Use of Human Fibroblasts Grown on Microcarriers for Formation of Connective Tissue Equivalent

Living equivalents of tissues, specifically those produced on the basis of fibroblasts and collagen gel, are widely used for repair of organ and tissues defects. In clinical practice, it is more convenient to use the fibroblasts grown on microcarriers or such a connective tissue equivalent when the fibroblasts on microcarriers are embedded in collagen gel. We studied the properties of a connective tissue equivalent produced by embedding the fibroblasts grown on microcarriers in collagen gel for its prospective use in clinical practice. According to our results, the optimal time of use of the living tissue equivalent amounts to three–four days after embedding of fibroblasts on microcarriers in gel. At that time, contraction only begins, which facilitates manipulations with the gel.     

VerO细胞在气升式反应器中的微载体培养

哺乳动物细胞的大规模培养是生产许多医学上重要生物制品的一种主要方法之－⑴。很多有工业价值的动物细胞都是贴壁细胞,必须附着在一定的表面上才能生长,微载体培养是一种有效的体系⑵。用于微载体培养的反应器多为搅拌式反应器,近年来,流化床式反应器越来越引起生化工程学家的重视。有希望用于大规模动物细胞培养的主要是液升和气升式。液升式反应器的优点是培养液可以间接氧饱和,气泡和细胞不直接接触。在气升式流态反应器中,气泡与细胞直接接触,其优点是操作方便,设备筒单。本文报道通过气升流态化反应器实现高密度贴壁细胞培养工艺条件的研究。     

大孔吸附树脂吸附链霉菌702抗真菌活性物质工艺

研究大孔吸附树脂吸附链霉菌702抗真菌活性物质的工艺条件。采用5种不同大孔吸附树脂吸附链霉菌702发酵液提取液中抗真菌活性物质,选择吸附效果较佳树脂进行吸附条件优化,以桔青霉为指示菌,纳他霉素为对照抗生素．采用“管碟法”测定抗真菌活性物质含量。结果发现,XAD18树脂吸附效果较好,获得优化吸附条件：上样液pH6,NaCl质量浓度10g/L,上样量22．63mg／g湿树脂,吸附流速2．5mL／min,水洗体积180mL,洗脱流速1．5mL／min,洗脱剂为体积分数10％、50％和90％的甲醇,洗脱方式为梯度洗脱。在确定的工艺条件下XAD18对链霉菌702抗真菌活性物质的吸附率可达90％,洗脱率可达75％,回收率可达80％。     

Engineered Smooth Muscle Tissues: Regulating Cell Phenotype with the Scaffold

Culturing cells on three-dimensional, biodegradable scaffolds may create tissues suitable either for reconstructive surgery applications or as novel in vitro model systems. In this study, we have tested the hypothesis that the phenotype of smooth muscle cells (SMCs) in three-dimensional, engineered tissues is regulated by the chemistry of the scaffold material. Specifically, we have directly compared cell growth and patterns of extracellular matrix (ECM) (e.g. , elastin and collagen) gene expression on two types of synthetic polymer scaffolds and type I collagen scaffolds. The growth rates of SMCs on the synthetic polymer scaffolds were significantly higher than on type I collagen sponges. The rate of elastin production by SMCs on polyglycolic acid (PGA) scaffolds was 3.5 +/- 1.1-fold higher than that on type I collagen sponges on Day 11 of culture. In contrast, the collagen production rate on type I collagen sponges was 3.3 +/- 1.1-fold higher than that on PGA scaffolds. This scaffold-dependent switching between elastin and collagen gene expression was confirmed by Northern blot analysis. The finding that the scaffold chemistry regulates the phenotype of SMCs independent of the scaffold physical form was confirmed by culturing SMCs on two-dimensional films of the scaffold materials. It is likely that cells adhere to these scaffolds via different ligands, as the major protein adsorbed from the serum onto synthetic polymers was vitronectin, whereas fibronectin and vitronectin were present at high density on type I collagen sponges. In summary, this study demonstrates that three-dimensional smooth muscle-like tissues can be created by culturing SMCs on three-dimensional scaffolds, and that the phenotype of the SMCs is strongly regulated by the scaffold chemistry. These engineered tissues provide novel, three-dimensional models to study cellular interaction with ECM in vitro.     

