These Canadian rocks may be the oldest on Earth
NEW YORK — Scientists have identified what could be the oldest rocks on Earth from a rock formation in Canada .
The Nuvvuagittuq Greenstone Belt has long been known for its ancient rocks — plains of streaked gray stone on the eastern shore of Hudson Bay in Quebec. But researchers disagree on exactly how old they are.
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Yahoo
an hour ago
- Yahoo
Scientists raise ‘urgent concerns' over new bat viruses discovered in China
Researchers have raised 'urgent concerns' after discovering two new bat viruses in China with the potential to infect humans and cause severe brain inflammation and respiratory disease. The viruses, along with multiple new bacteria and parasite species, were discovered in bats inhabiting orchards in southwestern China's Yunnan province, according to a study published on Tuesday in the journal PLoS Pathogens. These viruses are closely related to the deadly Nipah and Hendra pathogens, which cause severe brain inflammation and respiratory disease in humans, according to researchers, including from the Yunnan Institute of Endemic Disease Control and Prevention. Nipah is a lethal pathogen known to cause severe disease in humans, including acute respiratory distress with a high mortality rate of 35-75 per cent. The Hendra virus has been responsible for multiple fatal outbreaks in humans and horses. 'These viruses are naturally hosted by fruit bats and are typically transmitted to humans through bat urine or saliva, often via contamination of food sources,' researchers said. The study raises concerns about the potential for similar new viruses to spread from bats to livestock or humans in the region. 'This finding is particularly significant as Yunnan province is a recognised hotspot for bat diversity,' it notes. Due to their unique immune systems, bats are a natural reservoir for a wide range of microorganisms, including notable pathogens transmitted to humans. While the exact origins of the Covid-19 pandemic remain unclear, numerous studies suggest horseshoe bats as one of the most likely host candidates from which the novel coronavirus jumped to humans. However, the complete array of viruses, fungi, bacteria and parasites that infect bats remains unknown as most previous studies have focused on faeces from the flying mammal alone without inspecting the organs. The latest study peered inside the kidneys of 142 bats from 10 species, which were collected over four years across five areas of Yunnan. Genome sequencing of the samples revealed 22 viruses, of which 20 are new to science. Two of these were henipaviruses, the same genus as Nipah and Hendra, which have had high fatality rates in humans in previous epidemic outbreaks. Since these viruses can potentially spread through urine, scientists raise concerns about the risk of these pathogens jumping to humans or livestock via contaminated fruit from the orchards. The findings underscore the need for a multi-organ screening approach to understand the microbial diversity harboured by bats. Scientists call for 'comprehensive, full-spectrum microbial analyses of previously understudied organs to better assess spillover risks from bat populations'. "By analysing the infectome of bat kidneys collected near village orchards and caves in Yunnan, we uncovered not only the diverse microbes bats carry, but also the first full-length genomes of novel bat-borne henipaviruses closely related to Hendra and Nipah viruses identified in China,' they say. Researchers have also expressed 'urgent concerns about the potential for these viruses to spill over into humans or livestock'.
Medscape
an hour ago
- Medscape
Diabetes Drug Tied to Decreased Dementia Risk in T2D
TOPLINE: Semaglutide was associated with a 20%-46% reduced risk for Alzheimer's disease (AD)-related dementia in patients with type 2 diabetes (T2D) compared with other antidiabetic medications, with a particularly strong protective effect against vascular dementia, new research showed. METHODOLOGY: Researchers examined electronic health records (EHRs) of more than 1.7 million US adults with T2D with or without obesity and with no prior diagnosis of AD or AD-related dementia. They compared semaglutide (n = 64,267 users) to seven other antidiabetic medications (n = 1,646,728 users) on the first-time diagnosis of AD-related dementia, as well as the subtypes of vascular dementia, frontotemporal dementia (FTD), and Lewy body dementia, during a 3-year follow-up. The other antidiabetic medications included insulin, metformin, DPP-4 inhibitors, SGLT2 inhibitors, sulfonylurea, thiazolidinedione, and first-generation GLP-1 receptor agonists (albiglutide, dulaglutide, exenatide, liraglutide, and lixisenatide). Secondary outcomes included prescriptions of dementia-related medications. TAKEAWAY: Semaglutide was associated with a significantly reduced risk for AD-related dementia compared to insulin (hazard ratio [HR], 0.54), metformin (HR, 0.67), and older GLP-1 receptor agonists (HR, 0.80). Protection against vascular dementia was also greater for semaglutide compared to insulin (HR, 0.48), metformin (HR, 0.55), and GLP-1 receptor agonists (HR, 0.67). No significant associations were found between the use of semaglutide and the risk for FTD or Lewy body dementia. The link between semaglutide and reduced AD-related dementia risk vs insulin, metformin, and GLP-1 receptor agonists was stronger in younger adults (mean age, 51.7 years) compared to older adults (mean age, 70.9 years), with risk reductions ranging from 32% to 56% vs 20% to 39%. The use of semaglutide vs other antidiabetic medications was associated with significantly fewer prescriptions of dementia-related medications. IN PRACTICE: 'There is no cure or effective treatment for dementia, so this new study provides real-world evidence for its potential impact on preventing or slowing dementia development among at high-risk population,' Rong Xu, Case Western Reserve University School of Medicine, Cleveland, said in a press release. 'Future works are needed to establish causal relationships through randomized clinical trials and to characterize the underlying mechanisms,' the investigators wrote. SOURCE: This study was led by William Wang, Case Western Reserve University School of Medicine, Cleveland. It was published online on June 24 in the Journal of Alzheimer's Disease. LIMITATIONS: This retrospective, observational, EHR-based study was limited by potential over-, under-, or misdiagnosis; unmeasured confounders; and a short 3-year follow-up period. Diagnosis of AD-related dementia relied on International Classification of Diseases, 10th Revision codes and prescription data, which may have lacked precision. This study also lacked data on medication adherence, cognitive function tracking, and genetic profiles, and could not fully adjust for variation of healthcare use. DISCLOSURES: This study was funded by grants from the National Institute on Aging and the National Center for Advancing Translational Sciences. One investigator reported being the editor in chief of the publishing journal but was not involved in the peer-review process. The other investigators reported having no relevant financial conflicts. This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.
Medscape
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IV Dexamethasone Cuts Postblock Pain After Hand Surgery
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