Intermittent fasting is safe, effective for those with Type 2 diabetes, study suggests

Time-restricted eating, also known as intermittent fasting, can help people with Type 2 diabetes lose weight and control their blood sugar levels, according to a new study published in JAMA Network Open from researchers at the University of Illinois Chicago.

Participants who ate only during an eight-hour window between noon and 8 p.m. each day actually lost more weight over six months than participants who were instructed to reduce their calorie intake by 25%. Both groups had similar reductions in long-term blood sugar levels, as measured by a test of hemoglobin A1C, which shows blood sugar levels over the past three months.

The study was conducted at UIC and enrolled 75 participants into three groups: those who followed the time-restricted eating rules, those who reduced calories and a control group. Participants’ weight, waist circumference, blood sugar levels and other health indicators were measured over the course of six months.

Senior author Krista Varady said that participants in the time-restricted eating group had an easier time following the regime than those in the calorie-reducing group. The researchers believe this is partly because patients with diabetes are generally told to cut back on calories by their doctors as a first line of defense, so many of these participants likely had already tried — and struggled with — that form of dieting. And while the participants in the time-restricted eating group were not instructed to reduce their calorie intake, they ended up doing so by eating within a fixed window.

“Our study shows that time-restricted eating might be an effective alternative to traditional dieting for people who can’t do the traditional diet or are burned out on it,” said Varady, a professor of kinesiology and nutrition. “For many people trying to lose weight, counting time is easier than counting calories.”

There were no serious adverse events reported during the six-month study. Occurrences of hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar) did not differ between the diet groups and control groups.

Today, 1 in 10 U.S. residents has diabetes, and that number is expected to rise to 1 in 3 by 2050 if current trends continue, the researchers explain. Finding more options for controlling weight and blood sugar levels for these patients, therefore, is crucial.

Just over half the participants in the study were Black and another 40% were Hispanic. This is notable as diabetes is particularly prevalent among those groups, so having studies that document the success of time-restricted eating for them is particularly useful, the researchers said.

The study was small and should be followed up by larger ones, said Varady, who is also a member of the University of Illinois Cancer Center. While it acts as a proof of concept to show that time-restricted eating is safe for those with Type 2 diabetes, Varady said people with diabetes should consult their doctors before starting this sort of diet.

The other current and former UIC authors on the paper are Vasiliki Pavlou, Sofia Cienfuegos, Shuhao Lin, Mark Ezpeleta, Kathleen Ready, Sarah Corapi, Jackie Wu, Jason Lopez, Kelsey Gabel, Lisa Tussing-Humphreys, Vanessa Oddo, Julienne Sanchez and Dr. Terry Unterman. Other authors are from Northwestern University, the University of Minnesota, Minneapolis, and the University of Southern California.

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Possible cause of male infertility

Mature spermatozoa are characterized by an head, midpiece and a long tail for locomotion. Now, researchers from the University Hospital Bonn (UKB) and the Transdisciplinary Research Unit “Life & Health” at the University of Bonn have found that a loss of the structural protein ACTL7B blocks spermatogenesis in male mice. The cells can no longer develop their characteristic shape and remain in a rather round form. The animals are infertile. The results of the study have now been published in the scientific journal Development.

Male sperm cells are constantly produced in large quantities in the testicles during so-called spermatogenesis. In this process, the typical elongated sperm cells are formed from round germ cells. This enormous change in shape requires the fine tuned reorganization of specialized structural proteins. One of these structural proteins is ACTL7B. “Since it is exclusively made in humans and mice during the maturation of male sperm, it has been postulated that the protein is important for this phase of development,” notes corresponding author Prof. Hubert Schorle from the Institute of Pathology at UKB, who is also a member of the Transdisciplinary Research Area (TRA) “Life & Health” at the University of Bonn.

