Month: February 2021

Categories : Cardiovascular Disease Diet and NutritionTags :

High GI Carbohydrates Raise CVD Risk Across Countries

On By ModernMedia

A multinational study has shown that high consumption of high glycaemic index foods increases the risk of cardiovascular disease (CVD) events such as stroke or heart disease, regardless of pre-existing CVD.

The study examined low-, middle- and high-income countries, beginning in 2006, with a median follow-up of 9.5 years. Data was used from nearly 120 000 participants.

The glycaemic index was first introduced in the 1970s to compare the rise of blood glucose from a given carbohydrate food in a patient in comparison to their blood glucose curve from the same patient ingesting glucose. This ranges from 20 for fructose to 100 for barley. In comparison to individuals eating low glycaemic index foods, those eating high glycaemic index foods had a greater risk of CVD events (51%) if there was pre-existing CVD, and even without CVD (21%). 

The highest glycaemic index foods were eaten in China, followed by Africa and Southeast Asia. The highest glycaemic loads were seen in Southeast Asia, followed by Africa and China. Glycaemic load is a better measure of a food’s effect on blood sugar taking into account how quickly it enters the bloodstream and how much glucose can be delivered.

There was less of an effect seen with glycaemic load only those with preexisting CVD showed an association between high glycaemic load diets and patient outcomes.

The participants were given a questionnaire, breaking foods down into seven categories based on glycaemic load and frequency, with a number of options each.

The broad geographic and economic scope of this study enabled the investigation of glycaemic index and load across a wide range of diets that would not be possible if it were restricted to sampling only Western-style diets.

“As expected, a higher glycaemic index was associated with an increased risk of adverse effects among the participants with a higher BMI, as reported previously,” the researchers wrote. “Although the glycaemic index of foods is independent of glucose-tolerance status, the overall postprandial glycaemic response to diet increases as the BMI increases.”

The authors acknowledge that economic development may have altered the mix of diets sampled over time, leading to an overestimation of glycaemic foods in China, for example. The findings nonetheless have important implications for primary and secondary prevention of CVD.

Source: MedPage Today

Journal information: Jenkins DJA, et al “Glycemic index, glycemic load, and cardiovascular disease and mortality” N Engl J Med 2021; DOI: 10.1056/NEJMoa2007123.

Categories : Ageing NeurologyTags :

Jump-Starting Neural Stem Cells in Aged Brains

On By ModernMedia

As we age, neural stem cells lose the ability to divide and create new neurons, resulting in a decline in memory. Now, research led by Sebastian Jessberger, a professor at the Brain Research Institute of the University of Zurich, explains why this happens.

The new neurons are used all over the brain, including the hippocampus which is responsible for memory. Declines here from age and Alzheimer’s mean fewer neurons are produced here, impacting memory functions.

“As we get older, stem cells throughout the body gradually lose their ability to proliferate. Using genetic engineering and cutting-edge microscope technology, we were able to identify a mechanism that is associated with this process,” explained doctoral candidate and first author Khadeesh bin Imtiaz. The results were published in the journal Cell Stem Cell.

The study used a mouse model to show that as organisms age, neurons’ ability to divide becomes impaired. Protein structures ensure that accumulated harmful proteins are laid out unequally among the two daughter neurons, important for the longevity of neurons. As the neurons age, the amount of nucleic proteins changes, resulting in impaired distribution of proteins, reducing the number of newly generated neurons in the brains of older mice.

The researchers identified a nuclear protein called lamin B1, levels of which decrease as people age. When lamin B1 was increased in aged mice, there was an improvement in stem cell division and the number of neurons increased.

The study was part of wider research into ageing and stem cells. “While our study was limited to brain stem cells, similar mechanisms are likely to play a key role when it comes to the ageing process of other stem cells,” said Prof Jessberger.

The latest findings represent an important step in understanding how brain stem cells change with age. “We now know that we can reactivate aging stem cells in the brain. Our hope is that these findings will one day help increase levels of neurogenesis, for example in older people or those suffering from degenerative diseases such as Alzheimer’s. Even if this may still be many years in the future,” concluded Prof Jessberger.

