Culture

Pesticides safeguard agricultural yields by controlling harmful insects, fungi, and weeds. However, they also enter neighbouring streams and damage the aquatic communities, which are crucial for maintaining biodiversity, are part of the food web and support the self-purification of water. In a nationwide monitoring programme, a consortium of scientists led by the Helmholtz Centre for Environmental Research (UFZ) has shown that the governmental thresholds for pesticides are generally too high and that even these excessively high levels are still exceeded in over 80% of water bodies. As they published in the scientific journal Water Research the loss of biodiversity can only be halted if the environmental risk assessment of pesticides is radically revised.

For two years, the researchers studied pesticide contamination at more than 100 monitoring sites on streams flowing through predominantly agricultural lowland regions in 12 federal states in Germany. They found significant exceedances of the RAC value - the concentration of an active ingredient specified in the official approval procedure for a pesticide, which should not be exceeded in the water body in order to prevent negative effects on aquatic organisms. In most of the small streams investigated, the RAC values were exceeded (81%). In 18% of the streams, such exceedances were detected for more than 10 pesticides. "We have detected a significantly higher pesticide load in small water bodies than we originally expected", says Prof. Matthias Liess, ecotoxicologist at the UFZ and coordinator of the small water monitoring project. For example, in three water bodies, the insecticide thiacloprid exceeded the RAC value by more than 100-fold. In 27 streams the insecticides clothianidin, methiocarb, and fipronil as well as herbicides such as terbuthylazine, nicosulfuron, and lenacil exceeded the RAC value 10- to 100-fold.

Because of the extensive data set, the researchers were able to reveal that pesticides affect aquatic invertebrate communities at much lower concentrations than previously assumed by the pesticide risk assessment. The concentrations depend on which species are to be conserved. For example, sensitive insect species such as caddisflies and dragonflies require much lower (1.000-fold) threshold values than snails and worms. "For sensitive insect species, the pesticide concentration in the small lowland streams is the most relevant factor that determines their survival. In contrast, other environmental problems such as watercourse expansion, oxygen deficiency, and excessive nutrient content are less important. For the first time this study allows a ranking of environmental problems", says Liess.

For the current approval of pesticides, the high sensitivity of species in the ecosystem context is grossly underestimated. Until now, the ecological risk of pesticides in the field has been predicted based on laboratory studies, artificial ecosystems, and simulation models. However, according to Liess, the results from the laboratory do not reflect reality. "In addition to pesticides, many other stressors act on organisms in the ecosystem. These make them much more sensitive to pesticides. Natural stressors such as predation pressure or competition between species are not sufficiently taken into account in the risk assessment. But these obvious problems often go unnoticed because the degree of pesticide contamination and the effect of this have not been validated in the field - neither in Germany nor in other countries", he says.

In the course of the project, the scientists also found that the type of sampling has a drastic influence on the concentrations of pesticides measured. In addition to the scoop sample specified as standard by the EU Water Framework Directive, they also took an "event sample". Here, an automatically controlled sampler takes water samples from the water body after a rain event. "The event sample provides much more realistic results because the pesticides enter the water bodies as a result of the increased surface run-off from the field, especially during rain", says Liess. Compared to the scoop samples, the event-related samples show a 10-fold higher pesticide load. "In order to realistically depict the water pollution, samples must therefore be taken after rainfall events. That's why we need an official regular environmental monitoring to be able to assess the amount and the effects of pesticides," says Matthias Liess. He and his colleagues also demand that new scientific findings be incorporated into the approval process for new pesticides more quickly. "We are still using pesticides that were approved many years ago based on an outdated risk assessment. This must therefore change as soon as possible. Only in this way can we preserve the biodiversity in our waters and with it the services that these biotic communities provide for our ecosystems."

DUBLIN, June 15, 2021 - Scientists have identified how and why some Covid-19 patients can develop life-threatening clots, which could lead to targeted therapies that prevent this from happening.

The work, led by researchers from RCSI University of Medicine and Health Sciences, is published in the Journal of Thrombosis and Haemostasis.

Previous research has established that blood clotting is a significant cause of death in patients with Covid-19. To understand why that clotting happens, the researchers analysed blood samples that were taken from patients with Covid-19 in the Beaumont Hospital Intensive Care Unit in Dublin.

They found that the balance between a molecule that causes clotting, called von Willebrand Factor (VWF), and its regulator, called ADAMTS13, is severely disrupted in patients with severe Covid-19.

When compared to control groups, the blood of Covid-19 patients had higher levels of the pro-clotting VWF molecules and lower levels of the anti-clotting ADAMTS13. Furthermore, the researchers identified other changes in proteins that caused the reduction of ADAMTS13.

"Our research helps provide insights into the mechanisms that cause severe blood clots in patients with Covid-19, which is critical to developing more effective treatments," said Dr Jamie O'Sullivan, the study's corresponding author and research lecturer within the Irish Centre for Vascular Biology at RCSI.

"While more research is needed to determine whether targets aimed at correcting the levels of ADAMTS13 and VWF may be a successful therapeutic intervention, it is important that we continue to develop therapies for patients with Covid-19. Covid-19 vaccines will continue to be unavailable to many people throughout the world, and it is important that we provide effective treatments to them and to those with breakthrough infections."

The University of Ottawa has been awarded four new Canada Research Chairs (CRC) that will strengthen its expertise in artificial intelligence, health and law. The University is also proud to announce the renewal of two CRCs that will conduct leading-edge research in quantum communications and photonics.

"The Canada Research Chairs Program provides invaluable support to our researchers as they forge their paths of discovery at a world-class level," said Sylvain Charbonneau, vice-president, research. "The results of this most recent competition will undeniably help the University succeed in pursuing our goals of excellence, relevance and research impact."

