Stimulation by mitogens and neuronal membranes of lymphocytes from patients with motor neurone disease

Stimulation of lymphocytes from motor neurone disease patients by either concanavalin A or PHA was shown to be significantly depressed relative to that from normal controls, as assayed by incorporation of [3H]thymidine or [3H]leucine or by glucose uptake. Corresponding significant differences were not shown by assays based upon incorporation of [3H]uridine or of lactate release. Lymphocytes from 4 out of 14 motor neurone disease patients showed a blastogenic response to membranes from rat spinal cord cells, compared with those from 0 out of 9 normal controls. These results not only suggest the possibility of an impaired cellular immune control in MND patients but also indicate the presence of lymphocytes sensitised specifically to neuronal membrane components.     

三维超声对胎儿体表畸形的诊断价值

目的:探讨三维超声成像在胎儿体表畸形诊断的临床价值。方法:利用三维超声仪对在我院进行产前检查的妊娠20~41周的3241例孕妇、共3277个胎儿进行二维及三维超声检查,统计并比较超声诊断与随访结果。结果:140例各种发育异常胎儿,其中体表畸形胎儿34例,二维超声诊断正确者21例,9例体表畸形胎儿二维超声检查不能作出明确诊断;三维超声进一步检查诊断正确者共30例;二维及三维超声检查误诊1例胎儿足内翻,生后证实正常,漏诊1例耳廓缺失、2例多指畸形,生后随访证实。三维超声对胎儿体表畸形检出的敏感性、特异性及准确性分别为90.91%、99.97%、99.88%;二维超声对胎儿体表畸形检出的敏感性、特异性及准确性分别为63.64%、99.97%、99.60%。结论:三维超声能直观显示胎儿体表结构,三维超声检查诊断胎儿体表畸形的敏感性、特异性及准确性高,是二维超声检查的重要补充,与二维超声联合应用,可提高胎儿体表畸形的检出率。     

评估控制性卵巢刺激中预测卵巢反应性的指标

在辅助生育技术的实施中,控制性卵巢刺激(COS)方案是根据患者情况确定的,在用药剂量和启动时间的掌握上非常重要。由于卵巢本身反应性或基础状态的不同,不同年龄及不同病因的患者有着极大的差异,用量适当可避免因启动剂量过大造成卵巢过度剌激(OHSS),或剂量过少造成低反应,卵泡     

Melatonin‐evoked potentiation of the juvenile rat tail artery neurogenic reactivity depends on degree of the change in the reactivity

Aim: Dependence of the melatonin‐evoked potentiation of the rat tail artery neurogenic reactivity on degree of the change in the reactivity was studied. Method: Electrical field stimulation‐evoked contractile response of the juvenile rat tail artery segment under isometric conditions was recorded. 0.1 μm melatonin was administered after the change in the response produced both spontaneously and by acidification (pH 6.6) or alkalinization (pH 7.8) of the solution. Results: During the course of experiment, the contraction force continuously declined, being reduced by 12 ± 5, 24 ± 7 and 32 ± 6% at 20, 70, and 170 min after beginning of experiment, respectively. Melatonin applied at these time points increased the contraction by 20 ± 5, 41 ± 10, and 48 ± 8%, respectively, relative to control. This increase in potentiating effect of melatonin during the course of experiment was not because of sensitization of the segment to the hormone. Acidosis‐induced considerable decline in neurogenic contraction was counteracted by melatonin, while after alkalosis‐induced augmentation in the contraction the hormone was not effective. Melatonin increased the artery response to 0.1 μm noradrenaline. Conclusion: These data suggest that melatonin can restore an attenuated neurogenic reactivity of the juvenile rat tail artery. The effect is more pronounced with further decrease in reactivity and might be due to a change in sensitivity of the post‐junctional membrane to noradrenaline.     

Deep Brain Stimulation——A new treatment for tinnitus

Intractable tinnitus can lead to serious consequences. Study evidence indicates that the central nervous system is involved in generation and maintenance of chronic tinnitus and that tinnitus and other neurologic symptoms such as chronic pain may share similar mechanisms. Brain ablation and stimulation are used to treat chronic pain with success. Recent studies showed that ablation and stimulation in non-auditory areas resulted in tinnitus improvement. Deep brain stimulation (DBS) may be an alternative treatment for intractable tinnitus and deserves further study.     

