Toxic chemicals from microplastics can be absorbed through skin

Toxic chemicals used to flame-proof plastic materials can be absorbed into the body through skin, via contact with microplastics, new research shows.

The study offers the first experimental evidence that chemicals present as additives in microplastics can leach into human sweat, and then be absorbed through the skin, into the bloodstream.

Many chemicals used as flame retardants and plasticisers have already been banned, due to evidence of adverse health effects including damage to the liver or nervous system, cancer, and risks to reproductive health. However, these chemicals are still present in the environment in older electronics, furniture, carpets, and building materials.

While the harm caused by microplastics is not fully understood, there is increasing concern over their role as conduits of human exposure to toxic chemicals.

The research team demonstrated in a study published last year, that chemicals were leached from microplastics into human sweat. The current study now shows that those chemicals can also be absorbed from sweat across the skin barrier into the body.

In their experiments, the team used innovative 3D human skin models as alternatives to laboratory animals and excised human tissues. The models were exposed over a 24-hour period to two common forms of microplastics containing polybrominated diphenyl ethers (PBDEs), a chemical group commonly used to flame retard plastics.

The results, published in Environment International, showed that as much as 8% of the chemical exposed could be taken up by the skin, with more hydrated — or ‘sweatier’ — skin absorbing higher levels of chemical. The study provides the first experimental evidence into how this process contributes to levels of toxic chemicals found in the body.

Dr Ovokeroye Abafe, now at Brunel University, carried out the research while at the University of Birmingham. He said: “Microplastics are everywhere in the environment and yet we still know relatively little about the health problems that they can cause. Our research shows that they play a role as ‘carriers’ of harmful chemicals, which can get into our bloodstream through the skin. These chemicals are persistent, so with continuous or regular exposure to them, there will be a gradual accumulation to the point where they start to cause harm.”

Dr Mohamed Abdallah, Associate Professor of Environmental Sciences at the University of Birmingham, and principal investigator for the project, said: “These findings provide important evidence for regulators and policymakers to improve legislation around microplastics and safeguard public health against harmful exposure.”

Professor Stuart Harrad, co-author of the paper, added “the study provides an important step forward in understanding the risks of exposure to microplastics on our health. Building on our results, more research is required to fully understand the different pathways of human exposure to microplastics and how to mitigate the risk from such exposure.”

In future research, the team plan to investigate other routes through which microplastics could be responsible for toxic chemicals entering the body, including inhalation and ingestion. The work is funded by a Marie Curie Research Fellowship, within the European Union’s Horizon 2020 Research and Innovation Programme.

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Warming of Antarctic deep-sea waters contribute to sea level rise in North Atlantic, study finds

Analysis of mooring observations and hydrographic data suggest the Atlantic Meridional Overturning Circulation deep water limb in the North Atlantic has weakened. Two decades of continual observations provide a greater understanding of the Earth’s climate regulating system.

A new study published in the journal Nature Geoscience led by scientists at University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science, and the National Oceanic and Atmospheric Administration’s Atlantic Oceanographic and Meteorological Laboratory, found that human-induced environmental changes around Antarctica are contributing to sea level rise in the North Atlantic.

The research team analyzed two decades of deep sea oceanographic data collected by observational mooring programs to show that a critical piece of Earth’s global system of ocean currents in the North Atlantic has weakened by about 12 percent over the past two decades.

“Although these regions are tens of thousands of miles away from each other and abyssal areas are a few miles below the ocean surface, our results reinforce the notion that even the most remote areas of the world’s oceans are not untouched by human activity,” said the study’s lead author Tiago Biló, an assistant scientist at the Rosenstiel School’s NOAA Cooperative Institute for Marine and Atmospheric Studies.

As part of the NOAA-funded project DeepT (Innovative analysis of deep and abyssal temperatures from bottom-moored instrument), the scientists analyzed data from several observational programs to study changes over time in a cold, dense, and deep water mass located at depths greater than 4,000 meters (2.5 miles) below the ocean surface that flow from the Southern Ocean northward and eventually upwells to shallower depths in other parts of the global ocean such as the North Atlantic.

This shrinking deep-ocean branch — that scientists call the abyssal limb — is part of the Atlantic Meridional Overturning Circulation (AMOC), a three-dimensional system of ocean currents that act as a “conveyer belt” to distribute heat, nutrients, and carbon dioxide across the world’s oceans.