The three new Tier 1 Canada Research Chairs are:

Khaled El Emam (Faculty of Medicine and CHEO Research Institute) -- Canada Research Chair in Medical Artificial Intelligence

Khaled El Emam's research will focus on developing a methodology for the synthesis of complex health data. This means applying artificial intelligence techniques to model personal clinical and biological information stored in databases. These models can be used to generate virtual patients that mimic the characteristics of real patients. This solves data-sharing problems and enables adding simulated patients to accelerate clinical studies.

Rita Horvath (Faculty of Medicine and CHEO Research Institute) -- Canada Research Chair in Mitochondrial Disease Pathogenesis to Therapy

Mitochondrial diseases are genetic disorders that are difficult to diagnose and cause a range of devastating physical, developmental and intellectual disabilities. Rita Horvath's research aims to understand the molecular mechanisms of mitochondrial disease, to provide accurate diagnosis and develop targeted therapies.

Carole Yauk (Faculty of Science) -- Canada Research Chair in Genomics and the Environment

Carole Yauk's research addresses an urgent need to modernize the toxicological risk assessment of environmental chemicals. She will develop and deploy genomics approaches that measure how toxic chemicals can alter the function of genes or damage genetic material. Her laboratory will work with regulatory and industry partners to determine the best use of this information, to predict toxicological risks to humans and wildlife.

The new Tier 2 Canada Research Chair is:

Emmanuelle Bernheim (Faculty of Law, Common Law Section) -- Canada Research Chair in Mental Health and Access to Justice

Emmanuelle Bernheim's research looks at improving access to the justice system for diverse groups, particularly those living with mental health issues, while focussing on community, political and research circles.

The two renewed Tier 2 Canada Research Chairs are:

Ksenia Dolgaleva (Faculty of Engineering) -- Canada Research Chair in Integrated Photonics

Photonic integration uses light for applications traditionally performed by electronics. Combining a laser source, waveguides that direct light and other optical components on a small semiconductor chip, photonics has a number of uses in areas such as medicine, information and communication technologies, and sensing. Ksenia Dolgaleva's research aims to increase the functionality of existing optical chips by developing integrated optical devices that can manipulate light in new ways. These devices will be able to change the colour of incident light and manipulate light with light. This is essential to all-optical processing of information channels without needing to convert them to an electrical current.

Ebrahim Karimi (Faculty of Science) -- Canada Research Chair in Structured Quantum Waves

Ebrahim Karimi's research program uses structured quantum waves to enhance capabilities and open new horizons in quantum communication protocols, simulators and sensing. Robust yet compact devices will be designed to efficiently structure electron and optical beams, increasing the security and capacity of information transmission -- the key to establishing the first quantum network across Ottawa -- as well as measuring and analyzing materials properties quickly on a small scale.

A review of more than 9,000 U.S. patients with severe COVID-19 infection showed less than 1% contracted the illness again, with an average reinfection time of 3.5 months after an initial positive test. Those are the findings from a study conducted by researchers from the University of Missouri School of Medicine and MU Health Care.

The researchers teamed up with the MU Institute for Data Science and Informatics and the Tiger Institute for Health Innovation to review data from 62 U.S. health care facilities. They found 63 of the 9,119 patients (0.7%) with severe COVID-19 infection contracted the virus a second time, with a mean reinfection period of 116 days. Of the 63 who were reinfected, two (3.2%) died. Patients categorized as non-white were at greater risk of reinfection than white patients.

"Our analysis also found asthma and nicotine dependence were associated with reinfection," said lead researcher Adnan I. Qureshi, MD, a professor of clinical neurology at the MU School of Medicine. "However, there was a significantly lower rate of pneumonia, heart failure and acute kidney injury observed with reinfection compared with primary infection."

Qureshi defined reinfection by two positive tests separated by an interval greater than 90 days after the initial infection resolved, as confirmed by two or more consecutive negative tests. He analyzed data from patients who received serial tests between December 2019 and November 2020.

"This is one of the largest studies of its kind in the U.S., and the important message here is that COVID-19 reinfection after an initial case is possible, and the duration of immunity that an initial infection provides is not completely clear," Qureshi said.

In addition to Qureshi, the study authors include fellow MU School of Medicine collaborators Iryna Lobanova, MD, research specialist in the Department of Neurology; S. Hasan Naqvi, MD, associate professor of clinical medicine; William Baskett, graduate student; Wei Huang, graduate student; and Chi-Ren Shyu, PhD, Director, MU Institute for Data Science and professor of Informatics, Electrical Engineering and Computer Science.

June 15, 2021 - Canadian researchers have discovered that a bee thought to be one of the rarest in the world, as the only representative of its genus, is no more than an unusual specimen of a widespread species.

Scientists with the Canadian Museum of Nature (CMN) and York University have reclassified the mystery bee, collected somewhere in Nevada in the 1870s, as Brachymelecta californica. They note that it's an aberrant individual of a species, the California digger-cuckoo bee, that is part of a group that includes five other species. All are cleptoparasitic bees, with females that lay eggs in the nests of digger bees. Brachymelecta californica itself is known to be widespread from western Canada to southern Mexico.

The paper setting the record straight is published today in the European Journal of Taxonomy. "The unusual specimen has puzzled bee researchers for decades, and deceived some of the world's great experts on bee taxonomy" says Dr. Thomas Onuferko, research associate with the CMN and the study's lead author. "They can now stop searching for more examples of this 'rare' bee."

The bee was first described in 1879 by American entomologist Ezra Townsend Cresson from the Nevada specimen. It was later placed in its own genus, and renamed Brachymelecta mucida in 1939, a name that has only ever been associated with this lone specimen.

It stood apart from other related bees because its abdomen's dorsal surface is unusually covered in pale hairs, these being partly dark in other specimens of what are now understood to be the same species. Another unusual feature is that the fore wings of the specimen each have two submarginal cells (the normal number for the bees in this group is three). These two features had confused everyone, until now.

