短发卡RNA对人胃癌细胞STAT3基因的沉默作用

目的:探讨STAT3基因小发夹RNA（shRNA）表达质粒对胃癌MKN-45细胞STAT3基因的干扰作用。方法:根据STAT3 mRNA 编码序列，设计RNA干扰靶点，构建STAT3基因的特异性小RNA干扰质粒（psiRNA-H1/STAT3），使用脂质体转染人胃癌细胞系（MKN-45细胞）。实验分为对照（A）组，psiRNA-H1转染（B）组和psiRNA-H1/STAT3转染（C）组。通过RT-PCR和Western Blot检测STAT3特异性小RNA干扰基因对胃癌细胞STAT3基因mRNA和蛋白表达的影响。结果:psiRNA-H1/STAT3经限制性酶切及部分序列分析证明基因插入正确，并经测序证实。将其成功转染MKN-45细胞后，该细胞的STAT3 mRNA和蛋白表达均明显下降(P<0.05)。 结论:将成功构建的针对STAT3基因的shRNA表达载体转染MKN-45细胞，能有效抑制该细胞的STAT3 mRNA和蛋白表达，为STAT3基因靶向治疗提供一定的实验依据。     

RNA干扰沉默Cathepsin L基因表达对肝癌细胞生物学特性影响的实验研究

目的 探讨RNA干扰技术沉默Cathepsin L基因对肝癌细胞生物学特性的影响.方法 实验组为肝癌细胞CathepsinL siRNA转染基因沉默组(沉默组),实验对照为肝癌细胞空白对照组(空白组)和siRNA转染荧光蛋白对照组(荧光对照组).观察时间为Cathepsin L siRNA转染后1、3和6 d.观察各组肝癌细胞Cathepsin L siRNA转染效率.用免疫荧光、RT-PCR法及WB法检测肝癌细胞Cathepsin L表达,MTT法检测细胞活力,流式细胞仪检测细胞周期和凋亡变化,侵袭小室法测定肝癌细胞侵袭力变化.结果 沉默组与空白组、荧光对照组比较,Cathepsin L mRNA水平和蛋白水平显著下降,细胞生长受抑制,增殖指数显著下降,细胞凋亡率显著增加,肝癌细胞侵袭力显著下降.结论 RNAi可有效沉默肝癌细胞Cathepsin L表达,降低肝癌细胞增殖活力及细胞侵袭力.     

乳腺癌高表达基因1对前列腺癌细胞神经内分泌转化的影响

目的观察乳腺癌高表达基因1(BCOX1)在前列腺癌细胞神经内分泌转化中的表达水平和生物功能。方法构建去雄激素诱导的神经内分泌样前列腺癌细胞模型。并检测BCOX1在LNCaP和AI-NEPC细胞中的表达差异。RNA干扰技术下调BCOX1在AI-NEPC细胞中表达后,检测神经内分泌细胞标记物NSE和CHGA的表达,并检测STAT3的表达和磷酸化水平。结果在AI-NEPC中BCOX1蛋白表达水平与LNCaP细胞相比明显增加。BCOX1mRNA水平在AI-NEPC中与LNCaP细胞相比显著增高(P0.05)。shRNA转染组中NSE和CHGA表达水平与未转染组和空载体转染组比较均明显下降(P0.05)。shRNA转染组中STAT3和磷酸化STAT3的表达水平较空载体转染组明显下调(P0.05)。结论 BCOX1在神经内分泌分化的前列腺癌细胞中高表达,下调BCOX1的表达可以影响前列腺癌细胞的神经内分泌样表型,并抑制STAT3的表达和磷酸化。     

