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1.
Nutrients ; 14(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35889957

RESUMO

We evaluated the relationship of urinary sodium excretion with a conditional mean, 10th and 90th percentiles of body mass index (BMI), and waist circumference among 10,034 person-visits of Bangladeshi population. We fitted linear mixed models with participant-level random intercept and restricted maximum likelihood estimation for conditional mean models; and quantile mixed-effect models with participant-level random intercept and Laplace estimation for 10th and 90th percentiles models. For each 100 mmol/24 h increase in urinary sodium excretion, participants had a 0.10 kg/m2 (95% CI: 0.00, 0.10) increase in the mean; a 0.39 kg/m2 (95% CI: 0.23, 0.54) increase in the 10th percentile; and a 0.59 kg/m2 (95% CI: 0.39, 0.78) increase in the 90th percentile of BMI. For each 100 mmol/24 h increase in urinary sodium excretion, participants had a 0.20 cm (95% CI: 0.10, 0.30) increase in mean; a 0.18 cm (95% CI: -0.03, 0.40) change in the 10th percentile; and a 0.23 cm (95% CI: 0.03, 0.43) increase in the 90th percentile of waist circumference. We found a modest association between urine sodium and conditional mean of BMI and waist circumference. The magnitude of associations between urine sodium and the 10th and 90th percentile BMI distributions were higher compared to the conditional mean models, suggesting high sodium intake could be more detrimental to underweight and obese participants.


Assuntos
Obesidade , Sódio , Adulto , Biomarcadores , Índice de Massa Corporal , Estudos de Coortes , Humanos , Obesidade/epidemiologia , Circunferência da Cintura
2.
Lancet Planet Health ; 5(12): e905-e920, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34895498

RESUMO

Electronic waste (e-waste) contains numerous chemicals harmful to human and ecological health. To update a 2013 review assessing adverse human health consequences of exposure to e-waste, we systematically reviewed studies reporting effects on humans related to e-waste exposure. We searched EMBASE, PsycNET, Web of Science, CINAHL, and PubMed for articles published between Dec 18, 2012, and Jan 28, 2020, restricting our search to publications in English. Of the 5645 records identified, we included 70 studies that met the preset criteria. People living in e-waste exposed regions had significantly elevated levels of heavy metals and persistent organic pollutants. Children and pregnant women were especially susceptible during the critical periods of exposure that detrimentally affect diverse biological systems and organs. Elevated toxic chemicals negatively impact on neonatal growth indices and hormone level alterations in e-waste exposed populations. We recorded possible connections between chronic exposure to e-waste and DNA lesions, telomere attrition, inhibited vaccine responsiveness, elevated oxidative stress, and altered immune function. The existence of various toxic chemicals in e-waste recycling areas impose plausible adverse health outcomes. Novel cost-effective methods for safe recycling operations need to be employed in e-waste sites to ensure the health and safety of vulnerable populations.


Assuntos
Resíduo Eletrônico , Metais Pesados , Adulto , Criança , Resíduo Eletrônico/análise , Resíduo Eletrônico/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Masculino , Metais Pesados/análise , Metais Pesados/toxicidade , Gravidez , Reciclagem
3.
Am J Trop Med Hyg ; 104(3): 874-883, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33534756

RESUMO

In low- and middle-income countries (LMICs), hand sanitizer may be a convenient alternative to soap and water to increase hand hygiene practices. We explored perceptions, acceptability, and use of hand sanitizer in rural Bangladesh. We enrolled 120 households from three rural villages. Promoters distributed free alcohol-based hand sanitizer, installed handwashing stations (bucket with tap, stand, basin, and bottle for soapy water), and conducted household visits and community meetings. During Phase 1, promoters recommended handwashing with soap or soapy water, or hand sanitizer after defecation, after cleaning a child's anus/feces, and before food preparation. In Phase 2, they recommended separate key times for hand sanitizer: before touching a child ≤ 6 months and after returning home. Three to 4 months after each intervention phase, we conducted a survey, in-depth interviews, and group discussions with child caregivers and male household members. After Phase 1, 82/89 (92%) households reported handwashing with soap after defecation versus 38 (43%) reported hand sanitizer use. Participants thought soap and water removed dirt from their hands, whereas hand sanitizer killed germs. In Phase 2, 76/87 (87%) reported using hand sanitizer after returning home and 71/87 (82%) before touching a child ≤ 6 months. Qualitative study participants reported that Phase 2-recommended times for hand sanitizer use were acceptable, but handwashing with soap was preferred over hand sanitizer when there was uncertainty over choosing between the two. Hand sanitizer use was liked by household members and has potential for use in LMICs, including during the coronavirus pandemic.


