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1.
Mol Biotechnol ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907811

RESUMO

The present study focused on preparing and characterizing magnetite-polyvinyl alcohol (PVA) hybrid nanoparticles using Acanthophora spicifera marine algae extract as a reducing agent. Various analytical techniques, including UV-Visible spectrometry, Fourier-transform infrared (FTIR) analysis, energy-dispersive X-ray (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis, were used to characterize the nanoparticles. The results showed the successful synthesis of nanoparticles with a characteristic color change and absorption peak at 400 nm in UV-Visible spectrometry. FTIR analysis indicated an interaction between the carboxyl group and magnetite-polyvinyl alcohol hybrid ions. SEM analysis revealed spherical nanoparticles with sizes ranging from 20 to 100 nm. EDX analysis confirmed the presence of strong magnetite peaks in Acanthophora spicifera, validating successful preparation. XRD analysis indicated the crystalline nature of the nanoparticles. Furthermore, the antimicrobial potential of As-PVA-MNPs was evaluated, demonstrating a significant zone of inhibition against tested bacterial and fungal samples at a concentration of 100 µg. These findings suggest the promising antimicrobial activity of the synthesized nanoparticles for potential applications in combating pathogenic microorganisms.

3.
RSC Adv ; 12(3): 1287-1309, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35425201

RESUMO

The economic viability of CO2 reactors is contingent on the selectivity of the CO2 reduction reaction and the rate of product formation. For this, the rational design of electrolyzers also has a substantial impact on the figures of merit (current density, faradaic efficiency, cell durability). Thus, herein we portray a short review on the shortcomings, challenges and the recent developments on different reactor configurations, components and membrane structures for the efficient electrochemical CO2 reduction (CO2R) into HCOO-/HCOOH. Despite their low CO2 solubility and poor mass transport, H-type electrolyzers are commercialized due to their screening of a vast number of catalysts. In contrast, membrane-based gas and liquid phase flow reactors break the barriers faced by H-types through the incorporation of gas diffusion electrodes (GDEs) and the membrane electrode assembly (MEA). As the GDE forms the gas-liquid-solid interface, it allows the electrolyzers to generate current densities at the industrial level (200 mA cm-2). Intriguingly, a continuous liquid fed intermittent flow electrolyzer can control the electrolyte flow at a desired frequency and allow sufficient time for CO2 gas molecules to effectively reduce into HCOOH. Therefore, a high and stable faradaic efficiency (95%) is achieved in 4 h for HCOOH (576.98 mg) using the boron-doped diamond catalyst. Very recently, a novel strategy to enhance the CO2R to HCOO-/HCOOH has been adopted via the recirculation of by-products to the liquid phase MEA flow reactors, which substantially improves HCOO- selectivity, lowers material costs, and promotes CO2 mass transfer. In the end, the zero-gap electrolyzer has newly emerged and affords reduced ohmic losses, leading to a straight-forward implementation of industrial systems for CO2R to value-added products in the future. Besides, the efficiency of HCOO-/HCOOH production is also explored against proton exchange, anion exchange and bipolar membranes, and the pH of the electrolyte plays a dominant role in deciding the stability and characteristics of the membranes. It is also depicted that the product selectivity depends on different electrolyzer configurations. Recently, bimetallic alloys (Bi-Sn, Bi-In) and 2D layered composites (SnO2/rGO/CNT) have proven to be potential electrocatalysts (faradaic efficiency > 95%, highly selective and durable) assigned to the abundant active sites for CO2R. Based on the recent findings and future research directions, we draw reader's attention to construct economic, scalable and energy-efficient CO2R electrolyzers to realize the techno-economic predictions.

