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To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes—although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms.

ObjectiveDetermine whether impairments in lower limb muscle strength exist in individuals with chronic ankle instability (CAI) compared with uninjured controls.DesignSystematic review with meta-analysis.Data sourceA comprehensive search of PubMed, Cochrane, CINAHL, Web of Science and EMBASE electronic databases from inception to 10 February 2019.Eligibility criteria for selecting studiesCross-sectional and case–control studies were included if they objectively measured lower limb muscle strength in individuals with CAI compared with controls. Risk of bias and quality of included studies were assessed. Data of included studies were extracted, and meta-analysis was conducted where appropriate.Results12 397 unique studies were identified, of which 20 were included and 16 were eligible for meta-analysis. Reviewed studies clearly described the aim/hypothesis and main outcome measure, but most lacked sample size calculation and assessor blinding. Meta-analyses showed individuals with CAI had lower eccentric and concentric evertor strength (30 and 120°/s; Nm; standardised mean difference (SMD) between −0.73 and −0.95), eccentric invertor strength (60 and 120°/s; both Nm and Nm/kg; SMD between −0.61 and −1.37), concentric invertor strength (60 and 120°/s; Nm; SMD=−0.7) and concentric knee extensor strength (SMD=−0.64) compared with control participants. Ankle eccentric dorsiflexor strength was not different between groups. Although pooling was not possible, data from three separate studies indicated that hip flexor, abductor and external rotator strength, but not hip adductor and extensor strength, was lower in individuals with CAI than in control participants.ConclusionIndividuals with CAI have ankle inversion and eversion strength deficits. Our data also point to differences between individuals with CAI and controls in hip and knee strength. These elements of the kinetic chain should be evaluated by clinicians who rehabilitate individuals with CAI.PROSPERO registration numberCRD42016037759.

Introduction The open abdomen (OA) is a necessary component of damage control surgery and closure is often challenging. Our aim was to review our ten-year experience with OA in trauma patients and to compare the success of a dual closure technique termed vacuum-assisted, mesh-mediated fascial traction (VAMMFT) to an exclusively Bogota Bag (BB) approach. Methods A retrospective analysis was performed using the HEMR database from 2012 to 2022, comparing demographics, mechanism of injury, admission vitals and biochemistry between patients with BB and VAMMFT applications. Rate of secondary abdominal closure and complications were assessed in both groups. Logistic regression was used to find predictors of closure. Results OA was required by 348 patients at index laparotomy. Of these, 133 (38.2%) were managed with VAMMFT and 215 (61.8%) exclusively with a BB. There were no statistical differences between the BB and VAMMFT groups in terms of demographics, injuries, admission vitals and biochemistry. The VAMMFT group achieved a closure rate of 73% compared to 54.9% in the BB group (OR of 2.2 [1.4–3.7]). There was no significant difference in fistulation rate between the two groups ( p  = 0.103). Length of hospital stay was 30 versus 17 days in the VAMMFT and BB groups, respectively (OR 1.41 [1.30–1.54]). There were no independent predictors of closure identified in the VAMMFT group. Older patients were less likely to achieve closure when BB was used (OR 0.97 [0.95–0.99]). VAMMFT failure was commonly due to lack of stock (39%) and protocol violations (33%). Conclusion The VAMMFT approach to the OA is efficacious and safe. VAMMFT achieves a much higher rate of secondary closure than BB alone with a low rate of enteric fistula formation.

We compared hip and knee isometric muscle torque between individuals with chronic ankle instability (CAI), those who have sustained one ankle sprain with no ongoing problems (copers) and healthy controls. Our secondary objective was to compare balance between groups and investigate the relationship between muscle torque and balance. Cross-sectional study. 22 CAI, 20 copers and 22 uninjured participants were tested. Isometric torque (normalised to body mass (Nm/kg)) was measured using a rigidly-fixated hand-held dynamometer. Balance was assessed with the Y-balance test. Knee and hip flexor and extensor, and hip adductor and abductor muscle torque was less in individuals with CAI compared to controls (standardised mean difference (SMD) >1.2). Hip and knee flexor and extensor muscle torque was less in CAI participants than copers (SMD: 0.69–1.1). Hip external and internal rotator torque did not differ between groups. There was no difference in hip or knee muscle torque between controls and copers (SMD: 0.01–0. 54). Balance was impaired in CAI participants compared to copers and controls in all directions. There was a strong positive correlation between posterolateral Y-balance test performance and torque of the hip adductors (r=0.53), flexors (r=0.52) and extensors (r=0.50). Individuals with CAI have weak knee and hip muscles compared to copers and controls. Hip strength was shown to be related to posterolateral balance performance. Future studies may investigate the effect of hip and knee strengthening exercise on ongoing ankle problems, such as episodic giving way in individuals with CAI.