Assuntos
Álcoois/química , Higiene das Mãos/métodos , Higienizadores de Mão/análise , População Rural/estatística & dados numéricos , Adolescente , Adulto , Idoso , Bangladesh/epidemiologia , Características da Família , Feminino , Desinfecção das Mãos/métodos , Desinfecção das Mãos/normas , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pobreza , Pesquisa Qualitativa , Adulto Jovem
4.
Hum Exp Toxicol ; 37(5): 496-507, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28621211

RESUMO

Physicochemical properties of titanium dioxide nanoparticles (TiO2 NPs) can be tuned by doping with metals or nonmetals. Copper (Cu) doping improved the photocatalytic behavior of TiO2 NPs that can be applied in various fields such as environmental remediation and nanomedicine. However, interaction of Cu-doped TiO2 NPs with human cells is scarce. This study was designed to explore the role of Cu doping in cytotoxic response of TiO2 NPs in human lung epithelial (A549) cells. Characterization data demonstrated the presence of both TiO2 and Cu in Cu-doped TiO2 NPs with high-quality lattice fringes without any distortion. The size of Cu-doped TiO2 NPs (24 nm) was lower than pure TiO2 NPs (30 nm). Biological results showed that both pure and Cu-doped TiO2 NPs induced cytotoxicity and oxidative stress in a dose-dependent manner. Low mitochondrial membrane potential and higher caspase-3 enzyme (apoptotic markers) activity were also observed in A549 cells exposed to pure and Cu-doped TiO2 NPs. We further observed that cytotoxicity caused by Cu-doped TiO2 NPs was higher than pure TiO2 NPs. Moreover, antioxidant N-acetyl cysteine effectively prevented the reactive oxygen species generation, glutathione depletion, and cell viability reduction caused by Cu-doped TiO2 NPs. This is the first report showing that Cu-doped TiO2 NPs induced cytotoxicity and oxidative stress in A549 cells. This study warranted further research to explore the role of Cu doping in toxicity mechanisms of TiO2 NPs.


Assuntos
Cobre/toxicidade , Nanopartículas/toxicidade , Titânio/toxicidade , Células A549 , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
5.
BMC Public Health ; 17(1): 392, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28476100

RESUMO

BACKGROUND: Health programs commonly promote handwashing by drawing attention to potential fecal contamination in the environment. The underlying assumption is that the thought of fecal contamination will result in disgust, and motivate people to wash their hands with soap. However, this has not proven sufficient to achieve high rates of handwashing with soap at key times. We argue that handwashing with soap is influenced by broader range of antecedents, many unrelated to fecal contamination, that indicate to people when and where to wash their hands. This exploratory study aimed to identify and characterize this broader range of handwashing antecedents for use in future handwashing promotion efforts. METHODS: First, an initial list of behavioral antecedents was elicited through unstructured interviews, focus group discussions and observation with residents, from a low-income community in Dhaka, Bangladesh, who were also recipients of a handwashing intervention. Then, photographs representing three categories of behavioral antecedents were taken: activities of daily living, visual or tactile sensations, and handwashing-related hardware and activities. Finally, the research team conducted ranking exercises with a new set of participants, from the same area, to assess the perceived importance of each antecedent illustrated by the photographs. The research team probed about perceptions regarding how and why that particular antecedent, represented by the photograph, influences handwashing behavior. RESULTS: After coming out of the bathroom and dirt (moyla) on hands were the two antecedents that ranked highest. In all the categories, intervention-related antecedents (three key times for handwashing which included handwashing after coming out of the bathroom, after cleaning a child's anus and before food preparation; intervention provided items that included handwashing station, soapy water bottle, handwashing reminders from posters and community health provider visits) that were being promoted actively in this community were perceived favorably in the qualitative responses, but did not consistently rank higher than non-intervention items. However, many other antecedents were reported to influence when and where people wash their hands: cutting greasy fish, starting a meal, contact with oil and fat stuck to dishes, oil and lice from hair, sweat, unwashed vegetables, reminders from son and daughter or observing others wash hands, and observing the sunset. CONCLUSIONS: Beyond well-recognized antecedents related to fecal contact and dirt on hands, we identified a broader set of antecedents not reported in the literature. Adopting a handwashing promotional strategy to highlight existing antecedents that people themselves have identified as important can help inform the content of an intervention that is more relatable and effective in increasing handwashing practices.


