Cerebrospinal fluid concentrations of the complement MAC inhibitor CD59 in multiple sclerosis and patients with other neurological disorders

Rodent oligodendrocytes have a unique susceptibility among glia to the lytic effects of complement, due in part to a deficiency in CD59 (protectin), a key surface inhibitor of the complement membrane attack complex (MAC). The possibility that shedding of CD59 by human oligodendrocytes contributes to complement-mediated oligodendrocyte injury in inflammatory demyelinating disease has been investigated by estimating levels of CD59 in cerebrospinal fluid samples from 12 patients with demyelinating disease of the central nervous system and 13 with other neurological diseases. No significant differences were found between patients and controls, or between patients with active and those with clinically inactive demyelinating disease, providing no direct support for oligodendrocyte shedding of CD59 in multiple sclerosis.     

Drug transport across the blood — brain barrier II. Experimental techniques to study drug transport

This is part II of a review on the transport of drugs across the blood-brain barrier. In this part, the emphasis is on the various experimental techniques that can be used to characterize the blood — brain barrier transport of drugs. Generally speaking, three approaches can be distinguished:in vitro techniques using isolated brain capillaries, cerebrovascular endothelial cells in primary culture or endothelium-derived cell lines;in vivo techniques (both single-passage and multi-passage techniques) andin situ perfusion techniques. Each of these techniques has specific advantages and disadvantages associated with it. Therefore, in many instances, a combination of different approaches is needed to study the fundamental aspects of drug transport across the blood-brain barrier.     

小儿脑脊液中生长抑素含量的测定及其临床意义

本文在国内首次应用RIA法测定了43例患神经系统疾病的患儿和23例正常小儿CSF中SS水平。结果表明,正常小儿CSF SS含量为141.63±8.77Pg/ml;癫痫和炎性疾病组SS含量无明显改变。而在脑实质损害组,SS含量明显升高。GSF中SS含量与蛋白含量呈明显正相关。     

脑脊液渗透浓度测定在小儿急性脑水肿治疗中的应用和意义

目的　探讨脑脊液渗透浓度监测在急性脑水肿患儿中的作用及其与预后的关系。方法　收集 5 6例诊断为急性脑水肿患儿的脑脊液标本共 115例次 ,同时采集血液做渗透浓度测定行相关分析。选择小儿正常脑脊液标本共 2 1例作为本方法测定的正常参考值。使用美国产微量渗透压仪 (Model 330 0 )测定渗透浓度。结果　① 2 1例小儿正常脑脊液参考值为 (2 84 8± 8 7)mmol/L ,5 6例急性脑水肿患儿共 115例次脑脊液标本渗透浓度范围 2 5 3～ 35 3mmol/L ;② 10例不同急性脑水肿患儿同一时间的血和脑脊液渗透浓度分别为 (2 92 2± 2 3 6 )mmol/L和 (2 90 4± 2 7 5 )mmol/L ,两者具有高度正相关 (r =0 933,P <0 0 1) ;③ 5例死亡患儿 (共 11例次 )的脑脊液渗透浓度为 (334 8± 16 5 )mmol/L ,与正常参考值比较差异有非常显著性意义 (P <0 0 1) ;当脑脊液渗透浓度超过 32 0mmol/L时 ,病死率明显增加 ;④结脑患儿治疗前脑脊液渗透浓度值为 (2 6 5 4± 11 1)mmol/L ,较正常参考值明显下降 ,差异有显著性意义 (P <0 0 5 ) ;经治疗后脑脊液渗透浓度上升至 (2 80 2± 15 9)mmol/L ,与治疗前比较差异有显著性意义 (P <0 0 5 )。结论　①脑脊液与血渗透浓度具有高度相关性 ,故临床上可用血液替代脑脊液进行渗透浓     

Chlordiazepoxide injection elevates the NaCl solution acceptance-rejection function

Injection (SC) of chlordiazepoxide (2-8 mg/kg) increased the intake of NaCl solution (0.5-3.0% NaCl) as well as water in water-deprived rats when these fluids were made available singly during daily 1-hr rehydration periods. The marked enhancement of this drug effect when NaCl solution was the available fluid does not appear to be due to the induction of a sodium appetite or the mimicking of an increase in water deprivation. The exaggeration of the drug effect when an NaCl solution is the drinking fluid, as opposed to water, may be useful as a sensitive index of action for punishment-attenuating (anxiolytic) drugs.     