Background Hallux valgus (HV) is a foot deformity commonly seen in medical practice, often accompanied by significant functional disability and foot pain. Despite frequent mention in a diverse body of literature, a precise estimate of the prevalence of HV is difficult to ascertain. The purpose of this systematic review was to investigate prevalence of HV in the overall population and evaluate the influence of age and gender. Methods Electronic databases (Medline, Embase, and CINAHL) and reference lists of included papers were searched to June 2009 for papers on HV prevalence without language restriction. MeSH terms and keywords were used relating to HV or bunions, prevalence and various synonyms. Included studies were surveys reporting original data for prevalence of HV or bunions in healthy populations of any age group. Surveys reporting prevalence data grouped with other foot deformities and in specific disease groups (e.g. rheumatoid arthritis, diabetes) were excluded. Two independent investigators quality rated all included papers on the Epidemiological Appraisal Instrument. Data on raw prevalence, population studied and methodology were extracted. Prevalence proportions and the standard error were calculated, and meta-analysis was performed using a random effects model. Results A total of 78 papers reporting results of 76 surveys (total 496,957 participants) were included and grouped by study population for meta-analysis. Pooled prevalence estimates for HV were 23% in adults aged 18-65 years (CI: 16.3 to 29.6) and 35.7% in elderly people aged over 65 years (CI: 29.5 to 42.0). Prevalence increased with age and was higher in females [30% (CI: 22 to 38)] compared to males [13% (CI: 9 to 17)]. Potential sources of bias were sampling method, study quality and method of HV diagnosis. Conclusions Notwithstanding the wide variation in estimates, it is evident that HV is prevalent; more so in females and with increasing age. Methodological quality issues need to be addressed in interpreting reports in the literature and in future research.

The bacterial component of the human gut microbiota undergoes a definable program of postnatal development. Evidence is accumulating that this program is disrupted in children with severe acute malnutrition (SAM) and that their persistent gut microbiota immaturity, which is not durably repaired with current ready-to-use therapeutic food (RUTF) interventions, is causally related to disease pathogenesis. To further characterize gut microbial community development in healthy versus malnourished infants/children, we performed a time-series metagenomic study of DNA isolated from virus-like particles (VLPs) recovered from fecal samples collected during the first 30 mo of postnatal life from eight pairs of mono- and dizygotic Malawian twins concordant for healthy growth and 12 twin pairs discordant for SAM. Both members of discordant pairs were sampled just before, during, and after treatment with a peanut-based RUTF. Using Random Forests and a dataset of 17,676 viral contigs assembled from shotgun sequencing reads of VLP DNAs, we identified viruses that distinguish different stages in the assembly of the gut microbiota in the concordant healthy twin pairs. This developmental program is impaired in both members of SAM discordant pairs and not repaired with RUTF. Phage plus members of the Anelloviridae and Circoviridae families of eukaryotic viruses discriminate discordant from concordant healthy pairs. These results disclose that apparently healthy cotwins in discordant pairs have viromes associated with, although not necessarily mediators, of SAM; as such, they provide a human model for delineating normal versus perturbed postnatal acquisition and retention of the gut microbiota’s viral component in populations at risk for malnutrition.

The androgen receptor (AR) is a key regulator of prostate growth and the principal drug target for the treatment of prostate cancer. Previous studies have mapped AR targets and identified some candidates which may contribute to cancer progression, but did not characterize AR biology in an integrated manner. In this study, we took an interdisciplinary approach, integrating detailed genomic studies with metabolomic profiling and identify an anabolic transcriptional network involving AR as the core regulator. Restricting flux through anabolic pathways is an attractive approach to deprive tumours of the building blocks needed to sustain tumour growth. Therefore, we searched for targets of the AR that may contribute to these anabolic processes and could be amenable to therapeutic intervention by virtue of differential expression in prostate tumours. This highlighted calcium/calmodulin‐dependent protein kinase kinase 2, which we show is overexpressed in prostate cancer and regulates cancer cell growth via its unexpected role as a hormone‐dependent modulator of anabolic metabolism. In conclusion, it is possible to progress from transcriptional studies to a promising therapeutic target by taking an unbiased interdisciplinary approach. Using a combination of genomic and metabolomic profiling strategies, the CAMKK2 kinase is identified as a critical downstream target of the androgen receptor. CAMKK2 regulates anabolic flux, and represents an attractive therapeutic target for prostate cancer treatments.