This near-bottom branch is comprised of Antarctic bottom water, which forms from the cooling of seawater in the Southern Ocean around Antarctica during winter months. Among the different formation mechanisms of this bottom water, perhaps the most important is the so-called brine rejection, a process that occurs when salty water freezes. As sea ice forms, it releases salt into the surrounding water, increasing its density. This dense water sinks to the ocean floor, creating a cold, dense water layer that spreads northward to fill all three ocean basins — the Indian, Pacific, and Atlantic oceans. During the 21st century, the researchers observed that the flow of this Antarctic layer across 16°N latitude in the Atlantic had slowed down, reducing the inflow of cold waters to higher latitudes, and leading to warming of waters in the deep ocean.

“The areas affected by this warming spans thousands of miles in the north-south and east-west directions between 4,000- and 6,000-meters of depth,” said William Johns, a co-author and professor of ocean sciences at the Rosenstiel School. “As a result, there is a significant increase in the abyssal ocean heat content, contributing to local sea level rise due to the thermal expansion of the water.”

“Our observational analysis matches what the numerical models have predicted — human activity could potentially impose circulation changes on the entire ocean,” said Biló. “This analysis was only possible because of the decades of collective planning and efforts by multiple oceanographic institutions worldwide.”

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Ketamine addict: ‘I can’t walk 50m without weeing’

Specialist clinics are helping increasing numbers of young ketamine users with damaged bladders.

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Almost a quarter of kids aged 5-7 have smartphones

The regulator calls the data a “wake up call”, and says parents and industry need to do more.

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Scotland’s under-18s gender clinic pauses puberty blockers

It follows a landmark review of gender services in England which warned of a lack of research.

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Children used as ‘guinea pigs’ in clinical trials

They were given infected blood products in trials without their knowledge, the BBC has found.

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Octopus inspires new suction mechanism for robots

A new robotic suction cup which can grasp rough, curved and heavy stone, has been developed by scientists at the University of Bristol.

The team, based at Bristol Robotics Laboratory, studied the structures of octopus biological suckers, which have superb adaptive suction abilities enabling them to anchor to rock.

In their findings, published in the journal PNAS today, the researchers show how they were able create a multi-layer soft structure and an artificial fluidic system to mimic the musculature and mucus structures of biological suckers.

Suction is a highly evolved biological adhesion strategy for soft-body organisms to achieve strong grasping on various objects. Biological suckers can adaptively attach to dry complex surfaces such as rocks and shells, which are extremely challenging for current artificial suction cups. Although the adaptive suction of biological suckers is believed to be the result of their soft body’s mechanical deformation, some studies imply that in-sucker mucus secretion may be another critical factor in helping attach to complex surfaces, thanks to its high viscosity.

Lead author Tianqi Yue explained: “The most important development is that we successfully demonstrated the effectiveness of the combination of mechanical conformation — the use of soft materials to conform to surface shape, and liquid seal — the spread of water onto the contacting surface for improving the suction adaptability on complex surfaces. This may also be the secret behind biological organisms ability to achieve adaptive suction.”

Their multi-scale suction mechanism is an organic combination of mechanical conformation and regulated water seal. Multi-layer soft materials first generate a rough mechanical conformation to the substrate, reducing leaking apertures to just micrometres. The remaining micron-sized apertures are then sealed by regulated water secretion from an artificial fluidic system based on the physical model, thereby the suction cup achieves long suction longevity on diverse surfaces but with minimal overflow.

Tianqi added: “We believe the presented multi-scale adaptive suction mechanism is a powerful new adaptive suction strategy which may be instrumental in the development of versatile soft adhesion.

“Current industrial solutions use always-on air pumps to actively generate the suction however, these are noisy and waste energy.

“With no need for a pump, it is well known that many natural organisms with suckers, including octopuses, some fishes such as suckerfish and remoras, leeches, gastropods and echinoderms, can maintain their superb adaptive suction on complex surfaces by exploiting their soft body structures.”

The findings have great potential for industrial applications, such as providing a next-generation robotic gripper for grasping a variety of irregular objects.

The team now plan to build a more intelligent suction cup, by embedding sensors into the suction cup to regulate suction cup’s behaviour.

