Culture

A new Boston University School of Public Health study of the first four months of America's coronavirus epidemic, published in the journal Nature Human Behaviour, shows that physical distancing (also called "social distancing") policies had little effect on lower income people still needing to leave their homes to go to work--but does show them staying home when they could.

"If lower-income people were simply ignoring the trend towards physical distancing, we would have expected them to continue going to places like supermarkets, liquor stores, and parks at the same rates as before. Instead, their visits dropped at almost the same rates as the very highest-income group," says study lead author Dr. Jonathan Jay, assistant professor of community health sciences at BUSPH.

"This indicates that lower income people were just as aware and motivated as higher-income people to protect themselves from COVID-19, but simply couldn't stay home as much because they needed to go to work," he says.

Jay and colleagues used anonymized mobility data from smartphones in over 210,000 neighborhoods (census block groups) across the country, each neighborhood categorized by average income. They were able to see whether people from these neighborhoods stayed home, left home and appeared to be at work--staying at another location for at least three hours during typical working hours, or making multiple stops that looked like delivery work. The researchers also tracked movement to "points of interest": beer, wine and liquor stores; carryout restaurants; convenience stores; hospitals; parks and playgrounds; places of worship; and supermarkets.

"The difference in physical distancing between low- and high-income neighborhoods during the lockdown was just staggering," says study co-author Dr. Jacob Bor, assistant professor of global health and epidemiology at BUSPH.

"While people in high-income neighborhoods retreated to home offices, people in low-income neighborhoods had to continue to go to work--and their friends, family, and neighbors had to do the same," he says. "Living in a low-income neighborhood is likely a key risk factor for COVID-19 infection."

To analyze the role that policies played in these mobility patterns, the researcher used the COVID-19 U.S. State Policy Database (CUSP), a project led by study co-author Dr. Julia Raifman, assistant professor of health law, policy & management at BUSPH.

They found that the huge drop in mobility early in March had little to do with state policy, following similar patterns in different states regardless of when their orders went into effect. When state policies did go into effect, they modestly decreased mobility further--but did nothing to close the gap between low- and high-income neighborhoods.

"The orders did not have the effect of making it easier for lower-income people to stay home," Jay says. But they did stay home to the degree possible, visiting non-work non-home locations less--which counters a major narrative about how different groups of people have responded to COVID, Jay says. "Early in the pandemic, there was a lot of talk about 'non-compliance,' and it was rarely directed at the people with the most power and privilege," he says.

"We found strong evidence of compliance among the people who are most economically marginalized, which because of structural racism disproportionately includes people of color. As the pandemic has played out, the evidence of poor safety practices at the very highest levels of power has become more clear.

"Still, it's deeply troubling that throughout the pandemic, staying home has been a choice for some people and not for others."

The researchers say that closures are an important tool for states and cities to prevent the spread of the coronavirus, but that they need to be accompanied by other policies that make it easier for frontline workers to protect themselves.

"That people living in low-income households are more likely to face exposure to COVID-19 at work increases the importance of complementary policies, such as mask requirements in indoor spaces, that protect essential workers from COVID-19," Raifman says.

"One of the most important arguments for mask mandates is that they protect the folks who are in public spaces not because they want to be, but because showing up is how they make ends meet," Jay says. He also points to "policies that make it easier to work from home, stay home sick, and not to take a risky new job just to put food on the table."

However, Jay says, policies that make it easier to stay home only help if people have homes. As a wave of evictions and foreclosures sweeps the country, he says extending moratoriums and enacting other housing policies continue to be an important part of the picture.

MIAMI--A new study by researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science projects an increase in Florida's late summertime rainfall with rising Atlantic Ocean temperatures.

Scientists have known for years that Florida receives more rainfall in decades when North Atlantic waters are warmer than average, but the UM research team wanted to learn more about this interaction to help communities prepare for a wetter future. This study showed that ocean temperatures are most influential on Florida precipitation in late summer, during the region's highest high tide events.

The researchers used a suite of climate models to show that the link between ocean temperatures and rainfall only develops as a result of human influences on the climate system, such as greenhouse gas emissions and industrial pollution.

"We know that humans are continuing to make North Atlantic waters warmer, so we expect an increase in late summer rainfall in Florida in the future," said Jeremy Klavans, a PhD student at the UM Rosenstiel School and lead author of the study.

The study, titled "Identifying the Externally?forced Atlantic Multidecadal Variability Signal through Florida Rainfall" was published in the early online edition of the American Geophysical Union's journal Geophysical Research Letters. The study's coauthors include: Jeremy Klavans, Amy Clement and Lisa Murphy from the UM Rosenstiel School; and Honghai Zhang, a UM Rosenstiel School alumni currently at Columbia University's Lamont?Doherty Earth Observatory.

AMHERST, Mass. - In a new paper with results that senior author Eric Strieter at the University of Massachusetts Amherst calls "incredibly surprising," he and his chemistry lab group report that they have discovered how an enzyme known as UCH37 regulates a cell's waste management system.

