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61.
62.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by fibrofatty replacement of the right ventricular myocardium. Recently, the myocardial loss in ARVC has been suggested to be related to apoptosis. However, it is still unknown whether this phenomenon is already established in the myocardium of pediatric cases with this disease. We examined the histopathologic characteristics of the ventricular myocardium in specimens obtained from 10 patients, including 3 children with ARVC, and investigated the occurrence of apoptosis in the myocardium by terminal deoxyribonucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assay and agarose-gel electrophoresis of DNA. Endomyocardial biopsy specimens from the 10 cases and a necropsy sample from one adult case with ARVC were examined. Histopathologic examination of biopsy specimens from the pediatric cases revealed extensive fibrosis. Typical fatty infiltration was demonstrated in one of the 3 pediatric cases. These findings were similar to those in adult cases; the histopathologic index based on the severity of myocardial damage, including myocyte degeneration and fibrosis, was not significantly different from that in adult cases. TUNEL assay revealed positive reactivity of the myocardial cells. The apoptotic index was 1.4 +/- 0.4% in children and 1.6 +/- 0.5% in adults (difference not statistically significant). Agarose-gel electrophoresis of a DNA extract of the myocardial tissue of the autopsy case revealed DNA fragmentation. Cases with idiopathic ventricular tachycardia and control cases with a cardiac transplant (with no rejection) had minimal histopathologic findings and negative reactivity in the TUNEL assay. These results indicate that myocardial damage is already established in cases diagnosed as ARVC in childhood, and suggest that the myocardial damage is closely related to apoptosis in children, as well as in adults, in this disease.  相似文献   
63.
Although the clinical utility of a frozen section analysis (FSA) at the time of radical cystectomy (RC) has already been established, its significance and utility in bladder cancer patients receiving neoadjuvant chemotherapy (NAC) have not yet been fully evaluated. We identified 458 patients (937 ureters) who underwent open RC for bladder cancer at our 7 Japanese institutions between 2004 and 2015. Among these patients, 139 (284 ureters) received NAC before RC (NAC group), while 319 (653 ureters) underwent RC alone (non-NAC group). FSA was performed on 356 out of 937 (38.0%) ureters and 179 out of 458 (39.1%) patients. FSA was positive in 30 out of 356 (8.4%) ureters and its sensitivity, specificity, and accuracy were 89.3, 98.5, and 97.8%, respectively. In the NAC group, FSA was performed on 138 out of 284 (48.6%) ureters and 68 out of 139 (48.9%) patients. FSA was positive in 8 out of 138 ureters (5.8%), and its sensitivity, specificity, and accuracy were 77.8, 99.2, and 97.8%, respectively. In the non-NAC group, FSA was performed on 218 out of 653 (33.4%) ureters and 111 out of 319 (34.8%) patients. FSA was positive in 22 out of 218 (10.1%) ureters, and its sensitivity, specificity, and accuracy were 94.7, 98.0, and 97.7%, respectively. No correlation was observed between preoperative clinical factors and FSA positivity in the NAC group; however, in the non-NAC group, the incidence of FSA positivity in the ureters of patients with concomitant CIS in TUR-BT specimens was 8/41 (19.5%), which was significantly higher than that in their counterpart (14/177, 7.9%, p = 0.033). Even in the era of NAC in the management of bladder cancer patients, the performance of FSA does not change and FSA at the time of RC may provide useful diagnostic information.  相似文献   
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65.
12 young men developed allergic contact dermatitis from wearing yellow cotton sweaters. We attempted to identify the causative agents by an experimental screening method in animals. Guinea pigs were sensitized with an acetone extract of the sweater material, by means of the guinea pig maximization test (GPMT). Active ingredients were then separated from the extract, by step-by-step patch test screening of chromatographic fractions in the guinea pigs, and finally analyzed by gas chromatography-mass spectrometry (GC-MS). Although there were 2 allergens with important activity (1 in the fraction eluted from the silica gel column with hexane, and 1 in the methanol fraction), the present study is focussed on the fat-soluble allergens in the hexane fraction. GC-MS analysis revealed that 4 kinds of phosgene (chlorophenyl)hydrazones (PCPHs) were present in the hexane fraction. PCPHs prepared in our laboratory showed strong eliciting activities, not only in the guinea pigs sensitized with the extract, but also in a male volunteer sensitized by exposure to a yellow sweater during irritancy testing. Phosgene (2,5-dichlorophenyl)hydrazone, which was the main component among the PCPHs found in the sweater, sensitized guinea pigs even at the 1 ppm level. From these results, we conclude that PCPHs were one of the allergens responsible for the cases.  相似文献   
66.
