143 results on '"Masaaki Kurasaki"'
Search Results
2. Effects of maternal high-fat diet and green tea extract Intake on autophagy in the liver of adult rat offspring
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Yuki Ohno, Masaaki KURASAKI, and Takeshi Saito
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Nutrition and Dietetics ,Medicine (miscellaneous) - Published
- 2023
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3. Analysis of Cadmium, Epigallocatechin Gallate, and Vitamin C Co-exposure on PC12 Cellular Mechanisms
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Masaaki Kurasaki and Serene Ezra Corpus Bondad
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Programmed cell death ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Apoptosis ,Ascorbic Acid ,010501 environmental sciences ,Pharmacology ,Epigallocatechin gallate ,medicine.disease_cause ,PC12 Cells ,01 natural sciences ,Biochemistry ,Catechin ,Inorganic Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Downregulation and upregulation ,medicine ,Animals ,Cytotoxicity ,0105 earth and related environmental sciences ,0303 health sciences ,Vitamin C ,Chemistry ,030302 biochemistry & molecular biology ,Biochemistry (medical) ,food and beverages ,General Medicine ,Rats ,Oxidative Stress ,Toxicity ,Reactive Oxygen Species ,Oxidative stress ,Cadmium - Abstract
Exposure to cadmium (Cd) is a risk factor to health impairments, wherein its cytotoxicity is attributed to induction of oxidative stress. Usage of anti-oxidants, however, can help lessen the damaging effects of Cd. The effect of Cd interaction with low concentration of dietary anti-oxidants, L-ascorbic acid and (-)-epigallocatechin gallate (EGCG), to PC12 cellular mechanisms was examined. The expected toxicity of Cd was observed on PC12 cells but addition of L-ascorbic acid ameliorated this effect. On the other hand, addition of EGCG was able to increase the cytotoxicity of Cd and to decrease the protective effect of L-ascorbic acid against Cd. Increase in LDH activity and decrease in free sulfhydryl levels indicated cell membrane damage and oxidative stress, respectively, in Cd- and EGCG-Cd-treated cells. Downregulation of pro-apoptotic proteins (pro-caspase-9, p53, and ERK1) was observed in cells treated with Cd alone and EGCG-Cd, while upregulation of autophagy-linked proteins (p62 and pBeclin1) was found on L-ascorbic acid-Cd combination treatments. These findings indicate that Cd causes cells to undergo an autophagy-enhanced cell death; low-concentration EGCG and L-ascorbic acid promotes cell survival individually; however, interaction of EGCG with Cd showed enhancement of Cd toxicity and antagonism of L-ascorbic acid efficiency.
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- 2020
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4. Effects of Metals on Human Health and Ecosystem
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Md. Mostafizur Rahman, Mst. Kaniz Fatima Binte Hossain, Sadia Afrin, Takeshi Saito, and Masaaki Kurasaki
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- 2022
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5. Phytoremediation: Background, Principle, and Application, Plant Species Used for Phytoremediation
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Md. Shariful Islam, Rubaiya Akter, Md. Mostafizur Rahman, and Masaaki Kurasaki
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- 2022
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6. Polyphenol-enriched azuki bean (Vina angularis) extract reduces the oxidative stress and prevents DNA oxidation in the hearts of streptozotocin-induced early diabetic rats
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Rahel Mesfin Ketema, Masaaki Kurasaki, Yukako Ueno, Shojiro Yamasaki, Tae Kawahara, Takeshi Saito, Goh Kimura, Shin Sato, and Tomomi Kita-Tomihara
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0301 basic medicine ,030109 nutrition & dietetics ,endocrine system diseases ,Chemistry ,nutritional and metabolic diseases ,030209 endocrinology & metabolism ,DNA oxidation ,Pharmacology ,medicine.disease ,medicine.disease_cause ,Streptozotocin ,Oxidative damage ,03 medical and health sciences ,0302 clinical medicine ,Polyphenol ,Diabetes mellitus ,medicine ,sense organs ,skin and connective tissue diseases ,Oxidative stress ,Food Science ,Azuki bean ,medicine.drug - Abstract
We examined the changes in the heart of rats at the early stages of streptozotocin (STZ)-induced diabetes, and whether azuki bean extract (ABE) could influence these changes. The experimental diabe...
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- 2019
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7. Remediation of water pollution with native cyclodextrins and modified cyclodextrins: A comparative overview and perspectives
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Md. Tajuddin Sikder, Takeshi Saito, Md. Mostafizur Rahman, Toshiyuki Hosokawa, Masaaki Kurasaki, and Md. Jakariya
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Environmental remediation ,Chemistry ,General Chemical Engineering ,Heavy metals ,Nanotechnology ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,Environmental Chemistry ,0210 nano-technology - Abstract
Although native and modified cyclodextrins (CDs) are somewhat effective in environmental applications, there is a continued interest in understanding their distinct role in various applications and effectiveness. This review highlights the tremendous efforts that have been made to enhance the efficiency of CDs for challenging environmental applications such as treating multi-pollutant mixtures or elucidating sorption mechanisms. To overcome these limitations, the modification of CDs using cross-linking agents has attracted attention due to their distinctive abilities to interact with a variety of environmental pollutants. The interest in new CD derivatives has resulted in the creation of many novel materials, including cross-linked polymers or hydrogels, effective cross-linkers, CD-based composites, CD-immobilized supports, CD-based membranes, and molecularly impregnated functional materials. Some basic questions concerning the effectiveness of these CD classes still warrant clarification. In this review, we present the first comprehensive outline of environmental remediation strategies using CDs and CD derivatives to accomplish the following objectives: (i) to provide an overview of the diverse environmental applications of CD and its derivatives, (ii) to provide up-to-date and useful information about their synthesis, features, and characterization (iii) and to understand their contribution to the remediation of heavy metals and organic pollutants from a comparative point of view. Finally, modified CDs are shown to be effective, non-toxic, and degradable in comparison with native CD, especially epichlorohydrin cross-linked CD (ECP) gels, which are considered pioneers among CD derivatives.
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- 2019
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8. Adsorption mechanism of Cu(II) in water environment using chitosan-nano zero valent iron-activated carbon composite beads
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Masaaki Kurasaki, Ryo Kubota, Md. Mostafizur Rahman, Subrata Banik, Mahmuda Akter, Toshiyuki Hosokawa, Takeshi Saito, Md. Shiblur Rahaman, Md. Tajuddin Sikder, and Kaniz Fatima Binte Hossain
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Zerovalent iron ,Materials science ,chemistry.chemical_element ,Chitosan ,chemistry.chemical_compound ,Adsorption ,chemistry ,Chemical engineering ,Nano ,Water environment ,medicine ,Water treatment ,Carbon ,Activated carbon ,medicine.drug - Published
- 2019
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9. Pb (II) Remediation from Aqueous Environment Using Chitosan-Activated Carbon-Polyvinyl Alcohol Composite Beads
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Toshiyoki Hosokawa, Md. Mostafizur Rahman, Takeshi Saito, Mahmuda Akter, Noriko Hirase, Md. Tajuddin Sikder, and Masaaki Kurasaki
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Environmental Engineering ,Aqueous solution ,Environmental remediation ,Ecological Modeling ,Composite number ,Bead ,Pollution ,Polyvinyl alcohol ,chemistry.chemical_compound ,Adsorption ,chemistry ,visual_art ,visual_art.visual_art_medium ,medicine ,Environmental Chemistry ,Freundlich equation ,Water Science and Technology ,Nuclear chemistry ,Activated carbon ,medicine.drug - Abstract
Lead (Pb) is one of the greatly toxic heavy metals that can enter into the biological system through food chain and induce serious health impairments. Lead ion (Pb (II)) can be released in the environment through natural and anthropogenic sources. Among different types of remediation techniques, adsorption is one of the most well-accepted techniques due to its economic feasibility and versatility as well. Herein, the removal of Pb (II) was examined using chitosan-activated carbon-polyvinyl alcohol (CS-AC-PVA) composite beads. Results demonstrated that CS-AC-PVA composite beads have more potential to adsorb Pb (II) from the aqueous solution than lone chitosan (CS), activated carbon (AC), and chitosan-activated carbon composite beads. Moreover, CS-AC-PVA composite beads showed 44% more adsorbent capacity than CA-AC beads. The adsorption capacity of CS-AC-PVA composite beads for Pb (II) showed highest adsorption at 25 °C which is increased with increasing concentrations and decrease with increasing temperature. The equilibrium data is well described by Freundlich isotherm labeling chemical interaction via multiple adsorption sites. Thus, this hybrid CS-AC-PVA composite bead is proven as potential adsorbent for environmental remediation for Pb (II) from the aqueous solution.
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- 2021
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10. Environmental arsenic exposure and its contribution to human diseases, toxicity mechanism and management
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Md. Tajuddin Sikder, Nathan Mise, Md. Khabir Uddin, Gaku Ichihara, Md. Shiblur Rahaman, Md. Mostafizur Rahman, Masaaki Kurasaki, and Sahoko Ichihara
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Health, Toxicology and Mutagenesis ,chemistry.chemical_element ,Arsenic poisoning ,Toxicology ,Bioinformatics ,Arsenic ,Insulin resistance ,Diabetes mellitus ,Arsenic Poisoning ,medicine ,Humans ,Groundwater ,integumentary system ,Arsenic toxicity ,Mechanism (biology) ,business.industry ,General Medicine ,Environmental Exposure ,Vitamins ,medicine.disease ,Pollution ,Arsenic contamination of groundwater ,chemistry ,Toxicity ,business - Abstract
Arsenic is a well-recognized environmental contaminant that occurs naturally through geogenic processes in the aquifer. More than 200 million people around the world are potentially exposed to the elevated level of arsenic mostly from Asia and Latin America. Many adverse health effects including skin diseases (i.e., arsenicosis, hyperkeratosis, pigmentation changes), carcinogenesis, and neurological diseases have been reported due to arsenic exposure. In addition, arsenic has recently been shown to contribute to the onset of non-communicable diseases, such as diabetes mellitus and cardiovascular diseases. The mechanisms involved in arsenic-induced diabetes are pancreatic β-cell dysfunction and death, impaired insulin secretion, insulin resistance and reduced cellular glucose transport. Whereas, the most proposed mechanisms of arsenic-induced hypertension are oxidative stress, disruption of nitric oxide signaling, altered vascular response to neurotransmitters and impaired vascular muscle calcium (Ca2+) signaling, damage of renal, and interference with the renin-angiotensin system (RAS). However, the contributions of arsenic exposure to non-communicable diseases are complex and multifaceted, and little information is available about the molecular mechanisms involved in arsenic-induced non-communicable diseases and also no suitable therapeutic target identified yet. Therefore, in the future, more basic research is necessary to identify the appropriate therapeutic target for the treatment and management of arsenic-induced non-communicable diseases. Several reports demonstrated that a daily balanced diet with proper nutrient supplements (vitamins, micronutrients, natural antioxidants) has shown effective to reduce the damages caused by arsenic exposure. Arsenic detoxication through natural compounds or nutraceuticals is considered a cost-effective treatment/management and researchers should focus on these alternative options. This review paper explores the scenarios of arsenic contamination in groundwater with an emphasis on public health concerns. It also demonstrated arsenic sources, biogeochemistry, toxicity mechanisms with therapeutic targets, arsenic exposure-related human diseases, and onsets of cardiovascular diseases as well as feasible management options for arsenic toxicity.
