Publisher Health

Malaria, a disease caused mainly by the parasites Plasmodium falciparum and Plasmodium vivax, (P. vivax) is associated with over 400,000 deaths each year. Previously, the spleen was assumed to mostly play a role in parasite destruction, as it eliminates malaria parasites after antimalarial treatment. A study published in the open access journal PLOS Medicine by Steven Kho and Nicholas Anstey at Menzies School of Health Research, Australia, and international colleagues, suggests that in chronic P. vivax infections, malaria parasites survive and replicate via a previously undetected lifecycle within the spleen.

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A clinical trial examining the efficacy of two devices to monitor and detect atrial fibrillation (AF), or an irregular heartbeat, in ischemic stroke patients — one an implantable device that monitors over 12 months, the other an external device that monitors over a 30-day period — found the implantable device is more than three times more effective in detecting AF, and both are a significant improvement over the current standard of care in Alberta, Canada.
The Post-Embolic Rhythm Detection With Implantable Versus External Monitoring (PER DIEM) study, led jointly by University of Alberta and University of Calgary researchers, was published today in the journal JAMA. The findings are expected to significantly change practice in how clinicians look for AF in Albertan patients following ischemic stroke.
“We know that (the current method of monitoring) isn’t as effective as it could be in picking up atrial fibrillation from this study because regardless of which arm of the study patients went into, we were picking up anywhere from five to 15 per cent extra atrial fibrillation,” said Brian Buck, a stroke neurologist and associate professor of medicine at the U of A. “We found in the study there were a lot of patients with undetected atrial fibrillation, even after they received the standard cardiac monitoring.”
Atrial fibrillation causes about one in four strokes in Alberta. Detecting it early is key to preventing further disabling strokes in patients who have already experienced ischemic stroke, a type of stroke caused by a blockage in an artery that supplies blood to the brain. If atrial fibrillation is detected, clinicians have treatments — mainly blood thinners — that can reduce the risk of stroke by almost 70 per cent.
The standard test in Alberta for AF is a 24-hour electrocardiogram monitor. In the PER DIEM trial, 300 Albertan patients who had suffered a stroke were randomized to one of two new devices that can monitor for AF for longer durations. The study showed that the implantable device picked up three times more new AF than the 30-day monitor (15 per cent versus five per cent). All of the patients in the clinical trial with new AF were started on blood thinners.
“We didn’t expect that we would get such a dramatic increase with the longer recording, even though it intuitively makes sense,” said study co-author Michael Hill, professor of neurology at the University of Calgary and senior medical director for stroke with Alberta Health Services’ Cardiovascular and Stroke Strategic Clinical Network. “Most people suspected that detection rates apply to only certain subtypes of ischemic stroke. This study showed that theory is not correct.”
“We believe that those patients that were identified with atrial fibrillation are now, for the rest of their lives, going to have a much lower risk of having a stroke in the future,” added Buck, who is also a member of the U of A’s Neuroscience and Mental Health Institute.

Aerosol reductions that would take place as countries meet climate goals could contribute to global cooling and prevent more than one million annual premature deaths over a decade, according to a new study from the University of California San Diego.
The landmark Paris Agreement of 2016 does not address emissions of aerosols — fine particulates like soot that cause pollution. Nonetheless, findings from the recent study authored by researchers at UC San Diego’s Scripps Institution of Oceanography and the School of Global Policy and Strategy suggests that aerosol accounting should be explicitly incorporated into international climate policy.
It is crucial because as countries implement their greenhouse gas reduction targets under the Paris climate agreement, their choices about which sectors to target will also reduce aerosols that are co-emitted, which will have major impacts to public health and global temperatures.
“Joint consideration of greenhouse gases and aerosols is critical,” said Pascal Polonik, a Ph.D. student at Scripps Oceanography and first author of the paper published in Earth’s Future. “Polluting particles, known as aerosols, are emitted in tandem with greenhouse gases but aren’t accounted for. While all greenhouse gas emissions might be thought of as unambiguously harmful, aerosols are more complicated. All aerosols are harmful to human health but they also often help counteract global warming by cooling the Earth’s surface.”
It is estimated that emissions of aerosols from burning fossil fuels like coal and diesel are responsible for nine million premature deaths worldwide. Though most aerosols have a cooling effect because they reflect sunlight, certain types, such as black carbon have a warming effect.
The UC San Diego team wanted to explore the tradeoffs countries would face by taking aerosols into consideration while concurrently making CO2 cuts to implement Paris pledges.

