1.Fabrication and evaluation of hydroxyapatite-chitosan scaffold via simulated body fluid biomimetic mineralization.
Ke XU ; Yanhong ZHAO ; Hongfa LI
West China Journal of Stomatology 2016;34(1):6-11
OBJECTIVEThis research aimed to fabricate a hydroxyapatite (HA)-chitosan scaffold via simulated body fluid (SBF) biomimetic mineralization and determine how mineralization time affects scaffold construction and cell compatibility.
METHODSThe HA-chitosan scaffolds were fabricated by freeze-drying technique and then subjected to precalcification, also known as alternative soaking method. Afterward, precalcificated scaffolds were placed into the SBF to conduct the mineralization process. Mineralization time was set at 7, 14, and 21 days, corresponding to three experimental groups. Pure chitosan scaffolds acted as the control group, and the physical and chemical properties of the four groups were tested. Osteogenic-induced adipose-derived stem cells (ADSCs) were seeded into the scaffolds to investigate the scaffolds' cell compatibility.
RESULTSThe mineral substance of the 14-day group exhibited a uniform distribution. The crystal composition of the mineral substance suited the HA's features. The compressive elastic modulus increased along with the extension of mineralization time. The 21-day group showed a statistically significant increase in compressive elastic modulus compared with the control group (P < 0.05). The cell proliferation level of the 14-day group was significantly the highest among the three experimental groups (P < 0.05). The calcium ion and the type I collagen had the highest secretion amount when the cells were seeded into the 14-day group.
CONCLUSIONThe SBF biomimetic mineralization method can be used to fabricate HA-chitosan bone-tissue-engineering scaffolds. The biological compatibility, as well as the chemical and physical properties, reached the optimum levels at day 14.
Biomimetics ; Body Fluids ; Bone and Bones ; Cell Proliferation ; Chitosan ; Collagen Type I ; Durapatite ; Osteogenesis ; Tissue Scaffolds
3.Selection of shade-matching in dental practice of Shenzhen area
Yu PAN ; Xiangxia LI ; Ke ZHAO
Chinese Journal of Medical Aesthetics and Cosmetology 2011;17(5):362-364
Objective To survey the shade-matching practice in Shenzhen city so as to strengthen communication between dentists and dental technicians,and to improve the successful rate of shadematching in prosthetic dentistry.Methods Questionnaire surveys were conducted in 251 dentists in some dentistry institutions of Shenzhen during the period from Aug 1st,2008 to Aug 27th,2010,including shade-guide selection,shade-matching technique and communication between dentists and technicians.Questionnaires were collected and statistically analyzed.Results From the analyzed ques tionnaires on shade-taking of 202 dentists,38.6 % of dentists evaluated color of restorations with Vitapan 31-Master shade guides; 17.7 % preferred Vitapan Classical shade guides,while 41.4 % used both.55.9 % dentists performed shade-matching in an inappropriate way with Vitapan 3D-Master shade guides.41.6 % of them never or rarely cornmunicated with dental technicians about color matc hing problems.Conclusions Shade guides are commonly and widely used by dentists in Shenzhen area.However,and few attentions are paid to a correct way of shade-matching and communications with dental technicians,which might be one of the main causes responsible for color mismatch.
4.Histomorphology,cellular biocompatibility and tensile force resistance property of fibrin-binding amniotic membrane in vitro
Journal of Third Military Medical University 1983;0(04):-
Objective To investigate the histomorphology,cellular biocompatibility in vitro and tensile force resistance property of fibrin-binding amniotic membrane(FBAM)and to explore its feasibility and superiority using as ocular surface graft.Methods After observing the morphology of FBAM under light microscope and scanning electron microscope,we did primary culture of corneal epithelial cells,taking monolayer fibrin-binding amniotic membrane as carrier,then observed cell growth overlay area.The elongation nature of FBAM was tested on electronic universal testing machine by calculating elastic modulus,using bilayer amniotic membrane(BAM)and monolayer amniotic membrane(MAM)as controls.Results The fresh FBAM was integrated as a whole,with structurally complete fibrin and amniotic membrane as well as tight binding of fibrin to amniotic membrane.The reserved FBAM was structurally complete,brittler than the fresh FBAM,while amniotic membrane still bound tightly to the fibrin,but under microscope the fiber reticular formation was fairly fuzzy.Single layer of epithelial cells was formed on FBAM after about seven-day culture in vitro.Disparity of cell growth overlay area was significant(P
5.Study on the clinical features of patients with aplastic anemia-paroxysmal nocturnal hemoglobinuria syndrome and typical paroxysmal nocturnal hemoglobinuria.
