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This study describes how, as part of the administrative reform of Bangladesh, most of the urban local governments have set up some public service center like Pourasava Digital Center (PDC), where ICT (Information and Communication Technology) has been commonly applied to make e-services more convenient, efficient and transparent. The current study measures the Service Quality Satisfaction and Continuous Use Intention to use Pourasava Digital Center (PDC) in Bangladesh by adopting citizen participation as a moderator. Theoretically, this study has used the DeLone & McLean Information Systems (D&M IS) Success Model and Zhang's two-dimensional satisfaction model. However, most of the existing studies in Bangladesh are qualitative, and the relationship between service quality and citizen satisfaction has not been tested. A survey was conducted based on a structured questionnaire method and data collected from 332 respondents from 05 PDC and applying structural equation modelling in AMOS software while analyzing the data. The empirical results showed that the data fit the model. The finding of this study is that information quality affects specific satisfaction but not accumulative satisfaction, and specific satisfaction might not lead to accumulative satisfaction. One of the worthy findings of this study is that citizen satisfaction is highly dependent on system quality and service quality rather than information quality. The continuous use intention of the citizen is not based on specific satisfaction but significantly depends on accumulative satisfaction. To ensure the improvement of PDC's service quality, all dimensions related to the quality of service should be modified, and the administrative system and citizens should be encouraged to participate in all aspects of services.
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Participação da Comunidade , Bangladesh , Humanos , Feminino , Masculino , Inquéritos e Questionários , Adulto , Intenção , Pessoa de Meia-Idade , Satisfação Pessoal , Comportamento do ConsumidorRESUMO
The aim of this study was to investigate microplastic (MP) exposure by Nile tilapia (Oreochromis niloticus) in laboratory conditions. A total of 150 tilapia fishes were equally distributed randomly in 15 different glass tanks with five experimental conditions. Observed results depicted that the presence of MPs in different organs was mainly accumulated from the fish feed rather than externally added MPs in the culture tanks. It was also revealed that the gastrointestinal tract (GIT) was found to be the most susceptible to MPs accumulation followed by gills and muscles in order. However, muscle contained the least size of MPs followed by GITs and gills. A statistical test showed significant correlations among the average length and weight of fish with MP exposure. A filamentous shape was found to be dominant in both GITs and gills while fragment shape was dominant in muscles. FTIR results revealed a total of 12 different polymers in the fish of which two polymers (polyvinyl alcohol and ethylene vinyl acetate) were not detected in the feed-only tanks. Polypropylene (PP) and polyethylene terephthalate (PET) were found to be dominant polymers in all the experimental GIT, gills, and muscle organs. FESEM results indicated the presence of different textures including cracks, edges, flakes, scratches, grooves, and adhering particles. EDX results exhibited the presence of Na, Si, K, Ni, Cu, Zn, As, and Cd in the analyzed samples that may pose additional health risks. Thus, this study could act as baseline data for laboratory-based studies of aquaculture species in future research.
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Ciclídeos , Microplásticos , Poluentes Químicos da Água , Animais , Brânquias , PlásticosRESUMO
Objective: The fully automatic segmentation of glioma and its subregions is fundamental for computer-aided clinical diagnosis of tumors. In the segmentation process of brain magnetic resonance imaging (MRI), convolutional neural networks with small convolutional kernels can only capture local features and are ineffective at integrating global features, which narrows the receptive field and leads to insufficient segmentation accuracy. This study aims to use dilated convolution to address the problem of inadequate global feature extraction in 3D-UNet. Methods: 1) Algorithm construction: A 3D-UNet model with three pathways for more global contextual feature extraction, or 3DGE-UNet, was proposed in the paper. By using publicly available datasets from the Brain Tumor Segmentation Challenge (BraTS) of 2019 (335 patient cases), a global contextual feature extraction (GE) module was designed. This module was integrated at the first, second, and third skip connections of the 3D UNet network. The module was utilized to fully extract global features at different scales from the images. The global features thus extracted were then overlaid with the upsampled feature maps to expand the model's receptive field and achieve deep fusion of features at different scales, thereby facilitating end-to-end automatic segmentation of brain tumors. 