Assuntos
Desinfecção das Mãos , Comportamentos Relacionados com a Saúde , Sabões , Adulto , Bangladesh , Fezes , Feminino , Grupos Focais , Humanos , Masculino , Motivação , Saúde Pública , Fatores Socioeconômicos , Adulto Jovem
6.
Food Nutr Bull ; 37(2): 186-201, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26944506

RESUMO

BACKGROUND: Contaminated complementary foods are associated with diarrhea and malnutrition among children aged 6 to 24 months. However, existing complementary food safety intervention models are likely not scalable and sustainable. OBJECTIVE: To understand current behaviors, motivations for these behaviors, and the potential barriers to behavior change and to identify one or two simple actions that can address one or few food contamination pathways and have potential to be sustainably delivered to a larger population. METHODS: Data were collected from 2 rural sites in Bangladesh through semistructured observations (12), video observations (12), in-depth interviews (18), and focus group discussions (3). RESULTS: Although mothers report preparing dedicated foods for children, observations show that these are not separate from family foods. Children are regularly fed store-bought foods that are perceived to be bad for children. Mothers explained that long storage durations, summer temperatures, flies, animals, uncovered food, and unclean utensils are threats to food safety. Covering foods, storing foods on elevated surfaces, and reheating foods before consumption are methods believed to keep food safe. Locally made cabinet-like hardware is perceived to be acceptable solution to address reported food safety threats. CONCLUSION: Conventional approaches that include teaching food safety and highlighting benefits such as reduced contamination may be a disincentive for rural mothers who need solutions for their physical environment. We propose extending existing beneficial behaviors by addressing local preferences of taste and convenience.


Assuntos
Contaminação de Alimentos/prevenção & controle , Inocuidade dos Alimentos , Conhecimentos, Atitudes e Prática em Saúde , Alimentos Infantis/normas , Mães , Adolescente , Adulto , Bangladesh , Pré-Escolar , Feminino , Grupos Focais , Humanos , Lactente , Entrevistas como Assunto , Pessoa de Meia-Idade , População Rural , Fatores Socioeconômicos , Adulto Jovem
7.
J Appl Microbiol ; 116(4): 772-83, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24354999

RESUMO

AIMS: The aim of this study is to investigate the antibacterial activity of aluminium oxide nanoparticles (Al2 O3 NPs) against multidrug-resistant clinical isolates of Escherichia coli and their interaction with cell envelope biomolecules. METHODS AND RESULTS: Al2 O3 NPs were characterized by scanning electron microscope (SEM), high-resolution transmission electron microscope (HR-TEM) and X-ray diffraction (XRD) analyses. Antibacterial activity and interaction of Al2 O3 NPs with E. coli and its surface biomolecules were assessed by spectrophotometry, SEM, HR-TEM and attenuated total reflectance/Fourier transform infrared (ATR-FTIR). Of the 80 isolates tested, about 64 (80%) were found to be extended spectrum ß-lactamase (ESBL) positive and 16 (20%) were non-ESBL producers. Al2 O3 NPs at 1000 µg ml(-1) significantly inhibited the bacterial growth. SEM and HR-TEM analyses revealed the attachment of NPs to the surface of cell membrane and also their presence inside the cells due to formation of irregular-shaped pits and perforation on the surfaces of bacterial cells. The intracellular Al2 O3 NPs might have interacted with cellular biomolecules and caused adverse effects eventually triggering the cell death. ATR-FTIR studies suggested the interaction of lipopolysaccharide (LPS) and L-α-Phosphatidyl-ethanolamine (PE) with Al2 O3 NPs. Infrared (IR) spectral changes revealed that the LPS could bind to Al2 O3 NPs through hydrogen binding and ligand exchange. The Al2 O3 NPs-induced structural changes in phospholipids may lead to the loss of amphiphilic properties, destruction of the membrane and cell leaking. CONCLUSIONS: The penetration and accumulation of NPs inside the bacterial cell cause pit formation, perforation and disorganization and thus drastically disturb its proper function. The cell surface biomolecular changes revealed by ATR-FTIR spectra provide a better understanding of the cytotoxicity of Al2 O3 NPs. SIGNIFICANCE AND IMPACT OF THE STUDY: Al2 O3 NPs may serve as broad-spectrum bactericidal agents to control the emergent pathogens regardless of their drug-resistance mechanisms.


