asymmetry

不对称
  • 文章类型: Journal Article
    临床步行测试可能无法预测健康老年人的虚弱发展。随着可穿戴技术的进步,在临床步行试验中,利用负荷不对称参数可能预测虚弱的发展.这项前瞻性队列研究旨在检验以下假设:肢体负荷不对称性增加可预测社区生活老年人的虚弱风险。招募了63名年龄≥65岁的社区生活成年人,47名受试者在基线后完成了为期10个月的随访.净负荷和区域负荷不对称指数(前脚,中足,和后足)足底力是在10m步行测试中以最大速度使用力感测鞋垫收集的。如果参与者在随访期间使用Kihon清单从基线至少一个虚弱分级组进展,则定义虚弱的发展。14名受试者在随访期间出现虚弱。虚弱风险的增加与净冲量负荷不对称性每增加1%相关(赔率1.153,95CI1.001至1.329)。净脉冲不对称性与足中力峰值力的不对称性显着相关。这些结果表明在临床步行测试中测量步态足底力的可行性,并强调了使用负荷不对称性作为增强社区居住老年人虚弱风险评估的工具的潜力。
    Clinical walk tests may not predict the development of frailty in healthy older adults. With advancements in wearable technology, it may be possible to predict the development of frailty using loading asymmetry parameters during clinical walk tests. This prospective cohort study aimed to test the hypothesis that increased limb loading asymmetry predicts frailty risk in community-living older adults. Sixty-three independently ambulant community-living adults aged ≥ 65 years were recruited, and forty-seven subjects completed the ten-month follow-up after baseline. Loading asymmetry index of net and regional (forefoot, midfoot, and rearfoot) plantar forces were collected using force sensing insoles during a 10 m walk test with their maximum speed. Development of frailty was defined if the participant progressed from baseline at least one grading group of frailty at the follow-up period using the Kihon Checklist. Fourteen subjects developed frailty during the follow-up period. Increased risk of frailty was associated with each 1% increase in loading asymmetry of net impulse (Odds ratio 1.153, 95%CI 1.001 to 1.329). Net impulse asymmetry significantly correlated with asymmetry of peak force in midfoot force. These results indicate the feasibility of measuring plantar forces of gait during clinical walking tests and underscore the potential of using load asymmetry as a tool to augment frailty risk assessment in community-dwelling older adults.
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  • 文章类型: Journal Article
    左右两侧之间的不对称似乎是Bilateria神经系统组织的一般原则,为从秀丽隐杆线虫到人类的物种中记录的过多的向左和向右的行为偏见提供了基础。已经提出了几种理论来解释在个体和群体水平上大脑不对称组织的进化中的存在和维持。然而,在对大脑不对称的进化进行理论化时,缺少的是一个总体的一般假设,它可能包含当前模型的所有不同方面。这里,我们试图提供一个基于能量和自由能最小化原理的总体框架,这在神经科学的其他领域被证明是非常有价值的。我们发现,在个体水平上,反对称单线态配置实现了系统的最低能量状态,而在团体层面,方向不对称性的自发出现是由于系统自由能的最小化而产生的,这保证了它的稳定和平衡。因此,我们认为,在生物学中已经捕捉到的大脑不对称的各种现象学方面-例如,保留神经组织,单一电机响应的控制,在人口层面,数学博弈论描述的进化稳定策略-可以被认为是更一般的能量最小化原理的体现,其中,大脑的不对称。
    The asymmetry between the left and right sides seems to be a general principle of organization of the nervous systems in Bilateria, providing the foundations for a plethora of leftward and rightward biases in behaviour as documented in species ranging from Caenorhabditis elegans nematodes to humans. Several theories have been put forward to account for the existence and maintenance in the evolution of the asymmetric organization of the brain at both individual and population levels. However, what is missing in theorizing about the evolution of brain asymmetry is an overarching general hypothesis that may subsume all different aspects of current models. Here, we tried to provide an overarching general framework based on the energy and free-energy minimization principle, which proved so valuable in other areas of neuroscience. We found that at the individual level the antisymmetric singlet configuration realizes the lowest energy state of the system, whereas at the group level, the spontaneous emergence of directional asymmetry arises as a consequence of the minimization of the free energy of the system, which guarantees its stability and equilibrium. We thus argue that the various phenomenological aspects of brain asymmetry that have been captured in biology-e.g. sparing of neural tissue, control of unitary motor responses and, at the population level, evolutionarily stable strategies described by mathematical games theory-may be thought of as the manifestation of a more general principle of energy minimization generating, among others, asymmetry of the brains.
