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Despite surgery and subsequent treatment with chemotherapy and radiation, the majority of patients experience recurrence of malignant brain tumours. Researchers at Linköping University, Sweden, and the Medical University of Graz, Austria, have shown in cells in culture that an ion pump can deliver drugs more accurately, which gives less severe adverse effects in chemotherapy. The results have been published in Advanced Materials Technologies.
“This is the first time an ion pump has been tested as a possible method to treat malignant brain tumours. We used cancer cells in the lab, and the results are extremely promising. However, it will probably take five to ten years before we see this new technology used in treatments for brain tumours,” says Daniel Simon, associate professor at the Laboratory of Organic Electronics at the Department of Science and Technology at Linköping University .
The scientists have used cells from glioblastoma, which is the most common and most aggressive type of cancer that can arise in the brain. When a brain tumour is surgically removed, small parts of the tumour are often left behind, embedded between the brain cells. Even high-precision surgery cannot remove these cells without damaging the surrounding healthy brain tissue. This means that radiation treatment and chemotherapy are used to stop the recurrence of the tumour.
In Sweden, around 30 cytostatics are available to treat different types of cancer. These chemotherapy agents are most often given either intravenously or as a tablet. But in order to reach the brain, they must first spread through the circulatory system and then pass through the blood-brain barrier. The walls of the small blood vessels in the brain are much less permeable than blood vessels in the rest of the body, and can prevent many substances in the blood entering the brain. Thus, only a few drugs that work against cancer can pass through.
Scientists at Linköping University and at the Medical University of Graz have now developed a method in which an implanted ion pump can be used to get around the blood-brain barrier and supply gemcitabine — an extremely effective chemotherapy agent that cannot normally pass the blood-brain barrier — directly into the brain with high precision. Gemcitabine is currently used to treat cancers in the pancreas, bladder and breast, where it acts by disrupting the cell division process in rapidly growing tumours. This means that gemcitabine does not affect brain cells, since these do not, in general, undergo cell division.
“The traditional glioblastoma treatment currently used in the clinics harms both cancer and neuronal cells to the same extent. However, with the gemcitabine ion pump, we tackle only the cancerous cells, while neurons stay healthy. In addition, our experiments on cultured glioblastoma cells show that more cancer cells are killed when we use the ion pump than when we use manual treatment,” says Linda Waldherr, postdoctoral fellow at the Medical University of Graz. She has conducted the study together with researchers at Linköping University.
When the ion pump is to transport gemcitabine from an electrolyte reservoir into cells or a tumour, a low current is used to “pump” the positively charged drug through an ion transport channel. The method is known as electrophoresis. The ion pump needs only a low current to pump the gemcitabine, which is an advantage since it avoids the risk that brain cells are activated and transmit unintended nerve signals. The low current and voltage also mean that eventual therapeutic technology will not require large power supplies or batteries to operate.
Rainer Schindl, associate professor at the Medical University of Graz, describes other advantages.
“The pressure inside the brain is extremely sensitive, and using an ion pump to transport the drug instead of a fluid-driven device means that the pressure is not affected. Also, the dosage is controlled by electrical charging, which makes the supply of the chemotherapy agent extremely precise. The next step will be to use the ion pump to evaluate different chemotherapy agents that have previously given adverse effects that are too serious or that are unable to pass the blood-brain barrier,” he says.
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Materials provided by Linköping University. Original written by Anders Ryttarson Törneholm. Note: Content may be edited for style and length.

Clusters of a virus known to cause stomach flu are resistant to detergent and ultraviolet disinfection, according to new research co-led by Danmeng Shuai, Ph.D., an associate professor of civil and environmental engineering at the George Washington University and Nihal Altan-Bonnet, Ph.D., a senior investigator and the head of the Laboratory of Host-Pathogen Dynamics at the National Heart, Lung, and Blood Institute, part of the National Institutes of Health. The findings suggest the need to revisit current disinfection, sanitation and hygiene practices aimed at protecting people from noroviruses.
Noroviruses are the leading cause of gastroenteritis around the world, with over 21 million cases each year in the United States alone.
