Molecular diversity of Staphylococcus aureus and the role of milking equipment adherences or biofilm as a source for bulk tank milk contamination.

Staphylococcus aureus is one of the most frequent pathogens causing intramammary infections in dairy herds. Consequently, virulence factors, pathobiology, and epidemiology of Staphylococcus aureus strains have been widely assessed through the years. Nevertheless, not much has been described about the epidemiology of Staph. aureus strains from bulk tank milk (BTM) and adherences on milking equipment (AMES), even when these strains may play a role in the quality of milk that is intended for human consumption. The objective of this study was to assess the strain diversity of 166 Staph. aureus isolates collected from 3 consecutive BTM samples, and from AMES in contact with milk from 23 Chilean dairy farms. Isolates were analyzed and typed using pulsed-field gel electrophoresis. Diversity of strains, both within and among farms, was assessed using Simpson's index of diversity (SID). On farms where Staph. aureus was isolated from both AMES and BTM (n = 8), pulsotypes were further analyzed to evaluate the role of AMES as a potential source of Staph. aureus strains in BTM. Among all Staph. aureus analyzed by pulsed-field gel electrophoresis, a total of 42 pulsotypes (19 main pulsotypes and 23 subtypes) were identified. Among dairy farms, strain diversity was highly heterogeneous (SID = 0.99). Within dairy farms, Staph. aureus strain diversity was variable (SID = 0 to 1), and 18 dairy operations (81.8%) had one pulsotype that was shared between at least 2 successive BTM samples. In those farms where Staph. aureus was isolated in both AMES and BTM (n = 8), 7 (87.5%) showed a clonal distribution of Staph. aureus strains between these 2 types of samples. The overlapping of certain Staph. aureus strains among dairy farms may point out common sources of Staph. aureus among otherwise epidemiologically unrelated farms. Indistinguishable Staph. aureus strains between AMES and BTM across dairy farms suggest that Staph. aureus-containing AMES may represent a source for BTM contamination, thus affecting milk quality. Our study highlights the role of viable Staph. aureus in AMES as a source for BTM contamination on dairy farms, and also describes the overlapping and presence of specific BTM and AMES pulsotypes among farms.

Concurrent cisplatin/gemcitabine chemotherapy along with radiotherapy in locally advanced cervical carcinoma: a phase II trial.

OBJECTIVE: To evaluate the efficacy and safety of a concurrent regimen of gemcitabine/cisplatin and radiotherapy in women with locally advanced cervical carcinoma (LACC). METHODS: From April 2001 to June 2002, we enrolled women diagnosed with histologically proven LACC (FIGO stages IIA through IIIB), for treatment with concurrent regimen of chemo-radiotherapy. The treatment consisted of: cisplatin 40 mg/m(2), followed by gemcitabine 125 mg/m(2), once weekly, given about 1 to 2 h before radiotherapy. External beam radiation was delivered 5 days/week to entire pelvic radiation field for a total of 50 Gy in 25 fractions over 5 weeks. After completion of external radiation, patients received brachytherapy with cesium-137 via standard Fletcher-suit applicators delivering 30 Gy to point A. RESULTS: Of the 23 enrolled patients (mean age 47 years), 20 completed the treatment and were evaluable for response and safety. The complete response rate was 90% (18/20), and partial response rate was 10% (2 patients with persistent disease after therapy). Toxicity was moderate: 2 patients required blood transfusions; 5% patients had grade 2 leukopenia or thrombocytopenia; 40% had grade 1-2 nausea-vomiting, and 50% had grade 1 diarrhea. At a median follow-up of 12 months, all patients are alive, and 16/20 (80%) are disease-free. CONCLUSIONS: The gemcitabine/cisplatin combination administered concurrently with radiotherapy is highly active in locally advanced cervical carcinoma. The tolerable toxicity and synergistic activity of this concurrent chemoradiation regimen are consistent with prior reports. Definitive results are awaited from an on-going large, randomized trial comparing this regimen with standard treatment.