. Scientific Frontline

Tuesday, March 7, 2023

COVID-19 infections raise risk of long-term gastrointestinal problems

Ziyad Al-Aly, MD, has led multiple studies on long COVID-19 as a clinical epidemiologist at Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care system. His latest findings show that people who have been infected with COVID-19 are at an increased risk of developing a range of gastrointestinal conditions within the first month to a year after illness.
Photo Credit: Matt MIller / School of Medicine / Washington University in St. Louis

People who have had COVID-19 are at increased risk of developing gastrointestinal (GI) disorders within a year after infection compared with people who haven’t been infected, according to an analysis of federal health data by researchers at Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care system.

Such conditions include liver problems, acute pancreatitis, irritable bowel syndrome, acid reflux and ulcers in the lining of the stomach or upper intestine. The post-COVID-19 GI tract also is associated with an increased likelihood of constipation, diarrhea, abdominal pain, bloating and vomiting.

“Gastrointestinal problems were among the first that were reported by the patient community,” said senior author Ziyad Al-Aly, MD, a clinical epidemiologist at Washington University who has studied extensively the long-term effects of COVID-19 infection. “It is increasingly clear that the GI tract serves as a reservoir for the virus.”

Blood test identifies acute myeloid leukemia patients at greater risk for relapse after bone marrow transplant

Photo Credit: Tatiana

A small portion of adults in remission from a deadly blood cancer had persisting mutations that were detected, which predicted their risk of death from having the cancer return.

Researchers at the National Institutes of Health show the benefits of screening adult patients in remission from acute myeloid leukemia (AML) for residual disease before receiving a bone marrow transplant. The findings, published in JAMA, support ongoing research aimed at developing precision medicine and personalized post-transplant care for these patients.

About 20,000 adults in the United States are diagnosed each year with AML, a deadly blood cancer, and about one in three live past five years. A bone marrow transplant, which replaces unhealthy blood-forming cells with healthy cells from a donor, often improves these chances. However, research has shown that lingering traces of leukemia can make a transplant less effective. 

Researchers in the current study wanted to show that screening patients in remission for evidence of low levels of leukemia using standardized genetic testing could better predict their three-year risks for relapse and survival. To do that, they used ultra-deep DNA sequencing technology to screen blood samples from 1,075 adults in remission from AML. All were preparing to have a bone marrow transplant. The study samples were provided through donations to the Center for International Blood and Marrow Transplant Research.

Laser shots at National Ignition Facility could spark additional discoveries in astrophysics

Image of the Crab Nebula, a remnant of a supernova explosion. Scientists are studying the extreme environments in supernovae to understand where the heavy elements came from.
Image Credit: NASA, ESA, J. Hester, A. Loll (ASU)

In December, the National Ignition Facility (NIF) at the U.S. Department of Energy’s (DOE) Lawrence Livermore National Laboratory made headlines worldwide. Scientists at the NIF performed the first nuclear fusion experiment in which the energy produced from fusion exceeded the amount of energy directly applied to the fuel to ignite it. This first-of-its-kind result will provide invaluable insight into the potential for clean energy from fusion. 

But the NIF’s scientific impact doesn’t end there. Using the Argonne Tandem Linac Accelerator System (ATLAS), a DOE Office of Science user facility located at DOE’s Argonne National Laboratory, a team of scientists is studying the extreme, star-like environment created during laser shots at the NIF to better understand its potential as a testbed for nuclear astrophysics research. The work could also provide insight into the nature of stars and the origin of the elements. 

“If we can reproduce these astrophysical conditions on earth in a laboratory, we can study stellar processes in detail in a well-characterized environment close to home.” — ATLAS user Michael Paul, Hebrew University of Jerusalem 

Does current shellfish culture gear curb ‘crunching’ rays?

Whitespotted eagle rays “crunching” on clams in a large outdoor tank with clams housed within a variety of anti-predator materials.
Video Credit: Florida Atlantic University / Harbor Branch Oceanographic Institute 

According to NOAA Fisheries, more than 80 percent of marine aquaculture production in the United States consists of bivalve mollusks such as oysters, clams and mussels. However, it’s not just humans who enjoy eating these shellfish, so do marine rays. They like to “crunch” on clams, which can sometimes take a big bite out of clammers’ profits.

