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Archive for the ‘COVID-19’ Category


Early Details of Brain Damage in COVID-19 Patients

Reporter: Irina Robu, PhD

 

COVID-19 has currently claimed more American lives than World War I, Vietnam War and the Korean war combined. And while it is mainly a respiratory disease, COVID-19 infection affects other organs, including the brain. Researchers at Harvard-affiliated Massachusetts General Hospital found that COVID patients with neurological symptoms show more than some metabolic disturbances in the brain as patients who have suffered oxygen deprivation.

During the course of the pandemic, thousand patients with COVID-19 have been seen at MGH and the severity of the neurological symptoms varies from temporary loss of smell to more severe symptoms such as dizziness, confusion, seizures, and stroke. According to the principal investigator of the study, Eva Maria Ratai, Department of Radiology used 3 Tesla Magnetic Resonance Spectroscopy (MRS) to identify neurochemical abnormalities even the structural imagining findings are normal. COVID-19 patients’ brains showed N-acetyl-aspartate (NAA) reduction, choline elevation, and myo-inositol elevation, comparable to what is seen with these metabolites in other patients with leukoencephalopathy after hypoxia without COVID.

Their research indicated that one of patients with COVID-19 indicate the most severe white matter damage, whereas another had COVID-19 associated necrotizing leukoencephalopathy at the time of imaging. And the patient that experience cardiac arrest showed subtle white matter changes on structural MR. The control cases included one patient with damage due to hypoxia from other causes: one with sepsis-related white matter damage, and a normal, age-matched, healthy volunteer.

The main question still remains whether the decrease in the oxygen of the brain is causing the white matter to change or whether the virus itself is attacking white matter. The conclusion is that MRS can be used as a disease and therapy monitoring tool.

SOURCE

Small study reveals details of brain damage in COVID-19 patients

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Mechanistic link between SARS-CoV-2 infection and increased risk of stroke using 3D printed models and human endothelial cells

Reporter: Adina Hazan, PhD

 

Kaneko, et al.  from UCLA aimed to explore why SARS-CoV-2 infection is associated with an increased rate of cerebrovascular events, including

  • ischemic stroke and
  • intracerebral hemorrhage

While some suggested mechanisms include an overall systemic inflammatory response including increasing circulating cytokines and leading to a prothrombotic state, this may be only a partial answer. A SARS-CoV-2 specific mechanism could be likely, considering that both angiotensin-converting enzyme-2 (ACE2), the receptor necessary for SARS-CoV-2 to gain entry into the cell, and SARS-CoV-2 RNA have been reportedly detected in the human brain postmortem.

One of the difficulties in studying vasculature mechanisms is that the inherent 3D shape and blood flow subject this tissue to different stressors, such as flow, that could be critically relevant during inflammation. To accurately study the effect of SARS-CoV-2 on the vasculature of the brain, the team generated 3D models of the human middle cerebral artery during intracranial artery stenosis using data from CT (computed tomography) angiography. This data was then exported with important factors included such as

  • shear stress during perfusion,
  • streamlines, and
  • flow velocity to be used to fabricate 3D models.

These tubes were then coated with endothelial cells isolated and sorted from normal human brain tissue resected during surgery. In doing so, this model could closely mimic the cellular response of the vasculature of the human brain.

Surprisingly, without this 3D tube, human derived brain endothelial cells displayed very little expression of ACE2 or, TMPRSS2 (transmembrane protease 2), a necessary cofactor for SARS-COV-2 viral entry.

Interestingly,

  • horizontal shear stress increased the expression of ACE2 and
  • increased the binding of spike protein to ACE2, especially within the stenotic portion of the 3D model.

By exposing the endothelial cells to liposomes expressing the SARS-CoV-2 spike protein, they also were able to explore key upregulated genes in the exposed cells, in which they found that

  • “binding of SARS-CoV-2 S protein triggered 83 unique genes in human brain endothelial cells”.

This included many inflammatory signals, some of which have been previously described as associated with SARS-COV-2, and others whose effects are unknown. This may provide an important foundation for exploring potential therapeutic targets in patients susceptible to cerebrovascular events.

Overall, this study shows important links between the

  • mechanisms of SARS-CoV-2 and the
  • increase in ischemic events in these patients. It also has important implications for
  • treatment for SARS-CoV-2, as high blood pressure and atherosclerosis may be increasing ACE2 expression in patients, providing the entry port for viral particles into brain endothelia.