Dr. Howard Bauchner will leave his post after a colleague suggested “taking racism out of the conversation” on a journal podcast.Following an outcry over comments about racism made by an editor at JAMA, the influential medical journal, the top editor, Dr. Howard Bauchner, will step down from his post effective June 30.The move was announced on Tuesday by the American Medical Association, which oversees the journal. Dr. Bauchner, who had led JAMA since 2011, had been on administrative leave since March because of an ongoing investigation into comments made on the journal’s podcast.Dr. Edward Livingston, another editor at JAMA, had claimed that socioeconomic factors, not structural racism, held back communities of color. A tweet promoting the podcast had said that no physician could be racist. It was later deleted.“I remain profoundly disappointed in myself for the lapses that led to the publishing of the tweet and podcast,” Dr. Bauchner said in a statement. “Although I did not write or even see the tweet, or create the podcast, as editor in chief, I am ultimately responsible for them.”Last month, the A.M.A.’s leaders admitted to serious missteps and proposed a three-year plan to “dismantle structural racism” within the organization and in medicine. The announcement on Tuesday did not mention the status of the investigation at JAMA. The journal declined further comment.“This is a real moment for JAMA and the A.M.A. to recreate themselves from a founding history that was based in segregation and racism to one that is now based on racial equity,” said Dr. Stella Safo, a Black primary care physician at the Icahn School of Medicine at Mount Sinai in New York.Dr. Safo and her colleagues started a petition, now signed by more than 9,000 people, that had called on JAMA to restructure its staff and hold a series of town hall conversations about racism in medicine. “I think that this is a step in the right direction,” she said of the announcement.But other critics said they were withholding judgment to see how the organization addressed what they saw as pervasive neglect of covering racism’s impact on health in its journals.“In the entire history of all the JAMA network journals, there’s only been one non-white editor,” noted Dr. Raymond Givens, a cardiologist at Columbia University in New York. In October, Dr. Givens wrote to Dr. Bauchner, noting that editors at the JAMA journals were overwhelmingly white and male. Dr. Bauchner did not respond, according to Dr. Givens.“This is not cause to celebrate,” he said of the announcement, adding that he had not intended to jeopardize Dr. Bauchner’s job. Nor will appointing a top editor of color resolve the issues, Dr. Givens said.“Looking for just a person of color misses the point,” he added. “I’m more interested in a bold voice. I want somebody who is willing to take a stand, push to move things forward.”The podcast that set the events in motion aired on Feb. 24 and did not include any Black researchers or experts on racism in medicine.“Structural racism is an unfortunate term,” Dr. Livingston, who is white, said on the podcast. “Personally, I think taking racism out of the conversation will help. Many people like myself are offended by the implication that we are somehow racist.”The podcast was promoted with a tweet from the journal that said, “No physician is racist, so how can there be structural racism in health care?” Following widespread protest in the medical community, the journal took down the podcast and deleted the tweet.“Comments made in the podcast were inaccurate, offensive, hurtful and inconsistent with the standards of JAMA,” Dr. Bauchner said in a statement released a week later. “We are instituting changes that will address and prevent such failures from happening again.”Dr. Livingston later resigned, and the A.M.A. placed Dr. Bauchner on administrative leave on March 25.The JAMA family of journals added four new titles under Dr. Bauchner’s leadership, and expanded to include podcasts, videos and new, shorter article types. But critics noted that the journals rarely addressed structural racism in medicine, and more often published papers linking health disparities to socioeconomic or biological factors.Dr. Bauchner’s exit offered the journals a chance to improve, said Dr. Mary Bassett, professor of the practice of health and human rights at Harvard University.“Medical journals have helped build the racist idea that races have intrinsic differences that have a bearing on health,” Dr. Bassett said. Journals are “challenged to embrace, not only accept, racism as a health issue.”Dr. Bauchner told The New York Times last month that JAMA had published “more than 100 articles on issues such as social determinants of health, health care disparities and structural racism over just the last five years.” He also noted that JAMA accepted only a tiny fraction of the manuscripts it had received.He said in the statement on Tuesday that the journal would be better served by his resignation. “The best path forward for the JAMA Network, and for me personally, is to create an opportunity for new leadership at JAMA,” he said.In an editorial published in JAMA on Tuesday, colleagues at the journal lauded Dr. Bauchner’s leadership, saying he “has left an indelible legacy of progress, innovation and excellence in medical journalism.”The A.M.A. said it has begun a search for Dr. Bauchner’s replacement. The journal’s executive editor, Dr. Phil Fontanarosa, will serve as interim editor in chief.Whoever the new editor may be, he or she will need to acknowledge the profound impact of structural racism on health outcomes for communities of color, Dr. Bassett said.“Racism works in ways that are structural and not simply as the result of ignorant, misguided or even racist individuals,” she added. “As a new editor in chief is sought, there will be a chance for JAMA to lead in dismantling this idea. I hope they grab it.”

