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61.
Immunoreactive corticotropin-releasing factor in rat plasma   总被引:2,自引:0,他引:2  
Immunoreactive ACTH (I-ACTH) levels in the rat anterior pituitary and plasma, and immunoreactive corticotropin-releasing factor (I-CRF) concentrations in the median eminence (ME) and plasma were determined after adrenalectomy and in insulin-induced hypoglycemia. I-CRF was detected in plasma from normal rats (mean +/- SD, 5.6 +/- 0.9 pg/ml; n = 6). Gel filtration chromatography of I-CRF from pooled plasma of these rats revealed a single peak which eluted in the position of authentic rat CRF. I-CRF levels in ME and I-ACTH levels in anterior pituitary decreased immediately after adrenalectomy, then gradually increased to high levels 14 days after surgery. Plasma I-CRF and I-ACTH concentrations increased immediately after surgery, slightly decreased to near the control levels at 24 h, and then increased to high concentrations 14 days after surgery. Plasma and ME I-CRF levels 14 days after adrenalectomy, followed by daily dexamethasone replacement, were almost the same as control levels. In insulin-induced hypoglycemia, plasma I-ACTH and I-CRF concentrations increased and ME I-CRF content decreased at 30 and 60 min. These results suggest that plasma I-CRF levels reflect changes in hypothalamic CRF levels.  相似文献   
62.

Background

The functional SYNTAX score (FSS) has been shown to improve the discrimination for major adverse cardiac events compared with the anatomic SYNTAX score (SS) while reducing interobserver variability. However, evidence supporting the noninvasive FSS in patients with multivessel coronary artery disease (CAD) is scarce.

Objectives

The purpose of this study was to assess the feasibility of and validate the noninvasive FSS derived from coronary computed tomography angiography (CTA) with fractional flow reserve (FFRCT) in patients with 3-vessel CAD.

Methods

The CTA-SS was calculated in patients with 3-vessel CAD included in the SYNTAX II (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery II) study. The noninvasive FSS was determined by including only ischemia-producing lesions (FFRCT ≤0.80). SS derived from different imaging modalities were compared using the Bland-Altman and Passing-Bablok method, and the agreement on the SS tertiles was investigated with Cohen’s Kappa. The risk reclassification was compared between the noninvasive and invasive physiological assessment, and the diagnostic accuracy of FFRCT was assessed by the area under the receiver-operating characteristic curve using instantaneous wave-free ratio as a reference.

Results

The CTA-SS was feasible in 86% of patients (66 of 77), whereas the noninvasive FSS was feasible in 80% (53 of 66). The anatomic SS was overestimated by CTA compared with conventional angiography (27.6 ± 6.4 vs. 25.3 ± 6.9; p < 0.0001) whereas the calculation of the FSS yielded similar results between the noninvasive and invasive imaging modalities (21.6 ± 7.8 vs. 21.2 ± 8.8; p = 0.589). The noninvasive FSS reclassified 30% of patients from the high- and intermediate-SS tertiles to the low-risk tertile, whereas invasive FSS reclassified 23% of patients from the high- and intermediate-SS tertiles to the low-risk tertile. The agreement on the classic SS tertiles based on Kappa statistics was slight for the anatomic SS (Kappa = 0.19) and fair for the FSS (Kappa = 0.32). The diagnostic accuracy of FFRCT to detect functional significant stenosis based on an instantaneous wave-free ratio ≤0.89 revealed an area under the receiver-operating characteristics curve of 0.85 (95% CI: 0.79 to 0.90) with a sensitivity of 95% (95% CI: 89% to 98%), specificity of 61% (95% CI: 48% to 73%), positive predictive value of 81% (95% CI: 76% to 86%), and negative predictive value of 87% (95% CI: 74% to 94%).

