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Comment by Dr. Krishna Kumari Challa on May 6, 2023 at 12:55pm

Mobile phone calls linked with increased risk of high blood pressure

Talking on a mobile for 30 minutes or more per week is linked with a 12% increased risk of high blood pressure compared with less than 30 minutes, according to research published recently in European Heart Journal—Digital Health.

It's the number of minutes people spend talking on a mobile that matter for heart health, with more minutes meaning greater risk.

Almost three-quarters of the global population aged 10 and over own a mobile phone. Nearly 1.3 billion adults aged 30 to 79 years worldwide have high blood pressure (hypertension). Hypertension is a major risk factor for heart attack and stroke and a leading cause of premature death globally.

Mobile phones emit low levels of radiofrequency energy, which has been linked with rises in blood pressure after short-term exposure. Results of previous studies on mobile phone use and blood pressure were inconsistent, potentially because they included calls, texts, gaming, and so on.

This study examined the relationship between making and receiving phone calls and new-onset hypertension. The study used data from the UK Biobank. A total of 212,046 adults aged 37 to 73 years without hypertension were included. Information on the use of a mobile phone to make and receive calls was collected through a self-reported touchscreen questionnaire at baseline, including years of use, hours per week, and using a hands-free device/speakerphone.

Participants who used a mobile phone at least once a week to make or receive calls were defined as mobile phone users.

The researchers analyzed the relationship between mobile phone usage and new-onset hypertension after adjusting for age, sex, body mass index, race, deprivation, family history of hypertension, education, smoking status, blood pressure, blood lipids, inflammation, blood glucose, kidney function and use of medications to lower cholesterol or blood glucose levels.

Part 1

Comment by Dr. Krishna Kumari Challa on May 6, 2023 at 12:51pm

Fruit fly gut research leads to discovery of new phosphate-storing organelle

Scientists  have discovered something remarkable while studying phosphate transport in fruit fly intestines—a never before seen organelle. Their results are published in the journal Nature, and a News and Views piece in the same journal discusses their findings.

Organelles are the structures performing specific functions within the cell and form the basis for most introductory biology courses. Major organelles include the nucleus, where DNA is kept and translated into RNA; the endoplasmic reticulum, where RNA is translated into proteins; and the Golgi apparatus, where enzymatic processing of proteins takes place; and the mitochondrion, which powers the cell and is involved in monitoring and regulating the cell as well as some intercellular communication.

A few dozen other minor organelles exist within animal cells, and it might have been assumed that every organelle had been discovered after so many years of research. But not so, as detailed in the researchers' new paper, "A phosphate-sensing organelle regulates phosphate and tissue homeostasis."

Immunostaining and ultrastructural analyses showed that PXo specifically appeared in a previously unknown multilamellar membrane—a newly discovered organelle the researchers named PXo bodies. The PXo was essentially storing phosphate in the PXo bodies. When PXo was downregulated or missing, the PXo bodies degraded, releasing the backup storage of phosphate into the cell.

Future investigations will be required to map this new organelle's full functions and interactions and could search for PXo bodies in other life forms.

 Chiwei Xu et al, A phosphate-sensing organelle regulates phosphate and tissue homeostasis, Nature (2023). DOI: 10.1038/s41586-023-06039-y

Emily Strachan et al, Phosphate-storing organelle discovered in fruit flies, Nature (2023). DOI: 10.1038/d41586-023-01410-5

Comment by Dr. Krishna Kumari Challa on May 6, 2023 at 12:29pm

When exposed to the prolonged microgravity of space, bad things happen to astronaut bodies. Physiological changes induce muscle atrophy, bone loss, and reduced aerobic and sensorimotor capacity, potentially affecting crewmember health and ability to perform mission tasks.

Exercise in space is called "countermeasure exercise" as it is designed to counter the physiological effects of being weightless. During these exercises (two 30-min aerobic exercises, six days a week), astronauts have higher rates of O₂ consumption, production of CO₂, metabolic heat production, and require more water to rehydrate.

While body size alone correlates to energy metrics (smaller stature, less energy used), missions requiring countermeasure exercise increase this disparity as larger bodies use more energy, need more oxygen, produce more CO₂ and create more heat. Additionally, the study found that females had 29% less water loss through sweating during a single bout of aerobic countermeasure exercise and so required less water to rehydrate.

The theoretical differences between female and male astronauts result from lower resting and exercising O₂ requirements of female astronauts, who are lighter than male astronauts at equivalent statures and have lower relative VO₂max (the rate at which the heart, lungs, and muscles can effectively use oxygen during exercise) values.

The study data, combined with the move towards smaller diameter habitat space for currently proposed mission modules, suggest that there may be several operational advantages to all-female crews during future human space exploration missions, with the most significant improvement coming from shorter females.