Investigation of melt agglomeration process with a hydrophobic binder in combination with sucrose stearate

The melt agglomeration process of lactose powder with hydrogenated cottonseed oil (HCO) as the hydrophobic meltable binder was investigated by studying the physicochemical properties of molten HCO modified by sucrose stearates S170, S770 and S1570. The size, size distribution, micromeritic and adhesion properties of agglomerates as well as surface tension, contact angle, viscosity and specific volume of molten HCO, with and without sucrose stearates, were examined. The viscosity, specific volume and surface tension of molten HCO were found to be modified to varying extents by sucrose stearates which are available in different HLB values and melt properties. The growth of melt agglomerates was promoted predominantly by an increase in viscosity, an increase in specific volume or a decrease in surface tension of the molten binding liquid. The agglomerate growth propensity was higher with an increase in inter-particulate binding strength, agglomerate surface wetness and extent of agglomerate consolidation which enhanced the liquid migration from agglomerate core to periphery leading to an increased surface plasticity for coalescence. The inclusion of high concentrations of completely meltable sucrose stearate S170 greatly induced the growth of agglomerates through increased specific volume and viscosity of the molten binding liquid. On the other hand, the inclusion of incompletely meltable sucrose stearates S770 and S1570 promoted the agglomeration mainly via the reduction in surface tension of the molten binding liquid with declining agglomerate growth propensity at high sucrose stearate concentrations. In addition to being an agglomeration modifier, sucrose stearate demonstrated anti-adherent property in melt agglomeration process. The properties of molten HCO and melt agglomerates were dependent on the type and concentration of sucrose stearate added.     

Cerebrospinal fluid and plasma concentrations of oxytocin and vasopressin during parturition and vaginocervical stimulation in the sheep

Simultaneous blood and cerebrospinal fluid (CSF) samples were taken from conscious sheep before, during and after parturition. Concentrations of plasma and CSF oxytocin were significantly elevated during contractions and particularly at birth. Mean prepartum CSF concentrations of oxytocin were around 55% of those found in plasma but postpartum they were up to 2-fold higher than those in plasma. Plasma concentrations of oxytocin were only significantly elevated, compared to prepartum levels, for 15 min postpartum whereas those in CSF were increased for the whole of the 120 min postpartum sampling period. Plasma, but not CSF, concentrations of arginine-vasopressin (AVP) were significantly raised during contractions and birth, and for 15 min postpartum. During the prepartum period CSF AVP concentrations were 67% of those found in plasma whereas at birth plasma levels were 10-fold higher than in CSF. In a separate experiment it was shown that 5 min of mechanical vaginocervical stimulation also stimulated significant increases in CSF and plasma oxytocin concentrations and in plasma vasopressin. Results support previous work suggesting an important role for central oxytocin release in the postpartum induction of maternal behavior and demonstrate that elevated concentrations of oxytocin in the CSF are present for a greater period than in blood. Elevated plasma AVP concentrations during contractions, birth or vaginocervical stimulation may be stimulated by stress associated with these stimuli.     

A Paradigm for Design of Closed Loop Neuromuscular Electrical Stimulator Control Systems

Abstract: The use of neuromuscular electrical stimulation (NMES) for rehabilitation of gait in spinal patients is widely known. The best results can be obtained with the use of biomechanical sensors and a closed loop NMES system. One of the biggest problems faced in the design of control systems for closed-loop operation, in gait rehabilitation, is the variation of the mechanical conditions during the phases of gait. This work presents a new approach to ease the design of rule-based closed loop systems for operation in conditions such as gait rehabilitation.     

The growth of the second underpotentially deposited silver layer on Pt(100)

The electrodeposition of Ag on Pt(100)-(1 × 1) in perchlorate electrolyte was studied by means of time-resolved in situ scanning tunnelling microscopy (STM) and cyclic voltammetry. One monolayer of Ag is deposited underpotentially (upd) ca. 500 mV positive of the Ag⁺/Ag equilibrium potential. Several millivolts positive of the equilibrium potential, a second well defined upd layer forms. Its growth was observed to proceed via island formation and coalescence. This process occurs in two separate stages that manifest themselves in voltammetric peaks as well as in the STM images.