经冻存的APA微囊牛肾上腺髓质细胞功能研究

目的观察海藻酸钠-聚赖氨酸-海藻酸钠(alginate-polylysine-alginate,APA)微囊牛肾上腺髓质细胞经液氮冻存前后的微囊形态、细胞活性和儿茶酚胺分泌功能变化。方法APA微囊牛肾上腺髓质细胞(牛嗜铬细胞,bevine chromaffin cell,BCC)的冻存以DMSO为保护剂,冻存采取循序缓慢降温,复苏采取快速复温。通过微囊形态、细胞活性和儿茶酚胺分泌量检测观察细胞功能变化。结果与冻存前相比,冻存复苏后的APA微囊BCC形态及细胞活性无明显变化,儿茶酚胺分泌量约为冻存前的80%。结论经冻存复苏的APA微囊BCC仍然保持了较好的形态、细胞活性和儿茶酚胺分泌功能。     

松果体细胞微囊的组织相容性研究

目的：制备松果体细胞微囊并进行动物移植实验，探讨松果体微囊与宿主体的组织相容性。 方法： 游离并摘取乳鼠松果体，胰酶、胶原酶消化分离获取松果体细胞悬液，体外培养后进行海藻酸钠-多聚赖氨酸-海藻酸钠（APA）微囊化处理，将囊化细胞与空囊植入大鼠体内（腹膜腔、肌间隙）。术后15、30 d回收微囊，采用形态学观察、HE染色、细胞计数、高效液相色谱（HPLC）技术检测并分析回收囊的形态、囊内细胞活性、囊壁炎性浸润及纤维化程度，从而判断APA囊膜在体内的组织相容性及其对松果体细胞的免疫保护效应。 结果： 微囊的腹腔回收率约为85％，15 d回收囊大多囊壁完整，少数有破损，囊外粘附巨噬细胞。随植入时间的延长，炎性浸润逐渐加重，囊壁增厚，同一时段微囊与空囊的回收率、囊壁纤维化程度无显著差异。检测证实，15 d回收微囊仍有褪黑素（MT）分泌功能，但细胞功能迅速下降，30 d回收囊的MT检测呈阴性。 结论： APA微囊有一定的组织相容性，对松果体细胞具备免疫保护作用，囊内细胞生存期约为20 d左右，该时段内细胞能维持生物活性和MT分泌功能。     

静电法制备小微囊包裹成年猪胰岛的实验研究

目的探索用静电法制备小微囊包裹成年猪胰岛细胞.方法用自制的静电微囊发生装置、制备海藻酸钠-多聚赖氨酸-海藻酸钠(APA)微囊(微囊直径<350μm),包裹成年猪胰岛,体外检测APA小微囊猪胰岛生物活性及微囊膜的通透性.结果静电法制备的APA微囊直径300～350μm,大小相对均一.小微囊包裹成年猪胰岛后,每个微囊内可见1～2个胰岛团,表面光滑.囊内胰岛组织学结构完整,体外培养微囊化胰岛素分泌良好,葡萄糖刺激释放明显,显示了良好的细胞活力及微囊膜通透性.结论用我们自制的静电微囊发生装置能制备APA微囊包裹成年猪胰岛细胞,微囊直径300～350μm,表面光滑,囊内猪胰岛生物活性良好.     

不同细胞来源松果体微囊功能特性的比较研究

目的：分析体外培养扩增及直接消化分离的松果体细胞微囊的功能差异，筛选最佳的种子细胞来源。方法：游离并摘取乳鼠松果体，胰酶、胶原酶消化分离获取松果体细胞悬液，将直接消化细胞与体外培养一定时间的松果体细胞同时进行海藻酸钠—多聚赖氨酸—海藻酸钠(APA)微囊化处理，采用形态学观察、细胞计数、高效液相色谱(HPLC)技术检测并分析两种细胞微囊的活性和功能差异。结果：体外培养后囊化的松果体细胞分散良好，细胞增殖旺盛，囊内细胞的褪黑素(MT)分泌功能逐渐恢复；直接消化包裹的细胞分散程度较差，有细胞聚集现象，增殖不明显，分泌功能呈下降趋势。结论：体外培养的松果体细胞与微囊材料组织相容性好，囊内细胞活性和功能均优于直接消化包裹的细胞微囊。     