Source: Medical Xpress

Journal information: Cell Stem Cell, DOI: 10.1016/j.stem.2021.01.015

Categories : Diseases, Syndromes and ConditionsTags :

International Travellers at Risk of MDR Bacteria

On By ModernMedia

International travellers are at risk of picking up a number of drug-resistant pathogens, according to a new European study.

In the COVID pandemic, international travel has become a distant memory for most of those used to it. As restrictions are lifted and international travel resumes, travellers are still at risk from other dangerous pathogens. In recent years, the rise of intestinal multidrug resistant gram-negative (MDR-GN) bacteria around the world poses a serious health threat, with MDR clones of E.coli and Klebsiella pneumoniae threatening more antibiotic resistant infections around the world. The spread of MDR-GN is a known threat in long-term care facilities, with residents forming a reservoir for the microbes but is also common in international travel as well. It is well documented that international travel results in the spread of multidrug-resistant E. coli, with up to 80% of travellers returning from high-risk regions being colonised by MDR-GN bacteria for up to a year. However, the existing research only compared participants before and after travel. A group of researchers from Universities of Basel, Birmingham, Helsinki and Oslo, and the Wellcome Sanger Institute set out to investigate the spread of such bacteria on a day by day basis.

Over a period of three weeks, the researchers monitored the health of a group of European travellers in the Lao People’s Democratic Republic by analysing daily information returns and stool samples. They found that by the end of the study period, 70% of the travellers had been colonised. The bacterial strains colonised travellers staying at the same hotel and spending time in one another’s company. In one case, a participant was colonised by taking a shower in another’s bathroom.

“International travel is strongly linked to the spread of MDR-GN bacteria, with transmission highest in India and Southeast Asia, Africa and South America,” said senior study author Professor Alan McNally, University of Birmingham. “Travellers visiting these high-risk regions are at substantial risk of acquiring the bacteria. Colonisation by MDR-GN bacteria is a highly dynamic process. We found constant ‘competition’ between circulating strains acquired by individual hosts and the travelers’ ‘native’ bacteria. Travellers can pick up the bacteria even during short visits and further spread the strains after returning home.”

All of the participants had acquired extended-spectrum beta-lactamases (ESBL) during their stay in Laos. ESBL enzymes create resistance within the body to most beta-lactam antibiotics, including penicillins, cephalosporins, and aztreonam. Infections with ESBL-producing organisms have proved difficult to treat. Also, all but one participant acquired multiple strains of bacteria with 83 unique strains identified (53 E. coli, 10 Klebsiella, 20 other ESBL-GN species), with up to four other participants sharing strains.

Study co-senior author, Professor Jukka Corander, at the University of Oslo and the Wellcome Sanger Institute, commented: “Our study reveals the true scale and complexity at which drug-resistant bacteria colonise the intestinal tract during travel, demonstrating that it has been seriously underestimated previously.

“In addition, several of our participants lost some of their travel-acquired ESBL-GN strains while still abroad – indicating that previous studies solely employing pre- and post-travel sampling have under-reported the extent to which travellers are colonised by ESBL-GN.”

Source: News-Medical.Net

Journal information: Kantele, A., et al. (2021) Dynamics of intestinal multidrug-resistant bacteria colonisation contracted by visitors to a high-endemic setting: a prospective, daily, real-time sampling study. The Lancet Microbe. doi.org/10.1016/S2666-5247(20)30224-X.

Categories : Diseases, Syndromes and Conditions Expert OpinionTags :

Microbes Develop Resistance to Disinfectant Too, Warns UFS Professor

On By ModernMedia

News-Medical.Net interviewed Professor Robert Bragg of the University of the Free State on the topic of pathogens, particularly bacteria, developing resistance to common disinfectants.

Professor Robert Bragg said that the control of diseases rests on three pillars: 1) vaccinations and vaccines, 2) treatment options (such as antibiotics for bacterial diseases), and 3) biosecurity.

