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Objective: To investigate causes and factors affecting microcalcification (MC) changes after neoadjuvant chemotherapy (NAC) in patients with breast cancer and to assess the correlation between MC reduction and complete remission rate [pathological complete response (pCR)] of tumors. Methods: Clinical data of 215 patients with breast cancer who visited Tianjin Medical University Cancer Hospital from January 1, 2015 to December 31, 2018 were collected. The patients were grouped according to MC range and number of changes, and factors that affected MC changes were evaluated. According to whether MC decreased or not, the patient group was divided into the MC range and MC number reduction groups, and the correlation between the decrease in MC and pCR, assessed using different molecular typing methods, was analyzed . The sensitivity and specificity of the receiver operating characteristic curve analysis (ROC) were used to evaluate the accuracy of MC reduction in predicting pCR. Results: The patients with a distribution of diffuse, initial MC range of >2 cm and MC quantity of >20 were more likely to have an MC reduction. The pCR rate was higher in the group with reduced and non-reduced MC. No significant difference was found between the group with decreased MC and the control group. The decreases in MC according to the different molecular typing methods were independent of factors affecting pCR. Reduction in MC range predicts pCR with a sensitivity of 77.78 and specificity of 57.45 (P=0.0001). Conclusions: The change factors of MC in patients with breast cancer after neoadjuvant chemotherapy were the range, number, and distribution of calcification. The pCR rate of the patients with reduced MC was high, but the accuracy of pCR prediction based on reduced MG was low. Thus, mammography was not recommended for evaluating pCR after neoadjuvant chemotherapy.
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Objective@#To sample survey the relationship between acute mountain sickness and mental health of officers and soldiers, so as to provide theoretical direction for the psychological prevent and counsel of them.@*Methods@#In May 2017, 61 officers and soldiers were selectedas subject investigated, and divided to AMS group included 35 persons and non-AMS group included 26 persons according to the finding of theAMS symptom division point table, then used symptom self-testing tableto test and evaluate the mental health of them.@*Results@#The AMS group showed significantly higher scores on the psychological parameters such as omatization, interpersonal sensitivity, depression, anxiety, phobicanxiety, parnoid ideation and so on (105.20±13.82, 1.37±0.26, 1.14±0.21, 1.16±0.19, 1.16±0.18, 1.06±0.11, 1.10±0.17, 1.22±0.19, P<0.05) .@*Conclusion@#The mental factors of omatization, interpersonal sensitivity, depression, anxiety, phobic anxiety, parnoid ideation and so on had great influence on AMS, we should pay attention to these factors and carry on mental intervention, and enhance anti-stress ability of individual, to ensure the successful completion of plateau military mission.
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OBJECTIVE: To explore the effect of zinc oxide nanoparticles(ZnO NPs) on the oxidative damage in human alveolar type Ⅱ epithelial cell line A549.METHODS: The A549 cells in logarithmic growth phase were incubated with ZnO NPs solution at dose of 0,10,20 and 40 mg/L as 4 dose groups.The levels of reactive oxygen species(ROS) were measured by flow cytometer after 4 hours of exposure.The malondialdehyde(MDA) content and super oxide dismutase(SOD) activity were measured by microplate reader after 8 hours of exposure.RESULTS: The ROS levels in A549 cells exposed to 10,20,40 mg/L ZnO NPs were significantly increased compared with control group(P<0.05).The level of ROS increased with the exposure dose of ZnO NPs in A549 cells(P<0.01).The activities of SOD in A549 cells exposed to 10,20,40 mg/L ZnO NPs were significantly decreased compared with control group(P<0.05).The level of MDA and the ratios of MDA/SOD increased compared with control group(P<0.05).The activity of SOD in A549 cells decreased with the increase of ZnO NPs exposure dose(P<0.01),and the level of MDA and the ratios of MDA/SOD increased with the increase of exposure(P<0.01).CONCLUSION: ZnO NPs could induce lipid peroxidation in A549 cells with a dose-effect relationship.