静电法制备小微囊包裹成年猪胰岛的实验研究

目的　探索用静电法制备小微囊包裹成年猪胰岛细胞。方法　用自制的静电微囊发生装置、制备海藻酸钠 -多聚赖氨酸 -海藻酸钠 (APA)微囊 (微囊直径 <35 0 μm) ,包裹成年猪胰岛 ,体外检测APA小微囊猪胰岛生物活性及微囊膜的通透性 .结果　静电法制备的APA微囊直径 30 0～ 35 0 μm ,大小相对均一 .小微囊包裹成年猪胰岛后 ,每个微囊内可见 1～ 2个胰岛团 ,表面光滑 .囊内胰岛组织学结构完整 ,体外培养微囊化胰岛素分泌良好 ,葡萄糖刺激释放明显 ,显示了良好的细胞活力及微囊膜通透性 .结论　用我们自制的静电微囊发生装置能制备APA微囊包裹成年猪胰岛细胞 ,微囊直径 30 0～ 35 0 μm ,表面光滑 ,囊内猪胰岛生物活性良好     

胰岛移植用免疫隔离微胶囊的牢固度、生物相容性和通透性研究

目的为了探讨用于胰岛移植的海藻酸钠-聚赖氨酸-海藻酸钠（APA）生物膜的免疫隔离效果。方法采用高压静电成囊装置,制备APA微胶囊和微囊化胰岛,微囊直径为0.25～0.55mm;取空微囊,利用恒温振荡仪振荡后测定其破损率;将空微囊移植至小鼠腹腔,分别于不同时间由腹腔中灌洗出微胶囊,记数并观察其形态;取一定量空微囊分别与IgG、BSA和胰蛋白酶孵育,测量其浓度变化确定APA微胶囊的通透性。结果采用高压静电成囊技术制成的APA微胶囊呈球形,大小均匀、表面光滑,具有较好的生物相容性;粒径为0.25～0.35mm的微胶囊其牢固度大于粒径为0.45～0.55mm的微胶囊;葡萄糖、胰岛素等小分子物质能够自由通过微囊膜,胰蛋白酶也可通过,但速度较慢;大分子物质牛血清白蛋白和免疫球蛋白则不能透入APA微囊。结论采用高压静电成囊技术可制备高质量粒径为0.25～0.35mm的微胶囊;这是具有良好免疫隔离性能的APA微胶囊。     

微囊化大鼠松果体细胞的体外培养研究

目的 研究微囊化大鼠松果体细胞在体外的生物活性与功能状态。方法 采用胶原酶、胰酶双消化法获取大鼠松果体细胞并进行APA微囊包裹处理，体外培养细胞包囊，相差显微镜观察包囊及细胞形态，台盼蓝染色、5-HT免疫细胞化学法分析包裹细胞活性及分布，高效液相色谱技术(HPLC)检测囊内松果体细胞的褪黑素(MT)分泌状态及微囊的渗透能力。结果 微囊化松果体细胞存活良好，大多数细胞为5-HT免疫反应阳性，HPLC检测证实微囊化松果体细胞MT分泌功能正常，对肾上腺素能激动剂作用敏感。结论 APA细胞微囊具备良好的渗透能力，松果体细胞经微囊包裹处理后其活性和功能未受影响。     

