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The health risks associated with second hand smoke (SHS) are well-known. However, little is known about exposure to SHS in cars and risk of smoking uptake. This paper investigates the association between pre-adolescents reported exposure to smoking in cars and prevalence of early stage smoking activity. Data from Keeping Kids Smokefree baseline surveys of students were used to investigate smoking status and reported exposure to smoking in cars. Log binomial regression analyses were used to investigate if reported exposure to SHS in cars was associated with smoking prevalence. 83% of 5676 students invited took part. After controlling for all variables reported exposure to smoking in cars and homes were significantly associated with increased risk of initiated smoking (RR 1.87, 95% CI 1.43-2.44, and RR 1.5, 95% CI 1.13-1.97, respectively). Exposure to smoking in cars was substantially and significantly associated with risk of current smoking (RR 3.21, 95% CI 1.45-7.08). Early smoking uptake is associated with students' reported exposure to smoking in cars which confirms the importance of protecting children from SHS. Smoking in cars is under parental control and therefore modifiable. Moreover, children's reports of SHlS exposure offer a simple way of identifying families who can be targeted for tobacco control interventions.  相似文献   
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The genetic basis as well as mechanisms of development of germ cell tumors of the CNS are still unexplained. In the present article changes of Ecadherin (CDH1) and beta-catenin (CTNNB1) genes in two CNS germ cell tumors are reported. Both gene products are components of adherens junctions, but are also involved in the Wnt signaling pathway. A case of germinoma of the central nervous system and a case of spinal channel teratoma were tested for loss of heterozygosity (LOH) of E-cadherin gene by PCR amplification of tetranucleotide polymorphism (D16S752). Changes of beta-catenin were tested by heteroduplex method. Both germ cell tumors analyzed demonstrated LOH of the CDH1 gene. Analysis of exon 3 of the CTNNB1 gene showed additional band in the germinoma, suggesting that this sample harbors mutation in the beta-catenin gene. Immunostaining showed that LOHs in our samples were accompanied with the absence of E-cadherin protein. We also investigated E-cadherin expression in four other germinomas, of which three were negative and one was mildly positive. Our findings may contribute to better understanding of the genetic profile of germ cell tumors.  相似文献   
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The concentrations of mercury and 13 other trace metals in 104 canned fish samples purchased within the states of Georgia and Alabama (United States of America) were determined using the direct mercury analyzer (DMA) and the inductively coupled plasma-optical emission spectrometer (ICP-OES). The ranges obtained for the elements analyzed in mg/kg (wet weight) are as follows: Hg (0.02–0.74), Ag (0.0–0.20), As (0.0–1.72), Cd (0.0–0.05), Cr (0.0–0.30), Fe (0.01–88.4), Pb (0.0–0.03), Mn (0.01–2.55), Ni (0.0–0.78), Co (0.0–0.10), Cu (0.01–5.33), Sn (0.04–28.7), V (0.0–0.31) and Zn (0.14–97.8). Three tuna samples had Hg level above the European dietary limit of 0.5 mg Hg/kg. The mean Hg concentrations in the tuna (285 μg/kg) and sardine (107 μg/kg) brands were higher than the averages posted by the pink salmon (36.1 μg/kg), red salmon (32.8 μg/kg) and mackerel (36.4 μg/kg) brands. Two tuna samples and a sardine sample exceeded the Australian permissible limit of 1 μg/g inorganic arsenic (wet weight). Two samples (brand 15: herring) had zinc levels exceeding the Food and Agriculture Organization (FAO) recommended limit of 40 mg/kg and two pink salmons also exceeded the Brazilian regulatory limit of 0.1 mg Cr/kg. One tuna sample had a cadmium level slightly exceeding the Codex Committee on Food Additives and Contaminants draft guideline of 0.50 mg Cd/kg. However, the concentrations of lead, cadmium and copper were below the corresponding MAFF guidelines of 2.0, 1.0 and 30 mg/kg, respectively. Also, based on the United States Environmental Protection Agency (US EPA) health criteria for carcinogens, there are no health risks with respect to Pb, Cr, Cu and Zn concentrations in canned fishes analyzed. The result of the one-way analysis of variance (ANOVA) conducted on the data suggested that significant variations (P<0.05) existed in the concentrations of Hg, As, Co, Cr, Cu, Fe, Mn, Sn, V, and Zn across the various fish species and canned fish brands analyzed. The estimated weekly intakes of Hg, As, Cd, Pb, Sn, Fe, Cu and Zn for a 60 kg adult consuming 350 g of fish/week were below the respective provisional tolerable weekly intakes (PTWI) in μg/kg body weight for: Hg: 5; As: 15; Cd: 7; Pb: 25; Sn: 14000; Fe: 5600; Cu: 3500; and Zn: 7000.  相似文献   