2) Algorithm validation: The image data were sourced from the BraTs 2019 dataset, which included the preoperative MRI images of 335 patients across four modalities (T1, T1ce, T2, and FLAIR) and a tumor image with annotations made by physicians. The dataset was divided into the training, the validation, and the testing sets at an 8â¶1â¶1 ratio. Physician-labelled tumor images were used as the gold standard. Then, the algorithm's segmentation performance on the whole tumor (WT), tumor core (TC), and enhancing tumor (ET) was evaluated in the test set using the Dice coefficient (for overall effectiveness evaluation), sensitivity (detection rate of lesion areas), and 95% Hausdorff distance (segmentation accuracy of tumor boundaries). The performance was tested using both the 3D-UNet model without the GE module and the 3DGE-UNet model with the GE module to internally validate the effectiveness of the GE module setup. Additionally, the performance indicators were evaluated using the 3DGE-UNet model, ResUNet, UNet++, nnUNet, and UNETR, and the convergence of these five algorithm models was compared to externally validate the effectiveness of the 3DGE-UNet model. Results: 1) In internal validation, the enhanced 3DGE-UNet model achieved Dice mean values of 91.47%, 87.14%, and 83.35% for segmenting the WT, TC, and ET regions in the test set, respectively, producing the optimal values for comprehensive evaluation. These scores were superior to the corresponding scores of the traditional 3D-UNet model, which were 89.79%, 85.13%, and 80.90%, indicating a significant improvement in segmentation accuracy across all three regions (P<0.05). Compared with the 3D-UNet model, the 3DGE-UNet model demonstrated higher sensitivity for ET (86.46% vs. 80.77%) (P<0.05) , demonstrating better performance in the detection of all the lesion areas. When dealing with lesion areas, the 3DGE-UNet model tended to correctly identify and capture the positive areas in a more comprehensive way, thereby effectively reducing the likelihood of missed diagnoses. The 3DGE-UNet model also exhibited exceptional performance in segmenting the edges of WT, producing a mean 95% Hausdorff distance superior to that of the 3D-UNet model (8.17 mm vs. 13.61 mm, P<0.05). However, its performance for TC (8.73 mm vs. 7.47 mm) and ET (6.21 mm vs. 5.45 mm) was similar to that of the 3D-UNet model. 2) In the external validation, the other four algorithms outperformed the 3DGE-UNet model only in the mean Dice for TC (87.25%), the mean sensitivity for WT (94.59%), the mean sensitivity for TC (86.98%), and the mean 95% Hausdorff distance for ET (5.37 mm). Nonetheless, these differences were not statistically significant (P>0.05). The 3DGE-UNet model demonstrated rapid convergence during the training phase, outpacing the other external models. Conclusion: The 3DGE-UNet model can effectively extract and fuse feature information on different scales, improving the accuracy of brain tumor segmentation.
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Algoritmos , Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Imageamento Tridimensional/métodosRESUMO
Fluoroquinolone (FQ) antibiotics have become a subject of growing concern due to their increasing presence in the environment, particularly in the soil and groundwater. This review provides a comprehensive examination of the attributes, prevalence, ecotoxicity, and remediation approaches associated with FQs in environmental matrices. The paper discusses the physicochemical properties that influence the fate and transport of FQs in soil and groundwater, exploring the factors contributing to their prevalence in these environments. Furthermore, the ecotoxicological implications of FQ contamination in soil and aquatic ecosystems are reviewed, shedding light on the potential risks to environmental and human health. The latter part of the review is dedicated to an extensive analysis of remediation approaches, encompassing both in-situ and ex-situ methods employed to mitigate FQ contamination. The critical evaluation of these remediation strategies provides insights into their efficacy, limitations, and environmental implications. In this investigation, a correlation between FQ antibiotics and climate change is established, underlining its significance in addressing the Sustainable Development Goals (SDGs). The study further identifies and delineates multiple research gaps, proposing them as key areas for future investigational directions. Overall, this review aims to consolidate current knowledge on FQs in soil and groundwater, offering a valuable resource for researchers, policymakers, and practitioners engaged in environmental management and public health.
