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81.
82.
ObjectiveTo assess the lymphatic vessel density (LVD) and lymphangiogenesis in urothelial carcinoma of the bladder (UCB) and to identify predictors of progression in patients treated by transurethral resection (TUR).Materials and methodsOne hundred eleven patients who underwent TUR for UCB were retrospectively included. Lymphatic endothelial cells were stained immunohistochemically [D2-40 (podoplanin) antibody in all samples; Prox-1, LYVE-1, and VEGFR-3 (Flt-4) in subgroups]. LVD was measured in representative intratumoral (ITLVD), peritumoral (PTLVD), and nontumoral (NTLVD) areas using standardized criteria. Double-immunostainings with D2-40/CD-34 were performed to distinguish between blood and lymphatic vessels, and D2-40/Ki-67 stainings were done to detect lymphangiogenesis. Lymph-specific parameters were correlated with pathologic and clinical characteristics. In patients with non-muscle-invasive UCB (n = 76) univariable and multivariable analyses were performed to identify predictors of progression.ResultsThe PTLVD was significantly higher than ITLVD and NTLVD (P < 0.001). Proliferating lymphatic vessels were observed in all specimens assessed with D2-40/Ki-67. Characteristic suburothelial D2-40 positivity was observed in noninvasive pTa tumors. LYVE-1-stainings revealed the existence of tumor-associated macrophages. The presence of intratumoral lymphatic vessels was significantly associated with higher tumor stage, high grade, and sessile growth (all P < 0.001). Muscle-invasive tumors (P = 0.020), higher grade (P = 0.026), the presence of lymphovascular invasion (P < 0.001), and concomitant carcinoma in situ (CIS) (P = 0.020), sessile growth (P = 0.004), and loss of suburothelial D2-40 positivity (P = 0.031) were associated with disease progression in univariable analysis. LVD values in any area were not significantly associated with progression despite detection of proliferating lymphatic vessels. The presence of concomitant CIS was identified as an independent predictor of progression on multivariable analysis (P = 0.041; hazard ratio 4.620).ConclusionsA high peritumoral LVD is present in clinically localized UCB. The presence of intratumoral lymphatic vessels correlates with characteristics of aggressive disease. Lymphangiogenesis occurs; however, the lymph-specific parameters tested in this study cannot be used to predict progression following TUR. The presence of concomitant CIS is an important risk factor for later disease progression in patients with non-muscle-invasive UCB. Our results contribute to the understanding of metastatic tumor spread in UCB.  相似文献   
83.
E.H. Strøm, F.P. Reinholt, K. Midtvedt. JC virus‐associated nephropathy: lack of convincing documentation of the diagnosis.
Transpl Infect Dis 2011: 13: 93–94. All rights reserved  相似文献   
84.
Summary

Planar lipid membranes in the presence of the ion carriers valinomycin or nonactin were irradiated with 14 MeV electrons from a linear accelerator. A large increase of the membrane conductance by up to more than two orders of magnitude was found. The effect is virtually abolished either at high pH, or in the absence of oxygen, or in the presence of the radical scavenger ethanol. A further prerequisite for the effect is the presence of unsaturated fatty acid residues. A kinetic analysis of the carrier transport model based on current-voltage curves and on voltage-jump relaxation experiments was performed as a function of radiation dose. Only the translocation rate constant, kMS, of the charged carrier-ion complex was found to be influenced by irradiation. The effect is interpreted as an increase of the polarity (dielectric constant) of the membrane interior induced by the presence of polar products of lipid peroxidation. A combined action of OH- and HO2-radicals seems to be responsible for the phenomena. At large radiation doses (? 103 Gy) a reduction of the membrane conductance was observed. This is interpreted as an increased microviscosity, possibly caused by cross-linking of fatty acid residues. Ion carriers represent sensitive probes of radiation induced membrane damage.  相似文献   
85.
Advisory committees have cautioned that influenza vaccine-induced antibody declines more rapidly in the elderly, falling below seroprotective levels within 4 months. We conducted a literature review to assess this assertion. The articles that were included in this review reported antibody levels > or =4 months after influenza immunization in persons > or =60 years old, interpretable in the context of annual influenza vaccine-approval criteria (seroprotection/seroconversion) specified by the Committee for Proprietary Medicinal Products (CPMP) for the elderly. The final review included 14 studies; 8 of which reported seroprotection rates. Seroprotection exceeding CPMP criteria was maintained > or =4 months after influenza immunization in all 8 of the studies reporting this for the H3N2 component and in 5 of the 7 studies reporting this for the H1N1 and B components. In determining whether CPMP criteria were met at season's end, primary antibody response appeared to be more relevant than secondary antibody decline. Both studies reporting seroprotection rates that failed CPMP criteria > or =4 months after influenza immunization for each of the H1N1 and B components had also reported failed seroprotection at 1 month after immunization. If initially achieved after immunization, seroprotection rates of 70%-100% were maintained not just at 4 months (2 studies) but also at 5 months (2 studies) and even at >6 months (4 studies), for the H3N2 and H1N1 vaccine components. Seroprotection rates appeared less consistent for the B vaccine component, throughout the postimmunization period. Seroconversion appears to vary substantially and inversely with preimmunization titers but not with age. In 2 of 6 studies reporting seroconversion alone, CPMP criteria were still met at 4 months. In the other 4 studies, the main reason for failure at 4 months was primary failure at 1 month. A total of 6 studies compared antibody persistence by age, and no consistent differences were found on that basis. The historic concern that the influenza vaccine-induced antibody response in the elderly declines more rapidly and below seroprotective levels within 4 months of immunization should be reconsidered.  相似文献   
86.