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- 2021
11. Amelioration of Metal-Induced Cellular Stress by α-Lipoic Acid and Dihydrolipoic Acid through Antioxidative Effects in PC12 Cells and Caco-2 Cells
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Masaaki Kurasaki, Mahmuda Akter, Shojiro Yamasaki, Goh Kimura, Takeshi Saito, Tajuddin Sikder, Kaniz Fatima Binte Hossain, Tomomi Tomihara, Shiblur Rahaman, and Mostafizur Rahman
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Programmed cell death ,Antioxidant ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,lcsh:Medicine ,medicine.disease_cause ,reactive oxygen species (ROS) ,PC12 Cells ,Article ,Nrf2 ,Antioxidants ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Dihydrolipoic acid ,medicine ,Animals ,Humans ,glutathione ,Protein kinase B ,030304 developmental biology ,0303 health sciences ,Thioctic Acid ,Akt ,lcsh:R ,Public Health, Environmental and Occupational Health ,Glutathione ,Molecular biology ,Rats ,Lipoic acid ,Oxidative Stress ,chemistry ,Toxicity ,Caco-2 Cells ,cleaved PARP-1 ,030217 neurology & neurosurgery ,Oxidative stress - Abstract
α-Lipoic acid (ALA) and its reduced form dihydrolipoic acid (DHLA) are endogenous dithiol compounds with significant antioxidant properties, both of which have the potential to detoxify cells. In this study, ALA (250 μM) and DHLA (50 μM) were applied to reduce metal (As, Cd, and Pb)-induced toxicity in PC12 and Caco-2 cells as simultaneous exposure. Both significantly decreased Cd (5 μM)-, As (5 μM)-, and Pb (5 μM)-induced cell death. Subsequently, both ALA and DHLA restored cell membrane integrity and intracellular glutathione (GSH) levels, which were affected by metal-induced toxicity. In addition, DHLA protected PC12 cells from metal-induced DNA damage upon co-exposure to metals. Furthermore, ALA and DHLA upregulated the expression of survival-related proteins mTOR (mammalian target of rapamycin), Akt (protein kinase B), and Nrf2 (nuclear factor erythroid 2-related factor 2) in PC12 cells, which were previously downregulated by metal exposure. In contrast, in Caco-2 cells, upon co-exposure to metals and ALA, Nrf2 was upregulated and cleaved PARP-1 (poly (ADP-ribose) polymerase-1) was downregulated. These findings suggest that ALA and DHLA can counterbalance the toxic effects of metals. The protection of ALA or DHLA against metal toxicity may be largely due to an enhancement of antioxidant defense along with reduced glutathione level, which ultimately reduces the cellular oxidative stress.
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- 2020
12. Dietary supplementation of garlic, propolis, and wakame improves recuperation in cadmium exposed Japanese medaka fish (
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Henry Okechukwu, Ujeh and Masaaki, Kurasaki
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Gills ,Superoxide Dismutase ,Oryzias ,Catalase ,Undaria ,Animal Feed ,Glutathione ,Antioxidants ,Propolis ,Diet ,Oxidative Stress ,Liver ,Dietary Supplements ,Animals ,Lipid Peroxidation ,Garlic ,Water Pollutants, Chemical ,Cadmium - Abstract
Cadmium (Cd) toxic effects can overwhelm endogenous antioxidants and affect recuperation in fish. Thus, this study assessed antioxidative properties and ameliorating potentials of dietary supplemented garlic (D1), propolis (D2), and wakame (D3) on i) Cd bioconcentration, and ii) Cd induced toxicity during recuperation in Cd exposed Japanese medaka. In a 21-day exposure, control (0.0 mg Cd/L in water-C1) or Cd-treatment (0.3 mg Cd/L in water-T1) fish were fed medaka diets. Surviving fish in T1 were further depurated for 21-days and fed D1, D2, D3, or medaka diet (C2). Gill, liver, and muscle tissues were assessed weekly for Cd bioconcentration, metallothionein, (MT), superoxide dismutase (SOD), total glutathione (GSH), and lipid peroxidation (LPO). Results showed reduced antioxidant activity by significantly increasing tissue Cd and LPO, and significantly reducing SOD activity and GSH content in gill and muscle upon Cd exposure. In contrast, D1, D2, and D3 diets significantly reduced tissue Cd and LPO, while increasing contents of MT and GSH, and SOD activity, significantly. Other condition indices in D1, D2 and D3 groups were also significantly higher than those in C2 groups. In conclusion, dietary supplementation significantly increased recuperation and tissue functions in fish, in the order D1 D2 D3C2.
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- 2020
13. Gender Differences in Knowledge, Attitude and Preparedness to Respond to COVID-19 among Adult Population in Bangladesh: A Cross-Sectional Study
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Masaaki Kurasaki, Md. Raisul Islam, Mubashar Hasan, Khan Ah, Sahadat Hossain, Mst Sadia Sultana, and Md. Tajuddin Sikder
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Coronavirus disease 2019 (COVID-19) ,Cross-sectional study ,allergology ,Preparedness ,Environmental health ,Adult population ,Psychology - Abstract
Effective pandemic management requires understanding the level of community knowledge, attitude of people and preparedness towards COVID-19. This study aimed to assess the knowledge, attitude and preparedness toward COVID-2019 among Bangladeshi general people. A cross sectional survey was conducted from 20th March 2020 to 20th April 2020 among 1007 Bangladeshi adult people. A convenience sampling strategy was utilized and the data was collected through a self-administered questionnaire. Chi-square test was used to identify the gender differences regarding knowledge, attitude and preparedness towards COVID-19. Respondents predominately used social media to inform themselves about COVID-19 (68.10%) and female used social media more than male (p
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- 2020
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14. Green Synthesized Silver Nanoparticles-Mediated Cytotoxic Effect in Colorectal Cancer Cells: NF-κB Signal Induced Apoptosis Through Autophagy
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Takeshi Saito, Mahmuda Akter, Subrata Banik, Toshiyuki Hosokawa, A. K. M. Atique Ullah, Tajuddin Sikder, and Masaaki Kurasaki
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Silver ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Metal Nanoparticles ,Apoptosis ,010501 environmental sciences ,01 natural sciences ,Biochemistry ,Inorganic Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Autophagy ,Cytotoxic T cell ,Humans ,Viability assay ,PI3K/AKT/mTOR pathway ,0105 earth and related environmental sciences ,0303 health sciences ,030302 biochemistry & molecular biology ,Biochemistry (medical) ,NF-kappa B ,General Medicine ,Cell biology ,chemistry ,Caco-2 ,Cell culture ,Growth inhibition ,Caco-2 Cells ,Colorectal Neoplasms - Abstract
Green synthesized silver nanoparticles (Ag-NPs) have demonstrated promising effects, including cytotoxicity and anticancer potential, in different cell lines. Therefore, in our previous study, Ag-NPs were synthesized from the reduction of AgNO3 using Brassica rapa var. japonica (Bj) leaf extract as a reducing and stabilizing agent. The synthesized Ag-NPs were spherical in shape, with a size range of 15-30 nm. They had phase-centered cubic structure with strong growth inhibition potential against some bacteria. In continuation with our previous study, in the present study, we aimed to investigate the autophagy-regulated cytotoxic effect of Ag-NPs against human epithelial colorectal adenocarcinoma cells (Caco-2 cells). We found that the Bj leaf aqueous extract facilitated Brassica silver nanoparticles (Brassica Ag-NPs)-induced NF-κB mediated autophagy in Caco-2 cells. Results showed that Ag-NPs reduced cell viability of Caco-2 cells by inducing oxidative stress and DNA damage. Therefore, to understand the mechanism underlying the death-promoting activity of Ag-NPs in Caco-2 cells, western blotting was performed. Western blot analysis showed decreased expression of NFκB and increased expression of IκB, which is a sign of autophagy initiation. In addition, autophagosome formation was accelerated by the activity of p53 and light chain 3 (LC3) II. In addition, inhibition of Akt and mTOR also played a pivotal role in autophagy formation. Finally, excessive expansion of autophagy promoted apoptosis, which subsequently resulted in necrosis. These findings support a novel cell death-promoting function of autophagy by Ag-NPs in Caco-2 cells.
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- 2020
15. Curcumin alleviates arsenic-induced toxicity in PC12 cells via modulating autophagy/apoptosis
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Masaaki Kurasaki, Shiblur Rahaman, Takeshi Saito, Mahmuda Akter, Tajuddin Sikder, Subrata Banik, Mostafizur Rahman, and Toshiyuki Hosokawa
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Programmed cell death ,Curcumin ,Cell Survival ,NF-E2-Related Factor 2 ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,Caspase 3 ,Apoptosis ,02 engineering and technology ,010501 environmental sciences ,Pharmacology ,01 natural sciences ,PC12 Cells ,Antioxidants ,Arsenic ,chemistry.chemical_compound ,Autophagy ,Animals ,PI3K/AKT/mTOR pathway ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,biology ,Cytochrome c ,Public Health, Environmental and Occupational Health ,General Medicine ,Pollution ,Glutathione ,XIAP ,Rats ,chemistry ,biology.protein ,Environmental Pollutants ,Signal Transduction - Abstract
Arsenic is a recognized highly toxic contaminant, responsible for numerous human diseases and affecting many millions of people in different parts of the world. Contrarily, curcumin is a natural dietary polyphenolic compound and the main active ingredient in turmeric. Recently it has drawn great attention due to its diverse biological activities, strong antioxidant properties and therapeutic potential against many human ailments. In this study, we aimed to explore the protective effects and the regulatory role of curcumin on arsenic-induced toxicity and gain insights into biomolecular mechanism/s. Arsenic (10 μM) treatment in PC12 cells for 24 h induced cytotoxicity by decreasing cell viability and intracellular glutathione level and increasing lactate dehydrogenase activity and DNA fragmentation. In addition, arsenic caused apoptotic cell death in PC12 cells, which were confirmed from flow cytometry results. Moreover, arsenic (10 μM) treatment significantly down-regulated the inhibition factors of autophagy/apoptosis; mTOR, Akt, Nrf2, ERK1, Bcl-x, Xiap protein expressions, up-regulated the enhanced factors of autophagy/apoptosis; ULK, LC3, p53, Bax, cytochrome c, caspase 9, cleaved caspase 3 proteins and eventually caused autophagic and apoptotic cell death. However, curcumin (2.5 μM) pretreatment with arsenic (10 μM) effectively saves PC12 cells against arsenic-induced cytotoxicity through increasing cell viability, intracellular GSH level and boosting the antioxidant defense system, and limiting the LDH activity and DNA damage. Furthermore, pretreatment of curcumin with arsenic expressively alleviated arsenic-induced toxicity and cell death by reversing the expressions of proteins; mTOR, Akt, Nrf2, ERK1, Bcl-x, Xiap, ULK, LC3, p53, Bax, cytochrome c, caspase 9 and cleaved caspase 3. Our findings indicated that curcumin showed antioxidant properties through the Nrf2 antioxidant signaling pathway and alleviates arsenic-triggered toxicity in PC12 cells by regulating autophagy/apoptosis.
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- 2020
16. Phosphorylated chitin increased bone formation when implanted into rat calvaria with the Ti-device
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Qin Song, Hiroko Takita, Koichi Morimoto, Kimitoshi Yagami, Yoshinori Kuboki, Masaaki Kurasaki, Toshitake Furusawa, Rachel Sammons, Seiichi Tokura, and Shouhei Iku
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Male ,Bone Regeneration ,Ti-device ,Surface Properties ,Biomedical Engineering ,enhanced bone formation ,Calvaria ,Chitin ,macromolecular substances ,Biomaterials ,chemistry.chemical_compound ,Calcification, Physiologic ,Coated Materials, Biocompatible ,Implants, Experimental ,In vivo ,Osteogenesis ,Materials Testing ,medicine ,Animals ,Phosphorylation ,Rats, Wistar ,SIBLING proteins ,Titanium ,biology ,Skull ,General Medicine ,medicine.disease ,Phosphoproteins ,In vitro ,Rats ,carbohydrates (lipids) ,medicine.anatomical_structure ,chemistry ,Biophysics ,biology.protein ,Implant ,Calcification - Abstract
Background Previously we found that a group of phosphorylated proteins (SIBLINGs) in bone binds with the Ti-device, and increases the early bone formation around the Ti-implants remarkably. From these results, we explained the biochemical mechanism of a strong bond between living bone and Ti, which was discovered by Branemark and colleagues. For the clinical application of our findings, we need a large amount of these proteins or their substitutes. Objective We aimed to create a new molecule that equips with essential functions of SIBLINGs, Ti-binding, and bone enhancement around the Ti implant. Methods We chemically phosphorylated chitin and obtained a soluble form of phosphorylated chitin (P-chitin). In this solution, we immersed the Ti-devices of web-form (TW) which we previously developed and obtained the P-chitin coated TWs. Then we tested the P-chitin coated TWs for their calcification ability in vitro, and bone enhancing ability in vivo, by implanting them into rat calvaria. We compared the P-chitin coated TW and the non-coated TW in regard to their calcification and bone enhancing abilities. Results Ti-devices coated with phosphorylated-chitin induced a ten times higher calcification in vitro at 20 days, and four times more elevated amount of bone formation in vivo at two weeks than the uncoated Ti-device. Conclusions Phosphorylated chitin could be a partial substitute of bone SIBLING proteins and are clinically applicable to accelerate bone formation around the Ti implants, thereby achieving the strong bond between living bone and Ti.
