Tag: 25/4/22

Categories : COVIDTags :

Long COVID May be Due to Suppressed Immune System

On By ModernMedia
Man wearing mask with headache
Source: Usman Yousaf on Unsplash

Scientists studying the effect of the monoclonal antibody Leronlimab on long COVID may have found a surprising clue to the baffling syndrome, one that contradicts their initial hypothesis. The cause may be down to an abnormally suppressed immune system, and not a persistently hyperactive one as they initially suspected.

The study was published in Clinical Infectious Diseases.

“While this was a small pilot study, it does suggest that some people with long COVID may actually have under-active immune systems after recovering from COVID, which means that boosting immunity in those individuals could be a treatment,” said senior author Professor Otto Yang.

COVID is known to be caused by hyperactive immune responses against SARS-CoV-2 resulting in damage to lungs and other organs, and sometimes a cytokine storm that overwhelms the individual, which could lead to severe illness and death.

For some who recover from COVID, various symptoms can persist for months, such as fatigue, mental haziness, and shortness of breath. Classified as long COVID, a limited understanding of the causes makes it difficult to develop treatments.

One suggested possibility is that persistence of immune hyperactivity after COVID is a major contributor. The researchers therefore ran a small exploratory trial of Leronlimab, an antibody that attaches to an immune receptor called CCR5 that is involved in inflammation, on 55 people with the syndrome. Leronlimab was originally being developed as an HIV treatment.

Participants were randomised to receiving either weekly injections of the antibody or a saline placebo for eight weeks, and changes in 24 symptoms associated with long COVID were tracked, including loss of smell and taste, muscle and joint pain, and brain fog.

Originally, the researchers believed that blocking CCR5 would calm an overactive immune system after COVID infection. Indeed, preliminary results from an earlier trial appeared to show an improvement with Leronlimab.

“But we found just the opposite,” Prof Yang said. “Patients who improved were those who started with low CCR5 on their T cells, suggesting their immune system was less active than normal, and levels of CCR5 actually increased in people who improved. This leads to the new hypothesis that long COVID in some persons is related to the immune system being suppressed and not hyperactive, and that while blocking its activity, the antibody can stabilize CCR5 expression on the cell surface leading to upregulation of other immune receptors or functions.”

The findings, the researchers wrote, “suggests a complex role for CCR5 in balancing inflammatory and anti-inflammatory effects, eg through T regulatory cells,” although the results need to be confirmed in a larger, more definitive study.

Source: University of California – Los Angeles Health Sciences

Categories : Diet and NutritionTags :

Dentures Could Worsen Nutritional Intake

On By ModernMedia
Dentist checking teeth
Image by Caroline LM on Unsplash

Dentures could potentially worsen a person’s nutritional intake, according to new research in the Journal of Prosthodontics. The research team examined electronic dental and health records to gain a better understanding of how oral health treatments affect individuals’ overall health over time.

This is first known study to link lab values of nutritional biomarkers to dental records.

Thankam Thyvalikakath, DMD, MDS, PhD, senior author, explained the impact of dentures. “Dentures are a significant change for a person. They do not provide the same chewing efficiency, which may alter eating habits. Dentists need to be aware of this and provide advice or a referral for nutrition counselling. These patients need support during the transition and possible continued monitoring.”

The researchers matched the dental records of more than 10 000 patients which included lab test data, including malnutrition markers. The data included complete blood count, basic metabolic profile and lipid and thyroid panel tests. Comparing the lab results from two years before a patient received dentures to the two years after, the researchers found that people with dentures had a significant decline in certain nutrition markers over those two years.

People who did not wear dentures did not experience this decline. While marker levels were still within normal range, but the levels could potentially fall as more time passes, and the researchers urged dentists to be aware of this possibility.

Future research will look at other factors that may influence nutrition, including insurance status and dental clinic characteristics.

