Significant increase in the prevalence of Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus, particularly the USA300 variant ΨUSA300, in the Japanese community.

IMPORTANCE: USA300 is an MRSA clone producing PVL, a toxin associated with SSTIs. ΨUSA300 is a USA300 variant recently identified in Japan by Takadama et al. (15). Here, we found that the prevalence rate of PVL-positive MRSA in S. aureus was elevated in the Japanese community, and ΨUSA300 accounted for most of them. ΨUSA300 strains have been isolated from several areas in Japan and were associated with deep-seated SSTIs. This study highlighted the emerging threat posed by ΨUSA300 in Japan.

Distribution of polycyclic aromatic hydrocarbons (PAHS) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels.

A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals (EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines during 1994-1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent of industrialization in these regions. No consistent relationship between concentrations of phenolic EDCs and LABs were found, suggesting that sewage is not a major source of EDCs. Concentrations of PAHs ranged from 11 to 1,133 ng/g-dry, which were categorized as "low to moderate" levels of pollution. The ratio of methylphenanthrenes to phenanthrene (MP/P ratio) was >1.0 in 20 out of 25 locations, indicating extensive input of petrogenic PAHs. This study provides a bench-mark for data on the distribution of anthropogenic contaminants in this region, which is essential in evaluating temporal and spatial variation and effect of future regulatory measures.

Investigation of the clinical effect of large volume leukocytapheresis on methotrexate-resistant rheumatoid arthritis.

Leukocytapheresis (LCAP) is already being used in a clinical setting for the treatment of autoimmune diseases such as inflammatory bowel disease and rheumatoid arthritis, and it has been reported to be effective. However, it is totally or partially ineffective in some patients, which has forced clinicians to rethink therapeutic strategies and concurrent treatment. With the aim of enhancing the therapeutic effect, we carried out large volume leukocytapheresis, with a throughput of 5000 mL instead of the 3000-mL throughput of conventional leukocytapheresis in nine patients with rheumatoid arthritis resistant to methotrexate treatment. Using Cellsorba, the column filled with the unwoven fabric made of the polyethylene phthalate, a leukocyte removal filter, large volume leukocytapheresis was carried out once a week for a total of five sessions. The observation period was the 12-week period following completion of treatment. The American College of Rheumatology (ACR) core set was used for assessment of efficacy. Eight weeks after completion of treatment, a 20% improvement in ACR was observed in 77.8% (7/9) of subjects, a 50% improvement in ACR was seen in 55.6% (5/9) of subjects, and a 70% improvement in ACR was observed in 22.2% (2/9) of subjects. C-reactive protein decreased gradually as treatment progressed, and a significant decrease was observed 4 weeks after completion of treatment. The fact that some subjects had an ACR70 response, few reports of which are observed in the case of conventional leukocytapheresis, and the fact that the effect continued up to 12 weeks after completion of treatment suggests that the degree and duration of the effect of large volume leukocytapheresis might be longer than those of conventional leukocytapheresis.