In 2018, Altan-Bonnet’s team found that noroviruses can be transmitted to humans via membrane-enclosed packets that contain more than one virus. In the past, scientists thought that viruses spread through exposure to individual virus particles, but the 2018 study — and others — showed how membrane-enclosed clusters arrive at a human cell and release an army of viruses all at once.
For the new study, Shuai, Altan-Bonnet and the study’s first author Mengyang Zhang, a doctoral student co-advised through a GW/NIH Graduate Partnerships Program, looked at the behavior of these protected virus clusters in the environment. They found that the virus clusters could survive attempts to disinfect with detergent solutions or even UV light. Water treatment plants use UV light to kill noroviruses and other pathogens.
“These membrane-cloaked viruses are tricky,” Shuai said. “Past research shows they can evade the body’s immune system and that they are highly infectious. Our study shows these membrane enclosed viruses are also able to dodge efforts to kill them with standard disinfectants.”
According to the researchers, future studies must be done to find out if certain kinds of cleaning solutions or higher dosages of UV light would degrade the protective membrane and/or kill the viruses inside. Ultimately, the research could be used to devise more effective disinfection methods that could be used to clean surfaces at home, in restaurants and in places where norovirus can spread and cause outbreaks, like cruise ships.
“Our study’s findings represent a step towards providing rigorous guidelines for pathogen control, particularly in our built environment, and public health protection,” Altan-Bonnet said.
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Materials provided by George Washington University. Note: Content may be edited for style and length.

Maintenance of good oral health is more important than use of antibiotics in dental procedures for some heart patients to prevent a heart infection caused by bacteria around the teeth, according to a new American Heart Association (AHA) scientific statement published today in the association’s flagship journal, Circulation.
Infective endocarditis (IE), also called bacterial endocarditis, is a heart infection caused by bacteria that enter the bloodstream and settle in the heart lining, a heart valve or a blood vessel. It is uncommon, but people with heart valve disease or previous valve surgery, congenital heart disease or recurrent infective endocarditis have a greater risk of complications if they develop IE. Intravenous drug use also increases risk for IE. Viridans group streptococcal infective endocarditis (VGS IE) is caused by bacteria that collect in plaque on the tooth surface and cause inflammation and swelling of the gums. There’s been concern that certain dental procedures may increase the risk of developing VGS IE in vulnerable patients.
The new guidance affirms previous recommendations that only four categories of heart patients should be prescribed antibiotics prior to certain dental procedures to prevent VGS IE due to their higher risk for complications from the infection:those with prosthetic heart valves or prosthetic material used for valve repair; those who have had a previous case of infective endocarditis; adults and children with congenital heart disease; or people who have undergone a heart transplant.

Approximately one in four patients hospitalized for the acute respiratory distress syndrome (ARDS) associated with severe COVID-19 infections may have a distinct phenotype (disease presentation) or biochemical profile associated with organ dysfunction, blood-clotting abnormalities and greater risk of death than patients with other, seemingly similar forms of the disease, researchers at Massachusetts General Hospital (MGH) have found.
Among 263 patients admitted to intensive care units (ICUs) at MGH for respiratory failure due to severe COVID-19 infection, 70 (26.6%) had increased levels of biomarkers in the bloodstream indicating disordered blood clotting, higher inflammation, and organ dysfunction compared with the other patients, report Sylvia Ranjeva MD, PhD, and Lorenzo Berra, MD, investigators in the Department of Anesthesia, Critical Care and Pain Medicine, and their colleagues in that department and Pulmonary and Critical Care Medicine and Respiratory Care at MGH.
Patients with this more severe phenotype had twice the risk of death, despite minimal differences in respiratory mechanics or in the severity of ARDS between the two phenotypes.
Their findings are published in EClinicalMedicine, an open-access journal of The Lancet group.
ARDS is a catch-all term for lung injury that can arise from many different conditions such as pneumonia, severe influenza, trauma, blood infections or inflammation of the pancreas.
The syndrome can be life-threatening and may require patients to be put on mechanical ventilation, but it has been difficult for clinicians to develop effective therapies because of the wide spectrum of causes associated with it.

Young adults must step up their exercise routines to reduce their chances of developing high blood pressure or hypertension — a condition that may lead to heart attack and stroke, as well as dementia in later life.