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Siblings with unique genetic change help scientists progress drug search for type 1 diabetes

Two siblings who have the only known mutations in a key gene anywhere in the world have helped scientists gain new insights that could help progress the search for new treatments in type 1 diabetes.

Type 1 diabetes (also known as autoimmune diabetes) is a devastating and life-long disease, in which the patient’s immune cells wrongly destroy the insulin producing beta cells in the pancreas. People living with autoimmune diabetes need to test their blood sugar and inject insulin throughout their lives to control their blood sugars and prevent complications.

Autoimmune diabetes with clinical onset in very early childhood is rare and can result from a variety of genetic variants. However, there are many cases of early onset diabetes without known genetic explanation. In addition, some cancer patients treated with a category of immunotherapy known as immune checkpoint inhibitors — which target the same pathway that the mutation was found in — are prone to developing autoimmune diabetes. The reason why only this category of cancer immunotherapy can trigger autoimmune diabetes is not well understood. Like type 1 diabetes, genetic or immunotherapy-associated autoimmune diabetes requires life-long insulin replacement therapy — there is currently no cure.

The new research, published in the Journal of Experimental Medicine, began when researchers studied two siblings who were diagnosed with a rare genetic form of autoimmune diabetes in the first weeks of life. The University of Exeter offers free genetic testing worldwide for babies diagnosed with diabetes before they are nine months old. For most of these babies, this service provides a genetic diagnosis and in around half of these babies, it allows for a change in treatment.

When researchers tested the two siblings in the study, no mutation in any of the known causes was identified. The Exeter team then performed whole genome sequencing to look for previously unknown causes of autoimmune diabetes. Through this sequencing, they found a mutation in the gene encoding PD-L1 in the siblings and realised it could be responsible for their very-early-onset autoimmune diabetes.

Study authorDr Matthew Johnson, from the University of Exeter, UK, said: “PD-L1 has been particularly well studied in animal models because of its crucial function in sending a stop signal to the immune system and its relevance to cancer immunotherapy. But, to our knowledge, nobody has ever found humans with a disease-causing mutation in the gene encoding PD-L1. We searched the globe, looking at all the large-scale datasets that we know of, and we haven’t been able to find another family. These siblings therefore provide us with a unique and incredibly important opportunity to investigate what happens when this gene is disabled in humans.”

The PD-L1 protein is expressed on many different cell types. Its receptor, PD-1, is expressed exclusively on immune cells. When the two proteins bind together it provides a stop signal to the immune system, preventing collateral damage to the bodies tissues and organs.

Researchers from the Rockefeller Institute in New York and King’s College London joined forces with Exeter to study the siblings, with funding from Wellcome, The Leona M. and Harry B. Helmsley Charitable Trust, Diabetes UK, and the US National Institutes for Health. After contacting the family’s clinician in Morocco, the Exeter team visited the siblings where they were living to collect samples and return them to King’s College London, within the crucial ten-hour window for analysis while the immune cells were still alive. The London and New York teams then performed extensive analysis on the siblings’ cells.

Study co-author Dr Masato Ogishi, from the Rockefeller University in New York, said: “We first showed that the mutation completely disabled the function of PD-L1 protein. We then studied the immune system of the siblings to look for immunological abnormalities that could account for their extremely early-onset diabetes. As we previously described another two siblings with PD-1 deficiency, both of whom had multi-organ autoimmunity including autoimmune diabetes and extensive dysregulation in their immune cells, we expected to find severe dysregulation of the immune system in the PD-L1-deficient siblings. To our great surprise, their immune systems looked pretty much normal in almost all aspects throughout the study. Therefore, PD-L1 is certainly indispensable for preventing autoimmune diabetes but is dispensable for many other aspects of human immune system. We think that PD-L2, another ligand of PD-1, albeit less well-studied than PD-L1, may be serving as a back-up system when PD-L1 is not available. This concept needs to be further investigated in the context of artificial blockade for PD-L1 as cancer immunotherapy.”

Study co-author Professor Timothy Tree, from King’s College London, said: “Through studying this one set of siblings — unique in the world to our knowledge — we have found that the PD-L1 gene is essential for avoiding autoimmune diabetes, but is not essential for ‘everyday’ immune function. This leads us to the grand question; ‘what is the role of PD-L1 in our pancreas making it critical for preventing our immune cells destroying our beta cells?’ We know that under certain conditions beta cells express PD-L1. However, certain types of immune cells in the pancreas also express PD-L1. We now need to work out the “communication” between different cell types that is critical for preventing autoimmune diabetes.

