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Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 9:15am

Genes that dance to the circadian rhythm

Scientists  have made breakthrough discoveries on the circadian clock and how it affects gene expression. Some of the findings suggest a biological underpinning for different behaviors in people, such as morning people, nappers, evening people, night owls etc.

The study of circadian rhythms has grown into its own field: chronobiology. And given that a person's circadian rhythm seems to dictate when certain drugs must be taken in order to maximize their effects, a new branch of medicine has also emerged recently: chronopharmacology.

 Now scientists have carried out an extensive study using Drosophila to study how different genes in various tissues of the animal are regulated so that they "know" when to turn on and off during the course of a day, i.e. in function of the circadian clock.

The study revealed three major points about the circadian rhythm.

First, the scientists detected more than 1700 genes whose expression cycles under the control of the circadian clock, with only fourteen of those genes being the same across all tissues in the fruit fly.

"At least two of these fourteen were so far uncharacterized and significantly impact several locomotor activity rhythms parameters.

Second, that each individual may have its own circadian rhythm, which may explain the large range of human behaviors, such as morning people, nappers, evening people, night owls etc.

The physiological clock in about a third of Drosophila lines significantly deviates from the "natural" time by more than three hours. And most of the lines showed a circadian expression variation only in one or two tissues.

There seems to be an abundant, natural circadian asynchrony in molecular circadian rhythms between various tissues, which has to our knowledge not been observed before and which may have all kinds of physiological consequences in metabolic patterns, digestive fluctuations etc.

Finally, that a small genetic mutation can disrupt an individual's "photoentrainment," which refers to the aligning of the circadian rhythm to the pattern of light and dark in its environment.

"Extensive tissue-specific expression variation and novel regulators underlying circadian behavior" Science Advances, advances.sciencemag.org/lookup … .1126/sciadv.abc3781

https://phys.org/news/2021-01-genes-circadian-rhythm.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 9:07am

New technology to detect bitter almonds in real time

Who hasn't at some point been chewing on an almond and tasted an unpleasant and unexpected aftertaste that has nothing to do with the taste we are used to from one of the most consumed nuts in the world? The culprit has a name: amygdalin, a diglucoside that, when in contact with enzymes present in saliva, breaks down into glucose, benzaldehyde (the cause of the bitter taste) and hydrogen cyanide.

To reduce this unpleasant ''surprise," researchers have developed a method that can predict levels of the abovementioned amygdalin present in the nuts analyzed both with and without shells, as well as correctly classify sweet almonds and bitter ones on an industrial scale, something that has only been done with shelled nuts, individual kernels or ground nuts to date.

The new system uses portable equipment based on near infrared spectroscopy (NIRS) technology, which can analyze large amounts of a product in situ in real time, without having to go into a lab. This technological application is "of great interest to the farming sector.

This technology is especially useful in the early detection of possible fraud and in food authentication.

Miguel Vega-Castellote et al, Exploring the potential of NIRS technology for the in situ prediction of amygdalin content and classification by bitterness of in-shell and shelled intact almonds, Journal of Food Engineering (2020). DOI: 10.1016/j.jfoodeng.2020.110406

https://phys.org/news/2021-01-technology-bitter-almonds-real.html?u...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 9:02am

Accurate drug dosages with proton traps

Researchers have developed a proton trap that makes organic electronic ion pumps more precise when delivering drugs. The new technique may reduce drug side effects, and in the long term, ion pumps may help patients with symptoms of neurological diseases for which effective treatments are not available. The results have been published in Science Advances.

Currently available drug delivery methods—mainly tablets and injections—place the drug in locations where it is not required. This can lead to side effects that harm the patient.

Researchers are trying to control this. Recent discovery in this regard is a proton trap that makes the amount delivered even more precise.

"An electronic proton-trapping ion pump for selective drug delivery" Science Advances, advances.sciencemag.org/lookup … .1126/sciadv.abd8738

https://phys.org/news/2021-01-accurate-drug-dosages-proton.html?utm...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 8:51am

Dewdrops on a spiderweb reveal the physics behind cell structures

As any cook knows, some liquids mix well with each other, but others do not. For example, when a tablespoon of vinegar is poured into water, a brief stir suffices to thoroughly combine the two liquids. However, a tablespoon of oil poured into water will coalesce into droplets that no amount of stirring can dissolve. The physics that governs the mixing of liquids is not limited to mixing bowls; it also affects the behavior of things inside cells. It's been known for several years that some proteins behave like liquids, and that some liquid-like proteins don't mix together. However, very little is known about how these liquid-like proteins behave on cellular surfaces.

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How vitamins, steroids and potential antivirals might affect SARS-C...

