Microwave data assimilation improves forecasts of hurricane intensity, rainfall

 In 2017, Hurricane Harvey stalled after making landfall over coastal Texas, pouring down record rainfall, flooding communities and becoming one of the wettest and most destructive storms in United States history. A new technique using readily available data reduces forecast errors and could improve track, intensity and rainfall forecasts for future storms like Hurricane Harvey, according to Penn State scientists.

"Our study indicates that avenues exist for producing more accurate forecasts for tropical cyclones using available yet underutilized data," said Yunji Zhang, assistant research professor in the Department of Meteorology and Atmospheric Science at Penn State. "This could lead to better warnings and preparedness for tropical cyclone-associated hazards in the future."

Adding microwave data collected by low-Earth-orbiting satellites to existing computer weather forecast models showed improvements in forecasting storm track, intensity and rainfall when using Hurricane Harvey as a case-study, the scientists said.

"Over the ocean, we don't have other kinds of observations underneath the cloud tops to tell us where eyewalls are, where the strongest convections are, and how many rain or snow particles there are in those regions, except for occasional reconnaissance aircraft that fly into some of hurricanes," Zhang said. "This is very important for later predictions of how intense storms will be or how much rainfall hurricanes will bring."

The research builds on the team's prior work that improved hurricane forecasts using data assimilation, a statistical method that aims to paint the most accurate picture of current weather conditions, important because even small changes in the atmosphere can lead to large discrepancies in forecasts over time.

In the prior work, scientists with Penn State's Center for Advanced Data Assimilation and Predictability Techniques assimilated infrared brightness temperature data from the U.S. Geostationary Operational Environmental Satellite, GOES-16. Brightness temperatures show how much radiation is emitted by objects on Earth and in the atmosphere, and the scientists used infrared brightness temperatures at different frequencies to paint a better picture of atmospheric water vapor and cloud formation.

But infrared sensors only capture what is happening at the cloud tops. Microwave sensors view an entire vertical column, offering new insight into what is happening underneath clouds after storms have formed, the scientists said.

"This is especially important when a hurricane matures in later stages of development, when pronounced and coherent cloud structures exist and you can't see what's going on underneath them," Zhang said. "That's the time when hurricanes are most dangerous because they're very strong and sometimes already approaching landfall and threatening people. That's when the microwave data are going to provide the most valuable information."

Combining assimilated infrared and microwave data reduced forecast errors in track, rapid intensification and peak intensity compared to infrared radiation alone for Hurricane Harvey, the researchers reported in the journal Geophysical Research Letters. They said assimilating both sets of data resulted in a 24-hour increase in forecast lead-time for the rapid intensification of the storm, a critical time when some storms quickly gain strength.

Assimilating the microwave data also led to a better understanding of the amount of water particles in the storm and more accurate rainfall totals for Harvey, the scientists said.

"Rainfall predictions are extremely critical for preparing the public for hazards and evacuations," Zhang said. "If we have a better understanding of how many rainfall particles there are in the storm, we have a higher likelihood of more accurate forecasts of how much rainfall there will be. Based on that, we will have more advanced guidance on how people should react."

The scientists said additional work is needed to improve the model's microphysics to simulate water and ice particles more realistically.

This study is based on work by former Penn State Distinguished Professor Fuqing Zhang, who led the project at the time of his unexpected death in July 2019.

"When our dear friend and colleague Fuqing Zhang died, the thread of ideas that wove together our ongoing combined infrared and microwave radiance data assimilation experiments unraveled," said Eugene Clothiaux, professor of meteorology and atmospheric science and a co-author of the paper. "We came together over an extended period of time to reassemble the thread as best as possible."

Also contributing from Penn State were Steven Greybush, associate professor; Xingchao Chen, assistant professor; and Man-Yau Chan, Christopher Hartman and Zhu Yao, graduate students.

Several former Penn State doctoral students, postdocs and faculty also contributed: Scott Sieron, support scientist at I.M. Systems Group; Yinghui Lu, associate professor at Nanjing University in China; Robert Nystrom, postdoc at the National Center for Atmospheric Research; Masashi Minamide, assistant professor at the University of Tokyo; James Ruppert, assistant professor at the University of Oklahoma; and Atsushi Okazaki, assistant professor at Hirosaki University in Japan.

