Culture

Understanding how COVID-19 affects children vital to slowing pandemic, doctors say

image: Steven L. Zeichner, MD, PhD, is the head of UVA Health's Division of Pediatric Infectious Diseases.

Image: 
Sanjay Suchak | UVA Communications

Though COVID-19 so far appears to be largely sparing children, researchers are cautioning that it is critical to understand how the virus affects kids to model the pandemic accurately, limit the disease's spread and ensure the youngest patients get the care they need.

The warning comes from Steven L. Zeichner, MD, PhD, the head of UVA Health's Division of Pediatric Infectious Diseases, and Andrea T. Cruz, MD, MPH, a pediatric emergency medicine physician at Houston's Baylor College of Medicine. They have authored a commentary in the journal Pediatrics accompanying a new article that reveals a small percentage of infected children become seriously ill. Those at greatest risk include babies and preschoolers.

"Many infectious diseases affect children differently than adults and understanding those differences can yield important insights," the commentary authors write. "This will likely be true for COVID-19, just as it was for older infectious diseases."

Assessing COVID-19 Risks

Zeichner and Cruz note that there are subgroups of children who appear to be at greater risk of COVID-19 complications, particularly those who are younger, immunocompromised or have other pulmonary health problems.

However, the presence of other viral infections in up to two-thirds of childhood coronavirus cases makes it very difficult to assess the true effect of COVID-19 on children, they state. (This figure is based on prior studies of children with coronaviruses detectable in the respiratory tract.)

While much remains unknown, Cruz and Zeichner caution that children, even asymptomatic children, could play a "major role" in disease transmission. For example, they cite a study that found the virus remained in children's stool for several weeks after diagnosis. That, combined with other routes of transmission such as nasal secretions, could pose a major challenge for schools, day care centers and the children's families, they note.

"Since many children infected with COVID-19 appear to have have mild symptoms, or even no symptoms at all, it is important to practice all the social distancing, hygiene and other precautions being recommended by public health authorities to minimize transmission from children to others, including family members who may be at greater risk from the infection, such as grandparents or family members with chronic medical conditions," said Zeichner, who is working on innovative potential COVID-19 vaccines in his lab. "In addition, studies of the reasons why children are affected differently than adults by the infection may yield insights that can be helpful in understanding the disease and ways to treat or prevent it."

Credit: 
University of Virginia Health System

Social policies might not only improve economic well-being, but also health

March 19, 2020 -- A comprehensive review of U.S. social policies evaluated for their health outcomes found suggestive evidence that early life, income, and health insurance interventions have the potential to improve health. Scientists have long known that "social" risk factors, like poverty, are correlated with health. However, until this study, there was little research carried out to understand whether it was actually possible to improve population health by addressing these risk factors with social policies. The findings are published in The Milbank Quarterly, a multidisciplinary journal of population health and health policy published by the Milbank Memorial Fund.

"Since the 1960s, a large number of social policies that have been experimentally evaluated include health outcomes, but these were mostly overlooked. By tracking down these studies, we found a unique opportunity to inform evidence-based policymaking. It was sitting right there in front of us this whole time," said Peter Muennig, MD, a professor of Health Policy and Management at the Mailman School of Public Health at Columbia University. "Our goal was to conduct a comprehensive review of experimental studies of social and economic interventions that were not explicitly designed for the purpose of improving the health of participants. Health outcomes were often added as an afterthought and were overlooked." He added, "This is remarkable given the magnitude of expenditures in the nonmedical determinants of health in the United States and the weak evidence base supporting these investments."

The systematic review of all known randomized social experiments in the United States that involved health outcomes included 5,876 papers, reports, and data sources, ultimately encompassing 60 papers, reports, or datasets from 38 randomized social experiments. These experiments spanned the period 1962-2018 and featured a range of policies, analytic approaches, and target groups and measured a wide variety of health outcomes.

The final analysis was based on a sample of 450 unique health estimates across the 38 interventions. Of these, 77% were not able to reliably detect health outcomes because the sample was too small. Among those from which reliable estimates could be obtained, 49% demonstrated a significant health improvement, 44% had no effect on health, and 7% were associated with significant worsening of health. The most commonly reported outcome was mental health.

Eleven of the studies included tested interventions in the domain of early life and education. Nine of the included studies examined the social and health impacts of income maintenance and supplementation programs. Twelve of the included studies focused on employment and welfare-to-work: team-based supported employment, job training programs, employment support services.

The researchers found that early life and education interventions were associated with an 8% reduction in smoking. "Although this is a fairly small percentage, it could have wide implications and may be a proxy for other forms of risk-taking behaviors, such as condom or seatbelt use" noted Emilie Courtin, PhD, a fellow at Harvard University.

Income support and health insurance programs showed the most promise in improving population health. For a very small number of studies, harmful effects of social policies on health were indicated. These were mainly concentrated among time-limited welfare-to-work interventions.

The researchers point out that interventions in the domains of early life and education, income, and health insurance are particularly promising as population health policies. While many experiments were at high risk of bias, the research--all based on the "gold standard" randomized, controlled trial, gives us confidence that income support programs save lives.

Still, some studies that should have been able to measure health outcomes showed no health impact. This may indicate that they were true negative findings--and that health care providers and insurers should not randomly invest in social policies and expect health benefits, noted Muennig.

"Our study is exciting because it shows for the first time that it is possible for the government to improve health by making investments outside of the health system. The strong investments made by peer nations in welfare may explain why they have left the United States in the dust with respect to health and longevity. Still, policymakers need to be careful about how they make these investments, because they also have the potential to do harm."

Credit: 
Columbia University's Mailman School of Public Health

Improving success of giraffe translocations

image: According to a new study, giraffes should be translocated in groups of at least 30 females and 3 males to ensure long-term population success.

Image: 
Wild Nature Institute

Giraffes that are being translocated for conservation purposes should be moved in groups that contain at least 30 females and 3 males to ensure long-term population success. In two new studies, an international team of researchers identifies the ideal composition of a group to be moved and provides guidelines for all aspects of the translocation process, including decision-making and planning, transportation and monitoring of animals, and evaluation of success.