Early enteral nutrition is an important part of intensive care therapy concepts. It contributes considerably to reducing secondary infections and improving prognosis. Besides approved standard formulas, special nutritive solutions are available permitting the application of specific nutritive substrates needed in case of organ failure and during phases of critical illness. Targeted application of enteral nutrition can modulate inflammatory reactions, reparation processes, immune responses, and stabilize mucosal barrier function.  相似文献   
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68.
Polymeric drug conjugates are used in cancer therapy and, varying their molecular size and charge, will affect their in vivo transport and extravasation in tumours. Partitioning between tumour vasculature and tumour tissue will be of particular significance in the case of photosensitizer conjugates used in photodynamic therapy, where this partitioning can lead to different therapeutic effects. Poly-l-lysine chlorin e6conjugates (derived from polymers of average Mr 5000 and 25000) were prepared both in a cationic state and by poly-succinylation in an anionic state. A fluorescence scanning laser microscope was used to follow the pharmacokinetics of these conjugates in vivo in an orthotopic rat prostate cancer model obtained with MatLyLu cells. Fluorescence was excited with the 454-528 nm group of lines of an argon laser and a 570 nm long pass filter used to isolate the emission. Results showed that the conjugates initially bound to the walls of the vasculature, before extravasating into the tissue, and eventually increasing in fluorescence. The anionic conjugates produced tissue fluorescence faster than the cationic ones, and surprisingly, the larger Mr conjugates produced tissue fluorescence faster than the smaller ones with the same charge. These results are consistent with differences in aggregation state between conjugates.  相似文献   
69.
Summary Coordinated contraction of the ventricle is an important determinant of pump function, which seems to be particularly important in Fontan circulation with one pumping ventricle. We analyzed the synchronism of contraction of the two ventricles in 11 patients with a biventricular heart who had undergone Fontan operation. Curves representing ventricular volume changes in a cardiac cycle measured on angiograms were smoothed and divided into 20 segments. We calculated the number of segments of the same directional volume changes (synchronous changes) between the two ventricles (synchronous ratio). We also calculated the total volume of the two ventricles (the two as one whole ventricle) by adding their volumes in each segment and calculated the ratio (stroke volume ratio) of theaortic stroke volume from the whole ventricle to the sum of stroke volumes of the morphological right and left ventricles. If the two ventricles ejected the blood in a completely synchronous manner, these ratios should be 1.0. In seven patients with synchronous ratios of 0.75 or greater and a stroke volume ratio of greater than 0.95, the cardiac index was 3.2 ± 0.31/min/m2, the maximum total volume (corresponding to end-diastolic volume) was 106 ± 45% normal, and the ejection fraction was 0.44 ± 0.10. In four patients with ratios of less than 0.70 and 0.95, respectively, the parameters were 2.4 ± 0.5 (P < 0.05), 193 ± 92%, and 0.33 ± 0.08, respectively. The synchronous ratio was inversely correlated with cardiac output. In conclusion, synchronism of the cardiac cycle of the two ventricles affects Fontan circulation in patients with a biventricular heart.  相似文献   
70.
Little is known about the growth potential of pulmonary stenotic lesions after balloon angioplasty (BA) in patients after the arterial switch operation. The aim of this study was to evaluate the growth potential of pulmonary stenotic lesions after BA and assess the midterm results of BA for pulmonary artery stenosis after the arterial switch operation. Thirty-seven patients who had undergone 52 procedures had repeat catheterization at a median of 43 years (range 1.2 to 9.3 ys) after BA. To adjust growth-related changes in the size of the pulmonary artery, the stenotic diameter was expressed as a percentage of normal (%N). An immediate increase of 63 +/- 45% in the stenotic diameter and a reduction of 51 +/- 33% in the pressure gradient occurred across the stenotic lesions after BA. The right ventricular-aortic systolic pressure ratio decreased from 0.67 +/- 0.24 to 0.51 +/- 0.12 after BA (p <0.0001). Compared with immediate data after BA, there was no significant change in the growth-adjusted diameter of the stenotic lesions (68 +/- 26 %N after BA vs 65 +/- 25 %N at follow-up, p = 0.08), and the pressure gradient (16 +/- 13 mm Hg after BA vs 20 +/- 21 mm Hg at follow-up, p = 0.10). The ventricular-aortic systolic pressure ratio also did not change (0.51 +/- 0.12 after BA vs 0.50 +/- 0.21 at follow-up, p = 0.57). Restenosis occurred in 3 of 26 vessels (12%) after successful BA in which the diameter increased >50% after BA. Our data suggest that pulmonary stenotic lesions after BA develop with age in growing children after the arterial switch operation, and the efficacy of the BA may be long lasting.  相似文献   
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