Assuntos
Óxido de Alumínio/farmacologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas , Antibacterianos/química , Membrana Celular/química , Parede Celular/ultraestrutura , Escherichia coli/enzimologia , Escherichia coli/ultraestrutura , Humanos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Fosfatidiletanolaminas/química , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Lactamases/biossíntese
8.
Mol Cell Biochem ; 384(1-2): 59-69, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23963993

RESUMO

Rotenone, a commonly used pesticide, is well documented to induce selective degeneration in dopaminergic neurons and motor dysfunction. Such rotenone-induced neurodegenration has been primarily suggested through mitochondria-mediated apoptosis and reactive oxygen species (ROS) generation. But the status of rotenone induced changes in liver, the major metabolic site is poorly investigated. Thus, the present investigation was aimed to study the oxidative stress-induced cytotoxicity and apoptotic cell death in human liver cells-HepG2 receiving experimental exposure of rotenone (12.5-250 µM) for 24 h. Rotenone depicted a dose-dependent cytotoxic response in HepG2 cells. These cytotoxic responses were in concurrence with the markers associated with oxidative stress such as an increase in ROS generation and lipid peroxidation as well as a decrease in the glutathione, catalase, and superoxide dismutase levels. The decrease in mitochondrial membrane potential also confirms the impaired mitochondrial activity. The events of cytotoxicity and oxidative stress were found to be associated with up-regulation in the expressions (mRNA and protein) of pro-apoptotic markers viz., p53, Bax, and caspase-3, and down-regulation of anti-apoptotic marker Bcl-2. The data obtain in this study indicate that rotenone-induced cytotoxicity in HepG2 cells via ROS-induced oxidative stress and mitochondria-mediated apoptosis involving p53, Bax/Bcl-2, and caspase-3.


Assuntos
Apoptose/efeitos dos fármacos , Inseticidas/farmacologia , Fígado/patologia , Estresse Oxidativo/efeitos dos fármacos , Rotenona/farmacologia , Caspase 3/biossíntese , Caspase 3/metabolismo , Catalase/metabolismo , Linhagem Celular Tumoral , Glutationa/metabolismo , Células Hep G2 , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/biossíntese , Proteína X Associada a bcl-2/metabolismo
9.
Hum Exp Toxicol ; 31(4): 336-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22241629

RESUMO

4-Hydroxynonenal (4-HNE) is one of the most reactive aldehydic by-products of lipid peroxidation. The role of 4-HNE in the etiology of various neurodegenerative disorders including cerebral ischemia/reperfusion, Alzheimer's disease, Parkinson's disease, etc. has been documented. We and others have reported that long-term toxic insults of 4-HNE triggers apoptotic signals and oxidative stress in various cells. However, the status of apoptosis following short-term exposure and underlying mechanisms has not been explored so far. We studied the apoptotic changes in PC12 cells receiving short-term exposure of 4-HNE. A significant dose-dependent induction in reactive oxygen species (ROS) and early response markers (c-Fos, c-Jun, and GAP-43) were observed in cells exposed to 4-HNE (10, 25, and 50 µM) for 1h. Following the exposure of PC12 cells to 4-HNE, the levels of protein and messenger RNA expressions of P(53), Bax, and caspase 3 were significantly upregulated, whereas the levels of Bcl(2) was downregulated. We could record the apoptotic signals and ROS generation in PC12 cells receiving 4-HNE exposure for such a short period of time. Induction in the expression and activity of caspase 3 has also indicated the mitochondrial mediation in the apoptosis induction.


