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861.
Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease. Characteristic liver-infiltrating immune cells in portal and periportal areas, hypergammaglobulinemia and typical autoantibodies indicate an ongoing autoimmune reaction against liver self antigens, which lead to irreversible cellular damage and ultimately to severe hepatic failure. A significant part of adult, but not pediatric AIH patients, exhibit concurrent autoimmune diseases, further strengthening the immunological etiology of the disease. Genetic susceptibility to autoimmune hepatitis is strongly associated with HLA-DRB1 alleles. In Caucasian European and North American patients, AIH-1 is associated with the presence of DRB1*0301, DRB3*0101 and DRB1*0401 alleles, while AIH-2 is associated with DRB1*0301 or DRB1*07. In Brazil, the primary susceptibility allele for AIH-1 is DRB1*1301, but a secondary association with DRB1*0301 has also been identified. We looked for additional susceptibility factors in the extended MHC region. We genotyped 107 AIH-1 children and up to 326 healthy subjects for TNFA G-308A, TNFA G-238A, LTA A+252G, LTA A+80C, NFKBIL1 T-63A, BAT1 C-348T, BAT1 G-22C, MICA, and HLA-B polymorphisms. The TNFA-308 A allele was significantly increased in AIH-1 when compared with healthy controls, confirming data from other studies. Linkage disequilibrium analysis was carried out. The ancestral haplotype comprising TNFA-308A, TNFA-238G, LTA+252G, LTA+80C, NFKBIL1-63A, BAT1-348C, BAT1-22C, HLA-B*08, MICA*08 was more common in DRB1*03 positive patients than in controls (40% vs. 14%), showing a seven-fold increased risk for the disease [OR=7.8 (95%CI 2.04-29.9.2, p=0.0021). In contrast, the remaining patients carrying DRB1*03 exhibited varied haplotypes. Finally, a variety of class III haplotypes was also present in HLA-DRB1*13 patients, without a predominant pattern. The most common of the 98 haplotypes present in patients were completely absent in controls. The extended haplotype analysis in this sample of AIH-1 patients highlights not only the genetic diversity present in the Brazilian population, but is also in accordance with the previously documented microdiversity within the MHC region. The present knowledge of AIH suggests that the same or a very similar disease can be induced by yet unknown, but different, triggers followed by presentation on different HLA-DR molecules of the epitopes derived from the corresponding autoantigens, characterizing a much more complex disease than previously thought.  相似文献   
862.
Background:The use of the coronary artery calcium score to aid cardiovascular risk stratification may be a more cost-effective tool than the conventional strategy.Objectives:Evaluation of the cost-effectiveness of the use of the calcium score in therapeutic guidance for primary cardiovascular prevention.Methods:A microsimulation model to assess the clinical and economic consequences of atherosclerotic cardiovascular disease, comparing the prevention strategy using the calcium score and the conventional strategy.Results:The results obtained demonstrated a better cost-effectiveness of the therapeutic strategy guided by the calcium score, by reducing incremental costs and increasing quality-adjusted life years (QALY), which corresponds, in number, to improving the quality of life of the individual.Conclusions:The use of the coronary artery calcium score proved to be more cost-effective than the conventional strategy, both in terms of cost and QALY, in most of the scenarios studied.  相似文献   
863.
An efficient immunological reconstitution construes the pillar for the success of allogeneic haematopoietic cell transplantation (HCT) in haematological disorders. Factors influencing post-transplant immune recovery have been largely investigated across multiple cohorts issuing heterogeneous results. Differences in outcomes in adult and paediatric populations suggest an age-related contribution to post-transplant immune reconstitution; however, it is unclear how recipient and donor age may affect the dynamics of single immune cells. Here, we retrospectively collected and analysed immunological data of 174 patients (58 children and 116 adults) consecutively transplanted for haematological disorders in our centre. We show that trajectories of specific immune cells were strictly dependent on recipient age and pretransplant virus exposure, with the strongest effect seen on T CD4+ and B-cell counterparts, while donor age and transplant platforms had a minimal impact. This mirrored different kinetics of immune reconstitution in adult and paediatric patients, with major divergences in immune cell composition in late post-transplant phases, featuring better survival, relapse-free survival and cumulative incidence of pathogen-specific infections in younger patients. Altogether, these findings underpin the importance of recipient age on post-transplant immune cell recovery and define the basic dynamics of the immune reconstitution in paediatric and adult populations as a benchmark for future studies.  相似文献   
864.
Sleep is essential for the maintenance of health and systemic homeostasis. Decreased sleep time and sleep quality have been associated with a wide range of diseases. To evaluate the effects of obstructive sleep apnea (OSA) and total or selective rapid eye movement (REM) sleep deprivation on male reproductive function, we performed a three-arm parallel study with one pre-defined OSA group and a group of healthy volunteers who were then randomised into total or REM sleep deprivation groups. Questionnaires were completed and overnight polysomnography was undertaken, and blood and sperm samples were collected at the Sleep Institute, São Paulo, Brazil. OSA was diagnosed using questionnaires and polysomnography. Male sexual function was assessed through the questionnaires, blood tests, and semen samples. Data showed an association between OSA and lower circulating levels of total and free testosterone and high-density lipoproteins, as well as a lower proportion of healthy sperm cells and decreased sperm concentration, in comparison to volunteers. Volunteers subjected to either total or REM sleep deprivation had increased circulating levels of thyroid-stimulating hormone, insulin, and higher homeostatic model assessment of insulin resistance (HOMA-IR) values. Both sleep-deprived groups also shown decreased cholesterol, and low-density lipoproteins when compared to their baseline levels, but had no alterations in their spermograms. We observed a reduction in total testosterone following total sleep deprivation, but no effect after REM sleep deprivation. OSA was associated with a hormonal imbalance, which is probably linked with impaired reproductive function and associated comorbidities, such as sleep fragmentation/loss and obesity.  相似文献   
865.
Background: The objective was to determine the prevalence of abnormal cytologic smears in a large population of a Brazilian city. Methods: Retrospective study of cervical cytology results performed at a private laboratory in São Paulo - Brazil. A total of 1,030,482 cytology tests were performed between January 2010 and December 2015. Results: Among the satisfactory cytologies, we observed abnormal results in 8.9% (91,371). Analyzing the proportion of exams with altered results over the years, there was no change in these rates. We observed that the proportion of abnormal exams decreased with increasing age. Atypical squamous cells of undetermined significance, possibly non-neoplastic (ASC-US) cytology was the most common abnormality found in the general population with 73.19%, followed by low-grade intraepithelial lesion (LSIL) with 20.5%; these 2 cytological abnormalities add up to 93.69 % of all abnormal results. There was an increase in ASC-US with advancing age, a decrease in prevalence of LSIL, especially after the age of 30 and high-grade intraepithelial lesion (HSIL) shows two peaks of elevation, respectively in the age groups of 30-39 years and over 70 years. Conclusion: Women under the age of 30 showed a higher prevalence of cytological abnormalities, however most of these changes are low-grade lesions. In older women, cytological abnormalities are largely high-grade lesions, requiring greater care to prevent progression to cancer.  相似文献   
866.
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