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PURPOSE: To allow the longitudinal investigation of molecular events associated with the progression of human hepatocellular carcinoma (HCC), we sought to develop a murine model by orthotopic implantation of tumor fragments obtained from patients diagnosed at early stage. EXPERIMENTAL DESIGN: Tumor pieces (2 x 2 mm) were implanted on the liver surface of nu/nu mice. After xenograft growing, subsequent passages were performed to achieve long-term implant viability. Isolation of tumoral hepatocytes was done to establish new cell lines. HCC characteristics, proliferation rate, apoptotic index (terminal deoxynucleotidyl transferase-mediated nick end labeling), and expression of cell-cycle regulators (cyclins E and A, p21(Cip1), p27(Kip1), p16(INK4a), pRb, and p53) were assessed by Western Blot and immunohistochemistry, to correlate them with tumor progression. RESULTS: Five (50%) of the 10 primary HCCs resulted in small slow-growing liver implants. Three of them are viable after 48 months, whereas the remaining two survived for 15 and 13 months. Xenografts throughout passages exhibited a more aggressive phenotype with a poorer degree of differentiation, intense proliferation, moderate apoptosis, cell-cycle deregulation, p53 alterations, microvascular invasion, and dissemination. In one single passage, we observed critical growth delay, which was associated with significant p27(kip1) overexpression. We established the anchor-free growing BCLC-9 cell line from one xenograft. This has gains of chromosomes 7, 5p, 6q, and 9q, is hepatitis B virus-DNA positive, does not secrete alpha-fetoprotein, and has TP53 missense mutations in codons 192 and 242. CONCLUSIONS: The orthotopic implantation of early HCC fragments in nude mice provides a useful model to investigate the mechanisms of human HCC evolution and to establish new cell lines.  相似文献   
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The phenotypes of the temporomandibular joint (TMJ) disc cells range from fibroblasts to chondrocytes. There are relatively few reported studies using transmission electron microscopy (TEM) to determine the ultrastructural features of these cells. It was hypothesized that at least a subpopulation of TMJ stromal cells could be represented by the telocytes, cells with telopodes. In this regard a TEM study was performed on rat TMJ samples. Collagen-embedded networks were found built-up by cells with telopodes with subplasmalemmal caveolae, moderate content in matrix secretory organelles and well-represented intermediate filaments. Appositions of cell bodies were found. Prolongations of such cells were closely related to nerves and microvessels. Our study indicates that the TMJ disc attachment seems equipped with telocytes capable of stromal signaling. However, further studies are needed to assess whether the telocytes belong to a renewed cell population derived from circulating precursors.  相似文献   
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ObjectiveOur objective was to describe the variability in the management of spondyloarthritis (SA) in Spain in terms of healthcare resources and their use.MethodsA review of 1168 medical files of patients seen in randomly selected Spanish hospital rheumatology departments. We analyzed demographic variables and variables related to the consumption of health resources.ResultsThe total number of visits to rheumatology were 5,908 with a rate of 254 visits/100 patient-years. The total number of visits to rheumatology specialty nurses was 775, with a rate of 39 visits/100 patient-years, and there were 446 hospitalizations, representing a rate of 22 per 100 patient-years. The number of admissions due to SA was 89, with a rate of 18 admissions/100 patient-years. Total visits to other specialists was 4,307 with a rate of 200/100 patient-years. The total number of orthopedic surgeries was 41, which leads to a rate of 1.8 surgeries/100 patient-years.ConclusionsThe data regarding visits to the rheumatologist and prosthetic surgery of patients with in Spain is similar to most studies published in our environment, however, other aspects concerning the use of health resources are different compared to other countries. This data may help to understand and improve organizational aspects of management of SA in Spanish hospitals.  相似文献   
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Increased risk of tuberculosis in patients with rheumatoid arthritis   总被引:6,自引:0,他引:6  