Introduction Patients undergoing laparotomy for emergency general surgery (EGS) conditions, constitute a high-risk group with poor outcomes. These patients have a high prevalence of comorbidities. This study aims to identify patient factors, physiological and time-related factors, which place patients into a group at increased risk of mortality. Methodology In a retrospective analysis of all patients undergoing an emergency laparotomy at Greys Hospital from December 2012 to 2018, we used decision tree discrimination to identify high-risk groups. Results Our cohort included 1461 patients undergoing a laparotomy for an EGS condition. The mortality rate was 12.4% (181). Nine hundred and ten patients (62.3%) had at least one known comorbidity on admission. There was a higher rate of comorbidities among those that died (154; 85.1%). Patient factors found to be associated with mortality were the age of 46 years or greater ( p < 0.001), current tuberculosis ( p < 0.001), hypertension ( p  = 0.014), at least one comorbidity (0.006), and malignancy (0.033). Significant physiological risk factors for mortality were base excess less than −6.8 mmol/L ( p < 0.001), serum urea greater than 7.0 mmol/L ( p < 0.001) and waiting time from admission to operation ( p  = 0.014). In patients with an enteric breach, those younger than 46 years and a Shock Index of more than 1.0 were high-risk. Patients without an enteric breach were high-risk if operative duration exceeded 90 min ( p  = 0.004) and serum urea exceeding 7 mmol/dl ( p  = 0.016). Conclusion In EGS patients, patient factors as well as physiological factors place patients into a high-risk group. Identifying a high-risk group should prompt consideration for an adjusted approach that ameliorates outcomes.

Background Despite the human immunodeficiency virus (HIV) being the most common comorbidity in South African surgical patients, its impact on appendicitis has not been well-described. We aimed to determine HIV status’ influence on patients’ presentation, assessment, management and outcomes with acute appendicitis. Methods The retrospective chart review included all patients aged 12 years and older who were HIV-positive or HIV-negative and presented with acute appendicitis between 1 January 2013 and 31 December 2019. The primary outcome measure was survival to discharge. Secondary outcomes included analysis of the presentation (vital signs), assessment (biochemical, inflammatory markers) and management (intraoperative anatomical severity grading, length of hospital stay). Results Of the 1096 patients with appendicitis, 196 (17.9%) were HIV-positive, and CD4 counts were available for 159. The median age was 23 years, with the HIV-positive patients being older and HIV-negative group having more males (58.7%). While the HIV-positive patients had a longer median length of hospital stay, there was no statistically significant difference in the two groups’ incidence of high-grade appendicitis ( p  = 0.670). The HIV-positive patients had a higher median shock index (OR 7.65; 95% [CI 2.042–28.64]) than their HIV-negative counterparts. HIV-positivity had a significant association with mortality (OR 9.56; 95% CI [1.68–179.39]), and of the seven HIV-positive patients who died, 66.7% ( n  = 4) had a CD4 < 200 cells/mm 3 (OR 8.6; 95% CI [1.6–63.9]). Conclusion HIV-positive patients, those with CD4 < 200 cells/mm 3 or not on ART, have increased mortality risk and may benefit from increased perioperative surveillance. Patients with an unknown HIV status in a high-prevalence population should be offered HIV testing to risk stratify more accurately.

Introduction This project aims to define the common comorbidities associated with patients undergoing emergency laparotomy in South Africa, to review the impact of these comorbidities on outcome and to attempt to model these various factors. Method A retrospective review of all patients undergoing emergency laparotomy for an emergency general surgical condition was performed from the prospectively entered Hybrid Electronic Medical Registry (HEMR). Univariate and multiple logistic regression analysis was performed to establish associations and independent risk factors for developing an adverse event. Results Over a six-year time period, a total of 1464 patients underwent emergency laparotomy. The median age was 34 years. Males constituted 58.8% (861) of the patients and 754 patients (51.5%) experienced at least one adverse event. The mortality rate was 12 percent. Comorbidities and social factors were documented in 912 patients (62.3%). The rate of adverse events among patients with comorbidities was 59% (538). Patients without comorbidities or significant social factors had an adverse event rate of 39.1% (216). This difference was statistically significant (p < 0.001). The most frequent comorbidity in our sample was HIV, followed by hypertension, underlying malignancy, diabetes mellitus, active TB and cardiovascular disease. Conclusion Emergency laparotomy in South Africa is associated with significant morbidity and mortality. The patients are younger than in high-income countries. Diabetes mellitus, hypertension, HIV and active TB are associated with the development of an AE.