Proff Brage explained that 10 to 15 years ago, there was an assumption that bacteria would not evolve resistance against disinfectants, but the COVID pandemic prompted a rethink. Now, disinfectant resistance is being looked at in the same light as antibiotic resistance. Biosecurity, he said, is ensuring that individuals do not come into contact with the pathogens in the first place. This is easily seen in the COVID pandemic, where face masks are worn (with a protection against contracting the disease of up to 70%), social distancing is enforced and hands and surfaces are sanitised. Though Prof Bragg’s main area of research is not antibiotic resistance, he notes that, “There are resistance mechanisms that are shared between antibiotics and disinfectants and we are looking at how these mechanisms increase resistance to disinfectants.” 

The protection of antibiotics is something taken for granted, but although mostly easily treatable (for now), bacteria can spread much faster than viruses, which require cells to reproduce in and whose re[plication rate is measured in days. “A common well-known bacterium such as Escherichia coli has a doubling time of around 20 min under ideal conditions. In other words, it only takes just 20 minutes for a population of E. coli to go from 1 million to 2 million and another 20 mins to reach 4 million, and so on,” Prof Bragg said. In the post-antibiotic era, there would be some treatment options such as bacteriophages, but for livestock the best protection would be biosecurity. However, disinfectant resistance would reduce the effectiveness of that option.

His research team has conducted a number of studies into the mechanisms of bacterial disinfectant resistance. “My research team has been working on various aspects of efficacy and resistance to disinfectants for quite some time and we have various projects that are currently underway,” he said. “Recently we identified a highly resistant strain of a Serratia species of bacteria. This strain was substantially more resistant to many different disinfectants than the reference strain. This great difference in the levels of susceptibility has allowed us to investigate various possible research mechanisms and also to look for possible novel resistance mechanisms.”

One of his team’s discoveries was that this highly resistant bacteria strain could grow on disinfectant if it was the sole source of carbon. Other areas of research around the resistant strain include sequencing and analysis of its genome, the role of bacterial efflux pumps removing disinfectant, and the role of plasmids (vehicles of genetic transfer between bacteria) in resistance and whether they are transferrable.

With regard to viruses, there are two kinds of viruses, enveloped and naked, and disinfectant has different effects on them. Enveloped viruses such as SARS-CoV-2, have a lipid layer picked up from their host cell, and are easy to kill with simple disinfectants because they break up the lipid layer, killing the cell. Naked cells are much harder to kill, and the few disinfectants that work against them are thought to do so by somehow disrupting the virus’ receptors.

One sanitiser of concern is alcohol, where 70% is considered optimal. However, people believe that ‘more is better’, yet increasing the alcohol percentage actually makes it evaporate faster, reducing contact time and thus leaving more of the virus behind. Similarly, some sanitisers include low levels of other disinfectant substances which are below the minimum threshold to kill the pathogens. This can leave surviving bacteria to develop resistance against these other sanitisers.

Prof Bragg advised that the public should purchase and use sanitisers prudently, following their instructions for use appropriately, and preferably checking to see if they are registered. He also cautioned

Source: News-Medical.Net

Categories : Diseases, Syndromes and Conditions Paediatrics VaccinesTags :

Researchers Say New Vaccines Needed for Childhood Pneumonia

On By ModernMedia


Research in Australia on new pneumonia vaccines show that while pneumonia in children is being suppressed,  empyaema is increased.

The research, which was led by the University of New South Wales (UNSW), examined the impact of the new 13-valent pneumococcal conjugate vaccine (13vPCV) on childhood pneumonia and empyaema.
Empyaema, which is the collection of pus in the lungs, occurs in about 1% of children with pneumonia. In children, empyaema is far less fatal than it is in adults, but it does extend hospitalisation, requiring antibiotics and surgery or installation of a drain.
The findings of the study showed that while 13vPCV resulted in a 21% drop in childhood pneumonia hospitalisations, there was a contemporaneous 25% rise in empyaema hospitalisations.

According to senior author Professor Adam Jaffe, Head of the School of Women’s and Children’s Health at UNSW Medicine & Health, said the findings suggested an emergence of non-vaccine serotypes—those which 13vPCV does not cover.

13vPCV was introduced to cover the 13 most common serotypes that cause invasive pneumococcal infection, adding six more serotypes over the seven serotypes covered by its predecessor, 7cPCV.

