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Otosclerosis is a condition characterized by an abnormal bone metabolism in the otic capsule, resulting in conductive and/or sensorineural hearing loss. Otosclerosis is a common disorder in which genes play an important role. Case-control association studies have implicated several genes in the abnormal bone metabolism associated with otosclerosis: COL1A1, TGFB1, BMP2, and BMP4. To investigate the association of these genes with otosclerosis in the Tunisian population, we examined nine single nucleotide polymorphisms (SNPs) in 159 unrelated otosclerosis patients and 155 unrelated controls. We found an association of rs11327935 in COL1A1 with otosclerosis that was shown to be sex specific. The coding polymorphism T263I in TGFB1 was also associated with otosclerosis in the Tunisian population. The effect sizes of both the associations were consistent with previous studies, as the same effect was found in all cases. The association of BMP2 and BMP4 was not significant. However, a trend towards association was found for the BMP4 gene that was consistent with earlier reports. In conclusion, this study replicates and strengthens the evidence for association between polymorphisms of COL1A1 and TGFB1 in the genetic aetiology of otosclerosis.  相似文献   
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Purpose

Australia has one of the highest incidences of colorectal cancer (CRC) in the world. In 2006, the federal government introduced a screening program consisting of a one-off fecal occult blood test offered to people turning 50, 55, or 65?years. We conducted a population-based study to estimate CRC screening practices existing outside the current program.

Methods

A total of 1887 unaffected subjects categorized “at or slightly above average risk” of CRC were selected from the Australasian Colorectal Cancer Family Registry. We calculated the proportions of participants that reported appropriate, under- and over-screening according to national guidelines. We performed a logistic regression analysis to evaluate associations between over-screening and a set of socio-demographic factors.

Results

Of 532 participants at average risk of CRC, eligible for screening, 4 (0.75?%) reported appropriate screening, 479 (90?%) reported never having been screened, 18 (3?%) reported some but less than appropriate screening, and 31 (6?%) reported over-screening. Of 412 participants aged 50?years or over, slightly above average risk of CRC, 1 participant (0.25?%) reported appropriate screening, 316 (77?%) reported no screening, and 11 (3?%) reported some but less than appropriate screening. Among participants under age 50?years, 2?% of those at average risk and 10?% of those slightly above average risk reported over-screening. Middle-aged people, those with a family history of CRC and those with a university degree, were more likely to be over-screened.

Conclusion

Overall, the level of CRC screening participation was low and the vast majority of screening tests undertaken were inappropriate in terms of timing, modality, or frequency.  相似文献   
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The concentrations of dichlorodiphenytrichloroethane and its metabolites (DDTs), hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), dieldrin, and 20 polychlorinated biphenyls (PCBs) were determined in 237 human breast milk samples collected from 12 locations in Tunisia. Gas chromatography with electron capture detector (GC-ECD) was used to identify and quantify residue levels on a lipid basis of organochlorine compounds (OCs). The predominant OCs in human breast milk were PCBs, p,p′-DDE, p,p′-DDT, HCHs, and HCB. Concentrations of DDTs in human breast milk from rural areas were significantly higher than those from urban locations (p<0.05). With regard to PCBs, we observed the predominance of mid-chlorinated congeners due to the presence of PCBs with high Kow such as PCB 153, 138, and 180. Positive correlations were found between concentrations of OCs in human breast milk and age of mothers and number of parities, suggesting the influence of such factors on OC burdens in lactating mothers. The comparison of daily intakes of PCBs, DDTs, HCHs, and HCB to infants through human breast milk with guidelines proposed by WHO and Health Canada shows that some individuals accumulated OCs in breast milk close to or higher than these guidelines.  相似文献   
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Allele frequencies for 15 STR autosomal loci of Identifiler kit (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) in the Moroccan population of Berber-speaking of Azrou, were assessed from a sample of 201 unrelated individuals. Markers D18S51, D2S1338, FGA and D21S11 present the highest power of discrimination (PD) values while D21S11 was the most polymorphic locus in the studied population. The phylogenetic tree established among worldwide populations, shows that Berber-speaking population of Azrou was so close to the Berber-speaking population of Asni but also to the Arab-speaking population of southern Morocco. Nevertheless, a significant distance was observed between populations of Azrou and Bouhria even they share the same dialect (Amazigh) and belong to the same geographical area (Morocco). The 15 STR loci studied appear to be highly discriminating, thus providing a powerful tool for forensic applications, paternity investigation, individual identification and anthropological studies.  相似文献   
66.
We conducted a systematic review and a meta-analysis of observational studies to identify and summarise the level of colorectal cancer (CRC) screening participation for people at increased risk due to family history of the disease. Medline, Cinhal, Embase and PsychInfo databases were comprehensively searched between January 1995 and May 2012 to identify relevant articles. To be included, studies had to report on screening for people who had at least one first-degree relative with CRC and no previous personal diagnosis of the disease. Pooled screening participation levels were calculated for each screening modality. Seventeen studies, accounting for a total of 13,269 subjects with a family history of CRC met the inclusion criteria. Seven studies, including a total of 6,901 subjects had a pooled faecal occult blood testing screening participation (at least once) of 25 % (95 % CI 12–38). Five studies including a total of 5,091 subjects had a pooled sigmoidoscopy-based screening participation (at least once) of 16 % (95 % CI 7–27). Seven studies including a total of 9,965 subjects had pooled participation colonoscopy-based screening (at least once) of 40 % (95 % CI 26–54). There was a significant level of screening heterogeneity between studies. This review identified a substantial underuse of CRC screening for people at increased risk of developing the disease. It highlights the potential opportunity that exists for increasing screening participation among this segment of the population and the need to adjust the current CRC screening policies towards that objective.  相似文献   
67.
Chronic exposure to potassium bromate (KBrO3), a toxic halogen existing widely in the environment, environment through contaminated drinking water, has become a global problem of public health. The present study investigates the protective role of vanillin against KBrO3 induced oxidative stress, distruption in inflammatory cytokines expression, DNA damage, and histopathological changes. Adult mice were exposed orally to KBrO3 (2g/L of drinking water) for 2 weeks The co‐administration of vanillin to the KBrO3‐treated mice significantly prevented the plasma transaminases increase in. Furthermore, it inhibited hepatic lipid peroxidation (malondialdehyde), advanced oxidation protein product (AOPP) and protein carbonyl (PCO) formation and attenuated the KBrO3‐mediated depletion of enzymatic and non enzymatic antioxidants catalase, superoxide dismutase, and glutathione peroxidase activities and glutathione level in the liver. In addition, vanillin markedly attenuated the expression levels of proinflammatory cytokines, including tumor necrosis factor‐α, interleukin‐1β, interleukin‐6, and COX2 and prevented KBrO3‐induced hepatic cell alteration and necrosis, as indicated by histopathological data. DNA damage, as assessed by the alkaline comet assay, was also found to be low in the co‐treated group. Thus, these findings show that vanillin acts as potent chemopreventive agent against KBrO3‐mediated liver oxidative stress and genotoxicity through its antioxidant properties. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1796–1807, 2016.  相似文献   
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