Strieter says, "It took us eight years to figure it out, and I'm very proud of this work. We had to develop a lot of new methods and tools to understand what this enzyme is doing."

As he explains, a very large protease called a proteasome is responsible for degrading the vast majority of proteins in a cell; it may be made up of as many as 40 proteins. It has been known for more than 20 years that UCH37 is one of the regulatory enzymes that associates with the proteasome, he adds, "but no one understood what it was doing."

It turns out that the crux of the whole process, he adds, is how complicated modifications in a small protein called ubiquitin can be. "In addition to modifying other proteins, ubiquitin modifies itself resulting in a wide array of chains. Some of these chains can have extensive branching. We found that UCH37 removes branchpoints from chains, allowing degradation to proceed."

Writing this week in Molecular Cell, he and first author and Ph.D. candidate Kirandeep Deol, who led and conducted the experiments, with co-authors Sean Crowe, Jiale Du, Heather Bisbee and Robert Guenette, discuss how they answered the question. The work was supported by the NIH's National Institute of General Medical Sciences.

This advance could eventually lead to a new cancer treatment, Strieter says, because cancer cells need the proteasome to grow and proliferate. "Many cancer cells are essentially addicted to proteasome function," he points out. "Its cells produce proteins at such a fast rate that mistakes are made, and if these are not cleared out, cells can't function. Since UCH37 aids in clearing out proteins, it could be a useful therapeutic target to add to the proteasome inhibitors that have already been successful in the clinic."

To begin their years-long process, Strieter says, "we had to come up with a way to generate a wide variety of ubiquitin chains that would represent the potential diversity in a cell. Using that new library of ubiquitin chains allowed us to interrogate the activity of UCH37 in a controlled setting. That series of experiments gave us the first clue that this enzyme was doing something unique."

Another new method they developed uses mass spectrometry to characterize the architecture of ubiquitin chains in complex mixtures. "This allowed us to see that the activity we discovered with our library of substrates was also present in a more heterogenous mixture," Strieter says. Finally, the chemists used the CRISPR gene editing tool to remove UCH37 from cells to measure the impact of UCH37 on proteasome-mediated degradation in vitro and in cells.

This technique led to one more surprise. "Instead of acting as expected and opposing the degradation process, it turned out that UCH37 was removing branchpoints from ubiquitin chains to help degrade proteins," Strieter says. "You would think that by removing the signal for degradation that degradation would be impaired," he adds, "but it didn't work that way."

In future experiments, Strieter and colleagues hope to further explore the degradation process and learn in more detail how UCH37 manages to regulate cellular function.

The effect of dopaminergic medication on the learning abilities of patients with Parkinson's disease turns out to be linked to the presence of tremor symptoms. In patients who do not experience tremor, dopaminergic medication improves the ability to learn from rewards (reinforcement learning). Remarkably, the medication brings no benefit in reward learning to patients who do exhibit tremor. These were the results from a new study by brain researchers at the Donders Institute of Radboud University and Radboud university medical center, published on 6 November in the scientific journal Brain.

"It is somewhat surprising that until now, studies of cognition in Parkinson's disease never assessed the distinction between patients who exhibit tremor and those who do not", says Hanneke den Ouden, brain researcher at Radboud University. "Our study shows that there is a link between problems with motor skills and problems with cognition in patients with Parkinson's disease."

Learning abilities and Parkinson's disease
Most patients with Parkinson's disease experience tremor -shaking in an arm or leg. Only one in four patients does not experience these symptoms. In addition, many patients experience mental issues. Due to a decrease in dopamine, a chemical messenger molecule that occurs in the brain, patients with Parkinson's disease become less sensitive to learning through rewards.

A large number of prior studies have shown that this learning disorder can be remedied by administering dopaminergic medication. It remained a mystery, however, why medication had no effect in many patients. The study of the Radboud researchers reveals that this improvement through medication only occurs in patients who do not experience tremor.

Presence and absence of tremor

"We observed that, with medication, patients without tremor got better at a task in which they had to learn to push a button in order to receive a reward (points). This result fully agrees with prior research. However, remarkably enough, patients with tremor would exhibit an opposite effect", Den Ouden says. "Importantly, patients without tremor generally exhibit a faster deterioration of the cognitive abilities and are more likely to develop dementia, for example."

"The fact that we only observe results from earlier studies in patients without tremor suggests that prior studies only included these patients. This would make sense, as it is easier for patients without tremor to participate in an experiment. However, it is important to realise that three out of four patients actually do experience tremor, and our study shows that the medication has a different effect on these patients. We see this as a major warning: Always be aware of the diversity of patients in your study, as you might otherwise draw the wrong conclusions."

Predictive value

According to the researchers, it is crucial to improve our understanding of such patient diversity. "This study tells us that the dopamine systems of Parkinson's disease patients with and without tremor are affected in different ways, and that this goes beyond the level of just motor problems, affecting cognition as well", according to co-author Rick Helmich, neurologist at Radboud university medical center. "Whether someone experiences tremor or not might therefore potentially have a significant predictive value regarding the effectiveness of medication in the cognitive domain. However, more and larger studies are needed before this can be confirmed."

