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排序方式: 共有4162条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2019,37(47):6987-6995
Vero cells are nowadays widely used in the production of human vaccines. They are considered as one of the most productive and flexible continuous cell lines available for vaccine manufacturing. However, these cells are anchorage dependent, which greatly complicates upstream processing and process scale-up. Moreover, there is a recognized need to reduce the costs of vaccine manufacturing to develop vaccines that are affordable worldwide. The use of cell lines adapted to suspension growth contributes to reach this objective.The current work describes the adaptation of Vero cells to suspension culture in different serum free media according to multiple protocols based on subsequent passages. The best one that relies on cell adaption to IPT-AFM an in-house developed animal component free medium was then chosen for further studies. Besides, as aggregates have been observed, the improvement of IPT-AFM composition and mechanical dissociation were also investigated.In addition to IPT-AFM, three chemically defined media (CD293, Hycell CHO and CD-U5) and two serum free media (293SFMII and SFM4CHO) were tested to set up a serum free culture of the suspension-adapted Vero cells (VeroS) in shake flasks. Cell density levels higher than 2 × 106 cells/mL were obtained in the assessed conditions. The results were comparable to those obtained in spinner culture of adherent Vero cells grown on Cytodex 1 microcarriers.Cell infection with LP-2061 rabies virus strain at an MOI (Multiplicity of Infection) of 0.1 and a cell density of 8 ± 0.5 × 105 cells/mL resulted in a virus titer higher than 107 FFU/mL in all media tested. Nevertheless, the highest titer equal to 5.2 ± 0.5 × 107 FFU/mL, was achieved in IPT-AFM containing a reduced amount of Ca++ and Mg++. Our results demonstrate the suitability of the obtained VeroS cells to produce rabies virus at a high titer, and pave the way to develop VeroS cells bioreactor process for rabies vaccine production. 相似文献
2.
《Journal of bodywork and movement therapies》2020,24(1):154-164
IntroductionBioelectrical impedance analysis (BIA) has been used to evaluate cellular health and integrity through bioelectrical indicators. In the sporting context, monitoring these indicators can be useful to assess the quality and vitality of cells and body tissues.ObjectiveThe aim of this systematic review was to investigate indicators of cellular health and integrity evaluated by BIA in athletes.MethodsSearches were performed in December 2017 in the Lilacs, Medline, PubMed, Science Direct, Scielo, Scopus, SPORTDiscus, and Web of Science databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.ResultsThe searches retrieved 31 articles (30 involving professional athletes and one involving university athletes). In longitudinal studies (n = 15), the bioelectrical parameters directly associated with cellular health and integrity were extracellular water (ECW), phase angle (PA), BIA vector analysis (BIVA), crude reactance data (Xc), resistance (R), and ECW/BCM ratio. Regarding the findings of cross-sectional studies (n = 16), the investigated parameters (ECW, PA, BIVA, Z, BCM, and ECW/BCM) were directly associated with gender, age, sports performance level, modality, and game position.ConclusionsIn the included studies, the cellular health and integrity indicators were: Z, Xc, R, total water, intracellular water, ECW, PA, BIVA, BCM, and ECW/BCM. 相似文献
3.
4.
目的:研究大黄乙醇提取物的抗新城疫病毒(NDV)作用。方法:采用体外细胞培养的方法研究大黄乙醇提取物对NDV感染的拮抗作用。结果:20g/L剂量大黄乙醇提取物对BHK21细胞未有任何毒性作用;0.5g/L大黄对NDV所致CPE有明显的抑制作用;大黄可预防NDV感染,并对NDV的复制动力学有明显影响。结论:大黄乙醇提取物具有明显的抗NDV作用。 相似文献
5.
Antonio Gigante Claudia Bevilacqua Andrea Ricevuto Monica Mattioli-Belmonte Francesco Greco 《Knee surgery, sports traumatology, arthroscopy》2007,15(1):88-92
The implantation of chondrocytes, seeded on matrices such as hyaluronic acid or collagen membranes, is a method that is being widely used for the treatment of chondral defects. The aim of the present study was to evaluate the distribution, viability and phenotype expression of the cells seeded on a collagen membrane just at the time of the implantation. Twelve patients who were suffering from articular cartilage lesions were treated by the MACI® procedure. The residual part of each membrane was tested by colorimetric assay (MTT) and histochemical and ultrastructural analyses were carried out. In all of the samples a large number of viable cells, quite homogenously distributed, was detected. The cells expressed the markers of the differentiated hyaline chondrocytes. These data reassure in that the MACI procedure provides a suitable engineered tissue for cartilage repair, in line with the clinical evidences emerging in the literature. 相似文献
6.
目的观察丙丁酚对载脂蛋白E-/-小鼠主动脉粥样硬化斑块形成及主动脉凝集素样氧化型低密度脂蛋白受体1表达的影响,以探讨丙丁酚调节血脂以外的可能的抗动脉粥样硬化作用机制。方法将21只4周龄的雄性载脂蛋白E-/-小鼠随机分成基础饮食对照组、高脂饮食对照组和高脂饮食加丙丁酚组 相似文献
7.