SOURCE:

https://www.ahajournals.org/doi/10.1161/STROKEAHA.120.032764

Other related articles published in this Open Access Online Scientific Journal include the following:

The Impact of COVID-19 on the Human Heart

Reporters: Justin D. Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2020/09/29/the-impact-of-covid-19-on-the-human-heart/

 

SAR-Cov-2 is probably a vasculotropic RNA virus affecting the blood vessels: Endothelial cell infection and endotheliitis in COVID-19

Reporter: Aviva Lev-Ari, PhD, RN – Bold face and colors are my addition

https://pharmaceuticalintelligence.com/2020/06/01/sar-cov-2-is-probably-a-vasculotropic-rna-virus-affecting-the-blood-vessels-endothelial-cell-infection-and-endotheliitis-in-covid-19/

 

Diagnosis of Coronavirus Infection by Medical Imaging and Cardiovascular Impacts of Viral Infection, Aviva Lev-Ari, PhD, RN  Lead Curator – e–mail: avivalev-ari@alum.berkeley.edu

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Mysteries of COVID Smell Loss

Reported : Irina  Robu, PhD

When Covid-19 patients have smell loss it tends to be sudden and severe. They are usually don’t have a blocked, stuffy or runny nose – most people with coronavirus can still breathe freely.  Since the epidemy started in march, an estimated of 80 percent of people with COVID-19 have experience smell disturbances in addition to loss of taste and the ability to smell chemical irritants. Research has shown that smell loss is common in people with COVID-19 disease, the reason why researchers and doctors have recommended to use a diagnostic test to determine if a patient has COVID-19.

Yet, the mystery is how the new coronavirus robs patients of their senses. During the early days of the epidemic, physicians and researchers thought that COVID related loss of smell might signal that the virus makes its way into the brain through the nose, where it can do the most severe damage. According to Sandeep Robert Data, a neuroscientist at Harvard Medical School, the research data showed that the primary source is the in the nose, but more specifically in the nasal epithelium. It looks like the virus attacks the cells responsible for registering odors rather than attacking neurons directly.  

It is well known that  olfactory neurons do not have angiotensin-converting enzyme 2 (ACE2) receptors, which permit the virus entry to cells, on their surface. But sustentacular cells, which provide support for  olfactory neurons are scattered with the receptors. These cells preserve the important  balance of salt ions in the mucus that neurons rest on on to send signals to the brain. If that balance is disturbed, it could lead to a closure of neuronal signaling and loss of smell.

The sustentacular cells correspondingly deliver the metabolic and physical support necessary to keep the fingerlike cilia on the olfactory neurons wherever receptors that detect odors are disturbed. Nicolas Meunier, a neuroscientist at the Paris-Saclay University in France determined that disruption of the olfactory epithelium might explain the loss of smell. Yet, it remains unclear if the damage done by the virus or because it invades immune cells.

Since COVID-19 doesn’t cause nasal congestion, researchers have found a few clues about the loss of smell. Taste receptor cells, which detect chemicals in the saliva and sends signals to the brain do not have ACE receptors. They don’t necessarily  get infected by COVID-19, but other support cells in the tongue carry the receptor.

Researchers determined that more clues on  to how the virus obliterates smell. However, some patients have seen that after five months the ability to smell has returned but not as great as expected. That news is welcomed for patients that have suffered loss of smell due to the COVID-19 virus, yet apprehensions about long term loss of smell is a large cause of concern.

SOURCE

https://www.scientificamerican.com/article/mysteries-of-covid-smell-loss-finally-yield-some-answers1/

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The complication of Pfizer’s Vaccine Distribution’s Plan

Reporter : Irina Robu, PhD

Even though Pfizer announcing the development of safe and effective vaccine is cause for celebration, scientists and public experts face  the challenge of how to quickly make millions of doses of the vaccine and getting them to hospitals, clinics and pharmacies. But Pfizer distribution of vaccines rely on a network of companies, federal and state agencies and on the ground health workers in the midst of a pandemic that is spreading at a high rate in United States.

Before Pfizer can begin shipping its vaccine, federal and state governments must inform Pfizer of how many doses are needed along with syringes, needles and other supplies needed to administer the vaccine. In addition, employees at the locations should be trained to store and administer the vaccine and to ensure that after people are vaccinated, they return for a second dose.

The complication of Pfizer’s vaccine is that it has to be stored at minus 70 degree Celsius until before it is injected.  Pfizer is making the vaccine at facilities in Kalamazoo, Mich., and Puurs, Belgium. The doses distributed in the United States will mostly come from Kalamazoo. When they receive emergency authorization from FDA, Pfizer will send limited doses to large hospitals, pharmacies and other vulnerable groups. At the same time, nine other candidates are also in the final stage of testing.

