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Comment by Dr. Krishna Kumari Challa on March 4, 2022 at 8:42am

Discovery may explain why more females than males get knee osteoarthritis

Knee osteoarthritis is the most common joint problem, affecting an estimated 250 million people worldwide, including 14 per cent of females older than 60 and 10 per cent of males in the same age group.

Female astronauts could avoid knee injuries during space flight — and better tests, prevention and treatments could be developed for knee osteoarthritis in women here on Earth — based on newly published research on the sex differences in knee meniscus tissue.

Knee osteoarthritis is more common in females than in males, but hormones alone are not enough to explain the difference. The new research identifies a genetic difference in the meniscus that makes about 50 per cent of females more vulnerable to developing osteoarthritis than males or other females.

Researchers carried out the experiments in part by simulating low-gravity conditions in space, which mimics the damage that can happen to the meniscus due to lack of exercise.

Some of the genes that were found in the females that responded more to simulated space microgravity were also associated with the development of knee osteoarthritis.

Meniscus is a kind of cartilage in the knee that acts as a load distributor for the body’s full weight. At one time, it was thought to be like the appendix: you wouldn’t miss it if it were gone. But now it’s known that just a small tear in the meniscus — usually caused by a sports injury — increases the risk of osteoarthritis later in life, even if the damaged tissue has been removed.

On the other hand, lack of use can also lead to deconditioning of the meniscus and increase arthritis risk. You’ll notice the short-term effect of deconditioning when you get out of bed in the morning and feel stiff, but then your joints loosen up once you’ve moved around for a while. It’s the same thing that happens to astronauts in space, unless they use specially designed resistance equipment to make up for the lack of weight-bearing exercise in microgravity.

Zhiyao Ma et al, Engineered Human Meniscus in Modeling Sex Differences of Knee Osteoarthritis in Vitro, Frontiers in Bioengineering and Biotechnology (2022). DOI: 10.3389/fbioe.2022.823679

https://researchnews.cc/news/11920/Discovery-may-explain-why-more-f...

Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 11:34am

This statistical model provides a basis for accommodating what has previously been a thorn in the side of theorists such as Darwin.

Darwin's theory of evolution by natural selection predicts gradual and incremental changes to organisms occurring over very long timespans. But the fossil record  frequently shows very abrupt changes in the sizes, shapes, colors and other features of organisms, and these have been used for at least fifty years to challenge the Darwinian orthodoxy.

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Many of these abrupt changes occurred around 60-70 million years ago, a period that saw the rise of many different mammal groups from earlier forms. For example, over a 100,000 year period an early small grazing animal (Conacodon entoconus), ancestral to today's modern cows, antelopes, and giraffes, increased in size over 70-fold. More recently, the baleen whales (e.g., humpback, blue and sperm whales) have increased over 100-fold in size from a small dolphin-like ancestor in the same amount of time (~ 7 million years) that separates modern humans from their common ancestor with the chimpanzees.

General statistical model shows that macroevolutionary patterns and processes are consistent with Darwinian gradualism, Nature Communications (2022). DOI: 10.1038/s41467-022-28595-z

https://phys.org/news/2022-03-gradual-evolution-darwinian-theory.ht...

Researchers show in this paper that even these abrupt changes are easily explained as cases of what is known as 'directional selection'—when natural selection strongly pulls a trait in one direction. No special extra-Darwinian mechanisms are required.

Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 11:27am

Gradual evolution is back: Darwinian theory of gradual process explained in new research

Abrupt shifts in the evolution of animals—short periods of time when an organism rapidly changes size or form—have long been a challenge for theorists including Darwin. Now a newly published research paper supports the idea that even these abrupt changes are underpinned by a gradual directional process of successive incremental changes, as Darwin's theory of evolution assumes.

Published in Nature Communications recently, evolutionary biologists propose a new statistical model which seeks to explain these sudden changes and long periods of stasis that have been seen in the evolutionary history of some species.

Researchers developed a statistical model that reconstructed the body-size changes which occurred throughout the 170-million-year history of more than 2800 mammal species.

The authors found that despite there being periods for some mammals during which abrupt changes in size occur, these occurrences can be understood as 'normal' changes that draw on the natural variability that evolution routinely adds to natural populations.

Part 1

Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 11:18am

Cas9 protein redesigned to make 

Gene editing safer

One of the grand challenges with using CRISPR-based gene editing on humans is that the molecular machinery sometimes makes changes to the wrong section of a host's genome, creating the possibility that an attempt to repair a genetic mutation in one spot in the genome could accidentally create a dangerous new mutation in another.

CRISPR-based gene-editing tools are adapted from naturally occurring systems in bacteria. In nature, a Cas9 protein floats around in the environment, searching for DNA with a very specific sequence of 20 letters, like the X on a pirate map that indicates "dig here." Sometimes, when most of the letters are correct, except those in spots 18 through 20, Cas9 still goes ahead and digs in. This is called a mismatch, and it can have disastrous consequences in gene editing.