Assuntos
Aldeídos/toxicidade , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Animais , Apoptose/genética , Biomarcadores/metabolismo , Western Blotting , Caspase 3/biossíntese , Caspase 3/metabolismo , Técnicas de Cultura de Células , Relação Dose-Resposta a Droga , Proteína GAP-43/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Células PC12 , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-jun/genética , RNA Mensageiro/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos
10.
Toxicol Int ; 18(2): 105-10, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21976814

RESUMO

Rotenone, a botanical insecticide is known to cause apoptosis in various cell types. Trans-resveratrol, a natural phytophenol present in red grapes and wine, is also well documented for its antioxidant, anti-inflammatory, anti-mutagenic, and anticarcinogenic activities. Therefore, the present investigations were carried out to assess the protective effect of trans-resveratrol against rotenone-induced cell death in human breast adenocarcinoma (MCF-7) cells. MCF-7 cells were exposed with various concentrations of rotenone for 24 h, and the loss in percent cell viability was evaluated by MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] and neutral red uptake (NRU) assays. A significant decrease in percent cell viability in MCF-7 cells was observed at 50 µM and above concentrations of rotenone, as compared to untreated control. Furthermore, various concentrations (5, 10, and 25 µM) of trans-resveratrol were used to see its protective role on cell viability in rotenone-induced cell death in MCF-7 cells. Pre- or post- treatment of trans-resveratrol for 24 h was given to the cells. The data exhibited a significant dose dependent increase in the percent cell viability under pre- and post-treatment conditions. However, post-treatment of trans-resveratrol for 24 h after rotenone exposure to the cells was relatively less effective. Overall, the results suggest that trans-resveratrol significantly protects MCF-7 cells from rotenone-induced cell death. This model can be used as an effective and economical alternative to animal models for screening the antioxidant activity of a variety of natural compounds/drugs.

11.
Mutagenesis ; 26(4): 533-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21430063

RESUMO

The intention of the present study was to answer the question whether the catalytic topoisomerase-II inhibitor, dexrazoxane, can be used as a modulator of teniposide-induced DNA damage and programmed cell death (apoptosis) in the bone marrow cells in vivo. The alkaline single cell gel electrophoresis, scoring of chromosomal aberrations, micronuclei and mitotic activity were undertaken in the current study as markers of DNA damage. Apoptosis was analysed by the occurrence of a hypodiploid DNA peak and caspase-3 activity. Oxidative stress marker such as intracellular reactive oxygen species production, lipid peroxidation, reduced and oxidised glutathione were assessed in bone marrow as a possible mechanism underlying this amelioration. Dexrazoxane was neither genotoxic nor apoptogenic in mice at the tested dose. Moreover, for the first time, it has been shown that dexrazoxane affords significant protection against teniposide-induced DNA damage and apoptosis in the bone marrow cells in vivo and effectively suppresses the apoptotic signalling triggered by teniposide. Teniposide induced marked biochemical alterations characteristic of oxidative stress including accumulation of intracellular reactive oxygen species, enhanced lipid peroxidation, accumulation of oxidised glutathione and reduction in the reduced glutathione level. Prior administration of dexrazoxane ahead of teniposide challenge ameliorated these biochemical alterations. It is thus concluded that pretreatment with dexrazoxane attenuates teniposide-induced oxidative stress and subsequent DNA damage and apoptosis in bone marrow cells. Based on our data presented, strategies can be developed to decrease the teniposide-induced DNA damage in normal cells using dexrazoxane. Therefore, dexrazoxane can be a good candidate to decrease the deleterious effects of teniposide in the bone marrow cells of cancer patients treated with teniposide.


Assuntos
Apoptose/efeitos dos fármacos , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Dano ao DNA , Razoxano/farmacologia , Teniposídeo/toxicidade , Animais , Células da Medula Óssea/enzimologia , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Cromossomos de Mamíferos/metabolismo , Quebras de DNA/efeitos dos fármacos , Citometria de Fluxo , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
12.
Hum Exp Toxicol ; 30(8): 860-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20801950

