Judgment Open predicted a decrease in the rate of cases, deaths, and hospitalizations for the last week of Feb (21st-27th).

The team will share with members of the Centers for Disease Control and Prevention (CDC), the Council of State and Territorial Epidemiologists, and members of MIDAS.

McAndrew's approach to forecasting is different from the traditional approach. Rather than build a computational model to predict cases, deaths, and hospitalizations due to COVID, he asks experts and trained forecasters to predict these targets and combines their predictions into a single consensus forecast.

In addition he and his team produce a metaforecast, which is a combination of an ensemble of computational models and their consensus forecast.

"The idea behind this approach is to combine computational models with human judgment to make more accurate predictions of the U.S. outbreak," says McAndrew.

Researchers have captured the first detailed images of newborn babies' lungs as they take their first breaths.

The research, led by the Murdoch Children's Research Institute (MCRI) and published the American Journal of Respiratory and Critical Care Medicine, provides a breakthrough in understanding the events around a baby's first breath, why healthy babies cry at birth and provides clues to improving preterm babies' survival chances and long term health outcomes.

About 10 per cent of newborns, and almost all preterm infants, need resuscitation because their lungs do not properly fill with air at birth (a process called lung aeration). Despite this, MCRI Associate Professor David Tingay said that birth was one of the most poorly understood respiratory events in medicine due to the difficulties of imaging a newborn's lungs.

The research involved studying full-term infants born at The Royal Women's Hospital. Researchers used cutting edge-technology, electrical impedance tomography (EIT), where a small silk belt is placed around the infants chest to take highly detailed images deep into the lungs without interfering with parental contact or clinical care. This process allowed the team to generate high resolution images of how air was moving through the lungs for each breath.

Associate Professor Tingay said the technology helped babies in a way that was not possible before.

"Respiratory problems are the most common reason we need to treat babies in intensive care," he said. "This new technology not only allows us to see deep into the lungs but is also the only method we have of continuously imaging the lungs without using radiation or interrupting life-saving care. This study has shown that babies' lungs are far more complicated than traditional monitoring methods had previously suggested."

Associate Professor Tingay said he was currently researching whether using the technology on very preterm babies may help to predict which children would go onto develop lung problems.

Joanna Bezette's daughter, Camilla 'Milly', 14 months, has chronic lung disease after being born at 25 weeks.

"Milly had to be intubated at just eight minutes old," she said. "She spent the next five months in the neonatal intensive care unit relying on various types of respiratory ventilation and having what felt like an endless amount of X-rays. There were times when she had two or three X-rays a day. You just shudder to think of a tiny baby having to go through that.

"It took doctors about a month to get a full picture of just how little and underdeveloped Milly's lungs were. Even today Milly still requires supplementary oxygen when sleeping."

Ms Bezette said it was remarkable to think about the potential of the new lung imaging technology for premmie babies.

"So many families could be spared in future from what we went through in those first few weeks of Milly's life," she said. "To have imaging technology that can detect quickly whether there is problem with a newborn's lungs and that's also not invasive will be of such great comfort."

Associate Professor Tingay said this recent study provided the first detailed description of exactly how lungs fill with air during the first moments after birth.

"Healthy term babies use remarkably complex methods of adapting to air-breathing at birth," he said. "There is a reason why parents, midwives and obstetricians are pleased to hear those first life-affirming cries when a baby is born. Crying is a process that quickly aerates the lung, which is why 80 per cent of all breaths immediately after birth are cries.

"We were amazed to see that expiration is also critically important during those first cries. Just after birth the lung is still at risk of collapsing and the air-spaces can refill with fluid when a baby is breathing out. Babies are remarkably clever, as they breath out after a cry they move gas from well aerated regions to those areas of the lungs that are still filled with fluid preventing collapse. Babies will keep doing this until their lungs are safely filled with air and then they can start breathing normally."

Associate Professor Tingay said doctors lacked strong evidence-based interventions to support breathing after birth, influencing infant deaths, the rate of disease and resource allocation across all health care settings.