The National Science Foundation, NASA, the National Oceanic and Atmospheric Administration and the Department of Energy Biological and Environmental Research program supported this work.

Source: ScienceDaily

Suffering from psoriasis? Blame this trio of proteins

 About 7.5 million Americans suffer from psoriasis, an autoimmune disease that shows up as patches of red, inflamed skin and painful, scaly rashes. Although there are effective treatments for psoriasis, not everyone responds to these therapies -- and for many, the relief is temporary.

"These therapies don't reduce disease by 100 percent, and they don't cure the disease" says La Jolla Institute for Immunology (LJI) Professor Michael Croft, Ph.D. "And if you take patients off those drugs, the disease almost always comes back."

Now Croft and his team in LJI's Center for Autoimmunity and Inflammation have discovered how a key protein called TWEAK damages skin cells in psoriasis patients. Their findings, in mice and with human skin cells, suggest targeting TWEAK may help control the disease

"We think TWEAK might be considered a potential target for the treatment of psoriasis," says Rinkesh Gupta, Ph.D., a postdoctoral fellow at LJI and first author of the new Science Immunology study. "It's good to have this chance to develop a new therapeutic option."

The findings build on the Croft Lab's previous work showing that TWEAK can interact with the most common type of skin cell, called a keratinocyte. By investigating TWEAK-deficient mice, the researchers found that TWEAK is a driver of inflammation in a model of psoriasis.

The new study shows that TWEAK does not work alone. By studying human keratinocytes, the researchers discovered that TWEAK teams up with two other proteins, called tumor necrosis factor (TNF) and interleukin-17 (IL-17), to trigger inflammation. This trio appears to control the production of inflammatory molecules and the expression of additional inflammation-associated proteins in patients with psoriasis.

"The fact that they work together suggests the disease is essentially driven by all three of those particular proteins at the same time," says Croft. "The primary implication is that TWEAK will also be a good drug target. as has already been proven for TNF and IL-17."

To test this, the researchers used a mouse model of psoriasis to compare how well a TWEAK-inhibitor measured up to therapies inhibiting IL-17 or TNF.

The results suggest the team is on the right track. "If you inhibit TWEAK from working on its receptor on keratinocytes, you get the same therapeutic effect as when you inhibit TNF or IL-17," says Gupta. This finding is especially encouraging because TNF and IL-17 are both FDA-approved drug targets for psoriasis.

Although human clinical trials remain to be done, Croft sees a future for TWEAK inhibitors as therapies for many types of skin diseases. "We think TWEAK is involved in skin inflammation in general," says Croft.

His lab is now investigating the role of TWEAK in atopic dermatitis, also called eczema, a very common type of skin inflammation, especially in babies and young children. Croft says while psoriasis and atopic dermatitis are distinct diseases, they do have a few things in common -- and there are not as many good treatments for atopic dermatitis.

"There's certainly a lot of room for improvement in treatment of atopic dermatitis patients," he says.

The study, "TWEAK functions with TNF and IL-17 on keratinocytes and is a potential target for psoriasis therapy," was supported by the National Institutes of Health (grant AR072640).

Additional study authors include Donald T. Gracias, Daniela Salgado Figueroa, Haruka Miki, Jacqueline Miller, Kai Fung, Ferhat Ay and Linda Burkly.

Source: ScienceDaily

COVID-19: Does Omicron cause less damage to the lungs?

 

• Animal studies and experiments involving cells cultured in the laboratory suggest that the Omicron variant may have a reduced ability to infect the lungs, compared with the Delta variant.
• This could explain why the Omicron variant appears to cause less severe disease than the Delta variant.
• These studies indicate that the Omicron variant could be more efficient at infecting the upper airways than the Delta variant, potentially explaining its increased contagiousness.
• The ability of the Omicron variant to escape neutralizing antibodies may also be responsible for its increased transmissibility.

Early reports following the emergence of the Omicron variant suggest that the variant is more likely to cause less severe illness than previous variants of SARS-CoV-2.

