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Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:54am

Nanomembrane system could help diagnose diseases by isolating biomarkers in tears

Going to the doctor might make you want to cry, and according to a new study, doctors could someday put those tears to good use. In ACS Nano, researchers report a nanomembrane system that harvests and purifies tiny blobs called exosomes from tears, allowing researchers to quickly analyze them for disease biomarkers. Dubbed iTEARS, the platform could enable more efficient and less invasive molecular diagnoses for many diseases and conditions, without relying solely on symptoms.

Diagnosing diseases often hinges on assessing a patient's symptoms, which can be unobservable at early stages, or unreliably reported. Identifying molecular clues in samples from patients, such as specific proteins or genes from vesicular structures called exosomes, could improve the accuracy of diagnoses. However, current methods for isolating exosomes from these samples require long, complicated processing steps or large sample volumes. Tears are well-suited for sample collection because the fluid can be collected quickly and non-invasively, though only tiny amounts can be harvested at a time. So,  researchers wondered if a nanomembrane system, which they originally developed for isolating exosomes from urine and plasma, could allow them to quickly obtain these vesicles from tears and then analyze them for disease biomarkers.

The researchers successfully distinguished between healthy controls and patients with various types of dry eye disease based on a proteomic assessment of extracted proteins. Similarly, iTEARS enabled researchers to observe differences in microRNAs between patients with diabetic retinopathy and those that didn't have the eye condition, suggesting that the system could help track disease progression. The team says that this work could lead to a more sensitive, faster and less invasive molecular diagnosis of various diseases—using only tears.

Liang Hu et al, Discovering the Secret of Diseases by Incorporated Tear Exosomes Analysis via Rapid-Isolation System: iTEARS, ACS Nano (2022). DOI: 10.1021/acsnano.2c02531

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:50am

Mouse study shows dopamine released in brain in response to hydration

A team of researchers  has found that a certain part of the brain releases dopamine in response to hydration. In their paper published in the journal Nature, the group describes experiments they conducted with thirsty mice.

Prior research has shown that certain parts of the brain release dopamine, a chemical compound, as a means of providing pleasurable feedback to other parts of the brain. It is released during sex, for example, or when a person eats something they like, particularly foods that are sweet or fatty. In this new effort, the researchers have found that another part of the brain releases dopamine—this time when the brain is hydrated.

Noting that many animals have learned to determine which foods contain more water, the researchers wondered if there was a feedback mechanism in the brain prompting them to eat those foods that would provide more water, leading to more hydration in their brains. To find out, they turned to mice.

The experiments involved restricting water in test mice and using technology that allowed them to focus on the ventral tegmental area (VTA) in the brain. In one experiment, thirsty mice were given unlimited access to water for five minutes while the researchers monitored brain waves emanating from the VTA—a means of measuring how much, if any, dopamine was being produced. As expected, dopamine production levels rose as soon as the mice began drinking. But the researchers were then surprised to find that 10 minutes later, the dopamine levels rose again—coinciding with the amount of time it took for the water they had been drinking to reach their brain. The researchers then repeated the experiment but added salt to the water—the second bump in dopamine was much smaller due to the dehydrating impact of the salt.

James C. R. Grove et al, Dopamine subsystems that track internal states, Nature (2022). DOI: 10.1038/s41586-022-04954-0

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:22am

With just a tablespoon of blood, researchers aim to transform cancer treatment

Researchers  have developed a new blood test that provides unprecedented insight into a patient's cancer make-up, potentially allowing doctors to better select treatment options that will improve patient outcomes.

The technology was outlined in a study published recently in Nature.

The first-of-its-kind blood test analyzes the DNA that metastatic cancers shed into the bloodstream, known as circulating tumor DNA or ctDNA. By sequencing the entire genome of this ctDNA, the test reveals characteristics that are unique to each patient's cancer, giving physicians new tools to develop more personalized treatment plans.

