Lifeboat Foundation: Safeguarding Humanity
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Category: chemistry – Page 299

The population on Earth is increasingly growing and people are expected to live longer in the future. Thus, better and more reliable therapies to treat human diseases such as Alzheimer’s and cardiovascular diseases are crucial. To cope with the challenge of ensuring healthy aging, a group of international scientists investigated the potential of biosynthesising several polyamines and polyamines analogs with already known functionalities in treating and preventing age-related diseases.

One of the most interesting molecules to study was spermidine, which is a natural product already present in people’s blood and an inducer of autophagy that is an essential cellular process for clearing damaged proteins, e.g., misfolded proteins in brain cells that can cause Alzheimer’s. When people get older the level of spermidine in the blood decrease and dietary supplements, or certain are needed to maintain a stable and high level of spermidine in the blood. However, those products are difficult to produce with traditional chemistry due to their structural complexity and extraction of natural resources is neither a commercially viable nor a sustainable approach.

Therefore, the researchers instead decided to open their biochemical toolbox and use classical metabolic engineering strategies to engineer the yeast metabolism to produce polyamines and polyamines analogs.

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Possibly one of the most surprising ways in which our mind and body are interlinked with one another is the gut-brain axis, which is a collection of bidirectional biochemical signals which are transmitted between the nervous system of the body and the digestive system. This is understandably surprising, as the functions of these two distinct parts of the body are completely different to one another. The gut is unlike most other parts of the body, because a large part of its function and health is dictated by cells which are not part of the body, but are instead bacteria cells which colonise the inner lining of the gut.

It has been known for a while now that the makeup of the gut flora changes as we age, which has in turn been linked to cognitive decline through the disruption of the aforementioned gut-brain axis. It has even been shown that faecal transplants can help to correct this cognitive decline in mice, and has been shown to be able to generate a direct positive effect on cognitive function.

Further research into this phenomenon has revealed that the graduate degradation of the gut flora, or more commonly referred to as the ‘good’ bacteria inside the gut has revealed that these bacteria play an important role at keeping unwanted bacteria in check. Researchers at the University Of Florida have found that certain types of ‘good’ bacteria inside the gut produce a chemical known as butyrate, which supresses the growth of pathogenic bacteria such as Enterobacteriaceae. These pathogenic, or ‘bad’ bacteria effect the body in numerous ways, such as interfering with the protein folding, resulting in a build up of toxic and mis-formed proteins within the body. This disruption to protein folding causes problems all across the body, including in the muscles, intestines, gonads, and most notably the brain and central nervous system.

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The World Health Organization classifies processed meat as a Group 1 carcinogen. Processed meat includes ham, sausage, bacon, pepperoni; they’re meats that have been preserved with salt or smoke, meat that has been cured, and meat treated with chemical preserves. Other Group 1 carcinogens include formaldehyde, tobacco, and UV radiation. Group 1 carcinogens have ‘enough evidence to conclude that it can cause cancer in humans.’

There is no question whether or not our current meat production complex is inhumane, unsanitary, or bad for the environment. Almost all chickens (99.9%), turkeys (99.8%), and most cows (70.4%) eaten in the United States are raised on factory farms. There are horrific consequences to this practice.

For example, the EPA estimates agriculture is the biggest contaminator of rivers and streams, to the point where feedlots, crop production, and manure runoff have led almost half (46%) of the U.S.’s rivers to be “in poor biological condition.”

Scientific American also explains, “TDM-approved feed containing antibiotics [are] a necessity if [factory farm animals] were to stay healthy in their crowded, manure-gilded home. Antibiotics also help farm animals grow faster on less food, so their use has long been a staple of industrial farming.” Many scientists worry that antibiotics used at such a scale on farms create unstoppable, drug-resistant bacteria that can transfer to humans; think inconveniences like nose infections or UTIs turned deadly because of the lack of antibiotics available to treat them.

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The way the team made the human–monkey embryo is similar to previous attempts at half-human chimeras.

Here’s how it goes. They used de-programmed, or “reverted,” human stem cells, called induced pluripotent stem cells (iPSCs). These cells often start from skin cells, and are chemically treated to revert to the stem cell stage, gaining back the superpower to grow into almost any type of cell: heart, lung, brain…you get the idea. The next step is preparing the monkey component, a fertilized and healthy monkey egg that develops for six days in a Petri dish. By this point, the embryo is ready for implantation into the uterus, which kicks off the whole development process.

This is where the chimera jab comes in. Using a tiny needle, the team injected each embryo with 25 human cells, and babied them for another day. “Until recently the experiment would have ended there,” wrote Drs. Hank Greely and Nita Farahany, two prominent bioethicists who wrote an accompanying expert take, but were not involved in the study.

