MiniBioReactor Array (MBRA) in vitro gut model: a reliable system to study microbiota-dependent response to antibiotic treatment.

Background: Antimicrobial drugs are mostly studied for their impact on emergence of bacterial antibiotic resistance, but their impact on the gut microbiota is also of tremendous interest. In vitro gut models are important tools to study such complex drug-microbiota interactions in humans. Methods: The MiniBioReactor Array (MBRA) in vitro microbiota system; a single-stage continuous flow culture model, hosted in an anaerobic chamber; was used to evaluate the impact of three concentrations of a third-generation cephalosporin (ceftriaxone) on faecal microbiota from two healthy donors (treatment versus control: three replicates per condition). We conducted 16S microbiome profiling and analysed microbial richness, diversity and taxonomic changes. ß-Lactamase activities were evaluated and correlated with the effects observed in the MBRA in vitro system. Results: The MBRA preserved each donor's specificities, and differences between the donors were maintained through time. Before treatment, all faecal cultures belonging to the same donor were comparable in composition, richness, and diversity. Treatment with ceftriaxone was associated with a decrease in α-diversity, and an increase in ß-diversity index, in a concentration-dependent manner. The maximum effect on diversity was observed after 72 h of treatment. Importantly, one donor had a stronger microbiota ß-lactamase activity that was associated with a reduced impact of ceftriaxone on microbiota composition. Conclusions: MBRA can reliably mimic the intestinal microbiota and its modifications under antibiotic selective pressure. The impact of the treatment was donor- and concentration-dependent. We hypothesize these results could be explained, at least in part, by the differences in ß-lactamase activity of the microbiota itself. Our results support the relevance and promise of the MBRA system to study drug-microbiota interactions.

Suction drainage fluid culture during septic orthopaedic surgery, a retrospective study.

We evaluated the usefulness of suction drainage fluid culture after septic orthopaedic surgery to predict early surgical reintervention. We conducted a retrospective observational study, at the Groupe Hospitalier Paris Saint-Joseph between 2014 and 2019. All the patients undergoing septic orthopaedic surgery, with perioperative samples and a postoperative suction drainage device, were enrolled. We compared the group with positive or negative postoperative drainage fluid cultures, respectively, on surgical outcome. We included 246 patients. The drainage fluid culture was positive in 42.3% of the cases. Early surgical reintervention concerned 14.6% of the cases (n = 36), including 61.1% of patients with positive drainage fluid culture (n = 22/36). The risk factors associated with positive drainage fluid cultures were the debridement of the infected site (without orthopaedic device removal), an infection located at the spine, perioperative positive cultures to Staphylococcus aureus. The complete change of the orthopaedic device, and coagulase-negative staphylococci on the preoperative samples, was associated with negative drainage fluid cultures. Positive drainage fluid culture was predictive of early surgical reintervention, and coagulase-negative staphylococci in the preoperative samples and knee infection were predictive of surgical success. Postoperative drainage fluid cultures were predictive of early surgical reintervention. Randomized multicentric studies should be further conducted.

Combined Atomic Force Microscope and Volumetric Light Sheet System for Correlative Force and Fluorescence Mechanobiology Studies.

The central goals of mechanobiology are to understand how cells generate force and how they respond to environmental mechanical stimuli. A full picture of these processes requires high-resolution, volumetric imaging with time-correlated force measurements. Here we present an instrument that combines an open-top, single-objective light sheet fluorescence microscope with an atomic force microscope (AFM), providing simultaneous volumetric imaging with high spatiotemporal resolution and high dynamic range force capability (10 pN - 100 nN). With this system we have captured lysosome trafficking, vimentin nuclear caging, and actin dynamics on the order of one second per single-cell volume. To showcase the unique advantages of combining Line Bessel light sheet imaging with AFM, we measured the forces exerted by a macrophage during FcɣR-mediated phagocytosis while performing both sequential two-color, fixed plane and volumetric imaging of F-actin. This unique instrument allows for a myriad of novel studies investigating the coupling of cellular dynamics and mechanical forces.

A preliminary prospective study: Could the labeling of a health-care message on a consumer product limit forgetfulness in parents confronted with immunization?