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Objective:To study the effects of miR-20a on the osteogenic differentiation potential of inflammatory periodontal liga-ment cells(IPDLSCs).Methods:Cells were isolated and cultured from the healthy and inflammatory periodontal ligament samples (HPDLSCs and IPDLSCs)respectively.miR-20a expression was analyzed by qRT-PCR.Alizarin red staining,Western blot and PCR were used to evaluate the osteogenic differentiation potential of IPDLSCs after transient transinfection of miR-20a mimics or inhib-itor.Results:miR-20a expression in IPDLSCs was lower than that in HPDLSCs,and the osteogenic differentiation potential of IP-DLSCs were promoted by miR-20a mimics,and reduced by miR-20a inhibitor.Conclusion:The miR-20a in IPDLSCs was down reg-ulated.miR-20a can promote the osteogenic differentiation potential of IPDLSCs.
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On page 219, there was an error in the Fig. 5.
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PURPOSE: To measure the surface loss of dental restorative zirconia and the short-term bond strength between an indirect composite resin (ICR) and zirconia ceramic after various sandblasting processes. MATERIALS AND METHODS: Three hundred zirconia bars were randomly divided into 25 groups according to the type of sandblasting performed with pressures of 0.1, 0.2, 0.4 and 0.6 MPa, sandblasting times of 7, 14 and 21 seconds, and alumina powder sizes of 50 and 110 microm. The control group did not receive sandblasting. The volume loss and height loss on zirconia surface after sandblasting and the shear bond strength (SBS) between the sandblasted zirconia and ICR after 24-h immersion were measured for each group using multivariate analysis of variance (ANOVA) and Least Significance Difference (LSD) test (alpha=.05). After sandblasting, the failure modes of the ICR/zirconia surfaces were observed using scanning electron microscopy. RESULTS: The volume loss and height loss were increased with higher sandblasting pressure and longer sandblasting treatment, but they decreased with larger powder size. SBS was significantly increased by increasing the sandblasting time from 7 seconds to 14 seconds and from 14 seconds to 21 seconds, as well as increasing the size of alumina powder from 50 microm to 110 microm. SBS was significantly increased from 0.1 MPa to 0.2 MPa according to the size of alumina powder. However, the SBSs were not significantly different with the sandblasting pressure of 0.2, 0.4 and 0.6 MPa. The possibilities of the combination of both adhesive failure and cohesive failure within the ICR were higher with the increases in bonding strength. CONCLUSION: Based on the findings of this study, sandblasting with alumina particles at 0.2 MPa, 21 seconds and the powder size of 110 microm is recommended for dental applications to improve the bonding between zirconia core and ICR.
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Adhesives , Aluminum Oxide , Ceramics , Immersion , Microscopy, Electron, Scanning , Multivariate AnalysisABSTRACT
Objective To investigate the influence of FOXP 3 expression in pancreatic carcinoma cells (PCCs) on the maturation and immunologic function of dendritic cells (DCs).Methods The siRNA sequences targeting FOXP3 gene (siRNA-FOXP3) and negative control siRNA (siRNA-NC) were specifically designed and transfected into PCCs , then the level of IL-10 and TGF-β1 of culture supernatant were detected by ELISA.The supernatants of pancreatic carcinoma cell transfected by FOXP 3-siRNA were collected , then it was mixed with GM-CSF and IL-4 to induce the differentiation of DCs .Flow cytometric analysis were used to measure the expression of surface markers CD 86 , CD80 , HLA DR on DCs which were treated with supernatants . The levels of IL-12p70, IFN-γin supernatants were detected by ELISA .The DCs were co-cultured with T lymphocytes, and then the lymphocytes proliferation and cytoxicity were analyzed by CCK -8 assays.Results Compared with PANC1 with siRNA-NC transfection, PANC1 with siRNA-FOXP3 transfection had a decreased expression of IL-10, TGF-β1 [(8.93 ±3.06)ng/L vs (26.60 ±5.57)ng/L;(2 544 ±78)ng/L vs (2 856 ± 92)ng/L], the positive expression rate of CD86, HLA DR in DCs cultured in the medium containing the supernatants of the pancreatic carcinoma cell transfected by siRNA-FOXP3 was significantly increased [(28.10 ±3.11)%vs (13.90 ±0.42)%;(66.15 ±4.17)%vs (43.15 ±3.32)%], the expression of IL-12p70, IFN-γwas significantly increased [(52.75 ±7.89)ng/L vs (26.14 ±4.50)ng/L, (898.43 ±88.82) ng/L vs (412.76 ±24.68) ng/L], after co-culture with lymphocytes at ratios of 1:5, 1:10, 1:20, the proliferation was significantly increased [(95.27 ±3.80)% vs (71.77 ±5.70)%, (78.97 ±5.73)% vs (52.30 ±8.72)%, (57.60 ±4.36)% vs (43.73 ±6.01)%], and the cytoxicity of CTL to PANC1 cells with 1:20, 1:40 co-culture was significantly increased [(28.44 ±5.20)% vs (8.82 ±2.29)%, (40.85 ± 5.15)% vs (17.38 ±4.86)%], and the difference between the two groups was statistically significant (P<0.05).Conclusions FOXP3 expression in PCCs can inhibit the maturation and immunologic function of DCs.
