大鼠松果体细胞增龄变化

目的:探讨大鼠松果体细胞增龄变化。方法:SD大鼠,随机分为1～2月龄组,4～5月龄组,11～12月龄组和≥24月龄组4个组。采用H-F染色、Benda胶质细胞染色和TUNEL法细胞凋亡染色光镜观察,超薄切片透射电镜观察。结果:松果体细胞数从4～5月龄组至≥24月龄组递减(P<0.001),而胶质细胞数随增龄递增(P<0.01),松果体细胞凋亡随增龄增多(P<0.01),松果体细胞胞质随增龄电子密度降低,细胞器减少,线粒体扩张、嵴断裂呈空泡状,粗面内质网排列紊乱、池扩张,脂滴增多。结论:大鼠松果体随增龄而出现松果体细胞减少、胶质细胞增多,松果体细胞退变。这些变化可能是导致机体衰老的原因之一。     

基因组序列CGR图形表示的多重分形分析

为了更好地描述基因组序列CGR(chaos-game representation)图形的分形特征,引入多重分形理论进行分析。通过研究3种概率集对标度不变性范围的影响,选取出标度不变性最好的概率集,计算光滑的广义维数谱和多重分形谱。结果表明:以相对概率组成概率集时标度不变性最好,而且标度不变性随尺度变化可被分为3个不同的区域,这反映了基因组序列不同长度的序列片段有不同的分布规律。可见,多重分形方法可以用于描述基因组序列CGR图形的分形特征。     

全反式维甲酸对人乳腺癌MCF-7细胞凋亡的影响

目的:探讨全反式维甲酸(ATRA)对人乳腺癌MCF-7细胞凋亡的影响及作用途径.方法:在人乳腺癌细胞株MCF-7培养基中加入一定浓度ATRA和PKC-δ的专一抑制剂rottlerin(RO)并分组,通过SubG1assay by FACS、琼脂糖凝胶电泳检测基因组DNA ladder来观察ATRA对MCF-7的影响.结果:在浓度为5μM的ATRA作用下,MCF-7的凋亡率显著高于其它各组(P＜0.01),并可观察到明显梯状DNA.结论:ATRA能够诱导乳腺癌MCF-7细胞凋亡,但受PKC-δ的专一抑制剂RO的抑制.     

大学生主观幸福感及其影响因素

目的 考察大学生主观幸福感的现状,探讨自尊、社会支持、生活事件等对其主观幸福感的影响.方法 对1～4年级的300名大学生进行幸福感指数量表、自尊量表、社会支持评定量表和青少年生活事件量表等问卷测量.结果 ①大学生主观幸福感处于中等偏上水平(=9.71).②大学生主观幸福感得分在性别上存在显著差异(总分:t=2.239,P＜0.05).③大学生主观幸福感与自尊、社会支持呈显著正相关.④大学生主观幸福感与生活事件呈显著负相关.⑤自尊对大学生主观幸福感有显著的正向预测作用(β=0.308,P＜0.05).⑥社会支持对大学生的主观幸福感也有显著的正向预测作用(β=0.163,P＜0.01).结论 自尊和社会支持对大学生的主观幸福感有显著的正向预测作用,生活事件对大学生主观幸福感的影响较小.     

Changes in VP3 and VP5 genes during the attenuation of the very virulent infectious bursal disease virus strain Gx isolated in China

A very virulent infectious bursal disease virus (vvIBDV) Gx strain with high pathogenicity was attenuated through replication in specific-pathogen free (SPF) chicken embryos and in chicken embryo fibroblast (CEF) cell cultures. The changes in nucleotide sequences and the deduced amino acid sequences of VP3 and VP5 genes during attenuation were obtained. Sequence analysis of selected passages from numbers 0 to 20 in CEF’s (designated here Gx to CEF-20) showed that there were no amino acid changes detected in the VP3 and VP5 genes before CEF-9. There were some changes in the nucleotide sequence and amino acid substitutions in the VP3 and VP5 genes at CEF-9. CEF-9 was an intermediate with some amino acid changes which were possibly related to virulence. The amino acid sequences of VP2 and VP5 genes remained unchanged from CEF-10 to CEF-20. The results of pathogenicity test showed that the mortalities of vvIBDV-Gx, CEF-5, CEF-8, and CEF-9 were 64, 60, 60, and 28%, respectively, while there were no mortalities observed for CEF-10, CEF-15 and CEF-20. There was also no bursal atrophy when chickens were inoculated with CEF-10, CEF-15, and CEF-20. Virus neutralization tests with the Gx strain and sera from inoculated chickens showed that the antigenicity was similar from Gx to CEF-20. The implications of these findings for the study of IBDV virulence and a more effective control of vvIBDV are discussed.     

Mapping of epitopes of VP2 protein of chicken anemia virus using monoclonal antibodies

To map the epitopes of VP2 protein of chicken anemia virus (CAV), VP2 was expressed as a fusion protein in Escherichia coli BL21 (DE3). The Western blot demonstrated that recombinant VP2 protein could be recognized by sera of chickens infected with CAV. Female BALB/c mice were immunized with purified recombinant VP2 produced in E. coli BL21 (DE3) and seven VP2-specific monoclonal antibodies (MAbs) were developed. The results of Western blot showed that all the seven MAbs recognized the recombinant VP2 protein expressed in the baculovirus and reacted with MDCC-MSB1 cells infected with CAV by indirect immunofluorescence assay. The VP2 protein was dissected into 21 overlapping fragments, expressed as fusion peptides in E. coli and used for epitope mapping by pepscan analysis. ELISA and Western blot assays indicated that most of MAbs reacted with the 12th and 13th fragments (amino acids 111-136) and one of them reacted with the 3rd fragment (amino acids 21-36). The linear immunodominant epitope of VP2 was located mainly in amino acid residues 111-126 and 121-136.     

