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Groundwater in northwestern parts of Bangladesh, mainly in the Chapainawabganj District, has been contaminated by arsenic. This research documents the geographical distribution of arsenic concentrations utilizing machine learning techniques. The study aims to enhance the accuracy of model predictions by precisely identifying occurrences of groundwater arsenic, enabling effective mitigation actions and yielding more beneficial results. The reductive dissolution of arsenic-rich iron oxides/hydroxides is identified as the primary mechanism responsible for the release of arsenic from sediment into groundwater. The study reveals that in the research region, alongside elevated arsenic concentrations, significant levels of sodium (Na), iron (Fe), manganese (Mn), and calcium (Ca) were present. Statistical analysis was employed for feature selection, identifying pH, electrical conductivity (EC), sulfate (SO4), nitrate (NO3), Fe, Mn, Na, K, Ca, Mg, bicarbonate (HCO3), phosphate (PO4), and As as features closely associated with arsenic mobilization. Subsequently, various machine learning models, including Naïve Bayes, Random Forest, Support Vector Machine, Decision Tree, and logistic regression, were employed. The models utilized normalized arsenic concentrations categorized as high concentration (HC) or low concentration (LC), along with physiochemical properties as features, to predict arsenic occurrences. Among all machine learning models, the logistic regression and support vector machine models demonstrated high performance based on accuracy and confusion matrix analysis. In this study, a spatial distribution prediction map was generated to identify arsenic-prone areas. The prediction map also displays that Baroghoria Union and Rajarampur region under Chapainawabganj municipality are high-risk areas and Maharajpur Union and Baliadanga Union are comparatively low-risk areas of the research area. This map will facilitate researchers and legislators in implementing mitigation strategies. Logistic regression (LR) and support vector machine (SVM) models will be utilized to monitor arsenic concentration values continuously.
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Arsênio , Monitoramento Ambiental , Água Subterrânea , Aprendizado de Máquina , Poluentes Químicos da Água , Água Subterrânea/química , Bangladesh , Arsênio/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodosRESUMO
Color fundus photographs are the most common type of image used for automatic diagnosis of retinal diseases and abnormalities. As all color photographs, these images contain information about three primary colors, i.e., red, green, and blue, in three separate color channels. This work aims to understand the impact of each channel in the automatic diagnosis of retinal diseases and abnormalities. To this end, the existing works are surveyed extensively to explore which color channel is used most commonly for automatically detecting four leading causes of blindness and one retinal abnormality along with segmenting three retinal landmarks. From this survey, it is clear that all channels together are typically used for neural network-based systems, whereas for non-neural network-based systems, the green channel is most commonly used. However, from the previous works, no conclusion can be drawn regarding the importance of the different channels. Therefore, systematic experiments are conducted to analyse this. A well-known U-shaped deep neural network (U-Net) is used to investigate which color channel is best for segmenting one retinal abnormality and three retinal landmarks.
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Blumea laciniata (Roxb.) DC. is a folk medicinal annual herb of the Asteraceae family that grows in South and Southeast Asia. In order to evaluate its phytopharmaceutical potential against diabetic, obesity, and Alzheimer's, a comprehensive phytochemical profile, in vitro and in silico enzyme inhibitory activity against α-amylase, α-glucosidase, lipase, cholinesterases, and tyrosinase along with in vitro antioxidant activity were performed. Additionally, in vivo antidiabetic activity and acute toxicity were also evaluated. The total phenolic content in various organs follows the following order: old leaf > flower bud > young leaf > flower > young stem > old stem > root, while total flavonoids followed the order: flower bud > old leaf > young leaf > flower > young stem > old stem > root. The identified phenolic compounds are 3,4-dihydroxybenzoic acid, caffeic acid, vanillic acid, p-coumaric acid, syringic acid, rosmarinic acid, trans-cinnamic acid, catechin, catechol, (-) epicatechin, rutin, quercetin, myricetin, and kaempferol, which are also expressed differently in various organs. Solvent extracts demonstrated strong antioxidant activity as well as varying levels of inhibition against the enzymes tested, with strong inhibitory activity against α-amylase, α-glucosidase, and lipase. Thirteen phenolic compounds displayed strong binding affinity in silico against studied enzymes, thus documented as bioactive. Furthermore, solvent extracts significantly suppressed blood glucose levels in mice with induced diabetes and extracts were not acutely toxic. The results suggest that Blumea laciniata (Roxb.) DC. could be a potential candidate for developing new phytopharmaceuticals and bioactive ingredients.