Subarachnoid haemorrhage (SAH), the most fatal of all cerebrovascular disturbances, results in death for 40-50% of patients suffering from the condition in the first months after the haemorrhage.

The annual incidence of SAH is considered to be six to seven cases per 100,000 people globally. Due to its rarity, the effects of this cerebral haemorrhage type have been considered very minor on the population level. Furthermore, it has been previously estimated that no more than 4% of all deaths caused by strokes are caused by SAH.

Although the disease has been known to be most prevalent among the middle-aged population, it has been impossible to reliably determine the share of deaths among the working-age population caused by subarachnoid haemorrhage: As many as a quarter of SAH patients die before reaching the hospital, and many countries record the deaths of such SAH patients according to more likely causes, for example, as sudden cardiac deaths. If an autopsy is not conducted in the case of sudden death, the cause of death and the possibility of SAH remain undetermined.

In Finland, autopsies are mandated by law to be conducted to determine the cause of death in cases of sudden death. This has enabled Finnish researchers to determine, for the first time, the share of deaths caused by subarachnoid haemorrhage in all deaths of middle-aged people.

The registry study, which was recently published in the Journal of Neurology, Neurosurgery and Psychiatry (JNNP), included precise details on the cause of death for almost 200,000 individuals between the ages of 40 and 65 who have died in Finland in the past 20 years.

The results indicate that, in middle-aged women, subarachnoid haemorrhage was the 12th most common cause of death from among all deaths and the most common type of stroke death throughout the entire 20-year study period.

More middle-aged women die from subarachnoid haemorrhage than in car crashes or from cerebral infarctions

According to Ilari Rautalin, the principal investigator, the finding is a surprise in the light of previous literature.

"In middle-aged women in particular, the number of SAH deaths clearly exceeds that of deaths caused by cerebral infarctions, deaths from several cancers and, for example, car crashes and other accidents," says Rautalin, Bachelor of Medicine, who is also a PhD student.

As SAH is a disease primarily caused by smoking and high blood pressure, it is largely preventable.

"Investment in healthy lifestyles would cut down significantly the share of premature deaths among the working-age population," says Rautalin.

The other two members of the research group and authors of the article, Miikka Korja, docent and neurosurgeon at Helsinki University Hospital, and Jaakko Kaprio, professor of genetic epidemiology at the University of Helsinki, also emphasise the importance of a healthy lifestyle.

According to them, premature deaths among the working-age population could be effectively prevented, for example, by encouraging people to not smoke and by preventing hypertension as well as by providing them with good care.

Extensive registers provide information on fatal cerebral haemorrhage

The study of deaths among Finnish middle-aged people is based on population-level registers maintained by Statistics Finland and the Finnish Institute for Health and Welfare. The registers make it possible to carry out comprehensive studies on subarachnoid haemorrhage in Finland.

"There have been digital health registers in use in Finland from the 1960s. Finland's high-quality healthcare system and a number of related top-level registers that cover the entire population are the reason why Finland has produced so many groundbreaking studies on subarachnoid haemorrhage," says Docent Korja, who heads the group.

Recently, the group published a finding on the effect of smoking on subarachnoid haemorrhage, and they have now uncovered new information on the share of SAH deaths among middle-aged people. However, the significance of several risk factors potentially associated with SAH remains unknown.

"The topic is in urgent need of high-quality research evidence based on the health records of hundreds of thousands of individuals and decades-long monitoring periods," Rautalin says.

What The Study Did: The association between patient demographic characteristics and socioeconomic status and engagement in telemedicine during the COVID-19 pandemic is examined in this observational study.

Authors: Samantha Tam, M.D., M.P.H., of the Henry Ford Health System and Henry Ford Cancer Institute in Detroit, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamaoto.2020.3052)

Editor's Note: The article includes conflict of interest disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflicts of interest and financial disclosures, and funding and support.

What The Study Did: National health record data were used to examine whether the rate of positive tests for variants of the BRCA gene that increase the risk for certain cancers changed among older women in the United States between 2008 and 2018.

Authors: Fangjian Guo, M.D., Ph.D., of the University of Texas Medical Branch at Galveston, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2020.24358)

Editor's Note: The article includes funding/support disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

NEUROSCIENCE EXPERTS from the University of Leicester have released research that breaks with the past fifty years of neuroscientific opinion, arguing that the way we store memories is key to making human intelligence superior to that of animals.

It has previously been thought and copiously published that it is 'pattern separation' in the hippocampus, an area of the brain critical for memory, that enables memories to be stored by separate groups of neurons, so that memories don't get mixed up.

Now, after fifteen years of research, Leicester University's Director of Systems Neuroscience believes that in fact the opposite to pattern separation is present in the human hippocampus. He argues that, contrary to what has been described in animals, the same group of neurons store all memories. The consequences of this are far reaching, as such neuronal representation, devoid of specific contextual details, explains the abstract thinking that characterizes human intelligence.

Leicester University's Director of Systems Neuroscience Professor Rodrigo Quian Quiroga explains,

"In contrast to what everybody expects, when recording the activity of individual neurons we have found that there is an alternative model to pattern separation storing our memories.

