Juvenile rhesus monkeys have lower type 2 cytokine responses than adults after primary infection with Schistosoma mansoni

Adults and children have differences in their susceptibility to schistosomiasis. The relative influences of age-dependent innate resistance and acquired immunity in the differences between susceptibility to schistosomiasis are difficult to assess in humans. Therefore, we exposed juvenile and adult female rhesus monkeys to primary infection with Schistosoma mansoni. In contrast to the adult animals, the juvenile rhesus monkeys had low levels of interleukin (IL)-4 and IL-5 production by peripheral blood mononuclear cells after schistosome infection, as well as lower levels of parasite-antigen-specific antibody (IgG, IgM, and IgA) responses, and produced limited antigen-specific or total IgE. Juvenile animals had statistically nonsignificant increased worm burdens and tissue or fecal egg counts, compared with that of adults, whereas circulating schistosome antigens were significantly higher in infected juvenile monkeys. These results suggest that juvenile rhesus monkeys have reduced type 2 cytokine responses after primary schistosome infections and perhaps are more susceptible to parasite infection.     

Low acid output in Pima Indians

Duodenal ulcer has not been observed in full-heritage Pima Indians, while gastric cancer is relatively frequent. To investigate possible underlying factors for this phenomenon, we determined gastric acid output, gastric emptying rate, and plasma levels of gastrin, pepsinogen I, and pepsinogen II in apparently healthy Pima Indian and in Caucasian controls. The Pimas had significantly lower basal and stimulated outputs of gastric acid and higher fasting and postprandial plasma gastrin concentrations than the caucasians. Plasma pepsinogen I levels were similar in the two groups, but plasma pepsinogen II was significantly higher and the ratio of pepsinogen I to pepsinogen II was significantly lower in the Pima Indians. In addition, gastric emptying of an acaloric liqid meal was significantly delayed in the Pimas. The results suggest that the absence of duodenal ulcer in Pima Indians may be related to low gastric acid production and aslow rate of gastric emptying in this population. The associated findings of hypergastrinemia, hyperpepsinogenemia II, and a low ratio of pepsinogen I to pepsinogen II suggest that the hypochlorhydria may reflect an increased pervalence of chronic gastritis in full-heritage Pima Indians. This, in turn, could represent a risk factor for the development of gastric cancer in this population.Supported in part by research Contract 1-Am-6-2219 and grant AM 13233 from the National Institutes of Health, Bethesda, Maryland     

Inhibitory effect of intragastric glucose on gastric acid secretion and gastric emptying of liquids in man

Intragastric glucose inhibits gastric acid secretion and gastric emptying in man. To determine if these effects are mediated by somatostatin—a known inhibitor of gastric acid production, gastrin secretion, and gastric motility—the plasma somatostatin-like immunoreactivity (SLI) levels were determined in healthy human subjects after an intragastric load of 30% glucose solution. These findings were compared with results after an instillation of distilled water. Following the glucose load, the intragastric acid concentration, the acid output, and the fractional gastric emptying rate declined significantly (P<0.01) before either the plasma glucose or plasma insulin levels had increased. Neither the gastrin nor SLI plasma concentrations changed after the water or glucose load. These findings suggest that the suppression of gastric acid secretion and inhibition of the rate of gastric emptying that occur with intragastric glucose are mediated by factors other than changes in the peripheral circulating levels of SLI, gastrin, insulin, or glucose.     

Nanofiller-conjugated percolating conductive network modified polymerization reaction characteristics of aromatic thermosetting copolyester resin

Deliberately controlled interfacial interactions between incorporated nanofiller particles and host polymer backbone chains constitute a critical element in the realm of polymer nanocomposites with tailorable multifunctional properties. We demonstrate the physicochemical effects induced by graphene nanoplatelets (GNP) of different sizes on the condensation polymerization reaction of aromatic thermosetting copolyester (ATSP) through the formation of electrically conductive percolating networks as enabled by interfacial interactions. Carboxylic acid and acetoxy-capped precursor oligomers of ATSP are solid-state mixed with chemically pristine GNP particles at various loading levels. Upon in situ endothermic condensation polymerization reaction, crosslinked backbone of the ATSP foam matrix is formed while the carbonaceous nanofillers are incorporated into the polymer network via covalent conjugation with functional end-groups of the oligomers. The controlled GNP size promotes different electrical percolation thresholds and ultimate electrical conductivities. Microstructural analysis demonstrates GNP distributions in the matrix as well as morphological modifications induced by the formation of conductive percolating GNP networks. Cure characteristics reveal the thermochemical changes prompted in the polymerization processes for GNP content above the requirement for percolation formation. Chemical spectroscopy of the ATSP nanocomposite morphology exhibits the formation of a robust interfacial coupling mechanism between the GNPs and ATSP backbone. The findings here may guide the developmental efforts of nanocomposites through better identifying roles of the morphology and content of nanofillers in polymerization processes.

