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131.
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Objectives

The aim of the present study was to evaluate whether extracellular volume fraction (ECV) can reliably inform on the extent of diffuse fibrosis in the simultaneous presence of myocardial inflammation, which has not been verified to date.

Background

Diffuse myocardial fibrosis is associated with unfavorable outcome in patients with cardiomyopathy, and is of prognostic relevance. Assessment of ECV bears promise for being a noninvasive surrogate parameter, but it may be altered by other pathologies.

Methods

In this prospective study, 107 consecutive patients with clinical suspicion of inflammatory cardiomyopathy were included. All patients underwent left ventricular (LV) endomyocardial biopsy (EMB) and cardiac magnetic resonance imaging on a 1.5-T scanner. T1 mapping was obtained with the modified Look-Locker inversion recovery sequence, and ECV was calculated.

Results

Myocardial inflammation was present in 66 patients. Patients with and without inflammation were of similar age and had comparable LV ejection fraction (37 ± 17% vs. 36 ± 18%; p = 0.9) and symptom duration (median 14 days [interquartile range: 5 to 36 days] vs. median 14 days [interquartile range: 7 to 30 days]; p = 0.73). Although LV collagen volume percentage was comparable between groups (inflammation 12.3 ± 17.8% vs. noninflammation 11.4 ± 7.9%; p = 0.577), ECV was significantly higher in patients with inflammation (0.37 ± 0.06%) than in those without inflammation (0.33 ± 0.08%; p = 0.02). Importantly, ECV adequately estimated the degree of LV fibrosis percentage only in patients without inflammation (r = 0.72; p < 0.0001) and not in those with inflammation (r = 0.24; p = 0.06).

Conclusions

These findings prove the theoretical concept of ECV as an estimate for diffuse myocardial fibrosis, but only in the absence of significant myocardial inflammation. Assuming that various degrees of myocardial inflammation and fibrosis coexist in such a scenario, the measured ECV will reflect a sum of these different pathologies but will not inform solely on the extent of diffuse fibrosis.  相似文献   
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OBJECTIVES: Endoscopic ultrasonography (EUS) with the adjunct of EUS-guided fine needle aspiration has become an important diagnostic modality in gastroenterologic oncology. EUS-guided fine needle aspiration mainly relies on cytology; data are scarce that compare cytology and histology. While testing a 22-gauge prototype needle, we prospectively compared the yield for both. METHODS: Forty-two consecutive patients (27 male, 15 female; mean age 59.2 years, range: 17-90 years) were included. In each patient we aimed to make two needle passes, and if the material acquired appeared insufficient macroscopically (no in-room cytopathology was available), further passes were done. The material was sent for cytological and histological assessment. RESULTS: A median number of two passes (range: 2-3) were uneventfully performed for pancreatic lesions (n=30), mediastinal and other lymph nodes/masses (n=8) and various other lesions (n=4) and yielded adequate material for cytology, histology or at least one of the two investigations in 62, 67 and 74% of patients, respectively. No false positive results were found (specificity 100%). Sensitivities were 58.6 and 65.5%, respectively, for cytology and histology alone; combined assessment increased sensitivity to 79.3%. When adjusted values were calculated, based only on those cases with adequate material, sensitivity was 89.5% for cytology and 85.7% for histology, and increased to 100% with combined assessment. CONCLUSION: The new needle achieves sensitivities similar to those previously reported with no significant differences in sensitivity between cytology and histology. More effective tissue acquisition methods must be sought to improve overall results.  相似文献   
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Melatonin (MLT), the pineal gland hormone involved in the regulation of circadian rhythms, shows characteristic diurnal variation. Its physiological role in humans is not clear. Exposure to high altitudes may disrupt the circadian rhythm and lead to various endocrine changes. MLT in humans has not been studied under these conditions. Urinary 6-hydroxy-MLT sulfate (aMT6s) excretion was analyzed during the day (0700-2200 h) and night (2200-0700 h) phases. A cohort of 33 healthy volunteers, aged 19-65 yr, was studied during an ascent to a high altitude in the Himalayas on three occasions (at a lower altitude, at 3400 m, and after reaching maximal altitudes of 5600-6100 m). aMT6s excretion during the daytime remained unchanged during exposure to high altitudes. As expected, nocturnal values were higher than diurnal values at each point in time. However, there was a significant increase in nocturnal MLT excretion after the ascent to high altitudes. Ascent to high altitudes is associated with increased nocturnal excretion of aMT6s. The mechanism and physiological significance of this MLT increase are unclear.  相似文献   
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Objectives and Background: Despite a generally broad use of vascular closure devices (VCDs), it remains unclear whether they can also be used in victims from out-of-hospital cardiac arrest (OHCA) treated with mild therapeutic hypothermia (MTH).Methods: All victims from OHCA who received immediate coronary angiography after OHCA between January 1st 2008 and December 31st 2013 were included in this study. The operator decided to either use a VCD (Angio-Seal™) or manual compression for femoral artery puncture. The decision to induce MTH was based on the clinical circumstances.Results: 76 patients were included in this study, 46 (60.5%) men and 30 (39.5%) women with a mean age of 64.2 ± 12.8 years. VCDs were used in 26 patients (34.2%), and 48 patients (63.2%) were treated with MTH. While there were significantly more overall vascular complications in the group of patients treated with MTH (12.5% versus 0.0%; p=0.05), vascular complications were similar between patients with VCD or manual compression, regardless of whether or not they were treated with MTH.Conclusion: In our study, the overall rate of vascular complications related to coronary angiography was higher in patients treated with mild therapeutic hypothermia, but was not affected by the application of a vascular closure device. Therefore, our data suggest that the use of VCDs in victims from OHCA might be feasible and safe in patients treated with MTH as well, at least if the decision to use them is individually carefully determined.  相似文献   
138.
Pituitary - While reasons for non-adherence in children requiring growth hormone (GH) replacement (GH-Rx) are well researched, few studies have investigated adherence in adult GH deficient...  相似文献   
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