1.Fabrication of molecular probe targeting NRP-1 and magnetic resonance molecular imaging of gliomas in vitro
Yuheng SHAN ; Zhikong LIANG ; Yanchen LIN ; Lili DAI ; Yuliang WANG ; Yanhua GONG
Chinese Journal of Behavioral Medicine and Brain Science 2016;25(8):677-681
Objective To synthetize a novel MR molecular imaging probe named USPIO?PEG?tLyP?1,and to evaluate its value in detecting U87 cells by MR imaging. Methods USPIO?PEG?tLyP?1 was synthetized by conjugating USPIO?PEG with tLyP?1. Neuropilin?1 expression levels of glioma cell lines were detected by Western blot. The cytotoxicity of USPIO?PEG and USPIO?PEG?tLyP?1 were assessed by MTT colorimetric assay. The uptake efficiency of USPIO?PEG?tLyP?1 was measured by Prussian blue staining, transmission electron microscope and MR imaging in vitro. Results The novel MR molecular imaging probe was synthetized with an average diameter of 43.84 nm. U87 glioma cell line was screened as test subject for the highly expression of NRP?1(P<0.05). USPIO?PEG?tLyP?1 group showed much more intracellular blue particles than USPIO?PEG group after Prussian blue staining. After incubation,USPIO?PEG?tLyP?1 mainly existed in lysosme,endoplasmic reticulum and mitochondria. In vitro MRI showed that USPIO?PEG?tLyP?1 significantly enhanced the negative contrast effect compared with USPIO?PEG(P<0.01). Conclusion The decoration of tLyP?1 enhanced targeting ability of USPIO?PEG to glioma cells and MR molecular imaging can be a promising method for early diagnosis of gliomas.
2.Ultrastructural characteristics of synapses consisted of M-enkephalin immunoreactive terminals in the marginal division of the monkey striatum
Bin WANG ; Jiaoyu MAO ; Lin MA ; Mengsha LU ; Sheng WU ; Yanchen CHEN ; Siyun SHU
Chinese Journal of Neuromedicine 2014;13(1):45-49
Objective Marginal division (MrD) of striatum is a universal structure in the mammalian brain,and it plays an critical role in learning and memory.In the present study,we try to investigate the synaptic ultrastructure of Methionine enkephalin (MET-ENK) immunoreacted fibers connected with neurons in the marginal division of the striatum in the monkey brains to explore the ultrastructural basis of the mechanism of learning and memory function in MrD.Methods Six male monkeys (macaque) were perfused with paraformaldehyde through heart to fix the brain and the brains were sectioned by a cryostat.Sections of the brains were performed immunohistochemical staining to detect the MET-ENK expression in the stfiatum; the areas with positive immumohistochemical staining was performed ultrastructural observation for morphological characteristics of the MET-ENK synapses in the MrD.Results Immunohistochemistry staining showed a dense arrangement of MET-ENK immunoreactive cells between the putamen and globus pallidus.Five major types of MET-ENK synapses were identified in the MrD:the axo-dendritic synapses,the axo-spinous synapses,the axo-somatic synapses,the axo-axonic synapses and the compound synapses.Conclusion The MET-ENK synapses in the MrD are diverse and complex,and can be distinguished from the rest of the striatum.
3.Development and evaluation of reliability and validity of new scales measuring severity of myasthenia gravis
Haifeng LI ; Lin WANG ; Xiang GAO ; Meng XIA ; Xu ZHANG ; Huan YANG ; Hongyu ZHOU ; Yanchen XIE ; Wei QIU
Chinese Journal of Neurology 2018;51(6):430-437
Objective To develop new scales on the severity of myasthenia gravis ( MG) which are suitable for clinical practice in China .Methods A final version of new comprehensive scale was developed by item optimization from a preliminary scale established by combination of Delphi method and previous evaluation of items from source scales .With the original quantitative data from 60 MG patients, items were selected on the basis of interobserver and test-retest reliability of items , the contributions of items on internal consistency and construct validity of the preliminary scale .Evaluation of this final scale includes internal consistency, interobserver and test-retest reliability, construct validity and correlation with currently used scales.A self-rating version was simplified from the final scale by including items that can be measured by patients, which was then evaluated in 57 generalized MG patients.Results One item ( palpebral fissure ) was deleted from the preliminary scale due to poor interobserver and test-retest reliability.The remaining nine items constituted the final comprehensive scale which covered six commonly involved muscle groups in MG.All items in the comprehensive scale had fair to excellent interobserver reliability ( K=0.43-0.80, P<0.01) and fair to excellent test-retest reliability ( K =0.41 -1.00, P<0.01) .The comprehensive scale had acceptable internal consistency (Cronbach ɑ=0.63), excellent interobserver reliability (intraclass correlation coefficient (ICC) =0.88, P<0.01) and test-retest reliability (ICC=0.86, P<0.01).The comprehensive scale had four common factors and good construct validity ( cumulative dedication rate 68.46%).There was high correlation between the comprehensive scale and Myasthenia Gravis Composite ( MGC ) , Absolute and Relative Score of MG ( ARS-MG ) and Quantitative Myasthenia Gravis score (QMGs) ( r=0.87 -0.90, P<0.01), and moderate correlation between the comprehensive scale and Myasthenia Gravis Activities of Daily Living (MG-ADL) (r=0.68, P<0.01).A self-rating scale was developed by deleting ocular and facial items and keeping the remaining six items , which covers the bulbar , limb, neck and respiratory muscles.Internal consistency (Cronbach ɑ=0.69), interobserver reliability and test-retest reliability (ICC=0.90 for both, P<0.01) of the self-rating scale were better than those of the comprehensive scale.The self-rating scale had two common factors and good construct validity ( cumulative dedication rate 64.24%) .There was high correlation between the self-rating scale and the comprehensive scale, MGC and ARS-MG (r=0.74-0.86, P<0.01), and moderate correlation between the self-rating scale and QMGs and MG-ADL ( r=0.55 -0.68, P<0.01 ) .Conclusions Item optimization was performed from a preliminary scale established by Delphi method .A new comprehensive scale and a self-rating scale were developed .The comprehensive scale and self-rating scale had good reliability and validity , which can be used to assess the severity of MG reliably and effectively .