AF椎弓根螺钉内固定系统治疗胸腰椎爆裂性骨折：30个月随访的中远期效果分析

背景：研究证实后路短节段椎弓根螺钉系统治疗无神经症状的胸腰椎爆裂性骨折,能够提供足够的稳定性,有效恢复椎体高度、生理弧度和椎管容积。 目的：评价AF椎弓根螺钉内固定系统治疗胸腰椎骨折的效果。 方法：分析51例应用AF经椎弓根内固定系统治疗胸腰椎爆裂性骨折患者内固定治疗的中远期疗效。利用X射线片检查内固定前后、拆除内固定前、拆除内固定后随访时的椎体前后缘高度和计算Cobb’s角,CT观察椎管占位情况,利用Frankel分级评估神经功能恢复情况,Christian评分评价功能情况,Denis分级评估疼痛程度。 结果与结论：患者均随访30个月以上。与内固定前比较,内固定后、拆除内植物及末次随访时Cobb’s角及椎体前、后缘高度明显增加(P < 0.01),CT观察椎管占位明显恢复。内固定前存在脊髓不完全损伤24例,内固定后完全恢复22例。功能活动Christian评分：3分1例,4分3例,5分15例,6分20例,7分12例。腰痛程度按Denis评估,无痛42例,偶有微痛9例。满意度患者自我评测：非常满意35例,满意16例。内固定钉断裂1例1枚。表明AF椎弓根内固定系统能达到满意复位、牢固固定、有效椎管减压的目的,能有效治疗胸腰椎骨折。 关键词：胸椎;腰椎;骨折;AF椎弓根系统;治疗结果 doi:10.3969/j.issn.1673-8225.2012.13.023     

选择性深低温血流阻断猴海马超微结构和波形蛋白表达的变化**

背景：前期研究显示,选择性深低温顺行脑灌注能提高猴脑对缺血缺氧的耐受性。 目的：观察选择性深低温血流阻断对猴海马超微结构和波形蛋白表达的影响。 方法：将8只健康成年恒河猴随机分为两组：深低温组(n=5)在常温下阻断猴双侧颈总动脉及颈内静脉10 min,然后通过一侧颈内动脉灌注4 ℃林格氏液,同侧颈内静脉回流,使脑温维持在18 ℃以下,60 min后恢复脑血流;常温组(n=3)除灌注液改为37 ℃林格氏液外,其余与深低温组相同。 结果与结论：深低温组猴全部成功复苏,海马组织形态及超微结构未见明显异常。常温组猴全部死亡,未能成功复苏,海马组织形态及超微结构有不同程度异常。与常温组比较,深低温组海马波形蛋白表达显著降低(P < 0.01)。说明阻断双侧颈总动脉10 min后行选择性深低温顺行脑灌注可下调海马波形蛋白表达,保护海马组织,减轻脑缺血损害。     

骨髓基质细胞促进永久性局灶性脑缺血大鼠脑室下区的神经发生

目的 探讨移植骨髓基质细胞(BMSCs)对永久性局灶性脑缺血大鼠脑室下区(SVZ)细胞增殖的影响及其增殖细胞类型分析. 方法制作永久性局灶性脑缺血大鼠模型,分为空白对照组(MCAO)、PBS对照组(MCAO PBS)和治疗组(MCAO BMSCs),每组动物再分为脑缺血后7d和14d亚组.空白对照组不予处理,PBS对照组在脑缺血后1d移植PBS,治疗组在脑缺血后1d移植BMSCs.用Zausinger六分法检测神经功能恢复情况;注射5-溴脱氧鸟嘧啶核苷(BrdU)标记SVZ的新增殖细胞,免疫荧光双重标记检测新增殖细胞的类型. 结果在脑缺血后7d和14d,与两个对照组相比,治疗组的神经功能评分较高,有显著性差异(P<0.05);脑缺血后14d,治疗组的大鼠患侧SVZ的BrdU阳性细胞较其余两组高,存在显著差异(P<0.05);免疫荧光双重标记显示,新增殖细胞表达神经元和星形胶质细胞的标志物,提示新增殖细胞为神经元和神经胶质细胞的混合体. 结论 BMSCs可以改善永久性局灶性脑缺血大鼠的神经功能,其机制可能与促进SVZ的神经细胞增殖有关.     

Breast carcinoma with micropapillary features: clinicopathologic study and long-term follow-up of 100 cases

To study the clinicopathologic characteristics and prognosis of invasive micropapillary carcinoma of breast (IMPC), 100 cases of invasive breast carcinoma with an IMPC component were reviewed. Compared with invasive ductal carcinoma, not otherwise specified, with similar histologic grades, carcinomas with IMPC were larger sized, had a higher lymph node metastasis rate with more nodes involved per case, and exhibited increased lymphovascular invasion. The presence of IMPC strongly correlated with the more aggressive behavior. No significant association was established between the proportion of the IMPC component and overall tumor size, histologic grade, lymph node metastasis rate, and distant metastasis, but a trend was noted. Long-term follow-up demonstrated a poorer 5-year and 10-year survival rate for patients with breast carcinoma containing an IMPC component. Breast carcinomas with micropapillary features are more aggressive tumors with a poorer prognosis. This specific structure should be carefully evaluated in the surgical pathology examination of breast carcinoma specimens.