慢病毒RNA干扰GRP78对肾癌细胞生物学行为的影响研究

目的:探讨慢病毒RNA干扰GRP78蛋白后对肾癌细胞生物学行为的影响。方法:构建慢病毒靶向siRNA-GRP78干扰载体进入肾癌细胞株。转染48h后使用Realtime-PCR和Western bloting检测GRP78基因和蛋白表达,MTT法和transwell法分别检测肾癌细胞增殖和侵袭力。结果:转染48h后,Realtime-PCR和Western bloting检测证实siRNA1抑制GRP78基因和蛋白效率最佳。SiRNA1-GRP78可抑制肾癌细胞增殖和降低细胞侵袭力,促进细胞凋亡,阻滞细胞于G1期。结论:慢病毒RNA干扰可有效抑制肾癌细胞中GRP78基因和蛋白表达,GRP78表达下调影响肾癌细胞增殖和降低细胞侵袭力,诱导细胞凋亡,阻滞细胞于G1周期。GRP78可能成为肾癌治疗新靶点。     

赖氨酰氧化酶样蛋白-2对胰腺癌细胞的影响

目的 观察沉默赖氨酰氧化酶样蛋白-2(LOXL2)基因对胰腺癌细胞的影响.方法 利用脂质体法将构建好的LOXL2-短发卡RNA(shRNA)质粒转染到胰腺癌Panc-1细胞中,应用Western blot检测转染前后胰腺癌Panc-1细胞中LOXL2蛋白表达量的变化,Transwell侵袭实验检测胰腺癌细胞的体外侵袭力,MTT法检测胰腺癌细胞的黏附能力.结果 LOXL2-shRNA转染组Panc-1细胞中LOXL2蛋白表达水平(0.32±0.01)、体外侵袭力[(32.2±3.8)个]、黏附率[(75.4±3.2)％]较转染前[1.05±0.05、68.6±3.5、(90.3±2.1)％,P＜0.05]明显降低.结论 沉默LOXL2基因能抑制胰腺癌Panc-1细胞的侵袭能力和黏附能力.     

抑制信号转导与转录激活因子-3基因表达对人胰腺癌细胞转移能力的影响

目的 探讨RNA干扰(RNAi)技术抑制信号转导与转录激活因子-3(STAT3)表达对人胰腺癌细胞株SW1990体内转移能力的影响及其机制.方法 构建STAT3短发卡RNA(shRNA)表达载体,稳定转染SW1990细胞.应用RT-PCR方法 观察STAT3 mRNA表达的改变,EMSA方法 检测STAT3-DNA结合活性的改变.应用裸鼠急性血路转移实验检测细胞体内转移能力的变化,并通过RT-PCR方法 检测基质金属蛋白酶-2(MMP-2)和血管内皮生长因子(VEGF)mRNA表达的改变.结果 STAT3 shRNA表达载体稳定转染SW1990细胞可显著抑制STAT3 mRNA表达和STAT3-DNA结合活性(P＜0.05);裸鼠急性血路转移实验显示,RNAi技术抑制STAT3后,SW1990细胞体内转移能力明显下降(P＜0.05);RT-PCR结果 显示,RNAi技术抑制STAT3后,SW1990细胞中MMP-2和VEGF的mRNA表达明显减低(P＜0.05).结论 RNAi技术能有效抑制STAT3基因表达,并可通过下调MMP-2和VEGF表达抑制胰腺癌细胞体内转移能力.     

VTCN1基因沉默对膀胱癌HT-1376细胞增殖和转移的影响

目的 通过RNA干扰技术下调VTCN1基因在人膀胱癌HT-1376细胞株中的表达,观察VTCN1基因表达下调后对膀胱癌细胞生物学行为的影响.方法 将针对VTCN1基因的小干扰RNA(siRNA)序列重组入真核表达载体中构建pU-VTCN1-siRNA,转染至膀胱癌HT-1376细胞株中,采用逆转录-聚合酶链反应(RT-PCR)、Western blot法检测转染pU-VTCN1-siRNA后的HT-1376细胞中VTCN1在基因和蛋白表达.采用流式细胞仪分析转染pU-VTCN1-siRNA后的HT-1376细胞的细胞周期,应用Transwell侵袭小室模型观察转染pU-VTCN1-siRNA后HT-1376细胞侵袭力.结果 转染pU-VTCN1-siRNA后的HT-1376细胞中,VTCN1的基因和蛋白表达水平显著下降(P＜0.05),细胞周期被阻滞在G1期,G1期细胞从37.3％上升到74.6％,而S期细胞由46.36％下降到8.9％(P＜0.05),Transwell侵袭实验显示侵袭细胞数由空载组(278 ±42)个和空白组(293±460个下降为实验组的(39±6)个,体外侵袭能力明显下降(P＜0.05).结论 通过siRNA技术下调VTCN1基因表达能抑制HT-1376细胞增殖和侵袭能力.     