OBJECTIVE: To quantify the risk of tuberculosis (TB) in an unselected sample of patients with rheumatoid arthritis (RA) compared to the risk in the general population. METHODS: The incidence of TB in the general population of Spain was obtained from the National Network of Epidemiological Surveillance reports. The incidence of TB was ascertained from a cohort of 788 patients with RA selected randomly from the registries of 34 participating centers throughout Spain. A patient was considered a TB case only if information about disease symptoms, microorganism identification, and TB treatment were confirmed in the clinical records. The relative risk of TB in RA was calculated by dividing the standardized mean incidence of TB from 1990 to 2000 in the RA cohort by the mean incidence of TB in Spain during the same years. RESULTS: The mean incidence of TB in the general population of Spain from 1990 to 2000 was 23 cases per 100,000. Seven cases of TB were identified in the RA cohort, yielding a mean annual incidence (1990-2000) of 134/100,000 patients. The incidence risk ratio of pulmonary TB in patients with RA compared to the general population is 3.68 (95% CI 2.36-5.92). CONCLUSION: We found a 4-fold increased risk of TB infection in patients diagnosed with RA. These results might help to interpret the magnitude of the problem attributable to the introduction of new therapies in RA.  相似文献   
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OBJECTIVE: To evaluate the validity, responsiveness, and predictive value of power Doppler ultrasonography (PDUS) monitoring of response to tumor necrosis factor (TNF) blocking agents in rheumatoid arthritis (RA). METHODS: Three hundred sixty-seven RA patients were prospectively recruited at 25 Spanish centers; complete clinical, laboratory, and PDUS data were obtained on 278 patients. The patients underwent clinical, laboratory, and PDUS assessment at baseline and after 1, 3, 6, and 12 months of anti-TNF treatment, and radiographic assessment of the hands and feet at baseline and 12 months. The Disease Activity Score in 28 joints (DAS28) was recorded at each visit. PDUS examination included 86 intraarticular and periarticular sites in 28 joints. US synovial fluid (SF), synovial hypertrophy (SH), and PD signal were scored in all synovial sites. US count and index for SF, SH, and PD signal were obtained. Sensitivity to change of the PDUS variables was assessed by estimating the smallest detectable difference (SDD) from the intraobserver variability. RESULTS: A significant parallel improvement in DAS28 and PDUS parameters was found at followup assessment (P < 0.0005 for within-subject between-visit changes). The SDD for PDUS parameters was lower than the mean changes throughout followup. Time-integrated values of US joint count for PD signal and rheumatoid factor (RF) showed predictive value in relation to progression of radiographic erosion (R = 0.64), and time-integrated values of US joint count for PD signal, RF, and erythrocyte sedimentation rate were predictors of progression of the total radiographic score (R = 0.59). CONCLUSION: These findings indicate that PDUS is a valid method for monitoring response to anti-TNF therapy in RA; results obtained by PDUS are reproducible and sensitive to change. PDUS findings may have predictive value in relation to radiologic outcome.  相似文献   
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OBJECTIVE: To investigate the impact of official recommendations regarding the management of latent tuberculosis (TB) infection on the rate of active TB in patients receiving treatment with tumor necrosis factor (TNF) antagonists. METHODS: Data on active TB rates and on screening and treatment of latent TB infection were extracted from the BIOBADASER (Spanish Society of Rheumatology Database on Biologic Products), a registry of patients with rheumatic conditions treated with TNF antagonists. The rates of active TB among the BIOBADASER patients were compared with those in the background Spanish population, and BIOBADASER patients with rheumatoid arthritis (RA) were compared with a cohort of RA patients from the EMECAR (Morbidity and Clinical Expression of Rheumatoid Arthritis) study who were not treated with TNF antagonists and were followed up for 5 years. RESULTS: Active TB developed in 34 patients, of whom 32 started taking TNF antagonists prior to the official recommendations on latent TB infection (pre-OR) and 2 began treatment after the recommendations were issued (post-OR). All cases of TB occurred during treatment with infliximab, and 28 of these patients had RA. Pre-OR, the active TB rate in BIOBADASER patients was 20.9-fold higher than in the background Spanish population, while RA patients in the BIOBADASER had rates 22.6- and 6.2-fold higher than the background and EMECAR populations, respectively. Post-OR, 324 patients with a tuberculin skin test result > or =5 mm and/or chest radiograph findings suggestive of past TB were treated for 9 months with isoniazid (INH). Post-OR, active TB rates among the BIOBADASER patients decreased by 78% (incidence risk ratio [IRR] 0.22, 95% confidence interval [95% CI] 0.03-0.88; P = 0.008), while among RA patients in the BIOBADASER, the rate dropped by 83% and reached the EMECAR rate (IRR 1.0, 95% CI 0.02-8.2). There were no INH treatment-related hospitalizations or deaths. CONCLUSION: Strategies to treat latent TB infection that are tailored to the at-risk population can effectively and safely lessen the likelihood of active TB in patients treated with TNF antagonists.  相似文献   
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