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- 2020
17. Oxidative stress and the senescence acceleration in senescence-accelerated mouse P10 (SAMP10)
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Takeshi Saito and Masaaki Kurasaki
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Senescence ,chemistry.chemical_classification ,medicine.medical_specialty ,Antioxidant ,Chemistry ,medicine.medical_treatment ,Endogeny ,medicine.disease ,medicine.disease_cause ,Atrophy ,Endocrinology ,Limbic system ,medicine.anatomical_structure ,Enzyme ,Cerebral cortex ,Internal medicine ,medicine ,Oxidative stress - Abstract
It has been hypothesized that oxidative stress, which is an imbalance between endogenous levels of oxygen radicals and antioxidant defense systems, is the main cause of aging. Senescence-accelerated mouse prone 10 (SAMP 10), which is a strain of aging-promoting model mice, shows learning and memory impairment with age, and atrophy is observed in the cerebral cortex and limbic system. The oxygen radical production in SAM mice brain tissues increases with age. The slope of the age-dependent increase was steeper in SAMP10 than control mice. Antioxidant enzyme levels in the liver of SAMP10 were higher than those in the control mice at young age, but at old age, antioxidant enzyme levels were lower and/or similar to the levels of control mice. These results suggest that oxidative stress is strongly involved in the cause of senescence acceleration of SAMP10 and that SAMP10 is a model animal suitable for the study of normal aging.
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- 2020
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18. Contributors
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Giulia Abate, Maryam Abshirini, Verónica Alonso, Luis Álvarez-Carrión, Fawaz Alzaid, Sergio Ammendola, Shailendra Anoopkumar-Dukie, Juan A. Ardura, Sylvette Ayala-Peña, Bin Bao, Jyoti Batra, Maurizio Battino, Francielle Garghetti Battiston, Francesco Bellanti, Iris F.F. Benzie, Brunna Cristina Bremer Boaventura, Aurelio Lo Buglio, Andrew C. Bulmer, Antonio Camargo, Francieli Cembranel, Vanessa Corralo, Marco D’Agostino, Javier Delgado-Lista, Patricia Faria Di Pietro, Mathias Abiodun Emokpae, Susana Esteban, Tahereh Farkhondeh, Maria Cristina Florio, Antonio Garcia-Rios, Emiliana Giacomello, Maria Isabel Gonçalves da Silva, Arancha R. Gortázar, Francisco M. Gutierrez-Mariscal, Waseem Hassan, Mina Hemmati, Osaretin Godwin Igharo, Beata Jasiewicz, Manuel Jimenez-García, Jean Paul Kamdem, Mayuree Kanlayavattanakul, Yumi Kitahiro, Miyuki Kobara, Masaaki Kurasaki, Teresa Lino-Neto, Xiaoyan Liu, Guillermo López-Lluch, Jose Lopez-Miranda, Nattaya Lourith, Janice G. Lozada-Delgado, E.S. Mackinnon, Alessandra Magenta, Guilhermina Marques, Maryam Moossavi, David Moranta, Tetsuo Nakata, María D. Navarro-Hortal, Plácido Navas, Lucie Orliaguet, Vinood B. Patel, Francisco Perez-Jimenez, Pablo Pérez-Martinez, Ananda S. Prasad, Victor R. Preedy, Mina Yamazaki Price, José L. Quiles, Gladys Rai, Rajkumar Rajendram, A.V. Rao, L.G. Rao, Russel J. Reiter, José M. Romero-Márquez, Sergio A. Rosales-Corral, Wiramon Rungratanawanich, Clodoaldo Antônio De Sá, Takeshi Saito, Saeed Samarghandian, Eunice Santos, Fiorella Sarubbo, Rahul Saxena, Anna Scotto d’Abusco, Mahendran Sekar, Makio Shibano, Arleta Sierakowska, Sara Sileno, Gity Sotoudeh, Mariana Séfora Bezerra Sousa, Diego de Souza Buarque, Silvia Tejada, Rolf Teschke, Hiroe Toba, Luana Toniolo, Carlos A. Torres-Ramos, Daniela Uberti, Alfonso Varela-López, Gianluigi Vendemiale, Tran Dang Xuan, Elena M. Yubero-Serrano, Mehreen Zafar, and Tayebeh Zeinali
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- 2020
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19. Microbiological safety of street-vended foods in Bangladesh
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Takeshi Saito, Tajuddin Sikder, Abu Sadeque Md. Selim, Rachael A. Uson-Lopez, Masaaki Kurasaki, Morshedur Rahman, Mueena Jahan, and Md. Mostafizur Rahman
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0301 basic medicine ,medicine.medical_specialty ,business.industry ,Public health ,media_common.quotation_subject ,030106 microbiology ,Variable resistance ,Microbiological quality ,Food safety ,Coliform bacteria ,03 medical and health sciences ,Health problems ,Antibiotic resistance ,Food Animals ,Hygiene ,Environmental health ,medicine ,business ,Agronomy and Crop Science ,Food Science ,Biotechnology ,media_common - Abstract
At present, street-vended food (SVF) is becoming a serious public health concern due to the intervention of different pathogenic microorganisms. The lack of hygiene in the preparation of SVFs pose risk factors for foodborne disease outbreaks worldwide. This paper reviews the microbiological quality of SVFs between developed and developing countries to understand the similarity, gap and comparative nature of microbial promulgation. The microbial quality of 64 different types of SVFs in Bangladesh was tested and analyzed, and then compared with studies on SVFs in other countries. Most of the SVF samples from all examined places had a high microbial load (≥ 105) with identical sources and propagation characteristics. E. coli, Bacillus cereus and coliform bacteria had the highest prevalence in SVFs from Bangladesh. The presence of antibiotic-resistant microbes such as Enteriobacteriaceae and Salmonella in SVFs showed the greatest variable resistance response against a large groups of antimicrobials. Taken together, we found that the microbiological quality of SVFs and thereof the associated health problems are almost indistinguishable all over the world. Furthermore, the intervention options are very limited and are not really applied in practice. In addition, a single-focused intervention only partially succeeded. Thus, we have summarized potential options to regulate the quality of SVFs through proper hygiene practices.
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- 2018
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20. Elucidation of the mechanism of changes in the antioxidant function with the aging in the liver of the senescence-accelerated mouse P10 (SAMP10)
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Goh Kimura, Masaaki Kurasaki, Tomomi Kita, Toshiyuki Hosokawa, Tae Kawahara, Yukako Ueno, Tajuddin Sikder, Shojiro Yamasaki, Takeshi Saito, and Miki Nakanishi
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Male ,0301 basic medicine ,Senescence ,Aging ,medicine.medical_specialty ,Antioxidant ,medicine.medical_treatment ,Blotting, Western ,Mitochondrion ,Biochemistry ,Antioxidants ,Mice ,03 medical and health sciences ,Endocrinology ,Downregulation and upregulation ,Internal medicine ,Genetics ,medicine ,Animals ,Phosphorylation ,Molecular Biology ,chemistry.chemical_classification ,Glutathione Peroxidase ,biology ,Forkhead Box Protein O1 ,Superoxide Dismutase ,Chemistry ,Cell Biology ,Catalase ,Mice, Mutant Strains ,Up-Regulation ,Blot ,Disease Models, Animal ,030104 developmental biology ,Enzyme ,Liver ,biology.protein - Abstract
Senescence-accelerated mice are known to display a variety of deficits and signs of accelerated aging, but the specific mechanisms involved in this process are still unclear. In this study, we examined the expression levels of antioxidant enzymes, transcription factors responsible for the regulation of expression of these enzymes, and mitochondrial proteins in the liver of SAMP10 and SAMR1 mice at 3 and 12 months of age using western blotting analysis. To investigate the amount of oxidative damage to DNA, levels of 8-OHdG were measured in the liver of these mice. At 3 months of age, the levels of catalase, Mn-SOD, GPx, UQCRC2 and COXIV were significantly upregulated in SAMP10 mice compared with that in SAMR1 mice. However, NDUFS3 levels were not significantly different at this young age. In contrast, the expression level of catalase was significantly lower, and the levels of phosphorylated FoxO-1a and UQCRC2 were significantly higher in SAMP10 mice compared to those in SAMR1 mice; however, at 12 months of age, there were no significant differences in Mn-SOD, GPx, total -FoxO-1a, COXIV, and NDUFS3 expression between the two groups of mice. The levels of 8-OHdG in the liver were markedly higher in 12-month-old SAMP10 mice than those in 3-month-old SAMP10 and SAMR1 mice. These results suggest that an increase in number of mitochondria or a collapse in the balance between the levels of complexes I and III results in an increase in the amount of ROS and induces the expression of antioxidant enzymes in the liver of SAMP10 mice at 3 months of age. Although young SAMP10 mice produce a large amount of ROS, they also produce suitable levels of antioxidant enzymes that decompose ROS; consequently accelerated aging does not occur in young SAMP10 mice. In addition to excessive ROS production which is an important cause of aging, the level of catalase was significantly lower in SAMP10 than that in SAMR1 mice. These results suggested that overexpression of ROS and a decrease in the levels of catalase resulted in the accelerated aging observed in older SAMP10 mice. Moreover, the level of phosphorylated FoxO-1a was increased in SAMP10 compared to that in SAMR1 mice though the total amount of FoxO-1a was not significantly different between the two groups in old age. These results suggest that some impairment in the regulation mechanism of FoxO-1a phosphorylation is responsible for abnormal catalase expression and that a significant decrease in the level of catalase with aging decisively affects the metabolic balance of ROS; thus, ROS that cannot be metabolized contributes to the accelerated aging of SAMP10 mice.
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- 2018
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21. Ameliorative effects of selenium on arsenic-induced cytotoxicity in PC12 cells via modulating autophagy/apoptosis
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Masaaki Kurasaki, Takeshi Saito, Rachael A. Uson-Lopez, Md. Tajuddin Sikder, Gongxun Tan, Md. Mostafizur Rahman, and Toshiyuki Hosokawa
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inorganic chemicals ,0301 basic medicine ,Environmental Engineering ,Antioxidant ,Cell Survival ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,chemistry.chemical_element ,Apoptosis ,010501 environmental sciences ,medicine.disease_cause ,PC12 Cells ,01 natural sciences ,Arsenic ,Selenium ,03 medical and health sciences ,Autophagy ,medicine ,Animals ,Environmental Chemistry ,Drug Interactions ,PI3K/AKT/mTOR pathway ,0105 earth and related environmental sciences ,integumentary system ,Chemistry ,TOR Serine-Threonine Kinases ,Intrinsic apoptosis ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,Pollution ,Rats ,Cell biology ,Oxidative Stress ,030104 developmental biology ,Oxidative stress ,Signal Transduction - Abstract
Arsenic is well known toxicant responsible for human diseases including cancers. On the other hand, selenium is an essential trace element with significant chemopreventive effects, anticancer potentials and antioxidant properties. Although previous studies have reported antagonism/synergism between arsenic and selenium in biological systems, the biomolecular mechanism/s is still inconclusive. Therefore, to elucidate the molecular phenomena in cellular level, we hypothesized that co-exposure of selenium with arsenic may have suppressive effects on arsenic-induced cytotoxicity. We found that selenium in co-exposure with arsenic increases cell viability, and suppresses oxidative stress induced by arsenic in PC12 cells. Consequently, DNA fragmentation due to arsenic exposure was also reduced by arsenic and selenium co-exposure. Furthermore, western blot analyses revealed that simultaneous exposure of both metals significantly inhibited autophagy which further suppressed apoptosis through positively regulation of key proteins; p-mTOR, p-Akt, p-Foxo1A, p62, and expression of ubiquitin, Bax, Bcl2, NFкB, and caspases 3 and 9, although those are negatively regulated by arsenic. In addition, reverse transcriptase PCR analysis confirmed the involvement of caspase cascade in cell death process induced by arsenic and subsequent inhibition by co-exposure of selenium with arsenic. The cellular accumulation study of arsenic in presence/absence of selenium via inductively coupled plasma mass spectrometry confirmed that selenium effectively retarded the uptake of arsenic in PC12 cells. Finally, these findings imply that selenium is capable to modulate arsenic-induced intrinsic apoptosis pathway via enhancement of mTOR/Akt autophagy signaling pathway through employing antioxidant potentials and through inhibiting the cellular accumulation of arsenic in PC12 cells.
