Accelerated 3D echo-planar spectroscopic imaging at 4 Tesla using modified blipped phase-encoding.

Whole-brain echo-planar spectroscopic imaging (EPSI) often substantially lengthens MRI/MRSI (magnetic resonance spectroscopic imaging) protocols. To halve acquisition time, application of a blipped phase-encoding (PE) gradient during the EPSI readout (RO) was previously suggested by PE of the even RO echoes in k-space at an interstitial location along k(PE), separated from the odd RO echoes, effectively reducing the number of PEs by a factor of 2. However, the approach is very susceptible to phase inconsistencies between even and odd RO echoes in the presence of B(0) inhomogeneities and gradient imbalance, leading to ghosting in the PE direction. In this work, the blipped PE gradient is placed in between pairs of even/odd RO gradient lobes to avoid these problems. This approach is demonstrated in a phantom and in normal human brain in vivo at 4T. While the proposed method allows substantial reduction in metabolite ghosting, it may be limited by the presence of a relatively large spurious signal at the Nyquist frequency.     

Sequencing of the alpha-synuclein gene in a large series of cases of familial Parkinson's disease fails to reveal any further mutations. The European Consortium on Genetic Susceptibility in Parkinson's Disease (GSPD)

A mutation in exon 4 of the human alpha-synuclein gene was reported recently in four families with autosomal dominant Parkinson's disease (PD). In order to examine whether mutations in this exon or elsewhere in the gene are common in familial PD, all seven exons of the alpha- synuclein gene were amplified by PCR from index cases of 30 European and American Caucasian kindreds affected with autosomal dominant PD. Each product was sequenced directly and examined for mutations in the open reading frame. No mutations were found in any of the samples examined. We conclude that the A53T change described in the alpha- synuclein gene is a rare cause of PD or may even be a rare variant. Mutations in the regulatory or intronic regions of the gene were not excluded by this study.      

Regulation of stimulated integrin surface expression in human neutrophils by tyrosine phosphorylation

The control of the adhesive properties of human neutrophils is an essential element of their defense function. One level at which this control is exerted involves the upregulation of the surface expression of beta 2-integrins. In this study, we have examined the potential involvement of tyrosine phosphorylation in the latter process. Two inhibitors of tyrosine kinases with differing modes of action, erbstatin and herbimycin A, were found to inhibit the expression of CD11b and CD18 stimulated by chemotactic factors (fMet-Leu-Phe or leukotriene B4) or growth factors (tumor necrosis factor alpha). This inhibition was not shared by an inactive analog of erbstatin or by the protein kinase C inhibitor Ro 31-8330. Erbstatin also inhibited the unveiling of activation-specific neoepitopes detected by antibody CBRM1/5. Pretreatment of neutrophils (but not of endothelial cells) with erbstatin inhibited the stimulation of neutrophils' adherence to endothelial cells induced by fMet-Leu-Phe. Augmentation of tyrosine phosphorylation by inhibiting tyrosine phosphatases using hydroperoxyvanadate led to an increased surface expression of CD11b and CD18 and enhanced the adhesion of neutrophils to endothelial cells. Finally, the leumedin NPC 15669, which had previously been shown to inhibit stimulated CD11b expression and neutrophil adherence to endothelial cells and to exhibit anti-inflammatory properties in various in vivo models of inflammation, inhibited the stimulation of tyrosine, phosphorylation induced by fMet-Leu-Phe. Taken together, these data establish a strong correlation between tyrosine phosphorylation and integrin upregulation in stimulated human neutrophils.     

