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91.
Cardiac troponin T (cTnT) and troponin I (cTnI) are highly sensitive and specific for detecting myocardial damage even in the presence of skeletal muscle injury. In this study, we assessed whether ultraendurance exercise induced cardiomyocyte injury using plasma cTnT and cTnI measurements, quantitative echocardiographic wall-motion analysis, and ejection fraction measurement in athletes who participated in the Hawaii Ironman Triathlon. Twenty-three athletes (11 men) who completed the triathlon (3.9 km swim, 180.2 km bike, and 42.2 km run) participated in this study. Blood samples were obtained 2 days before and immediately after the triathlon for the determination of cTnT (Enzymun, Roche Diagnostics) and cTnI (Dade Behring) concentrations. Quantitative echocardiographic wall motion analysis and ejection fraction were obtained on 12 of the 23 participants before and immediately after the race. No subject had detectable cTnT or cTnI or abnormal echo score before the race. Following the race, 2 subjects (9%) had marked increases in both cTnT (0.15 and 0.33 microg/L) and cTnI (2.09 and 4.44 microg/L). Four additional subjects (17%) had moderate increases in cTnT (0.04 to 0.05 microg/L) but no detectable cTnI. Race time correlated inversely with cTnT (r = -0.65, p <0.01). Mean change in the number of abnormal echo segments after the race was 6.5 in those with a marked increase in cTnT and cTnI, 2.3 in those with a moderate increase in cTnT, and 1.7 in those with no increase. Ejection fraction decreased by an average of 24% after the race (p <0.002). Thus, ultraendurance exercise may cause myocardial damage as indicated by biochemical cardiac-specific markers and echocardiography. The cellular nature of this damage and whether it is transient or permanent is unclear at present.  相似文献   
92.
OBJECTIVE: Leptin, an adipocyte-derived protein product of the obesity (ob) gene, is a multifunctional polypeptide associated with the development of obesity-related disorders in humans. There is considerable inter-individual variation in plasma leptin even among subjects with comparable obesity levels, which suggests that factors other than adipose mass may be involved in the regulation of leptin expression and/or production. The purpose of this study was to evaluate the potential role of glycemic status and adipose-derived cytokines in regulating plasma leptin levels among normal and overweight men. DESIGN: Cross-sectional study. SUBJECTS AND MEASUREMENTS: We measured plasma leptin, insulin, c-peptide and plasma soluble tumor necrosis factor receptor (sTNF-R) concentrations in 178 men. The subjects were selected from the Health Professionals Follow-up Study (HPFS), and aged 47-64 y in 1994, were free of cardiovascular disease, diabetes mellitus, malignant neoplasms, and had provided a fasting blood sample and a detailed lifestyle questionnaire. RESULTS: Men in the highest quintile of plasma leptin (mean = 12.7 ng/ml) weighed more, were less physically active and had higher circulating insulin, c-peptide, sTNF-R1 and sTNF-R2 concentrations than men in the lowest quintile (mean = 2.8 ng/ml). We found a significant correlation between plasma insulin, c-peptide, glycosylated hemoglobin (HbA1c), and sTNF-R1 on leptin concentrations (with Spearman correlation coefficients ranging from 0.17 to 0.48 and all P < 0.05). Only HbA1c and sTNF-R1 were independently and positively associated with plasma leptin after further adjusting for body mass index and other metabolic parameters of interest. Interestingly, these observed associations were limited to men with a BMI > or = 25 kg/m2. CONCLUSION: Our results suggest that glucose homeostasis and the activity of the TNF system may modulate leptin secretion and production among overweight men. Glucose homeostasis and TNF-alpha is important in metabolic disorders related to hyperleptinemia.  相似文献   
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94.
We evaluated the association of plasma insulin and other markers of insulin and glucose control with subsequent colorectal cancer. Incident colon (n = 132) and rectal (n = 41) cancer cases and matched controls (n = 346) were identified between baseline in 1989 and 2000 among participants in a community-based cohort in Washington County, Maryland. Circulating markers of insulin and glucose control were measured in baseline blood samples. Body mass index (BMI) and use of medications to treat diabetes mellitus were self-reported at baseline. Conditional logistic regression was used to estimate matched odds ratios (ORs). Compared with the lowest fourth, participants with insulin concentrations in the highest fourth were not at an increased risk of colorectal cancer [OR, 0.78; 95% confidence interval (CI), 0.45-1.35; P(trend) = 0.24]. Similarly, no associations were observed for the ratio of total cholesterol:HDL-cholesterol, triglycerides, and insulin-like growth factor binding protein 1. However, those in the highest fourth of glycosylated hemoglobin (HbA(1c)) level had a slightly increased risk of colorectal cancer (OR, 1.57; 95% CI, 0.94-2.60; P(trend) = 0.02). The OR of colorectal cancer was 1.70 (95% CI, 1.01-2.86; P(trend) = 0.08) comparing BMI >/=30 kg/m(2) to <25 kg/m(2). The OR of colorectal cancer was 2.43 (95% CI, 1.10-5.38) for the use of medications to treat diabetes. The associations of higher HbA(1c), higher BMI, and the use of medications to treat diabetes, with colorectal cancer lend support to the hypothesis that perturbations in insulin and glucose control may influence colorectal carcinogenesis. It is possible that HbA(1c), BMI, and the use of medications to treat diabetes, as a surrogate for protracted or severe type 2 diabetes mellitus, may have been better time-averaged indicators of hyperinsulinemia and hyperglycemia than the plasma markers that were measured once prediagnostically in a nonfasting population.  相似文献   
95.

