Differential expression and localization of the phosphorylated and nonphosphorylated neurofilaments during the early postnatal development of rat hippocampus

Neurofilament (NF) proteins are expressed in most mature neurons in the central nervous system. Although they play a crucial role in neuronal growth, organization, shape, and plasticity, their expression pattern and cellular distribution in the developing hippocampus remain unknown. In the present study, we have used Western blotting and immunocytochemistry to study the low- (NF-L), medium- (NF-M), and high- (NF-H) molecular-weight NF proteins; phosphorylated epitopes of NF-M and NF-H; and a nonphosphorylated epitope of NF-H in the early postnatal (through P1-P21) development of the rat hippocampus. During the first postnatal week, NF-M was the most abundantly expressed NF, followed by NF-L, whereas the expression of NF-H was very low. Through P7-P14, the expression of NF-H increased dramatically and later began to plateau, as also occurred in the expression of NF-M and NF-L. At P1, no NF-M immunopositive cell bodies were detected, but cell processes in the CA1-CA3 fields were faintly immunopositive for NF-M and for the phosphorylated epitopes of NF-M and NF-H. At P7, CA3 pyramidal neurons were strongly immunopositive for NF-L and NF-H, but not for NF-M. The axons of granule cells, the mossy fibers (MFs), were NF-L and NF-M positive through P7-P21 but were NF-H immunonegative at all ages. Although they stained strongly for the phosphorylated NF-M and NF-H at P7, the staining intensity sharply decreased at P14 and remained so at P21. The cell bodies of CA1 pyramidal neurons and granule cells remained immunonegative against all five antibodies in all age groups. Our results show a different time course in the expression and differential cell type and cellular localization of the NF proteins in the developing hippocampus. These developmental changes could be of importance in determining the reactivity of hippocampal neurons in pathological conditions in the immature hippocampus.     

Role of behavioural disturbance in the loss of autonomy for activities of daily living in Alzheimer patients

BACKGROUND: Cognitive impairment is associated with functional impairment in patients with Alzheimer's disease (AD). Behavioural disturbance is very common in these patients. Nevertheless, there has been very little research into the relations between behavioural disturbance and functional status in AD. The purpose of this study is to investigate the relationship between behavioural disturbance and functional status after taking account of cognitive impairment. MATERIAL AND METHODS: 579 patients were prospectively evaluated at 16 French hospitals, all referents for AD, and were diagnosed with possible or probable AD. These patients were assessed with NeuroPsychiatric Inventory (NPI), cognitive subscales of the Alzheimer's Disease Assessment Scale (ADAS-cog), Clinical Dementia Rating scale (CDR) and Instrumental Activities of Daily Living scale (IADL). RESULTS: The number of men with available data for IADL total score was too small to make any analysis. 'Group A' gathered 256 women for whom the relation between autonomy for Activities of Daily Living (ADL) and the other variables were determined. 'Group B', pooled 85 women for whom relations found were verified. Linear regression was used for the analysis. With age, cognitive impairment allows us to explain best (38%) the loss of autonomy for ADL. CONCLUSION: The role of behavioural disturbances in the loss of autonomy for ADL was not determinant in our study, whereas cognitive impairment and age were better able to determine the loss of autonomy for ADL. Further study is needed to explain the decline of functional status in AD patients.     

An antibody that facilitates hematopoietic engraftment recognizes CD44

Pretreatment of recipients with the monoclonal antibody (MoAb) S5 facilitates engraftment of bone marrow from mismatched, unrelated donors in the canine transplantation model. In the direct comparisons reported here, the S5 glycoprotein (gp) was found to have structural homology to CD44 that in humans has been implicated in adhesive interactions of one type of effector cell, the lymphocyte. The S5 antigen and gp90Hermes-1 exhibited codistribution on canine peripheral blood cells. Both S5 and Hermes-1 (anti-CD44) MoAbs recognized 90-Kd species in radioimmune precipitations of 125I surface-labeled canine peripheral blood lymphocytes and bone marrow cells. Competitive antibody binding experiments showed that the epitope detected by S5 was distinct from that bound by Hermes-1 but overlapped with those defined by two other known anti-CD44 reagents, IM7 and Hutch-1. Sequential immunoprecipitation with S5 and Hermes-1 indicated that the two antibodies recognize the same or overlapping subsets of membrane gps. Tryptic digestion of S5 and anti-CD44 immunoprecipitates generated two major iodinated peptides of 27 and 35 Kd in both cases, a further indication of structural homology. Similarly, after N-glycanase digestion, S5 and CD44 immunoprecipitates were resolved to a single 68- Kd species. These findings suggest that CD44-mediated adhesive events may affect the fate of transplanted hematopoietic cells. The previous implications of this gp in T-lymphocyte activation and lymphocyte adhesion to endothelium thus provide useful paradigms to analyze its function in the bone marrow transplant setting.     