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Antibacterianos , Ecossistema , Humanos , Antibacterianos/análise , Fluoroquinolonas/análise , Ecotoxicologia , Solo/químicaRESUMO
Around half of births in Bangladesh occur at home without skilled birth personnel. This study aims to identify the geographical hot spots and cold spots of home delivery in Bangladesh and associated factors. We analyzed data from the 2017/2018 Bangladesh Demographic and Health Survey and the 2017 Bangladesh Health Facility Survey. The outcome variable was home delivery without skilled personnel supervision (yes, no). Explanatory variables included individual, household, community, and healthcare facility level factors. Moran's I was used to determine hot spots (geographic locations with notably high rates of home delivery) and cold spots (geographic areas exhibiting significantly low rates of home delivery) of home delivery. Geographically weighted regression models were used to identify cluster-specific predictors of home delivery. The prevalence of without skilled personnel supervised home delivery was 53.18%. Hot spots of non-supervised and unskilled supervised home delivery were primarily located in Dhaka, Khulna, Rajshahi, and Rangpur divisions. Cold spots of home delivery were mainly located in Mymensingh and Sylhet divisions. Predictors of higher home births in hot spot areas included women's illiteracy, lack of formal job engagement, higher number of children ever born, partner's agriculture occupation, higher community-level illiteracy, and larger distance to the nearest healthcare facility from women's homes. The study findings suggest home delivery is prevalent in Bangladesh. Awareness-building programs should emphasize the importance of skilled and supervised institutional deliveries, particularly among the poor and disadvantaged groups.
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Emerging contaminants (ECs) are becoming more prevalent in estuaries and constitute a danger to both human health and ecosystems. These pollutants can infiltrate the ecosystem and spread throughout the food chain. Because of the diversified sources and extensive human activities, estuaries are particularly susceptible to increased pollution levels. A thorough review on recent ECs (platinum group elements, pharmaceuticals and personal care products, pesticides, siloxanes, liquid crystal monomers, cationic surfactant, antibiotic resistance genes, and microplastics) in estuaries, including their incidence, detection levels, and toxic effects, was performed. The inclusion of studies from different regions highlights the global nature of this issue, with each location having its unique set of contaminants. The diverse range of contaminants detected in estuary samples worldwide underscores the intricacy of ECs. A significant drawback is the scarcity of research on the toxic mechanisms of ECs on estuarine organisms, the prospect of unidentified ECs, warrant research scopes.
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Poluentes Ambientais , Poluentes Químicos da Água , Humanos , Ecossistema , Plásticos , Estuários , Cadeia Alimentar , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodosRESUMO
Toxic metals and freshwater fish's metalloid contamination are significant environmental concerns for overall public health. However, the bioaccumulation and sources of metal(loids) in freshwater fishes from Bangladesh still remain unknown. Thus, the As, Pb, Cd, and Cr concentrations in various freshwater fish species from the Rupsha River basin were measured, including Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Mystus vittatus, Glossogobius giuris, and Pseudeutropius atherinoides. An atomic absorption spectrophotometer was used to determine metal concentrations. The mean concentrations of metal(loids) in the fish muscle (mg/kg) were found to be As (1.53) > Pb (1.25) > Cr (0.51) > Cd (0.39) in summer and As (1.72) > Pb (1.51) > Cr (0.65) > Cd (0.49) in winter. The analyzed fish species had considerably different metal(loid) concentrations with seasonal variation, and the distribution of the metals (loids) was consistent with the normal distribution. The demersal species, M. vittatus, displayed the highest bio-accumulative value over the summer. However, in both seasons, none of the species were bio-accumulative. According to multivariate statistical findings, the research area's potential sources of metal(loid) were anthropogenic activities linked to geogenic processes. Estimated daily intake, target hazard quotient (THQ), and carcinogenic risk (CR) were used to assess the influence of the risk on human health. The consumers' THQs values were < 1, indicating that there were no non-carcinogenic concerns for local consumers. Both categories of customers had CRs that fell below the permissible range of 1E - 6 to 1E - 4, meaning they were not at any increased risk of developing cancer. The children's group was more vulnerable to both carcinogenic and non-carcinogenic hazards. Therefore, the entry of metal(loids) must be regulated, and appropriate laws must be used by policymakers.
