Biosorption of Pb(II) by biomass of KC-2: kinetic, equilibrium and characteristic studies.

Performance and characteristics of biosorption of Pb(II) had been studied in a batch system using the fungal strain biomass, KC-2. The biosorption performance was investigated by analysing the effects of such factors as the initial pH, initial Pb(II) concentration, and contact time at 303 K. The maximum Pb(II) adsorption was obtained at pH 5.0. The experimental data were described by the pseudo first-order, pseudo second-order and intraparticle diffusion kinetic models, and were closely followed the pseudo second-order kinetic model. The equilibrium experimental data were well fitted to Langmuir model and the maximum biosorption capacity was 84.03 mg g(-1). The adsorption mechanism was examined by FTIR, SEM and EDAX analysis. Results indicated that carboxylic, hydroxyl and amine groups were involved in the biosorption and ion exchange mechanism existed.

[Research of gene expression profile of liver tissue in rat sepsis model].

OBJECTIVE: To screen differentially expressed genes of liver tissue in rat sepsis model and analyze them in terms of functions. METHODS: Thirty male Wistar rats were randomly divided into model group and blank control group with 15 rats in each group. Cecal ligation and puncture (CLP) was used to reproduce rat sepsis model, gene expression profile microarray that contains 4 096 rat cDNA clones was used to detect the change in gene expression pattern of rat liver tissue 24 hours after CLP, then differentially expressed genes that high correlated to sepsis were screened, and the functions of these genes were analyzed by means of related computer software. RESULTS: Compared to the controls, gene expression of 522 genes in rat sepsis model were changed 24 hours after CLP, accounting for 12.7%, among them 244 gene expression down-regulated, and 278 gene expression up-regulated. CONCLUSION: Multiple organ dysfunction syndrome (MODS) induced by sepsis involves to a series of gene differential expressions, such as cell cycle and control related genes, cell apoptosis genes, immunity related genes, genes concerning energy metabolism, blood system related genes, cancer related genes, growth factor genes, acute stress reaction related genes etc. Gene microarray technique can be used to comprehensively study gene expression profile in rat sepsis model, in order to find new research objectives and gene therapy strategies for sepsis.