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Comment by Dr. Krishna Kumari Challa on June 30, 2021 at 3:50pm

COVID-19 Makes Lasting Changes to Blood Cells
Why does long COVID last for so long, leaving long-haulers with symptoms that persist for months after initial infection?

New evidence suggests the enduring imprint of COVID-19 could be due to the virus making significant alterations to people's blood – yielding lasting changes to blood cells that are still evident several months after infection is diagnosed.

While the pathology is not yet fully understood, hyper-inflammatory response and coagulation disorders leading to congestions of microvessels are considered to be key drivers of the still increasing death toll.

The results showed that red blood cells (erythrocytes) in COVID-19 patients varied more in size than those from healthy people, and showed signs of stiffness in their physical structure, exhibiting less deformability, which could affect their ability to deliver oxygen through the body.

"The physical properties of erythrocytes are crucial for microcirculatory flow and as such, these changes could impair circulation and promote hypoxemia.

The effect could persist in COVID-19 patients long after the infection is not active anymore; we found that in recovered patients phenotype alterations were not as prominent, but still present. In contrast, the researchers discovered that a form of white blood cells (leukocytes) called lymphocytes showed decreased stiffness in COVID-19 patients, while other white blood cells, known as monocytes, were significantly larger than in cells from the control group.

Meanwhile, neutrophils – another type of white blood cell – showed numerous changes in COVID-19 patients, seen in higher volume, with greater deformation.

the observed changes could arise due to cytoskeletal alterations of immune cells. Mechanical properties of cells can be directly related to the cytoskeleton, an important supportive structure which also determines cellular function."

https://www.cell.com/biophysj/pdf/S0006-3495(21)00454-9.pdf

https://www.sciencealert.com/covid-19-is-making-lingering-changes-t...

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Comment by Dr. Krishna Kumari Challa on June 30, 2021 at 11:24am

Delhi: New virus, Cytomegalovirus, found in Covid patients

As the world prepares itself against the new and emerging Delta Plus strain of the coronavirus, India has reported a new type of virus in people who have already suffered COVID-19.

Delhi’s Ganga Ram Hospital has reported five cases of Cytomegalovirus (CMV) in Covid patients, the hospital reported in a written statement

Comment by Dr. Krishna Kumari Challa on June 30, 2021 at 11:18am

Scientists discover new type of quasiparticle

Russian scientists have experimentally proved the existence of a new type of quasiparticle - previously unknown excitations of coupled pairs of photons in qubit chains. This discovery could be a step towards disorder-robust quantum metamaterials. The study was published in Physical Review B.

Superconducting qubits are a leading qubit modality today that is currently being pursued by industry and academia for quantum computing applications. However, the performance of quantum computers is largely affected by decoherence that contributes to a qubits extremely short lifespan and causes computational errors. Another major challenge is low controllability of large qubit arrays.

Metamaterial quantum simulators provide an alternative approach to quantum computing, as they do not require a large amount of control electronics. The idea behind this approach is to create artificial matter out of qubits, the physics of which will obey the same equations as for some real matter. Conversely, you can program the simulator in such a way as to embody matter with properties that have not yet been discovered in nature.

Arrays of superconducting qubits are generally described by the Bose-Hubbard model. An interesting feature of the Bose-Hubbard model is the emergence of bound boson pairs (doublons) caused by the strong quantum nonlinearity. The topological physics of doublons has been extensively explored in a series of recent theoretical works. However, the experimental investigation of topological properties of bound photon pairs is still lacking.

the scientists were able to demonstrate for the first time that a new type of quasiparticles - doublon topological excitations - can arise in qubit chains.

https://www.eurekalert.org/pub_releases/2021-06/nuos-sdn062921.php

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Comment by Dr. Krishna Kumari Challa on June 30, 2021 at 9:46am

Researchers discover unique 'spider web' mechanism that traps, kills viruses

Immunologists  have discovered a previously unknown mechanism which acts like a spider web, trapping and killing pathogens such as influenza or SARS-CoV-2, the virus responsible for COVID-19.

The researchers have found that neutrophils, the most abundant white blood cells in the human body, explode when they bind to such pathogens coated in antibodies and release DNA outside of the cell, creating a sticky tangle which acts as a trap.

The findings, published online in the Proceedings of the National Academy of Science, are significant because little is understood about how antibodies neutralize viruses in the respiratory tract.

The discovery has implications for vaccine design and delivery, including aerosol and nasal spray technologies that could help the body head off infections before they have a chance to take hold.

Researchers caution that while the body's spider-web mechanism has the potential to be hugely beneficial, it can cause harm too, including inflammation and further illness when the web formation is uncontrollable.

Hannah D. Stacey et al, IgA potentiates NETosis in response to viral infection, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2101497118

https://medicalxpress.com/news/2021-06-unique-spider-web-mechanism-...

Comment by Dr. Krishna Kumari Challa on June 29, 2021 at 1:54pm

Broken Heart Syndrome Linked to the Brain

A chronically stressed amygdala can prime the heart to overreact to acute stress events, a new study shows.

Takotsubo syndrome, also known as broken heart syndrome, is a rare, reversible condition with symptoms mimicking a mild heart attack. A disease that disproportionately affects women, TTS is triggered by stressful events such as bankruptcy, the death of a loved one, or divorce, and results in a weakening of the heart’s left ventricle such that it becomes temporarily misshapen.

Previous work has shown that TTS patients have elevated activity in their amygdala, a brain region involved in stress response. What has never been clear, however, is whether this activity in the brain happens as a result of the syndrome or whether it began many years before.