自体骨髓单个核细胞经介入途径移植治疗股骨头坏死54例：12个月疗效随访

目的:观察经介入途径移植自体骨髓单个核细胞在股骨头坏死治疗中的应用,并评价其疗效。方法:选择2004-07/2005-11在解放军四六三院细胞治疗中心住院的,具有完整随访资料的股骨头坏死确诊患者共54例91髋。纳入确诊股骨头坏死,有关节疼痛、功能障碍等症状患者,性别、年龄不限;排除有严重心力衰竭、严重肾功能异常等不能耐受手术者。符合纳入标准54例,男45例,女9例,12～68岁。按ARCO分期Ⅱ期42髋,Ⅲ期47髋,Ⅳ期2髋。实验对象对治疗的相关内容知情同意并签知情同意。干预措施:抽取患者髂后上嵴骨髓进行单个核细胞悬液的制备。在DSA监视下将采集的单个核细胞混悬液经股动脉行Seldinger法穿刺,穿刺成功后,置入4F动脉鞘,经动脉鞘置入Cobra导管,将导管超选择至闭孔动脉及旋股内外侧动脉,平均注入单个核细胞悬液。术后定期随访症状变化情况,1年后复查X射线或CT,随访疼痛、关节活动度等情况。实验评估:①疼痛指数:无疼痛症状为3分,Harris髋关节评分疼痛分级A级;时有隐痛2分,Harris髋关节评分疼痛B级;轻度疼痛为1分,Harris髋关节评分疼痛C级;中度疼痛为0分,Harris髋关节评分疼痛D级。②功能指数:髋关节屈、伸、展、收、旋转度评分达Harris髋关节活动范围评分4～5分为3分;3～4分为2分;2～3分为1分;小于2分为0分。③X射线平片指数:股骨头形态无变化,应力骨小梁清晰,坏死区明显缩小为3分;坏死区略缩小为2分;治疗前后无明显变化为1分;坏死区扩大为0分。④血管指数:治疗后旋股内、外侧动脉及其分支增粗、增多,延长1cm以上者3分;1～0.5cm者2分;小于0.5cm者1分,无变化者0分。结果:54例患者均完成疼痛症状、关节功能及影像学随访1年。①术后12个月复查疼痛消失9髋,缓解61髋,无缓解21髋,缓解率为76.9%。②关节功能缓解33髋,无缓解58髋,缓解率为36.3%。③1年后X射线平片或CT、MRI示股骨头区可见不同程度的股骨头坏死区骨质密度改变,坏死区有吸收、缩小,股骨头形态变圆滑规整,改善28髋,无缓解或加重63髋,缓解率为30.1%。④12例24髋完成术后12个月复查股骨头供血动脉数字减影血管造影,好转18髋,好转率为72.2%。结论:经介入途径移植自体骨髓单个核细胞治疗股骨头坏死损伤小,可缓解临床相关症状。     

Cinguloparietal atrophy distinguishes Alzheimer disease from semantic dementia

BACKGROUND: Progressive brain atrophy is associated with Alzheimer disease (AD) and other dementias. Regional differences in brain atrophy may reflect clinical features of disease. OBJECTIVE: To identify regions of cerebral atrophy that are associated with AD vs other dementias. SETTING: University hospital dementia clinic. PARTICIPANTS: Eleven patients with AD and 11 with semantic dementia (SD), matched for age, sex, education, and degree of overall cognitive impairment and 15 normal controls. METHODS: Voxel-based morphometry was used to compare patterns of gray matter loss, measured on T1-weighted magnetic resonance images, between patients with AD or SD, a subtype of frontotemporal lobar degeneration, and controls. Statistically significant differences in regional gray matter concentration, after multiple-comparisons correction, between groups of subjects were identified. RESULTS: Patients with AD were more impaired than those with SD on tests of visuospatial function and on simple calculations. Consistent with these neuropsychological deficits, the most significant area of atrophy in the AD group was the left parietal cortex vs controls (z = 5.0; P =.04). Compared with SD, AD was associated with more atrophy in the left parietal lobe (z = 5.6; P =.04) and bilaterally in the posterior cingulate/precuneus (z = 5.1; P =.04). A discriminant function analysis demonstrated that the degree of atrophy of right posterior cingulate, left parietal lobe, right amygdala, and right anterior temporal lobe structures correctly classified 96% of the patients. CONCLUSION: Alzheimer disease is associated with a specific pattern of cortical atrophy compared with SD.