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Peixes-Gato , Metais Pesados , Poluentes Químicos da Água , Animais , Criança , Humanos , Metais Pesados/análise , Rios , Cádmio , Bioacumulação , Saúde Pública , Bangladesh , Chumbo , Peixes , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Medição de RiscoRESUMO
Owing to its geographical location, Bangladesh is highly exposed to natural disasters: the northern part is at risk of floods, while the southern part suffers from cyclones, storm surges, and salinity intrusion. This study aims to quantify the exposure to cyclones in Taltali, a southern coastal upazila of Bangladesh. To quantify the exposure, the study used 6 criteria, including elevation, slope, proximity to major water bodies, population density, proximity to cyclone tracks and land use and land cover, and produced maps focusing on each criterion. The overall exposure map was also created to observe the whole scenario of the upazila. All the analysis was done in a GIS environment using the Analytic Hierarchy Process (AHP) method. The individual criterion map represents the status of the study area in different classes. And the overall exposure map revealed that about 60 % of the study area was quantified as very highly exposed to cyclones, including 4 unions- Barabagi, Chhota Bagi, Karaibaria, Pancha Koralia and 6 Rakhain paras- Taltali, Monukhe, Momeshi, Agathakur, Saton, and Sawdagar. In numerical terms, about 8032 ha and 178 ha of land are counted as highly and moderately exposed to cyclones, respectively. Among the seven unions, the maximum area of the Barabagi and Chhota Bagi was found to be very highly exposed, followed by Panchakoralia and Karaibaria. Data from our previous study also validated the results of this study. Despite having some limitations, the study can be used to develop the capacity of the community to respond to cyclones. And the national and international communities can use the results to formulate policies regarding disaster risk reduction and risk mitigation.
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Autologous skin grafting has been commonly used in clinics for decades to close large wounds, yet the cellular and molecular interactions between the wound bed and the graft that mediates the wound repair are not fully understood. The aim of this study was to better understand the molecular changes in the wound triggered by autologous and synthetic grafting. Defining the wound changes at the molecular level during grafting sets the basis to test other engineered skin grafts by design. In this study, a full-thickness skin graft (SKH-1 hairless) mouse model was established. An autologous full-thickness skin graft (FTSG) or an acellular fully synthetic Biodegradable Temporising Matrix (BTM) was grafted. The wound bed/grafts were analysed at histological, RNA, and protein levels during the inflammation (day 1), proliferation (day 5), and remodelling (day 21) phases of wound repair. The results showed that in this mouse model, similar to others, inflammatory marker levels, including Il-6, Cxcl-1, and Cxcl-5/6, were raised within a day post-wounding. Autologous grafting reduced the expression of these inflammatory markers. This was different from the wounds grafted with synthetic dermal grafts, in which Cxcl-1 and Cxcl-5/6 remained significantly high up to 21 days post-grafting. Autologous skin grafting reduced wound contraction compared to wounds that were left to spontaneously repair. Synthetic grafts contracted significantly more than FTSG by day 21. The observed wound contraction in synthetic grafts was most likely mediated at least partly by myofibroblasts. It is possible that high TGF-ß1 levels in days 1-21 were the driving force behind myofibroblast abundance in synthetic grafts, although no evidence of TGF-ß1-mediated Connective Tissue Growth Factor (CTGF) upregulation was observed.
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Pele Artificial , Cicatrização , Camundongos , Animais , Cicatrização/fisiologia , Fator de Crescimento Transformador beta1 , Pele/lesões , Transplante de Pele/métodos , Modelos Animais de DoençasRESUMO
Fish feed is becoming an increasingly vital source of nourishment for farmed fish, which are mainly coming from marine fish and agricultural sources. Anthropogenic particles, such as microplastics, are abundant in both marine fish and agricultural byproducts that are utilized to make fish feed. This study investigated whether fish feed could be a source of microplastic contamination, and revealed that a 20 weeks adult farmed tilapia fish might consume up to 268.45 ± 1.438 microplastic particles via fish feed where finisher type feeds were found to be mostly contributory in this number. The microplastics were initially observed with a stereomicroscope and FESEM-EDS. Polymeric composition of microplastics was determined to be polypropylene (PP), nylon-6 (NY-6), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl alcohol (PVA), polyethylene (PE), high- and low-density polyethylene (HDPE, LDPE), ethylene vinyl acetate (EVA), polycarbonate (PC), poly vinyl acetate (PVAc), poly urethane (PU) and polyvinyl chloride (PVC) by FTIR. Results also revealed that the size of microplastic particles in all fish feed ranged from 14 µm to 4480 µm, with 550 ± 45.45 to 11,600 ± 56.1 microplastic particles/kg of fish feed. The FESEM-EDS data demonstrated to overlook the microplastic surface along with attachment of heavy metals onto that surface such as Pb, Ni, and Co in finisher type feed that could create additional health risks.