But now, scientists  have redesigned a key component of a widely used CRISPR-based gene-editing tool, called Cas9, to be thousands of times less likely to target the wrong stretch of DNA while remaining just as efficient as the original version, making it potentially much safer. The work is described in a paper published today in the journal Nature.

So far, the researchers have demonstrated the use of SuperFi-Cas9 on DNA in test tubes. They're now collaborating with other researchers who plan to test SuperFi-Cas9 for gene editing in living cells. They're also working to develop still safer and more active versions of Cas9.

David Taylor, Structural basis for mismatch surveillance by CRISPR–Cas9, Nature (2022). DOI: 10.1038/s41586-022-04470-1. www.nature.com/articles/s41586-022-04470-1

https://phys.org/news/2022-03-gene-safer-redesigned-cas9-protein.ht...

Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 8:41am

No, you cannot ‘devaccinate’ yourself with snake venom kits, bleach or cupping

Claims you can “devaccinate” yourself have been circulating on social media, another example of extreme and dangerous misinformation about COVID vaccines.

Methods said to remove COVID vaccines from the body include using snake venom extractors or a type of traditional therapy known as “wet cupping”.

If you encounter claims like this online, you need to ask yourself four questions, to figure out whether these claims really are too good to be true.

https://theconversation.com/no-you-cannot-devaccinate-yourself-with...

Comment by Dr. Krishna Kumari Challa on March 2, 2022 at 11:26am

 “Vigyan Sarvatra Pujyate”  = Science is revered everywhere

Comment by Dr. Krishna Kumari Challa on March 2, 2022 at 10:02am

Solar panels developed to pull in water vapour to grow crops in the desert

Using a unique hydrogel, scientists created a solar-driven system that successfully grows spinach by using water drawn from the air while producing electricity. The proof-of-concept design, described March 1 in the journal Cell Reports Physical Science, offers a sustainable, low-cost strategy to improve food and water security for people living in dry-climate regions.

The system, called WEC²P, is composed of a solar photovoltaic panel placed atop a layer of hydrogel, which is mounted on top of a large metal box to condense and collect water. The researchers  developed the hydrogel in their prior research, and the material can effectively absorb water vapour from ambient air and release the water content when heated.

The researchers used the waste heat from solar panels when generating electricity to drive absorbed water out of the hydrogel. The metal box below collects the vapor and condenses the gas into water. Alternatively, the hydrogel increases the efficiency of solar photovoltaic panels by as much as 9% by absorbing the heat and lowering the panels' temperature.

Peng Wang, An Integrated Solar Driven System Produces Electricity with Freshwater and Crops in Arid Regions, Cell Reports Physical Science (2022). DOI: 10.1016/j.xcrp.2022.100781. www.cell.com/cell-reports-phys … 2666-3864(22)00048-0

https://techxplore.com/news/2022-03-solar-panels-vapor-crops.html?u...

Comment by Dr. Krishna Kumari Challa on March 2, 2022 at 9:15am

New epigenetic biomarkers found that potentially predict preterm birth

A signature found in the cheek cells of mothers and fathers of preterm infants may help develop a test to determine whether a pregnancy may end too early. Such a test could help prevent premature births and the many resulting health impacts on infants by alerting medical providers to the need for early intervention measures.

In a study published in Scientific Reports on March 1, researchers documented more than 100 epigenetic biomarkers in mothers of preterm babies that were distinct from mothers of babies carried to term. Fathers had fewer biomarkers but enough to indicate a likely paternal role in preterm birth.

The signature they found was present in all the parents they analyzed. This is likely to lead eventually to a very useful test. They used buccal cells, which are collected by a cheek swab. It's very non-invasive and easy to do.

Epigenetics are molecular factors and processes around DNA that determine how genes behave. While independent of DNA sequence, epigenetic modifications, which can be caused by things such as toxicant exposure, poor nutrition and alcohol use, can also be inherited.

In this study, researchers found that the preterm female babies carried more than 100 of these biomarkers, indicating the propensity to have a preterm baby may be passed down. That transgenerational capacity is also supported by the fact the signature is found in cheek cells. If an epigenetic modification is present in both sperm and ovum, the resulting baby will have that modification present in every cell of their body—including their cheek cells.

 Preterm birth buccal cell epigenetic biomarkers to facilitate preventative medicine, Scientific Reports (2022). DOI: 10.1038/s41598-022-07262-9

https://medicalxpress.com/news/2022-03-epigenetic-biomarkers-potent...

Comment by Dr. Krishna Kumari Challa on March 1, 2022 at 10:57am

What If We Have A Nuclear War?

Comment by Dr. Krishna Kumari Challa on March 1, 2022 at 10:52am

Climate change is outpacing adaptation

Rising greenhouse-gas emissions could soon outstrip the ability of many communities to adapt. A report from the United Nations Intergovernmental Panel on Climate Change (IPCC), authored by more than 270 researchers from 67 countries, finds that the negative impacts of climate change are mounting far faster than.... Many effects are unavoidable and will hit the world’s most vulnerable populations hardest, it warns. “Any further delay in global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a livable and sustainable future for all,” says climate scientist and co-author Maarten van Aalst.

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