The coincidence of viral hepatitis and acute pancreatitis is well described. Most of the cases are related to acute hepatitis A or B. Hepatitis E virus (HEV) infections are rare in Europe, and very few reports describe HEV as a causative agent of acute pancreatitis in areas of endemic hepatitis E prevalence. We report a case of acute pancreatitis in the course of acute hepatitis E in a 28-year-old male patient. The majority of reported cases, including our case, show several common epidemiological and clinical features: young age, male predominance, onset of acute pancreatitis at the early stage of acute hepatitis, and favorable outcome. Acute pancreatitis should be considered in acute hepatitis E, especially in young, male patients presenting with severe epigastric pain early in the course of disease. The pancreatitis in these patients usually runs a benign course. The patients should be closely monitored because life-threatening complications have been reported.  相似文献   
87.
The mechanism of gastric mucosal protection by an antiulcer agent, colloidal bismuth subcitrate (CBS), against ethanol-induced injury was investigated using in vivo and in vitro systems. The experiments in vivo were conducted with groups of rats with and without indomethacin pretreatment, and the animals received either a dose of CBS (100 mg/kg) or a vehicle (saline), followed 30 min later by ethanol. In the in vitro studies, gastric mucosa segments were cultured in the presence of CBS, ethanol, or both. The results of in vivo experiments revealed that in the absence of CBS, ethanol caused extensive gastric hemorrhagic lesions which were significantly reduced following CBS pretreatment and this effect of CBS was not prevented by indomethacin. The data obtained with gastric mucosal culture established that in comparison to the controls, ethanol caused a 27% decrease in mucin synthesis, while mucin synthesis in the presence of CBS increased by 48%. The increase in mucin synthesis evoked by CBS was accompanied by the enhanced metabolism of mucosal phosphoinositides, as reflected by a decrease in PI (15%) and PIP2 (30%), and an increase in IP1 (26%) and IP3 (67%). In contrast, ethanol, which exhibited detrimental effect on mucin synthesis, caused a decrease in PIP (35%), IP2 (47%) and IP3 (38%), and an increase in PIP2 (80%), and IP1 (51%). However, when the mucosal culture was carried out in the presence of both CBS and ethanol, the detrimental changes evoked by ethanol on mucin synthesis were prevented, and the phosphoinositide and inositide phosphate distribution patterns were quite similar to those in the mucosa cultured in the presence of CBS only.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
The comparative diagnostic value of IgA anti-endomysium and IgA antigliadin antibodies in adults with histologically confirmed celiac disease is reported. Sera from 144 adult patients (without concurrent dermatitis herpetiformis or IgA deficiency) who underwent small bowel biopsy were analyzed for both IgA anti-endomysium and IgA anti-gliadin antibodies. Nineteen patients (13%) had celiac disease. The presence of IgA antiendomysium antibodies had a sensitivity of 74% and a specificity of 100%. The positive and negative predictive values were 100% and 96%, respectively, and the diagnostic accuracy was 97%. In contrast, IgA anti-gliadin antibodies had positive and negative predictive values of 28% and 96%, respectively, with a diagnostic accuracy of 71%. Based on these data, we suggest that small bowel biopsy is not necessary to diagnose celiac disease in symptomatic adults with IgA antiendomysium antibodies. Due to a negative predictive value of 96%, some symptomatic adults lacking anti-endomysium antibodies will not be correctly diagnosed without small bowel biopsy.  相似文献   
89.
90.
Summary The regulatory effects of pindolol and celiprolol on cardiac -adrenoceptor density were studied in vivo in order to assess the subtype selectivity of their partial agonistic activity (PAA). The substances were continuously administered to rats for 1 week by means of implanted osmotic minipumps. The density of -adrenoceptor subtypes were estimated from ICYP saturation binding experiments performed on cardiac ventricular plasma membranes in the presence of a highly selective antagonist (CGP 20172 A or ICI 118,551). Both antagonists were employed at concentrations as high as to block one subtype only without affecting the complementary subtype. For control purposes, rats were also treated with isoprenaline (0.4 mg/kg/h) and propranolol (0.15 mg/kg/h), or vehicle. Pindolol (0.036 mg/kg/h) and celiprolol (0.36 mg/kg/h) reduced the density of ventricular 2-adrenoceptors by 46% and 23%, respectively, which — in the case of pindolol — was significant when compared to the non-treated controls. Both compounds, however, produced a small, but distinct increase in the number of 1-adrenoceptors by approximately 26%. This finding is in contrast to the propranolol-induced upregulation of both 1- and 2-adrenoceptors by approximately 80%. Since supramaximal doses of each drug were administered, a significant smaller increase of 1-adrenoceptors by pindolol and celiprolol —as compared to the increase produced by propranolol — can be interpreted as evidence for a PAA of pindolol and celiprolol on 1-adrenoceptors as well. Isoprenaline as a full agonist caused a marked loss of of both -adrenoceptor subtypes. Although it exhibits equal affinity at both subtypes the decrease amounted to 80% of the 2- but only to 54% of the 1-adrenoceptors density. This indicates that the down-regulation of cardiac -adrenoceptors in general seems to be more pronounced at the 2-than at the 1-adrenoceptors population. We conclude that the subtype desensitization pattern of agents with intrinsic activity precludes the determination of subtype-selectivity, since 1- and 2-adrenoceptors appear to differ in their sensitivity presumably as a result of subtype specific baseline desensitization produced by endogenous catecholamines.  相似文献   
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