Giraffe populations declined by 40% between 1985 and 2015, according to the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. This led the IUCN to classify the species as vulnerable -- likely to become endangered unless circumstances change -- and some subspecies as endangered -- likely to become extinct in the immediate future.

"Translocations have been used as a conservation strategy to establish new populations, augment small or declining populations, or re-introduce the species to previously occupied areas," said Derek E. Lee, associate research professor of biology at Penn State and leader of the research team. "Translocations could be an important conservation tool for giraffes, but until now, there has been little guidance about how best to plan, implement, or report them."

The researchers used a modeling technique called a population viability analysis to determine the ideal size and sex distribution of a newly established population. They simulated a variety of scenarios to project long-term viability and genetic diversity -- which can buffer a population against disease and environmental change -- of founding populations. The researchers deemed a translocation scenario a success if there was a 95% probability that the population continued for 100 years while maintaining most of the original genetic diversity. They report their results in a paper published Feb. 27 in the journal Endangered Species Research.

A founding population of 30 females and 3 males resulted in long-term population viability, but to maintain more than 95% of the genetic diversity of the source population, groups of 50 females and 5 males are recommended. More females are required than males, because females, unlike males, provide care to young and are an important element of giraffe social structure.

"Small numbers of founders with fewer than ten females can appear to be successful in the first decades due to short-term population growth, but are not successful in the long-term," said Lee. "Small groups can suffer from inbreeding depression, and they are more likely to lose genetic diversity due to random events in the first years after translocation."

Because giraffes are physically difficult to move, they are often translocated as juveniles, which have higher rates of mortality than adults. A larger founding population can also buffer against the loss of young individuals.

"Most giraffe translocations in the past have moved too few animals to ensure the successful establishment of new population," said Lee. "Our recommendation of 30 to 50 females should greatly increase the success rate of future translocations that adhere to these rules."

The researchers provide additional guidelines about the translocation process in a paper published March 2 in the African Journal of Ecology. They reviewed documented cases of giraffe translocation and considered published accounts of giraffe biology and ecology as well as their personal experience.

The researchers describe how to set translocation goals and assess risk, including to the giraffes being moved, to the source population whose numbers are being reduced, and to other species--including humans--in the area of introduction. They explore how to select individuals and assess suitability of the new site and discuss how to transport animals, which the researchers stress should be performed by experts.

"Ongoing monitoring of the translocated population, adaptive management of the population, and documentation of the entire translocation process are also crucial, both for long-term success of the population and to improve future efforts," said Lee.

Credit: 
Penn State

'Feeling obligated' can impact relationships during social distancing

EAST LANSING, Mich. - In a time where many are practicing "social distancing" from the outside world, people are relying on their immediate social circles more than usual. Does a sense of obligation - from checking on parents to running an errand for an elderly neighbor - benefit or harm a relationship? A Michigan State University study found the sweet spot between keeping people together and dooming a relationship.

"We were looking to find whether obligation is all good or all bad," said William Chopik, assistant professor of psychology at MSU and co-author of the study. "When we started, we found that people were responding to types of obligations in different ways. People distinguished between requests that were massive obligations and requests that were simple. There's this point that obligation crosses over and starts to be harmful for relationships."

According to Jeewon Oh, MSU doctoral student and co-author of the study, obligation is sometimes the "glue that holds relationships together," but it often carries negative connotations.

"We found that some obligations were linked with greater depressive symptoms and slower increases in support from friends over time," Oh said. "However, other obligations were linked with both greater support and less strain from family and friends initially."

Chopik and Oh's findings suggest that there's a distinct point at which obligation pushes individuals to the brink of feeling burdened, which can start to harm their relationships.

"The line in our study is when it crosses over and starts to be either a massive financial burden or something that disrupts your day-to-day life," Chopik said. "While engaging in substantive obligation can benefit others and make someone feel helpful, it is still costly to a person's time, energy and money."

Until now, similar research showed inconsistencies in how obligation impacts relationships, which Chopik attributes to the spectrum of obligation. This spectrum ranges from light obligation, like keeping in touch with a friend, to substantive obligation, like lending that friend a considerable amount of money.

"In a way, major obligations violate the norms of friendships," Chopik said. "Interestingly, you don't see that violation as much in relationships with parents or spouses."

Chopik explained that friendships are viewed as low-investment, fun relationships that make people feel good.

"Our longest lasting friendships continue because we enjoy them. But if obligations pile up, it might compromise how close we feel to our friends," Chopik said. "Because friendships are a relationship of choice, people can distance themselves from friends more easily than other types of relationships when faced with burdensome obligations."

Additionally, substantive obligations may create strain in a friendship as we try to encourage our friends to do the same even when they might not be able to do so, Oh said.

"Although we may feel good when we do things for our friends, and our friends are grateful to us, we may start to feel like we are investing too much in that relationship," Oh said.

On the other end of the spectrum, light obligation creates what Chopik calls a "norm of reciprocity."

"Those light obligations make us feel better, make us happier and make our relationships stronger," Chopik said. "There's a sense that 'we're both in this together and that we've both invested something in the relationship.'"

That's why, among the best relationships, low-level acts of obligation don't feel like obligations at all. Small acts of kindness, which strengthen the bonds of our relationships, are done without any fuss or burden.

Still, some types of relationships can make even minor obligations seem daunting. If someone doesn't have a great relationship with a parent, a quick phone call to check in isn't enjoyable, it's an encumbrance.

"Even for things we would expect family members to do, some in the study did them begrudgingly," Chopik said.

Chopik and Oh's findings reveal a spectrum of obligations as diverse as the relationships one has in life.

"It's the little things you do that can really enhance a friendship, but asking too much of a friend can damage your relationship," Chopik said.