"Improving interventions in the delivery room first requires understanding the processes that define success and failure of breathing at birth," he said. "This study has significantly reduced that knowledge gap. We hope that being able to see these unique breathing patterns in the delivery room will tell clinicians when a baby needs resuscitation and also guide how effective that resuscitation is."

Green tea supplements modulate facial development of children with Down syndrome
A new study led by Belgian and Spanish researchers published in Scientific Reports adds evidence about the potential benefits of green tea extracts in Down syndrome. The researchers observed that the intake of green tea extracts can reduce facial dysmorphology in children with Down syndrome when taken during the first three years of life. Additional experimental research in mice confirmed the positive effects at low doses. However, they also found that high doses of the extract can disrupt facial and bone development. More research is needed to fully understand the effects of green tea extracts and therefore they should always be taken under medical supervision.

Down syndrome is caused by the presence of a third copy of chromosome 21, leading to an overexpression of the genes in this region and resulting in a number of physical and intellectual disabilities. One of the genes, DYRK1A, contributes to altering brain and bone development in people with Down syndrome. The green tea compound EGCG (epigallocatechin-3-gallate) is known to inhibit DYRK1A activity, although it also has other mechanisms of action. Previous research has shown the potential of EGCG to improve cognition in young adults with Down syndrome.

In a new study, researchers analysed the effect of green tea supplements on facial development in Down syndrome. In the experimental part of the study, the EGCG supplements were tested in mice at different dosages. In a second part of the research, they did an observational study on children with and without Down syndrome. This work, led by the Centre for Genomic Regulation (CRG), European Molecular Biology Laboratory (EMBL) and University of Barcelona in Spain and KU Leuven in Belgium, is an international effort involving researchers from University of Central Florida, La Salle - University Ramon Llull, and IMIM - Hospital del Mar Medical Research Institute.

For the mouse study, carried out at KU Leuven, the researchers started the treatment before birth, while the pups were developing in the wombs of their mothers, by adding either a low or a high dose of green tea extracts to their drinking water. "The low dose treatment had a positive effect on mice that are a model of Down syndrome," Professor Greetje Vande Velde (KU Leuven) comments, co-lead author of the study. "Sixty percent of them showed a facial shape similar to the control group."

"The high dose treatment, however, generated very mixed results, and even disrupted normal facial development in some cases, causing additional dysmorphology. This occurred in all mice, in the model of Down syndrome as well as in the control group."

Age-dependent effects

The observational study was set up in Spain and also included participants from North America. 287 children between 0 and 18 years participated, including children with Down syndrome who did (n = 13) or didn't (n = 63) receive EGCG supplementation. The treated group were all self-medicated and didn't follow a prescribed protocol.

"All participants were photographed from various angles to create a 3D model of their faces," explains Neus Martínez-Abadías, professor at the University of Barcelona and co-lead author of the study. "We use 21 facial landmarks, and the distances between them, to compare the faces of the participants. In the youngest group between 0 and 3 years, we observed that 57 percent of the linear distances are significantly different when you compare the faces of children with Down syndrome that never received the treatment to those of children that do not have Down syndrome. For babies and toddlers who did receive EGCG treatment, this difference was much smaller, only 25 percent. After green tea supplementation, the facial dysmorphology decreases and the children with or without Down syndrome look more alike."

"We didn't identify a similar effect in the adolescent group. Even when treated with green tea extracts, children with Down syndrome still show a difference of more than 50 percent compared to the control group. These findings suggest that the green tea supplements only affect facial development when they are administered in the early stages of life when the face and skull are rapidly growing."

Further research required

"Despite the potential benefits we observed, we must handle these findings with caution considering they are preliminary and based on an observational study," Professor Vande Velde warns. "Much more research is necessary to evaluate the effects of EGCG-containing supplements, the appropriate dose and their therapeutic potential in general. We also need to take into the account possible effects on other organs and systems, not just on the development of the face. This requires first more basic research in the lab with mice, and then clinical studies with more participants and controlled use of these supplements."