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  • 文章类型: Journal Article
    目的:本研究的目的是客观评估儿童非综合征性单侧唇腭裂(UCLP)初次治疗后残留的面部不对称程度,并将其与面部外观的主观评分相关联。
    方法:采用立体测光法记录89例UCLP患儿的面部,以比较原发性裂口闭合后5年内的裂口侧和非裂口侧。计算均方根值以测量面部的left裂和非left裂的形状之间的差异,并与没有left裂的对照组进行比较。Asher-McDade美学指数(AMAI)用于通过12名外行人对鼻唇面积进行主观评分。
    结果:唇裂(CL)患儿的RMS值与对照组相比没有显着差异。当评估仅限于鼻唇沟区时,发生了显着差异,然而,仅在唇裂(CLA)和唇裂(CLAP)患者中(p<0.001)。相比之下,主观评分显示,所有三个裂隙严重程度组的值均显着较高(CL,CLA,CLAP)与对照组相比(p<0.001)。RMS(均方根)值与AMAI评分之间存在非线性相关性。
    结论:在UCLP初次闭合后,即使儿童面部对称性的非显著离散客观偏差也在主观评分中被警惕地记录,并在面部外观的判断中实施。
    结论:3D立体测光术是一种监测裂患者不对称性的有效工具。
    OBJECTIVE: The aim of the present study was to objectively assess the degree of residual facial asymmetry after primary treatment of non-syndromic unilateral cleft lip and palate (UCLP) in children and to correlate it with subjective ratings of facial appearance.
    METHODS: Stereophotometry was used to record the faces of 89 children with UCLP for comparison of cleft and non-cleft sides up to 5 years after primary cleft closure. Root mean square values were calculated to measure the difference between the shape of cleft and non-cleft sides of the face and were compared to controls without a cleft lip. The Asher-McDade Aesthetic Index (AMAI) was used for subjective rating of the nasolabial area through 12 laypersons.
    RESULTS: Children with a cleft lip (CL) showed no significant difference in RMS values compared to controls. Significant differences occurred when the evaluation was limited to the nasolabial area, however only in patients with cleft lip alveolus (CLA) and cleft lip palate (CLAP)(p < 0.001). In contrast, subjective ratings showed significantly higher values for all three cleft severity groups (CL, CLA, CLAP) compared to controls (p < 0.001). There was a non-linear correlation between the RMS (root mean square) values and the AMAI score.
    CONCLUSIONS: Even non-significant discrete objective deviations from facial symmetry in children after primary closure of UCLP are vigilantly registered in subjective ratings and implemented in the judgement of facial appearance.
    CONCLUSIONS: 3D stereophotometry is a usefull tool in monitoring asymmetry in patients with a cleft.