Higher amygdala activity was associated with an increased risk for TTS, and among those with the condition, patients with higher ratios had developed TTS roughly two years earlier following the imaging than those with lower ratios. “We can now show that this syndrome happens as a result of chronic stress over years that makes you vulnerable to developing the syndrome more easily and sooner than [less stressed] people.

This study confirms our suspicion that there’s a relationship between amygdala activity and future risk of Takotsubo.

A. Radfar et al., “Stress-associated neurobiological activity associates with the risk for and timing of subsequent Takotsubo syndrome,” Eur Heart J, ehab029, 2021

https://www.the-scientist.com/the-literature/broken-heart-syndrome-...

Comment by Dr. Krishna Kumari Challa on June 29, 2021 at 12:22pm

Study explores how the perception of internal bodily signals influences the concept of self

In contrast with other animal species on Earth, over the course of their life, humans can develop a fairly clear idea of who they are as individuals and what sets them apart from others. This abstract concept of self is known to be fragmented and fuzzy in individuals with certain psychiatric disorders, including schizophrenia, borderline personality disorder and dissociative identity disorder.

Researchers recently authored a review paper examining experimental evidence suggesting that the birth, maintenance and loss of this abstract concept of self is deeply tied to what is known as interoception. This refers to an individual's sense of his/her internal physiological signals.

A couple of years ago, researchers discovered a new bodily illusion. This 'embreathment' illusion, as they called it, suggests that your concept of yourself (i.e., who you think you are) is partly shaped by feelings that come from your viscera, particularly from the heart and the lungs.

They realized that the concept of self has several dimensions, ranging from mundane and material to social and spiritual. They thus decided to investigate the illusion more in depth and try to better understand what it suggested about people's concept of self.

The inside of me: interoceptive constraints on the concept of self in neuroscience and clinical psychology. Psychological Research(2021). DOI: 10.1007/s00426-021-01477-7.

The "embreathment" illusion highlights the role of breathing in corporeal awareness. Journal of Neurophysiology(2020). DOI: 10.1152/jn.00617.2019.

Gut markers of bodily self-consciousness. bioRxiv. DOI: 10.1101/2021.03.05.434072.

https://medicalxpress.com/news/2021-06-explores-perception-internal...

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Comment by Dr. Krishna Kumari Challa on June 29, 2021 at 6:30am

Comment by Dr. Krishna Kumari Challa on June 29, 2021 at 6:24am

Sneeze Cam Reveals Best Types of Masks

Comment by Dr. Krishna Kumari Challa on June 29, 2021 at 6:14am

Study identifies heart block cause in athletes
An international team of scientists has identified why some endurance athletes experience a heart rhythm disturbance called ‘heart block’.

The study found that long-term exercise in retired racehorses – the best available model of the athlete’s heart - and in mice, triggered molecular changes in a part of the heart known as the atrioventricular (or AV) node.

The work is the latest in a series of studies conducted by the team, showing that endurance exercise directly impacts the electrical wiring system of the heart.

Despite well-recognised cardiovascular benefits, sustained endurance exercise in athletes, footballers and other sportspeople can lead to the development of abnormal heart rhythms - known as cardiac arrhythmias, including heart block.

While benign for many people, heart block - also known as AV block - can be a precursor to more serious heart problems.
The heart’s AV node is part of its electrical conduction system controlled by the autonomic nervous system and electrically connects the atria and ventricles.

It’s well known that athletes are predisposed to heart block which in itself is often benign. But clinical research suggests that this may be ‘a canary in a coalmine’: it can flag up the risk of abnormal heart rhythms which may for example necessitate the implantation of a pacemaker in some individuals.For the first time this research highlights the fundamental adaptations taking place.

The study, published in the leading journal Circulation Research, found that long-term training in both horses and mice caused a reduction in key proteins, known as ion channels, that control AV node conduction.
Training-induced heart block and underlying ion channel changes were reversible when the exercise was stopped or when mice were given a compound known as an anti-microRNA.
It must be stressed that exercise is good for you – and its benefits far outweigh the risks.
Understanding the physiology of the athlete’s heart is incredibly helpful: it could help us develop new interventions for heart block as well as help doctors more effectively monitor heart rhythm disturbances in top-flight professional athletes
https://www.ahajournals.org/doi/10.1161/CIRCRESAHA.119.316386
https://researchnews.cc/news/7491/Study-identifies-heart-block-caus...

Comment by Dr. Krishna Kumari Challa on June 28, 2021 at 11:02am

Muscle's smallest building blocks disappear after stroke

After suffering a stroke, patients often are unable to use the arm on their affected side. Sometimes, they end up holding it close to their body, with the elbow flexed.

In a new study, Northwestern University and Shirley Ryan AbilityLab researchers have discovered that, in an attempt to adapt to this impairment, muscles actually lose sarcomeres—their smallest, most basic building blocks.

Stacked end to end (in series) and side to side (in parallel), sarcomeres make up the length and width of muscle fibers. By imaging biceps muscles with three noninvasive methods, the researchers found that stroke patients had fewer sarcomeres along the length of the muscle fiber, resulting in a shorter overall muscle structure.

The research was published today (June 25) in the Proceedings of the National Academy of Arts and Sciences.

This finding is consistent with the common patient experience of abnormally tight, stiff muscles that resist stretching, and it suggests that changes in the muscle potentially amplify existing issues caused by stroke, which is a brain injury. The team hopes this discovery can help improve rehabilitation techniques to rebuild sarcomeres, ultimately helping to ease muscle tightening and shortening.

Amy N. Adkins et al, Serial sarcomere number is substantially decreased within the paretic biceps brachii in individuals with chronic hemiparetic stroke, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2008597118

https://medicalxpress.com/news/2021-06-muscle-smallest-blocks.html?...

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