University of Queensland scientists working to unlock the mysteries Australia’s deadly stonefish have made a discovery which could change how sting victims are treated in the future.
Stonefish are the most venomous fish in world and are found throughout shallow coastal waters of the northern half of Australia.
Study co-author Associate Professor Bryan Fry said previous studies have not been able to uncover all of the mechanisms at play in stonefish venom because of the way the venom was tested.
“There’s a couple of reasons previous studies haven’t been able to thoroughly decipher the toxicological mysteries of stonefish venom,” Dr Fry said.
“But we’ve discovered a big one — labs were previously analysing only freeze-dried venom, as the venom is often dried in order to make it more stable for transportation and storage.
“By testing freshly milked venom our analysis revealed that the process of freeze-drying destroys paralytic neurotoxic activity of the sample, a key activity we’re observing.

Using a brain-training app helps people eat less junk food and lose weight, new research suggests.
The Food Trainer (FoodT app) trains people to tap on images of healthy foods — but to stop when they see unhealthy snacks, creating an association between these foods and stopping.
The new study, by the universities of Exeter and Helsinki, found that playing the game about once a day for a month led to an average one-point reduction of junk food consumption on an eight-point scale (the scale ranges from four or more items per day, to one or zero items per month).
Overall, people who used the app more also reported larger changes in their food intake.
About half of the study’s 1,234 participants followed the recommendation and played the game at least 10 times.
Across all participants, an average weight loss of half a kilogram (just over a pound) and a small increase in healthy food eaten was seen.