In Kalamazoo, vaccines will go into vials, vi will go into trays (195 vials per tray) and the trays will go into specially designed cooler-type boxes (up to five trays per box).The reusable boxes, each toting between 1,000 and 5,000 doses and stuffed with dry ice, are equipped with GPS-enabled sensors. Pfizer employees will be able to monitor the boxes’ locations and temperatures as FedEx and UPS transport them to hospitals and clinics nationwide.

The minute Pfizer coolers reach their destinations, hospitals or pharmacies will have a few alternatives of  how to store the vaccine. The easiest option is using ultracold freezers, but they can stash the trays in conventional freezers for up to five days. The destinations can keep the vials in the cooler for up to 15 days as long as they replenish the dry ice and don’t open it more than twice a day.

The chief executives at Pfizer and BioNTech suggest that Pfizer is able to produce up to 50 million doses per year and only half of those will go to US. But since two doses are needed for each person, only 12.5 million doses can be vaccinated.

The other challenge is distributing the vaccine in rural areas, where if not administering the doses fast enough it can go bad. Even though Pfizer has developed and tested an effective vaccine, figuring out how to distribute it is the hardest challenge Pfizer will face.

SOURCE

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12/5/2020

Regeneron’s Covid Antibody coktail has been cleared for emergency use by the FDA. The emergency authorization for REGN-COV2, a combination of monoclonal antibodies casiriviamb and imdevimab, marks the second for the antibody therapy. The first emergency authorization was given to Eli Lily’s bamlanivimab.

The difference that REGN-COV2 is a concoction of several drugs, whereas Lilly’s treatment contains only one drug, the two emergency authorizations  are almost identical. They treat both for mild-to-moderate COVID-19 patients at least 12 years of age who are not hospitalized but are at high risk for progressing to severe COVID-19.

SOURCE

https://www.fiercepharma.com/pharma/regeneron-following-lilly-s-footsteps-wins-fda-emergency-nod-for-covid-19-antibody-cocktail


Regeneron’s new antibody cocktail drug, REGN-COV2

Reporter : Irina Robu, PhD

Regeneron,  leading biotechnology company using the power of science to bring new medicines to patients in need answered quickly to the COVID-19 pandemic and found an antibody cocktail  as the pandemic numbers increase in the U.S. The antibody cocktail, also known as REGN-COV2 antibody combination therapy is an investigational medicine, and its safety and efficacy have not been fully evaluated by any regulatory authority.

REGN-COV2 is being studied in four ongoing late-stage clinical trials: two Phase 2/3 trials for the treatment of hospitalized and non-hospitalized COVID-19 patients, Phase 3 RECOVERY trial of hospitalized COVID-19 patients in the UK, and a Phase 3 trial for the prevention of COVID-19 in uninfected people who are at high-risk of exposure to a COVID-19 patient. The Phase 3 prevention trial is being jointly conducted with the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).

The company expects approval from FDA on its antibody cocktail and expect to have 2.4-gram doses ready for about 80,000 patients at the end of November and 200,000 doses at the beginning of January.  At the same time, Regeneron partnered with Roche to expand its capacity further by increasing its manufacturing capacity.

Regeneron come in COVID-19 research early this year as the outbreak was in its early stages, testing hundreds of virus-neutralizing antibodies in mice and seeing how they compared with antibodies from human survivors of the novel coronavirus.

SOURCE

https://www.fiercepharma.com/manufacturing/regeneron-predicts-300-000-covid-19-cocktail-doses-ready-by-january-and-substantially

 

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From AAAS Science News on COVID19: New CRISPR based diagnostic may shorten testing time to 5 minutes

Reporter: Stephen J. Williams, Ph.D.

 

 

 

 

 

 

 

 

 

A new CRISPR-based diagnostic could shorten wait times for coronavirus tests.

 

 

New test detects coronavirus in just 5 minutes

By Robert F. ServiceOct. 8, 2020 , 3:45 PM

Science’s COVID-19 reporting is supported by the Pulitzer Center and the Heising-Simons Foundation.

 

Researchers have used CRISPR gene-editing technology to come up with a test that detects the pandemic coronavirus in just 5 minutes. The diagnostic doesn’t require expensive lab equipment to run and could potentially be deployed at doctor’s offices, schools, and office buildings.

“It looks like they have a really rock-solid test,” says Max Wilson, a molecular biologist at the University of California (UC), Santa Barbara. “It’s really quite elegant.”

