Public Health Archives - Page 10 of 52 - Dr Amin Azhari

Infant Immune Systems Are Stronger Than You Think

New study may help explain why infants are less affected by COVID than adults. The infant immune system has a reputation for being weak and underdeveloped when compared to the adult immune system, but the comparison isn’t quite fair.

Babies do get a lot of respiratory illnesses from viruses, like influenza and respiratory syncytial virus, compared to adults. But unlike adults, babies are seeing these viruses for the first time. “Adults don’t get sick as often because we’ve recorded memories of these viruse, and the memories protect us,” Farber says, “whereas everything the baby encounters is new to them.”

The paper, titled “Infant T cells are developmentally adapted for robust lung immune responses through enhanced T cell receptor signaling(link is external and opens in a new window),” was published in Science Immunology.

Release date: 10 December 2021
Source: Columbia University Irving Medical Center

Triggers of stroke: anger, emotional upset, and heavy physical exertion

global study co-led by NUI Galway into causes of stroke has found that one in 11 survivors experienced a period of anger or upset in the one hour leading up to it. One in 20 patients had engaged in heavy physical exertion.

The suspected triggers have been identified as part of the global INTERSTROKE study – the largest research project of its kind, which analysed 13,462 cases of acute stroke, involving patients with a range of ethnic backgrounds in 32 countries, including Ireland.

Stroke prevention is a priority for physicians, and despite advances it remains difficult to predict when a stroke will occur. Many studies have focused on medium to long-term exposures, such as hypertension, obesity or smoking. Our study aimed to look at acute exposures that may act as triggers.

The research analysed patterns in patients who suffered ischemic stroke – the most common type of stroke, which occurs when a blood clot blocks or narrows an artery leading to the brain, and also intracerebral haemorrhage – which is less common and involves bleeding within the brain tissue itself.

The research has been published in the European Heart Journal.

Release date: 03 December 2021
Source: National University of Ireland Galway

Neurologic disorders, Public Health

ALS therapy should target brain, not just spine

The brain is indeed a target for treating ALS (amyotrophic lateral sclerosis), Northwestern Medicine scientists have discovered. This flips a long-standing belief that the disease starts in the spinal motor neurons and any therapy would need to target the spine as the key focus.

A new Northwestern study shows the degeneration of brain motor neurons (the nerve cells in the brain that control movement of the limbs) is not merely a byproduct of the spinal motor neuron degeneration, as had been previously thought. The study was conducted in two mouse models of ALS that represent 90% of all ALS pathologies.

ALS is a swift and fatal neurodegenerative disease that paralyzes its victims.

Upper motor neuron diseases, such as ALS, hereditary spastic paraplegia and primary lateral sclerosis affect more than 250,000 people a year in the U.S. alone. There is no cure and no effective long-term treatment strategy.

This is the first study to clearly reveal the brain motor neuron degeneration is not a consequence of spinal motor neuron degeneration but is independent of the spinal motor neuron degeneration.

The research also is the first to show that the gene UCHL1 is important for maintaining the health of brain motor neurons that are diseased due to two independent underlying causes. One is the accumulation of badly folded proteins and the other is the accumulation of sticky protein clumps inside the cells. These problems are observed in more than 90% of all ALS cases and also in other cases of upper motor neuron diseases.

Northwestern University scientists have previously identified NU-9, the first experimental compound that eliminates the ongoing degeneration of upper motor neurons that become diseased and are a key contributor to ALS. Now, this study reveals the importance and significance of treating upper motor neurons in ALS and identifies the first genetic target.

The next step is to determine the best dose and the best site of injection with respect to improvement of movement and reduction of disease conditions in at least two different ALS disease models. After preclinical toxicology studies, scientists will move to translate these results into a clinical trial, a process that likely will take several years.

The paper was published Dec. 2 in Nature Gene Therapy.

Release date: 03 December 2021
Source: Northwestern University

Public Health

HOW REGULAR EXERCISE CAN PROTECT AGAINST FATTY LIVER ASSOCIATED DISEASES

Worldwide one in four persons suffers from non-alcoholic liver disease (NAFLD, also called metabolic liver disease MAFLD). Those affected often have type 2 diabetes as well as an increased risk of liver cirrhosis and cardiovascular diseases. In addition, NAFLD is associated with increased mortality. An imbalance between energy intake and consumption is discussed as a cause for the disease. This leads to fat deposits in the liver and over time impairs the function of the mitochondria * – both risk factors for the development of hepatic insulin resistance and liver inflammation.

