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41.
OBJECTIVE: Circulating endothelial progenitor cells (EPCs) differentiate into mature endothelial cells and regenerate the injured endothelium. The role of homeobox A9 (HOXA9) is critical for endothelial commitment during progenitor cell maturation, postnatal neovascularization and vascular repair. The objective of our study was to measure the expression of HOXA9 in CD34+ cells from hypertensive patients and to investigate its correlation with the number of circulating EPCs. METHODS: Thirty patients with newly diagnosed, never-treated essential hypertension and 30 age- and sex-matched normotensive controls were recruited for the study. Total RNA was extracted from peripheral CD34+ cells and quantitative real-time polymerase chain reaction for measurement of HOXA9 expression was performed. The number of CD34+/human kinase insert domain protein receptor + (KDR+) EPCs was measured and the Framingham risk estimated. RESULTS: Hypertensive patients had reduced HOXA9 expression compared to normotensive subjects (-26%, P < 0.001), and lower levels of peripheral CD34+/KDR+ EPCs (421 +/- 93 versus 582 +/- 101, P < 0.001). HOXA9 expression was inversely associated with systolic blood pressure (r = -0.54, P < 0.001) and the Framingham risk (r = -0.50, P < 0.001). A direct association was observed between the number of EPCs and HOXA9 expression (r = 0.50, P < 0.001), which was independent of blood pressure levels and Framingham risk. In a subgroup of 15 hypertensive patients, a 4-week treatment with ramipril was associated with a significant 15% increase in HOXA9 expression and 25% increase in EPC levels. CONCLUSIONS: In hypertensive patients, downregulation of HOXA9 expression in peripheral CD34+ cells may have a role in the loss of circulating EPCs, thus potentially impairing postnatal neovascularization and vascular repair.  相似文献   
42.
The endocrine function of adipose tissue: an update   总被引:9,自引:0,他引:9  
Adipose tissue secretes bioactive peptides, termed 'adipokines', which act locally and distally through autocrine, paracrine and endocrine effects. In obesity, increased production of most adipokines impacts on multiple functions such as appetite and energy balance, immunity, insulin sensitivity, angiogenesis, blood pressure, lipid metabolism and haemostasis, all of which are linked with cardiovascular disease. Enhanced activity of the tumour necrosis factor and interleukin 6 are involved in the development of obesity-related insulin resistance. Angiotensinogen has been implicated in hypertension and plasminogen activating inhibitor-1 (PAI-1) in impaired fibrinolysis. Other adipokines like adiponectin and leptin, at least in physiological concentrations, are insulin sparing as they stimulate beta oxidation of fatty acids in skeletal muscle. The role of resistin is less understood. It is implicated in insulin resistance in rats, but probably not in humans. Reducing adipose tissue mass, through weight loss in association with exercise, can lower TNF-alpha and IL-6 levels and increase adiponectin concentrations, whereas drugs such as thiazolinediones increase endogenous adiponectin production. In-depth understanding of the pathophysiology and molecular actions of adipokines may, in the coming years, lead to effective therapeutic strategies designed to protect against atherosclerosis in obese patients.  相似文献   
43.
