ABSTRACT
Bangladesh is blessed with an extensive range of solar energy generation possibilities; however, the primary impediment to attaining its full potential in the solar energy industry is the inadequate budget in the energy sector. As a result, determining the most economical and efficient solar module configuration for each specific scenario has become a critical necessity. This study offers a comprehensive techno-economic analysis and environmental impact assessment of four distinct solar modules: monofacial, bifacial, dual-axis solar tracker, and seasonal tilt solar module, in an open area of South Sakucia Union, Bhola district, in the southwest part of Bangladesh. By integrating energy-generation capabilities, financial metrics, and environmental benefits, this research provides a holistic evaluation framework to ensure optimal economic performance and minimal adverse environmental effects for sustainable solar solutions in Bangladesh. Utilizing PV*SOL, PVsyst, and System Advisor Model (SAM) software, this study assesses energy-generation capabilities and economic viability. Despite the dual-axis solar tracker exhibiting the highest average energy generation (149,070.3 kWh/year), its higher initial cost renders it less financially viable compared to other configurations. Financial metrics reveal that the seasonal tilt configuration is the most cost-efficient, with the lowest Levelized Cost of Electricity (LCOE) at $0.0452/kWh and the highest Net Present Value (NPV) of $52,887.70. Additionally, it has the shortest Discounted Payback Period (DPBP) at 12.69 years, a favorable Internal Rate of Return (IRR) of 9.460 %, and a Profitability Index (PI) of 1.459, indicating robust returns on investment. These findings emphasize the importance of considering both energy-generation capabilities and financial metrics when evaluating solar module configurations in the southern part of Bangladesh, serving as a valuable reference for policymakers. Moreover, meticulous environmental impact assessments assist in choosing configurations with minimal adverse effects on the environment.
ABSTRACT
The uncontrolled release of harmful metal/loids from mega-scale shipbreaking activities in Bangladesh is a significant concern. This study investigated the impact of shipbreaking activities on soil and crop quality and human health in relation to metal/loid contamination. This work covered an area of 1221 km2 surrounding the shipbreaking yards in Chittagong during the wet and dry seasons between 2019 and 2020. Amongst the sixteen elements measured, the concentrations of Pb, Cd, As, V, Cr, Mn, Cu, Zn, Fe, Co, Ni, and Sn in the soil, rice, and vegetables from the four exposure sites were significantly higher compared to the control site in both seasons. Soil pollution indices indicated moderate to higher contamination levels of Pb, Zn, Cd, As, and Se in 30-50% of soil, supporting their accumulation in food crops. Source apportionment analysis identified uncontrolled shipwrecking operations as the primary anthropogenic activity mainly contributing to metal/loid pollution. Health risk analysis showed inorganic arsenic (estimated), Cd, and Pb in food crops could pose potential health threats to the general population. Spinach leaf and gourd were identified as the highest-risk contributing vegetables in the dry and wet seasons. These findings help to inform management strategies to protect agroecosystems and public health.
Subject(s)
Metals, Heavy , Soil Pollutants , Humans , Metals, Heavy/toxicity , Metals, Heavy/analysis , Soil , Environmental Monitoring , Bangladesh , Cadmium/toxicity , Cadmium/analysis , Lead/analysis , Soil Pollutants/analysis , Vegetables , Crops, Agricultural , Risk Assessment , ChinaABSTRACT
The current study was designed to evaluate the protective effect of fenugreek seed powder against As-induced neurobehavioral and biochemical perturbations using a mouse model. Mice exposed to arsenic at 10 mg/kg body weight showed development of anxiety-like behavior and memory impairment compared to control mice in elevated plus maze and Morris water maze tests, respectively. A significantly decreased acetyl and butyrylcholinesterase, superoxide dismutase and glutathione reductase activities and brain-derived neurotrophic factor levels were found in the brain of arsenic-exposed mice compared to control mice. Interestingly, supplementation of fenugreek seed powder to arsenic-treated mice significantly restored the activity of cholinesterase and antioxidant enzymes (e.g. superoxide dismutase, glutathione reductase) as well as brain-derived neurotrophic factor levels in the brain tissue of arsenic-exposed mice. Consequently, reduced anxiety-like behavior, improved learning and memory were observed in fenugreek supplemented arsenic treated mice compared to only arsenic-exposed mice group. Thus, this study suggests that fenugreek seed powder reduces arsenic-induced neurotoxicity in mice.