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Doença de Alzheimer/tratamento farmacológico , Fármacos Antiobesidade/farmacologia , Asteraceae/química , Hipoglicemiantes/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Fármacos Antiobesidade/uso terapêutico , Antioxidantes/farmacologia , Glicemia/análise , Glicemia/metabolismo , Simulação por Computador , Diabetes Mellitus Experimental/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Flavonoides/análise , Flavonoides/farmacologia , Hipoglicemiantes/uso terapêutico , Masculino , Camundongos , Simulação de Acoplamento Molecular , Fenóis/análise , Extratos Vegetais/efeitos adversos , Extratos Vegetais/uso terapêuticoRESUMO
Minichromosome maintenance protein 2 (MCM2) is a highly conserved protein from the MCM protein family that plays an important role in eukaryotic DNA replication as well as in cell cycle progression. In addition, it maintains the ploidy level consistency in eukaryotic cells, hence, mutations or alteration of this protein could result in the disintegration of the fine-tuned molecular machinery that can lead to uncontrolled cell proliferation. Moreover, MCM2 has been found to be an important marker for progression and prognosis in different cancers. Therefore, we aimed to analyze the MCM2 expression and the associated outcome in breast cancer (BC) patients based on the publicly available online databases. In this study, server-based gene expression analyses indicate the upregulation of MCM2 (p < 10-6; fold change>2.0) in various BC subtypes as compared to the respective normal tissues. Besides, the evaluation of histological sections from healthy and cancer tissues showed strong staining signals indicating higher expression of MCM2 protein. The overexpression of MCM2 was significantly correlated to promoter methylation and was related to patients' clinical features. Further, mutation analysis suggested missense as the predominant type of mutation (71.4%) with 18 copy-number alterations and 0.2% mutation frequency in the MCM2 gene. This study revealed a significant correlation (Cox p ≤ 0.05) between the higher MCM2 expression and lower patient survival. Finally, we identified the co-expressed genes with gene ontological features and signaling pathways associated in BC development. We believe that this study will provide a basis for MCM2 to be a significant biomarker for human BC prognosis.
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The development of innovative drug delivery systems, versatile to different drug characteristics with better effectiveness and safety, has always been in high demand. Chitosan, an aminopolysaccharide, derived from natural chitin biomass, has received much attention as one of the emerging pharmaceutical excipients and drug delivery entities. Chitosan and its derivatives can be used for direct compression tablets, as disintegrant for controlled release or for improving dissolution. Chitosan has been reported for use in drug delivery system to produce drugs with enhanced muco-adhesiveness, permeation, absorption and bioavailability. Due to filmogenic and ionic properties of chitosan and its derivative(s), drug release mechanism using microsphere technology in hydrogel formulation is particularly relevant to pharmaceutical product development. This review highlights the suitability and future of chitosan in drug delivery with special attention to drug loading and release from chitosan based hydrogels. Extensive studies on the favorable non-toxicity, biocompatibility, biodegradability, solubility and molecular weight variation have made this polymer an attractive candidate for developing novel drug delivery systems including various advanced therapeutic applications such as gene delivery, DNA based drugs, organ specific drug carrier, cancer drug carrier, etc.