RESUMO

4-hydroxynonenal (4-HNE) and 6-hydroxydopamine (6-OHDA)-mediated damage in dopaminergic neurons is well documented. Protective potential of steroidal hormone (17ß-estradiol) has also been suggested. However, therapeutic potential of such promising hormone is hampered due to complex brain anatomy and physiology. Thus, the present investigations were studied to suggest the applicability of dopamine expressing PC12 cells as in vitro tool to screen the pharmacological potential of 17ß-estradiol against 4-HNE and 6-OHDA. MTT assay was conducted for cytotoxicity assessment of both 4-HNE (1 µM to 50 µM) and 6-OHDA (10(-4) to 10(-7) M). Non-cytotoxic concentrations, that is, 4-HNE (1 µM) and 6-OHDA (10(-6) M) were selected to study the synergetic/additive responses. PC12 cells were found to be more vulnerable towards co-exposure of individual exposure of 4-HNE and 6-OHDA, even at non-cytotoxic concentrations. Then, cells were subjected to pre-treatment (24 hours) of 17ß-estradiol (1 µM), followed by a permutation of combinations of both 4-HNE and 6-OHDA. Pretreatment of 17ß-estradiol was found to be significantly effective against the cytotoxic responses of 4-HNE and 6-OHDA, when the damage was at lower level. However, 17ß-estradiol was found to be ineffective against higher concentrations. Physiological-specific responses of PC12 cells against 4-HNE/6-OHDA and 17ß-estradiol suggest its applicability as first tier of screening tool.


Assuntos
Aldeídos/toxicidade , Estradiol/farmacologia , Fármacos Neuroprotetores/farmacologia , Oxidopamina/toxicidade , Animais , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Células PC12 , Ratos
13.
Toxicol In Vitro ; 24(6): 1592-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20600804

RESUMO

The role of 4-hydroxynonenal (4-HNE), a byproduct of membrane lipid peroxidation has been suggested in neurodegeneration. However, the underlying mechanisms are poorly understood. The investigations were carried out to study the preventive potential of trans-resveratrol against 4-HNE induced damage in PC12 cells. Trans-resveratrol, a natural compound obtained from grape skin and found in red wine, is reported to have wide pharmacological window. Cells pretreated with trans-resveratrol (5, 10 and 25 microM) for 24 h were exposed to 4-HNE (25 microM) for 2 h. Pre-treatment of trans-resveratrol was found to be significantly effective in countering the cytotoxic responses of 4-HNE. Significant reduction in reactive oxygen species generation, restoration of intracellular glutathione, and lipid peroxidation levels suggest the improved antioxidant defense system in the cells pretreated with trans-resveratrol. Further, 4-HNE induced alterations in the protein expression of mitochondria-mediated apoptosis markers (Bax, Bcl-2 and Caspase-3) were significantly restored by pre-treatment of trans-resveratrol suggesting the protective potential of trans-resveratrol in PC12 cells against 4-HNE induced oxidative damage. Together these data show the prophylactic potential of trans-resveratrol in oxidative stress mediated apoptotic neurodegeneration.


Assuntos
Aldeídos/toxicidade , Antioxidantes/farmacologia , Inibidores de Cisteína Proteinase/toxicidade , Citoproteção , Neurônios/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Antagonismo de Drogas , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Resveratrol
14.
Toxicol Ind Health ; 26(8): 533-42, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20634262

RESUMO

The investigations were aimed to study the possible association of dopamine DA-D(2) receptor in rotenone-induced cytotoxicity in PC12 cells, one among the most studied cell line in neurotoxicity studies. PC12 cells were subjected to receive an exposure of rotenone (10(-6) to 10(-4) M) for 24 and 48 hours. Cytotoxicity studies were carried out using standard end points including, (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT), lactate dehydrogenase (LDH) release and neutral red uptake (NRU). Cells were found to be vulnerable to rotenone in dose-dependent manner. In general, 10(-4) and 10(-5) M concentrations were found to be cytotoxic, whereas 10(-6) M and lower concentrations used have shown nonsignificant effect on cell viability. Further, studies were extended to study the rotenone-induced alterations in cellular glutathione (GSH) level and dopamine DA-D(2) receptor expression. Significant (p < 0.001) chronological depletion in GSH levels were recorded following rotenone exposure. Expression of dopamine DA-D(2) receptor was also found to be effected significantly (p < 0.001) at 24 hours of rotenone exposure (10(-4) and 10(-5)). However, no further depletion in the expression of dopamine DA-D(2) receptor could be recorded with extended exposure period, that is, 48 hours. Rotenone at 10(-6) M and lower concentrations was found to be ineffective in PC12 cells. Data suggest the vulnerability of PC12 cells against experimental exposure of rotenone, which possibly routed through dopamine DA-D(2) receptor and oxidative stress machinery.