Evidence is emerging that vitamin D—and possibly vitamins K and A—might help combat COVID-19. A new study from the University of Bristol published in the journal of the German Chemical Society Angewandte Chemie has shown how they—and other antiviral drugs—might work. The research indicates that these dietary supplements and compounds could bind to the viral spike protein and so might reduce SARS-CoV-2 infectivity. In contrast, cholesterol may increase infectivity, which could explain why having high cholesterol is considered a risk factor for serious disease.

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It's elemental: Ultra-trace detector tests gold purity

Unless radon gas is discovered in a home inspection, most people remain blissfully unaware that rocks like granite, metal ores, and some soils contain naturally occurring sources of radiation. In most cases, low levels of radiation are not a health concern. But some scientists and engineers are concerned about even trace levels of radiation, which can wreak havoc on sensitive equipment. The semiconductor industry, for instance, spends billions each year to source and "scrub" ultra-trace levels of radioactive materials from microchips, transistors and sensitive sensors.

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How lipids distribute proteins within cells

Researchers have observed how lipids distribute proteins within cells, a discovery that could open the door to understanding the causes of protein transport related diseases, such as cancer or neurodegenerative diseases.

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 8:50am

By changing their shape, some bacteria can grow more resilient to antibiotics

New research demonstrates how certain types of bacteria can adapt to long-term exposure to antibiotics by changing their shape. The work was published in the journal Nature Physics.

Adaptation is a fundamental biological process driving organisms to change their traits and behaviour to better fit their environment. While antibiotics have long helped people prevent and cure bacterial infections, many species of bacteria have increasingly been able to adapt to resist antibiotic treatments.

When exposed to less than lethal doses of the antibiotic chloramphenicol over multiple generations, the researchers found that the bacteria dramatically changed their shape by becoming wider and more curved.

These shape changes enable bacteria to overcome the stress of antibiotics and resume fast growth. 

The researchers came to this conclusion by developing a theoretical model to show how these physical changes allow the bacteria to attain a higher curvature and lower surface-to-volume ratio, which would allow fewer antibiotic particles to pass through their cellular surfaces as they grow.

This insight is of great consequence to human health and will likely stimulate numerous further molecular studies into the role of cell shape on bacterial growth and antibiotic resistance.

Shiladitya Banerjee et al. Mechanical feedback promotes bacterial adaptation to antibiotics, Nature Physics (2021). DOI: 10.1038/s41567-020-01079-x

https://phys.org/news/2021-01-bacteria-resilient-antibiotics.html?u...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 8:42am

'Organs-on-a-chip' system sheds light on how bacteria in the human digestive tract may influence neurological diseases

In many ways, our brain and our digestive tract are deeply connected. Feeling nervous may lead to physical pain in the stomach, while hunger signals from the gut make us feel irritable. Recent studies have even suggested that the bacteria living in our gut can influence some neurological diseases.

Modeling these complex interactions in animals such as mice is difficult to do, because their physiology is very different from humans'. To help researchers better understand the gut-brain axis, MIT researchers have developed an "organs-on-a-chip" system that replicates interactions between the brain, liver, and colon.

Using that system, the researchers were able to model the influence that microbes living in the gut have on both healthy brain tissue and tissue samples derived from patients with Parkinson's disease. They found that short-chain fatty acids, which are produced by microbes in the gut and are transported to the brain, can have very different effects on healthy and diseased brain cells.

"While short-chain fatty acids are largely beneficial to human health, it 's observed that under certain conditions they can further exacerbate certain brain pathologies, such as protein misfolding and neuronal death, related to Parkinson's disease.

The brain has many interactions with the digestive tract, which can occur via the enteric nervous system or through the circulation of immune cells, nutrients, and hormones between organs.

"Human hysiomimetic model integrating microphysiological systems of the gut, liver and brain for studies of neurodegenerative diseases" Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abd1707

https://medicalxpress.com/news/2021-01-organs-on-a-chip-bacteria-hu...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 8:37am

A potentially safer, more effective gene therapy vector for blood disorders

Researchers at Children's Hospital of Philadelphia (CHOP) have developed a gene therapy vector for blood disorders like sickle cell disease and beta-thalassemia that is potentially safer and more effective than those currently used in gene therapy trials for those conditions. The vector, an engineered vehicle for delivering functional copies of the hemoglobin gene to correct a genetic abnormality, leads to the production of more hemoglobin with a lower dose, minimizing the risk of toxic side effects.

