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* Context.--Diagnostic laboratory testing for Clostridium difficile infection has undergone considerable and rapid evolution during the last decade. The ideal detection method(s), which should exhibit high analytical and clinical sensitivity and specificity, remains undefined. Objective.--We sought to evaluate the analytical and clinical performance characteristics of three methods for the laboratory detection of C difficile. Design.--This study used 114 consecutive stool samples to compare three methods of C difficile detection: an enzyme immunoassay (EIA) for toxins A/B, a lateral flow membrane immunoassay for glutamate dehydrogenase (GDH), and a qualitative real-time polymerase chain reaction (PCR) assay. Medical records of all patients having ≥1 positive test result were reviewed to estimate the clinical likelihood of C difficile infection. Results.--Based upon laboratory result consensus values, analytical sensitivity was significantly higher for GDH (94%) and PCR (94%) assays than for toxin EIA (25%). Analytical specificity was significantly higher for PCR (100%) and EIA (100%) than for GDH assay (93%). In contrast, assay performance based upon clinical probability of C difficile infection suggested lower discriminatory power (ie, clinical specificity) of the more analytically sensitive methods. Conclusions.--Higher rates of C difficile detection will be realized upon implementation of GDH assay and/or real-time PCR-based testing algorithms than by testing with EIA alone. Further study is required to elucidate potential downstream costs for higher detection rates. (Arch Pathol Lab Med. 2012; 136:527-531; doi: 10.5858/arpa.2011-0305-OA), Laboratory testing of stool samples for toxigenic Clostridium difficile infection (CDI) has evolved considerably during the past 3 decades. Cytotoxicity to fibroblast monolayers, a key feature that helped to implicate [...]

Svensson, Annika M., Claes-Goran Ostenson, and Left Jansson. Age-induced changes in pancreatic islet blood flow: evidence for an impaired regulation in diabetic GK rats. Am J Physiol Endocrinol Metab 279: E1139-E1144. 2000.--The present study aimed to compare longitudinal variations in islet blood perfusion in rats with different degrees of impairment of glucose metabolism. For this purpose, mildly diabetic Goto-Kakizaki (GK) rats, glucose intolerant [F.sub.1] hybrids of GK and Wistar (W) rats (H), and control W rats were examined at 5 wk, 12 wk, or 1 yr of age, using the microsphere technique for blood flow measurements. W rats showed progressively increasing islet blood flow (IBF) throughout the experiment. Both GK and H rats demonstrated increasing IBF between 5 and 12 wk. However, H rats showed no further increment in IBF at 1 yr, whereas GK rats displayed a pronounced decrease in IBF between 12 wk and 1 yr of age. The augmented IBF seen in older W rats may constitute an adaptation to the increasing demand for insulin secretion in aging rats. The inability to adapt to the increased demand for insulin secretion by upregulation of islet blood flow could contribute to the progressive deterioration of glucose metabolism seen in the aging GK rat. type 2 diabetes; aging