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Archive for the ‘chemistry’ category: Page 310

Aug 21, 2019

Rapid tissue regeneration induced by intracellular ATP delivery—A preliminary mechanistic study

Posted by in categories: biotech/medical, chemistry

Circa 2017


We have reported a new phenomenon in acute wound healing following the use of intracellular ATP delivery—extremely rapid tissue regeneration, which starts less than 24 h after surgery, and is accompanied by massive macrophage trafficking, in situ proliferation, and direct collagen production. This unusual process bypasses the formation of the traditional provisional extracellular matrix and significantly shortens the wound healing process. Although macrophages/monocytes are known to play a critical role in the initiation and progression of wound healing, their in situ proliferation and direct collagen production in wound healing have never been reported previously. We have explored these two very specific pathways during wound healing, while excluding confounding factors in the in vivo environment by analyzing wound samples and performing in vitro studies. The use of immunohistochemical studies enabled the detection of in situ macrophage proliferation in ATP-vesicle treated wounds. Primary human macrophages and Raw 264.7 cells were used for an in vitro study involving treatment with ATP vesicles, free Mg-ATP alone, lipid vesicles alone, Regranex, or culture medium. Collagen type 1α 1, MCP-1, IL-6, and IL-10 levels were determined by ELISA of the culture supernatant. The intracellular collagen type 1α1 localization was determined with immunocytochemistry. ATP-vesicle treated wounds showed high immunoreactivity towards BrdU and PCNA antigens, indicating in situ proliferation. Most of the cultured macrophages treated with ATP-vesicles maintained their classic phenotype and expressed high levels of collagen type 1α1 for a longer duration than was observed with cells treated with Regranex. These studies provide the first clear evidence of in situ macrophage proliferation and direct collagen production during wound healing. These findings provide part of the explanation for the extremely rapid tissue regeneration, and this treatment may hold promise for acute and chronic wound care.

Wound healing is a complex and dynamic process involving the replacement of devitalized and missing structures. The traditional view of wound healing is that it involves hemostasis, inflammation, proliferation, and remodeling, and these steps result in a lag of 3–6 d before reepithelialization starts [1,2]. We have discovered that the intracellular delivery of adenosine triphosphate using ATP-vesicles as an acute wound treatment enhances wound healing [3,4]. The most unprecedented finding was that new tissue started to generate within 24 h, and it continued to grow to eliminate the wound cavity quickly [4–6]. This growth was attained by early and massive monocyte/macrophage trafficking, proliferation, and fast collagen production for direct formation of extracellular matrix (ECM).

Aug 21, 2019

Scientists find a way to create long-life, fast-charging batteries

Posted by in categories: chemistry, energy, physics, transportation

A group of researchers led by Skoltech Professor Pavel Troshin studied coordination polymers, a class of compounds with scarcely explored applications in metal-ion batteries, and demonstrated their possible future use in energy storage devices with a high charging/discharging rate and stability. The results of their study were published in the journal Chemistry of Materials.

The charging/discharging rate is one of the key characteristics of lithium-ion batteries. Most modern commercial batteries need at least an hour to get fully charged, which certainly limits the scope of their application, in particular, for electric vehicles. The trouble with active materials, such as the most popular anode material, graphite, is that their capacity decays significantly, as their charging rate increases. To retain the battery capacity at high charging rates, the active electrode materials must have high electronic and ionic conductivity, which is the case with the newly-discovered coordination polymers that are derived from and salts of , such as nickel or copper. Although these compounds hold a great promise, their application in lithium-ion batteries remains virtually unexplored.

A recent study undertaken by a group of scientists from Skoltech and the Institute for Problems of Chemical Physics of RAS led by Professor P. Troshin in collaboration with the University of Cologne (Germany) and the Ural Federal University, focused on tetraaminobenzene-based linear polymers of nickel and copper. Although the linear polymers exhibited much lower initial electronic conductivity as compared to their two-dimensional counterparts, it transpired that they can be used as anode materials that get charged/discharged in less than a minute, because their conductivity increases dramatically after the first discharge due to lithium doping.

