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Aim: The gastrointestinal bile acid (BA)/microbiota axis has emerged as a potential mediator of health and disease, particularly in relation to pathologies such as inflammatory bowel disease (IBD) and colorectal cancer. Whilst it presents an exciting new avenue for therapies, it has not yet been characterized in surgical resection of the ileum, where BA reabsorption occurs. The identification of BA/microbiota signatures may provide future therapies with perioperative personalized medicine. In this work we conduct a systematic review with the aim of investigating the microbiome and BA changes that are associated with resection of the ileum. Method: The databases included were MEDLINE, EMBASE, Web of Science and Cochrane libraries. The outcomes of interest were faecal microbiome and BA signatures after ileal resection. Results: Of the initial 3106 articles, three studies met the inclusion/exclusion criteria for data extraction. A total of 257 patients (46% surgery, 54% nonsurgery controls) were included in the three studies. Two studies included patients with short bowel syndrome and the other included patients with IBD. Large‐scale microbiota changes were reported. In general, alpha diversity had decreased amongst patients with ileal surgery. Phylum‐level changes included decreased Bacteroidetes and increased Proteobacteria and Fusobacteria in patients with an intestinal resection. Surgery was associated with increased total faecal BAs, cholic acid and chenodeoxycholic acid. There were decreases in deoxycholic acid and glycine and taurine conjugated bile salts. Integrated BA and microbiota data identified correlations with several bacterial families and BA. Conclusion: The BA/microbiota axis is still a novel area with minimal observational data in surgery. Further mechanistic research is necessary to further explore this and identify its role in improving perioperative outcomes. [ABSTRACT FROM AUTHOR]

Background The application of antiseptic skin agents prior to incision minimizes the rate of surgical site infection. Despite their ubiquity, the optimal skin preparation agent remains uncertain. A retrospective economic analysis was conducted to complement the results from the NEWSkin Prep trial which prospectively compared three preparation agents. Methods A cost and cost-effectiveness analysis was performed from a healthcare service perspective to compare chlorhexidine with 70% ethanol, and aqueous povidone-iodine, against povidone-iodine with 70% ethanol. Resource use estimates accounted for hospital admissions, readmissions associated with surgical site infection, outpatient and general practitioner attendances, visits from community nurses and therapeutic consumables. The measure of effectiveness comprised the net difference in number of patients with surgical site infections per 1000 patients. Costs were compared using a two-sample Welch's t -test. Deterministic and probabilistic sensitivity analyses were performed to evaluate the incremental cost-effectiveness ratio. Results The null hypothesis that the mean costs for the trial arms were significantly different was not rejected (Welch's t -test P value: 0.771 for chlorhexidine with 70% ethanol against povidone-iodine with 70% ethanol; and 0.955 for aqueous povidone-iodine against povidone-iodine with 70% ethanol). Based on bootstrap averages, the chlorhexidine with 70% ethanol intervention generated 8.0 fewer surgical site infections per 1000 patients and net cost savings of €151,698 (Euros) per 1000 patients compared with povidone-iodine with 70% ethanol, and aqueous povidone-iodine produced a net cost saving of €37,494 per 1000 patients but generated an additional 11.6 surgical site infections per 1000 patients compared with povidone-iodine with 70% ethanol. The comparison of chlorhexidine with 70% ethanol to povidone-iodine with 70% ethanol was sensitive to the inclusion of cost outliers, while the comparison of aqueous povidone-iodine to povidone-iodine with 70% ethanol was sensitive to the estimated cost per surgical site infection. Conclusion Based on the outcomes from the NEWSkin Prep study, this economic analysis found no definitive evidence in favour of any one of the study comparators. Future model-based economic analyses of alternative skin preparations should critically address the quality of evidence and integrate the results from the NEWSkin Prep study. [ABSTRACT FROM AUTHOR]