Breda L, Ghiaccio V, Tanaka N, Jarocha D, Ikawa Y, Abdulmalik O, Dong A, Casu C, Raabe TD, Shan X, Danet-Desnoyers GA, Doto AM, Everett J, Bushman FD, Radaelli E, Assenmacher CA, Tarrant JC, Hoepp N, Guzikowski V, Smith-Whitley K, Kwiatkowski JL, and Rivella S. "Lentiviral vector ALS20 yields high hemoglobin levels with low genomic integrations for treatment of beta-globinopathies," Molecular Therapy, online January 29, 2021. DOI: 10.1016/j.ymthe.2020.12.036

https://medicalxpress.com/news/2021-01-potentially-safer-effective-...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 8:35am

Threads that sense how and when you move? New technology makes it possible

Engineers at Tufts University have created and demonstrated flexible thread-based sensors that can measure movement of the neck, providing data on the direction, angle of rotation and degree of displacement of the head. The discovery raises the potential for thin, inconspicuous tatoo-like patches that could, according to the Tufts team, measure athletic performance, monitor worker or driver fatigue, assist with physical therapy, enhance virtual reality games and systems, and improve computer generated imagery in cinematography. The technology, described today in Scientific Reports, adds to a growing number of thread-based sensors developed by Tufts engineers that can be woven into textiles, measuring gases and chemicals in the environment or metabolites in sweat.

Scientific Reports (2021). DOI: 10.1038/s41598-021-81284-7

https://techxplore.com/news/2021-01-threads-technology.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 8:28am

'Weak' and 'strong' cells bonding boosts body's diabetes fight

Scientists have broadened our understanding of how 'weak' cells bond with their more mature cellular counterparts to boost the body's production of insulin, improving our knowledge of the processes leading to type 2 diabetes—a significant global health problem.

Type 2 diabetes mellitus occurs when β-cells cannot release enough insulin—a tightly controlled process requiring hundreds of such cells clustered together to co-ordinate their response to signals from food, such as sugar, fat and gut hormones.

Now an international research team have discovered that immature β-cells (PDX1LOW/MAFALOW) are able to overcome their relative deficiencies by partnering with 'stronger' counterparts to drive insulin release.  The researchers reveal that subtle differences in the levels of PDX1 and MAFA proteins (found only in β-cells) , and more broadly, differences in β-cell maturity, contribute to how clusters of insulin-producing cells, known as islets, function. 

The study shows that differences in β-cell maturity, defined using PDX1 and MAFA levels, are needed across the islet for proper insulin release. Unexpectedly, increases in the proportion of mature β-cells, is associated with islet failure. It seems that, rather like society, the islet needs cells with all ages to be properly functional.

Redressing the balance between immature and mature β-cells restores islet function under conditions of metabolic stress—an excess of sugar and fat in the diet—providing evidence that both 'weak' and 'strong' β-cells could contribute to proper islet function and insulin release.

"This is the first glimpse that immature cells might contribute to the regulation of insulin release across the islet. The study indicates a promising line of investigation that could be leveraged to make islets more resilient during type 2 diabetes or when generating new islets in a 'dish' for the purpose of transplantation."

'PDX1LOW MAFALOW β-cells contribute to islet function and insulin release' Daniela Nasteska, Nicholas H. F. Fine, Fiona B. Ashford, Federica Cuozzo, Katrina Viloria, Gabrielle Smith, Aisha Dahir, Peter W. J. Dawson, Yu-Chiang Lai, Aimée Bastidas-Ponce, Mostafa Bakhti, Guy A. Rutter, Remi Fiancette, Rita Nano, Lorenzo Piemonti, Heiko Lickert, Qiao Zhou, Ildem Akerman and David J. Hodson is published in Nature Communications. DOI: 10.1038/s41467-020-20632-z

https://medicalxpress.com/news/2021-01-weak-strong-cells-bonding-bo...

Comment by Dr. Krishna Kumari Challa on January 30, 2021 at 7:55am

Specific bacteria in the gut prompt mother mice to neglect their pups

As scientists learn more about the microorganisms that colonize the body—collectively called the microbiota—one area of intense interest is the effect that these microbes can have on the brain. A new study led by Salk Institute scientists has identified a strain of E. coli bacteria that, when living in the guts of female mice, causes them to neglect their offspring.

The findings show  a direct link between a particular microbe and maternal behavior. Although the research was done in mice, it adds to the growing body of science demonstrating that microbes in the gut are important for brain health and can affect development and behaviour.

 this is the first demonstration that the intestinal microbiota is important for promoting healthy maternal behavior and bonding between mom and offspring in an animal model.

 It is  difficult to study how individual strains of bacteria exert their influence on human behaviour, a connection often called the microbiota-gut-brain axis.

This study study provides an unprecedented understanding of how the intestinal microbiota can disrupt maternal behavior and how this can negatively impact development of an offspring.

Microbiota control of maternal behavior regulates early postnatal growth of offspring, Science Advances (2021). DOI: 10.1126/sciadv.abe6563 , advances.sciencemag.org/content/7/5/eabe6563

https://phys.org/news/2021-01-specific-bacteria-gut-prompt-mother.h...

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