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101.
Hypermethylation of the DNA repair gene O(6)-methyl-guanine DNA methyltransferase (MGMT) has been linked to prolonged survival in glioblastoma patients treated with alkylating agents. It was aimed to analyze prospectively whether the MGMT status of malignant gliomas could be determined from small-sized stereotactic biopsies (maximum volume: 1 mm(3)). Special attention was directed towards the intratumoral distribution of the MGMT promoter methylation, the MGMT protein expression and potential correlations between both. Twenty-five adult patients were included (20 patients with primary World Health Organisation (WHO) Grade III or IV malignant gliomas, 5 patients with secondary malignant gliomas). About 2-4 biopsy specimens per tumor were collected from different sites within the tumor. Promoter methylation of the MGMT gene was assessed by methylation-specific PCR (MSP) and sodium bisulfite sequencing in each of the collected specimens (overall number of specimens: 69). Both methods were validated for application in small-sized tissue samples (1 mm(3)). The MGMT protein expression was analyzed by immunohistochemistry. The overall MGMT promoter methylation rate was 30% in the de novo group and 80% in the tumor progression group. The success rates of MSP and sequencing were 100% and 80%, respectively. Sequence analysis and MSP exhibited 100% concordant findings. No differences in MGMT promoter methylation were detected between the different samples of each individual tumor in 24 of 25 patients. One false negative result was obtained due to the contamination of the biopsy specimen by necrotic tissue. Tissue samples taken from different sites of each individual tumor (13 tumors investigated) exhibited equal or highly similar MGMT protein expression. No correlation between MGMT protein expression and MGMT promoter methylation was observed. The MGMT promoter methylation status of malignant gliomas can be reliably determined from small-sized stereotactic biopsies. The methylation profile, as defined by MSP and sodium bisulfite sequencing, constitutes a homogeneous marker throughout malignant gliomas. The lack of correlation between MGMT status and MGMT protein expression needs further evaluation.  相似文献   
102.
We performed segregation analyses of asthma and respiratory allergy based on data from 309 nuclear families comprising 1,053 individuals living in the town of Humboldt, Saskatchewan, in 1993, using the REGD program of the S.A.G.E. program package. For adults, information on asthma and history of respiratory allergy was provided by the subjects themselves, and for children by their parents. When asthma was considered as the trait in segregation analysis, models of no major effect, with or without familial effects, were rejected, but they were not rejected after adjusting for history of respiratory allergy. The major gene hypothesis was not rejected before adjusting for history of respiratory allergy. When respiratory allergy was analyzed as the trait, both major gene and multifactorial models fitted the data well, regardless of whether there was adjustment for asthma or not. Other covariates adjusted for in the segregation analyses were age, sex, number of household smokers, current smoking, number of household members, generation, and house type. The data suggest that a major gene related to respiratory allergy may explain the familial aggregation of asthma.  相似文献   
103.
Abstract— Ecto ATP-diphosphohydrolase (apyrase) activity of human endothelial cells following aspirin treatment has been studied in-vitro. It was shown by HPLC analysis of supernatant samples that pre-incubation of the cultures with aspirin resulted in a significantly increased turnover of supplemented ATP into its degradation products (ADP and AMP). Enhanced expression of ectoenzyme after aspirin treatment could be observed as demonstrated by immunofluorescence-staining with monoclonal anti-apyrase antibodies. This suggests enhancement of endothelial ATP-diphosphohydrolase activity induced by aspirin. The present data obtained in human vascular cells in-vitro are in line with results from previous animal studies in-vivo, suggesting a novel cyclo-oxygenase-independent antithrombotic activity of aspirin.  相似文献   
104.
105.
D Schnell  A Zaidi  G Reynolds 《Statistics in medicine》1989,8(3):343-52; discussion 363
Gonorrhea is the most frequently reported communicable disease in the United States. In response to rapidly rising rates in the late 1960s, the Public Health Service instituted a gonorrhea control programme. An important component of the programme is the screening of women for gonococcal infections. We use a time series intervention model to estimate the initial increase in reporting of cases in women associated with the control programme. From the middle 1970s to the middle 1980s, a regular seasonal pattern in the data is conspicuous. We use a second time series model to quantify the seasonal variation during this period and to construct forecasts.  相似文献   
106.
107.