Part of the process of culturing hard clams (Mercenaria mercenaria) involves deploying them in submerged bottom leases in the marine environment where clams can grow to market size. When deployed onto the clam lease, clammers incorporate a variety of anti-predator materials to protect their product, such as woven mesh netting and/or additional mesh, plastic or wire covers.

However, the effectiveness of these materials against highly mobile predators like rays has not been experimentally tested. Some rays, like the whitespotted eagle ray (Aetobatus narinari), are equipped with strong jaws, plate-like teeth and nimble pectoral fins, which make them formidable and highly maneuverable predators of clams.

Plastic containers can contain PFAS — and it’s getting into food

Illustration Credit: University of Notre Dame

Researchers at the University of Notre Dame are adding to their list of consumer products that contain PFAS (per- and polyfluoroalkyl substances), a toxic class of fluorine compounds known as “forever chemicals.”

In a new study published in Environmental Science and Technology Letters, fluorinated high-density polyethylene (HDPE) plastic containers — used for household cleaners, pesticides, personal care products and, potentially, food packaging — tested positive for PFAS. Following a report conducted by the EPA that demonstrated this type of container contributed high levels of PFAS to a pesticide, this research demonstrates the first measurement of the ability of PFAS to leach from the containers into food as well as the effect of temperature on the leaching process.

Results also showed the PFAS were capable of migrating from the fluorinated containers into food, resulting in a direct route of significant exposure to the hazardous chemicals, which have been linked to several health issues including prostate, kidney and testicular cancers, low birth weight, immunotoxicity and thyroid disease.

“Not only did we measure significant concentrations of PFAS in these containers, we can estimate the PFAS that were leaching off creating a direct path of exposure,” said Graham Peaslee, professor of physics in the Department of Physics and Astronomy at Notre Dame and an author of the study.

Boeing Successfully Demonstrates Anti-Jam Capability for U.S. Department of Defense Satellites

U.S. Air Force Capt. Yousuke Matsui from the U.S. Space Force’s Space Systems Command and several members of Boeing’s PTES team work with the key management system initialization interface during the operational capability demonstration at the Joint SATCOM Engineering Center at Aberdeen Proving Ground.
Photo Credit: James K. Lee

Boeing engineers successfully demonstrated the company’s Protected Enterprise Tactical Service (PTES) over an on-orbit operational satellite, validating the design for the U.S. Space Force’s ground-based anti-jamming satellite communications (SATCOM) capability. The demonstration was the first time the PTES program integrated all of the end-to-end capabilities and tested them over the air using a commercial satellite.

The event, which took place at the Joint Satellite Engineering Center, closely represented scenarios of users accessing field-deployed equipment via a Protected Tactical Waveform (PTW) user terminal interface. The demonstration validated integration of software and hardware with the current U.S. Department of Defense (DoD) SATCOM architecture and exercised PTW anti-jam capability. Actual initial deployment of this capability for operational use will be over the government’s Wideband Global SATCOM (WGS) fleet, taking advantage of its military features for high levels of jamming resistance and connectivity assurance.

Pioneering study shows flood risks can still be considerably reduced if all global promises to cut carbon emissions are kept

Maps show historical expected annual flood damage (EAD) in GBP billion at 2020 values, and calculated EAD percentage increase with 1.8 degrees global warming.
Illustration Credit: University of Bristol and Fathom

Annual damage caused by flooding in the UK could increase by more than a fifth over the next century due to climate change unless all international pledges to reduce carbon emissions are met, according to new research.

The study, led by the University of Bristol and global water risk modelling leader Fathom, reveals the first-ever dataset to assess flood hazard using the most recent Met Office climate projections which factor in the likely impact of climate change.

Its findings show the forecasted annual increase in national direct flood losses, defined as physical damage to property and businesses, due to climate change in the UK can be kept below 5% above recent historical levels. But this is only on the proviso that all countries fulfil the ambitious pledges they signed up to at COP26 and also that countries, including the UK, which made further Net Zero commitments, actually achieve these on time and in full.

