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PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight.  相似文献   
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Certain mammalian species are resistant to cancer, and a better understanding of how this cancer resistance arises could provide valuable insights for basic cancer research. Recent technological innovations in molecular biology have allowed the study of cancer‐resistant mammals, despite the fact that they are not the classical model animals, which are easily studied using genetic approaches. Naked mole‐rats (NMRs; Heterocephalus glaber) are the longest‐lived rodent, with a maximum lifespan of more than 37 years, and almost never show spontaneous carcinogenesis. NMRs are currently attracting much attention from aging and cancer researchers, and published studies on NMR have continued to increase over the past decade. Cancer development occurs via multiple steps and involves many biological processes. Recent research on the NMR as a model for cancer resistance suggests that they possess various unique carcinogenesis‐resistance mechanisms, including efficient DNA repair pathways, cell‐autonomous resistance to transformation, and dampened inflammatory response. Here, we summarize the molecular mechanisms of carcinogenesis resistance in NMR, which have been uncovered over the past two decades, and discuss future perspectives.  相似文献   
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Numerous solid tumors overexpress or have excessively activated insulin‐like growth factor receptor‐1 (IGF‐1R). We summarize preclinical studies and the first‐in‐human study of KW‐2450, an oral tyrosine kinase inhibitor with IGF‐1R and insulin receptor (IR) inhibitory activity. Preclinical activity of KW‐2450 was evaluated in various in vitro and in vivo models. It was then evaluated in a phase I clinical trial in 13 patients with advanced solid tumors (NCT00921336). In vitro, KW‐2450 inhibited human IGF‐1R and IR kinases (IC50 7.39 and 5.64 nmol/L, respectively) and the growth of various human malignant cell lines. KW‐2450 40 mg/kg showed modest growth inhibitory activity and inhibited IGF‐1‐induced signal transduction in the murine HT‐29/GFP colon carcinoma xenograft model. The maximum tolerated dose of KW‐2450 was 37.5 mg once daily continuously; dose‐limiting toxicity occurred in two of six patients at 50 mg/day (both grade 3 hyperglycemia) and in one of seven patients at 37.5 mg/day (grade 3 rash). Four of 10 evaluable patients showed stable disease. Single‐agent KW‐2450 was associated with modest antitumor activity in heavily pretreated patients with solid tumors and is being further investigated in combination therapy with lapatinib/letrozole in patients with human epidermal growth factor receptor 2‐postive metastatic breast cancer.  相似文献   
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Background  

Neuromyelitis optica (NMO) is a recurring inflammatory neurological disease characterized by severe optic neuritis and myelitis. The purpose of this study was to determine whether the retinal nerve fiber layer thickness (RNFLT) is correlated with the clinical presentations in patients with NMO and to determine the clinical factors that lead to poor visual outcomes.  相似文献   
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In vitro and in vivo antidermatophyte activities of NND-502, a new imidazole antimycotic agent, were compared with those of two existing antifungal agents, lanoconazole and terbinafine. NND-502 exhibited strong in vitro antifungal activity against Trichophyton spp.; its MIC was 1 to 4 times lower than that of lanoconazole or terbinafine. In an in vivo study with a guinea pig model of tinea pedis, 7-day topical treatment with a 0.5% solution of NND-502 (dissolved in polyethylene glycol 400) was more effective than that with a 0.5% solution of either lanoconazole or terbinafine for eradicating fungi from the infected feet. When the duration of treatment was shortened to 3 days, a topical 1% solution of NND-502 achieved a complete mycological cure, while topical 1% solutions of lanoconazole and terbinafine did not.  相似文献   
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ObjectivePrecursor lesions may be identified in fallopian tube tissue after risk-reducing salpingo-oophorectomy (RRSO) in patients with pathogenic variants of BRCA1/2. Serous tubal intraepithelial carcinoma (STIC) is considered a precursor of high-grade serous carcinoma, whereas the significance of the p53 signature remains unclear. In this study, we investigated the relationship between the p53 signature and the risk of ovarian cancer.MethodsWe analyzed the clinicopathological findings and conducted DNA sequencing for TP53 variants of p53 signatures and STIC lesions isolated using laser capture microdissection in 13 patients with pathogenic variants of BRCA1/2 who underwent RRSO and 17 control patients with the benign gynecologic disease.Results TP53 pathogenic variants were detected significantly higher in RRSO group than control (p<0.001). No difference in the frequency of p53 signatures were observed between groups (53.8% vs 29.4%; p=0.17). TP53 sequencing and next-generation sequencing analysis in a patient with STIC and occult cancer revealed 2 TP53 mutations causing different p53 staining for STICs and another TP53 mutation shared between STIC and occult cancer.ConclusionThe sequence analysis for TP53 revealed 2 types of p53 signatures, one with a risk of progression to STIC and ovarian cancer with pathological variants in TP53 and the other with a low risk of progression without pathological variants in TP53 as seen in control.  相似文献   
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