In 2019, Onuferko was able to examine the rare specimen during a visit to the collections at Philadelphia's Academy of Natural Sciences of Drexel University. There, he discovered a series of other specimens with the same vague locality labels, but these bees were identified as Xeromelecta californica, a species that was also described by Cresson in the year before the description of the mystery species.

In some of the specimens, the pattern of veins in the wings is the same as in the mystery specimen. "At that point, I made the connection that these specimens might all be the same species," says Onuferko.

This connection was further boosted by the discovery in Dr. Laurence Packer's collection at York University of a bee that also had conspicuously pale hairs on its entire abdomen. DNA barcoding confirmed the specimen to be Xeromelecta californica. Hairs that are normally dark in this species were completely light. Onuferko and Packer, who also collaborated on the study, concluded that the hairs likely lacked pigmentation due to a form of partial albinism.

The finding surprised Packer because some of the best bee biologists had studied the specimen, but he adds, "Rummaging around in old collections is actually an important thing to do. There is a lot to discover within museum collections, and in this case the rummaging revealed that a rare bee is not so rare after all."

The discovery has prompted an unusual name change, which is based on rules of the organization that governs the naming of animal species--the International Commission of Zoological Nomenclature. Due to the chronology of dates in which the bees' various genus and species names were published, Brachymelecta californica takes precedence as the accepted name, and the five related species classified as Xeromelecta are now also part of the genus Brachymelecta. This genus, previously known from a single specimen, is now known from most of the bee collections in North America.

"The reclassification of this bee shows why it's important to describe new taxa from multiple examples and why entomologists collect specimens in series," explains Onuferko. It is impossible to know the range of variation within a species with a single specimen, and describing new species from a lone sample risks mistaking an aberrant specimen for a new species.

New species still occasionally get described from single specimens; however, in such cases the new species should be thoroughly justified (using both molecular and morphological evidence, if possible), to avoid taxonomic problems down the line.

The study's authors explain that many researchers have written about the mystery bee under its earlier classification as Brachymelecta mucida, meaning that intellectual resources were dedicated to a specimen that did not merit them. "Bee collectors were effectively in search of an elusive 'white whale; or more appropriately, a 'whitish bee', a species that evidently only existed in the minds of taxonomists," says Onuferko.

A recent UCLA clinical trial has shown encouraging results in helping daily smokers who are also heavy drinkers quit smoking and cut down their alcohol intake.

The study of 165 people tested two prescription drugs -- varenicline, for smoking addiction, and naltrexone, which is used to treat alcoholism. Studies have shown that varenicline, marketed under the brand name Chantix, may also be effective in reducing alcohol consumption.

Participants, who ranged in age from 21 to 65, smoked at least five cigarettes a day, with male participants generally consuming more than 14 drinks a week and women more than seven per week.

Over the 12-week study period, each participant received 2 milligrams of varenicline twice a day. Roughly half the group -- 83 participants -- also received a 50-milligram dose of naltrexone daily, while the other 82 received placebo pills. They were all told to quit smoking and drink less.

When researchers followed up 26 weeks after the study's conclusion, they found that nearly 36% -- 59 participants -- had quit smoking.

"The overall smoking quit rate in the trial is impressive," said lead author Lara Ray, a professor of psychology and of psychiatry and biobehavioral sciences who holds UCLA's Shirley M. Hatos Chair in Clinical Neuropharmacology. She noted that previous studies have suggested varenicline has a success rate at six months of about 25% to 30%.

"We exceeded the overall expectation for this medication," she said. "This is especially important in a diverse group of people." Ray said that while some previous studies have shown lower-than-average smoking cessation rates among Black participants, that was not the case in the current trial, in which more than half of participants were Black.

Surprisingly, the researchers said, those who had received varenicline plus a placebo had a significantly higher smoking quit rate (45%, or 37 of 82 participants) than those who were given varenicline and naltrexone (27%, or 22 of 83 participants).

"The quit rate for varenicline alone in this sample is highly encouraging, as this is the first large-scale trial of varenicline efficacy focused solely on heavy-drinking smokers," Ray said.

While participants who received varenicline plus naltrexone had a lower smoking quit rate, they had slightly better success than the placebo group at curbing their drinking. At the start of the study, participants averaged nearly seven drinks per drinking day; those on the varenicline-naltrexone combination reduced their consumption to three drinks per drinking day over the 12-week study period, while those receiving the varenicline-placebo combination cut down to four drinks -- both impressive decreases, Ray said.

"I am excited about both the smoking cessation rates and the drinking reductions," said Ray, who is also a member of UCLA's Brain Research Institute. "These findings suggests that desirable outcomes for smoking cessation and drinking reduction are achievable."

The study, which found no difference in quit and reduction rates between men and women, was published online in the American Journal of Psychiatry June 3 and is scheduled for publication in the journal's September print issue.

Approximately 20% to 25% of smokers are also heavy drinkers. Smoking and heavy drinking are major public health concerns that reduce people's life span and quality of life, and both have also been linked to worse health outcomes for COVID-19.

As with all addictions, quitting smoking and reducing drinking are difficult and complex processes. This study confirms that medications can play a role, Ray said, but she noted that it can be challenging for patients to take more than one prescribed medication.

"Varenicline alone is doing a great job, and this trial indicates that there is not much room for naltrexone to make a difference," Ray said. "But even medications like varenicline have their limitations. Medication is only part of the solution. There remains much research to be done on addictions and how to treat them."

Ray says that those who wish to quit smoking and reduce drinking may consider talking to their doctor about the possibility of using varenicline, and she recommends that they try to quit smoking and reduce their drinking at the same time.

"There is evidence that varenicline can help them with both," Ray said. "Varenicline appears quite effective at reducing drinking and helping people to quit smoking. Given that varenicline has been found to reduce drinking in trials for alcohol use disorder, it is possible that its effects on both drinking and smoking present an optimal alternative for this group of heavy-drinking smokers."