Hazards and complications of endoscopic transurethral ureterolithotripsy and lithoextraction and means of prevention

Complications related to ureterolithotomy and ultrasonic ureterolithotripsy performed under the control of visual endoscope were analyzed in 86 ureterolithiasis patients, methods of their prevention discussed. All the aforementioned complications were distributed into three groups: inapplicability of surgery due to anatomic and functional defects of lower and upper urinary tracts, intraoperative, and postoperative complications. The commonest ones were ureteral abruption and perforation, acute pyelonephritis, temporary vesicoureteral reflux. Their control measures were considered as relative methods of treatment: immediate surgical intervention in case of ureteral abruption, renal catheterization in patients with insignificant ureteral perforation or acute pyelonephritis. Adequate ureteroscopy, careful consideration of pro- and contraindications, catheterization of renal pelvis and urinary bladder performed within 2-3 days after the surgery and adequate antibacterial therapy are the most decisive steps in the control of aforementioned complications.     

牙体牙弓颌骨阻力中心及其临床意义

牙体、牙弓及颌骨的阻力中心在正畸矫治力系统中具有重要的意义,也是正畸学领域争论较多的一个问题。Dermaut等研究表明,当力作用于物体阻力中心时,物体将发生平动,否则将发生平动和转动的复合运动。目前,国内外多数学者认为牙体、牙弓及颌骨存在阻力中心,但其位置存在争议。本文就牙体、牙弓及颌骨的阻力中心及其临床意义作一综述。     

Characterisation and differentiation of chondroblastomas and chondromyxoidfibromas - presence and expression of collagen types I and II

AIM: Chondroblastomas and chondromyxoidfiibromas are rare benign skeletal neoplasms with reported overlapping histology. Aim of this study was to analyse the biochemical composition of the matrix of these tumour entities in order to further characterise the cellular phenotypes of these neoplasms using typical cell biological marker genes. METHODS: The matrix compositions of chondroblastomas and chondromyxoidfibromas were analyzed by HE-histology, histochemistry, and immunolocalization techniques. Cellular gene expression patterns were detected by mRNA in situ hybridization. RESULTS: Chondroblastomas are rich in collagen type I and show foci of an osteoid-like matrix, whereas collagen type II as a typical marker of chondrocytic differentiation was not detected in any of the specimens. Chondromyxoidfiibromas had foci of chondroid appearance with chondroblastic cellular differentiation characterised by collagen type II expression. CONCLUSION: These results characterise chondroblastomas and chondromyxoidfiibromas as skeletal neoplasms that have a different biology and which can be distinguished by matrix protein expression products: collagen type II, the typical marker of chondroblast differentiation, could only be detected in chondromyxoidfibromas, but not in chondroblastomas. Thus, both neoplasms are clearly different on the cell biological level.     

Histochemical and contractile properties of striated muscles of urethra and levator ani of dogs and sheep

AIMS: To understand their possible importance in long- and short-term control of continence, some properties of the striated muscles of the urethra and pelvic floor (levator ani) of dogs and sheep were investigated, especially fiber types and contractile characteristics. MATERIALS AND METHODS: Striated muscles of urethra and levator ani of 29 male and 6 female dogs and 11 male and 6 female sheep were removed and cut into strips. Some strips were frozen and stained for ATPase at pH 9.4 and 4.3 for fiber typing; others were set up in an organ bath to study contractile responses to nerve stimulation. RESULTS: All muscles contained both type I (slow) and type II fibers, ranging from 97% type II in female greyhound urethra to 60% in female sheep levator ani. For each muscle, there were fewer type II muscles in sheep than in dog. The diameters of the urethral fibers were about 60% of the levator ani in dogs and 34% in sheep. Contraction of the urethral muscle was faster than for levator ani and declined to about 80% of the peak, 500 msec after the beginning of stimulation at 20 Hz. The levator ani contraction rose to a steady level as long as stimulation continued. CONCLUSIONS: Both the levator ani and urethral striated muscles contain slow and fast fiber types. The levator ani muscles are capable of sustained contraction with rapid onset which will produce long-term closure of the urethra. The circular urethral muscle contraction was faster but less well maintained.     

