Objective To investigate the size effect of hydroxyapatite nanoparticles on proliferation and apoptosis of osteoblast-like cells.Methods Cetyltrimethylammnonium bromide (CTAB) was used to regulate the size of nano hydroxyapatite (nHAP) particles.All obtained particles were characterized by transmission electron microscopy (TEM),X-ray diffraction,dynamic light scattering and chemical analysis.HAP films were obtained by slowly coating cover glasses with 1% HAP particle suspension.MG-63 cells on three different films (20HAP,40HAP and 80HAP) were cocultured for up to 5 days.Cell proliferation assay was obtained by methyl thiazolyl tetrazolium (MTT).Cell apoptosis was detected by flow cytometric detection.Cell ultrastructure morphology was observed by TEM observation.Results nHAP with diameter of 20 nm,40 nm and 80 nm were synthesized and and analyzed.The MG-63 cells were cultured on three different fihns.The optical density value of cells on 20HAP was 1.22±0.13 after 5 days incubation,and there was no different compared to the control group (F=6.843,P=0.124).Cell number and viability were significantly higher on 20HAP compared to large nHAP after 5 days incubation.The percentage of apoptotic cells increased with increasiug nHAP particle size.TEM images showed 20HAP was found in cytoplasm and cell morphology had no changes.Conclusion Both cell proliferation and cell apoptosis are related to the size of the nHAP particles.20HAP was the most effective on promoting cell growth and inhibiting cell apoptosis.
Key words:
Hydroxyapatites; Nanoparticles; Osteoblasts
Postmenopausal osteoporosis is initiated by estrogen withdrawal and is characterized mainly by over-activated osteoclastic bone resorption. Targeting TNF receptor-associated factor 6 (TRAF6) or its downstream signaling pathways to modulate osteoclast formation and function is an appealing strategy for osteoclast-related disorders. In the present study, we determined the effect of tomatidine, a steroidal alkaloid derived from Solanaceae, on the formation and function of receptor activator of NF-κB (RANK) ligand-induced osteoclasts and the underlying mechanism. Tomatidine inhibited osteoclast formation in a dose-dependent manner and decreased the expression of osteoclast marker genes. Actin ring formation and osteoclastic bone resorption were attenuated in the presence of tomatidine in vitro. Eight weeks after ovariectomy, tomatidine prevented estrogen deficiency-induced bone loss and restored the mechanical properties of the femur. At the molecular level, tomatidine abrogated phosphorylation of c-Jun N-terminal kinase (JNK)/p38, NF-κB, and protein kinase B (Akt) pathway proteins by suppressing RANK expression, inhibiting the binding of TRAF6 to RANK, and downregulating the osteoclastogenesis marker-related protein expression. In summary, these data demonstrated that tomatidine attenuated osteoclast formation and function by modulating multiple TRAF6-mediated pathways. Therefore, tomatidine could be a novel candidate for the treatment of osteoclast-related disorders, including osteoporosis.—Hu, B., Sun, X., Yang, Y., Ying, Z., Meng, J., Zhou, C., Jiang, G., Li, S., Wu, F., Zhao, X., Zhu, H., Wu, H., Cai, X., Shi, Z., Yan, S. Tomatidine suppresses osteoclastogenesis and mitigates estrogen deficiency-induced bone mass loss by modulating TRAF6-mediated signaling. FASEB J. 33,2574–2586 (2019). www.fasebj.org
AIM: To observe the changes in heme oxygenase-1(HO-1) expression in the lung after ischmia-reperfusion of hind limbs in rats.METHODS: Hind limbs ischemia was made by clamping infrarenal aorta with a microvascular clip and lung injury was made by following reperfusion. Lung tissue was obtained from the animals subjected to sham operation, 4 h ischemia without reperfusion and 4 h, 8 h, 16 h, 24 h, 48 h reperfusion following 4 h ischemia. The levels of HO-1 mRNA and protein were measured at different times by Northern blot and Western blot. Immunohistochemistry technique was used to determine the cell types responsible for limb ischemic reperfusion induced HO-1 expression. RESULTS: After ischemia-reperfusion of limbs, HO-1 mRNA increased by 4 h, reached a peak at 16 h, and returned toward baseline at 24-48 h. This time course correlated with increased HO-1 protein. Immunohistochemical studies showed HO-1expressed in a variety of cell types, including the airway epithelium, alveolar macrophages and vascular smooth muscular cells. There were no positive signals in sham group and ischemia group both in mRNA levels and protein levels. CONCLUSION: The expression of HO-1 in the lung is not induced by limb ischemia or sham operation, but induced by limb reperfusion after ischemia in rats.
