Melatonin secretion in patients with Parkinson's disease receiving different-dose levodopa therapy

ObjectiveMelatonin is involved in the regulation of sleep and circadian biological rhythmicity; decreased melatonin secretion has been associated with circadian disruptions. Previous studies evaluating melatonin levels between patients with Parkinson's disease (PD) and controls without PD have found conflicting results; however, large-scale studies have not been performed. Our aim is to compare endogenous melatonin levels between patients with Parkinson's disease (PD) and non-PD older adults.MethodsIn this cross-sectional study on 201 outpatients with PD and 380 community-dwelling older Japanese adults (controls), urinary 6-sulfatoxymelatonin excretion was measured to estimate endogenous melatonin levels.ResultsUrinary 6-sulfatoxymelatonin excretion (UME) did not significantly differ overall between PD patients and non-PD controls, even after adjusting for age, gender, medications, sleep habits, and seasons. Among PD patients, a clear and robust dose–response association was found between levodopa equivalent dose and UME, independent of potential confounding factors, including Parkinson's disease severity. Compared with the lowest levodopa equivalent dose quartile group (mean levodopa equivalent dose, 132 mg/day), the highest group (mean levodopa equivalent dose, 973 mg/day) exhibited a 68% increase in UME (17.8 vs. 30.0 ng/mg cre, respectively). In addition, compared with the non-PD controls, PD patients receiving a lower levodopa equivalent dose displayed decreased UME and those receiving higher levodopa equivalent dose displayed increased UME.ConclusionOur study suggests that melatonin levels in PD patients receiving average levodopa doses are comparable with those in older adults, even after considering confounding factors. This association was modulated by daily levodopa dose in PD patients.     

Neuronal correlates of perceptual amplitude-modulation detection

The goal of the present paper is to relate the coding of amplitude modulation (AM) in the auditory pathway to the behavioral detection performance. To address this issue, the detectability of AM was estimated by modelling a single neuron located in the central nucleus of the inferior colliculus (IC). The computational model is based on cochlear nucleus responses and a coincidence detection mechanism. The model replicated the main feature of the neuronal AM transfer function, namely a bandpass function. The IC-unit model was initially tuned to a 200-Hz modulation frequency. A single neurometric function for AM detection at this modulation frequency was generated using a 2-interval, 2-alternative forced-choice paradigm. On each trial of the experiments, AM was taken to be correctly detected by the model if the humber of spikes in response to the modulated signal exceeded the number of spikes in an otherwise identical interval that contained an unmodulated signal. Psychometric functions for 4 human subjects were also measured under the same stimulus conditions. Comparison of the simulated neurometric and psychometric functions suggested that there was sufficient information in the rate esponse of an IC neuron well-tuned in the modulation-frequency domain to support behavioral detection performance.     

用卡托普利治疗肾性高血压山羊模型的血压近日节律分析

作者用计算机辅助自动采样控制贮存的测压系统,对正常山羊及Goldblatt高血压山羊作48小时连续测定动脉血压。用群体均值余弦法分析,发现两者呈相似的血压近日节律波动式样,山羊血压昼低夜高。用卡托普利常规和择时给药两种方式治疗高血压,结果两种给药方式均能降低全天血压,两者降压程度无统计学差异,而择时疗法的药物剂量和给药次数均较少,提示于血压峰值时相前给予半衰期短的药物 对高血压山羊能有效地降低全天动脉血压。     

麻醉家兔急性窒息时膈神经放电和动脉血压的变化

观察了24只麻醉、双侧颈迷走神经切断、肌松和人工通气家兔急性窒息时,呼吸和血压的变比。结果:①积分隔神经活动可分为潜伏期、兴奋期、抑制期和停止期。兴奋期频率加快,血幅增大.抑制期频率减慢,振幅增大。②血压变化分为潜伏期、升压期和降压期.③窒息时首先影向心血管活动.但呼吸中枢衰竭却早于心血管中枢。对其意义进行了讨论。     

