Artificial intelligence and visual inspection in cervical cancer screening.

INTRODUCTION: Visual inspection with acetic acid is limited by subjectivity and a lack of skilled human resource. A decision support system based on artificial intelligence could address these limitations. We conducted a diagnostic study to assess the diagnostic performance using visual inspection with acetic acid under magnification of healthcare workers, experts, and an artificial intelligence algorithm. METHODS: A total of 22 healthcare workers, 9 gynecologists/experts in visual inspection with acetic acid, and the algorithm assessed a set of 83 images from existing datasets with expert consensus as the reference. Their diagnostic performance was determined by analyzing sensitivity, specificity, and area under the curve, and intra- and inter-observer agreement was measured using Fleiss kappa values. RESULTS: Sensitivity, specificity, and area under the curve were, respectively, 80.4%, 80.5%, and 0.80 (95% CI 0.70 to 0.90) for the healthcare workers, 81.6%, 93.5%, and 0.93 (95% CI 0.87 to 1.00) for the experts, and 80.0%, 83.3%, and 0.84 (95% CI 0.75 to 0.93) for the algorithm. Kappa values for the healthcare workers, experts, and algorithm were 0.45, 0.68, and 0.63, respectively. CONCLUSION: This study enabled simultaneous assessment and demonstrated that expert consensus can be an alternative to histopathology to establish a reference standard for further training of healthcare workers and the artificial intelligence algorithm to improve diagnostic accuracy.

Pharmacological Features of 18ß-Glycyrrhetinic Acid: A Pentacyclic Triterpenoid of Therapeutic Potential.

Glycyrrhiza glabra L. (belonging to the family Leguminosae), commonly known as Licorice, is a popular medicinal plant that has been used in traditional medicine worldwide for its ethnopharmacological efficacy in treating several ailments. Natural herbal substances with strong biological activity have recently received much attention. The main metabolite of glycyrrhizic acid is 18ß-glycyrrhetinic acid (18ßGA), a pentacyclic triterpene. A major active plant component derived from licorice root, 18ßGA has sparked a lot of attention due to its pharmacological properties. The current review thoroughly examines the literature on 18ßGA, a major active plant component obtained from Glycyrrhiza glabra L. The current work provides insight into the pharmacological activities of 18ßGA and the potential mechanisms of action involved. The plant contains a variety of phytoconstituents such as 18ßGA, which has a variety of biological effects including antiasthmatic, hepatoprotective, anticancer, nephroprotective, antidiabetic, antileishmanial, antiviral, antibacterial, antipsoriasis, antiosteoporosis, antiepileptic, antiarrhythmic, and anti-inflammatory, and is also useful in the management of pulmonary arterial hypertension, antipsychotic-induced hyperprolactinemia, and cerebral ischemia. This review examines research on the pharmacological characteristics of 18ßGA throughout recent decades to demonstrate its therapeutic potential and any gaps that may exist, presenting possibilities for future drug research and development.

Effect of short-term educational intervention on complementary feeding index among infants in rural Bangladesh: a randomized control trial.

BACKGROUND: Timely, adequate and appropriate Complementary Feeding (CF) is essential for the growth and cognitive development of infants, but until today, evidence-based information is scarce in terms of impact evaluation of CF index (CFI). The study aimed to examine the effect of the short-term intervention of promoting CF practices on the nutritional status of infants in rural Bangladesh. METHODS: An educational-intervention study followed a randomized controlled trial (RCT) design (NCT03024710). Mothers and family members in the intervention arm received intensive counselling on CF through community health workers (CHWs), whereas existing healthcare services were received in the comparison arm. The study was carried out in the rural Matlab sub-district of Bangladesh between April 2011 and March 2013. In the specified study areas among 360 mother-infant pairs systematically assigned into intervention group and comparison group. Short-term educational intervention on CF was provided for the intervention group and existing services were un-intervened for the comparison group. The outcome of interventions was evaluated after the implementation period using Generalized equation estimation model. RESULTS: At baseline, the study participants were not different except mean height (p = 0.04), weight-for-age Z score (WAZ) (p = 0.03) and religion (p = 0.04) in between two groups. The mean CFI was significantly higher at intervention area than the comparison and higher category of CFI (score 10 or more) was significantly higher at intervention area than comparison. After adjustment, one-unit CFI increased height-for-age z score by 0.07 units and decreased WAZ by 0.13 units in the intervention group but not significantly changed observed at comparison group. CONCLUSION: Guided short-term nutritional intervention and developed CFI indicated a significantly better score in intervention area than comparison groups and would be a well adaptable tool for future studies. TRIAL REGISTRATION: The trial was registered ( NCT03024710 ) at clinical trial registration website. Date of registration: 1/19/2017. Name of the registry: Clinical Trial.gov. Date of registration: 19/1/2017 (retrospective registered). URL of trial: https://clinicaltrials.gov/ct2/show/NCT03024710.

