59 research outputs found

    Context Differences Reveal Insulator and Activator Functions of a Su(Hw) Binding Region

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    Insulators are DNA elements that divide chromosomes into independent transcriptional domains. The Drosophila genome contains hundreds of binding sites for the Suppressor of Hairy-wing [Su(Hw)] insulator protein, corresponding to locations of the retroviral gypsy insulator and non-gypsy binding regions (BRs). The first non-gypsy BR identified, 1A-2, resides in cytological region 1A. Using a quantitative transgene system, we show that 1A-2 is a composite insulator containing enhancer blocking and facilitator elements. We discovered that 1A-2 separates the yellow (y) gene from a previously unannotated, non-coding RNA gene, named yar for y-achaete (ac) intergenic RNA. The role of 1A-2 was elucidated using homologous recombination to excise these sequences from the natural location, representing the first deletion of any Su(Hw) BR in the genome. Loss of 1A-2 reduced yar RNA accumulation, without affecting mRNA levels from the neighboring y and ac genes. These data indicate that within the 1A region, 1A-2 acts an activator of yar transcription. Taken together, these studies reveal that the properties of 1A-2 are context-dependent, as this element has both insulator and enhancer activities. These findings imply that the function of non-gypsy Su(Hw) BRs depends on the genomic environment, predicting that Su(Hw) BRs represent a diverse collection of genomic regulatory elements

    Postoperative outcomes in oesophagectomy with trainee involvement

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    BACKGROUND: The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting. METHODS: Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups. RESULTS: Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005). CONCLUSION: Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery

    Performance of non-invasive tests and histology for the prediction of clinical outcomes in patients with non-alcoholic fatty liver disease: an individual participant data meta-analysis

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    BackgroundHistologically assessed liver fibrosis stage has prognostic significance in patients with non-alcoholic fatty liver disease (NAFLD) and is accepted as a surrogate endpoint in clinical trials for non-cirrhotic NAFLD. Our aim was to compare the prognostic performance of non-invasive tests with liver histology in patients with NAFLD.MethodsThis was an individual participant data meta-analysis of the prognostic performance of histologically assessed fibrosis stage (F0–4), liver stiffness measured by vibration-controlled transient elastography (LSM-VCTE), fibrosis-4 index (FIB-4), and NAFLD fibrosis score (NFS) in patients with NAFLD. The literature was searched for a previously published systematic review on the diagnostic accuracy of imaging and simple non-invasive tests and updated to Jan 12, 2022 for this study. Studies were identified through PubMed/MEDLINE, EMBASE, and CENTRAL, and authors were contacted for individual participant data, including outcome data, with a minimum of 12 months of follow-up. The primary outcome was a composite endpoint of all-cause mortality, hepatocellular carcinoma, liver transplantation, or cirrhosis complications (ie, ascites, variceal bleeding, hepatic encephalopathy, or progression to a MELD score ≥15). We calculated aggregated survival curves for trichotomised groups and compared them using stratified log-rank tests (histology: F0–2 vs F3 vs F4; LSM: 2·67; NFS: 0·676), calculated areas under the time-dependent receiver operating characteristic curves (tAUC), and performed Cox proportional-hazards regression to adjust for confounding. This study was registered with PROSPERO, CRD42022312226.FindingsOf 65 eligible studies, we included data on 2518 patients with biopsy-proven NAFLD from 25 studies (1126 [44·7%] were female, median age was 54 years [IQR 44–63), and 1161 [46·1%] had type 2 diabetes). After a median follow-up of 57 months [IQR 33–91], the composite endpoint was observed in 145 (5·8%) patients. Stratified log-rank tests showed significant differences between the trichotomised patient groups (p<0·0001 for all comparisons). The tAUC at 5 years were 0·72 (95% CI 0·62–0·81) for histology, 0·76 (0·70–0·83) for LSM-VCTE, 0·74 (0·64–0·82) for FIB-4, and 0·70 (0·63–0·80) for NFS. All index tests were significant predictors of the primary outcome after adjustment for confounders in the Cox regression.InterpretationSimple non-invasive tests performed as well as histologically assessed fibrosis in predicting clinical outcomes in patients with NAFLD and could be considered as alternatives to liver biopsy in some cases

    Evaluation of appendicitis risk prediction models in adults with suspected appendicitis

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    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

    Anti-hyperalgesic and anti-inflammatory effects of Achillea santolina and Stachys athorecalyx extracts on complete Freund's adjuvant–induced short- term inflammation in male wistar rats

