甲基丙二酸血症脑损伤机制研究进展

甲基丙二酸血症是由于甲基丙二酰辅酶A变位酶或其辅酶腺苷钴胺素缺陷所致的一种遗传性代谢疾病。患者体内甲基丙二酸及其他代谢产物蓄积，造成脑组织损伤，可表现为各种不同程度的智力发育迟缓及严重的神经功能障碍。甲基丙二酸血症的脑损伤机制至今尚不完全明确，目前研究主要集中在：线粒体功能障碍、神经元细胞凋亡、细胞骨架磷酸化改变及髓鞘形成障碍等脑神经结构损伤；神经节苷脂和突触可塑性异常等脑神经发育损伤；以及认知和行为改变等脑功能损伤。     

High level of tubulin microheterogeneity in the mouse brain

Using a high resolution isoelectric focusing method, we have demonstrated a high level of tubulin heterogeneity in mouse brain: 21 isotubulins were identified. Determination of the apparent molecular weight and analysis of the peptide map of each isotubulin species allowed us to identify 7 α and 14 β tubulin subunits. Furthermore, variations in this tubulin population during brain development were confirmed; in particular, an increase in the number of β isotubulins was observed at the beginning of the postnatal period.     

The Extracellular Space in the Edematous Human Cerebral Cortex: An Electron Microscopic Study Using Cortical Biopsies

In a vascular anomaly showing moderate edema, the extracellular space appeared apparently normal, exhibiting a membrane to membrane space of about 20?nm in width. In congenital hydrocephalus, this space appeared notably enlarged and occupied by an electron transparent, nonproteinaceous interstitial edema fluid, due to abnormal accumulation of cerebrospinal fluid. In brain trauma, the distended extracellular space contained either electron-lucid nonproteinaceous or electron-dense proteinaceous edema fluid. Hemorrhagic foci, fibrinoid material, and non-nervous invading cells, such as macrophages and monocytes, were also found. In brain tumors, the widened extracellular space showed electron-dense proteinaceous edema fluid and bundles of fibrinoid material. The enlarged extracellular space found in congenital hydrocephalus, vascular anomalies, brain trauma, and tumors is closely related to the clinical symptoms exhibited by the patients under study.     

脑微损伤的影像学进展

脑微损伤是创伤性脑损伤最常见的类型,然而,其潜在的神经生理机制尚未完全阐明,影响患者的早期诊断、治疗及预后评估。近年来,多项磁共振（MRI）新技术不断地涌现并用于评估脑微损伤,如功能磁共振、灌注MRI、弥散张量成像、定量易感性图谱、T2 mapping等。本研究综述了多模态MRI在脑微损伤中的应用,从不同的角度深入地了解脑微损伤的神经病理机制,有助于提高临床医生对脑微损伤的诊断和治疗。     

Combined age- and trauma-related proteomic changes in rat neocortex: a basis for brain vulnerability

This proteomic study investigates the widely observed clinical phenomenon, that after comparable brain injuries, geriatric patients fare worse and recover less cognitive and neurologic function than younger victims. Utilizing a rat traumatic brain injury model, sham surgery or a neocortical contusion was induced in 3 age groups. Geriatric (21 months) rats performed worse on behavioral measures than young adults (12-16 weeks) and juveniles (5-6 weeks). Motor coordination and certain cognitive deficits showed age-dependence both before and after injury. Brain proteins were analyzed using silver-stained two-dimensional electrophoresis gels. Spot volume changes (>2-fold change, p<0.01) were identified between age and injury groups using computer-assisted densitometry. Sequences were determined by mass spectrometry of tryptic peptides. The 19 spots identified represented 13 different genes that fell into 4 general age- and injury-dependent expression patterns. Fifteen isoforms changed differentially with respect to both age and injury (p<0.05). Further investigations into the nature and function of these isoforms may yield insights into the vulnerability of older patients and resilience of younger patients in recovery after brain injuries.     