Sequencing of the Omicron genome suggested that this variant carries a large number of mutations, including on the spike protein. The large number of mutations carried by Omicron could be a potential reason for this reduction in illness severity.

However, the milder disease due to an Omicron infection could also be a result of a person’s enhanced immunity, acquired due to vaccination or past SARS-CoV-2 infections.

Although an increase in immunity may influence the severity of illness, studies in animals and cells cultured in the laboratory suggest that the mutations carried by the Omicron variant have made it less efficient at infecting the lungs than the Delta variant. This could explain the less severe illness that the Omicron variant causes.

Laboratory and animal studies

The SARS-CoV-2 virus can affect both the upper and lower respiratory tracts. The upper respiratory tract consists of the nose, sinuses, and throat, whereas the lower respiratory tract includes the trachea and the lungs.

Mild illness or early SARS-CoV-2 infections are likely to involve upper respiratory tract symptoms, such as a runny nose and sore throat.

Severe illness due to the wild-type SARS-CoV-2 and the previous variants oftenTrusted Source involves the infection and inflammation of the lungs.

Inflammation can cause fluid to accumulate in the air sacs, or alveoli, in the lungs, reducing the capacity of the lungs to transfer oxygen to the blood.

Scientists have conducted experiments using animal models and laboratory cultures of lung cells to characterize the ability of Omicron to infect the respiratory tract and cause severe illness.

This includes a study carried out at the University of Hong Kong that used human lung cells cultured in the laboratory, to analyze the ability of the Omicron variant to infect the lungs. These cells were cultured from lung tissue removed during treatment of the lung. Typically, this tissue is discarded.

In the study, Omicron replicated 70 times faster than Delta in the human bronchi, which are the tubes connecting the trachea with the lungs. However, it was less efficient at replicating in the lung tissue than Delta and the wild-type SARS-CoV-2.

Other research groups have compared the ability of the Omicron, Delta, and other SARS-CoV-2 variants to cause illness in animal models, such as hamsters and mice.

There is a link between infection with the Delta and other variants and weight loss in hamsters and mice after 1 week, with some data suggesting a correlation between increased virus levels in the respiratory tract and weight loss.

However, various research groups have independently shown an absenceTrusted Source of such weight loss in hamsters and mice after an Omicron infection.

Moreover, these studies found that the hamsters with an Omicron infection showed higher or similar levels of virus, compared with the wild-type SARS-CoV-2 and the Delta variant in the upper respiratory tract. By contrast, the researchers observed lower levels of the virus in the lower respiratory tract after infection with the Omicron variant, compared with the Delta variant.

In sum, these studies show that Omicron may be less efficient at infecting the lungs. Significantly, these animal studies show that an Omicron infection results in lower levels of inflammation and injury to the lungs.

Consistent with this, there is growing evidence suggesting that people with an Omicron infection are less likely to be hospitalized or to require intensive care unit admission or mechanical ventilation than individuals with the Delta variant.

“We are seeing [that] the majority of patients infected with Omicron have mild disease that is more localized to the upper respiratory tract and that hospitalizations are not rising as fast as they have with prior variants,” Dr. Roberts added.

“However, hospitalizations and deaths lag behind overall case counts, and as our cases are continuing to rise and set daily records, we ultimately need to wait several more weeks to get a full picture of disease severity here, in the United States.”

Source: Medical News Today

Climate change: Substituting food items rather than whole diets can still make a big difference

 

• Humans’ food systems account for around a third of global greenhouse gas emissions.
• Consequently, if a person changes the foods they eat, they could reduce their carbon footprint.
• However, wholesale dietary changes may be one step too far for some people.
• In the present study, researchers found that substituting particular food items — rather than whole diets — can still significantly reduce an individual’s carbon footprint.

In a new study, researchers have found that a person can potentially reduce their carbon footprint significantly by substituting particular food items — in particular, beef.

The research, which appears in the American Journal of Clinical Nutrition, may motivate people to adapt their diet since it does not indicate a need to make wholesale changes to what they cook and eat.

Food and global heating

Researchers have found that human food systems cause around one-third of global greenhouse gas emissions. Greenhouse gases are a key driver of global heating, which threatens ecosystems and biodiversity, as well as human health.