Prof Jaffe said: “Although we found a substantial reduction in serotype 1, serotype 3 is now the predominant organism which causes childhood empyema—in 76% of cases—so, efforts must be made to create a vaccine which is more effective against serotype 3.

“In fact, Australia recently changed the vaccination dosage schedule to try and improve the effectiveness of 13vPCV against serotype 3, but we need to continue monitoring patients using molecular techniques to see if this change has had an impact.

“Childhood bacterial pneumonia and empyema are potentially preventable diseases through vaccination. So, if Australia can develop an effective vaccine, we could prevent children from being hospitalized with pneumonia and empyema.”

The researchers conducted a similar study over four years during the 7vPCV era.   

“Our new study had two parts,” Prof Jaffe said. “We analysed national hospitalisations for childhood empyaema and childhood pneumonia, then we conducted an enhanced surveillance study on children with empyaema.”

The first part of the research used publicly available hospitalisations data to find out if the introduction of 13vPCV changed how many children were admitted to hospital with pneumonia and empyaema.

The enhanced surveillance study involved the collection of blood and lung fluid samples from 401 children  with empyaema, followed by molecular testing on these samples and comparing the results to their previous study undertaken during the period of 7vPCV.

Prof Jaffe said research with a larger sample was ongoing, and 13vPCV monitoring was needed.

Source: Medical Xpress

Journal information: Roxanne Strachan et al. Assessing the impact of the 13 valent pneumococcal vaccine on childhood empyema in Australia, Thorax (2021). DOI: 10.1136/thoraxjnl-2020-216032

Categories : CancerTags :

Iron is a ‘Double-edged Sword’ For Cancer Cells

On By ModernMedia

A grant by the American Cancer society will be used to investigate the treatment of certain neuroblastoma by forcing them to overloading on iron.

Neuroblastoma is a cancer that forms in nerve tissue, and most commonly in the glands around the kidneys. It is the most frequently occurring childhood cancer that occurs outside the cranium. MYCN is overexpressed in 20-25% of neuroblastoma, and these cancers contribute to a considerable portion of paediatric cancer-related deaths. Recent research has shown that the MYCN gene introduces a weakness to ferroptosis-inducing drugs because MYCN draws on a lot of iron to help the cancer grow.  

“Iron is a double-edged sword in a cancer cell. It can help the cancer grow and survive, but it also creates these toxic molecules within the cell called reactive oxygen species,” explained Anthony Faber, PhD.

Reactive oxygen species (ROS) are unstable molecules that react with other molecules, causing DNA damage and cell death. This recently discovered form of cell death, largely influenced by iron accumulation, is called ferroptosis. Little is known about ferroptosis, and even less about cancers which may be vulnerable to ferroptosis-inducing drugs. By boosting cellular toxin removal systems, MYCN produces so much iron that it also creates a vulnerability to drugs which prevent cells from eliminating ROS. Blocking these toxin removal systems causes death among MYCN-amplified cells. 

“As MYCN continues to be one of the most important targets in cancer therapeutics, this study highlights a new and clinically important strategy for treating MYCN-associated cancers,” Dr Faber said.

“Fortunately, the Cancer Mouse Models Core run by Jennifer Koblinski, PhD, and Bin Hu, PhD, at Massey is spectacular and will allow us to robustly test these FDA-approved drugs in both patient-derived models and orthotopic models, where the tumors grow atop the adrenal glands similar to the way they grow in patients,” Dr Faber said.

If these models show positive results for the testing of these drugs, they can move on to clinical trials. He added that this study may have far reaching implications, as in certain small cell lung cancers and triple negative breast cancer, whose growth is driven c-MYC, a similar protein .

Source: Medical Xpress

Journal information: Konstantinos V. Floros et al, MYCN-amplified neuroblastoma is addicted to iron and vulnerable to inhibition of the system Xc-/glutathione axis, Cancer Research (2021). DOI: 10.1158/0008-5472.CAN-20-1641

Categories : COVID General InterestTags :

Recent Mother With COVID to Have Life Support Withdrawn

On By ModernMedia

In the UK, a comatose woman with COVID who had recently delivered her son via caesarean section should be allowed to die, a judge has ruled.