ReJoyce Green, a UCLA doctoral student in clinical psychology who works with Ray, and Karen Miotto, a UCLA clinical professor of psychiatry and the medical director of the clinical trial, are among the study's 14 authors.

The clinical trial and Ray's research are funded by the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism, both part of the National Institutes of Health.

The study was conducted between July 2015 and December 2019 at an outpatient research facility at UCLA.

A new model that applies artificial intelligence to carbohydrates improves the understanding of the infection process and could help predict which viruses are likely to spread from animals to humans. This is reported in a recent study led by researchers at the University of Gothenburg.

Carbohydrates participate in nearly all biological processes - yet they are still not well understood. Referred to as glycans, these carbohydrates are crucial to making our body work the way it is supposed to. However, with a frightening frequency, they are also involved when our body does not work as intended. Nearly all viruses use glycans as their first contact with our cells in the process of infection, including our current menace SARS-CoV-2, causing the COVID-19 pandemic.

A research group led by Daniel Bojar, assistant professor at the University of Gothenburg, has now developed an artificial intelligence-based model to analyze glycans with an unprecedented level of accuracy. The model improves the understanding of the infection process by making it possible to predict new virus-glycan interactions, for example between glycans and influenza viruses or rotaviruses: a common cause for viral infections in infants.

As a result, the model can also lead to a better understanding of zoonotic diseases, where viruses spread from animals to humans.

"With the emergence of SARS-CoV-2, we have seen the potentially devastating consequences of viruses jumping from animals to humans. Our model can now be used to predict which viruses are particularly close to "jumping over". We can analyze this by seeing how many mutations would be necessary for the viruses to recognize human glycans, which increases the risk of human infection. Also, the model helps us predict which parts of the human body are likely targeted by a potentially zoonotic virus, such as the respiratory system or the gastrointestinal tract", says Daniel Bojar, who is the main author of the study.

In addition, the research group hopes to leverage the improved understanding of the infection process to prevent viral infection. The aim is to use the model to develop glycan-based antivirals, medicines that suppress the ability of viruses to replicate.

"Predicting virus-glycan interactions means we can now search for glycans that bind viruses better than our own glycans do, and use these "decoy" glycans as antivirals to prevent viral infection. However, further advances in glycan manufacturing are necessary, as potential antiviral glycans might include diverse sequences that are currently difficult to produce", Daniel Bojar says.

He hopes the model will constitute a step towards including glycans in approaches to prevent and combat future pandemics, as they are currently neglected in favor of molecules that are simpler to analyze, such as DNA.

"The work of many groups in recent years has really revolutionized glycobiology and I think we are finally at the cusp of using these complex biomolecules for medical purposes. Exciting times are ahead," says Daniel Bojar.

Researchers at the University of Maryland School of Medicine (UMSOM) have developed two rapid diagnostic tests for COVID-19 that are nearly as accurate as the gold-standard test currently used in laboratories. Unlike the gold standard test, which extracts RNA and uses it to amplify the DNA of the virus, these new tests can detect the presence of the virus in as little as five minutes using different methods.

One test is a COVID-19 molecular diagnostic test, called Antisense, that uses electrochemical sensing to detect the presence of the virus. The other uses a simple assay of gold nanoparticles to detect a color change when the virus is present. Both tests were developed by Dipanjan Pan, PhD, Professor of Diagnostic Radiology and Nuclear Medicine and Pediatrics at UMSOM and his research team. Dr. Pan has a joint appointment at the University of Maryland Baltimore County (UMBC).

"These tests detect the presence of the virus within 5 to 10 minutes and rely on simple processes that can be performed with little lab training," said Dr. Pan. They do not require the extraction of the virus's RNA - which is both complicated and time consuming.

They also are more reliable than the rapid antigen tests currently on the market, which detect the virus only in those with significantly high viral levels. "These two newer tests are extremely sensitive and can detect the presence of the virus, even in those with low levels of the virus," Dr. Pan said.

Dr. Pan's team included UMSOM research fellow Maha Alafeef, UMSOM research associate Parikshit Moitra, PhD, and research fellow Ketan Dighe, from UMBC.

Last month, the U.S. Food and Drug Administration (FDA) registered the laboratory of Dr. Pan as an approved laboratory development site for the Antisense test. The move paves the way for Dr. Pan's laboratory to begin conducting the test at the university, in research settings, as it undergoes further development.

In February, RNA Disease Diagnostics, Inc. (RNADD) received an exclusive global license from UMB and UMBC to commercialize the test. Dr. Pan serves as an unpaid scientific advisor to the company.

This test detects the virus in a swab sample using an innovative technology called electrochemical sensing. It uses a unique dual-pronged molecular detection approach that integrates electrochemical sensing to rapidly detect the SARS-CoV-2 virus.

"The final prototype is like a glucometer, which patients with diabetes use at home to measure their blood glucose levels," said Dr. Pan, "and is just as easy for people to do themselves."

Dr. Pan and his colleagues, in collaboration with RNA Disease Diagnostics, are launching a study of NBA basketball players in New York City to compare the Antisense test to rapid COVID tests that the NBA is using to monitor COVID infections in its players.

"We would like to see whether our test can yield more reliable results compared to the existing platforms," he said. "Current antigen-based rapid COVID tests miss infections about 20 percent of the time and also have high rates of false positive results. Our Antisense test appears to be about 98 percent reliable, which is similar to the PCR test."

Similar to the Antisense test, the second rapid test also does not require the use of any advanced laboratory techniques, such as those commonly used to extract RNA, for analysis. It uses a simple assay containing plasmonic gold nanoparticles to detect a color change when the virus is present. In April, Dr. Pan and his colleagues published a stepwise protocol in the journal Nature Protocols, explaining how the nano-amplified colorimetric test works and how it can be used.