Current guidelines indicate that adults should have a minimum of two-and-a-half hours of moderate intensity exercise each week, but a new study led by UCSF Benioff Children’s Hospitals reveals that boosting exercise to as much as five hours a week may protect against hypertension in midlife — particularly if it is sustained in one’s thirties, forties and fifties.
In the study publishing in American Journal of Preventive Medicine on April 15, researchers followed approximately 5,000 adults ages 18 to 30 for 30 years. The participants were asked about their exercise habits, medical history, smoking status and alcohol use. Blood pressure and weight were monitored, together with cholesterol and triglycerides.
Hypertension was noted if blood pressure was 130 over 80 mmHg, the threshold established in 2017 by the American College of Cardiology/American Heart Association.
The 5,115 participants had been enrolled by the Coronary Artery Risk Development in Young Adults (CARDIA) study and came from urban sites in Birmingham, Ala., Chicago, Minneapolis and Oakland, Calif. Approximately half the participants were Black (51.6 percent) and the remainder were White. Just under half (45.5 percent) were men.
Fitness Levels Fall Fast for Black Men Leading to More Hypertension
Among the four groups, who were categorized by race and gender, Black men were found to be the most active in early adulthood, exercising slightly more than White men and significantly more than Black women and White women. But by the time Black men reached age 60, exercise intake had slumped from a peak of approximately 560 exercise units to around 300 units, the equivalent to the minimum of two-and-a-half hours a week of moderate intensity exercise recommended by the U.S. Department of Health and Human Services. This was substantially less exercise than White men (approximately 430 units) and slightly more than White women (approximately 320 units). Of the four groups, Black women had the least exercise throughout the study period and saw declines over time to approximately 200 units.

An observational study in nearly 20,000 individuals has found that greater intake of red and processed meat is associated with worse heart function. The research is presented at ESC Preventive Cardiology 2021, an online scientific congress of the European Society of Cardiology (ESC).
“Previous studies have shown links between greater red meat consumption and increased risk of heart attacks or dying from heart disease,” said study author Dr. Zahra Raisi-Estabragh of Queen Mary University of London, UK. “For the first time, we examined the relationships between meat consumption and imaging measures of heart health. This may help us to understand the mechanisms underlying the previously observed connections with cardiovascular disease.”
The study included 19,408 participants of the UK Biobank. The researchers examined associations of self-reported intake of red and processed meat with heart anatomy and function.
Three types of heart measures were analysed. First, cardiovascular magnetic resonance (CMR) assessments of heart function used in clinical practice such as volume of the ventricles and measures of the pumping function of the ventricles. Second, novel CMR radiomics used in research to extract detailed information from heart images such as shape and texture (which indicates health of the heart muscle). Third, elasticity of the blood vessels (stretchy arteries are healthier).
The analysis was adjusted for other factors that might influence the relationship including age, sex, deprivation, education, smoking, alcohol, exercise, high blood pressure, high cholesterol, diabetes, and body mass index (BMI) as a measure of obesity.
The researchers found that greater intake of red and processed meat was associated with worse imaging measures of heart health, across all measures studied. Specifically, individuals with higher meat intake had smaller ventricles, poorer heart function, and stiffer arteries — all markers of worse cardiovascular health.
As a comparison, the researchers also tested the relationships between heart imaging measures and intake of oily fish, which has previously been linked with better heart health. They found that as the amount of oily fish consumption rose, heart function improved, and arteries were stretchier.
Dr. Raisi-Estabragh said: “The findings support prior observations linking red and processed meat consumption with heart disease and provide unique insights into links with heart and vascular structure and function.”
The associations between imaging measures of heart health and meat intake were only partially explained by high blood pressure, high cholesterol, diabetes, and obesity.
“It has been suggested that these factors could be the reason for the observed relationship between meat and heart disease,” said Dr. Raisi-Estabragh. “For example, it is possible that greater red meat intake leads to raised blood cholesterol and this in turn causes heart disease. Our study suggests that these four factors do play a role in the links between meat intake and heart health, but they are not the full story.”
