47 research outputs found

    Experimental system to displace radioisotopes from upper to deeper soil layers: chemical research

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    BACKGROUND: Radioisotopes are introduced into the environment following nuclear power plant accidents or nuclear weapons tests. The immobility of these radioactive elements in uppermost soil layers represents a problem for human health, since they can easily be incorporated in the food chain. Preventing their assimilation by plants may be a first step towards the total recovery of contaminated areas. METHODS: The possibility of displacing radionuclides from the most superficial soil layers and their subsequent stabilisation at lower levels were investigated in laboratory trials. An experimental system reproducing the environmental conditions of contaminated areas was designed in plastic columns. A radiopolluted soil sample was treated with solutions containing ions normally used in fertilisation (NO(3)(-), NH(4)(+), PO(4)(--- )and K(+)). RESULTS: Contaminated soils treated with an acid solution of ions NO(3)(-), PO(4)(--- )and K(+), undergo a reduction of radioactivity up to 35%, after a series of washes which simulate one year's rainfall. The capacity of the deepest soil layers to immobilize the radionuclides percolated from the superficial layers was also confirmed. CONCLUSION: The migration of radionuclides towards deeper soil layers, following chemical treatments, and their subsequent stabilization reduces bioavailability in the uppermost soil horizon, preventing at the same time their transfer into the water-bearing stratum

    Endoscopic internal drainage for the management of leak, fistula, and collection after sleeve gastrectomy: our experience in 617 consecutive patients

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    Background: Endoscopy plays a pivotal role in the management of adverse events (AE) following bariatric surgery. Leaks, fistulae, and post-operative collection after sleeve gastrectomy (SG) may occur in up to 10% of cases. Objectives: To evaluate the efficacy and safety of endoscopic internal drainage (EID) for the management of leak, fistula, and collection following SG. Setting: Retrospective, observational, single center study on patients referred from several bariatric surgery departments to an endoscopic referral center. Methods: EID was used as first-line treatment for the management of leaks, fistulae, and collections. Leaks and fistulae were treated with double pigtail stent (DPS) deployment in order to guarantee internal drainage and second intention cavity obliteration. Collections were treated with endoscropic ultrasound (EUS)–guided deployment of DPS or lumen apposing metal stents. Results: A total of 617 patients (83.3% female; mean age, 43.1 yr) were enrolled in the study for leak (n = 300, 48.6%), fistula (n = 285, 46.2%), and collection (n = 32, 5.2%). Median follow-up was 19.5 months. Overall clinical success was 84.7% whereas 15.3% of cases required revisional surgery after EID failure. Clinical success according to type of AE was 89.5%, 78.5%, and 90% for leak, fistula, and collection, respectively. A total of 10 of 547 (1.8%) presented a recurrence during follow-up. A total of 28 (4.5%) AE related to the endoscopic treatment occurred. At univariate logistic regression predictors of failure were: fistula (OR 2.012), combined endoscopic approach (OR 2.319), need for emergency surgery (OR 1.755), and previous endoscopic treatment (OR 4.818). Conclusion: Early EID for the management of leak, fistula, and post-operative collection after SG seems a safe and effective first-line approach with good long-term results

    Biodiversity and structure of spider communities along a metal pollution gradient

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    The objective of the study was to determine whether long-term metal pollution affects communities of epigeal spiders (Aranea), studied at three taxonomic levels: species, genera, and families. Biodiversity was defined by three indices: the Hierarchical Richness Index (HRI), Margalef index (DM) and Pielou evenness index (J). In different ways the indices describe taxa richness and the distribution of individuals among taxa. The dominance pattern of the communities was described with four measures: number of dominant species at a site, percentage of dominant species at a site, average dominant species abundance at a site, and the share of the most numerous species (Alopecosa cuneata) at a site. Spiders were collected along a metal pollution gradient in southern Poland, extending ca. 33 km from zinc and lead smelter to an uncontaminated area. The zinc concentration in soil was used as the pollution index.The study revealed a significant effect of metal pollution on spider biodiversity as described by HRI for species (p = 0.039), genera (p = 0.0041) and families (p = 0.0147), and by DM for genera (p = 0.0259) and families (p = 0.0028). HRI correlated negatively with pollution level, while DM correlated positively. This means that although broadly described HRI diversity decreased with increasing pollution level, species richness increased with increasing contamination. Mesophilic meadows were generally richer. Pielou (J) did not show any significant correlations. There were a few evidences for the intermediate disturbance hypothesis: certain indices reached their highest values at moderate pollution levels rather than at the cleanest or most polluted sites

    Access to excluded structures after Roux-en-Y gastric bypass: experience in a high-level bariatric center without a technical platform for endoscopic retrograde cholangiopancreatography