Incorporation and release of85Sr and14C-proline-hydroxyproline in mineral and collagen of bone and incisor teeth of growing rats

The extent to which exchange and reutilization processes of mineral tracers affect skeletal mineral accretion and resorption measurements was evaluated by comparing the rates of appearance and disappearance of⁸⁵Sr and¹⁴C-proline-hydroxyproline in bones and teeth in growing rats for 12 days following simultaneous parenteral injection of these tracers. Expressions for the relative rates of collagen synthesis and breakdown, which unlike mineral metabolism are considered not to be complicated by exchange phenomena, were based on¹⁴C-proline conversion to¹⁴C-hydroxyproline; the specific activity of the latter was determined. Both the mineral and the collagen specific activities reflected the rates and patterns of growth of the samples assayed; rapid growth and a short interval of time between formation and resorption of tissue in themetaphyseal bone which contains the cartilagineous growth plate, slow growth and an interval of time between formation and resorption of tissue indiaphyseal bone and incisor teeth which is longer than the 12 days of the experiment. However, in metaphyseal bone the specific activity collagen/mineral ratio dropped by one half during the 4–12 day interval in contrast to diaphyseal bone and incisor teeth in which no change in this ratio was observed during this period of time. The data indicate that collagen in the metaphyseal growth zone is removed by resorption before it has become fully mineralized, and that exchange is a relatively unimportant factor in the long term kinetics of bone mineral.

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Zusammenfassung Das Ausmaß, bis zu welchem Austausch- und Wiederverwendungsprozesse der mineralen Tracer die Messungen des mineralen Skelett-Auf- und Abbaues beeinflussen können, wurde ausgewertet; zu diesem Zweck wurde die Geschwindigkeit des Auftretens und Verschwindens von⁸⁵Sr und von¹⁴C-Prolin-Hydroxyprolin in Knochen und Zähnen von wachsenden Ratten während der 12 auf die simultane parenterale Injektion dieser Tracer folgenden Tage verglichen.Der Ausdruck für die relative Geschwindigkeit des Kollagen-Auf- und Abbaues, bei welchem im Gegensatz zum Mineralmetabolismus kein Mitwirken des Austauschphänomens vermutet wird, basiert auf der Umwandlung von¹⁴C-Prolin zu¹⁴C-Hydroxyprolin; die spezifische Aktivität des letzteren wurde bestimmt.Aus der spezifischen Aktivität des Minerals sowie jener des Kollagens konnten die Geschwindigkeit und die Art des Wachstums der untersuchten Proben ersehen werden, d.h.schnelles Wachstum und ein kurzes Zeitintervall zwischen Bildung und Resorption des Gewebes imKnochen der Metaphyse, die auch die knorpelige Wachstumsplatte enthält, und andererseitslangsames Wachstum und längeres Zeitintervall (länger als die 12 Tage des Experimentes) zwischen Bildung und Resorption des Gewebes imKnochen der Diaphyse und in den Schneidezähnen. Immerhin fiel die spezifische Aktivität des Kollagen/Mineral-Anteils im Knochen der Metaphyse während dem 4–12tägigen Zeitintervall auf die Hälfte, im Gegensatz zum Knochen der Diaphyse und der Schneidezähne, bei welchen während dieser Zeitspanne kein Unterschied in diesem Verhältnis beobachtet wurde.Diese Ergebnisse zeigen, daß Kollagen in der Wachstumszone der Metaphyse durch Resorption verschwindet, bevor es ganz mineralisiert ist, und daß der Austausch ein relativ unwichtiger Faktor in der Kinetik auf lange Sicht des Knochenminerals ist.