I. HELIN A. WIDELL S. BORULF M. WALDER U. ULMSTEN 《Acta paediatrica (Oslo, Norway : 1992)》1987,76(2):234-238
ABSTRACT. During the late winter of 1983, 16 newborns with vague symptoms of failure to thrive, reluctance to feed and a slight rise in body temperature, were found to have meningitis caused by Coxsackievirus A-14. The cerebrospinal fluid showed pleocytosis with polymorphonuclear cells in excess but was otherwise normal. The clinical course was uneventful in all infants, but two of them demonstrated clinical signs of incipient cerebral oedema during the acute phase of the illness. An electroencephalogram (EEG) during the initial course of the disease and at nine months of age was normal in all. During a follow-up period of 21/2 years they all developed normally and no sequelae were noted. The presentation also demonstrates the usefulness of Vero cells for the propagation of the responsible virus. 相似文献
8.
体外培养诱导外周血淋巴细胞促进大鼠面神经再生的实验研究 总被引:1,自引:0,他引:1
目的:通过在神经缺损处局部回输体外分离培养纯化的淋巴细胞,了解此种方法促进面神经损伤修复的效果。方法:将20只Wistar大鼠的面神经颊支剪断并立即缝合(其余3支反折缝合)制成面神经损伤模型大鼠,将其分成淋巴细胞组和对照组,每组10只,每组再分成2周组和8周组。淋巴细胞组局部回输体外分离培养的外周血淋巴细胞,对照组作对照。于2周和8周测定面神经颊支-触须肌复合动作电位传导速度,辣根过氧化物酶(HRP)神经逆行示踪测定面神经核团的神经元阳性数目。结果:淋巴细胞组面神经颊支-触须肌复合动作电位传导速度8周时为0.64±0.07,与对照组(0.56±0.07)相比,差异有统计学意义(P<0.05)。HRP神经逆行示踪测定面神经核团神经元阳性数目,淋巴细胞组2周及8周与对照组同时间段相比差异均无统计学意义(均P>0.05)。结论:体外分离培养纯化的淋巴细胞在局部应用于神经损伤处对面神经再生修复可起一定的促进作用。 相似文献
9.
深低温冷冻肌腱细胞活性的研究 总被引:5,自引:0,他引:5
目的研究深低温冷冻方法对肌腱细胞活性的影响,比较程序性降温和普通深低温冷冻法对腱细胞活性的影响.方法纯种SD大鼠24只(出生21 d),随机分为3组,取双侧跟腱.新鲜肌腱对照组(A),常规深低温冷冻组(B),程序性降温深低温冷冻组(C).采用相同的方法对3组肌腱细胞进行细胞培养.相差显微镜观察原代和传代后细胞的生长,绘制细胞的生长曲线,考察细胞的活性;对细胞进行成纤维细胞染色、胶原染色和对细胞进行形态观察(扫描电镜);水解法定量分析细胞培养基中羟脯氨酸浓度的变化,检测细胞合成胶原的能力.结果原代细胞培养时A组细胞的生长速度快于B组和C组(P<0.01),C组细胞的生长速度快于B组(P<0.01),这种生长速度的差异在细胞传代后消失.细胞的形态学和组织学符合成纤维细胞形态.3组细胞培养基中羟脯氨酸浓度变化的差异无统计意义(P>0.05).结论经深低温冷冻处理的肌腱中仍存在具有活性的腱细胞,但数量显著少于新鲜肌腱中活细胞的数量.应用计算机控制程序性慢速降温方法处理的肌腱其活细胞的数量有所提高,但仍低于新鲜肌腱中活细胞的数量. 相似文献
10.
目的: 观察细胞内游离Ca2+([Ca2+]i)在培养的不同发育阶段皮层神经元无镁诱导惊厥性损伤中的作用,探讨惊厥性脑损伤年龄依赖性的可能机制.方法:体外培养6 d、17 d的胚胎大鼠皮层神经元用无镁细胞外液处理3 h,或于无镁处理前用NMDA(N-甲基-D-门冬氨酸)受体拮抗剂或Ca2+通道阻滞剂预处理,用MTT代谢率测定的方法检测神经元损伤,以Fluo-3作标记用激光共聚焦显微镜扫描的方法检测[Ca2+]i.结果:体外培养6 d、17 d的神经元单纯无镁组MTT代谢率较同期对照组降低.应用MK-801 10 μmol*L-1、AP-5 50 μmol*L-1、尼莫地平10 μmol*L-1预处理后再给无镁处理,培养6 d、17 d的神经元MTT代谢率均不同程度高于同期单纯无镁组.培养6 d、17 d的神经元相对荧光强度之间差异有显著性,两者与基线荧光强度比较差异亦有显著性.应用上述各种拮抗剂后,[Ca2+]i改变的峰值均明显低于同期单纯无镁组.结论: 在体外不同发育阶段的神经元,短暂无镁处理诱导惊厥样放电所引起的神经元线粒体功能损伤以及[Ca2+]i改变程度不同.这种[Ca2+]i改变的年龄依赖性可能是惊厥导致神经元损伤的年龄依赖性的机制之一.NMDA受体-Ca2+通道激活是导致这种[Ca2+]i改变及神经元损伤的关键环节. 相似文献