4.
Chemosphere ; 287(Pt 2): 132164, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34509762

RESUMO

Synthetic dyes are among the common pollutants in the ecosystem. In the present study, polypyrrole/zeolite (PPy/Ze) nanocomposite was prepared and subsequently assessed for the removal of Reactive blue (RB) and Reactive red (RR) from synthetic solution. The polymeric PPy/Ze composite was synthesized by chemical oxidation of pyrrole in the presence of zeolite. Electron microscopic images (transmission and scanning) indicate that PPy/Ze nanocomposite was spherical in shape with an average size of 40-80 nm. The characteristic pyrrole and zeolite Fourier transform infrared spectrum peaks (1542 cm-1, 1463 cm-1, 1156 cm-1, 1054 cm-1, 879 cm-1 and 756 cm-1) in the nanocomposite confirmed zeolite integration with polypyrrole. Experimental variables such as PPy/Ze nanocomposite dose, initial RB and RR concentration, reaction temperature and pH were optimized. The PPy/Ze nanocomposite adsorbed 86.2% of RB and 88.3% of RR from synthetic solution at optimal conditions (pH 9, initial RR or RB concentration, 75 mg/l; PPy/Ze dose, 1.8 g/l; and temperature, 50 °C). Freundlich isotherm model and pseudo-second-order kinetics showed better fit for both RB and RR removal from synthetic solution. X-ray diffractogram confirmed the amorphous nature of PPy/Ze nanocomposite and that it was not altered even after dye adsorption. Adsorption-desorption studies showed that the composite has satisfactory adsorption potential for four cycles. The results show that the PPy/Ze nanocomposite could be used for the removal of dyes from wastewaters.


Assuntos
Poluentes Químicos da Água , Zeolitas , Adsorção , Corantes , Ecossistema , Cinética , Polímeros , Pirróis
5.
Polymers (Basel) ; 13(19)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34641118

RESUMO

Polyhydroxyalkanoates (PHAs) are storage granules found in bacteria that are essentially hydroxy fatty acid polyesters. PHA molecules appear in variety of structures, and amongst all types of PHAs, polyhydroxybutyrate (PHB) is used in versatile fields as it is a biodegradable, biocompatible, and ecologically safe thermoplastic. The unique physicochemical characteristics of these PHAs have made them applicable in nanotechnology, tissue engineering, and other biomedical applications. In this review, the optimization, extraction, and characterization of PHAs are described. Their production and application in nanotechnology are also portrayed in this review, and the precise and various production methods of PHA-based nanoparticles, such as emulsion solvent diffusion, nanoprecipitation, and dialysis are discussed. The characterization techniques such as UV-Vis, FTIR, SEM, Zeta Potential, and XRD are also elaborated.

6.
Microb Pathog ; 157: 105007, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34044052

RESUMO

Screening of halophiles with antimicrobial activity in saltpan soil samples from Nagapattinam district, Tamil Nadu, revealed isolate VE-2 as the most potent, identified as Bacillus firmus strain VE-2 through 16s rRNA gene sequencing. It had an optimum growth condition (OD 3.1) and antimicrobial protein (AMP) production (450 µg/mL) at 37 °C, pH 8, 25% NaCl, and 36 h incubation. SDS-PAGE analysis of the purified AMP showed the molecular weight of 36 kDa. HPLC analysis of the purified AMP showed different amino acids, such as asparagines, alanine, lysine, proline, threonine, glycine, cysteine, serine, aspartic acid leucine, and valine. Further characterization and identification using FT-IR, 2D-PAGE, MALDI-TOF, and in-silico analysis showed that the isolated AMP had the highest similarity to Subtilisin-A. It showed antibacterial activity against clinical bacterial pathogens like S. aureus, S. pyogenes, C. diphtheria, E. coli, and P. aeruginosa with the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration of 2.5 µg/mL and 20 µg/mL and also against various fungal pathogens such as A. niger, A. flavus, C. albicans, C. tropicalis and C. parapsilosis with the MIC and minimum fungicidal concentrations of 1.25-80 µg/mL. The purified AMP had excellent antioxidant potential, showed a scavenging effect against DPPH and Nitric oxide radicals, and displayed anticancer activity against HeLa cell lines with the IC50 values 53 µg/mL. Hence, the purified bioactive antimicrobial peptides (AMP) could also be used in anticancer therapies.


