In situ and ex situ bioremediation of heavy metals: the present scenario

Enhanced population growth, rapid industrialization, urbanization and hazardous industrial practices have resulted in the development of environmental pollution in the past few decades. Heavy metals are one of those pollutants that are related to environmental and public health concerns based on their toxicity. Effective bioremediation may be accomplished through “ex situ” and “in situ” processes, based on the type and concentration of pollutants, characteristics of the site but is not limited to cost. The recent developments in artificial neural network and microbial gene editing help to improve “in situ” bioremediation of heavy metals from the polluted sites. Multi-omics approaches are adopted for the effective removal of heavy metals by various indigenous microbes. This overview introspects two major bioremediation techniques, their principles, limitations and advantages, and the new aspects of nanobiotechnology, computational biology and DNA technology to improve the scenario

A home calendar and recall method of last menstrual period for estimating gestational age in rural Bangladesh: a validation study

Background: The best method of gestational age assessment is by ultrasound in the first trimester; however, this method is impractical in large field trials in rural areas. Our objective was to assess the validity of gestational age estimated from prospectively collected date of last menstrual period (LMP) using crown-rump length (CRL) measured in early pregnancy by ultrasound. Methods: As part of a large, cluster-randomized, controlled trial in rural Bangladesh, we collected dates of LMP by recall and as marked on a calendar every 5 weeks in women likely to become pregnant. Among those with a urinetest confirmed pregnancy, a subset with gestational age of <15 weeks (n = 353) were enrolled for ultrasound follow-up to measure CRL. We compared interview-assessed LMP with CRL gestational age estimates and classification of preterm, term, and post-term births. Results: LMP-based gestational age was higher than CRL by a mean (SD) of 2.8 (10.7) days; differences varied by maternal education and preterm birth (P < 0.05). Lin\u2019s concordance correlation coefficient was good at ultrasound [0.63 (95 % CI 0.56, 0.69)] and at birth [0.77 (95 % CI 0.73, 0.81)]. Validity of classifying preterm birth was high but post-term was lower, with specificity of 96 and 89 % and sensitivity of 86 and 67 %, respectively. Results were similar by parity. Conclusions: Prospectively collected LMP provided a valid estimate of gestational age and preterm birth in a rural, low-income setting and may be a suitable alternative to ultrasound in programmatic settings and large field trials. Trial registration: ClinicalTrials.gov NCT0086047

Filling the human resource gap through public-private partnership: Can private, community-based skilled birth attendants improve maternal health service utilization and health outcomes in a remote region of Bangladesh?

BACKGROUND:In Sunamganj there are fewer than four skilled providers per 10,000 population and just 27% of births are assisted by a skilled attendant. We evaluate a private community skilled birth attendant (P-CSBA) model, developed through the GSK-CARE Frontline Health Worker Programme, designed to address this gap and report on changes in service utilization and health outcomes from baseline to three years post-baseline. METHODS:This analysis presents the results of a pre-post cross sectional design. A baseline survey (n = 1800) was conducted using a multistage cluster sampling approach. Three years post-baseline a second cross-sectional survey (n = 1755) was conducted across the same project area. To describe demographic characteristics of the study participants descriptive statistical techniques were used as appropriate. Logistic and multiple logistic regression, controlling for a comprehensive set of covariates, were used to assess odds ratios for key maternal health behaviors and outcomes. RESULTS:Birth planning and the use of key maternal health services improved from baseline to follow-up. There was a dramatic increase in the proportion of respondents reporting skilled attendance at birth (aOR: 2.18, p = .001). Women also reported significantly fewer complications during the prenatal (aOR: .30, p<.001), labor and delivery (aOR: 0.41, p<.0001) and postnatal periods (aOR: 0.32, p<.0001). CONCLUSION:Private-sector approaches, when coupled with robust efforts to strengthen and collaborate with the public sector, can work successfully to deliver services in underserved communities. The success of this model lends credence to the growing appreciation that reaching our development targets will require governments to work in partnership with private sector actors and highlights the potential of private-public partnerships as we drive towards universal health coverage

Newborn physical condition and breastfeeding behaviours: Secondary outcomes of a cluster‐randomized trial of prenatal lipid‐based nutrient supplements in Bangladesh