Aug 10, 2019

New study in Science: Why humans in Africa fled to the mountains during the last ice age

Posted by in categories: biotech/medical, chemistry, science

People in Ethiopia did not live in low valleys during the last ice age. Instead they lived high up in the inhospitable Bale Mountains. There they had enough water, built tools out of obsidian and relied mainly on giant rodents for nourishment. This discovery was made by an international team of researchers led by Martin Luther University Halle-Wittenberg (MLU) in cooperation with the Universities of Cologne, Bern, Marburg, Addis Ababa and Rostock. In the current issue of “Science”, the researchers provide the first evidence that our African ancestors had already settled in the mountains during the Palaeolithic period, about 45,000 years ago.

At around 4,000 metres above sea level, the Bale Mountains in southern Ethiopia are a rather inhospitable region. There is a low level of oxygen in the air, temperatures fluctuate sharply, and it rains a lot. “Because of these adverse living conditions, it was previously assumed that humans settled in the Afro-Alpine region only very lately and for short periods of time,” says Professor Bruno Glaser, an expert in soil biogeochemistry at MLU. Together with an international team of archaeologists, soil scientists, palaeoecologists, and biologists, he has been able to show that this assumption is incorrect. People had already begun living for long periods of time on the ice-free plateaus of the Bale Mountains about 45,000 years ago during the Middle Pleistocene Epoch. By then the lower valleys were already too dry for survival.

For several years, the research team investigated a rocky outcrop near the settlement of Fincha Habera in the Bale Mountains in southern Ethiopia. During their field campaigns, the scientists found a number of stone artefacts, clay fragments and a glass bead. “We also extracted information from the soil as part of our subproject,” says Glaser. Based on the sediment deposits in the soil, the researchers from Halle were able to carry out extensive biomarker and nutrient analyses as well as radiocarbon dating and thus draw conclusions as to how many people lived in the region and when they lived there. For this work, the scientists also developed a new type of palaeothermometer which could be used to roughly track the weather in the region — including temperature, humidity and precipitation. Such analyses can only be done in natural areas with little contamination, otherwise the soil profile will have changed too much by more recent influences.

Aug 7, 2019

Physicists measure how electrons in transition metals get redistributed within fraction of optical oscillation cycle

Posted by in categories: chemistry, computing, particle physics

Researchers in the Department of Physics of ETH Zurich have measured how electrons in so-called transition metals get redistributed within a fraction of an optical oscillation cycle. They observed the electrons getting concentrated around the metal atoms within less than a femtosecond. This regrouping might influence important macroscopic properties of these compounds, such as electrical conductivity, magnetization or optical characteristics. The work therefore suggests a route to controlling these properties on extremely fast time scales.

The distribution of electrons in , which represent a large part of the periodic table of chemical elements, is responsible for many of their interesting properties used in applications. The magnetic properties of some of the members of this group of materials are, for example, exploited for data storage, whereas others exhibit excellent electrical conductivity. Transition metals also have a decisive role for novel materials with more exotic behaviour that results from strong interactions between the electrons. Such materials are promising candidates for a wide range of future applications.

In their experiment, whose results they report in a paper published today in Nature Physics, Mikhail Volkov and colleagues in the Ultrafast Laser Physics group of Prof. Ursula Keller exposed thin foils of the transition metals titanium and zirconium to short laser pulses. They observed the redistribution of the electrons by recording the resulting changes in optical properties of the metals in the extreme ultraviolet (XUV) domain. In order to be able to follow the induced changes with sufficient temporal resolution, XUV pulses with a duration of only few hundred attoseconds (10-18 s) were employed in the measurement. By comparing the experimental results with theoretical models, developed by the group of Prof. Angel Rubio at the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, the researchers established that the change unfolding in less than a femtosecond (10-15 s) is due to a modification of the electron localization in the vicinity of the metal atoms.

Aug 4, 2019

Antibiotic found in ocean could help beat superbugs

Posted by in categories: biotech/medical, chemistry, military

In the deep of the ocean, where the sun’s rays struggle to penetrate, organisms lurk that could solve the biggest medical crisis facing humanity.

Far below the surface bacteria are engaged in warfare with each other — and to do so they make an antibiotic so strong it can destroy the toughest superbugs in our hospitals.

“But there’s a problem,” Rebecca Goss, a professor of organic chemistry at the University of St Andrews, said. “It disintegrates in sunlight.”

