Day: March 11, 2021

Retinal Images Could Provide Stroke and Dementia Warning

In the future, images of the retina could warn of a person’s increased risk of stroke and dementia, making it possible to take preventive measures.

These findings come from preliminary research to be presented at the American Stroke Association’s International Stroke Conference 2021.

Retinopathy is damage to the retina from injury or disease, commonly associated with diabetes. People with severe retinopathy are more likely to have a diseased-looking brain on magnetic resonance imaging (MRI). Retinal tissue has the highest consumption of oxygen in the body, and is the most vulnerable to oxidative stress. Most causes of retinopathy involve damage to the retinal and choroidal circulatory systems.

Study Lead Author Michelle P  Lin, MD., MPH, Neurologist at Mayo Clinic explained:”The retina is a window to the brain. A retinal photo that shows a magnified look at the back of the eye, including the retina and optic nerve, is cheaper and faster to perform than an MRI, so we’re wondering if it might be a good screening tool to see who could benefit from a referral to a neurologist for a brain MRI.”

In addition to the ophthalmologist’s office, retinal photos could be taken by a smartphone camera or via a smartphone adapter, Lin said.

Researchers explored the association of retinopathy with stroke, dementia, and the risk of death in 5543 adults who had participated in the annual US National Health and Nutrition Examination Surveys (NHANES) from 2005 to 2008. Interviews were conducted with the participants on a number of aspects of their medical history and health behaviours. Additionally, they received a retinal scan photo to look for signs of retinopathy.

Compared with participants not diagnosed with retinopathy, those with retinopathy were more than twice as likely to have had a stroke. They were also  nearly 70% more likely to have dementia; and more likely to die within the next 10 years, with increasing severity of retinopathy conferring a higher risk of death. The odds were calculated after adjusting for risk factors such as age, hypertension, diabetes and smoking.

“If you have retinopathy, work closely with your primary care doctor to alter your vascular risk factors and ask to be screened for cognitive impairment. You may be referred to a neurologist for evaluation and possibly a brain MRI,” said Dr Lin, who is also an assistant professor of neurology at the Mayo Clinic College of Medicine.

Source: News-Medical.Net

Article Highlights Lack of Healthcare’s Anaemia Support for Women

An article entitled  “The misogyny of iron deficiency”, published today in Anesthesia addresses the history of anaemia and how women’s health has often been overlooked.

The article was written by researchers from The University of Western Australia and University College London coincides with International Women’s Day. Sex differences in haemoglobin begins in puberty due to the effects of menstruation on iron stores and also varies by age, and can be affected by factors such as smoking and pregnancy.

Team lead Professor Toby Richards, Lawrence-Brown Chair in Vascular Surgery at UWA, is calling for greater recognition and equality for women’s health. He said that one in three women would need to take iron supplements at some point in their life.

“Our figures show that up to 18 percent of women who appear fit and healthy are actually deficient in iron, with heavy menstrual bleeding the most common cause. Symptoms reported by women range from fatigue to brain fog, hair loss and eating ice,” Prof Richards said.

Iron deficiency was a particular problem for women involved in fitness or sport with up to one in five athletes affected, he added.

“Issues with a women’s menstrual cycle and particularly heavy periods are surprisingly common and often not recognized with more than half also suffering iron deficiency.

“It’s so common it’s hiding in plain sight and both are under-diagnosed issues in women’s health. Unfortunately, there has been a dogma to accept these as ‘in the normal range’ for women,” said Prof Richards.

Prof Richards’ team also recently surveyed two groups of women, including 68 triathletes and 181 students, at UWA’s recent Orientation Day.

The women completed a simple questionnaire about previous iron status, menstrual blood loss, diet and motherhood. They were then tested for anaemia. Of the 181 women tested 14.5% were anaemic and most were unaware.

“This is alarming that so many apparently fit and healthy women are actually anemic, which may impact on their physical and mental health,” said Prof Richards.

He said many women simply coped with constant tiredness among a host of other symptoms, without addressing the root cause.

“We want to raise awareness of these conditions and help women recognize the signs and symptoms, in order to get the treatment that their body needs to improve their health and welfare.”

Source: News-Medical.Net

A Non-invasive Parkinson’s Test Inspired by Scent

A  skin swab test has been developed for Parkinson’s disease, based on biomarker analysis of sebum, the oils that protect the skin – and it has a surprising inspiration. 

This comes about after the remarkable discovery of a woman’s ability to detect a certain smell in people who had the disease. 

Joy Milne, a retired nurse, noticed a “musky” scent on her husband years before he was diagnosed with Parkinson’s disease. A series of tests showed that she could detect the presence of Parkinson’s disease in people with 100% based on smell alone, prompting research which isolated the compounds she was smelling: higher concentrations of hippuric acid, eicosane, and octadecanal.