Credit: 
Michigan State University

New contrast agent for early diagnosis of brain metastases

image: Margitta Dathe, Leif Schröder, and co-workers demonstrate an MRI contrast agent that uses the available magnetization in a highly efficient way to enable selective cell labeling at minimally invasive concentrations.

Image: 
Barth van Rossum, FMP

A group of researchers led by Leif Schroeder from the Leibniz-Forschungsinstitut fuer Molekulare Pharmakologie (FMP) have found a way to detect metastases in certain types of cancer in the brain at an early stage, using only minimal amounts of contrast agent. To this end, the team uses a synthetic molecule that helps to detect the formation of new blood vessels, producing much more sophisticated imaging than is possible with conventional methods of diagnosis. The results have now been published in Advanced Biosystems.

Some types of cancer - including breast cancer - may induce the formation of brain metastases. Increased development of new small blood vessels (capillaries) is an early sign of abnormal tissue changes. Conventional contrast agents used in magnetic resonance imaging (MRI) for examining the brain are not suitable for the direct and early detection of newly forming cells. "For this, we need a contrast agent that considerably increases the sensitivity of MRI by greatly improving the contrast structure, and that is only needed in tiny amounts," explained FMP researcher Dr. Leif Schroeder.

His group has been working for a long time to develop new contrast agents that detect artificially magnetized xenon in tissue and that cause signals even in small quantities. In his efforts to create a contrast agent especially suited for use in vascular cells of the so-called blood-brain barrier, the physicist was able to draw on preliminary work undertaken by his FMP colleague Dr. Margitta Dathe, who had developed a similar structure for drug transport to these cells in inner vascular walls of the brain. This peptide structure forms so-called micelles, aggregates of around 19 molecules that cluster spontaneously.

To utilize micelles for diagnostic purposes, Schroeder and his team had them modified: "We inserted molecular cages - synthetic molecules shaped like a hollow soccer ball - that we can temporarily fill with xenon. We were therefore able to 'switch on' 19 xenon loads per micelle for the image contrast, enabling us to directly visualize this type of tumor-forming cells," reported Leif Schroeder.

First, he and his team tested whether the modified version of the structure developed by Margitta Dathe would still form micelles. "Fortunately, the molecules behaved in the same way, despite the insertion of cages, and formed micelles composed of 19 units each," the researcher remarked. The micelles were then supposed to interact with large amounts of xenon.

Having a high local density of cages is a prerequisite for visualizing blood vessel cells in MRI. In a further step, the researchers tested whether xenon could enter the cages inside the molecules - this also proved successful. Schroeder then investigated how micelles equipped with xenon behave in two cell cultures, one of which comprised cerebral cells. In this case, the micelles docked onto blood vessel cells and labeled them - the newly developed contrast agent worked. To check their findings, Leif Schroeder also tested the micelles in aortic cells. Since this type of cell is structured differently, however, there was much less binding of micelles in this case.

The advantage of the new method is that the spread of malignant tumors to the brain can be detected early, before the onset of widespread metastasis. This is because, when metastasis occurs, brain areas exhibit increased formation of blood vessels, which are needed to supply nutrients to tumor tissue. In the case of breast cancer, this type of metastasis is often associated with a poor prognosis. Blood vessels absorb the micelles developed by Schroeder's and Dathe's team, and xenon enables the process of new vessel formation to be visualized directly - at an early stage. Conventional methods for labeling certain cells for MRI are much less sensitive. A comparison showed that alternatives involving fluorine contrast agents are around 16,000 times less efficient.

"The new contrast agent could be used for the safe and minimally invasive detection of early-stage cerebral metastases. This could have significant advantages, particularly in the diagnosis of breast cancer, because dangerous tumors can be detected much earlier, improving therapy outcomes," summarized Leif Schroeder. In the future, Schroeder and his group intend to utilize xenon-based contrast agents for other medical applications.

Credit: 
Forschungsverbund Berlin

Compact beam steering studies to revolutionize autonomous navigation, AR, neuroscience

video: Blue optical phased array for augmented reality, trapped ion quantum computer and optogenetic neural stimulation.

Image: 
Myles Marshall, Secret Molecule, Min Chul Shin, Aseema Mohanty, Columbia Engineering

New York, NY--March 19, 2020--While beam steering systems have been used for many years for applications such as imaging, display, and optical trapping, they require bulky mechanical mirrors and are overly sensitive to vibrations. Compact optical phased arrays (OPAs), which change the angle of an optical beam by changing the beam's phase profile, are a promising new technology for many emerging applications. These include ultra-small solid-state LiDAR on autonomous vehicles, much smaller and lighter AR/VR displays, large-scale trapped-ion quantum computer to address ion qubits, and optogenetics, an emerging research field that uses light and genetic engineering to study the brain.

Long-range, high-performance OPAs require a large beam emission area densely packed with thousands of actively phase-controlled, power-hungry light-emitting elements. To date, such large-scale phased arrays, for LiDAR, have been impractical since the technologies in current use would have to operate at untenable electrical power levels.

Researchers led by Columbia Engineering Professor Michal Lipson have developed a low-power beam steering platform that is a non-mechanical, robust, and scalable approach to beam steering. The team is one of the first to demonstrate low-power large-scale optical phased array at near infrared and the first to demonstrate optical phased array technology on-chip at blue wavelength for autonomous navigation and augmented reality, respectively. In collaboration with Adam Kepecs' group at Washington University in St. Louis, the team has also developed an implantable photonic chip based on an optical switch array at blue wavelengths for precise optogenetic neural stimulation. The research has been recently published in three separate papers in Optica, Nature Biomedical Engineering, and Optics Letters.

"This new technology that enables our chip-based devices to point the beam anywhere we want opens the door wide for transforming a broad range of areas," says Lipson, Eugene Higgins Professor of Electrical Engineering and Professor of Applied Physics. "These include, for instance, the ability to make LiDAR devices as small as a credit card for a self-driving car, or a neural probe that controls micron scale beams to stimulate neurons for optogenetics neuroscience research, or a light delivery method to each individual ion in a system for general quantum manipulations and readout."

