Conductive textiles for signal sensing and technical applications

Conductive textiles have found notable applications as electrodes and sensors capable of detecting biosignals like the electrocardiogram (ECG), electrogastrogram (EGG), electroencephalogram (EEG), and electromyogram (EMG), etc; other applications include electromagnetic shielding, supercapacitors, and soft robotics. There are several classes of materials that impart conductivity, including polymers, metals, and non-metals. The most significant materials are Polypyrrole (PPy), Polyaniline (PANI), Poly(3,4-ethylenedioxythiophene) (PEDOT), carbon, and metallic nanoparticles. The processes of making conductive textiles include various deposition methods, polymerization, coating, and printing. The parameters, such as conductivity and electromagnetic shielding, are prerequisites that set the benchmark for the performance of conductive textile materials. This review paper focuses on the raw materials that are used for conductive textiles, various approaches that impart conductivity, the fabrication of conductive materials, testing methods of electrical parameters, and key technical applications, challenges, and future potential

Multidrug resistant tuberculosis (MDR-TB) in community setting of Bangladesh

Research Doctorate - Doctor of Philosophy (PhD)Background: Bangladesh is one of the high burden countries for tuberculosis (TB) as well as for multi-drug resistant tuberculosis (MDR-TB). Research projects presented in this thesis addressed the following areas: risk factors for development of MDR-TB; factors related to previous tuberculosis treatment of MDR-TB patients; delays in treatment of drug sensitive tuberculosis patients; and the health system delay in the treatment of MDR-TB patients, in Bangladesh. Method: This thesis by publication consists of four papers. A case control study of 250 MDR-TB patients as cases and 750 drug sensitive TB patients as controls was conducted to determine the risk factors of MDR-TB in Bangladesh. A total 293 patients of the same dataset, who had history of previous tuberculosis treatment, were included in the second study to identify the factors related to previous tuberculosis treatment. MDR-TB patients who were diagnosed using the rapid diagnostic tests (n=207), were included in our fourth study, to determine the health system delay in MDR-TB treatment. We had conducted another cross sectional study (n=7280) to determine the delay in drug sensitive TB patient which has also been included in this thesis. Key findings: Our first study suggests that previous tuberculosis treatment is the major contributing factor to MDR-TB (OR 716.6, 95% CI 282.1-1820.8). Other factors found to be associated with MDR-TB are age group “18-25” (OR 1.8, CI 1.1-2.9) and “26-45” (OR 1.7, CI 1.1-2.7), compared to the age-group “ >45 years”; patient’s education up to secondary level (OR 1.9, CI 1.32.8), as opposed to the “no education” group; service and business as occupation (OR 2.9, CI 1.3-6.4; OR 3.7, CI 1.6-8.7, respectively); smoking history (OR 1.6, CI 0.99-2.5); and type 2 diabetes (OR 2.6 CI 1.5-4.3). Incomplete treatment (4.3; 95% CI 1.7-10.6), hospitalization for tuberculosis treatment (OR 16.9; CI 1.8-156.2), and adverse reaction (OR 8.2; 95% CI 3.2-20.7), are the factors related to previous tuberculosis treatment most likely to result in MDR-TB. Drug sensitive TB patients, who are seeking care from informal practitioners access care more promptly, but experience prolonged delay in initiating treatment, compared to those visiting qualified practitioners (p<0.05). Health system delay (time between visiting a provider and start of treatment) of MDR-TB patient was associated with the visit to private practitioners for first consultation, compared to visiting a DOTS centre (mean difference (days): 37.7; 95%; CI 15.0-60.4.1; p 0.003). Introduction of rapid diagnostic methods for MDR-TB has reduced the diagnosis time although some degree of delay was present in treatment initiation (median 5 and 10 days, respectively). Conclusion and recommendation: National Tuberculosis programmes should address identified risk factors in MDR-TB control strategy including previous tuberculosis treatment. Socio-demographic groups such as specific age-groups and people with some levels of education, who were associated with development of MDR-TB, could be addressed by the national TB control programme, through effective communication approach in preventing drug resistance. The integration of MDR-TB control activities with diabetes and tobacco control; engaging the private practitioners in MDR-TB control; and continued involvement of informal practitioners for early referral for diagnosis and treatment of TB, are needed in Bangladesh

Health system delay in treatment of multidrug resistant tuberculosis patients in Bangladesh