BACKGROUND: Parental hesitancy in immunization is an emerging and concerning problem owing to the serious consequences of a lack of vaccination. Few tools are available to combat this phenomenon. AIMS: To evaluate the interest of parents in recording the vaccine schedule on a common consumer product as a solution to prevent immunization oversight. METHOD: We conducted a preliminary prospective and monocentric study, in a parental population, using surveys to evaluate interest in this solution, and to define the sociodemographic characteristics of our population. Our population was clustered into three groups: against immunization, hesitant/negligent, and pro-immunization. This solution was evaluated using a univariate model between fearful and confident populations in respect of immunization, associated with a descriptive analysis of the population against immunization. RESULTS: Of 825 surveys distributed, 709 were analyzed. There were 47 parents against immunization (6.6%), 284 hesitant/negligent parents (40%), and 378 pro-immunization parents (53.3%). We showed that the hesitant/negligent population reported more difficulties in remembering the immunization schedule (P<0.001; OR=0.36; 95% CI [0.25-0.51]), and was interested in discussions on immunization (P<0.001; OR=0.41; 95% CI [0.29-0.58]). This population prone to oversight was interested in the labeling of an everyday consumer product with the immunization schedule (P=0.03; OR=0.68; 95% CI [1.02-2.11]) to limit the number of missed injections. CONCLUSION: There is no single or perfect solution to combat the current anti-immunization problem, although communication through everyday consumer products seems to be an interesting tool for raising parental awareness of the importance of immunization. Further studies are required to evaluate the effectiveness of this tool.

Detection of Bartonella in cat scratch disease using a single-step PCR assay kit.

PURPOSE: Bartonella is an increasingly isolated emerging pathogen that can cause severe illness in humans, including cat scratch disease (CSD). The bacteria are difficult to grow and thus many detection methods have been developed, especially molecular. We previously developed a PCR method targeting ribC to identify Bartonella sp. A manufactured kit (RealCycler BART, Progenie Molecular) was commercialised shortly thereafter for the detection of Bartonella infection, including Bartonella henselae. METHODOLOGY: We performed a comparison between this test and our in-house PCR assay on 73 lymphadenopathy samples sent to the laboratory for suspicion of CSD.Results/Key findings. Among the 28 positive samples for Bartonella, 21 were identified by the two PCR assays, and seven by the commercial kit only. CONCLUSION: The performance of this commercial kit suggests that it could be a suitable alternative to our in-house PCR assay, highlighting the importance of the molecular methods used to diagnose CSD.

A Rare Complication of Central Venous Catheter Extravasation in a Preterm Neonate: Hemidiaphragmatic Paralysis.

We report a case of a preterm neonate born at 26 weeks' of gestation diagnosed with unilateral diaphragmatic paralysis. This paralysis was a consequence of a phrenic nerve injury due to extravasation of hyperosmolar parenteral nutrition fluid in the upper thorax. Chest X-rays and ultrasonography confirmed the diagnosis. The neonate was treated with prolonged respiratory support and did not require surgical treatment. This report describes a case of hemidiaphragmatic paralysis as a complication of central venous catheter insertion. In neonates, spontaneous recovery of diaphragmatic paralysis is possible. This study concludes that recovery of extravasation injury-induced phrenic nerve palsy in the context of conservative management is possible.

Acute kidney injury in major gynaecological surgery: an observational study.

OBJECTIVE: To assess the prevalence, outcomes and cost associated with acute kidney injury (AKI) defined by consensus risk, injury, failure, loss, and end-stage kidney (RIFLE) criteria after gynaecologic surgery. DESIGN: Retrospective single-centre cohort study. SETTING: Academic medical centre. SAMPLE: Two thousand three hundred and forty-one adult women undergoing major inpatient gynaecologic surgery between January 2000 and November 2010. METHODS: AKI was defined by RIFLE criteria as an increase in serum creatinine greater than or equal to 50% from the reference creatinine. We used multivariable regression analyses to determine the association between perioperative factors, AKI, mortality and cost. MAIN OUTCOME MEASURES: AKI, combined major adverse events (hospital mortality, sepsis or mechanical ventilation), 90-day mortality and hospital cost. RESULTS: Overall prevalence of AKI was 13%. The prevalence of AKI was associated with the primary diagnosis. Of women with benign tumour surgeries, 5% (43/801) experienced AKI compared with 18% (211/1159) of women with malignant disease (P < 0.001). Only 1.3% of the whole cohort had evidence of urologic mechanical injury. In a multivariable logistic regression analysis, AKI patients had nine times the odds of a major adverse event compared to patients without AKI (adjusted odds ratio 8.95, 95% confidence interval 5.27-15.22). We have identified several readily available perioperative factors that can be used to identify patients at high risk for AKI after in-hospital gynaecologic surgery. CONCLUSIONS: AKI is a common complication after major inpatient gynaecologic surgery associated with an increase in resource utilisation and hospital cost, morbidity and mortality.

Elevated arsenic and manganese in groundwaters of Murshidabad, West Bengal, India.