ABSTRACT
Ornamentals come in a variety of shapes, sizes, and colors to suit a wide range of climates, landscapes, and gardening needs. Compared to demand, a shortage of plant materials and diversity force the search for solutions for their constant acquisition and improvement to increase their commercial value, respectively. In vitro cultures are a suitable solution to meet expectations using callus culture, somatic embryogenesis, protoplast culture, and the organogenesis of protocorm-like bodies; many of these techniques are commercially practiced. Factors such as culture media, explants, carbohydrates, plant growth regulators, and light are associated with the success of in vitro propagation. Techniques, especially embryo rescue and somatic hybridization, are widely used to improve ornamentals. The development of synthetic seed allows season-independent seed production and preservation in the long term. Despite the advantages of propagation and the improvement of ornamentals, many barriers still need to be resolved. In contrast to propagation and crop developmental studies, there is also a high scope for molecular studies, especially epigenetic changes caused by plant tissue culture of ornamentals. In this review, we have accumulated and discussed an overall update on cultivation factors, propagation techniques in ornamental plant tissue culture, in vitro plant improvement techniques, and future perspectives.
ABSTRACT
Wear and corrosion are common issues of material degradation and failure in industrial appliances. Wear is a damaging process that can impact surface contacts and, more specifically, can cause the loss and distortion of material from a surface because of the contacting object's mechanical action via motion. More wear occurs during the process of corrosion, in which oxide particles or debris are released from the contacting material. These types of wear debris and accumulated oxide particles released during corrosion cause a combination of wear-corrosion processes. Bringing together the fields of tribology and corrosion research, tribocorrosion is a field of study which deals with mechanical and electrochemical interactions between bodies in motion. More specifically, it is the study of mechanisms caused by the combined effects of mechanical stress and chemical/electrochemical interactions with the environment. Tribocorrosion testing methods provide new opportunities for studying the electrochemical nature of corrosion combined with mechanical loading to establish a synergistic relationship between corrosion and wear. To improve tribological, mechanical, and anti-corrosion performances, several surface modification techniques are being applied to develop functional coatings with micro/nano features. This review of the literature explores recent and enlightening research into the tribocorrosive properties of micro/nano coatings. It also looks at recent discussions of the most common experimental methods and some newer, promising experimental methods in tribocorrosion to elucidate their applications in the field of micro/nano coatings.
Subject(s)
Oxides , Titanium , Corrosion , Motion , Stress, Mechanical , Surface Properties , Titanium/chemistryABSTRACT
Chronic exposure to arsenic via drinking water is a serious public health issue in many countries. Arsenic causes not only cancers but also non-malignant diseases, including asthma. We have previously reported that arsenic exposure increases the risk of Th2-mediated allergic asthma. The serum level of periostin, an extracellular matrix protein activated by Th2 cytokines, is recognized as a biomarker for Th2-mediated eosinophilic asthma and contributes to enhanced airway inflammation and remodeling. However, the role of periostin in arsenic-related asthma is unknown. Therefore, this study was designed to explore the associations of serum periostin levels with arsenic exposure and the features of asthma in 442 individuals in Bangladesh who participated in our previous study. Exposure levels of the participants were determined by measuring the arsenic concentrations in drinking water, hair, and nails through inductively coupled plasma mass spectroscopy. Periostin levels in serum were assessed by immunoassay. In this study, we found that serum periostin levels of the participants were increased with increasing exposure to arsenic. Notably, even the participants with 10.1-50 µg/L arsenic in drinking water had significantly higher levels of periostin than participants with <10 µg/L of water arsenic. Elevated serum periostin levels were positively associated with serum levels of Th2 mediators, such as interleukin (IL)-4, IL-5, IL-13, and eotaxin. Each log increase in periostin levels was associated with approximately eight- and three-fold increases in the odds ratios (ORs) for reversible airway obstruction (RAO) and asthma symptoms, respectively. Additionally, causal mediation analyses revealed that arsenic exposure metrics had both direct and indirect (periostin-mediated) effects on the risk of RAO and asthma symptoms. Thus, the results suggested that periostin may be involved in the arsenic-related pathogenesis of Th2-mediated asthma. The elevated serum periostin levels may predict the greater risk of asthma among the people living in arsenic-endemic areas.