微囊化牛视网膜色素上皮细胞移植治疗帕金森大鼠的研究

目的： 观察微囊化牛视网膜色素上皮细胞（RPE）移植治疗帕金森病（PD）大鼠的疗效。方法： 酶消化法原代培养牛RPE细胞，纯化、传代后用高压静电微胶囊成型装置制作海藻酸钠-多聚赖氨酸微囊化细胞，将其立体定向移植入6-OHDA大鼠PD模型的右侧纹状体，移植分为NS组、RPE组、空微囊组（APA组）和微囊化RPE组（RPE-APA组）。观察移植后：阿朴吗啡诱导的旋转行为变化、移植侧纹状体中多巴胺和高香草酸含量的变化、移植区HE染色及TH免疫组化染色。结果： RPE-APA组阿朴吗啡诱发的旋转次数在移植后第2周开始减少，减少幅度为39.29％（与APA组相比，P<0.05），至第4周减少更加明显，减少幅度为：56.89％（与第2周相比，P<0.05），改善现象一直持续到第14周。行为学出现改善的大鼠纹状体多巴胺和高香草酸含量的增加同其阿朴吗啡诱发的旋转次数的减少相符合。行为学有改善的大鼠囊内细胞TH染色呈弱阳性，微囊周边的纹状体可见TH阳性纤维密度较APA组高。结论： 微囊化牛RPE细胞对6-OHDA大鼠PD模型有治疗作用，是一种前景良好的新型供体。     

微囊化培养对肝细胞增殖生长和功能表达的影响

背景:前期研究证实,肝细胞在微囊化培养过程中结构形态发生变化,细胞的骨架会发生重排。目的:在前期研究基础上,进一步考察微囊化培养体系对细胞生长和功能表达的影响。方法:采用海藻酸钠-多聚赖氨酸-海藻酸钠微囊化人肝癌细胞系HepG2细胞,通过显微观察、苏木精-伊红染色、MTT实验、Realtime RT-PCR与Elisa实验,检测微囊内细胞的生长形态、细胞团的形态结构、细胞的活性、以及细胞的功能表达情况。结果与结论:HepG2细胞在微囊内聚集成团,以三维方式生长,细胞间连接紧密,与传统的平面培养相比,微囊化细胞的生长速率减慢,但微囊化细胞的功能基因表达水平及白蛋白的分泌量增高,说明海藻酸钠-多聚赖氨酸-海藻酸钠微胶囊所提供的微环境有利于肝细胞类组织的体外构建。结果也提示海藻酸钠-多聚赖氨酸-海藻酸钠微胶囊能够实现肝细胞的体外类组织化培养,有望成为一种更具前景的三维培养模式,应用于癌症治疗、高通量药物筛选以及肝组织工程的研究。     

永生化下颌骨髁突软骨细胞的微囊化研究

为了探讨微囊包裹软骨细胞在软骨组织工程中的适用性 ,根据气流切割原理采用海藻酸钠 -多聚赖氨酸 -海藻酸钠 ( APA)对永生化下颌骨髁突软骨细胞 ( Im mortalized mandibular condylar chondrocyte,IMCC)进行微囊包裹。用倒置显微镜观察、台盼蓝染色、细胞记数、HE染色、免疫组化等方法检测微囊的大小、细胞的生长及微囊内组织的软骨特性等情况。研究发现 ,IMCC可在微囊内存活 ,活细胞率 >80 % ,微囊直径平均 779μm。细胞数量随着培养时间的延长逐渐增多 ,约 2 0 d左右达到平台期 ,细胞在囊内呈簇样生长 ,高表达软骨特异的蛋白多糖和 型胶原。提示 IMCC可在微囊内形成类软骨组织样结构 ,微囊技术适用于包裹软骨细胞     

Peripheral adrenoceptors and serotonin receptors in depression. Changes associated with response to treatment with trazodone or amitriptyline

Changes in platelet and lymphocyte adrenoceptor densities, platelet serotonin uptake and aggregatory response to serotonin were assessed in a group of moderately depressed patients before and during treatment with either trazodone or amitriptyline. Platelet serotonin receptor activity and uptake were lower before the start of treatment in all patients than in those patients responding to treatment. The densities of alpha 2- and beta-adrenoceptors tended to be higher in the patients before treatment and returned to control values after effective therapy. There were no major differences in the biochemical changes between the patients treated with trazodone or amitriptyline. When the biochemical data was correlated with the clinical history of the patients, it was found that only endogenously depressed patients, and not those with non-endogenous depression, had a significantly reduced platelet serotonin uptake rate. In addition, female depressives had a slightly lower platelet 5-HT aggregatory response than males irrespective to the type of depression.     

