New patches made with human cells help boost recovery from heart attack

Agencies
January 13, 2018

Washington, Jan 13: A research has been conducted to enhance recovery from heart attack.For the first time, large human cardiac-muscle patches have been tested in the lab on large animals in a heart attack model. It showed that it resulted in improved recovery from heart attack injury.

This is the first large-animal study of muscle patches carried with a goal of treating human heart attacks by suturing cardiac-muscle patches over a specific area of dead heart muscles. It was carried out in order to reduce the pathology that often leads to heart failure.

The research was conducted by Jianyi `Jay` Zhang, from University of Alabama at Birmingham Biomedical Engineering, a joint department of the UAB School of Medicine and the UAB School of Engineering.Each patch is 1.57 by 0.79 inches in size and nearly as thick as a dime.

Zhang and colleagues found that transplanting two of these patches onto the infarct area of a pig heart significantly improved the function of the heart`s left ventricle, the major pumping chamber.

The patches also significantly reduced infarct size, which is the area of dead muscle; heart-muscle wall stress and heart-muscle enlargement; as well as significantly reducing apoptosis, or programmed cell death, in the scar border area around the dead heart muscle.Furthermore, the patches did not induce arrhythmia in the hearts, a serious complication observed in some past biomedical engineering approaches to treat heart attacks.

A mixture of three cells - two million endothelial cells - known to help cardiomyocytes function and survive in a micro-environment, 2 million smooth muscle cells - known to line blood vessels, and 4 million cardiomyocytes - known as heart-muscle cells, each patch is grown in a 3-D fibrin matrix.

Subsequently, it is rocked back and forth for a week and all cells start to beat synchronously after day one.The three cell types are differentiated in the making from cardiac-lineage human-induced stem cells, also known as hiPSCs.

Dynamic rocking and the apt mixture produce more quantity of mature heart-muscles cells, with more contractive force and superior physiological function, as compared to patches made with mono-layered cells which are not dynamically rocked.

In the past, attempts to use hiPSCs to treat large animal models of heart attacks have shown very low rates of engraftment or survival. The current research shows a relatively higher rate of engraftment - 10.9 percent - after four weeks of transplant which resulted in improved heart recovery.

These patches also release tiny blebs called exosomes which carry RNA and proteins from one cell to other. In tissue culture experiments, it is found that such exosomes which are released from large heart-muscle patches help in the survival of heart-muscle cells.

Additionally, these patches are found to reverse or prevent detrimental changes in protein phosphorylation in the sarcomeres of heart-muscle tissues bordering the infarct of the heart. This result suggested that hiPSC-derived heart cells may improve contractile function after heart attacks.

The research was conducted by the University of Alabama at Birmingham.

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Agencies
June 30,2020

Between 30-40 per cent of deaths from studies in intensive care units from different countries are people with diabetes, said Paul Zimmet, Professor of Diabetes, Monash University, Australia.

Zimmet, who is President International Diabetes Federation, added that the actual mechanism as to why COVID-19 may cause diabetes is as yet unknown, however, several possibilities exist. "COVID-19 is a very destructive and cunning virus and causes terrible damage to tissues including the lungs and pancreas," said Zimmet. Below are excerpts from an exclusive chat with IANS.

Why do you say Diabetes is dynamite if a person has been infected with COVID-19?

There have been many deaths in many countries, e.g. Italy, China, the UK and US among people with diabetes after infection with COVID-19 (SARS-Cov-2).

The mortality tends to be mainly in older Type 2 diabetics. Between 30-40 per cent of deaths from studies in intensive care units from different countries are people with diabetes. This outcome and other complications from the virus, particularly pneumonia, are more likely in people with diabetes which is poorly controlled with high blood sugars (poor metabolic control).

Diabetes is often associated with other chronic conditions, including obesity, hypertension and heart disease compounding the risk. These latter conditions all convey higher risk to COVID-19 infections.

ACE-2, which binds to SARS-Cov-2 and allows the virus to enter human cells is also located in organs and tissues involved in glucose metabolism. Is there solid evidence that virus after entering tissues may cause multiple and complex impairment of glucose metabolism?

The actual mechanism as to why COVID-19 may cause diabetes is as yet unknown.

However, several possibilities exist. Firstly, COVID-19 is a very destructive and cunning virus and causes terrible damage to tissues, including the lungs and pancreas.

A new study just published showed that in miniature lab-grown pancreas, and other cells such as liver, made using human stem cells, COVID-19 caused destruction of the pancreas beta cells that produce insulin.