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<p><b>OBJECTIVE</b>To explore the protein expression of heme oxygenase-1 (HO-1) and platelet endothelial cell adhesion molecules-1 (PECAM-1) in human coronary artery endothelial cells induced with Zinc Oxide Nanoparticle (ZnO-NPs).</p><p><b>METHODS</b>MTT assay was used to determine the cell viability of ZnO-NPs. Levels of HO-1 and PECAM-1 protein in culture supernatants were measured using ELISA after human coronary artery endothelial cells were treated with different concentrations (0, 10, 20, 40µg/ml) of ZnO-NPs for 24 h.</p><p><b>RESULTS</b>The cell viability of human coronary artery endothelial cells in each group was 89.76%, 83.61%, 63.10%, 53.20%, 48.11%, 42.35%, 38.06%, 25.44% respectively when treated with different concentrations of ZnO-NPs (12.5, 25, 50, 70, 80, 90, 100, 200µg/ml). Protein levels of HO-1 (ng/L) in each group were 0.041±0.011, 0.512±0.076, 0.906±0.059, 1.062±0.089 respectively after the stimulation of different concentrations of ZnO-NPs (0, 10, 20, 40µg/ml). Comparisons in each group were statistically significant (P < 0.05). Protein levels of PECAM-1 (µg/L) in each group were 7.966 ± 0.046, 7.993 ± 0.036, 8.629 ± 0.052, 8.811 ± 0.039 respectively after the stimulation of different concentrations of ZnO-NPs (0, 10, 20, 40 µg/ml). Compared with the control group, protein levels of PECAM-1 increased (P < 0.05) when the concentration of ZnO-NPs was 20µg/ml or 40 µg/ml.</p><p><b>CONCLUSION</b>ZnO-NPs stimulation could inhibit the viability of human coronary artery endothelial cells and upregulate the protein expression of HO-1 and PECAM-1.</p>
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Humans , Blood Platelets , Cell Survival , Coronary Vessels , Endothelial Cells , Heme Oxygenase-1 , Metabolism , Nanoparticles , Toxicity , Platelet Endothelial Cell Adhesion Molecule-1 , Metabolism , Zinc Oxide , ToxicityABSTRACT
PurposeIt is well known hypobaric hypoxia occurs with acute exposure to high altitude, with commonly associated change of cerebral blood flow (CBF). In this work, three-dimensional arterial spin-labeling (3D ASL) was used to monitor the change of CBF to further extend our understanding of hypobaric hypoxia.Materials and Methods Six healthy subjects were recruited for this study, they were asked to stay at high altitude areas for 5 days, and then returned to the plain. All subjects received MRI examination in both plain and high altitude areas using exactly the same 3.0T MR scanner. A total of 8 MR scans were performed, and all the parameters were kept the same, the changes of cerebral blood flow were observed.ResultsCBF increased obviously and reached its peak after acute exposure to high altitude, at the first day at high altitude, CBF measurements in global brain, grey matter and white matter increased signiifcantly compared to the plain, the difference was statistically significant (P<0.05); after that, the CBF measurements started to gradually decrease in the second day and a small climb on the third day at high altitude, then the CBF continued to drop after returning to sea level, even below that at sea level prior to departure. After 1 week back to the plain area, CBF measurements in global brain, grey matter and white matter were still lower than those before departure for high altitude areas, with a statistically signiifcant difference (P<0.05).ConclusionCBF measurements had obvious increase upon initial arrival at high altitude, and then the CBF continued to drop even below that at sea level prior to departure.