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Quitosana/química , Sistemas de Liberação de Medicamentos , Excipientes/química , Polímeros/químicaRESUMO
Spillage of furnace oil is a more frequent event in recent times. In this study, environmental samples from furnace oil spillage sites of the Shela River, the Sundarbans, Bangladesh, were collected after three weeks of spillage. Serial dilution was applied and total seven bacterial isolates were separated as pure cultures. The oil-degrading potentiality of all seven isolates was further assessed, confirmed and compared with the growth pattern in furnace oil supplemented media, 2, 6-dichlorophenolindophenol test, and gravimetric analysis. After 7 days of incubation, isolates SS3, RW2, and SB degraded 56%, 43%, and 52% of supplemented furnace oil, respectively. The top three hydrocarbonoclastic bacterial isolates were selected as potential and identified as Pseudomonas aeruginosa (SS3), Bacillus sp. (RW2), and Serratia sp. (SB). All three isolates showed significant oil-degrading capacity compared to negative control, when incubated in sterile pond water supplemented with 2% furnace oil, suggesting them as potential bioremediation agents.
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Sulfur (S) assimilation results in the synthesis of cysteine (Cys), a common metabolite for the formation of both reduced glutathione (GSH) and ethylene. Thus, ethylene may have regulatory interaction with GSH in the alleviation of salt stress. The involvement of ethylene in the alleviation of salt stress by S application was studied in mustard (Brassica juncea cv. Pusa Jai Kisan). First, the effects of 0, 0.5, 1.0 and 2.0 mM SO4 (2) (-) were studied on photosynthetic and growth parameters to ascertain the S requirement as sufficient-S and excess-S for the plant. In further experiments, the effects of sufficient-S (1 mM SO4 (2) (-) ) and excess-S (2 mM SO4 (2) (-) ) were studied on the alleviation of salt stress-induced by 100 mM NaCl, and ethylene involvement in the alleviation of salt stress by S. Under non-saline condition, excess-S increased ethylene with less content of Cys and GSH and adversely affected photosynthesis and growth. In contrast, excess-S maximally alleviated salt stress due to high demand for S and optimal ethylene formation, which maximally increased GSH and promoted photosynthesis and growth. The involvement of ethylene in S-mediated alleviation of salt stress was further substantiated by the reversal of the effects of excess-S on photosynthesis by aminoethoxyvinylglycine (AVG), ethylene biosynthesis inhibitor. The studies suggest that plants respond differentially to the S availability under non-saline and salt stress and excess-S was more potential in the alleviation of salt stress. Further, ethylene regulates plants' response and excess S-induced alleviation of salt stress and promotion of photosynthesis.
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Etilenos/metabolismo , Mostardeira/fisiologia , Fotossíntese/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Enxofre/farmacologia , Glutationa/metabolismo , Mostardeira/efeitos dos fármacos , Mostardeira/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Salinidade , Estresse Fisiológico/efeitos dos fármacos , Sulfato Adenililtransferase/metabolismoRESUMO
The rocG gene encoding glutamate dehydrogenase from Bacillus subtilis (Bs-GluDH) was cloned, and expressed at considerable magnitude in Escherichia coli. The recombinant Bs-GluDH was purified to homogeneity and has been determined to have a hexameric structure (M(r) 270 kDa) with strict specificity for 2-oxoglutarate and L-glutamate, requiring NADH and NAD+ as cofactors respectively. The enzyme showed low thermostability with T(m) = 41 degrees C due to dissociation of the hexamer. To improve the thermostability of this enzyme, we performed error-prone PCR, introducing random mutagenesis on cloned GluDH. Two single mutant enzymes, Q144R and E27F, were isolated from the final mutant library. Their T(m) values were 61 degrees C and 49 degrees C respectively. Furthermore, Q144R had a remarkably high k(cat) value (435 s(-1)) for amination reaction at 37 degrees C, 1.3 times higher than that of the wild-type. Thus, Q144R can be used as a template gene to modify the substrate specificity of Bs-GluDH for industrial use.