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  • 文章类型: Journal Article
    只有少数研究评估了儿童和青春期两个半球之间的结构差异。然而,现有的研究结果缺乏一致性或仅限于特定的大脑区域,一个特定的大脑特征,或相对狭窄的年龄范围。这里,我们在迄今为止最大的儿科样本之一(n=4265)中调查了大脑不对称与年龄和性别之间的关联,1-18岁,在参加ENIGMA(通过Meta分析增强神经影像学遗传学)联盟的69个站点进行扫描。我们的研究表明,儿童时期已经存在显著的大脑不对称,但是它们的大小和方向取决于所检查的大脑区域和使用的形态测量(皮质体积或厚度,区域表面积,或皮质下体积)。关于年龄的影响,随着时间的推移,一些不对称性变得越来越弱,而另一些则变得越来越强;有时他们甚至颠倒了方向。关于性别差异,女性表现出显著不对称性的区域总数大于男性,而在男性中,表明显著不对称的测量总数更大(因为我们在每个皮质区域获得了一个以上的测量值)。男性的显着不对称程度也更大。然而,年龄效应和性别差异的效应大小都很小。一起来看,这些发现表明,大脑不对称是大脑固有的组织模式,表现在生命早期。总的来说,大脑不对称在整个童年和青春期似乎相对稳定,对男性和女性有不同的影响。
    Only a small number of studies have assessed structural differences between the two hemispheres during childhood and adolescence. However, the existing findings lack consistency or are restricted to a particular brain region, a specific brain feature, or a relatively narrow age range. Here, we investigated associations between brain asymmetry and age as well as sex in one of the largest pediatric samples to date (n = 4265), aged 1-18 years, scanned at 69 sites participating in the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) consortium. Our study revealed that significant brain asymmetries already exist in childhood, but their magnitude and direction depend on the brain region examined and the morphometric measurement used (cortical volume or thickness, regional surface area, or subcortical volume). With respect to effects of age, some asymmetries became weaker over time while others became stronger; sometimes they even reversed direction. With respect to sex differences, the total number of regions exhibiting significant asymmetries was larger in females than in males, while the total number of measurements indicating significant asymmetries was larger in males (as we obtained more than one measurement per cortical region). The magnitude of the significant asymmetries was also greater in males. However, effect sizes for both age effects and sex differences were small. Taken together, these findings suggest that cerebral asymmetries are an inherent organizational pattern of the brain that manifests early in life. Overall, brain asymmetry appears to be relatively stable throughout childhood and adolescence, with some differential effects in males and females.
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  • 文章类型: Journal Article
    结构和功能的不对称在每一种生命形式中都可以追溯到,和一些侧缘是同源的。从功能上讲,大脑两半之间的分工是神经系统的基本特征,甚至在脊椎动物出现之前就出现了。这种专业化在人类中最著名的表达是手支配,也被称为惯用手。即使手/肢/爪优势与神经系统的存在更常见,它也以其自身的形式在非生物体中观察到,比如植物。迄今为止,关于这种优势在植物中可能的功能意义知之甚少,许多问题仍然悬而未决(其中,它是否反映了广义的行为不对称)。这里,我们提出了一种比较方法来研究惯用手法,包括植物,通过利用已经用于研究人类和各种动物物种的侧向性的实验模型和范例。通过这种方法,我们的目标是丰富我们对自然王国中惯用手的概念的了解。
    Structural and functional asymmetries are traceable in every form of life, and some lateralities are homologous. Functionally speaking, the division of labour between the two halves of the brain is a basic characteristic of the nervous system that arose even before the appearance of vertebrates. The most well-known expression of this specialisation in humans is hand dominance, also known as handedness. Even if hand/limb/paw dominance is far more commonly associated with the presence of a nervous system, it is also observed in its own form in aneural organisms, such as plants. To date, little is known regarding the possible functional significance of this dominance in plants, and many questions remain open (among them, whether it reflects a generalised behavioural asymmetry). Here, we propose a comparative approach to the study of handedness, including plants, by taking advantage of the experimental models and paradigms already used to study laterality in humans and various animal species. By taking this approach, we aim to enrich our knowledge of the concept of handedness across natural kingdoms.