Investigating feasibility of 2021 WHO protocol for cervical cancer screening in underscreened populations: PREvention and SCReening Innovation Project Toward Elimination of Cervical Cancer (PRESCRIP-TEC).

BACKGROUND: High-risk human papillomavirus (hrHPV) testing has been recommended by the World Health Organization as the primary screening test in cervical screening programs. The option of self-sampling for this screening method can potentially increase women's participation. Designing screening programs to implement this method among underscreened populations will require contextualized evidence. METHODS: PREvention and SCReening Innovation Project Toward Elimination of Cervical Cancer (PRESCRIP-TEC) will use a multi-method approach to investigate the feasibility of implementing a cervical cancer screening strategy with hrHPV self-testing as the primary screening test in Bangladesh, India, Slovak Republic and Uganda. The primary outcomes of study include uptake and coverage of the screening program and adherence to follow-up. These outcomes will be evaluated through a pre-post quasi-experimental study design. Secondary objectives of the study include the analysis of client-related factors and health system factors related to cervical cancer screening, a validation study of an artificial intelligence decision support system and an economic evaluation of the screening strategy. DISCUSSION: PRESCRIP-TEC aims to provide evidence regarding hrHPV self-testing and the World Health Organization's recommendations for cervical cancer screening in a variety of settings, targeting vulnerable groups. The main quantitative findings of the project related to the impact on uptake and coverage of screening will be complemented by qualitative analyses of various determinants of successful implementation of screening. The study will also provide decision-makers with insights into economic aspects of implementing hrHPV self-testing, as well as evaluate the feasibility of using artificial intelligence for task-shifting in visual inspection with acetic acid. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05234112 . Registered 10 February 2022.

Organophosphorus insecticides mineralizing endophytic and rhizospheric soil bacterial consortium influence eggplant growth-promotion.

This study was aimed to evaluate eggplant's growth-enhancing activity of chlorpyrifos and diazinon-degrading endophytic and rhizospheric soil bacteria isolated from cauliflower and tomato roots and the rhizospheric soil of rice roots, respectively. The identified endophytes belong to the Acinetobacter, Enterobacter and Klebsiella genera, while rhizospheric soil isolates belong to Pantoea, Acinetobacter, Kosakonia, Morganella, Enterobacter, and Klebsiella genera with species variation and genetic distances. All the strain's consumed 100% (50 mg/5 mL) chlorpyrifos and diazinon after 14 days of exposure, except for Pantoea sp. HSTU-Sny4 (84%) and Kosakonia sp. HSTU-ASn39 (42%). The strain's exhibited N-fixation, P-solubilization, indole-3-acetic acid (IAA), and ACC-deaminase production capabilities. The individual strain's and consortium treatment enhanced eggplant growth at germination, seedling, vegetative and reproductive stages. Plant growth-promoting genes, e.g., nif-cluster, chemotaxis, phosphates, sulfur, abiotic stress, chemotaxis, biofilm formation and organophosphorus insecticide-degrading genes were annotated in Klebsiella sp. HSTU-Sny5 and Morganella sp. HSTU-ASny43 genomes. Importantly, the mixed consortium supplemented with 40% urea-treated eggplants demonstrated similar growth parameters compared to the 100% urea eggplants. Plenty of insecticide-degrading proteins belonged to HSTU-Sny5 and HSTU-ASny43 strain's and had interacted with 100 different insecticides as confirmed in virtual screening. This research has a significant role in reducing the application of chemical fertilizer and bioremediation of pesticides in agriculture.

Diagnostic Accuracy of Detecting Diabetic Retinopathy by Using Digital Fundus Photographs in the Peripheral Health Facilities of Bangladesh: Validation Study.

