不同病因引起的新生儿高胆红素血症听性脑干反应的特点

目的 探讨不同病因引起的新生儿高胆红素血症的听性脑干反应(ABR)特点及其与临床的关系.方法 将88例(176耳)高胆红素血症患儿按病因分为6组,同时选取15名(30耳)健康新生儿作为正常对照,均进行ABR测试,并比较各组间的差异,42 d后患儿复查ABR.结果 不同病因中,葡萄糖6-磷酸脱氢酶(glucose-6-phosphate dehydrogenase,G-6-PD)缺乏症所致的高胆红素血症ABR反应阈增高最明显,异常率最高.不同病因组之间及与对照组间ABR的Ⅲ波、Ⅴ波潜伏期及Ⅲ-Ⅴ、Ⅰ-Ⅴ波间期差异均具有统计学意义(P值均＜0.05).高胆红素血症患儿ABR各波潜伏期及波间期均较对照组延长,其中新生儿感染最容易引起ABR各波潜伏期及波间期延长,其次是ABO溶血与其他不明原因组,母乳性黄疸组潜伏期与波间期相对要短.多病因组ABR反应阈的异常率明显高于单病因组(P＜0.05);单种病因与多种病因引起的高胆红素血症组间比较,ABR各波潜伏期及波间期差异无统计学意义(P值均＞0.05).30例患儿进行了复查,复查前后除Ⅰ-Ⅲ波间期外,各波潜伏期及波间期差异均具有统计学意义(P值均＜0.05).结论 高胆红素血症对听觉系统的损害与病因的种类及数量有关.由G-6-PD缺乏、新生儿感染、ABO溶血、多病因以及不明原因引起的高胆红素血症与母乳性黄疸相比,更易导致听觉功能损害.高胆红素血症对听觉的损害存在一定的可逆性.

Abstract：

Objective To explore the characteristics of auditory brainstem response (ABR) in neonatal hyperbilirubinemia induced by different causes. Methods A total of 88 neonates ( 176 ears) with hyperbilirubinemia were divided into several groups according to the causes and followed up after 42 d, and 15 nomal neontes (30 ears) were measured ABR and analyzed the results. Results The thresholds of ABR in glucose-6-phosphate dehydrogenase were the highest in all the groups and had the lowdest incidence rate.The wave Ⅲ, Ⅴ latencies and Ⅲ-Ⅴ, Ⅰ -Ⅴ interwave intervals of the ABR were significantly difference and prolonged during test in comparison to the latencies in the control group ( P ＜ 0. 05 ). The neonatal infections group had the longest wave and interwave intervals, followed by ABO incompatibility hemolytic diseases and the unknown cause groups, while the breastfeeding jaundice were the shortest in the groups of neonatal hyperbilirubinemia. The thresholds of ABR in the hyperbilirubinemia caused by several etiologies were significant abnomality when compared with the single etiology. However, they were similar in the wave latencies and interwave intervals of ABR. During the follow up, the ABR wave latencies and interwave intervals except for interwave latency Ⅰ-Ⅲ were significantly shorter. Conclusions The toxicity of hyperbilirubinemia to the auditory nervous system are related to the species and number of etiologies. The neonate hyperbilirubinemia cuased by glucose-6-phosphate dehydrogenase, infections, ABO incompatibility hemolytic diseases and many etiologies are much more dangerous to the auditory system than the breastfeeding jaundice. The damages of hyperbilirubinemia to the auditory nervous system are reversible probably.     

EVALUATION OF AUDITORY EVOKED POTENTIALS FROM THE INFERIOR COLLICULUS IN RAT

This study aimed to investigate the usefulness of auditory evoked potentials (AEPs) in rats. To this end, N1, P2 latencies, and the N1 P2 amplitude of responses to different acoustic stimuli from rats, which were implanted with permanent electrodes in the inferior colliculus (IC), were evaluated and used to demonstrate the frequency characteristics of IC region. Permanent electrodes were implanted in IC regions of 7 male albino rats by the stereotaxic method. The animals were exposed to five tones series of stimuli (1000 Hz, 2000 Hz, 4000 Hz, 6000 Hz, and 8000 Hz tones with 1500 ms interstimulus intervals) of 70 dB with a duration of 1000 ms. AEPs)were recorded and analyzed with the Brain-Data Acquisition system. There were no statistically significant differences in N1, P2 latencies, and the N1-P2 amplitude of AEPs from IC regions of rats as a result of changes in the frequency of stimulus. It was determined that the dominant frequency activity of the IC to acoustic stimulus was theta-alpha band, with theta as the peak frequency. As a result it was concluded that there are similarities between the N1, P2 components of rat AEPs, and human AEPs. We have suggested that the rats may provide a useful model for investigating the generation of middle latency components of AEPs in humans.     

