Tactile shape discrimination recruits human lateral occipital complex during early perceptual processing

Neuroimaging studies investigating somatosensory‐based object recognition in humans have revealed activity in the lateral occipital complex, a cluster of regions primarily associated with visual object recognition. To date, determining whether this activity occurs during or subsequent to recognition per se, has been difficult to assess due to the low temporal resolution of the hemodynamic response. To more finely measure the timing of somatosensory object recognition processes we employed high density EEG using a modified version of a paradigm previously applied to neuroimaging experiments. Simple geometric shapes were presented to the right index finger of 10 participants while the ongoing EEG was measured time locked to the stimulus. In the condition of primary interest participants discriminated the shape of the stimulus. In the alternate condition they judged stimulus duration. Using traditional event‐related potential analysis techniques we found significantly greater amplitudes in the evoked potentials of the shape discrimination condition between 140 and 160 ms, a timeframe in which LOC mediated perceptual processes are believed to occur during visual object recognition. Scalp voltage topography and source analysis procedures indicated the lateral occipital complex as the likely source behind this effect. This finding supports a multisensory role for the lateral occipital complex during object recognition. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.     

抗人LOC51255单克隆抗体的制备及亚细胞定位

目的:制备抗人LOC51255单克隆抗体,并构建pDsRed1-C3/LOC51255真核表达质粒,了解LOC51255在人肝癌细胞株HepG2中的亚细胞定位情况,为进一步研究其功能提供实验工具和基础.方法:以纯化的重组蛋白pET28b/LOC51255为抗原,免疫BALB/c小鼠,运用杂交瘤技术制备LOC51255单克隆抗体,并用间接ELISA法和Western blot法对单克隆抗体的特性进行鉴定;通过构建含红色荧光蛋白(pDsRed1)的pDsRed1-C3/LOC51255真核表达质粒,转入人肝癌细胞株HepG2表达重组蛋白,并对LOC51255进行亚细胞定位.结果:成功建立2株稳定分泌抗LOC51255单克隆抗体的杂交瘤细胞株;ELISA检测抗LOC51255单克隆抗体的腹水效价分别为1∶12 800和1∶25 600.2株单克隆抗体的免疫球蛋白亚类均为IgG1.通过Western blot实验证实,2株单克隆抗体均能特异性结合真核细胞内源性LOC51255蛋白.荧光显微镜观察发现LOC51255主要定位于HepG2细胞的细胞浆.结论:成功制备了2株效价高、特异性好的抗LOC51255单克隆抗体,制备的单克隆抗体可用于LOC51255蛋白的鉴定;亚细胞定位分析证实LOC51255主要表达于HepG2细胞的胞浆,为LOC51255的生物学功能研究奠定了基础.     

Global Motion Stimuli and Form-From-Motion Stimuli: Common Characteristics and Differential Activation Patterns

We used functional Magnetic Resonance Imaging (fMRI) to explore the areas underlying the processing of two similar motion stimuli that evoke different types of processing. The results indicated that while form-from-motion (FFM) stimuli activated both lateral occipital complex (LOC) and MT complex (MT+), only the LOC remained significantly activated when contrasted with a global motion stimulus (GMS) with different coherence levels. Because of the large number of common characteristics shared between the stimuli, this contrast enabled us to isolate the regions implicated in form processing. The GMS on the other hand only activated MT+, reaching maximal intensity for low coherence. Overall, these data illustrate how two similar motion stimuli can elicit the participation of different cortical visual regions.     

Pharmacogenetic Influence of LOC387715/HTRA1 on the Efficacy of Bevacizumab Treatment for Age-Related Macular Degeneration in a Korean Population

Purpose

The purpose of this study was to determine the pharmacogenetic effects of complement factor H (CFH) Y402H, LOC387715 and high-temperature requirement factor A1 (HTRA1) genotypes on the treatment of exudative age-related macular degeneration (AMD) by intravitreal bevacizumab injection in a Korean population.

Methods

Seventy-five patients diagnosed with exudative AMD were treated with intravitreal bevacizumab (2.5 mg) monotherapy. All patients received three initial intravitreal bevacizumab injections every four weeks and were then treated "as needed" based on clinical findings, optical coherence tomography and fluorescein angiography during the 12 month follow-up period after the third injection.

Results

The difference in visual acuity improvement among the three genotypes of LOC387715 were statistically significant at six months post-treatment (logarithm of the minimum angle of resolution; TT, 0.346; GT, 0.264; GG, 0.188; p = 0.037). Among the LOC387715 genotypes, the number of additional injections was lower in patients who had the risk T allele (GG, 2.143; GT, 2.000; TT, 1.575; p = 0.064). There was no significant difference between visual acuity and central macular thickness change in the CFH Y402H polymorphism group during the 12 month follow-up period. However, the TC group of CFH Y402H required more additional bevacizumab injections than the TT group (TT, 1.517; TC, 3.363; p = 0.020).

Conclusions

This study demonstrated that different LOC387715/HTRA1 genotypes resulted in different bevacizumab treatment responses on exudative AMD. Patients with the risk allele had an improved treatment response and less need for additional injections. However, patients with the CFH Y402H risk allele needed more additional injections of bevacizumab in order to improve visual acuity. This study illustrates how pharmacogenetic factors may help determine treatment modality and dosing. This could ultimately provide basic data for ''personalized medicine'' in AMD.