How exercise modifies the adaptation of the liver to increased energy intake
To prevent and treat NAFLD, lifestyle modification with increased physical activity is recommended. To what extent regular exercise alters the adaptation of the liver to increased energy intake and what role skeletal muscle plays in this process was investigated by scientists at the Institute of Clinical Chemistry and Pathobiochemistry at Tübingen University Hospital and at the Institute of Diabetes Research and Metabolic Diseases (IDM) of Helmholtz Munich at the University of Tübingen. The researchers collaborated with the Institute of Experimental Genetics (IEG) at Helmholtz Munich, the Leibniz Institute for Analytical Sciences in Dortmund, and the Dalian Institute of Chemical Physics in China.

Original publication:
Hoene, M. et al.: Exercise prevents fatty liver by modifying the compensatory response of mitochondrial metabolism to excess substrate availability. Molecular Metabolism.
Release date: 20 December 2021
Source: Deutsches Zentrum fuer Diabetesforschung DZD

Public Health

Ultrasound could be used to treat psychiatric disorders

Imagine passing an exam, and thinking your success was down to the socks you wore or the number of biscuits you’d eaten, rather than the hours of study you’d put in.

This is an issue of ‘credit assignment’, where a person or animal attributes the wrong outcome to an event, exists in a variety of psychiatric disorders, like addiction or OCD where people still believe that drug consumption on engaging in certain rituals will lead to positive outcomes.

Now a new study in macaque monkeys has shed light on which parts of the brain support credit assignment processes and, for the first time, how low-intensity transcranial ultrasound stimulation (TUS) can modulate both brain activity and behaviours related to these credit assignment processes.

While currently developed in an animal model, this line of research and the use of TUS could one day be applied to clinical research to tackle psychiatric conditions where maladaptive decisions are observed.

After stimulating this brain area, the animals in the study became more exploratory in their decisions. As a consequence of the ultrasound neuromodulation, behaviour was no longer guided by choice value – meaning that they could not understand that some choices would cause better outcomes – and decision-making was less adaptive in the task.

The study also showed that this process remained intact if another brain region (also part of the prefrontal cortex) was stimulated; showing for the first time how task-related brain modulation is specific to stimulation of areas that mediate a certain cognitive process.

The full study, entitled Ultrasound modulation of macaque prefrontal cortex selectively alters credit assignment–related activity and behaviour is available to view in the journal Science Advances.

Release date: 16 December 2021
Source: University of Plymouth

Neurologic disorders, Public Health

Greater Exposure to Nitrogen Dioxide Linked to Higher Levels of Biomarkers of Alzheimer Disease in the Brain

A study has found an association between air pollution and higher levels of deposition of beta-amyloid protein in the brain and of neurofilament light (NfL) in cerebrospinal fluid.

Investigators from the Barcelonaβeta Brain Research Center (BBRC), the research arm of the Pasqual Maragall Foundation, in collaboration with ISGlobal, have found an association between exposure to air pollution and higher levels of biomarkers of Alzheimer’s disease, particularly in individuals with elevated beta-amyloid deposition in the brain. The results of the study, which was supported by the ”la Caixa” Foundation, have been published in Environment International.

Release date: 16 December 2021
Source: Barcelona Institute for Global Health (ISGlobal)

Covid-19, Public Health

Drug could more effectively treat patients hospitalised with COVID-19 pneumonia

A proof-of-concept trial led by the University of Birmingham and University Hospitals Birmingham NHS Foundation Trust has identified a drug that may benefit some patients hospitalised with COVID-19 pneumonia.

An antibody already in late-stage trials to treat rheumatoid arthritis, namilumab targets a ‘cytokine’ which is naturally secreted by immune cells in the body but, in uncontrolled levels, is believed to be a key driver of the excessive and dangerous lung inflammation seen in COVID-19 patients.

The trial, carried out in collaboration with the University of Oxford and funded by the Medical Research Council and carried out between June 2020 and February 2021, involved patients aged over 16 with COVID-19 pneumonia either being treated on a ward or Intensive Care Unit (ICU) at nine NHS hospitals across the UK.

The study, published in The Lancet Respiratory Medicine, involved 54 patients receiving ‘usual care’ (steroids and oxygen or ventilation, depending on the severity of disease) and 57 patients given usual care as well as a single intravenous dose of 150mg of namilumab.

As well as COVID-19 pneumonia, all study participants had CRP levels greater than 40mg/l. The researchers compared the probability of the reduction of levels of CRP in patients. Compared to usual care alone, the researchers found there was a 97% probability of CRP being reduced over time in those given namilumab when compared with usual care alone.

The patients were monitored, and after 28 days the study also showed there were fewer deaths and more discharges from hospital or ICU in those who had been given namilumab compared to those receiving usual care alone.

