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41.
After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47?±?7 years, 30?% female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5?±?15 years; LVEF 63.5?±?7?%). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3?±?11?%) with higher LV mass relative to age-matched healthy volunteers (114?±?27 vs. 85.8?±?18 g; p?<?0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39?±?0.06 vs. 0.28?±?0.03, p?<?0.0001; τic: 0.12?±?0.08 vs. 0.08?±?0.03, p?<?0.001). ECV was associated with LV mass (r?=?0.74, p?<?0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35?±?0.02 for 0R vs. 0.45?±?0, p?<?0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.  相似文献   
42.
Clinical Rheumatology - Adherence to prescribed medication regimens is fundamental to the improvement and maintenance of the health of patients with rheumatoid arthritis. It is therefore important...  相似文献   
43.
Surfactant protein-A (SP-A) was measured in bronchoalveolar lavage (BAL) samples from ventilated neonates in order to study the concentration of SP-A with regard to: 1) high-frequency oscillatory ventilation (HFOV) vs. conventional mechanical ventilation (CMV); 2) the postnatal course and ontogeny of SP-A; and 3) the correlation with measurements of pulmonary function. Patients on HFOV had markedly lower BAL SP-A concentrations on days 1 and 2 compared to those on CMV, which may indicate influence of mode of ventilation on surfactant metabolism. The SP-A concentrations increased postnatally concurrent with resolution of acute respiratory distress syndrome. Finally, there were only weak correlations between BAL SP-A concentration and dynamic lung compliance and oxygen requirement.  相似文献   
44.
Various indirect indices have been used in human immunodeficiency virus (HIV)-infected individuals to assess insulin resistance, but the validity of these measures has not been rigorously assessed by comparison with physiologic methods of quantifying insulin-mediated glucose uptake (IMGU). We directly measured IMGU in 50 nondiabetic HIV-positive subjects by determining the steady-state plasma glucose (SSPG) concentration in response to a 3-hour continuous infusion of insulin, glucose, and somatostatin. Because steady-state plasma insulin concentrations were similar (approximately 60 microU/mL) in all subjects, the SSPG concentrations provided direct assessments of insulin action. Relationships between SSPG levels and various surrogate measures of IMGU derived from the 75-g oral glucose tolerance test (OGTT) were determined. The indirect measure of IMGU most closely related to SSPG concentrations was the total integrated insulin response to a 75-g glucose load (r=0.78, P<.01), accounting for approximately two thirds of the variability in SSPG (r2=0.61). Other indirect measures of IMGU, including the homeostasis assessment for insulin resistance (HOMA-IR), were also significantly related to SSPG values, but had lower magnitudes of correlation (r=0.43 to 0.61), thereby possessing limited ability to predict SSPG variability (r2=0.18 to 0.37). In conclusion, indirect measures of IMGU need to be applied with caution when evaluating insulin action in HIV-infected patients.  相似文献   
45.
Overlap syndromes between autoimmune hepatitis and both primary biliary cirrhosis and primary sclerosing cholangitis are well described, but overlap between primary biliary cirrhosis and primary sclerosing cholangitis is not recognized. We present two cases of an unusual autoimmune liver disease, both of which included an overlap between primary biliary cirrhosis and primary sclerosing cholangitis, while one had features of all three conditions. The diagnoses were based on clinical, biochemical, serological, histological and cholangiographic findings. The two cases were identified from a consecutive cohort of 261 patients with autoimmune liver disease followed prospectively in secondary care over a 20-year period, which gives perspective to this uncommon overlap syndrome.  相似文献   
46.
Insulin resistance as a predictor of age-related diseases   总被引:13,自引:0,他引:13  
The current study was initiated to evaluate the ability of insulin resistance to predict a variety of age-related diseases. Baseline measurements of insulin resistance and related variables were made between 1988-1995 in 208 apparently healthy, nonobese (body mass index < 30 kg/m2) individuals, who were then evaluated 4-11 yr later (mean +/- SEM = 6.3 +/- 0.2 yr) for the appearance of the following age-related diseases: hypertension, coronary heart disease, stroke, cancer, and type 2 diabetes. The effect of insulin resistance on the development of clinical events was evaluated by dividing the study group into tertiles of insulin resistance at baseline and comparing the events in these 3 groups. Clinical endpoints (n = 40) were identified in 37 individuals (18%) of those evaluated, including 12 with hypertension, 3 with hypertension + type 2 diabetes, 9 with cancer, 7 with coronary heart disease, 4 with stroke, and 2 with type 2 diabetes. Twenty-eight out of the total 40 clinical events were seen in 25 individuals (36%) in the most insulin-resistant tertile, with the other 12 occurring in the group with an intermediate degree of insulin resistance. Furthermore, insulin resistance was an independent predictor of all clinical events, using both multiple logistic regression and Cox's proportional hazards analysis. The fact that an age-related clinical event developed in approximately 1 out of 3 healthy individuals in the upper tertile of insulin resistance at baseline, followed for an average of 6 yr, whereas no clinical events were observed in the most insulin-sensitive tertile, should serve as a strong stimulus to further efforts to define the role of insulin resistance in the genesis of age-related diseases.  相似文献   
47.
48.
Archives of Women's Mental Health - A Correction to this paper has been published: https://doi.org/10.1007/s00737-021-01122-7  相似文献   
49.
Background Drooling is a major morbidity in several neurological diseases. Intraglandular botulinum neurotoxin (BoNT) injections have been used to manage this condition. However, by decreasing salivary flow, BoNT injections may result in an increased risk of caries and other oral adverse effects. In this study, we aimed to assess whether, in patients with drooling, intraglandular BoNT injections are associated with increased dental caries development, modifications on salivary composition (oral pH, buffering capacity and osmolality) and cariogenic bacterial load. Material and Methods We performed a systematic review, searching PubMed, CENTRAL, Web of Science, and Scopus for all experimental and observational studies reporting on adverse effects of intraglandular BoNT injections in patients with drooling. Primary study selection, quality assessment, and data extraction were independently performed by two researchers. No studies were excluded based on their language, publication status or date of publication. Studies’ quality was based on revised Cochrane Risk of Bias tools. Meta-analysis was not performed. Results We retrieved 1025 studies, of which 5 were included. Two studies were two randomized controlled trials and three quasi-experimental studies. None of the included studies found BoNT injections to be associated with dental caries development or with significant reductions in oral pH. One of the included primary studies even observed an increase in salivary buffer capacity. One study found an increase in Lactobacilli counts. As for the risk of bias, two studies were classified as having a critical risk, two as high risk and one as having some concerns. Conclusions Currently, there is no evidence that, in patients with drooling, BoNT injections associate with increased risk of dental caries or disturbances in oral pH or salivary buffering capacity. However, the included primary studies had important limitations and differences in their methodologies. Key words:Neurological diseases, drooling, sialorrhea, botulinum toxin, oral health, caries, saliva.  相似文献   
50.
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