Assuntos
Bacillus firmus , Subtilisina/farmacologia , Antibacterianos/farmacologia , Escherichia coli , Células HeLa , Humanos , Índia , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus
7.
Chemosphere ; 267: 129201, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33338713

RESUMO

Dyes and heavy metals pollution have become a major environmental concern worldwide. Various methods, such as advanced oxidation, biodegradation, precipitation, flocculation, ultra filtration, ion-exchange, electro-chemical degradation and coagulation, have been proposed for the removal of dyes and heavy metals from contaminated wastewater. Of these methods, adsorption and detoxification are considered as the most promising and economically viable. Polyaniline-based composites, a material prepared by combining polyaniline with one or more similar or disimilar materials, have been reported as good adsorbents to remove and detoxify different groups of pollutants due to their unique physical and chemical properties. In the last decade, several studies have reported the effective adsorption (∼95%) of dyes and heavy metals onto polyaniline based composites. Furthermore, some polyaniline -composites reduced the adsorbed heavy metals into less toxic state. This review compiles the application of different polyaniline composites for adsorption and/or detoxifcation of dyes and heavy metals and documents composite preparation methods, morphology and properties of the composites, and mechanism of dyes and heavy metals adsorption. Based on the avilabile literature, this review suggests that more studies are warranted to understand the influence of various conditions and experimental variables on dyes and heavy metals removal from wastewater and/or aqueous solution.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Compostos de Anilina , Corantes , Águas Residuárias , Poluentes Químicos da Água/análise
8.
Physiol Mol Biol Plants ; 26(10): 2053-2060, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33088049

RESUMO

Tea (Camellia sinensis (L.) O.Kuntze) is an industry-oriented economical crop in India. Among the sap sucking pests, tea mosquito bug (Helopeltis theivora) is one of the most serious pests causing heavy crop loss in tea plantation. Continuous use of chemical pesticides causes environmental pollution and health hazards besides developing pesticide residues in tea powder. The control of pests by bacterial metabolite is an alternative that may contribute to reduce or eliminate the chemical pesticide use. The use of chitinase as a biological control is an emerging field of research. In the present study, Chitinase (~ 25 kDa) was purified from Bacillus cereus C-13 strain using gel-filtration chromatography and further characterized for its optimum pH, temperature and substrate specificity. Bioefficacy of chitinase from B. cereus C-13 was compared with our previously reported Pseudomonas fluorescens MP-13 chitinase against H. theivora. Result concluded that, 100% and 78% mortality was observed by using P. fluorescens MP-13 chitinase and B. cereus C-13 chitinase, respectively. In future, bacterial chitinase can be utilized in eco-friendly pest management strategies.

9.
Int J Biol Macromol ; 141: 290-298, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31476395

RESUMO

In this study, a novel ecofriendly chitosan- silver nanoparticles hybrid was developed. Biological method using leaf extract of T. portulacifolium was used as reducing agent for its synthesis and the antibacterial efficiency of these hybrid nanoparticles were evaluated against the bacteria E. coli and S. marcescens organisms. The intense peak observed around 419 nm in the UV-Vis indicates the formation of silver nanoparticles. The XRD analysis showed that the hybrid chitosan-silver nanoparticles have a polycrystalline and face-centered cubic configuration. FTIR spectrum hybrid chitosan-silver nanoparticles indicated speaks vibration of NH and OH. The EDS analysis confirmed the presence of Ag, O, C and N elements in the prepared sample. The spherical shape was obtained from TEM analysis and it indicated that with average particles around 3.24 nm to 44.80 nm. The prepared hybrid chitosan-silver nanoparticles showed significant antibacterial activities against E. coli and S. marcescens. In addition, the surface membrane damages and surface morphology of test pathogens were visualized using FESEM analysis.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Quitosana , Nanopartículas Metálicas , Prata , Quitosana/química , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Modelos Biológicos , Compostos Fitoquímicos/química , Extratos Vegetais/química , Prata/química , Análise Espectral
10.
Phys Chem Chem Phys ; 21(7): 4032-4045, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30720029