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- 2018
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22. Brassica rapa var. japonica Leaf Extract Mediated Green Synthesis of Crystalline Silver Nanoparticles and Evaluation of Their Stability, Cytotoxicity and Antibacterial Activity
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A. K. M. Atique Ullah, Mahmuda Akter, Md. Tajuddin Sikder, Takeshi Saito, Md. Mostafizur Rahman, Masaaki Kurasaki, and Toshiyuki Hosokawa
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Polymers and Plastics ,biology ,Chemistry ,Brassica ,food and beverages ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Mass spectrometry ,biology.organism_classification ,01 natural sciences ,Silver nanoparticle ,0104 chemical sciences ,Brassica rapa ,Materials Chemistry ,Viability assay ,Agar diffusion test ,0210 nano-technology ,Antibacterial activity ,Cytotoxicity ,Nuclear chemistry - Abstract
Silver nanoparticles (AgNPs) were successfully synthesized from the reduction of Ag+ using AgNO3 solution as a precursor and Brassica rapa var. japonica leaf extract as a reducing and capping agent. This study was aimed at synthesis of AgNPs, exhibiting less toxicity with high antibacterial activity. The characterization of AgNPs was carried out using UV–Vis spectrometry, energy dispersive X-ray spectrometry, fourier transform infrared spectrometry, field emission scanning electron microscopy, X-ray diffraction, atomic absorption spectrometry, and transmission electron microscopy analyses. The analyses data revealed the successful synthesis of nano-crystalline Ag possessing more stability than commercial AgNPs. The cytotoxicity of Brassica AgNPs was compared with commercial AgNPs using in vitro PC12 cell model. Commercial AgNPs reduced cell viability to 23% (control 97%) and increased lactate dehydrogenase activity at a concentration of 3 ppm, whereas, Brassica AgNPs did not show any effects on both of the cytotoxicity parameters up to a concentration level of 10 ppm in PC12 cells. Moreover, Brassica AgNPs exhibited antibacterial activity in terms of zone of inhibition against E. coli (11.1 ± 0.5 mm) and Enterobacter sp. (15 ± 0.5 mm) which was higher than some previously reported green-synthesised AgNPs. Thus, this finding can be a matter of interest for the production and safe use of green-AgNPs in consumer products.
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- 2018
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23. Spatiotemporal variations in groundwater levels and the impact on land subsidence in CanTho, Vietnam
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Masaaki Kurasaki, Huynh Vuong Thu Minh, Pankaj Kumar, Ram Avtar, Tran Van Ty, and Huynh Van Hiep
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Hydrology ,geography ,Environmental Engineering ,geography.geographical_feature_category ,Geography, Planning and Development ,Aquifer ,Context (language use) ,Subsidence ,Water resources ,Drawdown (hydrology) ,Environmental Chemistry ,Environmental science ,Saltwater intrusion ,Groundwater ,Water Science and Technology ,Water well - Abstract
This study assesses qualitative and quantitative changes in groundwater resources and their impact on land subsidence in Can Tho, Vietnam, from 2000 to 2018. Can Tho city is characterized by scarce water resources and intense industrial, domestic, agricultural, and mining usage, creating water stress. The vertical compaction rates and thus land subsidence, resulting from a head drawdown in three aquifers, were calculated using 1D consolidation of compressible porous media . Experiments were conducted in 16 wells clusters consisting of a total of 48 shallow and deep wells. The three wells from every 16 well clusters from different aquifers, namely the Middle-Upper Pleistocene confined aquifer (qp 2-3), the Upper-Pleistocence (qp3 ), and a well in Holocene (qh), respectively, were examined. The Mann Kendal test with Sen's slope was performed and for most of the wells, negative values of Kendall's tau were found, which indicated decreasing trend of groundwater level. A significant change in groundwater level were also detected during the last eighteen years from 2000 to 2018. The results show significant downward trends of groundwater level for all of the wells of aquifer qp 3 and qp2-3 except for a few shallow wells. The trend of this dropdown groundwater level for these deep wells is highly associated with extraction rates. The average subsidence rate of 4.28 cm yr−1 were observed in the study area. Tra Noc Industrial zones (QT8, QT16) showed a high subsidence rate which ranges from 5 to 7 cm yr−1 . The calculated subsidence rates indicate the ongoing groundwater overexploitation , which might place Can Tho at risk of increased flooding and saltwater intrusion in the context of climate change and sea-level rise. The findings of this study call for effective policy strategies for sustainable water resource management to limit further land subsidence.
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- 2021
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24. Melinjo (Gnetum gnemon) Seed Extract Consumption during Lactation Improved Vasodilation and Attenuated the Development of Hypertension in Female Offspring of Fructose-Fed Pregnant Rats
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Yuuka Mukai, Shin Sato, Rachael A. Uson-Lopez, Saori Kataoka, and Masaaki Kurasaki
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0301 basic medicine ,Embryology ,medicine.medical_specialty ,Offspring ,Health, Toxicology and Mutagenesis ,Vasodilation ,030204 cardiovascular system & hematology ,Biology ,Toxicology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Lactation ,medicine ,Weaning ,Adverse effect ,Fructose ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,Blood pressure ,chemistry ,Pediatrics, Perinatology and Child Health ,Gestation ,Developmental Biology - Abstract
Background Fructose intake has been correlated with increased prevalence of metabolic disorders including hypertension. In pregnant rats, fructose intake has been reported to have adverse effects on the health of its offspring. This study investigated the effects of gestational maternal fructose consumption and if supplementation with melinjo seed extracts to the maternal diet during lactation could benefit the offspring in later life. Methods Pregnant rats were randomly divided into three groups: untreated (CC), fructose-treated (FC), and fructose and melinjo-treated (FM). FC and FM groups received 100 g/L of D(-)-fructose solution by means of the drinking water during gestation while CC received normal drinking water. During lactation, CC and FC groups were given standard commercial laboratory diet, while the FM group was given commercial laboratory diet with 0.1% melinjo seed extracts. After weaning, the offspring were given normal drinking water and standard commercial diet until week 17. The blood pressure of the offspring was monitored until the 16th week. During week 17, the offspring were killed, and the kidneys were collected and analyzed. Results The level of renal phosphorylated AMP-activated protein kinase (pAMPK) in FM of 17-week female offspring was significantly higher compared with FC and CC groups. Maternal fructose intake down-regulated the renal endothelial isoform of nitric oxide synthetase expression in FC and maternal melinjo seed extract consumption maintained renal endothelial isoform of nitric oxide synthetase expression in FM of 17-week female offspring. In addition, maternal melinjo seed extract intake during lactation lowered the systolic blood pressure in FM of 17-week female offspring. Conclusion Female offspring were more vulnerable to the effects of placental fructose and melinjo seed extracts, suggesting sex-specific sensitivities. In summary, our data show that melinjo seed extract consumption during lactation improved vasodilation and attenuated the development of hypertension in the 17-week female offspring of fructose-fed pregnant rats. Birth Defects Research 110:27-34, 2018. © 2017 Wiley Periodicals, Inc.
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- 2017
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25. Spatio-Temporal Assessment of Groundwater Quality and Human Health Risk: A Case Study in Gopalganj, Bangladesh
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Masaaki Kurasaki, Shafi M. Tareq, Md. Atikul Islam, Md. Mostafizur Rahman, Md. Bodrud-Doza, Mashura Shammi, Anwar Zahid, and Md. Iftakharul Muhib
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Hydrology ,Multivariate statistics ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,010501 environmental sciences ,Seasonality ,medicine.disease ,01 natural sciences ,Pollution ,Hazard quotient ,Salinity ,Human health ,Geography ,medicine ,Groundwater quality ,Variogram ,Groundwater ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
A set of hydrochemical analysis, drinking water evaluation indices along with multivariate statistics and geostatistical model are applied to evaluate the groundwater quality of Gopalganj District, Bangladesh. A total of 46 groundwater samples are analyzed for the pre and postmonsoon seasons to assess the possible consumptive human health risk among the adults and children of the study area. It is found that most of the studied hydrochemical parameters (pH, EC, TDS, Na+, Cl−, HCO3 −, CO3 −, As, Mn, Fe, B, NO3 −, etc.) exceeded the limits stipulated by different standards for drinking water. From multivariate statistical analysis, high-salinity characteristic of groundwater resulting from seawater intrusion is observed. Spatial extensions of EC, Cl−, As, Fe, and Mn vary significantly around the study area. Strong, moderate, and weak spatial dependences are found for both seasons. The exponential semivariogram model is found to be dominant when considering the best-fit model analyzed for both seasons. In addition, mean Hazard Quotient and Hazard Index values based on As, Fe, Mn, B, NO3 −, and F− imply that the groundwater poses substantial health risk for both adults and children and fluctuates in accordance with seasonal variation. The carcinogenic risk among adults and children due to As is high in the study area during both seasons. The groundwater of the study area was characterized by high salinity possessing high level of noncarcinogenic as well as cancer-risk (As) vulnerability of the local community.
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- 2017
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26. Facile synthesis, characterization, and adsorption properties of Cd (II) from aqueous solution using β-cyclodextrin polymer impregnated in functionalized chitosan beads as a novel adsorbent
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Masaaki Kurasaki, Md. Jakariya, Sayaka Fujita, Md. Mostafizur Rahman, Md. Tajuddin Sikder, and Takeshi Saito
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Aqueous solution ,Process Chemistry and Technology ,Metal ions in aqueous solution ,Enthalpy ,Langmuir adsorption model ,Sorption ,02 engineering and technology ,010501 environmental sciences ,021001 nanoscience & nanotechnology ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,symbols.namesake ,Adsorption ,chemistry ,Chemisorption ,symbols ,Chemical Engineering (miscellaneous) ,Organic chemistry ,Epichlorohydrin ,0210 nano-technology ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Nuclear chemistry - Abstract
This study explores the adsorption capacity of carboxymethyl-β-cyclodextrin (CMβ-CD) functionalized chitosan (CS) impregnated with water-insoluble epichlorohydrin cross-linked β-cyclodextrin polymer (β-CDP) to yield CS-β-CDP-CMβ-CD composite beads for the removal of toxic Cd (II) ions from aqueous solutions. Characterization of the adsorbent was performed with XPS, FTIR, NMR, BET and SEM. The synergistic effect was expected and found at removing Cd (II) with a sorption capacity exceeding 378 mg g −1 (approximately 3.37 mmol g −1 ), which is higher than any other existing technology. The removal of Cd (II) was found maximum at pH 6.5. The rate reduction can be expressed by pseudo-second-order reaction kinetics. Thermodynamic parameters such as the enthalpy (Δ H 0 ), entropy (Δ S 0 ), and free energy change (Δ G 0 ) suggest the endothermic adsorption of Cd (II) in solution. The activation energy was calculated to be 65.62 kJ mol −1 indicating a chemisorption process. The regeneration and reusability of the adsorbent were found suitable for in situ application of this technology for Cd remediation. The Langmuir isotherm model, which is effective for analyzing equilibrium data, indicated both monolayer adsorption and chemisorption. The intraparticle diffusion model indicated both film diffusion and intraparticle diffusion as the rate limiting steps. Thus, the synthesized CS-β-CDP-CMβ-CD beads showed good adsorption selectivity for Cd (II) having excellent regeneration and reusability.
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- 2017
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27. A study of groundwater irrigation water quality in south-central Bangladesh: a geo-statistical model approach using GIS and multivariate statistics
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Md. Bodrud-Doza, Anwar Zahid, Md. Iftakharul Muhib, M. Atikul Islam, Mashura Shammi, Yeasmin Akter, Masaaki Kurasaki, and Md. Mostafizur Rahman
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Hydrology ,geography ,Irrigation ,Multivariate statistics ,geography.geographical_feature_category ,0208 environmental biotechnology ,Aquifer ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,020801 environmental engineering ,Salinity ,Geochemistry and Petrology ,Streamflow ,Sodium adsorption ratio ,Water quality ,Groundwater ,0105 earth and related environmental sciences - Abstract
Southern Bangladesh’s irrigation and drinking water is threatened by saline intrusion. This study aimed to establish an irrigation water quality index (IWQI) using a geostatistical model and multivariate indices in Gopalganj district, south-central Bangladesh. Groundwater samples were taken randomly (different depths) in two seasons (wet-monsoon and dry-monsoon). Hydrochemical analysis revealed groundwater in this area was neutral to slightly alkaline and dominating cations were Na+, Mg2+, and Ca2+ along with major anions Cl− and HCO3 −. Principal component analysis and Gibbs plot helped explain possible geochemical processes in the aquifer. The irrigation water evaluation indices showed: electrical conductivity (EC) >750 µS/cm, moderate to extreme saline; sodium adsorption ratio (SAR), excellent to doubtful; total hardness (TH), moderate to very hard; residual sodium bicarbonate, safe to marginal; Kelly’s ratio >1; soluble sodium percentage (SSP), fair to poor; magnesium adsorption ratio, harmful for soil; and IWQI, moderate to suitable. In addition, the best fitted semivariogram for IWQI, EC, SAR, SSP, and TH confirmed that most parameters had strong spatial dependence and others had moderate to weak spatial dependence. This variation might be due to the different origin/sources of major contributing ions along with the influence of variable river flow and small anthropogenic contributions. Furthermore, the spatial distribution maps for IWQI, EC, SSP, and TH during both seasons confirmed the influence of salinity from the sea; low-flow in the major river system was the driving factor of overall groundwater quality in the study area. These findings may contribute to management of irrigation and/or drinking water in regions with similar groundwater problems.