PURPOSE: Supratentorial pilocytic astrocytomas in adults are uncommon. A prospective clinical trial was conducted to obtain clinical and outcome data in these patients. METHODS AND MATERIALS: Between 1986 and 1994, 20 eligible adults with supratentorial pilocytic astrocytomas were enrolled in a prospective intergroup trial of radiotherapy (RT) after biopsy (3 patients) or observation after gross (11 patients) or subtotal (6 patients) resection. RESULTS: At the time of analysis (median follow-up, 10 years), 1 patient (5%) had died and 19 patients (95%) were alive. The 5-year progression-free and overall survival rates were 95%. The cause of death in the patient who died (2.1 years after enrollment) was unknown; a radiographic examination obtained shortly before the patient's demise revealed no signs of progression. Progression in 1 patient approximately 1 month after enrollment required injection of (32)P into an enlarging cyst. The patient required RT approximately 18 months later because of further progression. This patient was alive without evidence of progression 9 years after RT. No toxic effects had been recorded at the latest follow-up examinations. CONCLUSION: With follow-up comparable or superior to that in many retrospective studies, the results of this prospective trial confirm that adults with pilocytic astrocytomas have a favorable prognosis with regard to survival and neurologic function. The vast majority of patients remained stable after gross or subtotal resection and no adjuvant therapy. RT need not be offered to adults with supratentorial pilocytic astrocytoma after gross or subtotal resection; instead, close observation is recommended. Because only 3 patients received RT after biopsy, it is difficult to comment on the effect of RT on their outcome as a group.  相似文献   
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Brown PD  Brown CA  Pollock BE  Gorman DA  Foote RL 《Neurosurgery》2002,51(3):656-65; discussion 665-7
OBJECTIVE: Our aim was to evaluate the efficacy of stereotactic radiosurgery (SRS) for the treatment of patients with brain metastases that have been determined to be "radioresistant" on the basis of histological examination. METHODS: We reviewed the medical records of 41 consecutive patients who presented with 83 brain metastases from radioresistant primaries and subsequently underwent SRS. All patients were followed until death or for a median of 31 months after SRS. Tumor histologies included renal cell carcinoma (16 patients), melanoma (23 patients), and sarcoma (2 patients). Eighteen patients (44%) had a solitary metastasis, and 23 patients (56%) had multiple metastases. RESULTS: The median overall survival time was 14.2 months after SRS. On the basis of univariate analysis, systemic disease status (P = 0.006) and Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class (P = 0.005) were associated with survival. The median survival time was 23.5 months for patients in RPA Class I status and 10.5 months for patients in RPA Class II or III status. There was a trend (P = 0.12) toward improved median survival for patients with renal cell carcinoma (17.8 mo) as compared with patients with melanoma (9.7 mo). Multivariate analysis showed RPA class (P = 0.038) and histological diagnosis of primary tumor (P < 0.001) to be independent predictors for overall survival. In the 35 patients who underwent follow-up imaging, 9 (12%) of 73 tumors recurred locally. In 54% of the patients, distant brain failure (DBF) developed. Whole brain radiotherapy (WBRT) improved local control and decreased DBF, according to the univariate and multivariate analyses. Patients who received adjuvant WBRT in addition to SRS had 6-month actuarial local control of 100% as compared with 85% among those who did not receive WBRT (P = 0.018). Patients who received adjuvant WBRT with SRS had a 6-month actuarial DBF rate of 17%, as compared with a rate of 64% among patients who had SRS alone (P = 0.0027). CONCLUSION: Well-selected patients with brain metastases from radioresistant primary tumors who undergo SRS survive longer than historical controls. RPA Class I status and primary renal cell carcinoma predict longer survival. Adjuvant WBRT improves local control and decreases DBF but does not affect overall survival. Further studies are needed to determine which patients should receive WBRT.  相似文献   
47.
