[Objective]To evaluate the interface biomechanical characteristics of a new kind of hydroxyapatite coating.[Method] Ten dogs underwent hermiarthroplasty of hip joint and were divided into 2 groups.One group was placed in Ti-6AI-4V femoral stem(Ti hip group),the second group was placed in HA-coated femoral stem(HA hip group).The second method was rod implant in condyles in both legs of each dog.Four matured dogs were selected.Eight Ti-6AI-4V rods(Ti rod group)were placed in lateral and medial condyle in left leg of each dog and eight HA-coated rods(HA rod group)were implanted in that of right leg of each dog.The dogs were sacrificed at 12 weeks after operation,and then the interface shear strength and imerface histological changes were evaluated.[Result]The Pust-out test showed that the average interface shear strengths of Ti hip group and HA hip group were(2.58?1.56)Mpa and(7.57?1.03)Mpa respectively.The interface shear strengths of HA hip group was significantly higher than that of Ti hip group(P

AIM To establish an animal experimental model for study on prevention of cisplatin toxicity and explore the possible mechanisms of the toxicity induced by cisplatin administration. METHODS Cisplatin was administered i.p consecutively for five days to male mice weighted from 28 to 30 g. The toxic effects induced by different doses of cisplatin on hearing, liver and kidney were determined. RESULTS Dose dependent decrease of body weight, abnormality of kidney and liver coefficients, levels of BUN and activities of ALT in serum were induced by cisplatin administration. Furthermore, Levels of GSH, activities of GSH Px and SOD increased significantly in kidney. Reversely, levels of GSH, activities of GSH Px and SOD in liver decreased and levels of LPO increased significantly in animals given cisplatin compared with those in control animals. CONCLUSION Obvious damage on hearing, liver and kidney of mice could be induced after consecutively 5 days administration of cisplatin with doses range from 3 0 to 4 0 mg?kg -1 (body weight). Oxidative damage is one of the mechanisms of these toxic effects on liver and kidney induced by cisplatin. But for different organs or at different stages of cisplatin administration, the main mechanism may be different.

The purpose of the study was to observe the effect of rapamycin (RAPA) on the differentiation and maturation of rat bone marrow-derived dendritic cells (BMDCs) in vitro. BMDCs from Wistar rats were cultured with granulocyte-macrophage colony-stimulating factor plus interleukin-4 in the presence or absence of RAPA (20 ng/mL), and stimulated with lipopolysaccharide (LPS) for 24 h before cells and supernatants were collected. Surface phenotype of BMDCs was flow-cytometrically detected to determine the expression of maturation markers, MHC class II and CD86. Supernatants were analyzed for the production of IL-12 and IFN-gamma cytokines by using ELISA. BMDCs were co-cultured with T cells from Lewis rats and mixed lymphocyte reaction was assessed by MTT method. The morphology of BMDCs stimulated with LPS remained immature after RAPA pretreatment. RAPA significantly decreased the CD86 expression, impaired the IL-12 and IFN-gamma production of BMDCs stimulated with LPS, and inhibited the proliferation of allogeneic T cells. In conclusion, RAPA can inhibit the maturation of BMDCs stimulated with LPS in terms of the morphology, surface phenotype, cytokine production, and ability of BMDCs to stimulate the proliferation of allogeneic T cells in vitro.

OBJECTIVETo investigate the effect of lead-exposed astrocyte conditioned medium (ACM) on the synaptic formation of neurons and to provide reference for the mechanism of lead neurotoxicity.

METHODSAstrocytes were cultured in the medium containing 50, 100, 200, 400, and 800 µmol/L lead acetate for 72 h. Alamar Blue was used to assess the cell viability of astrocytes, and then ACM was collected. Primarily cultured neurons were divided into six groups: pure culture group, non-glutamic acid (Glu)-induced ACM treatment group, Glu-induced lead-free ACM treatment group, and Glu-induced 50, 100, and 200 µmol/L lead acetate-exposed ACM treatment groups. Neurons were collected after being cultured in ACM for 24, 48, or 72 h. The content of synaptophysin (SYP) in neurons was determined by Western blot. The SYP expression in neurons was measured by immunofluorescence after being cultured in ACMfor 72 h.

RESULTSIn all lead-exposed groups, the cell viability of astrocytes declined with increasing concentration of lead (P < 0.05). The Western blot showed that compared with the pure culture group, the non-Glu-induced ACM treatment group and Glu-induced lead- free ACM treatment group had significantly increased content of SYP in neurons (P < 0.01); compared with the non-Glu-induced ACM treatment group, the Glu-induced ACM treatment groups had significantly reduced SYP expression in neurons (P < 0.05); compared with the Glu-induced lead-free ACM treatment group, all lead-exposed ACM treatment groups had the content of SYP in neurons significantly reduced with increasing concentration of lead after 72-h culture (P < 0.01), the 200 µmol/L lead-exposed ACM treatment group had significantly reduced content of SYP in neurons after 48-h culture (P < 0.01), and all lead-exposed ACM treatment groups showed no significant changes in the content of SYP in neurons after 24-h culture. Double-labeling immunofluorescence of SYP showed that all lead-exposed ACM treatment groups had a significant decrease in the number of SYP-fluorescent particles after 72-h culture (P < 0.05).

CONCLUSIONAstrocytes promote synaptic formation of neurons, which may be inhibited during lead exposure.

Astrocytes ; drug effects ; physiology ; Cell Survival ; drug effects ; Cells, Cultured ; Culture Media, Conditioned ; metabolism ; Glutamic Acid ; metabolism ; Lead ; toxicity ; Neurons ; drug effects ; Synapses ; drug effects ; physiology

The purpose of the study was to observe the effect of rapamycin (RAPA) on the differentiation and maturation of rat bone marrow-derived dendritic cells (BMDCs) in vitro. BMDCs from Wistar rats were cultured with granulocyte-macrophage colony-stimulating factor plus interleukin-4in the presence or absence of RAPA (20 ng/mL), and stimulated with lipopolysaccharide (LPS) for 24h before cells and supernatants were collected. Surface phenotype of BMDCs was flow-cytometrically detected to determine the expression of maturation markers, MHC class Ⅱ and CD86. Supematants were analyzed for the production of IL-12 and IFN-γ cytokines by using ELISA.BMDCs were co-cultured with T cells from Lewis rats and mixed lymphocyte reaction was assessed by MTT method. The morphology of BMDCs stimulated with LPS remained immature after RAPA pretreatment. RAPA significantly decreased the CD86 expression, impaired the IL-12 and IFN-γproduction of BMDCs stimulated with LPS, and inhibited the proliferation of allogeneic T cells. In conclusion, RAPA can inhibit the maturation of BMDCs stimulated with LPS in terms of the morphology, surface phenotype, cytokine production, and ability of BMDCs to stimulate the proliferation of allogeneic T cells in vitro.