High levels of geogenic arsenic (As) and manganese (Mn) in drinking water has led to widespread health problems for the population of West Bengal, India. Here we delineate the extent of occurrences of As and Mn in Murshidabad, where the contaminated aquifers occur at shallow depths between 35 and 40 m and where access to safe drinking water is a critical issue for the local population. A total of 78 well-water samples were taken in 4 blocks on either side of the river Bhagirathi: Nabagram and Kandi (west, Pleistocene sediments), Hariharpara and Beldanga (east, Holocene sediments). High As, total iron (FeT) and low Mn concentrations were found in waters from the Holocene gray sediment aquifers east of the river Bhagirathi, while the opposite was found in the Pleistocene reddish-brown aquifer west of the river Bhagirathi in Murshidabad. Speciation of As in water samples from Holocene sediments revealed the dominant species to be As(III), with ratios of As(III):AsT ranging from 0.55 to 0.98 (average 0.74). There were indications from saturation index estimations that Mn solubility is limited by the precipitation of MnCO3. Tubewells from high As areas in proximity to anthropogenic waste influx sources showing high molar Cl/Br ratios, low SO4(2-) and low NO3(-) demonstrate relatively lower As concentrations, thereby reducing As pollution in those wells. Analyses of core samples (2 in each of the blocks) drilled to a depth of 45 m indicate that there is no significant variation in bulk As (5-20mg/kg) between the Holocene and Pleistocene sediments, indicating that favorable subsurface redox conditions conducive to mobilization are responsible for the release of As. The same applies to Mn, but concentrations vary more widely (20-2000 mg/kg). Sequential extraction of Holocene sediments showed As to be associated with 'specifically sorbed-phosphate-extractable' phases (10-15%) and with 'amorphous and well crystalline Fe-oxyhydroxide' phases (around 37%) at As-contaminated well depths, suggesting that the main As release mechanisms could be either competitive ion exchange with PO4(3-), or the dissolution of Fe oxyhydroxides. In the Pleistocene sediments Mn is predominantly found in the easily exchangeable fraction.

Effect of aluminium filtration on dose and image quality in paediatric slot-scanning radiography.

This paper examines the effect that a 1.8 mm aluminium filter has on paediatric patient dose and image quality for linear slot scanning radiography (LSSR). A dynamic dose prediction model for LSSR accurately predicted the dose reduction effects of added aluminium filtration. A cadaver imaging study was carried out to assess the effects of filtration on image quality. With 1.8 mm added aluminium filtration, no visible degradation to image contrast or clarity was found, and in some cases the aluminium filtration improved the image quality as judged by radiologists.

A framework for redesigning or fine-tuning your benefit package--results from a national survey of stressful life events.

The results of a national survey of stressful life events are introduced as a useful framework for redesigning or fine-tuning corporate benefit packages to better meet employee needs, as well as to attract and retain top talent. Among the specific recommendations are (a) expanded bereavement leave, (b) hospice services, (c) employee assistance program access, (d) child care/elder care and (e) group legal services. Offering benefits that enable individuals to cope more effectively with major life event stressors is viewed as a powerful way of strengthening the psychological contract between employee and employer.

Large sample validations of three general predictors of pilot training success.

This article addresses one of the perennial problems of pilot selection research: obtaining an adequate sample size for reliable statistical analysis of predictive validity. Results from three studies involving the same computerized tests of instrument comprehension and psychomotor ability were combined in a meta-analysis to determine whether the validities of these tests generalized across three contexts. These were Royal Air Force and Turkish Air Force fixed-wing pilot training and British Army Air Corps rotary-wing pilot training. In this article, we discuss the adequacy of samples for estimating the validity of the tests, and the persistence of predictive validity to later stages of training as shown by British Army Air Corps data. Reference is also made to data from a fourth independent study of Qantas pilot training.

Impairment of vascular endothelial function by high-potassium storage solutions.

High-potassium cold storage solutions are currently used to preserve myocardial function during heart transplantation. However, the effects of high potassium concentration on vascular endothelial function are not well known. We therefore tested vascular rings for endothelial-dependent and endothelial-independent relaxation during storage in normokalemic, normothermic buffers and then in buffers supplemented with 10 to 110 mmol/L KCl. Maximal endothelial-dependent relaxation was significantly reduced at all high potassium concentrations. Endothelial-independent relaxation was impaired only with 80 and 110 mmol/L KCl buffers. Both endothelial-dependent relaxation and endothelial-independent relaxation returned to normal values after washout of excess potassium. Similarly, endothelial-dependent relaxation and endothelial-independent relaxation were assessed in rings after 24 hours of hypothermic storage in normokalemic Krebs buffer, and in buffers containing 20 and 110 mmol/L KCl. Maximal endothelial-dependent relaxation was significantly reduced after preservation in the high-potassium solutions, whereas endothelial-independent relaxation was not impaired. We conclude that there is significant impairment of endothelial function after cold storage in a high-potassium buffer. Inadequate washout of potassium during normothermic conditions may lead to further functional impairment of vascular responsiveness. A low-potassium storage medium is recommended for improved vascular protection.