大孔树脂吸附法提纯苦楝素的研究

研究了大孔树脂吸附法从苦楝树皮的提取液中提纯苦楝素的工艺条件及参数,并筛选出较为理想的大孔吸附树脂。研究结果表明,S-8型吸附树脂的静态饱和吸附量明显大于AB-8型和NKA-9型。该树脂吸附提纯苦楝素的优化吸附条件为吸附温度40℃,溶液pH值8．0,上柱液质量浓度9．127mg／mL,溶液流速2BV／h;优化的解吸条件为：洗脱剂为70％乙醇-水溶液,溶液流速1BV／h,洗脱剂用量为8倍量树脂体积。在优化条件下,可以得到含量达75．2％的苦楝素提取物,表明S-8树脂对苦楝素有良好的吸附选择性。     

大孔吸附树脂分离纯化香叶木苷

比较了D-101、D-140、AB-8、XAB-8、D312、聚酰胺等6种吸附树脂对蓬子菜中活性成分香叶木苷diosmin的吸附和洗脱条件,在静态吸附研究的基础上,进行了动态实验,并且利用二次吸附对该成分进行了纯化。结果表明AB-8树脂对diosmin的吸附量大、吸附速度快、解吸容易、富集分离效果好。利用聚酰胺进行二次纯化,得到纯度95%以上的diosmin。     

磁性大孔树脂对苹果渣多酚的吸附-解吸效能

以苹果渣多酚类化合物为吸附模型,制备一种可有效吸附分离苹果渣多酚的磁性树脂,研究其吸附、解吸效能,并就吸附和解吸效能、使用次数与普通大孔树脂进行比较。结果显示,5种普通树脂中D280、H103、AB-8对苹果渣多酚的吸附率均高于80%,AB-8、D3520树脂对苹果渣多酚的解吸率均高于90%,AB-8树脂的吸附率和解吸率最好;磁性大孔树脂吸附0.5 h后即可达到吸附平衡,吸附平衡后剩余液多酚质量浓度低于AB-8树脂吸附平衡后剩余液多酚质量浓度,吸附效能明显优于AB-8树脂;磁性大孔树脂解吸效能也略优于AB-8树脂;使用4 次后,磁性大孔树脂的吸附率仍然高于70%,稳定性优于AB-8树脂。可见,磁性大孔树脂是一种良好的苹果渣多酚吸附剂,有较好的工业化应用前景。     

The use of macroporous gelatin carriers for the cultivation of mammalian cells in fluidised bed reactors

A fluidised bed system for the cultivation of mammalian cells on a new type of macroporous gelatin microcarrier is described. The volumetric cell densities achieved under controlled conditions for two standard cell lines (VERO, CHO) were one order of magnitude higher compared to conventional techniques using spherical microcarriers. The system can be potentially used for both anchorage dependent and independent cells.     

大孔吸附树脂分离富集苜蓿皂甙的研究

本项工作以对苜蓿皂甙的吸附量和解吸率为指标筛选大孔吸附树脂。研究结果表明,X-5吸附树脂具有较好的吸附性能和解吸效果。研究应用正交试验方法进一步对大孔吸附树脂分离纯化苜蓿皂甙的工艺条件进行试验分析,确定苜蓿皂甙分离富集的最佳操作条件为:上样浓度8mg/mL,色谱柱的径高比1∶7,药材-树脂比例1∶3;吸附完全后,先以水洗脱,除去杂质,再以50%乙醇洗脱,可以得到纯度较好的苜蓿皂甙。