Once a nasal swab or saliva sample is obtained from a patient, the nucleic acid (bits of genetic material) in the sample is amplified via a simple process that takes about 10 minutes. The test uses a highly specific molecule attached to the gold nanoparticles to detect a particular protein. This protein is part of the genetic sequence that is unique to the novel coronavirus. When the biosensor binds to the virus's gene sequence, the gold nanoparticles respond by turning the liquid reagent from purple to blue.

"Innovations in COVID-19 testing remain incredibly important even as the epidemic appears to be waning in this country," said E. Albert Reece, MD, PhD, MBA, Executive Vice President for Medical Affairs, UM Baltimore, and the John Z. and Akiko K. Bowers Distinguished Professor and Dean, University of Maryland School of Medicine. "As we continue to monitor infections in unvaccinated segments of our population and the potential spread of new variants, there will be a vital need for inexpensive rapid tests to ensure that we continue to maintain low infection rates."

WASHINGTON -- Researchers have fabricated a magnetically driven rotary microfilter that can be used to filter particles inside a microfluidic device. They made the tiny turning filter by creating a magnetic material that could be used with a very precise 3D printing technique known as two-photon polymerization.

Microfluidic devices, also known as lab-on-a-chip devices, can be used to perform multiple laboratory functions inside a chip that usually measures a few square centimeters or less. These devices contain intricate networks of microfluidic channels and are becoming more and more complex. They may be useful for a variety of applications such as screening molecules for therapeutic potential or performing blood tests that detect disease.

"By changing the direction of external magnetic field, the microfilter we made can be remotely manipulated on demand to either filter certain-sized particles or to allow them all to pass," said Dong Wu, a member of the research team from the University of Science and Technology of China. "This functionality could be used for many types of chemical and biological studies performed in lab-on-a-chip devices and, importantly, makes it possible for the chips to be reused."

In The Optical Society (OSA) journal Optics Letters, Wu together with colleagues from the Hefei University of Technology and RIKEN Center for Advanced Photonics in Japan show that their new rotary microfilter filters can sort particles in a microfluidic device with high performance.

"This filter could eventually be used to sort cells of different sizes for applications such as isolating circulating tumor cells for analysis or detecting abnormally large cells that may indicate disease," said Chaowei Wang from University of Science and Technology of China. "With further development it might even be possible to use it in devices placed inside the body for cancer detection."

A more versatile filter

Filters with micrometer-sized holes are often used in microfluidic chips as a passive way to sort particles or cells based on sizes of the holes. However, because the number and shape of holes in the filter cannot be dynamically changed, available devices lack the flexibility to sort different types of particles or cells on demand. To expand the usefulness of microfluidic devices, the researchers developed a filter that can freely switch between modes such as selective filtering and passing.

They created the new filter using two-photon polymerization, which uses a focused femtosecond laser beam to solidify, or polymerize, a liquid light-sensitive material known as photoresist. Thanks to two-photon absorption, the polymerization can be done in a very precise manner, enabling fabrication of complex structures on the micron scale.

To make the microfilter, the researchers synthesized magnetic nanoparticles and mixed them with the photoresist. Fabricating the rotary microfilter required them to optimize the laser power density, number of pulses and scanning intervals used for polymerization. After testing its magnetically driven properties on a glass slide, they integrated the microfilter into a microfluidic device.

Multiple filtering modes

To filter larger particles, a magnetic field perpendicular to the microchannel is applied. After the filtering process is complete, the large particles can be released by applying a magnetic field that is parallel to the microchannel, which will rotate the microfilter by 90°. The filtering process can then be repeated as needed.

The researchers verified the filtering performance of the filter using polystyrene particles with diameters of 8.0 and 2.5 microns that were mixed in an alcohol solution. "It was clear that particles smaller than the pore size easily passed through microfilter while bigger ones were filtered out," said Chenchu Zhang from University of Science and Technology of China. "When in passing mode, any larger particles captured by the filter were washed away with the fluid, which prevents filter clogging and allows reuse of the microfilter."

2 June 2021, Singapore - The human fetal immune system begins to develop early during gestation, however, factors responsible for fetal immune-priming remain elusive. Using multiple complementary approaches, Dr Florent Ginhoux from A*STAR's Singapore Immunology Network (SIgN), Professor Jerry Chan from KK Women's and Children's Hospital (KKH), Professor Salvatore Albani from the SingHealth Duke-NUS Translational Immunology Institute, with collaborators from Cambridge University explored potential exposure to microbial agents in-utero. The team identified live microbes across fetal organs that stimulate activation of fetal T-cells during the second trimester of gestation. Study published in scientific journal, Cell, on 24 June 2021.

The team profiled microbes across fetal organs using 16S-rRNA gene sequencing and detected low but consistent microbial signal in fetal gut, skin, placenta and lungs, in the second trimester of gestation. They identified several live bacterial strains including Staphylococcus and Lactobacillus in fetal tissues, which induced in vitro activation of memory T-cells in fetal mesenteric lymph-node, supporting the role of microbial exposure in fetal immune-priming. Finally, using scanning electron microscope (SEM) and Ribonucleic acid (RNA) in situ hybridisation (RNA-ISH), discrete localisation of bacteria-like structures and eubacterial-RNA were visualised within the 14th week fetal gut lumen. These findings indicate selective presence of live microbes in fetal organs during second trimester of gestation and have broader implications on the establishment of immune competency and priming before birth.

The findings demonstrate that healthy human fetal tissues (in the second trimester of gestation) contain effector memory T-cells, a sparse biomass of bacteria and an active memory T-cell response towards fetal bacteria. It also demonstrates direct spatial localisation of bacterial entities, localised within the lumen of developing fetal gut, during second trimester of gestation.

