Comparison of urine and self-collected vaginal samples for detecting human papillomavirus DNA in pregnant women.

OBJECTIVE: To investigate the utility of urine sampling for detecting human papillomavirus (HPV) DNA among pregnant women and to compare HPV DNA detection in urine with detection in vaginal samples. METHODS: In a cross-sectional study, urine and vaginal samples were self-collected from pregnant women attending prenatal care at Hospital Divina Providencia, Frederico Westphalen, Brazil, between October 2006 and August 2007. Part of the L1 region of the HPV genome was amplified via GP5(+)/bioGP6(+) primers. Positive urine was genotyped for high-risk HPV genotypes (HPV16, HPV18, HPV31, HPV33, HPV39, HPV45, and HPV59). RESULTS: During the study period, urine samples were obtained from 133 pregnant women, 63 of whom also self-collected vaginal samples. HPV DNA was detected in 54.0% (34/63) and 61.9% (39/63) of urine and vaginal samples, respectively. HPV infection was significantly associated with first intercourse at younger than 20 years of age (P=0.008). There was substantial agreement in HPV DNA test results between the urine and vaginal samples (κ value, 77.3%; P<0.0001). HPV31 and HPV16 accounted for 80.7% of the oncogenic types identified. CONCLUSION: Detection of HPV DNA in urine showed good agreement with detection in self-collected vaginal samples, indicating that urine might be a reliable sample for HPV testing among pregnant women.

Correlations of mutations in katG, oxyR-ahpC and inhA genes and in vitro susceptibility in Mycobacterium tuberculosis clinical strains segregated by spoligotype families from tuberculosis prevalent countries in South America.

BACKGROUND: Mutations associated with resistance to rifampin or streptomycin have been reported for W/Beijing and Latin American Mediterranean (LAM) strain families of Mycobacterium tuberculosis. A few studies with limited sample sizes have separately evaluated mutations in katG, ahpC and inhA genes that are associated with isoniazid (INH) resistance. Increasing prevalence of INH resistance, especially in high tuberculosis (TB) prevalent countries is worsening the burden of TB control programs, since similar transmission rates are noted for INH susceptible and resistant M. tuberculosis strains. RESULTS: We, therefore, conducted a comprehensive evaluation of INH resistant M. tuberculosis strains (n = 224) from three South American countries with high burden of drug resistant TB to characterize mutations in katG, ahpC and inhA gene loci and correlate with minimal inhibitory concentrations (MIC) levels and spoligotype strain family. Mutations in katG were observed in 181 (80.8%) of the isolates of which 178 (98.3%) was contributed by the katG S315T mutation. Additional mutations seen included oxyR-ahpC; inhA regulatory region and inhA structural gene. The S315T katG mutation was significantly more likely to be associated with MIC for INH >or=2 microg/mL. The S315T katG mutation was also more frequent in Haarlem family strains than LAM (n = 81) and T strain families. CONCLUSION: Our data suggests that genetic screening for the S315T katG mutation may provide rapid information for anti-TB regimen selection, epidemiological monitoring of INH resistance and, possibly, to track transmission of INH resistant strains.

Phenotypic and genotypic characterization of drug-resistant Mycobacterium tuberculosis strains.

Of 142 pulmonary tuberculosis patients, 76 were considered high risk for the development of resistance, and 24 were confirmed as resistant strain carriers. Resistant isoniazid strains presented a high frequency of katG and ahpC mutations (90%) correlated with an MIC >4 microg/mL (94%). inhA mutations were not seen. rpoB mutations were identified in 78.6% of rifampicin-resistant strains, usually in codon 531 (72.7%), and 75% had an MIC >16 microg/mL. katG and rpoB mutations recognized 88.2% of multidrug-resistant strains and proved more efficient than the katG and rpoB mutations alone. Seventy percent of resistant pyrazinamide strains had pncA mutations between genes 136 and 188, 62.5% of them with an MIC >900 microg/mL. Pyrazinamidase inactivity was not an efficient resistance marker because 60% of pncA-mutated strains maintained enzymatic activity despite displaying good correlation with high resistance levels. Resistant ethambutol strains had embB mutations in codon 306, with MIC >16 microg/mL.

Superoxide dismutases in the entomopathogenic fungus Metarhizium anisopliae

Control of gene expression is a key subject in Molecular Biology. Superoxide dismutases are essential enzymes to protect living organisms against toxicity of radicals generated by the metabolism and represent an ideal system to study gene regulation. Filamentous fungi are extensively used as model eukaryotic systems and some representatives are important microorganisms in the biological control of insects in agriculture. Metarhizium anisopliae is employed at a commercial scale to control insects in sugar-cane plantations and pastures in Brazil and is currently the best studied entomopathogenic fungus. It possesses three SOD activities, CuZnSOD, MnSOD and Fe SOD. The iron enzyme is found in fungi for the first time. A gene coding for SOD was cloned by PCR amplification, partially sequenced and is under characterization. Transformation systems are developed but rendering poor efficiencies. Homologous genes have been isolated and should increase transformation yields.