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991.
目的 探讨FOS蛋白在胶质瘤中的表达及其对胶质瘤细胞生长的影响.方法 用免疫组化染色法检测FOS蛋白在各级别胶质瘤组织中的表达水平.应用RNA干扰技术降低FOS表达后,应用四甲基偶氮唑盐微量酶反应比色法和流式细胞技术检测胶质瘤细胞的增殖和周期的改变;应用Transwell实验检测胶质瘤细胞侵袭能力的改变;采用Western印迹法检测FOS下游功能蛋白的变化.结果 胶质瘤组织中FOS的表达随着级别的增高而增高;抑制FOS的表达后,U87和U251细胞生长受抑制,细胞生长阻滞在G1期且细胞侵袭能力下降,下游的功能蛋白CyclinD1和MMP9表达水平降低.结论 FOS在胶质瘤中高表达;抑制其表达可以下调功能蛋白CyclinD1和MMP9的表达,进而调控细胞的生长和侵袭能力. 相似文献
992.
Neshat Eghbali Homam Naffakh-Moosavy Sanam Sadeghi Mohammadi Hossein Naderi-Manesh 《Dental materials》2021,37(3):547-558
ObjectiveMicro-nano scale surface modification of Ti-6Al-4V was investigated through the fascinated modern fiber engraving laser method. The process was performed at a high laser speed of 2000 mm/s, under different laser frequencies (20–160 kHz) and groove distances (0.5–50 μm).MethodsTopographic evaluations such as Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FE-SEM) were used to identify the quality and regularity of patterns. The proliferation of human osteoblast-like osteosarcoma cells (MG63) was analyzed by MTT assay for up to 72 h. Also, the plate counting method was used to quantify the viability potential of the modified surface against Escherichia coli bacteria.ResultsThe cellular viability of the sample modified at the laser frequency of 20 kHz and grooving distance of 50 μm increased up to 35 and 10% compared to the non-treated and control samples, respectively. In the case of the surface modification at lower grooving distances range between 0.5–50 μm, the maximum laser frequency (160 kHz) applied leads to lower pulse’s energies and less bacterial adhesion. Otherwise, at groove distances more than 50 μm, the minimum laser frequency (20 kHz) applied reduces the laser pulse overlaps, increases the cell adhesion and antibacterial properties.SignificanceSurface modification by the fiber engraving laser process significantly enhances the cell adhesion on the surface. As a result of such roughness and cell adhesion enhancement, the surface toxicity feature diminished, and its antibacterial properties improved. 相似文献
993.
目的:探讨血清可溶性血管细胞黏附分子-1(sVCAM-1)、可溶性细胞间黏附分子-1(sICAM-1)、血管性血友病因子(vWF)水平与冠心病(CHD)病变范围的相关性。方法:根据冠脉造影结果将87例患者分为CHD组(63例)和对照组(24例)。采用ELISA平行检测两组血清sVCAM-1、sICAM-1和vWF水平,酶法测定血脂水平,比较两组患者sVCAM-1、sICAM-1、vWF及血脂水平的差异,并进行相关性分析;以冠脉狭窄支数作为判断CHD病变范围的依据,探讨不同病变范围患者血清sVCAM-1、sICAM-1和vWF的水平变化。结果:CHD组血清sVCAM-1、sI-CAM-1、vWF水平显著高于对照组(P<0.01);血清sVCAM-1、sICAM-1和vWF水平与血脂水平之间无明显相关性(P>0.05);单支冠脉狭窄组血清sVCAM-1、sICAM-1水平显著低于多支冠脉狭窄组(P<0.05)。结论:CHD患者血清sV-CAM-1、sICAM-1和vWF水平升高,sVCAM-1、sICAM-1水平与CHD病变范围有关。 相似文献
994.