BACKGROUND: Diabetic retinopathy can cause blindness even in the absence of symptoms. Although routine eye screening remains the mainstay of diabetic retinopathy treatment and it can prevent 95% of blindness, this screening is not available in many low- and middle-income countries even though these countries contribute to 75% of the global diabetic retinopathy burden. OBJECTIVE: The aim of this study was to assess the diagnostic accuracy of diabetic retinopathy screening done by non-ophthalmologists using 2 different digital fundus cameras and to assess the risk factors for the occurrence of diabetic retinopathy. METHODS: This validation study was conducted in 6 peripheral health facilities in Bangladesh from July 2017 to June 2018. A double-blinded diagnostic approach was used to test the accuracy of the diabetic retinopathy screening done by non-ophthalmologists against the gold standard diagnosis by ophthalmology-trained eye consultants. Retinal images were taken by using either a desk-based camera or a hand-held camera following pupil dilatation. Test accuracy was assessed using measures of sensitivity, specificity, and positive and negative predictive values. Overall agreement with the gold standard test was reported using the Cohen kappa statistic (κ) and area under the receiver operating curve (AUROC). Risk factors for diabetic retinopathy occurrence were assessed using binary logistic regression. RESULTS: In 1455 patients with diabetes, the overall sensitivity to detect any form of diabetic retinopathy by non-ophthalmologists was 86.6% (483/558, 95% CI 83.5%-89.3%) and the specificity was 78.6% (705/897, 95% CI 75.8%-81.2%). The accuracy of the correct classification was excellent with a desk-based camera (AUROC 0.901, 95% CI 0.88-0.92) and fair with a hand-held camera (AUROC 0.710, 95% CI 0.67-0.74). Out of the 3 non-ophthalmologist categories, registered nurses and paramedics had strong agreement with kappa values of 0.70 and 0.85 in the diabetic retinopathy assessment, respectively, whereas the nonclinical trained staff had weak agreement (κ=0.35). The odds of having retinopathy increased with the duration of diabetes measured in 5-year intervals (P<.001); the odds of having retinopathy in patients with diabetes for 5-10 years (odds ratio [OR] 1.81, 95% CI 1.37-2.41) and more than 10 years (OR 3.88, 95% CI 2.91-5.15) were greater than that in patients with diabetes for less than 5 years. Obesity was found to have a negative association (P=.04) with diabetic retinopathy. CONCLUSIONS: Digital fundus photography is an effective screening tool with acceptable diagnostic accuracy. Our findings suggest that diabetic retinopathy screening can be accurately performed by health care personnel other than eye consultants. People with more than 5 years of diabetes should receive priority in any community-level retinopathy screening program. In a country like Bangladesh where no diabetic retinopathy screening services exist, the use of hand-held cameras can be considered as a cost-effective option for potential system-wide implementation.

Tumor ablation due to inhomogeneous anisotropic diffusion in generic three-dimensional topologies.

In recent decades computer-aided technologies have become prevalent in medicine, however, cancer drugs are often only tested on in vitro cell lines from biopsies. We derive a full three-dimensional model of inhomogeneous -anisotropic diffusion in a tumor region coupled to a binary population model, which simulates in vivo scenarios faster than traditional cell-line tests. The diffusion tensors are acquired using diffusion tensor magnetic resonance imaging from a patient diagnosed with glioblastoma multiform. Then we numerically simulate the full model with finite element methods and produce drug concentration heat maps, apoptosis hotspots, and dose-response curves. Finally, predictions are made about optimal injection locations and volumes, which are presented in a form that can be employed by doctors and oncologists.

Investigating the process of evidence-informed health policymaking in Bangladesh: a systematic review.