She noted that the study did not look into alternative mechanisms. But she said: “There is some evidence that red meat alters the gut microbiome, leading to higher levels of certain metabolites in the blood, which have in turn been linked to greater risk of heart disease.”
Dr. Raisi-Estabragh said: “This was an observational study and causation cannot be assumed. But in general, it seems sensible to limit intake of red and processed meat for heart health reasons.”
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Materials provided by European Society of Cardiology. Note: Content may be edited for style and length.

Researchers at the University of Zurich show that increased sensitivity in a specific region of the brain contributes to the development of anxiety and depression in response to real-life stress. Their study establishes an objective neurobiological measure for stress resilience in humans.
Some people don’t seem to be too bothered when it comes to handling stress. For others, however, prolonged exposure to stress can lead to symptoms of anxiety and depression. While stress resilience is a widely discussed concept, it is still very challenging to predict people’s individual response to increased levels of stress. Lab experiments can only go so far in replicating the chronic stress many people experience in their day-to-day lives, as stress simulated in the lab is always limited in exposure time and intensity.
It is possible, however, to observe a group of medical students who are all about to face real-life stress for an extended period — during their six-month internship in the emergency room. This is precisely the real-life situation on which a team of researchers involving Marcus Grueschow and Christian Ruff from the UZH Zurich Center for Neuroeconomics and Birgit Kleim from the Department of Psychology and the University Hospital of Psychiatry Zurich based their study.
Stress as a response to cognitive conflict and loss of control
Before starting their internship, the subjects were given a task that required them to process conflicting information. This conflict task activates the locus coeruleus-norepinephrine (LC-NE) system, a region of the brain associated with regulating our response to stress and resolving conflict. However, the intensity of LC-NE activation — often referred to as the “firing rate” — varies from one person to the next.
Subjects with a higher LC-NE responsivity showed more symptoms of anxiety and depression following their emergency room internships. “The more responsive the LC-NE system, the more likely a person will develop symptoms of anxiety and depression when they’re exposed to prolonged stress,” Marcus Grueschow summarizes their findings.
Objective measure predicting stress resilience
With their study, the scientists have identified an objective neurobiological measure that can predict a person’s stress response. This is the first demonstration that in humans, differences in LC-NE responsivity can be used as an indicator for stress resilience. “Having an objective measure of a person’s ability to cope with stress can be very helpful, for example when it comes to choosing a profession. Or it could be applied in stress resilience training with neuro-feedback,” Marcus Grueschow explains.
This does not mean that aspiring doctors or future police officers will all have to have their brain scanned. “There might be an even more accessible indicator for stress resilience,” Christian Ruff says. Research with animals suggests that stimulation of the LC-NE system correlates with pupil dilation. “If we could establish the same causal link between pupil dilation and the LC-NE system in humans, it would open up another avenue,” he adds.
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Materials provided by University of Zurich. Note: Content may be edited for style and length.

Despite dire predictions, the number of suicides fell by 5 percent over all. Still, smaller studies suggested the trends were much worse among nonwhite Americans.Ever since the pandemic started, mental health experts have worried that grief, financial strain and social isolation may take an unbearable toll on American psyches. Some warned that the coronavirus had created the “perfect storm” for a rise in suicides.The concern was seized on by lawmakers who were eager to reopen the economy. In March 2020, Donald J. Trump predicted a surge in suicides resulting from statewide lockdowns. A provisional tally of last year’s deaths, however, contains a surprising nugget of good news.While nearly 350,000 Americans died from Covid-19, the number of suicides dropped by 5 percent, to 44,834 deaths in 2020 from 47,511 in 2019. It is the second year in a row that the number has fallen, after cresting in 2018.The decline came even as the number of unintentional overdose deaths rose dramatically during the pandemic. Some overdoses are classified as suicides; there is debate among researchers as to how many ought to be included.But while the number of suicides may have declined over all, preliminary studies of local communities in states like Illinois, Maryland and Connecticut found a rise in suicides among Black Americans and other people of color when compared with previous years.Whether that is the case nationally is not known. Federal health officials have yet to release a detailed breakdown of the race and ethnicity of last year’s suicide victims, and some experts have cautioned against making generalizations based on trends in a few localities.