Statins are able to reduce cardiovascular morbility and mortality mainly through their hypocholesterolemic effect. Beyond the inhibition of cholesterol synthesis, the identification of "ancillary" mechanisms has motivated studies evaluating the relationship between the use of statins and the modification of bone mineral density (BMD). To date, clinical trials have provided discordant results. The aim of our study was to evaluate whether simvastatin treatment (40 mg/d) could modify BMD in hypercholesterolemic women (n = 40) after a 2-year treatment as compared with a control group treated only with diet (n = 20) and matched by gender, age, body mass index (BMI), lipids, menopausal age, and BMD and the number of osteopenic, osteoporotic, and normal women (on the basis of T-score value). Exclusion criteria were secondary hyperlipemias and osteoporosis and current or previous therapy with statins, bisphosphonates, and estrogens. The BMD was measured at the lumbar spine and hip by dual energy x-ray absorpiometry (DEXA). In the group treated by simvastatin, BMD, both on the spine and femoral hip, showed a significant increase after 8 and 24 months, respectively (0.878 +/- 0.133 v 0.893 +/- 0.130 and 0.907 +/- 0.132; 0.840 +/- 0.101 v 0.854 +/- 0.101; and 0.863 +/- 0.10, P <.001); there was a percentage increase of 1.7% after 8 months and 3.3% after 24 months at the spine; at the femoral hip, BMD increased 1.6% after 8 months and 2.7% after 24 months. The group treated only with hypolipidic diet demonstrated after 8 and 24 months a slight decrease in BMD both on the spine and femoral hip (respectively, 0.884 +/- 0.175 v 0.872 +/- 0.174 and 0.861 +/- 0.164; 0.860 +/- 0.110 v 0.853 +/- 0.096 and 0.847 +/- 0.095; P <.05). In conclusion, as partly suggested by retrospective or observational data, this longitudinal study indicates that simvastatin treatment exerts a beneficial effect on BMD.  相似文献   
48.
Brain natriuretic peptide (BNP) levels were measured in 100 patients with coronary heart disease (CHD) who underwent myocardial stress thallium-201 single-photon emission computed tomography (30 with stable angina without basal electrocardiographic ischemia and no perfusion defects, 31 with angina with electrocardiographic ischemia and reversible perfusion defects, and 39 with myocardial infarction and irreversible defects) and in 42 controls. BNP levels progressively increased in patients with CHD and were significantly greater in patients with ischemia (p <0.01) and infarction (p <0.001) compared with controls and subjects with angina. BNP concentration was correlated positively (r = 0.923, p <0.001) with perfusion defect extent and inversely (r = -0.690, p <0.001) with the left ventricle ejection fraction (not different in the subjects examined).  相似文献   
49.
An 18-month-old infant with Down's syndrome presented with a symptomatic esophageal diverticulum (ED) located at the cervical esophagus. He had been operated on successfully for an esophageal atresia and distal tracheoesophageal fistula in the newborn period. Neither surgical maneuvers nor esophageal trauma could explain the ED, which was resected through a cervical approach.  相似文献   
50.
Management of Blunt and Penetrating Injuries to the Porta Hepatis   总被引:1,自引:1,他引:0       下载免费PDF全文
Injuries to the porta hepatis pose difficult problems in management, and transection of the bile ducts, portal vein and hepatic artery is among the most challenging. Twenty-one patients with severe injuries to the porta hepatis were treated over a ten-year period. Ages ranged from 13 to 56 years, and follow-up was up to nine years. Among the 14 patients with bile duct injury, eight were found to have complete transection, and five suffered a tangential laceration or incomplete disruption with a portion of a duct wall remaining intact. Five of the eight patients who had complete transection underwent primary end-to-end repair with T-tube splinting, while three were treated with primary Roux-en-Y choledocojejunostomy. All patients with incomplete disruption underwent primary repair with or without T-tube splinting. Of the five patients with complete disruption who were treated with primary end-to-end anastomosis of the bile duct in conjunction with T-tube splinting, all required secondary biliary tract reconstruction of some type. No patient with complete transection that was treated with primary Roux-en-Y biliary enteric anastomosis required reoperation. Partial transections were successfully treated with primary repair. Portal vein injury was encountered in ten patients. Injury was successfully managed by primary closure, interposition of a vein, or splenicmesenteric vein bypass. Associated injuries to liver, pancreas, kidney and duodenum were common. In four patients there was injury to the main or left or right hepatic artery which was managed successfully by repair or ligation, with or without hepatic lobectomy. By adhering to the principles of management to be outlined, many patients with injury to the porta hepatis will survive, and the long term outcome can be gratifying.  相似文献   
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