Researchers at Columbia University Mailman School of Public Health and Universidade Federal de Ciências da Saúde de Porto Alegre, Brazil found that when health workers were trained to promote infant healthy feeding practices to pregnant women their children consumed less fats and carbohydrates at 3 years of age and had lower measures of body fat at the age of 6. The study is the first to show that the roots for obesity start in the first year of life, after mothers stop breastfeeding. The findings are published online in the Journal of Human Nutrition and Dietetics.
“The first year after birth is a critical window for the establishment of habits that will influence health patterns throughout one’s lifetime, said Caroline N. Sangalli, in the Graduate Program in Health Sciences, Universidade Federal de Ciências da Saúde de Porto Alegre, Brazil, and first author. “The message worldwide is that to avoid obesity later in life you cannot start too early to help mothers feed their children well. And this study is proof of principle that it is possible to change a mother’s behavior.”
“Most surprising was that the mothers in our randomized trial offered ultra-processed foods, that are high in sugar and fat, as early as 6 months of age,” said Ma?rcia Vitolo, Graduate Program in Pediatrics: Child and Adolescent Health Care, Universidade Federal de Ciências da Saúde de Porto Alegre, Brazil, and co-senior author. “This behavior can be explained by cultural influences and strong marketing of processed baby foods which continues globally.”
The researchers conducted the randomized trial in Porto Alegre, Brazil, in 31 centers that provide prenatal, infant, and other primary care services to low-income families. The intervention was based on births from May 2008 to February 2009 and consisted of a training program to increase the knowledge of primary healthcare workers centered on the ‘Ten Steps for Healthy Feeding for Brazilian Children from Birth to Two Years of Age’, the Brazilian dietary guideline.
All families were informed about complementary foods that should not be offered to children under 2 years of age (i.e., cookies, snacks, soft drinks and sweets) through posters in waiting rooms. Trained interviewers measured children’s growth and other outcomes at ages 6 months, 12 months, 3 years and 6 years at subsequent home visits. Details about food types, amounts and preparation methods were also recorded.
Energy intake at all ages was lower in the intervention group compared to the control group with a statistically significant difference at age 3 years. Also, children from the intervention group at 3 years of age had lower consumption of carbohydrates and total fat than the control group and at 6 years of age had accumulated less body fat as measured by a smaller waist circumference and thinner skinfolds. “We found that the energy intake in both study groups was above the requirement across all age waves; however, the excess energy intake was less in the intervention group,” observed Sangalli, who analyzed the study results with Dr. L.H. Lumey at Columbia Mailman School of Public Health with a grant from the Brazil government. “Although the disparity was slight at the onset, in the long term, the reduced intake of 92 kcal per day adds up to 33,000 kcal per year, and changes of this magnitude could explain changes in weight gain during childhood.”
The findings were particularly striking with regard to calories from cookies and powder chocolate, important sources of carbohydrates and fats. During the health workers training, sugar, sweets, soft drinks, salty snacks, cookies and ultra-processed foods were emphasized as foods for mothers to avoid for their babies until 2 years of age.
The intervention group at 6 years of age had lower body fat on several measures but this difference was not reflected in BMI-scores, a less sensitive measure of adiposity. “However with the prevalence of overweight in the intervention group at 7 percent lower than the control group at 6 years, this does suggest a valuable public health impact — especially since estimates indicate that the reduction in 1 percent of obesity prevalence among children up to age 6 years would save $1.7 billion in medical costs,” said Vitolo.
“Many individuals including Alice Waters, Jamie Oliver, and Michelle Obama have devoted efforts to improve school lunches and eating habits of school age children to aid in the fight against obesity,” said Dr. Lumey, professor of Epidemiology and a co-senior author. “All these efforts are to be applauded and encouraged. What this study suggests is that we might have to think even earlier. Feeding practices early in life can already have a significant impact on the body size of pre-school children.”

Mass of human chromosomes have been measured for the first time.
The mass of human chromosomes, which contain the instructions for life in nearly every cell of our bodies, has been measured with X-rays for the first time in a new study led by UCL researchers.
For the study, published in Chromosome Research, researchers used a powerful X-ray beam at the UK’s national synchrotron facility, Diamond Light Source, to determine the number of electrons in a spread of 46 chromosomes which they used to calculate mass.
They found that the chromosomes were about 20 times heavier than the DNA they contained — a much larger mass than previously expected, suggesting there might be missing components yet to be discovered.
As well as DNA, chromosomes consist of proteins that serve a variety of functions, from reading the DNA to regulating processes of cell division to tightly packaging two-metre strands of DNA into our cells.
Senior author Professor Ian Robinson (London Centre for Nanotechnology at UCL) said: “Chromosomes have been investigated by scientists for 130 years but there are still parts of these complex structures that are poorly understood.

