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1.
Artigo em Inglês | MEDLINE | ID: mdl-29234436

RESUMO

Chinese medicine has been used for Alzheimer's disease (AD) treatment for thousands of years with more effective and fewer side effects. Therefore, developing effective potential candidates from Chinese medicine against AD would be considered as critical and efficient therapy for AD treatment. This study was designed to evaluate the neuronal protective effect of fraction n-butanol (NB) of Radix Notoginseng on Aß25-35-induced PC12 cells, explore the effect of the tested fraction on spatial learning and memory, and characterize the impacts of fraction NB on antioxidant enzymes, Aß production, and APP and BACE1 expressions. The results revealed that fraction NB could promote proliferation of PC12 cells and protect and rescue PC12 cells from Aß25-35-induced cell death. Moreover, fraction NB could improve spatial learning and memory impairments of senescence-accelerated prone8 (SAMP8) mice and attenuate oxidative stress and reduce the production of Aß by inhibiting the expressions of APP and BACE1 in the brains of SAMP8 mice. The result of single dose acute toxicity assay showed that fraction NB had a mild toxicity in vivo. The pronounced actions against AD and in vivo low toxicity of fraction NB suggest that fraction NB may be a useful alternative to the current AD treatment.

2.
Environ Toxicol ; 32(2): 679-689, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27087047

RESUMO

Q10 is a powerful antioxidant often used in medical nutritional supplements for cancer treatment. This study determined whether Q10 could effectively prevent cardio-toxicity caused by doxorubicin treatment. Four week old SD rats were segregated into groups namely control, doxorubicin group (challenged with doxorubicin), Dox + Q10 group (with doxorubicin challenge and oral Q10 treatment), and Q10 group (with oral Q10 treatment). Doxorubicin groups received IP doxorubicin (2.5 mg/kg) every 3 days and Q10 groups received Q10 (10 mg/kg) every day. Three weeks of doxorubicin challenge caused significant reduction in heart weight, disarray in cardiomyocyte arrangement, elevation of collagen accumulation, enhancement of fibrosis and cell death associated proteins, and inhibition of survival proteins. However, Q10 effectively protected cardiomyocytes and ameliorated fibrosis and cell death induced by doxorubicin. Q10 is, therefore, evidently a potential drug to prevent heart damage caused by doxorubicin. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 679-689, 2017.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Cardiomiopatias/prevenção & controle , Cardiotônicos/farmacologia , Doxorrubicina/efeitos adversos , Ubiquinona/análogos & derivados , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cardiomiopatias/induzido quimicamente , Sobrevivência Celular/efeitos dos fármacos , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ubiquinona/farmacologia
3.
Huan Jing Ke Xue ; 35(8): 3060-5, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25338380

RESUMO

Dust intake is an important source of children's metal exposure. To explore the contamination level and health risk of toxic metals in kindergartens, surface dust samples were collected with self-made sampler in representative kindergartens in urban Beijing and concentrations of Pb, Hg, Cd, As were analyzed. It was found that Cd, Hg, Pb accumulated in indoor dust in different degrees with a significant seasonal variation. The geometric means of Pb, Cd, Hg, As concentrations were 63.12 microg x g(-1), 1.67 microg x g(-1), 0.06 microg x g(-1), 0.22 microg x g(-1) in summer and 117.40 microg x g(-1), 4.52 microg x g(-1), 0.95 microg x g(-1), 0.88 microg x g(-1) in winter, respectively. Geo-accumulation indexes calculated for each metal showed a severe contamination of Pb and Cd in indoor surface dusts. The results of exposure and health risk assessment of target substances displayed that the oral intake of dust metals was much higher than that of dermal pathways for children. However, no obvious carcinogenic and non-carcinogenic risks were found for all metals. The Pb, against other species, had the highest non-carcinogenic risk to children, Hazard Index of which was 0.12. Therefore, the health risk of Ph in indoor dust should raise the concern.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Monitoramento Ambiental , Metais Pesados/análise , Pré-Escolar , China , Exposição Ambiental , Humanos , Medição de Risco , Instituições Acadêmicas
4.
Biomed Environ Sci ; 25(4): 458-64, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23026526

RESUMO

OBJECTIVE: To obtain the exposure-response relationship for temperature and mortality, and assess the risk of heat-related premature death. METHODS: A statistical model was developed using a Poisson generalized linear regression model with Beijing mortality and temperature data from October 1st, 2006 to September 30th, 2008. We calculated the exposure-response relationship for temperature and mortality in the central city, and inner suburban and outer suburban regions. Based on this relationship, a health risk model was used to assess the risk of heat-related premature death in the summer (June to August) of 2009. RESULTS: The population in the outer suburbs had the highest temperature-related mortality risk. People in the central city had a mid-range risk, while people in the inner suburbs had the lowest risk. Risk assessment predicted that the number of heat-related premature deaths in the summer of 2009 was 1581. The city areas of Chaoyang and Haidian districts had the highest number of premature deaths. The number of premature deaths in the southern areas of Beijing (Fangshan, Fengtai, Daxing, and Tongzhou districts) was in the mid-range. CONCLUSION: Ambient temperature significantly affects human mortality in Beijing. People in the city and outer suburban area have a higher temperature-related mortality risk than people in the inner suburban area. This may be explained by a temperature-related vulnerability.


