A new hope for a therapy against retinitis pigmentosa

Retinitis pigmentosa is the most common hereditary retinal disease in humans, with a prevalence of one in every 4,000 people worldwide.
Photo by Danish Ahmad

Retinitis pigmentosa, a degenerative genetic disease of the eye, is characterized by progressive vision loss, usually leading to blindness. In some patients, structural defects in the photoreceptor cells have been observed, but the molecular mechanisms involved are not understood. A team from the University of Geneva (UNIGE), in collaboration with the University of Lausanne (UNIL), has identified the essential role played by a molecular zipper formed by four proteins. The absence of this zipper leads to cell death in retinal cells. This discovery could lead to the development of therapeutic approaches for retinitis pigmentosa. This work can be read in the journal PLOS Biology.

Retinitis pigmentosa is the most common hereditary retinal disease in humans, with a prevalence of one in every 4,000 people worldwide. The first symptoms usually appear between the ages of 10 and 20 with a loss of night vision. Thereafter, the visual field narrows into a “tunnel vision” to finally lead to blindness around the age of 40. This disease is characterized by a degeneration of the light sensitive cells, the photoreceptors.

These specialized neuronal cells of the retina are responsible for the conversion of light into a nerve signal. The outer segment of the cell is made up of stacks of discs on which the light-sensitive pigments are located. The inner segment contains all the metabolic machinery essential to the functioning of the cell and is linked to the outer segment by the connecting cilium.

Flawed research not retracted fast enough to prevent spread of misinformation

People who engage with research critically on Twitter may contribute to valuable conservations about science, new research suggests.
Illustration by ijmaki via Pixabay

A new analysis by Northwestern University and University of Michigan researchers suggests retracting academic papers does not dampen the reach of problematic research as intended. Instead, papers that are later retracted are often widely circulated online, both by news outlets and social media, and the cycle of attention that they receive typically dies away before the retraction even happens.

The finding has concerning implications for the spread of misinformation and public trust in science. However, retracted papers included in the analysis were often the subject of more critical discourse on Twitter before their retraction, suggesting that while Twitter should not be an official judge of science, it’s possible that in some communities, it could provide early signals of dubious research.

When a paper is retracted, the goal is to officially discredit it and acknowledge the research as flawed, thereby maintaining the overall integrity of the research enterprise. However, many people who hear about the initial finding may never learn of the retraction.

“Social media and even top news outlets — the most prestigious venues that cover science — are more prone to talk about papers that end up being retracted,” said Ágnes Horvát, an assistant professor of communication and computer science at Northwestern who was an author on the paper, published in the Proceedings of the National Academy of Sciences.

Going Platinum: A Non-Toxic Catalyst for Clean, Re-Usable Water

Harmful aldehydes (found in treated wastewater can be transformed to carboxylic acids by using the existing oxygen found in water and platinum as a catalyst to speed up the reaction. note: The reaction scheme shown appears not to be balanced. The illustration is used to simplify the presentation of the multiple reactions occurring and which are balanced. details are available in the material cited.
Image Credit: Daniel McCurry.

Platinum has set a new “gold standard” in jewelry, and now it’s about to upscale the quality of your water.

As wastewater treatment for potable – drinkable – reuse becomes a more viable and popular option to address water shortages, the question of what harmful byproducts might form in treatment and how to address them looms large. One group of these chemicals, aldehydes, are known to stubbornly persist through treatment. Toxic to humans, aldehydes will be at the top of the list of regulated byproducts in forthcoming reuse regulations, USC researchers believe, and require sustainable methodology to be removed from our drinking water.

In research published in Environmental Science & Technology, USC Viterbi School of Engineering researchers introduced platinum to help clean even the most stubborn toxins from wastewater. Platinum, the same metal used in catalytic converters to clean up air pollutants in car exhaust, can serve as a catalyst, said Dan McCurry, assistant professor in civil and environmental engineering, speeding up oxidation to transform once-toxic aldehydes into harmless carboxylic acids.

New research on dust mites and respiratory infections

Lena Uller
Credit: Agata Garpenlind

When asthmatics’ respiratory tracts are exposed to dust mites, their immune response becomes less effective, which can lead to a weaker immune system. People who suffer from asthma associated with infection may therefore be more susceptible to secondary viral or bacterial infections. According to the researchers, the results suggest that asthmatics should avoid house dust mites and that patients who are also allergic to the mites should consider undergoing so-called hyposensitization. The study was recently published in Allergy.

