Histological changes following surgically-assisted rapid tooth movement through resistance reduction and distraction osteogenesis in dogs

Objective To investigate the histological changes of rapid tooth movement in dogs treated by resistance reduction and distraction osteogenesis, aiming to establish an animal model and further to reveal the remodeling mechanism of rapid tooth movement. Methods A total of 8 local hybrid dogs were selected as subjects for this study. The second pre-molar was extracted on both sides. The experimental side underwent alvelor surgery for resistance reduction and a home-made tooth-borne intraoral distraction device was installed for rapid tooth movement, while for the other side (control side) only tooth-borne intraoral distraction device was used for rapid tooth movement. The longest active force-delivery span was 2 weeks, followed by 6-week retention. The distance between the moved tooth and anchor unit was recorded weekly, and radiography was performed for each side before and after distraction. The surrounding tissues including periodontal ligament and alveolar bone were sectioned for histological analysis. Results The average distance of tooth movement was 3.55mm on the experimental side and 1.11mm on the control side. The rate of tooth movement was notably higher (P<0.01) and no significant apical root resorption was detected by X-ray on the experimental side. The active alvelor bone remodeling was found on the tension and pressure sides. However, there was no significant difference between the experimental side and the control side after the retention period. Conclusion The rate of orthodontic tooth movement can be accelerated through resistance reduction and periodontal distraction without any unfavorable effects but at minimal anchorage loss.     

Correlation of expression of ER, PR and c-erbB-2 with ultrasonographic features in invasive ductal cancer of breast

Objective To analyze the relationship of the expression level of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2, c-erbB-2) of breast invasive ductal carcinoma (IDC) with ultrasonographic characteristics. Methods Totally 104 patients with IDCs confirmed pathologically were involved in this study. ER, PR and c-erbB-2 expression in the IDC specimens was determined by immunohistochemical staining technique. The correlation between the ultrasonographic features and the positive expression of ER, PR or c-erbB-2 was analyzed. Results The positive expression rate of ER and PR in the group with tumor spiculation sign and posterior acoustic attenuation was higher than that in the group without. The positive expression rate of ER differed significantly (P<0.05) while that of PR did not (P>0.05). The over-expression rate of c-erbB-2 in the group of microcalcification, sufficient blood flow and axillary lymph node metastasis was higher than that in the group of non-microcalcification, deficient blood flow or without axillary lymph node metastasis (P<0.05). The expression of ER, PR and c-erbB-2 was not related to the size of tumor (P>0.05). Conclusion The expression of ER and c-erbB-2 is closely related to the ultrasonographic characteristics of IDC, which may, to some extent, reflect the expression level of ER and c-erbB-2.     

子宫内膜基质干细胞的体外成骨诱导和成脂诱导分化

目的探讨子宫内膜基质干细胞的多向分化潜能。方法取因子宫肌瘤行全子宫切除术患者的子宫内膜组织,磁珠分选子宫内膜基质干细胞,进行传代培养。传代细胞分别加入成骨诱导剂和成脂诱导剂培养,并通过茜素红和油红O染色对成骨细胞和脂肪细胞形态进行鉴定。结果子宫内膜基质干细胞呈成纤维细胞样贴壁生长,其经成骨、成脂诱导培养3周后形态、体积发生明显改变。茜素红染色显示细胞团中央能形成钙化结节;成脂诱导后油红O染色可见细胞质内出现橙红色脂滴。结论子宫内膜基质干细胞经体外诱导培养后可向成骨细胞和脂肪细胞分化,并具有明显的成骨和成脂细胞形态,表明子宫内膜基质干细胞具有多向分化潜能。     

PDGFR信号通路促进星形胶质细胞和成纤维细胞共培养时细胞簇的成团效应

目的探讨血小板衍生生长因子受体(PDGFR)信号通路对小鼠脑星形胶质细胞和成纤维细胞共培养体系增殖的影响。方法取出生1～3 d的小鼠乳鼠大脑皮质培养星形胶质细胞,取脑膜培养成纤维细胞,免疫细胞化学荧光染色胶质纤维酸性蛋白(GFAP)鉴定星形胶质细胞纯度,染色纤连蛋白(FN)鉴定成纤维细胞纯度。通过向小鼠脑星形胶质细胞和成纤维细胞共培养细胞体系中加入细胞因子血小板衍生生长因子-BB(PDGF-BB)刺激细胞或抑制剂AG1296进行干预,观察各组细胞增殖情况,Western blot检测共培养细胞系中p-PDGFR-β、磷酸化的蛋白激酶B(p-Akt)的表达变化。结果鉴定结果显示星形胶质细胞和成纤维细胞的细胞纯度达到90%。显微镜下观察显示,加入PDGF-BB后星形胶质细胞和成纤维细胞共培养体系增殖明显并形成团块,给予抑制剂AG1296则增殖受到抑制,团块明显减少。Western blot结果显示加入PDGF-BB时,p-PDGFRβ、p-Akt表达增多(P<0.01);给予抑制剂AG1296则表达减少(P<0.05)。结论 PDGFR信号通路促进体外小鼠脑星形胶质细胞和成纤维细胞的增殖。     

从《骨》中的三对父女关系看华裔美国人的文化身份认同

摘要华裔美国人的文化身份认同问题,是华裔美国文学作家作品中常见的主题。伍慧明的《骨》是华裔美国文学作家作品中的代表作。它主要从安娜与父亲、尼娜与父亲、莱拉与父亲这三对父女之间的关系来集中展现华裔美国人的文化身份认同问题。三个女儿中,安娜是极端的反抗者,属于“失根”族群中的一员;尼娜是洒脱的西化者,她最终选择了抛弃中国文化身份;莱拉是温和的叛逆者,属于“落地生根”类型。文章认为,莱拉所展现的这种“落地生根”类型的混杂新文化身份,对于当代华裔文化身份认同有很强的借鉴意义。     