肺癌性脑损害患者的脑电地形图分析

本文报道６３例肺癌患者脑损害的临床表现，头颅ＣＴ，ＥＥＧ和ＢＥＡＭ检查结果，其中３１例出现肺癌性非转移性脑损害（Ａ组）；３２例发现脑转移（Ｂ组），分析了肺癌脑损害的脑电变化特点。结果表明，头颅ＣＴ可以确定脑转移病灶的存在，ＥＥＧ和ＢＥＡＭ既可显示肺癌脑转移病灶的脑电变化，还可显示非转移性肺癌性脑损害的存在。     

OCT技术在人脑组织成像中的运用研究

目的研究光学相干层析成像技术（optical coherence tomography,OCT）在新鲜人脑标本上对脑灰质、白质等组织的成像对比,探索其在神经外科的临床应用前景。方法利用OCT设备,对手术切除的影像学未见明显异常的颞叶癫痫病患者的颞前叶脑组织进行OCT扫描成像,并将脑灰质、白质的OCT图像进行比较。结果新鲜人脑组织OCT成像中,灰质较灰暗而光穿透深度较深;自质明亮而光穿透深度较浅。对于大脑表层的成像能辨别出小血管、蛛网膜下腔等结构。结论OCT图像与生物组织学图像高度关联,不同组织的光学特征也明显不同。新鲜人脑标本的OCT成像上,根据信号强度与衰减特征可以非常清楚地区分脑的白质和灰质。在改进OCT的探头设计和进一步提高分辨率后,可以用于指导神经外科手术。     

A comparative immunohistochemical study of calcineurin and S-100 protein in mammalian and avian brains

Summary The cellular and topographic localization of calcineurin and S-100 protein was examined immunohistochemically in the mammalian and avian brain. Calcineurin immunoreactivity in both the avian and mammalian brain was located only in neuronal cells. S-100 protein was localized mainly in the glial and Schwann cells within the mammalian brain. However, in the avian brain, neuronal cells in certain regions such as the paleostriatum primitivum and the cerebellum, as well as other non-neuronal cells, exhibited S-100 protein immunoreactivity. A distinct difference was demonstrated in the macroscopic topographic distribution patterns of S-100 protein immunoreactivity between the mammalian and avian brains, while the patterns of calcineurin distribution were essentially identical. In addition, we provided calcineurin- and S-100 protein-immunocytochemical results for the turtle, frog and fish brain.     

Evolutionary Development of Neural Systems in Vertebrates and Beyond

Abstract

The emerging field of “neuro-evo-devo” is beginning to reveal how the molecular and neural substrates that underlie brain function are based on variations in evolutionarily ancient and conserved neurochemical and neural circuit themes. Comparative work across bilaterians is reviewed to highlight how early neural patterning specifies modularity of the embryonic brain, which lays a foundation on which manipulation of neurogenesis creates adjustments in brain size. Small variation within these developmental mechanisms contributes to the evolution of brain diversity. Comparing the specification and spatial distribution of neural phenotypes across bilaterians has also suggested some major brain evolution trends, although much more work on profiling neural connections with neurochemical specificity across a wide diversity of organisms is needed. These comparative approaches investigating the evolution of brain form and function hold great promise for facilitating a mechanistic understanding of how variation in brain morphology, neural phenotypes, and neural networks influences brain function and behavioral diversity across organisms.     

1200例闭合性颅脑损伤的脑电图分析

报告１２００例闭合性颅脑损伤的脑电图结果：正常４９８例，轻度异常４６１例，中度异常２００例，重度异常４１例，总异常７０２例（５８．５％）。外伤后昏迷时间越长，昏迷程度越重，检查时间越早，脑电图异常率越高，异常度越重；脑电图与病人年龄的关系则不十分密切。     

Energy metabolism in the rat brain in the course of traumatic shock

The concentration of high-energy phosphates (ATP, creatine phosphate), the total content of adenyl nucleotides, and the energy potential of the brain cells did not change significantly in experimental animals after trauma to the soft tissues of the thigh, until the terminal phase. The intensity of glycolysis was increased. In the terminal phase anaerobic processes predominated somewhat over aerobic. The absence of changes in the concentration of high-energy phosphates in the rat brain in traumatic shock is probably associated with centralization of the circulation and it is evidence that no critical exhaustion of energy takes place in the brain.I. I. Dzhanelidze Leningrad Emergency Aid Scientific-Research Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Il'in.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 11, pp. 27–29, November, 1974.     