RESUMO

The enriched ferromagnetism and two-photon absorption (TPA) cross-section of perovskite BaTiO3 nanoparticles are indispensable for magnetic and optical data storage applications. In this work, hydrothermally synthesized Ce-doped BaTiO3 nanoparticles exhibited the maximum room temperature ferromagnetism (4.26 × 10-3 emu g-1) at 4 mol% due to the increase in oxygen vacancies, as evidenced by X-ray photoelectron and electron spin resonance spectroscopy and density functional theory (DFT) calculations. Hence, the oxygen vacancy-constituted bound magnetic polaron (BMP) model was invoked to explain the enhancement in ferromagnetism. The BMP theoretical model indicated an increase in BMP magnetization (M0, 3.0 to 4.8 × 10-3 emu g-1) and true spontaneous moment per BMP (meff, 4 to 9.88 × 10-4 emu) upon Ce doping. DFT calculations showed that BMPs mediate via the Ti dz2 orbitals, leading to ferromagnetism. Besides, it is known that the magnetic moment induced by Ce at the Ba site is higher than Ce at the Ti site in the presence of oxygen vacancies. The open aperture Z-scan technique displayed the highest TPA coefficient, ß (7.08 × 10-10 m W-1), and TPA cross-section, σTPA (455 × 104 GM), at 4 mol% of Ce as a result of the robust TPA-induced excited state absorption. The large σTPA is attributed to the longer excited state lifetime, τ (7.63 ns), of the charge carriers created by oxygen vacancies and Ce ions, which encounter several electronic transitions in the excited sub-states.

12.
J Photochem Photobiol B ; 179: 119-125, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29367146

RESUMO

In the present day, nanotechnology is one of the most promising leading scientific and potentials areas in modern key technology development toward to the humankind. The synthesis of noble metal nanoparticles (NPs) is an expanding research area due to the possible applications for the development of bio-medical applications. Eco-friendly approach for the biosynthesis of gold nanoparticles (AuNPs) using the aqueous extract from Ruellia tuberosa and Phyllanthus acidus (leaf and twig) for the first time. Surface active AuNPs were characterized by UV-Vis spectroscopy, FTIR (Fourier transform infrared) spectroscopy, DSC (differential scanning colorimetry), DLS (dynamic light scattering) and environmental SEM (scanning electron microscope) analysis at room temperature (RT). Enhanced surface plasmon resonance (SPR) absorbance UV visible optical spectra were detected in the range of 552, 548, 558 and 536 nm. SEM and DLS (transmission mode) analysis confirmed the morphology of the nanoparticles to be spherical with the average size in the range of 88.37, 94.31, 82.23 and 81.36 nm. Further they have enhanced the enzyme activity on α-amylase, cellulase, and xylanase. The results suggest that the phyto-fabricated AuNPs from R. tuberosa and P. acidus is simple, less expensive, eco-friendly, green synthesis and also can be exploited for the potential future industrial and bio-medical applications.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Acanthaceae/química , Acanthaceae/metabolismo , Difusão Dinâmica da Luz , Química Verde , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Phyllanthus/química , Phyllanthus/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Ressonância de Plasmônio de Superfície
13.
Regul Toxicol Pharmacol ; 92: 189-200, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29242155

RESUMO

The influence of exposure duration on chemical toxicity has important implications for risk assessment. Although a default 10-fold extrapolation factor is commonly applied when the toxicological dataset includes a subchronic (90-day) study but lacks studies of chronic duration, little consensus has been reached on an appropriate extrapolation factor to apply when the dataset includes a 28-day study but lacks studies of longer durations. The goal of the present assessment was to identify a 28-day to 90-day extrapolation factor by analyzing distributions of ratios of No-Observed-Adverse-Effect Levels (NOAELs) and Benchmark Doses (BMDs) derived from 28-day and 90-day studies. The results of this analysis suggest that a default 10-fold extrapolation factor in chemical risk assessment applications is sufficient to account for the uncertainty associated with evaluating human health risk based on results from a 28-day study in the absence of results from a 90-day study. This analysis adds significantly to the growing body of literature interpreting the influence of exposure duration on chemical toxicity that will likewise facilitate discussions on the future state of testing requirements in the international regulatory community.