"Our findings suggest that effects of EGCG strongly depend on the dose." Professor Martínez-Abadías concludes. "EGCG products are commercially available and they are used regularly as a general health-promoting compounds. However, it's important to follow the European Food Safety Authority recommendations regarding the maximal intake and to always consult a physician before taking the supplements. Our research shows potential beneficial effects of facial development at low doses, but at very high doses they can produce unpredictable effects in mice. More research is needed in humans to determine the optimal dose at each age that maximizes the potential benefits."

The models used to produce global climate scenarios may overestimate the energy and emission savings from improved energy efficiency, warns new research led by academics at the University of Sussex Business School and the University of Leeds.

In a review of 33 studies, the researchers find that economy wide rebound effects may erode around half of the energy and emission savings from improved energy efficiency.

These rebound effects result from individuals and businesses responding to the benefits of improved energy efficiency - such as cheaper heating, lighting and travel. These responses improve quality-of-life, raise productivity and boost industrial competitiveness, but they also reduce the economy-wide energy savings.

The new study argues that economy-wide rebound effects are larger than commonly assumed, which may partly explain the close links between energy consumption and GDP over the past 100 years.

Improved energy efficiency is expected to play a central role in meeting the goals of the Paris Agreement, contributing up to 40% of the envisaged reductions in global greenhouse gas (GHG) emissions over the next two decades.

However, the new research suggests that the models used by the Intergovernmental Panel on Climate Change (IPCC), the International Energy Agency (IEA) and others fail to adequately capture these rebound effects. As a result, their scenarios may underestimate future global energy demand. In the absence of policies to mitigate rebound effects, this could make the Paris Agreement targets harder to achieve.

The authors argue that global energy modellers need to take rebound effects more seriously, and to find ways of capturing the full range of effects within their scenarios. They also recommend the use of carbon pricing to limit rebound effects and the targeting of energy efficiency policies to maximise their economic and environmental benefits.

Steve Sorrell, Professor of Energy Policy in the Science Policy Research Unit (SPRU) at the University of Sussex Business School, said: "Rebound effects are notoriously difficult to estimate, but our understanding has improved enormously over the last decade. What we show here is that 33 studies from different countries using very different methodologies all reach broadly the same conclusion - namely that economy-wide rebound effects are large. Unfortunately, the models we rely upon to produce global energy and climate scenarios do not adequately capture these effects. This needs to change."

Dr Paul Brockway, University Academic Fellow in the School of Earth and Environment at the University of Leeds, said: "If global energy use is higher than we expect, we may need to place more reliance on low-carbon energy supply and negative emission technologies to meet our climate goals. This will require political will, ambitious policies, large-scale investment, extensive land use, and crucially, significant lead times. We therefore need to take rebound effects seriously - and to find ways to maximise energy savings whilst continuing to improve quality-of-life."

In a new paper published today in Renewable and Sustainable Energy Reviews, the researchers find that many of the global energy scenarios that meet the Paris Agreement goals anticipate little or no growth in global energy demand despite continued growth in incomes.

However, there is little precedent for such significant 'decoupling' of energy consumption from GDP. Only a small number of countries have managed to grow their economies whilst reducing energy use, and then for only short periods of time. Current global trends are in the opposite direction with global energy consumption rising rapidly in the years prior to the Covid pandemic.

The team of researchers, comprising academics from the University of Leeds, University of Sussex, University of Massachusetts Amhurst, Calvin University, IFP Energies Nouvelles and Institut Louis Bachelier, reviewed 21 studies that used macroeconomic models to estimate the economy-wide rebound effects from a variety of energy efficiency improvements in different countries and sectors.

They found that 13 of the 21 studies using a common approach of 'computable general equilibrium' modelling estimated rebound effects of 50% or more - implying that over half the potential energy savings were 'taken back' by various economic and behavioural responses. The mean estimate of rebound effects from these studies was 58% and the median estimate was 55%, with some studies finding that the energy savings were eliminated altogether.