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- 2017
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28. Monitoring of heavy metal pollution and GIS derived land use changes in the major economic zone of Bangladesh
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Mahmuda Akter, Tajuddin Sikder, Sharmine Akter Simu, Subrata Banik, Farah Deeba, Krishna Prosad Mondal, Masaaki Kurasaki, Mohammad Abul Kashem, Mohammed Jamal Uddin, and Mostafizur Rahman
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Hydrology ,010504 meteorology & atmospheric sciences ,Land use ,Renewable Energy, Sustainability and the Environment ,Environmental engineering ,010501 environmental sciences ,01 natural sciences ,Soil quality ,Nutrient ,Urbanization ,Dominance (ecology) ,Environmental science ,Ecosystem ,Water pollution ,Enrichment factor ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
Water pollution and land use changes are exceeding the limit in the most important economic zone, Dhaka Export Processing Zone (DEPZ) in Bangladesh and have become a great threat to the environment. To understand this threat, the dissolved metal concentration was measured from Turag and Bangshi River near DEPZ. The land use changes of DEPZ was measured and analyzed using Bangladesh Space Research and Remote Sensing Organization (SPARRSO) and Landsat TM images through Arc GIS 10.1, ERDAS Imagine 9.1. The dissolved Pb, Cd, Ni and Zn concentration were found to be higher in compare with those of water standards except Cu at every sampling point. Elevated concentration of Cd and its corresponding enrichment factor (EF%) indicated accumulation possibility of metals in the river bed sediments. The principal component analysis result also showed the dominance of Cd ions along with Ni ions in the river water. pH was found to be the controlling factor of every dissolved metal in the rivers sourced from DEPZ. Alongside, the study represents that the land use pattern has been changed remarkably. Large volume of water has been converted into unplanned settlement and urbanization. Land use changes may lead drastic changes in the land quality, such as decreases in biodiversity, instability of ecosystem, decreased soil quality, loss of nutrients, planned and unplanned urbanization, and bare land. Comprehensive synoptic researches are required to monitor the water pollution caused by DEPZ into these rivers and to determine the exact land uses for monitoring further changes.
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- 2017
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29. Spatio-temporal assessment and trend analysis of surface water salinity in the coastal region of Bangladesh
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Masaaki Kurasaki, Md. Mostafizur Rahman, Bodrud-Doza, Anwar Zahid, Samia Quaiyum, Yeasmin Akter, Mashura Shammi, and Md. Atikul Islam
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Wet season ,Salinity ,010504 meteorology & atmospheric sciences ,Floodplain ,Coastal plain ,Health, Toxicology and Mutagenesis ,010501 environmental sciences ,01 natural sciences ,Rivers ,Dry season ,Environmental Chemistry ,Saltwater intrusion ,0105 earth and related environmental sciences ,Hydrology ,Bangladesh ,geography ,geography.geographical_feature_category ,Water ,Estuary ,General Medicine ,Pollution ,Environmental science ,Seasons ,Water quality ,Surface water ,Environmental Monitoring - Abstract
The study was designed to collect water samples over two seasons—wet-monsoon season (n = 96) (March–April) and dry-monsoon season (n = 44) (September–October)—to understand the seasonal variation in anion and cation hydrochemistry of the coastal rivers and estuaries contributing in the spatial trend in salinity. Hydrochemical examination of wet-monsoon season primarily revealed Ca–Mg–HCO3 type (66%) and followed by Na–Cl type (17.70%) water. In the dry-monsoon season, the scenario reversed with primary water being Na–Cl type (52.27%) followed by Ca–Mg–HCO3 type (31.81%). Analysis of Cl/Br molar ratio vs. Cl (mg/L) depicted sampling area affected by seawater intrusion (SWI). Spatial analysis by ordinary kriging method confirmed approximately 77% sample in the dry-monsoon, and 34% of the wet-monsoon season had shown SWI. The most saline-intruded areas in the wet-monsoon seasons were extreme south-west coastal zone of Bangladesh, lower Meghna River floodplain and Meghna estuarine floodplain and south-eastern part of Chittagong coastal plains containing the districts of Chittagong and Cox’s Bazar adjacent to Bay of Bengal. In addition, mid-south zone is also affected slightly in the dry-monsoon season. From the analyses of data, this study could further help to comprehend seasonal trends in the hydrochemistry and water quality of the coastal and estuarine rivers. In addition, it can help policy makers to obligate some important implications for the future initiatives taken for the management of land, water, fishery, agriculture and environment of coastal rivers and estuaries of Bangladesh.
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- 2017
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30. Long-term effects of maternal resveratrol intake during lactation on cholesterol metabolism in male rat offspring
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Tajuddin Sikder, Goh Kimura, Toshiyuki Hosokawa, Shin Sato, Yukako Ueno, Shojiro Yamasaki, Takeshi Saito, Tomomi Tomihara, Yuuka Mukai, Rahel Mesfin Ketema, and Masaaki Kurasaki
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0301 basic medicine ,Male ,medicine.medical_specialty ,Offspring ,030209 endocrinology & metabolism ,Resveratrol ,Reductase ,Biology ,Adult offspring ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Plasma cholesterol ,Pregnancy ,Internal medicine ,Lactation ,medicine ,Animals ,Cholesterol metabolism ,Rats, Wistar ,030109 nutrition & dietetics ,Cholesterol ,Body Weight ,Feeding Behavior ,Rats ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Liver ,Receptors, LDL ,Maternal Exposure ,lipids (amino acids, peptides, and proteins) ,Female ,Hydroxymethylglutaryl CoA Reductases ,Food Science - Abstract
Resveratrol (RSV) can protect against non-communicable diseases by improving cholesterol metabolism. However, it is unclear that effects of maternal RSV intake on health of adult offspring. In this study, we examined effects of maternal RSV intake during lactation on cholesterol metabolism in adult male rat offspring. Female Wistar rats were fed a control diet (CON) supplemented with or without RSV (20 mg/kg body weight/day) during their lactation period. Male offspring were weaned onto a standard diet and maintained on this diet for 36 weeks. As a result, plasma cholesterol level significantly decreased in RSV offspring compared to CON offspring. Furthermore, a decrease in hepatic 3-hydroxy-3-methylglutaryl-CoA reductase level and an increase in hepatic LDL-receptor level were observed in the RSV offspring. These results indicate that maternal RSV intake causes long-term decrease in plasma cholesterol level in the offspring through suppression of hepatic cholesterol biosynthesis and promotion of hepatic cholesterol uptake.
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- 2019
31. Polyphenol-enriched azuki bean (
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Tomomi, Kita-Tomihara, Shin, Sato, Shojiro, Yamasaki, Yukako, Ueno, Goh, Kimura, Rahel M, Ketema, Tae, Kawahara, Masaaki, Kurasaki, and Takeshi, Saito
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Blood Glucose ,Male ,Plant Extracts ,Vigna ,Polyphenols ,Heart ,NADH Dehydrogenase ,Catalase ,Streptozocin ,Diabetes Mellitus, Experimental ,Rats ,Electron Transport Complex III ,Oxidative Stress ,8-Hydroxy-2'-Deoxyguanosine ,Heme Oxygenase (Decyclizing) ,Animals ,Acyl-CoA Oxidase ,Phosphorylation ,Rats, Wistar ,Oxidation-Reduction ,DNA Damage ,Transcription Factors - Abstract
We examined the changes in the heart of rats at the early stages of streptozotocin (STZ)-induced diabetes, and whether azuki bean extract (ABE) could influence these changes. The experimental diabetic rats received 0 or 40 mg/kg of ABE orally for 4 weeks, whereas the control group rats received distilled water. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and expression of proteins associated with peroxisomal FA β-oxidation as well as oxidative stress markers were examined. The levels of peroxisomal ACOX1 and catalase of the diabetic groups were significantly higher than those in the control group. The levels of p62, phosphorylated-p62 (p-p62) and HO-1 in the STZ group were significantly higher than those in the control group, and the levels of p-p62, HO-1, and 8-OHdG were significantly lower by ABE administration. The STZ-induced early diabetes increases the levels of proteins related to peroxisomal FA β-oxidation and oxidative stress markers in hearts. ABE protects diabetic hearts from oxidative damage.
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- 2019
32. Protective effects of ajwain (Trachyspermum ammi L.) extract against cadmium-induced cytotoxicity and apoptosis in PC12 cells
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Masaaki Kurasaki, Subrata Banik, Takeshi Saito, Md. Mostafizur Rahman, and Md. Tajuddin Sikder
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Programmed cell death ,biology ,010405 organic chemistry ,Cytochrome c ,Glutathione ,Pharmacology ,01 natural sciences ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,chemistry ,Apoptosis ,biology.protein ,DNA fragmentation ,Viability assay ,Fragmentation (cell biology) ,Cytotoxicity - Abstract
Cadmium (Cd2+) is a heavy metal that can induce cytotoxicity leading to many chronic diseases. Ajwain (Trachyspermum ammi L.) is a popular spice with diverse pharmacological properties. It is used for the remedy of many pathological conditions that could be manifested by Cd2+ exposure e.g. inflammatory, toxic, neurological, genital or respiratory tract disorders. To reduce the Cd2+-induced cytotoxicity and apoptosis, PC12 cells were exposed/co-exposed to Cd2+ (5 or 10 μM) with/without non-toxic dose (240 μg/mL) of ethanolic extract of ajwain (AE) for 24 h. The cytotoxicity and apoptosis were evaluated by cell viability, lactate dehydrogenase (LDH) activity, glutathione levels, genomic DNA fragmentation and expressions of Bax, Bcl-2, Bcl-xL, NF-КB, cytosolic cytochrome c and caspase-3. Cd2+ reduced the cell viability significantly 24 h after exposure; however, the co-exposure of AE with Cd2+ reduced the cell death. The co-exposure also raised up glutathione levels, and decreased LDH activity. AE lessened the DNA fragmentation caused by Cd2+. AE suppressed the Cd2+-induced increased expression of apoptotic protein Bax, and promoted suppressed expressions of anti-apoptotic proteins Bcl-2, Bcl-xL and NF-КB. Moreover, it reduced the cytosolic cytochrome c levels and the caspase-3 expressions increased by Cd2+. Thus, it was suggested that AE reduced cytotoxicity and apoptosis caused by Cd2+ in PC12 cells. It inhibited Cd2+-induced apoptosis through intrinsic pathway possibly boosting up the antioxidant defense. Therefore, AE can be a candidate for a potential agent against heavy metals and/or other toxicants. Additionally, this study validated the ethno-pharmacological therapeutic uses of ajwain in various pathological conditions.
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- 2021
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33. Potential of Micranthemum umbrosum for phytofiltration of organic arsenic species from oxic water environment
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Masaaki Kurasaki, Md. Shariful Islam, and M. Tajuddin Sikder
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021110 strategic, defence & security studies ,Environmental Engineering ,Micranthemum ,Chemistry ,Aquatic ecosystem ,0211 other engineering and technologies ,chemistry.chemical_element ,Bioconcentration ,02 engineering and technology ,010501 environmental sciences ,Contamination ,01 natural sciences ,Environmental chemistry ,Botany ,Water environment ,Environmental Chemistry ,Ecotoxicology ,Metalloid ,General Agricultural and Biological Sciences ,Arsenic ,0105 earth and related environmental sciences - Abstract
Arsenic (As) is a toxic and carcinogenic metalloid that causes various hazards to human health. Phytofiltration is a more eco-friendly and green approach than chemoremediation, or other traditional technologies, for removing As from aquatic environments. Recently, Micranthemum umbrosum was shown as a promising candidate for phytofiltration of inorganic As species. This work examines the potential application of M. umbrosum to phytofiltration of organic As species, such as monomethylarsonic acid (MMAA, CH5AsO3) and dimethylarsinic acid (DMAA, C2H7AsO2), from oxic water environments. M. umbrosum plants were grown in two test concentrations of MMAA and DMAA, or a control, in a hydroponic experiment. After seven days, leaves accumulated 90 ± 3.2 and 48 ± 1.6 µg As g−1 (oven dry basis) from 1 µg As mL−1 of water added from MMAA and DMAA, respectively. Bioconcentration factor values and translocation factor values were always greater than 1.0, indicating that M. umbrosum was a good As accumulator and that leaves accumulated significantly higher amounts of As than stems and roots. Analysis of macro- and micronutrient data showed that M. umbrosum had higher resistance to organic As treatments than the control. These results confirm the potential application of M. umbrosum for phytofiltration of organic As from contaminated oxic water environments.