BackgroundPrevious studies demonstrated the tolerability of palbociclib plus endocrine therapy (ET). This analysis evaluated safety based on more recent cutoff dates and a longer palbociclib treatment exposure.Patients and MethodsData were pooled from three randomized studies of patients with hormone receptor‐positive/human epidermal growth factor receptor 2‐negative (HR+/HER2−) advanced breast cancer (ABC), including postmenopausal women who had not received prior systemic treatment for advanced disease (PALOMA‐1/‐2) and pre‐ and postmenopausal women who had progressed on prior ET (PALOMA‐3).ResultsUpdated cutoff dates were December 21, 2017 (PALOMA‐1), May 31, 2017 (PALOMA‐2), and April 13, 2018 (PALOMA‐3). Total person‐years of treatment exposure were 1,421.6 with palbociclib plus ET (n = 872) and 528.4 with ET (n = 471). Any‐grade neutropenia and infections were more frequent with palbociclib plus ET (82.1% and 59.2%, respectively) than with ET (5.1% and 39.5%). The hazard ratios were 1.6 (p = .0995) for grade 3/4 infections, 1.8 (p = .4358) for grade 3/4 viral infections, 1.4 (p = .0001) for infections, and 30.8 (p < .0001) for neutropenia. Febrile neutropenia was reported in 1.4% of patients receiving palbociclib plus ET. Cumulative incidence of all‐grade hematologic adverse events in both arms peaked during the first year of treatment and plateaued over the 5 subsequent years. Interstitial lung disease was reported in 13 patients receiving palbociclib plus ET and 3 receiving ET.ConclusionThis 5‐year, long‐term analysis demonstrated that palbociclib plus ET has a consistent and stable safety profile and is a safe treatment for patients with HR+/HER2− ABC.Implications for PracticeSeveral treatments for patients with breast cancer are associated with long‐term or latent adverse events. This long‐term, 5‐year analysis demonstrated that palbociclib plus endocrine therapy has a consistent and stable safety profile without cumulative or delayed toxicities. These results further support palbociclib plus endocrine therapy as a safe and manageable treatment in clinical practice for patients with hormone receptor‐positive/human epidermal growth factor receptor 2‐negative advanced breast cancer.  相似文献   
108.
Left ventricular non-compaction (LV NC) is characterized by abnormal trabeculations that are mainly at the LV apex. Distinction between LV NC and non-specific dilated cardiomyopathies (DCMs) remains often challenging. We sought to find additive tools comparing the longitudinal strain characteristics of LVNC versus idiopathic DCM in a cohort of patients. 48 cases of LVNC (derivation cohort) were compared with 45 cases of DCM. Global and regional multi-layer (sub-endocardial, mid-wall, and sub-epicardial) LV longitudinal strain analysis was performed. Results were compared to define the best tool for distinguishing LVNC from DCM. A validation cohort (41 LVNC patients) was then used to assess the performance of the proposed diagnostic tools. In the derivation cohort, longitudinal deformation (strain) was greater in LVNC than in DCM patients. Longitudinal shortening was greater in the non-compacted segments than in the compacted ones. A mid-wall strain base-apex gradient had 88.4?% sensitivity and 66.7?% specificity in distinguishing LVNC from DCM (AUC?=?0.83; cut-off of ?23 or |0.23|%). In a multivariable model, the base-apex mid-wall gradient in an apical 4-chamber view was the only independent echocardiographic criteria (OR?=?0.76, CI 95?% [0.66; 0.90], p?=?0.0010) allowing the distinction between LVNC and DCM. In the validation cohort, the base-apex mid-wall gradient of strain had 88.4?% sensitivity, 85.7?% negative predictive values for the diagnosis of LVNC. Longitudinal strain, especially the base-apex longitudinal gradient of strain, appears as an additive valuable tool for distinguishing LVNC from DCM.  相似文献   
109.
Eastment  C; Denholm  E; Katsnelson  I; Arnold  E; Ts'o  PO 《Blood》1982,60(1):130-135
Experiments on long-term murine bone marrow cultures indicate that the production and maintenance of the hematopoietic stem cell is dependent on the establishment of an adherent monolayer and a secondary repopulation of the culture with fresh marrow. In contrast, we have found that bone marrow cultures derived from the Syrian hamster do not require a repopulation step and produce stem cells that proliferate and differentiate for more than 12 wk in the absence of an adherent layer. Stem cells were grown in Fisher's medium (pH 7.0-7.2) containing 20% horse serum in a fully humidified atmosphere of 5% CO2 in air at 37 degrees C. Cultures were fed twice weekly by removal of half of the medium and supernatant cells and replacement with an equal volume of fresh medium. No hormones or exogenous growth factors were required for the maintenance of myeloid cells, monocytes, and megakaryocytes in either the adherent or suspension cells cultures.  相似文献   
110.
In contrast to the murine system, long-term hamster bone marrow suspension cultures maintain proliferation of both pluripotent and committed stem cells in the absence of an adherent layer and without addition of exogenous factors, such as hydrocortisone. Addition of pokeweed-mitogen-stimulated hamster spleen conditioned medium (SCM) to these long-term suspension cultures produces an increase in the number of mixed colonies assayed in soft-agar, These mixed colonies, which contained four cell lineages--granulocytic, erythroid, megakaryocytic, and macrophage--could be generated from cells grown in suspension for over 6 mo. Addition of SCM also induces an initial rapid expansion of the myeloid compartment, and this expansion results in 70% of the cells being terminally differentiated granulocytes. In contrast, addition of SCM to hamster bone marrow cultures containing both adherent cells and hematopoietic stem cells produced no change in the number of mixed colonies generated in the culture. This system allows the in vitro study of the process of stem cell proliferation and differentiation and also provides a means to examine the relationship of adherent and supernatant bone marrow populations.  相似文献   
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