Prenatal nutritional supplements may improve birth outcomes. This study aims to examine the effect of prenatal lipid-based nutrient supplements (LNS), compared with iron and folic acid (IFA), on general newborn physical condition and feeding behaviours. We conducted a cluster-randomized effectiveness trial that enrolled 4,011 pregnant women at ≤20 gestational weeks. LNS and IFA were provided to women in 48 and 16 clusters, respectively, for daily consumption until delivery. We collected data on household socio-economic, food insecurity, and maternal characteristics during early pregnancy and on newborn condition and feeding within 72&nbsp;hr of delivery. We analysed intervention effects on these secondary outcomes using mixed models with analysis of covariance for continuous outcomes and logistic regression for dichotomous outcomes. Among 3,664 live births, intervention groups did not differ in newborn response, mother's rating of the general condition of her newborn, early initiation of breastfeeding (EIBF), suckling ability, or frequency and exclusivity of breastfeeding in the first 24&nbsp;hr. If the mother perceived her infant to be healthy, EIBF was more likely (OR [95% CI]: 2.08 [1.46, 2.97]) and frequency of breastfeeding in the first 24&nbsp;hr was greater (mean difference [95% CI]: 3.0 [1.91, 4.01]), but there was no difference in exclusive breastfeeding in the first 24&nbsp;hr. Newborn condition and early breastfeeding practices were not affected by giving mothers prenatal LNS versus IFA. However, early breastfeeding practices were related to maternal perception of her newborn's condition. Thus, interventions to improve breastfeeding practices for newborns with poorer perceived health status may be useful

Factors associated with diarrhea and acute respiratory infection in children under two years of age in rural Bangladesh.

BackgroundDiarrhea and acute respiratory infection (ARI) are major causes of child mortality. We aimed to identify risk factors associated with diarrhea and ARI among children under 2 years of age in rural northern Bangladesh.MethodWe collected information on diarrhea and ARI in the previous 14 days and the previous 6 months at 6, 12, 18 and 24 months of age as part of a longitudinal, cluster randomized effectiveness trial, the Rang-Din Nutrition Study which enrolled 4011 pregnant women at ≤20 gestational weeks. Women and their children were followed up until 2 years postpartum. Information on household socioeconomic status, type of toilet, garbage disposal system, food insecurity, number of under-five children in the household, type of family, maternal characteristics and child characteristics was collected at baseline and/or at 6, 12, 18 and 24 months postpartum. Data on newborn health and feeding behaviors were collected within 72 h of delivery. Associations between potential risk factors and morbidity prevalence outcomes were assessed using logistic regression controlling for potential confounders.ResultsOut of 3664 live born children, we collected information from ~ 3350 children at 6, 12, 18 and 24 months of age. Diarrhea in the previous 14 days, and in the previous 6 months, was associated with maternal depression score and food insecurity; diarrhea in the previous 6 months was also associated with family type (nuclear vs. joint). ARI in the previous 14 days was associated with maternal depression score, type of toilet and garbage disposal, household food insecurity and sex. Cough or nasal discharge in the past 6 months was associated with maternal depression score, type of toilet and garbage disposal, household food insecurity, sex and perceived overall physical condition of the infant after birth.ConclusionMaternal depression and food insecurity appear to be important risk factors for diarrhea and respiratory infection among children under 2 years of age in this setting. These findings suggest that policies and programs that include strategies to address maternal mental health and household food insecurity may contribute to improved child health.Trial registrationThe trial was registered with the US National Institutes of Health at ClinicalTrials.gov, # NCT01715038 , with registration completed October 26, 2012