"Pattern separation is a basic principle of neuronal coding that precludes memory interference in the hippocampus. Its existence is supported by numerous theoretical, computational and experimental findings in different animal species but these findings have never been directly replicated in humans. Previous human studies have been mostly obtained using Functional Magnetic Resource Imagining (fMRI), which doesn't allow recording the activity of individual neurons. Shockingly, when we directly recorded the activity of individual neurons, we found something completely different to what has been described in other animals. This could well be a cornerstone of human's intelligence."

The study, 'No pattern sepaeration in the human hippocampus', argues that the lack of pattern separation in memory coding is a key difference compared to other species, which has profound implications that could explain cognitive abilities uniquely developed in humans, such as our power of generalization and of creative thought.

Professor Quian Quiroga believes we should go beyond behavioural comparisons between humans and animals and seek for more mechanistic insights, asking what in our brain gives rise to human's unique and vast repertoire of cognitive functions. In particular, he argues that brain size or number of neurons cannot solely explain the difference, since there is, for example, a comparable number and type of neurons in the chimp and the human brain, and both species have more or less the same anatomical structures. Therefore, our neurons, or at least some of them, must be doing something completely different, and one such difference is given by how they store our memories.

Expansion of Medicaid eligibility under the Affordable Care Act is associated with decreased mortality for patients with newly diagnosed breast, lung, or colorectal cancer.

The mortality improvement was due to earlier stage of diagnosis in states that have expanded Medicaid.

BOSTON - In states that have expanded Medicaid availability as part of the Affordable Care Act (ACA), mortality rates for three major forms of cancer are significantly lower than in states that have not expanded their Medicaid, a new study by researchers at Dana-Farber Cancer Institute, Brigham and Women's Hospital, and Harvard University shows.

Data from the study, published online today in JAMA Network Open, suggest that the improvement in mortality results from cancers being diagnosed at an earlier stage in states with Medicaid expansion. Early detection of cancer is often critical to successful treatment of the disease.

The ACA, passed in 2010, gave states the option of expanding eligibility for Medicaid - the government-funded health insurance program for low-income families and individuals - to nonelderly adults with incomes at or below 138% of the federal poverty level. Previous studies involving cancer patients have shown Medicaid expansion to be associated with fewer uninsured patients, increased screening, and stage of disease diagnosis. (Currently, 39 states have expanded Medicaid programs.)

"There has been little research into the impact of Medicaid expansion on cancer mortality [the time from initial cancer diagnosis to death]," says the lead author of the new study, Miranda Lam, MD, MBA, of Dana-Farber, Brigham and Women's Hospital, and Harvard T.H. Chan School of Public Health. "It's been thought that expansion might improve mortality by fostering earlier detection, earlier stage of diagnosis, and improved access to treatment. On the other hand, it could worsen mortality by creating an influx of newly covered patients that strains hospitals' resources."

For the study, researchers used the National Cancer Database to track 523,802 patients across the country who were newly diagnosed with breast, lung, or colorectal cancer from 2012 through 2015. They compared mortality rates for these patients in states that expanded their Medicaid programs and those that did not. (Twenty-four states and the District of Columbia expanded their programs on Jan. 1, 2014.)

"We found that Medicaid expansion was associated with a significant decrease in mortality compared to states without such expansion," Lam remarks. The expansion group had a 2% decline in hazard of death from the pre- to the post-expansion period. The non-expansion group, by contrast, showed no change in mortality.

If the 2% reduction was achieved in all states with expanded Medicaid, then among the approximately 69,000 patients diagnosed with cancer in those states, 1,384 lives would be saved yearly, researchers calculated.

The biggest difference between the two groups was in patients whose cancers hadn't reached a metastatic stage and are considered curable. When investigators adjusted for the stage at which cancers were diagnosed, improvements in mortality were no longer seen - whether between expansion and non-expansion states or between the pre-expansion and post-expansion period. This suggests that the decline in mortality associated with Medicaid expansion is a byproduct of diagnosing cancer at an earlier stage.

"Increased Medicaid coverage may remove barriers to accessing the healthcare system for screening and timely symptom evaluation, and that can translate into better outcomes for patients," Lam comments.

The investigators also found that the decrease in mortality in Medicaid-expansion states occurred across population groups. "We were reassured to find that patients living in areas of the lowest quartile of median household income showed a modest decrease in mortality after Medicaid expansion," Lam observes. "We also found that the mortality improvements occurred in both Black and white populations."

A new global analysis led by Imperial College London, and published in journal The Lancet, has assessed the height and weight of school-aged children and adolescents across the world.

The study, which used data from 65 million children aged five to 19 years old in 193 countries, revealed that school-aged children's' height and weight, which are indicators of their health and quality of their diet, vary enormously around the world.

There was a 20 cm difference between 19-year-olds in the tallest and shortest nations - this represented an eight-year growth gap for girls, and a six-year growth gap for boys. For instance, the study revealed that the average 19-year-old girl in Bangladesh and Guatemala (the nations with the world's shortest girls) is the same height as an average 11-year-old girl in the Netherlands, the nation with the tallest boys and girls.