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  • 文章类型: Journal Article
    步行的自适应控制通常在分体式跑步机上进行研究,在那里,人们通过调整脚的位置和时间逐渐减少他们的步长不对称(SLA)。尽管有人提出这种适应可能部分地由减少不稳定性的愿望驱动,不对称的变化是否会影响人们在应对不稳定扰动时保持平衡的能力,这是未知的。这里,我们使用间歇性扰动来确定SLA的变化是否会影响通过矢状面和额面中的全身角动量(WBAM)测量的反应平衡控制。16名神经典型的老年人(70.0±5.3岁;6名男性)以2:1的皮带速度比在跑步机上行走,并实时视觉反馈其已达到的步长和目标步长。我们使用混合效应模型来确定在施加扰动期间SLA或足部放置与WBAM之间是否存在关联。在扰动过程中,使用更多积极的SLA行走与前向WBAM的少量减少有关(快带和慢带的p<0.001),但横向WBAM增加(快带的p=0.045;慢带的p=0.003)。当参与者以更积极的SLA行走时,他们缩短了脚在慢腰带上的位置,在慢带扰动期间,这种缩短与正向WBAM的适度减少(p<0.001)和横向WBAM的小幅增加(p=0.008)有关。我们的发现表明,在分裂皮带跑步机行走过程中发生的时空变化可以通过降低人们对失平衡的敏感性来改善矢状面稳定性。但这可能是以牺牲正面稳定为代价的。
    The adaptive control of walking is often studied on a split-belt treadmill, where people gradually reduce their step length asymmetries (SLAs) by modulating foot placement and timing. Although it is proposed that this adaptation may be driven in part by a desire to reduce instability, it is unknown if changes in asymmetry impact people\'s ability to maintain balance in response to destabilizing perturbations. Here, we used intermittent perturbations to determine if changes in SLA affect reactive balance control as measured by whole-body angular momentum (WBAM) in the sagittal and frontal planes. Sixteen neurotypical older adults (70.0 ± 5.3 years old; 6 males) walked on a treadmill at a 2:1 belt speed ratio with real-time visual feedback of their achieved and target step lengths. We used mixed-effects models to determine if there were associations between SLA or foot placement and WBAM during the applied perturbations. Walking with more positive SLAs was associated with small reductions in forward WBAM (p < 0.001 for fast and slow belts) but increased lateral WBAM (p = 0.045 for fast belt; p = 0.003 for slow belt) during perturbations. When participants walked with more positive SLAs, they shortened their foot placement on the slow belt, and this shortening was associated with moderate reductions in forward WBAM (p < 0.001) and small increases in lateral WBAM (p = 0.008) during slow-belt perturbations. Our findings suggest that spatiotemporal changes that occur during split-belt treadmill walking may improve sagittal-plane stability by reducing people\'s susceptibility to losses of balance, but this may come at the expense of frontal-plane stability.
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  • 文章类型: Journal Article
    在这项探索性研究中,我们比较和对比了两种从功能磁共振成像(fMRI)数据中得出侧向指数(LI)的方法:LI工具箱中的加权自举平均值(工具箱方法),以及一种新颖的方法,该方法使用从左半球和右半球的同源区域中减去激活来给出一系列差异分数(镜像方法)。数据来自31个人,这些人在接受功能性经颅多普勒超声(fTCD)测试时被选中,其中包括高比例的非典型偏侧人群。在两个任务上,单词生成和语义匹配,与工具箱法相比,镜像法通常与FTCD侧向性具有更好的一致性,无论是针对单个感兴趣的区域,和对应于大脑中动脉的大区域。这种方法的LI估计的置信区间(CI)比工具箱方法的置信区间小得多;使用镜像方法,大多数参与者被可靠地侧向向左或向右,而使用工具箱方法,较高的比例被归类为双边(即,LI的CI跨越零)。讨论了fMRI方法之间差异的原因:一个问题是工具箱方法在广泛的阈值范围内平均LI。此外,对来自两个半球的任务相关t统计图的检查表明,语言偏侧化在以失活为特征的区域中是明显的,所以关键信息可能会因为忽略零以下的体素激活而丢失,正如传统的LI估计所做的那样。
    In this exploratory study we compare and contrast two methods for deriving a laterality index (LI) from functional magnetic resonance imaging (fMRI) data: the weighted bootstrapped mean from the LI Toolbox (toolbox method), and a novel method that uses subtraction of activations from homologous regions in left and right hemispheres to give an array of difference scores (mirror method). Data came from 31 individuals who had been selected to include a high proportion of people with atypical laterality when tested with functional transcranial Doppler ultrasound (fTCD). On two tasks, word generation and semantic matching, the mirror method generally gave better agreement with fTCD laterality than the toolbox method, both for individual regions of interest, and for a large region corresponding to the middle cerebral artery. LI estimates from this method had much smaller confidence intervals (CIs) than those from the toolbox method; with the mirror method, most participants were reliably lateralised to left or right, whereas with the toolbox method, a higher proportion were categorised as bilateral (i.e., the CI for the LI spanned zero). Reasons for discrepancies between fMRI methods are discussed: one issue is that the toolbox method averages the LI across a wide range of thresholds. Furthermore, examination of task-related t-statistic maps from the two hemispheres showed that language lateralisation is evident in regions characterised by deactivation, and so key information may be lost by ignoring voxel activations below zero, as is done with conventional estimates of the LI.