Brainstem auditory response findings in preterm infants after necrotizing enterocolitis

Aim: To examine brainstem auditory function and detect any abnormality at term in preterm infants after neonatal necrotizing enterocolitis (NEC). Methods: Brainstem auditory evoked response (BAER) was recorded at 21/sec and 60 dB nHL in 37 preterm infants who had NEC. The data obtained at term equivalent age were analyzed and compared with those in normal term infants. Results: The threshold of BAER in infants after NEC, though slightly elevated, did not differ significantly from that in the controls. The latencies of waves I and III were slightly longer than in the controls, without any statistical significance. However, wave V latency was prolonged and differed significantly from the controls (p < 0.01). I-V interpeak interval was also prolonged (p < 0.05). The data point distribution of wave V latency and I-V interval was higher in the infants after NEC than in the controls. The amplitudes of BAER wave components in the infants after NEC did not differ significantly from those in the controls. Conclusion: Preterm infants after NEC have no major abnormality in peripheral auditory function. However, neural conduction in the brainstem auditory pathway is abnormal, suggesting that NEC adversely affects brainstem auditory conduction.     

Cerebral Response to Electric Stimulation of the Colon and Abdominal Skin in Healthy Subjects and Patients with Irritable Bowel Syndrome

Background: Visceral hyperalgesia may play an important part in the pathophysiology of the irritable bowel syndrome (IBS). We investigated the neuronal afferent pathways in healthy volunteers and IBS patients by recording evoked potentials (EPs) elicited by electrical stimulation of the colon and abdominal skin inside and outside the referred pain area. Methods: Six healthy subjects and nine IBS patients met the inclusion criteria. Morphology and topography of EPs to painful electrical stimuli were estimated in the rectosigmoid junction and on the skin inside/outside the referred pain areas. Results: The EPs to painful stimuli of the gut showed a shorter latency and a smaller amplitude of the first positive peak (P1) in the IBS group. The controls had a mid-latency frontal positive component after 100 ms, whereas no reliable early activation was seen in the IBS patients. In controls, a single late (> 150 ms) positive component was seen, whereas the late component was biphasic in the IBS group. The EPs to painful stimuli of the two skin areas differed in IBS patients, but not in controls. Conclusion: Differences in the EPs to electrical painful stimulation of the sigmoid colon and skin inside/outside the experimentally evoked referred pain area were seen comparing healthy subjects and IBS patients. The results indicate altered central nervous system responses.     

Neurophysiology of Hungarian subject–verb dependencies with varying intervening complexity

Non-adjacent dependencies are thought to be more costly to process than sentences wherein dependents immediately follow or precede what they depend on. In English locality effects have been revealed, while in languages with rich case marking (German and Hindi) sentence final structures show anti-locality-effects. The motivation of the current study is to test whether locality effects can be directly applied to a typologically different language than those investigated so far. Hungarian is a “topic prominent” language; it permits a variation of possible word sequencing for semantic reasons, including SVO word order. Hungarian also has a rich morphological system (e.g., rich case system) and postpositions to indicate grammatical functions. In the present ERP study, Hungarian subject–verb dependencies were compared by manipulating the mismatch of number agreement between the sentence's initial noun phrase and the sentence's final intransitive verb as well as the complexity of the intervening sentence material, interrupting the dependencies. Possible lexical class and frequency or cloze-probability effects for the first two words of the intervening sentence material were revealed when used separate baseline for each word, while at the third word of the intervening material as well as at the main verb ERPs were not modulated by complexity but at the verb ERPs were enhanced by grammaticality. Ungrammatical sentences enlarged the amplitude of both LAN and P600 components at the main verb. These results are in line with studies suggesting that the retrieval of the first element of a dependency is not influenced by distance from the second element, as the first element is directly accessible when needed for integration (e.g., McElree, 2000).     

Processing of existing,synonymous, and anomalous German derived adjectives: An MEG study

Neuronal activation as response to reading existing derived German adjectives (e.g., freundlich, friendly) was measured using MEG and compared to that evoked by non-existing, but semantically synonymous adjectives (*freundhaft) and to activation induced by non-existing, semantically and morphologically anomalous adjectives (*freundbar). By applying distributed source modeling we revealed a gradual increase of neuronal activity within areas of the left temporal lobe in the time range of the N400. Activity increased from existing over synonymous to anomalous adjectives. Underscoring the use of neurophysiological measures, these results demonstrate that morpho-semantic analysis take place for non-existing morphologically complex pseudowords even if not warranted by the current task. Furthermore, these data argue in favor of morphological decomposition.     