In order to exploit these biomarkers, researchers developed a mass spectrometry test to pick up their levels in sebum obtained with skin swabs. This has proved to be around 80% accurate.

Prof Perdita Barran said: “We believe that our results are an extremely encouraging step towards tests that could be used to help diagnose and monitor Parkinson’s.

“Not only is the test quick, simple and painless but it should also be extremely cost-effective because it uses existing technology that is already widely available.

“We are now looking to take our findings forwards to refine the test to improve accuracy even further and to take steps towards making this a test that can be used in the NHS and to develop more precise diagnostics and better treatment for this debilitating condition.”

This new test with its high reliability could help the diagnosis of Parkinson’s disease, which can be easily missed, especially in the early stages.
Daxa Kalayci, 56, was misdiagnosed several times over four years before finally finding out she had Parkinson’s in 2019.

“I was misdiagnosed with anxiety, stress-related tremors and told that my problems stemmed from going through the menopause,” she said.

“Despite my diagnosis eventually being confirmed… a quick and simple diagnostic test for Parkinson’s would have given me the chance to start my treatment earlier and enjoy life a lot more.

“But instead, I lost so many years not being able to pursue a career as a paramedic or go back to nursing.

“This test could be a game-changer for people living with Parkinson’s and searching for answers, like I was.”

Source: BBC News

Bat Coronavirus 94.5% Similar to SARS-CoV-2 Found

Researchers in China and Australia have reported the discovery of novel bat coronaviruses with a similarity of up to 94.5% to SARS-CoV-2. 

This finding further illuminates the diversity and complex evolutionary history of these viruses. A pre-print version of the research paper is available on the bioRxiv server.

Now, Weifeng Shi from Shandong First Medical University & Shandong Academy of Medical Sciences in Taian, China and colleagues have conducted a meta-transcriptomic analysis of samples collected from 23 bat species in Yunnan province in China during 2019 and 2020.  

Using a combination of genome sequencing and sampling studies, researchers identified a number of SARS-CoV-2-related coronaviruses in wildlife species that together pointed to underestimation of the phylogenetic and genomic diversity of coronaviruses.

“Our study highlights both the remarkable diversity of bat viruses at the local scale and that relatives of SARS-CoV-2 and SARS-CoV circulate in wildlife species in a broad geographic region of Southeast Asia and southern China,” said the team.

Bats are hosts to a broad range of viruses that can infect humans, and four of the seven known human coronaviruses have zoonotic origins.  They are also host to many coronaviruses, but sometimes “intermediate” hosts such as dromedary camels (MERS-CoV) are involved in the jump to humans.

Retrospective genome sequencing and sampling studies identified a number of SARS-CoV-2-related coronaviruses in wildlife species. These included the RaTG13 virus, which is the closest known relative of SARS-CoV-2,  found in the Rhinolophus affinis bat. SARS-CoV-2-related viruses have also been identified in various other Rhinolophid bats across Asia.

“Collectively, these studies indicate that bats across a broad swathe of Asia harbour coronaviruses that are closely related to SARS-CoV-2 and that the phylogenetic and genomic diversity of these viruses has likely been underestimated,” said Shi and colleagues.

Notably, one of these novel bat coronaviruses – RpYN06 – exhibited 94.5% sequence identity to SARS-CoV-2 across the whole genome, with key similarities in certain genes. Low genopmic sequence identity in the spike gene made RpYN06 the second closest relative of SARS-CoV-2, next to RaTG13. This is far more similar than seen in other SARS-CoV-2-like viruses identified in wildlife species.

Indeed, while the other three SARS-CoV-2-related viruses identified here were almost identical in sequence, the spike protein sequences formed an independent lineage that was separated from known sarbecoviruses (a  viral subgenus or the coronaviruses that  includesSARS-CoV-2)   by a relatively long branch.

“Collectively, these results highlight the extremely high, and likely underestimated, genetic diversity of the sarbecovirus spike proteins, which likely reflects their adaptive flexibility,” wrote Shi and colleagues.

The researchers say studies have previously shown that host switching of coronaviruses among bats is a frequent occurrence.

Source: News-Medical.Net

Journal information: Shi W, et al. Identification of novel bat coronaviruses sheds light on the evolutionary origins of SARS-CoV-2 and related viruses. bioRxiv. 2021. doi: https://doi.org/10.1101/2021.03.08.434390

Novel Glioblastoma Drug Can Cross The Blood-brain Barrier

An experimental spherical nucleic acid (SNA) drug was able to penetrate the blood-brain barrier and trigger glioblastoma tumour cell death in an early clinical trial.

