Mycolactone Gene Expression Is Controlled by Strong SigA-Like Promoters with Utility in Studies of Mycobacterium ulcerans and Buruli Ulcer

Mycolactone A/B is a lipophilic macrocyclic polyketide that is the primary virulence factor produced by Mycobacterium ulcerans, a human pathogen and the causative agent of Buruli ulcer. In M. ulcerans strain Agy99 the mycolactone polyketide synthase (PKS) locus spans a 120 kb region of a 174 kb megaplasmid. Here we have identified promoter regions of this PKS locus using GFP reporter assays, in silico analysis, primer extension, and site-directed mutagenesis. Transcription of the large PKS genes mlsA1 (51 kb), mlsA2 (7 kb) and mlsB (42 kb) is driven by a novel and powerful SigA-like promoter sequence situated 533 bp upstream of both the mlsA1 and mlsB initiation codons, which is also functional in Escherichia coli, Mycobacterium smegmatis and Mycobacterium marinum. Promoter regions were also identified upstream of the putative mycolactone accessory genes mup045 and mup053. We transformed M. ulcerans with a GFP-reporter plasmid under the control of the mls promoter to produce a highly green-fluorescent bacterium. The strain remained virulent, producing both GFP and mycolactone and causing ulcerative disease in mice. Mosquitoes have been proposed as a potential vector of M. ulcerans so we utilized M. ulcerans-GFP in microcosm feeding experiments with captured mosquito larvae. M. ulcerans-GFP accumulated within the mouth and midgut of the insect over four instars, whereas the closely related, non-mycolactone-producing species M. marinum harbouring the same GFP reporter system did not. This is the first report to identify M. ulcerans toxin gene promoters, and we have used our findings to develop M. ulcerans-GFP, a strain in which fluorescence and toxin gene expression are linked, thus providing a tool for studying Buruli ulcer pathogenesis and potential transmission to humans

Effective antimicrobial therapies of urinary tract infections among children in low‐ and middle‐income countries: A systematic review

ABSTRACT Importance Urinary tract infection (UTI) is one of the most common infections encountered in infancy and childhood. Despite the emerging problem of antibiotic resistance in recent years, the use of antibiotics for better management of UTIs is inevitable. Objective This study aims to explore the efficacy and adverse effects of the available antimicrobial agents that are used in pediatric UTIs in low‐ and middle‐income countries (LMICs). Methods Five electronic databases were searched to identify relevant articles. Two reviewers independently performed screening, data extraction, and quality assessment of the available literature. Randomized controlled trials providing antimicrobial interventions in both male and female participants within the age range of 3 months to 17 years in LMICs were included. Results Six randomized controlled trials from 13 LMICs were included in this review (four trials explored the efficacy). Due to high heterogeneity across the studies, a meta‐analysis was not performed. Other than attrition and reporting bias, the risk of bias was moderate to high due to poor study designs. The differences in the efficacy and adverse events of different antimicrobials were not found to be statistically significant. Interpretation This review indicates the necessity for additional clinical trials on children from LMICs with more significant sample numbers, adequate intervention periods, and study design

The current state of mental healthcare in Bangladesh: part 2 - setting priorities.

This is the second of a two-part profile on mental healthcare in Bangladesh. It describes the state of mental health research in the country and presents a set of priorities for addressing improvements to the fundamental gaps in mental healthcare highlighted in part 1. Focus on building infrastructure for public mental health facilities, training skilled mental health professionals, adequate distribution of financial resources and addressing stigma are all priorities that will contribute to significantly improving mental healthcare in Bangladesh

The current state of mental healthcare in Bangladesh: part 1 - an updated country profile.

Mental health is a significant factor for a sound and productive life; nevertheless, mental disorders do not often receive adequate research attention and are not addressed as a serious public health issue in countries such as Bangladesh. Part 1 of this two-part profile describes the current situation of mental health in Bangladesh in its wider sociocultural context, outlining existing policies and highlighting mental illness as a neglected healthcare problem in the country using a narrative synthesis method. The prevalence of mental disorders is very high and augmented in nature among different population groups in Bangladesh. A lack of public mental health facilities, scarcity of skilled mental health professionals, insufficient financial resource distribution, inadequately stewarded mental health policies and stigma contribute to making current mental healthcare significantly inadequate in Bangladesh. The country has few community care facilities for psychiatric patients. Furthermore, the current mental health expenditure by the Bangladeshi government is only 0.44% of the total health budget. Less than 0.11% of the population has access to free essential psychotropic medications