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31.
OBJECTIVES: Restenosis is the major limitation of coronary interventions occurring in nearly a third of the patients undergoing percutaneous transluminal coronary angioplasty (PTCA) with no single, definite predictor demonstrated in an individual patient. Platelets are known to play an important role in the pathogenesis of subsequent restenosis. METHODS AND RESULTS: In a prospective study, follow-up coronary angiographies were performed in 102 consecutive patients with stable angina who underwent a successful PTCA for single-vessel coronary artery disease. Demographics, baseline lipid profiles (total cholesterol, HDL- and LDL-cholesterol, triglycerides) and haematological parameters (red cell, white cell and platelet counts, haemoglobin concentration, haematocrite %, mean platelet volume, platelet mass and fibrinogen levels) were compared between patients with and without restenosis. In the restenosis group, mean platelet volume (8.82 +/- 0.78 fl vs. 8.13 +/- 0.64 fl, p < 0.001), white cell count (8673 +/- 322 x 10(3)/microl vs. 7513 +/- 232 x 10(3)/microl, p < 0.01) and fibrinogen level (4.2 +/- 1.4 g/l vs 3.6 +/- 1.1 g/l) were significantly higher. The relative odds for developing angiographically defined restenosis were 2.49 times greater in diabetics (p = 0.11) and 2.54 times greater in men (p = 0.13). It is 1.43 times greater in patients with higher fibrinogen levels (p = 0.16). But, the relative odds for developing restenosis were 10.43 times greater in patients with larger pre-procedural mean platelet volumes (p < 0.01). CONCLUSIONS: There was a positive correlation between mean platelets volume and loss in luminal diameter between post-angioplasty and follow-up angiographies (r = +2.345, p = 0.01). There was no association between restenosis and haemoglobin, haematocrit, red cell count, white cell count, platelet count, platelet mass and plasma fibrinogen level. The development of restenosis after successful coronary angioplasty may be mainly influenced by the platelet size. 相似文献
32.
Impact of p53 and Ki-67 in predicting recurrence and progression of superficial (pTa and pT1) urothelial cell carcinomas of urinary bladder 总被引:1,自引:0,他引:1
Kilicli-Camur N Kilicaslan I Gulluoglu MG Esen T Uysal V 《Pathology international》2002,52(7):463-469
In predicting the aggressive behavior of bladder tumors, the histopathological characteristics of grade and invasive stage are of principal importance. However, for predicting tumor recurrence and progression, these are sufficient only to a limited extent, particularly in the case of superficial (pTa and pT1) urothelial cell carcinomas. New prognostic factors are therefore needed to avoid either insufficient or excessive treatment. In this retrospective study, we investigated the prognostic value of the p53 and Ki-67 immunoreactivity indices. The present study included 118 superficial urinary bladder tumors consisting of 58 recurrent and 60 non-recurrent cases. Twenty of the recurrent tumors progressed into a higher grade and/or invasive stage. Paraffin immunohistochemical analysis was carried out using anti-p53 and anti-Ki-67 antibodies on the initial tumor tissues. We concluded that there is a highly significant relationship between the p53 and Ki-67 immunoreactivities and the histological grade and pathological stage of the tumors (P < 0.0001). We observed a significant relationship between the presence of recurrence and progression and the p53 immunoreactivity index (P < 0.01 and P = 0.017, respectively) and Ki-67 immunoreactivity index (P < 0.0001 and P = 0.046, respectively). Positivity for p53 and Ki-67 can demonstrate the risk of recurrence (p53: sensitivity = 76%, specificity = 58%; Ki-67: sensitivity = 86%, specificity = 48%) and progression (p53: sensitivity = 80%, specificity = 46%; Ki-67: sensitivity = 85%, specificity = 36%; ). We believe that both of these immunohistochemical markers can be considered valuable in addition to classical histopathological prognostic parameters for predicting recurrence and progression risks. 相似文献
33.
Sex hormone metabolism in prostate cancer cells during transition to an androgen-independent state 总被引:3,自引:0,他引:3
Härkönen P Törn S Kurkela R Porvari K Pulkka A Lindfors A Isomaa V Vihko P 《The Journal of clinical endocrinology and metabolism》2003,88(2):705-712
The progression of prostate cancer during androgen deprivation therapy is a serious clinical problem. Little is known, however, about the mechanisms behind the transition of the disease to an androgen-independent stage. In the present report, we provide evidence of substantial changes in both estrogen and androgen metabolism during the transition of cultured prostate cancer LNCaP (lymph node carcinoma of the prostate) cells. The results of enzyme activity measurements performed using HPLC suggest that, related to the transition, there exists a remarkable decrease in the oxidative 17 beta-hydroxysteroid dehydrogenase (17HSD) activity, whereas the reductive 17HSD activity seems to increase. Relative quantitative RT-PCR revealed that the decrease in oxidative activity largely coincided with the remarkable decrease in the expression of the HSD17B2 gene. Furthermore, the present data suggest that the observed increasing activity of 17HSD type 7 could lead to the increased intracellular production of 17 beta-estradiol during disease progression. This was supported by the cDNA microarray screening results, which showed a considerable overexpression of several estrogen up-regulated genes in the LNCaP cell line variant that represents progressive prostate cancer. Because 17HSDs critically contribute to the control of bioavailability of active sex steroid hormones locally in the prostate, the observed variation in intraprostatic 17HSD activity might be predicted to be crucially involved in the regulation of growth and function of the organ. 相似文献
34.
