Cystic fibrosis (CF) is a recessive disease that affects multiple organs. It is caused by mutations in CFTR. Animal modeling of this disease has been challenging, with species-and strain-specific differences in organ biology and CFTR function influencing the emergence of disease pathology. Here, we report the phenotype of a CFTR-knockout ferret model of CF. Neonatal CFTR-knockout ferrets demonstrated many of the characteristics of human CF disease, including defective airway chloride transport and submucosal gland fluid secretion; variably penetrant meconium ileus (MI); pancreatic, liver, and vas deferens disease; and a predisposition to lung infection in the early postnatal period. Severe malabsorption by the gastrointestinal (GI) tract was the primary cause of death in CFTR-knockout kits that escaped MI. Elevated liver function tests in CFTR-knockout kits were corrected by oral administration of ursodeoxycholic acid, and the addition of an oral proton-pump inhibitor improved weight gain and survival. To overcome the limitations imposed by the severe intestinal phenotype, we cloned 4 gut-corrected transgenic CFTR-knockout kits that expressed ferret CFTR specifically in the intestine. One clone passed feces normally and demonstrated no detectable ferret CFTR expression in the lung or liver. The animals described in this study are likely to be useful tools for dissecting CF disease pathogenesis and developing treatments.

Evidence of a mortality benefit continues to elude ovarian cancer (OC) screening. Data from the US Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial which used a screening strategy incorporating CA125 cut-off and transvaginal ultrasound has not shown mortality benefit. The United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) is using the Risk of Ovarian Cancer (ROC) time series algorithm to interpret CA125, which has shown an encouraging sensitivity and specificity however the mortality data will only be available in 2015. The article explores the impact of growing insights into disease aetiology and evolution and biomarker discovery on future screening strategies. A better understanding of the target lesion, improved design of biomarker discovery studies, a focus on detecting low volume disease using cancer specific markers, novel biospecimens such as cervical cytology and targeted imaging and use of time series algorithms for interpreting markers profile suggests that a new era in screening is underway.

A comparative study of histochemical detection of eosinophils in fixed murine tissue is lacking. Five histochemical methods previously reported for eosinophil detection were quantitatively and qualitatively compared in an established murine RSV vaccine-enhanced inflammation model. Nonspecific neutrophil staining was evaluated in tissue sections of neutrophilic soft tissue lesions and bone marrow from respective animals. Eosinophils had granular red to orange-red cytoplasmic staining, depending on the method, whereas neutrophils had, when stained, a more homogenous cytoplasmic pattern. Nonspecific background staining of similar coloration was variably seen in vascular walls and erythrocytes. Astra Blue/Vital New Red, Congo Red, Luna, Modified Hematoxylin and Eosin, and Sirius Red techniques were all effective in detecting increased eosinophil recruitment compared to controls; however, differences in eosinophil quantification varied significantly between techniques. Astra Blue/Vital New Red had the best specificity for differentiating eosinophils and neutrophils but had a reduced ability to enumerate eosinophils and was the most time intensive. The Luna stain had excessive nonspecific staining of tissues and a reduced enumeration of infiltrating eosinophils, which made it suboptimal. For multiple parameters such as eosinophil detection, specificity, and contrast with background tissues, the Sirius Red followed by Congo Red and Modified Hematoxylin and Eosin methods were useful, each with their own staining qualities.

T he initial report of the plasmid-mediated colistin resistance gene mcr-1 detected in Escherichia coli isolates from China (1) and the numerous follow up publications reporting livestock and clinical isolates carrying this gene raise serious concerns about the potential for the dissemination of a mobile gene encoding resistance to one of the few treatment options that have been used for infections caused by multidrug-resistant (MDR) and carbapenem-resistant Enterobacteriaceae (CRE) isolates displaying elevated MICs for more widely used and less toxic antimicrobial agents.In this report, 390 E. coli and Klebsiella pneumoniae clinical isolates displaying elevated colistin MIC results (Ն4 g/ml) collected during a 2-year period as part of a large global surveillance program were screened for the presence of mcr-1. In addition, 314 CRE isolates collected as part of the SENTRY Antimicrobial Surveillance Program during 2015 were screened for mcr-1. This report includes an mcr-1-harboring E. coli isolate from the United States collected in May 2015.During 2014 and 2015, 21,006 E. coli (n ϭ 13,526) and K. pneumoniae (n ϭ 7,480) isolates were collected in 183 hospitals located in the Asia-Pacific region (n ϭ 15), Europe (n ϭ 46), Latin America (n ϭ 9), and North America (n ϭ 113) as part of the SENTRY Program. Isolates were tested for susceptibility against colistin and other antimicrobial agents by the reference broth microdilution method as described by the Clinical and Laboratory Standards Institute (2). Categorical interpretations from CLSI document M100-S26 (3), the EUCAST website for colistin (http://www.eucast.org/clinical_breakpoints/), or the U.S. Food and Drug Administration (FDA) package inserts for tigecycline and ceftazidime-avibactam were applied. Quality control was performed using E. coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853, and the results were within specified ranges as published by the CLSI (3).A total of 390 (1.9% of overall isolates) E. coli (n ϭ 59; 0.4% for this species) and K. pneumoniae (n ϭ 331; 4.4% for this species) isolates displayed colistin MICs of Ն4 g/ml (the EUCAST resistance breakpoint for Enterobacteriaceae) and were submitted for a PCR assay targeting mcr-1. Amplicons generated were sequenced on both strands; nucleotide and deduced amino acid sequences were analyzed and compared with those available via Internet sources. Among colistin-resistant isolates, 19 (4.9% of colistinresistant [by EUCAST criteria] isolates and Ͻ0.1% overall) were positive for mcr-1, including 8 isolates from 2014 and 11 isolates from 2015. These 19 isolates were all E. coli (32.2% of colistinresistant E. coli isolates; 0.1% overall for this species) distributed in 10 countries (Table 1): Belgium (1 isolate), Brazil (1 isolate), Germany (5 isolates), Hong Kong (1 isolate), Italy (4 isolates), Malaysia (1 isolate), Poland (1 isolate), Russia (1 isolate), Spain (3 isolates), and the United States (1 isolate). Isolates positive for mcr-1 were associated with bloodstream infections (8 isolates), skin a...

Diabetes is a common and significant comorbidity in cystic fibrosis (CF). The pathogenesis of CF-related diabetes (CFRD) is incompletely understood. Because exocrine pancreatic disease is similar between humans and pigs with CF, the CF pig model has the potential to contribute significantly to the understanding of CFRD pathogenesis. We determined the structure of the endocrine pancreas in fetal, newborn and older CF and non-CF pigs and assessed endocrine pancreas function by intravenous glucose tolerance test (IV-GTT). In fetal pigs, pancreatic insulin and glucagon density was similar between CF and non-CF. In newborn and older pigs, the insulin and glucagon density was unchanged between CF and non-CF per total pancreatic area, but increased per remnant lobular tissue in CF reflecting exocrine pancreatic loss. Although fasting glucose levels were not different between CF and non-CF newborns, CF newborns demonstrated impaired glucose tolerance and increased glucose area under the curve during IV-GTT. Second phase insulin secretion responsiveness was impaired in CF newborn pigs and significantly lower than that observed in non-CF newborns. Older CF pigs had elevated random blood glucose levels compared to non-CF. In summary, glycemic abnormalities and insulin secretion defects were present in newborn CF pigs and spontaneous hyperglycemia developed over time. Functional changes in CF pig pancreas were not associated with a decline in islet cell mass. Our results suggest that functional islet abnormalities, independent of structural islet loss, contribute to the early pathogenesis of CFRD.