Neuroprotection of progesterone on retinal ganglion cells in chronic ocular hypertension model rats / 吉林大学学报(医学版)

Objective To observe the protective effect of progesterone(PROG) on rat retinal ganglion cells(RGCs) in chronic ocular hypertention models.Methods The chronic ocular hypertention rat model was made by cauterizating three episcleral veins.Rats were divided into control group,high level PROG group,middle level PROG group,low level PROG group according to different concentrations of PROG injected intraperitoneally.The left eye was model eye and the right eye was control eye.Three months later,the animals were executed and the eyeballs were enucleated.The RGCs were detected by HE staining and Thy-1.1 immunohistological staining.The apoptosis of RGCs was detected by TdT-dUDP terminal nick end-labeling(TUNEL) technique.Results The number of RGCs of model eyes in high level PROG injection group was more than those in control group,low level and middle level groups(P

Influence of different contact ways and extracting conditions on the hemolytic effect of biomaterials / 生物医学工程学杂志

This assay was aimed to evaluate the influence of different contact ways and extracting conditions on the hemolytic effect of biomaterials. Using direct contact method and extract contact method, we assessed the hemolytic effect of PDLLA and PVC. The extracting conditions included: 37 degrees C 24 h, 37 degrees C 72 h, 37 degrees C 120 h, 50 degrees C 72 h, and 70 degrees C 24 h. After the material or extract had been in contact with the diluted blood of rabbit for certain times, the hemolysis rate was calculated. The results for PDLLA showed there were some differences between direct contact and extract contact at 37 degrees C for different extraction time (P < 0.05), but the hemolysis rates, lower than 5%, were in accord with the requirements of medical devices. However, under the condition of 50 degrees C and 70 degrees C, there were significant differences when extract contact method was compared with direct method (P < 0.01). For PVC, there was no statistically significant difference under all conditions (P > 0.05). Our conclusions: (1) Under the extracting condition of 37 degrees C from 24 h to 120 h, the soluble part of PDLLA and PVC that might influence erythrocyte did not dissolve considerably. (2) Under the extracting condition of 50 degrees C and 70 degrees C, the hemolysis rate may remarkably vary with the chemical characteristics of tested materials; (3) As to an unknown material, it is advisable to adopt two methods at the same time, one for direct contact and the other for extracontact. Thus the hemolytic effect of biomaterials can be evaluated from physical and chemical angles. (4) In case that the chemical property of the sample can endure the test, the extracting condition at 50 degrees C and 70 degrees C may be of benefit to assessing the hemolytic effect of biomaterials. (5) The extract contact method as a supplemental test of direct contact method is of realistic significance.

Evaluation of the short-term biocompatibility of a new kind of hydrogel prosthetic nucleus / 中国组织工程研究

Aim To evaluate the short-term biocompatibility of a newkind of prosthetic nucleus-Evergel, which is made from the modifiedpolyvinyl alcohol hydrogel. Methods According to China national standardGB/T16886 documents, the toxicity of Evergel prosthetic nucleus materialwas investigated by the cytotoxicity test, sensitization test, haemolysis test,Ames test, mice marrow micronucleus test and chromosome aberration test ofmammalian cell in vitro. Results This material had no cytoxicity, no sen-sitivity, no obvious haemolysis, and no mutagencity in Ames test, micemarrow micronucleus test and chromosome aberration test of mammalian cellin vitro. Conclusion The Evergel prosthetic nucleus has a good biocom-patibility and can be used clinically.