Assuntos
Mortalidade , Causas de Morte , China , Temperatura Alta , Modelos Estatísticos
5.
Huan Jing Ke Xue ; 30(11): 3159-66, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-20063723

RESUMO

Rain and atmospheric particle samples were collected in the rural area of Taian and Shenzhen in 2007, respectively. Rain sampling was carried out during the precipitation process and several samples were got from the beginning of one precipitation to the end. The chemical character changes during precipitation and the changes of concentration of particles before and after rain were studied in this research to understand the contribution of particles on the rain chemical character and the rain-out effect for particles. The volume-weighted mean pH of rainwater in Taian was 5.97 and the total concentration of ions was 1 187.96 microeq x L(-1). The mass concentration of PM10 in Taian was 131.76 microg/m3 and that of PM2.5 was 103.84 microg/m3. The volume-weighted mean pH of rainwater in Shenzhen was 4.72 and the total concentration of ions was 175.89 microeq x L(-1). The mass concentration of PM10 in Shenzhen was 56.66 microg/m3 and that of PM2.5 was 41.52 microg/m3. During precipitation process pH and ion concentration of rain decrease and it is shown the neutralizing effect happens. The difference between rainwater of Taian and Shenzhen is due to cloud water acidity, atmospheric particles character and atmospheric acid-basic gases concentration. The clean-up effect of Na+ and Ca2+ by rain is high and which of NH4+ and NO3- is low. The clean-up effect for mass concentration, ions concentration and element concentration of particles by rain are significant.


Assuntos
Chuva Ácida , Poluentes Atmosféricos/análise , Atmosfera/análise , Monitoramento Ambiental , Chuva/química , China , Tamanho da Partícula , Material Particulado/análise
6.
Huan Jing Ke Xue ; 30(12): 3441-7, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20187369

RESUMO

Secondary organic aerosols (SOA) is an important component of the atmospheric particle pollution, thus, determining the status and sources of SOA pollution is the premise of deeply understanding the occurrence, development law and the influence factors of the atmospheric particle pollution. Based on the pollution sources and meteorological data of Pearl River Delta region, the study used the two-dimensional model coupled with SOA module to stimulate the status and source of SOA pollution in regional scale. The results show: the generation of SOA presents obvious characteristics of photochemical reaction, and the high concentration appears at about 14:00; SOA concentration is high in some areas of Guangshou and Dongguan with large pollution source-emission, and it is also high in some areas of Zhongshan, Zhuhai and Jiangmen which are at downwind position of Guangzhou and Dongguan. Contribution ratios of several main pollution sources to SOA are: biogenic sources 72.6%, mobile sources 30.7%, point sources 12%, solvent and oil paint sources 12%, surface sources less than 5% respectively.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Modelos Teóricos , Compostos Orgânicos/análise , China , Simulação por Computador , Tamanho da Partícula , Processos Fotoquímicos , Rios
7.
J Environ Sci (China) ; 19(5): 572-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17915686

RESUMO

A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols (SOA) concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3-, NH4+, SO4(2-), and SOA were calculated in the fine particle size range (< 2.5 microm). The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign. Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly 03 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio.


Assuntos
Poluentes Atmosféricos/análise , Modelos Teóricos , Carbono/análise , Monóxido de Carbono/análise , China , Nitratos/análise , Óxidos de Nitrogênio/análise , Compostos Orgânicos/análise , Oxidantes Fotoquímicos/análise , Ozônio/análise , Material Particulado/análise , Compostos de Amônio Quaternário/análise , Reprodutibilidade dos Testes , Rios , Sulfatos/análise , Dióxido de Enxofre/análise
8.
Environ Sci Technol ; 41(4): 1405-12, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17593749

