Identification of new regional marker proteins to map mouse brain by 2-D difference gel electrophoresis screening

To screen for new region-specific protein markers we compared the proteome maps of the primary visual and somatosensory areas V1 and S1 in mouse brain using 2-D difference gel electrophoresis (2-D DIGE). Twenty-three protein spots showed a statistically significant difference in expression level between V1 and S1, with 52% appearing more abundantly in V1. Twenty-six proteins were mass spectrometrically identified in 22 spots. To assess the validity of this list of potential areal markers generated by 2-D DIGE, the effective area-specific distribution profile of creatine kinase brain subtype (CKB), a protein with a clearly higher expression level in S1, was monitored with in situ hybridization. The mRNA expression profile of CKB displayed a clear area-specific distribution, which allowed demarcation of S1 and its topographical borders with neighboring neocortical areas. This proteomic study demonstrates the innovative application of 2-D DIGE and MS to select new regional markers for neuroscience research.     

How does brain MRI lesion volume change on serial scans in patients with multiple sclerosis?

Although lesion load changes on conventional T₂-weighted brain magnetic resonance imaging (MRI) scans from patients with multiple sclerosis (MS) are used to monitor the effect of treatment, there is no clear definition of how lesion load changes over years according to the lesion load present at a baseline evaluation. In the present study, we evaluated the relationship between lesion load changes over time and lesion load at a baseline evaluation in a group of untreated patients with MS. We scanned nineteen patients on two separate occasions with a mean interval 16.4 months between the two examinations. In each scanning session, a scan with forty contiguous 3-mm-thick axial slices was acquired. We assessed MRI lesion loads using a semi-automated local thresholding technique. Both a linear (p < 0.0001) and a quadratic component (p = 0.0008) of the baseline volume were significant in describing the follow-up volume. The equation to model this finding was as follows: V_f = β₀ V_b + β₁ (V_b)², where V_f is the lesion volume at follow-up, V_b is the lesion volume at baseline, β₀ = 0.834 (SE = 0.098), and β₁ = 0.014 (SE = 0.003) (mL)⁻¹. Our data indicate that lesion volume changes detectable on serial brain MRI studies from patients with MS are dependent on the extent of lesion burden present on the baseline MRI scans. This finding has to be considered when planning phase III trials.     

Spatial brain networks

The human brain is a wonderfully complex organ characterized by heterogeneous connectivity between cellular and tissue units. This complexity supports the rich repertoire of dynamics and function that is characteristic of human cognition. While studies of brain connectivity have provided important insight into healthy cognition as well as its alteration in psychiatric disorders and neurological disease, an understanding of how this connectivity is embedded into the 3-dimensional space of the skull has remained elusive. In this article, we will motivate the importance of studying the brain as a spatially embedded network, particularly for understanding the rules of its development and alterations to those rules that may occur in neurodevelopmental disorders such as schizophrenia. We will review recent evidence for well-defined wiring rules in the brain, informed by notions of wiring minimization, spatially localized modules, and hierarchically nested topology. We will then discuss potential drivers of these rules in the form of evolution, genetics, energy, and the need for computational complexity. Finally, we will conclude with a discussion of emerging frontiers in the study of spatial brain networks, both in theory and modeling, and their potential to enhance our understanding of mental health.     

脑死亡过程中谷氨酸与场电位的同步检测微电极阵列研究

高浓度胞外K+会引起神经元的去极化、谷氨酸释放、甚至细胞死亡。为研究高浓度K+对在体神经元的影响,采用微机电系统( MEMS)方法制作了一种植入式微电极阵列( MEA),其上包含形状、位置固定的电化学(50伊150μm)和电生理(直径为15μm)检测位点,可同时进行脑内神经递质谷氨酸、局部场电位信号( LFP)双模检测。将这种MEA植入到大鼠纹状体后,给大鼠皮层施加高浓度K+刺激,结果表明,高钾刺激增加了纹状体内谷氨酸浓度,同时抑制了神经电生理活动。这是首次采用双模MEA研究神经元在体死亡过程,结果验证了双模微电极阵列在体检测的可行性,可用于研究脑内神经电化学、电生理的时空关系。     

Altered hemispheric symmetry found in left-sided mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE/HS) but not found in right-sided MTLE/HS

Purpose

The purpose was to investigate the altered hemispheric asymmetry in patients with mesial temporal lobe epilepsy with unilateral hippocampus sclerosis (MTLE/HS).

