康复护理干预有助于颅脑外伤术后偏瘫患者的恢复

为探讨基于康复教育护理团队实施康复护理对颅脑外伤术后偏瘫患者生活能力及神经功能恢复的影响,本研究选取96例颅脑外伤术后偏瘫患者,随机分为对照组与观察组各48例,对照组采用常规护理,观察组应用基于康复教育护理团队的康复护理。通过比较两组干预前后日常生活能力评分(ADL)、Fugl-Meyer运动功能量表(FMA)评分及美国国立卫生院神经功能缺损评分(NIHSS)的变化,采用焦虑自评量表(SAS)及抑郁自评量表(SDS)评定干预前后患者心理状态的变化,并统计两组护理期间并发症发生率。研究发现,干预8周,两组轻度依赖、中度依赖所占比例上升,重度依赖、完全依赖所占比例下降,观察组轻度依赖所占比例高于对照组,完全依赖所占比例高于对照组(p<0.05);干预8周,两组FMA表感觉、运动功能、关节活动度、疼痛、平衡等维度评分均上升,观察组各维度评分上升幅度高于对照组(p<0.05),两组NIHSS评分、SAS评分、SDS评分均降低,观察组上述量表评分低于对照组(p<0.05)。观察组护理期间并发症发生率略低于对照组,但比较差异无统计学意义(p<0.05)。本研究证实,对颅脑外伤术后偏瘫患者采用基于康复教育护理团队的康复护理模式可改善患者日常生活能力、运动功能及神经功能,纠正患者不良情绪。     

基于OPT康复训练联合高压氧治疗对重症病毒性脑炎合并吞咽障碍患儿吞咽功能、脑氧代谢及血清神经损害指标的影响

摘要 目的：基于口腔定位疗法（OPT）康复训练联合高压氧治疗对重症病毒性脑炎合并吞咽障碍患儿吞咽功能、脑氧代谢及血清神经损害指标的影响。方法：选取2015年1月到2022年8月期间南部战区总医院接收的重症病毒性脑炎合并吞咽障碍患儿80例。采用信封抽签法将患儿分为对照组（常规对症治疗、口腔吞咽康复训练的基础上联合OPT康复训练）和研究组（对照组的基础上联合高压氧治疗）,各为40例。对比两组疗效、吞咽功能、脑氧代谢及血清神经损害指标。结果：研究组干预后的临床总有效率高于对照组（P<0.05）。干预后,研究组口腔期、食管期、咽期的吞咽障碍调查表（DDS）评分低于对照组（P<0.05）。干预后,研究组血氧饱和度（SjvO₂）、脑氧摄取率（CERO₂）高于对照组,脑动静脉血氧含量差（Da-jvO₂）低于对照组（P<0.05）。干预后,研究组脑源性神经营养因子（BDNF）高于对照组,髓鞘碱性蛋白（MBP）、中枢神经特异性蛋白（S100β）、神经元特异性烯醇化酶（NSE）、β-内啡肽（β-EP）低于对照组（P<0.05）。结论：重症病毒性脑炎合并吞咽障碍患儿采用OPT康复训练联合高压氧治疗,可显著改善吞咽功能、脑氧代谢、血清神经损害指标水平。     

不同类型缺血性脑血管病血清VCAM-1、MMP-2、TIMP-1的表达及与神经功能缺损的关系分析

摘要 目的：探讨不同类型缺血性脑血管病血清血管细胞粘附分子-1（VCAM-1）、基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶抑制剂1（TIMP-1）的表达及与神经功能缺损的关系。方法：选择2016年1月至2020年1月我院接诊的98例缺血性脑血管病患者为本研究对象,其中脑梗死55例设为脑梗死组,短暂性脑缺血发作组43例,并选择我院同期体检中心健康者50作为对照组,分析三组血清VCAM-1、MMP-2、TIMP-1水平之间的差异及不同神经缺损程度血清VCAM-1、MMP-2、TIMP-1水平、美国国立卫生研究院卒中量表（NIHSS）评分变化情况,及其之间的相关性。结果：脑梗死组血清VCAM-1、MMP-2、TIMP-1水平及NIHSS评分显著高于短暂性脑缺血发作组和对照组,差异显著（P＜0.05）;短暂性脑缺血发作组血清VCAM-1、MMP-2、TIMP-1水平及NIHSS评分显著高于对照组,差异显著（P＜0.05）;重度神经缺损组血清VCAM-1、MMP-2、TIMP-1水平及NIHSS评分显著高于中度神经缺损组和轻度神经缺损组,差异显著（P＜0.05）;中度神经缺损组血清VCAM-1、MMP-2、TIMP-1水平及NIHSS评分显著高于轻度神经缺损组,差异显著（P＜0.05）;相关性分析结果中显示,血清VCAM-1、MMP-2、TIMP-1均和NIHSS评分呈正相关（r=0.603, 0.915, 0.778,P＜0.05）。结论：血清VCAM-1、MMP-2、TIMP-1在缺血性脑血管病患者中表达异常,神经缺损越严重血清VCAM-1、MMP-2、TIMP-1表达越高。     

