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1.
The objectives of this study were to determine the relationship between carotid-femoral (cfPWV) and aortic pulse wave velocity (aPWV) and to compare their modulators and association with coronary artery disease (CAD). We studied 107 consecutive patients (68 men) with a mean age of 60.49+/-8.31 years who had stable angina and had been referred for coronary angiography. cfPWV and aPWV were measured simultaneously during cardiac catheterization using the Complior device and aortic pressure waveform recordings, respectively. Based on the presence or absence of significant coronary artery stenosis (CAS) patients were subdivided into a CAS+ or CAS- group. The mean values of cfPWV and aPWV were 10.65+/-2.29 m/s and 8.78+/-2.24 m/s, respectively. They were significantly higher in the CAS+ (n=71) compared with the CAS- (n=36) group and predicted significant CAS independently of cardiovascular risk factors and mean or systolic aortic blood pressure. aPWV and cfPWV were significantly correlated (r=0.70; p<0.001) but the degree of correlation differed significantly (p<0.03) between the CAS+ (r=0.74, p<0.001) and CAS- group (r=0.46, p=0.003). Age and mean aortic blood pressure were independent predictors for aPWV as well as cfPWV. In the receiver operating characteristic (ROC) analysis, aPWV and cfPWV had similar accuracy in identification of significant CAS (AUC [area under the ROC curve]=0.76 and 0.69, respectively; p=0.13). However, neither cfPWV nor aPWV was effective at differentiating the extent of CAD. In conclusion, aPWV and cfPWV are highly correlated parameters with similar determinants and comparable accuracy in predicting significant CAS. The strength of correlation between these two indices differed significantly between subjects with and those without CAS.  相似文献   
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The possibility to use the colorimetric MTT assay for measuring proliferation and cell death of human peripheral blood lymphocytes (PBL) was studied. In a range from 100,000-800,000 cells/well a linear correlation between the optical signal (OD signal at 570 nm) and the cell number was found. It is necessary to incubate the cells with the MTT at least 2 hours. After stimulation by different PHA concentrations a very good correlation between [3H] thymidine incorporation and MTT assay was found. A comparison of daunomycin cytotoxicity, measurement by trypan blue exclusion and MTT assay, gave also a good correlation between both methods. It can be pronounced that the MTT assay is a suitable method to measure cell proliferation and cell death of human PBL. The assay is easy to handle, a large number of probes can be assayed in a relatively short time and no radioactivity is necessary. For the measurement of the colored product a common ELISA reader can be used.  相似文献   
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Background: Pars planta vitrectomy has evolved as an alternative method in the treatment of more complicated rhegmatogenous retinal detachments. We report a series of patients who underwent primary vitrectomy with gas tamponade without the use of additional scleral buckling. Methods: A retrospective study of 53 patients with a follow-up of 6–45 months (mean 17.8 months) was carried out. Preoperative findings included unusual, multiple or large breaks, vitreous haemorrhage, proliferative vitreoretinopathy and bullous retinal detachment. Preoperative visual acuity was between light perception and 1.0, with 30% (16/53) of patients with 0.4 or better. Results: Retinal reattachment was achieved in 64% of cases (34/53) with one and in 92% (49/53) with one or more operations. Final visual acuity was between light perception and 1.0, with 41% (22/53) of patients with 0.4 or better. Cataract formation occurred in 86% (37/43) of all patients with a clear lens preoperatively. Macular pucker was noted in 11 % (6/53) and postoperative proliferative vitreoretinopathy causing redetachment in 6% (3/53). Conclusion: With primary vitrectomy, a high final anatomical success rate with few intraoperative complications can be achieved in more complicated forms of rhegmatogenous retinal detachment. The major drawback of the procedure is the high incidence of post-operative cataract formation.  相似文献   
4.