Brain edema and protein expression of c-Fos and c-Jun in the brain after diffused brain injury

Objective: To investigate brain edema and protein expression of c-Fos and c-Jun in brain after diffuse brain injury, and to investigate the pathological change after brain injury, which may provide evidence for the clinical treatment of diffused brain injury. Methods: Marmarou method was used to establish the diffuse brain injury in rats. Results: After diffused brain injury, brain water content increased at 1 h, reached the peak at 1 d and remained at a high level at 7 d when compared with control group. One day after injury, diffuse subarachnoid hemorrhage was observed in the brain. HE staining showed vascular swelling and bleeding at the cortex and corpus callosum at 1 d. β-APP expression was found at the brainstem, hippocampus, thalamus, corpus callosum and periventricular regions. Pathological examination of ultrathin sections showed evidence edema and fracture of axons at 3 d after brain injury. The brain injury caused severe cerebral ischemia. The c-Fos and c-Jun expression increased at 1 h. The c-Fos expression peaked at 3 h (P < 0.05), then reduced, reached a maximal level again at 3 d (P < 0.05), and reduced significantly at 7 d but remained at a higher level when compared with control group (P < 0.05). The number of c-Jun positive cells peaked at 6 h (P < 0.05), then reduced, reached a maximal level again at 3 d and reduced markedly but still remained at a higher level when compared with control group (P < 0.05). Conclusion: After diffuse brain injury, brain water content and c-Fos/c-Jun expression change over time.     

Utility of in vitro proton magnetic resonance spectroscopy in aetiological characterisation of brain abscesses

Purpose: Brain abscesses often present an aetiological dilemma. Microscopy is insensitive and culture techniques are time consuming. Hence, a new rapid technique in vitro Proton Magnetic Resonance Spectroscopy (¹HMRS) was evaluated for its usefulness in the identification of aetiology of brain abscesses. Materials and Methods: A total of 39 pus specimens from brain abscesses were subjected to in vitro ¹HMRS. These pus specimens were also processed by conventional culture methods. The spectral patterns generated by in vitro ¹HMRS were further correlated with culture results. Results: Pus specimens which showed the presence of anaerobes on culture revealed the presence of multiplet at 0.9 ppm (100%), lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (100%) and succinate at 2.4 ppm (75%). Pus specimens that revealed the presence of facultative anaerobes on culture showed a pattern B, i.e., the presence of lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (88.88%) along with the multiplet at 0.9 ppm (100%). Pattern C was seen in aerobic infection which showed the presence of lactate-lipid at 1.3 ppm (100%) along with the multiplet at 0.9 ppm. Pus from two tuberculous abscesses showed the complete absence of multiplet at 0.9 ppm. Conclusions: We observed in this study that it was possible to differentiate bacterial and tuberculous brain abscesses using in vitro ¹HMRS. Further, it was also possible to distinguish between aerobic and anaerobic brain abscesses on the basis of spectral patterns. In vitro ¹HMRS of fungal and actinomycotic brain abscess are also presented for its unusual spectra.     

The Neuroprotective Effect of Electro-Acupuncture Against Ischemic Stroke in Animal Model: A Review

Background

It is well established that electro-acupuncture can exert neuroprotection in animal experiments. However, the exact mechanism of electro-acupuncture against ischemic stroke is not very clear.

Materials and Methods

Literature retrieval was performed in four databases (OVID, PUBMED, EMBASE, and ISI Web of Science), from respective inception to July 2013.

Results

Series of studies have demonstrated that electro-acupuncture might be a promising method in reducing brain damage after stroke and induce brain ischemic tolerance before stroke through the promotion of angiogenesis, alleviation of the inflammatory response, regulation of the blood brain barrier (BBB), inhibition of apoptosis, and so on. Through these mechanisms, electro-acupuncture may reduce the neural damages associated with stroke.

Conclusion

An awareness of the benefits of acupuncture might lead more patients into accepting acupuncture therapy for the management of patients with ischemic stroke and patients with high risk of ischemic stroke.     

Fluorescence histochemical observations on the distribution of exogenous dihydroisoquinoline in the rat brain

Summary The distribution of fluorescence in the rat brain after i.p. or intracerebral (i.c.) injections of a fluorescent dihydroisoquinoline derivate of dopamine was studied. After low i.p. doses (50 mg/kg of body weight) the fluorescence was totally confined to the capillary endothelial cells in the cerebral cortex, neostriatum, and substantia nigra (SN). After large i.p. doses (500 mg/kg) fluorescent material was also present in the neuropil of all the regions studied and some cells of the cerebral cortex and SN. After injections to the neostriatum or SN fluorescence was observed in the endothelial cells and some small to medium-sized rounded cells in both regions. A conspicious dark area contrasting with the background fluorescence was constantly present around capillaries, and this area was in contact with nonfluorescent multibranched cells of astrocytic type. In fluorescent cells the fluorescence was present both in the cytoplasm and the nucleus.     

