海洛因依赖者静息态下低频振幅及相关功能网络的 fMRI 研究

目的：采用静息态下低频振幅(ALFF)与功能连接的方法,观察长期使用海洛因对大脑相关脑区局部神经元的基线活动影响,并分析这些相关脑区神经活动改变与大脑功能组织模式的关系。方法采集17例海洛因依赖者和15例正常被试者的 fMRI 数据,分析海洛因依赖者 ALFF 的变化及其与使用海洛因的关系。以产生差异脑区为感兴趣区,用功能连接方法分析海洛因依赖者功能连接的改变。结果与对照组相比,海洛因依赖者的右侧尾状核、右背侧前扣带回、右额上回的 ALFF 明显降低,而双侧小脑、左颞上回和左枕上回 ALFF 增加。以上脑区中,仅右侧尾状核的 ALFF 值与海洛因使用总时间及每日剂量呈负相关。功能连接分析显示右侧尾状核和背外侧前额叶皮层(dlPFC)的功能连接降低,与小脑的功能连接增强。结论海洛因依赖者基线水平大脑神经元ALFF 减少伴随着大脑功能连接的失调;慢性海洛因依赖者前额-纹状体环路和前额-小脑环路功能失调,后者支持小脑内部模型理论以及促成成瘾者从机械行为向成瘾习惯的转换。     

慢性海洛因依赖患者前额叶皮质功能连接变化的fMRI研究

目的 通过分析慢性海洛因成瘾者认知抑制性控制环路的关键脑区-前额叶功能连接的变化,探讨其在成瘾中的作用.方法 慢性海洛因依赖男性患者12例,与之年龄、受教育程度和尼古丁依赖水平匹配的健康被试12例参加本研究.采用3.0 T磁共振扫描仪,8通道头线圈,对被试分别进行头颅结构和静息态功能磁共振扫描,后利用SPM8软件以双侧前额叶为感兴趣区,分别进行组内和组间前额叶静息态功能网络分析.结果 与对照组比较,慢性海洛因依赖组前额叶与额眶回、角回、颞中回、双侧苍白球功能连接度显著上升,与前扣带回的功能连接显著下降(t=3.5,P<0.001;连续体素显示个数>5).结论慢性海洛因依赖者认知抑制性控制功能的神经环路受损,而奖赏以及动机驱动环路功能出现异常强化.     

长期强制戒断的海洛因依赖者对毒品线索反应的fMRI研究

目的 探讨长期强制戒断对海洛因依赖者在毒品线索条件下渴求及大脑反应的影响.方法 18名经过长期强制戒断的海洛因依赖者及20名年龄、受教育程度相关匹配的健康受试者参加本研究.本研究采用事件相关的实验范式,利用3.0T磁共振设备采集功能数据,并利用SPM 8及SPSS 16.0软件进行大脑激活区差异分析及渴求变化分析.结果 长期强制戒断的海洛因依赖者在毒品线索条件下主观渴求无明显变化(t=1.51,P=0.15).与健康对照组相比,强制戒断组在毒品线索＞中性线索条件下明显激活的脑区包括条件/记忆相关脑区(右侧杏仁核、海马旁回)及视觉空间注意力相关脑区(双侧额下回,左侧顶上小叶).结论 长期强制戒断可能有利于海洛因依赖者保持低的渴求水平,但海洛因依赖者对毒品相关线索的学习性反应可能长期存在.     

毒品线索下美沙酮维持治疗的海洛因依赖者渴求及大脑反应的fMRI研究

目的 探讨美沙酮维持治疗的海洛因依赖者在毒品相关线索条件下的主观渴求变化及大脑功能变化.方法 14名接受美沙酮维持治疗的海洛因依赖者与15名人口学相匹配的健康被试者参加本研究.本研究采用事件相关的线索诱导反应范式,利用3.0T磁共振设备采集功能数据,并利用SPM8及SPSS16.0软件进行大脑激活区差异分析及相关分析.结果 美沙酮维持治疗的患者在毒品相关条件下主观渴求明显升高(t=5.51,P=0.03).与健康组相比,美沙酮维持治疗组在毒品-中性线索条件下明显激活的脑区包括双侧前、中、后扣带回皮层、背外侧前额叶皮层、额内侧回皮层、楔前叶、丘脑以及右侧眶额回、海马和顶下小叶.同时,右侧眶额回的激活程度与接受美沙酮维持治疗的时间呈明显负相关(r = -0.54,P=0.04).结论 尽管接受长期美沙酮维持治疗,海洛因依赖者吸食海洛因造成大脑神经系统的适应性改变可能会长期存在.     

