Short-term variability in amplitude and motor topography of whole-body involuntary movements in Parkinson's disease dyskinesias and in Huntington's chorea

OBJECTIVES: Clinical observations have noted variability in amplitude of levodopa-induced dyskinesias (LID) in Parkinson's disease (PD) and chorea in Huntington's disease (HD) during the day. However, no studies have examined whether both the amplitude and body location (motor topography) of whole-body involuntary movement (WBIM) varied over short periods of time (seconds or minutes), which may have a distinct and significant effect on how disruptive these WBIM may be. The present study quantified the variability of WBIM amplitude and motor topography in patients with PD having LID and in patients with HD having chorea. PATIENTS AND METHODS: WBIM was quantified using the MotionMonitor magnetic motion tracker system. Five patients in each group were tested in two conditions: sitting and standing. RESULTS: WBIM increased from sitting to standing, more so in choreic patients. WBIM varied from 17% to 102% of total WBIM amplitude. Chorea tended to present with greater variability than LID in absolute terms in the standing condition, but not when the mean WBIM amplitude was taken into consideration. Motor topography of WBIM also varied more in the HD group, but mostly in the seated condition where more limbs were free to move. Neither group expressed any laterality of involuntary movement, with amplitude being equally distributed on both sides of the body. CONCLUSION: Results show significant short-term variability in amplitude of chorea and LID, as well as, variability in location of these involuntary movements, illustrating the complexity of the adaptations required to live and be active with involuntary movements such as HD chorea or PD dyskinesias.     

Microtopography of metal surfaces influence fibroblast growth by modifying cell shape, cytoskeleton, and adhesion.

Stainless Steel (SS), titanium (cpTi), and Ti-6Al-7Nb (TAN) are frequently used metals in fracture fixation, which contact not only bone, but also soft tissue. In previous soft tissue cytocompatibility studies, TAN was demonstrated to inhibit cell growth in its "standard" micro-roughened state. To elucidate a possible mechanism for this inhibition, cell area, shape, adhesion, and cytoskeletal integrity was studied. Only minor changes in spreading were observed for cells on electropolished SS, cpTi, and TAN. Cells on "standard" cpTi were similarly spread in comparison with electropolished cpTi and TAN, although the topography influenced the cell periphery and also resulted in lower numbers and shorter length of focal adhesions. On "standard" microrough TAN, cell spreading was significantly lower than all other surfaces, and cell morphology differed by being more elongated. In addition, focal adhesion numbers and mean length were significantly lower on standard TAN than on all other surfaces, with 80% of the measured adhesions below a 2-microm threshold. Focal adhesion site location and maturation and microtubule integrity were compromised by the presence of protruding beta-phase microspikes found solely on the surface of standard TAN. This led us to propose that the impairment of focal adhesion numbers, maturation (length), and cell spreading to a possibly sufficient threshold observed on standard TAN blocks cell cycle progress and eventually cell growth on the surface. We believe, as demonstrated with standard cpTi and TAN, that a difference in surface morphology is influential for controlling cell behavior on implant surfaces.     

Pterygium‐induced corneal astigmatism

A significant degree of corneal astigmatism can be induced by the encroachment of a pterygium onto a cornea. The pterygium generally causes with‐the‐rule corneal astigmatism that is hemimeridional on the side of the pterygium. There is a significant correlation between the extension of the pterygium onto the cornea and the amount of induced astigmatism. However, there is a poor correlation between pterygium‐induced astigmatism measured topographically and that measured by manifest refraction. Successful pterygium surgery will reduce pterygium‐induced refractive astigmatism and improve visual acuity. This paper outlines the management of a patient with an advanced pterygium, in whom a large degree of corneal astigmatism was induced by the encroachment of a pterygium onto the cornea. Subsequent excision of the pterygium brought about a reversal of the pterygium‐induced corneal astigmatism.     

