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1.
Huan Jing Ke Xue ; 37(3): 834-46, 2016 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-27337873

RESUMO

Indoor dust was an important and even a major route of human exposure to polybrominated diphenyl ethers (PBDEs). However, the vacuum dust concentrations were less correlated with indoor residents' serum concentrations of PBDEs, thus inadequat for either estimation of human exposure dose or research of deposition flux and its seasonal variations. Passive sampling of indoo dustfall could offset these shortages. A total of 49 indoor sampling sites including homes, offices, computer rooms and furniture factor were selected in Xiamen, China to collect the four season dustfall samples with glass plates (walled by clean aluminum foil). Deposition flux, concentrations, congener profiles, seasonal variations, and human exposure to PBDEs in the dustfall were studied The geometric means of the yearly round deposition flux of ∑ PBDEs (sum of 16 BDE congeners including BDE-209) in homes offices, computer rooms and furniture factory were 6.1, 3.0, 1.1 and 179.8 ng · (m² · d)⁻¹, respectively. The geometric mea deposition flux of ∑ PBDEs in homes was 2 times of that in offices, but the concentration of ∑ PBDEs in the dustfall from home (445.5 ng · g⁻¹) was only slightly higher than that of offices (384.0 ng · g⁻¹). The ∑ PBDEs deposition flux in homes, offices and computer rooms in Xiamen were at lower level compared with other cities around the world. The PBDEs deposition flux in furnitur factory was much higher than that in the ordinary indoor environment. Autumn was the season with highest deposition flux of ∑ PBDEs. Geometric means of BDE- 209's proportion of the ∑ PBDEs in dustfall in all seasons in the four types of indoo environment were above 80% . The deposition flux of PBDEs was correlated to the dustfall deposition flux in homes, offices and computer rooms, but not that in furniture factory. ∑15 PBDEs in homes and offices were significantly correlated with the age of computers, but not quantities of electrical and electronic products, furniture and interior decoration, etc. Indoor dust was a key route for human exposure to ∑ PBDEs, especially for higher brominated BDEs.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Éteres Difenil Halogenados/análise , Estações do Ano , China , Poeira/análise , Exposição Ambiental , Habitação , Humanos , Local de Trabalho
2.
Huan Jing Ke Xue ; 31(3): 579-85, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20358811

RESUMO

Indoor dry deposition of eight homes and offices in the urban area of Shanghai, China were sampled with clean glass plate during July to August of 2008 to study the indoor deposition flux and congener profiles of polybrominated diphenyl ethers (PBDEs). 16 PBDEs congeners which including BDE-17, -28, -71, 47, -66, -77, -100, -99, -85, -118, -154, -153, -138, -183, -190 and BDE-209 were measured by GC-MS with negative chemical ionization (NCI) in selected ion monitoring (SIM) mode. The particulate deposition flux of PBDEs in homes and offices were (10.9 +/- 8.2) and (14.2 +/- 11.9) ng x (m2 x d)(-1) respectively. Deca-BDE (BDE-209) was the major compound, accounting for 88.2% -99.2% of the quantified PBDEs. The particulate deposition flux in the offices [(3.1 +/- 2.0) mg x (m2 x d)(-1)] was relatively lower than that of homes, but the concentration of PBDEs in the particles [(3361.6 +/- 1987.4) ng x g(-1)] was significantly higher than that of homes [(1169.1 +/- 647.1) ng x g(-1)]. The concentration of PBDEs in the indoor dry deposition of Shanghai ranked in the middle level comparing with other cities around the world. The indoor deposition flux of PBDEs was mainly correlated with the flux of particle deposition and the usage of electrical and electronic products, but not the interior decoration and the amount of furniture.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Éteres Difenil Halogenados/análise , China , Cromatografia Gasosa-Espectrometria de Massas , Tamanho da Partícula
3.
Zhonghua Yi Xue Za Zhi ; 89(20): 1377-81, 2009 May 26.
Artigo em Chinês | MEDLINE | ID: mdl-19671325

