Month: April 2023

Categories : Cardiovascular DiseaseTags :

Sedentary Time may Significantly Enlarge Teens’ Hearts

On By ModernMedia
Photo by Steinar Engeland on Unsplash

In adolescents, sedentary time may increase heart size three times more than moderate-to-vigorous physical activity, according to a paper published in the Scandinavian Journal of Medicine & Science in Sports. The British and Finnish researchers explored the associations of sedentary time, light physical activity, and moderate-to-vigorous physical activity with cardiac structure and function.

Recent World Health Organization reports and guidelines note that more than 80% of adolescents across the globe have insufficient physical activity per day. Physical inactivity has been associated with several non-communicable diseases in adults such as cardiovascular diseases, type 2 diabetes, and cancer. In the pediatric population, the majority of movement behaviour studies have focused on the effect of sedentary behaviour and physical activity on cardiometabolic health which includes blood pressure, insulin resistance, blood lipids, and body mass index.

There has been a gap in knowledge on the effect of sedentary time and moderate-to-vigorous physical activity on cardiac structure and function in large adolescent populations due to the scarcity of device-measured movement behaviour and echocardiography assessment in the pediatric population. A higher left ventricular mass, which indicates an enlarged or hypertrophied heart, and a reduced left ventricular function, which indicates decreased heart function, may in combination or independently lead to an increased risk of heart failure, myocardial infarction, stroke, and premature cardiovascular death.

The current study, which used data from the University of Bristol study Children of the 90s (also known as the Avon Longitudinal Study of Parents and Children) included 530 adolescents aged 17 years who had complete measurements of fat mass, muscle mass, glucose, lipids, an inflammation marker, insulin, smoking status, socio-economic status, family history of cardiovascular disease, echocardiographic cardiac function and structure measures, and accelerometer-based measure of sedentary time, light physical activity, and moderate-to-vigorous physical activity.

On average, adolescents spent almost 8 hours/day sedentary and about 49 minutes/day in moderate-to-vigorous physical activity in this new study. It was observed that both sedentary time and moderate-to-vigorous physical activity were associated with higher left ventricular mass. However, the increase in cardiac mass (3.8g/m2.7) associated with sedentary time was three times higher than the cardiac mass increase (1.2g/m2.7) associated with moderate-to-vigorous physical activity. This finding was observed in adolescents irrespective of their obesity status, ie among adolescents who had normal weight and those who were overweight or obese. Importantly, light physical activity was not associated with an increase in cardiac mass but was associated with better cardiac function estimated from left ventricular diastolic function.

“This novel evidence extends our knowledge of the adverse effects of sedentary time on cardiac health. It is known among adults that a 5g/m2 increase in cardiac mass may increase the risk of cardiovascular disease and death by 7–20%. Engaging in moderate-to-vigorous physical activity also slightly enlarged the heart but it seems an acceptable negative side effect considering several other health benefits of moderate-to-vigorous exercise. Hence, public health experts, health policymakers, high school administrators and teachers, paediatricians, and caregivers are encouraged to facilitate adolescent participation in physical activity to enable a healthy heart,” says Andrew Agbaje, a physician and clinical epidemiologist at the University of Eastern Finland.

Source: University of Eastern Finland

Categories : Addiction Mental HealthTags :

ADHD Stimulant Drugs have Potential for Abuse at Schools that Carry Them

On By ModernMedia
Photo by Myriam Zilles on Unsplash

Researchers have identified a strong association between prevalence of prescription stimulant therapy for attention-deficit/hyperactivity disorder (ADHD) and rates of prescription stimulant misuse by students in US middle and high schools. Published in JAMA Network Open, the study highlights the need for assessments and education in schools and communities to prevent medication-sharing among teens. This is especially important considering non-medical use of prescription stimulants among teens remains more prevalent [PDF] than misuse of any other prescription drug, including opioids and benzodiazepines.  

The study used data collected between 2005 and 2020 by the Monitoring the Future (MTF) study. MTF is a large, multicohort survey of legal and illicit drug use among American adolescents in eighth, 10th, and 12th grade.

“The drug supply has rapidly changed, and what looks like medications – bought online or shared among friends or family members – can contain fentanyl or other potent illicit substances that can result in overdoses. It’s important to raise awareness of these new risks for teens,” said NIDA Director Nora Volkow, MD. “It’s also essential to provide the necessary resources and education to prevent misuse and support teens during this critical period in their lives when they encounter unique experiences and new stressors.”