An integrative approach to intracranial hydraulic physiology. I. Basic concepts, pressure-volume relationships, and infusion studies

A computer simulation of the anatomy of the intradural fluid compartment is used to explore intracranial hydraulic physiology. It examines the mutual interactions of fluid flow rates, volumes, and pressures that control the physiology of the intracranial fluid. The mechanisms of change in intracranial pressure despite the fixed volume constraint are elucidated. The physical origins of the pressure-volume curve and data on the infusion of cerebrospinal fluid are examined. The dynamic behavior of this passive system closely simulates the observed physiologic response to bolus infusion, constant rate infusion, hypercapnia- hypocapnea , and hydrocephalus.     

Nerve growth factor depletion by autoimmunization produces thermal hypoalgesia in adult rats

Nerve growth factor (NGF) plays a role in mechanisms of inflammation and hyperalgesia in adult animals. We sought to determine if NGF depletion produced by autoimmunization of adult rats altered their thermal sensitivity to an acute noxious thermal stimulus. Anti-NGF IgG was not detected in the cerebrospinal fluid of any tested samples. Only those rats with the highest anti-NGF serum titers showed significant (P<0.05) thermal hypoalgesia measured using the hot plate test (52°C): the mean (±S.D.) hind paw lick latency of rats in the high anti-NGF titer group was 18.0±4.6 s compared to means of 10.8±4.3 s, 9.2±2.6 s and 10.1±3.0 s in the medium, low and control groups, respectively. Thus, NGF depletion by autoimmunization is a useful model for investigating the role of NGF in behavioral responses of adult rats to noxious stimuli, providing high titers of antibody are present.     

Amino acid transport across the human blood-CSF barrier. An evaluation graph for amino acid concentrations in cerebrospinal fluid

The correlation of cerebrospinal fluid (CSF)/serum concentration quotients was used as a method for identification of amino acids which are transported by a common carrier system across the blood-CSF barrier. Isoleucine, leucine, valine, phenylalanine, tyrosine and lysine were found to compete for the same carrier system. This group of amino acids in man was found to be different from the system described as a neutral amino acid carrier at the blood-brain barrier in rats. In man, methionine and tryptophan do not compete with the other neutral amino acids for the same carrier system. In contrast, lysine as a basic amino acid is found to be correlated with the same transport system as the five neutral amino acids. A graph for the evaluation of pathological amino acid concentrations in CSF is presented. Patients with a blood-CSF barrier dysfunction for proteins showed partly normal, partly increased, CSF/serum concentration quotients for the amino acids. Hydroxyproline could be identified as a constituent of the amino acid pool in CSF. For proline and hydroxyproline a special control system has to be suggested because of their smaller biological variance in CSF than in blood. Contrary to the other amino acids proline and hydroxyproline have a smaller biological variation in CSF than in serum.     

Immunoglobulin prophylaxis in shunt infections: a prospective randomized study

Cerebrospinal fluid shunt infection is serious and one of the most frequent complications of shunt implantation. Age has been one of the most significant host factors for the development of shunt infections. A relative deficiency of the immune response against bacteria in infants could partly explain the higher infection rate in the very young patients. This prospective-randomized study was conducted in two groups: group A (immunoglobulin group) and group B (control group). There were 30 patients in each group. The patients in group A received intravenous immunoglobulin (Sandoglobulin^®) at a dose of 1 g/kg in the night before surgery. Each patient was followed up to 6 months. No infection was seen in group A. In group B, infection rate per procedure and infection rate per patient were 5.1% (P=0.494) and 6.6% (P=0.492), respectively. Intravenous immunoglobulin prophylaxis in infants seems to reduce the shunt infections.     

The significance of age, sex, and cerebrospinal fluid pressure in post-lumbar-puncture headache

In this study of 300 neurological inpatients aged between 18 and 60 years the incidence of post-lumbar-puncture headache (PPH) was 37.3%. The more severe the headache, the more frequently it was associated with dizziness, nausea, vomiting, and tinnitus. If PPH occurred during the first day after lumbar puncture (LP), it was more severe, and lasted longer than PPH, which started later. The incidence of PPH and associated symptoms decreased with increasing age, and was much higher in females than males. The sex difference was nearly exclusively explained by a marked preponderance of PPH in females below 40 years of age, i.e. women in the fertile age. Furthermore, there was a decreased incidence of PPH and associated symptoms in patients with an initial higher than average cerebrospinal fluid (CSF) pressure (162 mm H2O). All these differences were statistically significant. Particularly high frequencies of PPH were found in young women with an initial CSF pressure lower than mean.