Background: Surgical Site Infection (SSI) of the abdominal incision is a dreaded complication following colorectal surgery. Identifying the intraoperative surgical site microbes may provide clarity in the pathogenesis of SSIs. Genomic sequencing has revolutionized the ability to identify microbes from clinical samples. Utilization of 16S rRNA amplicon sequencing to characterize the intraoperative surgical site may provide the critical information required to predict and prevent infection in colorectal surgery. Methods: This is a pilot, prospective observational study of 50 patients undergoing elective colorectal resection. At completion of surgery, prior to skin closure, swabs were taken from the subcutaneous tissue of the abdominal incision to investigate the microbial profile. Dual swabs were taken to compare standard culture technique and 16S rRNA sequencing to establish if a microbial profile was associated with postoperative SSI. Results: 8/50 patients developed an SSI, which was more likely in those undergoing open surgery (5/15 33.3% versus 3/35, 8.6%; P = 0.029). 16S rRNA amplicon sequencing was more sensitive in microbial detection compared to traditional culture. Both culture and 16S rRNA demonstrated contamination of the surgical site, predominantly with anaerobes. Culture was not statistically predictive of infection. 16S rRNA amplicon sequencing was not statistically predictive of infection, however, it demonstrated patients with an SSI had an increased biodiversity (not significant) and a greater relative abundance (not significant) of pathogens such as Bacteroidacaea and Enterobacteriaceae within the intraoperative site. Conclusions: 16S rRNA amplicon sequencing has demonstrated a potential difference in the intraoperative microbial profile of those that develop an infection. These findings require validation through powered experiments to determine the overall clinical significance. [ABSTRACT FROM AUTHOR]

Enzymes are used extensively as industrial bio-catalysts in various manufacturing and processing sectors. However, commercial enzymes are expensive in part due to the high cost of the nutrient medium for the biomass culture. Activated sludge (AS) is a waste product of biological wastewater treatment and consists of microbial biomass that degrades organic matter by producing substantial quantities of hydrolytic enzymes. Recovering enzymes from AS therefore offers a potential alternative to conventional production techniques. A carrier-free, cross-linked enzyme aggregate (CLEA) was produced from crude AS enzyme extract for the first time. A major advantage of the CLEA is the combined immobilization, purification, and stabilization of the crude enzymes into a single step, thereby avoiding large amounts of inert carriers in the final enzyme product. The AS CLEA contained a variety of hydrolytic enzymes and demonstrated high potential for the bio-conversion of complex organic substrates. [ABSTRACT FROM AUTHOR]

The virtual patient is a case-based computer program that combines textual information with multimedia elements such as audio, graphics, and animation. It is increasingly being utilized as a teaching modality by medical educators in various fields of instruction. The inherent complexity of older patients and the shortage of geriatrics educators have spurred the development of virtual patient programs to teach geriatrics at the medical undergraduate, graduate, and postgraduate levels. As an instructional tool, the Virtual Patient must be placed in the correct educational context to help educators identify opportunities for its proper use in the curriculum. In this review, the experiences of three medical schools in the development and application of geriatric virtual patients are described as case studies. In each case study, the challenges encountered and solutions developed are presented. Areas of future research in the use of virtual patients in geriatrics education include the determination of the optimal combination of features, the settings of use of virtual patient programs, the underlying pedagogy, and the limitations in its application in clinical instruction. (Contains 3 tables.)

Describes a new competency-based curriculum and discusses the planning, structure, and implementation of this curriculum at Brown University School of Medicine. (Author/CCM)

Background: Sarcopenia has been shown to have significant adverse health outcomes in a range of patient populations. Particularly, sarcopenic patients having cancer surgery are a unique group who demonstrate poorer post‐operative outcomes. Currently, the gold standard in diagnosing sarcopenia is through the use of computed tomography. However, the widespread use of imaging to diagnose patients with sarcopenia is neither cost‐effective nor practical. Identifying a serum biomarker or a simple mobility scoring system as an alternative diagnostic tool may aid in identifying more patients at risk of sarcopenia. C1q, a novel biomarker, has previously been shown to correlate with sarcopenia. Similarly, we sought to explore whether mobility scores may provide a useful surrogate marker for sarcopenia. Methods: This was a prospective cohort study of patients who presented for colorectal cancer surgery between the dates of 6/10/2016 and 4/10/2017 at John Hunter Hospital. Computed tomography was utilized to calculate the psoas area at the L3 spinal level. Pre‐operative blood samples were obtained for C1q analysis and de Morton Mobility Index (DEMMI) was also performed. Results: A total of 51 patients were included in the study. The median age of the patients were 69 years old. We did not demonstrate a correlation between serum C1q and DEMMI scores with psoas area. Conclusion: Our findings suggest that neither C1q nor DEMMI scores are correlated with psoas area in a colorectal cancer population. [ABSTRACT FROM AUTHOR]