Over the last four decades, Bangladesh has made considerable improvements in population health, this is in part due to the use of evidence to inform policymaking. This systematic review aims to better understand critical factors that have facilitated the diffusion of scientific evidence into multiple phases of health policymaking in Bangladesh. To do this an existing policy framework designed by Shiffman and Smith in 2007, was used to extract and synthesize data from selected policy analyses. This framework was used to ensure the content, context and actors involved with evidence-informed policymaking were considered in each case where research had helped shape a health policy. The 'PRISMA Checklist' was employed to design pre-specified eligibility criteria for the selection of information sources, search strategy, inclusion and exclusion criteria, and process of data extraction and synthesis. Through our systematic search conducted from February to May 2017, we initially identified 1859 articles; after removal of duplicates, followed by the screening of titles, abstracts and full-texts, 24 articles were included in the analysis. Health policy issues included the following topics: maternal and child health, tobacco control, reproductive health, infectious disease control and the impact and sustainability of knowledge translation platforms. Findings suggested that research evidence that could be used to meet key targets associated with the Millennium Development Goals (MDGs) were more likely to be considered as a political (and therefore policy) priority. Furthermore, avenues of engagement between research organizations and the government as well as collective action from civil-society organizations were important for the diffusion of evidence into policies. Through this article, it is apparent that the interface between evidence and policy formulation occurs when evidence is, disseminated by a cohesive policy-network with strong leadership and framed to deliver solutions for problems on both the domestic and global development agenda.

Recursive model for dose-time responses in pharmacological studies.

BACKGROUND: Clinical studies often track dose-response curves of subjects over time. One can easily model the dose-response curve at each time point with Hill equation, but such a model fails to capture the temporal evolution of the curves. On the other hand, one can use Gompertz equation to model the temporal behaviors at each dose without capturing the evolution of time curves across dosage. RESULTS: In this article, we propose a parametric model for dose-time responses that follows Gompertz law in time and Hill equation across dose approximately. We derive a recursion relation for dose-response curves over time capturing the temporal evolution and then specify a regression model connecting the parameters controlling the dose-time responses with individual level proteomic data. The resultant joint model allows us to predict the dose-response curves over time for new individuals. CONCLUSION: We have compared the efficacy of our proposed Recursive Hybrid model with individual dose-response predictive models at desired time points. We note that our proposed model exhibits a superior performance compared to the individual ones for both synthetic data and actual pharmacological data. For the desired dose-time varying genetic characterization and drug response values, we have used the HMS-LINCS database and demonstrated the effectiveness of our model for all available anticancer compounds.

Non-pharmacological interventions for the prevention of hypertension in low-income and middle-income countries: protocol for a systematic review and meta-analysis.

INTRODUCTION: In recent times, hypertension has become one of the major public health concerns in both the developed and the developing world and is responsible for death due to heart diseases and stroke. The increasing trend of the prevalence of hypertension in low-income and middle-income countries (LMICs) and it's catastrophic consequences have made the phenomenon important to continue to investigate interventions for its prevention and control. Different dietary and lifestyle-related approaches have been recommended for the prevention of hypertension. The aim of this proposed review is to explore the available non-pharmacological interventions tried for the prevention of hypertension in LMICs. METHODS AND ANALYSIS: Eight electronic databases will be searched covering the period between 1990 and 2016 to identify relevant studies and will be screened by two independent reviewers. The searched articles will be included for full-text extraction applying definitive inclusion and exclusion criteria. Appropriate critical appraisal tools including the Cochrane Handbook for Systematic Reviews of Interventions will be used to assess the risk of bias. Disagreement between the two reviewers will be resolved by a third reviewer. Narrative synthesis of the findings will be provided along with summaries of the intervention effect. A meta-analysis will be undertaken using the random-effects model where applicable. Heterogeneity between the studies will be assessed, and sensitivity analysis will be conducted based on study quality. ETHICS AND DISSEMINATION: Approval from the institutional review board has been taken for this review. Findings will be summarised in a single manuscript.This review is an attempt to explore the available non-pharmacological approaches for the prevention of hypertension in LMICs. Findings from the review will highlight effective non-pharmacological measures for the prevention of hypertension to guide policy for future strategies. PROSPERO REGISTRATION NUMBER: CRD42017055423.

Inflammatory back pain and associated disease conditions among patients with chronic low back pain in Bangladesh.