Background  

Metabolic syndrome components have been associated with colorectal cancer in several studies; however, evidence for colorectal adenomas is limited. Thus, we evaluated the association between markers of the metabolic syndrome with colorectal adenoma development in a nested case–control study.  相似文献   
96.
Branching enzyme activity was assayed in muscle, peripheral nerve, and leukocytes from 2 Ashkenazi-Jewish patients with adult polyglucosan body disease and 1 African-American and 3 Caucasian patients with the same clinical and pathological features. Branching enzyme activity was normal in the muscle specimens from both Jewish and non-Jewish patients. However, the activity was markedly decreased not only in the leukocytes from the 2 Jewish patients (confirming previous findings), but also in peripheral nerve specimens, whereas it was normal in nerve tissue and leukocytes from all non-Jewish patients. These data confirm a branching enzyme deficiency in a subgroup of patients with adult polyglucosan body disease, and show that the defect is tissue-specific, suggesting that adult polyglucosan body disease has more than one biochemical basis.  相似文献   
97.
OBJECTIVE: The authors examined the rate of response to the combination of nortriptyline and interpersonal psychotherapy for acute and continuation treatment of elderly patients with recurrent major depression. METHOD: The subjects were 73 elderly patients, 61 of whom completed treatment. Nortriptyline steady-state blood levels were maintained at 80-120 ng/ml, and interpersonal psychotherapy was administered weekly for 9.1 weeks (medium) of acute therapy and was decreased from biweekly to triweekly during 16 weeks of continuation therapy. During acute treatment nonresponding patients also received brief adjunctive pharmacotherapy with lithium or perphenazine. RESULTS: Of the 61 subjects given adequate trials of nortriptyline and interpersonal psychotherapy, 48 (78.7%) achieved full remission (Hamilton depression rating of 10 or lower over 16 weeks of continuation therapy), 10 patients (16.4%) did not respond (Hamilton rating never below 15), and three achieved only partial remission (Hamilton rating of 11-14). Early versus late onset was not associated with a difference in response rate. During the placebo-controlled, double-blind transition to maintenance therapy, 19 (76.0%) of the 25 patients randomly assigned to placebo maintenance conditions showed continued recovery and six relapsed. None of the 24 patients assigned to nortriptyline conditions relapsed. CONCLUSIONS: Use of nortriptyline plus interpersonal psychotherapy for 9.1 weeks (median) of acute and 16 weeks of continuation therapy appears to be associated with good response and relatively low attrition but about a 25% chance of relapse during double-blind discontinuation of nortriptyline. These data require confirmation in a controlled clinical trial of acute and continuation therapy.  相似文献   
98.
99.
Two patients with thoracic manifestations of hydatid disease (HD) are discussed; one patient had recurrent HD of the chest wall and the other, intrapulmonary HD after rupture and intrathoracic extension of an infradiaphragmatic cyst. At magnetic resonance (MR) imaging the manifestations of HD in the thorax are similar to previously reported MR findings in HD in the liver. The presence of a low signal intensity rim on T2 weighted images representing the cyst wall was confirmed. On T1 weighted images cysts with heterogeneous low and intermediate signal intensity contents and a relatively high signal intensity wall were seen. 'Folded parasitic membranes' previously not described on MR were noted. Daughter cysts may have a low or high signal intensity depending on contents. Reactive changes in the lung may be quite marked compared with the liver, due to reaction to the parasite or simply because the lung is more easily compressed leading to secondary atelectasis.  相似文献   
100.
Little is known about hearing impairment in patients after organ transplantation. We conducted a single-center study to evaluate hearing impairment in patients after orthotopic liver transplantation (OLT). A questionnaire was sent to 695 adult patients after OLT to assess characteristics and course of auditory impairment. Risk factors such as ototoxic drugs were taken into consideration. Clinical follow-up, including immunosuppressive therapy, was analyzed in detail. The questionnaire was completed by 521 patients (75%). Hearing impairment was reported by 184 patients (35%). A total of 43 patients (8%) suffered from hearing abnormalities prior to OLT. The remaining 141 patients (27%) developed hearing impairment after transplantation. Main problems were hearing loss (52%), tinnitus (38%), and otalgia (30%). There was no association of post-OLT hearing disorders with age or known risk factors. In 43% of patients, onset of hearing impairment was within 2 yr post-OLT. Hearing loss was positively associated with tacrolimus immunosuppression in univariate (P < 0.05) and multivariate analysis (P < 0.02). Patients using a hearing aid received tacrolimus more frequently than cyclosporine (P < 0.05). In conclusion, subjective hearing impairment is frequent in patients after OLT and contributes to post-OLT morbidity. Calcineurin inhibitor-related neurotoxicity appears as a possible mechanism. Further prospective investigations with objective hearing tests are necessary to confirm these results and to evaluate the role of immunosuppression.  相似文献   
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