To investigate the role of the structural protein in spermiogenesis, Prof. Schorle’s team generated a mouse model with a mutation in the Actl7b gene using gene-editing technology. This results in a complete loss of function of ACTL7B. “Without ACTL7B, development is blocked, the cells often remain in a roundish shape, usually do not form the elongated, typical sperm shape and die to a large extent ,” says first author Gina Esther Merges, a doctoral student in Professor Schorle’s laboratory.

Disruption in the network of proteins

In this context, the Bonn researchers found that ACTL7B is required for the reorganization of the cytoskeleton of spermatids. Using mass spectrometric analyses, they identified two interaction partners of ACTL7B, DYNLL1 and DYNLL2. “We were able to show that without the structural protein, DYNLL1 and 2 are not correctly localized in the round spermatids. Since it is probably a larger protein complex with further interaction partners, we attribute the above described effect to a loss of temporally and spatially precisely regulated and targeted redistribution of these proteins,” Prof. Schorle notes.

This explains why the sperm of male mice with a mutated Actl7b gene is not able to develop the characteristic shape. Due to this, the animals are infertile. In addition, according to other research, there is evidence that levels of the protein ACTL7B are reduced in some fertility patients. “Our study shows that mutations in the Actl7b gene could be the cause of male infertility,” says Prof. Schorle.

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New battery technology could lead to safer, high-energy electric vehicles

University of Maryland researchers studying how lithium batteries fail have developed a new technology that could enable next-generation electric vehicles (EVs) and other devices that are less prone to battery fires while increasing energy storage.

The innovative method, presented in a paper published Wednesday in the journal Nature, suppresses the growth of lithium dendrites — damaging branch-like structures that develop inside so-called all-solid-state lithium batteries, preventing firms from broadly commercializing the promising technology. But this new design for a battery “interlayer,” led by Department of Chemical and Biomolecular Engineering Professor Chunsheng Wang, stops dendrite formation, and could open the door for production of viable all-solid-state batteries for EVs.

At least 750,000 registered EVs in the U.S. run on lithium-ion batteries — popular because of their high energy storage but containing a flammable liquid electrolyte component that burns when overheated. While no government agency tracks vehicle fires by type of car, and electric car battery fires appear to be relatively rare, they pose particular risks; the National Transportation Safety Board reports that first responders are vulnerable to safety risks, including electric shock and the exposure to toxic gasses emanating from damaged or burning batteries.

All-solid-state batteries could lead to cars that are safer than current electric or internal combustion models, but creating a strategy to bypass the drawbacks was laborious, Wang said. When these batteries are operated at the high capacities and charging-discharging rates that electric vehicles demand, lithium dendrites grow toward the cathode side, causing short circuits and a decay in capacity.

He and Postdoctoral Associate Hongli Wan began to develop a theory for the formation of lithium dendrite growth in 2021; it remains a matter of scientific debate, the researchers said.

“After we figured out that part, we proposed the idea to redesign the interlayers that would effectively suppress the lithium dendrite growth,” he said.

Their solution is unique because of the stabilizing of the battery’s interfaces between the solid electrolyte and the anode (where electrons from a circuit enter the battery) and the electrolyte and the cathode (where energy flows out of the battery). The new battery structure adds a fluorine-rich interlayer that stabilizes the cathode side, as well as a modification of the anode’s interlayer with magnesium and bismuth — suppressing the lithium dendrite.

“Solid-state batteries are next-generation because they can achieve high energy and safety. In current batteries, if you achieve high energy, you’ll sacrifice safety,” said Wang.

Researchers have other challenges to solve before the product enters the market. To commercialize all-solid-state batteries, experts will have to scale down the solid electrolyte layer to achieve a similar thickness to the lithium-ion batteries’ electrolyte, which will improve energy density — or how much power the battery can store. High costs of basic materials are another challenge, the team said.

Aiming to release the new batteries to the market by 2026, advanced battery manufacturer Solid Power plans to begin trials of the new technology to assess its potential for commercialization. Continuing research aims to further boost energy density, the researchers said.