Mr Justice Hayden said that doctors should cease the woman’s life support treatment as it was no longer preserving her life but rather dragging out her death.

He said that the situation was “a tragedy of an almost unimaginable dimension” and was told there was “zero” chance of the woman making any meaningful recovery.

The woman (whose identity is withheld) was rushed to hospital a month ago while 32 weeks pregnant, after falling ill with COVID at home.

The judge was told that she had Addison’s disease, an acquired primary adrenal insufficiency from bilateral autoimmune damage to the adrenal cortex. The woman’s pancreas had ceased to function and one of her lungs had “died”, with a specialist saying that she had “essentially no normal lung function”.

The woman, who is of the Muslim faith, has a husband and a three year old son. Her husband and sister opposed the decision to withdraw life support as it was against their beliefs.

“To unplug the machine, this is for us like asking someone to kill us,” the woman’s sister said. “When God has written our death, that is when we will die.”

In an urgent court application, the judge took the case in a virtual hearing held late on Tuesday. The judge concluded that ending the woman’s life was in her best interests, adding that doctors had prepared a palliative care plan.

“This family is seeking a miracle,” he said. “This is a very young mother in circumstances of almost unspeakable sadness.”

Source: The Guardian

Categories : COVIDTags :

Ghana Receives First Vaccines from Covax

On By ModernMedia

Wednesday was a day to celebrate in Ghana as the country took delivery of the first 600 000 vaccines from the Covax inoculation scheme for poorer countries. According to the AFP, some 217 million people have been inoculated so far. 

The Covax scheme, which is led by Gavi the Vaccine Alliance, the World Health Organization and the Coalition for Epidemic Preparedness Innovations , is seeking to ensure low and middle-income countries equitably receive vaccines. head Tedros Adhanom Ghebreyesus cheered on the first delivery of the Covax vaccines with an enthusiastic tweet.

“At last!” he wrote. “A day to celebrate, but it’s just the first step.”

Healthcare experts had long been warning that global access to vaccines was necessary to put an end to the pandemic. Thus far, some 112 million people (and likely more, especially in Africa) have been infected with COVID and 2.4 million people have died from the disease. The recession has caused millions of job losses, and set back development in many areas.

The delivery of the Oxford/AstraZeneca vaccines was broadcast live on Ghanian TV, and will be administered in Ghanaian cities from Tuesday. About two billion doses are expected to be distributed this year under the Covax scheme, although it is unclear if this goal will be met, given the difficulty many advanced nations have experienced in getting vaccines. The European Union, for example, has suffered setbacks in deliveries from AstraZeneca and Pfizer. EU member nation Hungary has meanwhile decided to forge ahead with its own vaccine acquisition, ordering five million doses from Chinese firm Sinopharm, and this week began its first vaccinations.

The Ivory Coast is set to receive the next batch from Covax later this week. 

Source: Eyewitness News

Categories : Mental HealthTags :

Researchers Describe Extremist ‘Psychological Signature’

On By ModernMedia

Researchers at Cambridge University have laid out a ‘psychological signature’ for extremist behaviour.
These extremist behaviours  support violence in the name of ideology, and encompass social, political or religious attitudes. The researchers say that particular behavioural traits and unconscious cognition in the brain make certain individuals more susceptible to extremist behaviour.

These mental factors include poorer working memory and slower “perceptual strategies” (the unconscious processing of changing stimuli, eg shape and colour), and also tendencies towards impulsivity and sensation seeking.

The researchers found that social conservatism is linked to slower but more accurate unconscious decision-making, whereas liberal thinking is linked to faster but less accurate ‘perceptual strategies’.
More dogmatic people are prone to impulsivity but are slower in processing perceptual evidence.
Previous approaches to identifying radicalisation and extremism involved screening individuals by age and gender. 
“I’m interested in the role that hidden cognitive functions play in sculpting ideological thinking,” said lead author Dr Leor Zmigrod, from Cambridge’s Department of Psychology.