Individuals can reduce their contributions to greenhouse gas emissions and global heating by changing the types of food they consume.

However, some people may find changing to an entirely new diet challenging, particularly if they have never prepared or eaten the foods the new diet requires.

The researchers behind the present study wanted to see if making a minor change — for example, substituting a single food item in a person’s diet — could also significantly reduce their carbon footprint. If so, this might be a more feasible approach than a person changing their diet completely.

Dr. Diego Rose spoke to Medical News Today. Dr. Rose is the study’s lead author and is Professor and Director of Nutrition at the School of Public Health & Tropical Medicine, Tulane University, New Orleans.

“Previously, we developed techniques to assess the carbon footprints of self-selected American diets for large samples of individuals. When we ranked these individuals’ 1-day diets by their carbon footprints, we found that the top 20% of individuals accounted for an outsized share (46%) of the total impact.”

“We wanted to know what was driving these higher impact diets, so we drilled down into the individual diets, looking at each item they ate on a given day. In many cases, we saw that just one item in the diet turned an otherwise average diet into a high-impact diet.”

Over 16,000 study participants

To do this, Dr. Rose and his colleagues drew on data from the National Health and Nutrition Examination Survey (NHANES)Trusted Source between 2005–2010. They included data from 16,800 18 years or older participants who had given information on a 24-hour dietary recall to interviewers.

The researchers then looked at the daily reported greenhouse gas emissions and water scarcity footprint.

With this information, the researchers could then identify food items that contributed the most to the adverse effects of a person’s diet and propose substitute items that might substantially reduce these adverse effects.

Beef — a key contributor

The researchers found that beef had the most significant adverse environmental effect. Approximately 20% of the participants ate beef at least once a day.

If the participants placed their beef consumption for another type of meat, such as turkey, they would reduce the greenhouse gas emissions associated with their diet by 48%. This change would also reduce the participants’ water scarcity footprint by 30%.

MNT spoke to Dr. Rosalind Fallaize, a lecturer in Nutrition and Dietetics at the University of Hertfordshire, Hatfield, United Kingdom. Dr. Faillaize said it was important to consider both climate change and health impacts, as the study does. However, she also highlighted that it is also important to consider the costs of switching food items.

“The analysis shows us that small dietary substitutions — [that is,] swapping beef [for] pork [or] poultry products — can reduce the environmental impact of our diets while maintaining overall diet quality. This study uses a large [United States] dataset and robust methods. It is great to see the combined consideration of the environmental impact and diet quality.”

“The paper considers a measure of diet quality — the Healthy Eating Index — to evaluate the dietary impact of the changes, ensuring that substitutions do not negatively impact this. [However,] it would be interesting to explore the impact of these changes at the micronutrient level, that is, vitamins and minerals — for example, beef contains more vitamins B12 and folate than poultry.”

‘Self-efficacy:’ Why smaller changes are easier

For Dr. Rose, a strength of the findings is that they increase a person’s chances of reducing their adverse climate effects. This is because substituting a single, high-impact food item is less of a change than switching an entire diet and so more likely to happen.

“It’s pretty clear from [the] research that people will not make changes if they don’t feel they are able to make changes. This ‘self-efficacy,’ or belief in one’s ability to succeed, is at the core of behavioral change theories.”

“A simple change, especially when you’re not giving up much, is obviously easier to remember and to enact [than] complex changes. Once made, the change reinforces one’s ability to succeed, and a positive feedback loop can be created for additional changes,” said Dr. Rose.

Dr. Fallaize agreed.

“The authors cite a very important aspect of changing behavior in their paper: self-efficacy, or the belief in our own ability to perform a behavior, for example, swapping beef for pork at dinner.”

“Small substitutions are often much easier to adopt than whole diet changes [or] overhauls — [for example,] swapping from a meat-based to a strict vegan diet — so we may feel more confident in our ability to do this.”

“Substitution of beef with poultry [or] pork is also more likely to draw on the same cooking skills, removing the frequently-faced barrier of not knowing how to prepare [or] cook or incorporate new or different foods in your diet. Once this small substitution has embedded into our diet [or] lifestyle, we can then try another.”

