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101.
Factors secreted by the heart, referred to as "cardiokines," have diverse actions in the maintenance of cardiac homeostasis and remodeling. Follistatin-like 1 (Fstl1) is a secreted glycoprotein expressed in the adult heart and is induced in response to injurious conditions that promote myocardial hypertrophy and heart failure. The aim of this study was to investigate the role of cardiac Fstl1 in the remodeling response to pressure overload. Cardiac myocyte-specific Fstl1-KO mice were constructed and subjected to pressure overload induced by transverse aortic constriction (TAC). Although Fstl1-KO mice displayed no detectable baseline phenotype, TAC led to enhanced cardiac hypertrophic growth and a pronounced loss in ventricular performance by 4 wk compared with control mice. Conversely, mice that acutely or chronically overexpressed Fstl1 were resistant to pressure overload-induced hypertrophy and cardiac failure. Fstl1-deficient mice displayed a reduction in TAC-induced AMP-activated protein kinase (AMPK) activation in heart, whereas Fstl1 overexpression led to increased myocardial AMPK activation under these conditions. In cultured neonatal cardiomyocytes, administration of Fstl1 promoted AMPK activation and antagonized phenylephrine-induced hypertrophy. Inhibition of AMPK attenuated the antihypertrophic effect of Fstl1 treatment. These results document that cardiac Fstl1 functions as an autocrine/paracrine regulatory factor that antagonizes myocyte hypertrophic growth and the loss of ventricular performance in response to pressure overload, possibly through a mechanism involving the activation of the AMPK signaling axis.  相似文献   
102.
ObjectivesThe aim of this study was to investigate sex differences in the prevalence, extent, and association of coronary artery calcium (CAC) and thoracic aorta calcium (TAC) scores with cardiovascular mortality in a population eligible for lung screening.BackgroundCAC and TAC scores derived from chest computed tomography (CT) might be useful biomarkers for individualized cardiovascular disease prevention and could be especially relevant in high-risk populations such as heavy smokers. Therefore, it is important to know the prevalence of arterial calcifications in male and female heavy smokers, and if there are differences in the predictive value calcifications carry.MethodsWe performed a nested case–control study with 5,718 participants of the CT arm of the NLST (National Lung Screening Trial). Prevalence and extent of CAC and TAC were resampled to the full cohort to provide unbiased estimates of the typical calcium burden of male and female heavy smokers. Weighted Cox proportional hazards regression was used to assess differences in the association of CAC and TAC scores with all-cause and cardiovascular mortality.ResultsCAC was substantially more common and more severe in men (prevalence: 81% vs. 60%; median volume: 104 mm³ vs. 12 mm³). Women had CAC comparable to that of men who were 10 years younger. TAC was equally common in men and women, with a tendency to be more pronounced in women (prevalence: 92% vs. 93%; median volume: 388 mm³ vs. 404 mm³). Both types of calcification were associated with increased cardiovascular and all-cause mortality. TAC scores improved the prediction of coronary heart disease mortality over CAC in men, but not in women. In both sexes, TAC, but not CAC, was associated with cardiovascular mortality other than coronary heart disease.ConclusionsCAC develops later in women, whereas TAC develops equally in both sexes. CAC is strongly associated with coronary heart disease, whereas TAC is especially associated with extracardiac vascular mortality in either sex.  相似文献   
103.