RESUMO

Bromine gas was evaluated for converting elemental mercury (Hg0) to oxidized mercury, a form that can readily be captured by the existing air pollution control device. The gas-phase oxidation rates of Hg0 by Br2 decreased with increasing temperatures. SO2, CO, HCl, and H2O had insignificant effect, while NO exhibited a reverse course of effect on the Hg0 oxidation: promotion at low NO concentrations and inhibition at high NO concentrations. A reaction mechanism involving the formation of van der Waals clusters is proposed to accountfor NO's reverse effect. The apparent gas-phase oxidation rate constant, obtained under conditions simulating a flue gas without flyash, was 3.61 x 10(-17) cm3 x molecule(-1) x s(-1) at 410 K corresponding to a 50% Hg0 oxidation using 52 ppm Br2 in a reaction time of 15 s. Flyash in flue gas significantly promoted the oxidation of Hg0 by Br2, and the unburned carbon component played a major role in the promotion primarily through the rapid adsorption of Br2 which effectively removed Hg0 from the gas phase. At a typical flue gas temperature, SO2 slightly inhibited the flyash-induced Hg0 removal. Conversely, NO slightly promoted the flyash induced Hg0 removal by Br2. Norit Darco-Hg-LH and Darco-Hg powder activated carbons, which have been demonstrated in field tests, were inferred for estimating the flyash induced Hg0 oxidation by Br2. Approximately 60% of Hg0 is estimated to be oxidized with the addition of 0.4 ppm of gaseous Br2 into full scale power plant flue gas.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Poluição do Ar/prevenção & controle , Bromo/química , Mercúrio/isolamento & purificação , Adsorção , Poluentes Atmosféricos/química , Carbono/química , Carvão Mineral , Cinza de Carvão , Mercúrio/química , Óxido Nítrico/química , Oxirredução , Material Particulado/química , Centrais Elétricas
9.
Sci Total Environ ; 367(1): 89-95, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16516274

RESUMO

This study examined the concentrations of carbon monoxide, carbon dioxide, TVOC, TSP, PM(10), PM(2.5), PM(1), benzene, toluene and xylene in passenger cars of the Beijing Ground Railway Transit System (Line No. 13). This system connects the northern suburb and downtown, and is equipped with air-conditioned passenger cars. In-train air quality monitoring was performed in both summer (July and August) and winter (December). To obtain representative data, the sampling design considered both rush and regular hours, urban and suburban areas, as well as the number of passengers. Meanwhile, questionnaires were distributed to the passengers. The monitoring results indicated that, overall, the air quality in the passenger cars was acceptable with a few exceptions, which is consistent with the passengers' perception. Concentrations of some air pollutants showed significant seasonal variations and had the significant difference between rush hour and regular hour. Furthermore, the in-train air quality was greatly influenced by the number of passengers. This paper describes the experimental design, and presents the preliminary results.


Assuntos
Poluentes Atmosféricos/análise , Ar/normas , Monitoramento Ambiental , Veículos Automotores/normas , Ar/análise , Ar Condicionado , China , Controle de Qualidade , Estações do Ano , Urbanização
10.
J Environ Sci (China) ; 17(1): 8-13, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15900749

RESUMO

Twenty-three kinds of typical plants in Xishuangbanna, the tropical area of southwestern China, were screened to estimate the emission rates of isoprene and monoterpenes by adopting bag-enclosure and curette sampling methods followed by a GC-FID analysis. It was found that the Ficus species were mainly emitting isoprene and most tropical vegetations were mainly releasing monoterpenes. The results also showed that the emissions of isoprene were affected by both temperature and PAR(Photosynthetic Active Radiation), while monoterpene emissions were mainly temperature-dependent.


Assuntos
Butadienos/metabolismo , Hemiterpenos/metabolismo , Monoterpenos/metabolismo , Pentanos/metabolismo , Plantas/metabolismo , China , Cromatografia Gasosa , Ionização de Chama , Estações do Ano , Temperatura , Clima Tropical
11.
Zhonghua Yan Ke Za Zhi ; 40(2): 78-81, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15059556

RESUMO

OBJECTIVE: To evaluate the effect of non-penetrating trabecular surgery (NPTS) with amniotic membrane implant in patients with juvenile glaucoma. METHODS: NPTS with amniotic membrane implant was performed on 32 eyes of 26 patients with juvenile glaucoma aged between 12 approximately 28 years. Intraocular pressure (IOP) was measured pre- and post-operatively by CT-60 non-contact tonometer, intraocular irritations and the bleb appearances were recorded, and the anterior chamber angle of post-operation was observed by gonioscopy. Follow-up was (8.3 +/- 4.2) months after surgery. RESULTS: IOP of post-operation was significantly decreased (15.7 +/- 3.7) mm Hg (1 mm Hg = 0.133 kPa; t = 4.82, P < 0.01) compared with that of pre-operation (28.6 +/- 7.3) mm Hg. The mean number of drug usage was significantly reduced to 0.8 (t = 128, P < 0.01) after surgery when compared with 3.2 before surgery. On the last visit, the IOP was

Assuntos
Âmnio/transplante , Glaucoma/cirurgia , Trabeculectomia/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Pressão Intraocular , Masculino , Acuidade Visual
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(7): 813-6, 2004 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15766078

RESUMO

The gas-phase reaction of a-pinene with ozone was tailed by LP-FTIR under 1.0 x 10(5) Pa and (296 +/- 3)K. The spectra were analyzed and a preliminary predication of the possible products was made. Then the mechanism of this reaction was extrapolated according to the IR data.


Assuntos
Monoterpenos/química , Ozônio/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Monoterpenos Bicíclicos , Gases/química
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