Materials and methods

This study examined the hemispheric asymmetry of regional gray matter (GM) and white matter (WM) volume among a group of 13 patients with left-sided MTLE/HS, a group of 10 patients with right-sided MTLE/HS and a group of 21 age- and gender- matched healthy controls by optimized voxel-based morphometry (VBM) based on magnetic resonance imaging.

Results

Compared to healthy controls, abnormal asymmetries were detected in the left-sided MTLE/HS patients. The left-sided MTLE/HS patients had more GM asymmetries (L<R) in the temporal lobes, including the inferior temporal gyrus, middle temporal gyrus and parahippocampal gyrus. There was significant asymmetry (L<R) in subcortical WM of the mesial temporal lobe in left-sided MTLE/HS patients. However, no significant difference was detected in terms of GM and WM asymmetry between the group with right-sided MTLE/HS and normal controls.

Conclusion

We should approach hemispheric asymmetry in left- and right-sided MTLE/HS patients differently. The study also demonstrates potential future use of VBM in detecting hemispheric asymmetries and lateralization of brain functions.     

颅脑创伤近红外实时监测技术研究

采用一套专门设计的由微创光纤探头组成的光纤光谱仪生物组织光学参数测试系统,对颅脑创伤的大鼠创伤侧和对照侧进行近红外光谱检测及脑水含量(brain water content:BWC)测定.通过采用Feeney's自由落体撞击法建立大鼠急性局灶性脑挫裂伤模型,以近红外光谱技术和干湿比重法监测伤后脑水肿的变化.实验发现:伤后1 h,伤侧脑组织已发生水肿,伤后24～72 h,伤侧脑水肿达高峰,随后逐渐下降;用脱水剂后,脑水肿情况逐渐好转,随着药物失效,水肿又一次发生.生物组织优化散射系数(Reduced Scat-tering Coefficient:μ's)与Bwc的变化规律一致,有很好的线性相关性,能够较好的反映脑组织水肿程度以及药物脱水效果.证实近红外光谱技术用于颅脑创伤实时监测的可行性,为颅脑创伤的研究提出了一种新技术.     

A Bio-Guided Screening for Antioxidant,Anti-Inflammatory and Hypolipidemic Potential Supported by Non-Targeted Metabolomic Analysis of Crepis spp.

This study was designed to evaluate the chemical fingerprints and the antioxidant, anti-inflammatory and hypolipidemic activity of selected Crepis species collected in Greece, namely, C. commutata, C. dioscoridis, C. foetida, C. heldreichiana, C. incana, C. rubra, and Phitosia crocifolia (formerly known as Crepis crocifolia). For the phytochemical analyses, sample measurements were carried out by using nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography coupled with mass spectrometry (LC-MS). Τhe extracts were evaluated both in vitro (radical scavenging activity: DPPH assay and total phenolic content: Folin–Ciocalteu) and in vivo (paw edema reduction and hypolipidemic activity: experimental mouse protocols). Among the tested extracts, C. incana presented the highest gallic acid equivalents (GAE) (0.0834 mg/mL) and the highest antioxidant activity (IC₅₀ = 0.07 mg/mL) in vitro, as well as the highest anti-inflammatory activity with 32% edema reduction in vivo. Moreover, in the hypolipidemic protocol, the same extract increased plasma total antioxidant capacity (TAC) by 48.7%, and decreased cholesterol (41.3%) as well as triglycerides (37.2%). According to fractionation of the extract and the phytochemical results, this biological effect may be associated with the rich phenolic composition; caffeoyl tartaric acid derivatives (cichoric and caftaric acid) are regarded as the most prominent bioactive specialized metabolites. The present study contributes to the knowledge regarding the phytochemical and pharmacological profile of Crepis spp.