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Breast Cancer Research and Treatment - Many patients seek breast reconstruction following mastectomy. Debate exists regarding the best reconstructive option. The authors evaluate outcomes comparing...  相似文献   
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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   
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OBJECTIVES: Detection of free fetal DNA (ffDNA) in maternal blood during pregnancy has given rise to the possibility of developing new noninvasive approaches for early prenatal diagnosis.On a large-scale study, two protocols of real-time polymerase chain reaction (PCR) were compared in order to establish which Y-specific locus, either multicopy DYS14 or single copy SRY sequence, was the most suitable for developing a test with high diagnostic efficiency for early fetal gender assessment. The second aim was to assess whether the combination of the two detection systems could increase the performance of the prenatal test. METHODS: We analyzed 145 plasma samples from healthy pregnant women between 11 and 12 weeks of singleton gestation. For each sample, fetal gender was determined by using both protocols (DYS14 and SRY) during the same real-time PCR run. RESULTS: The data obtained by the DYS14 and SRY assays showed an efficiency in fetal gender prediction of 97.9 and 80%, respectively. It is not advisable to combine the two protocols because this association does not help in further improvements in fetal gender prediction. CONCLUSIONS: DYS14 assay is the best approach for early fetal gender assessment because it is more sensitive, accurate, and efficient than the SRY assay.  相似文献   
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OBJECTIVE: This study aims to determine whether women with endometriosis have greater subclinical atherosclerosis than the general population. STUDY DESIGN: This case-control study included 66 women with endometriosis and 66 controls matched for age and body mass index. All subjects were >or=35 years old. Exclusion criteria were obesity, diabetes, hypertension, hyperlipidemia, renal or metabolic diseases. Before laparoscopy, all patients underwent a measurement of intima-media thickness (IMT) and distensibility coefficient (DC) on the common carotid artery. In addition, blood samples were taken to determine the levels of lipids, fibrinogen, C-reactive protein, homocysteine, fasting glycemia, antithrombin III, plasminogen, protein C, protein S, and activated protein C resistance. RESULTS: All the biochemical parameters evaluated had similar levels in the two study groups. IMT was similar in women with endometriosis and in controls both on left (p=0.330) and right (p=0.648) carotid artery. Similarly, no significant difference was observed in the DC between women with endometriosis and controls both on left (p=0.539) and right (p=0.178) carotid artery. No significant difference was observed in IMT and DC between women with mild and severe endometriosis. CONCLUSION: Women with endometriosis do not have more subclinical atherosclerosis than the general population.  相似文献   
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BACKGROUND: Although not frequent, major vascular injury (MVI) during laparoscopy in gynecologic surgery can cause a sharp increase in morbidity and mortality. CASE: During the abdominal entry stage of operative laparoscopy, perforation of the left common iliac artery occurred. Prolonged hiccups might have played a role. CONCLUSION: Entry into the abdominal cavity during laparoscopy should be performed with the safer, controlled technique. In spite of the fact that no surgical procedure or de- * vice is absolutely foolproof, the laparoscopic abdominal approach should be performed with the technique that maximally reduces the likelihood of MVI. Once a major vascular injury is recognized or suspected, immediate conversion to laparotomy should be considered.  相似文献   
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