The international team behind the study warn that highly variable childhood nutrition, especially a lack of quality food, may lead to stunted growth and a rise in childhood obesity - affecting a child's health and wellbeing for their entire life.

The research, which reported data from 1985 to 2019, revealed that the nations with the tallest 19-year-olds in 2019 were in northwest and central Europe, and included the Netherlands, Montenegro, Denmark and Iceland.

These nations with the shortest 19-year-olds in 2019 were mostly in south and southeast Asia, Latin America and East Africa, including Timor-Leste, Papua New Guinea, Guatemala and Bangladesh.

The largest improvements in average height of children over the 35-year period were seen in emerging economies such as China, South Korea and some parts of southeast Asia. For example, 19-year old boys in China in 2019 were 8 cm taller than in 1985, with their global rank changing from 150th tallest in 1985 to 65th in 2019. In contrast the height of children, especially boys, in many Sub-Saharan African nations has stagnated or reduced over these decades.

Global height ranking for UK has worsened over past 35 years, with 19-year-old boys falling from 28th tallest in 1985 (176.3 cm) to 39th in 2019 (178.2 cm), and 19-year-old girls from 42nd (162.7 cm) to 49th (163.9 cm).

The study also assessed children's Body Mass Index (BMI) - a measure of height to weight ratio, which gives an indication of whether a person has a healthy weight for their height. The analysis found that 19-year-olds with the largest BMI were found in the Pacific islands, Middle East, USA and New Zealand. The BMI of 19-year-olds was lowest in south Asian countries such as India and Bangladesh. The difference between the lightest and the heaviest BMIs in the study was around 9 units of BMI (equivalent to around 25 kg of weight).

The research team explain the analysis also revealed that, in many nations, children at age five had a height and weight in the healthy range defined by the World Health Organization (WHO). However, after this age, children in some countries have experienced too small an increase in height, and gained too much weight, compared to the potential for healthy growth.

The team say the most important reason for this is the lack of adequate and healthy nutrition and living environment in the school years, as both height and weight gains are closely linked to the quality of a child's diet.

Professor Majid Ezzati, senior author of the study from Imperial's School of Public Health said: "Children in some countries grow healthily to five years, but fall behind in school years. This shows that there is an imbalance between investment in improving nutrition in pre-schoolers, and in school-aged children and adolescents. This issue is especially important during the COVID-19 pandemic when schools are closed throughout the world, and many poor families are unable to provide adequate nutrition for their children."

Dr Andrea Rodriguez Martinez, the lead author of the study from Imperial's School of Public Health, added: "Our findings should motivate policies that increase the availability and reduce the cost of nutritious foods, as this will help children grow taller without gaining excessive weight for their height. These initiatives include food vouchers towards nutritious foods for low-income families, and free healthy school meal programmes which are particularly under threat during the pandemic. These actions would enable children to grow taller without gaining excessive weight, with lifelong benefits for their health and wellbeing."

Asian ethnicity is strongly linked to COVID-related stroke, reveals an analysis of stroke centre activity in England and Scotland during the first wave of the coronavirus pandemic, and accepted for publication in the Journal of Neurology Neurosurgery & Psychiatry.

Among patients with ischaemic stroke, which is caused by a blocked artery, nearly 1 in 5 (20%) of those with COVID-19 infection when they had their stroke were Asian--more than twice the proportion seen in ischaemic stroke patients without COVID-19.

Ischaemic strokes were also more extensive and severe, and more likely to result in greater disability and death, when associated with COVID-19, the findings indicate.

Previous research has suggested that COVID-19 infection might make the blood stickier and so more liable to clot, so potentially boosting the risk of a stroke, but this finding has been undermined by the poor quality of the evidence to date and the reliance on comparisons with historical stroke data.

To obtain a clearer real-time picture of the potential impact of COVID-19 on stroke risk, the researchers collected data for 1470 strokes among patients admitted to 13 hospitals between March and July this year, during the first wave of the coronavirus pandemic.

During this period, there were 86 strokes in patients with evidence of COVID-19 at the time: 81 of these strokes were ischaemic (caused by blocked blood vessels); the remainder were intracerebral haemorrhages (caused by burst blood vessels).

Evidence of infection was determined by a positive coronavirus test within 4 days of admission or suspected COVID-19 at the time of admission and confirmed on testing at any point during the subsequent 10 days.

The features of these 'COVID' strokes were compared with 1384 (1193 ischaemic and 191 intracerebral) among patients admitted during the same time period, but with no evidence of COVID-19.

Ethnicity was recorded in 86% of COVID cases and 78% of non-COVID cases. Among patients with ischaemic stroke nearly 1 in 5 (19%) of those with COVID-19 infection when they had their stroke were Asian--more than twice the proportion seen in ischaemic stroke patients without COVID-19 (7%).

This rate was higher than that seen in people of Afro-Caribbean ethnicity. *Lead study author, Dr Richard Perry, comments: "Our study suggests that COVID-19 has had more impact on strokes in the Asian community than in other ethnic groups. We cannot say from our data whether this is because Asians are more likely to catch COVID-19, but it seems unlikely that this is the sole explanation.