Ultraviolet irradiation of blood prevents transfusion-induced sensitization and marrow graft rejection in dogs

In a canine model using DLA-identical littermate pairs, we have shown that a regimen of three transfusions of donor blood given 24, 17, and 10 days before transplant uniformly leads to marrow graft rejection, presumably due to sensitization to minor (non-DLA) histocompatibility antigens. Untransfused dogs uniformly achieve sustained engraftment. In the present study, we investigated whether the exposure of blood to ultraviolet (UV) light (220-300 nm) prior to transfusion prevented sensitization of the recipient and allowed for successful marrow engraftment. Ten dogs were each given three pretransplant transfusions from the marrow donor. Each transfusion consisted of 50 mL of whole blood exposed in vitro to UV light for a total of 1.35 J/cm2. All ten dogs achieved engraftment. In contrast, all four dogs that had received sham-exposed transfusions rejected their grafts. In vitro studies revealed that although cell viability was not affected, leukocytes contained in UV-exposed blood were unable to function as stimulator cells in mixed leukocyte cultures or as accessory cells in mitogen- stimulated cultures. These data are consistent with the hypothesis that accessory cells are involved in transfusion-induced sensitization. We conclude that in vitro exposure of blood to UV light before transfusion prevents sensitization and allows for subsequent marrow engraftment.     

Childhood scoliosis: MR imaging

The spinal cords of 28 scoliosis patients between the ages of 1 month and 17 years were examined with magnetic resonance (MR) imaging. Complete visualization was obtained in all cases. In 15 patients (53%) neuropathologic abnormalities demonstrated by MR imaging significantly affected their clinical course, including tethered cords (n = 7), syringomyelia (n = 5), Arnold-Chiari I malformation (n = 4), spinal cord tumors (n = 2), Arnold-Chiari II malformation (n = 3), and diastematomyelia (n = 1). The advantages of MR imaging in the evaluation of the scoliotic spine in children include a high sensitivity for the occult conditions associated with scoliosis, good anatomic demonstration of the cord, and absence of bone artifacts. MR imaging is recommended as a primary imaging modality in scoliosis, following conventional radiography.     

胶原海绵复合新生大鼠原代心肌细胞构建工程化心肌组织

目的:探索以胶原海绵为支架、新生大鼠原代心肌细胞为种子细胞,于体外构建工程化心肌组织的方法。方法:实验于2005-12/2006-11在解放军第四军医大学西京医院心内科实验室完成。Ⅰ型胶原海绵剪切成方形片状(2.0cm×1.4cm×0.2cm),经60Co照射消毒,于DMEM培养液中水化1h左右。另取1d龄SD大鼠心脏,剪成小碎块,然后用2.5g/L胰蛋白酶于37℃中消化,吸取上清至含胎牛血清的DMEM中,重复消化四五次,用差速贴壁法除去大部分成纤维细胞,将细胞沉淀用DMEM培养液以2×109L-1的密度悬浮备用。将上述的心肌细胞悬液1mL缓慢滴注于玻璃模型中的胶原海绵上,然后置于细胞培养中培养。肉眼及显微镜主要观察工程化心肌组织在培养期间的自发收缩情况,包括收缩的部位、强度、频率、一致性以及收缩随时间变化的情况。苏木精-伊红染色观察工程化心肌组织内胶原纤维的变化,细胞形态,胞核的形状及细胞之间的连接。免疫组织化学染色和透射电镜观察工程化心肌组织片的形态和功能。结果:①细胞接种于胶原海绵上1d后,细胞/胶原复合物的凝胶化过程基本完毕,体积保持恒定,维持至培养结束,第3天细胞/胶原复合物局部出现点片状自发收缩,第5天整个细胞/胶原复合物出现同步化自发收缩,收缩频率61～199次/min。2周后37.5%的工程化心肌组织的自发收缩活动减弱,但75%的工程化心肌组织的自发收缩活动持续至培养结束。②苏木精-伊红染色、免疫组织化学染色和透射电子显微镜显示,工程化心肌组织内细胞间连接广泛存在,细胞多呈纵向分布,胞核呈长圆形,胞浆内α-肌节肌动蛋白阳性,胞内肌原纤维排列整齐,可见到心肌特异性的肌小节结构和Z线,多数细胞具有分化的心肌细胞表型。结论:用新生大鼠原代心肌细胞为种子细胞、以Ⅰ型胶原海绵为支架材料,构建出的工程化心肌组织,于体外可长时间持续自发收缩,该细胞/胶原复合物的形态结构与生理功能均类似于成熟大鼠心肌组织。     