Dr Florent Ginhoux, Senior Principal Investigator, SIgN and co-last author of the study said, "Our study demonstrates that such microbial presence primes the fetal immune system, thereby putting early microbial memory in the context of fetal immune priming, a concept not explored before in fetal immunity. It will be interesting to explore the precise nature of these microbial antigen-specific circulatory and immune cells that reside in human fetal organ tissues, and their potential role in imparting selective defence against pathogenic microbes in neonatal and adult life. Taken together, these findings have wider implications in understanding the key factors involved in fetal immune system development and priming in utero, which may set the basis for life-long human health and immunity of the organism."

Persisting symptoms thought to be complex interplay between effects of new injury and underlying conditions

Strict rest after a sports related concussion slows recovery and may prolong symptoms, says a consensus statement drawn up by a US expert panel on how best to treat and manage the condition, and published in the British Journal of Sports Medicine.

Most of these concussions get better within a month and can be effectively treated, it says.

Persisting symptoms are thought to be a complex interplay between the physical and psychological effects of the new injury and underlying conditions.

The consensus statement was developed by the Team Physician Consensus Conference (TPCC), an annual project-based alliance of six major professional associations,* with the aim of helping team doctors to provide the best medical care for athletes.

It updates a previous version on the management of concussion, published in 2011.

Data harvested from US emergency department visits, doctors' appointments, and a high school injury surveillance system (RIO) estimate the number of sports related concussions to be between 1 and 1.8 million every year in the USA alone among those up to the age of 18, with around 400,000 occurring in high school athletes.

But the symptoms of concussion aren't specific and there are currently no clinically useful diagnostic tests, such as blood tests, genetic tests or standard imaging techniques. So the true incidence and prevalence of sports related concussion remain unknown, says the statement.

Signs and symptoms indicating more severe brain or neck (cervical spine) injury and warranting immediate emergency care include:

Immediate seizure (at or minutes after impact)

More than brief loss of consciousness

Severe or worsening headache

Persistent or recurrent vomiting

Increasing lethargy, confusion

Tingling or numbness in hands and/or feet; double vision

Neck pain; bony tenderness; limited range of movement and/or deformity

And there is a range of symptoms that may occur immediately or some time later, which may also be indicative of concussion, says the statement.

These include: amnesia; disorientation; brain fog; inability to focus; slurred speech; excessive drowsiness; headache; dizziness; balance issues; visual disturbances; hypersensitivity to noise; irritability; and sleep disturbances.

Most sports related concussion is treatable, says the statement. And most affected athletes will recover fully within 2 (adults) to 4 weeks (children).

The number and severity of the initial array of symptoms best predict how long it will take to recover.

Factors that may prolong or complicate recovery include: previous concussions; loss of consciousness for more than 1 minute; younger age; pre-existing conditions, including migraine, ADHD, learning disabilities, depression, anxiety/panic attacks, and motion sickness.

Current evidence suggests that strict rest after a concussion slows recovery and increases the probability of prolonged symptoms. Recent research shows that progressive moderate aerobic exercise within the first week helps aid recovery.

Most athletes don't require over-the-counter and/or prescription meds for acute symptoms. And there's no current evidence to suggest that 'nutraceuticals' help to either ward off or treat concussion, says the statement.

Persisting symptoms, such as fatigue, headache, and anxiety, aren't usually caused by one factor alone, but are thought to be a complex interplay between the physical and psychological effects of the new injury and underlying conditions, says the statement.

In these circumstances, treatment should focus on the particular symptom: cognitive behavioural therapy and/or lifestyle changes to sleep, nutrition, and hydration, for example.

More high quality research is needed to fully understand young people's risks of taking part in sport after concussion and the effects on their long term brain health and wellbeing, says the statement.

"Most athletes who have been concussed will get better, and will be able to return to play," comments Dr Margot Putukian, TPCC executive committee member.*

"Each injury is unique and will have its own timeline. But athletes should take comfort in knowing that there are treatments out there, and there are steps they can take to aid their own recovery, she adds.

The number of people dying from cardiovascular disease (CVD) in Asia is increasing rapidly, with over half of all CVD deaths globally in 2019 occurring in Asian countries, according to a state-of-the-art review paper published in the inaugural issue of JACC: Asia. The data demonstrates an urgent need to understand the burdens and epidemiological features of CVD in Asian countries to develop localized CVD prevention strategies to combat the epidemic.

From 1990 to 2019, the number of CVD deaths in Asia rose from 5.6 million to 10.8 million. Nearly 39% of these CVD deaths were premature, meaning they occurred in a person less than 70 years old, which was significantly higher than premature CVD deaths in the U.S. (23%). Most CVD deaths were due to ischemic heart disease (IHD) or stroke. According to the researchers, increasing CVD epidemics in Asia are due to demographic changes, socioeconomics, living environments, lifestyles, prevalence of CVD risk factors and capacities to prevent and treat CVD.

In this paper, authors reviewed data on CVD epidemiology in Asian countries from multiple sources and identified five epidemiological features in Asia: continuously increasing CVD mortality rate; geographic differences in CVD mortality; regional differences in the dominant CVD subtype; countries that are in different transition stages of the CVD epidemic; and the increasing epidemics and massive burdens of key modifiable CVD risk factors in most countries with inadequate capacities for management.

"Timely information on the burdens and epidemiological features of CVD in Asian countries is crucial to understanding the challenges and orienting the development of reasonable policies strategies and actions to combat the CVD epidemic," said Dong Zhao, MD, PhD, professor of preventive cardiology at the Beijing Institute of Heart, Lung and Blood Vessel Diseases at Beijing Anzhen Hospital, Capital Medical University, and a deputy editor of JACC: Asia.

From 1990-2019, the proportion of CVD deaths among total deaths in Asia increased from 23% to 35%, and crude CVD mortality rates grew in both men and women. The rising crude CVD mortality rates indicate the increasing burden of CVD in Asian populations.