“This finding increases our knowledge of how autoimmune forms of diabetes such as type 1 diabetes develop. It opens up a new potential target for treatments that could prevent diabetes in the future. Simultaneously, it gives new knowledge to the cancer immunotherapy field by uniquely providing the results of completely disabling PD-L1 in a person, something you could never manipulate in studies. Reducing PD-L1 is already effective for cancer treatment, and boosting it is now being investigated as a type 1 diabetes treatment — our findings will help accelerate the search for new and better drugs.”

Dr Lucy Chambers, Head of Research Communications at Diabetes UK, said: “Pioneering treatments that alter the behaviour of the immune system to hold off its attack on the pancreas are already advancing type 1 diabetes treatment in the USA, and are awaiting approval here in the UK.

“By zeroing in on the precise role of an important player in the type 1 diabetes immune attack, this exciting discovery could pave the way for treatments that are more effective, more targeted and more transformational for people with or at risk of type 1 diabetes.”

Helmsley Program Officer Ben Williams said: “New drugs often fail in development because scientific discoveries made in animal models don’t translate into humans. As such, drug developers strongly prefer to pursue new drugs where human genetic evidence supports the drug’s target. This study provides such compelling evidence that PD-L1 is a high-priority target to treat T1D, and should be pursued with the ambition of eventually reducing the burden of this difficult to manage disease.”

The paper is entitled ‘Human inherited PD-L1 deficiency is clinically and immunologically less severe than PD-1 deficiency’ and is published in the Journal of Experimental Medicine. The research was supported by the National Institute of Health and Care Research (NIHR) Exeter Biomedical Research Centre and The NIHR Exeter Clinical Research Facility.

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New urine-based test detects high-grade prostate cancer, helping men avoid unnecessary biopsies

Researchers at the University of Michigan Rogel Cancer Center have developed a new urine-based test that addresses a major problem in prostate cancer: how to separate the slow-growing form of the disease unlikely to cause harm from more aggressive cancer that needs immediate treatment.

The test, called MyProstateScore2.0, or MPS2, looks at 18 different genes linked to high-grade prostate cancer. In multiple tests using urine and tissue samples from men with prostate cancer, it successfully identified cancers classified as Gleason 3+4=7 or Grade Group 2 (GG2), or higher. These cancers are more likely to grow and spread compared to Gleason 6 or Grade Group 1 prostate cancers, which are unlikely to spread or cause other impact. More than one-third of prostate cancer diagnoses are this low-grade form. Gleason and Grade Group are both used to classify how aggressive prostate cancer is.

Results are published in JAMA Oncology.

“Our standard test is lacking in terms of its ability to clearly pick out those who have significant cancer. Twenty years ago, we were looking for any kind of cancer. Now we realize that slow-growing cancer doesn’t need to be treated. All of a sudden, the game changed. We went from having to find any cancer to finding only significant cancer,” said co-senior study author John T. Wei, M.D., David A. Bloom Professor of Urology at Michigan Medicine.

Prostate-specific antigen, or PSA, remains the linchpin of prostate cancer detection. MPS2 improves upon a urine-based test developed by the same U-M team nearly a decade ago, following a landmark discovery of two genes that fuse to cause prostate cancer. The original MPS test, which is used today, looked at PSA, the gene fusion TMPRSS2::ERG, and another marker called PCA3.

“There was still an unmet need with the MyProstateScore test and other commercial tests currently available. They were detecting prostate cancer, but in general they were not doing as good a job in detecting high-grade or clinically significant prostate cancer. The impetus for this new test is to address this unmet need,” said co-senior author Arul M. Chinnaiyan, M.D., Ph.D., director of the Michigan Center for Translational Pathology. Chinnaiyan’s lab discovered the T2::ERG gene fusion and developed the initial MPS test.

To make MyProstateScore even stronger at identifying high-grade cancers, researchers used RNA sequencing of more than 58,000 genes and narrowed it to 54 candidates uniquely overexpressed specifically in higher-grade cancers. They tested the biomarkers against urine samples collected and stored at U-M through another major study, the National Cancer Institute’s Early Detection Research Network. This included about 700 patients from 2008-2020 who came for a prostate biopsy due to an elevated PSA level.