Kural AR Demirkesen O Onal B Obek C Tunc B Onder AU Yalcin V Solok V 《Urologia internationalis》2003,71(2):190-196
INTRODUCTION: The increase in the detection of renal tumors incidentally in earlier stages has enhanced the enthusiasm for nephron-sparing surgery (NSS). PATIENTS AND METHODS: We performed NSS in 76 patients (53 male, 23 female) with a mean age 52.3 between December 1988 and September 2001. Patients were sub-classified into 2 groups as elective or imperative indication group. They were compared regarding surgical technique, time of surgery, pathological analysis, complications, and disease free status. RESULTS: Elective indication group (group I) with a normal contralateral kidney consisted of 50 patients, whereas there were 26 patients in the imperative indication group (group II). Tumors were incidentally detected in 63%; 74% in group I and 42% in group II. Although the mean diameter of the tumor was slightly higher in group II (39.1 vs. 36.3 mm), this difference did not reach statistical significance (p > 0.05). The partial nephrectomy was performed more frequently compared to enucleation in group I (90 vs. 69%, p = 0.050). However, the mean operation time as well as the mean clamping time did not differ significantly between the two groups (p > 0.05). In the histological evaluation tumors were benign in 16 (21%) and malignant in 60 patients. All of the patients but one with renal cell carcinoma had stage T1-T2 disease. Major complications were observed in 14 (18%) and 12 were from group II. Complication rate was significantly higher in group II (p = 0.000). Of 60 patients with renal cell carcinoma, 2 died of unrelated causes. One patient died with multiple visceral metastases. One patient was lost to follow-up. In the remaining 56 patients with a mean follow-up of 37.1 months (1-152), local recurrence or distant metastases were not detected. Serum creatinine levels have remained almost the same compared to preoperative levels (1.2 +/- 0.6 vs. 1.5 +/- 0.9). Overall and cancer-specific survivals were 100 and 100% in group I, 85 and 95% in group II, and 94 and 98% for the entire patient population, respectively. CONCLUSION: NSS is an effective and reliable treatment in low stage renal tumors. It prevents unnecessary nephrectomy in benign lesions that could not be diagnosed preoperatively. However, the patients who underwent NSS with elective indication outcome with better results, compared to those with imperative indication. 相似文献
35.
Cantasdemir M Kantarci F Numan F Mihmanli I Kalender B 《Cardiovascular and interventional radiology》2003,26(1):85-87
We report the use of a metallic stent in a
transplant ureteral stenosis. A 28-year-old man with chronic renal
failure due to chronic pyelonephritis, who received a living-donor
renal transplant, presented with transplant ureteral stenosis. The
stenosis was unresponsive to balloon dilation and was treated by
antegrade placement of a self-expanding Memotherm stent. The stented
ureter stayed patent for 3 years. It may be reasonable to treat
post-transplant ureteral stenosis resistant to balloon dilation with
self-expanding metallic stents. However, long-term follow-up is
required to evaluate the efficacy of this treatment. 相似文献
36.
17β‐hydroxysteroid dehydrogenases in normal human mammary epithelial cells and breast tissue 总被引:3,自引:0,他引:3
Miettinen M Mustonen M Poutanen M Isomaa V Wickman M Söderqvist G Vihko R Vihko P 《Breast cancer research and treatment》1999,57(2):175-182
17hydroxysteroid dehydrogenase activity represents a group of several isoenzymes (17HSDs) that catalyze the interconversion between highly active 17hydroxy and low activity 17ketosteroids and thereby regulate the biological activity of sex steroids. The present study was carried out to characterize the expression of 17HSD isoenzymes in human mammary epithelial cells and breast tissue. In normal breast tissues 17HSD types 1 and 2 mRNAs were both evenly expressed in glandular epithelium. In two human mammary epithelial cell lines, mRNAs for 17HSD types 1, 2 and 4 were detected. In enzyme activity measurements only oxidative 17HSD activity, corresponding to either type 2 or type 4 enzyme, was present. The role of 17HSD type 4 in estrogen metabolism was further investigated, using several cell lines originating from various tissues. No correlation between the presence of 17HSD type 4mRNA and 17HSD activity in different cultured cell lines was detected. Instead, oxidative 17HSD activity appeared in cell lines where 17HSD type 2 was expressed and reductive 17HSD activity was present in cells expressing 17HSD type 1. These data strongly suggest that in mammary epithelial cell lines the oxidative activity is due to type 2 17HSD and that oxidation of 17hydroxysteroids is not the primary activity of the 17HSD type 4 enzyme. 相似文献
37.