The team also reviewed 12 other studies that used a variety of other methods to estimate economy-wide rebound effects, and found these gave an even larger mean estimate of 71%.

The team then reviewed four of the 'integrated assessment models' used by the IPCC, together with the global energy models used by bp, Shell, the International Energy Agency (IEA) and the US Energy Information Administration (EIA). They found that most of these models only captured some of the mechanisms contributing to rebound effects, or included them in a simplified manner. Moreover, in some cases the process of calibrating scenarios largely precluded the investigation of rebound effects.

Dr Gregor Semieniuk, Assistant Research Professor at the University of Massachusetts Amherst, said: "Global energy models risk overestimating the potential for energy savings if they do not fully account for the multiple channels of the economy wide rebound. Nearly all the scenarios for keeping global temperature increase to a manageable level rely on heavily improved energy efficiency so understanding the potential for rebound - and what mitigates it - is critical. Now is the time to re-examine rebounds in global climate scenarios to ensure that our expectations for energy savings are well-founded."

Professor Christiani Jeyakumar Henry, Senior Advisor of Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR) and his team have developed a Glycaemic Index (GI) glossary of non-Western foods. The research paper was published in Nutrition & Diabetes on 6 Jan 2021: https://doi.org/10.1038/s41387-020-00145-w.

Observational studies have shown that the consumption of low glycaemic index (GI) foods is associated with a lower risk of type 2 diabetes mellitus (T2DM), significantly less insulin resistance and a lower prevalence of the metabolic syndrome. However, most published GI values focus on Western foods with minimal inclusion of other foods from non-Western countries, hence their application is of limited global use.

The team's comprehensive study provides the GI values for a variety of foods that are consumed in non-Western countries, such as Singapore, Malaysia, Thailand, India, China, Japan, South Korea, Middle East and more. The review extends and expands on the current GI tables to widen its application globally. The GI data compiled consists of both single and mixed meals. This is a major advance to many GI tables that have focused on single foods. Mixed meals in Asia are complex in relation to ingredients used and taste. Given the complexity, the inclusion of the GI of mixed meals is a major advantage. It is hoped that this compendium will highlight ways to reduce the GI of carbohydrate-rich staples and enhance the use of GI tables for a worldwide audience.

Targeted, efficient and with few side effects: A new method for combating periodontitis could render the use of broad-spectrum antibiotics superfluous. It was developed and tested for the first time by a team from Martin Luther University Halle-Wittenberg (MLU), the Fraunhofer Institute for Cell Therapy and Immunology IZI and Periotrap Pharmaceuticals GmbH. The aim is to neutralise only bacteria that cause periodontitis while sparing harmless bacteria. The study appeared in the Journal of Biological Chemistry.

Periodontitis is a common bacterial inflammation of the gums. According to the World Health Organization WHO Oral Health Study, almost 10 percent of the global population are affected with a severe form of the disease, which can lead to tooth loss as well as increasing the risk of other diseases, such as Alzheimer's and cardiovascular disease. Until now, treatment has mainly involved the use of broad-spectrum antibiotics that attack all bacteria in the mouth. However, this has some disadvantages: "One side effect of the treatment is that it also destroys all the harmless or beneficial bacteria in the oral cavity. In addition, the bacteria can ultimately develop resistance to the antibiotics," explains Dr Mirko Buchholz from Periotrap Pharmaceuticals, who led the new study alongside Professor Milton T. Stubbs, a biotechnologist at MLU.

The researchers therefore looked for a way to eradicate only the harmful bacteria in the mouth. A team from Fraunhofer IZI's Department of Drug Design and Target Validation in Halle developed a test substance that attacks glutaminyl cyclase, a specific enzyme in the bacteria that plays a special role in metabolism. Inactivation of this enzyme harms the bacteria and, ideally, no periodontitis can develop. To test its effectiveness, the researchers joined forces with the Clinics for Dental Medicine at the University of Bern, Jagiellonian University in Krakow and the University of Louisville in Kentucky (USA). They found that the new substance successfully suppresses the growth of pathogenic bacteria.

