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Quan R.,Xiaoshan Traditional Chinese Medical Hospital | Wang C.,Shanghai University | Wang H.,Shanghai University | Wei X.,Shanghai University | Zhao Z.,Shanghai University
Asian Journal of Chemistry | Year: 2013

Hydroxyapapite has been widely used because of its excellent biocompatibility. In this work, we studied the decomposition characteristics of both nano-hydroxyapapite powders prepared by the precipitation method and the corresponding sinters at the temperature from room temperature to 1500°C. X-Ray diffractometer, Raman spectroscopy and high temperature differential scanning calorimeter were employed to investigate the decomposition characteristics. Results show that hydroxyapapite powders gradually release the OH- ions from 1000°C and decompose into b-tricalcium phosphate (b-TCP) and tetracalcium phosphate (TTCP) when the heating temperature is higher than 1360°C and the b-TCP phase changes into a-TCP at about 1450°C, which remains if the sinter cools to the room temperature. We also found that the decomposed sinters can reconstitute to hydroxyapapite again under a slow cooling rate and in a certain atmosphere. This work revealed and compared the decomposition and regeneration characteristics of hydroxyapapite powders and sinters, which is useful for the applications of hydroxyapapite materials. Source


Quan R.,Xiaoshan Traditional Chinese Medical Hospital
Scandinavian journal of rheumatology | Year: 2013

To evaluate the effects of the proteasome inhibitor MG-132 on the expression of nuclear factor (NF)-κB p65, inhibitor (I)-κB, tumour necrosis factor (TNF)-α, and interleukin (IL)-1β in the cartilage and synovial tissues of rats with osteoarthritis (OA), and to investigate the role that the ubiquitin/proteasome system (UPS) plays in the OA process. A total of 144 adult male Sprague Dawley rats were randomly assigned to four groups: anterior cruciate ligament transaction (ACLT) + MG-132 (ACLT/M), ACLT + dimethylsulfoxide (ACLT/D), sham surgery (Sham), and naïve + MG-132 (naïve/M). Pathological morphology was undertaken. mRNA expression levels of NF-κB p65, I-κB, TNF-α, and IL-1β were determined using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The activities of the 20S proteasome chymotrypsin-like and peptidylglutamyl-peptide hydrolase-like enzymes were measured using fluorospectrophotometry. The Mankin scores at all time points in ACLT/M rats were significantly lower than those in ACLT/D rats (p < 0.05). Despite the NF-κB p65 in the synovial tissue at 2 weeks after surgery and IL-1β in the cartilage tissue at 12 weeks after surgery, mRNA expression levels of NF-κB p65, IL-1β, and TNF-α at other time points in ACLT/M were significantly lower than those in ACLT/D (p < 0.05). mRNA levels of I-κB in the cartilage tissue in ACLT/M were significantly higher than those in ACLT/D at 2 weeks after surgery (p < 0.05). mRNA levels of I-κB in the synovial tissue in ACLT/M were higher than those in ACLT/D at all time points, and the difference was significant at 4 weeks after surgery (p < 0.05). MG-132 decreased the activities of the 20S proteasome chymotrypsin-like and peptidylglutamyl-peptide hydrolase-like enzymes in the cartilage and synovial tissues of rats. The proteasome inhibitor MG-132 delays the progress of OA by alleviating synovial inflammation and protecting the articular cartilage tissue. Source


Wang C.-Y.,Shanghai University | Quan R.-F.,Xiaoshan Traditional Chinese Medical Hospital | Wang H.-B.,Shanghai University | Wei X.-C.,Shanghai University
Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of Technology | Year: 2010

X-ray diffractometer (XRD), high-temperature raman spectroscopy, high-temperature differential scanning calorimeter (DSC) were used to investigate their decomposition characteristics of both hydroxyapatite powder and sinters, also their regeneration characteristics were explored. Results showed that nano HA powder prepared by the precipitation method gradually released its OH-ions from 1000°C. When the heating temperature was higher than 1360°C, HA decomposed into β-tricalcium phosphate (β-TCP) and tetracalcium phosphate (TTCP). β-TCP changed into α-TCP at about 1450°C. It was found that the decomposed powder regenerate to HA again under a slow cooling rate and in air atmosphere, and yet no any regeneration phenomenon was found in the decomposed sinters. When the decomposed sinters which was sintered at 1500°C were heat treated at 900°C in CO2 and H2O atmosphere, the regeneration of HA was partly found on the surface of the sinters. There is high significance of investigating on the decomposition and regeneration characteristics of HA for its application. Source