Source: Regenstrief Institute

Categories : General InterestTags :

Message Boards Showing Highway Death Toll Cause More Crashes

On By ModernMedia
Driver at the wheel of a car
Photo by Why Kei on Unsplash

Displaying the highway death toll on message boards (eg, “1669 deaths this year on Texas roads”) is a common awareness campaign, but new research published in Science shows that it actually leads to more crashes.

Their study focuses on Texas, where officials chose to display these messages only one week each month. The researchers compared crash data from before the campaign to after it started as well as examined the weekly differences within each month during the campaign. They found:

  • There were more crashes during the week with fatality messaging compared to weeks without.
  • Displaying a fatality message caused a 4.5% in crashes in the 10km after the message boards. This increase is comparable to raising the speed limit 5–8kph or reducing highway police by 6–14%, according to previous research.
  • The researchers suggest this “in-your-face” messaging approach weighs down drivers’ “cognitive loads,” temporarily impacting their ability to respond to changes in traffic conditions.

“Driving on a busy highway [and] having to navigate lane changes is more cognitively demanding than driving down a straight stretch of empty highway,” said Assistant Professor Joshua Madsen. “People have limited attention. When a driver’s cognitive load is already maxed out, adding on an attention-grabbing, sobering reminder of highway deaths [can] become a dangerous distraction.”

Another finding was that the higher the number in the fatality message, the more harmful the effects. The number of additional crashes each month increased as the death toll accumulated throughout the year, with the most additional crashes occurring in January when the message stated the year’s total. Crashes were also found to increase in areas where drivers experienced higher cognitive loads, such as heavy traffic or driving past multiple message boards.

“The messages also increased the number of multi-vehicle crashes, but not single-vehicle crashes,” said Hall. “This is in line with drivers with increased cognitive loads making smaller errors due to distraction, like drifting out of a lane, rather than driving off the road.”

However, crashes were reduced when the displayed death tolls were low and when the message appeared where the highways were less complex. Madsen said this suggests that at times the messaging was not as taxing on drivers’ attention. However, alternative campaigns should be considered.

“Distracted driving is dangerous driving,” said Madsen. “Perhaps these campaigns can be reimagined to reach drivers in a safer way, such as when they are stopped at an intersection, so that their attention while driving remains focused on the roads.”

Source: University of Minnesota

Categories : Hospitals Medical Research & TechnologyTags :

The Pros and Cons of Robotics in Healthcare

On By ModernMedia
Photo by Alex Knight on Unsplash

Having to cope with the strain of COVID on an already fragile healthcare system, a few hospitals in the Western Cape have been introducing robotics for specialised tasks – but are they worth the hype?

Robotics was able to fill an unprecedented need during the COVID pandemic – the ability to remotely conduct ward rounds from remote locations. Tygerberg Hospital made use of ‘Quintin’, a robot that is essentially a tablet on a mobile stand that allows users to remotely communicate and inspect the area, but it can’t physically interact with its environment.

Robotics offers greater surgical precision, which may translate into reduced healthcare load. IOL reported that the provincial Department of Health plans to use a pair of new robotic surgery machines installed at the Groote Schuur and Tygerberg hospitals to fast-track surgeries and address the province’s surgical backlogs caused by COVID. These robotic surgery units will be used for procedures on colorectal, liver, prostate, kidney and bladder cancers, and women with severe endometriosis. In the province’s private sector, Netcare Christiaan Barnard Memorial Hospital also makes use of robotic-assisted surgery.

Robotic surgery has a number of advantages. The small robotic arms allow for smaller incisions and faster recovery times, reducing the strain on hospitals. A liver resection that would have a patient in hospital for a week can be reduced to one or two days with robotic surgery. More complex surgery becomes possible, eg in difficult to access areas or in patients with obesity. Robotic surgery allows surgeons to be off their feet, easing an extremely fatiguing job, and the software automatically compensates for any tremor in the surgeon’s hands.