“Ultimately, small substitutions are more likely to become lasting changes, which is the goal when trying to adopt a more sustainable and or healthier diet,” said Dr. Fallaize.

Source: Medical News Today

Parkinson's disease: Move regularly with intensity to delay symptoms

 

• Regular moderate-to-vigorous physical activity improves the clinical progression of early-stage Parkinson’s disease.
• Different types of activities have different effects on the progression of the condition.
• Regular physical activity may improve the long-term clinical outcome of Parkinson’s disease.

Parkinson’s disease (PD) is one of the most common neurodegenerative diseases, second only to Alzheimer’s disease. The condition affects people of all races and cultures. Globally it affects around 10 million individuals who are generally over 60 years of age, but it can occur in younger people — 1 in 10 are under 50.

It is a progressive disease with symptoms that begin gradually.

Symptoms include:

• trembling of the face, legs, arms, or hands
• rigidity or stiffness in the limbs and trunk
• slow movement with balance and coordination issues
• cognitive decline in the later stages of the disease

The exact cause of the disease is unknown, but experts believe it develops due to genetic and environmental factors. Research has found that symptoms arise because of the death of dopamine-generating cells in the substantia nigra, the part of the brain responsible for movement, reward, and addiction.

Currently, levodopa, a drug that the brain converts into dopamine, helps manage PD symptoms. However, individuals can experience side effects, and the drug does not delay the progression of the disease.

However, new research from Kyoto University in Japan has shown that exercise twice a week can slow the progression of PD in people in the early stages of the condition.

Exercise as a treatment

Health experts have long suggested exercise as a way to alter the progression of PD. Studies have shown that high-intensity exercise can improve motor functionTrusted Source while dance training improves balanceTrusted Source and walking stability.

Now, a recent study in Neurology has shown that the effect of exercise extends beyond the duration of the physical activity itself. It also suggests regular exercise can change the progression of PD over the longer term.

The study involved 237 patients with early-stage PD and 158 healthy volunteers. Researchers gave them annual questionnaires to record exercise intensity, frequency, and duration. They also administered cognitive tests to assess their memory and verbal skills.

At the start of the study, the researchers found that the patients with PD had worse motor, cognitive and autonomic functions than the healthy group. However, there was no difference in regular physical activity and intensity levels between the groups.

PD clinical progression and exercise

The study led by Dr. Kazuto Tsukita found that overall regular physical activity had a significant effect on the balance and stability of the participants. Patients with early-stage PD who took 4 hours of moderate-to-vigorous exercise each week had a slower decline in balancing and walking compared to those who took less exercise.

Speaking to Medical News Today, Dr. Tsukita explained: “One very important message from our research is that the domains that are most improved by exercise are those that cannot be improved by drugs (i.e., postural and gait stability, processing speed, etc.).”

He went on to say, “I believe that exercise should be used in conjunction with, not in place of, drug therapy.”

Symptoms and activity

Dr. Gilbert went on to say that in her opinion, “one of the strengths of the study is that it investigated not just the effects of exercise, but of physical activity, defined as daily life activities performed in the course of work, leisure, or household related pursuits, that require exertion.”

Interestingly, the researchers found that different types of activity had different clinical effects.

“Increased physical activity was correlated with slower deterioration of a number of PD symptoms, implying that energy expenditure of all kinds, and not just formal exercise, is crucial in managing PD symptoms,” commented Dr. Gilbert.

Specifically, the study showed that moderate-to-vigorous exercise increased the balance and stability of individuals over time when compared to household, work, and overall leisure activities. In the same way, work-related activity levels showed a stronger reduction in the decline of processing speed.

The researchers gave participants 90 seconds to match numbers with figures to measure mental processing speed. With a maximum score of 110, those who did less exercise dropped from a score of 44 to 40 over 6 years. People who did more exercise dropped only one point from 44 to 43.

The study showed the progression of the disease was better altered in those who had maintained their physical activity over time, showing an association between maintaining a regular exercise regime and delaying the effects of the disease.

“This suggests that people with PD who may not have been particularly active at the beginning of their illness have much to gain in increasing their activity levels once the disease is underway,” said Dr. Gilbert.

