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1.
Monitoring left ventricular dilation in mice with PET.   总被引:3,自引:0,他引:3  
Molecular imaging by small-animal PET is an important noninvasive means to phenotype transgenic mouse models in vivo. When investigating pathologies of the left ventricular (LV) myocardium, the serial assessment of LV volumes is important. By this, the presence of LV dilation as a sign of developing heart failure can be detected. Whereas PET is usually used to derive biochemical and molecular information, functional parameters such as ventricular volumes are generally measured using echocardiography or MRI. In this study, a novel method to monitor LV dilation in mice with PET is presented and evaluated using cardiac MRI. METHODS: A semiautomatic 3-dimensional algorithm was used to delineate the LV myocardial wall on static PET images depicting myocardial glucose metabolism ((18)F-FDG PET) for 20 mice: 10 wild-type and 10 genetically modified littermates designed to develop a dilative cardiomyopathy phenotype (cardiomyocyte-specific knockout of survivin). The volume enclosed by the 3-dimensional midmyocardial contour was calculated as a measure for LV volume for each mouse. Data were compared with ventricular volumes measured by MRI in the same animals. RESULTS: LV volumes obtained by PET and MRI correlated well (R = 0.89) for hearts with small and large left ventricles. In accordance with the hypothesis, the LV volumes were increased significantly for transgenic mice examined at an older age compared with those examined at a younger age (MRI: 160.5 +/- 25.7 microL vs. 114.7 +/- 15.2 microL [P = 0.012]; PET: 129.3 +/- 15.3 microL vs. 73.8 +/- 15.0 microL [P < 0.001], all values shown as mean +/- SD; for MRI, mean of end-diastolic and end-systolic volumes are given), whereas they did not for their wild-type littermates (MRI: 106.2 +/- 12.3 microL vs. 94.7 +/- 14.6 microL [P = 0.214]; PET: 82.6 +/- 20.9 microL vs. 65.0 +/- 16.9 microL [P = 0.185]). CONCLUSION: Evaluation and quantitation of LV dilation in both control and cardiomyopathic mice can be reliably and serially performed using small-animal PET and (18)F-FDG, yielding useful functional information in addition to metabolic data.  相似文献   
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This study was sought to evaluate the relationship between Her-2 protein expression, cellular localization, gene amplification, and other clinicopathologic parameters in colorectal carcinomas. Her-2 protein expression and gene amplification were assessed in paraffin sections from 106 primary colorectal adenocarcinoma cases using immunohistochemistry and fluorescence in situ hybridization. Both membranous and cytoplasmic immunostaining was evaluated. The results were correlated with each other and with tumor grade, stage, and overall survival. Membranous and cytoplasmic protein expression was identified in 6 (5.6%) and 13 (12.26%) cases, respectively. Gene amplification was detected in 4 (3.7%) cases. There was a high concordance between membranous protein expression and gene amplification (kappa=0.791). No apparent association with any of the clinicopathologic parameters was identified. Membranous Her-2 protein expression and gene amplification are encountered in a small subset of colorectal carcinomas and are highly concordant events. Cytoplasmic protein expression might be either artifactual or it might represent a cross-reacting protein or a precursor form of the mature protein.  相似文献   
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Rationale: The atypical neuroleptic risperidone, in addition to its dopamine receptor blocking activity, has a high affinity for serotonergic receptors. Since both dopaminergic and serotonergic neuronal activities participate in regulation of the pituitary – gonadal axis (PGA), it is expected that a switch from treatment with haloperidol to treatment with risperidone should influence plasma levels of PGA hormones. Objective: To study the effects of a drug with dopamine and serotonin receptor blocking activity on PGA hormones in patients who were on treatment with a dopamine receptor blocker. Methods: Plasma levels of testosterone, luteinizing harmone (LH) and follicle stimulating harmone (FSH), as well as prolactin and cortisol, were measured in 16 male schizophrenic patients during treatment with haloperidol (mean dose 23.3 mg daily, SD = 16.9) and 6 weeks later after switching to treatment with risperidone (mean dose 11.8 mg daily, SD = 2.9). Psychopathology was assessed by BPRS. Results: After switching to risperidone, total BPRS score and the scores in its subscales for positive, negative, and general symptoms were all significantly reduced in the order of 35–45%. Prolactin levels were significantly increased from 39.5 ± 22.3 to 58.9 ± 28.5 ng/ml (F = 4.61, P = 0.04), while cortisol, testosterone, LH, and FSH remained unchanged. No significant correlations between prolactin increases and reduction in BPRS or in its subscale scores were found. Conclusions: The results show that blocking of both dopamine and serotonin receptors does not influence the pituitary – gonadal axis but considerably increases prolactin release. Received: 29 June 1998/Final version: 23 October 1998  相似文献   
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PURPOSE: To evaluate the efficacy and toxicity of gemcitabine (GEM) combined with capecitabine (CAP) in untreated patients with inoperable or metastatic pancreatic cancer. PATIENTS AND METHODS: Fifty-three patients with pancreatic cancer (85% stage IV) were enrolled. Patients were treated with GEM 1000 mg/m2 on days 1 and 8 and CAP 1300 mg/m2 per day PO (per os), divided into two equal doses on days 1-14, in 21-day cycles. RESULTS: In an-intention-to-treat analysis, 10 (18.9%) objective partial responses were achieved (95% confidence interval 8.33% to 29.4%). Twenty-two (42%) patients had stable disease and 15 (28%) had progressive disease. The median response time was 3 months (range 1.5-7.0) and the median time to tumor progression was 6.5 months (range 3.5-15.5). Median overall survival time was 8 months (range 1.0-15.5) and 1-year survival was 34.8%. Pain improvement during treatment was observed in 23 of 43 (53%) patients, and eight of 18 (44%) patients who had been receiving opioids discontinued their use. Weight gain was observed in 12 of 33 (36%) patients. Grade 3 anemia occurred in five (9%) patients and grade 3-4 thrombocytopenia occurred in three (6%). Grade 3-4 neutropenia occurred in 13 (25%) and five (9%) patients, respectively, and two (4%) developed febrile neutropenia. Non-hematological toxicity was mild. CONCLUSION: In patients with pancreatic cancer, the combination of GEM with CAP is an active and well tolerated regimen that merits further evaluation in prospective randomized studies.  相似文献   
6.
