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1.
Laura Cisneros Maria-Carlota Londo?o Carmen Blasco Ramón Bataller Rosa Miquel Miquel Bruguera Pere Ginès Antoni Rimola 《Liver transplantation》2007,13(7):1017-1027
The pathogenic mechanisms of accelerated graft fibrosis in hepatitis C recurrence after liver transplantation (LT) are not well established. The aim of the study was to assess whether a greater activation of hepatic stellate cells (HSC), the major collagen-producing cells in the liver, can occur in these patients as compared to non-LT patients with chronic hepatitis C. We determined the amount of activated HSC by computer-based morphometric analysis of alpha-smooth muscle actin (alphaSMA)-positive cells and the hepatic TGFbeta(1) expression by immunohistochemistry in 46 LT patients with hepatitis C recurrence, 35 non-LT patients with chronic hepatitis C, and 16 controls. Hepatic alphaSMA and TGFbeta(1) expression was higher in LT patients with hepatitis C recurrence than in controls and was correlated with fibrosis stage and progression rate. No significant difference in alphaSMA and TGFbeta(1) expression was observed between LT and non-LT patients with hepatitis C, with the exception of a higher transforming growth factor beta-1 (TGFbeta(1)) expression in non-LT patients in the early stages of fibrosis. LT patients receiving cyclosporine (CsA) or tacrolimus (FK) had a similar fibrosis progression rate and alphaSMA and TGFbeta(1) expression. In conclusion, the accelerated fibrosis observed in LT patients with hepatitis C recurrence does not seem to be related to a greater amount of activated HSC and TGFbeta(1) expression in the grafts of these patients as compared to non-LT patients with chronic hepatitis C. In LT patients, the amount of activated HSC and TGFbeta(1) expression correlated with fibrosis stage and progression, without any apparent influence of the type of calcineurin inhibitor administered. 相似文献
2.
The main features of central 5-HT1 receptors 总被引:1,自引:0,他引:1
M Hamon L Lanfumey S el Mestikawy C Boni M C Miquel F Bola?os L Schechter H Gozlan 《Neuropsychopharmacology》1990,3(5-6):349-360
The 5-HT1 receptor family comprises five different pharmacologic subtypes, designated 5-HT1A, 5-HT1B, 5-HT1C, 5-HT1D, and 5-HT1E, whose common property is to bind 5-HT with nanomolar affinity. Recent investigations with molecular biology approaches led to the cloning and sequencing of 5-HT1A receptors in the rat and in the human, and of the 5-HT1C receptor in the rat. Although the 5-HT1A and 5-HT1C protein binding subunits exhibit the same structure with seven hydrophobic transmembrane domains, an extracellular N terminal and an intracellular C tail, their respective amino-acid sequences are markedly different. Indeed, a higher degree of sequence homology is found between the 5-HT1C and 5-HT2 receptors than between the former and 5-HT1A receptors, suggesting that the 5-HT1C subtype in fact belongs to the 5-HT2 class of central 5-HT receptors. All other 5-HT1 receptor subtypes are negatively coupled to adenylyl cyclase, whereas the 5-HT1C subtype, like 5-HT2 receptors, is positively coupled to phospholipase C. The respective regional distributions and regulatory properties, as well as pending questions regarding the ultrastructural localization, synthesis, mutual interactions, and axonal flow of 5-HT1 receptor subtypes, are also discussed. 相似文献
3.
Ricardo Mitrani Momo Vasilic August Bruguera 《Practical procedures & aesthetic dentistry》2005,17(1):71-8; quiz 80
Recent scientific and technological developments have allowed the dental team to execute revolutionary restorative treatments that would have once been considered unfeasible. This article describes a restorative alternative for fixed implant-supported reconstructions, consisting of a CAD/CAM-generated framework and CAD/CAM-generated all-ceramic cement-retained restorations. Distinct advantages of this type of restoration include the passive fit of the framework, the ability of the ceramist to fabricate individual restorations independent from the framework, and the delivery of optimal aesthetics. 相似文献
4.
Adrià Arboix Lluis García-Eroles Emili Comes Montserrat Oliveres Miquel Balcells Gustavo Pacheco Cecilia Targa 《European journal of neurology》2003,10(4):429-435
We assessed predictors of spontaneous early neurological recovery after acute ischemic stroke by means of multivariate analysis in a cohort of 1,473 consecutive patients treated at one academic center. At hospital discharge, spontaneous neurological improvement or good outcome was defined as grades 0-2 of the Rankin scale, and poor outcome (no improvement or in-hospital death) as grades 3-5. Spontaneous recovery of neurological deficit at the time of discharge from the hospital was observed in 16% of patients with cerebral infarction (n = 238). Dysarthria-clumsy hand syndrome improved in 44% of patients and was the only variable significantly associated with in-hospital functional recovery in three logistic regression models that in addition to lacunar syndromes, included demographic variables, cardiovascular risk factors, and clinical variables [odds ratio (OR) 2.56], neuroimaging findings (OR 2.48), and outcome data (OR 2.39), respectively. Clinical factors related to severity of infarction available at stroke onset have a predominant influence upon in-hospital outcome and may help clinicians to assess prognosis more accurately. Our work gives a contribution into prognostic factors after acute ischemic stroke. With regard to patterns of stroke, dysarthria-clumsy hand syndrome was a significant predictor of spontaneous in-hospital recovery in ischemic stroke patients. 相似文献
5.