Jonathan P. R. Scott et al, Effects of body size and countermeasure exercise on estimates of life support resources during all-female crewed exploration missions, Scientific Reports (2023). DOI: 10.1038/s41598-023-31713-6

Part 2

Comment by Dr. Krishna Kumari Challa on May 6, 2023 at 12:28pm

Study finds female astronauts more efficient, suggesting future space missions with all-female crews

As humans contemplate life on other planets, we are immediately confronted with two choices. One is a journey to another solar system that would take tens of thousands of years (with current technology), requiring around 2,000 generations to live out their existence in the cramped confines of a spacecraft while adhering to a strict population control scheme. The other choice is Mars.

Mars has several advantages, not the least of which is proximity, eliminating the need to push people out of airlocks when the spacecraft is at capacity. It would also allow an advance team to set up basic infrastructure and to be the most efficient—the team should all be female.

Researchers from the Space Medicine Team, European Space Agency in Germany have conducted a study published in Scientific Reports that found female astronauts have lower water requirements for hydration, total energy expenditure, oxygen (O₂) consumption, carbon dioxide (CO₂) and metabolic heat production during space exploration missions compared to their male counterparts.

In the study, "Effects of body size and countermeasure exercise on estimates of life support resources during all-female crewed exploration missions," the team utilized an approach developed to estimate the effects of body "size" on life support requirements in male astronauts. For all parameters at all statures, estimates for females were lower than for comparable male astronauts.

When considering the limited space, energy, weight, and life support systems packed into a spacecraft on a long mission, the study finds that the female form is the most efficient body type for space exploration.

Compared to a previous study of theoretical male astronauts, the effect of body size on total energy expenditure was markedly less in females, with relative differences ranging from 5% to 29% lower. Compared at the 50th percentile stature for US females (1.6m), the reductions were even more significant at 11% to 41%. This translates into reduced use of oxygen, production of CO₂, metabolic heat, and water use.

Part 1

Comment by Dr. Krishna Kumari Challa on May 6, 2023 at 7:28am

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 11:32am

Technology enables conversion of mobile phone cameras into high-resolution microscopes

Researchers have developed the world's smallest LED (light-emitting diode) that enables the conversion of existing mobile phone cameras into high-resolution microscopes. Smaller than the wavelength of light, the new LED was used to build the world's smallest holographic microscope, paving the way for existing cameras in everyday devices such as mobile phones to be converted into microscopes via only modifications to the silicon chip and software. This technology also represents a significant step forward in the miniaturization of diagnostics for indoor farmers and sustainable agriculture.

This breakthrough was supplemented by the researchers' development of a revolutionary neural networking algorithm that is able to reconstruct objects measured by the holographic microscope, thus enabling enhanced examination of microscopic objects such as cells and bacteria without the need for bulky conventional microscopes or additional optics. The research also paves the way for a major advancement in photonics—the building of a powerful on-chip emitter that is smaller than a micrometer, which has long been a challenge in the field.

Zheng Li et al, A sub-wavelength Si LED integrated in a CMOS platform, Nature Communications (2023). DOI: 10.1038/s41467-023-36639-1

Iksung Kang et al, Simultaneous spectral recovery and CMOS micro-LED holography with an untrained deep neural network, Optica (2022). DOI: 10.1364/OPTICA.470712

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:27am

Deep sleep may mitigate Alzheimer's memory loss, research shows

As the most prevalent form of dementia, Alzheimer's disease destroys memory pathways and, in advanced forms, interferes with a person's ability to perform basic daily tasks. Roughly one in nine people over age 65 have the progressive disease—a proportion that is expected to grow rapidly as the baby boomer generation ages.

In recent years, scientists have probed the ways that deposits of beta-amyloid associate with Alzheimer's disease and how such deposits also affect memory more generally. In addition to sleep being a foundational part of memory retention, the team at UC Berkeley previously discovered that the declining amount of a person's deep sleep could act as a 'crystal ball' to forecast a faster rate of future beta-amyloid buildup in the brain, after which dementia is more likely set in.

A deep slumber might help buffer against memory loss for older adults facing a heightened burden of Alzheimer's disease, new research suggests.

Deep sleep, also known as non-REM slow-wave sleep, can act as a "cognitive reserve factor" that may increase resilience against a protein in the brain called beta-amyloid that is linked to memory loss caused by dementia. Disrupted sleep has previously been associated with faster accumulation of beta-amyloid protein in the brain. However, the new research  reveals that superior amounts of deep, slow-wave sleep can act as a protective factor against memory decline in those with existing high amounts of Alzheimer's disease pathology—a potentially significant advance that experts say could help alleviate some of dementia's most devastating outcomes.