It is possible that the virus causes disruption of the cells by disrupting cellular metabolism. This is possibly the way it brings about new-onset diabetes. ACE-2 exists in high concentration in the lung as this also explains the terrible lung side effects of COVID-19 infections.

Can COVID-19 lead to a new mechanism of diabetes? Probably a new form of diabetes or a new form of disease?

The COVID-19 virus has only been with us for about 5 months and there is a huge amount that we still must learn about its cunning and devastating ways. The purpose of the Global COVIDIAB Diabetes Registry, a joint initiative of Monash University in Australia, and King’s College London is to gain a much better understanding of how common is the appearance of COVID-19 related diabetes, what form does it take be it type 1 or type 2 or a new form, and how common are the complications that we already know e.g. diabetic keto-acidosis, hyperosmolar coma and high insulin requirements are causing high rates of ill health and mortality worldwide. The knowledge gained will aid our understanding for developing strategies to prevent and treat this terrible virus that has caused destruction globally.

Diabetes is one of the most prevalent chronic diseases in India. According to a recent study, sugar levels of diabetic persons increased by 20 per cent during nationwide lockdown in India to contain COVID-19 outbreak. Even after lockdown was lifted, many people are confined within their home. Do you think lack of physical activity will create more problems for diabetics?

My own major research has been on studying populations with high rates of diabetes, including ethnic Indian communities including India, Mauritius, and Fiji so I am very well aware of this. It is now well established that along with diabetes, that associated poor metabolic control of their diabetes places these people at the highest risk for COVID infection and its devastating complications and the associated morbidity and mortality. And these communities have high prevalence of heart disease as well.

Lockdown not only has deleterious effects on metabolic control of the diabetes through reduced opportunities for exercise to be protective serious consequences of SARS-CoV-2 infection, lockdown usually results in disruption of the regular medical care and the regular monitoring of metabolic control. This may also be partly due to the stress and poor compliance, or inability to afford their medications such as insulin. It may also be compounded by inability to access the care during the pandemic. Nevertheless, we now know that poor metabolic control heightens their risk as described above.

You have said diabetes is itself a pandemic just like Covid-19, and the two pandemics could be clashing. How could governments address this problem?

These are “The Times of COVID-19”. Most nations of the world were totally unprepared for a pandemic of this magnitude. They underestimated its potential impact and the destructive nature of the viral infection. This should prompt all countries to upgrade their guidelines to take into account the lessons learnt on infection control including training of staff specialising in infectious diseases and improved public education and taking their communities into their confidence about the terrible nature of COVID-19. The risks of COVID-19 infection need a much higher priority in the general community, particularly for people with chronic conditions such as diabetes, obesity, and cardiac conditions.

Governments are faced with chronic diseases (NCDs) like diabetes and communicable diseases (CDs) like viral and enteric diseases and TB. In general WHO gives the highest priority to communicable diseases and much less attention and funding to chronic diseases like diabetes (I was an adviser to WHO for many years (about 30) on diabetes and obesity and it was very frustrating to deal with this situation).

This attitude to diabetes, for example, has a flow down effect so that diabetes funding in countries by governments, rich and poor, suffered and was insufficient.

So now we have a COVID-19 pandemic and who are those at highest risk, yes people with diabetes and other NCDs, it is very important that now the two, Diabetes and COVID-19 are clashing face-to-face. This is a major issue that WHO and national governments have to face with equal priority’

Stressed people suffering from diabetes run a greater risk of poor blood glucose levels, what do you suggest to these people?

As mentioned in the answer above, stress is an important factor in upsetting the blood sugar (metabolic) control of diabetes. Additive to this is poor compliance with medications and diet. These and potential associated comorbidities due to other chronic conditions are part of the dynamic dynamite mixture.

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Agencies
May 9,2020

17-year-old Pratyusha Jha, wakes up scrambling for newspapers these days to look for any news about her pending board exams and is anxious about what the future has in store for her.

Similar concerns are shared by Bipin Kumar, a class 12 student, who says the announcement of board exams from July 1 to 15 brought limited clarity as the larger questions remain unanswered.

The COVID-19 lockdown, came with a different set of concerns for class 12 students, whose board exams were postponed midway following the outbreak of coronavirus, putting on hold their future plans as well.

"Everyday I have been looking for news about the exams and about entrance exam dates. I feel unfortunate that this happened during the year I was supposed to take the big college leap. I don't want my future decisions to be shaped by this very year as what I opt to study now will remain with me lifelong," Pratyusha told PTI.