Shao R.,Zhejiang Chinese Medical University | Quan R.,Xiaoshan Traditional Chinese Medical Hospital | Zhang L.,Zhejiang Chinese Medical University | Wei X.,Shanghai University | And 2 more authors.
Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan | Year: 2015

The goals of bone tissue engineering are to apply biomaterial scaffolds with adhered cells, such as osteoblasts, bone marrow stromal stem cells, or chondrocytes, to repair, regenerate, and restore the functions of damaged bone tissue or to replace those tissues with porous engineered biomaterials. Over recent decades, a diverse class of biomaterials has been applied in bone tissue engineering field. Porous hydroxyapatite bioceramic is currently receiving significant attention as a bone tissue engineering substitute because of its biological characteristics, including biocompatibility, bioactivity, osteoconduction, and vasculogenesis. This biomaterial has a three-dimensional structure with interconnected spherical pores of uniform size, which encourages bone ingrowth and achieves good integration of the material and the host bone over time. However, the compressive strength and elastic modulus of porous hydroxyapatite scaffolds generally weaken as the porosity increases, in both in vitro and in vivo testing. Zirconia can be used to toughen hydroxyapatite materials for bone repair and replacement because of its unique biomechanical properties, including compressive strength and fracture toughness. Additionally, a zirconia chitosan hybrid containing bone morphogenetic protein-2 and mesenchymal stem cells derived from induced pluripotent stem cells has been used as a coating material adhered to surface of scaffolds to promote bone regeneration and repair. Here, we provide a succinct review of zirconia toughened hydroxyapatite biomaterial scaffolds that incorporate bone morphogenetic protein-2 and mesenchymal stem cells for bone tissue engineering and describe the biomaterials that are currently being investigated based on the recent literature and our own data. © 2015 The Ceramic Society of Japan. Source


Quan R.,Xiaoshan Traditional Chinese Medical Hospital | Tang Y.,Xiaoshan Traditional Chinese Medical Hospital | Huang Z.,Xiaoshan Traditional Chinese Medical Hospital | Xu J.,Xiaoshan Traditional Chinese Medical Hospital | And 2 more authors.
Ceramics International | Year: 2012

To evaluate the effects of hydroxyapatite/Zirconiumoxide (HA/ZrO 2) composite powder on proliferation and osteogenic differentiation of rabbit mesenchymal stem cells (MSCs) by using molecular biology methods in vitro. HA/ZrO 2 composite powder prepared by using powder of HA and ZrO 2 with different proportions sintered at 1600 °C were compared with pure HA powder and pure ZrO 2 powder. The effects of the composite powder suspensions on the proliferation of the rabbit MSCs were measured by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay), alkaline phosphatase (ALP) activities were measured by the ALP colorimetric assay, and the cellular expression levels of Collagen I, osteocalcin and osteopontin mRNAs were determined by Reverse Transcription Polymerase Chain Reaction (RT-PCR). The HA phase was transformed into the β-Ca 3(PO 4) 2(β-TCP), α-Ca 3(PO 4) 2 and CaZrO 3 phases in the composite powder after sintering at 1600 °C, with a positive correlation between the contents of the HA phase and the new phases. The MTT assay showed that both pure HA powder and HA containing composite powder were able to promote cellular proliferation, but pure ZrO 2 powder had no effect in stimulating cell proliferation (P<0.05). Vonkossa staining revealed that the composites and pure HA powder were capable of reducing the percentages of positively stained cells. The ALP colorimetric assay demonstrated that the ALP activities of cells maintained in culture media with HA and HA containing composite powder were significantly higher than that of cells cultured in regular media or media containing pure ZrO 2 (P<0.05). RT-PCR results showed that the composite powder were able to stimulate the expression of Collagen I and osteocalcin. The HA/ZrO 2 composite powder can also facilitate osteogenic differentiation. © 2012 Elsevier Ltd and Techna Group S.r.l. Source

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