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61.
62.

Background

Obesity is characterized by a chronic, low-grade inflammation, and bariatric surgery is proposed as an effective treatment for reducing the obesity-related co-morbidities. Epigenetic modifications could be involved in the metabolic improvement after surgery.

Objective

The main aim of this study was to evaluate whether DNA methylation pattern from genes related to inflammation and insulin response is associated with the metabolic improvement after bariatric surgery in morbidly obese patients and if these changes depend on the surgical procedure.

Setting

University hospital, Spain.

Methods

We studied 60 severely obese patients; 31 underwent Roux-en-Y gastric bypass and 29 underwent laparoscopic sleeve gastrectomy. All patients were examined before and at 6 months after bariatric surgery. DNA methylation profile of genes related to the inflammatory response and insulin sensitivity was measured by pyrosequencing.

Results

The promoter methylation levels of the NFKB1 gene were increased significantly after surgery (2.16 ± .9 versus 2.8 ± 1.03). The decrease in blood pressure, both systolic and diastolic, after surgery was significantly associated with the changes in the promoter methylation levels of the NFKB1 gene (β?=??.513, P?=?.003 and β?=??.543, P?=?.004, respectively). A decrease in inflammation status, measured by high sensitivity C-reactive protein values, was associated with changes in SLC19A1 methylation levels.

Conclusion

Our study shows for the first time an association between NFKB1 methylation levels and blood pressure after bariatric surgery, highlighting the possible function of this gene in the regulation of arterial pressure. Regarding SLC19A1, this gene could position as a potential target linking inflammation and insulin resistance.  相似文献   
63.

Introduction

COPD is a highly prevalent but underdiagnosed disease, due to the limited availability of forced spirometry (FS) in primary care (PC). Microspirometers are inexpensive, easy-to-use devices that can measure FEV6 and FEV1/FEV6, and may help reduce underdiagnosis. The aim of this study was to validate the Piko-6 COPD screening device by demonstrating a good correlation with standard FS.

Methods

FS and Piko-6 determinations were made in 155 patients suspected of having COPD. The correlations, ROC curves, and Youden's index of both methods were compared, taking FS as the gold standard.

Results

FEV1, FVC and FEV6 correlation coefficients and FEV1/FVC and FEV1/FEV6 ratios were 0.87 (CI 0.836–0.909), 0.729 (CI 064–0.795) and 0.947 (95% CI 0.928–0.961), respectively. The ROC curve for FEV1 determined by Piko-6 achieved an area under the curve of 0.86 (95% CI: 0.78–0.92). Youden's index with a cut-off point of 0.70 for FEV1/FEV6 was 0.97.

Conclusions

Piko-6 may be useful for COPD screening in PC. Measurements obtained with this device correlate well with those determined by FS, particularly the FEV1/FEV6 ratio. This, combined with its low cost and ease of use, may contribute to reducing COPD underdiagnosis, although its exact role in the diagnostic process remains to be determined.  相似文献   
64.
65.
The cilium is a signaling platform of the vertebrate cell. It has a critical role in polycystic kidney disease and nephronophthisis. Cilia have been detected on endothelial cells, but the function of these organelles in the vasculature remains incompletely defined. In this study, using genetic and chemical genetic tools in the model organism zebrafish, we reveal an essential role of cilia in developmental vascular integrity. Embryos expressing mutant intraflagellar transport genes, which are essential and specific for cilia biogenesis, displayed increased risk of developmental intracranial hemorrhage, whereas the morphology of the vasculature remained normal. Moreover, cilia were present on endothelial cells in the developing zebrafish vasculature. We further show that the involvement of cilia in vascular integrity is endothelial autonomous, because endothelial-specific re-expression of intraflagellar transport genes in respective mutants rescued the intracranial hemorrhage phenotype. Finally, whereas inhibition of Hedgehog signaling increased the risk of intracranial hemorrhage in ciliary mutants, activation of the pathway rescued this phenotype. In contrast, embryos expressing an inactivating mutation in pkd2, one of two autosomal dominant cystic kidney disease genes, did not show increased risk of developmental intracranial hemorrhage. These results suggest that Hedgehog signaling is a major mechanism for this novel role of endothelial cilia in establishing vascular integrity.  相似文献   
66.
67.
The objective of the study was to assess the use of maximum (Vmax) and final propulsive phase (FPV) bar velocity to predict jump height in the weighted jump squat. FPV was defined as the velocity reached just before bar acceleration was lower than gravity (-9.81 m·s-2). Vertical jump height was calculated from the take-off velocity (Vtake-off) provided by a force platform. Thirty swimmers belonging to the National Slovenian swimming team performed a jump squat incremental loading test, lifting 25%, 50%, 75% and 100% of body weight in a Smith machine. Jump performance was simultaneously monitored using an AMTI portable force platform and a linear velocity transducer attached to the barbell. Simple linear regression was used to estimate jump height from the Vmax and FPV recorded by the linear velocity transducer. Vmax (y = 16.577x - 16.384) was able to explain 93% of jump height variance with a standard error of the estimate of 1.47 cm. FPV (y = 12.828x - 6.504) was able to explain 91% of jump height variance with a standard error of the estimate of 1.66 cm. Despite that both variables resulted to be good predictors, heteroscedasticity in the differences between FPV and Vtake-off was observed (r2 = 0.307), while the differences between Vmax and Vtake-off were homogenously distributed (r2 = 0.071). These results suggest that Vmax is a valid tool for estimating vertical jump height in a loaded jump squat test performed in a Smith machine.