In an earlier study, Professor Lena Uller and her research team have shown that house dust mites, when compared to other common allergens, give rise to a more powerful inflammatory response in the epithelium cells in the lungs of asthmatics. These epithelium cells are a barrier intended to protect the lungs from harmful microbes and particles that we breathe in.

Clinical data has shown that asthma patients with allergies are more frequently prescribed antibiotics, compared to non-allergic asthmatics, according to Samuel Cerps, first author of the study, which was part of the doctoral thesis he submitted in late May.

“This suggests that allergy is a risk factor in bacterial infections and that got us interested in studying how exposure to house dust mites affects the immune system of asthmatics,” says Cerps.

Using bronchial brushing, the researchers collected and cultivated epithelial cells from asthmatics including those with and without a dust mite allergy. The cells were then exposed to dust mites for 24 hours before being exposed to a virus. Through this method, the researchers were able to investigate how a viral infection affects the immune system in terms of both viral and bacterial infections.

Tenascin proteins inhibit cell sheath regeneration

Juliane Bauch (left) and Andreas Faissner from the Chair of Cell Morphology and Molecular Neurobiology
Credit: RUB, Kramer

In multiple sclerosis, nerve cells lose their insulating layer. Researchers from Bochum are looking for starting points to promote regeneration processes. They have identified two relevant proteins.

Researchers at the Ruhr University Bochum have investigated the role that the two proteins tenascin C and tenascin R play in multiple sclerosis. In the disease, cells of the immune system destroy the myelin sheaths, i.e. the sheathing of the nerve cells. As the Bochum team showed in experiments with mice, the presence of the two Tenascins inhibits the regeneration of the myelin sheaths. Dr. Juliane Bauch and Prof. Dr. Andreas Faissner from the Bochum Chair for Cell Morphology and Molecular Neurobiology describes the results in the journal Cells.

The cause of the destruction of myelin sheaths in multiple sclerosis has not yet been clarified. "But the organism has various mechanisms to partially compensate for the lesions," says Juliane Bauch, who dealt intensively with the topic in her doctorate. The aim of the work is to identify starting points with which the regeneration of myelin sheaths could be improved.

Experiment results confirm anomaly suggesting new physics possibility

Located deep underground at the Baksan Neutrino Observatory in the Caucasus mountains in Russia, the completed two-zone gallium target, at left, contains an inner and outer tank of gallium, which is irradiated by an electron neutrino source.
image resized using AI by SFLORG
Credit: A.A. Shikhin

New scientific results confirm an anomaly seen in previous experiments, which may point to an as-yet-unconfirmed new elementary particle, the sterile neutrino, or indicate the need for a new interpretation of an aspect of standard model physics, such as the neutrino cross section, first measured 60 years ago. Los Alamos National Laboratory is the lead American institution collaborating on the Baksan Experiment on Sterile Transitions (BEST) experiment, results of which were recently published in the journals Physical Review Letters and Physical Review C.

“The results are very exciting,” said Steve Elliott, lead analyst of one of the teams evaluating the data and a member of Los Alamos’ Physics division. “This definitely reaffirms the anomaly we’ve seen in previous experiments. But what this means is not obvious. There are now conflicting results about sterile neutrinos. If the results indicate fundamental nuclear or atomic physics are misunderstood, that would be very interesting, too.” Other members of the Los Alamos team include Ralph Massarczyk and Inwook Kim.

More than a mile underground in the Baksan Neutrino Observatory in Russia’s Caucasus Mountains, BEST used 26 irradiated disks of chromium 51, a synthetic radioisotope of chromium and the 3.4 megacurie source of electron neutrinos, to irradiate an inner and outer tank of gallium, a soft, silvery metal also used in previous experiments, though previously in a one-tank set-up. The reaction between the electron neutrinos from the chromium 51 and the gallium produces the isotope germanium 71.

Martian Meteorite Upsets Planet Formation Theory

When our solar system formed, Mars formed earlier than Earth, and its composition gives clues about early steps in planet formation. A new UC Davis study overturns previous ideas about how rocky planets form.
Credit: NASA

A new study of an old meteorite contradicts current thinking about how rocky planets like the Earth and Mars acquire volatile elements such as hydrogen, carbon, oxygen, nitrogen and noble gases as they form. The work is published June 16 in Science.