OBJECTIVE: To investigate the prevalence of cumulative organ damage in patients with juvenile-onset systemic lupus erythematosus (SLE) and its association with demographic and clinical variables, medication use, and quality of life. METHODS: The occurrence of organ system damage, as measured by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI), was determined for 387 patients consecutively enrolled in pediatric rheumatology centers from Europe, the US, Mexico, and Japan. Risk factors for damage included demographic variables; clinical manifestations at diagnosis; previous corticosteroid, immunosuppressive, and antimalarial therapies; disease activity; and quality of life. RESULTS: Overall, 195 (50.5%) patients had damage within a mean of 5.7 years after disease onset. Renal (21.8%) and neuropsychiatric (15.8%) system involvement were observed most frequently, followed by musculoskeletal (11.7%), ocular (10.9%) and skin (9.6%) system involvement, with a mean SDI score of 1.1. In multivariate models, the occurrence of neuropsychiatric manifestations at diagnosis, a longer disease duration, and a greater number of intravenous cyclophosphamide pulses showed the strongest association with the presence of damage. CONCLUSION: We found evidence of cumulative organ damage, as measured by the SDI, in half of the patients with juvenile-onset SLE. Damage was significantly more likely in patients who had experienced neuropsychiatric manifestations at diagnosis, had a longer disease duration, and had received more intravenous pulses of cyclophosphamide.  相似文献   
104.
Serotonergic drugs may lead to valvular heart disease in humans and more recently also in rats. Although clinical data suggest that dose dependency and reversibility after drug cessation might occur, proof of this is lacking. For that purpose, a total of 106 rats were prospectively enrolled: 22 control animals and 7 groups of 12 rats that received daily subcutaneous serotonin injections (5, 10, 20, 30, 40, 50 and 60 mg/kg respectively) for 12 weeks. At 12 weeks, half of the animals of each group were killed for histological analysis, whereas the remaining rats were further followed (without serotonin injections) for an additional 8 weeks. After 12 weeks of serotonin treatment, aortic and mitral regurgitation (AR, MR) were more frequently observed in the high dose groups (>30 mg/kg) compared to controls. Moreover, aortic and mitral valves were also thicker in the high dose groups compared to controls. After 8 weeks free of serotonin injections, AR and MR were no longer significantly higher than controls. Moreover, aortic and mitral valve thickness had normalized, returning to control levels. In conclusion, this study provides evidence for a dose-dependent valvular toxicity of serotonergic drugs, which appears to be reversible after drug withdrawal.  相似文献   
105.
In this case report we present an elderly patient who was referred to our hospital with recurrent episodes of cholangitis that persisted after placement of five metal stents for a distal common bile duct (CBD) stenosis.All metal stents were endoscopically removed from the CBD by forceps after balloon dilatation of the papilla. A profoundly dilated CBD with sludge and concrements was seen. To ensure adequate bile drainage an enteral metal stent was inserted in the CBD. This case shows that proximally migrated uncovered metal stents in the CBD can be safely removed endoscopically under certain circumstances. We suggest that in the case of a CBD drainage problem due to an extremely dilated CBD, placement of an enteral metal stent in the CBD could be considered, especially in patients who are unfit for surgery.  相似文献   
106.
ObjectivesThe authors sought to evaluate the impact of ischemic burden reduction after chronic total occlusion (CTO) percutaneous coronary intervention (PCI) on long-term prognosis and cardiac symptom relief.BackgroundThe clinical benefit of CTO PCI is questioned.MethodsIn a high-volume CTO PCI center, 212 patients prospectively underwent quantitative [15O]H2O positron emission tomography perfusion imaging before and three months after successful CTO PCI between 2013-2019. Perfusion defects (PD) (in segments) and hyperemic myocardial blood flow (hMBF) (in ml · min?1 · g?1) allocated to CTO areas were related to prognostic outcomes using unadjusted (Kaplan-Meier curves, log-rank test) and risk-adjusted (multivariable Cox regression) analyses. The prognostic endpoint was a composite of all-cause death and nonfatal myocardial infarction.ResultsAfter a median [interquartile range] of 2.8 years [1.8 to 4.3 years], event-free survival was superior in patients with ≥3 versus <3 segment PD reduction (p < 0.01; risk-adjusted p = 0.04; hazard ratio [HR]: 0.34 [95% confidence interval (CI): 0.13 to 0.93]) and with hMBF increase above (Δ≥1.11 ml · min?1 · g?1) versus below the population median (p < 0.01; risk-adjusted p < 0.01; HR: 0.16 [95% CI: 0.05 to 0.54]) after CTO PCI. Furthermore, event-free survival was superior in patients without versus any residual PD (p < 0.01; risk-adjusted p = 0.02; HR: 0.22 [95% CI: 0.06 to 0.76]) or with a residual hMBF level >2.3 versus ≤2.3 ml · min?1 · g?1 (p < 0.01; risk-adjusted p = 0.03; HR: 0.25 [95% CI: 0.07 to 0.91]) at follow-up positron emission tomography. Patients with residual hMBF >2.3 ml · min?1 · g?1 were more frequently free of angina and dyspnea on exertion at long-term follow-up (p = 0.04).ConclusionsPatients with extensive ischemic burden reduction and no residual ischemia after CTO PCI had lower rates of all-cause death and nonfatal myocardial infarction. Long-term cardiac symptom relief was associated with normalization of hMBF levels after CTO PCI.  相似文献   
107.