With only a few drops of blood, we can now uncover critical information about a person's overall disease and how best to manage their cancer. This test has the potential to help clinicians choose better tailored treatment options and to more efficiently detect treatment resistance, allowing clinicians to adjust clinical care as needed.

 Alexander Wyatt, Deep whole-genome ctDNA chronology of treatment-resistant prostate cancer, Nature (2022). DOI: 10.1038/s41586-022-04975-9. www.nature.com/articles/s41586-022-04975-9

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:14am

Human eggs remain healthy for decades by putting 'batteries on standby mode'

Immature human egg cells skip a fundamental metabolic reaction thought to be essential for generating energy, according to the findings of a study by researchers at the Center for Genomic Regulation (CRG) published recently in the journal Nature.

By altering their metabolic activity, the cells avoid creating reactive oxygen species, harmful molecules that can accumulate, damage DNA and cause cell death. The findings explain how human egg cells remain dormant in ovaries for up to 50 years without losing their reproductive capacity.

Humans are born with all the supply of egg cells they have in life. As humans are also the longest-lived terrestrial mammal, egg cells have to maintain pristine conditions while avoiding decades of wear-and-tear. This new work shows this problem is solved by skipping a fundamental metabolic reaction that is also the main source of damage for the cell. As a long-term maintenance strategy, its like putting batteries on standby mode. This represents a brand new paradigm never before seen in animal cells.

Human eggs are first formed in the ovaries during fetal development, undergoing different stages of maturation. During the early stages of this process, immature egg cells known as oocytes are put into cellular arrest, remaining dormant for up to 50 years in the ovaries. Like all other eukaryotic cells, oocytes have mitochondria—the batteries of the cell—which they use to generate energy for their needs during this period of dormancy.

Using a combination of live imaging, proteomic and biochemistry techniques, the authors of the study found that mitochondria in both human and Xenopus oocytes use alternative metabolic pathways to generate energy never before seen in other animal cell types.

A complex protein and enzyme known as complex I is the usual "gatekeeper" that initiates the reactions required to generate energy in mitochondria. This protein is fundamental, working in the cells that constitute living organisms ranging from yeast to blue whales. However, the researchers found that complex I is virtually absent in oocytes. 

The findings could also lead to new strategies that help preserve the ovarian reserves of patients undergoing cancer treatment.

 Elvan Böke, Oocytes maintain ROS-free mitochondrial metabolism by suppressing complex I, Nature (2022). DOI: 10.1038/s41586-022-04979-5. www.nature.com/articles/s41586-022-04979-5

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 6:57am

Strange new phase of matter created in quantum computer acts like it has two time dimensions

By shining a laser pulse sequence inspired by the Fibonacci numbers at atoms inside a quantum computer, physicists have created a remarkable, never-before-seen phase of matter. The phase has the benefits of two time dimensions despite there still being only one singular flow of time, the physicists report July 20 in Nature.

This mind-bending property offers a sought-after benefit: Information stored in the phase is far more protected against errors than with alternative setups currently used in quantum computers. As a result, the information can exist without getting garbled for much longer, an important milestone for making quantum computing viable.

The approach's use of an "extra" time dimension "is a completely different way of thinking about phases of matter.

The workhorses of the team's quantum computer are 10 atomic ions of an element called ytterbium. Each ion is individually held and controlled by electric fields produced by an ion trap, and can be manipulated or measured using laser pulses.

Each of those atomic ions serves as what scientists dub a quantum bit, or "qubit." Whereas traditional computers quantify information in bits (each representing a 0 or a 1), the qubits used by quantum computers leverage the strangeness of quantum mechanics to store even more information. Just as Schrödinger's cat is both dead and alive in its box, a qubit can be a 0, a 1 or a mashup—or "superposition"—of both. That extra information density and the way qubits interact with one another promise to allow quantum computers to tackle computational problems far beyond the reach of conventional computers.

Though the findings demonstrate that the new phase of matter can act as long-term quantum information storage, the researchers still need to functionally integrate the phase with the computational side of quantum computing. 