The new test substance has a special feature: It only works on the harmful bacteria. "Our target, glutaminyl cyclase, comes in two different variants. Normally, plants and bacteria have one variant of the enzyme and mammals another. The two variants work in a similar fashion, but they differ significantly in their structure. It's a bit like flat-tip versus Phillips screwdrivers," explains Stubbs. Surprisingly, the bacteria that trigger periodontitis have the mammalian variant of the enzyme. "This is crucial for our approach because it gives us a possible target so we only kill the pathogenic bacteria and leave the harmless ones intact," says Mirko Buchholz. To minimise possible side effects in advance, the team compared the bacterial enzyme with the human variant. "There are small but significant differences between the enzymes," says Stubbs. These differences are probably sufficient for the new substance to not affect the human enzymes. Therefore, only minor side effects are to be expected.

The researchers' study provides initial evidence that the approach essentially works. It must now be fine-tuned in further studies and tested in subsequent clinical trials. It may therefore take some years before the research from Halle becomes a marketable drug.

A variant of SARS-CoV-2 that emerged in southeast England in November 2020 is more transmissible than pre-existing variants, a new modeling study finds. Further analyses suggest the variant - VOC 202012/01 - will lead to large resurgences of COVID-19 cases. "Without stringent control measures, including limited closure of educational institutions and a greatly accelerated vaccine roll-out, COVID-19 hospitalizations and deaths across England in 2021 will exceed those in 2020," the study's authors say. After emerging in November 2020, evidence began to emerge in December that VOC 202012/01 was rapidly outcompeting preexisting variants in southeast England. As of 15 February 2021, it comprises roughly 95% of new SARS-CoV-2 infections in England and has now been identified in at least 82 countries. Estimates of its growth rate, disease severity, and impact are crucial for informing policy responses. After analyzing 150,000 sequenced SARS-CoV-2 samples from across the United Kingdom, Nicholas Davies and colleagues found that the relative population growth rate of VOC 202012/01 in the first 31 days following its initial observation was higher than that of all 307 other virus variant lineages. To understand possible biological mechanisms for this, the authors used an age- and regionally structured mathematical model of SARS-CoV-2 transmission to test several assumptions, including that the variant has a higher viral load or longer shedding period. Based on their analysis, they identify increased transmissibility as the model that best explains the variant's rapid spread. They estimate that the novel variant has a 43-90% higher reproduction number than preexisting variants of SARS-CoV-2 in England. Davies and colleagues used modeling to further analyze how interventions could reduce the potential burden of this new variant in the United Kingdom. From the scenarios they assessed, they conclude that a substantially increased vaccine roll-out and school closures for 2021 may be needed to prevent COVID-19 deaths and hospitalizations in 2021 from exceeding those in 2020. The authors note limitations to their analysis, including having only considered a small number of intervention and vaccination scenarios. Even so, they conclude, their projections point to "an urgent need to consider what new approaches may be required to sufficiently reduce the ongoing transmission of SARS-CoV-2."

In an analysis of nationwide data from the Veterans Health Administration, approximately one-quarter of individuals with kidney stones had a diagnosis of osteoporosis or bone fracture around the time of their kidney stone diagnosis. The findings are published in the Journal of Bone and Mineral Research.

Investigators identified 531,431 patients with kidney stone disease between 2007 and 2015, and they found that 23.6% of patients had a diagnosis of osteoporosis or fracture around the time of their kidney stone diagnosis. In patients with no prior history of osteoporosis or bone analyses before their kidney stone diagnosis, 9.1% received a bone density scan after a kidney stone diagnosis, of whom 20% were subsequently diagnosed with osteoporosis.

The findings provide support for wider use of bone density screening in individuals with kidney stones, including middle-aged and older men who may not be recognized as at-risk for osteoporosis or fracture.

