Analysis of genomic downsizing on the basis of region-of-difference polymorphism profiling of Mycobacterium tuberculosis patient isolates reveals geographic partitioning

Mycobacterium tuberculosis, the etiological agent of tuberculosis, has lost many coding and noncoding regions in its genome during the course of evolution. We performed region-of-difference (RD) analysis using PCR-based genotyping of 131 M. tuberculosis clinical isolates obtained from four different countries, namely, India, Peru, Libya, and Angola. Our studies revealed that RD patterns are often distinct for strains circulating in specific geographical regions and can be used to trace the descent and spread of an isolate from its original reservoir. We describe our findings, which show that no single isolate from the four countries (n = 131) had all the 15 RDs either deleted or retained. Tuberculosis-specific deletion 1 (TbD1) was found to be conserved in 23% of the Indian isolates, indicating their possible ancient origin. RD9 was the most conserved region, RD11 was predominantly deleted, and RD6 was the most variable among the isolates in our collection irrespective of their geographic region. In contrast to earlier reports, our results demonstrate that the deletion of RD1 does not correlate with a decrease in the virulence potential of M. tuberculosis, as Indian isolates (n = 30) examined by us were from diseased individuals and yet had lost the RD1 region. Our results further illustrated that the intactness of the RD5 region may be associated with increased virulence of the organism. This study highlights that the RDs in M. tuberculosis genomes are geographically distributed and specific and may possibly be associated with virulence spectrum.     

Depression,sleeping pattern,and suicidal ideation among medical students in Bangladesh: a cross-sectional pilot study

Journal of Public Health - Depression is a major morbidity and the most common mental disorder among the medical students in medical schools globally. Undergraduate students suffer stress more due...     

Effectiveness of Preventive Therapy for Persons Exposed at Home to Drug-Resistant Tuberculosis,Karachi, Pakistan

In Karachi, Pakistan, a South Asian megacity with a high prevalence of tuberculosis (TB) and low HIV prevalence, we assessed the effectiveness of fluoroquinolone-based preventive therapy for drug-resistant (DR) TB exposure. During February 2016–March 2017, high-risk household contacts of DR TB patients began a 6-month course of preventive therapy with a fluoroquinolone-based, 2-drug regimen. We assessed effectiveness in this cohort by comparing the rate and risk for TB disease over 2 years to the rates and risks reported in the literature. Of 172 participants, TB occurred in 2 persons over 336 person-years of observation. TB disease incidence rate observed in the cohort was 6.0/1,000 person-years. The incidence rate ratio ranged from 0.29 (95% CI 0.04–1.3) to 0.50 (95% CI 0.06–2.8), with a pooled estimate of 0.35 (95% CI 0.14–0.87). Overall, fluoroquinolone-based preventive therapy for DR TB exposure reduced risk for TB disease by 65%.     

Evidence-Based Strategies for the Treatment of Peritoneal Malignancies during Health Care Resource Restriction: The COVID-19 Pandemic

Background: The COVID-19 pandemic has put enormous pressure on hospital resources, and has affected all aspects of patient care. As operative volumes decrease, cancer surgeries must be triaged and prioritized with careful thought and attention to ensure maximal benefit for the maximum number of patients. Peritoneal malignancies present a unique challenge, as surgical management can be resource intensive, but patients have limited non-surgical treatment options. This review summarizes current data on outcomes and resource utilization to help inform decision-making and case prioritization in times of constrained health care resources. Methods: A rapid literature review was performed, examining surgical and non-surgical outcomes data for peritoneal malignancies. Narrative data synthesis was cross-referenced with relevant societal guidelines. Peritoneal malignancy surgeons and medical oncologists reviewed recommendations to establish a national perspective on case triage and mitigating treatment strategies. Results and Conclusions: Triage of peritoneal malignancies during this time of restricted health care resource is nuanced and requires multidisciplinary discussion with consideration of individual patient factors. Prioritization should be given to patients where delay may compromise resectability of disease, and where alternative treatment options are lacking. Mitigating strategies such as systemic chemotherapy and/or surgical deferral may be utilized with close surveillance for disease stability or progression, which may affect surgical urgency. Unique hospital capacity, and ability to manage the complex post-operative course for these patients must also be considered to ensure patient and system needs are aligned.     