Assuntos
Inseticidas/toxicidade , Receptores de Dopamina D2/metabolismo , Rotenona/toxicidade , Animais , Glutationa/metabolismo , L-Lactato Desidrogenase/metabolismo , Células PC12 , Ratos , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo , Testes de Toxicidade
15.
Oral Oncol ; 46(7): 553-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20538504

RESUMO

The concept of epithelial atrophy in oral submucous fibrosis (OSF) is based on the assumption of an ischemic epithelium consequent to poorly vascularized stroma, but the role of vascularity on the epithelial thickness in OSF is not clearly understood. This study aimed to investigate the immunohistochemical expression of CD34, for characterization and quantification of mucosal vasculature and its possible role in malignant transformation of atrophic epithelium in oral submucous fibrosis. After compilation of available data, the present study challenges the conventionally believed concept that epithelial atrophy in OSF is due to lack of perfusion, caused by decreased vascularity of subjacent connective tissue stroma. Characteristic pattern of juxtaepithelial loss of CD34 positive stromal cells and its role in malignant transformation in OSF deserves further attention.


Assuntos
Antígenos CD34/metabolismo , Mucosa Bucal/irrigação sanguínea , Neoplasias Bucais/irrigação sanguínea , Fibrose Oral Submucosa/patologia , Lesões Pré-Cancerosas/irrigação sanguínea , Adulto , Idoso , Atrofia , Estudos de Casos e Controles , Progressão da Doença , Epitélio , Feminino , Humanos , Imuno-Histoquímica , Masculino , Mucosa Bucal/patologia , Neoplasias Bucais/metabolismo , Fibrose Oral Submucosa/metabolismo , Lesões Pré-Cancerosas/patologia
16.
Lett Appl Microbiol ; 51(1): 54-60, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20477958

RESUMO

AIMS: Isolation, characterization and assessment of butachlor-degrading potential of bacterial strain JS-1 in soil. METHODS AND RESULTS: Butachlor-degrading bacteria were isolated using enrichment culture technique. The morphological, biochemical and genetic characteristics based on 16S rDNA sequence homology and phylogenetic analysis confirmed the isolate as Stenotrophomonas acidaminiphila strain JS-1. The strain JS-1 exhibited substantial growth in M9 mineral salt medium supplemented with 3.2 mmol l(-1) butachlor, as a sole source of carbon and energy. The HPLC analysis revealed almost complete disappearance of butachlor within 20 days in soil at a rate constant of 0.17 day(-1) and half-life (t((1/2))) of 4.0 days, following the first-order rate kinetics. The strain JS-1 in stationary phase of culture also produced 21.0 microg ml(-1) of growth hormone indole acetic acid (IAA) in the presence of 500 microg ml(-1) of tryptophan. The IAA production was stimulated at lower concentrations of butachlor, whereas higher concentrations above 0.8 mmol l(-1) were found inhibitory. CONCLUSIONS: The isolate JS-1 characterized as Stenotrophomonas acidaminiphila was capable of utilizing butachlor as sole source of carbon and energy. Besides being an efficient butachlor degrader, it substantially produces IAA. SIGNIFICANCE AND IMPACT OF THE STUDY: The bacterial strain JS-1 has a potential for butachlor remediation with a distinctive auxiliary attribute of plant growth stimulation.


Assuntos
Acetanilidas/metabolismo , Biotransformação , Microbiologia do Solo , Stenotrophomonas/isolamento & purificação , Stenotrophomonas/metabolismo , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Meios de Cultura/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Meia-Vida , Ácidos Indolacéticos/metabolismo , Dados de Sequência Molecular , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Fatores de Tempo , Triptofano/metabolismo
17.
Indian Pediatr ; 45(4): 319-21, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18451454

RESUMO

This study was done to determine the zinc levels in 30 children with celiac disease. Serum zinc level was estimated at inclusion and zinc supplementation was given for 3 months. Zinc levels were repeated at 3 and 6 months after inclusion. The serum zinc levels of newly diagnosed CD cases (0.64+/-0.34 microg/mL) versus controls (0.94+/-0.14 microg/mL) were significantly lower (95% CI -0.44 to -1.4), whereas in the old cases this difference was non-significant. The serum zinc level among severely malnourished and stunted celiac cases was also significantly lower irrespective of their treatment status. We conclude that serum zinc levels are low in newly diagnosed and severely malnourished children with celiac disease.