AIM: Inflammatory back pain (IBP) is the earliest symptom of axial and other forms of spondyloarthritis (SpA). However, there are no published data on prevalence of IBP among patients suffering from chronic low back pain (CLBP) in Bangladesh. In this study, we estimated the prevalence of IBP and the subtypes of SpA in a tertiary hospital in Bangladesh. METHODS: This 1 year cross-sectional study was conducted among 240 CLBP patients in a rheumatology outpatient clinic. Assessment of Spondyloarthritis International Society classification criteria of IBP and predefined recognized classification criteria were followed to define different subtypes of SpA. Means and standard deviations were reported for continuous variables. Descriptive and bi-variate analyses were accordingly performed. RESULTS: Of 240 CLBP patients, 60 (25%) had IBP and 180 (75%) had mechanical back pain (MBP). Among the 60 IBP patients, 52 (86.6%) had predominantly axial SpA (axSpA) and eight (13.4%) had predominantly peripheral spondyloarthritis. In the axSpA group, 49 (94.2%) had radiographic axSpA (rd-axSpA) also known as AS and three (5.8%) had non-radiographic axSpA (nr-axspA). AxSpA patients could be divided into eight (15.35%) with psoriasis, two (3.8%) with reactive arthritis and one patient (1.9%) had arthritis associated with inflammatory bowel disease. Fifty (83.3%) IBP and 73 (40.6%) MBP patients had age at onset of back pain < 40 years. Forty-two (70%) of the IBP and 100 (55.6%) of the MBP patients had normal body mass index. All these differences were statistically significant (P ≤ 0.0001). CONCLUSIONS: Inflammatory back pain is common among patients presenting with CLBP. The commonest cause of IBP is AS, followed by PsA and nr-axSpA.

Phytoremediation of arsenic from the contaminated soil using transgenic tobacco plants expressing ACR2 gene of Arabidopsis thaliana.

We have cloned, characterized and transformed the AtACR2 gene (arsenic reductase 2) of Arabidopsis thaliana into the genome of tobacco (Nicotiana tabacum, var Sumsun). Our results revealed that the transgenic tobacco plants are more tolerant to arsenic than the wild type ones. These plants can grow on culture medium containing 200µM arsenate, whereas the wild type can barely survive under this condition. Furthermore, when exposed to 100µM arsenate for 35days the amount of arsenic accumulated in the shoots of transgenic plants was significantly lower (28µg/g d wt.) than that found in the shoots of non-transgenic controls (40µg/g d wt.). However, the arsenic content in the roots of transgenic plants was significantly higher (2400µg/g d. wt.) than that (2100µg/g d. wt.) observed in roots of wild type plants. We have demonstrated that Arabidopsis thaliana AtACR2 gene is a potential candidate for genetic engineering of plants to develop new crop cultivars that can be grown on arsenic contaminated fields to reduce arsenic content of the soil and can become a source of food containing no arsenic or exhibiting substantially reduced amount of this metalloid.

Identification of a Natural Killer Cell Receptor Allele That Prolongs Survival of Cytomegalovirus-Positive Glioblastoma Patients.

By affecting immunological presentation, the presence of cytomegalovirus in some glioblastomas may impact progression. In this study, we examined a hypothesized role for natural killer (NK) cells in impacting disease progression in this setting. We characterized 108 glioblastoma patients and 454 healthy controls for HLA-A,-B,-C, NK-cell KIR receptors, and CMV-specific antibodies and correlated these metrics with clinical parameters. Exome sequences from a large validation set of glioblastoma patients and control individuals were examined from in silico databases. We demonstrated that the KIR allele KIR2DS4*00101 was independently prognostic of prolonged survival. KIR2DS4*00101 displayed 100% concordance with cognate HLA-C1 ligands in glioblastoma patients, but not controls. In the context of both HLA-C1/C2 ligands for the KIR2DS4 receptor, patient survival was further extended. Notably, all patients carrying KIR2DS4*00101 alleles were CMV seropositive, but not control individuals, and exhibited increased NK-cell subpopulations, which expressed the cytotoxicity receptors CD16, NKG2D, and CD94/NKG2C. Finally, healthy controls exhibited a reduced risk for developing glioblastoma if they carried two KIR2DS4*00101 alleles, where protection was greatest among Caucasian individuals. Our findings suggest that KIR2DS4*00101 may offer a molecular biomarker to identify intrinsically milder forms of glioblastoma. Cancer Res; 76(18); 5326-36. ©2016 AACR.

Elevated concentrations of serum matrix metalloproteinase-2 and -9 and their associations with circulating markers of cardiovascular diseases in chronic arsenic-exposed individuals.