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- 2016
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34. Removal of Pollutants from Water by Using Single-Walled Carbon Nanotubes (SWCNTs) and Multi-walled Carbon Nanotubes (MWCNTs)
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M. Anwar Hossain, Md. Tajuddin Sikder, Mashura Shammi, Md. Khabir Uddin, Sanjida Akter Sime, Masaaki Kurasaki, and Md. Mostafizur Rahman
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Total organic carbon ,Multidisciplinary ,Materials science ,Chemical oxygen demand ,02 engineering and technology ,Carbon nanotube ,010501 environmental sciences ,021001 nanoscience & nanotechnology ,Total dissolved solids ,01 natural sciences ,law.invention ,Adsorption ,Wastewater ,law ,Environmental chemistry ,0210 nano-technology ,Water pollution ,Effluent ,0105 earth and related environmental sciences - Abstract
Water crisis is one of the supreme challenges worldwide as clean water is the ultimate need for human civilization and all other life on earth. In the present study, continuous adsorption experiments were carried out in an adsorption column to survey the efficiency of the carbon nanotubes (CNTs) for removal of pollutants from water/wastewater in terms of physicochemical parameters, such as electrical conductivity, total dissolved solids (TDS), pH, chemical oxygen demand (COD) and total organic carbon (TOC), by using both single-walled carbon nanotubes and multi-walled carbon nanotubes. Sample solutions were allowed to flow in down-flow mode through the fixed-bed of CNTs. The CNTs column showed a reduction efficiency of electrical conductivity 80 % from effluent treatment plant (ETP) treated water sample, 69.23 % from raw effluent sample, and 53.33 % from the synthetic salt water sample. Similarly, the efficiency of TDS reduction was 78.61 % from raw effluent sample, 66.86 % from ETP treated water sample, and 62.02 % from the synthetic salt water sample. COD also reduced 84.71 % from raw effluent sample and 39.58 % from the ETP treated water sample. In case of TOC, the column showed a reduction efficiency of 85.88 % from the ETP treated water sample and 70.79 % from the raw effluent sample. These findings suggested that CNTs present a great potential in removal of pollutants in terms of physicochemical parameters from water/wastewater.
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- 2016
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35. Melinjo (Gnetum gnemon) extract intake during lactation stimulates hepatic AMP-activated protein kinase in offspring of excessive fructose-fed pregnant rats
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Yuuka Mukai, Saori Kataoka, Uson Rachael Acuram, Shin Sato, Masaaki Kurasaki, Mihoko Takebayashi, and Megumi Kudo
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Male ,0301 basic medicine ,medicine.medical_specialty ,Normal diet ,Offspring ,030209 endocrinology & metabolism ,Fructose ,AMP-Activated Protein Kinases ,Biology ,03 medical and health sciences ,chemistry.chemical_compound ,Sex Factors ,0302 clinical medicine ,Endocrinology ,Acetyl Coenzyme A ,Pregnancy ,Internal medicine ,Lactation ,medicine ,Animals ,Insulin ,Phosphorylation ,Rats, Wistar ,Plant Extracts ,AMPK ,Gnetum ,medicine.disease ,Rats ,030104 developmental biology ,medicine.anatomical_structure ,Liver ,chemistry ,Blood chemistry ,Prenatal Exposure Delayed Effects ,Gestation ,Female ,Animal Science and Zoology ,Developmental Biology - Abstract
Excessive maternal fructose intake during pregnancy and in early postnatal life has metabolic consequences for the offspring. We investigated the effects of melinjo (Gnetum gnemon) extract (MeE) intake during lactation on the expression and phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) in the liver of offspring from excessive fructose-fed pregnant dams. Pregnant Wistar rats received a normal diet and 100g/L fructose solution during gestation ad libitum. At delivery, dams were divided into two groups: a control diet (FC) or a 0.1% MeE-containing diet (FM) fed during lactation. The dams that were not treated with fructose were fed a control diet (CC). At postnatal week 3, some pups were sacrificed, while the remaining continued to receive a normal diet and were sacrificed at week 17. Blood chemistry and phosphorylation levels of AMPK and acetyl-coenzyme A carboxylase (ACC) were evaluated. Plasma glucose levels in FC female offspring increased compared to that receiving CC at weeks 3 and 17; however, the levels in FM female offspring decreased at week 17. The insulin levels in FM female offspring decreased significantly compared to that in FC female offspring at week 3. Hepatic AMPK phosphorylation was upregulated in FM offspring at week 3 and in female, but not male, offspring at week 17. ACC phosphorylation in FM female offspring was upregulated at week 17. Our results suggest that maternal MeE intake during lactation may modulate the hepatic AMPK pathways in female offspring.
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- 2016
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36. Adsorption kinetic model of alginate gel beads synthesized micro particle-prussian blue to remove cesium ions from water
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Shinji Itoh, Md. Tajuddin Sikder, Takahiro Sasaki, Shunitz Tanaka, Masaaki Kurasaki, Yoshihiro Mihara, and Hideaki Yamagishi
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Langmuir ,Prussian blue ,Process Chemistry and Technology ,Sodium ,Potassium ,Kinetics ,Inorganic chemistry ,chemistry.chemical_element ,02 engineering and technology ,010501 environmental sciences ,021001 nanoscience & nanotechnology ,01 natural sciences ,Ion ,chemistry.chemical_compound ,Adsorption ,chemistry ,Caesium ,0210 nano-technology ,Safety, Risk, Reliability and Quality ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Biotechnology - Abstract
Prussian blue (PB) impregnated in alginate gel (AG) beads were synthesized in order to test their viability for removing cesium (Cs) ions from wastewater. The impregnation yields PB-AG(syn.) beads containing very fine crystals of PB incorporated into the AG beads. The interaction between PB-AG(syn.) beads and Cs ions was investigated by adsorption experiments and analyzed using Langmuir and adsorption-kinetic models. The adsorption of Cs ions onto PB-AG(syn.) beads reached equilibrium after 12 h. The maximum adsorption capacities of the PB-AG(syn.) beads were 0.557 mg bead −1 and the kinetic rate was found to be k 1 = 1.72 × 10 −1 min −1 at pH 6.0 for the pseudo first order, and 4.65 × 10 −1 bead −1 mg −1 min −1 at pH 6.0 for the pseudo second order. The effects of pH, organic acids and salts such as potassium and sodium ions onto the adsorption of Cs ions by PB-AG(syn.) beads were found insignificant and low. Consequently, the PB-AG(syn.) beads showed a high capacity for the removal of Cs ions from water.
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- 2016
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37. Assessment of the Status of Groundwater Arsenic at Singair Upazila, Manikganj Bangladesh; Exploring the Correlation with Other Metals and Ions
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Masaaki Kurasaki, M. Khabir Uddin, Mashura Shammi, Md. Mostafizur Rahman, Joti Bikash, Tanveer Ahmed, Masahiro Maruo, and Rebeka Sultana
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geography ,geography.geographical_feature_category ,Chemistry ,Magnesium ,Health, Toxicology and Mutagenesis ,Potassium ,0207 environmental engineering ,Public Health, Environmental and Occupational Health ,chemistry.chemical_element ,Aquifer ,02 engineering and technology ,Manganese ,010501 environmental sciences ,Phosphate ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,Nitrate ,Environmental chemistry ,020701 environmental engineering ,Groundwater ,Arsenic ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
Comparative study was conducted to correlate arsenic (As), iron (Fe), copper (Cu), manganese (Mn), calcium (Ca2+), magnesium (Mg2+), potassium (K+), nitrate (NO3 −), phosphate (PO4 3−), and ammonia (NH3) by determining their concentration at different depths of the tube-wells in the selected study area at Singair, Manikganj Bangladesh. Total 99 tube-well water samples were collected from the study area. In most of the sampling points, the present concentrations of As were less than the previous concentrations. The correlation between As and Fe was positively significant. It can be suggested possible adsorption/co-precipitation of As with Fe in shallow aquifer. However, the relationship between As and Mn was not significantly observed. On the other hand, relationship between Cu and As showed a positive significant correlation. The correlation between As and PO4 3− was also significant, although the correlation between As and NO3 − was not significant. PO4 3− may come from phosphate fertilizers application and can be a contributor of As in the shallow aquifer. The PCA biplot also indicated the significant relationship between As, Cu, Fe and PO4 3−. Excessive withdrawal of tube-well water along with aquifer dynamics and ionic interference might be responsible for the mobilization of As in the study area.
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- 2016
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38. Amelioration of butylated hydroxytoluene against inorganic mercury induced cytotoxicity and mitochondrial apoptosis in PC12 cells via antioxidant effects
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Takeshi Saito, Kaniz Fatima Binte Hossain, Masaaki Kurasaki, and Toshiyuki Hosokawa
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Antioxidant ,Cell Survival ,medicine.medical_treatment ,Heme oxygenege 1 ,DNA fragmentation ,Apoptosis ,Pharmacology ,Toxicology ,medicine.disease_cause ,PC12 Cells ,Nrf2 ,ERK1 ,Antioxidants ,03 medical and health sciences ,chemistry.chemical_compound ,0404 agricultural biotechnology ,medicine ,Animals ,Butylated hydroxytoluene ,PI3K/AKT/mTOR pathway ,030304 developmental biology ,0303 health sciences ,biology ,Cytochrome c ,Intrinsic apoptosis ,04 agricultural and veterinary sciences ,General Medicine ,Glutathione ,Butylated Hydroxytoluene ,040401 food science ,Mitochondria ,Rats ,chemistry ,Oxidative stress ,biology.protein ,Food Science - Abstract
Mercury (Hg) is a toxic metal, well-known for its dangerous health effects on human. Butylated hydroxytoluene (BHT) is a phenolic component generally consumed as a food additive as an antioxidant. However, BHT induced antioxidant properties against heavy metals-influenced toxicity are little studied. We hypothesized that BHT has a regulatory effect on Hg-induced cytotoxicity. The objective of this research was to assess the protecting effects of BHT against inorganic Hg (iHg)-toxicity in PC12 cells, where cells were treated with/without HgCl2 (Hg2+) (5 μM) and BHT (100 μM) for 48 h and analyzed further. Cells treated by Hg caused a significant cell viability reduction, membrane damage, glutathione reduction, DNA fragmentation, ROS generation, with suppressed expressions of akt, mTOR, ERK1, Nrf2 and HO1; and elevated apoptotic expressions of p53, Bax, cytochrome c and active caspase 3. However, BHT and Hg2+ co-exposure showed prevention against Hg2+-toxicity by improving GSH content and inhibiting ROS generation and oxidative stress mediated damages. Additionally, BHT co-treatment inverted the pro-apoptotic proteins by augmenting pro-survival regulatory proteins akt, mTOR, ERK1, Nrf2 and HO1. These findings proved that BHT inhibits Hg2+-toxicity, hindering ROS generation and intrinsic apoptosis, via enhancing glutathione and antioxidants; and suggested BHT implications as therapeutic.
