RESUMEN
Myocytes in the pulmonary veins (PV) play a pivotal role in the development of paroxysmal atrial fibrillation (AF). It is therefore important to understand physiological characteristics of these cells. Studies on these cells are, however, markedly impeded by the fact that single PV myocytes are very difficult to obtain due to lack of effective isolation methods. In this study, we described a novel PV myocyte isolation method. The key aspect of this method is to establish a combination of retrograde heart perfusion (via the aorta) and anterograde PV perfusion (via the pulmonary artery). With this simultaneous perfusion method, a better perfusion of the PV myocytes can be obtained. As results, the output and viability of single myocytes isolated by simultaneous heart and PV perfusion method were increased compared with those in conventional retrograde heart perfusion method.
Asunto(s)
Animales , Conejos , Fibrilación Atrial , Separación Celular , Corazón , Células Musculares , Perfusión , Venas PulmonaresRESUMEN
Human acidic fibreblast growth factor (haFGF) was a kind of cell growth factor with wide bio-activity on cell from mesectoderm and neuro-ectoderm.In this paper, the effect of acetate concentration on the growth and expression of recombinant human acidic fibroblast growth factor mutant system E.coli BL21(DE3)/pET3C-haFGF was investigated. Four fed-batch modes: batch-fed, batch-DO static balance, DO static balance-glucose starvation, and pH-static state were investigated. The accumulation of acetate during the fermentation course was effectively inhibited. The OD600nm value was about 22, after purification, the soluble rhaFGF yielded 450mg/L. During the fermentation, no special ways such as pure oxygen, pressure were adopted, thus the established process would be easily scaled up for industry purpose.
Asunto(s)
Humanos , Ácido Acético , Metabolismo , Reactores Biológicos , Microbiología , Técnicas de Cultivo de Célula , Métodos , Medios de Cultivo , Escherichia coli , Genética , Metabolismo , Fermentación , Factor 1 de Crecimiento de Fibroblastos , Genética , Proteínas Mutantes , Genética , Proteínas Recombinantes , GenéticaRESUMEN
The optimum culture conditions for Acetobacter xylinum NUST4 which produces bacterial cellulose(BC) were obtained by uniform design method.BC production was dependent on MgSO_(4)?7H_(2)O,FeSO_(4)?7H_(2)O and cosubstrates such as p-aminobenzoic acid,nicotinamide,d-Biotin and ethanol.The optimal medium contained glucose 24g,sucrose 22g,peptone 16g,HAc 2.4mL,Na_(2)HPO_(4)?12H_(2)O 3.5 g,KH_(2)PO_(4)?H_(2)O 1 g,MgSO_(4)?7H_(2)O 6 g,FeSO_(4)?7H_(2)O 0.015g,nicotinamide 0.003 g,d-Biotin 0.02g and ethanol 20mL in 1L culture medium.BC yield reached 9.87g(the dried weight) in stationary culture for 7 days,which was 12-fold higher than that in the S-H medium.
RESUMEN
A rapid screening model for biosurfactant-producing strains is described in this paper, according as biosurfac-tant can make the blood-plate hemolysis and produce the blue cycles in blue-glue-plate. 12 microorganisms have been got from soil and water samples sampled from oil field and refinery using this model, and one of them can produce the glyco-lipid biosurfactant, which can depress the interfacial tension of water from 71. 3mN/m to 30. 5mN/m, and yield is 6.5 g/L.