Lipson's team has designed a multi-pass platform that reduces the power consumption of an optical phase shifter while maintaining both its operation speed and broadband low loss for enabling scalable optical systems. They let the light signal recycle through the same phase shifter multiple times so that the total power consumption is reduced by the same factor it recycles. They demonstrated a silicon photonic phased array containing 512 actively controlled phase shifters and optical antenna, consuming very low power while performing 2D beam steering over a wide field of view. Their results are a significant advance towards building scalable phased arrays containing thousands of active elements.

Phased array devices were initially developed at larger electromagnetic wavelengths. By applying different phases at each antenna, researchers can form a very directional beam by designing constructive interference in one direction and destructive in other directions. In order to steer or turn the beam's direction, they can delay light in one emitter or shift a phase relative to another.

Current visible light applications for OPAs have been limited by bulky table-top devices that have a limited field of view due to their large pixel width. Previous OPA research done at the near-infrared wavelength, including work from the Lipson Nanophotonics Group, faced fabrication and material challenges in doing similar work at the visible wavelength.

"As the wavelength becomes smaller, the light becomes more sensitive to small changes such as fabrication errors," says Min Chul Shin, a PhD student in the Lipson group and co-lead author of the Optics Letter paper. "It also scatters more, resulting in higher loss if fabrication is not perfect--and fabrication can never be perfect."

It was only three years ago that Lipson's team showed a low-loss material platform by optimizing fabrication recipes with silicon nitride. They leveraged this platform to realize their new beam steering system in the visible wavelength--the first chip-scale phased array operating at blue wavelengths using a silicon nitride platform.

A major challenge for the researchers was working in the blue range, which has the smallest wavelength in the visible spectrum and scatters more than other colors because it travels as shorter, smaller waves. Another challenge in demonstrating a phased array in blue was that to achieve a wide angle, the team had to overcome the challenge of placing emitters half a wavelength apart or at least smaller than a wavelength--40 nm spacing, 2500 times smaller than human hair--which was very difficult to achieve. In addition, in order to make optical phased array useful for practical applications, they needed many emitters. Scaling this up to a large system would be extremely difficult.

"Not only is this fabrication really hard, but there would also be a lot of optical crosstalk with the waveguides that close," says Shin. "We can't have independent phase control plus we'd see all the light coupled to each other, not forming a directional beam."

Solving these issues for blue meant that the team could easily do this for red and green, which have longer wavelengths. "This wavelength range enables us to address new applications such as optogenetic neural stimulation," notes Aseema Mohanty, a postdoctoral research scientist and co-lead author of the Optics Letter and Nature Biomedical Engineering papers. "We used the same chip-scale technology to control an array of micron-scale beams to precisely probe neurons within the brain."

The team is now collaborating with Applied Physics Professor Nanfang Yu's group to optimize the electrical power consumption because low-power operation is crucial for lightweight head-mounted AR displays and optogenetics.

"We are very excited because we've basically designed a reconfigurable lens on a tiny chip on which we can steer the visible beam and change focus," explains Lipson. "We have an aperture where we can synthesize any visible pattern we want every few tens of microseconds. This requires no moving parts and could be achieved at chip-scale. Our new approach means that we'll be able to revolutionize augmented reality, optogenetics and many more technologies of the future."

Credit: 
Columbia University School of Engineering and Applied Science

How to slow down ageing?

image: Professor Pärt Peterson Photo: Andres Tennus/University of Tartu

Image: 
Andres Tennus/University of Tartu

Healthy ageing has become one of the priorities of research in Europe. University of Tartu researchers looked for differences in the immune systems of young and old people. They focused on monocytes and found that the monocytes of the elderly do not seem to produce as much energy, and there is an increase in inflammation markers compared to younger people. Looking into the future, this research gives food for thought as to how to slow down age-related changes.

White blood cells or leukocytes include many cells with various tasks. To get a better understanding of exactly what these cells do, they need to be observed separately. Therefore, researchers at the University of Tartu Institute of Biomedicine and Translational Medicine together with colleagues from Tartu University Hospital and Estonian Genome Centre studied a specific white blood cell type - monocytes.

Monocytes comprise about 5-10% of all white blood cells in human blood. As with all other leukocytes, they originate from the hematopoietic cells of bone marrow, but they have special properties which help them fight viruses and other pathogens. They are constantly changing through life together with general changes in the organism.

According to a professor of molecular immunology at the University of Tartu, Pärt Peterson, links between ageing and monocytes have been found before. "For example, they are known to be associated with inflammatory processes occurring in the body. A link between monocytes and vascular calcification or atherosclerosis is also known," said Peterson.

Vascular calcification means that, due to the deposition of dead cells, cholesterol, fatty acids and lipids, plaques are formed on the walls of arteries. Over years, these plaques become denser and make blood vessels narrower. As a result, blood flow in blood vessels becomes restricted. "Calcification is a long-term and complex change in the walls of blood vessels, but it is the monocytes that affect the inflammation originating from the walls of blood vessels and accumulate in atherosclerotic plaques," explained Peterson.

Primarily based on this background information, the researchers wanted to study which changes have occurred in the monocytes of young people, and which in the monocytes of the elderly. "We found that the expression of many genes varies in the monocytes of elderly people. Changes have mainly occurred in the genes related to protein synthesis and in the work of mitochondria, i.e. the power plants of cells. It might be said that the monocytes of older people do not seem to produce as much energy as the cells of younger people," noted the professor.

There was also a visible increase in the intracellular inflammation markers in older people, which is probably accompanied by a general increase in inflammation levels. There are also other intracellular metabolic changes, as a greater proportion of some lipids was noted in elderly people, for example. Many lipids are an important and natural part of cell membranes, but according to Peterson, this may lead to the idea that the excessive accumulation of lipidic compounds in monocytes may be related to the plaques forming on the walls of blood vessels, and thus to atherosclerosis.