胰岛移植过程中胰岛培养的研究现状

目的:总结胰岛移植过程中胰岛培养的研究现状,为利用胰岛培养准备更多更好的胰岛提供理论依据和技术支持。资料来源:以计算机检索Medline和Pubmed数据库1994-01/2007-01与胰岛培养相关的文章,检索词为“isle,tculture”,限定文章语言种类为English。同时计算机检索CNKI中国全文数据库1994-01/2007-01与胰岛培养相关的文章,检索词为“胰岛,培养”,限定文章语言种类为中文。资料选择:对资料进行初审,纳入标准:①与胰岛培养相关的文章。②1994年以后发表的文章。排除标准:Meta分析类文章。资料提炼:共检索到1384篇与胰岛培养相关的文章,入选33篇。对所检索文章的相关信息加以综合概括,其中关于胰岛培养中基础培养基、培养添加物、培养温度、密度等方面的文章18篇,关于胰岛培养新尝试的文章12篇。资料综合:将胰岛培养后再行移植有一定优势,包括降低免疫原性和为术前准备赢得时间等。目前对于挑选合适培养基及其添加物,调整合适培养温度、培养密度以及保护胰岛的活性等都有了比较深入细致的研究;同时很多学者开始尝试一些新的方法延长胰岛培养时间,改善胰岛功能,包括加入细胞外基质、与其他细胞共培养、选用微重力系统培养以及利用胶囊包裹培养等均显示良好的效果。结论:虽然胰岛培养可能会影响胰岛的活性和功能,但随着对胰岛生理和病理生理特性研究的深入,新的技术方法可将这些影响降到最低。胰岛培养给临床实践带来的便利是其最大的优势,加强胰岛培养的研究与应用有着重要的意义。     

Serum epidermal growth factor receptor and HER2 expression in primary and metastatic breast cancer patients

Background  

Breast tissue expression of the ERBB proto-oncogene family has been extensively studied. It was recently shown that expression of epidermal growth factor receptor (EGFR; c-erbB-1) and epidermal growth factor receptor (HER)2 (c-erbB-2) can be detected in the serum of breast cancer patients. The clinical relevance of this has not been fully established.     

Age-dependent cyclooxygenase-2 induction and neuronal damage after status epilepticus in the postnatal rat hippocampus

PURPOSE: Epileptic seizures lead to age-dependent neuronal damage in the developing brain, particularly in the hippocampus, but the mechanisms involved have remained poorly elucidated. In this study, we investigated the contribution of apoptosis and inflammatory processes to neuronal damage after status epilepticus (SE) in postnatal rats. METHODS: SE was induced by an intraperitoneal injection of kainic acid (KA) in 21- and 9-day-old (P21 and P9) rats. The expression of Bax, Bcl-2 and caspase-3, markers for apoptosis, and cyclooxygenase-2 (COX-2), an indicator for activation of inflammatory processes, were studied from 6 h up to 1 week after SE by Western blotting and immunocytochemistry. Neuronal damage was verified by Fluoro-Jade B staining. RESULTS: In P21 rats, SE resulted in neuronal damage in the CA1 neurons of the hippocampus. COX-2 expression was extensively, but transiently, increased and its immunoreactivity pronouncedly enhanced in several hippocampal subregions, amygdala, and piriform cortex by 24 h after SE. The expression of Bax and caspase-3 remained unchanged, whereas the antiapoptotic factor Bcl-2 transiently decreased by 24 h. Single caspase-3 positive neurons appeared in the CA1 region of both control and KA-treated rats. In P9 rats, no neuronal death was detected, and COX-2 expression and immunoreactivity remained at the control level. DISCUSSION: Our results suggest that SE provokes age-specific effects on COX-2 expression. This together with the activation of putative inflammatory processes may contribute to neuronal cell death in the hippocampus of postnatal rats, whereas caspase-dependent apoptosis seems not to be involved in the death process.