Stimulant therapy is an evidence-based treatment for ADHD, but it can also be harmful if used without prescription or guidance from clinicians. Prolonged stimulant misuse can lead to several detrimental health effects including cardiovascular conditions, depressed mood, overdoses, psychosis, anxiety, seizures, and stimulant use disorder.

Previous studies have shown that more than half of adolescents who misuse prescription stimulants get the medication for free from friends or relatives. While diagnoses of ADHD and prescribing of stimulant therapy for ADHD have increased significantly in the United States over the past 20 years, few studies have looked at the relationship between stimulant therapy and prescription stimulant misuse in schools. This is the first large, national study to examine prevalence of prescription stimulant misuse and factors correlating with prevalence among students in eighth, 10th, and 12th grade across the U.S.

Researchers at the University of Michigan examined both school- and individual-level characteristics associated with prescription stimulant misuse. Across 231 141 student participants surveyed at 3,284 secondary schools, the school-level prevalence of nonmedical use varied from 0% to over 25% of students. Schools with a greater number of students (12% or higher) reporting prescription stimulant therapy for ADHD tended to have the highest percentages of their student body reporting prescription stimulant misuse (8% of total student body). By comparison, schools with fewer students (0 to 6% of student body) reporting stimulant therapy for ADHD were associated with lower rates of prescription stimulant misuse (4 to 5% of student body).

Other features of schools that were associated with increased rates of misuse included having a higher proportion of parents with higher levels of education, being located in non-Northeastern regions of the US and in suburban areas, having a higher proportion of non-Hispanic white students, and showing “medium-level” (10-19% of total student body) binge drinking. However, the association between school prevalence of stimulant therapy for ADHD and prescription stimulant misuse remained strong when accounting for prevalence of other types of substance use and numerous other individual- and school-level sociodemographics.

Recent research from this team expands on the associations found in this study, including a study that suggested teens with a history of taking both stimulant or non-stimulant medications for ADHD are at high risk for prescription stimulant misuse, as well as cocaine and methamphetamine use. The researchers note that it is important to interpret these results as associations, not causations, and that the primary goal of these kinds of studies is to inform effective preventative and support [PDF] strategies for teens.

“The key takeaway here is not that we need to lessen prescribing of stimulants for students who need them, but that we need better ways to store, monitor, and screen for stimulant access and use among youth to prevent misuse,” said study author Sean Esteban McCabe, PhD. “There’s variation in stimulant misuse across different schools, so it’s important to assess schools and implement personalised interventions that work best for each school. It’s also critical to treat and educate teens on prescription stimulants as the medications they are intended to be and limit their availability as drugs of misuse.”

Source: National Institutes of Health

Categories : Exercise NeurologyTags :

Dopamine’s Role in Exercise Feeling ‘Hard’ or ‘Easy’

On By ModernMedia
Photo by Jonathan Borba on Unsplash

Dopamine, long associated with pleasure, motivation and reward-seeking, also appears to play an important role in why exercise and other physical efforts feel ‘easy’ to some people and exhausting to others. These are the findings of of a study of people with Parkinson’s disease, which is published in NPG Parkinson’s Disease. Parkinson’s disease is marked by a loss of dopamine-producing cells in the brain over time.

According to the researchers, the findings might eventually lead to more effective ways to help people establish and stick with exercise regimens, new treatments for fatigue associated with depression and many other conditions, and a better understanding of Parkinson’s disease.

“Researchers have long been trying to understand why some people find physical effort easier than others,” says study leader Vikram Chib, Ph.D., associate professor in the Department of Biomedical Engineering at the Johns Hopkins University School of Medicine and research scientist at the Kennedy Krieger Institute. “This study’s results suggest that the amount of dopamine availability in the brain is a key factor.”

Chib explains that after a bout of physical activity, people’s perception and self-reports of the effort they expended varies, and also guides their decisions about undertaking future exertions. Previous studies have shown that people with increased dopamine are more willing to exert physical effort for rewards, but the current study focuses on dopamine’s role in people’s self-assessment of effort needed for a physical task, without the promise of a reward.