However, robotic surgery still has drawbacks – chief among them is cost and the need to have trained personnel to operate them. There is also some latency between the surgeon’s hands movements and the corresponding movement of the robot, leading to possible errors. Shorting of the electrical current running through the robotic arms can also cause burns to the patient’s tissue, and there is also the possibility of nerve compression injuries due to the positioning of the patient. Furthermore, operator errors, especially when operators are inexperienced or robotic surgery is performed in lower volumes, is always a possibility.

Robotics have promising applications in sanitation – they can easily disinfect areas using UV light, for example – and can also assist nurses with certain tasks, such as making a 3D vein map prior to a venipuncture. Some robots can even assist the elderly, conversing with them and can perform simple tasks like calling a nurse. Other applications include the much simpler technology of exoskeletons, a wearable frame which amplify users’ strength (though nowhere near that of the fictional Iron Man) and are useful in rehabilitation and for enhancing mobility in the elderly. Other applications include increasing strength of care staff for assisting patients, freeing up other staff.

Some exoskeletons are even purely mechanical, merely readjusting loads without any sophisticated electronics or motors. Yet even these are prohibitively expensive: the Phoenix Medical Exoskeleton goes for about US$30 000 each.

While promising, robotic systems are at present still hugely expensive, limited in function and can only assist with a small fraction of the tasks that healthcare workers perform. Even if the cost could be reduced enough to help ease healthcare worker burden in South Africa to help, that still leaves the problem of enough experienced and motivated healthcare workers, beds and neglected rural areas.

Categories : ExerciseTags :

When Dieting, High-intensity Exercise Might Combat Cravings

On By ModernMedia
Tired woman after exercise
Photo by Ketut Subiyanto on Pexels

Revealing another benefit of exercise for weight loss, results from a study published in Obesity showed that rats on a 30-day diet who exercised intensely were better able to resist cues for favoured, high-fat food pellets.

The experiment was designed to investigate a phenomenon called “incubation of craving”, where the longer a desired substance is denied, the harder it is to resist cue for it. The findings suggest that exercise modulated how hard the rats were willing to work for cues associated with the pellets, reflecting how much they craved them.

Though more researcher is needed, these findings show that exercise may shore up restraint when it comes to certain foods, explained corresponding author Travis Brown, a physiology and neuroscience researcher at Washington State University.

“A really important part of maintaining a diet is to have some brain power – the ability to say ‘no, I may be craving that, but I’m going to abstain,'” said Brown. “Exercise could not only be beneficial physically for weight loss but also mentally to gain control over cravings for unhealthy foods.”

The researchers trained 28 rats to press a lever that turned on a light and made a tone before dispensing a high-fat pellet. After the training period, they tested to see how many times the rats would press the lever just to get the light and tone cue.

The rats where then split up into two groups. One underwent a regime of high-intensity treadmill running while the other had no additional exercise outside of their regular activity. Both sets of rats were denied access to the high-fat pellets for 30 days. At the end of that period, the researchers gave the rats access to the levers that once dispensed the pellets again, but this time the levers only gave the light and tone cue when pressed. The animals that did not get exercise pressed the levers significantly more than rats that had exercised, indicating that exercise lessened the craving for the pellets.

In future studies, the research team plans to investigate the effect of different levels of exercise on this type of craving as well as how exactly exercise works in the brain to curb the desire for unhealthy foods.

Though this is a novel study, Brown said it builds on earlier work that first defined the term “incubation of craving“. Brown also gave credit to research showing that exercise can blunt cravings for cocaine.

Whether food can be addictive in the same way as drugs can is a still a question for research. Not all foods have the same effect – as Brown pointed out, “no one binge eats broccoli.” However, people do seem to respond to cues, such as fast-food ads, encouraging them to eat foods high in fat or sugar, and those cues may be harder to resist the longer they diet.

Being able to disregard these signals could be yet another way exercise enhances health, Brown said.

“Exercise is beneficial from a number of perspectives: it helps with cardiac disease, obesity and diabetes; it might also help with the ability to avoid some of these maladaptive foods,” he said. “We’re always looking for this magic pill in some ways, and exercise is right in front of us with all these benefits.”

Source: Washington State University