This first step narrowed the field to 18 markers that consistently correlated with higher grade disease. The test still includes the original MPS markers, plus 16 additional biomarkers to complement them.

From there, the team reached out to the larger Early Detection Research Network (EDRN), a consortium of more than 30 labs across the country that are similarly collecting samples. This ensured a diverse, national sampling. Knowing no specific details about the samples, the U-M team performed MPS2 testing on more than 800 urine samples and sent results back to collaborators at the NCI-EDRN. The NCI-EDRN team assessed MPS2 results against the patient records.

MPS2 was shown to be better at identifying GG2 or higher cancers. More importantly, it was nearly 100% correct at ruling out GG1 cancer.

“If you’re negative on this test, it’s almost certain that you don’t have aggressive prostate cancer,” said Chinnaiyan, S. P. Hicks Endowed Professor of Pathology and professor of urology at Michigan Medicine.

Moreover, MPS2 was more effective at helping patients avoid unnecessary biopsies. While 11% of unnecessary biopsies were avoided with PSA testing alone, MPS2 testing would avoid up to 41% of unnecessary biopsies.

“Four of 10 men who would have a negative biopsy will have a low risk MPS2 result and can confidently skip a biopsy. If a man has had a biopsy before, the test works even better,” Wei explained.

For example, a patient may get a prostate biopsy due to an elevated PSA, but no cancer is detected. The patient is followed over time and if his PSA inches up, he would typically need another biopsy.

“In those men who have had a biopsy before and are being considered for another biopsy, MPS2 will identify half of those whose repeat biopsy would be negative. Those are practical applications for patients out there. Nobody wants to say sign me up for another biopsy. We are always looking for alternatives and this is it,” Wei said.

MPS2 is currently available through LynxDx, which is University of Michigan spin-off company that has an exclusive license from the university to commercialize MPS2. Patients interested in learning more can call the Michigan Medicine Cancer AnswerLine at 800-865-1125.

The paper’s first authors are Jeffrey J. Tosoian, M.D., M.P.H., who is now at Vanderbilt University, and Yuping Zhang, Ph.D., and Lanbo Xiao, Ph.D., at U-M. Additional authors are Cassie Xie; Nathan L. Samora, M.D.; Yashar S. Niknafs, Ph.D.; Zoey Chopra; Javed Siddiqui; Heng Zheng, M.D.; Grace Herron; Neil Vaishampayan; Hunter S. Robinson, M.D.; Kumaran Arivoli; Bruce J. Trock, Ph.D.; Ashley E. Ross, M.D., Ph.D.; Todd M. Morgan, M.D.; Ganesh S. Palapattu, M.D.; Simpa S. Salami, M.D., M.P.H.; Lakshmi P. Kunju, M.D.; Scott A. Tomlins, M.D., Ph.D.; Lori J. Sokoll, Ph.D.; Daniel W. Chan, Ph.D.; Sudhir Srivastava, Ph.D.; Ziding Feng, Ph.D.; Martin G. Sanda, M.D.; Yingye Zheng, Ph.D.

Funding for this work is from the Michigan-Vanderbilt Early Detection Research Network Biomarker Characterization Center and Data Management and Coordinating Center, which are through the National Cancer Institute grants U2C CA271854 and U24 CA086368. Additional funding is from NCI grants P50 CA186786, R35 CA231996, U24 CA115102, U01 CA113913; Prostate Cancer Foundation; Howard Hughes Medical Institute; and the American Cancer Society.

Disclosures: Chinnaiyan serves on the advisory boards of Tempus, LynxDx, Ascentage Pharmaceuticals, Medsyn therapeutics, Esanik and RAAPTA therapeutics. Tomlins is an equity holder and chief medical officer of Strata Oncology. LynxDx has obtained an exclusive license from the University of Michigan to commercialize MPS2 and the TMPRSS2-ERG gene fusion. Tosoian and Chinnaiyan are equity holders and scientific advisers to LynxDx. Siddiqui, Zhang, Xiao and Niknafs have served as scientific advisers to LynxDx.

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More young, affluent women may be smoking – study

Younger women could benefit from targeted interventions to tackle the apparent rise, researchers say.

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