There were significant geographic differences in crude CVD mortality rates among Asian countries in 2019. The highest CVD mortality rate in Asia was in Georgia (810.7 per 100,000 population) and the lowest was in Qatar (39.1 per 100,000 population), representing a 20-fold difference.

While IHD and stroke are the most common causes of CVD in Asia, epidemics of these two types of CVD varied substantially between Asian regions and countries. IHD was the most dominant cause of CVD deaths in Central, Western and Southern Asia, whereas deaths from stroke were more common than IHD deaths in Eastern and Southeastern Asia. In China, the dominant subtype of CVD deaths has shifted from stroke to IHD. According to the authors, the underlying cause of the differences in the dominant CVD subtypes among Asian regions or countries is still not well understood.

The paper also compared the characteristics of CVD spectrums (the distributions of relevant disease categories in total deaths) in low-, middle- and high-income (or developed) Asian countries since countries at different stages of economic development may feature different transition stages of the CVD epidemic.

"It is critical to recognize the characteristics of different transition stages of the CVD epidemic in different Asian countries in order to guide the identification of priority issues in public health, resource allocation and research in these countries," Zhao said.

Most Asian countries are in the second stage of the rapidly increasing CVD epidemic. In these countries like China, CVD mortality rates are relatively high, with the proportion of CVD deaths among total deaths generally greater than 40%. Characteristics of CVD epidemics in high-income or developed countries feature the third stage of the epidemiological transition, with lower proportions of CVD deaths. In Japan and South Korea, the proportions of CVD deaths among total deaths decreased from 34.9% and 36.2% in 1990, to 26.6% and 24.3% in 2019, respectively.

According to the researchers, the increasing prevalence of CVD risk factors is a major modifiable cause of the rising CVD epidemics in Asia. These risk factors include dietary, smoking, dyslipidemia, diabetes and hypertension, among many others.

"The information summarized in this review provides a complete picture of CVD epidemiology in Asia, highlighting specific requirements for the development of localized CVD prevention strategies and research, and may illuminate not only the current but also future challenges faced by different Asian countries," Zhao said.

There is increasing scrutiny around how science is communicated to the public, but what is the relationship between how scientists report their findings and how media reports it to the public? A study published in PLOS Biology by Marcia Triunfol at Humane Society International, in Washington, DC and Fabio Gouveia at Oswaldo Cruz Foundation in Rio de Janeiro, Brazil suggests that when authors of scientific papers omit the basic fact that a study was conducted in mice (and not in humans) from the article title, journalists reporting on the paper tend to do the same.

Alzheimer's Disease is an exclusively human condition that does not occur naturally in other species, but around 200 rodent models have been developed to study it. News stories frequently lead with headlines omitting that Alzheimer's Disease research findings are based on research using mice, not humans.

To test the hypothesis that how scientists report their research plays a role in the news reporting, the researchers analyzed 623 scientific papers published in 2018 and 2019 that used mice either as models or as the biological source for experimental studies in Alzheimer's Disease research. They then divided the papers into two groups; those that declared in their titles that mice were the study's main species, and those that omitted mice from the paper's title. The authors analyzed whether there was any difference between these groups regarding the number of news stories each paper generated.

The researchers found an association between articles' titles and news stories' headlines, suggesting that journalists tend to follow authors' decision to omit the species studied in the paper's title. They also found that papers not mentioning mice in their titles receive more press coverage and are significantly more highly tweeted than papers that do. The study had several limitations, including that the articles analyzed only included open access publications. Additionally, findings cannot be extended to other fields before a careful analysis is done.

According to the authors, "To our knowledge, this is the first study to present scientific evidence that the way science is reported by scientists plays a role in how journalists report science news. News stories' headlines that omit mice as the main study subject may mislead the public regarding the actual state of affairs in Alzheimer's Disease research while raising false hopes for patients and their families".

Dr. Triunfol notes, "We need to remember that most people only read the headlines of news stories. Thus, if the headline omits that the Alzheimer's study was done in mice, most keep the impression that the study findings apply to humans, which is not true. We now know that virtually all findings obtained in animal studies in Alzheimer's Disease do not replicate to humans".

Dr. Triunfol adds, "In a follow up study we will investigate why scientists choose to omit mice from their studies' titles. In this article we raised some hypothesis".

Killer whales have complex social structures including close "friendships", according to a new study that used drones to film the animals.

The findings show that killer whales spend more time interacting with certain individuals in their pod, and tend to favour those of the same sex and similar age.

The study, led by the University of Exeter and the Center for Whale Research (CWR), also found that the whales become less socially connected as they get older.

"Until now, research on killer whale social networks has relied on seeing the whales when they surface, and recording which whales are together," said lead author Dr Michael Weiss, of the University of Exeter.

"However, because resident killer whales stay in the social groups into which they're born, how closely related whales are seemed to be the only thing that explained their social structure.

"Looking down into the water from a drone allowed us to see details such as contact between individual whales.

"Our findings show that, even within these tight-knit groups, whales prefer to interact with specific individuals.

"It's like when your mom takes you to a party as a kid - you didn't choose the party, but you can still choose who to hang out with once you're there."

Patterns of physical contact - one of the social interactions the study measured - suggest that younger whales and females play a central social role in the group. The older the whale, the less central they became.

The new research built on more than four decades of data collected by CWR on southern resident killer whales, a critically endangered population in the Pacific Ocean.

"This study would not have been possible without the amazing work done by CWR," said Professor Darren Croft, of Exeter's Centre for Research in Animal Behaviour.

"By adding drones to our toolkit, we have been able to dive into the social lives of these animals as never before.

"We were amazed to see how much contact there is between whales - how tactile they are.

"In many species, including humans, physical contact tends to be a soothing, stress-relieving activity that reinforces social connection.

"We also examined occasions when whales surfaced together - as acting in unison is a sign of social ties in many species.

