Isolation of Salmonella spp. from lettuce and evaluation of its susceptibility to novel bacteriocins of Bacillus thuringiensis and antibiotics.

In this study, 13% of fresh lettuce (Lactuca sativa) samples collected from markets and supermarkets in two cities of Mexico were contaminated with Salmonella spp. From those samples, amplicons of ∼300 base pairs (bp) were amplified, corresponding to the expected size of the invasion (invA) and internal transcribed spacer regions of the 16S and 23S rRNA genes of Salmonella spp. Additionally, Salmonella strains were isolated and harbored plasmids ranging from ∼9 to 16 kbp. From these strains, 91% were resistant to ampicillin and nitrofurantoin, whereas 55% were resistant to cephalothin and chloramphenicol. No resistance was detected to amikacin, carbenicillin, cefotaxime, gentamicin, netilmicin, norfloxacin, and sulfamethoxazole-trimethoprim. When Salmonella isolates were tested against novel bacteriocins (morricin 269, kurstacin 287, kenyacin 404, entomocin 420, and tolworthcin 524) produced by five Mexican strains of Bacillus thuringiensis, 50% were susceptible to these antimicrobial peptides. This is the first report showing that Salmonella strains isolated from lettuce are susceptible to bacteriocins produced by the most important bioinsecticide worldwide, suggesting the potential use of these antibacterial peptides as therapeutic agents or food preservatives to reduce or destroy populations of Salmonella spp.

Evaluation of the serum testosterone to prostate-specific antigen ratio as a predictor of prostate cancer risk.

OBJECTIVE: To analyse the ratio of serum testosterone (sT) to prostate-specific antigen (PSA) as a predictor of prostate cancer risk, as low levels of sT have been related to a greater risk of prostate cancer, and its ratio with serum PSA level was recently proposed as a new tool to increase the specificity of PSA. PATIENTS AND METHODS: In all, 439 consecutive men with a normal digital rectal examination and a serum PSA level of 4.1-20 ng/mL had a transrectal ultrasonography-guided biopsy using a 10-core scheme, with an additional 1-8 cores according to prostate volume and patient age. The sT level was determined before the procedure using a chemiluminescent assay, and the ratio of sT to PSA (sT/PSA) was calculated after transforming sT measurements from ng/dL to ng/mL. The percentage free PSA (%fPSA) and PSA density were also included in this analysis. RESULTS: The overall cancer detection rate was 42.1%. The median sT level was 469 ng/dL in men with cancer and 499 ng/dL in those without (P = 0.521). The median sT/PSA was 0.68 and 0.74, respectively (P = 0.215). However, the median %fPSA was 14 in men with cancer and 17 in men without (P < 0.001) and the median PSA density was 0.22 and 0.16, respectively (P < 0.001). The multivariate analysis confirmed the independent predictive value only for %fPSA (odds ratio 0.94, 95% confidence interval 0.91-0.98) and PSA density (5.8, 3.42-19.8). CONCLUSION: These results do not support the use of sT/PSA for predicting the risk of prostate cancer and to increase the specificity of PSA.

The relationship between total and free serum testosterone and the risk of prostate cancer and tumour aggressiveness.

OBJECTIVE: To analyse the relationship between the levels of total and free serum testosterone and the risk of prostate cancer and tumour aggressiveness. PATIENTS AND METHODS: Total and free serum testosterone were determined in 478 patients consecutively assessed by transrectal ultrasonography-guided prostate biopsy because of an abnormal digital rectal examination and/or serum prostate-specific antigen (PSA) level of >4.0 ng/mL. Tumour aggressiveness was assessed according to serum PSA level, biopsy Gleason score and clinical stage in the subset of 216 patients with cancer (45.2%). We also compared prostate cancer risk and tumour aggressiveness in 80 hypogonadal patients (16.7%) and 398 eugonadal patients (83.3%). RESULTS: The median total serum testosterone level in patients without and with prostate cancer was 466.0 and 466.5 ng/dL, respectively (P > 0.05); the median levels of free serum testosterone were 9.9 and 10.0 pg/mL, respectively (P > 0.05). The cancer detection rate in hypogonadal patients was 41.3% (33/80) and 46.0% in eugonadal patients (183/398) (P > 0.05). The median level of total testosterone was 433 ng/dL in patients with low-risk prostate cancer, 467 ng/dL in those with intermediate-risk tumours and 468 ng/dL in those with high-risk tumours (P > 0.05); the median levels of free testosterone were 9.4, 9.8 and 10.3 pg/mL, respectively (P > 0.05). CONCLUSIONS: Prostate cancer risk and tumour aggressiveness are not related to serum levels of total and free testosterone, but hypogonadal patients do not have a greater risk of prostate cancer and tumour aggressiveness.

Comparison of diagnostic sensitivities of three assays (Bartels enzyme immunoassay [EIA], Biotest EIA, and Binax NOW immunochromatographic test) for detection of Legionella pneumophila serogroup 1 antigen in urine.

The Bartels enzyme immunoassay (EIA), Biotest EIA, and Binax NOW immunochromatographic test (ICT) urinary antigen kits for the detection of Legionella pneumophila serogroup 1 were compared using 178 frozen urine samples. When nonconcentrated urine samples were used, the sensitivity levels of both enzyme EIAs were significantly higher than the sensitivity level of the ICT (Bartels EIA, 71.3%; Biotest EIA, 65.1%; Binax NOW ICT, 37% [P < 0.001]). After concentration of the urine samples, no significant differences in sensitivity were found among the three tests.

Varón con fiebre, dolor y limitación funcional del hombro derecho / Man with fever, pain and funtional limitation of the right shoulder

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Epulis fisurado

Se realiza un breve recuento de los aspectos clínicos, etiológicos histopatológicos y terapéuticos del épulis fisurado, proponiéndose una técnica quirúrgica moderna y ventajosa para la exéresis de estas lesiones(AU)