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Human beings are continuously bathed in radiation coming from natural and artificial sources. Although the use of radiation in medical applications is beneficial to patients, it also contributes significantly to the health hazard for radiation workers and the public if radiation-generating equipment and radioactive sources are not handled properly. 96% dose contributed from medical uses of ionizing radiation in the US population among man-made sources as per NCRP Report No. 160. There is no extensive study conducted on the large hospitals in Bangladesh following the In-Situ method. We used a real-time digital portable radiation monitor with Garmin eTrex Global Positioning System at 320 monitoring points for radiation monitoring and positioning around the ten largest hospitals in central & western Bangladesh from September to November 2021. The mean radiation dose rates around Bangabandhu Sheikh Mujib Medical University, Dhaka Medical College Hospital, Evercare Hospital, Khulna Medical College Hospital, Mitford Hospital, National Institute of Cancer Research Hospital, Popular Hospital, Rajshahi Medical College Hospital, Shaheed Suhrawardy Medical College Hospital, and Square Hospitals were measured as 0.145 ± 0.012 µSv/h, 0.135 ± 0.009 µSv/h, 0.148 ± 0.008 µSv/h, 0.139 ± 0.01 µSv/h, 0.133 ± 0.007 µSv/h, 0.153 ± 0.011 µSv/h, 0.144 ± 0.012 µSv/h, 0.137 ± 0.008 µSv/h, 0.145 ± 0.01 µSv/h, and 0.153 ± 0.009 µSv/h, respectively. The mean excess lifetime cancer risk (ELCR) of the public who lives nearby the hospital's boundary was estimated at 1.05 × 10-3, 0.983 × 10-3, 1.071 × 10-3, 1.004 × 10-3, 0.964 × 10-3, 1.084 × 10-3, 1.043 × 10-3,0.996 × 10-3, 1.051 × 10-3 & 1.112 × 10-3 respectively. ELCR in most of the locations around the ten largest hospitals in central & western Bangladesh is higher than the global average value. Radiation monitoring is significant for minimizing the public's radiation risk and keeping hospital environments as radiation-free as possible.
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Microplastic (MP) tiny fragments (< 5 mm) of conventional and specialized industrial polymers are persistent and ubiquitous in both aquatic and terrestrial ecosystem. Breathing, ingestion, consumption of food stuffs, potable water, and skin are possible routes of MP exposure that pose potential human health risk. Various microorganisms including bacteria, cyanobacteria, and microalgae rapidly colonized on MP surfaces which initiate biofilm formation. It gradually changed the MP surface chemistry and polymer properties that attract environmental metals. Physicochemical and environmental parameters like polymer type, dissolved organic matter (DOM), pH, salinity, ion concentrations, and microbial community compositions regulate metal adsorption on MP biofilm surface. A set of highly conserved proteins tightly regulates metal uptake, subcellular distribution, storage, and transport to maintain cellular homeostasis. Exposure of metal-MP biofilm can disrupt that cellular homeostasis to induce toxicities. Imbalances in metal concentrations therefore led to neuronal network dysfunction, ROS, mitochondrial damage in diseases like Alzheimer's disease (AD), Parkinson's disease (PD), and Prion disorder. This review focuses on the biofilm development on MP surfaces, factors controlling the growth of MP biofilm which triggered metal accumulation to induce neurotoxicological consequences in human body and stategies to reestablish the homeostasis. Thus, the present study gives a new approach on the health risks of heavy metals associated with MP biofilm in which biofilms trigger metal accumulation and MPs serve as a vector for those accumulated metals causing metal dysbiosis in human body.
