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41.
Abstract

Dysregulation of microRNAs (miRNAs) has a fundamental role in the initiation, development and progression of several human cancers, including breast cancer (BC), since strong evidence has shown that miRNAs can regulate the expression of oncogenes or tumor suppressor genes. A possible role of miRNAs in the diagnosis in BC has been demonstrated. As miRNAs has been found stable in biofluids, extracellular multiple miRNA profiles have been proposed as diagnostic tools, showing better diagnostic performance than individual miRNAs in BC. In this paper, based on the current literature, we present the role of microRNAs in the diagnosis and therapy monitoring of BC. Furthermore, we report new miRNA-based drugs that could be turned into promising therapy for BC, alone or in combination with conventional therapy. We also discuss how extracellular miRNAs could become new, easily accessible, affordable, non-invasive tools for BC patients.  相似文献   
42.
A Placebo-Controlled Crossover Trial of Nimodipine in Pediatric Migraine   总被引:1,自引:0,他引:1  
An 8-month, double-blind, placebo-controlled crossover trial was carried out on the use of nimodipine in migraine prophylaxis in 37 patients aged 7 to 18 years old. After a 4-week medication-free run-in period, 19 subjects (Group 1) received a placebo while 18 (Group 2) received nimodipine (10-20 mg t.i.d., according to body weight), for 12 weeks. After a 4-week wash-out period, the groups switched therapy for a further 12 weeks. 30 patients completed the trial and the number of dropouts was comparable in the 2 groups. The only side-effect during nimodipine treatment was mild abdominal discomfort (3 cases). The treatments were evaluated on the basis of frequency and duration of attacks. There was a significant reduction in both parameters during the first period of treatment. During the second period of treatment, nimodipine proved to have a significantly greater effect than the placebo with regard to frequency, whereas the response was similar with the placebo as regards duration of attacks. The latter parameter shows a significant decrease during the treatment periods, regardless of type of therapy.  相似文献   
43.
The properties of a mammary gland cancer stem cell   总被引:12,自引:1,他引:11  
The cancer stem cell hypothesis posits that tumors are derived from a single cancer-initiating cell with stem cell properties. The task of identifying and characterizing a single cancer-initiating cell with stem cell properties has proven technically difficult because of the scarcity of the cancer stem cells in the tissue of origin and the lack of specific markers for cancer stem cells. Here we show that a single LA7 cell derived from rat mammary adenocarcinoma has the following properties: the differentiation potential to generate all of the cell lineages of the mammary gland; the ability to generate branched duct-like structures that recapitulate morphologically and functionally the ductal-alveolar-like architecture of the mammary tree; and the capacity to initiate heterogeneous tumors in nonobese diabetic-SCID mice. In addition, we show that cultured cells derived from tumors generated by a single LA7 cell-injection have properties similar to LA7 cells, can generate all of the cell lineages of the mammary gland, and recapitulate the ductal-alveolar-like architecture of the mammary tree. The properties of self-renewal, extensive capacity for proliferation, multilineage differentiation potential, and single-cell tumor-initiation potential suggest that LA7 cells are cancer stem cells and can be used as a model system to study the dynamics of tumor formation at the single-cell level.  相似文献   
44.
OBJECTIVE: In patients with systemic lupus erythematosus (SLE), hydroxychloroquine prevents disease flares and damage accrual and facilitates the response to mycophenolate mofetil in those with renal involvement. A study was undertaken to determine whether hydroxychloroquine also exerts a protective effect on survival. METHODS: Patients with SLE from the multiethnic LUMINA (LUpus in MInorities: NAture vs nurture) cohort were studied. A case-control study was performed within the context of this cohort in which deceased patients (cases) were matched for disease duration (within 6 months) with alive patients (controls) in a proportion of 3:1. Survival was the outcome of interest. Propensity scores were derived by logistic regression to adjust for confounding by indication as patients with SLE with milder disease manifestations are more likely to be prescribed hydroxychloroquine. A conditional logistic regression model was used to estimate the risk of death and hydroxychloroquine use with and without the propensity score as the adjustment variable. RESULTS: There were 608 patients, of whom 61 had died (cases). Hydroxychloroquine had a protective effect on survival (OR 0.128 (95% CI 0.054 to 0.301 for hydroxychloroquine alone and OR 0.319 (95% CI 0.118 to 0.864) after adding the propensity score). As expected, the propensity score itself was also protective. CONCLUSIONS: Hydroxychloroquine, which overall is well tolerated by patients with SLE, has a protective effect on survival which is evident even after taking into consideration the factors associated with treatment decisions. This information is of importance to all clinicians involved in the care of patients with SLE.  相似文献   
45.
