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1.
2.

Objectives

The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.

Design

Pilot randomised-controlled trial.

Methods

Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.

Results

All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.

Conclusions

This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials.  相似文献   
3.
《Brain stimulation》2020,13(6):1668-1677
BackgroundEndovascular delivery of current using ‘stentrodes’ – electrode bearing stents – constitutes a potential alternative to conventional deep brain stimulation (DBS). The precise neuroanatomical relationships between DBS targets and the vascular system, however, are poorly characterized to date.ObjectiveTo establish the relationships between cerebrovascular system and DBS targets and investigate the feasibility of endovascular stimulation as an alternative to DBS.MethodsNeuroanatomical targets as employed during deep brain stimulation (anterior limb of the internal capsule, dentatorubrothalamic tract, fornix, globus pallidus pars interna, medial forebrain bundle, nucleus accumbens, pedunculopontine nucleus, subcallosal cingulate cortex, subthalamic nucleus, and ventral intermediate nucleus) were superimposed onto probabilistic vascular atlases obtained from 42 healthy individuals. Euclidian distances between targets and associated vessels were measured. To determine the electrical currents necessary to encapsulate the predefined neurosurgical targets and identify potentially side-effect inducing substrates, a preliminary volume of tissue activated (VTA) analysis was performed.ResultsSix out of ten DBS targets were deemed suitable for endovascular stimulation: medial forebrain bundle (vascular site: P1 segment of posterior cerebral artery), nucleus accumbens (vascular site: A1 segment of anterior cerebral artery), dentatorubrothalamic tract (vascular site: s2 segment of superior cerebellar artery), fornix (vascular site: internal cerebral vein), pedunculopontine nucleus (vascular site: lateral mesencephalic vein), and subcallosal cingulate cortex (vascular site: A2 segment of anterior cerebral artery). While VTAs effectively encapsulated mfb and NA at current thresholds of 3.5 V and 4.5 V respectively, incremental amplitude increases were required to effectively cover fornix, PPN and SCC target (mean voltage: 8.2 ± 4.8 V, range: 3.0–17.0 V). The side-effect profile associated with endovascular stimulation seems to be comparable to conventional lead implantation. Tailoring of targets towards vascular sites, however, may allow to reduce adverse effects, while maintaining the efficacy of neural entrainment within the target tissue.ConclusionsWhile several challenges remain at present, endovascular stimulation of select DBS targets seems feasible offering novel and exciting opportunities in the neuromodulation armamentarium.  相似文献   
4.
目的:观察针药结合治疗假性延髓麻痹的疗效。方法:采用完全随机抽样法分为针刺组50例,对照组48例。针刺组在西医治疗的同时,应用针刺进行综合治疗;对照组单纯接受西医药物治疗。结果:针刺组有效率为92.0%,对照组为62.5%。两组疗效差异具有非常显著性意义(P〈0.01)。结论:针药结合治疗假性延髓麻痹效果明显优于单纯西药治疗。  相似文献   
5.