"Evidence from Public Health England suggests that, in the UK, people of Afro-Caribbean origin are at the highest risk of catching COVID-19, whereas those of Asian descent have only a marginally higher risk than White people. We suspect, therefore, that Asian people who contract COVID-19 may have a higher risk of COVID-19-associated stroke than is seen in other ethnic groups."

Ischaemic strokes in COVID patients were around twice as likely to be caused by the blockage of more than one large blood vessel in the brain (18% vs 8%), and to be more severe, with an average stroke severity (NIHSS) score of 8 vs 5.

Levels of D-dimers, a protein marker for the stickiness of blood, were also higher in COVID-19-related strokes than in other strokes.

Ischaemic strokes in COVID-19 patients were associated with more severe disability on discharge--average disability score of 5 (out of a possible 6)--and death while in hospital (20% vs 10%), even after accounting for other influential risk factors.

In the 45 COVID patients who had had an ischaemic stroke, and for whom both dates were recorded, cardinal COVID-19 symptoms occurred an average of 6 days before the stroke.

Among the 3 patients who had a brain bleed, and for whom both dates were recorded, COVID-19 symptoms occurred an average of 4 days after the stroke. Although the numbers are small, this difference is significant, say the researchers.

They found no evidence to back up previous suggestions that SARS-CoV-2, the virus responsible for COVID-19 infection, is associated with younger age or male sex in stroke patients.

The researchers acknowledge that a major limitation of their study was that they were only able to report investigations done as part of routine clinical care. But they included patients from 13 centres across the UK, so it may be more representative than existing studies from a single hospital system or city, they suggest.

"These findings...confirm that COVID-19 has an important influence over the onset, characteristics and outcome of acute ischaemic stroke," they write. How the virus exerts its influence is still unclear, but one single factor is unlikely to be responsible, they explain.

"We suggest that COVID-19 may provoke the onset of an ischaemic stroke through a variety of thrombotic [clot forming] and inflammatory mechanisms, promoting generation of thrombus [blood clot] in the heart or large vessels or via small vessel occlusion [blockage]," they write.

"Which of these mechanisms manifests in a given patient may be determined by that individual's conventional vascular risk factors, such as atrial fibrillation [abnormal heart beat], large vessel atheroma [artery narrowing], hypertension [high blood pressure] or type 2 diabetes mellitus."

And they conclude: "Our study provides the most compelling evidence yet that COVID-19-associated ischaemic strokes are more severe and more likely to result in severe disability or death, although the outlook is not quite as bleak as previous studies have suggested."

Unrelated mutations, when present in the blood, can lead to false positive results in men with advanced prostate cancer who are undergoing liquid biopsies. Such tests, which look for variants in the cell-free DNA that tumors shed into the blood plasma, help determine suitable treatment options.

"You can actually measure what's happening with a patient's tumor by taking a blood draw," said Dr. Colin Pritchard, associate professor of laboratory medicine and pathology at the University of Washington School of Medicine in Seattle. He also is the associate director of the Genetics and Solid Tumors Laboratory at UW Medicine.

The testing can guide therapy for already-diagnosed cancers by finding mutations that can suggest precision medicine choices. Cell-free DNA testing offers the ease and convenience of testing a blood sample for patients with advanced cancer.

Nonetheless, Pritchard and his team point to the urgency of evaluating the performance of cell-free DNA testing in actual practice and understanding sources of potential interferences with the accuracy of test results.

Two cancer treatment medications, recently approved by the U.S. Food and Drug Administration, or FDA, in fact, are indicated for possible use if certain cell-free DNA mutations appear in the plasma of men whose prostate cancer has spread.

However, other kinds of non-cancer DNA mutations can exit blood cells and get into the plasma.

Pritchard said that precision medicine scientists are learning more about a phenomenon called "clonal hematopoiesis" that can often interfere with cancer liquid biopsy findings. Mutations in some DNA repair genes - BRCA1, BRCA2, and ATM - are associated with male and female cancers.

"Unfortunately, these same genes are also commonly mutated as a result of clonal hematopoiesis," Pritchard said.

He and his research team at UW Medicine and the Brotman Baty Institute for Precision Medicine, a partnership among UW Medicine, Seattle Children's and Fred Hutchinson Cancer Research Center, looked at the degree to which clonal hematopoiesis was confounding prostate cancer liquid biopsy results.

They examined both the prevalence and the gene spectrum of this interference in patients undergoing cell-free DNA testing.

Their research paper appears this week in the Nov. 5 edition of the medical journal, JAMA Oncology.

The researchers discovered that CHIP (clonal hematopoiesis of indeterminant potential) variants accounted for almost half of the somatic DNA repair mutations that the liquid biopsy detected. The presence of these CHIP variants became exponentially more common with advancing age of the patients.

