Search

Many intrinsic and extrinsic factors can affect an individual patient's drug exposure and response.1 The US Food and Drug Administration (FDA) has published a number of guidances that recommend how and when to evaluate these factors during drug development.2 The most recent FDA draft guidance on drug interactions3 provides advice for in vitro and in vivo drug interaction studies, including suggestions for study design, dosing strategies and analysis, and interpretation of data for medical product labels. The draft guidance3 updated the FDA's recommendations on the evaluation of important cytochrome P450 (CYP) enzyme- and transporter-based drug interactions during drug development. [ABSTRACT FROM AUTHOR]

The spirochetes inhabiting the large intestines of humans and animals consist of a diverse group of related organisms. Intestinal spirochetosis caused by Serpulina pilosicoli is a newly recognized enteric disease of human beings and animals with potential public health significance. The purpose of this study was to determine the species identity of canine intestinal spirochetes by comparing 30 isolates obtained from dogs in Australia (n = 25) and the United States (n = 5) with reference strains representing Serpulina species and Brachyspira aalborgi, by phenotypic and genetically based typing methods. All of the canine isolates were indole negative and produced a weak beta-hemolysis when cultured anaerobically on agar medium containing blood. Four isolates were identified as S. pilosicoli by 16S rRNA-specific PCR assays, rRNA gene restriction fragment length polymorphism or ribotyping, and multilocus enzyme electrophoresis. The remaining 26 isolates formed a cluster related to porcine Serpulina innocens as determined by multilocus enzyme electrophoresis but had a unique ribotype pattern. The data suggested the existence of a novel Serpulina species, provisionally designated "Serpulina canis," colonizing the intestines of dogs.