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  • 文章类型: Journal Article
    多巴胺能神经元的脑不对称性在帕金森病运动症状中的作用尚不明确。来自丘脑底核的局部现场记录揭示了该疾病的一些神经生理学生物标志物:增加的β活性,增加了低频活动和高频振荡。相位-振幅耦合协调神经元活动的定时,并允许确定大脑不同区域内的通信机制。在这项研究中,我们讨论了使用相位-振幅耦合评估左旋多巴给药前后24例帕金森病患者的两个半球之间的差异。将丘脑低(12-20Hz)和高β(20-30Hz)振荡与低(30-45Hz)振荡进行了比较,中(70-100赫兹)和高频(260-360赫兹)频段。我们发现左右之间存在明显的β相位-振幅耦合不对称性,并且药物治疗具有相反的依赖性作用,这与运动症状的减少有关。特别是,当评估右下丘脑时,在OFF条件(P<0.01)和ON状态(P<0.0001)期间发现高频和高β振荡之间的高耦合,而在分析中考虑左下丘脑时,情况正好相反,在OFF条件下,高频和高β振荡之间的耦合较低(P<0.01),其次是较高的一个在ON状态(P<0.01)。有趣的是,这些不对称性独立于运动开始侧,左或右。这些发现对神经信号具有重要意义,这些神经信号可用于在帕金森氏症中触发自适应深部脑刺激,并可以提供对丘脑下动力学的更详尽的见解。
    The role of brain asymmetries of dopaminergic neurons in motor symptoms of Parkinson\'s disease is still undefined. Local field recordings from the subthalamic nucleus revealed some neurophysiological biomarkers of the disease: increased beta activity, increased low-frequency activity and high-frequency oscillations. Phase-amplitude coupling coordinates the timing of neuronal activity and allows determining the mechanism for communication within distinct regions of the brain. In this study, we discuss the use of phase-amplitude coupling to assess the differences between the two hemispheres in a cohort of 24 patients with Parkinson\'s disease before and after levodopa administration. Subthalamic low- (12-20 Hz) and high-beta (20-30 Hz) oscillations were compared with low- (30-45 Hz), medium- (70-100 Hz) and high-frequency (260-360 Hz) bands. We found a significant beta-phase-amplitude coupling asymmetry between left and right and an opposite-side-dependent effect of the pharmacological treatment, which is associated with the reduction of motor symptoms. In particular, high coupling between high frequencies and high-beta oscillations was found during the OFF condition (P < 0.01) and a low coupling during the ON state (P < 0.0001) when the right subthalamus was assessed; exactly the opposite happened when the left subthalamus was considered in the analysis, showing a lower coupling between high frequencies and high-beta oscillations during the OFF condition (P < 0.01), followed by a higher one during the ON state (P < 0.01). Interestingly, these asymmetries are independent of the motor onset side, either left or right. These findings have important implications for neural signals that may be used to trigger adaptive deep brain stimulation in Parkinson\'s and could provide more exhaustive insights into subthalamic dynamics.