Glioblastoma is the most common and aggressive brain tumour, accounting for 16% of cases. It affects 3.2 per 100 000 people, at an average age of 64 years although it can appear at any time.

The new drug, NU-0129, is the first SNA drug developed for systemic use. The SNA groups RNA or DNA around a nanoparticle. A revolutionary new class of drugs, it can be adapted to a number of neurological diseases such as Parkinson’s.

“We showed the drug, NU-0129, even at very small doses, causes tumour cells to undergo what’s called apoptosis or programmed cell death,” said lead investigator Dr Priya Kumthekar, associate professor of neurology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine physician. “It’s a remarkable finding in humans that confirms what we had previously seen in our animal studies.”

The study participants received the drug intravenously prior to surgery to remove the tumour. The researchers team studied the tumours to determine how well the drug crossed the blood-brain barrier and its effect on their cells.

“This unique 3D design has the ability to infiltrate tumor cells to correct the genes inside and make them susceptible for therapy-induced killing,” said senior author Alexander Stegh, an associate professor of neurology at Northwestern.

Unusually, the drug was developed entirely within the university without involving pharmaceutical licensing.
“We want to move the technology forward as quickly as possible because there are patients with a disease with no current cure,” Kumthekar said.

Dr Leon Platanias, director of the Lurie Cancer Center, said, “These exciting findings for the first time support the potential of spherical nucleic acids for drug delivery to brain tumors. They may prove to have important long-term translational implications for the treatment of these tumours.”

Source: Medical Xpress

Journal information: P. Kumthekar el al., “A first-in-human phase 0 clinical study of RNA interference–based spherical nucleic acids in patients with recurrent glioblastoma,” Science Translational Medicine (2021). stm.sciencemag.org/lookup/doi/ … scitranslmed.abb3945

Playing with Ultra-thin Dolls Skews Girls’ Ideal Body Size

A small-scale study led by Durham University in the UK, has shown that play with ultra-thin dolls may negatively affect body image in girls as young as five years old.

The researchers warn that the dolls, combined with exposure to ‘thin ideals’ in the media, could lead to body dissatisfaction in young girls, which has been shown to be a factor in the development of eating disorders. A Dutch study showed that girls randomised to receive an ultra-thin doll to play with ate less than those who received a realistic adult doll.

The study had 30 girls aged between 5-9 years old play with an ultra-thin doll, a realistic childlike doll or a car. Before and after each play session, the girls were asked about their perceived own body size and ideal body size via an interactive computer test using pictures.

Playing with the ultra-thin dolls reduced girls’ ideal body size immediately after play. There was no improvement even when they subsequently played with the childlike dolls or cars afterwards, demonstrating that playing with other toys cannot quickly counteract the effects. The realistic children’s dolls had a neutral effect on body ideals.

Lead author Professor Lynda Boothroyd, from Durham University’s Department of Psychology, said: “Body dissatisfaction is a huge problem, particularly amongst young girls. It can have serious consequences for girls’ wellbeing and lead to eating disorders and depression.

“The results from our study indicate that playing with ultra-thin dolls, which are sold in the millions each year, could have a real negative impact on girls’ body image. This is on top of all the images of unrealistic body sizes they see on TV, in films and on social media. This is something that needs to be addressed in order to reduce the pressure on girls and women to aspire to a ‘thin ideal body’.”

The psychologists had found in previous research that the more TV we watch, the more we prefer thinner female bodies. Of the girls who took part in the study, 80% said they had ultra-thin dolls at home or with their friends, and nearly all watched films which tend to portray very thin female bodies. Dolls available in shops tend to have a projected BMI of 10 to 16 (underweight). The study used realistically proportioned dolls resembling healthy children of 7 and 9.

Dr Elizabeth Evans, from Newcastle University’s School of Psychology, said: “This study isn’t intended to make parents feel guilty about what’s in their child’s toy box, and it certainly isn’t trying to suggest that ultra-thin dolls are ‘bad’.

“What our study provides is useful information that parents can take into account when making decisions about toys. Ultra-thin dolls are part of a bigger picture of body pressures that young children experience, and awareness of these pressures is really important to help support and encourage positive body image in our children.”

The study, though small, tested the children before and after doll play, an unusual approach which nevertheless adds to growing evidence that doll play affects young girls’ beauty ideals.

Professor Martin Tovee, from Northumbria University’s Department of Psychology, said: “Our study shows how perception of ideal body size and shape is moulded from our earliest years to expect unrealistic ideals. This creates an inevitable body image dissatisfaction which is already known to lead towards disordered eating.”

Source: Medical Xpress

Journal information: Can realistic dolls protect body satisfaction in young girls?, Boothroyd et al, Body Image, 11 March 2021.