Philipp Dumitrescu, Dynamical topological phase realized in a trapped-ion quantum simulator, Nature (2022). DOI: 10.1038/s41586-022-04853-4. www.nature.com/articles/s41586-022-04853-4

Comment by Dr. Krishna Kumari Challa on July 20, 2022 at 8:06am

Malarial Host-Parasite Clash Causes Deadly Blood Sugar Drop

Scientists say they have finally figured out why some people with severe malaria end up with dangerous hypoglycemia, also reporting that the condition starves the parasite into changing tactics from virulence to transmission.

Malaria is one of the world's deadliest diseases, responsible for 627,000 deaths worldwide in 2020 alone. In severe cases, patients develop dangerously low blood sugar levels. This complication is especially perilous in children and can be fatal if left untreated, but why it develops in the first place has been a long-standing mystery.

Now, in a study published recently (July 15) in Cell Metabolism, researchers describe the complicated tug-of-war between host and parasite that appears to explain malaria-associated hypoglycemia. According to the study, the host’s blood sugar drops to dangerously low levels as the malaria parasite destroys blood cells. This starves the parasite, which responds by becoming less likely to kill the already-fragile host—but more likely to spread to others.

The researchers explain that both the host and the parasite are demonstrating adaptive behaviors during this process. The host is ridding itself of the parasite by lowering its blood sugar, they say, and the parasite is becoming less virulent to try and keep both itself and the host alive long enough to seed the next generation.  

https://www.cell.com/cell-metabolism/fulltext/S1550-4131(22)00231-5

Comment by Dr. Krishna Kumari Challa on July 20, 2022 at 7:58am

Gas Entrapping Materials to control inflammation

Comment by Dr. Krishna Kumari Challa on July 20, 2022 at 7:42am

Scientists develop new method and device to isolate single cells using electric fields

In cancer research, it all comes down to a single cell. Over the last decade, cancer researchers have homed in on the fact that an individual cell from a tumor can be used to perform molecular analyses that reveal important clues about how the cancer developed, how it spreads and how it may be targeted. With this in mind, a team of researchers  has developed an advanced way to isolate single cells from complex tissues. In a study published in Scientific Reports, they show how the approach not only results in high-quality, intact single cells, but is also superior to standard isolation methods in terms of labor, cost and efficiency. The challenge was to develop a technology to enable researchers to more quickly and easily isolate cells from biopsied cancer tissue to ready it for analysis.

In the new process, a tissue biopsy is placed in a liquid-filled receptacle between two parallel plate electrodes. Instead of enzymes, electric field fluctuations are applied to create opposing forces within the liquid. These forces cause the tissue cells to move in one direction and then in the opposite direction, which leads them to cleanly separate, or disassociate from one another.

The new process resulted in dissociation of biopsy tissue in as little as 5 minutes -- three times faster than leading enzymatic and mechanical techniques described  in a previous study. The approach also resulted in "good dissociation of tissues into single cells while preserving cell viability, morphology and cell cycle progression, suggesting utility for sample preparation of tissue specimens for direct single-cell analysis.

According to the researchers, the new approach is, at minimum, 300% more effective than even the most optimized techniques using simultaneous chemical and mechanical dissociation.

E. Celeste Welch, Harry Yu, Gilda Barabino, Nikos Tapinos, Anubhav Tripathi. Electric-field facilitated rapid and efficient dissociation of tissues Into viable single cells. Scientific Reports, 2022; 12 (1) DOI: 10.1038/s41598-022-13068-6

Comment by Dr. Krishna Kumari Challa on July 19, 2022 at 9:02am

Scientifically proven tips on how to keep cool in the heat

If you're unable to take up residence inside air-conditioned buildings here are a few tips, backed by science, that can help you to stay cool.

1) Shed a few layers

Our bodies have cooling all sussed out. When we get hot, we sweat, and as that sweat evaporates it draws heat energy from the skin, cooling us down in the process. So the best way to stay cool if you're out of direct sunlight (and in sympathetic company) is to wear as little as possible.