关于骨干校建设对推进高职内涵发展的思考

文中对国家骨干高职院校建设在推进高职内涵发展方面存在的问题进行了梳理,如中观层面指导与监管的不健全、建设环境不够完善、建设院校自身存在的问题等。在此基础上,提出以骨干校为契机建设高职院校内涵建设的若干策略,包括加强顶层设计,处理继承与创新的关系、重点与非重点的关系,解决好人才队伍问题、树立强大的文化自信等。     

高表达FGFR4细胞株的建立及其生物活性分析

目的构建FGFR4高表达细胞,研究FGFR4对细胞增殖能力的影响及相关蛋白活化机制,为研究以FGFR4为靶点的药物提供细胞模型。方法构建FGFR4真核表达载体并转染HEK293细胞,筛选稳定表达FGFR4细胞株,免疫印迹和免疫荧光分析FGFR4表达水平,细胞计数检测FGFR4高表达细胞的增殖情况,流式细胞仪检测FGFR4对细胞周期的影响,同时对ERK1/2磷酸化水平进行免疫印迹分析。结果在相同培养环境下,HEK293-FGFR4细胞同HEK293-pcDNA细胞相比,其增殖能力提高。周期分析表明,FGFR4使G0/G1期降低,促进细胞的增殖。同时,对MAPK信号通路进行了初步分析,发现FGFR4蛋白可以引起ERK1/2的磷酸化,从而导致MAPK/ERK1/2通路的激活,说明FGFR4可激活MAPK信号通路。结论成功构建了FGFR4高表达细胞株,为筛选以FGFR4为靶标的抗肿瘤药物奠定了前期实验基础。     

VEGF在食管腺癌中的表达及其与临床预后的关系

目的检测血管内皮生长因子(VEGF)在食管腺癌(esophageal adenocarcinoma,EAC)中的表达情况,并分析其与EAC患者临床病理学特征及预后的关系。方法运用免疫组织化学方法检测VEGF在126例EAC组织中的表达情况,结合EAC患者10年随访资料,分析VEGF的表达水平与EAC患者临床病理学特征及预后的关系。结果免疫组织化学结果显示,VEGF在食管腺癌细胞胞质中表达。126例EAC标本中,58例(46.0%)低表达,68例(54.0%)高表达。VEGF的表达水平与食管腺癌的T分期(P=0.017,χ2=9.462)和淋巴结转移情况(P=0.019,χ2=23.058)呈正相关,与分化程度呈负相关(P=0.006,χ2=9.075)。VEGF低表达组食管腺癌患者的中位总生存明显优于高表达组患者(P=0.035,χ2=6.632)。结论 EAC组织中存在VEGF表达且其表达水平与肿瘤的浸润深度、淋巴结转移、分化水平及患者预后相关,提示其可作为EAC治疗的新靶点。     

三氧化二砷对人胃癌裸鼠移植瘤血管生成素-2和血管内皮生长因子表达的影响

目的 研究三氧化二砷(As2O3)对肿瘤血管生成素-2(Ang-2)和血管内皮生长因子(VEGF)表达的影响.方法 用人胃腺癌细胞株SGC7901接种30只裸鼠皮下,建立实体瘤模型;然后随机分为As2O3高剂量(5mg/kg)、低剂量(2.5mg/kg)治疗组和对照组,每组各10只.治疗组接受As2O3腹腔注射10d,对照组注射生理盐水.测量肿瘤体积并计算抑瘤率;免疫荧光标记CD31并计算血管密度;免疫组化方法测定Ang-2的表达;免疫荧光激光共聚焦检测VEGF的表达.结果 砷剂治疗可抑制瘤块生长,2.5mg/kg和5mg/kg As2O3治疗组的抑瘤率分别为30.33%和50.85%.As2O3治疗组的微血管密度(MVD)、VEGF荧光表达水平均显著低于对照组(P＜0.01).Ang-2主要在血管内皮细胞的胞浆中呈强阳性表达,可清晰标记肿瘤内的血管;对照组和As2O3治疗组血管内皮细胞Ang-2表达强度无明显差异.结论 As2O3对Ang-2表达无明显影响,在As2O3治疗抑制瘤细胞VEGF表达的情况下,Ang-2表达可促进血管的退化.Ang-2主要在新生的内皮细胞表达,故可能作为新生血管的标记物,成为肿瘤新生血管研究的新指标.     

实验性左侧精索静脉曲张对青春期大鼠附睾中VEGF、VEGFR2蛋白表达的影响

目的 研究血管内皮生长因子(VEGF)及其受体2(VEGFR2)在实验性左侧精索静脉曲张(ELV)大鼠附睾中的表达和定位,探讨VEGF、VEGFR2在精索静脉曲张(VC)致男性不育中的作用.方法 通过部分结扎左肾静脉建立大鼠ELV模型,于术后2周和4周取材,采用免疫组化法检测VEGF、VEGFR2在附睾中的表达变化.结果 ELV大鼠两侧附睾中VEGF蛋白表达均上调,但ELV 4周组表达明显少于2周组;ELV 2周组大鼠附睾中VEGFR2蛋白的表达比对照组有所增加,而ELV4周组相比对照组和ELV 2周组均显著下降.结论 ELV对VEGF、VEGFR2蛋白的表达有影响,说明VC所致男性不育可能与VEGF及VEGFR2的表达变化有关.