Subject(s)
Arsenic Poisoning , Arsenic , Asthma , Drinking Water , Arsenic/analysis , Asthma/chemically induced , Asthma/epidemiology , Biomarkers/analysis , Drinking Water/analysis , Humans , Nails/chemistryABSTRACT
Limited information is available regarding the effects of arsenic exposure on immune function. We have recently reported that chronic exposure to As was associated asthma, as determined by spirometry and respiratory symptoms. Because T helper 2 (Th2)-driven immune responses are implicated in the pathogenesis of allergic diseases, including asthma, we studied the associations of serum Th1 and Th2 mediators with the As exposure markers and the features of asthma among individuals exposed to As. A total of 553 blood samples were selected from the same study subjects recruited in our previous asthma study. Serum levels of Th1 and Th2 cytokines were analyzed by immunoassay. Subjects' arsenic exposure levels (drinking water, hair and nail arsenic concentrations) were determined by inductively coupled plasma mass spectroscopy. Arsenic exposure levels of the subjects showed significant positive associations with serum Th2-mediators- interleukin (IL)-4, IL-5, IL-13, and eotaxin without any significant changes in Th1 mediators- interferon-γ and tumor necrosis factor-α. The ratios of Th2 to Th1 mediators were significantly increased with increasing exposure to As. Notably, most of the Th2 mediators were positively associated with serum levels of total immunoglobulin E and eotaxin. The serum levels of Th2 mediators were significantly higher in the subjects with asthma than those without asthma. The results of our study suggest that the exacerbated Th2-driven immune responses are involved in the increased susceptibility to allergic asthma among individuals chronically exposed to As.
Subject(s)
Arsenic/adverse effects , Asthma/chemically induced , Cytokines/blood , Th1 Cells/drug effects , Th1-Th2 Balance/drug effects , Th2 Cells/drug effects , Water Pollutants, Chemical/adverse effects , Adolescent , Adult , Asthma/diagnosis , Asthma/immunology , Asthma/metabolism , Bangladesh , Body Burden , Cross-Sectional Studies , Female , Humans , Immunoglobulin E/blood , Male , Middle Aged , Risk Assessment , Risk Factors , Th1 Cells/immunology , Th1 Cells/metabolism , Th2 Cells/immunology , Th2 Cells/metabolism , Young AdultABSTRACT
Histone deacetylase (HDAC) inhibitors are a class of potential therapeutics for the treatment of cancer. Bicyclic tetrapeptides equipped with methoxymethyl ketone and boronic acid as zinc-binding group were designed and synthesized. The inhibitory activities of these compounds were evaluated against HDAC enzymes. The cell-free and cell-based assay data showed that both potency and selectivity changed with the change in zinc-binding group. Boronic acid-based compound showed poor activity whereas methoxymethyl ketone-based compound displayed impressive activity in both cell-free and cell-based conditions.
Subject(s)
Boronic Acids/chemistry , Boronic Acids/pharmacology , Histone Deacetylase Inhibitors/chemistry , Histone Deacetylase Inhibitors/pharmacology , Oligopeptides/chemistry , Oligopeptides/pharmacology , Binding Sites , Cell Line , Histone Deacetylases/metabolism , Humans , Ketones/metabolism , Methylation , Zinc/metabolismABSTRACT
The naturally occurring cyclic depsipeptide, FK228 inhibits histone deacetylase (HDAC) enzymes after reductive cleavage of intra-molecular disulfide bond. One of the sulfhydryl groups produced in the reduction interacts with zinc atom that involved in the catalytic mechanism of type 1 and 2 HDACs such as HDAC1, HDAC4, and HDAC6. In the present study, we describe the development of CHAP31, trapoxin B and HC-toxin based cyclic tetrapeptides with intra-molecular disulfide bond as HDAC inhibitors. The bicyclic tetrapeptides disulfide showed potent HDAC1 and HDAC4 inhibition and p21 promoting activity.
ABSTRACT
Inhibitors of histone deacetylases (HDACs) are a promising class of anticancer agents that have an effect on gene regulation. The naturally occurring cyclic depsipeptide FK228 containing disulfide and Largazole possessing thioester functionalities act as pro-drugs and share the same HDAC inhibition mechanism in cell. Inspired from these facts, we have reported bicyclic tetrapeptide disulfide HDAC inhibitors resembling FK228 with potent activity and enhanced selectivity. In the present study, we report the design and synthesis of several mono and bicyclic tetrapeptide thioester HDAC inhibitors that share the inhibition mechanism similar to Largazole. Most of the compounds showed HDAC1 and HDAC4 inhibition and p21 promoting activity in nanomolar ranges. Among these the monocyclic peptides 1, 2 and bicyclic peptide, 4 are notable demanding more advanced research to be promising anticancer drug candidates.