The assessment center: evaluating managerial potential.

This assessment center helps unit directors critique their own managerial strengths and weaknesses and formulate effective self-improvement plans and growth strategies. Structured activities also provide a framework for administrators to identify managerial talent and to develop potential nurse managers effectively.

Measurement of body surface topography using an automated imaging system.

An automatic computer imaging system for recording body surface topography has been developed on a microcomputer-based image processing system. The computer processes fringe patterns generated on the surface of the trunk and reconstructs the complete 3-dimensional form of the surface. From the topographic reconstruction, clinical parameters of scoliotic deformity such as Angle of Trunk Inclination are calculated at a number of levels from the upper thoracic to the sacral region. These multiple level measurements illustrate the change in deformity over the trunk and correspond to measurements obtained using conventional tactile devices on patients.

Denervation of transplanted porcine lung causes airway obstruction.

Lung transplantation can be complicated by a form of small airway obstruction known as bronchiolitis obliterans. We tested the hypothesis that lung denervation causes small airway obstruction in young pigs (10 +/- 1 weeks). Control pigs had an innervated native lobe, and study pigs had either a denervated native lobe or a denervated transplant lobe. Transplanted pigs received standard immunosuppression. At 10 weeks we measured isolated left lobe pulmonary mechanics. Dynamic resistance in both study groups was significantly higher than in the lobectomy group, whereas dynamic compliance in both study groups was significantly lower than in the lobectomy group. No significant difference in resistance or compliance was noted between the transplant and reimplant groups. Histologic changes consistent with rejection were noted in the transplant lobes. We conclude that the small airway obstruction noted in this model is due to operative denervation rather than to immunosuppression or rejection.

The influence of preoperative shock on outcome in sequential endocardial resection for ventricular tachycardia.

Sequential endocardial resection was used in 92 consecutive patients to treat ventricular tachycardia. All patients had coronary artery disease with previous myocardial infarction. All patients had repeated cycles of mapping and resection of arrhythmogenic foci in the normothermic beating heart until ventricular tachycardia was no longer inducible. Eighty-six patients (93%) survived to hospital discharge. The survival rate in patients normotensive at the time of operation was 98% and in patients in shock at the time of operation, 43%. By Cox regression analysis, preoperative shock was the significant predictor (p less than 0.001) of operative mortality. Seventy-four of the 86 operative survivors (86%) had no sustained ventricular tachycardia at initial postoperative electrophysiologic study when receiving no antiarrhythmic drugs. Eighty-three of the 86 operative survivors (97%) had no sustained ventricular tachycardia at final postoperative electrophysiologic study when using antiarrhythmic drugs as needed. After a median follow-up of 21 months (range 1 to 79 months) there were 4 sudden cardiac deaths, 12 other cardiac deaths, and 3 noncardiac deaths. There were no documented nonfatal episodes of sustained monomorphic ventricular tachycardia after hospital discharge. Use of the sequential endocardial resection technique is effective in curing ventricular tachycardia with low operative morbidity and mortality.

Autoimmune enteropathy and nephropathy with circulating anti-epithelial cell antibodies.

We describe a child with circulating anti-epithelial cell antibodies, autoimmune enteropathy with intestinal villous atrophy, and membranous glomerulonephritis. The patient had persistent diarrhea at 6 months of age, and a small bowel biopsy showed active enteritis, villous atrophy, and crypt hyperplasia. When the patient was, 10 months of age, nephrotic syndrome developed because of membranous glomerulonephritis. Results of tests for circulating immune complexes were negative. Indirect immunofluorescence studies revealed a circulating antibody directed against renal epithelial cells. Circulating antibodies directed against normal small intestine epithelial cells were also detected by the immunoperoxidase technique. Western blot and immunoprecipitation identified a 55-kd antigen, in both small bowel and kidney, that reacted with an antibody in the patient's serum. High-dose prednisone therapy induced a clinical remission, resolution of the small bowel injury, and diminished serum anti-epithelial cell antibodies; after dose reduction, clinical relapse occurred with villous atrophy and reappearance of anti-epithelial cell antibodies. When the patient was 45 months of age, persistent diarrhea recurred despite intravenous administration of corticosteroids, cyclosporine, and total parenteral nutrition. Autoantibodies to a 55-kd epithelial cell protein are temporally related to the development of enteropathy and nephropathy. Study of similar patients is needed to determine the role of such antibodies in this disorder.