Physicochemical effects induced by graphene nanoplatelets on the in situ polycondensation reaction of aromatic thermosetting copolyester through the formation of conductive percolating network assembled via interfacial interactions.     

Community Factors and Hospital Readmission Rates

Objective

To examine the relationship between community factors and hospital readmission rates.

Data Sources/Study Setting

We examined all hospitals with publicly reported 30-day readmission rates for patients discharged during July 1, 2007, to June 30, 2010, with acute myocardial infarction (AMI), heart failure (HF), or pneumonia (PN). We linked these to publicly available county data from the Area Resource File, the Census, Nursing Home Compare, and the Neilsen PopFacts datasets.

Study Design

We used hierarchical linear models to assess the effect of county demographic, access to care, and nursing home quality characteristics on the pooled 30-day risk-standardized readmission rate.

Data Collection/Extraction Methods

Not applicable.

Principal Findings

The study sample included 4,073 hospitals. Fifty-eight percent of national variation in hospital readmission rates was explained by the county in which the hospital was located. In multivariable analysis, a number of county characteristics were found to be independently associated with higher readmission rates, the strongest associations being for measures of access to care. These county characteristics explained almost half of the total variation across counties.

Conclusions

Community factors, as measured by county characteristics, explain a substantial amount of variation in hospital readmission rates.     

Treatment of heterotopic caesarean scar pregnancy complicated with post termination increase in size of residual mass and morbidly adherent placenta

We report a case of a secundipara with heterotopic cesarean scar pregnancy (HCSP) treated with potassium chloride injection into the ectopic embryo followed by sac aspiration. The remaining “mass” increased in size threefold and was surrounded by a rich vascular network. An arteriovenous malformation was suspected; however, appropriate treatment was precluded because of the viability of the ectopic gestation. Sonographic examination revealed a morbidly adherent placenta, and attempt to resect the mass laparoscopically was complicated by bleeding that required hysterectomy. This case illustrates a complication of the intervention performed to preserve the intrauterine gestation in case of HCSP. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46 :227–230, 2018     

Probabilistic hazard assessment for skin sensitization potency by dose–response modeling using feature elimination instead of quantitative structure–activity relationships

Supervised learning methods promise to improve integrated testing strategies (ITS), but must be adjusted to handle high dimensionality and dose–response data. ITS approaches are currently fueled by the increasing mechanistic understanding of adverse outcome pathways (AOP) and the development of tests reflecting these mechanisms. Simple approaches to combine skin sensitization data sets, such as weight of evidence, fail due to problems in information redundancy and high dimensionality. The problem is further amplified when potency information (dose/response) of hazards would be estimated. Skin sensitization currently serves as the foster child for AOP and ITS development, as legislative pressures combined with a very good mechanistic understanding of contact dermatitis have led to test development and relatively large high‐quality data sets. We curated such a data set and combined a recursive variable selection algorithm to evaluate the information available through in silico, in chemico and in vitro assays. Chemical similarity alone could not cluster chemicals' potency, and in vitro models consistently ranked high in recursive feature elimination. This allows reducing the number of tests included in an ITS. Next, we analyzed with a hidden Markov model that takes advantage of an intrinsic inter‐relationship among the local lymph node assay classes, i.e. the monotonous connection between local lymph node assay and dose. The dose‐informed random forest/hidden Markov model was superior to the dose‐naive random forest model on all data sets. Although balanced accuracy improvement may seem small, this obscures the actual improvement in misclassifications as the dose‐informed hidden Markov model strongly reduced " false‐negatives" (i.e. extreme sensitizers as non‐sensitizer) on all data sets. Copyright © 2015 John Wiley & Sons, Ltd.