The reflection of retinal light response information onto the superior colliculus in the rat

Background The functional principles of mediation of retina-encoded visual information through the optic nerve to the superior colliculus (SC) of the contralateral brain hemisphere were investigated in non-drugged and unrestrained albino rats by considering the following issues: (1) the type of information transmitted, (2) the response components of the retina and SC involved in encoding the transmitted information, and (3) the timing of related processes. Methods The field potential responses for different intensities of flashes, under different background illuminations, were simultaneously recorded from the sclera area of the eye and the optic layer of the contralateral SC. Results It was found that the b-wave crest of the retinal electroretinogram (ERG) and the peak-1 or peak-2 of the SC correlate by their amplitude, while the a-wave trough of the retinal ERG and the peak-1 of the SC correlate by their latency. The values of these mutually correlating response components were invariably determined by the given light response bias of the retina (photoreceptors), the change in the photon flux of the light stimulus and, obviously, the change in the wavelength of the light stimulus. The a-wave trough, peak-1, b-wave crest and peak-2 were invariably induced in this time-order. Conclusions The data suggest that the information properties of (a) intensity, (b) presentation time and, obviously, (c) colour of the light stimulus, such as are shed on the retina, and information about the light response bias of the retina are mediated correlatively and quantitatively to the cell network system of the SC through the optic nerve. These processes must happen during the a-to-b-wave phases of the ERG. The data indicate that the random-type variations in the activity of the related cellular systems may actually be harnessed in mediating the defined information properties of the visual stimulus from the retina to the SC of the brain through the optic nerve. This study shows a method of measuring the function of the optic nerve. Results of this study have tentatively been presented at the ARVO 2004 meeting. The author has full control of all primary data and agrees to allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review this data if requested.     

CF接口技术在诱发电位测试系统中的应用

本文介绍了一种基于PDA等移动计算平台和CF接口技术的诱发电位测试系统的设计。这种诱发电位测试系统在PDA等移动计算设备的CF接口基础上，设计出工作于10模式的CF＋卡，并编写出运行于Windows CE等移动操作系统平台上的设备驱动程序和数据采集、处理程序，完成诱发电信号的产生和诱发电位的采集。系统对输入的模拟信号进行调理，A／D转换后，进行数字信号处理，处理结果显示在PDA上。本系统硬件设计简洁，软件支持完善，能够满足各种诱发电位生理研究的需要。     

Miller Fisher综合征的肌电图及诱发电位表现

应用肌电图、体感和脑干听力诱发电位对８例ＭｉｌｌｅｒＦｉｓｈｅｒ综合征患儿进行系列检查。发现７例患儿中４例出现复合肌肉动作电位波幅减低伴感觉神经动作电位不能引出，其中２例尚有运动神经传导速度减慢；２例仅有复合肌肉动作电位波幅减低；１例感觉神经动作电位波幅位于低限；３例体感诱发电位和２例脑干听力诱发电位示周围神经性损害。提示本病主要损害周围神经（以感觉神经为重）的轴索并伴有髓鞘脱失。     

Integrating gender and number information in Spanish word pairs: an ERP study

The aim of the current study was to explore the integration processes of gender and number morphological features, since it has been proposed that grammatical gender and number features might be associated with different strength with the word stem in lexical representation. Event related potentials (ERPs) were recorded using a 128-channel sensor net while twenty-four volunteers read Spanish word pairs and performed a syntactic judgment task. The word pairs which could agree or disagree in gender or number or in gender and number at the same time, were formed by a noun and an adjective (e.g. faro-alto [lighthouse-high]). A negativity around 400 msec with posterior distribution, which has been related to lexical integration processes, was found in response to both gender and number violations. No differences were found between gender disagreement, number disagreement and the double disagreement. Therefore, ERPs suggest that integration of gender and number features may not be different, and that the detection of disagreement may work under a binary state, since the double disagreement condition did not differ from the others. In addition, a subsequent component (identified as P3) showed delayed latencies in the gender disagreement condition as compared to the number disagreement condition, while the double disagreement conditions showed a shorter peak latency than the other two disagreement conditions and similar to the agreement condition. The variations in the latency of the P3 component, which has been related to categorization processes, suggest that these processes are quickly triggered by the accumulation of two incongruent as compared to one disagreement features, and that reanalysis is costlier in the case of gender disagreement as compared to the number disagreement.