False positives have become an even greater concern as two new classes of PARP inhibitors for prostate cancer became approved in May of 2020 - rucaparib and olaparib. People with a positive liquid biopsy test can be candidates for these drugs. A false positive for these biomarker-guided treatments can lead to misdiagnosis and to patients receiving unnecessary, unhelpful therapy.

About half the time when the plasma is thought to contain a mutation that would guide therapy with these drugs, it actually contains CHIP variants, not prostate cancer DNA variants.

That means that in about half of those tested, a patient could be told that he should be administered a drug that is not indicated to treat to his cancer, Pritchard explained.

Solving this problem of potential misdiagnosis and misguided treatment is fortunately quite simple. Pritchard said that at UW Medicine and at Brotman Baty Institute for Precision Medicine, the laboratory medicine staff examine a sort of paired control: the whole blood cells where the clonal hematopoiesis is and the plasma.

"The good news is that, by looking at the blood cellular compartment, you can tell with pretty good certainty whether something is cancer or something is hematopoiesis," he said.

The research team noted that some of the limitations of their study were the small sample size (69 men), its retrospective approach, and the similarities within their patient population, including the men's prior therapies.

Findings from an international study into the costs and outcomes of informal end of life care have today been published BMC Medicine.

The study found that in the UK, Ireland and the US, care provided by informal carers, meaning family and friends, accounted for more than half of total care costs in the last three months of life.

Researchers concluded that there was an urgent need in all three countries to improve the integration and support for dedicated community palliative care services to improve the care quality and support people across the whole journey of care.

The study surveyed 767 carers in three countries about the last three months of life for the person they cared for. This is the first study of its kind and found:

Costs to informal carers are larger than those to formal care services (health, social and voluntary combined) for people in the last three months of life.

Poor quality home care was associated with greater burden to carers.

If well supported informal carers can play an important role in providing care, and this can be done without detriment to them, providing that they are helped.

Improving community palliative care and informal carer support should be a focus for future investment.

The study was led by researchers from the Cicely Saunders Institute at King's College London in collaboration with King's College Hospital Foundation Trust (UK), Trinity College Dublin (Ireland), Mater Misericordiae Hospital (Ireland), Beaumont Hospital (Ireland), University of Bristol (UK), University of California, San Francisco (USA) and Icahn School of Medicine at Mount Sinai (USA).

The research was funded by Cicely Saunders International, The Atlantic Philanthropies and the National Institute for Health Research Applied Research Collaboration South London.

In the last three months of life, formal care costs are high, but little is known about the costs of informal care and their effects on outcomes. This research is an important contribution to increasing the recognition and understanding of the effort and costs of informal carers, such as families and friends, who do so much. As well as identifying areas where support and investment could help improve care for both the patient and informal and formal carers.

The study Associations between informal care costs, care quality, carer rewards, burden and subsequent grief: the international, access, rights and empowerment mortality follow-back study of the last three months of life (IARE I study) uses the experiences reported by informal carers to determine and compare the informal care costs and their associations with the burden, rewards and subsequent grief, taking the quality of care into account.

The study surveyed 767 carers in London, Dublin, New York and San Francisco. Participants reported the hours and activities of informal care they gave, care quality, the positive aspects and burdens of caregiving, and completed the Texas Revised Inventory of Grief (TRIG).

All costs (formal, informal) were calculated by multiplying reported hours of activities by country specific costs for that activity. Informal care costs used country-specific shadow prices, e.g. average hourly wages, unit costs for nursing care. The study also examined the positive aspects and burdens of caregiving, and the carer's subsequent grief.

Professor Irene Higginson lead of the study said: "Family and friend carers do so much in helping people who need palliative care. Alongside being a wife, husband, partner, daughter, son, friend or other relation, our study shows the huge amount of practical help, advocacy, co-ordination and 'being there' that they provide. This costs more to society that do the formal care services, and when home care is of poor quality the burden on informal carers increases."

Dr Steve Pantilat, from the University of California, San Francisco said: "Family and friends provide tremendous help with the practical and emotional issues that people need as they approach the end of life. We know that this kind of help is priceless and unpaid. We learned that, if paid, the care provided by family and friends would cost more than all the formal care provided by the healthcare system. In addition, caregiving while seen as a privilege for many, also takes its toll on the caregiver. As a society we need to recognise and support these caregivers to keep them healthy and to allow them to continue to care for their loved ones. Palliative care services are among the ways that we can better support caregivers to improve the quality of life for them and the person they are caring for."

Much of what we know regarding how life--as we know it--came into existence is through the recovery of fossils from various sites in the word. The Chengjiang lagerstatte in Yunnan Province, China, is one such unique site containing very well-preserved fossils (also called the "Chengjiang fauna"), which include soft-bodied animals that normally do not get fossilized. Most of these fossils are 520 to 518 million years old, spanning a part of the Cambrian period when life on earth exploded in diversity, leading to a huge increase in number of species--a phenomenon called the "Cambrian explosion." In a new study, two scientists who spent many years digging deeper into this field, including Dr Degan Shu from Northwest University in Xi'an and Dr Jian Han from Northwest University in Shaanxi Xi'an, present an overview of their research on the Chengjiang fauna and emphasize its significance. These findings, which are published in Earth Science Frontiers, include significant contributions from Chinese paleontologists, including Prof Shu's group, in collaboration with other international scientists.