Background: Preoperative skin antiseptics are used prior to surgery to reduce the risk of surgical site infection (SSI). There is debate as to which is the most effective. The aim of this network meta‐analysis (NMA) is to compare the effectiveness of different skin preparations at reducing SSIs in patients undergoing incisional surgery. Methods: The study protocol was published in PROSPERO (CRD4202181599) a priori with predefined search terms and inclusion/exclusion criteria. The skin preparations for comparison were: chlorhexidine/alcohol (CHA), chlorhexidine/water (CHW), poviodine/alcohol (PVIA), poviodine/water (PVIW). The records identified were screened by two authors independently by title, abstract and in full text. The revised tool for risk‐of bias (ROB2) assessment was used. Results: Twenty‐nine RCTs involving 15 796 patients were included in the NMA. A significant but small increase in the odds of infection was seen in the PVIW group compared to the CHA group (OR 1.34, 95%CrI 1.09–1.64), but other comparisons were not statistically significantly different. Ranking the treatment arms showed there was a 64% probability that CHA is the most effective and a 62.7% probability that PVIW is the least effective treatment. Conclusion: Chlorhexidine/alcohol (CHA) was found to be the most effective for prevention of superficial and deep SSI while PVIW was the least. There was no differences seen between CHA and PVIA, or CHW and PVIW. The superiority of CHA is likely due to the effect of the alcohol in the base. Hence the choice between CHA and PVIA should be based on health and cost considerations. [ABSTRACT FROM AUTHOR]

Byline: Iakovos Skourides (Centre for Environmental Control and Waste Management, Department of Civil and Environmental Engineering, Imperial College London, UK); Stephen R. Smith (Centre for Environmental Control and Waste Management, [...]

Slow sand filtration (SSF) is widely used throughout the world for the treatment of drinking water. However, relatively little attention has been given to the development of a comprehensive process model. Previous studies have considered separate aspects of the SSF process, such as developing an improved representation of the schmutzdecke layer, and a more detailed description of the microbial dynamics. The objective of this work was to develop a deterministic simulation model of the SSF process incorporating fundamental physicochemical and biological dynamics within a classical filtration framework. The model was based on a temporal and spatial finite difference method and was calibrated and verified using operational data from pilot-scale SSF units. Results from the calibration showed that the model satisfactorily predicts headloss development in SSF units. There was no significant difference between many of the most sensitive model parameter values for two successive runs of the same filter. However, a few individual model parameters (e.g., in the fundamental headloss equations) were found to vary with filtration run and it is speculated that this is due to seasonal factors. CE Database subject headings: Simulation; Filtration; Biomass; Sand; Water treatment.

This paper describes the use of a deterministic slow sand filter process model to investigate and assess some of the fundamental aspects and mechanisms operating during slow sand filtration (SSF). These include the role of the schmutzdecke, biomass development, and the initial condition of the filter, to the overall process performance. The SSF process model has been developed recently and is described in a companion paper by Campos et al., in 2006. It attempts to provide a simulation of the physicochemical and biological processes responsible for the filtration mechanisms operating in SSF. The simulation of filter runs has been carried out with the help of extensive pilot plant data provided by Thames Water Utilities Ltd., involving both uncovered and covered filter beds. The results demonstrate that the presence and nature of a schmutzdecke layer profoundly influence the spatial and temporal development of interstitial biomass within the sand and, consequently, the headloss profile. Microbial interactions in the filter bed play a fundamental role in the process and are involved in setting the pattern and magnitude of headloss development. The model also demonstrates the significance of residual deposits within the filter after surface cleaning, on the subsequent filter behavior. CE Database subject headings: Simulation; Biomass; Sand; Water treatment; Models.

A study of 406 Brown University (Rhode Island) medical students found slightly over half had undergraduate majors in science or mathematics, a third majored in the humanities or social sciences, and a tenth had double majors or independent concentrations. No statistically significant difference was found between medical school performances of the first two groups. (MSE)