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Comment by Dr. Krishna Kumari Challa on April 20, 2022 at 10:15am

Researchers obtain functional human blood cells via interspecies chimerism

Interspecies chimerism is a phenomenon of an organism consisting of tissue and genetic information from two different species. Currently, many studies investigate the use of interspecies chimerism with human pluripotent stem cells (hPSCs) to generate functional human cells, tissues or organs in large animals, which is expected to solve the shortage of functional tissues and organs for transplant. However, hPSCs interspecies chimerism faces barriers due to the extremely low chimeric contribution of hPSCs.

Recently, research teams led by Prof. Pan Guangjin and Prof. Lai Liangxue from the Guangzhou Institutes of Biomedicine and Health (GIBH) of the Chinese Academy of Sciences (CAS) made new progress on hPSCs interspecies chimerism. They developed an enhanced hPSCs in interspecies chimerism that allows the obtaining of functional human blood cells through interspecies chimerism technology for the first time. The study is published online in Stem Cell Reports.

The teams discovered that the rapid apoptosis  of hPSCs in the interspecies embryos was mainly due to the growth disadvantage and a "loser" state competing with the host animal stem cells. A new factor MYCN combined with anti-apoptotic gene BCL2 effectively overcame apoptosis of hPSCs and markedly promoted chimerism formation.

Strikingly, the teams isolated live human blood progenitor cells from blood-deficient mice through interspecies chimerism using hPSCs for complementation. The obtained cells can be further cultured and differentiated into different blood cells in dish.

This work presents an important method for understanding the interspecies chimerism barrier using hPSCs. The enhanced hPSCs for interspecies chimerism lays the foundation for acquiring human cells, tissues and organs for transplantation purposes in the future.

Yanling Zhu et al, Generating functional cells through enhanced interspecies chimerism with human pluripotent stem cells, Stem Cell Reports (2022). DOI: 10.1016/j.stemcr.2022.03.009

https://phys.org/news/2022-04-functional-human-blood-cells-interspe...

Comment by Dr. Krishna Kumari Challa on April 19, 2022 at 12:02pm

One step closer to creating new hair follicles

In a new study,  researchers take a unique approach to identify the molecular signals that induce a critical trigger for hair follicle formation and regeneration.

The findings could prove crucial for developing new therapies to re-grow hair—and provide a blueprint for unraveling other mysteries of tissue growth at the cellular level.

This is a decades-old problem that has been unsolvable because formation of the dermal condensate, the signaling center that induces the growth and differentiation of hair follicles, has been difficult to visualize and capture due to how rapidly they form.

Dermal condensates (DCs) are densely-packed clusters of cells, located under the skin's outer layer. DCs act as central commanders of hair follicle activity by sending signals to the skin's outer layer, instructing it to form hair follicles and determining follicle size.

Unraveling the steps that induce DC formation has been a major challenge for researchers, because the process is difficult to track over time and tease apart experimentally. Overcoming this barrier could open the door to effective methods for reproducing DCs to test new drugs for hair loss and to generate hair follicles in 3D culture models.

For this study researchers  took a unique approach to study DCs.

Using single-cell RNA-sequencing data from mouse skin, they designed a computational approach to align a series of single-cell profile "snapshots" to reconstruct the time course of DC development. This provided a roadmap that delineates how an immature dermal cell drives itself to maturity. More importantly, the approach allowed the researchers to investigate the molecular signals that serve as engines in the process. By combining their computational findings with in vivo genetic experiments, they were able to pin down the critical signals involved in DC formation.

One of the signals is known as Wnt and the other is called "sonic hedgehog," or SHH. Both signals are considered essential in the development of many tissue types and play a role in regulating adult tissue homeostasis and regeneration. They are also implicated in pathological states such as cancer when they are aberrantly overactivated.

For the study, the researchers were able to genetically modulate these signals to curtail the speed of DC formation, effectively playing out the DC formation process in slow motion.

This work will help pave the way to developing robust methods for recreating DCs in the laboratory, and for adult hair follicle regeneration.

https://medicine.yale.edu/news-article/one-step-closer-to-creating-...

Comment by Dr. Krishna Kumari Challa on April 19, 2022 at 11:26am

Comment by Dr. Krishna Kumari Challa on April 17, 2022 at 10:09am

Researchers gathered a sample of microbes they knew to be dominated by this methane-slurping archaea, and grew them in an oxygen-lacking environment where methane was the only electron donor.

Near this colony they also placed a metal anode set at zero voltage, effectively creating an electrochemical cell primed to generate a current.

They created a kind of battery with two terminals, where one of these is a biological terminal and the other one is a chemical terminal. 

Researchers grew the bacteria on one of the electrodes, to which the bacteria donate electrons resulting from the conversion of methane. 

After analyzing the conversion of methane to carbon dioxide and measuring fluctuating currents that spiked as high as 274 milliamps per square centimeter, the team deduced a little over a third of the current could be attributed directly to the breaking down of methane.

As far as efficiency goes, 31 percent of the energy in the methane had transformed into electrical power, making it somewhat comparable with some power stations.

