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11.
Jeffrey M. Vinocur Jeremiah S. Menk John Connett James H. Moller Lazaros K. Kochilas 《Pediatric cardiology》2013,34(5):1226-1236
Mortality after pediatric cardiac surgery varies among centers. Previous research suggests that surgical volume is an important predictor of this variation. This report characterizes the relative contribution of patient factors, center surgical volume, and a volume-independent center effect on early postoperative mortality in a retrospective cohort study of North American centers in the Pediatric Cardiac Care Consortium (up to 500 cases/center/year). From 1982 to 2007, 49 centers reported 109,475 operations, 85,023 of which were analyzed using hierarchical multivariate logistic regression analysis. Patient characteristics varied significantly among the centers. The adjusted odds ratio (OR) for mortality decreased more than 10-fold during the study period (1982 vs. 2007: OR, 12.27, 95 % confidence interval [CI], 8.52–17.66; p < 0.0001). Surgical volume was associated inversely with odds of death (additional 100 cases/year: OR, 0.84; 95 % CI, 0.78–0.90; p < 0.0001). In the analysis of interactions, this effect was fairly consistent across age groups, risk categories (except the lowest), and time periods. However, a volume-independent center effect contributed substantially more to the risk model than did the volume. The Risk Adjusted Classification for Congenital Heart Surgery, version 1 (RACHS-1) risk category remains the strongest predictor of postoperative mortality through the 25-year study period. In conclusion, center-specific variation exists but is only partially explained by operative volume. Low-risk operations are safely performed at centers in all volume categories, whereas regionalization or other quality improvement strategies appear to be warranted for moderate- and high-risk operations. Potentially preventable mortality occurs at centers in all volume categories studied, so referral or regionalization strategies must target centers by observed outcomes rather than assume that volume predicts quality. 相似文献
12.
Maria Papaioannou Georgia Pitsiou Katerina Manika Paschalina Kontou Pavlos Zarogoulidis Lazaros Sichletidis 《COPD》2014,11(5):489-495
The COPD assessment test (CAT) is a short questionnaire designed to assess the impairment in health status of COPD patients. We aimed to determine the change of the CAT in COPD patients after 1 year of treatment and test the association between the score and clinical and lung function variables. Methods A cohort of 111 newly diagnosed COPD patients in primary care was evaluated at baseline and one year after the implementation of the recommended treatment according to the Global Initiative for the management of COPD (GOLD). Results Most of the patients (82%) were diagnosed with mild to moderate airflow limitation (mean FEV1 72 ± 21.5% predicted) and the CAT score increased in proportion with the GOLD stage of severity. The CAT significantly correlated with the number of exacerbations, visits to general practitioners and days of hospitalization both at the beginning and at 1 year follow-up. A strong negative correlation between the CAT score and FEV1 predicted was also observed. The CAT was responsive to the application of treatment with a significant improvement in the mean score (95% confidence interval) following 12 months of treatment by –2.4 (–2.9, –1.9) despite the small decline in lung function indices. The number of exacerbations in the preceding year and FEV1 were independent predictors of the CAT score in the general linear model. Conclusion The CAT questionnaire may serve as a simple, measurable tool complementary to spirometry in the assessment of severity and of response to treatment in unselected COPD patients in primary care. 相似文献
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Kalogerou A Gelou E Mountantonakis S Settas L Zafiriou E Sakkas L 《Annals of the rheumatic diseases》2005,64(8):1233-1235
OBJECTIVES: To determine if T cells in skin lesions in systemic sclerosis (SSc) express the early activation antigen CD69 that participates in cell-cell interactions. METHODS: Skin biopsy specimens from 17 patients with SSc were analysed by immunohistochemistry using the indirect peroxidase method and monoclonal antibodies for CD3 (T cell marker), CD69 (early T cell activation marker), and CD68 (macrophage marker). RESULTS: Mononuclear cells, containing mostly T cells and macrophages, were increased in SSc skin lesions and were present in perivascular areas. CD69 was expressed in these mononuclear cells. There was no correlation between the number of CD3+, CD69+, or CD68+ cells and the Rodnan skin score or disease duration. CONCLUSIONS: The expression of early T cell activation antigen CD69 in skin lesions suggests that T cells may actively participate in cell-cell contact with fibroblasts to promote fibrosis. 相似文献
16.
