Sexually transmitted infections and sexual behaviour among youth clients of hotel-based female sex workers in Dhaka, Bangladesh

A cross-sectional study was conducted among youth clients of hotel-based female sex workers (YCHBFSWs) in nine randomly selected hotels in Bangladesh to examine sexual-risk behaviour, condom use and determinants of condom use in last sex, knowledge of HIV, sexually transmitted infection (STI) prevalence and STI care-seeking behaviour. A prestructured questionnaire was used to collect sociodemographic, behavioural, clinical information; urine specimens (before sex) and blood were collected for diagnosis of Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis, syphilis and herpes simplex virus 2 (HSV2) infection. One thousand and thirteen participants were enroled in the study. Approximately half of them reported visiting female sex workers (FSWs) at least once a month and 25% visited FSWs at least once a week. Only 12% of participants reported regular condom use. The prevalence of N. gonorrhoeae, C. trachomatis, T. vaginalis, syphilis and HSV2 was 2.2%, 3.9%, 7.2%, 2.6% and 12.9%, respectively. Only 15.3% of the YCHBFSW sought STI care in the past year. Negotiation of condom use with FSWs was the main determinant (odds ratio = 17.95) for condom use at last sex. Male clients of FSWs, including YCHBFSW, are an important bridge population for HIV transmission in Bangladesh and HIV interventions should be designed and implemented for them.

Occurrence and characterization of multidrug-resistant New Delhi metallo-β-lactamase-1-producing bacteria isolated between 2003 and 2010 in Bangladesh

The purpose of this study was to screen for reduced susceptibility against imipenem and the presence of the New Delhi metallo-β-lactamase-1 (NDM-1) gene in a collection of Enterobacteriaceae (Escherichia coli, Shigella spp. and Klebsiella pneumoniae) from different surveillance studies between 2003 and 2010 at the International Centre for Diarrhoeal Disease Research, Bangladesh. None of the E. coli (n = 1789) and Shigella spp. (n = 90) isolated between 2009 and 2010 from stool samples was resistant or had intermediate susceptibility to imipenem. Among 127 extended-spectrum β-lactamase-producing strains isolated during 2003-2009, three Klebsiella pneumoniae isolates (2.4 %) were resistant to imipenem and were positive for bla(NDM-1). All these NDM-1-producing strains were isolated in 2008 and were resistant to all antibiotics tested except for tigecycline and colistin. All three isolates were positive for bla(OXA-1) group, bla(CTX-M-1) group (bla(CTX-M-15)) and bla(SHV) genes, whilst two isolates were positive for 16S rRNA methylase (armA) and qnr (qnrB) genes. One isolate was positive for the bla(CMY) gene and one for the rmtB gene. The bla(NDM-1) gene was located on a conjugative plasmid of ~23-24 MDa. The PFGE patterns of the isolates were different from each other. This study highlights the occurrence of NDM-1-producing organisms in Bangladesh in 2008. The clonal diversity of the isolates and the transferability of bla(NDM-1) plasmids suggest a wider distribution of NDM-1-producing bacteria in Bangladesh.

Histopathological study comparing upstream binding factor expression and AgNOR staining

AgNOR staining has been in past years, the subject of numerous publications, which have failed to reach agreement regarding its usefulness as a proliferation marker. This silver staining method does not react with NORs (actual chromosome regions containing rRNA (ribosomal RNA) genes), but with proteins associated with them, whose quantity increases in parallel with ribosome biogenesis. The transcription factor UBF (upstream binding factor) is associated with NORs and has an important regulatory role in rRNA synthesis as cofactor of RNA polymerase I. Recent research has revealed an additional cytoarchitectural function of UBF in decondensing r-chromatin (ribosomal-chromatin). Immune detection of UBF expression and AgNOR counts are closely correlated as both techniques identify substrates in or closely adjacent to NORs. However, contrary to AgNOR dots, the UBF signal disappears in cells which undergo apoptosis or terminal differentiation. These features imply that UBF evaluation would reflect tumour cell proliferation (growth fraction) more accurately than AgNOR counts. Here we also show that immunohistochemical staining of UBF may reveal distinct active NORs with open, decondensed chromatin and we hypothesize that the large stretches of decondensed r-chromatin revealed by UBF staining may correspond to clusters seen after silver staining and, conversely, shorter areas of decondensed r-chromatin should match the small AgNOR grains typically found in some tumour types. The length of decondensed r-chromatin may be a reflection of the ratio of active to silent r-RNA genes.