"Time will show whether we will be able to do something to slow down age-related changes. This study at least gives an idea as to which direction we should look to next. In terms of the future, it would be a big achievement if we were able to postpone or even avoid the process of vascular calcification," said Peterson.

According to the scientist, new practical solutions will definitely be added in the future, taking into account that healthy ageing has become one of the priorities of research in Europe. Several European countries, including Denmark and the Netherlands, have already created specialised institutes and centres for solving the issues related to the ageing society.

Peterson noted that conducting such basic research studies in Estonia is convenient, because due to the small size of the country, we have very good contacts and cooperation possibilities, broad-based genetic data and great possibilities for developing digital health care.

Credit: 
Estonian Research Council

E-cigarette users had substances linked to bladder cancer in urine, review finds

CHAPEL HILL-- An analysis of evidence from multiple scientific studies found six substances that have a strong link to bladder cancer in the urine of people who had used electronic cigarettes and sometimes other tobacco products, researchers from the University of North Carolina Lineberger Comprehensive Cancer Center and NYU Langone Health reported.

In the study in the journal European Urology Oncology, researchers compiled the results of 22 different studies that analyzed the urine of people who used e-cigarettes or other tobacco products, including cigarettes, to check for evidence of cancer-linked compounds or biomarkers of those compounds. They found six biomarkers or compounds with a strong link to bladder cancer.

"Smoking is the No.1 modifiable behavioral risk factor for bladder cancer," said UNC Lineberger's Marc Bjurlin, DO, MSc, associate professor of urology in the UNC School of Medicine. "There is now evolving literature showing that people who vape may have similar carcinogens in their urine as combustible cigarette users."

While public health agencies including the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention have warned that there are health risks of vaping, including for e-cigarette-associated lung injury, their safety profile has not been "definitively characterized," according to Bjurlin and his colleagues.

"The first and foremost side effects that we're seeing from electronic cigarette use are lung and pulmonary related," Bjurlin said. "We won't see the side effects for these other kinds of carcinogenic pathways until much later down the exposure pipeline."

To develop a better understanding of the long-term risks of vaping, including cancer, researchers investigated possible exposure to substances that can cause bladder cancer in particular since carcinogens could be processed in the body and then passed in urine.

In their review, Bjurlin and his colleagues found 40 different parent compounds that can be processed in the body to produce 63 different toxic chemicals or carcinogenic metabolites, which are substances that remain after in the body after processing.

Six of those chemicals have a strong link to bladder cancer, according to researchers' analysis of carcinogens databases of the International Agency for Research on Cancer and the Collaborative on Health and the Environment Toxicant and Disease Database.

They found evidence in some studies that e-cigarette users had "significantly" higher levels of several carcinogens that can be metabolized into substances linked to bladder cancer in their urine compared to people who had never used them.

"This finding shows us that people who vape will be exposed to a variety of different carcinogens," Bjurlin said. "People who have decades of exposure to these carcinogens from vaping may be at risk for developing malignancies, especially bladder cancer."

There were several limitations to the study, including that researchers did not know the levels of all of the cancer-causing substances in the urine of users from the studies.

In addition, some studies included people who were "dual users," or people who both smoked and vaped e-cigarettes. There were also cases when users smoked cigarettes and switched to e-cigarettes.

"The study population was quite heterogeneous, meaning that often studies looked at dual users, meaning those who used e-cigarettes and combustible cigarettes," Bjurlin said. "That made it difficult to assess whether the carcinogen found in the urine was actually from the e-cigarette use or from the cigarette use."

Further research is needed, said Bjurlin, who wants to determine the threshold of exposure to carcinogens that would lead to development of bladder cancer or other cancer types. He plans to lead a study that will evaluate carcinogens in the urine of e-cigarette users, smokers and non-users.

"Although there is no definitive case yet linking bladder cancer to vaping, it may be reasonable to suspect that decades down the road after exposure to these byproducts, people who vape may be at risk of developing bladder cancer," he said.

Credit: 
UNC Lineberger Comprehensive Cancer Center

New drug combination passes safety test in pancreatic cancer

image: The only peer-reviewed open access journal focused solely on pancreatic cancer

Image: 
Mary Ann Liebert, Inc., publishers

New Rochelle, NY, March 19, 2020--A new study has shown a novel peptide antagonist, given in combination with a PD-1 inhibitor, to be safe and well-tolerated in patients with advanced, refractory pancreatic and rectal cancer. The highest dose tested had a good safety profile and was recommended for use in future patient trials, as reported in Journal of Pancreatic Cancer, a peer-reviewed open access publication from Mary Ann Liebert, Inc., publishers. Click here to read the full-text open access article free on the Journal of Pancreatic Cancer website.

"Safety and Pharmacokinetics of CXCR4 Peptide Antagonist, LY2510924, in Combination with Durvalumab in Advanced Refractory Solid Tumors" was coauthored by Mark O'Hara, MD, Abramson Cancer Center at the University of Pennsylvania, and colleagues from University of Colorado School of Medicine, The University of Chicago Medicine, Eli Lilly and Company, Astra Zeneca, and Washington University Medical School in St. Louis.

The purpose of this open label phase 1a study was to determine the maximum tolerated dose, safety, and tolerability of LY2510924, a CXCR4 peptide antagonist with proven, significant antitumor activity in preclinical studies, given in combination with the PD-1 inhibitor durvalumab. The study patients had advanced pancreatic or rectal cancer that did not respond to other treatment. Patients received 20, 30, or 40 mg of LY2510924 daily together with 1500 mg of durvalumab on day 1 of each 28-day cycle. No adverse events resulted in death or the need to discontinue treatment with any of the three doses, leading to the conclusion that the highest dose of LY2510924, 40 mg, daily is safe and well-tolerated and should be used in the next phase of studies. The researchers also reported that a best response of stable disease was seen in 44% of patients in the trial.