Mingfeng ZHAO ; Zonghong SHAO ; Ke LI
Chinese Journal of Practical Internal Medicine 2001;0(03):-
Objective To explore the differences of clinical features and relationship between aplastic anemia paroxysmal nocturnal hemoglobinuria syndrome(AA PNH syndrome)and typical paroxysmal nocturnal hemoglobinuria(t PNH).Methods A case control study on the discrepancies of clinical and laboratory features between patients with AA PNH syndrome and t PNH was carried out.Results Compared with t PNH,AA PNH syndrome showed following features:①Lower frequencies of venous thrombosis,jaundice and enlarged liver or spleen.②Higher percentages of pancytopenia and bone marrow hypoplasia.③Lower percentages of positive hemolysis tests.The percentages of CD55 and CD59 of peripheral blood cells were not significantly different in most cases of both groups.④Immunoglobulins and subgroups of T lymphocytes were normal in cases of both groups.⑤Adrenocortical hormone was effective in cases of both groups.Conclusion AA PNH syndrome shares a same pathophysiology with t PNH;CD55 and CD59 tests can improve the diagnosis of AA PNH syndrome.
6.Recent research progress on platelet apoptosis.
Li-li ZHAO ; Chang-geng RUAN ; Ke-sheng DAI
Chinese Journal of Hematology 2012;33(8):687-689
7.In vitro blockade of SDF-1/CXCR4 signaling pathway by T140 to prevent degradation of type Ⅱ collagen in human articular cartilage
Ke MA ; Xiaolin LI ; Yanlin LI ; Xiaosong ZHU ; Fengkai ZHAO
The Journal of Practical Medicine 2014;(12):1879-1882
Objective To explore the impact of blockade of SDF-1/CXCR4 signaling pathway by T140 on degradation of typeⅡ collagen in human articular cartilage and to define the mechanism of action of T140. Methods 144 pieces of cartilage (Mankin score of 0 or 1) were obtained from osteoarthritis patients undergoing total knee replacement ( OA cartilage group) and 144 pieces of cartilage (Mankin score of 0 or 1) were obtained from patients receiving traumatic amputation (normal cartilage group). Each group was treated with SDF-1 of 100 ng/mL, then divided into three subgroups A, B, and C. The cartilage tissue in each group was cultured in the nutrient solution containing of T140, MAB310, or SDF-1 (1 000 nmol/L) for 48 or 96 hours. RT-PCR was used to detect expression of typeⅡcollagen mRNA in the cartilage tissue. Results Level of type Ⅱcollagen mRNA was markedly higher in subgroup A than in subgroup B and subgroup C at the same group and the same time (P <0.05). The expression level of type Ⅱcollagen mRNA at the same time and in the same subgroup of OA cartilage group were lower than that in normal cartilage group (P < 0.05). Conclusions SDF-1 induces degradation of typeⅡcollagen in human articular cartilage thruogh the SDF-1/CXCR4 signaling pathway. T140 can block the SDF-1/CXCR4 signaling pathway and reduce the degradation of type II collagen.
