Lifeboat Foundation: Safeguarding Humanity
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Category: biotech/medical

First discovered in 1984, retrons are floating ribbons of DNA in some bacteria cells that can be converted into a specific type of DNA—a single chain of DNA bases dubbed ssDNAs (yup, it’s weird). But that’s fantastic news for gene editing, because our cells’ double-stranded DNA sequences become impressionable single chains when they divide. Perfect timing for a retron bait-and-switch.

Normally, our DNA exists in double helices that are tightly wrapped into 23 bundles, called chromosomes. Each chromosome bundle comes in two copies, and when a cell divides, the copies separate to duplicate themselves. During this time, the two copies sometimes swap genes in a process called recombination. This is when retrons can sneak in, inserting their ssDNA progeny into the dividing cell instead. If they carry new tricks—say, allowing a bacteria cell to become resistant against drugs—and successfully insert themselves, then the cell’s progeny will inherit that trait.

Because of the cell’s natural machinery, retrons can infiltrate a genome without cutting it. And they can do it in millions of dividing cells at the same time.

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Widely used to monitor and map biological signals, to support and enhance physiological functions, and to treat diseases, implantable medical devices are transforming healthcare and improving the quality of life for millions of people. Researchers are increasingly interested in designing wireless, miniaturized implantable medical devices for in vivo and in situ physiological monitoring. These devices could be used to monitor physiological conditions, such as temperature, blood pressure, glucose, and respiration for both diagnostic and therapeutic procedures.

To date, conventional implanted electronics have been highly volume-inefficient—they generally require multiple chips, packaging, wires, and external transducers, and batteries are often needed for . A constant trend in electronics has been tighter integration of electronic components, often moving more and more functions onto the integrated circuit itself.

Researchers at Columbia Engineering report that they have built what they say is the world’s smallest single– system, consuming a total volume of less than 0.1 mm3. The system is as small as a dust mite and visible only under a microscope. In order to achieve this, the team used ultrasound to both power and communicate with the device wirelessly. The study was published online May 7 in Science Advances.

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Not sure how novel.

People who live beyond 105 years are more efficient at repairing DNA, according to a study published today in eLife.

Paolo Garagnani and colleagues, in collaboration with several research groups in Italy and a research team led by Patrick Descombes at Nestlé Research in Lausanne, Switzerland, recruited 81 semi-supercentenarians (those aged 105 years or older) and supercentenarians (those aged 110 years or older) from across the Italian peninsula. They compared these with 36 healthy people matched from the same region who were an average age of 68 years old.

They took blood samples from all the participants and conducted whole-genome sequencing to look for differences in the genes between the older and younger group. They then cross-checked their new results with genetic data from another previously published study which analyzed 333 Italian people aged over 100 years old and 358 people aged around 60 years old.

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A gene therapy that makes use of an unlikely helper, the AIDS virus, gave a working immune system to 48 babies and toddlers who were born without one, doctors reported Tuesday.

Results show that all but two of the 50 children who were given the experimental therapy in a study now have healthy germ-fighting abilities.

“We’re taking what otherwise would have been a fatal disease” and healing most of these children with a single treatment, said study leader Dr. Donald Kohn of UCLA Mattel Children’s Hospital.

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Only one in three fertilizations leads to a successful pregnancy. Many embryos fail to progress beyond early development. Cell biologists at the Max Planck Institute (MPI) for Biophysical Chemistry in Göttingen (Germany), together with researchers at the Institute of Farm Animal Genetics in Mariensee and other international colleagues, have now developed a new model system for studying early embryonic development. With the help of this system, they discovered that errors often occur when the genetic material from each parent combines immediately after fertilization. This is due to a remarkably inefficient process.

Human somatic cells typically have 46 , which together carry the genetic information. These chromosomes are first brought together at fertilization, 23 from the father’s sperm, and 23 from the mother’s egg. After fertilization, the parental chromosomes initially exist in two separate compartments, known as pronuclei. These pronuclei slowly move towards each other until they come into contact. The pronuclear envelopes then dissolve, and the parental chromosomes unite.

