A novel bioassay to assess bioactivity of PEG-rhGH using Nb2-11 cells / 药学学报

In this study, we established a novel bioassay to determine the activity of polyethylene glycolated recombinant human growth hormone (PEG-rhGH) using Nb2-11 cells. We performed experimental condition optimization and methodological verification, and then detected the relative potency of PEG-rhGH products using this method. We demonstrated that the bioactivity of PEG-rhGH in promoting Nb2-11 cell proliferation displays a dose-response relationship, which conformed to the four-parameter model. Using PEG-rhGH reference as a control, we analyzed the relative potency of six batches of PEG-rhGH products, as well as linearity, regression and parallelism of the obtained curves. The relative potency of six batches of PEG-rhGH products was 95% to 105%. These results implied that the new bioassay established may be employed in quality control of PEG-rhGH products.

Efficacy of Human Platelet Rich Fibrin Exudate vs Fetal Bovine Serum on Proliferation and Differentiation of Dental Pulp Stem Cells

BACKGROUND AND OBJECTIVES: The imperative role of dental pulp stem cells (DPSCs) in regenerative therapy demands an in-vitro expansion which must deal with the safety and ethical problems associated with fetal bovine serum (FBS). The primary aim of this study was to compare the effects of human platelet rich fibrin (hPRF) exudate Vs FBS on proliferation and osteodifferentiation of human dental pulp stem cells (hDPSCs). The secondary one was to determine the optimum concentration of hPRF exudate inducing hDPSCs proliferation and osteodifferentiation. METHODS: The direct method was used to prepare hPRF exudate. hDPSCs were isolated from impacted mandibular third molars of twelve donors by the outgrowth method. For cell viability and proliferation rate testing, 96 well plates were used and the assay was done in duplicate and the trial repeated four times under the same conditions. Six wells were used to contain 10% FBS, serum free media, 1%, 5%, 10% and 20% concentrations of hPRF exudates, respectively. The proliferation assay was carried out by MTS tetrazolium cell proliferation assay kit and Elisa reader. The study design for osteodifferentiation protocol was exactly as the proliferation one and instead the assay was carried out by alizarin red with Elisa reader. RESULTS: Compared to 10% FBS, 10% hPRF exudate was the optimum concentration for hDPSCs proliferation, while 1% hPRF exudate was the optimum concentration for osteodifferentiation of hDPSCs. CONCLUSIONS: Avoiding the risk of zoonosis which may be occurred with FBS, it is recommended to use 10% hPRF exudate for proliferation and 1% for osteodifferentiation.

Study on Estrogenic Effect of Organic Extracts of Reclaimed Water in Tianjin / 环境与健康杂志

Objective To study the estrogenic effect of organic extracts of effluent samples from different treatment stages in Tianjin reclaimed water treatment plant. Methods Reverse phase C-18 solid-phase extraction (RP-C18SPE) was used for the extraction of target compounds from water samples. Then, a simplified proliferation test with human estrogen receptor-positive MCF-7 breast cancer cell and recombined yeast assay were applied to assess the estrogenic effect in effluent samples from different treatment stages in Tianjin reclaimed water treatment plant. Results The amount of extracts of reclaimed water inducing the maximum effect in cell proliferation assay was equal to that from 1.00 ml primary water. In recombined yeast assay, the amount of extracts of reclaimed water inducing maximum ?-galactosidase activity was equal to that from 20.00 ml primary water. Conclusion The effluent of reclaimed water treatment plant still shows estrogenic effect though slightly reduced.