Journal of Pancreatic Cancer Editor-in-Chief Charles J. Yeo, MD, Department of Surgery, Thomas Jefferson University, states: "The Journal was pleased to publish this phase 1 study using a CXCR4 peptide antagonist with a PD-1 inhibitor in eight patients with advanced pancreatic cancer. The combination yielded tolerable side effects and some patients showing a certain degree of disease stability."

Credit: 
Mary Ann Liebert, Inc./Genetic Engineering News

Homeless people receive less treatment in hospitals for heart attacks, have higher readmission rates

ROCHESTER, Minn. -- Homelessness has become a social crisis and public health problem around the world, affecting people of all ages. Most homeless people are at a disadvantage with few resources, and may or may not have adequate health insurance. Mental illness and substance abuse are common issues in the homeless community. People living on the streets have a high likelihood of developing heart disease. Yet they have little ability to take care of their health.

A new study published in Mayo Clinic Proceedings examined in-hospital outcomes and 30-day readmission rates of 3,937 homeless patients from more than 1.5 million people admitted for a heart attack. Researchers used two years of data (2015-2016) from the National Readmission Database. The findings show that homeless patients often receive less treatment and are more likely to end up readmitted to the hospital within a month.

"The differences in patterns of care and clinical outcomes between homeless and nonhomeless patients are likely a reflection of the differences in risk profile at baseline," says Mohamad Alkhouli, M.D., a Mayo Clinic cardiologist and senior author of the study.

Compared to those with stable housing, homeless patients admitted with a heart attack tended to be male, about 10 years younger, and had fewer traditional risk factors for heart disease. Homeless patients in the study had a higher incidence of congestive heart failure, anemia, chronic kidney disease, and liver and lung diseases. Anxiety, depression, substance abuse and HIV infections were substantially higher for this group, as well.

Looking at matched outcomes for each group, homeless patients received less treatment in the hospital, as shown through a lower rate of angiography and revascularization. The in-hospital mortality rate and median cost of hospitalization were similar for the homeless versus patients who were not homeless.

Other differences emerged when comparing length of stay and readmission. Homeless patients were in the hospital longer. Yet they were more likely to leave against medical advice and be discharged to an intermediate care facility. They were also more likely to be readmitted. The 30-day readmission rates differed significantly, with 22.5% of homeless patients readmitted, compared to only 10% of patients who were not homeless. Cardiovascular causes were the most common reasons for readmission in both groups. However, 18% of homeless patients were readmitted for psychiatric causes, compared to 2% of patients who were not homeless.

"Addressing cardiovascular disease in the growing population of the homeless comes with a unique set of challenges," says Dr. Alkhouli. "The high burden of psychiatric illness among the homeless emphasizes the need for a holistic approach to address both the clinical and social needs of these patients."

Credit: 
Mayo Clinic

New insights into US flood vulnerability revealed from flood insurance big data

An international team of scientists, led by the University of Bristol, has found that current estimates of flood risk rely upon methods for calculating flood damage which are inadequately verified and match poorly with observations.

Instead, building damage at a given flood depth is highly variable and can be characterized by a beta distribution.

When calculating flood risk - that is, translating modelled representations of the physical of phenomenon of flooding to its impacts - it is common to apply a 'depth-damage function' or curve, which relates a given water depth to a proportional building loss (for example one metre of water equals 50 per cent loss of building value).

Academics have understood that this depth-damage relationship is variable and that there is no perfect fit, but it is still common to apply such curves which are inadequately verified.

The new study, published today in the journal Nature Communications, used commonly applied curves, developed by various US government agencies, and examined how they compare to millions of actual flood insurance claims made in the US.

The study's aim was then to find out if ubiquitous curves have any skill in replicating real measured losses and, if not, find the true relationship between depth and damage in the claims record.

It found that universally applied depth-damage curves show low skill in the replication of property-level damages, rendering the results of projects where they have been applied (for example the justification of billions of dollars of infrastructure investment) suspect.

Instead, depth-damage is highly variable: damages per depth are generally concentrated at high (>90 per cent) and low (

At low inundation depths, most damages are somewhat minimal (90 per cent) damage. But as depth increases, the distribution shifts and swings towards greater probability of high (>90 per cent) damage and lower probability of low (

Lead author, Dr Oliver Wing from Bristol's School of Geographical Sciences, said: "This relationship can be represented with a beta distribution, meaning future flood risk analyses can employ a function which properly captures the true stochastic relationship between depth and damage."

There is an implication that flood risk assessments which have relied on existing 1:1 depth-damage curves may be significant misestimates. Decisions for billions of dollars of infrastructure investment, where benefits (mitigated damages) are calculated to have exceeded costs (installing said infrastructure), are commonly green-lit even if benefits are marginally greater - yet, these benefits may have been quantified using inadequate functions.

In the development of the beta distribution-based functions, future analyses can be more robust for a plethora of applications: infrastructure investment, insurance pricing, planning decisions, and much else.

Co-author, Professor Paul Bates, also from the University of Bristol's School of Geographical Sciences, added: "We can integrate these new depth-damage functions into existing flood risk calculation architecture.

"However, the insurance claims data used to generate these do not contain information on vulnerability for non-residential buildings or enough information to incorporate secondary modifiers such as how depth-damage changes given the building is made from wood rather than concrete.

"To generate a complete suite of depth-damage information, we will need to find a way of fusing engineering knowledge with such empirical datasets so that we can compute flood risk accurately for all types of building."

Credit: 
University of Bristol

Putting artificial intelligence to work in the lab

image: Dr Agustin Schiffrin and his team at the School of Physics and Astronomy (Monash University)

Image: 
FLEET

Automated Scanning Probe Microscopy (SPM) controlled by artificial intelligence

First demonstration of fully autonomous, long-term SPM operation

An Australian-German collaboration has demonstrated fully-autonomous SPM operation, applying artificial intelligence and deep learning to remove the need for constant human supervision.

The new system, dubbed DeepSPM, bridges the gap between nanoscience, automation and artificial intelligence (AI), and firmly establishes the use of machine learning for experimental scientific research.