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Meltwater flowing beneath Antarctic glaciers may be accelerating their retreat

A new Antarctic ice sheet modeling study from scientists at UC San Diego’s Scripps Institution of Oceanography suggests that meltwater flowing out to sea from beneath Antarctic glaciers is making them lose ice faster.

The model’s simulations suggest this effect is large enough to make a meaningful contribution to global sea-level rise under high greenhouse gas emissions scenarios.

The extra ice loss caused by this meltwater flowing out to sea from beneath Antarctic glaciers is not currently accounted for in the models generating major sea-level rise projections, such as those of the Intergovernmental Panel on Climate Change (IPCC). If this process turns out to be an important driver of ice loss across the entire Antarctic ice sheet, it could mean current projections underestimate the pace of global sea-level rise in decades to come.

“Knowing when and how much global sea-level will rise is critical to the welfare of coastal communities,” said Tyler Pelle, the study’s lead author and a postdoctoral researcher at Scripps. “Millions of people live in low-lying coastal zones and we can’t adequately prepare our communities without accurate sea-level rise projections.”

The study, published October 27 in Science Advances and funded by the National Science Foundation (NSF), NASA, and the Cecil H. and the Ida M. Green Foundation for Earth Sciences at the Institute of Geophysics and Planetary Physics at Scripps, modeled the retreat of two glaciers in East Antarctica through the year 2300 under different emissions scenarios and projected their contributions to sea-level rise. Unlike previous Antarctic ice sheet models, this one included the influence of this flow of meltwater from beneath glaciers out to sea, which is known as subglacial discharge.

The two glaciers the study focused on, named Denman and Scott, together hold enough ice to cause nearly 1.5 meters (5 feet) of sea-level rise. In a high emissions scenario (IPCC’s SSP5-8.5 scenario, which assumes no new climate policy and features 20% higher CO2 emissions by 2100), the model found that subglacial discharge increased the sea-level rise contribution of these glaciers by 15.7%, from 19 millimeters (0.74 inches) to 22 millimeters (0.86 inches) by the year 2300.

These glaciers, which are right next to each other, sit atop a continental trench that is more than two miles deep; once their retreat reaches the trench’s steep slope, their contribution to sea-level rise is expected to accelerate dramatically. With the added influence of subglacial discharge, the model found that the glaciers retreated past this threshold about 25 years earlier than they did without it.

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“I think this paper is a wake up call for the modeling community. It shows you can’t accurately model these systems without taking this process into account,” said Jamin Greenbaum, co-author of the study and a researcher at Scripps’ Institute of Geophysics and Planetary Physics.

A key takeaway, beyond the understudied role of subglacial discharge in accelerating sea-level rise, is the importance of what humanity does in the coming decades to rein in greenhouse gas emissions, said Greenbaum. The low emissions scenario runs of the model did not show the glaciers retreating all the way into the trench and avoided the resulting runaway contributions to sea-level rise.

“If there is a doomsday story here it isn’t subglacial discharge,” said Greenbaum. “The real doomsday story is still emissions and humanity is still the one with its finger on the button.”

In Antarctica, subglacial meltwater is generated from melting that occurs where the ice sits on continental bedrock. The main sources of the heat melting the ice in contact with the ground are friction from the ice grinding across the bedrock and geothermal heat from Earth’s interior permeating up through the crust.

Prior research suggested that subglacial meltwater is a common feature of glaciers around the world and that it is present under several other massive Antarctic glaciers, including the infamous Thwaites Glacier in West Antarctica.

When subglacial discharge flows out to sea it is thought to accelerate melting of the glacier’s ice shelf — a long floating tongue of ice that extends out to sea beyond the last part of the glacier that is still in contact with solid ground (known as the grounding line). Subglacial discharge is thought to speed up ice shelf melting and glacial retreat by causing ocean mixing that stirs in additional ocean heat within the cavity beneath a glacier’s floating ice shelf. This enhanced ice shelf melting then causes the upstream glacier to accelerate, which can drive sea level rise.

