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A total of 258 bovine-associated Staphylococcus aureus isolates from the United States, Chile, and the United Kingdom, plus the reference isolate S. aureus Newbould 305 (NCIMB 702892), were analyzed by multilocus sequence typing (MLST). A collection of previously characterized United Kingdom isolates were also included in the analysis. The results demonstrated that MLST is suitable for the differentiation of bovine S. aureus isolates from various sites (milk, teat skin, milking machine unit liners, hands, and bedding) and countries. The theory of the host specificity of S. aureus is supported by the detection of a previously undescribed clonal complex that comprised 87.4% of the isolates studied, with representatives from all geographic locations investigated. This suggests that a single clonal group has achieved a widespread distribution and is responsible for the majority of infections. Some sequence types (STs; ST25, ST115, ST124, and ST126) demonstrated site specificity, as they were significantly (P < 0.05) associated with milk or teat skin.Staphylococcus aureus is a major cause of bovine mastitis and is spread from cow to cow (skin or milk) via the milking machine (35, 57). Environmental spread may also occur, since strains of S. aureus have been isolated from the environment of dairy farms and from other species that are present on dairy farms (32,39).A number of studies have identified potential sources of the pathogen and have investigated strain-specific differences (19, 40). The major potential sources identified were milk, body sites, and, to a lesser extent, the environment (40). Studies investigating the global population structure of bovine S. aureus suggest that a relatively few specialized clones are responsible for the majority of intramammary infections (IMIs) (26, 55), although some authors did not report between-farm genetic homogeneity (25,46). Most of these studies have used techniques such as phage typing (19, 40) and pulsed-field gel electrophoresis (PFGE) (7, 25) to compare isolates. These methods lack intercenter reproducibility (55). Library typing systems such as binary typing (BT) (53) and multilocus sequence typing (MLST) (31) have been developed to overcome these problems by producing results that are repeatable between laboratories and over time.The aim of this study was to investigate the effectiveness of MLST as a method for the typing of S. aureus isolates of bovine origin from a number of distinct geographical sources. A collection of isolates previously characterized by phage typing (19) and by PFGE and binary typing (55) was used to compare these methods to MLST. The data were then used in a preliminary analysis of the evolutionary and population biology of S. aureus isolates of bovine origin.

Aims In humans, genetic variation in endocannabinergic signaling has been associated with anthropometric measures of obesity. In randomized trials, pharmacological blockade at the level of the cannabinoid receptor 1 (CNR1) receptor not only facilitates weight reduction, but also improves insulin sensitivity and clinical measures of lipid homeostasis. We therefore tested the hypothesis that genetic variation in CNR1 is associated with common obesity-related metabolic disorders. Materials & methods A total of six haplotype tagging SNPs were selected for CNR1, using data available within the Human HapMap (Centre d’Etude du Polymorphisme Humain population) these included: two promoter SNPs, three exonic SNPs, and a single SNP within the 3′-untranslated region. These tags were then genotyped in a rigorously phenotyped family-based collection of obese study subjects of Northern European origin. Results & conclusions A common CNR1 haplotype (H4; prevalence 0.132) is associated with abnormal lipid homeostasis. Additional statistical tests using single tagging SNPs revealed that these associations are partly independent of body mass index.

Postmortem specimens from a patient with rheumatoid arthritis who had received 5 g of aurothioglucose were examined histologically, and their gold content was determined by activation analysis. The highest concentration of gold was found in the lymph nodes followed by the adrenal gland, renal cortex and other organs of the reticuloendothelial system. Comparatively low concentrations were found in tissues comprising the joint structure. Organs in which the greatest quantities of gold were stored include the bone marrow, liver, skin and bone. These findings demonstrate the body's capacity to store relatively large quantities of gold without adverse reaction, support the concept of a systemic rather than local mechanism of action (at the joint level) and demonstrate in vivo gold concentrations in the range expected to produce local cellular biologic effects.The metabolic and excretory pathways of gold compounds have been of interest to investigators since their benefit in the treatment of rheumatoid arthritis was first reported more than 40 years ago (1). Abundant data are available regarding gold concentrations in blood and its components and in the urine and feces of human and experimental animal models (2-6). T' issue distribution of gold, on the other hand, has been adequately studied only in animals (7,8) Submitted for publication Apr 6, 1971; accepted June 21, 1971. tissues has never been systematically measured. There are scanty reports of gold levels in human skin, synovium, synovial fluid, etc, but methods of gold analysis were relatively insensitive and some of the patients studied had received only one injection of a radioactive gold-labeled compound rather than a course of gold therapy (2,3,9,10). No information is available regarding gold concentrations in internal organs or in the musculoskeletal system of a patient with rheumatoid arthritis on longterm chrysotherapy. The sudden death of such a patient afforded us the opportunity to analyze tissues for their gold content. CASE REPORTMV was a 68-year-old white female with classic rheumatoid arthritis, by the ARA criteria. of 16 years duration who died in November 1969, of an overdose of barbiturate. When first seen in the Arthritis Clinic at Jackson Memorial Hospital in June 1958, she related a 5-year history of progressive polyarthritis with morning stiffness. Physical examination showed active synovitis of metacarpal phalangeal and proximal interphalangeal joints, 16Arthritis and Rheumatism, Vol. 15, No. 1 (Januafy-FebrurIy 1 9 n )