Logan G. Spector Jeremiah S. Menk Jessica H. Knight Courtney McCracken Amanda S. Thomas Jeffrey M. Vinocur Matthew E. Oster James D. St Louis James H. Moller Lazaros Kochilas 《Journal of the American College of Cardiology》2018,71(21):2434-2446
Background
Congenital heart surgery has improved the survival of patients with even the most complex defects, but the long-term survival after these procedures has not been fully described.Objectives
The purpose of this study was to evaluate the long-term survival of patients (age <21 years) who were operated on for congenital heart defects (CHDs).Methods
This study used the Pediatric Cardiac Care Consortium data, a U.S.-based, multicenter registry of pediatric cardiac surgery. Survival analysis included 35,998 patients who survived their first congenital heart surgery at <21 years of age and had adequate identifiers for linkage with the National Death Index through 2014. Survival was compared to that in the general population using standardized mortality ratios (SMRs).Results
After a median follow-up of 18 years (645,806 person-years), 3,191 deaths occurred with an overall SMR of 8.3 (95% confidence interval [CI]: 8.0 to 8.7). The 15-year SMR decreased from 12.7 (95% CI: 11.9 to 13.6) in the early era (1982 to 1992) to 10.0 (95% CI: 9.3 to 10.8) in the late era (1998 to 2003). The SMR remained elevated even for mild forms of CHD such as patent ductus arteriosus (SMR 4.5) and atrial septal defects (SMR 4.9). The largest decreases in SMR occurred for patients with transposition of great arteries (early: 11.0 vs. late: 3.8; p < 0.05), complete atrioventricular canal (31.3 vs. 15.3; p < 0.05), and single ventricle (53.7 vs. 31.3; p < 0.05).Conclusions
In this large U.S. cohort, long-term mortality after congenital heart surgery was elevated across all forms of CHD. Survival has improved over time, particularly for severe defects with significant changes in their management strategy, but still lags behind the general population. 相似文献17.
Vlahoyiannis Angelos Karali Eirini Giannaki Christoforos D. Karioti Aggeliki Pappas Aggelos Lavdas Eleftherios Karatzaferi Christina Sakkas Giorgos K. 《Sleep & breathing》2022,26(1):149-156
Sleep and Breathing - To compare physical, psychological, and physiological adaptations between rotating and morning shift health workers using objective and subjective approaches. Forty nurses... 相似文献
18.
Dimitrios P. Bogdanos Daniel S. Smyk Pietro Invernizzi Eirini I. Rigopoulou Miri Blank Lazaros Sakkas Shideh Pouria Yehuda Shoenfeld 《Immunologic research》2013,56(2-3):220-240
We recently introduced the concept of the infectome as a means of studying all infectious factors which contribute to the development of autoimmune disease. It forms the infectious part of the exposome, which collates all environmental factors contributing to the development of disease and studies the sum total of burden which leads to the loss of adaptive mechanisms in the body. These studies complement genome-wide association studies, which establish the genetic predisposition to disease. The infectome is a component which spans the whole life and may begin at the earliest stages right up to the time when the first symptoms manifest, and may thus contribute to the understanding of the pathogenesis of autoimmunity at the prodromal/asymptomatic stages. We provide practical examples and research tools as to how we can investigate disease-specific infectomes, using laboratory approaches employed from projects studying the “immunome” and “microbiome”. It is envisioned that an understanding of the infectome and the environmental factors that affect it will allow for earlier patient-specific intervention by clinicians, through the possible treatment of infectious agents as well as other compounding factors, and hence slowing or preventing disease development. 相似文献
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Andreas Lazaros Chryssafidis Germán Cantón Francesca Chianini Elisabeth A. Innes Ed Hoffmann Madureira Solange Maria Gennari 《Parasitology research》2014,113(4):1521-1528
Neospora caninum is a protozoan parasite known as an important cause of bovine abortion worldwide. Little is currently known about how different strains of N. caninum vary in their pathogenicity. In this study, we compared a Brazilian strain, Nc-Bahia, with the first isolate of this coccidian, Nc-1. Eight cows and seven buffaloes were submitted to fixed-time artificial insemination protocols for a better control of pregnancy. Group 1 was inoculated with Nc-Bahia (n?=?8; five cows and three buffaloes), and Group 2 was inoculated with Nc-1 (n?=?5; two cows and three buffaloes). One nonpregnant female of each species was left uninfected as sentinel controls for potential environmental infection. All inoculated animals received 5?×?108 tachyzoites of N. caninum, by intravenous route, on the 70th day of gestation. Uninfected animals remained seronegative throughout the experiment, indicating no exogenous infection, whereas all inoculated animals became seropositive to N. caninum. In Group 1, abortion was found in only one cow on 42 days postinfection (dpi; frequency of abortion?=?12.5 %), whilst all animals from Group 2 aborted on 35 dpi (frequency of abortion?=?100 %). Parasite DNA was detected by seminested PCR in maternal, foetal and placental tissues, confirming vertical transmission in Groups 1 and 2, although histological lesions had different frequencies and degrees of severity between the groups. There was evidence of lower pathogenicity of Nc-Bahia compared to Nc-1 when used in experimental infection, as it caused fewer abortions, as well as less frequent and milder histological lesions. This was the first time Nc-Bahia has been used for experimental infection. 相似文献