39 research outputs found

    DNA repair during nonreductional meiosis in the asexual rotifer Adineta vaga

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    Rotifers of the class Bdelloidea are microscopic animals notorious for their long-term persistence in the apparent absence of sexual reproduction and meiotic recombination. This evolutionary paradox is often counterbalanced by invoking their ability to repair environmentally induced genome breakage. By studying the dynamics of DNA damage response in the bdelloid species , we found that it occurs rapidly in the soma, producing a partially reassembled genome. By contrast, germline DNA repair is delayed to a specific time window of oogenesis during which homologous chromosomes adopt a meiotic-like juxtaposed configuration, resulting in accurate reconstitution of the genome in the offspring. Our finding that a noncanonical meiosis is the mechanism of germline DNA repair in bdelloid rotifers gives previously unidentified insights on their enigmatic long-term evolution

    Strategies for the delay of surgery in the management of resectable hepatobiliary malignancies during the COVID-19 pandemic

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    Objective: We aimed to review data about delaying strategies for the management of hepatobiliary cancers requiring surgery during the covid-19 pandemic. Background: Given the covid-19 pandemic, many jurisdictions, to spare resources, have limited access to operating rooms for elective surgical activity, including cancer, thus forcing deferral or cancellation of cancer surgeries. Surgery for hepatobiliary cancer is high-risk and particularly resource-intensive. Surgeons must critically appraise which patients will benefit most from surgery and which ones have other therapeutic options to delay surgery. Little guidance is currently available about potential delaying strategies for hepatobiliary cancers when surgery is not possible. Methods: An international multidisciplinary panel reviewed the available literature to summarize data relating to standard-of-care surgical management and possible mitigating strategies to be used as a bridge to surgery for colorectal liver metastases, hepatocellular carcinoma, gallbladder cancer, intrahepatic cholangiocarcinoma, and hilar cholangiocarcinoma. Results: Outcomes of surgery during the covid-19 pandemic are reviewed. Resource requirements are summarized, including logistics and adverse effects profiles for hepatectomy and delaying strategies using systemic, percutaneous and radiation ablative, and liver embolic therapies. For each cancer type, the long-term oncologic outcomes of hepatectomy and the clinical tools that can be used to prognosticate for individual patients are detailed. Conclusions: There are a variety of delaying strategies to consider if availability of operating rooms decreases. This review summarizes available data to provide guidance about possible delaying strategies depending on patient, resource, institution, and systems factors. Multidisciplinary team discussions should be leveraged to consider patient- and tumour-specific information for each individual case.publishedVersio

    Immediate and long-term impact of the COVID-19 pandemic on delivery of surgical services

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    Background The ongoing pandemic is having a collateral health effect on delivery of surgical care to millions of patients. Very little is known about pandemic management and effects on other services, including delivery of surgery. Methods This was a scoping review of all available literature pertaining to COVID‐19 and surgery, using electronic databases, society websites, webinars and preprint repositories. Results Several perioperative guidelines have been issued within a short time. Many suggestions are contradictory and based on anecdotal data at best. As regions with the highest volume of operations per capita are being hit, an unprecedented number of operations are being cancelled or deferred. No major stakeholder seems to have considered how a pandemic deprives patients with a surgical condition of resources, with patients disproportionally affected owing to the nature of treatment (use of anaesthesia, operating rooms, protective equipment, physical invasion and need for perioperative care). No recommendations exist regarding how to reopen surgical delivery. The postpandemic evaluation and future planning should involve surgical services as an essential part to maintain appropriate surgical care for the population during an outbreak. Surgical delivery, owing to its cross‐cutting nature and synergistic effects on health systems at large, needs to be built into the WHO agenda for national health planning. Conclusion Patients are being deprived of surgical access, with uncertain loss of function and risk of adverse prognosis as a collateral effect of the pandemic. Surgical services need a contingency plan for maintaining surgical care in an ongoing or postpandemic phase.publishedVersio

    Étude du comportement de prédation du martin-pêcheur Alcedo atthis (L.) : taille préférentielle de capture du chabot Cottus gobio L. et de la truite Salmo trutta L.

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    Prey size selection by the Europe an kingfisher Alcedo atthis has been studied from 1975 to 1977 in a breeding population along the Lesse River, Belgium. The size of the fish taken changes with age of the nestlings. During the first ten days of the rearing period fish of a small size are caught more frequently than large ones. On the other hand, larger fish are caught and brought back to the nest as soon as the fledglings are able to ingest them. The portion of the fish population preyed upon by kingfishers has also been identified. Fry is caught as soon as it reaches 1.5 to 2.0 cm in length ; larger fry (up to 4 cm long) is only actively saught during the rearing period of young nestlings. Fish 4 to 7 cm long are the most frequently preyed upon, the largest ones measuring 10 cm lon

    Le martin pêcheur: un ambassadeur haut en couleur pour un milieu menacé

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    Contribution to the identification of skull remains of freshwater fishes from Belgium and Northern France. 2 Cypriniformes

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    peer reviewedOutline drawings of the most typical skull bones of 23 Cypriniformes species (dentary, maxillary, pharyngeal bone) are presented. The main distinctive morphological features are summarized into identification keys. Biometrical relationships also computed for eigth common species (Gudgeon, Bleak, Rudd, Roach, Common bream, Carp, Tench and the Stone loach)

    The European otter in Belgium today: conservation problems

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    Widespread all over the country till the end of the last century, the otter has rapidly declined. In 1973 when hunting was definitely closed, the otter was already threatened and restricted to a few localities. In 1889, the Belgian Ministry of agriculture decided to pay bounties for otters, a system which was cancelled only in 1963. Game statistics of the past century allow the annual otter bag to evaluated as roughly 25 % of the standing population. As it is the case in other European industrialised countries, freshwater habitat loss and water pollution lead to a considerable decrease of the river carrying capacity. Almost all the rivers flowing in the Northern part of Belgium are now lifeless or at least in a very bad condition. South of the river Meuse, some accidental pollutions are regularly reported (chloring in the river Ourthe in 1993; chloracetic acid in the Sûre in 1990...) and the level of organic pollution rises from year to year. Moreover, the tourism (angling, camp sites, kayak) nare more and more intensive leading to major disturbances, particularly during the summer months. Finally, the Ministery of equipment is developing a policy of big hydraulic works (dams, embankments, dredging...) along the river Ourthe, one of the last to be occupied by a few otters
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