Subject(s)
Antineoplastic Agents/chemical synthesis , Drug Design , Histone Deacetylase Inhibitors/chemical synthesis , Oligopeptides/chemical synthesis , Peptides, Cyclic/chemical synthesis , Prodrugs/chemical synthesis , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line , Genes, Reporter/drug effects , HEK293 Cells , Histone Deacetylase 1/antagonists & inhibitors , Histone Deacetylase 1/genetics , Histone Deacetylase 1/metabolism , Histone Deacetylase 6 , Histone Deacetylase Inhibitors/chemistry , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylases/chemistry , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/genetics , Isoenzymes/metabolism , Mice , Mink , Molecular Structure , Oligopeptides/chemistry , Oligopeptides/pharmacology , Osmolar Concentration , Peptides, Cyclic/chemistry , Peptides, Cyclic/pharmacology , Prodrugs/chemistry , Prodrugs/pharmacology , Promoter Regions, Genetic/drug effects , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Repressor Proteins/antagonists & inhibitors , Repressor Proteins/genetics , Repressor Proteins/metabolismABSTRACT
Several histone deacetylase (HDAC) inhibiting bicyclic tetrapeptides have been designed and synthesized through intramolecular ring-closing metathesis (RCM) reaction and peptide cyclization. We designed bicyclic tetrapeptides based on CHAP31, trapoxin B and HC-toxin I. The HDAC inhibitory and p21 promoter assay results showed that the aliphatic loop position as well as the hydrophobicity plays an important role toward the activity of the bicyclic tetrapeptide HDAC inhibitors.
Subject(s)
Histone Deacetylase Inhibitors/chemistry , Oligopeptides/chemistry , Peptides, Cyclic/chemistry , Histone Deacetylase Inhibitors/chemical synthesis , Histone Deacetylase Inhibitors/metabolism , Histone Deacetylases/chemistry , Histone Deacetylases/metabolism , Humans , Hydrophobic and Hydrophilic Interactions , Intercellular Signaling Peptides and Proteins , Oligopeptides/chemical synthesis , Peptides/chemistry , Peptides, Cyclic/chemical synthesis , Peptides, Cyclic/metabolism , Protein BindingABSTRACT
Two thioacetate tails were introduced to the chlamydocin- and CHAP31-related cyclic tetrapeptides. An intramolecular disulfide bridge could be formed in the CHAP31-related cyclic peptides. Both the thioacetate-tailed and disulfide-bridged peptides were potent histone deacetylase inhibitors in the presence of sulfhydryl compound. Potent p21 promoter inducing activity was also observed in vivo.
Subject(s)
Disulfides/chemistry , Histone Deacetylase Inhibitors/chemical synthesis , Peptides, Cyclic/chemical synthesis , Sulfhydryl Compounds/chemical synthesis , Chromatography, High Pressure Liquid , Histone Deacetylase Inhibitors/chemistry , Inhibitory Concentration 50 , Molecular Structure , Peptides, Cyclic/chemistry , Peptides, Cyclic/pharmacology , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/pharmacologyABSTRACT
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 (Subject(s)
Arsenic/adverse effects
, Bangladesh/epidemiology
, Cholinesterases/blood
, Adult
, Age Factors
, Arsenic/analysis
, Arsenic/blood
, Arsenic Poisoning/diagnosis
, Cholinesterases/drug effects
, Environmental Exposure/adverse effects
, Female
, Hair/chemistry
, Humans
, Male
, Nails/chemistry
, Sex Factors
, Water Pollutants, Chemical/adverse effects
, Water Pollutants, Chemical/analysis
, Water Supply/analysis
ABSTRACT
Although methane sulfonate compounds are widely used for the protein modification for their selectivity of thiol groups in proteins, their intracellular signaling events have not yet been clearly documented. This study demonstrated the methane sulfonate chemical 1,4-butanediyl-bismethanethiosulfonate (BMTS)-induced cascades of signals that ultimately led to apoptosis of Jurkat cells. BMTS induced apoptosis through fragmentation of DNA, activation of caspase-9 and caspase-3, and downregulation of Bcl-2 protein with reduction of mitochondrial membrane potential. Moreover, BMTS intensely and transiently induced intracellular reactive oxygen species (ROS) production and ROS produced by BMTS was mediated through mitochondria. We also found that a reducing agent dithiothreitol (DTT) and an anti-oxidant N-acetyl cysteine (NAC) inhibited BMTS-mediated caspase-9 and -3 activation, ROS production and induction of Annexin V/propidium iodide double positive cells, suggesting the involvement of ROS in the apoptosis process. Therefore, this study further extends our understanding on the basic mechanism of redox-linked apoptosis induced by sulfhydryl-reactive chemicals.