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Bioacumulação , Biofilmes , Metais Pesados , Microplásticos , Doenças Neurodegenerativas , Humanos , Adsorção , Ecossistema , Monitoramento Ambiental , Metais Pesados/química , Metais Pesados/toxicidade , Microplásticos/química , Doenças Neurodegenerativas/induzido quimicamente , Doenças Neurodegenerativas/etiologia , Plásticos/químicaRESUMO
Parkinson's disease is a chronic neuropathy characterised by the formation of Lewy bodies (misfolded alpha-synuclein) in dopaminergic neurons of the substantia nigra and other parts of the brain. Dopaminergic neurons play a vital role in generating both motor and non-motor symptoms. Finding therapeutic targets for Parkinson's disease (PD) is hindered due to an incomplete understanding of the disease's pathophysiology. Existing evidence suggests that the gut microbiota participates in the pathogenesis of PD via immunological, neuroendocrine, and direct neural mechanisms. Gut microbial dysbiosis triggers the loss of dopaminergic neurons via mitochondrial dysfunction. Gut dysbiosis triggers bacterial overgrowth in the small intestine, which increases the permeability barrier and induces systemic inflammation. It results in excessive stimulation of the innate immune system. In addition to that, activation of enteric neurons and enteric glial cells initiates the aggregation of alpha-synuclein. This alpha-synucleinopathy thus affects all levels of the brain-gut axis, including the central, autonomic, and enteric nervous systems. Though the neurobiological signaling cascade between the gut microbiome and the central nervous system is poorly understood, gut microbial metabolites may serve as a promising therapeutic strategy for PD. This article summarises all the known possible ways of bidirectional signal communication, i.e., the "gut-brain axis," where microbes from the middle gut interact with the brain and vice versa, and highlights a unique way to treat neurodegenerative diseases by maintaining homeostasis. The tenth cranial nerve (vagus nerve) plays a significant part in this signal communication. However, the leading regulatory factor for this axis is a diet that helps with microbial colonisation and brain function. Short-chain fatty acids (SCFAs), derived from microbially fermented dietary fibres, link host nutrition to maintain intestinal homeostasis. In addition to that, probiotics modulate cognitive function and the metabolic and behavioural conditions of the body. As technology advances, new techniques will emerge to study the tie-up between gut microbes and neuronal diseases.
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This study evaluated the effects of different parts of M. paniculata (MP) extracts on convulsions and antioxidant activities in mice. Six polyphenolic compounds were identified, where epicatechin and quercetin have been identified in the highest amounts (23.01 and 32.23 mg/100 g of dry MP extract, respectively) in MP leaf and stem extracts, using Ultra Performance Liquid Chromatography. 7-day oral administration of MP at doses of 100, 200, and 400 mg/kg body weight (BW) significantly reduced convulsions and reduced mortality rates compared with seizure inducer groups. Antioxidant potentials were measured by superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS), and reduced glutathione (GSH) content in whole-brain homogenates. Gamma-aminobutyric acid (GABA) levels significantly increased in leaves and stem-treated groups, suggesting that MP leaves and stems have potent antioxidant properties that can attenuate convulsions by modulating the GABAergic system and antioxidant activities.
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Tobacco products are widely recognized as a major contributor to death. Cigarette smoke contains several toxic chemicals including heavy metals particulate causing high health risks. However, limited information has been available on the health risks associated with the heavy metals in cigarettes commonly sold in the Bangladeshi market. This study evaluated the concentrations and potential health risks posed by ten concerned heavy metals in ten widely consumed cigarette brands in Bangladesh using an atomic absorption spectrometer. The concentration (mg/kg) ranges of heavy metals Pb, Cd, Cr, As, Co, Ni, Mn, Fe, Cu, and Zn vary between 0.46-1.05, 0.55-1.03, 0.80-1.2, 0.22-0.40, 0.46-0.78, 2.59-3.03, 436.8-762.7, 115.8-184.4, 146.6-217.7, and 34.0-42.7, respectively. We assume that the heavy metals content among cigarette brands is varied due to the differences in the source of tobacco they use for cigarette preparation. The carcinogenic risks posed by heavy metals follow the order of Cr > Co > Cd > As > Ni > Pb, while the non-carcinogenic risks for Cu, Zn, Fe, and Mn were greater than unity (HQ > 1), except for Fe. The existence of toxic heavy metals in cigarette tobacco may thus introduce noticeable non-carcinogenic and carcinogenic health impacts accompanying inhalation exposure. This study provides the first comprehensive report so far on heavy metal concentration and associated health risks in branded cigarettes commonly sold in Bangladesh. Hence, this data and the information provided can serve as a baseline as well as a reference for future research and have potential implications for policy and legislation in Bangladesh.