Assuntos
Substâncias Perigosas/administração & dosagem , Substâncias Perigosas/toxicidade , Animais , Benchmarking/métodos , Relação Dose-Resposta a Droga , Humanos , Nível de Efeito Adverso não Observado , Medição de Risco/métodos , Fatores de Tempo , Incerteza
14.
J Gen Appl Microbiol ; 63(4): 222-227, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28680004

RESUMO

The tea mosquito bug (TMB), Helopeltis spp. (Hemiptera: Miridae) is an insidious pest that poses a significant economical threat to tea plantations. Pseudomonas cultures are being used extensively for pest management which, however, resulting in a low mortality rate of insects and which has prompted us to search for a new microbial metabolite for TMB control. A chitinase purified from P. fluorescens and partially characterized by our group showed insecticidal activity against TMB. The mode of action behind chitinase toxicity is the enzymatic hydrolysis of chitin, which is a common constituent of the insect exoskeleton and gut lining of the peritrophic membrane. A chitinase-secreting strain MP-13 was characterized based on 16S rRNA sequencing and validated as Pseudomonas fluorescens. In the present study, purified chitinase (0.048 units/ml) enzyme from P. fluorescens MP-13 revealed 100% TMB mortality under in-vitro conditions. The results of this study can be utilized for future crop improvement programs and integrated pest management strategies.


Assuntos
Proteínas de Bactérias/farmacologia , Quitinases/farmacologia , Heterópteros/efeitos dos fármacos , Inseticidas/farmacologia , Pseudomonas fluorescens/enzimologia , Animais , Quitina/metabolismo , Quitinases/toxicidade , Inseticidas/toxicidade , Controle Biológico de Vetores , Pseudomonas fluorescens/classificação , RNA Ribossômico 16S/genética
15.
Indian J Cancer ; 54(4): 652-657, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30082552

RESUMO

PURPOSE: The objective of this study was to assess response to neoadjuvant chemotherapy in molecular subtypes of breast cancer. METHODS: This study included 60 patients with locally advanced and metastatic breast cancer. The authors excluded patients who already underwent mastectomy or were given any chemotherapy/radiotherapy. They analyzed the clinical and immunohistochemical characteristics using core biopsy specimens to determine their correlations with response to chemotherapy. RESULTS: A clinical complete response was observed in 19 patients (31.7%), a clinical partial response in 30 patients (50%), clinical stable disease in 8 patients (13.3%), and progressive disease in 3 patients (5%). A pathologic complete response (pCR) was observed in 7 (21.87%) of 32 patients who underwent surgery. High Ki-67 was associated with human epidermal growth factor receptor 2 (HER2)-positive status (P = 0.027) and triple-negative breast cancer (TNBC) (P = 0.006). Multiple logistic regression analysis showed that pCR was correlated with HER2 status (odds ratio 26.589, confidence interval [CI] =1.606-44.190), P = 0.022. Of the seven patients found to have pCR, six patients (85.7%) were treated with taxol-containing regimen. The other parameters that were correlated with pCR are TNBC and estrogen receptor/progesterone receptor status. Tumor size, Ki-67 value, and grade of the tumor were not correlated with clinical response. CONCLUSION: Molecular subtype in breast cancer is an effective factor for predicting response to neoadjuvant chemotherapy. HER2-positive status was associated with high Ki-67 and high clinical and pathological response rate. Taxol needs to be added in neoadjuvant chemotherapy to improve pCR. Luminal subtypes respond poorly to chemotherapy.


Assuntos
Neoplasias da Mama/cirurgia , Terapia Neoadjuvante/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/cirurgia , Adulto , Idoso , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Feminino , Humanos , Antígeno Ki-67/genética , Mastectomia/efeitos adversos , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Receptor ErbB-2/genética , Receptores de Progesterona/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia
17.
Environ Sci Pollut Res Int ; 23(3): 2173-85, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26330309