Hector Caballero-Flores Cleber Keiti Nabeshima Giovanna Sarra Maria Stella Moreira Victor Elias Arana-Chavez Márcia Martins Marques Manoel Eduardo de Lima Machado 《Dental materials》2021,37(7):e414-e425
ObjectiveAn ideal scaffold for endodontic regeneration should allow the predictableness of the new tissue organization and limit the negative impact of residual bacteria. Therefore, composition and functionalization of the scaffold play an important role in tissue bioengineering. The objective of this study was to assess the morphological, physicochemical, biological and antimicrobial properties of a new solid chitosan-based scaffold associated with gelatin, microparticulate dentin and genipin.MethodsScaffolds based on chitosan (Ch); chitosan associated with gelatin and genipin (ChGG); and chitosan associated with gelatin, microparticulate dentin and genipin (ChGDG) were prepared by using the freeze-drying method. The morphology of the scaffolds was analyzed by scanning electron microscopy (SEM). The physicochemical properties were assessed for biodegradation, swelling and total released proteins. The biological aspects of the scaffolds were assessed using human cells from the apical papilla (hCAPs). Cell morphology and adhesion to the scaffolds were evaluated by SEM, cytotoxicity and cell proliferation by MTT reduction-assay. Cell differentiation in scaffolds was assessed by using alizarin red assay. The antimicrobial effect of the scaffolds was evaluated by using the bacterial culture method, and bacterial adhesion to the scaffolds was observed by SEM.ResultsAll the scaffolds presented porous structures. The ChCDG had more protein release, adhesion, proliferation and differentiation of hCAPs, and bacteriostatic effect on Enterococcus faecalis than Ch and ChGG (p < 0.05).SignificanceThe chitosan associated with gelatin, microparticulate dentin and genipin has morphological, physicochemical, biological and antibacterial characteristics suitable for their potential use as scaffold in regenerative endodontics. 相似文献
995.
目的 制备并鉴定NPM1单克隆抗体.方法 利用纯化的NPM1融合蛋白作为抗原,通过常规的细胞融合技术制备杂交瘤细胞,用间接ELISA法筛选能出产生抗NPM1单克隆抗体的阳性细胞株,对抗NPM1单克隆抗体的特性进行分析.结果 筛选出1株产生抗NPM1单克隆抗体的杂交瘤细胞株,产生的抗体为IgGl亚类,效价达1∶720000;纯化后经SDS-PAGE显示两条蛋白条带,纯度达95%以上,相对分子质量约为50000和25000,与单一抗体重链、轻链分子大小相符.免疫组化证实,纯化的2G7抗NPM1单克隆抗体可检测出NPM1在结直肠癌表达,阳性位点为细胞核.结论 制备的抗NPM1单克隆抗体可用于NPM1蛋白功能的研究与临床检测. 相似文献
996.
目的探讨Cpne5蛋白在SH-SY5Y细胞凋亡中表达量的变化。方法显微镜观察细胞形态及流式细胞术检测凋亡率,鉴定A23187诱导SH-SY5Y细胞凋亡及血清剥夺诱导凋亡的模型;免疫印迹法检测两种凋亡过程中Cpne5蛋白表达量的变化。结果 10μmol/L A23187诱导SH-SY5Y细胞24h,细胞出现皱缩、凋亡率增加。A23187诱导0.5h,Cpne5蛋白表达量即出现明显的上升,持续至12h;在24h时Cpne5蛋白表达量回落至诱导前水平。血清剥夺72h的SH-SY5Y细胞24份,凋亡率为23.2±2.1%,与对照组1.1±0.1%比,差异有统计学意义(P〈0.01)。免疫印迹结果表明,SH-SY5Y细胞分别经血清剥夺1h、6h、12h、24h、72h对Cpne5蛋白表达量无明显变化。结论 A23187诱导SH-SY5Y细胞凋亡早期Cpne5蛋白表达量有显著变化;提示Cpne5基因可能参与凋亡调控的钙信号通路。 相似文献
997.