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- 2020
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39. Regulatory effects of dihydrolipoic acid against inorganic mercury-mediated cytotoxicity and intrinsic apoptosis in PC12 cells
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Mostafizur Rahman, Tajuddin Sikder, Kaniz Fatima Binte Hossain, Takeshi Saito, Toshiyuki Hosokawa, and Masaaki Kurasaki
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Programmed cell death ,Cell Survival ,Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,Apoptosis ,Caspase 3 ,02 engineering and technology ,010501 environmental sciences ,PC12 Cells ,01 natural sciences ,Antioxidants ,chemistry.chemical_compound ,Dihydrolipoic acid ,Animals ,Cytotoxicity ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Thioctic Acid ,biology ,Cytochrome c ,Intrinsic apoptosis ,Public Health, Environmental and Occupational Health ,Mercury ,General Medicine ,Glutathione ,Pollution ,Molecular biology ,Rats ,Lipoic acid ,chemistry ,biology.protein ,Environmental Pollutants ,DNA Damage ,Signal Transduction - Abstract
Mercury (Hg) is an extremely dangerous environmental contaminant, responsible for human diseases including neurological disorders. However, the mechanisms of inorganic Hg (iHg)-induced cell death and toxicity are little known. Dihydrolipoic acid (DHLA) is the reduced form of a naturally occurring compound lipoic acid, which act as a potent antioxidant through multiple mechanisms. So we hypothesized that DHLA has an inhibitory role on iHg-cytotoxicity. The purposes of this research were to investigate mechanism/s of cytotoxicity of iHg, as well as, the cyto-protection of DHLA against iHg induced toxicity using PC12 cells. Treatment of PC12 cells with HgCl2 (Hg2+) (0–2.5 μM) for 48 h resulted in significant toxic effects, such as, cell viability loss, high level of lactate dehydrogenase (LDH) release, DNA damage, cellular glutathione (GSH) level decrease and increased Hg accumulation. In addition, protein level expressions of akt, p-akt, mTOR, GR, NFkB, ERK1, Nrf2 and HO-1 in cells were downregulated; and cleaved caspase 3 and cytochrome c release were upregulated after Hg2+ (2.5 μM) exposure and thus inducing apoptosis. Hg2+induced apoptosis was also confirmed by flow cytometry. However, pretreatment with DHLA (50 μM) for 3 h before Hg2+ (2.5 μM) exposure showed inhibition against iHg2+-induced cytotoxicity by reversing cell viability loss, LDH release, DNA damage, GSH decrease and inhibiting Hg accumulation. Moreover, DHLA pretreatment reversed the protein level expressions of akt, p-akt, mTOR, GR, NFkB, ERK1, Nrf2, HO-1, cleaved caspase 3 and cytochrome c. In conclusion, results showed that DHLA could attenuate Hg2+-induced cytotoxicity via limiting Hg accumulation, boosting up of antioxidant defense, and inhibition of apoptosis in cells.
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- 2020
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40. Investigating the protective actions of D-pinitol against arsenic-induced toxicity in PC12 cells and the underlying mechanism
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Masaaki Kurasaki, Md. Tajuddin Sikder, Takeshi Saito, Md. Shiblur Rahaman, Md. Mostafizur Rahman, Mahmuda Akter, and Toshiyuki Hosokawa
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Antioxidant ,Cell Survival ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,Glutathione reductase ,chemistry.chemical_element ,010501 environmental sciences ,Pharmacology ,Protective Agents ,Toxicology ,PC12 Cells ,01 natural sciences ,Arsenic ,03 medical and health sciences ,chemistry.chemical_compound ,Autophagy ,medicine ,Animals ,Humans ,Viability assay ,Cytotoxicity ,PI3K/AKT/mTOR pathway ,030304 developmental biology ,0105 earth and related environmental sciences ,0303 health sciences ,General Medicine ,Glutathione ,Rats ,chemistry ,Apoptosis ,Inositol - Abstract
Arsenic is awfully toxic metalloid responsible for many human diseases all over the world. Contrastingly, D-pinitol is a naturally occurring bioactive dietary compound has antioxidant properties. The objective of this study is to elucidate the protective actions of D-pinitol on arsenic-induced cytotoxicity and explore its controlling role in biomolecular mechanisms in PC12 cells. Obtained results demonstrated that co-exposure of D-pinitol with arsenic increases cell viability, decreases DNA damage and protects PC12 cells from arsenic-induced cytotoxicity by increasing glutathione (GSH) level and glutathione reductase (GR). Protein expression of western blot analysis showed that co-exposure of D-pinitol and arsenic significantly inhibited arsenic-induced autophagy which further suppressed apoptosis through up-regulation of survival factors; mTOR, p-mTOR, Akt, p-Akt, NF-кB, Nrf2, ERK1, GR, Bcl-x and down-regulation of death factors; p53, Bax, cytochrome c, LC3, although arsenic regulated those factors negatively. These results of this study suggested that D-pinitol protects PC12 cells from arsenic-induced cytotoxicity.
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- 2020
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41. Selenium and zinc protections against metal-(loids)-induced toxicity and disease manifestations: A review
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Shiblur Rahaman, Tajuddin Sikder, Kaniz Fatima Binte Hossain, Subrata Banik, Mahmuda Akter, Toshiyuki Hosokawa, Takeshi Saito, Md. Mostafizur Rahman, Serene Ezra Corpus Bondad, and Masaaki Kurasaki
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Health, Toxicology and Mutagenesis ,0211 other engineering and technologies ,chemistry.chemical_element ,Metal toxicity ,02 engineering and technology ,Zinc ,010501 environmental sciences ,Protective Agents ,01 natural sciences ,Arsenic ,Metal ,Selenium ,Metals, Heavy ,Animals ,Humans ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Cadmium ,Chemistry ,Public Health, Environmental and Occupational Health ,General Medicine ,Environmental Exposure ,Mercury ,Pollution ,Trace Elements ,Lead ,Environmental chemistry ,visual_art ,Toxicity ,Models, Animal ,visual_art.visual_art_medium ,Metalloid ,Public Health - Abstract
Metals are ubiquitous in the environment due to huge industrial applications in the form of different chemicals and from extensive mining activities. The frequent exposures to metals and metalloids are crucial for the human health. Trace metals are beneficial for health whereas non-essential metals are dangerous for the health and some are proven etiological factors for diseases including cancers and neurological disorders. The interactions of essential trace metals such as selenium (Se) and zinc (Zn) with non-essential metals viz. lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in biological system are very critical and complex. A huge number of studies report the protective role of Se and Zn against metal toxicity, both in animal and cellular levels, and also explain the numerous mechanisms involved. However, it has been considered that a tiny dyshomeostasis in the metals/trace metals status in biological system could induce severe deleterious effects that can manifest to numerous diseases. Thus, in this particular review, we have demonstrated the critical protection mechanism/s of Se and Zn against Cd, Pb, As and Hg toxicity in a one by one manner to clarify the up-to-date findings and perspectives. Furthermore, biomolecular consequences are comprehensively presented in light of particular cellular/biomolecular events which are somehow linked to a subsequent disease. The analyzed reports support significant protection potential of Se and Zn, either alone or in combination with other agents, against each of the abovementioned non-essential metals. However, Se and Zn are still not being used as detoxifying agents due to some unexplained reasons. We hypothesized that Se could be a potential candidate for detoxifying As and Hg regardless of their chemical speciations, but requires intensive clinical trials. However, particularly Zn-Hg interaction warrants more investigations both in animal and cellular level.
- Published
- 2018
42. Azuki bean (Vigna angularis ) extract stimulates the phosphorylation of AMP-activated protein kinase in HepG2 cells and diabetic rat liver
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Shin Sato, Yuuka Mukai, Saori Kataoka, and Masaaki Kurasaki
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0301 basic medicine ,medicine.medical_specialty ,Nutrition and Dietetics ,biology ,Chemistry ,Kinase ,Liver cell ,AMPK ,03 medical and health sciences ,030104 developmental biology ,Endocrinology ,AMP-activated protein kinase ,Downregulation and upregulation ,Internal medicine ,biology.protein ,medicine ,Phosphorylation ,Protein kinase A ,Agronomy and Crop Science ,Protein kinase B ,Food Science ,Biotechnology - Abstract
BACKGROUND The activation of AMP-activated protein kinase (AMPK) has a beneficial effect on hyperglycaemia. The aim of this study was to examine whether an azuki bean (Vigna angularis) extract (ABE) stimulates the AMPK or insulin signalling pathways in a liver cell line in response to hyperglycaemia, as well as in a diabetic rat liver. RESULTS HepG2 cells were incubated with 5 or 20 mmol L−1 glucose and then treated with ABE. Streptozotocin-induced diabetic rats received 0, 10, or 40 mg kg−1 ABE orally. Blood chemistry and phosphorylation of AMPK and Akt (a serine/threonine kinase) in the livers were examined. There was a significant increase in the levels of AMPK and Akt phosphorylation in ABE-treated HepG2 cells. AMPK phosphorylation increased significantly in glucose-stimulated HepG2 cells that were treated with ABE. In the 40 mg kg−1 ABE-treated diabetic rats, the glucose levels were lower than in the control. Phosphorylation of AMPK in ABE-untreated diabetic rat livers decreased significantly. Conversely, ABE treatment increased the phosphorylation of AMPK and Akt in the diabetic rat liver. CONCLUSION ABE treatment upregulated AMPK phosphorylation in HepG2 cells, and upregulated AMPK and Akt phosphorylation in the diabetic rat liver. These data suggest that ABE can potentially improve glucose intolerance. © 2015 Society of Chemical Industry
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- 2015
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43. Alteration of Water Pollution Level with the Seasonal Changes in Mean Daily Discharge in Three Main Rivers around Dhaka City, Bangladesh
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Masaaki Kurasaki, Mashura Shammi, Md. Saiful Islam, Abdul Kadir Ibne Kamal, Shafi M. Tareq, Takeshi Saito, M. Khabir Uddin, Shunitz Tanaka, Hideki Kuramitz, and Tomohiro Sugano
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Biochemical oxygen demand ,Hydrology ,Pollution ,river water pollution ,seasonal changes in pollution ,Renewable Energy, Sustainability and the Environment ,mean daily discharge ,media_common.quotation_subject ,Chemical oxygen demand ,Monsoon ,lcsh:TD1-1066 ,Environmental chemistry ,Dry season ,Environmental science ,Water quality ,lcsh:Environmental technology. Sanitary engineering ,Water pollution ,Ecology, Evolution, Behavior and Systematics ,Wastewater quality indicators ,General Environmental Science ,media_common - Abstract
A study based on the physicochemical parameters and dissolved metals levels from three main rivers around Dhaka City, Bangladesh, was conducted in order to determine the present pollution status and their alteration trends with the seasonal change of discharge amount. The water samples were collected from the rivers Buriganga, Turag, and Shitalakkhya during both dry and monsoon seasons. Physicochemical analyses revealed that most of the water quality parameters exceeded the recommended levels set by the Department of Environment (DoE), Bangladesh, during both the dry and monsoon seasons. A very strong positive correlation was found between biochemical oxygen demand (BOD) and chemical oxygen demand (COD) in all sampling points. Both BOD and COD values had a strong negative correlation with dissolved oxygen (DO) in the Shitalakkhya River. Most of the dissolved metals concentrations in the water samples were similar. However, the concentrations of different physicochemical properties varied with the seasons. The dry season had significantly higher contamination loads, which were decreased during the monsoon season. Anthropogenic activities, as well as the variation in river water flow during different seasons were the main reasons for this high degree of water pollution.
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- 2015
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44. Nonylphenol diethoxylate inhibits apoptosis induced in PC12 cells
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Yongkun Sun, Chuang Liu, Yutong Song, Masaaki Kurasaki, and Takeshi Saito
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0301 basic medicine ,endocrine system ,medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Cellular differentiation ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,Biology ,Toxicology ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Internal medicine ,medicine ,Viability assay ,0105 earth and related environmental sciences ,urogenital system ,Cytochrome c ,General Medicine ,Molecular biology ,Nonylphenol ,Cytosol ,030104 developmental biology ,Endocrinology ,chemistry ,Apoptosis ,Toxicity ,biology.protein ,DNA fragmentation - Abstract
Nonylphenol and short-chain nonylphenol ethoxylates such as NP2 EO are present in aquatic environment as wastewater contaminants, and their toxic effects on aquatic species have been reported. Apoptosis has been shown to be induced by serum deprivation or copper treatment. To understand the toxicity of nonylphenol diethoxylate, we investigated the effects of NP2 EO on apoptosis induced by serum deprivation and copper by using PC12 cell system. Nonylphenol diethoxylate itself showed no toxicity and recovered cell viability from apoptosis. In addition, nonylphenol diethoxylate decreased DNA fragmentation caused by apoptosis in PC12 cells. This phenomenon was confirmed after treating apoptotic PC12 cells with nonylphenol diethoxylate, whereas the cytochrome c release into the cytosol decreased as compared to that in apoptotic cells not treated with nonylphenol diethoxylates. Furthermore, Bax contents in apoptotic cells were reduced after exposure to nonylphenol diethoxylate. Thus, nonylphenol diethoxylate has the opposite effect on apoptosis in PC12 cells compared to nonylphenol, which enhances apoptosis induced by serum deprivation. The difference in structure of the two compounds is hypothesized to be responsible for this phenomenon. These results indicated that nonylphenol diethoxylate has capability to affect cell differentiation and development and has potentially harmful effect on organisms because of its unexpected impact on apoptosis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1389-1398, 2016.