8.Modulatory effect of Evodiamine on JAK2/STAT3 signal pathway in HCT-116 cells
Lyucui ZHAO ; Ke LIAO ; Keqiong LI ; Jing LI
Chinese Pharmacological Bulletin 2015;(10):1394-1397,1398
Aim To investigate the inhibitory effect of Evodiamine on JAK2/STAT3 signal pathway in human colorectal cancer cell line HCT-116 . Methods Cells were cultured with 6. 0 μmol·L-1 Evodiamine for 2, 4 and 6 h, respectively. Cell nuclear morphology was detected by Hoechst staining and protein expression levels of JAK2 , p-JAK2 , STAT3 and p-STAT3 were examined by Western blot. Cells were treated with dif-ferent concentrations of AG490 for 48 h to select proper working concentration and cells treated with 6 μmol · L-1 EVO and 50 μmol · L-1 AG490 to compare the modulatory effect of EVO with AG490 on JAK2/STAT3 signal pathway. Results Hoechst staining revealed that Evodiamine could induce cells apoptosis, chroma-tin condensation gathered and typical apoptotic mor-phological changes in a time-dependent manner;West-ern Blot suggested that EVO could inhibit p-STAT3 significantly. After treatment with AG490, JAK2/STAT3 signal pathway was inactivated, the inhibitory effect of EVO on p-STAT3 was stronger than that of AG490 , while EVO combined with AG490 could fur-ther inhibit the expression of p-STAT3 significantly. Conclusions The anticancer effect of Evodiamine is mainly mediated by the modulation of JAK2/STAT3 signal pathway in HCT-116 cells.
9.ANALYSIS OF L-VALINE BIOSYNTHESIS MECHANISM BY METABOLIC FLUX BALANCE MODEL
Ke-Xu ZHANG ; Li-Li ZHAO ; Bei ZHANG ; Ning CHEN ;
Microbiology 1992;0(05):-
Using metabolic flux balance model , the metabolic flux balance of L- v aline synthesis was established in this paper by material balances and linear p rogramming method. The analysis results indicate that 62.8% metabolic flux ent er ed EMP pathway and 38.2% metabolic flux entered the HMP pathway. And only 9.2 % c arbon entered the TCA cycle. But comparing to the optimal flux distributions of 92.31, the production of L-valine should be improved from the genetic manipula ti on and fermentation control through reducing byproduct of amino acid and decreas ing the metabolic flux.
10.Effect and mechanisms of combined immunosuppressive agents sequential therapy in murine models of chronic graft-versus-host disease
Hua WEI ; Ke XU ; Guanghui HOU ; Wenpeng ZHAO ; Xiaofeng LI
Chinese Journal of Rheumatology 2011;15(11):777-782
ObjectiveTo explore the effects and possible mechanisms of VCR combined with low dose cyclophosphamide(CTX) intermittently to treat severe systemic lupus erythematosus(SLE).It is assumed that this might be a new combination therapy for SLE and expected to improve the overall prognosis and outcome of SLE.MethodsMurine chronic graft-versus-host disease(cGVHD) model were developed for study.They were randomly divided into the control group,vincristine (VCR) pulse therapy group,CTX pulse therapy group,CTX every other day(EOD) group,VCR+CTX combination group.One way ANOVA and repeated measure variance analysis were used for statistical analysis.Results① Six weeks after cGVHD models were set up,the average 24-hour urine protein quantification was(5.02±0.88) mg,anti-dsDNA antibody was positive,and Ⅳ LN pathology could be observed histologically in the model murine.So cGVHD models were successfully developed.② Significantly difference in decreasing of 24-hour urine protein quantification was found in the CTX EOD group,VCR+CTX combination group and other groups (P<0.01).Significant decrease in Cr,ALT,anti-dsDNA,was found in the CTX EOD group,VCR+CTX combination group,CTX pulse therapy group and other groups(P<0.05).Decrease in urine MCP-1 and TGF-β1 could be detected,and statistical significant difference in these parameters could be found in the CTX EOD group,CTX pulse therapy group,VCR+CTX combination group and other groups (P<0.01).MCP-1 and TGF-β1'expression in model kidney were reduced in the CTX EOD group,VCR+CTX combination group and had statistical significant difference in the CTX EOD group,VCR+CTX combination group,VCR pulse therapy group,and CTX pulse therapy group.③ VCRand CTX combination treatment was effectivein 24-hour urine protein quantification,blood Cr,ALT,anti-dsDNA and urine MCP-1,as well as urine TGF-β1 (P<0.05).Conclusion ① The combination of VCR and CTX is synergistic in decreasing 24-hour urine protein quantification,Cr,and the expression of MCP-1,TGF-β1.② The adverse effect of VCR+CTX combination group is similar to VCR pulse therapy group and CTX pulse therapy group.