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    Introduction: Immune system is involved in the etiology and path physiologic mechanisms of inflammation. Medicinal plants are an important source of substances which are claimed to induce non-specific immune modulator effects. Given the above information and the role of IL-6 in inflammation and pain induction, this study investigated the effects of Achillea santolina and Stachys athorecalyx methanolic and defatted extracts on cmplete Freund's adjuvant (CFA) -induced short term inflammation in male Wistar rats Materials and Methods: Inflammation was induced on day zero by CFA injection in hind paw of rats. Methanolic and defatted extractions were prepared form aerial parts of both plants. 50, 100 and 200 mg/kg doses of extracts were selected for IP treatment during 6 days after CFA injection. Results: Results indicated dose related effects of A. santolina and S. athorecalyx extracts on edema, hyperalgesia and serum IL-6 level during inflammation. Although, both methanolic and defatted extracts of S. athorecalyx showed a significant reduction in the inflammatory symptoms, no significant differences was observed between these two kinds of extracts of S.athorecalyx with respect to their anti inflammatory effects. Only methanolic extract of A. santolina was effective during CFA-induced inflammation. Conclusion: These results could suggest that short-term administration of A. santolina and S. athorecalyx extracts possess potent anti-inflammatory effects and modulate paw edema, hyperalgesia and serum IL-6 level during CFA–induced inflammation. In addition, these dose-dependent effects may mediate via different extract supplements which need more investigations

    Long-Term Treatment by Vitamin B1 and Reduction of Serum Proinflammatory Cytokines, Hyperalgesia, and Paw Edema in Adjuvant-Induced Arthritis

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    Introduction: Immune system is involved in the etiology and pathophysiology of inflammation and vitamins are important sources of substances inducing nonspecific immunomodulatory effects. Given the proinflammatory role of cytokines in the inflammation and pain induction, this study aimed to assess the effects of long-term administration of vitamin B1 on the proinflammatory cytokines, edema, and hyperalgesia during the acute and chronic phases of adjuvant-induced arthritis.&nbsp; Methods: On the first day of study, inflammation was induced by intraplantar injection of complete Freund&rsquo;s adjuvant (CFA) in the hindpaws of rats. Vitamin B1 at doses of 100, 150, and 200 mg/kg was administrated intraperitoneally during 21 days of the study. Antinociceptive and anti-inflammatory effects of vitamin B1 were also compared to indomethacin (5 mg/kg). Inflammatory symptoms such as thermal hyperalgesia and paw edema were measured by radiant heat and plethysmometer, respectively. Serum TNF-&alpha; and IL-1&szlig; levels were checked by rat standard enzyme-linked immune sorbent assay (ELISA) specific kits.&nbsp; Results: The results indicated that vitamin B1(150 and 200 mg/kg) attenuated the paw edema, thermal hyperalgesia, and serum levels of TNF-&alpha; and IL-1&szlig; during both phases of CFA-induced inflammation in a dose-dependent manner. Effective dose of vitamin B1(150 mg/kg) reduced inflammatory symptoms and serum levels of TNF-&alpha; and IL-1&szlig; compare to indomethacin during the chronic phase of inflammation.&nbsp; Conclusion: Anti-inflammatory and antihyperalgesic effects of vitamin B1 during CFA-induced arthritis, more specifically after chronic vitamin B1 administration, suggest its therapeutic property for inflammation

    Long-Term Treatment by Vitamin B1 and Reduction of Serum Proinflammatory Cytokines, Hyperalgesia, and Paw Edema in Adjuvant-Induced Arthritis

    No full text
    Introduction: Immune system is involved in the etiology and pathophysiology of inflammation and vitamins are important sources of substances inducing nonspecific immunomodulatory effects. Given the proinflammatory role of cytokines in the inflammation and pain induction, this study aimed to assess the effects of long-term administration of vitamin B1 on the proinflammatory cytokines, edema, and hyperalgesia during the acute and chronic phases of adjuvant-induced arthritis.&nbsp; Methods: On the first day of study, inflammation was induced by intraplantar injection of complete Freund&rsquo;s adjuvant (CFA) in the hindpaws of rats. Vitamin B1 at doses of 100, 150, and 200 mg/kg was administrated intraperitoneally during 21 days of the study. Antinociceptive and anti-inflammatory effects of vitamin B1 were also compared to indomethacin (5 mg/kg). Inflammatory symptoms such as thermal hyperalgesia and paw edema were measured by radiant heat and plethysmometer, respectively. Serum TNF-&alpha; and IL-1&szlig; levels were checked by rat standard enzyme-linked immune sorbent assay (ELISA) specific kits.&nbsp; Results: The results indicated that vitamin B1(150 and 200 mg/kg) attenuated the paw edema, thermal hyperalgesia, and serum levels of TNF-&alpha; and IL-1&szlig; during both phases of CFA-induced inflammation in a dose-dependent manner. Effective dose of vitamin B1(150 mg/kg) reduced inflammatory symptoms and serum levels of TNF-&alpha; and IL-1&szlig; compare to indomethacin during the chronic phase of inflammation.&nbsp; Conclusion: Anti-inflammatory and antihyperalgesic effects of vitamin B1 during CFA-induced arthritis, more specifically after chronic vitamin B1 administration, suggest its therapeutic property for inflammation
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