Zsófia Zavecz et al, NREM sleep as a novel protective cognitive reserve factor in the face of Alzheimer's disease pathology, BMC Medicine (2023). DOI: 10.1186/s12916-023-02811-z

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:19am

Study finds doctors prescribing untested drug combinations with high addiction potential

The Center for Drug Safety and Effectiveness at Johns Hopkins University has led a study into prescription drug use of multiple concurrent central nervous system (CNS)-active drugs. They found widespread combination prescribing of drugs classified as Schedule II controlled substances with a high potential for psychological or physical dependence and with limited combined clinical trial testing.

The paper, "Medical use and combination drug therapy among US adult users of central nervous system stimulants: a cross-sectional analysis," published in BMJ Open, examined patterns of medical amphetamine and methylphenidate stimulant drug use, both substances considered to have a high potential for psychological or physical addiction.

Utilizing prescription drug claims for US adults aged 19 to 64 from a commercial insurance claims database with over 9.1 million continuously enrolled adults, stimulant use was defined as adults filling one or more stimulant prescriptions in a single year.

The study identified 276,223 individuals (3.0%) using Schedule II stimulants in 2020. They filled a median of eight prescriptions that provided 227 days of exposure. Among this group, 125,781 (45.5%) combined use of one or more additional CNS active drugs for a median of 213 days. Also, 66,996 (24.3%) stimulant users used two or more additional CNS-active medications for a median of 182  days. Among stimulants users, 131,485 (47.6%) used an antidepressant, 85,166 (30.8%) filled prescriptions for anxiety/sedative/hypnotic medications and 54,035 (19.6%) received opioid prescriptions.

Many adults using Schedule II stimulants simultaneously use one or more additional CNS-active drugs. As these can have tolerance and withdrawal effects or potential recreational abuse, the authors suggest that "discontinuation may be challenging," which is another way of stating that these individuals have likely formed a habitual dependence or addiction possibly requiring intervention or rehabilitation.

Once treatment has started, 75% of patients become long-term users. This underscores the possible risks of non-medical guideline use, noting the issues that warranted the classification of these drugs as having a high potential for psychological or physical dependence and their prominent appearance in toxicology drug rankings of fatal overdose cases.

 Thomas J Moore et al, Medical use and combination drug therapy among US adult users of central nervous system stimulants: a cross-sectional analysis, BMJ Open (2023). DOI: 10.1136/bmjopen-2022-069668

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:02am

Their genetic background—meaning the unique features in the B chromosome flies' genetic make-up—supports their preferential transmission to the next generation. That buys these  evolutionary time to become a new chromosome, whether that's picking up an essential gene or acquiring something that enables them to better cheat.

Importantly, meiotic drive is a powerful force that can shape how genomes evolve. 

Researchers are also examining how specific mutations can lead to chromosome breakage and new chromosome formation, revealing the mechanism of how supernumeraries arise and become requisite components of a genome.

Stacey L. Hanlon et al, B chromosomes reveal a female meiotic drive suppression system in Drosophila melanogaster, Current Biology (2023). DOI: 10.1016/j.cub.2023.04.028

Part 2

Comment by Dr. Krishna Kumari Challa on May 5, 2023 at 10:00am

Scientists discover the dynamics of an 'extra' chromosome in fruit flies

Most chromosomes have been around for millions of years. Now, researchers  have revealed the dynamics of a new, very young chromosome in fruit flies that is similar to chromosomes that arise in humans and is associated with treatment-resistant cancer and infertility. The findings may one day lead to developing more targeted therapies for treating these conditions.

A new study published in Current Biology on May 4, 2023, reveals how this small chromosome that arose less than 20 years ago has persisted in a single, lab-reared strain of the fruit fly, Drosophila melanogaster, and is correlated with supernumerary (extra) chromosomes in humans.

Supernumerary chromosomes in humans are found in cancer cells and frequently interfere with drugs designed to target tumors, making these types of cancers, like osteosarcoma, difficult to treat. In addition, the presence of supernumerary chromosomes in men can disrupt normal chromosome segregation during sperm production, which can cause infertility.

Being able to understand how supernumerary chromosomes arise and what their structures are can potentially illuminate their vulnerabilities. This may enable the development of potential therapeutic targets.

Called B chromosomes—as opposed to the standard "A" set of essential chromosomes—these genetic elements naturally appeared in a single laboratory stock of fruit flies.

Now, the researchers are witnessing chromosome birth and evolution in less than two decades.

How does something like this new chromosome apparently arise from nothing? More important, as these newly born B chromosomes do not possess any known essential genes for fruit fly function, how do they persist in a genome? In short, by cheating. They do not follow the rules.

Researchers discovered that the fruit fly B chromosomes are maintained by a mechanism called "meiotic drive" that enables the them to rebel against the usual rules of inheritance. The B chromosomes drive their way into the next generation during the formation of the egg to ensure their own persistence in more than half of the next generation.

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