Category: Uncategorized

New Book on CRISPR Gene-editing Technology

A new book, “Editing Humanity: The Crispr Revolution and the New Era of Genome Editing”, by Kevin Davies lays out the story that led to developing the revolutionary CRISPR gene-editing technology.

It describes the development of the technology involved clearly and succinctly, from the beginnings of gene sequencing to the 2012 discovery that an ancient bacterial immune system could be adapted and become the basis of the CRISPR gene-editing technology.

It also describes the misuse of the technology, such as with early gene therapy being done outside of the US on girls and young women to avoid US oversight. And despite a 2015 consensus that human sperm, eggs or embryos should not be edited, a scientist announced in 2018 that he had used gene editing on a pair of twin girls to confer HIV protection. 

The book however does not address how ethical issues should be resolved, such as releasing genetically engineered mosquitoes into the environment to suppress malaria.

Source: Nature

Inflammatory Foods Raise Cardiovascular Risk

A pair of studies have examined the effect that the dietary inflammatory index has on cardiovascular health, and found that inflammatory foods increase cardiovascular risk.

It is known that inflammatory biomarkers such as interleukins, chemokines and adhesion molecules are associated with atherosclerosis, and proinflammatory foods such as red meats are also associated with cardiovascular risk. The study examined 210 000 participants over 32 years, who filled out a dietary survey every four years, and controlled for variables such as overweight.

“Using an empirically-developed, food-based dietary index to evaluate levels of inflammation associated with dietary intake, we found that dietary patterns with higher inflammatory potential were associated with an increased rate of cardiovascular disease,” said Jun Li, MD, Ph.D., lead author of the study and research scientist in the department of nutrition at Harvard T.H. Chan School of Public Health. “Our study is among the first to link a food-based dietary inflammatory index with long-term risk of cardiovascular disease.”

The other study looked at the beneficial effects of walnuts, which have a strong anti-inflammatory effect. Participants who were assigned to eat 30-60gm of walnuts a day showed significantly reduced inflammation in 6 of 10 biomarkers used.

“The anti-inflammatory effect of long-term consumption of walnuts demonstrated in this study provides novel mechanistic insight for the benefit of walnut consumption on heart disease risk beyond that of cholesterol lowering,” said Montserrant Cofán, Ph.D., lead author of the study and a researcher at the August Pi i Sunyer Biomedical Research Institute in Barcelona, Spain.

Source: Medical Xpress

Brain Swelling Has an Unexpected Protective Effect

Animal studies have shown that swelling in the brain can protect it in the longer term. Dangerous brain activity can take place after a brain injury (such as from blunt trauma), where neural network activity can surge to dangerous levels, resulting in seizures and tissue injury for months or years after the original injury. Swelling may reduce this long-term effect, an unexpected protective benefit.

At the University of Utah, Punam Sawant-Pokam, PhD, and KC Brennan, MD, investigated the effects of cerebral injury and swelling. They examined the brains of mice subjected to injury with a range of advanced tools for brain recording and electrical activity, 

When observations were made 48 hours after injury, when maximum swelling usually appears, untreated mice brains showed swollen neurons but their neuronal activity had surprisingly dropped. Mice that were given drugs to reduce swelling showed that the neurons continued to show over-activity.

“This data prompts a pretty big reconsideration of how we view edema after brain injury,” Brennan said. “When oedema is about to cause death, it is the number one priority. We’re not saying this is not true. But we’re opening up more nuance to the phenomenon in a way that might allow us to eventually get to more specific treatments and better outcomes.

“It’s very exciting to know that neuronal oedema is not only reducing cellular excitability, it’s also protecting the brain from dangerous network events,” Sawant-Pokam said.

The findings suggest that patients could benefit from more targeted approaches to dealing with cerebral oedema.

Source: Medical Xpress

Healthy Country Childhood: The Protective “Farm Effect” on Asthma

The presence of a diverse gut microbiome appears to exert a protective effect against asthma, which may explain the largely protective “farm effect” on asthma.