Active and passive forearm flexor tension patterns in the continuous perceptual-motor task paradigm: The significance of motivation

The psychophysiology of skeletal muscle tension patterns during goal-directed behavior was investigated by using the continuous perceptual-motor task paradigm. Subjects were recruited to form serious-minded and playful extreme groups according to their responses to the Telic Dominance Scale (10 subjects in each group). They all performed a continuous perceptual-motor task 5 times at a ‘slow’ speed followed by a final ‘fast’ task. All performance periods lasted for 150 s. Measures of passive (tonic) and active (phasic) forearm flexor EMG activity were derived. It was concluded that serious-mindedness was significant to a tonic build-up of tension in the passive forearm flexor over the course of task performance. In contrast, the playful state was associated with high phasic response amplitudes in the active forearm flexor contingent upon changing the position of the joy-stick. Training moderated the range of state-specific EMG activation. State measures confirmed that the subjects maintained their state dominance during task performance. Error-scores and scores on felt level of arousal did not discriminate between the groups.     

Cardiovascular and electrodermal responses to simple stimuli in autistic,retarded and normal children

Phasic changes in respiratory period, electrodermal activity (EDA), the evoked cardiac response (ECR), and the vasoconstrictive pheripheral pulse amplitude response (PPAR), were examined in matched groups of autistic, retarded, and normal children, using repeated presentation of simple visual and auditory stimuli. Analysis as a function of group membership and age indicated that respiratory pause and EDA showed habituation in the retarded and normal groups, but not in the autistic group, with no age effects in any group. PPAR and ECR showed no habituation in any group, but within-group age differences, and a higher mean response level for the autistic subjects. The autistic children did not display the diminution of response level with increased age that was characteristic of both the control groups. These effects were obtained across both modalities. Results could not be attributed to between-group tonic cardiac arousal differences, and were interpreted as further indications of diminished sensitivity to reductions in stimulus novelty, as well as developmental delay, in early-onset psychosis.     

Left-right differences in the Hoffmann reflex recovery curve associated with handedness in normal subjects

The relation between handedness and the Hoffmann (H) reflex recovery curve was studied in normal subjects. In right handers, the H response recovery curve from the right leg was significantly lower than that from the left leg. The opposite finding was obtained from the left handers. In mixed handers (ambidexters), there was no significant difference between the recovery curves from the right and left legs. It was concluded that there is a close relationship between handedness and the height of the H response recovery curves from the right and left sides.     

Electrodermal non-responding in schizophrenia: Relationships to attentional,clinical, biochemical,computed tomographical and genetic factors

The purpose of the present study was to examine whether a psychophysiologically delineated subgroup of electrodermally non-responding subjects show deviations in other data domains. Specifically, we examined clinical ratings of psychopathology, cognitive measures of distractibility in short-term memory, family history of schizophrenia, as well as biochemical indices of monoamine and endorphin activity, and measures derived from computed tomography.The non-responders had significantly lower skin conductance level, less spontaneous fluctuations, and a smaller ratio of elicited to spontaneous responses. The non-responders had a significantly higher incidence of schizophrenic relatives than the responders, and tended to show more psychotic symptoms. The two groups did not differ in cognitive distractibility, or in biochemical and computed tomographical measures.     

