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491.
PURPOSE: To examine the impact of photodynamic therapy (PDT) on pigment epithelium derived factor (PEDF) expression in human choroidal neovascularization (CNV) membranes with regard to vascular endothelial growth factor (VEGF) expression. DESIGN: Interventional case series. METHODS: Retrospective review of interventional case series of 42 patients (42 eyes) who underwent removal of CNV. CNV was secondary to age-related macular degeneration (AMD) in all cases. Fifteen patients were treated with PDT, 3 to 246 days before surgery. CNV were stained for CD34, CD105, cytokeratin 18, VEGF, and PEDF. Twenty-seven CNV without previous treatment were used as control. RESULTS: Specimens without pretreatment disclosed varying degrees of vascularization, VEGF, and PEDF expression by different cells. Specimens treated by PDT, three days previously showed mostly occluded vessels lined with damaged endothelial cells (EC). In contrast, specimens excised at later time points after PDT were highly vascularized with healthy EC. This chronology was associated with an impressive VEGF immunoreactivity increased considerably in retinal pigment epithelial cells as well as significantly reduced PEDF expression in EC and stroma. CONCLUSIONS: PDT induces a selective vascular damage in CNV. The effectiveness of PDT, however, seems to be jeopardized by a rebound effect initiated by an enhanced VEGF and reduced PEDF expression in CNV.  相似文献   
492.
BackgroundTranscatheter aortic valve replacement (TAVR) is increasingly offered for aortic stenosis (AS) treatment in patients with a history of cancer. The impact of frailty on outcomes in this specific patient population is not well described.HypothesisFrailty is associated with mortality and poorer quality of life (QOL) outcomes in patients undergoing TAVR with a history of cancer.MethodsThis retrospective single center cohort study included AS patients who underwent TAVR from August 1, 2012 to May 15, 2020. Frailty was measured using serum albumin, hemoglobin, gait speed, functional dependence, and cognitive impairment. The primary outcome was a composite of all‐cause mortality and QOL at 1 year. A poor primary outcome was defined as either all‐cause mortality, Kansas City Cardiomyopathy Questionnaire overall summary (KCCQ‐OS) score <45 or a KCCQ‐OS score decline of ≥10 points from baseline. Regression analysis was used to determine the impact of frailty on the primary outcome.ResultsThe study population was stratified into active/recent cancer (n = 107), remote cancer (n = 85), and non‐cancer (n = 448). Univariate analysis of each cohort showed that frailty was associated with the primary outcome only in the non‐cancer cohort (p = .004). Multivariate analysis showed that cancer history was not associated with a poor primary outcome, whereas frailty was (1.7 odds ratio, 95% confidence interval [CI]: 1.1–2.8; p = .028).ConclusionsFrailty is associated with mortality and poor QOL in the overall and non‐cancer cohorts. Further investigation is warranted to understand frailty''s effect on the cancer population. Frailty should be heavily considered during TAVR evaluation.  相似文献   
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495.
This study was undertaken to compare the effects of alendronate and risedronate on bone mineral density (BMD) and bone turnover markers (BTMs) in late postmenopausal women with osteoporosis. Thirty women older than 60 y of age were randomly assigned to receive alendronate 10 mg (n=16) or risedronate 5 mg (n=14) on a daily basis. The patients were followed every 3 mo for 12 mo. BMD measurements were taken at baseline and at the end of the study, and BTMs were measured at 3-mo intervals. By the end of the study, there were statistically significant increases in BMD in both groups at all sites at which they were measured (P < .001). However, these differences were not statistically significant between groups. By the end of the study, all BTMs had decreased significantly and to a similar extent in both groups. The most significant change was observed in the third month of the study. A negative correlation was noted between percentage change in bonespecific alkaline phosphatase and femoral neck BMD (r=-0.467). This study reported no difference between the 2 drugs in their effects on BMD and BTMs.  相似文献   
496.
Postprandial lipoprotein metabolism is suggested to play a role in the pathogenesis of atherosclerosis. In this study, we investigated postprandial lipemia and its relationship to cardiovascular risk factors in patients with overt and subclinical hypothyroidism. Twentynine female patients with TSH levels greater than 5 μIU/mL and 12 euthyroid control female subjects were included in the study. Fifteen patients had subclinical hypothyroidism and 14 had overt hypothyroidism. All subjects underwent an oral lipid tolerance test. If triglyceride levels increased by 80% or more, subjects were considered postprandial lipemia positive. Control, overt hypothyroid, and subclinical hypothyroid groups were not statistically different with respect to anthropometric measurements, fasting blood C-reactive protein, uric acid, homocysteine, glucose, insulin, lipoprotein (a), apolipoprotein B levels, and homeostasis model assessment index. Fasting triglyceride levels correlated positively with TSH levels. Postprandial lipemia frequency was higher in overt hypothyroid subjects than in the control group. The subclinical hypothyroid group did not differ from the hypothyroid group with respect to postprandial lipemia frequency. In subjects with TSH levels higher than 5 μIU/mL, PPL risk was increased sevenfold. The results of this study show that postprandial triglyceride metabolism is affected in hypothyroidism.  相似文献   
497.