If you do need to cover up, however, wear loose-fitting clothes that allow air to flow over the skin, speeding up evaporation. Also try to wear light-coloured garments, as these absorb less of the Sun's radiation than darker clothing.

If you're exercising, meanwhile, don some high-tech sportswear that uses 'moisture-wicking' fabrics. These fabrics transport sweat away from the skin to the outer layers of the material, where it can spread out and evaporate away.

2) Have a drink...

As you sweat, you'll need to replace all that water you're losing. One way to figure out how hydrated you are is to check the colour of your urine. If it's light like lemonade, then you're probably fine; if it's dark like apple juice then you're dehydrated.

When you become dehydrated, the body slows down its sweat rate to conserve fluid, making you even hotter. So a drink can rehydrate you and help you cool down.

But while an ice-cold cider may seem like a good idea, alcohol is actually a diuretic (it causes you to pee more), which can make you dehydrated. It also causes the blood vessels in your skin to dilate, making you feel hotter. So if you want to stay cool, go easy on the booze.

3) Don't open all the windows

To create a refreshing breeze on a stifling summer's day, don't haphazardly throw open the windows. Instead, generate a draught by opening downstairs windows that are in the shade, and upstairs windows that are in the Sun.

Because hot air rises, sunny upstairs rooms will be warmer than those that are downstairs in the shade. This sets up a pressure difference, and by strategically opening windows in these rooms you'll create a breeze that draws in cool, fresh air from downstairs and forces warm air out of the house. You can increase this effect by using window-mounted fans to suck in air downstairs and blow out air upstairs.

Comment by Dr. Krishna Kumari Challa on July 19, 2022 at 8:57am

Chemists Just Rearranged Atomic Bonds in a Single Molecule For The First Time

Chemical engineering has taken a step forward, with researchers from the University of Santiago de Compostela in Spain, the University of Regensburg in Germany, and IBM Research Europe forcing a single molecule to undergo a series of transformations with a tiny nudge of voltage.

Ordinarily, chemists gain precision over reactions by tweaking parameters such as the pH, adding or removing available proton donors to manage the way molecules might share or swap electrons to form their bonds.

"By these means, however, the reaction conditions are altered to such a degree that the basic mechanisms governing selectivity often remain elusive," the researchers note in their report, published in the journal Science.

In other words, the complexity of forces at work pushing and pulling across a large organic molecule can make it hard to get a precise measure on what's occurring at each and every bond.

The team started with a substance called 5,6,11,12-tetrachlorotetracene (with the formula C18H8Cl4) – a carbon-based molecule that looks like a row of four honeycomb cells flanked by four chlorine atoms hovering around like hungry bees.

Sticking a thin layer of the material to a cold, salt-crusted piece of copper, the researchers drove the chlorine-bees away, leaving a handful of excitable carbon atoms holding onto unpaired electrons in a range of related structures.

Two of those electrons in some of the structures happily reconnected with each other, reconfiguring the molecule's general honeycomb shape. The second pair were also keen to pair up not just with each other, but with any other available electron that might buzz their way.

Ordinarily, this wobbly structure would be short-lived as the remaining electrons married up with each other as well. But the researchers found this particular system wasn't an ordinary one.

With a gentle push of voltage from an atom-sized cattle prod, they showed they could force a single molecule to connect that second pair of electrons in such a fashion that the four cells were pulled out of alignment in what's known as a bent alkyne.

Shaken a little less vigorously, those electrons paired up differently, distorting the structure in a completely different fashion into what's known as a cyclobutadiene ring.

Each product was then reformed back into the original state with a pulse of electrons, ready to flip again at a moment's prompting.

By forcing a single molecule to contort into different shapes, or isomers, using precise voltages and currents, the researchers could gain insight into the behaviors of its electrons and the stability and preferable configurations of organic compounds.

From there it could be possible to whittle down the search for catalysts that could push a large-scale reaction of countless molecules in one direction, making the reaction more specific.

https://www.science.org/doi/10.1126/science.abo6471

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