38.
Aktaş Z Ozdek S Asli Dinç U Akyürek N Atalay V Güz G Hasanreisoglu B 《Nephrology (Carlton, Vic.)》2007,12(4):380-385
AIM: Ocular surface changes and ocular symptoms may be encountered in patients with chronic renal failure (CRF) undergoing haemodialysis. The ocular surface changes and its relationship with metabolic control in CRF patients were aimed to be emphasized in this study. METHODS: Thirty-eight CRF patients (75 eyes) undergoing haemodialysis were enrolled. Patients underwent a complete ocular examination together with Schirmer, tear break-up time tests, pachymetric measurements and conjunctival impression cytologies. Blood calcium, phosphate levels and total body volume changes after haemodialysis were recorded. RESULTS: The most common findings were conjunctival calcification with red eye (81.3%) and dry eye (62.7%, according to tear break-up time test) in 75 eyes of 38 patients. Impression cytologies were graded as 0 in 57.3% of eyes and 2-3 in 40% of eyes showing positive correlation with the extent of conjunctival calcification (R = 0.486, P = 0.0001). Serum calcium and phosphate levels were also positively correlated with the degree of conjunctival calcification (R = 0.684, P = 0.0001 and R = 0.428, P = 0.0001, respectively) as well as with the grades of impression cytology (R = 0.587, P = 0.0001 and R = 0.385, P = 0.0001, respectively). Furthermore, the mean corneal thickness decreased significantly (9.31 +/- 26.9 mum) following haemodialysis (Paired t-test, P = 0.002). CONCLUSION: Dry eye and irritational symptoms are major ocular symptoms in CRF patients. Serum calcium and phosphate levels seem to have a prognostic importance for the ocular findings and symptoms in patients with CRF. 相似文献
39.
Veli K. Topkara Srikanth Kondareddy Douglas L. Mann 《Current heart failure reports》2009,6(4):229-235
Myocardial infarction initiates progressive changes in the biology of the myocyte and nonmyocyte components of the myocardium,
as well as the geometry of the left ventricle. Despite the use of evidence-based strategies to postmyocardial infarction,
heart failure supervenes and is attended by an unacceptably high mortality rate. Given that left ventricular (LV) remodeling
may contribute independently to disease progression, several innovative approaches have been designed to attenuate and reverse
LV remodeling. This review discusses the emerging role of epicardial restraint devices in the treatment of postmyocardial
cardiac remodeling. 相似文献
40.
Goksel Cagirci M.D. Serkan Cay M.D. Ozlem Karakurt M.D. Neslihan Eryasar M.D. Veli Kaya M.D. Aytun Canga M.D. Asuman Bicer Yesilay M.D. Harun Kilic M.D. Serkan Topaloglu M.D. Dursun Aras M.D. Ahmet Duran Demir M.D. Ramazan Akdemir M.D. 《Annals of noninvasive electrocardiology》2009,14(4):327-332
Background: Cigarette smoking increases the risk of cardiovascular events related with several mechanisms. The most suggested mechanism is increased activity of sympathetic nervous system. Heart rate variability (HRV) and heart rate turbulence (HRT) has been shown to be independent and powerful predictors of mortality in a specific group of cardiac patients. The goal of this study was to assess the effect of heavy cigarette smoking on cardiac autonomic function using HRV and HRT analyses. Methods: Heavy cigarette smoking was defined as more than 20 cigarettes smoked per day. Heavy cigarette smokers, 69 subjects and nonsmokers 74 subjects (control group) were enrolled in this study. HRV and HRT analyses [turbulence onset (TO) and turbulence slope (TS)] were assessed from 24‐hour Holter recordings. Results: The values of TO were significantly higher in heavy cigarette smokers than control group (?1.150 ± 4.007 vs ?2.454 ± 2.796, P = 0.025, respectively), but values of TS were not statistically different between two groups (10.352 ± 7.670 vs 9.613 ± 7.245, P = 0.555, respectively). Also, the number of patients who had abnormal TO was significantly higher in heavy cigarette smokers than control group (23 vs 10, P = 0.006). TO was correlated with the number of cigarettes smoked per day (r = 0.235, P = 0.004). While LF and LF/HF ratio were significantly higher, standard deviation of all NN intervals (SDNN), standard deviation of the 5‐minute mean RR intervals (SDANN), root mean square of successive differences (RMSSD), and high‐frequency (HF) values were significantly lower in heavy smokers. While, there was significant correlation between TO and SDNN, SDANN, RMSSD, LF, and high frequency (HF), only HF was correlated with TS. Conclusion: Heavy cigarette smoking has negative effect on autonomic function. HRT is an appropriate noninvasive method to evaluate the effect of cigarette on autonomic function. Simultaneous abnormal HRT and HRV values may explain increased cardiovascular event risk in heavy cigarette smokers. 相似文献