RESUMO

OBJECTIVE: To investigate the expression of Cyclooxygenase (COX)-2 and the relationship between cox-2, mismatch repair gene (MMR) proteins and microsatellite instability (MSI) in HNPCC. METHODS: Twenty-eight cases of adenomas and 14 cases of carcinomas were collected from 33 HNPCC families patients by colonoscopy. Sporadic adenomas (n = 32) and carcinomas (n = 24) were used as a control group. The expressions of COX-2 and mismatch repair gene hMLH1, hMSH2, hMSH6 proteins were examined by immunohistochemistry. MS1 were analyzed by using PCR with BAT25, BAT26, D2S123, D5S346 and D17S250 loci. RESULTS: The COX-2 high-expression rates were 53.6% (15/28) and 42.9% (6/14) in HNPCC adenomas and carcinomas, and were 62.5% (20/32) and 91.7% (22/24) in sporadic adenomas and carcinomas. COX-2 expression was lower in HNPCC carcinomas than that of sporadic carcinomas (P < 0.05). MMR deficiency rate and positive rate of MSI-H were both 71.4% (10/14) respectively in HNPCC carcinomas. It was higher than that in sporadic colorectal carcinomas [both 12.5% (3/24)]. Eight (80.0%) COX-2 low-expression were observed in 10 HNPCC carcinomas with MMR-deficient system while 4 cox-2 high-expression cases were observed in 4 HNPCC carcinomas with MMR-proficient system. COX-2 expression was lower in HNPCC carcinomas and adenomas, sporadic carcinomas with MMR-deficient system than that of MMR-proficient (P < 0.05). The COX-2 low-expression rates were 80.0% (8/10), 66.7% (12/18) and 66.7% (2/3) in HNPCC adenomas, HNPCC carcinomas and sporadic carcinomas with MSI-H. Cox-2 expression was lower in HNPCC and sporadic carcinomas (adenocarcinomas) with MSI-H than that of MSS (P < 0.05). CONCLUSION: Compared with sporadic carcinomas, the COX-2 expression was lower in HNPCC carcinomas. There was negative correlation between COX-2 expression and MMR-deficient (MSI-H). The detection of COX-2, MMR protein and MSI is of important significance in further studying the pathogenesis and interventional therapy of colorectal neoplasms.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Ciclo-Oxigenase 2/metabolismo , Reparo de Erro de Pareamento de DNA , Instabilidade de Microssatélites , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/metabolismo , Proteínas Nucleares/metabolismo , Adulto Jovem
4.
Zhonghua Yi Xue Za Zhi ; 88(28): 1983-5, 2008 Jul 22.
Artigo em Chinês | MEDLINE | ID: mdl-19062740

RESUMO

OBJECTIVE: To investigate the mutations of the mismatch repair genes hMLH1 and hMSH2 in hereditary nonpolyposis colorectal cancer (HNPCC). METHODS: The DNA samples of 76 probands of HNPCC families underwent PCR amplification and sequencing on 35 exons in hMLH1 and hMSH2 genes. RESULTS: (1) The overall mutation rate of the hMLH1 and hMSH2 genes was 33% (25/76). (2) 22 mutations were found, 16 in the hMLH1 gene and 6 in the hMSH2 gene. (3) The spectrum of mutation type included frame shift, nonsense, splice site, and missense mutations. Missense mutation was the most common mutation type. CONCLUSION: The hMLH1 and hMSH2 mutations in Chinese HNPCC families show a wide spectrum. It seems that hMLH1 gene is involved more frequently than hMSH2 gene. A certain number of HNPCC families can be benefited from the genetic screening for mutation of the mismatch repair genes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteína 2 Homóloga a MutS/genética , Mutação , Proteínas Nucleares/genética , Grupo com Ancestrais do Continente Asiático/genética , China , Neoplasias Colorretais Hereditárias sem Polipose/etnologia , Análise Mutacional de DNA , Saúde da Família , Frequência do Gene , Humanos , Proteína 1 Homóloga a MutL , Mutação de Sentido Incorreto , Reação em Cadeia da Polimerase
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