The research spanned three decades, each decade bringing important developments. The first decade (1984-1994) led to important findings on basal animals (e.g., sponges and jellyfish) and the subkingdom Protostomia (e.g., molluscs). In the second decade (1995-2005), scientists including Shu's team continued to discover newer animal groups, the most significant being deuterostomes (a large group of animals, which includes humans). In the third stage (2005-now), the Chinese teams continued to add new groups to the animal tree and dug deeper into the relationships between the formation of the tree and the multi-episodic Cambrian explosion. This paved the way for not only the formulation of a three-part phylogenetic tree of early animals but also the hypothesis that the Cambrian explosion occurred in three episodes--the evolution and diversification of basal animals, followed by protostomes, and finally deuterostomes--forming the basis of all forms of animal life today.

On the importance of the Chengjiang fauna, Dr Shu comments, "Today, many people still believe in creationism, and a common argument that they use is an incomplete fossil record. We feel that filling the gaps in the evolutionary tree with transitional forms, such as those found at Chengjiang and other sites, will help us to gradually dispel misinformation about the theory of evolution, especially when we consider the question of how humans came to be. In essence, we can trace the origins of all extant animals, including us, to ancestors in the Cambrian."

In particular, Dr Shu points to the discovery of seminal fossils that demonstrate the early forms of our basic organs evolved during the Cambrian explosion. These include the mouth, brain, heart, and vertebrae. It is through comparisons of Chengjiang fossils from the Cambrian period with those from the Precambrian (before Cambrian) period that researchers realized that Precambrian life did not have these basic organs. This reveals the importance of Chengjiang as a reservoir of fossilized soft body parts, such as the nervous system. In fact, some specimens have such well-preserved nervous systems that scientists could use them to infer how certain species behaved, working from the idea that a complex nervous system implies complex behaviors. This incredible insight offered to us by the Chengjiang lagerstatte provides direct evidence explaining the gradual evolution in the animal kingdom. Dr Shu concludes, "As a compelling testimony of Darwinian theory, the Chengjiang fossils have profound scientific and humanistic significance. Our hope is that the fascinating discoveries at this site will help improve scientific literacy in the public, while also providing new generations of scientists with a framework that they can use to flesh out the animal tree of life."

The Chengjiang fauna, indeed, holds immense significance--both scientific and philosophical. And the extensive efforts by scientists like Dr Shu bring us closer to understanding the most fundamental question today: where lies the origin of life?

A group of Skoltech scientists developed machine learning (ML) algorithms that can teach artificial intelligence (AI) to determine oil viscosity based on nuclear magnetic resonance (NMR) data. The new method can come in handy for the petroleum industry and other sectors, which have to rely on indirect measurements to characterize a substance. The research was published in the Energy and Fuels journal.

An important parameter of oil and petrochemicals, viscosity has implications for production and processing, while helping to better understand and model the natural processes in the reservoir. Standard oil viscosity assessment and monitoring techniques are very time and money consuming and sometimes technically unfeasible. NMR can help determine the properties thanks to a material's ability to absorb and emit electromagnetic energy. Oil is a chemically heterogeneous mixture of hydrocarbons, which makes the interpretation of NMR results extremely difficult.

A group of scientists from Skoltech, the University of Calgary (Canada), and Curtin University (Australia) processed NMR data using ML algorithms. Their model trained on NMR data on various types of oil from fields in Canada and the United States produced an accurate prediction of viscosity, which was confirmed by lab tests.

According to Dmitry Koroteev, a professor at the Skoltech Center for Hydrocarbon Recovery (CHR) and one of the study leads, their research illustrates how ML algorithms can help characterize materials' properties measured indirectly and, more specifically, by using NMR measurements instead of viscosimetry at the lab. In practical terms, this means that one can obtain information about oil in the subsurface reservoir without extracting samples and taking them to the lab for tests. "Surprisingly, ML works better here than the traditional correlations," comments Professor Koroteev. "The direct and indirect experimental measurements that we had at our disposal were a good training set for our ML algorithms. The tests demonstrated that the algorithms have good generalization ability and do not require retraining."

"What is especially interesting is the high accuracy ML models achieve on extra-heavy oil and bitumen samples. Due to their complex chemical composition, the relationship between NMR relaxation and viscosity is not well defined for these oil types. For the empirical models, the workaround for this is to make additional measurements to determine the relative hydrogen index (RHI) of the oil -- the information which is often not readily available or difficult to measure in the field accurately. Our study shows that by using ML-derived NMR viscosity models, these measurements are not necessary." - explains Skoltech-Curtin Ph.D. student Strahinja Markovic, the first author of the paper.

The scientists are positive that their method can find use beyond the petroleum industry. It is not infrequent that the test sample is unavailable for direct tests, which makes indirect measurements a lucky alternative for a variety of sectors, such as the food industry where the quality of fruit could be tested without even cutting them open, or in agriculture where soil quality assessment could cover much larger areas.