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The objective of this research is to evaluate the effects of different silane coupling agents on the bond strength between Ceramco3 opaque porcelain and indirect composite resin. Five groups of Co-Cr metal alloy substrates were fabricated according to manufacturer's instruction. The surface of metal alloy with a layer of dental opaque porcelain was heated by fire. After the surface of opaque porcelain was etched, five different surface treatments, i.e. RelyX Ceramic Primer (RCP), Porcelain Bond Activator and SE Bond Primer (mixed with a proportion of 1:1) (PBA), Shofu Porcelain Primer (SPP), SE bond primer (SEP), and no primer treatment (as a control group), were used to combine P60 and opaque porcelain along with resin cement. Shear bond strength of specimens was tested in a universal testing machine. The failure modes of specimens in all groups were observed and classified into four types. Selected specimens were subjected to scanning electron microscope and energy disperse spectroscopy to reveal the relief of the fracture surface and to confirm the failure mode of different types. The experimental results showed that the values of the tested items in all the tested groups were higher than that in the control group. Group PBA exhibited the highest value [(37.52 +/- 2.14) MPa] and this suggested a fact that all of the specimens in group PBA revealed combined failures (failure occurred in metal-porcelain combined surface and within opaque porcelain). Group SPP and RCP showed higher values than SEP (P < 0.05) and most specimens of SPP and RCP performed combined failures (failure occurred in bond surface and within opaque porcelain or composite resin) while all the specimens in group SEP and control group revealed adhesive failures. Conclusions could be drawn that silane coupling agents could reinforce the bond strength of dental composite resin to metal-opaque porcelain substrate. The bond strength between dental composite resin and dental opaque porcelain could meet the clinical requirements.
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Humans , Acrylic Resins , Chemistry , Ceramics , Chemistry , Composite Resins , Chemistry , Dental Bonding , Dental Porcelain , Chemistry , Polyurethanes , Chemistry , Resin Cements , Chemistry , Silanes , ChemistryABSTRACT
Objective To evaluate in vitro anti tumor effect of host lymphocyte primed by CalmetteGuerin bacillus (CGB) activated dendritic cells (DC) based PANC1 lysate. Methods DCs were obtained from peripheral blood mononuclear cells of healthy volunteer and cuitured by rhGM CSF and rhIL 4. DC vaccines for pancreatic cancer were loaded with PANC1 tumor lysate (TL) and were further maturated by CGB.CD1a, CD83, CD86 and HLA-DR phenotype was characterized by flow cytometer, and IL-12p70 and TNF-α concentration in DC culture supernatant were measured by ELISA. Autologous mixed lymphocyte proliferation and the cytotoxicity of cytotoxic T lymphocytes primed by activated DCs to PANC1, PaTu8988 and SCG7901 tumor cells was measured by CCK 8 test. Results When DCs based PANC1 lysate were activated by CGB,the expression rates of CD83 and CD86 were increased from (3.7±0.3)% and (38.6±5.0)% to (16.5±0.6)% and (76.6±2.5)% (P ＜0.05 ). The concentrations of cytokines ILpl2p70 and TNF-α were increased from (20.18±2.06 ) pg/mland (61.38±1.19) pg/mlto (62.48±3.80) pg/mland (592.53±17.96)pg/ml (P＜0. 01 ). When co-cultured with CGB activated DCs based PANC1 lysate in proportion of 0.40)% , (3.39±1.05)% , (2.82±0.39)% significantly increased to (55.38±3.58)% , (75.0±2.54) % , (77.07±3.4)% , (99.07±2.4)% (P＜0.01) , respectively. The killing effects of lymphocytes 2.77)%, (19.03±3.04) %; but the killing effects on PaTu8988 and SCG7901 were significantly decreased.Conclusions DC vaccines for pancreatic cancer could be more maturated when activated by CGB, and could show a high capability of anti-tumor in vitro.
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treated with heat shock and OK-432 demonstrated enhanced biological activities,and could induce host lymphocytes to highly effective and specific eytotoxieity against PANC1 cells.