D. L. Ruddle L. S. Yengoyan J. Miquel R. Marcuson J. E. Fleming 《Age (Dordrecht, Netherlands)》1988,11(2):54-58
The effect of propyl gallate (PGL) on life span in Drosophila was investigated. Four groups of flies were supplemented as follows: group 1, no PGL; group 2, no PGL supplement until 28
days followed by 0.3% PGL for remaining life span; group 3, 0.3% PGL from 7 days to 28 days, then none for remaining life
span; and group 4, 0.3% PGL from 7 days until death. In all cases, PGL significantly increased mean life span. The largest
increase in mean life span (34.2%) was in the group receiving PGL for the entire life span (group 4). Increases of 14.6% and
14.7% were measured in groups 2 and 3, respectively. 相似文献
6.
Catarina Eira Jordi Miquel José Vingada Jordi Torres 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(2):119-122
Gongylonema neoplasticum was identified in the oesophagus of 14 wild rabbits (Oryctolagus cuniculus) from Portugal. This is the first record of Gongylonema neoplasticum in a naturally infected lagomorph species in Europe. This paper presents the most relevant measurements of adult worms and
some of their surface features seen by scanning electron microscopy. Epidemiological aspects of G. neoplasticum such as geographical distribution, host spectrum and biological features are discussed. 相似文献
7.
L. Salleras M. Bruguera J. Vidal J. L. Taberner P. Plans J. M. Bayas T. Pumarola M. T. Jimenez de Anta J. Rodes 《European journal of epidemiology》1992,8(5):640-644
The prevalence of hepatitis B markers was determined in a representative sample of the general population of Catalonia (Spain). HBsAg was found in 0.5% of children (less than 15 years of age) and in 1.7% of adults (more than 15 years of age), and anti HBs in 1.6% and 18%, respecitvely. Age-specific prevalence for both markers showed a low risk for hepatitis B before puberty, and a progressive rise since adolescence, suggesting that perinatal transmission and horizontal transmission in children are relatively uncommon in Spain. Prevalence of hepatitis B markers was significantly higher among subjects with low education level, residing in an urban area and born outside Catalonia, but in the stratified analysis, a statistical significant difference was only maintained in the prevalence of HBV markers between those who live in urban and rural areas, and between those who were born outside Catalonia and in Catalonia. These data may be used as a basis for a strategy of hepatitis B prevention in Spain which include universal vaccination of adolescents, passive-active immunization of newborns to HBsAg positive mothers and vaccination of susceptible adults subjects from high-risk groups.Preventive Medicine Unit.Liver Unit.Corresponding author. 相似文献
8.
Among 389 consecutive chronic alcoholics in whom a liver biopsy was performed for diagnostic purposes, nine patients (2.3%) had histological changes of "alcoholic foamy degeneration" (AFD), characterized by numerous small fat droplets in the swollen hepatocytes of the centrilobular area. In five cases, there were non-specific clinical features, while the other four cases presented acute hepatic decompensation with jaundice and a reduced prothrombin activity. Seven patients had high serum lipid concentrations including hypertriglyceridemia and hypercholesterolemia, which improved after withdrawal of alcohol intake. In conclusion, AFD has a broad clinicopathological spectrum including asymptomatic patients and other cases with severe liver decompensation manifested by jaundice and reduced prothrombin activity. AFD is usually associated with hyperlipemia. 相似文献
9.
The role of Serratia marcescens porins in antibiotic resistance 总被引:1,自引:0,他引:1
Ruiz N Montero T Hernandez-Borrell J Viñas M 《Microbial drug resistance (Larchmont, N.Y.)》2003,9(3):257-264
The outer membrane permeability of Serratia marcescens was studied by comparing porin-deficient mutants with their parental strains. Omp1-deficient strains were selected by moxalactam resistance, whereas mutants lacking the Omp2 porin were obtained by experimental infection with the SMP2 phage, whose primary receptor is the Omp2 porin. The role of porins was demonstrated in quinolone accumulation assays, where semiquantitative differences in accumulation were observed. Permeability coefficients to cephaloridine of Omp1 mutants were determined and compared with those of the parental strain. The clinical isolates S. marcescens HCPR1 and 866 showed 30- to 200-fold reduced permeability coefficients when Omp1 porin was absent. 相似文献
10.
Ana Velasco Victor Palomar-Asenjo Laura Ga?an Lluis Catasus Nuria Llecha Angel Panizo Victor Palomar-Garcia Miquel Quer Xavier Matias-Guiu 《Diagnostic molecular pathology》2005,14(2):109-114
The familial paraganglioma syndrome is an autosomal dominant disorder characterized by the presence of carotid body paragangliomas and, less frequently, paragangliomas of the glomus jugulare, glomus vagale, and adrenal pheochromocytomas. Germline mutations of the genes for succinate dehydrogenase subunits D, B, or C (SDHD, SDHB, SDHC) have been identified in some kindreds with familial paraganglioma. In this study, we report the clinicopathologic features of four different kindreds with familial paraganglioma, which were screened for germline mutations in the SDHD gene. DNA was obtained from tumor and normal tissue, as well as from peripheral blood. Mutation analysis was performed by single-strand conformation polymorphism analysis and DNA sequencing. SDHD germline mutations were detected in the affected family members of the four families, as well as in several asymptomatic carriers. An identical mutation in exon 4 of SDHD (334-337delACTG) was identified in two apparently unrelated kindreds. The third family showed a germline mutation in exon 2 (W43X). The mutations present in these three families had been previously described in Spanish families, suggesting a founder effect. The fourth family exhibited a mutation in exon 2 of SDHD (170-171delTT), which had not been previously identified. The affected family members of the four kindreds showed paragangliomas, located in the head and neck region, and all of them were benign. These results confirm that genetic testing of SDHD may be a powerful tool for the identification of the syndrome in patients with multiple or bilateral paragangliomas. 相似文献