"We hope this work raises awareness regarding the possibility of reduced bone strength in patients with kidney stones. In our future work, we hope to identify which patients with kidney stones are at higher risk for osteoporosis or fracture to help guide bone density screening efforts by clinicians in this population," said lead author Calyani Ganesan, MD, of Stanford University.

Patients with dementia may benefit from being referred to specialist palliative care--a branch of medicine that focuses on optimizing quality of life and providing relief from symptoms--but who should be referred, and when? A recent analysis of published studies on the topic found a lack of consensus regarding referral criteria for palliative care in patients with dementia. The results are published in the Journal of the American Geriatrics Society.

The analysis identified a wide array of reasons for referring patients with dementia to specialist palliative care, broadly classified under 13 themes. The diversity highlights the many reasons to involve specialist palliative care and simultaneously the lack of consensus on when patients should be referred.

"Given the growing recognition of unmet supportive and palliative care needs in patients with dementia, a set of consensual referral criteria may facilitate timely specialist palliative care referral to enhance patient and caregiver outcomes," said senior author David Hui, MD, MSc, of the University of Texas MD Anderson Cancer Center.

Students have diverse reasons for dropping out of colleges and universities without obtaining a degree. A new study published in the European Journal of Education provides a detailed analysis of these reasons.

The study found that the most important reasons for leaving university without a degree are mainly related to students' lack of interest in their field of study, as well as wrong expectations concerning the content of their studies. Problems related to students' academic performance also appear to be important.

The study suggests potential counter measures that higher education institutions might use to help students at risk of dropping out as they strive to finish their education and obtain their degrees.

"The phenomenon of university dropout is a very relevant issue, and it's extremely important for the society, for higher education institutions, and of course, for the students themselves. It's associated with an inefficient use of universities' resources, personal failure, wasted time, and monetary investments," said co-author Hervé D. Teguim Kamdjou, MSc, of the University of Duisburg-Essen, in Germany. "Providing new insights into this issue will help universities implement early warning systems and more personalised counselling services to support students at risk of dropping out during an early stage of study."

How have travel restrictions and reduced tourism in response to the COVID-19 pandemic affected mammals in different tourist destinations? Researchers recently reviewed published studies and news stories to consider this question. Their findings are published in Mammal Review.

The authors noted that whether the pandemic has affected mammals positively or negatively is difficult to determine--their findings showed that effects of reduced tourism varied by species and the contexts that they are in.

For example, some mammals in zoos thrived in the absence of visitors while others appeared to be deprived of enrichment without tourists. Also, the pandemic brought hunger to some mammals that had been offered food by tourists, and the absence of tourism may have put some animals in protected areas in danger of being poached. On the other hand, marine mammals have reportedly returned to environments that were too polluted and disturbed to live in before the pandemic but now provide suitable habitat.

During their seasonal migration, birds typically travel between breeding and non-breeding grounds along migratory routes grouped into major flyways, such as the Indo-European flyway between Europe and the Indian subcontinent. In a new study published in the Journal of Biogeography, investigators used modelling and tracking techniques to identify potential migratory barriers and corridors within the Indo-European flyway, as well as birds' adaptive behaviors that help with navigation along the route.

"For me, the study started years ago on the coast of the German Baltic Sea. Together with two of my co-authors Roland Neumann and Benjamin Metzger, we caught and tracked Common rosefinches aiming to reveal their exact wintering locations," said lead author Simeon Lisovski, PhD, of the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, in Germany. "Years later, we found out that other researchers from across Europe did the same and that putting the tracks in perspective can yield more in-depth ecological insights than each single study could provide. Merging these tracks with flyway-wide datasets on climate and habitat has been a super insightful and exciting collaborative experience."