BACKGROUND: To investigate the incidence of direct hematogenous spread of cancer cells in patients with early-stage breast cancer by studying the presence of occult tumor cytokeratin-19 (CK-19) mRNA(+) cells in the peripheral blood in relation to the status of sentinel (SLNs) and (ALNs) axillary lymph nodes. PATIENTS AND METHODS: SLNs and ALNs from 111 patients with operable stage I-II breast adenocarcinoma were evaluated for the presence of tumor cells by hematoxylin-eosin (H&E) staining and, if negative, by immunohistochemistry (IHC) using an anti-CK-19 antibody. Peripheral blood was also analyzed for the presence of CK-19 mRNA(+) cells by nested RT-PCR, before the initiation of adjuvant treatment and in CK-19 mRNA(+) patients following the completion of adjuvant chemotherapy and hormonal treatment. RESULTS: After both H&E staining and IHC analysis, 29 (26%) patients were ALN negative (N0). In 78 (70%) patients H&E staining and in four (3.6%) IHC analysis revealed tumors cells, and these patients were considered as ALN positive (N+). Peripheral blood CK-19 mRNA(+) cells were detected in nine (31%) out of 29 N0 and in 31 (38%) out of 82 N + patients (P=0.5) before any adjuvant treatment. Adjuvant chemotherapy and hormone treatment resulted in the disappearance of the CK-19 mRNA(+) cells in all N0 patients and in 15 out of 31 N + patients. After a median follow-up of 40 months, all the N0 CK-19 mRNA(+) patients were relapse-free whereas four (13%) N + CK-19 mRNA(+) patients had relapsed. CONCLUSIONS: Direct hematogenous dissemination of occult tumor cells may occur in a substantial proportion of patients with early-stage breast cancer. The prognostic implication of the detection of these cells requires long follow-up periods and further studies.  相似文献   
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Rationale, aims and objectives Developing homogenous low back pain (LBP) classification groups is recommended for enhancing clinical outcomes. However, an important step towards the development of specific subgroups is the selection and consensus agreement among health professionals on the discriminatory clinical items (sings and symptoms) that should be included in the classification process. Thus, this study's objective was to develop a list of clinical features for the assessment of LBP by health care providers within Greece, which are believed to be discriminatory in identifying LBP subgroups. Methods A random sample stratified by geographical region and work status of 150 Greek physiotherapists (PTs) participated in a two‐round Delphi study. PTs were asked to obtain consensus and hierarchy, the most important items out of a list of evaluating/diagnostic features believed to be discriminatory for LBP patients. These items included 80 clinical features and were generated in by PTs and doctors previous work. Results Second‐round questionnaires were returned by 112 PTs (74.6% response rate). A total of 66 clinical features were rated as important discriminatory items in LBP assessment. Clinical items included characteristics of present symptoms and the history's condition, general medical history, information regarding patient function, patients' attitudes regarding movement, diagnosis, expectations, fear‐avoidance beliefs as well as aspects of a physical examination including observation, active and passive movements, neurological and muscular examination. Conclusions This is the first study identifying important clinical items for LBP patients in Greece. It may be that these features are ‘discriminatory’ for different LBP subsets; however, further research is needed.  相似文献   
10.
Vascular smooth muscle and glomerular mesangial cells in culture express a biochemical pathway that methylates 2-hydroxyestradiol (17beta-estradiol metabolite) to produce 2-methoxyestradiol, a cell growth inhibitor that may mediate the cardiorenal protective effects of 17beta-estradiol. Whether this pathway exists in intact organ systems is currently unclear. Accordingly, the purpose of the present investigation was to characterize the methylation of 2-hydroxestradiol in intact organs from both male and female rats. No significant differences were detected in the ability of male and female tissues to methylate 2-hydroxyestradiol. In isolated hearts, kidneys, and mesenteries perfused with Tyrode's solution, Km values for 2-hydroxyestradiol methylation were 0.175+/-0.021, 0.387+/-0.054, and 0.495+/-0.089 micromol/L, respectively, and Vmax values were 21.0+/-1.58, 24.9+/-1.49, and 1.01+/-0.148 pmol 2-methoxyestradiol x min(-1) x ml(-1) per gram, respectively. The catalytic efficiency (Vmax/Km) was greatest in the heart compared with the kidney and mesentery (132+/-14.3, 78.4+/-15.1, and 2.30+/-0.263 pmol 2-methoxyestradiol x min(-1) x mL(-1) x micromol/L(-1) per gram, respectively). In the kidney, the catechol-O-methyltransferase inhibitor quercetin and norepinephrine (10 micromol/L) reduced methylation of 2-hydroxyestradiol by approximately 90% and 41%, respectively. Importantly, methylation in the kidney was inhibited by an average of 16.6+/-1.80% by endogenous norepinephrine released by renal artery nerve stimulation. Our results indicate that a robust 2-hydroxyestradiol methylation pathway exists in the kidney and heart, but not in the mesentery, and that this pathway is mediated by catechol-O-methyltransferase. Our findings also suggest that catecholamines may interfere with 2-hydroxyestradiol methylation and thereby attenuate the cardiorenal protective effects of 17beta-estradiol.  相似文献   
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