A basic assumption about planet formation is that planets first collect these volatiles from the nebula around a young star, said Sandrine Péron, a postdoctoral scholar working with Professor Sujoy Mukhopadhyay in the Department of Earth and Planetary Sciences, University of California, Davis.

Because the planet is a ball of molten rock at this point, these elements initially dissolve into the magma ocean and then degas back into the atmosphere. Later on, chondritic meteorites crashing into the young planet deliver more volatile materials.

So, scientists expect that the volatile elements in the interior of the planet should reflect the composition of the solar nebula, or a mixture of solar and meteoritic volatiles, while the volatiles in the atmosphere would come mostly from meteorites. These two sources — solar vs. meteoritic — can be distinguished by the ratios of isotopes of noble gases, in particular krypton.

Mars is of special interest because it formed relatively quickly — solidifying in about 4 million years after the birth of the solar system, while the Earth took 50 to 100 million years to form.

“We can reconstruct the history of volatile delivery in the first few million years of the solar system,” Péron said.

Can computers understand complex words and concepts?

 A depiction of semantic projection, which can determine the similarity between two words in a specific context. This grid shows how similar certain animals are based on their size.
Credit: Idan Blank/UCLA 

In “Through the Looking Glass,” Humpty Dumpty says scornfully, “When I use a word, it means just what I choose it to mean — neither more nor less.” Alice replies, “The question is whether you can make words mean so many different things.”

The study of what words really mean is ages old. The human mind must parse a web of detailed, flexible information and use sophisticated common sense to perceive their meaning.

Now, a newer problem related to the meaning of words has emerged: Scientists are studying whether artificial intelligence can mimic the human mind to understand words the way people do. A new study by researchers at UCLA, MIT and the National Institutes of Health addresses that question.

The paper, published in the journal Nature Human Behavior, reports that artificial intelligence systems can indeed learn very complicated word meanings, and the scientists discovered a simple trick to extract that complex knowledge. They found that the AI system they studied represents the meanings of words in a way that strongly correlates with human judgment.

The AI system the authors investigated has been frequently used in the past decade to study word meaning. It learns to figure out word meanings by “reading” astronomical amounts of content on the internet, encompassing tens of billions of words.

Scientists fail to locate once-common CA bumble bees

The Western bumble bee, a once-common bee in California, was not found in the recent UCR-led survey.
resized using AI by SFLORG
Credit: Rich Hatfield/Xerces Society

Several species of California bumble bees have gone missing in the first statewide census of the fuzzy pollinators in 40 years. If they can be found, a recent court ruling could help save them.

Smaller-scale studies have documented significant declines in bumble bee populations around the world due to climate change, development of wild habitat, and the use of bee-killing pesticides.

Led by UC Riverside, this study was an effort to document changes in bumble bee populations across large geographic areas in California since the last such study was done in the 1980s.

It is important to have data that substantiates the bees’ health. Bumble bees can fly in cooler temperatures and lower light levels than many other bees, and help pollinate crops worth $3 billion annually in the U.S. They perform a type of pollination required for plants including tomatoes, peppers and cranberries.

For the updated data, UCR entomologist Hollis Woodard’s research group collected bees from 17 total sites representing six different ecosystems previously known to host a large variety of bumble bees.

Molecular 3D-maps unlock new ways of studying human reproduction

The study also provides a crucial reference for fetal tissue generation in the lab - such tissue is in short supply but is needed for drug screening and studies into stem cell-based treatments to regenerate body tissues in diseases like Parkinson’s, for example.

Embryos develop from a clump of cells into highly organized structures. However, until now the signals orchestrating this transformation have remained hidden from observation inside the womb.

Measuring gene activity in three dimensions, researchers have generated molecular maps of the second week of gestation as it has never been seen before. Their work is published today in the journal Nature.

“This work will provide a definitive laboratory reference for future studies of early embryo development, and the embryonic origins of disease,” said Dr Thorsten Boroviak in the University of Cambridge’s Department of Physiology, Development and Neuroscience and senior author of the study.

The second week of gestation is one of the most mysterious, yet critical, stages of embryo development. Failure of development during this time is one of the major causes of early pregnancy loss and birth defects.

In previous work, Boroviak showed that the first week of development in marmoset monkeys is remarkably similar to that in humans. But with existing methods he could not explore week two of development, after the embryo implants into the womb.