角膜地形图与散瞳验光散光差异分析

目的观察角膜地形图仪与散瞳验光测得的散光差异。方法以138眼（74例）近视眼为研究对象，角膜地形图仪记录角膜地形图形态、角膜屈光度、角膜散光度；散瞳后应用全自动电脑验光仪结合带状光检影及试镜．确定球镜度数、柱镜度数和轴位。所有数据用SigmaSTAT软件包进行统计学配对t检验。结果二组总的平均散光度，散瞳组为－1．21±0．9D，角膜地形图组为－1．37±0．63D，统计有显著性差异（P＜0．01）；总平均散光轴位：散瞳验光组为100．14°±76．4°，角膜地形图组为96．80°±78．0°，统计无显著性差异（P＞0．05）。结论　角膜地形图仪和散瞳验光记录的散光度有差异性，轴位无显著性差异，在设计屈光性手术时有指导意义。     

Species variation in biology and physiology of the ciliary epithelium: Similarities and differences

Glaucoma is a leading cause of irreversible blindness worldwide. Lowering intraocular pressure (IOP) is the only strategy documented to delay the appearance and retard the progression of vision loss. One major approach for lowering IOP is to slow the rate of aqueous humor formation by the ciliary epithelium. As discussed in the present review, the transport basis for this secretion is largely understood. However, several substantive issues are yet to be resolved, including the integrated regulation of secretion, the functional topography of the ciliary epithelium, and the degree and significance of species variation in aqueous humor inflow. This review discusses species differences in net secretion, particularly of Cl⁻ and HCO₃⁻ secretion. Identifying animal models most accurately mimicking aqueous humor formation in the human will facilitate development of future novel initiatives to lower IOP.     

Topography of event-related potentials elicited by visual emotional stimuli

This experiment was intended to explore the effects of the emotional connotation of stimuli on the hemispheric lateralization. Ten right-handed male subjects (Ss) were presented a set of slides of faces expressing a positive emotion, a negative emotion or emotional neutrality. The ERPs elicited by the face stimuli were recorded from 16 leads and topographic maps of P3 amplitude were created. The results show that when Ss had to discriminate between emotional (target) and neutral (non-target) faces, the main differences were seen predominantly over the right centroparietal area. On the contrary, when Ss had to detect a face particularity not related to the emotional content, the differences betweem target and non-target faces were bilaterally distributed. The present results support the hypothesis that the perception of emotional expressions is processed mainly by the right hemisphere.     

利用背散电子象和金属染色法观察组织和细胞的亚表面结构

本研究利用六胺银染液选择性染色方法和背散电子成象技术，在观察粒细胞、淋巴细胞、小肠上皮细胞在面形貌同时，还观察到这些细胞胞核的形态、大小、以及所在细胞内的位置。这些观察结果提示，利用重金属染液选择性的染色和背散电子成象技术，可能是一种在观察组织和细胞表面同时．观察其亚表面结构的新方法。     

The effects of neurofeedback training on the spectral topography of the electroencephalogram.

OBJECTIVE: To investigate the impact of EEG frequency band biofeedback (neurofeedback) training on spectral EEG topography, which is presumed to mediate cognitive-behavioural training effects. In order to assess the effect of commonly applied neurofeedback protocols on spectral EEG composition, two studies involving healthy participants were carried out. METHODS: In Experiment 1, subjects were trained on low beta (12-15 Hz), beta1 (15-18 Hz), and alpha/theta (8-11 Hz/5-8 Hz) protocols, with spectral resting EEG assessed before and after training. The specific associations between learning indices of each individual training protocol and changes in absolute and relative spectral EEG topography was assessed by means of partial correlation analyses. Results of Experiment 1 served to generate hypotheses for Experiment 2, where subjects were randomly allocated to independent groups of low beta, beta1, and alpha/theta training. Spectral resting EEG measures were contrasted prior and subsequent to training within each group. RESULTS: Only few associations between particular protocols and spectral EEG changes were found to be consistent across the two studies, and these did not correspond to expectations based on the operant contingencies trained. Low-beta training was found to be somewhat associated with reduced post-training low-beta activity, while more reliably, alpha/theta training was associated with reduced relative frontal beta band activity. CONCLUSIONS: The results document that neurofeedback training of frequency components does affect spectral EEG topography in healthy subjects, but that these effects do not necessarily correspond to either the frequencies or the scalp locations addressed by the training contingencies. The association between alpha/theta training and replicable reductions in frontal beta activity constitutes novel empirical neurophysiological evidence supporting inter alia the training's purported role in reducing agitation and anxiety. SIGNIFICANCE: These results underline the complexity of the neural dynamics involved EEG self-regulation and emphasize the need for empirical validation of predictable neurophysiological outcomes of training EEG biofeedback protocols.