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Synthetic amorphous silica (SAS) in its nanosized form is now used in food applications although the potential risks for human health have not been evaluated. In this study, genotoxicity and oxidative DNA damage of two pyrogenic (NM‐202 and 203) and two precipitated (NM‐200 and ‐201) nanosized SAS were investigated in vivo in rats following oral exposure. Male Sprague Dawley rats were exposed to 5, 10, or 20 mg/kg b.w./day for three days by gavage. DNA strand breaks and oxidative DNA damage were investigated in seven tissues (blood, bone marrow from femur, liver, spleen, kidney, duodenum, and colon) with the alkaline and the (Fpg)‐modified comet assays, respectively. Concomitantly, chromosomal damage was investigated in bone marrow and in colon with the micronucleus assay. Additionally, malondialdehyde (MDA), a lipid peroxidation marker, was measured in plasma. When required, a histopathological examination was also conducted. The results showed neither obvious DNA strand breaks nor oxidative damage with the comet assay, irrespective of the dose and the organ investigated. Similarly, no increases in chromosome damage in bone marrow or lipid peroxidation in plasma were detected. However, although the response was not dose‐dependent, a weak increase in the percentage of micronucleated cells was observed in the colon of rats treated with the two pyrogenic SAS at the lowest dose (5 mg/kg b.w./day). Additional data are required to confirm this result, considering in particular, the role of agglomeration/aggregation of SAS NMs in their uptake by intestinal cells. Environ. Mol. Mutagen. 56:218–227, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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The cellular infiltrate present in human diseased gingiva was analyzed in biopsies from 12 patients with gingivitis or periodontitis. The samples studied had been obtained in the course of surgery at inflammatory sites remaining after institution of periodontal treatment. Histological and immunological techniques were used to identify macrophages, B-cells, plasma-cells, T-cells and T cell subsets, as well as cells expressing class II HLA membrane antigens. T-cells appeared as the predominant population, but plasma-cells were also visualized in nearly all samples. Both OKT4+ and OKT8+ cells were seen in all cases, the latter being more numerous in periodontitis patients. Interdigitating-like cells were observed, positively labelled for class II antigens, as well as macrophages which were more numerous in periodontitis patients. These results suggest the participation of all components of the immune response in gingival disease, in a way resembling chronic recurrent inflammatory diseases.  相似文献   
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Between 1977 and 1987, 27 consecutive patients (16 men, 11 women, mean age 66 years, range 54 to 75 years) with ventricular septal rupture complicating acute myocardial infarction underwent surgical repair. The purpose of this retrospective study was to analyse the post-operative mortality factors from clinical, haemodynamic and operative data in all patients and also from coronary angiographic data in 23/27 patients whose haemodynamic status allowed this type of exploration. Seventeen patients (63 p. 100) died during the first post-operative month, 10 survived and were discharged. Factors that influenced the prognosis were: (1) inferiorly-located necrosis associated with a 75 p. 100 mortality rate (9 out of 12 patients), as opposed to 53 p. 100 (8 out of 15 patients) with anterior necrosis; (2) right ventricular dysfunction, observed in 83 p. 100 of patients with inferior necrosis and 53 p. 100 with anterior necrosis, which was responsible for 7 out of 9 deaths in the inferior necrosis subgroup and contributed to 3 out of 8 deaths in the anterior necrosis subgroup; this established a cause-effect relationship between right ventricular function and the overmortality of patients with inferior necrosis; (3) independently of the haemodynamic status, two- and three-vessel lesions (56 p. 100 of all lesions) which had an 84 p. 100 mortality rate as opposed to 40 p. 100 with one-vessel lesions; (4) the presence of a state of shock which was associated with a 78 p. 100 mortality rate as opposed to 55 p. 100 in patients without shock. We conclude that when permitted by the patient's haemodynamic status coronary angiography should be part of the pre-operative evaluation to assess the operative risk and guide the surgical procedure.  相似文献   
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The present study has been conducted to ascertain the level of allelic variation at codon 129 of the prion protein gene in France. Six French populations have been studied (Paris, Lille, Rennes, Chambéry, Grasse and Perpignan), totalling 1374 normal subjects. Mean heterozygosity in France is 46.5%, and the mean Met 129 allele (a high risk susceptibility factor for Creutzfeldt-Jakob disease) is 0.674. There is a genetic heterogeneity (chi(2)=38.44, p<0.001) between the six populations compared, and Met allele frequencies are inversely correlated with latitude (r=-0.93, p<0.01). Such an inverse correlation with latitude (r=-0.78, p=0.01) is also found when Met allele frequencies in France are compared to those already published in five other European countries and in Turkey. We hypothesise that high Met 129 frequencies populations may be at higher risk for Creutzfeldt-Jakob disease.  相似文献   
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BACKGROUND: Acne is a multifactorial disease exhibiting distinct clinical presentations. Among them, the catamenial type is a matter of concern for young women. Some oral contraceptives may help without, however, clearing the skin condition. AIM: The present open study aimed at evaluating the effect of overnight applications of a paste made of petrolatum,15% zinc oxide and 0.25% miconazole nitrate. METHOD: The split-face trial was conducted in 35 women. A non-medicated cream was used as control. Clinical evaluations and biometrological assessments on cyanoacrylate follicular biopsies were performed monthly for 3 months. Comedometry and the density in autofluorescent follicular casts were used as analytical parameters. In addition, the five most severe cases at inclusion were tested at the completion of the study for follicular bacterial viability using dual flow cytometry. RESULTS: Compared with baseline and to the control hemi-face, the medicated paste brought significant improvement of acne. The number of papules and their redness were reduced beginning with the first treatment phase. A reduction in the follicular fluorescence was yielded beginning with the second treatment phase. The ratios between injured and dead bacteria, on the one hand, and live bacteria, on the other hand were significantly increased at completion of the study. CONCLUSION: A miconazole paste applied for 1 week at the end of the ovarian cycle has a beneficial effect on catamenial acne.  相似文献   
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