Source: Medical News Today

Common chemical may disrupt pregnancy hormone

 

• Phthalates, which manufacturers commonly add to plastics, have been the subject of much research over the last 2 decades.
• Experts consider several phthalates to be endocrine disruptors and reproductive toxicants.
• According to a recent study, phthalates may negatively affect hormones that the placenta produces during pregnancy.

Phthalates are commonly used synthetic chemicals in plastics and personal care items.

A recent study, which appears in Environmental International, shows a possible link between exposure to phthalates and the disruption of an important hormone necessary to sustain a healthy pregnancy.

The Consumer Product Safety Improvement Act of 2008 limited the use of a handful of phthalates in many household products, especially those that children use. However, these chemicals and many others like them are still present in everyday goods.

Environmental exposureTrusted Source, which can occur by ingestion or inhalation or through the skin, means that most people have measurable levels of these ubiquitous chemicals in their body.

The placenta produces corticotropin-releasing hormone (CRH), the level of which increases throughout the course of pregnancy. The brain also produces CRH as part of the body’s stress response.

During pregnancy, the level of placental CRH is up to 10,000 times higherTrusted Source than it is in those who are not pregnant. The concentration of placental CRH tends to increase later during pregnancy, and researchTrusted Source has shown it to regulate labor-promoting contractions.

However, when CRH levels are excessively high or rise rapidly earlier in pregnancy, issues such as preterm birth, fetal growth problems, high blood pressure, gestational diabetes, or postpartum depression may result.

CRH and phthalates

The recent study was one of the first to examine the effect that phthalates have on placental CRH. Study co-author Emily Barrett, Ph.D., associate professor of biostatistics and epidemiology at the Rutgers School of Public Health in Piscataway, NJ, spoke with Medical News Today.

Barrett explained that scientists “have spent many years learning about how exposure to phthalates in humans impacts fetal development and, by extension, children’s health.”

“In fact,” she continued, “we’ve shown that prenatal phthalate exposure appears to increase the odds of preterm birth and, after birth, [phthalates] may alter growth, neurodevelopment, and more. These effects may be through changes in key hormones like testosterone, estrogens, and thyroid hormones.”

“What stimulated our interest in this topic was that we recognized a gap in the literature. No one had looked at whether phthalates interfere with corticotropin-releasing hormone.”

The Conditions Affecting Neurocognitive Development and Learning in Early Childhood study, or CANDLE, recruited 1,018 pregnant women receiving prenatal care at selected clinics in Shelby County, TN, from 2001 to 2011.

The researchers collected urine samples from each participant during two prenatal visits. One visit occurred at 16–29 weeks gestation and the other at 22–39 weeks. They measured urinary phthalate metabolites to assess phthalate exposure.

The team found that the presence of various phthalates was associated with higher placental CRH levels in mid-pregnancy and a drop in CRH levels later in the pregnancy.

The hormone levels were highest in the women who developed pregnancy complications, such as gestational diabetes and high blood pressure.

The authors list several strengths and limitations of the study. The most notable strength was the large number of participants, of whom more than half were Black women. People of Color are typicallyTrusted Source underrepresented in pregnancy studies, but they may experience higher phthalate exposures in lifestyle and consumer goods.

Limitations include the fact that the researchers only tested each woman twice during their pregnancy. Also, some phthalates are short-livedTrusted Source within the human body, so a single spot urine test only represents recent exposure and may over- or underestimate exposure levels throughout pregnancy.

Source: Medical News Today

What do studies say about the link between diabetes and vitamin D levels?

 Proposing that vitamin D is a panacea that could prevent, or even cure, a range of diseases is a sure way to start a fight in some circles. The role of vitamin D in diabetes has been investigated for years without yielding clear conclusions. So what do the studies actually say?

Diabetes, both types 1 and 2, are potentially life threatening and certainly life changing conditions that affect people worldwide. Case numbers increased nearly fourfold between 1980 and 2014 according to the World Health Organization (WHO)Trusted Source, with associated increases in mortality and disability caused by the disease.

The majority of those cases are type 2 diabetes, caused by excess visceral fat, though the interactionTrusted Source between genetic susceptibility, environment, obesity, and sedentary lifestyle is complex. It is not uncommonTrusted Source for people to have a moderate body mass index (BMI) and type 2 diabetes, though they still respond to weight loss.