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BACKGROUND: Orthodontic tooth movement is dependent on reconstruction of periodontium. Osteoclastic bone resorption is the first step of tooth movement. The present study hotspots focus on signal transduction pathway regarding osteoclast differentiation and functional development under stress and on the relationship between periodontal ligament cells and osteoclasts. OBJECTIVE: To set up a simple method to in vitro culture human osteoclast-like cells and to observe the effects of bone resorption-stimulating factors on differentiation, proliferation, and function of osteoclast-like cells, DESIGN, TIME AND STTING: A cytological in vitro controUod observation was performed at the Central Laboratory,Stomatology Hospital, Xi'an Jiaotong University between October 2007 and May 2008. MATERIALS: Umbilical cord blood was sourced from the healthy puerperae who had not suffered from high-risk pregnancy. Freshly prepared fetal femur provided by Laboratory Animal Center, Xi'an Jiaotong University and were used for preparation of bone flaps at 100-200 μm thickness. 1α ,25-(OH)2D3, macrophage colony-stimulating factor (M-CSF), prostaglandin E2 were purchased from Sigma Company, USA.METHODS: Under aseptic condition, umbilical cord blood was collected. Following Ficoll solution separation and centrifugation, supematant was discarded. Umbilical cord blood-derived mononuclear cells were suspended with o -modified minimal essential medium (α-MEM) solution and then inoculated into a 24-well culture plate, in which, coverslips and femoral slices were pre-placed, at a density of 1×109/L, 1.0 mL per well. Five groups were set, blank control, 108 mol/L 1α ,25-(OH)2D3, 10-7 mol/L 1α ,25-(OH)2D3, macrophage colony stimulating factor (M-CSF), and 1α ,25-(OH)2D3+prostaglandin E2 (PGE2). Each group was cultured for 7 days. MAIN OUTCOME MEASURES: Cellular growth morphology was observed under an inverted microscope; osteoclast-like celt formation was examined by tartrate-resistant acid phosphatase (TRAP) staining; and osteoclastic Howship's lacuna was detected by toluidine blue staining. Any cell with TRAP-positive staining and more than two nuclei was considered osteoclast-like cell and counted. RESULTS: After 3 days of culture, cells from the blank control group did not exhibit apparent changes in morphology and quantity. In the remaining groups, mononuclear cells appeared with confluent tendency. After 7 days of culture, a small number of osteoclast- like cells with 2-3 nuclei were found in the blank control group; a great many of multinucleated osteoclast- like cells with 3-20 nuclei were present in the remaining groups. Through the use of optical microscope, osteoclast-like cells could be found for the presence of red cytoplasm, bright yellow nuclei, and TRAP-positive staining in each inducing factor-treated group, in particular in the 108 mol/L 1α ,25-(OH)2D3 group, which displayed osteoclast- like cells exhibiting 14 nuclei, strong TRAP-positive staining, and a relatively big cell body. But no osteoclastic Howship's lacuna was found in any group. Compared to the blank control group, the numbers of osteoclast-like cells were greater in each inducing factor-treated group (F = 9.78, P < 0.01). There was no significant difference in the numbers of osteoclast-like cells between the 108 mol/L 1α ,25-(OH)2D3 and the 10-7 mol/L 1 a ,25-(OH)2D3 groups (P0.05). The M-CSF group and the 1α ,25-(OH)2D3+PGE2 group exhibited significantly less numbers of osteoclast-like cells than the 108 mol/L 1α ,25-(OH)2D3 group (F= 7.46, P< 0.01). CONCLUSION: After in vitro culture of 1α ,25-(OH)2D3, M-CSF, and PGE2, umbilical cord blood-derived mononuclear cells can differentiate into TRAP-positive multinucleated osteoclast-like cells, the 10-8 mol/L 1α ,25-(OH)2D3 being the most effective.