Major dietary patterns and carotid intima-media thickness in Bangladesh

OBJECTIVE: Carotid intima media thickness (IMT) is a validated surrogate marker of preclinical atherosclerosis and is predictive of cardiovascular morbidity and mortality. Research on the association between IMT and diet, however, is lacking, especially in low-income countries or low-BMI populations. DESIGN: Cross-sectional analysis. Dietary intakes were measured using a validated, 39-item food-frequency questionnaire at baseline cohort recruitment. IMT measurements were obtained from 2010–2011. SETTING: Rural Bangladesh. SUBJECTS: 1149 participants randomly selected from the Health Effects of Arsenic Longitudinal Study, an ongoing, population-based, prospective cohort study established in 2000. Average age at IMT measurement was 45.5 years. RESULTS: Principal component analysis of reported food items yielded a “balanced” diet, an “Animal protein” diet, and a “gourd and root vegetable” diet. We observed a positive association between the gourd/root vegetable diet and IMT, as each standard deviation increase in pattern adherence was related to a difference of 7.74 μm (95% CI: 2.86, 12.62; P<0.01) in IMT, controlling for age, sex, total caloric intake, smoking status, BMI, systolic blood pressure, and diabetes mellitus diagnoses. The balanced pattern was associated with lower IMT (−4.95 μm for each standard deviation of adherence [95% CI: −9.78, −0.11; P=0.045]). CONCLUSIONS: A gourd/root vegetable diet in this Bangladeshi population positively correlated with carotid IMT, while a balanced diet is associated with decreased IMT

Arsenic Exposure From Drinking Water, Arsenic Methylation Capacity, and Carotid Intima-Media Thickness in Bangladesh

We conducted a cross-sectional study to evaluate the interrelationships between past arsenic exposure, bio-markers specific for susceptibility to arsenic exposure, and carotid intima-media thickness (cIMT) in 959 subjects from the Health Effects of Arsenic Longitudinal Study in Bangladesh. We measured cIMT levels on average 7.2 years after baseline during 2010–2011. Arsenic exposure was measured in well water at baseline and in urine sam-ples collected at baseline and during follow-up. Every 1-standard-deviation increase in urinary arsenic (357.9 µg/g creatinine) and well-water arsenic (102.0 µg/L) concentration was related to a 11.7-µm (95 % confidence interval (CI): 1.8, 21.6) and 5.1-µm (95 % CI: −0.2, 10.3) increase in cIMT, respectively. For every 10 % increase in mono-methylarsonic acid (MMA) percentage, therewas an increase of 12.1 µm (95%CI: 0.4, 23.8) in cIMT. Among partici-pants with a higher urinary MMA percentage, a higher ratio of urinary MMA to inorganic arsenic, and a lower ratio of dimethylarsinic acid to MMA, the association between well-water arsenic and cIMT was stronger. The findings indicate an effect of past long-term arsenic exposure on cIMT, which may be potentiated by suboptimal or incom-plete arsenic methylation capacity. Future prospective studies are needed to confirm the association between arse-nic methylation capacity and atherosclerosis-related outcomes. arsenic; Bangladesh; cardiovascular diseases; carotid intima-media thickness; drinking wate

Interaction between arsenic exposure from drinking water and genetic susceptibility in carotid intima–media thickness in Bangladesh

Epidemiologic studies that evaluated genetic susceptibility to the effects of arsenic exposure from drinking water on subclinical atherosclerosis are limited. We conducted a cross-sectional study of 1,078 participants randomly selected from the Health Effects of Arsenic Longitudinal Study in Bangladesh to evaluate whether the association between arsenic exposure and carotid artery intima-medial thickness (cIMT) differs by 207 single-nucleotide polymorphisms (SNPs) in 18 genes related to arsenic metabolism, oxidative stress, inflammation, and endothelial dysfunction. Although not statistically significant after correcting for multiple testing, nine SNPs in APOE, AS3MT, PNP, and TNF genes had a nominally statistically significant interaction with well-water arsenic in cIMT. For instance, the joint presence of a higher level of well-water arsenic (≥ 40.4 μg/L) and the GG genotype of AS3MT rs3740392 was associated with a difference of 40.9 μm (95% CI = 14.4, 67.5) in cIMT, much greater than the difference of cIMT associated with the genotype alone (β = -5.1 μm, 95% CI = -31.6, 21.3) or arsenic exposure alone (β = 7.2 μm, 95% CI = -3.1, 17.5). The pattern and magnitude of the interactions were similar when urinary arsenic was used as the exposure variable. Additionally, the at-risk genotypes of the AS3MT SNPs were positively related to proportion of monomethylarsonic acid (MMA) in urine, which is indicative of arsenic methylation capacity. The findings provide novel evidence that genetic variants related to arsenic metabolism may play an important role in arsenic-induced subclinical atherosclerosis. Future replication studies in diverse populations are needed to confirm the findings