Background: Bangladesh is one of the 27 high burden countries for multidrug resistant tuberculosis listed by the World Health Organization. Delay in multidrug resistant tuberculosis treatment may allow progression of the disease and affect the attempts to curb transmission of drug resistant tuberculosis. The main objective of this study was to investigate the health system delay in multidrug resistant tuberculosis treatment in Bangladesh and to explore the factors related to the delay. Methods: Information related to the delay was collected as part of a previously conducted case-control study. The current study restricts analysis to patients with multidrug resistant tuberculosis who were diagnosed using rapid diagnostic methods (Xpert MTB/RIF or the line probe assay). Information was collected by face-to-face interviews and through record reviews from all three Government hospitals providing multidrug resistant tuberculosis services, from September 2012 to April 2013. Multivariable regression analysis was performed using Bootstrap variance estimators. Definitions were as follows: Provider delay: time between visiting a provider for first consultation on MDR-TB related symptom to visiting a designated diagnostic centre for testing; Diagnostic delay: time from date of diagnostic sample provided to date of result; Treatment initiation delay: time between the date of diagnosis and date of treatment initiation; Health system delay: time between visiting a provider to start of treatment. Health system delay was derived by adding provider delay, diagnostic delay and treatment initiation delay. Results: The 207 multidrug resistant tuberculosis patients experienced a health system delay of median 7.1 weeks. The health system delay consists of provider delay (median 4 weeks), diagnostic delay (median 5 days) and treatment initiation delay (median 10 days). Health system delay (Coefficient: 37.7; 95 %; CI 15.0-60.4; p 0.003) was associated with the visit to private practitioners for first consultation. Conclusions: Diagnosis time for multidrug resistant tuberculosis was fast using the rapid tests. However, some degree of delay was present in treatment initiation, after diagnosis. The most effective way to reduce health system delay would be through strategies such as engaging private practitioners in multidrug resistant tuberculosis control

Factors related to previous tuberculosis treatment of patients with multidrug-resistant tuberculosis in Bangladesh

Objective: Previous tuberculosis (TB) treatment status is an established risk factor for multidrug-resistant TB (MDR-TB). This study explores which factors related to previous TB treatment may lead to the development of multidrug resistant in Bangladesh. Design: We previously conducted a large case–control study to identify risk factors for developing MDR-TB in Bangladesh. Patients who had a history of previous TB treatment, either MDR-TB or non-MDR-TB, were interviewed about their previous treatment episode. This study restricts analysis to the strata of patients who have been previously treated for TB. Information was collected through face-to-face interviews and record reviews. Unadjusted and multivariable logistic regression was used for data analysis. Setting: Central-level, district-level and subdistrict-level hospitals in rural and urban Bangladesh. Results: The strata of previously treated patients include a total of 293 patients (245 current MDR-TB; 48 non-MDR-TB). Overall, 54% of patients received previous TB treatment more than once, and all of these patients were multidrug resistant. Patients with MDR-TB were more likely to have experienced the following factors: incomplete treatment (OR 4.3; 95% CI 1.7 to 10.6), adverse reactions due to TB treatment (OR 8.2; 95% CI 3.2 to 20.7), hospitalisation for symptoms associated with TB (OR 16.9; CI 1.8 to 156.2), DOTS (directly observed treatment, short-course) centre as treatment unit (OR 6.4; CI 1.8 to 22.8), supervised treatment (OR 3.8; CI 1.6 to 9.5); time-to-treatment centre (OR 0.984; CI 0.974 to 0.993). Conclusions: Incomplete treatment, hospitalisation for TB treatment and adverse reaction are the factors related to previous TB treatment of patients with MDR-TB. Although the presence of supervised treatment (DOT), less time-to-treatment centres and being treated in DOTS centres were relatively higher among the patients with MDR-TB compared with patients without MDR-TB, these findings include information of their most recent TB treatment episode only. Most (64.5%) of the patients with MDR-TB had received TB treatment more than once

From Mosques to Classrooms: Mobilizing the Community to Enhance Case Detection of Tuberculosis

In response to the global challenge of inadequate case detection of tuberculosis (TB), the Fund for Innovative DOTS Expansion through Local Initiatives to Stop Tuberculosis (FIDELIS) was developed in 2003 to rapidly assess and implement innovative approaches to increase the detection of new smear-positive TB cases. As previously reported, a wide range of target populations and interventions has been incorporated into successful FIDELIS projects

The association between daily 500 mg calcium supplementation and lower pregnancy-induced hypertension risk in Bangladesh