Tinkering more with the process could see to the creation of highly efficient living batteries that run on biogas, wringing more spark from every bit of gas and reducing the need for piping methane over long distances. 

https://www.frontiersin.org/articles/10.3389/fmicb.2022.820989/full

https://www.sciencealert.com/these-microbes-breathe-in-methane-and-...

Part 2

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Comment by Dr. Krishna Kumari Challa on April 17, 2022 at 10:06am

Some Microbes Breathe Methane And Turn It Into Electricity in a Weird Living Battery

As far as greenhouse gases go, methane is the quiet villain that could stealthily drag us ever deeper into the climate crisis. In our atmosphere, it is at least 25 times more effective at trapping heat than carbon dioxide.

It's also not that efficient – through burning, less than half of the energy in the natural gas can be converted into electrical power.

In an effort to squeeze more electrons from every puff of methane, researchers in the Netherlands have explored a rather unconventional form of power station – one you'd need a microscope to see.

"In the current biogas installations, methane is produced by microorganisms and subsequently burnt, which drives a turbine, thus generating power. Less than half of the biogas is converted into power, and this is the maximum achievable capacity. But can we  do better using microorganisms?

Scientists found a type of archaea – bacteria-like microbes known for their extraordinary talents of surviving under strange and harsh conditions, including being able to break down methane in environments deprived of oxygen.

This specific type, known as anaerobic methanotrophic (ANME) archaea, manage this metabolic trick by offloading electrons in a chain of electrochemical reactions, employing some kind of metal or metalloid outside of their cells or even donating them to other species in their environment.

First described in 2006, the ANME genus Methanoperedens was found to oxidize methane with a little help from nitrates, making them right at home in the wet bogs of the Netherland's fertilizer-soaked agricultural culverts.

Attempts to pull electrons from this process in microbial fuel cells have resulted in tiny voltages being produced, without any clear confirmation on exactly which processes might be behind the conversion.

If these archaea are to ever show promise as methane-gobbling power cells, they'd really need to churn out a current in a clear, unambiguous fashion.

Part 1

Comment by Dr. Krishna Kumari Challa on April 16, 2022 at 11:38am

International collaboration reveals how the human brain evolved to harness abstract thought

 The human brain is organized in functional networks—connected brain regions that communicate with each other through dedicated pathways. That is how we perceive our senses, how the body moves, how we are able to remember the past and plan for the future. The "default mode" network is the part of our connected brain that is responsible for abstract and self-directed thought. When we process external sensory information, the default mode network turns off, and when there is less going on outside our bodies it turns on. Whether the same default mode network is found in mammals similar to humans has not been firmly answered; different studies have yielded different conclusions.

In an international collaboration across seven laboratories, in five institutions, across three countries , researchers compared data from humans and non-hominoid primates (macaques, marmosets and mouse lemurs) to more definitively answer this question.
Surprisingly, these results showed that in all species other than humans, the brain areas that comprise the default mode network involve two systems not strongly connected with each other.

These regions, one responsible for suppression of external events and one for more cognitive tasks, appear to be linked only recently in evolution. It is this linkage that may have facilitated the capacity for abstract thought that led to the rapid evolution of human cognitive abilities.

The unexpected finding changes the way we think about brain networks. Atypical patterns of connectivity between brain areas are signatures of neurodevelopmental disorders and mental illnesses. These conditions are a significant health and societal issue that affects individuals' ability to healthily function in society. Understanding how unusual patterns of brain connectivity emerge could lead to better diagnosis and treatment of these conditions.

The article, "An evolutionary gap in primate default mode network organization" was published in the journal Cell Reports on April 12.

https://engineering.vanderbilt.edu/news/2022/international-collabor...

https://researchnews.cc/news/12686/International-collaboration-reve...

Comment by Dr. Krishna Kumari Challa on April 16, 2022 at 9:52am

Latest recommendations on how waist-to-height ratio can impact your health

New health guidance on the need to keep your waist size to half your height to ensure healthy living was recommended by Bayes Business School eight years ago.

In 2014, research from Bayes Business School showed that the waist-to-height ratio (WHtR) is a better predictor of mortality risk than the commonly used BMI.

Today, draft guidance from the National Institute for Health and Care Excellence (NICE) has stated that an adult's waist should be less than half their height to reduce health risks, including type 2 diabetes and heart disease.

The guidance, published ahead of the release of a full report in September, also says that while measuring body mass index (BMI) is useful it doesn't consider excess weight around the abdomen—scientifically termed "central adiposity."

These new recommendations come after researchers at Bayes Business School and Ashwell Associates called for the measurement—waist circumference divided by height—to replace BMI in primary public health screening.

The study found that as many as 20 years of life for men can be lost by failing to sustain your waistline. The figure is approximately 10 years for women.

Margaret Ashwell et al, Waist-to-Height Ratio Is More Predictive of Years of Life Lost than Body Mass Index, PLoS ONE (2014). DOI: 10.1371/journal.pone.0103483

https://medicalxpress.com/news/2022-04-latest-waist-to-height-ratio...