108.
Summary Meta-iodo-benzylguanidine (MIBG) is an analogue of the neurotransmitter norepinephrine. In its radio-iodinated form, MIBG is clinically used as a tumor-targeted radiopharmaceutical in the diagnosis and treatment of adrenergic tumors. The potential cytotoxicity of the unlabeled drug was tested. MIBG appeared cytotoxic in a large panel of histogenetically different cell lines without preference against tumor cells of neural origin. The cytotoxicity of MIBG was higher than of the related mono-amine precursor, meta-iodo-benzylamine (MIBA). Drugs that block adrenergic receptors and inhibitors of tyrosinase or tyrosine hydroxylase had no effect on the cytostatic properties of MIBG. However, its activity was potentiated by the pharmacological inhibition of catecholamine degradation and by inhibitors of intracellular storage. MIBG had antitumor effects on L1210 leukemia and N1E115 neuroblastoma, grown as subcutaneous tumors in animals treated with MIBG in non-toxic schedules. The observations suggest that MIBG is cytotoxic in its native form and may contribute by this property to the clinical responses obtained with the radiolabeled drug at high concentrations.  相似文献   
109.
In past decades, much effort has been invested in developing therapies for spinal injuries. Lack of standardization of clinical read-out measures, however, makes direct comparison of experimental therapies difficult. Damage and therapeutic effects in vivo are routinely evaluated using rather subjective behavioral tests. Here we show that manganese-enhanced magnetic resonance imaging (MEMRI) can be used to examine the extent of damage following spinal cord injury (SCI) in mice in vivo. Injection of MnCl2 solution into the cerebrospinal fluid leads to manganese uptake into the spinal cord. Furthermore, after injury MEMRI-derived quantitative measures correlate closely with clinical locomotor scores. Improved locomotion due to treating the detrimental effects of SCI with an established therapy (neutralization of CD95Ligand) is reflected in an increase of manganese uptake into the injured spinal cord. Therefore, we demonstrate that MEMRI is a sensitive and objective tool for in vivo visualization and quantification of damage and functional improvement after SCI. Thus, MEMRI can serve as a reproducible surrogate measure of the clinical status of the spinal cord in mice, potentially becoming a standard approach for evaluating experimental therapies.  相似文献   
110.
Previous studies have shown a significant association between reading skills and the performance on visuo-motor tasks. In order to clarify whether reading and writing skills modulate non-linguistic domains, we investigated the performance of two literacy groups on a visuo-motor integration task with non-linguistic stimuli. Twenty-one illiterate participants and twenty matched literate controls were included in the experiment. Subjects were instructed to use the right or the left index finger to point to and touch a randomly presented target on the right or left side of a touch screen. The results showed that the literate subjects were significantly faster in detecting and touching targets on the left compared to the right side of the screen. In contrast, the presentation side did not affect the performance of the illiterate group. These results lend support to the idea that having acquired reading and writing skills, and thus a preferred left-to-right reading direction, influences visual scanning.  相似文献   
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