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Background and aim. Metabolic syndrome is recognised as a potential risk factor for the development of hepatocellular carcinoma (HCC). The association between metabolic factors and hepatitis C (HCV)-related HCC has not yet been well clarified. This study was conducted to elucidate the role of metabolic factors in HCV-related HCC.Material and methods. We recruited 147 HCC patients and compared them with 147 matched CHC patients and 320 controls. The plasma levels of homeostasis model assessment-IR (HOMA-IR), adiponectin and lipids for all participants were assessed.Results. The HCC group showed significantly hig-her levels of insulin, glucose, HOMA-IR and adiponectin as well as lower levels of total cholesterol, HDL-C, LDL-C, and triglycerides compared with the matched CHC patients and controls. HOMA-IR did not correlate with pathologic features of HCC, whereas serum adiponectin levels correlated positively with the size of tumour nodules (P = 0.009). Based on stepwise logistic regression analysis, age (OR: 1.456, 95% CI: 1.0721.979, P < 0.01), HOMA-IR (OR: 2.50, 95% CI: 1.70-3.69, P = 0.001), and adiponectin (OR: 1.585, 95% CI: 1.2691.980, P = 0.001) were independently associated with HCC.Conclusions. Metabolic abnormalities are closely associated with the occurrence and development of HCV-related HCC. Patients with CHC and high serum adiponectin levels face a higher risk of developing liver cancer. Insulin resistance, as measured by HOMA-IR, is significantly associated with HCV-related HCC.  相似文献   
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The molecular mechanisms and candidate genes involved in development of meningiomas still need investigation and elucidation. In the present study 33 meningiomas were analyzed regarding genetic changes of tumor suppressor gene Adenomatous polyposis coli (APC), a component of the wnt signaling. Gene instability was tested by polymerase chain reaction/loss of heterozygosity (LOH) using Restriction Fragment Length Polymorphism (RFLP) method. RFLP was performed by two genetic markers, Rsa I in APC’s exon 11 and Msp I in its exon 15. The results of our analysis showed altogether 15 samples with LOH of the APC gene out of 32 heterozygous patients (47%). Seven patients had LOHs at both exons, while four LOHs were exclusive for exon 11 and four for exon 15. The changes were distributed according to pathohistological grade as follows: 46% of meningothelial meningioma showed LOH; 33% of fibrous; 75% of mixed (transitional); 75% of angiomatous, and one LOH was found in a single case of psammomatous meningioma. None of the LOHs were found in atypical and anaplastic cases. Immunostaining showed that samples with LOHs were accompanied with the absence of APC protein expression or presence of mutant APC proteins (χ2 = 13.81, df = 2, P < 0.001). We also showed that nuclear localization of β-catenin correlates to APC genetic changes (χ2 = 21.96, df = 2, P < 0.0001). The results of this investigation suggest that genetic changes of APC gene play a role in meningioma formation.  相似文献   
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AIM: To develop a reproducible model of significant left ventricular hypertrophy in order to study the role played by the tumor suppressor protein 53 (P53) in the mechanisms of cardiac hypertrophy, the cross-talk with the other factors and the connection between expression and activity of P53, cardiac myocyte apoptosis and heart hypertrophy; to discuss the problems and obstacles we faced. METHODS: Male Wistar rats were used in the experiments. Left ventricular hypertrophy was induced by banding the abdominal aorta. Three series of the experiment were performed differing in the place of banding and the size of constriction in order to find the most suitable model for our further research. RESULTS: Forty five days after banding the abdominal aorta just below the diaphragm the cardiac index increased by 30% in comparison with that in the controls. CONCLUSION: We have developed a reproducible model of significant left ventricular hypertrophy in rats. The main advantages of the model are: a) it is technically simple; b) it may be realised in any laboratory all over the world; c) it allows the most common lab animals (male Wistar rats) to be used for studies without having to be subjected to thoracotomy and hence requiring a long recovery period.  相似文献   
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