Ending some uncertainty for students, HRD Minister Ramesh Pokhriyal 'Nishank' on Friday announced that the pending class 10 and 12 board exams will be held from July 1 to 15. While class 12 exams will be conducted across the country, the class 10 exams are only pending in North East Delhi where they were affected due to the law and order situation.

"The anxiety doesn't end here, there is no date sheet yet. What will be the modalities of exams, how will we reach centres, what protocols have to be followed, there is no clarity on that. My friends and I keep calling our school teachers and also the CBSE helpline to seek some clarity," Bipin Kumar said.

Vaibhav Sharma, a class 12 student in Gurgaon said, "There is no clarity yet. I wanted to apply for DU, but now that the exams are taking place in July when will the results be declared, when will cut offs be announced. If I don't get a good college here, will I be able to travel to different cities for admission, nothing is known yet."

Similarly, for the students in northeast Delhi, the wait for the exams has become a "test of patience" as they were postponed first in the area due to law and order situation, and later due to the coronavirus outbreak, resulting in a four-month-long wait for the exams.

"It has become an endless wait and now I don't feel like studying too. Right from childhood, we are taught that board exams are too crucial and have to be focussed at least two years in advance. But now, it is a different picture altogether," Rani Kumari, a resident of Chandbagh said.

Universities and schools across the country have been closed and exams postponed since March 16 when the Centre announced a countrywide classroom shutdown as one of the measures to contain the COVID-19 outbreak.

Later, a nationwide lockdown was announced on March 24, which has now been extended till May 17.

The board was not able to conduct class 10 and 12 exams on eight examination days due to the coronavirus outbreak. Further, due to the law and order situation in North East Delhi, the board was not able to conduct exams on four examination days, while a very small number of students from and around this district were not able to appear in exams on six days.

The board had last month announced that it will only conduct pending exams in 29 subjects which are crucial for promotion and admission to higher educational institutions. The modalities of assessment for the subjects for which exams are not being conducted will be announced soon by the board.

The schedule has been decided in order to ensure that the board exams are completed before competitive examinations such as engineering entrance JEE-Mains, which is scheduled from July 18-23, and medical entrance exam NEET, which is scheduled on July 26.

The University Grants Commission (UGC) has issued guidelines to universities that new academic session for freshers will begin from September while for the existing students from August.

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News Network
February 4,2020

Boston, Feb 4: Practising yoga may increase levels of a messenger molecule involved in regulating brain activity, and completing one yoga class per week may maintain elevated levels of this chemical, according to a study which may lead to better ways of mitigating depressive symptoms.

The study, published in the Journal of Alternative and Complementary Medicine, assessed a group of 30 clinically depressed patients who were randomly divided into two groups.

According to the researchers, including those from Boston University in the US, both groups engaged in coherent breathing, and Iyengar yoga -- a form of hatha yoga, developed by B. K. S. Iyengar, emphasising on detail, precision, and alignment in the performance of yoga postures.

The only difference between the groups, the scientists said, was the number of 90 minute yoga sessions, and home sessions in which each group participated.

Over three months, they said, the high-dose group (HDG) was assigned three sessions per week, while the low-intensity group (LIG) engaged in two sessions per week.

The participants underwent magnetic resonance imaging (MRI) scans of their brain before the first and after the last yoga session, and also completed a clinical depression scale to monitor their symptoms, the study noted.

Results of the study revealed that both groups had improvement in depressive symptoms after three months.

Their MRI analysis showed that levels of the brain messenger molecule GABA were elevated after three months of yoga, as compared to the levels before starting yoga.

According to the study, this increase was found for approximately four days after the last yoga session, but the rise was no longer observed after about eight days.

"The study suggests that the associated increase in GABA levels after a yoga session are 'time-limited' similar to that of pharmacologic treatments such that completing one session of yoga per week may maintain elevated levels of GABA," explained study co-author Chris Streeter from Boston University.

Providing evidence-based data may help in getting more individuals to try yoga as a strategy for improving their health and well-being, the scientists said.

"A unique strength of this study is that pairing the yoga intervention with brain imaging provides important neurobiological insight as to the 'how' yoga may help to alleviate depression and anxiety," said study co-author Marisa Silveri from Harvard University.

In this study, we found that an important neurochemical, GABA, which is related to mood, anxiety, and sleep, is significantly increased in association with a yoga intervention," Silveri said.

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