海洛因依赖者巨细胞病毒感染的研究

调查了 15 2例海洛因依赖者吸毒方式及巨细胞病毒 (CMV)感染情况 ,结果显示 :CMV总感染率为 15 79% ,静脉吸毒者与非静脉吸毒者相比 ,感染率无显著性差异 (P >0 0 5 )。研究认为尽管吸毒者是CMV感染的高危人群 ,静脉吸毒以及注射器不消毒或与他人共用注射器、稀释毒品溶剂不消毒等不是造成CMV感染的主要原因 ,而吸毒引起机体免疫力低下可能是巨细胞病毒感染的主要危险因素。     

强制戒断的海洛因成瘾者默认功能网络fMRI研究

目的 探讨强制戒断的海洛因成瘾者默认功能网络的异常.方法 15例经强制戒断的海洛因成瘾者与15例年龄、受教育程度相匹配的健康受试者参加本研究.采用3.0 T磁共振扫描仪进行静息态fMRI数据采集.用SPM8及GIFT软件分别进行数据预处理和独立成分分析以得到默认功能网络.用SPM8比较2组间默认功能网络差异.结果 与健康受试者相比,海洛因成瘾者默认功能网络与抑制性控制相关脑区(双侧前扣带回、内侧前额叶),动机驱动相关脑区(右侧眶额回)以及左侧颞下回及小脑的功能连接度明显下降.未发现与海洛因成瘾者默认功能网络功能连接增强的区域.结论 经过长期强制戒断的海洛因成瘾者大脑默认功能网络仍存在异常.抑制性控制及动机驱动相关脑区受损可能是海洛因成瘾者难以戒断的原因.     

海洛因依赖者脑灰质体积的VBM研究

目的探讨海洛因依赖对大脑灰质结构的作用,分析吸食海洛因总时间、吸食海洛因总量、每日吸食海洛因量等因素对脑灰质体积产生的影响。资料与方法采用MRI对17例海洛因依赖者和15名健康受试者行3D结构像扫描,所得数据用基于体素的形态学分析(voxel based morphometry,VBM)方法分析脑灰质体积,并比较两组之间的体积差异;分析脑灰质体积与吸食海洛因总时间、吸食海洛因总量、每日吸食海洛因量之间的相关关系。结果与健康被试者相比,海洛因依赖者右侧眶额回、中央前回、左侧岛叶、扣带回、枕叶舌回灰质体积减少(P<0.005);控制年龄、受教育程度、每日吸烟量后,脑灰质体积变化与使用海洛因总时间、海洛因总量、每日吸食海洛因量之间无显著相关关系。结论长期吸食海洛因导致脑灰质结构损害,主要涉及认知控制、情感、视觉控制等相关脑区。     

海洛因依赖者肝炎病毒及HIV感染情况研究进展

我国是肝炎的高发区,随着各地区海洛因滥用人数不断增加,与之相关的并发症也愈发突出,     

正常人工作记忆的事件相关fMRI研究

目的:采用事件相关fMRI,探讨正常人工作记忆资源募集和干涉解决的神经基础。方法:采用Sternberg范例的一个亚型工作记忆选择任务,对正性和负性反应试验、低度熟悉负性试验和高度熟悉负性试验进行比较。结果:与正确正性反应相比,一些额叶区域,如扣带回前部(BA32)、额中回(双侧BA46、左侧BA9)、左侧额下回(BA44/45)以及右侧楔前叶(BA7)、右侧顶内沟前部(BA40)在做出正确负性反应时激活增加。与低度熟悉负性试验相比,高度熟悉负性试验中左侧额下回(BA44/45)、右侧楔前叶(BA7)、扣带前部(BA32)激活显著增加。结论:在工作记忆负性反应中需要募集更多的资源。额叶皮层和楔前叶可能是干涉解决的神经底物。     