European researchers analysed faecal samples from over 700 infants raised on farms, and found a strong environmental effect. It was anticipated that nutrition would be a strong contributor to gut microbiome maturation, but there were unanticipated environmental effects such as exposure to animal sheds.

Researchers found that faecal butyrate (related to butyrate, a short-chain fatty acid), which is already known to protect against asthma in mice, had an inverse association with asthma. They ascribed this to gut bacteria such as Roseburia and Coprococcus which have the potential of producing short chain fatty acids. Children with more matured gut microbiomes had Roseburia and Coprococcus present.

“Our study provides further evidence that the gut may have an influence on the health of the lung. A mature gut microbiome with a high level of short chain fatty acids had a protective effect on the respiratory health of the children in this study. This suggests the idea of a relevant gut-lung axis in humans,” said Dr. Markus Ege, professor for clinical-respiratory epidemiology at the Dr. von Hauner Children’s Hospital. “This also means, however, that an immature gut microbiome may contribute to the development of diseases. This emphasizes the need for prevention strategies in the first year of life, when the gut microbiome is highly plastic and amenable to modification.”

Source: News-Medical.Net

Extreme “Super-spreader” Events Boost COVID Spread

The SARS-CoV-2 virus has a reproduction number of three, indicating that on average it will infect three other individuals over the course of the infection. However, a study at the Massachusetts Institute of Technology (MIT) found that extreme “super-spreader” events, such as the one that happened at a White House event in September, seem to generate more infections than would otherwise be expected due to random distributions.

“Super-spreading events are likely more important than most of us had initially realized. Even though they are extreme events, they are probable and thus are likely occurring at a higher frequency than we thought. If we can control the super-spreading events, we have a much greater chance of getting this pandemic under control,” said James Collins, the Termeer Professor of Medical Engineering and Science in MIT’s Institute for Medical Engineering and Science (IMES) and Department of Biological Engineering, and the senior author of this study. 

The researchers analysed a number of documented “super-spreader events” that have taken place over the COVID pandemic. When they ran statistical analyses on super-spreader events, they found that instead of the expected “bell curve” of normal distribution, they found a “fat tail” of extreme events.

Lead author, MIT postdoc Felix Wong said, “This means that the probability of extreme events decays more slowly than one would have expected. These really large super-spreading events, with between 10 and 100 people infected, are much more common than we had anticipated.”

Source: Medical Xpress

UV Key to Seasonality of Airborne Respiratory Diseases

It has long been observed that flu seasons in the northern hemisphere tend to last over autumn and winter, while in regions closer to the equator, they tend to have a year-round prevalence.

A group of Italian researchers believe that the sun – specifically its UV rays, which are known to inactivate various pathogens – holds the key. This periodic change in UV radiation over the seasons resonates with another cyclical event – the loss of resistance in the host over half a year of antigenic drift. The researchers incorporated these effects into a series of models, which reflect the seasonality of airborne respiratory diseases.

“From an epidemiologic point of view, these models clarify an important and long-standing mystery: why do influenza epidemics disappear every year when the number of susceptible individuals is still very far from that needed to trigger the herd immunity mechanism?” said Mario Clerici, Immunologist at the University of Milan and the Don Gnocchi Foundation.
“The Italian data of the SARS-CoV-2 pandemics can also be described accurately by our model,” said Fabrizio Nicastro, INAF researcher and PI of the work, “but the predictive power of the model depends critically (other than on the implementation of new restriction measures) on the exact UV-B/A lethal doses for the COVID-19 virus, which our collaboration is about to measure.”

Source: Medical Xpress

Speech Recognition AI Detects COVID in Coughs

An AI system originally developed at the Massachusetts Institute of Technology (MIT) to research speech patterns in people with Alzheimer’s was repurposed when the COVID pandemic hit to become an indicator for COVID in asymptomatic patients. 

“The sounds of talking and coughing are both influenced by the vocal cords and surrounding organs,” says research scientist Brian Subirana of MIT.
“This means that when you talk, part of your talking is like coughing, and vice versa. It also means that things we easily derive from fluent speech, AI can pick up simply from coughs, including things like the person’s gender, mother tongue, or even emotional state. There’s in fact sentiment embedded in how you cough.”