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l-Glutamic acid/ZnS (L-GA/ZnS) composites were prepared by varying the amount of ZnS addition ranging from 1-5 wt% by means of an easy solvent casting approach. The morphological investigation, antimicrobial activity, photocatalytic enactment, and electrochemical properties of the composites were evaluated. The formation of L-GA/ZnS composites was confirmed by FTIR, UV-Vis, and photoluminescence (PL) spectroscopy. Besides, FTIR, UV-Visible, and PL data revealed the possible incorporation of ZnS into L-GA. The L-GA/ZnS composites demonstrated similar plate-like structure of L-GA with agglomerated ZnS morphology on the plate surface with diameter in the range of 50-500 nm, confirmed by FESEM/EDS measurements. The prepared composites showed excellent photocatalytic depiction towards methylene blue (MB) degradation in comparison to L-GA and ZnS. A set of supercapacitor devices were fabricated using L-GA/ZnS composites. The performance of the supercapacitor was assessed by GCD and exhibited good energy storage capacity. The prepared composites showed promising prospects for hybrid supercapacitor application. These outcomes may offer new insight into the fabrication of L-GA/ZnS composites as photocatalysts for organic contaminants treatment.
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The growing use of synthetic chemical compounds/substances in vector control of mosquitoes, associated with their adverse effects on the environment and non-target organisms, has demanded the development of eco-friendly alternatives. In this context, this study aimed to evaluate the larvicidal action of different cellulose microcrystalline (CMs) concentrations and investigate their toxicity mechanisms in Culex quinquefasciatus fourth instar larvae as a model species. Probit analysis revealed that the median lethal concentrations (LC50) for 24 h and 36 h exposure were 100 and 58.29 mg/L, respectively. We also showed that such concentrations induced a redox imbalance in the larvae, marked by an increase in the production of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS), as well as a reduction in the activity of superoxide dismutase (SOD) and catalase (CAT). Furthermore, different alterations in the external morphology of the larvae were associated with the ingestion of CMs. On the other hand, exposure of adult zebrafish (Danio rerio) to LC5024h and LC5036h for seven days did not induce any behavioral changes or alterations mutagenic, genotoxic, biochemical, or in the production of cytokines IFN-γ and IL-10. Thus, taken together, our study demonstrates for the first time that the use of CMs can constitute a promising strategy in the control of C. quinquefasciatus larvae, combining insecticidal efficiency with an "eco-friendly" approach in the fight against an important mosquito vector of several human diseases.
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Stimulus-coupled insulin secretion from the pancreatic islet ß-cells involves the fusion of insulin granules to the plasma membrane (PM) via SNARE complex formation-a cellular process key for maintaining whole-body glucose homeostasis. Less is known about the role of endogenous inhibitors of SNARE complexes in insulin secretion. We show that an insulin granule protein synaptotagmin-9 (Syt9) deletion in mice increased glucose clearance and plasma insulin levels without affecting insulin action compared to the control mice. Upon glucose stimulation, increased biphasic and static insulin secretion were observed from ex vivo islets due to Syt9 loss. Syt9 colocalizes and binds with tomosyn-1 and the PM syntaxin-1A (Stx1A); Stx1A is required for forming SNARE complexes. Syt9 knockdown reduced tomosyn-1 protein abundance via proteasomal degradation and binding of tomosyn-1 to Stx1A. Furthermore, Stx1A-SNARE complex formation was increased, implicating Syt9-tomosyn-1-Stx1A complex is inhibitory in insulin secretion. Rescuing tomosyn-1 blocked the Syt9-knockdown-mediated increases in insulin secretion. This shows that the inhibitory effects of Syt9 on insulin secretion are mediated by tomosyn-1. We report a molecular mechanism by which ß-cells modulate their secretory capacity rendering insulin granules nonfusogenic by forming the Syt9-tomosyn-1-Stx1A complex. Altogether, Syt9 loss in ß-cells decreases tomosyn-1 protein abundance, increasing the formation of Stx1A-SNARE complexes, insulin secretion, and glucose clearance. These outcomes differ from the previously published work that identified Syt9 has either a positive or no effect of Syt9 on insulin secretion. Future work using ß-cell-specific deletion of Syt9 mice is key for establishing the role of Syt9 in insulin secretion.