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Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients.  相似文献   
3.
《Brain stimulation》2020,13(4):943-952
BackgroundIntermittent theta-burst stimulation (iTBS), a novel repetitive transcranial magnetic stimulation (rTMS) technique, appears to have antidepressant effects when applied over left dorsolateral prefrontal cortex (DLPFC). However, its underlying neurobiological mechanisms are unclear. Proton magnetic resonance spectroscopy (1H-MRS) provides in vivo measurements of cerebral metabolites altered in major depressive disorder (MDD) like N-acetyl-aspartate (NAA) and choline-containing compounds (Cho). We used MRS to analyse effects of iTBS on the associations between the shifts in the NAA and Cho levels during therapy and MDD improvement.MethodsIn-patients with unipolar MDD (N = 57), in addition to treatment as usual, were randomized to receive 20 iTBS or sham stimulations applied over left DLPFC over four weeks. Single-voxel 1H-MRS of the anterior cingulate cortex (ACC) was performed at baseline and follow-up. Increments of concentrations, as well as MDD improvement, were defined as endpoints. We tested a moderated mediation model of effects using the PROCESS macro (an observed variable ordinary least squares and logistic regression path analysis modeling tool) for SPSS.ResultsImprovement of depressive symptoms was significantly associated with decrease of Cho/NAA ratio, mediated by NAA. iTBS had a significant moderating effect enhancing the relationship between NAA change and depression improvement.ConclusionsOur findings suggest a potential neurochemical pathway and mechanisms of antidepressant action of iTBS, which may moderate the improvement of metabolic markers of neuronal viability. iTBS might increase neuroplasticity, thus facilitating normalization of neuronal circuit function.  相似文献   
4.
《Brain stimulation》2020,13(5):1211-1217
BackgroundAccelerated intermittent Theta Burst Stimulation (aiTBS) has been shown to be an effective antidepressant treatment. Although neurobiological changes shortly after this intervention have been reported, whether aiTBS results in structural brain changes must still be determined. Furthermore, it possible that rapid volumetric changes are driven by factors other than neurotrophic processes.ObjectivesWe examined whether possible grey matter volumetric (GMV) increases after aiTBS treatment could be driven by increased brain perfusion, measured by Arterial Spin Labeling (ASL).Methods46 treatment-resistant depressed patients were randomized to receive 20 sessions of active or sham iTBS applied to the left dorsolateral prefrontal cortex. All sessions were delivered over 4 days at 5 sessions per day (trial registration: http://clinicaltrials.gov/show/NCT01832805). Patients were scanned the day before starting stimulation and three days after aiTBS.ResultsThere was a significant cluster of increased left hippocampal GMV in the dentate gyrus related to HRSD changes after active aiTBS, but not after sham stimulation. These GMV increases became more pronounced when accounting for changes in cerebral perfusion.ConclusionsActive, but not sham, aiTBS, resulted in acute volumetric changes in parts of the left dentate gyrus, suggesting a connection with adult neurogenesis. Furthermore, taking cerebral perfusion measurements into account impacts on detection of the GMV changes. Whether these hippocampal volumetric changes produced by active aiTBS are necessary for long-term clinical improvement remains to be determined.  相似文献   
5.

BACKGROUND CONTEXT

Lumbar spinal stenosis (LSS) can impair blood flow to the spinal nerves giving rise to neurogenic claudication and limited walking ability. Reducing lumbar lordosis can increases the volume of the spinal canal and reduce neuroischemia. We developed a prototype LSS belt aimed at reducing lumbar lordosis while walking.

PURPOSE

The aim of this study was to assess the short-term effectiveness of a prototype LSS belt compared to a lumbar support in improving walking ability in patients with degenerative LSS.

STUDY DESIGN

This was a two-arm, double-blinded (participant and assessor) randomized controlled trial.

PATIENT SAMPLE

We recruited 104 participants aged 50 years or older with neurogenic claudication, imaging confirmed degenerative LSS, and limited walking ability.

OUTCOME MEASURES

The primary measure was walking distance measured by the self-paced walking test (SPWT) and the primary outcome was the difference in proportions among participants in both groups who achieved at least a 30% improvement in walking distance from baseline using relative risk with 95% confidence intervals.

METHODS

Within 1 week of a baseline SPWT, participants randomized to the prototype LSS belt group (n=52) and those randomized to the lumbar support group (n=52) performed a SPWT that was conducted by a blinded assessor. The Arthritis Society funded this study ($365,000 CAN) with salary support for principal investigator funded by the Canadian Chiropractic Research Foundation ($500,000 CAN for 5 years).

RESULTS

Both groups showed significant improvement in walking distance, but there was no significant difference between groups. The mean group difference in walking distance was ?74 m (95% CI: ?282.8 to 134.8, p=.49). In total, 62% of participants wearing the prototype LSS belt and 82% of participants wearing the lumbar support achieved at least 30% improvement in walking distance (relative risk, 0.7; 95% CI: 0.5–1.3, p=.43).