For the study, Chib and his colleagues from Johns Hopkins Medicine and the Kennedy Krieger Institute recruited 19 adults diagnosed with Parkinson’s disease, a condition in which neurons in the brain that produce dopamine gradually die off, causing unintended and uncontrollable movements such as tremors, fatigue, stiffness and trouble with balance or coordination.

In Chib’s lab, 10 male volunteers and nine female volunteers with an average age of 67 were asked to perform the same physical task, that of squeezing a hand grip equipped with a sensor, on two different days within four weeks of each other. On one of the days, the patients were asked to take their standard, daily synthetic dopamine medication as they normally would. On the other, they were asked not to take their medication for at least 12 hours prior to performing the squeeze test.

On both days, the patients were initially taught to squeeze a grip sensor at various levels of defined effort, and then were asked to squeeze and report how many units of effort they put forth.

When the participants had taken their regular synthetic dopamine medication, their self-assessments of units of effort expended were more accurate than when they hadn’t taken the drug. They also had less variability in their efforts, showing accurate squeezes when the researchers cued them to squeeze at different levels of effort.

In contrast, when the patients hadn’t taken the medication, they consistently over-reported their efforts, meaning they perceived the task to be physically harder, and had significantly more variability among grips after being cued.

In another experiment, the patients were given a choice between a sure option of squeezing with a relatively low amount of effort on the grip sensor or flipping a coin and taking a chance on having to perform either no effort or a very high level of effort. When these volunteers had taken their medication, they were more willing to take a chance on having to perform a higher amount of effort than when they didn’t take their medication.

A third experiment offered participants the choice between getting a small amount of guaranteed money or, getting either nothing or a higher amount of money on a coin flip. Results showed no difference in the subjects on days when they took their medication and when they did not. This result, researchers say, suggests that dopamine’s influence on risk-taking preferences is specific to physical effort-based decision-making.

Together, Chib says, these findings suggest that dopamine level is a critical factor in helping people accurately assess how much effort a physical task requires, which can significantly affect how much effort they’re willing to put forth for future tasks. For example, if someone perceives that a physical task will take an extraordinary amount of effort, they may be less motivated to do it.

Understanding more about the chemistry and biology of motivation could advance ways to motivate exercise and physical therapy regimens, Chib says. In addition, inefficient dopamine signalling could help explain the pervasive fatigue present in conditions such as depression and long COVID, and during cancer treatments. Currently, he and his colleagues are studying dopamine’s role in clinical fatigue.

Source: John Hopkins Medicine

Categories : Skeletal SystemTags :

Changes in Hyaluronic Acid Properties Drive Osteoarthritis

On By ModernMedia
Source: CC0

The composition of synovial fluid changes significantly in osteoarthritis: The concentration and molecular weight of hyaluronic acid tends to decrease and is commonly used to diagnose the disease. An international group of researchers explored the disease-driven breakdown of hyaluronan and the mechanistic implications of these changes on the lubrication and subsequent wear of joints.

“One of the most important properties of the synovial fluid is its viscosity,” said Rosa Maria Espinosa-Marzal, co-author of the study published in the journal Biointerphases. “Viscosity is a measure of the internal frictional force between adjacent layers of a fluid in relative motion, or, more simply, a fluid’s resistance to flow. Large, high molecular weight polymers such as hyaluronic acid play a significant role in maintaining a high viscosity of the synovial fluid, which helps maintain a fluid film and reduces friction between articulating surfaces during motion.”

Through analysis with neutron and light scattering, the team determined that the structure of the lipid-hyaluronic-acid complexes in the bulk solution is a function of concentration and its molecular weight.

The researchers found the hyaluronic acid’s concentration and molecular weight both play a role in how the lubricant reacts with different surfaces.

“Our results show low molecular weight hyaluronic acid, which mimics osteoarthritis-diseased joints, hinders the adsorption of the hyaluronic-acid-lipid complex,” said Espinosa-Marzal, of the University of Illinois Urbana-Champaign. “The lack of the formation of an amorphous film on the surface may reflect a consequence of osteoarthritis, since this film should help reduce friction and wear.”

Their hypothesis is that this film’s absence may increase wear of the cartilage surface. In contrast, high molecular weight hyaluronic-acid-lipid complexes form an amorphous film, which presumably helps maintain the mechanical integrity and longevity of efficient lubrication in healthy cartilage.