Abstract Background Evidence suggests that daily supplementation of 1500 to 2000 mg of calcium during pregnancy reduces pregnancy-induced hypertension (PIH). However, the evidence on the efficacy of low-dose calcium supplementation on PIH is limited. This paper assesses the longitudinal correlation between low-dose calcium intake (500 mg daily) and change in blood pressure during pregnancy among a homogeneous population in terms of hypertension and pre-eclampsia. Methods The study followed a retrospective cohort study design, and was carried out among 11,387 pregnant women from 10 rural upazilas (sub-districts) of Bangladesh where maternal nutrition initiative (MNI), implemented by Building Resources Across Communities (BRAC), was ongoing. The modified Poisson regression model was used to estimate the association (risk ratio) between consumption of calcium tablets and PIH. Results The present research found that women who consumed 500 mg/d calcium tablets for more than 6 months during their pregnancy had a 45% lower risk of developing hypertension compared to those who consumed less calcium (RR = 0.55, 95% CI = 0.33–0.93). Conclusions Daily supplementation of 500 mg oral calcium during pregnancy for at least 180 tablets is associated with a considerably reduced risk of PIH, but this study is unable to confirm whether this association is causal. The causal relationship needs to be confirmed through a large scale randomized controlled trial

Development of multidrug resistant tuberculosis in Bangladesh: a case-control study on risk factors

Objective: To determine the risk factors for developing multidrug resistant tuberculosis in Bangladesh. Methods: This case-control study was set in central, district and sub-district level hospitals of rural and urban Bangladesh. Included were 250 multidrug resistant tuberculosis (MDR-TB) patients as cases and 750 drug susceptible tuberculosis patients as controls. We recruited cases from all three government hospitals treating MDR-TB in Bangladesh during the study period. Controls were selected randomly from those local treatment units that had referred the cases. Information was collected through face-to-face interviews and record reviews. Unadjusted and multivariable logistic regression were used to analyse the data. Results: Previous treatment history was shown to be the major contributing factor to MDR-TB in univariate analysis. After adjusting for other factors in multivariable analysis, age group ‘‘18–25’’ (OR 1.77, CI 1.07–2.93) and ‘‘26–45’’ (OR 1.72, CI 1.12–2.66), some level of education (OR 1.94, CI 1.32–2.85), service and business as occupation (OR 2.88, CI 1.29–6.44; OR 3.71, CI 1.59–8.66, respectively), smoking history (OR 1.58, CI 0.99–2.5), and type 2 diabetes (OR 2.56 CI 1.51–4.34) were associated with MDR-TB. Previous treatment was not included in the multivariable analysis as it was correlated with multiple predictors. Conclusion: Previous tuberculosis treatment was found to be the major risk factor for MDR-TB. This study also identified age 18 to 45 years, some education up to secondary level, service and business as occupation, past smoking status, and type 2 diabetes as comorbid illness as risk factors. National Tuberculosis programme should address these risk factors in MDR-TB control strategy. The integration of MDR-TB control activities with diabetes and tobacco control programmes is needed in Bangladesh

Approaches of dengue control: vaccine strategies and future aspects

Dengue, caused by the dengue virus (DENV), affects millions of people worldwide every year. This virus has two distinct life cycles, one in the human and another in the mosquito, and both cycles are crucial to be controlled. To control the vector of DENV, the mosquito Aedes aegypti, scientists employed many techniques, which were later proved ineffective and harmful in many ways. Consequently, the attention shifted to the development of a vaccine; researchers have targeted the E protein, a surface protein of the virus and the NS1 protein, an extracellular protein. There are several types of vaccines developed so far, such as live attenuated vaccines, recombinant subunit vaccines, inactivated virus vaccines, viral vectored vaccines, DNA vaccines, and mRNA vaccines. Along with these, scientists are exploring new strategies of developing improved version of the vaccine by employing recombinant DNA plasmid against NS1 and also aiming to prevent the infection by blocking the DENV life cycle inside the mosquitoes. Here, we discussed the aspects of research in the field of vaccines until now and identified some prospects for future vaccine developments

Univariate logistic regression analysis on factors related to Multidrug Resistant Tuberculosis (MDR-TB).

a<p>Confidence interval at 95% level.</p>b<p>p is the p value of Wald test statistic.</p>c<p>‘Others’ subgroup under ‘Occupation’ includes housewife and self-employed small works.</p><p>Only the significant variables are shown in the table (significance level at 0.05).</p