Case numbers of type 1 diabetes are also growing. The reasons for this are not well understood, but some have compared the increase in type 1 diabetes cases to those of other autoimmune diseases such as multiple sclerosis. Both are more common in the northern hemisphere, as is vitamin D deficiency.

In fact, estimates suggest that as many as 40% of Europeans are vitamin D deficient, and 13% may be severely so — and the situation is worse still for individuals with dark skin. It is also difficult to ascertain how many people are deficient, as debate rages over the definition of deficiency.

Dr. Victoria Salem, a consultant endocrinologist and clinical scientist based at Imperial College London, told Medical News Today in an interview: “We know that type 1 diabetes is much more prevalent in the northern hemisphere and that’s usually put down to the fact that we get less sunlight and therefore have less vitamin D levels. That’s true also for multiple sclerosis. But it’s essential that that’s an association.”

While it is just an association, the links do not stop there. “[There is] quite good data showing that vitamin D deficiency, frank deficiencies — so children who’ve got rickets — are much more likely later in life to develop type 1 diabetes. But equally, people who are given a high dose of vitamin D […] are also less likely to get type 1 later on,” she explained.

Of course, suggesting vitamin D, or lack of it, is responsible for disease or susceptibility to it, is rife with controversy. Particularly with the heavily racialised discussion over the role of vitamin D deficiency in susceptibility to COVID-19.

The controversy over the role of vitamin D in diabetes is most likely due to poorly designed trials that have failed to adequately measure the impact of vitamin D supplementation on groups that can be generalized, a recent update in the European Journal of Clinical NutritionTrusted Source argued.

Vitamin D and the pancreas

Type 2 diabetes is typically diagnosed when high blood glucose levels are detected. This is ultimately caused by low insulin sensitivity in the tissues which makes it hard for the body to take glucose out of the blood.

To compensate for this lack of sensitivity, the body creates a larger amount of insulin until eventually the beta cells in the pancreas give up, and the affected individual cannot produce enough insulin to transport glucose into their cells, resulting in high blood sugar. It is often at this point that people receive the diagnosis of type 2 diabetes.

Dr. James Brown from Aston Research Centre for Healthy Ageing, Aston University in Birmingham, United Kingdom, studies type 2 diabetes and metabolism and explained the theory to MNT in an interview:

Early intervention could be the key

This theory has led to studies that hoped to determine if vitamin D could prevent or even treat type 2 diabetes. The largest of those studies in recent years was the D2D studyTrusted Source. This National Institutes of Health-funded study was the first large-scale randomized control trial of its kind and sought to determine if vitamin D supplementation would help reduce the risk of type 2 diabetes among people with prediabetes, a condition where blood glucose is already slightly elevated.

Researchers followed 2,423 participants for 2.5 years, with half assigned to take 4,000 IU — 100 micrograms (mcg) — of vitamin D supplementation a day, while half took no supplement.

At the end of the trial, results in the New England Journal of Medicine showed that those who had taken vitamin D supplementation had a higher level of vitamin D in their blood. Though they were 12% less likely to develop type 2 diabetes during the study, this was not found to be significantly different to the group who received no supplementation.

Source: Medical News Today

Brain damage markers greater in people with severe COVID-19 than those with Alzheimer's

 

• A study demonstrated that participants hospitalized with COVID-19 experiencing neurological complications had higher levels of blood proteins or biomarkers associated with neurological damage than people with Alzheimer’s.
• Increased biomarker levels correlated with COVID-19 severity, mortality risk, and the presence of neurological disorder.
• Long-term follow-up is necessary to determine if biomarker elevation is associated with an increased risk of developing subsequent neurodegenerative disorders.

COVID-19Trusted Source, the disease that a SARS-CoV-2 infection causes, often brings on mild upper respiratory symptoms. However, some individuals may experience severe illness requiring hospitalization. This can occur due to pneumonia and lung damage causing respiratory failure.

In addition, neurological manifestations commonly occur in people hospitalized with COVID-19. Neurological disorders may include encephalopathy, seizures, stroke, encephalitis, Guillain-Barré syndromeTrusted Source, and acute demyelinating encephalomyelitisTrusted Source.