Agonist-dependent Endocytosis of γ-Aminobutyric Acid Type A (GABAA) Receptors Revealed by a γ2(R43Q) Epilepsy Mutation

GABA-gated chloride channels (GABA_ARs) trafficking is involved in the regulation of fast inhibitory transmission. Here, we took advantage of a γ2(R43Q) subunit mutation linked to epilepsy in humans that considerably reduces the number of GABA_ARs on the cell surface to better understand the trafficking of GABA_ARs. Using recombinant expression in cultured rat hippocampal neurons and COS-7 cells, we showed that receptors containing γ2(R43Q) were addressed to the cell membrane but underwent clathrin-mediated dynamin-dependent endocytosis. The γ2(R43Q)-dependent endocytosis was reduced by GABA_AR antagonists. These data, in addition to a new homology model, suggested that a conformational change in the extracellular domain of γ2(R43Q)-containing GABA_ARs increased their internalization. This led us to show that endogenous and recombinant wild-type GABA_AR endocytosis in both cultured neurons and COS-7 cells can be amplified by their agonists. These findings revealed not only a direct relationship between endocytosis of GABA_ARs and a genetic neurological disorder but also that trafficking of these receptors can be modulated by their agonist.     

Effect of Aluminium on Lipid Peroxidation of Human High Density Lipoproteins

We investigated the effect of aluminium (Al 3+ ) on lipid peroxidation and physico-chemical properties of high density lipoproteins (HDL) isolated from human plasma. Our results demonstrated that Al 3+ enhances lipid peroxidation of human HDL as shown by the significant increase in lipid hydroperoxides in Al-treated HDL with respect to control HDL. The oxidative effect was higher at acid pH (pH 5.5) with respect to pH 7.4. Moreover, a stimulating effect of Al 3+ on iron-induced lipid peroxidation of HDL was demonstrated. The study of the effect of Al 3+ on the physico-chemical properties of HDL, using the fluorescence polarization (Pf) of the probes TMA-DPH (1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene iodide) and DPH (1,6-diphenyl-1,3,5-hexatriene), showed a significant decrease of Pf in Al-treated HDL with respect to control. These results suggest that Al 3+ induces a decrease of molecular order at the lipoprotein surface. Moreover, the study of tryptophan (Trp) fluorescence demonstrated that aluminium induces structural modifications of HDL apoproteins and on HDL physico-chemical properties. The effect of Al 3+ on lipid peroxidation of HDL was observed at aluminium concentrations similar to those observed in the brain of patients affected by neurological diseases. Aluminium-induced oxidative damage of HDL could be involved in the development of neurological diseases.     

Secondary storage of dermatan sulfate in Sanfilippo disease

Mucopolysaccharidoses are a group of genetically inherited disorders that result from the defective activity of lysosomal enzymes involved in glycosaminoglycan catabolism, causing their intralysosomal accumulation. Sanfilippo disease describes a subset of mucopolysaccharidoses resulting from defects in heparan sulfate catabolism. Sanfilippo disorders cause severe neuropathology in affected children. The reason for such extensive central nervous system dysfunction is unresolved, but it may be associated with the secondary accumulation of metabolites such as gangliosides. In this article, we describe the accumulation of dermatan sulfate as a novel secondary metabolite in Sanfilippo. Based on chondroitinase ABC digestion, chondroitin/dermatan sulfate levels in fibroblasts from Sanfilippo patients were elevated 2-5-fold above wild-type dermal fibroblasts. Lysosomal turnover of chondroitin/dermatan sulfate in these cell lines was significantly impaired but could be normalized by reducing heparan sulfate storage using enzyme replacement therapy. Examination of chondroitin/dermatan sulfate catabolic enzymes showed that heparan sulfate and heparin can inhibit iduronate 2-sulfatase. Analysis of the chondroitin/dermatan sulfate fraction by chondroitinase ACII digestion showed dermatan sulfate storage, consistent with inhibition of iduronate 2-sulfatase. The discovery of a novel storage metabolite in Sanfilippo patients may have important implications for diagnosis and understanding disease pathology.     