Studies on hyaluronic acid itself and hyaluronic-acid-lipid complexes “do not entirely support hyaluronic acid’s role in providing high lubricity to the cartilage’s articular surface, which is still a bit controversial,” Espinosa-Marzal said. “Our results indicate that for low molecular weight hyaluronic acid, this is likely the case.”

By exploring the complex interplay between phospholipid and hyaluronic acid self-assembly, and the role of molecular weight on surface affinity, “our study illuminates a mechanism whereby the ‘vicious circle’ of osteoarthritis can be explained,” said co-author Mark Rutland, from KTH Royal Institute of Technology.

Source: American Institute of Physics

Categories : Cardiovascular DiseaseTags :

Scientists ‘Poke the Bear’ to Gain a Better Understanding of Blood Clotting

On By ModernMedia
Photo by Mark Basarab on Unsplash

It’s generally good advice not to “poke the bear” as they say, but that’s exactly what a multinational team of scientists have been doing, to discover the secrets of blood clotting. Hibernating bears, paralysed humans, and pigs kept in small enclosures all avoid dangerous blood clots, despite being immobile for extremely long periods.

Their new study published in Science shows that reduction of a key protein inhibits the formation of blood clots in all three mammal species when they are immobile for days, months or even years.

Passengers on long haul flights run the risk of developing deep vein thrombosis if they do not take some time to walk around and use compression socks. Some people are predisposed to blood clots, due to genetic factors.

Yet, when humans – and other mammals such as bears – are immobilised for a much longer period than a flight, the researchers found that a protein known as Hsp47 is reduced by 55 times. This could lead to new medicines to help those who have inherited blood clotting disorders that put them at risk for pulmonary embolism, heart attack, and stroke.

Professor Jon Gibbins led the work at the University of Reading. He said: “It seems counterintuitive that people who have severe paralysis don’t appear to be at higher risk of blood clots. This tells us that something interesting is happening. And it turns out that reducing levels of Hsp47 plays a key role in preventing clots, not just in humans, but in other mammals, including bears and pigs.

“When we see something like this in multiple species, that reinforces its importance. Having Hsp47 must have been an evolutionary advantage.”

Hsp47 is released by platelets – the sticky blood cells that trigger blood clotting.  Usually clotting is an important response to an injury, to prevent blood loss, and Hsp47 is one of the necessary ingredients to enable platelets to do their job. Examining the role of Hsp47 in clotting function the team found that when released into the blood of bears, mice and humans that it promoted conditions that may give rise to deep vein thrombosis.

Professor Gibbins said, “We aren’t totally sure how, but it appears that there is something about movement that keeps Hsp47 at an appropriate level. It could be that the mechanical forces involved in moving around actually have an impact on gene expression, dramatically increasing the amount of Hsp47 that circulates in the blood.”

The team took blood samples from bears in winter, while hibernating, and in summer, while awake and moving around. They also compared people who were immobilised with those who can move and walk. And finally, pigs kept in small pens were compared with others that were free to move around in barns. In all three cases, proteomics experiments showed that the absence of movement was associated with having far less Hsp47.

Professor Gibbins continued: “Now we know that Hsp47 is so important, we can begin to look for new or existing medicines that might be able to inhibit the function of this protein in blood clotting and protect mobile people who are prone to clots.”

Source: University of Reading

Categories : Regenerative MedicineTags :

Cultured Cells may Restore Vision Lost to Photoreceptor Damage

On By ModernMedia

A preclinical study that produced progenitor photoreceptor cells and transplanted them into experimental models of damaged retinas has resulted in significant vision recovery. This finding marks a first step towards potentially restoring vision in eye diseases characterised by photoreceptor loss.

“Our laboratory has developed a novel method that enables the production of photoreceptor progenitor cells resembling those in human embryos,” said Assistant Professor Tay Hwee Goon, first author of the study published in Molecular Therapy. “Transplantation of these cells into experimental models has yielded partial restoration of the retinal function.”

The degeneration of photoreceptors in the eye is a significant cause of declining vision that can eventually lead to blindness and for which there is currently no effective treatment. Photoreceptor degeneration occurs in a variety of inherited retinal diseases, such as retinitis pigmentosa, a rare eye disease that breaks down cells in the retina over time and eventually causes vision loss, and age-related macular degeneration, a leading cause of vision impairment worldwide.