BACKGROUND: Cardiovascular diseases (CVDs) and cancers are the major causes of chronic arsenic exposure-related morbidity and mortality. Matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) are deeply involved in the pathogenesis of CVDs and cancers. This study has been designed to evaluate the interactions of arsenic exposure with serum MMP-2 and MMP-9 concentrations especially in relation to the circulating biomarkers of CVDs. METHODS: A total of 373 human subjects, 265 from arsenic-endemic and 108 from non-endemic areas in Bangladesh were recruited for this study. Arsenic concentrations in the specimens were measured by inductively coupled plasma mass spectroscopy (ICP-MS) and serum MMPs were quantified by immunoassay kits. RESULTS: Serum MMP-2 and MMP-9 concentrations in arsenic-endemic population were significantly (p < 0.001) higher than those in non-endemic population. Both MMPs showed significant positive interactions with drinking water (r s = 0.208, p < 0.001 for MMP-2; r s = 0.163, p < 0.01 for MMP-9), hair (r s = 0.163, p < 0.01 for MMP-2; r s = 0.173, p < 0.01 for MMP-9) and nail (r s = 0.160, p < 0.01 for MMP-2; r s = 0.182, p < 0.001 for MMP-9) arsenic of the study subjects. MMP-2 concentrations were 1.02, 1.03 and 1.05 times, and MMP-9 concentrations were 1.03, 1.06 and 1.07 times greater for 1 unit increase in log-transformed water, hair and nail arsenic concentrations, respectively, after adjusting for covariates (age, sex, BMI, smoking habit and hypertension). Furthermore, both MMPs were increased dose-dependently when the study subjects were split into three (≤10, 10.1-50 and > 50 µg/L) groups based on the regulatory upper limit of water arsenic concentration set by WHO and Bangladesh Government. MMPs were also found to be significantly (p < 0.05) associated with each other. Finally, the concentrations of both MMPs were correlated with several circulating markers related to CVDs. CONCLUSIONS: This study showed the significant positive associations and dose-response relationships of arsenic exposure with serum MMP-2 and MMP-9 concentrations. This study also showed the interactions of MMP-2 and MMP-9 concentrations with the circulating markers of CVDs suggesting the MMP-2 and MMP-9 -mediated mechanism of arsenic-induced CVDs.

Diarrhoea and smoking: an analysis of decades of observational data from Bangladesh.

BACKGROUND: Although cigarette smoking affects all biological systems of the human body including the gastrointestinal tract, there is a lack of evidence regarding its effect on the severity of diarrhoeal disease and whether a dose-response relationship exists. We therefore tested for the presence of specific causative pathogens for infectious diarrhoea, assessed the independent effect of smoking on its severity and tested whether any dose-response relationship existed while controlling for subjects' age, sociodemographic characteristics and presence of causative pathogens in an urban setting in Bangladesh. METHODS: A total of 20,757 patients aged 15 years and above with diarrhoea were enrolled into the Diarrhoeal Disease Surveillance System, managed by the International Centre for Diarrhoeal Disease Research, Bangladesh, from 1993 to 2012. We collected data on individuals' current daily consumption of cigarettes and bidis (traditional hand-rolled cigarettes) and conducted an ordered logistic regression to determine the effect of smoking on diarrhoeal disease severity and whether a dose-response relationship exists. RESULTS: We identified 19 % of patients with diarrhoea as smokers, of whom 52 % smoked 1-9 cigarettes per day. While 97 % of smokers were male, 41 % were aged 15-30 years of age. Smokers were found to have a significantly lower severity of diarrhoeal disease (OR: 0.92, 95 % CI: 0.85-0.99, p = 0.025) after adjusting for age, wealth quintile, illiteracy and the presence of specific causative pathogens (Vibrio cholerae and Shigella). We observed no dose-response relationship between the number of cigarettes smoked per day and disease severity when adjusting for the same covariates. Smokers were more frequently infected with Shigella (7 vs. 6 %, p < 0.001) and less often with Vibrio cholerae (22 vs. 26 %, p < 0.001) than their non-smoking counterparts. CONCLUSIONS: The aetiology and severity of diarrhoeal disease differed between smokers and non-smokers in our sample. However, we found no dose-response relationship between disease severity and the number of cigarettes smoked per day.

In silico and in vivo studies of molecular structures and mechanisms of AtPCS1 protein involved in binding arsenite and/or cadmium in plant cells.