Researchers at NYU Grossman School of Medicine conducted a study that investigated whether people with COVID-19 experiencing new-onset neurological complications during hospitalization had elevated blood markers indicating neurological damage.

The investigators published study results in the journal Alzheimer’s and DementiaTrusted Source.

Dr. Thomas Wisniewski, M.D., a co-author of the study, professor of neurology, pathology, and psychiatry, and director of both the NYU Alzheimer’s Disease Research Center and the Center for Cognitive Neurology, spoke about the study in an MNT interview.

He explained: “It’s clear that the [SARS-CoV-2] virus has a propensity for inducing vascular damage, targeting in the endothelial cells, and causing disruption of the blood-brain barrier, as well as inducing generalized neuroinflammation. Cytokines like interleukin 6 and interleukin 1 are much elevated in [individuals with COVID-19], and these are cytokines that drive neurodegeneration and Alzheimer’s disease.”

Cytokines are proteins that help the body’s cells to communicate.

Dr. Wisniewski added, “In our study, we became interested in looking at these types of biomarkers, [since these biomarkers] are what we follow in our Alzheimer’s disease research center for looking at the progression of Alzheimer’s-related pathology and other neurodegenerative disorders.”

Neurodegenerative biomarkers

In an interview with MNT, Jennifer Bramen, Ph.D., a senior research scientist at the Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, CA, who was not involved in the study, described the seven biomarkers the study measured:

• Total tau and pTau181 are indicators of neuron damage. Their levels increase as AD progresses. In AD, abnormal proteins form tangles, blocking the communication between brain cells, she explained.
• Ubiquitin C-terminal hydrolase L1 (UCHL1) is an enzyme that breaks down unnecessary proteins in brain cells. Brain injury or neurodegenerative diseases such as AD cause levels of UCHL1 to increase.
• Increased glial fibrillary acidic protein (GFAP)Trusted Source levels indicate damage to the glial cells. Glial cells help maintain the health of brain cells and the blood-brain barrier, which filters toxic substances.
• Neurofilament light chain (NfL)Trusted Source measures damage to axons of myelinated neurons. The axon is the part of the neuron that conducts electricity, and myelin is the insulation surrounding the neuron.
• Amyloid-β (Aβ) 40 and 42Trusted Source are proteins that build up and cause the formation of amyloid plaques in AD, which disrupt brain cell function and communication.
• Lastly, a person’s pTau181 to Aβ42 ratio may identify early stages of AD.

Investigators also attempted to determine the association of increased biomarkers with rates of discharge to home and in-hospital death rates.

To assess the level of injury, the researchers compared serum biomarker levels of a control group of participants who had “normal” cognition, mild cognitive impairment (MCI)Trusted Source, and ADTrusted Source with the biomarkers of people during hospitalization with COVID-19 and new neurological findings.

Researchers conducted a retrospective analysis of participants enrolled in the Study of Neurologic and Psychiatric Events in Acute COVID-19 (SNaP Acute COVID study), which examined serum samples people gave during their hospitalization for COVID-19.

Dr. Wisniewski explained, “We specifically excluded patients who have a preexisting cognitive disorder, any sort of dementia, or mild cognitive impairment, [to prevent clouding of the results].”

The SNaP Acute COVID study was a prospective study of 4,491 participants conducted in four New York hospitals between March 10 and May 20 of 2020, which evaluated the development of new neurological events during acute COVID-19 hospitalization.

The non-COVID control group comprised blood samples from the NYU Alzheimer’s Disease Research Center clinical core cohort banked before January 1, 2020. This was the date of the first reported COVID-19 cases in New York City. The researchers used validated testing tools — version three of the Uniform Data Set and the Clinical Dementia RatingTrusted Source — to stratify the control participants into three subgroups: normal cognitive functioning, MCI, and AD.

The study measured blood markers using an ultrasensitive testing methodology called single-molecule array technology.

The COVID-19 group consisted of 251 participants with a median age of 71. This group was 63% male. There were 161 participants in the control group with a median age of 71. Participants in the control group were 35% male.

Source: Medical News Today