Asst Prof Tay and her team from Duke-NUS Medical School, the Singapore Eye Research Institute and the Karolinska Institute in Sweden, developed a procedure to grow human embryonic stem cells in the presence of purified laminin proteins. These proteins are involved in normal development of human retinas, and in their presence, stem cells could be directed to differentiate into photoreceptor progenitor cells responsible for converting light into signals that are sent to the brain.

When these cells were transplanted into damaged retinas, the preclinical models showed significant recovery of vision. A diagnostic test called electroretinogram also identified significant recovery in the retinas via electrical activity in the retina in response to a light stimulus. The transplanted cells established connections with surrounding retinal cells and nerves in the inner retina. They also survived and functioned for many weeks after transplantation.

Moving forward, the team hopes to refine their method to make it simpler and achieve more consistent results than earlier attempts to explore stem cell therapy for photoreceptor cell replacement.

“It is exciting to find these results, which suggest a promising route towards using stem cells to treat those forms of visual deterioration and blindness caused by the loss of photoreceptors,” said Dr Helder Andre, Head of Molecular and Cellular Research from Karolinska Institute’s Department of Clinical Neuroscience and a senior author of the study.

Associate Professor Enrico Petretto, Director of the Centre for Computational Biology at Duke-NUS and the study’s bioinformatics analysis lead, added: “Our method may also be useful for understanding the molecular and cellular pathways that drive the progression of macular degeneration, perhaps leading to the development of other therapeutic approaches.”

The next challenge for the researchers is to explore the efficacy of their method in models of photoreceptor degeneration that more closely match the human condition.

“If we get promising results in our future studies, we hope to move to clinical trials in patients,” said Professor Karl Tryggvason, from Duke-NUS’ Cardiovascular and Metabolic Disorders Programme, and the corresponding author of the study. “That would be an important step towards for being able to reverse damage of the retina and restore vision.”

Source: Duke-NUS Medical School

Categories : Diseases, Syndromes and ConditionsTags :

Real-world Testing Confirms Bulevirtide Efficacy in Treating Hepatitis D

On By ModernMedia
Colourised transmission electron micrograph of hepatitis B virus particles (colourised red and yellow). Credit: NIAID and CDC (Transmission electron micrograph image courtesy of CDC; colourisation by NIAID).

In 2020, bulevirtide (BLV) was conditionally approved for treating chronic hepatitis delta (CHD), an inflammation of the liver caused by hepatitis D virus (HDV). Now, as reported in the Journal of Hepatology, real-world studies confirm that long-term suppressive therapy with BLV monotherapy reduces viral replication and improves liver tests of these difficult-to-treat patients.

Two of the studies, led by Pietro Lampertico, MD, PhD, were designed to assess the effectiveness and safety of patients with advanced HDV-related compensated cirrhosis being treated with BLV 2mg monotherapy and the consequences of discontinuing this treatment.

“HDV is the most severe form of chronic viral hepatitis,” explained Dr Lampertico. “For many years, the only therapeutic option was the off-label administration of pegylated-interferon-alpha (PegIFNa), an approach characterised by suboptimal efficacy, an unfavourable safety profile and several contraindications.”

In a study of 18 patients with HDV-related advanced cirrhosis treated with BLV 2mg/day for 48 weeks, Dr. Lampertico and colleagues demonstrated significant virological, biochemical and combined response rates associated with improvement of liver function.

“The efficacy and safety of BLV monotherapy in patients with advanced compensated cirrhosis were unknown before this study. Virological and biochemical responses to BLV monotherapy that we observed in our difficult-to-treat patients with HDV-related compensated cirrhosis were similar to those shown in the phase III registration study,” Dr Lampertico noted.

In a case report, Dr Lampertico and colleagues demonstrated that HDV could be successfully eradicated from both serum and liver following a three-year course of BLV monotherapy. This was despite the persistence of HBsAg, in a patient with HDV-related compensated cirrhosis and oesophageal varices. During the 72-week off-BLV follow-up, liver biopsy, intrahepatic HDV RNA and hepatitis D antigen were undetectable, less than 1% of hepatocytes were HBsAg positive and all were negative for hepatitis B core antigen.

“We were surprised to demonstrate that HDV can be eradicated following a finite course of an entry inhibitor administered as monotherapy such as BLV 2mg/day, despite the persistence of HBsAg positivity,” commented Dr Lampertico.