Soluble forms of selectins may play a regulatory role in inflammatory responses. The aim of this study was to examine the levels of serum-soluble (s) selectins in Behçet’s disease (BD) patients and to evaluate the associations of these molecules to disease activity, clinical findings, and drugs taken for BD, mainly colchicine. Serum sE-, sL-, and sP-selectins levels were measured by sandwich enzyme-linked immunosorbent assay in 28 BD patients and 22 healthy subjects. The BD patients were classified according to the disease activity, clinical findings, and therapy. Ten patients were newly diagnosed and were not taking any therapy. Remainder were on colchicine (n?=?18) and immunosuppressive drugs (n?=?5). In BD patients, the levels of sL- and sP-selectins were significantly lower than those of healthy controls, but sE-selectin level was similar to that of the controls. The patients on the therapy had significantly lower levels of sE- and sL-selectins and insignificantly lower level of sP-selectin than the patients not receiving therapy. The BD patients with active disease had significantly higher levels of sE-, sL-, and sP-selectins compared with the patients with inactive disease. There were no significant differences in the levels of selectins between the treated active patients and inactive patients. However, the untreated patients with active disease had significantly higher selectin levels than the inactive patients. There were no significant differences in all selectin levels between the patients with or without vascular involvement. Serum sL-selectin was found to be significantly higher in patients with erythema nodosum. In conclusion, our findings suggest that the levels of soluble selectin molecules in BD patients seem to be modified by the drugs taken for BD. The colchicine therapy is associated with lower selectin levels.  相似文献   
498.
OBJECTIVE: To investigate the pathogenesis of coronary slow flow (CSF), C-reactive protein (CRP) levels as indicator of inflammation and procoagulant activity were studied in patients with CSF. METHODS: Fifty-one patients (22 female, mean age; 53+/-10 years) who were admitted to our clinic with chest pain and had the diagnosis of CSF established by TIMI frame count method and coronary angiography, and 44 healthy subjects (18 female, mean age; 546 years) with normal coronary flow (NCF) were included in the study. Subjects with any infectious and systemic immune disease were excluded from the study. The CRP levels were measured from venous blood samples during admission, at 24th hour and after 3 months in all subjects. Additionally; fibrinogen, plasminogen, plasminogen activator inhibitor (PAI-1), tissue plasminogen activator (t-PA) and von Willebrand factor (vWF) levels were measured to determine the procoagulant activity. RESULTS: There was no significant difference between CRP levels of patients with CSF and healthy subjects during admission (7.26+/-4.2 ng/dl vs. 6.43+/-2.8 ng/dl, p>0.05), at 24th hour (7.84+/-1.3 ng/dl vs. 6.32+/-2.5 ng/dl, p>0.05) and after 3 months (6.37+/-2.4 ng/dl vs. 6.18+/-3.3 ng/dl, p>0.05). There were no differences between levels of CRP when compared according to the TIMI frame count, number of vessels with CSF and artery in which CSF was dominant. Additionally; procoagulant activity assessed by fibrinogen, plasminogen, PAI-1, t-PA and vWF levels was similar in both groups. CONCLUSION: Our findings on normal levels of CRP and procoagulant activity, and lack of relation with TIMI frame count made us to think that inflammatory and procoagulant activity did not play a role in the pathogenesis of CSF.  相似文献   
499.
Serum levels of proinflammatory cytokines, interleukin-1 beta (IL-1), tumor necrosis factor alpha, (TNF-), and their inhibitors, IL-1 receptor antagonist (IL-1ra) and soluble TNF receptor 1 (sTNFR1), were determined by enzyme-linked immunosorbent assay in 104 patients with Behçets disease (65 active, 39 inactive) and 40 healthy controls. The levels of IL-1 and IL-1ra were significantly higher in both active and inactive patients than in control subjects (P<0.01 and P< 0.01, respectively). The concentrations of TNF- and sTNFR1 were found to be higher in active patients than in controls (P< 0.01 and P< 0.001, respectively). There were no significant differences in the serum levels of these cytokines and their inhibitors between active and inactive patients. Significant increases in mean C-reactive protein level and erythrocyte sedimentation rate were found in patients with active vs inactive disease (P< 0.001 and P< 0.05, respectively). C-reactive protein values correlated with erythrocyte sedimentation rate but not with cytokines or their inhibitors. Our conclusion is that elevated serum TNF- and sTNFR1 seem to be important inflammatory mediators in Behçets disease. The statistically significant increase in these levels may arise from the severity of inflammation in the tissue or organ involved.  相似文献   
500.
Cellular response to hypoxia involves signaling via Smad proteins   总被引:10,自引:1,他引:10  
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