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Peiying Liu Hao Huang Nancy Rollins Lina F. Chalak Tina Jeon Cathy Halovanic Hanzhang Lu 《NMR in biomedicine》2014,27(3):332-340
The cerebral metabolic rate of oxygen (CMRO2) is the rate of oxygen consumption by the brain, and is thought to be a direct index of energy homeostasis and brain health. However, in vivo measurement of CMRO2 is challenging, in particular for the neonatal population, in whom conventional radiotracer methods are not applicable because of safety concerns. In this study, we propose a method to quantify global CMRO2 in neonates based on arteriovenous differences in oxygen content, and employ separate measurements of oxygenation and cerebral blood flow (CBF) parameters. Specifically, arterial and venous oxygenation levels were determined with pulse oximetry and the novel T2 relaxation under spin tagging (TRUST) MRI, respectively. Global CBF was measured with phase contrast (PC) flow velocity MRI. The proposed method was implemented on a standard 3‐T MRI scanner without the need for any exogenous tracers, and the total scan duration was less than 5 min. We demonstrated the feasibility of this method in 12 healthy neonates within an age range of 35–42 gestational weeks. CMRO2 values were successfully obtained from 10 neonates. It was found that the average CMRO2 in this age range was 38.3 ± 17.7 µmol/100 g/min and was positively correlated with age (p = 0.007; slope, 5.2 µmol/100 g/min per week), although the highest CMRO2 value in this age range was still less than half of the adult level. Test–retest studies showed a coefficient of variation of 5.8 ± 2.2% between repeated CMRO2 measurements. In addition, given the highly variable blood flow velocity within this age range, it is recommended that the TRUST labeling thickness and position should be determined on a subject‐by‐subject basis, and an automatic algorithm was developed for this purpose. Although this method provides a global CMRO2 measure only, the clinical significance of an energy consumption marker and the convenience of this technique may make it a useful tool in the functional assessment of the neonatal population. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Adiponectin exerts both vasodilatory and insulin-sensitizing actions and its levels are decreased in insulin-resistant humans and animals. The mechanisms underlying adiponectin?s insulin-sensitizing effect have been extensively investigated but remain largely unclear. Muscle microvasculature critically regulates muscle insulin action by modulating insulin delivery to the microvessels nurturing the muscle cells and the trans-endothelial insulin transport. We have recently reported that adiponectin exerts its insulin-sensitizing effect via recruiting muscle microvasculature, expanding the endothelial surface area, and increasing insulin delivery to and thus action in muscle. The current review focuses on the microvascular connection between the adiponectin and insulin cross talk. 相似文献
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Yuanlong Shen Lina Yu Zhen Hua Ningxin Jia Yanan Zhou Xiaosheng Dong Meng Ding 《Medicine》2021,100(3)
Introduction:Exercise has been believed to have positive effects on blood glucose control in patients with type 2 diabetes mellitus. However, few medical evidences have been found to ascertain which type of exercise has the best effect on blood glucose control in diabetes and which type of exercise is more acceptable. The purpose of this study is to compare the effects and acceptability of different exercise modes on glycemic control in type 2 diabetes patients by using systematic review and network meta-analysis.Methods and analysis:Relevant randomized controlled trial studies will be searched from PubMed, EMbase, CochraneCENTRAL, CNKI, VIP, and Chinese medical paper libraries. Primary outcome indicators: glycosylated hemoglobin and dropout rate of the research (number of dropouts/numbers of initially enrolled subjects). Secondary outcome measures: fasting blood glucose, body weight, total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol, triglycerides (TG), diastolic pressure, systolic pressure (SBP). Two reviewers are arranged to screen Title, Abstract, and then review full text to further extract data. Standard meta-analysis and network meta-analysis of the data are performed afterward. Methodological quality assessment is planned to be conducted using Cochrane risk of bias tool. The outcome will be analyzed statistically according to Bayesian analysis methods. After that, subgroup analysis is conducted on the duration of intervention, whether there is supervision of intervention, frequency of intervention per week, age, gender, and medication use.Trial registration number:PROSPERO CRD42020175181Discussion:The systematic review and network meta-analysis include evidence of the impact of different exercise modes on blood glucose control in type 2 diabetes mellitus. There are 2 innovative points in this study. One is to conduct a classified study on exercise in as much detail as possible, and the other is to study the acceptability of different exercise modes. The network meta-analysis will reduce the uncertainty of intervention and enable clinicians, sports practitioners, and patients to choose more effective and suitable exercise methods.Ethics and dissemination:The findings of the study will be disseminated through publications in peer-reviewed journals and scientific conferences and symposia. Further, no ethical approval is required in this study. 相似文献
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Lina Rosique López Jerónimo Lajara Blesa Mariano Rosique Arias 《Acta otorrinolaringologica espanola》2013,64(4):279-282
Introduction and objectivesEpiphora caused by nasolacrimal drainage system obstruction is the main indication for dacryocystorhinostomy (DCR). So are chronic conjunctivitis and dacryocystitis from the same origin. Nasal endoscopy and the introduction of laser assisted DCR have facilitated the performance of the technique. However, it requires complex and expensive equipment, so there are still supporters of the traditional external procedure.The aim of this work was to study the effectiveness and usefulness of local postoperative care in laser DCR final result.Material and methodsWe studied a group of 96 patients diagnosed with epiphora secondary to stenosis-occlusion of the nasolacrimal duct. Of these, 32 patients underwent surgery in both eyes, making a total of 128 cases. The surgery was performed in a private setting between January 1999 and December 2008. The 128 cases were divided into 2 groups: 59 cases in which between 4 and 6 postoperative cures were given in the 2 months following the surgery, and another group of 69 cases in which a single cure was given approximately 7 days after surgery. The final assessment of the outcome of the intervention was done in all cases between 24-30 months after surgery.ResultsIn 27 cases out of 128 (79% success), there was a restenosis of tear drainage. No statistically significant differences were found between the 2 groups.ConclusionsIn the sample of patients that were intervened using laser assisted DCR, implementation of postoperative cure was irrelevant in the success of the intervention. 相似文献