In a study in JHEP Reports led by Katja Deterding, MD, investigators report the first data from the largest multicentre cohort of patients to date who were treated with BLV under real-world conditions. This included 50 patients with signs of significant portal hypertension, elevated pressure in the major vein that leads to the liver.

The retrospective analysis of 114 cases covered 4289 patient weeks of BLV treatment. Viral response was observed in 87 cases while hepatic inflammation improved, and treatment was well tolerated. More than 50% of patients showed a virologic response with less than 10% of patients not achieving an HDV RNA drop of at least 90% after 24 weeks. An improvement of biochemical hepatitis activity as measured by the liver enzyme alanine transaminase (ALT) values was observed regardless of virologic response. Investigators concluded that treatment was safe and well tolerated and associated with improvements in liver cirrhosis and portal hypertension with prolonged treatment.

“In line with other real-world cohorts and clinical trials our real-world study confirms the antiviral activity of BLV,” noted Dr Deterding. “We were surprised to see an improvement in biochemical hepatitis activity even in cases without viral response. Potential explanations for this phenomenon include anti-inflammatory properties of BLV.”

“This is the first time that patients with HDV-related chronic advanced liver disease can be treated with an antiviral therapy since 1977 when HDV was discovered. Long-term suppressive therapy with BLV 2mg/day has the potential to improve survival, of these difficult-to-treat patients for the first time in 45 years,” concluded Dr Lampertico. “We also found that BLV treatment can be successfully discontinued in some HDV patients who achieved long-term viral suppression while on therapy.”

HDV infection occurs when people become infected with both hepatitis B and D virus either simultaneously (co-infection) or acquire the hepatitis D virus after first being infected with hepatitis B (super-infection). According to the World Health Organization, HDV affects nearly 5% of individuals with a chronic infection resulting from hepatitis B virus (HBV). Populations that are more likely to have HBV and HDV co-infection include indigenous populations, haemodialysis recipients and individuals who inject drugs.

Source: Elsevier

Categories : Genetics Skeletal SystemTags :

Scientists Close in on the Genetic Determinants of Height

On By ModernMedia
Pexels Photo by Monstera

Human height is dictated by the sealing of the growth plates at the ends of bones that harden as a child develops. Along with diet and disease, heritability has long been known to be a factor determining height. Now, researchers report in Cell Genomics that cells in these plates determine the length and shape of bones and may partly predict final stature. The study identified potential “height genes” and found that genetic changes affecting cartilage cell maturation may strongly influence adult height.

“The study is really understanding the genetics of skeleton,” says paediatric endocrinologist and senior author Nora Renthal of Boston Children’s Hospital and Harvard University. “Height is a good starting point to understand the relationship between genes, growth plates, and skeletal growth because we can measure the height of every human being.”

To pinpoint height-associated genes, the team screened 600 million mouse cartilage cells to identify genes that, when deleted, can alter cell growth and maturation. These types of cellular changes in the growth plate are known to lead to variations in human height. The search turned up 145 genes mostly linked to skeletal disorders and are crucial for growth plate maturation and bone formation.

The team then compared these genes with data from genome-wide association studies (GWAS) of human height, which located “hotspots” along the entire human genome where “height genes” are located. But these regions can contain multiple genes, making it hard for researchers to track down and study an individual target.

“That’s kind of like looking for your friend’s house, but you only know the zip code,” says Renthal. “It’s difficult.”

The comparison revealed that genes affecting cartilage cells overlap with hotspots from human height GWAS, precisely locating genes in our DNA that likely play a role in determining our stature. Renthal and her team also discovered that many of the GWAS suggested height genes led to early maturation in cartilage cells. These findings suggest that genetic changes affecting cartilage cell maturation may influence height more.

Renthal notes that studies in mouse cells may not fully translate to humans, and GWAS are observational studies that cannot fully illustrate the cause and effects of height. But her study provides a novel method to bridge the two methods and provide new insights into human genetics.

Next, the team plans to use the method to understand hormones’ effect on cartilage cells. They will also look into some of the 145 genes that have no known connection to skeletal growth. The investigation may reveal new genes and pathways that play a role in the bones.

“I see patients with skeletal dysplasia, where there isn’t any treatment because genetics made their bones grow this way,” says Renthal. “It’s my hope that the more we can understand about the biology of the growth plate, the more we would be able to intervene at earlier times in growing skeletons and the life of a kid.”