Key points

  • Vertical jump height in the loaded jump squat can be estimated with acceptable precision from the maximum bar velocity recorded by a linear velocity transducer.
  • The relationship between the point at which bar acceleration is less than -9.81 m·s-2 and the real take-off is affected by the velocity of movement.
  • Mean propulsive velocity recorded by a linear velocity transducer does not appear to be optimal to monitor ballistic exercise performance.
Key words: Linear velocity transducer, force platform, jump performance, swimming  相似文献   
68.
Sinusoidal hemangioma, characterized by interconnecting thin-walled vascular spaces, may present papillae/pseudo-papillae and zones that resemble intravascular papillary endothelial hyperplasia (IPEH). Our objectives are to explore the existence of zones in IPEH with sinusoidal hemangioma characteristics, the mechanism of papillary and septa formation in sinusoidal hemangioma and the comparison of this mechanism with that in IPEH. For these purposes, specimens of 4 cases of each entity were selected and studied by serial histologic sections and by immunochemistry and immunofluorescence procedures. The results showed a) zones with characteristics of sinusoidal hemangioma in IPEH cases, b) presence in both entities of papillae with a cover formed by a monolayer of CD34+ and CD31+ endothelial cells (ECs) and a core formed by either type I collagen and αSMA+ cells (presenting a pericyte/smooth muscle cell aspect) or thrombotic components, and c) a similar piecemeal angiogenic mechanism in papillary formation, including sprouting of intimal ECs toward the vessel wall itself or intravascular thrombi, formation of vascular loops that encircle and separate vessel wall or thrombus components, and parietal or thrombotic papillae development. The major differences between both entities were the number, arrangement and substrate of papillae: myriad, densely grouped, parietal and thrombotic papillae in IPEH, and a linear arrangement of predominant parietal papillae in sinusoidal hemangioma, originating septa (segmentation). In conclusion, sinusoidal hemangioma and IPEH are interrelated processes, which share morphologic findings and a piecemeal angiogenic mechanism, combining sprouting and intussusceptive angiogenesis, and leading to papillary formation and vessel segmentation.  相似文献   
69.
The outcome of allogeneic hematopoietic stem cell transplantation (HCT) in patients with myeloid malignancies is better in those without minimal residual disease (MRD) than in those with MRD+,?as assessed by multiparametric flow cytometry (MPFC). WT1 quantitation also has been used to assess the probability of relapse in acute myelogenous leukemia (AML) treated with chemotherapy. We analyzed the clinical value of normalized bone marrow WT1 levels as a measure of the expanded myeloid progenitor compartment in a consecutive series of 193 adult patients with myeloid malignancies who underwent HCT. Bone marrow WT1 levels before the HCT, at the first bone marrow aspirate after infusion, and in the follow-up samples after HCT were determined by means of real-time PCR using the European LeukemiaNet normalized method. We sought to clarify the prognostic relevance in terms of overall survival (OS), progression-free survival (PFS), and cumulative incidence of relapse (CIR). Based on earlier experience in AML, we selected a threshold of 100 copies, defining 2 groups: patients with <100 WT1 copies and those with ≥100 copies. Patients with <100 WT1 copies before HCT (median time, 36 days; range, 4 to 268 days) had a better OS, PFS, and CIR than those with ≥100 copies (40?±?1 versus 29?±?6 days, P = .004; 35?±?9 versus 26?±?6 days, P = .002; and 29?±?7 versus 37?±?6 days, P = .051). In the first bone marrow study after the HCT (median time, 42 days; range 14 to 157 days, respectively), patients with <100 WT1 copies also had better outcomes in terms of OS, PFS, and CIR (40?±?7 versus 31?±?9 days, P = .025; 36?±?7 versus 30?±?8 days, P = .004; and 29?±?6 days versus 54?±?9, P?<?.001, respectively). At this time point, bone marrrow samples with >100 copies also included patients who were negative for MRD as assessed by MPFC (19 of 32). During the HCT follow-up, patients with sustained WT1 levels <100 copies showed a marked benefit in terms of OS, PFS, and CIR even compared with those with only a single measurement >100 copies (mean, 68?±?11 versus 26?±?7 days, P?<?.001; 63?±?11 versus 20?±?8 days, P?<?.001; and 20?±?8 vs. 71?±?8 days, P?<?.001, respectively). Standardized bone marrow WT1 levels using a 100-copy threshold in samples obtained before HCT, at leukocyte recovery, and during follow-up provided relevant prognostic information in patients with myeloid malignacies submitted to HCT.  相似文献   
70.
The Educational Model to Develop Entrustable Professional Activities (MEDAPROC) arises as a response to the implementation of competency-based education. It is a multidisciplinary project based on interpretative epistemology, the constructivist paradigm, the transformations of the national health system, and the context of the current practice of medicine. Its purpose is to encourage the acquisition of essential knowledge, skills, and attitudes by the medical student. It integrates the international trend of the entrustable professional activities and converts them into entrustable professional activities (APROC). MEDAPROC proposes that the development of the APROC be promoted in an inverse manner, from the profile of the graduate to the beginning of the undergraduate studies. Therefore, it is involved in several phases of the learning and teaching process (planning, didactics, assessment, and feedback) through projects to implement didactic strategies and assessment resources, with the support of teacher training, educational research, and technology. Its aim is to improve medical and health sciences education, with the firm purpose of making a positive change in the health care quality from the educational environment.  相似文献   
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