Cleavage of neuregulin-1 by BACE1 or ADAM10 protein produces differential effects on myelination

Neuregulin-1 (Nrg1) is encoded by a single gene and exists in naturally secreted and transmembrane isoforms. Nrg1 exerts its signaling activity through interaction with its cognate ErbB receptors. Multiple membrane-anchored Nrg1 isoforms, present in six different membrane topologies, must be processed by a protease to initiate a signaling cascade. Here, we demonstrate that BACE1 and ADAM10 can process type I and III Nrg1 at two adjacent sites. Our cleavage site mapping experiments showed that the BACE1 cleavage site is located eight amino acids downstream of the ADAM10 cleavage site, and this order of cleavage is the opposite of amyloid precursor protein cleavage by these two enzymes. Cleavages were further confirmed via optimized electrophoresis. Cleavage of type I or III Nrg1 by ADAM10 and BACE1 released a signaling-capable N-terminal fragment (ntf), either Nrg1-ntfα or Nrg1-ntfβ, which could similarly activate an ErbB receptor as evidenced by increased phosphorylation of Akt and ERK, two downstream signaling molecules. Although both Nrg1-ntfα and Nrg1-ntfβ could initiate a common signaling cascade, inhibition or down-regulation of ADAM10 alone in a co-culture system did not affect normal myelination, whereas specific inhibition of BACE1 impaired normal myelination. Thus, processing of Nrg1 by BACE1 appears to be more critical for regulating myelination. Our results imply that a significant inhibition of BACE1 could potentially impair Nrg1 signaling activity in vivo.     

Extrasynaptic N-methyl-D-aspartate (NMDA) receptor stimulation induces cytoplasmic translocation of the CDKL5 kinase and its proteasomal degradation

Mutations in the X-linked gene cyclin-dependent kinase-like 5 (CDKL5) have been found in patients with epileptic encephalopathy characterized by early onset intractable epilepsy, including infantile spasms and other types of seizures, severe developmental delay, and often the development of Rett syndrome-like features. Despite its clear involvement in proper brain development, CDKL5 functions are still far from being understood. In this study, we analyzed the subcellular localization of the endogenous kinase in primary murine hippocampal neurons. CDKL5 was localized both in nucleus and cytoplasm and, conversely to proliferating cells, did not undergo constitutive shuttling between these compartments. Nevertheless, glutamate stimulation was able to induce the exit of the kinase from the nucleus and its subsequent accumulation in the perinuclear cytoplasm. Moreover, we found that sustained glutamate stimulation promoted CDKL5 proteasomal degradation. Both events were mediated by the specific activation of extrasynaptic pool of N-methyl-d-aspartate receptors. Proteasomal degradation was also induced by withdrawal of neurotrophic factors and hydrogen peroxide treatment, two different paradigms of cell death. Altogether, our results indicate that both subcellular localization and expression of CDKL5 are modulated by the activation of extrasynaptic N-methyl-D-aspartate receptors and suggest regulation of CDKL5 by cell death pathways.     

NDRG4 protein-deficient mice exhibit spatial learning deficits and vulnerabilities to cerebral ischemia

The N-myc downstream-regulated gene (NDRG) family consists of four related proteins, NDRG1-NDRG4, in mammals. We previously generated NDRG1-deficient mice that were unable to maintain myelin sheaths in peripheral nerves. This condition was consistent with human hereditary motor and sensory neuropathy, Charcot-Marie-Tooth disease type 4D, caused by a nonsense mutation of NDRG1. In contrast, the effects of genetic defects of the other NDRG members remain unknown. In this study, we focused on NDRG4, which is specifically expressed in the brain and heart. In situ mRNA hybridization on the brain revealed that NDRG4 was expressed in neurons of various areas. We generated NDRG4-deficient mice that were born normally with the expected Mendelian frequency. Immunochemical analysis demonstrated that the cortex of the NDRG4-deficient mice contained decreased levels of brain-derived neurotrophic factor (BDNF) and normal levels of glial cell line-derived neurotrophic factor, NGF, neurotrophin-3, and TGF-β1. Consistent with BDNF reduction, NDRG4-deficient mice had impaired spatial learning and memory but normal motor function in the Morris water maze test. When temporary focal ischemia of the brain was induced, the sizes of the infarct lesions were larger, and the neurological deficits were more severe in NDRG4-deficient mice compared with the control mice. These findings indicate that NDRG4 contributes to the maintenance of intracerebral BDNF levels within the normal range, which is necessary for the preservation of spatial learning and the resistance to neuronal cell death caused by ischemic stress.