Source: MedicalXpress

Categories : Gender Mental HealthTags :

Researchers Tie Sex-specific Genes to Depression

On By ModernMedia
Photo by Sydney Sims on Unsplash

Depression is widely reported to be more common in women than in men, with women twice as likely to receive a diagnosis than men. A new study published in Nature has found that there are differences between male and female genes and how they relate to depression.

In a genome-wide association(GWA} study, the McGill University researchers analysed the genomes of more than 270 000 individuals. They found that sex-specific prediction methods were more accurate in forecasting an individual’s genetic risk of developing depression than prediction methods that did not specify sex. The researchers found 11 areas of DNA that were linked to depression in females, and only one area in males.

In both males and females, genetic correlations were significant between the broad depression GWA and other psychopathologies; however, correlations with educational attainment and metabolic features including body fat, waist circumference, waist-to-hip ratio and triglycerides were significant only in females. Gene-based analysis showed 147 genes significantly associated with broad depression in the total sample, 64 in the females and 53 in the males.

Despite the biological processes involved in depression being similar in males and females, researchers found that different genes were involved for each sex. This information can be useful to identify future sex-specific treatments for depression.  “This is the first study to describe sex-specific genetic variants associated with depression, which is a very prevalent disease in both males and females. These findings are important to inform the development of specific therapies that will benefit both men and women while accounting for their differences,” says Dr Patricia Pelufo Silveira, lead author and Associate Professor in the Department of Psychiatry. “In the clinic, the presentation of depression is very different for men and women, as well as their response to treatment, but we have very little understanding of why this happens at the moment.”

Source: McGill University

Categories : HIVTags :

Abbott Partnership to Bring Affordable Blood-based HIV Self-test Kits to SA

On By ModernMedia

HIV testing is essential across the continuum of care but too often unavailable, unaffordable, or inaccessible. Abbott, the global leader in diagnostics and the fight against HIV, is partnering with Population Services International (PSI) and Unitaid to make HIV self-testing (HIVST) available at an affordable and accessible price. An initial 400 000 tests will be distributed within Africa.

This vital partnership serves as an early market access vehicle to enable affordable access to high-quality self-test kits in high HIV burden settings with a dire need for access to healthcare services, while mitigating risks such as increased supply chain costs and custom fees. People who test positive will undergo confirmatory testing and will be linked to antiretroviral treatment, keeping them healthy and helping reduce further transmission to others.

“With millions of people living with HIV worldwide, many of whom who do not know their status, receiving a diagnosis is a vital first step in accessing treatment”, says Bassem Bibi, divisional vice president, for Abbott’s rapid diagnostics business for EEMEA. “This is why this partnership is so important to Abbott as it reinforces our commitment to enabling people in Africa to live healthier, fuller lives, by improving testing capabilities through high quality and affordable blood-based HIV self-tests.”

“Self-testing has shifted the paradigm for HIV testing.  The HIV Self-Testing Africa (STAR) Initiative amassed compelling evidence that HIVST can reach more people than traditional diagnostics. It offers an alternative option to people living with HIV to find out about their status and to access anti-retroviral treatment services. Self-testing is a critical entry point to HIV prevention services for those testing negative, including the delivery of Pre-Exposure Prophylaxis (PrEP). It is also useful for screening in health facilities and to keep services going during COVID-19 and any future emergencies. We require more product options to meet the growing demand,” said Dr Karin Hatzold, Director of the STAR Initiative Project and Associate Director of HIV/TB Programs at PSI. “This important partnership under the early market access vehicle will make it easier for countries to acquire products and embed them in health systems. This will ensure that self-test kits are affordable to those who want to access them.”  

The Abbott HIV self-test kits will be distributed strategically to communities with inadequate access to healthcare services and will help build capacity to meet the UNAIDS 95-95-95 targets for 2025. The 95-95-95 targets stipulate that 95% of people living with HIV know their status; 95% of people who know their status are on antiretroviral therapy; and 95% of people on treatment have suppressed viral loads.

“Self-testing has helped us reach beyond health centres and make testing easier. This is critically important for vulnerable groups who are often at higher risk of HIV but may also be hesitant to access health services for fear of stigma, discrimination, and violence,” said Dr Philippe Duneton, executive director of Unitaid. “Making quality self-testing kits widely available and affordable is vital to reaching people at risk of HIV with the opportunity to test privately and access life-saving care.”