目的 :了解冠心病患者外周循环单核细胞组织因子 (TF)表达与冠心病病情的关系 ;观察溶栓治疗对急性心肌梗死患者单核细胞TF表达的影响。方法 :测定了 2 2例稳定型心绞痛 (SA)患者 ,2 1例不稳定型心绞痛(UA)患者 ,1 5例急性心肌梗死 (AMI)患者用尿激酶溶栓前及溶栓后 ,1 8例健康人外周循环单核细胞组织因子阳性率。单核细胞组织因子阳性率测定用免疫荧光染色及流式细胞术。结果 :SAP组 ,UAP组和AMI组单核细胞TF阳性率高于对照组 ,UAP组和AMI组单核细胞TF阳性率高于SAP组 ,单核细胞TF阳性率与冠心病病情显著相关。急性心肌梗死患者溶栓后 2h单核细胞TF阳性率升高。结论 :外周血单核细胞TF的表达与冠心病病情严重程度密切相关 ;急性心肌梗死患者溶栓治疗后单核细胞TF的表达进一步增强 ,这可能是溶栓后凝血酶活化的原因之一。  相似文献   
6.
Immunohistochemical and immunoelectron microscopical studies were carried out on 28 aged dogs' brains. Amyloid deposits were seen in the arteries and capillaries in the leptomeninges and in superficial areas of the cortices in 19 (67.9%) of the 28 dogs (10-22 years of age). Immunohistochemically, these amyloid deposits were reactive for anti-beta/A4 antibody. Additionally, a variable number of parenchymal deposits with diffuse beta/A4-immunoreactivity (diffuse plaques) was also noted throughout the cerebral cortex in 24/28 dogs (85.7%). However, these plaque lesions were undetectable in Congo red staining. Electron microscopically, amyloid fibrils, measuring 10 nm in width, were located mainly in the tunica media of the arteries, and in less involved vessels they tended to be present among collagen fibres in the adventitia and smooth muscle cells in the outer layer of the media. The plaque lesions appeared to contain sparse aggregations of amyloid fibrils. In immunoelectron microscopical examinations, all amyloid fibrils in both blood vessels and plaques were selectively labelled by gold particles. These findings indicate that aged dogs can provide a useful experimental model for research into the beta/A4-type of cerebral amyloidosis commonly seen in Alzheimer's disease.  相似文献   
7.
陈晨  汪凯 《中国卒中杂志》2007,15(11):1239-1243
尼麦角林是一种麦角生物碱衍生物,广泛应用于脑血管病患者认知障碍的治疗。多项临
床前研究显示,尼麦角林对于认知障碍的改善可能与以下因素有关:尼麦角林除能够改善脑循环,
促进神经递质释放外,还具有营养神经及抗氧化等作用。目前的研究认为,尼麦角林能够改善患者
卒中后抑郁相关的情绪障碍以及有效改善血管性痴呆,提高患者的日常生活能力。同时,尼麦角林具
有良好的安全性,目前暂无尼麦角林治疗导致纤维化或麦角中毒的研究报道。本文就尼麦角林在神
经系统的作用机制、临床疗效及安全性进行综述,以期为临床应用提供参考。  相似文献   
8.
目的对比研究动脉血质子自旋标记(ASL)与动态磁敏感对比(DSC)MRI在急性脑缺血诊断中的应用价值。方法27例发病3d内的急性脑卒中患者,均采用3.0TMR行脉冲式ASL和DSCMR检查。观察2种技术的灌注表现,包括灌注不足、正常灌注、延迟灌注、过度灌注等,采用Mann—Whitney检验做定性分析。在扩散加权成像显示的病变部位及对侧正常半球的镜像区域分别确定3个感兴趣区(ROI),测量信号强度并计算信号强度比(病侧/对照侧),并将结果做配对t检验。结果定性分析显示27例患者中,2l例2种技术检查结果一致(灌注不足14例,正常灌注5例,过度灌注2例)。6例2种技术不一致,其中4例ASL显示灌注不足而DSC显示延迟灌注,2例ASL显示正常灌注而DSC显示延迟灌注,两者间差异无统计学意义(P〉0.05)。定量分析示,2种技术的病侧与对照侧信号强度比值ASL为0.7l±0.46,DSC为0.73±0.42,两者间差异无统计学意义(P〉0.05)。结论无创性ASL技术在检测灌注异常时与DSCMRI有相似的敏感性;ASL可与常规MR检查相结合,为临床诊断急性缺血性卒中提供有价值的信息。  相似文献   
9.
目的 回顾性分析64例急性脑梗死患者的死亡时间,探讨脑梗死患者死亡时间的昼夜节律变化的特点和规律,方法 分析64例死亡病例的临床资料,重点分析死亡时间,利用圆形分布的统计方法,计算出死亡高峰时刻和1天24小时内95%的死亡时间集中时段。结果 急性脑梗死患者的死亡高峰时刻为05:59:31,1天24小时内95%的死亡时间发生在01:04:23-10:54:39.结论 急性脑梗死患者的死亡时间有一定的昼夜节律分布的特点,清晨通常为死亡的高峰时段,与机体血栓性病理状态恶化或血压的昼夜波动有关,工作中应注意加强夜间和凌晨患者的管理和监测,必要时改变投药时间,最大限度地减少死亡率。  相似文献   
10.
本文在兔MCAO局灶脑缺血模型基础上,利用外源性一氧化氮(NO)前体物质L-精氨酸和NOS抑制剂L-NNA研究NO对脑缺血后脑水肿和脑梗塞的影响。NZW兔42只随机分为7组,每组6只,计对照组、假手术组、MCAO组、MCAO+NS组、MCAO+L-Arg组、MCAO+D-Arg组及MCAO+L-Arg+L-NNA组。结果提示:与单纯MCAO组比较,L-Arg组的脑组织H_2O、Na~+、Ca~(2+)含量明显下降(P<0.01),脑梗塞灶亦明显缩小(P<0.01)。从而显示L-Arg系通过产生NO促使血管舒张而减轻脑水肿和缩小梗塞灶,为临床改进脑缺血的治疗提供依据。  相似文献   
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