海洛因依赖者前额叶皮质及杏仁核1H-MR波谱研究

Objective To explore the characteristic findings of 1H-MR spectroscopy(1H-MRS) in the prefrontal cortex and amygdala of patients with heroine dependence(HD), and the relationship to total cumulative dose of inhaled heroine.Methods Fourteen male HD patients and 12 healthy controls (HC) underwent 1H-MRS at the prefrontal cortex and amygdala regions.The total cumulative in haled heroin dose was (852±341) g in HD.Ratios of N-acetylaspartate/creatine(NAA/Cr) and choline/creatine (Cho/Cr) were respectively measured in the prefrontal cortex and bilateral amygdale regions.The student's t test and the linear correlation were employed for statistical analysis.Results Compared to HC group, HD patients had a significant lower ratio of NAA/Cr in the prefrontal cortex (1.44±0.46 vs 1.50±0.75, t=1.77 ,P <0.05), left amygdala region (1.32±0.08 vs 1.42±0.08, t=3.41, P < 0.05), and right amygdala region (1.34±0.09 vs 1.44±0.10, t=2.63, P <0.05), the HD patients had a significant increased ratio of Cho/Cr in the prefrontal cortex (0.92±0.06 vs 0.86±0.08, t=2.31, P < 0.05), left amygdala region (1.20+0.12 vs 1.07±0.04, t=3.60,P<0.05) and right amygdala region(1.26±0.15 vs 1.12±0.11,t=2.60,P <0.05).There was a negative linear correlation between the total cumulative inhaled heroine dose and the ratio of NKA/Cr in the prefrontal cortex (r=-0.9159, P < 0.01), left amygdala region (r=-0.8756, P < 0.01), and right amygdala region (r=-0.9399, P < 0.01) respectively.Conclusions The study indicates that neuronal damage and glial proliferation may occur in the prefrontal cortex and amygdala region, which suggests the abnormalities of executive function and emotion in patients with HD.A relationship exists between the heroin-induced metabolic abnormality and the total cumulative dose of inhaled heroine.     

Comparison of TCA and ICA techniques in fMRI data processing

PURPOSE: To make a quantitative comparison of temporal cluster analysis (TCA) and independent component analysis (ICA) techniques in detecting brain activation by using simulated data and in vivo event-related functional MRI (fMRI) experiments. MATERIALS AND METHODS: A single-slice MRI image was replicated 150 times to simulate an fMRI time series. An event-related brain activation pattern with five different levels of intensity and Gaussian noise was superimposed on these images. Maximum contrast-to-noise ratio (CNR) of the signal change ranged from 1.0 to 2.0 by 0.25 increments. In vivo visual stimulation fMRI experiments were performed on a 1.9 T magnet. Six human volunteers participated in this study. All imaging data were analyzed using both TCA and ICA methods. RESULTS: Both simulated and in vivo data have shown that no statistically significant difference exists in the activation areas detected by both ICA and TCA techniques when CNR of fMRI signal is larger than 1.75. CONCLUSION: TCA and ICA techniques are comparable in generating functional brain maps in event-related fMRI experiments. Although ICA has richer features in exploring the spatial and temporal information of the functional images, the TCA method has advantages in its computational efficiency, repeatability, and readiness to average data from group subjects     

下一代测序数据的质量控制研究

目的：对下一代测序数据质量控制的几个主要问题进行分析,设计数据清理和质量控制软件,为下游的数据分析提供保障。方法基于Bioconducter 软件包,开发了一个数据清理软件（ Fastq_clean ）。结果该软件在一组已发表的菊花转录组数据集上测试,得到了清理后的测序数据,同时输出了质量控制信息。结论该软件在充分利用Illumina序列特征的基础上,可以非常精确地去除低质量残基、接头、rRNA和病毒等污染,最大限度保留了高质量数据。     

Visual analysis of variance: A tool for quantitative assessment of fMRI data processing and analysis

Analysis of variance (ANOVA) is widely used for the study of experimental data. Here, the reach of this tool is extended to cover the preprocessing of functional magnetic resonance imaging (fMRI) data. This technique, termed visual ANOVA (VANOVA), provides both numerical and pictorial information to aid the user in understanding the effects of various parts of the data analysis. Unlike a formal ANOVA, this method does not depend on the mathematics of orthogonal projections or strictly additive decompositions. An illustrative example is presented and the application of the method to a large number of fMRI experiments is discussed. Magn Reson Med 46:1202–1208, 2001. © 2001 Wiley‐Liss, Inc.     