Brainstem control of sensory information: a mechanism for perception

We have proposed a theory in which pathways ascending from the brainstem reticular formation control sensory centers in the dorsal thalamus and neocortex. We assumed that the sensory messages received at a given level are transformed by a stochastic process, called Alopex, in a way which maximizes responses in central feature analyzers. Perception is seen as a process involving a close cyclic interaction between brainstem and sensory relays. We discuss the specific case of visual information flow and the proposed modification of visual images at the level of the dorsal lateral geniculate nucleus (dLGN). Computer simulations of a simple model, representing the dLGN and reafferent control emanating from the reticular formation, show that sensory features are effectively enhanced and--in the absence of sensory input--quasi-sensory features may be generated by feedback of a simple scalar variable that is formed by the non-linear superposition of the responses of any number of feature analyzers. The model proposes a specific mechanism for such processes as visual imagery, hallucinations, and dreaming, and provides a framework for further studies into the nature of cognitive brain functions.     

EEG activity during cognitive processing: influence of attentional factors

The research draws upon two separate areas of inquiry: that of lateralized electrocorical processing of cognitive material; and that of psychophysiological information processing studies related to foci of attentional demands. Eighteen subjects on each of three separate days were presented with tasks considered to be 'right hemispheric' or 'left hemispheric'. These tasks were paired in a 2 X 2 design with an attentional factor requiring attention to the environment or to internal processing. All subjects received all types of tasks. Bilateral EEG measures were taken from the frontal and parietal areas referenced to linked ears. Major frequency bands were determined by a Fast Fourier Transform (FFT) and appropriate ANOVAs performed. The results suggest that task factors (left vs right hemisphere tasks) and attentional demands (internal vs external) are differentially represented in terms of EEG functioning. In general the higher beta frequencies were more sensitive to the hemispheric tasks demands and the middle frequencies (alpha and low beta) more sensitive to the attentional demands especially in the parietal areas.     

The perception of Necker cube reversal interacts with the Bereitschaftspotential

Subjects observed a reversible figure (Necker cube), and were asked to switch a lever about twice a minute. The direction of the lever switch indicated whether a reversal of the Necker cube was just experienced or not experienced. The Bereitschaftspotential (BP, readiness potential) turned out to be smaller in amplitude but earlier in onset prior to the reversal, especially over fronto-central regions. During another condition a tonic background stimulation (achieved by a radio-play) was introduced. Distraction reduced the BP, mainly when no reversal was reported. The results suggest a dependency of pre-movement potentials from non-motoric, psychological variables.     

Weight gain. A side-effect of tricyclic antidepressants

Body weight and appetite were evaluated in 40 depressed outpatients from a private psychiatric practice who were receiving low-modest doses of tricyclic antidepressants. Amitriptyline (maximum of 150 mg/day), nortriptyline (maximum of 50 mg/day), and imipramine (maximum of 80 mg/day) were given for an average of 6 months of treatment. There was a mean weight increase of 1.3-2.9 lbs/month, which led to an average total weight gain of 3-16 lbs, depending on drug, dose and duration. These weight increases were linear over time and were accompanied by marked increases in the preference for sweets. Ultimately, excessive weight gain was the most common cause of discontinuation of treatment, occurring in one-half of the patients. Significant weight loss occurred upon discontinuation of drug. These findings show that chronic administration of low-modest doses of tricyclic antidepressants frequently cause considerable weight gain and can significantly interfere with the ability to provide long-term maintenance therapy.     

Cardiovascular and respiratory responses to electrical stimulation of the midbrain in the rat

In descending through the midbrains of rats with stimulation electrodes, we have observed some remarkable reversals of pressor and depressor autonomic effects as the electrode was moved from one locus to another. Autonomic effects of stimulating in the midbrain areas that we studied are of special interest because stimulations in some of these midbrain loci have pain-relieving effects (Hosobuchi et al., 1977, 1979; Mayer et al., 1971; Soper, 1976). Our observations of cardiac arrest are of particular concern because of the use that is being made of midbrain electrical stimulation to relieve pain in human patients.