Jul 30, 2019

Dr. Deborah Mash, Professor of Neurology and Molecular and Cellular Pharmacology, Director of the Brain Endowment Bank at the University of Miami, and CEO of DemeRx — Ira Pastor — ideaXme Show

Posted by in categories: aging, biotech/medical, business, chemistry, genetics, health, life extension, neuroscience, science, transhumanism

Jul 28, 2019

An Israeli Scientist Paves the Way to Alzheimer’s Cure, One Algorithm at a Time

Posted by in categories: biotech/medical, business, chemistry, information science, neuroscience

Scientists at work in laboratory. Photo: Public domain via Wikicommons.

CTech – When chemistry Nobel laureate Michael Levitt met his wife two years ago, he didn’t know it would lead to a wonderful friendship with a young Israeli scientist. When Israeli scientist Shahar Barbash decided to found a startup with the aim of cutting down the time needed to develop new medicine, he didn’t know that a friend’s wedding would help him score a meeting with a man many want to meet but few do. But Levitt’s wife is an old friend of Barbash’s parents, and the rest, as they say, is history.

One of the joys of being an old scientist is to encourage extraordinary young ones, Levitt, an American-British-Israeli biophysicist and a professor at Stanford University since 1987, said in a recent interview with Calcalist. He might have met Barbash because his wife knew his family, but that is not enough to make him go into business with someone, Levitt said. “I got on board because his vision excited me, even though I thought it would be very hard to realize.”

Jul 26, 2019

Virginia Tech researchers lead breakthrough in quantum computing

Posted by in categories: chemistry, computing, information science, quantum physics

Abstract: The large, error-correcting quantum computers envisioned today could be decades away, yet experts are vigorously trying to come up with ways to use existing and near-term quantum processors to solve useful problems despite limitations due to errors or “noise.”

A key envisioned use is simulating molecular properties. In the long run, this can lead to advances in materials improvement and drug discovery. But not with noisy calculations confusing the results.

Now, a team of Virginia Tech chemistry and physics researchers have advanced quantum simulation by devising an algorithm that can more efficiently calculate the properties of molecules on a noisy quantum computer. Virginia Tech College of Science faculty members Ed Barnes, Sophia Economou, and Nick Mayhall recently published a paper in Nature Communications detailing the advancement.

Jul 24, 2019

Towards a light driven molecular assembler

Posted by in categories: biological, chemistry, nanotechnology, physics

A team of chemists built the first artificial assembler, which uses light as the energy source. These molecular machines are performing synthesis in a similar way as biological nanomachines. Advantages are fewer side products, enantioselectivity, and shorter synthetic pathways since the mechanosynthesis forces the molecules into a predefined reaction channel.

Chemists usually synthesize molecules using stochastic bond-forming collisions of the reactant molecules in solution. Nature follows a different strategy in biochemical synthesis. The majority of biochemical reactions are driven by machine-type protein complexes that bind and position the reactive molecules for selective transformations. Artificial “molecular assemblers” performing “mechanosynthesis” have been proposed as a new paradigm in chemistry and nanofabrication. A team of chemists at Kiel University (Germany) built the first artificial assembler, that performs synthesis and uses light as the energy source. The system combines selective binding of the reactants, accurate positioning, and active release of the product. The scientists published their findings in the journal Communications Chemistry.

The idea of molecular assemblers, that are able to build molecules, has already been proposed in 1986 by K. Eric Drexler, based on ideas of Richard Feynman, Nobel Laureate in Physics. In his book “Engines of Creation: The Coming Era of Nanotechnology” and follow-up publications Drexler proposes molecular machines capable of positioning reactive molecules with atomic precision and to build larger, more sophisticated structures via mechanosynthesis. If such a molecular nanobot could build any molecule, it could certainly build another copy of itself, i.e. it could self-replicate. These imaginative visions inspired a number of science fiction authors, but also started an intensive scientific controversy.

Jul 22, 2019

Panic Attacks and Anxiety Episodes Linked to Vitamin Deficiencies in Groundbreaking Study

Posted by in categories: biotech/medical, chemistry, genetics, health, neuroscience

HELLO! https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6025786/


With approximately 40 million adults across the United States experiencing anxiety each year, scientists and researchers have dedicated their careers to trying to better understand this condition. Despite this work, we are still somewhat unclear on what actually causes this condition to occur.

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