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The notion that subglacial discharge causes additional ice shelf melting is widely accepted in the scientific community, said Greenbaum. But it hasn’t been included in sea-level rise projections because many researchers weren’t sure if the process’ effect was sufficiently large to increase sea-level rise, mainly because its effects are localized around the glacier’s ice shelf.

Pelle said subglacial discharge came onto his radar in 2021 when he and his colleagues observed that East Antarctica’s Denman Glacier’s ice shelf was melting faster than expected given local ocean temperatures. Puzzlingly, Denman’s neighbor Scott Glacier’s ice shelf was melting much more slowly despite virtually identical ocean conditions.

To test whether subglacial discharge could reconcile the melt rates seen at the Denman and Scott ice shelves, as well as whether subglacial meltwater might accelerate sea-level rise, the team combined models for three different environments: the ice sheet, the space between the ice sheet and bedrock, and the ocean.

Once the researchers married the three models into one they ran a series of projections up to 2300 using a NASA supercomputer.

The projections featured three main scenarios: a control that featured no additional ocean warming, a low emissions pathway (SSP1-2.6), and a high emissions pathway (SSP5-8.5). For each scenario, the researchers created projections with and without the effect of present-day levels of subglacial discharge.

The model’s simulations revealed that adding in subglacial discharge reconciled the melt rates seen at Denman and Scott Glaciers. As for why Scott Glacier was melting so much slower than Denman, Pelle said the model showed that “a strong subglacial discharge channel drained across the Denman Glacier grounding line, while a weaker discharge channel drained across the Scott Glacier grounding line.” The strength of the discharge channel at Denman, Pelle explained, was behind its speedy melt.

For the control and low-emissions model runs the contributions to sea-level rise were close to zero or even slightly negative with or without subglacial discharge at 2300. But in a high emissions scenario, the model found that subglacial discharge increased the sea-level rise contribution of these glaciers from 19 millimeters (0.74 inches) to 22 millimeters (0.86 inches) in 2300.

In the high emissions scenario that included subglacial discharge, Denman and Scott Glaciers retreated into the two-mile-deep trench beneath them by 2240, about 25 years earlier than they did in the model runs without subglacial discharge. Once the grounding lines of the Denman and Scott Glaciers retreat past the lip of this trench their yearly sea-level rise contribution explodes, reaching a peak of 0.33 millimeters (0.01 inches) per year — roughly half of the present-day annual sea-level rise contribution of the entire Antarctic ice sheet.

Pelle said the trench’s steep slope is behind this explosive increase in sea-level rise contribution. As the glacier retreats down slope, its ice shelf begins losing thicker and thicker slabs of ice from its leading edge. This process of ice loss quickly outpaces ice accumulation at the ice sheet’s interior, causing further glacial retreat. Researchers refer to this process as “Marine Ice Sheet Instability,” and it can promote explosive ice loss from glaciers like Denman and Scott.

Researchers refer to topography such as the trench beneath Denman and Scott Glaciers as a retrograde slope and worry that it creates a positive feedback loop by which glacial retreat begets more retreat. Large areas of the West Antarctic Ice Sheet, such as Thwaites Glacier, also have retrograde slopes that, while not as dramatic as the Denman-Scott trench, contribute to fears of broader ice sheet instability.

“Subglacial meltwater has been inferred beneath most if not all Antarctic glaciers, including Thwaites, Pine Island, and Totten glaciers,” said Pelle. “All these glaciers are retreating and contributing to sea-level rise and we are showing that subglacial discharge could be accelerating their retreat. It’s urgent that we model these other glaciers so we can get a handle on the magnitude of the effect subglacial discharge is having.”

The researchers behind this study are doing just that. Pelle said they are in the process of submitting a research proposal to extend their new model to the entire Antarctic ice sheet.