The majority of human embryos, however, end up with an incorrect number of chromosomes. These embryos are often not viable, making erroneous genome unification a leading cause of miscarriage and infertility.

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Many organisms and tissues display the ability to heal and regenerate as needed for normal physiology and as a result of pathogenesis. However, these repair activities can also be observed at the single-cell level. The physical and molecular mechanisms by which a cell can heal membrane ruptures and rebuild damaged or missing cellular structures remain poorly understood. This Review presents current understanding in wound healing and regeneration as two distinct aspects of cellular self-repair by examining a few model organisms that have displayed robust repair capacity, including Xenopus oocytes, Chlamydomonas, and Stentor coeruleus. Although many open questions remain, elucidating how cells repair themselves is important for our mechanistic understanding of cell biology. It also holds the potential for new applications and therapeutic approaches for treating human disease.

Cells are generally soft and easily damaged. However, many can repair themselves after being punctured, torn, or even ripped in half when damaged during the ordinary wear and tear of normal physiology or as a result of injury or pathology. A cell is like a spacecraft: When it is punctured, cytoplasm spills out like oxygen escaping from a damaged space module. Like Apollo 13, a damaged cell cannot rely on anyone to fix it. It must repair itself, first by stopping the loss of cytoplasm, and then regenerate by rebuilding structures that were damaged or lost. Knowledge of how single cells repair and regenerate themselves underpins our mechanistic understanding of cell biology and could guide treatments for conditions involving cellular damage.

A standard question that students are asked is to define what it means to be alive. This is surprisingly hard to answer in a precise way, but surely one of the remarkable features of living systems that distinguishes them from human-made machines is their ability to heal and repair themselves. At the multicellular level, repair and regeneration are effected by generating new cells to replace the ones that were lost. This type of repair thus ends up being a direct consequence of another basic feature of living systems—the ability of a cell to reproduce itself. No additional processes need to be invoked beyond cell division. At the single-cell level, it is much less obvious how self-repair is accomplished.

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TOKYO — India is rapidly closing the gap with China in minting new unicorns — privately held startups valued at $1 billion or more — highlighting growing investor appetite for tech startups in the country as the pandemic accelerates adoption of digital services.

Over the past year, 15 companies from India raised capital at a valuation of $1 billion or more for the first time, according to CB Insights and company announcements gathered by Nikkei Asia. Ten of them became unicorns in 2021. By comparison, only two of the 16 companies from China that joined the list over the past year did so in 2021, according to CB Insights.

A successful listing of online food delivery company Zomato, which recently filed a draft prospectus with India’s securities regulator, would set the stage for many of these unicorns to follow suit. Zomato, a loss-making company operating in a nascent industry once considered too risky to invest, is planning to raise 82.5 billion rupees ($1.1 billion), including through a pre-IPO placement.

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This new species, Desulfovibrio diazotrophicus, is from a family of bacteria that survive and grow on sulfur-containing compounds. They are known as sulfate-reducing bacteria (SRB) and a biproduct of their activity is the release of the gas hydrogen sulfide, which has a characteristic ‘rotten egg’ smell. Whilst this is unpleasant for those around you, there is also some concern that it is detrimental for gut health; the presence of SRB has been associated with gut inflammation, inflammatory bowel disease (IBD) and colorectal cancer.

Despite this, evidence for a definitive link between SRB and chronic disease has never been established. For a start, they are very widespread; around half the human population have SRB in their gut, so maybe not all of them are bad? They may even have positive effects. They release energy and nutrients from the material that other bacteria produce when they are fermenting the food we eat.

This uncertainty triggered interest from the , including scientists from the Quadram Institute (QI), who want to understand exactly what SRB do in the microbiome and how they interact with food and the gut. Very few species have been characterized, most from Western countries. To broaden the picture, QI researchers have been working with Professor Chen Wei and colleagues from Jiangnan University, China to isolate and characterize SRB from the intestinal tract of healthy Chinese and British people. The research was funded by the Biotechnology and Biological Sciences Research Council, part of UKRI.

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