CRISPR diagnostics are just one way researchers are trying to speed coronavirus testing. The new test is the fastest CRISPR-based diagnostic yet. In May, for example, two teams reported creating CRISPR-based coronavirus tests that could detect the virus in about an hour, much faster than the 24 hours needed for conventional coronavirus diagnostic tests.CRISPR tests work by identifying a sequence of RNA—about 20 RNA bases long—that is unique to SARS-CoV-2. They do so by creating a “guide” RNA that is complementary to the target RNA sequence and, thus, will bind to it in solution. When the guide binds to its target, the CRISPR tool’s Cas13 “scissors” enzyme turns on and cuts apart any nearby single-stranded RNA. These cuts release a separately introduced fluorescent particle in the test solution. When the sample is then hit with a burst of laser light, the released fluorescent particles light up, signaling the presence of the virus. These initial CRISPR tests, however, required researchers to first amplify any potential viral RNA before running it through the diagnostic to increase their odds of spotting a signal. That added complexity, cost, and time, and put a strain on scarce chemical reagents. Now, researchers led by Jennifer Doudna, who won a share of this year’s Nobel Prize in Chemistry yesterday for her co-discovery of CRISPR, report creating a novel CRISPR diagnostic that doesn’t amplify coronavirus RNA. Instead, Doudna and her colleagues spent months testing hundreds of guide RNAs to find multiple guides that work in tandem to increase the sensitivity of the test.

In a new preprint, the researchers report that with a single guide RNA, they could detect as few as 100,000 viruses per microliter of solution. And if they add a second guide RNA, they can detect as few as 100 viruses per microliter.

That’s still not as good as the conventional coronavirus diagnostic setup, which uses expensive lab-based machines to track the virus down to one virus per microliter, says Melanie Ott, a virologist at UC San Francisco who helped lead the project with Doudna. However, she says, the new setup was able to accurately identify a batch of five positive clinical samples with perfect accuracy in just 5 minutes per test, whereas the standard test can take 1 day or more to return results.

The new test has another key advantage, Wilson says: quantifying a sample’s amount of virus. When standard coronavirus tests amplify the virus’ genetic material in order to detect it, this changes the amount of genetic material present—and thus wipes out any chance of precisely quantifying just how much virus is in the sample.

By contrast, Ott’s and Doudna’s team found that the strength of the fluorescent signal was proportional to the amount of virus in their sample. That revealed not just whether a sample was positive, but also how much virus a patient had. That information can help doctors tailor treatment decisions to each patient’s condition, Wilson says.

Doudna and Ott say they and their colleagues are now working to validate their test setup and are looking into how to commercialize it.

Posted in:

doi:10.1126/science.abf1752

Robert F. Service

Bob is a news reporter for Science in Portland, Oregon, covering chemistry, materials science, and energy stories.

 

Source: https://www.sciencemag.org/news/2020/10/new-test-detects-coronavirus-just-5-minutes

Other articles on CRISPR and COVID19 can be found on our Coronavirus Portal and the following articles:

The Nobel Prize in Chemistry 2020: Emmanuelle Charpentier & Jennifer A. Doudna
The University of California has a proud legacy of winning Nobel Prizes, 68 faculty and staff have been awarded 69 Nobel Prizes.
Toaster Sized Machine Detects COVID-19
Study with important implications when considering widespread serological testing, Ab protection against re-infection with SARS-CoV-2 and the durability of vaccine protection

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Online Event: Vaccine matters: Can we cure coronavirus? An AAAS Webinar on COVID19: 8/12/2020

Reporter: Stephen J. Williams. PhD

Source: Online Event

Top on the world’s want list right now is a coronavirus vaccine. There is plenty of speculation about how and when this might become a reality, but clear answers are scarce.Science/AAAS, the world’s leading scientific organization and publisher of the Science family of journals, brings together experts in the field of coronavirus vaccine research to answer the public’s most pressing questions: What vaccines are being developed? When are we likely to get them? Are they safe? And most importantly, will they work?

link: https://view6.workcast.net/AuditoriumAuthenticator.aspx?cpak=1836435787247718&pak=8073702641735492

Presenters

Presenter
Speaker: Sarah Gilbert, Ph.D.

University of Oxford
Oxford, UK
View Bio

Presenter
Speaker: Kizzmekia Corbett, Ph.D.

National Institute of Allergy and Infectious Diseases, NIH
Bethesda, MD
View Bio

Presenter
Speaker: Kathryn M. Edwards, M.D.

Vanderbilt Vaccine Research Program
Nashville, TN
View Bio

Presenter
Speaker: Jon Cohen

Science/AAAS
San Diego, CA
View Bio

Presenter
Moderator: Sean Sanders, Ph.D.

Science/AAAS
Washington, DC
View Moderator Bio

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via Dr. Giordano Featured in Forbes Article on COVID-19 Antibody Tests in Italy and USA

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