Repetitive/temporal hypoxia increased P-glycoprotein expression in cultured rat brain microvascular endothelial cells in vitro

The aim of the study was to investigate whether repetitive/temporal hypoxia up-regulated P-glycoprotein (P-gp) in cultured rat brain microvascular endothelial cells (rBMECs). Cultured rBMECs were used as in vitro blood brain barrier (BBB) model. Cells reached confluence were subjected to temporal hypoxic exposure. Under free-glucose cultured medium, the cells were covered by sterile paraffin oil for 15 min, inducing temporal hypoxic exposure. The hypoxic-exposure was carried out once every day up to 8 days, leading to the repetitive/temporal hypoxia in rBMECs. The cell viability was tested using CCK-8 kit, function and levels of P-gp in the cells were measured using rhodamine 123 uptake and western blot, respectively. It was found that 8-temporal hypoxic exposure induced 1.6-fold increase of P-gp level in cells, accompanied by decrease of cellular accumulation of rhodamine 123. Cellular accumulation of phenobarbital was also decreased. These findings indicated that repetitive/temporal hypoxia may be one of the factors resulting in P-gp overexpression in refractory epilepsy.     

Differential regulation of the growth-associated proteins, GAP-43 and SCG-10, in response to unilateral cortical ablation in adult rats

Synapse replacement after brain injury has been widely documented by anatomical studies in various parts of both the developing and adult nervous system. However, the molecular events that define the specificity of the empirically derived rules of reactive synaptogenesis in different regions of the adult brain remain unclear. In this study we examined the differential regulation of the lesion-induced response of the two growth-associated proteins, superior cervical ganglia-10 and growth-associated protein-43, after unilateral cortex ablation, and determined a hierarchical order for the lesion response from remaining afferent projection neurons originating from the contralateral cortex, ipsilateral thalamus and substantia nigra. We report that in response to unilateral cortex ablation both messenger RNA, by northern blot, and protein, by estern blot, for superior cervical ganglia-10 but not growth-associated protein-43 was increased in the homologous area of the contralateral cortex but not the ipsilateral thalamus or substantia nigra. In addition, the specificity of the superior cervical ganglia-10 response, assessed by combined in situ hybridization and retrograde FluoroGold labeling of striatal afferent neurons, found that superior cervical ganglia-10 messenger RNA was increased prominently in layer V pyramidal neurons of the contralateral corticostriatal pathway but was unchanged in afferent projection neurons from the thalamus and substantia nigra. Furthermore, the increase in both superior cervical ganglia-10 messenger RNA and protein seen at three days postlesion in contralateral corticostriatal neurons coincides in time with the initiation of neurite outgrowth in the deafferented striatum by contralateral corticostriatal axons described in our previous ultrastructural study. However, if cortical input to the striatum was removed bilaterally the lesion-induced response for superior cervical ganglia-10 messenger RNA shifted secondarily to thalamostriatal neurons in the ipsilateral thalamus.

These data provide evidence that superior cervical ganglia-10 and growth-associated protein-43 are differentially regulated in neurons of the contralateral corticostriatal pathway in response to unilateral cortex ablation and suggests that superior cervical ganglia-10 plays a role in the regulation of neurite outgrowth in the adult striatum after brain injury. However, the specific role that superior cervical ganglia-10 may play in reactive synaptogenesis remains unclear. In addition, our data suggest that a hierarchical order exists for the reinnervation of deafferented striatal neurons after unilateral cortex ablation with preference given to homologous axons from the contralateral cortex.     

The neuroanatomy of prematurity: Normal brain development and the impact of preterm birth

Brain development is a complex process of micro‐ and macrostructural events that include neuronal and glial proliferation and migration, myelination, and organizational development of cortical layers and circuitry. Recent progress in understanding these processes has provided insight into the pathophysiology of brain injury and alterations of cerebral development in preterm infants. A key factor of abnormalities in the preterm infant is the maturational stage of the brain at the time of birth. This review summarizes current data on normal brain development, patterns of brain injury in the preterm infant, and the associated axonal/neuronal disturbances that occur in the setting of this injury, often termed encephalopathy of prematurity. Clin. Anat. 28:168–183, 2015. © 2014 Wiley Periodicals, Inc.