The system was based on a neural network that was trained on a thousand hours of human speech, then on a database on words spoken in different emotional states and finally a database of coughs. The result was a system that could detect a cough in an asymptomatic person with COVID with 97.1% accuracy. However, this is not a true test of COVID but an enhanced early indicator. The advantage of this technology is that it can be developed as an early warning system that can be incorporated into something as ubiquitous as a smartphone.

Source: Science Alert

COVID DNA of White House “Superspreader Event” Analysed

On September 26, numerous high-profile individuals, contracted COVID at a large official White House gathering. This White House “superspreader event” as it was known became something of a case study in how COVID can spread in large groups of people.

Although President Trump contracted the virus, it is not known if this was a result of attending that event. The event, which had over a dozen guests, resulted in 34 individuals including White House staff testing positive for COVID by October 7.

Whilst contact tracing is difficult with COVID, genome sequencing offers a chance for insights into its development and spread. The researchers analysed SARS-CoV-2 genomes from nasal swabs taken from the patients at the White House superspreader event, and analysed it, looking for mutations. They found two variants, WH-2 and WH-2. They determined that these viruses descended from those widely in circulation in Florida, New York, Texas, Connecticut, and Washington – as well as certain countries such as  New Zealand.

Source: News-Medical.Net

Hypertension at Night Raises Cardiovascular Disease Risk

An eight year long study conducted in Japan added to the evidence that hypertension during the night raises cardiovascular disease risk, especially compared to the daytime. 

Hypertension levels are usually assessed during the day, and do not give an accurate snapshot of a person’s circadian rhythm.  According to lead author of the study, Kazuomi Kario, MD, PhD, hypertension at night, especially when blood pressure is lower during the day, raises cardiovascular disease risk and is increasingly being recognised as a risk factor. Kario said, “This study provides much more in-depth information about the cardiovascular risk associated with high nighttime blood pressure and different nighttime blood pressure phenotypes than have been reported previously.”

The Japan Ambulatory Blood Pressure Monitoring Prospective (JAMP) study enrolled 6359 patients and measured daytime and nighttime levels using an at-home, wearable, ambulatory monitor. They were told to conduct their daily routine as normal, and to rest or sleep during the night. The results showed that elevated blood pressure during the night compared to the day was a significant indicator of raised cardiovascular disease risk. Patients who were hypertensive and then had a large dip in systolic pressure had a greater risk for stroke.

“Results indicate that nighttime systolic blood pressure was a significant, independent risk factor for cardiovascular events,” said Dr Kario. “The study highlights the importance of including nighttime blood pressure monitoring in patient management strategies and will hopefully encourage physicians to ensure that antihypertensive therapy is effectively lowering blood pressure throughout the 24-hour dosing period.”

Source: Medical Xpress

Research Suggests Vitamin C Beneficial for Severe COVID

According to Associate Professor Anitra Carr of Otago University in New Zealand, research provides evidence that large doses of Vitamin C is beneficial for severe COVID. A 2019 study previously showed that giving Vitamin C to patients with Acute Respiratory Distress reduced mortality rates.

“A recent study that came out of the US showed that patients with coronavirus in ICU with Covid-19 also had very low vitamin C levels,” Carr said. “That’s because the body chews through a lot more of it when you get an infection – and your requirements increase significantly. But the standard doses given in the intensive care unit aren’t enough to compensate, given a severe case of the disease comes with a huge inflammatory response and oxidative stress.”

 Carr said that delivering the drug intravenously was critical to supplying the high levels of Vitamin C needed. One study from Wuhan, China showed Vitamin C conferred a survival benefit to placebo, though Carr noted that many more studies are needed and will come throughout the next year.

However, besides its normal dietary role, there was little research to show that Vitamin C had much of a preventative role. Carr said, “Some research has shown that, if you’re under enhanced stress, your risk for infection increases, so in those people vitamin C may decrease the risk of getting it. But in the general everyday population, who aren’t under extreme physical stress, it may not decrease your chances of catching the disease.”

Source: NZ Herald