“We can’t make any bold statements until we have more national data,” said Arielle Sheftall, a principal investigator at the Center for Suicide Prevention and Research at Nationwide Children’s Hospital in Columbus, Ohio. “It may be that only certain areas or certain cities have experienced these increases” among people of color, she added.Suicides are comparatively rare events, and it is hard to know how to interpret changes in small numbers and whether they represent statistical hiccups or broad trends. Rates usually fall off during times of war or natural disasters, when people feel drawn together to fight for survival against a common enemy. But the effect can peter out over time, and fatigue and despair may follow, experts say.In the early days of the pandemic, families posted colorful drawings of rainbows in their windows and children stuck their heads out each day at 7 p.m. to ring bells and cheer for health care workers.“During the early phase of a natural disaster, there’s a sense of community building, a feeling that we’re all in this together,” said Dr. Christine Moutier, chief medical officer for the American Foundation for Suicide Prevention. “The survival instinct can really kick in front and center.”The initial sense of crisis and purpose may have been a source of strength for people around the world. A new study of suicide trends among residents of 10 countries and 11 states or regions with higher incomes found that the number remained largely unchanged or had even declined during the early months of the pandemic, though there were increases in suicide later in the year in some areas. (Another study that has not yet been peer reviewed reported sharp increases in suicide from July to November in Japan, with a greater increase in suicides among women during that time period.)In the United States, the pandemic has taken a starkly disproportionate toll on communities of color: Hispanic, Black and Native Americans, as well as Alaska Natives, are more likely than white Americans to be hospitalized with Covid-19 and to die from it. Two in five Black and Hispanic Americans have lost a close friend or family member to the virus, compared with one in four white adults.People of color have also been pummeled financially, particularly low-wage earners who have lost their jobs and had few resources on which to fall back. Many who remain employed hold jobs that put them at risk of contracting the virus on a daily basis.Anxiety and depression have risen across the board, and many Americans are consumed with worry about their health and that of their families. A recent study found that one in 12 adults has had thoughts of suicide; Hispanic Americans in particular said they were depressed and stressed about keeping a roof over their heads and having enough food to eat.Some Americans plunged into poverty for the first time, shattering their sense of identity and self, said Dr. Brandi Jackson, a psychiatrist who is director of integrative behavioral health at Howard Brown Health in Chicago.News reports about the killings of Black people, from Breonna Taylor and Ahmaud Arbery to the shocking death of George Floyd in May, added to the trauma for Black Americans, Dr. Jackson said.“It’s one stressor on top of another stressor on top of another stressor,” Dr. Sheftall said. “You’ve lost your job. You’ve lost people in your family. Then there’s George Floyd. At one point, I had to shut the TV off.”A makeshift memorial for George Floyd at the Cup Foods in Minneapolis last week.Joshua Rashaad McFadden for The New York TimesResearchers who study the racial trends said increases in suicide among people of color were consistent across the cities and regions that they examined — and all the more striking because suicide rates among Black and Hispanic Americans had always been comparatively low, about one-third the rate among white Americans.Rodney Moore Sr., of Anaheim, Calif., lost his 14-year-old son, Rodney Jr., to suicide in January. Mr. Moore believes that his son despaired when his school did not reopen as expected earlier this year.Mr. Moore urged parents to be on the lookout for any changes in behavior or mood in their children that could indicate hopelessness about the future. “Look out for anything that is different in their sleeping, their eating, a change in attitudes, a personality change,” he said.Public health officials in Chicago were among the first to notice that even though overall suicide numbers remained stable during the first eight months of 2020, the number of suicides among Black residents had increased.Officials were particularly concerned about a rise in suicides among young Black adults in their 20s, as well as by an increase among older people of all races, issuing a health alert in November and taking steps to beef up funding for crisis hotlines and mental health services.The state’s Department of Health in January reported a similarly lopsided trend, saying suicides in the state had dropped by 6.8 percent over all, but they had risen by 27.7 percent among Black residents and by 6 percent among Hispanic individuals.