RESUMO

PCBs are persistent organic pollutants that are carcinogenic and immunotoxic and have developmental toxicity. This suggests that they may interfere with normal cell maturation. Cancer and stem/progenitor cells have telomerase activity to maintain and protect the chromosome ends, but lose this activity during differentiation. We hypothesized that PCBs interfere with telomerase activity and the telomere complex, thereby disturbing cell differentiation and stem/progenitor cell function. HL-60 cells are cancer cells that can differentiated into granulocytes and monocytes. We exposed HL-60 cells to PCB126 (dioxin-like) and PCB153 (nondioxin-like) 6 days before and during 3 days of differentiation. The differentiated cells showed G0/G1 phase arrest and very low telomerase activity. hTERT and hTR, two telomerase-related genes, were downregulated. The telomere shelterins TRF1, TRF2, and POT1 were upregulated in granulocytes, and TRF2 was upregulated and POT1 downregulated in monocytes. Both PCBs further reduced telomerase activity in differentiated cells, but had only small effects on the differentiation and telomere-related genes. Treatment of undifferentiated HL-60 cells for 30 days with PCB126 produced a downregulation of telomerase activity and a decrease of hTERT, hTR, TRF1, and POT1 gene expression. With PCB153, the effects were less pronounced and some shelterin genes were increased after 30 days of exposure. With each PCB, no differentiation of cells was observed and cells continued to proliferate despite reduced telomerase activity, resulting in shortened telomeres after 30 days of exposure. These results indicate cell-type and PCB congener-specific effects on telomere/telomerase-related genes. Although PCBs do not seem to strongly affect differentiation, they may influence stem or progenitor cells through telomere attrition with potential long-term consequences for health.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Bifenilos Policlorados/toxicidade , Telomerase/antagonistas & inibidores , Telômero/metabolismo , Inibidores Enzimáticos/química , Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Bifenilos Policlorados/química , Telomerase/genética , Telomerase/metabolismo
18.
Indian J Psychol Med ; 37(3): 277-81, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26664075

RESUMO

BACKGROUND: While western studies have focused on the importance of psychiatric illnesses in the complex pathways leading to suicides, several Indian studies have highlighted the important contributions by economic, social, and cultural factors. Hence, we tested the hypothesis that annual national suicide rates and suicide rates of the different states in India were associated with macroeconomic indices. MATERIALS AND METHODS: Data from the National crime records bureau, Ministry of finance, labour bureau, Government of India, population commission, and planning commission official portals, World Bank and the United Nations were accessed. We assessed the correlations of annual national and state-wise suicide rates with macroeconomic, health, and other indices using ecological study design for India, and for its different states and union territories. RESULTS: We documented statistically significant associations between the suicide rates and per capita gross domestic product, consumer price index, foreign exchange, trade balance, total health expenditure as well as literacy rates. CONCLUSIONS: As recent economic growth in India is associated with increasing suicide rates, macroeconomic policies emphasizing equitable distribution of resources may help curtailing the population suicide rates in India.

20.
Int J Toxicol ; 34(5): 384-92, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26268770

RESUMO

Although several studies have shown that chemically mediated epigenetic changes are an etiological factor in several human disease conditions, the utility of epigenetic data, such as DNA methylation, in the current human health risk assessment paradigm is unclear. The objective of this study is to investigate the relationship between the points of departure (PODs) for cancer incidence and DNA methylation changes in laboratory animals exposed to the following environmental toxicants: bromodichloromethane, dibromochloromethane, chloroform, hydrazine, trichloroethylene, benzidine, trichloroacetic acid, and di(2-ethylhexyl) phthalate (DEHP; a known reproductive toxicant). The results demonstrate that the PODs for cancer incidence and altered DNA methylation are similar. Furthermore, based on the available data, the POD for DNA methylation appeared more sensitive compared to that for cancer incidence following the administration of DEHP to rats during different life stages. The high degree of correlation between PODs for cancer incidence and DNA methylation (for both total DNA and individual genes) suggests that DNA methylation end points could potentially be used as a screening tool in predicting the potential toxicity/carcinogenicity and in prioritizing large numbers of chemicals with sparse toxicity databases. The life stage during which treatment occurs is also an important consideration when assessing the potential application of epigenetic end points as a screening tool.


Assuntos
Carcinógenos/toxicidade , Metilação de DNA , Epigênese Genética , Animais , Benzidinas/toxicidade , Dietilexilftalato/toxicidade , Humanos , Hidrazinas/toxicidade , Hidrocarbonetos Halogenados/toxicidade , Neoplasias/induzido quimicamente , Neoplasias/genética , Medição de Risco
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