Future iterations of the model may also attempt to couple the subglacial environment with the ice sheet and ocean models so that the amount of subglacial meltwater dynamically responds to these other factors. Greenbaum said that the current version of their model kept the amount of subglacial meltwater constant throughout the model runs, and that making it respond dynamically to the surrounding environment would likely make the model more true to life.

“This also means that our results are probably a conservative estimate of the effect of subglacial discharge,” said Greenbaum. “That said, we can’t yet say how much sea-level rise will be accelerated by this process — hopefully it’s not too much.”

Part of Greenbaum’s upcoming fieldwork in Antarctica, supported by NSF and NASA, aims to directly investigate the impacts of subglacial meltwater in both the East and West Antarctic ice sheets. In collaboration with the Australian Antarctic Division and the Korea Polar Research Institute, Greenbaum and his collaborators will be visiting the ice shelves of Denman and Thwaites Glaciers in East and West Antarctica, respectively, looking for direct evidence that subglacial freshwater is discharging into the ocean beneath the glaciers’ ice shelves and contributing to warming.

In addition to Pelle and Greenbaum, the study was co-authored by Christine Dow of the University of Waterloo, Adrian Jenkins of Northumbria University, and Mathieu Morlighem of Dartmouth College.

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HRT: Sharp rise in prescriptions after menopause campaign

Celebrities like Davina McCall have raised awareness of women’s symptoms when their periods stop.

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Conjoined twins meet at London hospital that treated them

The six sets of siblings were all treated at Great Ormond Street Hospital in London.

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Motor neurone disease: Sufferers describe wait to get diagnosed

Two MND sufferers tell the BBC how the debilitating neurological condition is hard to diagnose.

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Conjoined twins: Defying the odds to survive

They were not expected to survive but Ruby and Rosie, now 11, are celebrating with five other sets.

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NHS waits could exceed eight million by summer, charity says

Based on latest trends, yet more patients will be forced to wait, even if doctor strikes cease, projections suggest.

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Youngest children in class with ADHD as likely to keep diagnosis in adulthood as older pupils, find scientists

Children who are the youngest in their class to be identified with ADHD are just as likely to keep the diagnosis as older pupils in their year group, scientists have found.

Experts from the University of Southampton and Paris Nanterre University, working with researchers worldwide, made the discovery after examining data from thousands of patients with attention deficit hyperactivity disorder.

In the past, scientists have questioned the validity of an ADHD diagnosis in younger pupils — arguing they receive it because they are less mature than those born towards the start of the school year.

But the study, published in Lancet Psychiatry, revealed children who are the youngest in the class and get diagnosed with the condition were still as likely to retain it later on as their older peers.

Senior lead author Professor Samuele Cortese, a child and adolescent psychiatrist at the University of Southampton, said: “We know the youngest children in their year group are more likely to be diagnosed with ADHD — but many believe this is because they lag behind their older classmates.

“However, no one has ever explored if these younger children who are diagnosed with ADHD retain the diagnosis later on — until now. Our study shows for the first time that these youngsters are no more likely to lose the diagnosis over time than older children.”

Around 360 million people worldwide have been diagnosed with ADHD, according to the World Health Organisation, with around a third under the age of 18.

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Symptoms include impulsiveness, disorganisation, poor time management skills, difficulty focusing and restlessness.

The study by Southampton and Paris Nanterre, undertaken with 161 scientists worldwide, was based on the largest data set ever created to explore the effect of month of birth on the persistence of ADHD.

In total, it examined data from more than 6,500 patients globally who have been followed up for a period between the ages of four and 33 years old.

Dr Corentin Gosling, an associate professor from the University Paris Nanterre in France and visiting researcher at Southampton, was the first author on the study.

He said: “Our work shows the diagnosis of ADHD in children with a young relative age is not especially unstable.

“However, it could not assess whether it is an appropriate diagnosis or it is because, once a child receives the ADHD label, parents and teachers consider the child as having ADHD and are influenced by the diagnosis. Future studies should solve this question.”

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