"We found fascinating parallels between the behaviour of whales and other mammals, and we are excited about the next stages of this research."

The omega-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are found in oily fish. Researchers from the National Institute of Health Research (NIHR) Maudsley Biomedical Research Centre assessed the effects of high doses of EPA and DHA in lab-grown neurones and then in patients to help clarify how they reduce inflammation and depression. This novel approach allowed the scientists to identify an important molecular mechanism which can help inform the development of potential new treatments involving omega-3 fatty acids for patients with depression.

Lead author Dr Alessandra Borsini, NIHR Maudsley BRC Senior Postdoctoral Neuroscientist at King's College London, said: "Using a combination of laboratory and patient research our study has provided exciting new insight into how omega-3 fatty acids bring about anti-inflammatory effects that improve depression. For some time we have known that omega-3 PUFA can induce anti-depressant and anti-inflammatory effects but, without further understanding of how this happens in the human brain, it has been difficult to develop treatments. Our study has helped shine a light on the molecular mechanisms involved in this relationship which can inform the development of potential new treatments for depression using omega-3 PUFA."

Previous research has shown that people with major depressive disorder have higher levels of inflammation in their bodies than those without the disorder. There are currently no proven anti-inflammatory treatment strategies for depression and, although two important omega-3 PUFAs, EPA and DHA, have been shown to provide anti-inflammatory and antidepressant effects, the precise mechanism by which they do this is unknown.

Depression in a dish
The study set out to test the theory that when omega-3 fatty acids are utilised and processed in the body, some of their metabolites (known as lipid mediators) are able to protect the brain from the harmful effects of inflammation. Researchers used a validated in vitro human cell model known as 'depression in a dish' that was developed at the NIHR Maudsley Biomedical Research Centre and which uses cells from the hippocampus, a part of the brain fundamental in many cognitive, memory and learning areas thought to be important in depression. Hippocampal cells play an important role in the production of new neurones - neurogenesis.

The study showed that treating human hippocampal cells with EPA or DHA before being exposed to chemical messengers involved in inflammation called cytokines, prevented increased cell death and decreased neurogenesis. Both these impacts had been previously observed in cells exposed to cytokines alone. Further investigation confirmed these effects were mediated by the formation of several key lipid mediators produced by EPA and DHA, namely hydroxyeicosapentaenoic acid (HEPE), hydroxydocosahexaenoic acid (HDHA), epoxyeicosatetraenoic acid (EpETE) and epoxydocosapentaenoic acid (EpDPA), and these were detected for the first time in human hippocampal neurones. Further investigation showed that treatment with an enzyme inhibitor increased the availability of two of these metabolites (EpETE and EpDPA) suggesting a possible way by which future treatments could be optimised.

Professor Anna Nicolaou, professor of Biological Chemistry at the Faculty of Medical and Human Sciences, The University of Manchester, who led the team that measured the lipid mediators using mass spectrometry said: "The lipid mediators that our research identified are broken down in the body relatively quickly, which means they may only be available for a relatively short time. By testing the effect of inhibitors of the enzymes involved in the metabolism of omega-3 PUFA we showed that we can greatly improve how long they can have an effect in the body and ultimately, increase their efficacy. This is very important for the development of new treatments and means that patients could be given higher doses of EPA and DHA together with these enzyme inhibitors to increase the amount of these important compounds in their blood over time."

Omega-3 metabolites in patients

The study assessed twenty-two patients with major depression who were given either 3 grams of EPA or 1.4 grams of DHA daily for twelve weeks. The lipid metabolites of EPA and DHA were measured in their blood before and after the omega-3 PUFA treatment, along with a score of their depressive symptoms. In both groups of patients, EPA or DHA treatment was associated with an increase in their respective metabolites and a significant improvement in depressive symptoms - an average reduction in symptom scores of 64% and 71% in the EPA and DHA groups respectively. In addition, higher levels of the same metabolites identified in the in vitro experiments were correlated with lower levels of depressive symptoms.

The levels of EPA and DHA used in this study are concentrations that most likely cannot be achieved with dietary consumption of oily fish, a rich source of omega-3 PUFAs, but require therapeutic supplements.

Future Research

The results of the study indicate that the bioactive lipid mediators produced by the breakdown of EPA and DHA in the body could be targeted as a mechanism to reduce depression and inflammation but there is a need to ensure that their effects are prolonged in order for this approach to be successful. Previous research indicates a key enzyme in the omega-3 fatty acid metabolism could be a valid option for drug repurposing and could be used for other inflammation-associated brain disorders, including depression, where at least a sub-group of patients often have chronic levels of inflammation.

Senior author of the paper, Professor Carmine Pariante, NIHR Maudsley BRC Affective Disorders Interface with Medicine Theme Lead said: "There is ever growing interest in the links between the immune system, inflammation and depression but in order to develop new treatments in this area we need to better understand the mechanisms behind these relationships. Our study has provided important insight into how known anti-inflammatory compounds - the omega-3 PUFA - help reduce depression. By identifying and measuring the exact lipid mediators that are involved, identifying the enzyme that prolongs their effects and finding the same lipid mediators in depressed patients treated with omega-3 PUFA and demonstrating improvements in symptoms, we have provided vital information to help shape clinical trials for future therapeutic approaches with omega-3 fatty acids.

"It is important to highlight that our research has not shown that by simply increasing omega-3 fatty acids in our diets or through taking nutritional supplements we can reduce inflammation or depression. The mechanisms behind the associations between depression and omega-3 PUFA are complicated and require further research and clinical trials to fully understand how they work and inform future therapeutic approaches."

The study was a collaboration between researchers from King's College London, The University of Manchester and China Medical University.

The paper Omega-3 polyunsaturated fatty acids protect against inflammation through production of LOX and CYP450 lipid mediators: relevance for major depression and for human hippocampal neurogenesis was published today (Wednesday 16 June) in Molecular Psychiatry.