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Circa 2019

As quantum computing enters the industrial sphere, questions about how to manufacture qubits at scale are becoming more pressing. Here, Fernando Gonzalez-Zalba, Tsung-Yeh Yang and Alessandro Rossi explain why decades of engineering may give silicon the edge.

In the past two decades, quantum computing has evolved from a speculative playground into an experimental race. The drive to build real machines that exploit the laws of quantum mechanics, and to use such machines to solve certain problems much faster than is possible with traditional computers, will have a major impact in several fields. These include speeding up drug discovery by efficiently simulating chemical reactions; better uses of “big data” thanks to faster searches in unstructured databases; and improved weather and financial-market forecasts via smart optimization protocols.

We are still in the early stages of building these quantum information processors. Recently, a team at Google has reportedly demonstrated a quantum machine that outperforms classical supercomputers, although this so-called “quantum supremacy” is expected to be too limited for useful applications. However, this is an important milestone in the field, testament to the fact that progress has become substantial and fast paced. The prospect of significant commercial revenues has now attracted the attention of large computing corporations. By channelling their resources into collaborations with academic groups, these firms aim to push research forward at a faster pace than either sector could accomplish alone.

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Researchers have developed a way to dynamically switch the surface of liquidmetal between reflective and scattering states. This technology could one day be used to create electrically controllable mirrors or illumination devices.

Liquid metals combine the electrical, thermal and optical properties of metals with the fluidity of a liquid. The new approach uses an electrically driven chemical reaction to create switchable reflective surfaces on a . No nor polishing steps, which are typically required to make reflective optical components, are necessary to make the liquid metal highly reflective.

In the Optical Society (OSA) journal Optical Materials Express, researchers led by Yuji Oki of Kyushu University in Japan show that switching between reflective and scattering states can be achieved with just 1.4 V, about the same voltage used to light a typical LED. The researchers collaborated with Michael D. Dickey’s research team at North Carolina State University to develop the new method, which can be implemented at and pressures.

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Circa 2018

The death-cap mushroom has a long history as a tool of murder and suicide, going back to ancient Roman times. The fungus, Amanita phalloides, produces one of the world’s deadliest toxins: α-amanitin. While it may seem ill-advised, researchers are eager to synthesize the toxin because studies have shown that it could help fight cancer. Scientists now report in the Journal of the American Chemical Society how they overcame obstacles to synthesize the death-cap killer compound.

α-Amanitin achieves its impressive deadliness by acting as a potent inhibitor of RNA polymerase II, the enzyme primarily responsible for transcribing genes into the messenger molecule RNA. Using α-amanitin bound to antibodies against tumor molecules, cancer researchers have reportedly cured mice of pancreatic cancer. These conjugates are currently in human trials; however, the only way to obtain α-amanitin so far has been to harvest mushrooms, which is time-consuming and results in relatively small amounts of the compound. Synthetic production approaches have been hampered by α-amanitin’s unusual bicyclic structure, among other tricky features. David M. Perrin and colleagues decided to take on the challenge to produce the toxin in the laboratory, once and for all.

The researchers had to work through three key obstacles to produce α-amanitin in the laboratory: production of the “oxidatively delicate” 6-hydroxy-tryptathionine, the an enantio-selective synthesis of (2 S, 3 R, 4 R)-4, 5-dihydroxy-isoleucine and a diastereoselective sulfoxidation to favor the (R)-sulfoxide. Due to its toxic nature, the researchers limited production to less than a milligram, but based on their results, they are confident that good yields are can be readily obtained by scaling up the process. The researchers also say that the development of this synthetic route will enable chemists to attenuate the toxicity and potentially improve α-amanitin’s activity against cancer, something that is only made possible by the use of synthetic derivatives.

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A long-held goal by chemists across many industries, including energy, pharmaceuticals, energetics, food additives and organic semiconductors, is to imagine the chemical structure of a new molecule and be able to predict how it will function for a desired application. In practice, this vision is difficult, often requiring extensive laboratory work to synthesize, isolate, purify and characterize newly designed molecules to obtain the desired information.

Recently, a team of Lawrence Livermore National Laboratory (LLNL) materials and computer scientists have brought this vision to fruition for energetic molecules by creating machine learning (ML) models that can predict molecules’ crystalline properties from their alone, such as molecular density. Predicting crystal structure descriptors (rather than the entire crystal structure) offers an efficient method to infer a material’s properties, thus expediting materials design and discovery. The research appears in the Journal of Chemical Information and Modeling.

“One of the team’s most prominent ML models is capable of predicting the crystalline density of energetic and energetic-like molecules with a high degree of accuracy compared to previous ML-based methods,” said Phan Nguyen, LLNL applied mathematician and co-first author of the paper.

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