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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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Comment by Dr. Krishna Kumari Challa on July 19, 2022 at 7:07am

SPACE TRASH! ft. Chemistry

Comment by Dr. Krishna Kumari Challa on July 19, 2022 at 6:37am

How blood vessels remember a stroke

The vascular system within our body provides a constant flow of nutrients, hormones and other resources, thus ensuring efficient transport. Researchers now  investigated in which way such a network is able to adapt and change over time. Using computer simulations, they modeled the network and identified adaptation rules for its connections.

They found that the strength of a connection within a network depends on the local flow. This means that links with a low flow below a certain threshold will decay more and more until they eventually vanish.

 As the amount of biological material to build the vascular system is limited and should be used in an efficient way, this mechanism offers an elegant way to streamline the vascular system.

Changes in the network are persistent

Once a connection has become very weak due to a low flow rate, it is very difficult to recover that connection. A common example for this is the blockage of a blood vessel, which in a bad case even might lead to a stroke. During a stroke, some blood vessels in a certain brain region become very weak due of the blockage of blood flow.

The researchers found that in such a case, adaptations in the network are permanent and are maintained after the obstacle is removed. One can say that the network prefers to reroute the flow through existing stronger connections instead of re-growing weaker connections—even if the flow would require the opposite.

With this new understanding of network memory, the researchers can now explain that blood flow permanently changes even after successful removal of the clot. 

Komal Bhattacharyya et al, Memory Formation in Adaptive Networks, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.129.028101

Comment by Dr. Krishna Kumari Challa on July 19, 2022 at 6:30am

A tear-soluble contact lens with silicon nanoneedles to treat eye diseases

a team of researchers  has developed a type of contact lens with embedded nanoneedles for treating eye diseases. In their paper published in the journal Science Advances, the group describes how they made their contact lens and how well it worked when tested on rabbits.

Current methods of delivering medications to the eye involve therapies that are applied directly to the outer eye or are injected into it. Neither method is optimal—applied medicines do not penetrate deep enough into the eye and injected medicines are painful and often lead to inflammation. In this new effort, the researchers have come up with a new approach—application of a nanoneedle infused contact lens.

The researchers began with the notion of imbedding nanoneedles into the eye that degrade over time, releasing medication—and the nanoneedles would be so small that they would not cause pain or discomfort. To get the nanoneedles into the eye, they would attach them to a contact lens that would dissolve soon after application to the eye.

The researchers began with the nanoneedles—they grew them using a silicon base, which ensured they would take a long time to dissolve in the eye. They also made them very small—10 times smaller than any that had been tried before. They also developed a unique way to make them, it involved growing the nanoneedles from a silicon and medication mix, then applying a polymer layer to crack them where they joined the silicon base. This involved coating the tiny needles with polymethyl methacrylate. Then the polymer was peeled off the wafer base. The researchers next coated the base of the nanoneedles with another polymer and then removed the first layer. That left the needles embedded in the second polymer material. Once the design was confirmed, the researchers repeated the process in a way that resulted in the base being formed into a contact-lens shape. The final step involved adding a second medication to the lens—one that would be applied to the eye all-at-once as the base dissolved.

The researchers tested their product on rabbit-models and found an almost complete reduction in corneal neovascularization after just 28 days. The group notes that much more work will need to be done before their nanoneedle-based therapy could be used to treat human patients. It will first have to be tested both for efficacy and safety, and also a means for storing the lens once created will need to be developed.

Woohyun Park et al, Biodegradable silicon nanoneedles for ocular drug delivery, Science Advances (2022). DOI: 10.1126/sciadv.abn1772

Comment by Dr. Krishna Kumari Challa on July 18, 2022 at 11:38am

Study: Sentences have their own connection in the brain

A new study finds that incoming speech sounds are connected by our brain to our knowledge of grammar, which is quite abstract in nature. But the big question is how does the brain process complex grammatical structures?

A group of researchers from the Max Planck Institute of Psycholinguistics and Radboud University in Nijmegen discovered that the brain encodes the structure of sentences (‘the vase is red’) and phrases (‘the red vase’) into various neural firing patterns.

The findings of the neuroimaging study were published in the PLOS Biology.

How does the brain represent sentences? This is one of the fundamental questions in neuroscience, because sentences are an example of abstract structural knowledge that is not directly observable from speech. While all sentences are made up of smaller building blocks, such as words and phrases, not all combinations of words or phrases lead to sentences.

In fact, listeners need more than just knowledge of which words occur together: they need abstract knowledge of language structure to understand a sentence. So how does the brain encode the structural relationships that make up a sentence?

The researchers created sets of spoken Dutch phrases (such as de rode vaas ‘the red vase’) and sentences (such as de vaas is rood ‘the vase is red’), which were identical in duration and number of syllables, and highly similar in meaning. They also created pictures with objects (such as a vase) in five different colours. Fifteen adult native speakers of Dutch participated in the experiment.

For each spoken stimulus, they were asked to perform one of three tasks in random order. The first task was structure-related, as participants had to decide whether they had heard a phrase or a sentence by pushing a button. The second and third task were meaning-related, as participants had to decide whether the colour or object of the spoken stimulus matched the picture that followed.

As expected from computational simulations, the activation patterns of neurons in the brain were different for phrases and sentences, in terms of both timing and strength of neural connections. These findings show how the brain separates speech into linguistic structure by using the timing and connectivity of neural firing patterns. These signals from the brain provide a novel basis for future research on how our brains create language.

https://theprint.in/science/study-sentences-have-their-own-connecti...

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Comment by Dr. Krishna Kumari Challa on July 18, 2022 at 9:56am

What is the difference between reproducibility and replicability?

 “Reproducibility” refers to instances in which the original researcher's data and computer codes are used to regenerate the results, while “replicability” refers to instances in which a researcher collects new data to arrive at the same scientific findings as a previous study.

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