Even during the COVID-19 pandemic, opioid misuse has continued unabated in the United States, with an estimated 2.5 million or more Americans suffering from opioid use disorder. Most people treated for the disorder are given medications, such as buprenorphine, that activate opioid receptors. But there is disagreement about whether it's safe to prescribe buprenorphine for people who also take benzodiazepines, which are potentially addictive medications prescribed for stress, sleep and anxiety.

New research involving the medical data of more than 23,000 patients being treated for opioid use disorder supports the use of buprenorphine in patients also taking benzodiazepines. Researchers at Washington University School of Medicine in St. Louis found that the drug can protect opioid users from overdosing, even when such patients also take benzodiazepines, such as Valium, Xanax and Ativan.

The study is published online March 3 in The American Journal of Psychiatry.

"Buprenorphine has had very good results as a treatment for opioid use disorder, partly because patients can take the drug at home, which is different from other drugs commonly used to treat the disorder such as methadone, which requires visits to clinics," said first author Kevin Xu, MD, a resident physician in the Department of Psychiatry. "It's well known that buprenorphine saves lives in patients with opioid use disorder, but because the drug has central nervous system depressing effects, there have been big questions about safety when patients also take benzodiazepines, which also depress the central nervous system. Our findings, however, indicate that buprenorphine makes overdose less likely, even in people also taking benzodiazepines."

The research team dug into the topic partly because many treatment centers do not accept patients who are addicted to opioids and also take prescription benzodiazepines.

"Up to a third of people who suffer opioid overdoses also have benzodiazepines in their systems," Xu said. "Many people get turned away from buprenorphine treatment or, even worse, their doctors abruptly taper them off benzodiazepines, which can be very destabilizing. Our goal was to learn more about whether there are dangers associated with taking buprenorphine while also taking benzodiazepines."

Although buprenorphine isn't the only medication used to treat opioid use disorder -- others include methadone and naltrexone -- the researchers focused on buprenorphine in this study because patients often can fill prescriptions for the medication at a pharmacy and take the drug at home.

Xu and his colleagues -- including Laura J. Bierut, MD, the Alumni Endowed Professor of Psychiatry, and Richard A. Grucza, PhD, a professor in the Department of Family and Community Medicine at Saint Louis University -- analyzed data compiled by insurance companies that tracked emergency room visits involving 23,036 de-identified patients with buprenorphine prescriptions.

"We've all heard about the devastation caused by opioids such as heroin and fentanyl, but use of benzodiazepines also can be addictive and deadly," said Bierut, one of the study's senior investigators. "Many people who are addicted to opioids also have anxiety or depression for which they've been prescribed a benzodiazepine drug. How to handle that combination has confounded psychiatrists and addiction medicine specialists, but we think these findings provide some clarity."

Every de-identified patient tracked in the database had experienced at least one overdose event, but none suffered a fatal overdose. Each individual was followed for two years to track what prescriptions they filled and how often each person ended up in the emergency department with a drug-related poisoning. Although the database tracked only nonfatal overdoses, Xu explained those events account for the vast majority of drug-related poisonings, adding that those who suffer nonfatal overdoses are at risk to eventually die of a drug overdose.

"These are high-risk patients, and we know that when someone overdoses once, it's likely he or she will be back in an emergency department again for the same reason," Xu said.

In trying to learn whether buprenorphine helped prevent overdoses and whether taking that drug along with benzodiazepines might increase overdose risk, the researchers discovered that opioid users who took buprenorphine had a 40% reduction in their risk for an overdose compared with not receiving the treatment. Meanwhile, opioid users with benzodiazepine prescriptions who did not take buprenorphine were almost twice as likely to suffer an overdose that put them in the hospital.

"Even for people taking benzodiazepines, buprenorphine had a protective effect," Xu said. "Buprenorphine didn't protect those patients from overdose as much as it protected users not taking benzodiazepines, but it still made overdoses less likely."

What that means about drug interactions between buprenorphine, opioids and benzodiazepines still isn't completely clear. But what is clear, Xu said, is that prescribing buprenorphine for opioid users in treatment can protect them from overdose, even if they also are taking a benzodiazepine drug.