放射剂量测量的远程控制和数据处理

目的 解决中子-γ混合辐射场只能近距离测量与测量人员因不能远离辐射场而可能受到泄漏中子和γ射线照射的问题，并提高测量效率和精度。方法 开发并利用远程控制技术，通过深入剖析6517A静电计中固化的各种控制、采样和通讯命令，利用计算机通过RS-232串行通信接口远程对剂量仪进行控制，在测量完成的第一时间取回测量数据并可通过网络共享这些数据。结果 通过计算机编程，首次实现本地计算机对6517A静电计的完全自动控制，并通过远程计算机对本地计算机的控制来设置并驱动6517A静电计完成剂量测量任务，实现人员对仪器的异地操作。剂量测量全过程不需要测量人员到现场，从而使测量人员免受泄漏射线的照射。结论 本课题首次将远程控制的概念引入以前一直只能近距离进行的放射剂量测量领域，在保证工作质量的同时保护了测量人员的安全与健康。     

Design and implementation of an electronic data recording and processing system for physics quality control checks in external beam radiotherapy

Quality control (QC) of external beam radiotherapy equipment ensures that commissioning performance is maintained. Paper based data recording is still used for QC, but this is resource intensive in terms of data calculation and processing. Electronic systems of data recording have many advantages; for example, they facilitate the analysis of data on a regular basis, allowing the user to examine the "health" of each machine; they help review and audit local frequencies of each check and can possibly predict component failure. They also allow for secure calculation of results and automatic charting for routine trend analysis. Initially, data recording at our centre was paper-based for daily, weekly and monthly checks. This paper system has been successfully replaced with an electronic system for QC data recording and processing for linear accelerators and superficial units. The system makes use of personal digital assistants and networked laptops for online recording of data, and networked desktop PCs for offline work. The systems of data recording have been designed using the power of macros within Microsoft Excel, which automatically calculate each QC parameter and charts the data recorded for long-term analysis of trends. As of the beginning of 2006, these systems have been fully implemented. The benefits of implementing such a system are numerous, for example, central storage, backup and archiving of data, for greater security and reducing operator errors in calculations. Other benefits are discussed within the paper. In the future, we hope to develop similar systems of data recording for QC checks on other radiotherapy equipment.     

Comparison of fMRI data from passive listening and active‐response story processing tasks in children

Purpose

To use functional MRI (fMRI) methods to visualize a network of auditory and language‐processing brain regions associated with processing an aurally‐presented story. We compare a passive listening (PL) story paradigm to an active‐response (AR) version including online performance monitoring and a sparse acquisition technique.

Materials and Methods

Twenty children (ages 11–13 years) completed PL and AR story processing tasks. The PL version presented alternating 30‐second blocks of stories and tones; the AR version presented story segments, comprehension questions, and 5‐second tone sequences, with fMRI acquisitions between stimuli. fMRI data was analyzed using a general linear model approach and paired t‐test identifying significant group activation.

Results

Both tasks showed activation in the primary auditory cortex, superior temporal gyrus bilaterally, and left inferior frontal gyrus (IFG). The AR task demonstrated more extensive activation, including the dorsolateral prefrontal cortex and anterior/posterior cingulate cortex. Comparison of effect size in each paradigm showed a larger effect for the AR paradigm in a left inferior frontal region‐of‐interest (ROI).

Conclusion

Activation patterns for story processing in children are similar in PL and AR tasks. Increases in extent and magnitude of activation in the AR task are likely associated with memory and attention resources engaged across acquisition intervals. J. Magn. Reson. Imaging 2009;29:971–976. © 2009 Wiley‐Liss, Inc.