This paper reports a continuation of our previous research on the phytochelatin synthase1 (PCS1) gene involved in binding and sequestration of heavy metals or metalloids in plant cells. Construction of a 3D structure of the Arabidopsis thaliana PCS1 protein and prediction of gene function by employing iterative implementation of the threading assembly refinement (I-TASSER) revealed that PC ligands (3GC-gamma-glutamylcysteine) and Gln50, Pro53, Ala54, Tyr55, Cys56, Ile102, Gly161, His162, Phe163, Asp204 and Arg211 residues are essential for formation of chelating complex with cadmium (Cd²âº) or arsenite (AsIII). This finding suggests that the PCS1 protein might be involved in the production of the enzyme phytochelatin synthase, which might in turn bind, localize, store or sequester heavy metals in plant cells. For validation of the in silico results, we included a T-DNA tagged mutant of Arabidopsis thaliana, SAIL_650_C12, (mutation in AtPCS1 gene) in our investigation. Furthermore, using reverse transcriptase PCR we confirmed that the mutant does not express the AtPCS1 gene. Mutant plants of SAIL_650_C12 were exposed to various amounts of cadmium (Cd²âº) and arsenite (AsIII) and the accumulation of these toxic metals in the plant cells was quantified spectrophotometrically. The levels of Cd²âº and AsIII accumulation in the mutant were approximately 2.8 and 1.6 times higher, respectively, than that observed in the wild-type controlled plants. We confirmed that the results obtained in in silico analyses complement those obtained in in vivo experiments.

Association between arsenic exposure and plasma cholinesterase activity: a population based study in Bangladesh.

BACKGROUND: Arsenic is a potent pollutant that has caused an environmental catastrophe in certain parts of the world including Bangladesh where millions of people are presently at risk due to drinking water contaminated by arsenic. Chronic arsenic exposure has been scientifically shown as a cause for liver damage, cancers, neurological disorders and several other ailments. The relationship between plasma cholinesterase (PChE) activity and arsenic exposure has not yet been clearly documented. However, decreased PChE activity has been found in patients suffering liver dysfunction, heart attack, cancer metastasis and neurotoxicity. Therefore, in this study, we evaluated the PChE activity in individuals exposed to arsenic via drinking water in Bangladesh. METHODS: A total of 141 Bangladeshi residents living in arsenic endemic areas with the mean arsenic exposure of 14.10 +/- 3.27 years were selected as study subjects and split into tertile groups based on three water arsenic concentrations: low (< 129 microg/L), medium (130-264 microg/L) and high (> 265 microg/L). Study subjects were further sub-divided into two groups ( 50 microg/L) based on the recommended upper limit of water arsenic concentration (50 microg/L) in Bangladesh. Blood samples were collected from the study subjects by venipuncture and arsenic concentrations in drinking water, hair and nail samples were measured by Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). PChE activity was assayed by spectrophotometer. RESULTS: Arsenic concentrations in hair and nails were positively correlated with the arsenic levels in drinking water. Significant decreases in PChE activity were observed with increasing concentrations of arsenic in water, hair and nails. The average levels of PChE activity in low, medium and high arsenic exposure groups were also significantly different between each group. Lower levels of PChE activity were also observed in the > 50 microg/L group compared to the

The magnitude of child injuries in Bangladesh: a major child health problem.

In recent times, many developing countries including Bangladesh not only have to cope with infectious diseases and malnutrition but also with new health problems, such as asthma, cancer and accidents. The emergence of chronic diseases and injuries has not been seen as an important health issue to date. The work presented here has the objectives of conceptualizing the dynamic changes in child mortality within the framework of the health transition, to provide a basis for projection of future mortality and disability in children in Bangladesh. This paper reviews a number of reports and published articles related to the causes of child deaths in Bangladesh. These include: 1) Year books of Bangladesh Bureau of Statistics; 2) UNICEF reports; 3) Reports of International Centre for Diarrhoeal Disease and Research, Bangladesh; and 4) Reports of Institute of Child and Mother Health. Bangladesh clearly has been progressing along its epidemiological transition. At the current stage, chronic diseases and injuries have overtaken infectious diseases as leading causes of child death. Injury has been identified as a major cause of child death in Bangladesh, and is emerging as the leading cause of child mortality, similar to what is occurring in other developing countries. For these countries, in the advancing stages of their health transition, more research aimed at understanding the dynamic change of child health priorities is urgently needed for appropriate policy and planning.