目的 探究DZIP1通过Wnt/β-catenin信号通路对口腔鳞状细胞癌增殖、迁移和侵袭的影响。方法 实时荧光定量PCR和Western blot检测DZIP1和Wnt/β-catenin信号通路相关基因mRNA表达和蛋白表达,CCK-8检测细胞活力,克隆形成实验检测口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)细胞增殖能力,Transwell实验检测细胞迁移和侵袭能力。结果 与人口腔角质形成细胞相比,人OSCC细胞系TSCCA,Tca8113和SCC25中DZIP1的mRNA表达和蛋白表达均显著升高;与阴性对照组(negative control,NC)相比,敲低DZIP1显著降低SCC25细胞Wnt/β-catenin信号通路相关基因的mRNA表达和蛋白表达(P<0.05),显著降低细胞活力(P<0.05),显著抑制细胞增殖(P<0.05),显著降低细胞迁移和侵袭能力(P<0.05),LiCl显著升高SCC25细胞Wnt/β-catenin信号通路相关基因的mRNA表达和蛋白表达(P<0.05),显著升高细胞活力(P<0.05),显著促进细胞增殖(P<0.05),显著升高细胞迁移和侵袭能力(P<0.05);与si-DZIP1组相比,si-DZIP1+LiCl显著升高SCC25细胞Wnt/β-catenin信号通路相关基因的mRNA表达和蛋白表达(P<0.05),显著升高细胞活力(P<0.05),显著促进细胞增殖(P<0.05),显著升高细胞迁移和侵袭能力(P<0.05)。结论 DZIP1通过影响Wnt/β-catenin信号通路促进口腔鳞状细胞癌增殖、迁移和侵袭。 相似文献
998.
999.
Meong Hi Son Dong Hwan Kim Soo Hyun Lee Keon Hee Yoo Ki Woong Sung Hong Hoe Koo Ju Youn Kim Eun Joo Cho Eun Suk Kang Dae Won Kim 《Journal of Korean medical science》2013,28(2):220-226
Although the number of studies using tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/autoSCT) for the treatment of high-risk pediatric solid tumors has been increasing, documentation of hematologic recovery after tandem HDCT/autoSCT is very limited. For this reason, we retrospectively analyzed the hematologic recovery of 236 children with high-risk solid tumors who underwent tandem HDCT/autoSCT. The median numbers of CD34+ cells transplanted during the first and second HDCT/autoSCT were 4.3 × 106/kg (range 0.6-220.2) and 4.1 × 106/kg (range 0.9-157.6), respectively (P = 0.664). While there was no difference in neutrophil recovery between the first and second HDCT/autoSCT, platelet and RBC recoveries were significantly delayed in the second HDCT/autoSCT (P < 0.001 and P < 0.001, respectively). Delayed recovery in the second HDCT/autoSCT was more prominent when the number of transplanted CD34+ cells was lower, especially if it was < 2 × 106/kg. A lower CD34+ cell count was also associated with increased RBC transfusion requirements and a higher serum ferritin level after tandem HDCT/autoSCT. More CD34+ cells need to be transplanted during the second HDCT/autoSCT in order to achieve the same hematologic recovery as the first HDCT/autoSCT. 相似文献
1000.
Bumsoo Park Byong Chang Jeong Seong Il Seo Seong Soo Jeon Han Yong Choi Hyun Moo Lee 《Journal of Korean medical science》2013,28(2):227-236
The association of body mass index, smoking, and blood pressure, which are related to the three well-established risk factors of renal cell carcinoma, and survival in patients with renal cell carcinoma is not much studied. Our objective was to evaluate this association. A cohort of 1,036 patients with low stage (pT1 and pT2) renal cell carcinoma who underwent radical or partial nephrectomy were enrolled. We retrospectively reviewed medical records and collected survival data. The body mass index, smoking status, and blood pressure at the time of surgery were recorded. Patients were grouped according to their obesity grade, smoking status, and hypertension stage. Survival analysis showed a significant decrease in overall (P = 0.001) and cancer-specific survival (P < 0.001) with being underweight, with no differences of smoking status or perioperative blood pressure. On multivariate analysis, perioperative blood pressure ≥ 160/100 mmHg (HR, 2.642; 95% CI, 1.221-5.720) and being underweight (HR, 4.320; 95% CI, 1.557-11.984) were independent predictors of overall and cancer-specific mortality, respectively. Therefore, it is concluded that being underweight and perioperative blood pressure ≥ 160/100 mmHg negatively affect cancer-specific and overall survival, respectively, while smoking status does not influence survivals in patients with renal cell carcinoma. 相似文献