"Optimising SPM data acquisition can be very tedious. This optimisation process is usually performed by the human experimentalist, and is rarely reported," says FLEET Chief Investigator Dr Agustin Schiffrin (Monash University).

"Our new AI-driven system can operate and acquire optimal SPM data autonomously, for multiple straight days, and without any human supervision."

The advance brings advanced SPM methodologies such as atomically-precise nanofabrication and high-throughput data acquisition closer to a fully automated turnkey application.

The new deep learning approach can be generalised to other SPM techniques. The researchers have made the entire framework publicly available online as open source, creating an important resource for the nanoscience research community.

FULLY-AUTONOMOUS DeepSPM

"Crucial to the success of DeepSPM is the use of a self-learning agent, as the correct control inputs are not known beforehand," says Dr Cornelius Krull, project co-leader.

"Learning from experience, our agent adapts to changing experimental conditions and finds a strategy to keep the system stable," says Dr Krull, who works with Dr Schiffrin at Monash School of Physics and Astronomy.

The AI-driven system begins with an algorithmic search of the best sample regions and proceeds with autonomous data acquisition.

It then uses a convolutional neural network to assess the quality of the data. If the quality of the data is not good, DeepSPM uses a deep reinforcement learning agent to improve the condition of the probe.

DeepSPM can run for several days, acquiring and processing data continuously, while managing SPM parameters in response to varying experimental conditions, without any supervision.

The study demonstrates fully autonomous, long-term SPM operation for the first time by combining:

an algorithmic approach for sample area selection and SPM data acquisition;

supervised machine learning using convolutional neural networks for quality assessment and classification of SPM data, and

deep reinforcement learning for dynamic automated in-situ probe management and conditioning.

Credit: 
ARC Centre of Excellence in Future Low-Energy Electronics Technologies

Published consensus statement offers UTI treatment recommendations

image: Kalin Clifford, Pharm.D., from the TTUHSC Jerry H. Hodge School of Pharmacy was a member of the committee from the American Medical Directors Association - The Society for Post-Acute and Long-Term Medicine that developed a consensus statement for treating UTIs at post-acute and long-term care facilities.

Image: 
TTUHSC

They are among the most common ailments for those residing at post-acute and long-term care (PALTC) centers, yet diagnosing and managing urinary tract infections (UTIs) remains a challenging prospect for caregivers at these facilities.

In an effort to address the issue, the Infection Advisory Committee of the American Medical Directors Association - The Society for Post-Acute and Long-Term Medicine (AMDA) convened in late 2016 to devise consistent guidelines for treating UTIs. The Journal of the American Medical Directors Association published the group's consensus statement in its January issue.

According to the statement, many of the issues related to UTI treatment at PALTCs, including overdiagnosis and overtreatment, may stem from rapidly evolving advances in evidence-based UTI treatment recommendations that fail to reach busy practitioners and staff working in an environment where "fast-paced" is an understatement. This often results in the continuation of established and deeply rooted practice methods or pressure from senior staff and concerned family members to move ahead with a treatment plan that may no longer be recognized as the most effective.

As a member of AMDA's Infection Advisory Committee, Kalin Clifford, Pharm.D., an assistant professor for the Texas Tech University Health Sciences Center Jerry H. Hodge School of Pharmacy, helped develop the statement. He said the last major update to UTI treatment recommendations occurred in 2007, and though an update was issued in 2011, the discovery of new antibiotics and modifications to preferred diagnosis and treatment methods made it necessary and crucial to overhaul the guidelines.

"We realized there is a gap in the literature of what really needs to be addressed when treating urinary tract infections," Clifford said. "There's been so much change that it was time to come up with something to help today's providers, especially our nursing home colleagues, identify if a patient is truly having a UTI."

In past studies, investigators have concluded that more than 50% of antibiotics prescribed for UTI treatment in PALTC facilities may be inappropriate. In addition, Centers for Disease Control and Prevention (CDC) estimates stated that organisms that have developed resistance to multiple drugs caused more than 2 million infections in 2013 and resulted in death for more than 1% of those affected. One of the primary culprits is Clostridioides difficile (C diff), a bacterium that often appears during or shortly after treatment with antibiotics. It can cause diarrhea, an inflamed colon and, in the most severe cases, death.

PALTC residents often face an increased risk for bacterial colonization and infection from multidrug-resistant microbes like C diff than do non-PALTC residents. Proper antibiotic prescribing and use can reduce the health risks associated with these bacteria, and Clifford said the need to do so compounded the Infection Advisory Subcommittee's urgency to develop a new consensus statement to assist health care providers in diagnosing, treating and preventing UTIs.

"A lot of times urinary tract infections are diagnosed later and then overtreated, or we're treating something that's not really there," Clifford said. "This consensus statement is a reminder of what we're really looking for with urinary tract infections and what the options are to approach and treat them."

Some of the current study-related literature suggests younger adults are better able to communicate symptoms often associated with UTIs like painful urination, increased frequency or changes in urine appearance and content. Clifford said there is some observational evidence that suggests a link between UTIs and certain cognitive changes that many older adults experience, but additional research is needed to determine if such a link exists.

"We don't know what comes first; is the urinary tract infection causing confusion and the dulling of cognition or is it the confusion that is causing the UTI," Clifford explained. "That's never been addressed and never been found, it's just an association made from seeing more confusion in some older adults and then they happen to have a urinary tract infection."

In addition to the largely unstudied and unproven confusion-UTI link, Clifford said the tendency to check for a UTI has increased because testing generally requires urine analysis, a process that is not particularly difficult or expensive. If the urine analysis reveals the presence of bacteria, the inclination is to diagnose a UTI and begin antibiotic treatment without knowing for certain if the pathogen is causing a problem.

"When we overtest, there is a likelihood to also overtreat," Clifford added. "We might see there's new confusion, so let's just get a urine analysis and see if something's growing, and if there is an infection, even if we may not be sure what it is, it might cause us to go ahead and try this antibiotic anyway."