Small size of bioprosthetic aortic valves less dangerous than previously believed

Michael Dismorr
Photo Credit: Oliver von Olnhausen

Researchers at the Thoracic Surgery research group, the Department of Molecular Medicine and Surgery, have performed a nation-wide study of patients who underwent bioprosthetic aortic valve replacement in Sweden between 2003 and 2018. The study is published in the Journal of the American College of Cardiology, JACC, and shows that it is less dangerous than previously believed to receive a small bioprosthetic aortic valve in relation to the patient's size.

During surgical aortic valve replacement, the patient receives a valve prosthesis that matches the size of the aortic root. Sometimes, that size is too small in relation to the patient’s body size. This puts strain on the heart to pump enough blood that the body needs through a narrow valve. The level of “narrowness” is measured as Prosthesis Patient Mismatch, PPM.

“Prior studies have shown that both moderate and severe PPM decreases survival and increases the risk for heart failure. In our study, we can confirm that severe PPM decreases survival and increases the risk for heart failure, while moderate PPM has a very limited effect on survival and no effect on the risk for heart failure”, says Michael Dismorr, postdoctoral researcher at the Department of Molecular Medicine and Surgery and first author of the study.

How Do Microbes Live Off Light?

Prof. Oded Béjà (left) and PhD student Ariel Chazan
Photo Credit: Technion-Israel Institute of Technology

Plants convert light into a form of energy that they can use – a molecule called adenosine triphosphate (ATP) – through photosynthesis. This is a complex process that also produces sugar, which the plant can use for energy later, and oxygen. Some bacteria that live in the light-exposed layers of water sources can also convert light to ATP, but the process they use is simpler and less efficient than photosynthesis. Nonetheless, Technion – Israel Institute of Technology researchers now find this process isn’t as straightforward and limited as was previously thought.

Rhodopsin are the light-driven proton pumps that bacteria employ to produce ATP. Whereas photosynthesis is a process that involves multiple stages and proteins, rhodopsin performs everything itself. It is not more efficient, but rather it is like the difference between a medieval workshop and a modern factory. The rhodopsin's are activated by a molecule called “retinal,” which absorbs light. Specifically, in these proteins retinal absorbs green light. A different molecule, a carotenoid “antenna,” can enable it to also absorb blue light as well, increasing the amount of energy the rhodopsin can produce.

New Fluorescent Sensors Make it Possible to Detect the Concentration of Mercury in Water

New fluorophores selectively and with high sensitivity recognize mercury ions.
Photo Credit: Anna Marinovich

Scientists from the UrFU, together with Italian and Bulgarian colleagues, synthesized new heterocyclic fluorophores - four types of carboxamides of 2-aryl-1,2,3-triazoles. Their photophysical properties have been investigated under different conditions - solvents and their binary mixtures with water. Sensors based on the fluorophores obtained were sensitive to mercury, so they can be used to detect mercury concentrations in water. Further research will focus on determining the possibility of using these fluorophores to target medicines to affected organs. The authors have published an article on their research and results in the journal Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy.

"A disadvantage of organic fluorophores is their poor solubility in water and aqueous environments. At the same time, when water is added to organic solvents, most dyes and fluorophores have fluorescence quenching. However, in 2001, Professor Ben Zhong Tan of the Chinese University of Hong Kong found that some fluorophores observed not quenching, but rather an increase the fluorescence intensity. This is due to the formation of much larger particles, or nano-aggregates, from the molecules of fluorophores. Tan's discovery was of great significance. Much scientific effort has been devoted to studying the mechanism of his discovery, as well as to the design and synthesis of new fluorophores with the effect of increasing the emission. The fluorophores we obtained have also demonstrated in a mixture of organic solvent and water the effect described by Tang, and with a particular intensity. This opens the way to the practical application of the obtained fluorophores in various fields, especially in the aquatic environment," says Natalya Belskaya, Full Professor of the UrFU Department of Technology of Organic Synthesis and leader of the research team.

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