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Objective To investigate whether pantoprazole (PPZ), a proton pump inhibitor,could reverse the transmember pH gradient by inhibiting vacuolar H+-ATPase so as to increase the sensitivity of human gastric adenocarcinoma cell line SGC7901 to antitumor drugs and to evaluate the optimal time of drug administration, dosage of PPZ and the possible mechanism. Methods Western blotting and immunofluorescent staining were used to determine the expression and intracellular distribution of vacuolar H+-ATPase in human gastric adenocarcinoma cell line SGC7901 with or without PPZ pretreatment. 2', 7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein, acetoxymethyl ester (BCECF-AM) fluorescent probe was used to measure the intracellular pH value of human gastric adenocarcinoma cell line SGC7901 which pretreated with different dose and time of PPI. Methyl thiazolyl tetrazolium (MTT) assay and annexin V-fluorescent isothiocyanate-propidium iodide double staining were performed to evaluate the cytotoxic effects and apoptosis of cells treated with antitumor drugs combined with PPZ. Adriamycin (ADR) was used as probe to estimate drug accumulation and retention with PPZ pretreatment. Results After 24 hours, the expression of vacuolar H+-ATPase in cells pretreated with PPZ of 10 μg/ml (1.19±0.03) or 100 μg/ml (0. 70±0.03) was significantly lower than that in blank control (1.53±0. 05), but this expression was increased by pretreatment with PPZ of 1 μg/ml (2.29 +0.06, P<0.05). The inhibitory effects of PPZ (10 μg/ml) on vacuolar H+-ATPase was observed at 6 hours (0.32±0.02)and 12 hours (0. 13±0.02). And it could alter the intracellular distribution of vacuolar H+-ATPase at 24-hours. The intracellular pH value in cells pretreated with PPZ of 10 μg/ml (7.44±0. 09 ) or 100 μg/ml (7.31 ± 0. 06) was significantly decreased in comparison with untreated cells (7.51±0.05, P< 0. 01). After administration of anti-tumor drugs, the viability in SGC7901 cells pretreated with PPZ for 24 hours (58.71%±1.18 %) was significantly lower than that in cells untreated with PPZ (74. 33% ± 1.77%, P<0.05), while thetotal and early apoptotic rates in former cells(80.81% ±1. 16% and 77.52 %±1.13 %, respectively) were significantly higher than those in later cells (26. 42%±1.19% and 23. 18% ±0.92%,respectively,P < 0. 01). And the ADR releasing index in cells treated with PPZ (20, 50 and 100 μg/ml) for 24 hours was obviously lower than that in the blank control (0. 164±0. 013, 0. 162±0.015, 0. 152±0. 012 vs 0. 277±0. 011, respectively, P<0. 01). Conclusion The sensitivity of human gastric adenocarcinoma cell line to antitumor drugs may be increased by pretreatment with PPZ.
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Objective To evaluate endoscopic ultrasonography (EUS) in assessing endoscopic re-sectability of early esophagogastric cancer. Methods Data of 65 consecutive cases suspected as having early esophagogastric cancer with EUS and confirmed by pathology after endoscopic mucosal resection or endoscop-ic submucosal dissection within 2 weeks were retrospectively analyzed. The invasion depth of the lesion de-tected by EUS was compared with that from pathology. Results The accuracy of EUS in diagnosis of depth of early cancer invasion was 93.8% (61/65), and the overall accuracy in assessment of endoscopic resectabili-ty was 89. 2%. Conclusion Endoscopic resectability of early esophagogastric cancer can be accurately eval-uated with EUS.
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Objective To establish a stable and useful method for culturing human osteoclast-like cells in vitro,and investigate the effect of 1?,25-(OH)2D3,M-CSF and PGE2 on osteoclasts differentiation,proliferation and activation so as to lay the foundation for further study of the biological mechanism for tooth movement.Methods The HCMNC were isolated and cultured in 24-well plate with coverslips and human dentine slices.The experiment group was cultured with 1?,25-(OH)2D3,M-CSF and PGE2,respectively,while the control group was not.The liquid was changed every 3 days and the whole culture process lasted for 7 days.The phase contrast microscopy and TRAP staining were adopted to identify osteoclast-like cells.Results On the 3rd day the monocytes began to fuse and on the 7th day positive multinucleated cells could be seen with TRAP staining,but absorption pit was not formed on the dentin slices.The group with 1?,25-(OH)2D3 had the largest number of osteoclast-like cells.Conclusion After the monocytes in UCB are cultured by 1?,25-(OH)2D3,M-CSF,PGE2 induction,they can turn into TRAP(+) multinucleate osteoclast-like cells,the 1?,25-(OH)2D3 10-8mol/L being the most effective.
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Objective By culturing the osteoclasts together with the osteoblasts directly to investigate the effect of osteoblasts on the formation of mature osteoclasts.Methods The bone marrow mononuclear cells of rats were treated with 30?g/L M-CSF and 50?g/L RANKL and cultured for 6 days.Subsequently,the primary osteoblasts which were of the same quantity as the osteoclasts were co-cultured directly.In the co-culture system,we added the liquid containing 1,25-(OH)2D3 1?10-8mol/L and PGE2 1?10-6mol/L.The morphological observation,TRAP staining and pit staining were adopted to identify osteoclasts.Results When the osteoclasts were co-cultured with primary osteoblasts,the growth of osteoblasts had more preponderances.After staining,we could see more osteoblasts than osteoclasts.Conclusion The relationship between osteoblasts and osteoclasts is related to the relative quantities of the two cells.When osteoblasts outnumber osteoclasts,osteoblasts would inhibit the formation and differentiation of osteoclasts.