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81.
In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.  相似文献   
82.

Background

Mutations of the p53 oncosuppressor gene are amongst the most frequent aberration seen in human cancer. Some mutant (mt) p53 proteins are prone to loss of Zn(II) ion that is bound to the wild-type (wt) core, promoting protein aggregation and therefore unfolding. Misfolded p53 protein conformation impairs wtp53-DNA binding and transactivation activities, favouring tumor growth and resistance to antitumor therapies. Screening studies, devoted to identify small molecules that reactivate mtp53, represent therefore an attractive anti-cancer therapeutic strategy. Here we tested a novel fluorescent curcumin-based Zn(II)-complex (Zn-curc) to evaluate its effect on mtp53 reactivation in cancer cells.

Methods

P53 protein conformation was examined after Zn-curc treatment by immunoprecipitation and immunofluorescence assays, using conformation-specific antibodies. The mtp53 reactivation was evaluated by chromatin-immunoprecipitation (ChIP) and semi-quantitative RT-PCR analyses of wild-type p53 target genes. The intratumoral Zn-curc localization was evaluated by immunofluorescence analysis of glioblastoma tissues of an ortothopic mice model.

Results

The Zn-curc complex induced conformational change in p53-R175H and -R273H mutant proteins, two of the most common p53 mutations. Zn-curc treatment restored wtp53-DNA binding and transactivation functions and induced apoptotic cell death. In vivo studies showed that the Zn-curc complex reached glioblastoma tissues of an ortothopic mice model, highlighting its ability to crossed the blood-tumor barrier.

Conclusions

Our results demonstrate that Zn-curc complex may reactivate specific mtp53 proteins and that may cross the blood-tumor barrier, becoming a promising compound for the development of drugs to halt tumor growth.  相似文献   
83.
Reducing mortality, especially premature death, is a major goal of the fight against cancer. In this study, we have analyzed trends in malignant melanoma (MM) mortality in the European Community (EC) as a whole and for each country. The data (obtained from the World Health Organization data bank) have been analyzed for the period 1970-90, by age groups (20-44, 45-64, 65-74, 75+ years). Trends are presented as percentage change of mortality rate for each three-year period in comparison with the rate in the first one (1970-72). The mortality from MM in the EC as a whole increased for both genders (men, +89.2 percent; women, +72.6 percent), with statistically significant trends in all age classes. Northern countries experienced mortality changes about 30 to 50 percent less than the EC average increase. Greater changes were seen in southern European countries, in which recent standardized rates are near to those observed in northern European populations. Among Mediterranean people, the highest increase (more than fourfold) was observed in Spain. The significant increase found for the younger age class makes unlikely the risk of misclassification with other skin cancers. No future decrease in MM mortality in the EC is indicated from these data.  相似文献   
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OBJECTIVE: We sought to determine the significance of lymphatic vessel density (LVD) in pre-malignant lesions and carcinomas of the uterine cervix and to evaluate the prognostic value of lymphatic invasion and D2-40 positivity in tumor cells in the three histological types of invasive lesions. The correlation of LVD, lymphatic invasion and D2-40 positivity in tumor cells with EGFR and COX-2 expressions was also evaluated. METHODS: We studied 50 cervicitis, 50 low-grade squamous intraepithelial lesions (LSIL) (CIN1), 51 high-grade squamous intraepithelial lesions (HSIL) (CIN2/CIN3), 49 invasive squamous cells carcinomas (SCC), 43 adenocarcinomas (AC) and 30 adenosquamous cells carcinomas (ASC). The immunoreaction assay was performed using the monoclonal antibody D2-40. RESULTS: Significant differences in LVD were found among all categories of pre-invasive and invasive lesions (p=0.001 and p<0.001, respectively). LVD in invasive lesions was significantly greater than in pre-invasive lesions (p<0.001) and no significant association was found between LVD in invasive lesions and both lymph node invasion and/or metastasis. D2-40 positivity in tumor cells was associated with a better prognosis in ASC cases. EGFR and COX-2 expressions in invasive lesions were not associated with LVD; however, they correlated with both lymphatic invasion and D2-40 positivity in tumor cells. CONCLUSIONS: Lymphatic neovascularization begins early in intraepithelial lesions and continues to increase towards malignancy. Both lymphatic invasion and decrease in D2-40 expression in tumor cells appear to have a prognostic value.  相似文献   
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OBJECTIVE: The aim of the present study was to compare the distribution of G1691A, G20210A and C677T mutations in pre-eclamptic Brazilian women and in matched control women with an uncomplicated normal pregnancy. STUDY DESIGN: these mutations were investigated by PCR-RFLP in 83 normal pregnancies (control group) and in 30 pre-eclamptic pregnant women (severe form). RESULTS: G1691A mutation was detected neither in the control group nor in pre-eclamsia women. G20210A mutation was detected in heterozygosis in 3 (3.61%) control subjects, but not in pre-eclampsia group. C677T mutation was detected in homozygosis in 6 (7.23%) control subjects and 2 (6.67%) pre-eclamptic women and in heterozygosis in 31 (37.3%) control subjects and 12 (40%) pre-eclamptic women. Differences in the mutation frequencies detected in the two groups were not statistically significant. CONCLUSION: No correlation was observed between pre-eclampsia and presence of G1691A, G20210A and C677T mutations in Brazilian women.  相似文献   
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