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    Rapid weight loss after bariatric surgery is associated with a high prevalence of gallstone formation. In laparoscopic Roux-en-Y gastric bypass (RYGBP), the bypassed segment is not readily available for endoscopic or radiographic examination. We propose a laparoscopic Janeway gastrostomy for secondary access to excluded structures in bariatric centers with no mandatory technical equipment in endoscopic retrograde cholangiopancreatography (ERCP), double-balloon ERCP or spiral enteroscopy. METHOD: This was a single-institution retrospective review of a prospectively collected database of patients with a history of laparoscopic RYGBP who underwent laparoscopic Janeway gastrostomy for duodenal and biliary access. The operative indications, technical aspects, endoscopic findings, outcomes, and complications were investigated. RESULTS: Five patients with a history of RYGBP underwent laparoscopic Janeway gastrostomy for exploration of the bypassed segment. All of them had biliary pathology, and all underwent successful ERCP and papillotomy. The gastrostomies were closed secondarily. The mean duration of hospitalization was 12 days. No complications developed. All procedures were performed laparoscopically. CONCLUSION: If access to excluded structures and simultaneous ERCP was not possible, temporary laparoscopic Janeway gastrostomy could be the last option alternative for a staged ERCP to gain access to the bypassed structures. It is a feasible and safe solution for the exploration and treatment of patients with a history of RYGBP in bariatric centers that have no endoscopists with expertise in ERCP

    History and sensitivity comparison of the

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    The history of toxicity tests with duckweeds shows that these assays with free-floating aquatic angiosperms are gaining increasing attention in ecotoxicological research and applications. Standard tests have been published by national and international organizations, mainly with the test species Lemna minor and Lemna gibba. Besides the former two test species the great duckweed Spirodela polyrhiza is to date also regularly used in duckweed testing. Under unfavorable environmental conditions, the latter species produces dormant stages (turions) and this has triggered the attention of two research groups from Belgium and Greece to jointly develop a “stock culture independent” microbiotest with S. polyrhiza. A 72 h new test has been worked out which besides its independence of stock culturing and maintenance of live stocks is very simple and practical to perform, and much less demanding in space and time than the conventional duckweed tests. Extensive International Interlaboratory Comparisons on the S. polyrhiza microbiotest showed its robustness and reliability and triggered the decision to propose this new assay to the ISO for endorsement and publication as a standard toxicity test for duckweeds. Sensitivity comparison of the 72 h S. polyrhiza microbiotest with the 7d L. minor assay for 22 compounds belonging to different groups of chemicals revealed that based on growth as the effect criterion both duckweed assays have a similar sensitivity. Taking into account its multiple advantages and assets, the S. polyrhiza microbiotest is a reliable and attractive alternative to the conventional duckweed tests

    Endoscopic Fistula-jejunostomy for Chronic Gastro-jejunal Fistula After Sleeve Gastrectomy

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    Proximal gastric leak is one of the most common complications after laparoscopic sleeve gastrectomy (LSG). Endoscopy is the gold standard treatment for acute staple-line leaks. Surgery is the most effective treatment modality in case of chronic fistula. MATERIAL AND METHODS: A 55-year- old man presented an acute leak after LSG. The leak was treated with metal stent deployment with temporary closure. After 6 months, he presented leak recurrence with general sepsis, perigastric-infected collection, and gastro-jejunal fistula. RESULTS: Endoscopic internal drainage (EID) was performed; however, due to fistula persistence, a surgical procedure was proposed. The patient refused revisional surgery; therefore, endoscopic salvage procedure was decided. A fully covered metal stent was deployed in order to bypass the perigastric collection creating an endoscopic gastro-jejunal anastomosis. CONCLUSION: Revisional surgery is the gold standard treatment for chronic fistula after SG. Endoscopic treatment with SEMS deployment may be a sound option in selected cases especially after failure of other endoscopic techniques or refusal of revisional surgery

    History and sensitivity comparison of the Spirodela polyrhiza

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    The history of toxicity tests with duckweeds shows that these assays with free-floating aquatic angiosperms are gaining increasing attention in ecotoxicological research and applications. Standard tests have been published by national and international organizations, mainly with the test species Lemna minor and Lemna gibba. Besides the former two test species the great duckweed Spirodela polyrhiza is to date also regularly used in duckweed testing. Under unfavorable environmental conditions, the latter species produces dormant stages (turions) and this has triggered the attention of two research groups from Belgium and Greece to jointly develop a “stock culture independent” microbiotest with S. polyrhiza. A 72 h new test has been worked out which besides its independence of stock culturing and maintenance of live stocks is very simple and practical to perform, and much less demanding in space and time than the conventional duckweed tests. Extensive International Interlaboratory Comparisons on the S. polyrhiza microbiotest showed its robustness and reliability and triggered the decision to propose this new assay to the ISO for endorsement and publication as a standard toxicity test for duckweeds. Sensitivity comparison of the 72 h S. polyrhiza microbiotest with the 7d L. minor assay for 22 compounds belonging to different groups of chemicals revealed that based on growth as the effect criterion both duckweed assays have a similar sensitivity. Taking into account its multiple advantages and assets, the S. polyrhiza microbiotest is a reliable and attractive alternative to the conventional duckweed tests
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