By day 28, 78% (43) of the patients receiving namilumab were discharged from hospital or ICU, compared to 61% (33) of the patients given usual care. In the namilumab group, 11% (6) were still in hospital by day 28, compared to 20% (11) in the usual care group. Of those in the namilumab group, 11% (6) patients died compared to 19% (10) who died in the usual care group by day 28.

The team calculated the differences between the two cohorts in overall probability of those being discharged from ICU or a ward at 28 days. Of those on a ward, the probability of discharge at day 28 was 64% in the usual care cohort, compared to 77% in the Namilumab cohort. Of those in ICU, probability of discharge at day 28 was 47% in the usual care group, compared to 66% in the Namilumab cohort.

Release date: 17 December 2021
Source: University of Birmingham

Covid-19, Neurologic disorders, Public Health

SARS-CoV-2 protein interacts with Parkinson’s protein, promotes amyloid formation

Case reports of relatively young COVID-19 patients who developed Parkinson’s disease within weeks of contracting the virus have led scientists to wonder if there could be a link between the two conditions. Now, researchers reporting in ACS Chemical Neuroscience have shown that, at least in the test tube, the SARS-CoV-2 N-protein interacts with a neuronal protein called α-synuclein and speeds the formation of amyloid fibrils, pathological protein bundles that have been implicated in Parkinson’s disease.

In addition to respiratory symptoms, SARS-CoV-2 can cause neurological problems, such as loss of smell, headaches and “brain fog.” However, whether these symptoms are caused by the virus entering the brain, or whether the symptoms are instead caused by chemical signals released in the brain by the immune system in response to the virus, is still controversial. In Parkinson’s disease, a protein called α-synuclein forms abnormal amyloid fibrils, leading to the death of dopamine-producing neurons in the brain. Interestingly, loss of smell is a common premotor symptom in Parkinson’s disease. This fact, as well as case reports of Parkinson’s in COVID-19 patients, made Christian Blum, Mireille Claessens and colleagues wonder whether protein components of SARS-CoV-2 could trigger the aggregation of α-synuclein into amyloid. They chose to study the two most abundant proteins of the virus: the spike (S-) protein that helps SARS-CoV-2 enter cells, and the nucleocapsid (N-) protein that encapsulates the RNA genome inside the virus.

Release date: 14 December 2021
Source: American Chemical Society

Public Health

Specific components of air pollution identified as more harmful than others

Ammonium is one of the specific components of fine particulate matter (PM2.5), that has been linked to a higher risk of death compared to other chemicals found in it, according to a new study in the journal Epidemiology.

Particulate matter is one of the most dangerous air pollutants – a complex mixture of extremely small particles and liquid droplets which can be directly emitted from natural sources, such as forest fires, or when gases emitted from power plants, industries and automobiles react in the air.

PM2.5 is airborne particulate matter smaller than 2.5 µm in diameter. It is usually believed the black carbon part of PM2.5 (mainly stemming from motorised vehicles) was the most harmful one. However, the team’s analysis of data in 210 cities across 16 countries from 1999-2017 found human health risks from air pollution vary depending on the proportion of different components in PM2.5.

One of the most dangerous components is ammonium (NH4+), originating mostly from fertiliser use and livestock. The risk of excess mortality from PM2.5 roughly increased from 0.6% to 1% when the proportion of ammonium increased from 1% to 20% in the mix1.

Cities with a larger concentration of ammonium in the mix, including Japanese cities Aikita, Aomori, Sendai, and Canadian cities London Ontario and Sarnia were associated with higher health risks. Specific action aimed at the agricultural and farming sectors may speed up the reduction of the negative health impacts of air pollution.

Release date: 16 December 2021
Source: London School of Hygiene & Tropical Medicine

Public Health

Antibiotics Can Be First-Line Therapy for Uncomplicated Appendicitis Cases

With numerous recent studies demonstrating that antibiotics work as well as surgery for most uncomplicated appendicitis cases, the non-surgical approach can now be considered a routine option, according to a review article in JAMA.

“Acute appendicitis is the most common abdominal surgical emergency in the world, striking about one in 1,000 adults,” Pappas said. “Until recently, the only treatment option was surgery, so having a non-surgical approach for many of these cases has significant impact for both patients and the health care system.”

Pappas said the criteria for determining the best treatment approach is nuanced, but not excessively difficult. Appendicitis cases — marked by abdominal pain that often migrates to the lower right side, nausea and vomiting, and low-grade fever – are confirmed with ultrasound and/or CT scans.

Release date: 14 December 2021
Source: Duke University Medical Center