Conclusions

Calculation of the noninvasive FSS is feasible and yielded similar results to those obtained with invasive pressure-wire assessment. The agreement on the SYNTAX score tertile classification improved with the inclusion of the functional component from slight to fair agreement. FFRCT has good accuracy in detecting functionally significant lesions in patients with 3-vessel CAD. (A Trial to Evaluate a New Strategy in the Functional Assessment of 3-Vessel Disease Using SYNTAX II Score in Patients Treated With PCI; NCT02015832)  相似文献   
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Predicting the short‐term healing progress of pressure ulcers is important for providing timely and appropriate intervention. Although there are some prediction methods available, these are unsuitable for ulcers with abundant necrotic tissue. We aimed to elucidate the relationship between necrotic tissue alteration and protein distributions on ulcers to establish a new prediction method. Thirty‐eight pressure ulcers were retrospectively analyzed. Protein distributions on necrotic tissue were evaluated by the wound blotting at three levels: marker protein positivity, signal patterns (speckled, heterogeneous, or homogeneous), and the occupation of heterogeneous pattern. Peroxidase, alkaline phosphatase, tumor necrosis factor α, and matrix metalloproteinase‐2 were used as marker proteins. One‐week necrotic tissue alteration was classified as liquefaction or nonliquefaction, and associations with protein distributions were analyzed. The peroxidase positivity was significantly higher in the liquefaction than in the nonliquefaction (p = 0.031). In peroxidase‐positive samples, the proportion of nonliquefaction samples was significantly higher in the heterogeneous pattern (p = 0.029). In the heterogeneous‐patterned samples, the proportion of samples with an occupation values greater than the median value tended to be higher in the nonliquefaction (p = 0.087). There was no significant relationship between liquefaction and other markers. Peroxidase positivity predicts 1‐week liquefaction of necrotic tissue, while a heterogeneous pattern indicates nonliquefaction.  相似文献   
67.
Hydrocellular foam dressing (HCF) absorbs excessive wound fluid, which contains various cytokines and growth factors, and ensures a moist environment to promote wound healing. However, the molecular mechanisms underlying the wound fluid component changes induced by HCF are poorly understood. In the present study, we examined the effect of HCF on wound healing and the associated regulatory mechanisms in relation to variations in cytokine levels in the wound fluid. We created full‐thickness wounds on the dorsolateral skin of rats and collected the resulting wound fluid samples. HCF was immersed in a plate containing the wound fluids. HCF was then removed and the excess wound fluid remaining in the plate was examined by cytokine array and enzyme‐linked immunosorbent assay. We also used a rat model and human dermal fibroblast cultures to examine the effect of wound fluid component changes during the wound healing process. Upon treatment with HCF, leptin levels were upregulated in the wound fluid. Fibroblast proliferation was enhanced and the effect was suppressed in the presence of leptin antagonist. In our in vivo model, HCF increased wound contraction compared with film dressings and this positive effect of HCF was suppressed by addition of leptin antagonist. Our results suggest that dermal fibroblast proliferation is upregulated by HCF due to increased leptin level at the wound surface, and these effects promote wound healing. We believe that the present study contributes to furthering the understanding of the mechanisms underlying the effects of HCF‐induced wound healing.  相似文献   
68.
Tumor necrosis factor-alpha (TNF-alpha) is considered to be 1 of the factors that induce vasculitis, including coronary artery aneurysm (CA), in Kawasaki disease (KD), because the blood concentration of TNF-alpha is higher in patients with CA compared with those without. Therefore, an anti-TNF-alphaagent (infliximab) was administered to a 1-month-old girl with refractory KD complicated by CA and subsequently, the CA improved and KD was controlled without complications 20 months after the onset.  相似文献   
69.
Abstract:   Pulmonary surfactant (PS) is a mixture of several lipids (mainly phosphatidylcholine; PC) and four apoproteins (A, B, C and D). The classical hypothesis of PS transport suggests that PS is synthesized in the endoplasmic reticulum and transported to the lamellar body (LB) via the Golgi apparatus. However, recent studies have raised questions regarding this single route. This study examined, independently, the intracellular trafficking route of three different components of PS, that is, PC, SP-A and SP-B. Alveolar type II cells were isolated from Sprague–Dawley rats or Japanese white rabbits. The cells were cultured with either [3H]choline or [35S]methionine/cysteine with or without brefeldin A, which disassembles the Golgi apparatus. LB was purified from disintegrated cells with sucrose density gradient centrifugation. [3H]PC was extracted from radiolabeled media, cells, and the LB fraction with Bligh–Dyer's method. [35S]SP-A or [35S]SP-B was immunoprecipitated from each sample with a specific antibody. [3H]PC was transported and stored to the LB via a Golgi-independent pathway. [35S]SP-A was transported to the Golgi apparatus, underwent glycosylation, and was then constitutively secreted. The secreted [35S]SP-A was re-uptaken into the LB. [35S]SP-B was transported and stored to the LB via the Golgi-dependent pathway. These results indicate that, rather than a single route, surfactant components take different pathways to reside in the LB. These different pathways may reflect the different nature and role of each surfactant component such as surface tension-lowering activity and innate host defense.  相似文献   
70.
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