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- 2015
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45. Inhibitory effects of selenium on cadmium-induced cytotoxicity in PC12 cells via regulating oxidative stress and apoptosis
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Tajuddin Sikder, Takeshi Saito, Toshiyuki Hosokawa, Mostafizur Rahman, Masaaki Kurasaki, and Kaniz Fatima Binte Hossain
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0301 basic medicine ,GPX1 ,Programmed cell death ,Cell Survival ,Cells ,Apoptosis ,DNA Fragmentation ,Toxicology ,medicine.disease_cause ,Protective Agents ,PC12 Cells ,03 medical and health sciences ,chemistry.chemical_compound ,Selenium ,Glutathione Peroxidase GPX1 ,medicine ,Autophagy ,Animals ,Cytotoxicity ,chemistry.chemical_classification ,Glutathione Peroxidase ,biology ,Cytochrome c ,Glutathione peroxidase ,Cytochromes c ,General Medicine ,Glutathione ,Molecular biology ,Mitochondria ,Rats ,Oxidative Stress ,030104 developmental biology ,chemistry ,biology.protein ,Reactive Oxygen Species ,Oxidative stress ,Food Science ,Cadmium - Abstract
Purpose of this study is to investigate mechanism/s of cyto-protection by selenium (Na2SeO3; Se4+) against cadmium (CdCl2; Cd2+)-induced cytotoxicity using PC12 cells. In addition, Se (5, 10, 20 and 40 μM) and Cd (2.5, 5 and 10 μM)-induced cytotoxicity is determined. Cytotoxicity assays and western blot analyses confirmed that Se (≥10 μM) promotes autophagic cell death via inhibition of mTOR activation and p62 accumulation due to increase of cellular oxidative stress. On the other hand, co-presence of non-toxic Se (5 μM) and toxic Cd (5 μM) showed to increase cell viability, glutathione and glutathione peroxidase 1 (GPx1) levels, and to decrease DNA fragmentation and lactate dehydrogenase (LDH) activity compared to Cd-treated (5 μM) cells alone. Furthermore, western blot analyses of cytochrome c and ERK1 indicated that Cd-induced apoptotic cell death in PC12 cells. However, the co-exposure of Se with Cd significantly decreases the release of cytochrome c into cytosol from mitochondria, and up-regulates ERK1 protein to inhibit Cd-induced apoptosis. In conclusion, Se (≥10 μM) possess cytotoxicity in PC12 cells; however, co-presence of Se (5 μM) with Cd (5 μM) protects against Cd-induced apoptosis in PC12 cells due to inhibition of Cd-induced oxidative stress and subsequently suppression of mitochondrial apoptosis pathway.
- Published
- 2017
46. Melinjo (Gnetum gnemon) Seed Extract Consumption during Lactation Improved Vasodilation and Attenuated the Development of Hypertension in Female Offspring of Fructose-Fed Pregnant Rats
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Rachael A, Uson-Lopez, Saori, Kataoka, Yuuka, Mukai, Shin, Sato, and Masaaki, Kurasaki
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Male ,Plant Extracts ,Body Weight ,Fructose ,Gnetum ,AMP-Activated Protein Kinases ,Kidney ,Animals, Suckling ,Rats ,Vasodilation ,Pregnancy ,Prenatal Exposure Delayed Effects ,Hypertension ,Seeds ,Animals ,Lactation ,Female - Abstract
Fructose intake has been correlated with increased prevalence of metabolic disorders including hypertension. In pregnant rats, fructose intake has been reported to have adverse effects on the health of its offspring. This study investigated the effects of gestational maternal fructose consumption and if supplementation with melinjo seed extracts to the maternal diet during lactation could benefit the offspring in later life.Pregnant rats were randomly divided into three groups: untreated (CC), fructose-treated (FC), and fructose and melinjo-treated (FM). FC and FM groups received 100 g/L of D(-)-fructose solution by means of the drinking water during gestation while CC received normal drinking water. During lactation, CC and FC groups were given standard commercial laboratory diet, while the FM group was given commercial laboratory diet with 0.1% melinjo seed extracts. After weaning, the offspring were given normal drinking water and standard commercial diet until week 17. The blood pressure of the offspring was monitored until the 16th week. During week 17, the offspring were killed, and the kidneys were collected and analyzed.The level of renal phosphorylated AMP-activated protein kinase (pAMPK) in FM of 17-week female offspring was significantly higher compared with FC and CC groups. Maternal fructose intake down-regulated the renal endothelial isoform of nitric oxide synthetase expression in FC and maternal melinjo seed extract consumption maintained renal endothelial isoform of nitric oxide synthetase expression in FM of 17-week female offspring. In addition, maternal melinjo seed extract intake during lactation lowered the systolic blood pressure in FM of 17-week female offspring.Female offspring were more vulnerable to the effects of placental fructose and melinjo seed extracts, suggesting sex-specific sensitivities. In summary, our data show that melinjo seed extract consumption during lactation improved vasodilation and attenuated the development of hypertension in the 17-week female offspring of fructose-fed pregnant rats. Birth Defects Research 110:27-34, 2018. © 2017 Wiley Periodicals, Inc.
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- 2017
47. Myricetin enhances on apoptosis induced by serum deprivation in PC12 cells mediated by mitochondrial signaling pathway
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Masaaki Kurasaki, Takeshi Saito, Md. Mostafizur Rahman, Rachael A. Uson-Lopez, Gongxun Tan, and Toshiyuki Hosokawa
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0301 basic medicine ,Serum ,DNA damage ,Health, Toxicology and Mutagenesis ,Caspase 3 ,Apoptosis ,DNA Fragmentation ,Toxicology ,PC12 Cells ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Animals ,Caspase ,Pharmacology ,Flavonoids ,biology ,Cytochrome c ,Cytochromes c ,General Medicine ,Caspase 9 ,Cell biology ,Mitochondria ,Rats ,030104 developmental biology ,chemistry ,Proto-Oncogene Proteins c-bcl-2 ,030220 oncology & carcinogenesis ,biology.protein ,DNA fragmentation ,Myricetin ,Apoptotic signaling pathway ,Signal Transduction - Abstract
Polyphenols have many beneficial effects and an effective disease therapeutic auxiliary drug. Previously, myricetin, a polyphenol, had been reported to possess various biological effects on human physiology. However, mechanism of myricetin on apoptosis induced in PC12 cells is still unclear. PC12 cells were treated with myricetin in two concentration levels comprising 0.1 and 1 μM under serum-free condition. As a result, morphological changes were observed using trypan blue assay. DNA fragmentation was determined by DNA ladder assay to evaluate DNA damage levels. Western blotting results showed that cytosolic cytochrome c which was released from mitochondria. Subsequently, tumor suppressor gene p53, pro-apoptotic and anti-apoptotic Bcl-2 family proteins Bax and Bcl-2 were expressed. The caspase cascade reaction was induced through caspase 3 and 9 expression. From these results, it is suggested that myricetin significantly enhanced the apoptosis induced by serum deprivation in a dose-dependent manner in PC12 cells.
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- 2017
48. Changes in the expression of epigenetic factors during copper-induced apoptosis in PC12 cells
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Toshiyuki Hosokawa, Chuang Liu, Masaaki Kurasaki, Yongkun Sun, Yutong Liu, and Takeshi Saito
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Programmed cell death ,Environmental Engineering ,DNA damage ,Sir2 ,Apoptosis ,DNA Fragmentation ,Biology ,medicine.disease_cause ,PC12 Cells ,Epigenesis, Genetic ,medicine ,Animals ,oxidative stress ,Epigenetics ,DNA methylation ,Copper toxicity ,Oxidative Stress Pathway ,Cytochromes c ,Hydrogen Peroxide ,General Medicine ,medicine.disease ,Rats ,Cell biology ,Biochemistry ,DNA fragmentation ,epigenetic ,Copper ,Oxidative stress - Abstract
Despite extensive research on copper toxicity the mechanisms involved are not fully characterized. There have been many recent reports concerning the relationship between epigenetic factors and cell metabolism, but the effects of copper exposure on epigenetic factors have not been investigated. In this study, an in vitro culture system was employed to study the influence of copper on apoptosis and epigenetic factors in PC12 cells. When PC12 cells were exposed to copper, DNA damage was observed as DNA fragmentation. In addition, cytosolic cytochrome c levels were increased by copper treatment. These results suggested that copper induced apoptosis via an oxidative stress pathway. This was consistent with the observation that copper-induced apoptosis was enhanced by further oxidative stress induced by exposing cells to H₂O₂. In addition, the epigenetic factors were significantly increased in apoptotic cells following exposure to copper and oxidative stress.
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- 2014
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49. Effects of peat fires on the characteristics of humic acid extracted from peat soil in Central Kalimantan, Indonesia
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Kazuto Sazawa, Toshiyuki Hosokawa, M. Suhaemi Syawal, Yusuke Kihara, Linda Wulandari, Masaaki Kurasaki, Shunitz Tanaka, Hideki Kuramitz, Yustiawati, Hendri I, and Takeshi Saito
- Subjects
chemistry.chemical_classification ,Elemental composition ,Peat ,Ecology ,Health, Toxicology and Mutagenesis ,Pyrolysis gc ms ,General Medicine ,complex mixtures ,Pollution ,Fires ,Gas Chromatography-Mass Spectrometry ,Molecular Weight ,Spectrometry, Fluorescence ,chemistry ,Indonesia ,Elemental analysis ,Environmental chemistry ,Thermogravimetry ,Environmental Chemistry ,Humic acid ,Ecotoxicology ,Organic matter ,Humic Substances - Abstract
When peat forest fires happen, it leads to burn soil and also humic acids as a dominant organic matter contained in peat soil as well as the forest. The structure and properties of humic acids vary depending on their origin and environment, therefore the transformation of humic acid is also diverse. The impacts of the peat fires on peat soil from Central Kalimantan, Indonesia were investigated through the characterization of humic acids, extracted from soil in burnt and unburnt sites. The characterization of humic acids was performed by elemental composition, functional groups, molecular weight by HPSEC, pyrolysate compounds by pyrolysis-GC/MS, fluorescence spectrum by 3DEEM spectrofluorometer, and thermogravimetry. The elemental composition of each humic substance indicated that the value of H/C and O/C of humic acids from burnt sites were lower than that from unburnt sites. The molecular weight of humic acids from burnt sites was also lower than that from unburnt sites. Pyrolysate compounds of humic acids from unburnt sites differed from those of humic acids from burnt soil. The heating experiment showed that burning process caused the significant change in the properties of humic acids such as increasing the aromaticity and decreasing the molecular weight.
- Published
- 2014
- Full Text
- View/download PDF
50. Effect ofTinospora cordifoliaon the reduction of ultraviolet radiation‐induced cytotoxicity and DNA damage in PC12 cells
- Author
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Runa Masuma, Mohammad Shahabuddin Kabir Choudhuri, Masaaki Kurasaki, Tsutomu Okuno, and Takeshi Saito
- Subjects
Tinospora ,Cell Survival ,Ultraviolet Rays ,DNA damage ,Drug Evaluation, Preclinical ,Enzyme-Linked Immunosorbent Assay ,Radiation-Protective Agents ,Pyrimidine dimer ,Biology ,Tinospora cordifolia ,PC12 Cells ,Animals ,Viability assay ,Irradiation ,Cytotoxicity ,Ultraviolet radiation ,Electrophoresis, Agar Gel ,Plants, Medicinal ,Dose-Response Relationship, Drug ,Plant Extracts ,General Medicine ,biology.organism_classification ,Pollution ,Molecular biology ,Rats ,Biochemistry ,Pyrimidine Dimers ,Agarose gel electrophoresis ,DNA Damage ,Food Science - Abstract
The safety of Tinospora cordifolia and its potential to protect against ultraviolet radiation-induced cytotoxicity and DNA damage in PC12 cells were investigated. To evaluate the safety of T. cordifolia, cell viability and agarose gel electrophoresis were carried out using PC12 cells treated with 0 to 100 μg mL(-1) of methanol extract of T. cordifolia. T. cordifolia extracts did not show cytotoxicity ranging 0 to 100 μg mL(-1). In addition, T. cordifolia extracts significantly increased cell viability at 1 ng, 10 ng and 1 μg mL(-1) concentrations in serum-deprived medium compared to control. To confirm the protective role against UV-induced damage, PC12 cells alone or in the presence of 10 ng, 100 ng, or 1 μg mL(-1) of T. cordifolia extract were exposed to 250, 270 and 290 nm of UV radiation, which corresponded to doses of 120, 150 and 300 mJ cm(-2), respectively. Treatment with T. cordifolia extracts significantly increased the cell survival rate irradiated at 290 nm. In addition, T. cordifolia extracts significantly reduced cyclobutane pyrimidine dimer formation induced by UV irradiation at all wavelengths. In conclusion, T. cordifolia is not toxic and safe for cells. Our findings can support its application as phototherapy in the medical sector.
- Published
- 2014
- Full Text
- View/download PDF
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