“It’s important to not just be monitoring the topline numbers, because we know that Covid has impacted different communities in disparate ways,” said Matthew Richards, the deputy commissioner for behavior health at Chicago Department of Public Health.“When we talk about Covid and the amount of trauma, grief and stress at the community level — we should not underestimate how significant a public health issue that has the potential to be.”A similar trend appeared in Maryland, where researchers analyzed suicide deaths from March 5, 2020, when a statewide emergency was declared, to May 7, when public spaces started to reopen, and then compared them with the same periods during previous years.The study found that suicides fell by almost half among white Americans — but doubled among Black residents of the state after the emergency declaration in March. (There was no change in suicide trends from Jan. 1 to March 4 of last year.)“It’s clear the pandemic has hit African-Americans a lot harder than it has whites,” said Dr. Paul Nestadt, an assistant professor of psychiatry and behavioral sciences at Johns Hopkins who was the senior author of the study, which was published in JAMA Psychiatry in December.“The pandemic may have been a perfect storm, but we’ve all been in very different boats in that storm,” he added.He and a colleague, Michael Bray, have continued to investigate and say there is preliminary evidence that suicide rates have also increased among Hispanics in Maryland last year.In Connecticut, Yale University scientists who studied death rates during the period of strict stay-at-home measures in that state, between March 10 and May 20 of last year, were also at first surprised to find that the overall suicide rate in the state had plummeted by 20 percent, when compared with the same period in 2019.But a closer look revealed that while suicide among white residents had plunged to a six-year low, the rate among the nonwhite population had risen.Of 74 Connecticut residents who died by suicide during the lockdown period, 23 percent identified as nonwhite, nearly double the percentage of suicide deaths compared with the previous six years, the researchers found. Neither the average age of suicide death (50) nor the sex ratio (three-quarters were men) had changed.“It was deeply disturbing,” said Dr. Thomas O. Mitchell, a psychiatrist and one of the authors of the paper, which was published in the journal Psychiatry Research in December. He said that financial strain — known to be strongly linked to suicide — might have played a critical role in the deaths.“People in minority groups already face unique economic challenges, so the financial crisis from losing a job during the pandemic might be felt even more intensely by these communities,” Dr. Mitchell said, adding that those who continued to work in public-facing jobs “are putting their life on the line every day — a stressful thing to do.”Jasmin Pierre, a Black woman is now a mental health advocate, narrowly survived a suicide attempt seven years ago after a number of setbacks, including a job loss and the death of her sister.Many friends and relatives responded with disbelief. “They said, ‘Black people don’t do that,’ or, ‘Girl, go and pray,’” recalled Ms. Pierre, who has developed an educational app called The Safe Place. “But actually, we do do that. We just don’t talk about it. It’s taboo.”If you are having thoughts of suicide, call the National Suicide Prevention Lifeline at 1-800-273-8255 (TALK). You can find a list of additional resources at SpeakingOfSuicide.com/resources.

Any future attempts to reduce the spread of covid-19 should be focused on tackling close airborne transmission of the virus which is considered to be the primary route for its circulation, according to experts in an editorial published in The BMJ.
Respiratory experts argue that it is now clear that covid-19 (SARS-CoV-2) is most likely to transmit between people at close range through inhalation rather than through contact with surfaces or longer range airborne routes, although those routes can also be responsible.
The covid-19 pandemic has helped to redefine airborne transmission of viruses, say the experts from the universities of Leicester, Edinburgh Napier and Hong Kong, Virginia Tech, and NHS Lanarkshire, Edinburgh.
There has been some confusion over precise definitions of air transmissions of infections from the last century in which the difference between “droplet” “airborne,” and “droplet nuclei” transmission have led to misunderstandings over the physical behaviour of these particles, they say.
What is important to know, they claim, is that if a person can inhale particles, regardless of their size or name, they are breathing in aerosols. And while this can happen at long range, it is more likely to happen when being close to someone because the aerosols between two people are much more concentrated at short range, similar to being close to someone who is smoking.
People infected with SARS-CoV-2 produce many small respiratory particles full of the virus as they exhale. Some of these will be inhaled almost immediately by those within a typical conversational “short range” distance of less than one metre, say the experts, while the remainder will disperse over longer distances to be inhaled by others further away — more than two metres.