改良振幅整合脑电图评分联合血清神经元特异性烯醇化酶水平对新生儿胆红素脑损伤的早期预测价值

目的探讨改良振幅整合脑电图(aEEG)评分联合血清神经元特异性烯醇化酶(NSE)水平,对新生儿胆红素脑损伤的早期预测价值。 方法选择2017年3月至2018年2月,于苏北人民医院新生儿病房住院治疗的80例高胆红素血症新生儿为研究对象。根据头颅MRI检查结果是否有苍白球高信号改变,将其分为脑损伤组(n＝37)及无脑损伤组(n＝43);并选择本院产科同期出生的40例健康足月新生儿为对照组。对3组受试儿进行aEEG监测,并进行改良aEEG评分,检测血清总胆红素(TBiL)浓度及NSE水平,以及脑干听觉诱发电位(BAEP)。对3组受试儿一般临床资料、改良aEEG评分、血清TBiL浓度及NSE水平,采用单因素方差分析及最小显著性差异法(LSD)-t检验,进行总体比较及两两比较;对改良aEEG评分、血清NSE水平及aEEG分度分别与BAEP分度的相关性,采用Spearman秩相关分析法;绘制受试者工作特征曲线(ROC),比较改良aEEG评分、血清NSE水平及二者联合,对高胆红素血症新生儿发生胆红素脑损伤的预测价值。本研究遵循本院伦理委员会所制定的伦理学标准,并得到批准(审批文号：2016KY-064),所有纳入对象监护人知情同意。 结果①3组新生儿性别构成,入院时日龄及胎龄,出生时体重、身长、头围及胸围,以及其母亲孕次、产次比较,差异均无统计学意义(P>0.05)。②脑损伤组新生儿的改良aEEG评分为(7.7±1.6)分,分别低于无脑损伤组及对照组的(10.4±1.5)分和(10.9±1.3)分;而血清TBiL浓度及NSE水平分别为(349.7±74.0) μmol/L、(47.6±13.2) μg/L,均分别高于无脑损伤组的(295.7±31.4) μmol/L、(32.3±7.7) μg/L及对照组的(185.1±35.9) μmol/L、(28.6±7.3) μg/L,并且差异均有统计学意义(均为P<0.001)。③本研究受试儿的改良aEEG评分与BAEP分度呈负相关关系(r_s＝-0.718,P<0.001),血清NSE水平及aEEG分度,均与BAEP分度呈正相关关系(r_s＝0.685,P<0.001;r_s＝0.647,P<0.001)。④改良aEEG评分、血清NSE水平及二者联合,预测高胆红素血症新生儿发生胆红素脑损伤的ROC曲线下面积(ROC-AUC)分别为0.875(95%CI：0.795～0.954,P<0.001),0.853(95%CI：0.769～0.937,P<0.001)及0.938(95%CI：0.861～0.980,P<0.001);3种方法预测脑损伤的敏感度分别为86.5%、62.2%、83.8%,特异度分别为74.4%、93.0%、90.7%。 结论改良aEEG评分联合血清NSE水平,对新生儿胆红素脑损伤的早期预测价值,较单一采用改良aEEG评分或血清NSE水平更高。     

人耳蜗基底膜模型的动力特性有限元数值模拟

目的采用有限元模拟,建立人耳蜗基底膜模型,研究耳蜗结构的动力响应。方法应用有限元方法,利用大型有限分析软件ANSYS求解基底膜简化模型的模态。结果 得到了模型上不同部位产生最大振幅时对应的振动频率。结论 频率不同时,行波传播的远近和最大行波的出现部位不同。振动频率愈低,最大行波振幅出现的部位愈靠近基底膜顶部;相反地,高频率声音引起的基底膜振动,只局限于卵圆窗附近。从一个新的角度验证了行波理论。     

Stimulus Duration And Input-Output Function Of The Different Components Of The Slow Auditory Evoked Potential

The influence of stimulus duration on the components N₁₂₀ and P₂₀₀ of the slow evoked potential was investigated at durations 5, 20, 50, 100 and 250 msec. A strong effect could be observed up to 50 msec. The results are discussed in relation to physiological and psychoacoustic data. A simplification is proposed which makes the test valuable as a clinical tool.     

调节与辐辏因素导致视疲劳的诊断和治疗

视疲劳的临床表现复杂,因其症状的非特异性给临床诊断和病因治疗带来一定的困难.随着对该病的认识深入,发现其病因甚为复杂,并且往往是多因素混合导致发病.如果只是单纯的对症治疗效果并不理想,探寻病因进行对因治疗才是根本的治疗策略.目前已经明确多种因素可导致视疲劳,通过必要的眼科及视光学检查可确保明确且全面的病因诊断.目前针对视疲劳的病因治疗难易不同.一些病因只要去除和矫正就能避免视疲劳,而另一些就显得相对困难,调节和辐辏因素导致的视疲劳即属于后者.另一方面由于调节和辐辏检查的专科性,使得它们在视疲劳中的诊断和治疗具有一定的难度和特殊性.我们对目前调节和辐辏在视疲劳中的诊断和治疗现状进行总结,以期为临床诊治带来帮助.     

Sensory nerve conduction velocities of median,ulnar and radial nerves in patients with vibration syndrome

OBJECTIVE: The present study aimed to clarify the range of involvement for hand-arm vibration syndrome (VS) in the median, ulnar and radial nerves of the hand. METHODS: Sensory nerve conduction velocities (SCVs) for 3 nerves in the hands and arms were examined for 34 patients with VS and 23 age-matched controls. Neuropathy types were classified by possible carpal tunnel syndrome (CTS), Guyon's syndrome and digital neuropathy in three nerves. RESULTS: SCV in the median nerve (middle finger, wrist-elbow) and ulnar nerve (little finger, wrist-elbow), and amplitudes of the median nerve (wrist-proximal and distal parts of the middle finger), ulnar nerve (wrist-proximal and distal parts of the little finger; forearm-proximal part of the little finger; upper arm-proximal part of the little finger) and radial nerve (dorsal side of the hand-thumb) were significantly reduced in VS patients compared with controls. According to subject classifications based on the results of SCV and amplitude of nerve action potential, 52.9% of VS patients displayed multi-focal neuropathy including digital neuropathy, possible CTS and/or Guyon's syndrome. CONCLUSION: These findings suggest that VS affects all three nerves in the hand. According to classification results, the main disorders of peripheral nerves comprise digital neuropathy.