“Many people will know those in their communities who have become radicalised or adopted increasingly extreme political views, whether on the left or right. We want to know why particular individuals are more susceptible.”
“By examining ‘hot’ emotional cognition alongside the ‘cold’ unconscious cognition of basic information processing we can see a psychological signature for those at risk of engaging with an ideology in an extreme way,” Zmigrod said.

“Subtle difficulties with complex mental processing may subconsciously push people towards extreme doctrines that provide clearer, more defined explanations of the world, making them susceptible to toxic forms of dogmatic and authoritarian ideologies.”

 Added Zmigrod: “There appear to be hidden similarities in the minds of those most willing to take extreme measures to support their ideological doctrines. Understanding this could help us to support those individuals vulnerable to extremism, and foster social understanding across ideological divides.”
This research revisited 334 participants from a previous study where participants performed 37 cognitive tasks and were assessed on 22 personality traits. They added a further 16 tests
Demographics only weakly predicted extremist behaviour. For example, dogmatism was associated with slower perceptual ‘evidence accumulation’, and lower social risk-taking and agreeableness but greater impulsivity and ethical risk-taking. Adding the psychological signatures to demographics increased the predictive power for dogmatism from 1.53% to 23.6%. 
Political conservatism and nationalism was linked to ‘caution’ in unconscious decision-making, as well as when rewards are less valuable later, and slightly reduced strategic information processing. Personality traits for conservatism and nationalism included greater goal-directedness, impulsivity and reward sensitivity, and lower social risk-taking. For these ideologies, demographics only had a predictive power of less than 8%, but including the psychological signature boosted it to 32.5%.

In all of the ideologies examined, ‘extreme pro-group action’, including violence against others, had a similar psychological signature.

Source: Medical Xpress

Journal information:Philosophical Transactions of the Royal Society B (2021). DOI: 10.1098/rstb.2020.0424

Categories : Metabolic Disorders PaediatricsTags :

Regular Sleep Patterns in Toddlers Important for BMI

On By ModernMedia

Although getting regular sleep patterns in toddlers has long been a priority for parents, researchers have shown it is important for toddlers’ BMI.

The researchers, led by Lauren Covington, an assistant professor in the University of Delaware School of Nursing, investigated the link between poverty, regular sleep patterns and BMI in toddlers. According to The National Sleep Foundation, toddlers 1- to 3-years-old should have 12 to 14 hours of sleep in a 24-hour period.

“We’ve known for a while that physical activity and diet quality are very strong predictors of weight and BMI,” said Prof Covington, the lead author of the article. “I think it’s really highlighting that sleep may be playing a bigger role here than it’s been given credit for.”

The researchers aimed to investigate the relationship between poverty and BMI in toddlers, and wanted to see whether sleep behaviour, activity or food intake could provide the explanation.

Using data from families in an obesity prevention trial, 70% of whom were below the poverty line, and all eligible for nutritional supplementation grants, Toddlers were given accelerometers to wear to measure physical activity and parents filled out food diaries.

The researchers found that children from households with greater poverty were more likely to have greater inconsistent bedtimes, and those with more inconsistent bedtimes had higher BMI percentages.

Prof Covington said this is likely to be a bidirectional relationship. “There’s a lot of teasing out the relationships of the mechanisms that are at play here, which is really difficult to do because I think they’re all influencing each other,” she said.

Having consistent bedtimes where children go to bed within one hour of the normal time is a recommended guideline, but for families in poverty this may be impossible for a variety of reasons. Single parent households and juggling multiple jobs are part of the challenges they face.

“Implementing a consistent bedtime could be one behavioural change that a family could potentially do,” said Prof Covington. “It’s more attainable than maybe getting healthy food at the grocery store or playing outside on the playground, especially now with the cold weather. Just having a consistent bedtime can help provide some sense of structure, but then maybe have better implications for health and BMI as well.”

Source: Medical Xpress

Journal information: Lauren Covington et al. Longitudinal Associations Among Diet Quality, Physical Activity and Sleep Onset Consistency With Body Mass Index z-Score Among Toddlers in Low-income Families, Annals of Behavioral Medicine (2020). DOI: 10.1093/abm/kaaa100