Cognition difficulties and dementia may have rendered some PALTC residents unable to communicate verbally. Others may have a history of UTI-related pathology or may be otherwise perceived as vulnerable or immune compromised. In some circumstances, Clifford said, residents presenting these conditions may prompt a clinician to test for a UTI and then prescribe antibiotic treatment without having a complete picture of the infection. However, he cautions, simply identifying bacteria in urine in a person experiencing one or more of these factors doesn't always mean an antibiotic is required.

In creating its consensus statement, Clifford said the committee's primary objective was to encourage clinicians to go beyond reflexively ordering a urine analysis and antibiotics. Rather than focusing solely on symptoms like confusion and urine samples, the committee advises looking for additional factors. For instance, is the person using the restroom more often? If they have been diagnosed with dementia, is the dementia getting worse? Do you have to change their undergarments more often?

"Let's try to make sure the indication for starting antibiotics is truly there and that they're truly needed," Clifford emphasized. "First, let's look for a couple other symptoms before going straight to that. That's what we're going for with this document. We're trying to effectively explain what's been found over the last few years. The goal is to try to protect the antibiotics that we have and try to use everything appropriately."

Now that the statement has been published, Clifford said the committee is in the process of getting the recommendations into the hands health care providers, especially those in PALTC settings. As is the case with most other medical literature, it takes time to get the information disseminated. To aid the process, AMDA is developing a mini-brochure that practitioners can carry in their lab coat pocket or work bag so they can more quickly and easily reference the statement's main recommendations.

"This can't just be a one-off thing; you really do have to look for other changes, you do have to look for other symptoms. That's really what we're going on with this statement," Clifford stressed. "It's not thinking, 'Hey, they're confused and they weren't yesterday; so check for a UTI.' It's about trying to encourage everybody to take a minute and think about it before throwing on an antibiotic. It's really about stressing the need to know your patient as much as you can."

Credit: 
Texas Tech University Health Sciences Center

New brain disorder discovery

image: A study has uncovered a new neurodegenerative disorder in which children experience developmental regression and severe epilepsy.

Image: 
Robina Weermeijer

A study has uncovered a new neurodegenerative disorder in which children experience developmental regression and severe epilepsy.

The study, led by the Murdoch Children's Research Institute (MCRI) and published in The American Journal of Human Genetics, found a variation in a gene causes a severe childhood-onset neurodegenerative disorder that has never before been described.

MCRI and Victorian Clinical Genetics Services (VCGS) Associate Professor Sue White said this newly discovered condition was different from other chronic neuroinflammation implicated in other neurodegenerative conditions such as Alzheimer's disease, Parkinson's disease and frontotemporal dementia.

Associate Professor White said the study participants started with normal or mild developmental delay, and the onset of seizures started within the first year of life.
All had a severe and progressive developmental regression following a seizure, she said.

The study looked at six children from four families with the gene variant who had a similar degenerative condition, the cause of which was unlocked by genomic testing.

The genomic testing and data analyses were conducted for four participants at VCGS in Melbourne and one each at Ospedale Pediatrico Bambino Gesù in Italy and at Baylor College of Medicine in the US.

Associate Professor White said the disorder, with features suggestive of neuroinflammation, appeared to require two copies of the defective gene, meaning both parents had to be carriers of one altered copy.

"In our study the same gene variant was identified in three children of the same ethnic background," she said.

"While the families do not report that their two families are directly related, they are presumed to be distantly related due to the overlap of their family histories, with common ancestors originating from the same town."

The researchers used advanced molecular techniques to dissect the likely cellular pathway affected by the mutation in the NRROS gene. By inserting the gene into cells in the laboratory, they identified other molecules that NRROS interacts with. These molecules are crucial for a number of brain cell functions, including adding the insulating layers around nerve fibres, and producing brain immune cells.

"In line with these laboratory findings, our study participants had neurodegenerative symptoms with difficult to control epilepsy, developmental regression, and delayed myelination," Associate Professor White said.

"The myelination process is vitally important to healthy central nervous system functioning, enabling nerve cells to transmit information faster and allows for more complex brain processes."

MCRI Professor John Christodoulou said the outcomes of this research highlighted the power of new genomic sequencing technologies that had ended a diagnostic odyssey that for some families may take years.

"Now that we know the causative gene, we are in a better position to understand the underlying biology behind the disorder, which we hope in future may translate to targeted treatments specific for the disorder," he said.

Researchers from the University of Melbourne, The Royal Children's Hospital, Università degli Studi di Palermo in Italy, Texas Children's Hospital and Austin Health also contributed to the findings.

Credit: 
Murdoch Childrens Research Institute

A giant right atrial myxoma with blood supply from the left and right coronary arteries

A Giant Right Atrial Myxoma with Blood Supply from the Left and Right Coronary Arteries: Once in a Blue Moon

In a new publication from Cardiovascular Innovations and Applications; DOI https://doi.org/10.15212/CVIA.2019.0566, Yichao Xiao, Zhenfei Fang, Xinqun Hu, Qiming Liu, Zhaowei Zhu, Na Liu, Xiaofan Peng and Shenghua Zhou from the Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China consider Cardiac myxomas.

In this case report the authors discuss cardiac myxomas, which are the commonest primary benign cardiac tumors, they are extremely rare, with an incidence ranging from 0.0017 to 0.19% and only about one-fifth of them originate from the right chambers of the heart. A 60-year-old woman was admitted because of recurrent attacks of chest tightness and shortness of breath. Transthoracic echocardiography detected a giant mass in the right atrium; myxoma was indicated by [18F]fluorodeoxyglucose PET/CT. Preoperative selective coronary angiography was performed to assess the extent and severity of coronary stenosis, and showed a strongly neovascularized right atrial mass supplied by two feeding vessels with multiple branches from the left and right coronary arteries. The myxoma was successfully excised with open heart surgery and the patient was free of myxoma recurrence during the 3-year follow-up.

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Credit: 
Cardiovascular Innovations and Applications