CONCLUSIONS

A prototype LSS belt demonstrated significant improvement in walking ability in degenerative LSS but was no better than a lumbar support.  相似文献   
6.
In the light of relationships reported between hypoxemia (tissue hypoxia) and cancer, Abrams et al. concluded in 2008 that sleep apnea-hypopnea syndrome (SAHS) and its main consequence, intermittent hypoxia, could be related with increased susceptibility to cancer or poorer prognosis of a pre-existing tumor. This pathophysiological association was confirmed in animal studies. Two large independent historical cohort studies subsequently found that the degree of nocturnal hypoxia in patients with SAHS was associated with higher cancer incidence and mortality. This finding has been confirmed in almost all subsequent studies, although the retrospective nature of some requires that they be considered as hypothesis-generating only. The relationship between sleep apnea and cancer, and the pathophysiological mechanisms governing it, could be clarified in the near future in a currently on-going study in a large group of melanoma patients.  相似文献   
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8.
《Journal of vascular surgery》2020,71(4):1340-1345
ObjectiveThe purpose of this exploratory study was to determine whether a single session of vibration therapy (VT) would improve muscular and functional performance in individuals with symptomatic peripheral artery disease (PAD).MethodsIn a randomized, balanced cross-over design fourteen PAD participants with intermittent claudication (mean ± standard deviation; age, 73.9 ± 4.6 years; height, 172.6 ± 68.4 cm; body mass, 85.2 ± 15.7 kg) performed VT and control that involved repeated chair rises, timed up-and-go test, and 6-minute walk test. Each intervention was separated by at least 2 days. Wearable VT devices were positioned on the right and left lower limbs that were turned on during functional testing but were turned off for the control intervention.ResultsVT significantly improved (P < .05) repeated chair rises and timed up-and-go test compared with control with a small effect size of 0.46 and 0.45, respectively. Similarly, a significant (P < .01) and meaningful change in 6-minute walk test was noted in VT compared with control.ConclusionsThis exploratory study suggest that VT may enhance functional strength, mobility, and walking performance by extending the onset of claudication and increasing walking distance in PAD with intermittent claudication. However, further study is required to confirm and extend these preliminary findings and determine the potential mechanisms of action in VT.  相似文献   
9.
目的 探讨间歇性腹膜透析对长期维持腹膜透析患者尿毒症脑病的治疗效果。方法 选择2013年1月-2018年12月本院肾内科长期维持腹膜透析出现尿毒症脑病患者46 例,并随机分为持续性不卧床腹膜透析(Continuous ambulatory peritoneal dialysis,CAPD)组及间歇性腹膜透析(Intermittent peritoneal dialysis,IPD)组,在治疗前及治疗7 d后分别采血进行血肌酐(Scr)、尿素氮(BUN)、甲状旁腺激素(iPTH)、白细胞介素6(IL-6)、β2微球蛋白(β2-MG)、超敏C反应蛋白(CRP)水平的检测,采用阳性与阴性症状量表评分表(PAN - SS)评价患者的疗效。结果 CAPD组治疗后血BUN、Scr、iPTH、IL-6、β2-MG、CRP水平与治疗前比较无明显变化(P>0.05); IPD组治疗后血BUN、Scr水平与治疗前比较无明显变化(P>0.05),而iPTH、IL-6、β2-MG、CRP水平较治疗前明显下降(P<0.05); 治疗后IPD组iPTH、IL-6、β2-MG、CRP水平与CAPD组比较有明显差异(P<0.05); PAN-SS显示,IPD组与CAPD组阳性症状、阴性症状、一般精神症状等方面均有明显差异(P<0.05); CAPD组无效8例,好转12例,显著进步4例,基本痊愈2例; IPD组无效2例,好转14例,显著进步5例,基本痊愈5例。结论 规律腹膜透析患者出现尿毒症脑病时应用间歇性腹膜透析治疗效果优于持续不卧床腹膜透析  相似文献   
10.
BackgroundOne of the research interests with regard to accelerometry is the evaluation of physical activity bout under free-living conditions.Research questionThis study aimed to examine the effect of treatment interruption on the estimation of heart rate (HR) response to moderate-to-vigorous intensity physical activity (MVPA) bout.MethodsTwenty-five young women performed at least 30 min of MVPA during 24 h while wearing a uniaxial accelerometer on their waist and a portable HR monitor on their chest simultaneously. Based on the time series data, MVPA bout was defined as physical activity that was maintained at no less than 3 metabolic equivalents (METs) for >10 min without or with interruption, i.e., a 1-, 2-, or 3-min interruption.ResultsThe frequency and duration of MVPA bout significantly increased with interruption (p < 0.01). The HR and estimated MET value for an MVPA bout with interruption were significantly lower than those without interruption (p < 0.01), and the difference gradually increased depending on the duration of the interruptions (p < 0.01).SignificanceThese findings indicate that treatment interruptions could influence the estimation of cardiorespiratory response to MVPA bout under free-living conditions, and interruptions could result in an overestimation of the actual intensity of an MVPA bout.  相似文献   
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