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Comment by Dr. Krishna Kumari Challa on April 16, 2022 at 9:31am

Injectable stem cell assembly for cartilage regeneration

A new study  has established an injectable hybrid inorganic (IHI) nanoscaffold-templated stem cell assembly and applied it to the regeneration of critically-sized cartilage defects.

Cartilage injuries are often devastating and most of them have no cures due to the intrinsically low regeneration capacity of cartilage tissues. The rise of 3D stem cell culture systems has led to breakthroughs in developmental biology, disease modeling, and regenerative medicine. For example, stem cells, once transplanted successfully, could initially secret trophic factors for reducing inflammation at sites of cartilage injuries and then differentiate into cartilage cells (e.g., chondrocytes) for functional restoration. Nevertheless, there are critical barriers remaining to be overcome before the therapeutic potential of stem cell therapies can be realized. The limited control over the chondrogenic differentiation of stem cells in vivo has often resulted in compromised regenerative outcomes. Moreover, due to the prevalence of oxidative stress and inflammation in the microenvironment of injury sites, stem cells frequently undergo apoptosis after injection. To address these challenges, the researchers demonstrated the development of a 3D IHI nanoscaffold-templated stem cell assembly system for advanced 3D stem cell culture and implantation. 3D-IHI nanoscaffold rapidly assembles stem cells into injectable tissue constructs through tailored 3D cell-cell and cell-matrix interactions, deeply and homogeneously delivers chondrogenic proteins in the assembled 3D culture systems, and controllably induces chondrogenesis through nanotopographical effects.

Once implanted in vivo in a rabbit cartilage injury model, 3D-IHI nanoscaffold effectively modulates dynamic microenvironment after cartilage injury through the integration of the aforementioned regenerative cues, and simultaneously scavenges reactive oxygen species using a manganese dioxide-based composition. In this way, accelerated repair of cartilage defects with rapid tissue reconstruction and functional recovery is realized both in the short term and long term. Given the excellent versatility and therapeutic outcome of 3D-IHI nanoscaffold-based cartilage regeneration, it may provide promising means to advance a variety of tissue engineering applications.

Shenqiang Wang et al, Injectable hybrid inorganic nanoscaffold as rapid stem cell assembly template for cartilage repair, National Science Review (2022). DOI: 10.1093/nsr/nwac037

https://phys.org/news/2022-04-stem-cell-cartilage-regeneration.html...

Comment by Dr. Krishna Kumari Challa on April 16, 2022 at 9:08am

Gut bacterium supports growth in infants with severe acute malnutrition

About 18 million children under age five suffer from severe acute malnutrition, and more than 3 million children die from it each year. Treatment with high-calorie supplemental foods and antibiotics can prevent deaths, but these interventions often have limited impact on the long-term effects of severe acute malnutrition, such as persistent stunted growth, disrupted immune function and impaired brain development. Even when treated with standard therapeutic foods, many children continue to have moderate forms of the disease and are at risk of falling back into severe acute malnutrition.

A new study, published April 13 in the journal Science Translational Medicine, from Washington University School of Medicine in St. Louis and the International Center for Diarrheal Disease Research in Dhaka, Bangladesh (icddr,b), shows that a standard milk-based therapy plus treatment with a specific strain of gut bacteria known as Bifidobacterium infantis (B. infantis) for four weeks promotes weight gain in infants with severe acute malnutrition, with accompanying reductions in gut inflammation. 

The B. infantis strain was chosen for the trial because it has been shown to be safe to give to infants as a probiotic and is known to thrive on specific carbohydrates present in human breast milk. Importantly, the investigators found that B. infantis was either undetectable or present in markedly reduced amounts in infants with severe acute malnutrition compared to those with healthy growth.

 Michael J. Barratt et al, Bifidobacterium infantis treatment promotes weight gain in Bangladeshi infants with severe acute malnutrition, Science Translational Medicine (2022). DOI: 10.1126/scitranslmed.abk1107

https://medicalxpress.com/news/2022-04-gut-bacterium-growth-infants...

Comment by Dr. Krishna Kumari Challa on April 15, 2022 at 12:47pm

The time-of-flight neutron spectrometer Pelican at ANSTO's Center for Neutron Scattering has been used to measure the vibrational densities of states for several liquid systems including water, liquid metal, and polymer liquids. The Pelican instrument has the extreme sensitivity to measure rotational and translational vibrations over short time intervals and at low energies.

The experiments at ANSTO confirmed the linear relationship of the vibrational density of states with frequency at low energies as predicted earlier.

Caleb Stamper et al, Experimental Confirmation of the Universal Law for the Vibrational Density of States of Liquids, The Journal of Physical Chemistry Letters (2022). DOI: 10.1021/acs.jpclett.2c00297

Alessio Zaccone et al, Universal law for the vibrational density of states of liquids, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2022303118

https://phys.org/news/2022-04-surfing-atomic-scale-scientists-exper...

Part 2

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