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microRNAs (herein after miRNAs) represent a recently uncovered class of small and endogenous non-coding RNAs. miRNAs play a well conserved and crucial role in normal biological processes, such as cell differentiation, proliferation and apoptosis through a complicated gene regulation networking. The recent rise of interest in miRNAs in cancer research is ascribed to the breakthrough of their role in many pathological processes, including malignant transformation. miRNAs signatures have been clearly defined for certain types of cancer, with correlation to tumor aggressiveness, therapy response and patient outcome. Furthermore, the use of miRNAs as therapeutic targets for cancer is currently under investigation. The aim of this review is to focus on the role of miRNAs in breast cancer development and to summarize the evidence for their potential diagnostic and therapeutic applications in clinical practice.  相似文献   
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Introduction:In the adult human breast, hyperplastic enlarged lobular unit (HELU) and atypical ductal hyperplasia (ADH) are two common abnormalities that frequently coexist with ductal carcinoma in sit...  相似文献   
104.
PURPOSE: To better direct targeted therapies to the patients with tumors that express the target, there is an urgent need for blood-based assays that provide expression information on a consistent basis in real time with minimal patient discomfort. We aimed to use immunomagnetic-capture technology to isolate and analyze circulating tumor cells (CTC) from small volumes of peripheral blood of patients with advanced prostate cancer. EXPERIMENTAL DESIGN: Blood was collected from 63 patients with metastatic prostate cancer. CTCs were isolated by the Cell Search system, which uses antibodies to epithelial cell adhesion marker and immunomagnetic capture. CTCs were defined as nucleated cells positive for cytokeratins and negative for CD45. Captured cells were analyzed by immunofluorescence, Papanicolau staining, and fluorescence in situ hybridization. RESULTS: Most patients (65%) had 5 or more CTCs per 7.5 mL blood sample. Cell counts were consistent between laboratories (c = 0.99) and did not change significantly over 72 or 96 h of storage before processing (c = 0.99). Their identity as prostate cancer cells was confirmed by conventional cytologic analysis. Molecular profiling, including analysis of epidermal growth factor receptor (EGFR) expression, chromosome ploidy, and androgen receptor (AR) gene amplification, was possible for all prostate cancer patients with >or=5 CTCs. CONCLUSIONS: The analysis of cancer-related alterations at the DNA and protein level from CTCs is feasible in a hospital-based clinical laboratory. The alterations observed in EGFR and AR suggest that the methodology may have a role in clinical decision making.  相似文献   
105.
Saprochaete and Geotrichum spp. are rare emerging fungi causing invasive fungal diseases in immunosuppressed patients and scarce evidence is available for treatment decisions. Among 505 cases of rare IFD from the FungiScope? registry, we identified 23 cases of invasive infections caused by these fungi reported from 10 countries over a 12‐year period. All cases were adults and previous chemotherapy with associated neutropenia was the most common co‐morbidity. Fungaemia was confirmed in 14 (61%) cases and deep organ involvement included lungs, liver, spleen, central nervous system and kidneys. Fungi were S. capitata (n=14), S. clavata (n=5), G. candidum (n=2) and Geotrichum spp. (n=2). Susceptibility was tested in 16 (70%) isolates. All S. capitata and S. clavata isolates with the exception of one S. capitata (MIC 4 mg/L) isolate had MICs>32 mg/L for caspofungin. For micafungin and anidulafungin, MICs varied between 0.25 and >32 mg/L. One case was diagnosed postmortem, 22 patients received targeted treatment, with voriconazole as the most frequent first line drug. Overall mortality was 65% (n=15). Initial echinocandin treatment was associated with worse outcome at day 30 when compared to treatment with other antifungals (amphotericin B ± flucytosine, voriconazole, fluconazole and itraconazole) (P=.036). Echinocandins are not an option for these infections.  相似文献   
106.
Metastatic breast cancer remains an incurable disease and the median overall survival has not significantly improved over the past two decades. Aims of the present randomized phase II trial were to analyse activity and toxicity of chemotherapies with single agent or with combination regimens in previously treated patients with advanced breast cancer. Ninety-nine eligible patients were randomized to receive the following chemotherapies: Arm A – 30mg/m2 i.v. weekly; Arm B – leucovorin 100mg/m2 i.v. followed by 5-fluorouracil 370mg/m2 i.v. days 15, q 28days; Arm C – mitoxantrone 12mg/m2 i.v. only day 1+leucovorin 100mg/m2 i.v. followed by 5-fluorouracil 370mg/m2 i.v. days 13, q 28days. Patients characteristics are comparable in the three groups. The median number of chemotherapy courses administered was 7, 6 and 5 in arm A, B and C, respectively. Objective responses were 24%, 30% and 21% and the median duration of responses were 2, 2.5 and 5.5 months in the arm A, B and C, respectively. Median overall survivals were 9.5, 9 and 9 months in the three arms. No difference was noted comparing the survivals of responding or non responding patients. General toxicity was not mild, with 27.5% of patients experiencing WHO grade 3–4 toxicities.Our results are similar in the three groups of patients and comparable to those reported by other authors. Chemotherapy applied to patients with second or subsequent recurrence allow objective responses in a small percentage of patients. Moreover responders have a negligible prolongation of survival.  相似文献   
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Platinum electrodes modified with a cellulose acetate membrane or with poly(1,8-diaminonaphthalene) film were assembled and used for rapid amperometric detection of nitrites and nitrates in water by batch and flow injection analysis.Parameters such as the permeability of the electropolymerised films to nitrites and nitrates, interference effects and recovery studies of these kinds of sensors have been optimised to demonstrate the analytical suitability of the proposed method.Contrary to the standard colorimetric method, which is based on carcinogenic reagents, the amperometric detection of nitrites and nitrates is very simple and rapid and does not require any reagent for nitrite detection. Also, this method could be extended easily to the analysis of nitrites and nitrates in various types of samples such as food, soils, vegetables and fertilisers.  相似文献   
109.
BACKGROUND: Genetic studies have demonstrated that non-syndromic clefts of the lip, alveolus and palate have an heterogeneous genetic background, and that environmental factors contribute to the onset of this malformation. Therefore studies on different and homogeneous populations can be useful in detecting potentially related environmental and genetic factors. PURPOSE: The aim of the present study was to evaluate whether gender, folic acid intake, family history of diabetes and/or smoking during pregnancy were associated with a specific type of cleft in a group of patients affected by non-syndromic clefts, collected from Southern Italy. MATERIAL AND METHODS: Data from one hundred and twenty-six patients were evaluated retrospectively. Each cleft was described as composed by separate antomical entities such as lip, alveolus, primary and secondary palate. None had an isolated alveolar cleft and this was used as internal control. Pattern analysis was used to detect differences in the frequencies of any possible combination of 7 types of clefting stratified according to the studied variables. Data were analysed by comparing observed proportions. RESULTS: Isolated cleft palate as well as right-sided clefts of lip, alveolus and palate were more frequent in females (p = 0.0014 and 0.0281, respectively), while left sided clefts were more frequent in males (p = 0.0359). A lack of consumption of folic acid was associated with an higher incidence of clefts of the left lip (p = 0.018), while familial diabetes was associated more often with isolated cleft palate (p = 0.0014). CONCLUSIONS: Gender-related results were comparable with those found in Northern Italy and other countries. Environmentally related results disclosed specific subclasses of clefting associated with lack of folic acid consumption and familial diabetes.  相似文献   
110.
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