Assuntos
Doença Celíaca/sangue , Compostos de Zinco/uso terapêutico , Zinco/sangue , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Fatores de Risco , Zinco/deficiência , Compostos de Zinco/sangue
18.
FEMS Microbiol Lett ; 231(1): 13-7, 2004 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-14769460

RESUMO

The isolate NJ-101 obtained from agricultural soil was characterized and presumptively identified as Pseudomonas sp. The isolate exhibited efficient degradation of the insecticide carbofuran with a rate constant of 0.035 day(-1), following first-order rate kinetics. The ability of performing multifarious biological activities in tandem suggested the uniqueness of isolate NJ-101. The ability to produce hydrogen cyanide and siderophore stipulated its role in biological control. Furthermore, the growth inhibition of Fusarium sp. validated the antagonistic activity of NJ-101 against the common phytopathogens. Concurrent production of indole acetic acid, and solubilization of inorganic phosphate revealed its plant growth promoting potential. Thus, the innate capability of this novel isolate for parallel biodegradation, biocontrol and plant growth promotion has significance in management of the agro-environmental and phytopathological problems.


Assuntos
Carbofurano/metabolismo , Controle Biológico de Vetores , Pseudomonas/metabolismo , Biodegradação Ambiental , Doenças das Plantas/microbiologia , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , Pseudomonas/fisiologia , Microbiologia do Solo
19.
Lett Appl Microbiol ; 36(6): 349-53, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12753240

RESUMO

Phorate [O,O-diethyl-S-(ethylthio)methyl phosphoradiothioate] degrading bacteria were isolated from agricultural soil and characterized based on their morphological and biochemical characteristics. The selected isolates PS-1, PS-2 and PS-3 were presumptively identified as Rhizobium, Pseudomonas and Proteous species, respectively. The HPLC analysis of phorate in bioaugmented soil revealed its complete disappearance within 40 days. The degradation isotherms of the isolates PS-1, PS-2 and PS-3 suggested time-dependent disappearance of phorate following the first order rate kinetics at the corresponding rate constants of 0.04, 0.05 and 0.04 days-1. Besides, the isolates concurrently exhibited substantial phosphate solubilization, indole acetic acid, and siderophore production. The isolate PS-3 also showed anti-fungal activity against a phytopathogen Fusarium oxysporum. As a result of the multifarious biological properties, the isolates have been suggested to be important bioresource for efficient bioinoculant development.


Assuntos
Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/isolamento & purificação , Inseticidas/metabolismo , Forato/metabolismo , Microbiologia do Solo , Agricultura , Antibiose , Biodegradação Ambiental , Fusarium/crescimento & desenvolvimento , Bactérias Gram-Negativas/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Fosfatos/metabolismo , Proteus/classificação , Proteus/crescimento & desenvolvimento , Proteus/isolamento & purificação , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , Rhizobium/classificação , Rhizobium/isolamento & purificação , Sideróforos/metabolismo , Poluentes do Solo/metabolismo
20.
Indian J Environ Health ; 44(4): 282-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-13677065

RESUMO

The mechanical, physico-chemical characteristics of soil and the activity of indigenous microflora were studied in the agricultural soil steadily receiving petroleum refinery effluent at Mathura, U.P, India The data on the soil grain size and texture revealed that the soil in the test region was basically loam or silty loam. Physic-chemical analysis showed considerable variability in the soil pH, temperature, moisture content and water holding capacity (WHC). A substantially higher microbial activity was noticed at the test sites as evident from the total variable (10(5) to 10(9) CFU g-1 soil) bacterial population. In addition, a significant population of proteolytic and cellulolytic bacteria, rhizobium and actinomycetes was detected. Oligotrophs were isolated and characterized into four types (I-IV). A fraction of oligotrophic bacteria, particularly those belonging to type II and type IV exhibited appreciable in distilled water. Invariably higher microbial biomass ranging from 366 to 1604 mg CO2. 100 g-1 soil, clearly implied that the soil in the test region was very well nourished and the refinery waste was providing enough nitrites to support the growth of soil microflora.


Assuntos
Petróleo , Eliminação de Resíduos , Microbiologia do Solo , Agricultura , Conservação dos Recursos Naturais , Concentração de Íons de Hidrogênio , Resíduos Industriais , Temperatura , Água/análise
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