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  • 文章类型: Journal Article
    有不同的理论被引用为运动病的原因。不对称耳石器官功能是晕动病的病因学理论之一。在我们的研究中,目的是揭示在晕船的病理生理学中是否存在起源于囊性反射途径的原因。在我们的研究中,患者组包括15名诊断为晕船的男子水手,对照组包括15名没有晕船的男子水手。比较两组之间的颈诱发肌源性前庭电位(cVEMP)发现。在水手们晕船的左右耳朵里,发现在100、95和90dB正常听力水平(nHL)水平下,p13和n23波的平均潜伏期明显短于对照组(全部p<0.05)。在晕船组,发现100nHL水平的cVEMP耳间波振幅不对称率明显高于对照组(p=0.001)。我们的研究结果表明,在晕船的病理生理学中,可能存在从糖反射途径引起的原因。
    There are different theories cited as the cause of Motion Sickness. Asymmetrical otolithic organ function is one of the etiology theories of motion sickness. In our study, the aim was to reveal whether there is a cause originating from the sacculocolic reflex pathway in the physiopathology of seasickness. The patient group included 15 man sailors with diagnosis of seasickness and the control group included 15 man sailors without seasickness in our study. Cervical evoked myogenic vestibular potential (cVEMP) findings were compared between the groups. In the right and left ears of sailors with seasickness, the mean latencies of the p13 and n23 waves at 100, 95, and 90 dB normal hearing level (nHL) levels were found significantly shorter than in the control group (p < 0.05, for all). In the seasickness group, cVEMP interaural wave amplitude asymmetry ratio at 100 nHL level were found significantly higher than the control group (p = 0.001). The findings of our study indicated that there may be reasons arising rom the sacculocolic reflex pathway in the pathophysiology of seasickness.
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  • 文章类型: Journal Article
    鼻中隔对颅面结构的发育至关重要。鼻中隔偏离是口腔呼吸的解剖学原因之一,进而导致咬合不正。
    为了评估鼻中隔偏曲引起的鼻呼吸阻塞的患者的颌面和头颅特征,以及这些缺陷与各种错牙合之间的关系以及面部不对称程度。
    对选定的患者采用两点评估,一个在耳鼻喉科使用临床检查和CT-PNS和根据Mladina分类分类的严重程度,另一个在牙科部门,使用临床检查,PA脑电图,外侧脑电图,和面部照片。
    咬合不正与各种等级的间隔偏离之间的关联具有统计学意义,P值为0.006。结果显示13例患者具有I类骨骼模式,20名II类患者,和7例III类骨骼模式患者。7级鼻中隔偏曲患者均无I类错合,2级鼻中隔偏曲患者均无III类错合。II类I类错牙合是鼻中隔偏曲患者中最常见的类型。7级鼻中隔偏曲与最大ANS量相关,上述偏曲表明面部不对称。
    II类1类错牙合畸形是最常见的类型,而III类错牙合畸形在较高等级的鼻中隔偏曲中更为常见。上颌和下颌不对称性随鼻中隔偏曲程度的增加而显着恶化,是引起面部不对称性的重要因素之一。
    UNASSIGNED: The nasal septum is crucial in the development of the craniofacial structures. Deviated nasal septum is one of the anatomical causes of mouth breathing which in turn lead to malocclusion.
    UNASSIGNED: To evaluate the dentofacial and cephalometric characteristics in individuals with nasal breathing obstruction brought on by nasal septal deviation, as well as the relationship between these defects and various malocclusions and the degree of facial asymmetry.
    UNASSIGNED: A two-point evaluation was adopted for the selected patients, one at the ENT department using clinical examination and CT-PNS and the severity classified according to the Mladina classification and another at the dental department, using clinical examinations, PA cephalograms, lateral cephalograms, and facial photographs.
    UNASSIGNED: The association between malocclusion and various grades of septal deviation was statistically significant with a P value of 0.006. Results showed that 13 patients are with Class I skeletal pattern, 20 patients with Class II, and 7 patients with Class III skeletal pattern. None of the grade 7 nasal septal deviation patients had class I malocclusion and none of the grade 2 nasal septal deviation patients had class III malocclusion. Class II division I malocclusion was the most common type noted in patients with nasal septal deviation. Grade 7 nasal septal deviation was associated with the maximum amount of ANS and mentioned deviation indicating significant facial asymmetry.
    UNASSIGNED: Class-II Division-1 malocclusion was the most common type noted and Class III malocclusion was more common in higher grades of nasal septal deviation. Maxillary and mandibular asymmetry worsens significantly with an increase in the grade of nasal septal deviation and is one of the significant factors in causing facial asymmetry.
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