Migration,health, and socioenvironmental safety net among children of Dhaka,Bangladesh

This study quantifies the diarrhea burden among migrant children under age 5 (who have migrated due to environmental degradation) in Dhaka. We used a multifactor socioepidemiological as well as environmental approach with pretested questionnaires and observations. It was found that 52% of the children were affected by diarrhea. Disability-adjusted life years (DALYs) lost was reduced manifold with the increase of mothers' behavioral determinants. Health losses were 1,718 fold with significant coefficient (β) in the migrant group. DALYs lost were significantly associated with socioenvironmental factors such as mother's illiteracy (β = .18; p < .001), no hand wash before eating (β = .08; p = .004), and no hand wash after defecation (β = .10; p < .001). This puts emphasis clearly on the awareness at household level, especially of mothers and children under age 5 in Dhaka, Bangladesh, in formulating migration-related policies.     

Polypyrrole/tannin biobased nanocomposite with enhanced electrochemical and physical properties

In this research, tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of a polypyrrole (PPy) composite. Brunauer–Emmett–Teller (BET) analysis presented a higher degree of surface area and porosity for the PPy/TA/CTAB nanocomposite. A highly porous and rod like structure with a lumpy surface was observed for PPy/TA prepared in the presence of CTAB by Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). Cyclic voltammograms of the modified SPE electrode using PPy/TA/CTAB displayed an enhanced current response compared to the electrode modified with only PPy or PPy/TA. Electrochemical Impedance Spectroscopy (EIS) exhibited a lower value of charge transfer resistance (R_ct) and higher electron transfer for the modified electrode, making the nanocomposite a promising candidate for biosensor application.

Tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of polypyrrole (PPy) composite.     

Evaluation of tuberculosis diagnostics in children: 1. Proposed clinical case definitions for classification of intrathoracic tuberculosis disease. Consensus from an expert panel

There is a critical need for improved diagnosis of tuberculosis in children, particularly in young children with intrathoracic disease as this represents the most common type of tuberculosis in children and the greatest diagnostic challenge. There is also a need for standardized clinical case definitions for the evaluation of diagnostics in prospective clinical research studies that include children in whom tuberculosis is suspected but not confirmed by culture of Mycobacterium tuberculosis. A panel representing a wide range of expertise and child tuberculosis research experience aimed to develop standardized clinical research case definitions for intrathoracic tuberculosis in children to enable harmonized evaluation of new tuberculosis diagnostic technologies in pediatric populations. Draft definitions and statements were proposed and circulated widely for feedback. An expert panel then considered each of the proposed definitions and statements relating to clinical definitions. Formal group consensus rules were established and consensus was reached for each statement. The definitions presented in this article are intended for use in clinical research to evaluate diagnostic assays and not for individual patient diagnosis or treatment decisions. A complementary article addresses methodological issues to consider for research of diagnostics in children with suspected tuberculosis.     

Immune Responses to the O-Specific Polysaccharide Antigen in Children Who Received a Killed Oral Cholera Vaccine Compared to Responses following Natural Cholera Infection in Bangladesh

Current oral cholera vaccines induce lower levels of protective efficacy and shorter durations of protection in young children than in adults. Immunity against cholera is serogroup specific, and immune responses to Vibrio cholerae lipopolysaccharide (LPS), the antigen that mediates serogroup-specific responses, are associated with protection against disease. Despite this, responses against V. cholerae O-specific polysaccharide (OSP), a key component of the LPS responsible for specificity, have not been characterized in children. Here, we report a comparison of polysaccharide antibody responses in children from a region in Bangladesh where cholera is endemic, including infants (6 to 23 months, n = 15), young children (24 to 59 months, n = 14), and older children (5 to 15 years, n = 23) who received two doses of a killed oral cholera vaccine 14 days apart. We found that infants and young children receiving the vaccine did not mount an IgG, IgA, or IgM antibody response to V. cholerae OSP or LPS, whereas older children showed significant responses. In comparison to the vaccinees, young children with wild-type V. cholerae O1 Ogawa infection did mount significant antibody responses against OSP and LPS. We also demonstrated that OSP responses correlated with age in vaccinees, but not in cholera patients, reflecting the ability of even young children with wild-type cholera to develop OSP responses. These differences might contribute to the lower efficacy of protection rendered by vaccination than by wild-type disease in young children and suggest that efforts to improve lipopolysaccharide-specific responses might be critical for achieving optimal cholera vaccine efficacy in this younger age group.