PURPOSE: The human ELAV (embryonic lethal abnormal vision)-like protein HuR stabilizes a certain group of cellular mRNAs that contain AU-rich elements in their 3'-untranslated region. Cell culture studies have shown that the mRNA of cyclooxygenase (COX)-2 can be stabilized by HuR. EXPERIMENTAL DESIGN: To investigate a possible contribution of dysregulation of mRNA stability to the progression of cancer and to overexpression of COX-2, we studied expression of HuR in 208 primary breast carcinomas by immunohistochemistry. RESULTS: There were two different staining patterns of HuR in tumor tissue of breast carcinomas: nuclear expression was seen in 61% of cases; and an additional cytoplasmic expression was seen in 30% of cases. Expression of HuR was significantly associated with increased COX-2 expression; this association was particularly significant for cytoplasmic HuR expression (P < 0.0005). We further observed a significant association of cytoplasmic (P = 0.002) or nuclear HuR (P = 0.027) expression with increased tumor grade. Only 13% of the grade 1 carcinomas showed cytoplasmic expression of HuR, compared with 46% of the grade 3 carcinomas. There was no significant correlation between HuR expression and other clinicopathological parameters such as histological type, tumor size, or nodal status as well as patient survival. CONCLUSIONS: Our results suggest that overexpression of HuR in tumor tissue may be part of a regulatory pathway that controls the mRNA stability of several important targets in tumor biology, such as COX-2. Based on our results, additional studies are necessary to investigate whether HuR might be a potential target for molecular tumor therapy.  相似文献   
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OBJECTIVE: Heart failure is associated with reduced function of sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a) but increased function of sarcolemmal Na+/Ca2+ exchanger (NCX), leading to decreased SR Ca2+ content and loss of frequency-potentiation of contractile force. We reported that SERCA2a-overexpression in transgenic rat hearts (TG) results in improved contractility. However, it was not clear whether TG have improved contractility due to frequency-dependent improved SR Ca2+ handling. METHODS: Therefore, we characterized TG (n=35) vs. wild-type (WT) control rats (n=39) under physiological conditions (37 degrees C, stimulation rate <8 Hz). Twitch force, intracellular Ca2+ transients ([Ca2+]i), and SR Ca2+ content were measured in isolated muscles. The contribution of transsarcolemmal Ca2+ influx (I(Ca)) through L-type Ca2+ channels (LTCC) and reverse mode NCX (I(Na/Ca)) to Ca2+ cycling were studied in isolated myocytes. RESULTS: With increasing frequency, force increased in TG muscles by 168+/-35% (8 Hz; P<0.05) and SR Ca2+ content increased by maximally 118+/-31% (4 Hz; P<0.05). In WT, there was a flat force-frequency response without changes in SR Ca2+ content. Relaxation parameters of force and [Ca2+]i decay were accelerated at each frequency in TG vs. WT by approximately 10%. At prolonged rest intervals (<240 s), force and SR Ca2+ content increased significantly more in TG. Consequently, absolute SR Ca2+ content measured in myocytes was increased approximately 2-fold in TG. Transsarcolemmal Ca2+ fluxes estimated by I(Ca) (at 0 mV -10.2+/-1.1 vs. -16.9+/-1.3 pA/pF) and I(Na/Ca) (0.17+/-0.02 vs. 0.46+/-0.05 pA/pF) were decreased in TG vs. WT (P<0.05), whereas NCX and LTCC protein expression was only slightly reduced (P=n.s.). CONCLUSION: In summary, SERCA2a-overexpression improved contractility in a frequency-dependent way due to increased SR Ca2+ loading whereas transsarcolemmal Ca2+ fluxes were decreased.  相似文献   
10.
Background and purposeVertebrobasilar artery calcification (VBAC) has been associated with increased stroke occurrence. Little is known on VBAC risk factors, especially for patients with cardiovascular disease. We aimed to assess risk factors associated with VBAC in a cohort of cardiovascular patients referred for a head computed tomography (CT) scan.Materials and methodsAll patients who underwent a clinically indicated, unenhanced, thin slice head CT 6 months before or after inclusion in the SMART study were included. CTs were assessed for presence of VBAC (dichotomously). Relative risks of the associations of age, sex, diabetes mellitus (DM), obesity, body mass index, estimated glomerular filtration rate, hypertension, hyperlipidemia, use of lipid lowering medication, smoking status, high sensitivity C-reactive protein, ankle-brachial index (ABI; ≤ 0.90, ≥ 1.30, continuous), internal carotid artery stenosis ≥ 70%, and carotid intima-media thickness (IMT) with VBAC were estimated using Poisson regression analysis with robust standard errors, adjusted for age and sex.ResultsOf the 471 patients included (57% male, median age 58 [interquartile range 47–63]), 117 (24.8%) showed VBAC. Presence of VBAC was associated with older age (RR per 10 years = 1.70 [95%CI 1.46–1.99]), DM (RR = 1.45 [95%CI 1.03–2.06]), obesity (RR = 1.53 [95%CI 1.10–2.12]), ABI ≤ 0.90 (RR = 1.57 [95%CI 1.02–2.41]), and an increased carotid IMT (RR = 2.60 per mm [95%CI 1.20–5.62]). Other measurements were not associated with VBAC.ConclusionsWe identified several markers associated with VBAC in patients with cardiovascular disease referred for a head CT. Future investigation into the relationship between VBAC and stroke is warranted to determine the potential of VBAC in stroke prevention.  相似文献   
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