El macrobentos y su relación con las fluctuaciones de salinidad en ríos y esteros del Chaco Oriental (Argentina)

In the area comprised between the Pilcomayo river (Formosa province) and the Amores river (Santa Fe province) 17 streams and rivers, and 4 swamps ("esteros") were studied in their lower reaches during low and high water periods. The salinity was high in some of them, specially during low water. Samples were taken with a Dietz-LaFond and modified Drzycimski dredges, according to the substrate characteristics, and filteres through a 500μm mesh size. Relative abundance and density (ind. m-2) were analized in relation with the main environmental factors, as current speed, conductivity, dissolved oxigen and sediment granulometry. The benthic macrofauna occurring in the streams and rivers showed important differences in their composition and density, being oligochaetes (Naididae and Tubificidae), chironomids (Chironominae) and molluscs (Hydrobiidae), the main groups.The swamp bottom fauna was rather poor, with abundance of oligochaetes, which could be due to the scarcity of dissolved oxygen and the high proportion of organic matter. The well oxigenated lotic environments, with moderate conductivity values, showed the richest and most abundant macrofauna, in contrast with those of high salinity, specially when the water level decreased. Conductivity was negatively correlated with the species number ( P < 0,01) and abundance (P< 0,01).In the area comprised between the Pilcomayo river (Formosa province) and the Amores river (Santa Fe province) 17 streams and rivers, and 4 swamps ("esteros") were studied in their lower reaches during low and high water periods. The salinity was high in some of them, specially during low water. Samples were taken with a Dietz-LaFond and modified Drzycimski dredges, according to the substrate characteristics, and filteres through a 500μm mesh size. Relative abundance and density (ind. m-2) were analized in relation with the main environmental factors, as current speed, conductivity, dissolved oxigen and sediment granulometry. The benthic macrofauna occurring in the streams and rivers showed important differences in their composition and density, being oligochaetes (Naididae and Tubificidae), chironomids (Chironominae) and molluscs (Hydrobiidae), the main groups.The swamp bottom fauna was rather poor, with abundance of oligochaetes, which could be due to the scarcity of dissolved oxygen and the high proportion of organic matter. The well oxigenated lotic environments, with moderate conductivity values, showed the richest and most abundant macrofauna, in contrast with those of high salinity, specially when the water level decreased. Conductivity was negatively correlated with the species number ( P < 0,01) and abundance (P< 0,01)

Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

Background Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis. Methods A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis). Results Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent). Conclusion Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified

Genomic investigations of unexplained acute hepatitis in children

Since its first identification in Scotland, over 1,000 cases of unexplained paediatric hepatitis in children have been reported worldwide, including 278 cases in the UK1. Here we report an investigation of 38 cases, 66 age-matched immunocompetent controls and 21 immunocompromised comparator participants, using a combination of genomic, transcriptomic, proteomic and immunohistochemical methods. We detected high levels of adeno-associated virus 2 (AAV2) DNA in the liver, blood, plasma or stool from 27 of 28 cases. We found low levels of adenovirus (HAdV) and human herpesvirus 6B (HHV-6B) in 23 of 31 and 16 of 23, respectively, of the cases tested. By contrast, AAV2 was infrequently detected and at low titre in the blood or the liver from control children with HAdV, even when profoundly immunosuppressed. AAV2, HAdV and HHV-6 phylogeny excluded the emergence of novel strains in cases. Histological analyses of explanted livers showed enrichment for T cells and B lineage cells. Proteomic comparison of liver tissue from cases and healthy controls identified increased expression of HLA class 2, immunoglobulin variable regions and complement proteins. HAdV and AAV2 proteins were not detected in the livers. Instead, we identified AAV2 DNA complexes reflecting both HAdV-mediated and HHV-6B-mediated replication. We hypothesize that high levels of abnormal AAV2 replication products aided by HAdV and, in severe cases, HHV-6B may have triggered immune-mediated hepatic disease in genetically and immunologically predisposed children

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries