Comparison of CyTOF assays across sites: Results of a six-center pilot study.

For more than five years, high-dimensional mass cytometry has been employed to study immunology. However, these studies have typically been performed in one laboratory on one or few instruments. We present the results of a six-center study using healthy control human peripheral blood mononuclear cells (PBMCs) and commercially available reagents to test the intra-site and inter-site variation of mass cytometers and operators. We used prestained controls generated by the primary center as a reference to compare against samples stained at each individual center. Data were analyzed at the primary center, including investigating the effects of two normalization methods. All six sites performed similarly, with CVs for both Frequency of Parent and median signal intensity (MSI) values<30%. Increased background was seen when using the premixed antibody cocktail aliquots at each site, suggesting that cocktails are best made fresh. Both normalization methods tested performed adequately for normalizing MSI values between centers. Clustering algorithms revealed slight differences between the prestained and the sites-stained samples, due mostly to the increased background of a few antibodies. Therefore, we believe that multicenter mass cytometry assays are feasible

The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set

Background Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. Methods Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. Results Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). Conclusions The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy

Effects of calcitonin on plasma calcium and phosphate in the mudskipper, Periophthalmodon schlosseri (Teleostei), in water and during exposure to air

General and Comparative Endocrinology702224-230GCEN

Studies on the effect of air exposure on gill Na+/K+-ATPase of the marble goby, Oxyeleotris marmorata, a facultative air-breathing fish

10.1007/BF01875700Fish Physiology and Biochemistry53121-130FPBI

Duration of infection and strain variation in Streptococcus uberis isolated from cows' milk

The duration of infection and pulsed-field gel electrophoresis (PFGE) types of bovine intramammary Streptococcus uberis isolates were examined. Milk samples were collected in duplicate from all 4 glands of 503 cows from 5 herds within 1 to 3 d of parturition and from 113 cows with clinical mastitis in the same herds throughout lactation. Glands from which S. uberis was isolated were resampled at 28-d intervals. The prevalence of S. uberis was 12% for cows around parturition, and the median duration of infection was 16 d. Cows >2 yr old had a longer duration of infection than 2 yr old cows, and duration varied among herds. A total of 173 different PFGE types were identified from a total of 234 S. uberis isolates. Each farm had a unique set of PFGE types. Only 3 PFGE types were common to each of 3 pairs of cows, and these occurred on the same farm. Where S. uberis was isolated on more than one occasion from a gland, only 55% of the PFGE types were the same across time. For cows with multiple glands infected, only one-half (9 of 18) had the same PFGE type in more than one gland. No predominant PFGE type was identified in any herd. It is concluded that there was wide heterogeneity of PFGE types, that the environment rather than other cows was the likely source of S. uberis infections, and that glands may be infected with multiple S. uberis PFGE types over a lactation

Comparing production-biomass ratios of benthos and suprabenthos in macrofaunal marine crustaceans

Using available data from the literature, we compared the productionbiomass ratios (P/B) between the suprabenthic (= hyperbenthic) and the benthic (infaunaepifauna) species within the group of the macrofaunal marine crustaceans. This data set consists of 91 P/B estimates (26 for suprabenthos and 65 for infaunaepifauna) for 49 different species. Suprabenthic crustacean P/B was significantly higher than P/B of benthic crustacean (post-hoc Scheffé test; one-way analysis of covariance, ANCOVA; p < 103) and also of other (noncrustacean) benthic invertebrate (p < 104). Predictive multilinear regression (MLR) analysis for macrofaunal marine crustaceans showed P/B to depend significantly on mean annual temperature (T) and mean individual weight (W) (R2 = 0.367). Adding the variable swimming capacity increased goodness-of-fit to R2 = 0.528. The higher P/B of suprabenthic (= swimming) macrofauna in comparison with that of the benthic compartment seems to be related to the most apparent feature of the suprabenthos, its swimming capacity. The high P/Bs reported for suprabenthic species indicate how a nontrivial part of benthic production can be ignored if suprabenthos is not well sampled, therefore biasing the models of energy flow generated for trophic webs