43 research outputs found

    Biochemical and mutagenic analysis of I-CreII reveals distinct but important roles for both the H-N-H and GIY-YIG motifs

    Get PDF
    Homing endonucleases typically contain one of four conserved catalytic motifs, and other elements that confer tight DNA binding. I-CreII, which catalyzes homing of the Cr.psbA4 intron, is unusual in containing two potential catalytic motifs, H-N-H and GIY-YIG. Previously, we showed that cleavage by I-CreII leaves ends (2-nt 3′ overhangs) that are characteristic of GIY-YIG endonucleases, yet it has a relaxed metal requirement like H-N-H enzymes. Here we show that I-CreII can bind DNA without an added metal ion, and that it binds as a monomer, akin to GIY-YIG enzymes. Moreover, cleavage of supercoiled DNA, and estimates of strand-specific cleavage rates, suggest that I-CreII uses a sequential cleavage mechanism. Alanine substitution of a number of residues in the GIY-YIG motif, however, did not block cleavage activity, although DNA binding was substantially reduced in several variants. Substitution of conserved histidines in the H-N-H motif resulted in variants that did not promote DNA cleavage, but retained high-affinity DNA binding—thus identifying it as the catalytic motif. Unlike the non-specific H-N-H colicins, however; substitution of the conserved asparagine substantially reduced DNA binding (though not the ability to promote cleavage). These results indicate that, in I-CreII, two catalytic motifs have evolved to play important roles in specific DNA binding. The data also indicate that only the H-N-H motif has retained catalytic ability

    The SCARE Statement: Consensus-based surgical case report guidelines

    Get PDF
    AbstractIntroductionCase reports have been a long held tradition within the surgical literature. Reporting guidelines can improve transparency and reporting quality. However, recent consensus-based guidelines for case reports (CARE) are not surgically focused. Our objective was to develop surgical case report guidelines.MethodsThe CARE statement was used as the basis for a Delphi consensus. The Delphi questionnaire was administered via Google Forms and conducted using standard Delphi methodology. A multidisciplinary group of surgeons and others with expertise in the reporting of case reports were invited to participate. In round one, participants stated how each item of the CARE statement should be changed and what additional items were needed. Revised and additional items from round one were put forward into a further round, where participants voted on the extent of their agreement with each item, using a nine-point Likert scale, as proposed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) working group.ResultsIn round one, there was a 64% (38/59) response rate. Following adjustment of the guideline with the incorporation of recommended changes, round two commenced and there was an 83% (49/59) response rate. All but one of the items were approved by the participants, with Likert scores 7–9 awarded by >70% of respondents. The final guideline consists of a 14-item checklist.ConclusionWe present the SCARE Guideline, consisting of a 14-item checklist that will improve the reporting quality of surgical case reports

    Cerebral cortical thickness in chronic pain due to knee osteoarthritis: the effect of pain duration and pain densitization

    Get PDF
    Objective This study investigates associations between cortical thickness and pain duration, and central sensitization as markers of pain progression in painful knee osteoarthritis. Methods Whole brain cortical thickness and pressure pain thresholds were assessed in 70 participants; 40 patients with chronic painful knee osteoarthritis (age = 66.1± 8.5 years, 21 females, mean duration of pain = 8.5 years), and 30 healthy controls (age = 62.7± 7.4, 17 females). Results Cortical thickness negatively correlated with pain duration mainly in fronto-temporal areas outside of classical pain processing areas (p<0.05, age-controlled, FDR corrected). Pain sensitivity was unrelated to cortical thickness. Patients showed lower cortical thickness in the right anterior insula (p<0.001, uncorrected) with no changes surviving multiple test correction. Conclusion With increasing number of years of suffering from chronic arthritis pain we found increasing cortical thinning in extended cerebral cortical regions beyond recognised pain-processing areas. While the mechanisms of cortical thinning remain to be elucidated, we show that pain progression indexed by central sensitization does not play a major role

    The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

    Get PDF
    Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

    The SCARE Statement: Consensus-based surgical case report guidelines

    Get PDF
    Introduction: Case reports have been a long held tradition within the surgical literature. Reporting guidelines can improve transparency and reporting quality. However, recent consensus-based guidelines for case reports (CARE) are not surgically focused. Our objective was to develop surgical case report guidelines.Methods: The CARE statement was used as the basis for a Delphi consensus. The Delphi questionnaire was administered via Google Forms and conducted using standard Delphi methodology. A multidisciplinary group of surgeons and others with expertise in the reporting of case reports were invited to participate. In round one, participants stated how each item of the CARE statement should be changed and what additional items were needed. Revised and additional items from round one were put forward into a further round, where participants voted on the extent of their agreement with each item, using a nine-point Likert scale, as proposed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) working group.Results: In round one, there was a 64% (38/59) response rate. Following adjustment of the guideline with the incorporation of recommended changes, round two commenced and there was an 83% (49/59) response rate. All but one of the items were approved by the participants, with Likert scores 7–9 awarded by >70% of respondents. The final guideline consists of a 14-item checklist.Conclusion: We present the SCARE Guideline, consisting of a 14-item checklist that will improve the reporting quality of surgical case reports.</p

    The IDENTIFY study: the investigation and detection of urological neoplasia in patients referred with suspected urinary tract cancer - a multicentre observational study

    Get PDF
    Objective To evaluate the contemporary prevalence of urinary tract cancer (bladder cancer, upper tract urothelial cancer [UTUC] and renal cancer) in patients referred to secondary care with haematuria, adjusted for established patient risk markers and geographical variation. Patients and Methods This was an international multicentre prospective observational study. We included patients aged ≥16 years, referred to secondary care with suspected urinary tract cancer. Patients with a known or previous urological malignancy were excluded. We estimated the prevalence of bladder cancer, UTUC, renal cancer and prostate cancer; stratified by age, type of haematuria, sex, and smoking. We used a multivariable mixed-effects logistic regression to adjust cancer prevalence for age, type of haematuria, sex, smoking, hospitals, and countries. Results Of the 11 059 patients assessed for eligibility, 10 896 were included from 110 hospitals across 26 countries. The overall adjusted cancer prevalence (n = 2257) was 28.2% (95% confidence interval [CI] 22.3–34.1), bladder cancer (n = 1951) 24.7% (95% CI 19.1–30.2), UTUC (n = 128) 1.14% (95% CI 0.77–1.52), renal cancer (n = 107) 1.05% (95% CI 0.80–1.29), and prostate cancer (n = 124) 1.75% (95% CI 1.32–2.18). The odds ratios for patient risk markers in the model for all cancers were: age 1.04 (95% CI 1.03–1.05; P < 0.001), visible haematuria 3.47 (95% CI 2.90–4.15; P < 0.001), male sex 1.30 (95% CI 1.14–1.50; P < 0.001), and smoking 2.70 (95% CI 2.30–3.18; P < 0.001). Conclusions A better understanding of cancer prevalence across an international population is required to inform clinical guidelines. We are the first to report urinary tract cancer prevalence across an international population in patients referred to secondary care, adjusted for patient risk markers and geographical variation. Bladder cancer was the most prevalent disease. Visible haematuria was the strongest predictor for urinary tract cancer

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

    Get PDF
    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
    corecore