Researchers at Children’s Hospital of Philadelphia (CHOP) have developed a proof-of-concept treatment for blood disorders like sickle cell disease and beta-thalassemia that could raise hemoglobin levels by activating production of both fetal and adult hemoglobin. Using a viral vector engineered to reactivate fetal hemoglobin production, suppress mutant hemoglobin, and supply functional adult hemoglobin, the researchers developed an approach that could produce more hemoglobin through a single vector. The results were published in Haematologica.
“Until now, researchers have been exploring one of two approaches to treating blood disorders like sickle cell disease or beta-thalassemia: adding a functional copy of the adult hemoglobin gene, or increasing production of fetal hemoglobin,” said senior author Stefano Rivella, PhD, Kwame Ohene-Frempong Chair on Sickle Cell Anemia and Professor of Pediatrics at CHOP. “In this study, we have done both simultaneously, which provides an opportunity to produce more hemoglobin per vector in these patients.”
Sickle cell disease and beta-thalassemia are genetic blood disorders caused by errors in the genes for hemoglobin, a protein that is found in red blood cells and carries oxygen from the lungs to tissues throughout the body. In utero, the gamma-globin gene produces fetal hemoglobin, but after birth, this gene is switched off and the beta-globin gene is turned on, producing adult hemoglobin. Patients with sickle cell disease and beta-thalassemia have mutations in the beta-globin gene, which leads to mutant hemoglobin production and, as a consequence, serious health complications, ranging from delayed growth and jaundice to pain crises, pulmonary hypertension, and stroke.
Current research has focused on treating these blood disorders by either increasing fetal hemoglobin, which is not mutated in these conditions, or adding back a functional copy of adult hemoglobin via gene therapy, using an engineered vehicle known as a viral vector to supply new genetic material. However, there are limitations to both of these approaches, and neither has been established as a fully curative approach.
In order to increase hemoglobin levels in one therapy, the researchers — led by co-first authors Danuta Jarocha, PhD and Silvia Lourenco, PhD — combined the two tactics into a single gene therapy vector. To do so, they focused on a transcription factor called BCL11A, which effectively operates the switch that turns off the production of fetal hemoglobin and turns on the production of adult hemoglobin. The researchers hypothesized that if they could use an engineered vector to repress BCL11A, which would keep fetal hemoglobin production turned on and turn off the production of mutant adult hemoglobin, while also adding back a functional copy of the beta-globin gene, they could induce greater hemoglobin production.
Working in cell lines of patients with sickle cell disease and beta-thalassemia, the researchers tested their vector — which included a gene coding for adult hemoglobin and a microRNA sequence that would target BCL11A — and found that the vector was able to elevate fetal and adult hemoglobin simultaneously in vitro. Although BCL11A was not completely knocked down, the suppression was sufficient to reduce production of the mutant adult hemoglobin. By elevating both fetal and functional adult hemoglobin, the vector was able to induce more functional hemoglobin production than that of a vector expressing beta-globin alone.
“Future studies will evaluate this approach using an even stronger vector that we developed in our lab and published on recently,” Rivella said. “Combining these two technologies, we hope to make an even more powerful vector that can provide curative levels of hemoglobin to these patients.”
This research was supported by the CuRED Frontier Program at CHOP, which is dedicated to finding new and improved curative therapies for blood disorders like sickle cell disease and beta-thalassemia.
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Materials provided by Children’s Hospital of Philadelphia. Note: Content may be edited for style and length.

Getting enough sleep can be a real challenge for shift workers affecting their overall health. But what role does being an early bird or night owl play in getting good rest? Researchers from McGill University find a link between chronotype and amount of sleep shift workers can get with their irregular schedules.
“Some people seem to be hardwired to sleep early, while others tend to sleep late. This preference, called chronotype, is modulated by our circadian system — each person’s unique internal timekeeper,” says lead author Diane B. Boivin, a Professor in the Department of Psychiatry at McGill University.
Their study published in Sleep is the first to examine the relationship between chronotype and sleep behaviour in shift workers during morning, evening, and night shifts. To investigate this relationship, the researchers tracked 74 police officers as they worked their usual shifts. For close to a month, the officers wore a watch-like device, allowing researchers to measure their sleep.
Not all shifts created equal
“Our results suggest that the effect of chronotype on sleep duration and napping behavior depends on the shift type. On average early risers sleep 1.1 hours longer on morning shifts, while night owls sleep two hours longer on evening shifts,” says co-author Laura Kervezee, a former Postdoctoral Fellow at The Douglas Research Centre affiliated with McGill University.
The power of naps
While shift workers take naps to reduce the effect of their irregular schedules on their sleep, the researchers found this behaviour was more prominent during night shifts in early risers. Generally, early risers slept less after night shifts compared to night owls — but they also took more naps prior to their night shifts, so their total daily sleep was similar.
The findings could help design strategies to improve sleep in workers with atypical schedules, the researchers say. Such strategies could include work schedules that consider chronobiological principles.
“People involved in shift work experience an increased risk of sleep disturbances and fragmented sleep periods. Since sleep is essential for optimal performance, health, and well-being, it’s important to develop strategies to get better rest,” says Boivin, who is also the Director of the Centre for Study and Treatment of Circadian Rhythms at The Douglas Research Centre.
As next steps, the researchers hope to study the impact of chronotype and shift work on other health outcomes.
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Materials provided by McGill University. Note: Content may be edited for style and length.