OBJECTIVE: To examine the risk factors for self-reported work disability in patients from the LUpus in MInorities: NAture vs. Nurture cohort with systemic lupus erythematosus (SLE). METHODS: Patients with SLE of Hispanic (Texas and Puerto Rico), African American and Caucasian ethnicity were studied. Work disability was defined by patients' self-report. Only patients known to be employed at the baseline visit were included. The probabilities of self-reporting work disability over time were examined by the Kaplan-Meier method; differences between ethnic groups were examined by the log-rank test. The relationship of baseline socioeconomic-demographic, clinical, behavioural and psychological features with work disability was examined by standard statistical tests. Variables with p相似文献   
46.
Porphyria cutanea tarda (PCT) is sometimes precipitated or aggravated by increased exposure to estrogen, estrogen-like compounds, or tamoxifen. We report the case of a 37-year-old white woman who developed sporadic PCT after she took oral contraceptives for 10 years. She was heterozygous for the common H63D mutation of the hemochromatosis-associated HFE gene. The PCT responded partially to the cessation of oral contraceptives and to phlebotomy therapy to maintain low iron stores, but only remitted after she received anastrozole therapy for management of adenocarcinoma of the breast at age 59 years. The pertinence of HFE mutations, anastrozole and tamoxifen treatment, and chemotherapy to the development and management of PCT in women with breast cancer is discussed.  相似文献   
47.
48.
The objective of this study was to analyze the usefulness of tumor necrosis factor-alpha and interleukin-6 cerebrospinal fluid concentrations for the differential diagnosis between bacterial and aseptic meningitis in children and in the prognostic evaluation. A cross-sectional study was performed on 35 children between 1 month and 12 years of age with suspected meningitis. Cytokines determination was performed by enzyme-linked immunosorbent assay technique. The Mann-Whitney test and Spearman's correlation coefficients were used for statistical analysis. Six children presented bacterial meningitis, 13 aseptic, and 16 had no meningitis. The tumor necrosis factor-alpha concentrations were significantly higher in the bacterial meningitis group as compared with the aseptic group (P = 0.001) and among groups with and without meningitis (P = 0.000). There was correlation between tumor necrosis factor-alpha and cerebrospinal fluid leukocytes (P = 0.019), protein (P = 0.000), and glucose (P = 0.038). There was no association between cytokines and complications of the meningitis. The tumor necrosis factor-alpha concentrations in the cerebrospinal fluid were useful markers for distinguishing bacterial from aseptic meningitis and were demonstrated to be useful in evaluating the intensity of the inflammatory process in the central nervous system.  相似文献   
49.
Spontaneous remission (SR) of acute myeloid leukemia (AML) represents a rare phenomenon and is usually of short duration although long‐term remissions are reported. Indeed, mechanisms underlying SR remain unclear, but it is suggested that immunactivation, e.g. caused by infections, plays an important role. Here we report on a patient who suffered from pneumonia and simultaneously experienced very late hematologic AML relapse seventeen years after allogeneic blood stem cell transplantation (allo‐BSCT). Surprisingly in parallel to recovery from pneumonia peripheral blood count which previously showed pancytopenia, had normalized and bone marrow (BM) aspiration revealed spontaneous remission of AML. To the best of our knowledge we here report on the latest AML relapse after allo‐BSCT experiencing SR.  相似文献   
50.
Several lines of evidence indicate that neutrophils act nonspecifically against tumor cells. The correlation between tumor-infiltrating neutrophils (TINs) and clinicopathological features remains unclear and deserves to be investigated. To analyze the prognostic influence of TINs in gastric carcinoma, the authors selected 273 patients with advanced gastric carcinoma who underwent gastrectomy at Cremona Hospital (Lombardia, Italy) between 1990 and 1995 and followed them for a period of 5 years. The number of TINs was assessed in a semiquantitative manner using the mean value of 20 nonoverlapping high-power fields (magnification, 400x; 0.08 mm(2)). The patients were divided into two groups: patients with a moderate or extensive amount of TINs (n = 76; >10 TINs per 20 high-power fields) and patients with a minor amount of TINs (n = 197; 相似文献   
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