To investigate the relationship of T-2 toxin-induced chondrocytes apoptosis with nitric oxide(NO) and Fas apoptosis pathway.Human chondrocytes cultured in vitro were treated with different concentrations of T-2 toxin at different time (1-5 d). Cell viability of the treated cells was measured by MTT assay. Apoptotic ultrostructural changes of the treated cells were observed with electron microscopy. Biological changes of apoptosis were detected by annexin V/PI Flow cytometer (FCM). The levels of NO in culture media were detected by colorimetric method of Griess assay. Nitric oxide synthase (iNOS) and Fas protein were measured by Western blot.In this study the results shown the dose-dependent and time-dependent effects of T-2 toxin, within a range of concentration (1-2000 ng/mL) and a period of time (1-5 d), on the T-2 toxin-treated chondrocytes. Apoptotic body was found in T-2 toxin-treated chondrocytes by electron microscopy. Early-stage apoptosis rate and late-stage apoptosis rate were both increased in T-2 toxin-treated cells when compared with non-treated cells in a dose-dependent manner. The levels of NO in T-2 toxin-treated culture media were higher than that of normal control. Over-expressions of iNOS and Fas protein were detected in T-2 toxin-treated cells. T-2 toxin-induced apoptosis was noted to be significtnly correlated with the level of NO production and the levels of iNOS and Fas protein expression.T-2 toxin can enhance NO production and upregulate the expression of iNOS and Fas protein. Both NO and Fas signaling pathway are involved in T-2 toxin-induced apoptosis.
Background Steroids are a leading cause of femoral head osteonecrosis. Currently there are no medications available to prevent and/or treat steroid-associated osteonecrosis. Low-intensity pulsed ultrasound (LIPUS) was approved by the FDA for treating delayed union of bone fractures. Some studies have reported that LIPUS can enhance bone formation and local blood flow in an animal model of fracture healing. However, whether the effect of osteogenesis and neovascularization by LIPUS can enhance the repair progress in steroid-associated osteonecrosis is unknown. Questions/purposes We hypothesized that LIPUS may facilitate osteogenesis and neovascularization in the reparative processes of steroid-associated osteonecrosis. Using a rabbit animal model, we asked whether LIPUS affects (1) bone strength and trabecular architecture; (2) blood vessel number and diameter; and (3) BMP-2 and VEGF expression. Methods Bilateral femoral head necrosis was induced by lipopolysaccharide and methylprednisolone in 24 rabbits. The left femoral heads of rabbits received LIPUS therapy (200 mW/cm2) for 20 minutes daily and were classified as the LIPUS group. The right femoral heads of the same rabbits did not receive therapy and were classified as the control group. All rabbits were euthanized 12 weeks after LIPUS therapy. Micro-CT, biomechanical testing, histologic evaluation, immunohistochemistry, quantitative real-time PCR, and Western blot were used for examination of the effects of LIPUS. Results Twelve weeks after LIPUS treatment, the loading strength in the control group was 355 ± 38 N (95% CI, 315-394 N), which was lower (p = 0.028) than that in the LIPUS group (441 ± 78 N; 95% CI, 359-524 N). The bone tissue volume density (bone volume/total volume) in the LIPUS group (49.29% ± 12.37%; 95 % CI, 36.31%-62.27%) was higher (p = 0.022) than that in the control group (37.93% ± 8.37%; 95 % CI, 29.15%-46.72%). The percentage of empty osteocyte lacunae in the LIPUS group (17% ± 4%; 95% CI, 15%-20%) was lower (p = 0.002) than that in the control group (26% ± 9%; 95% CI, 21%-32%). The mineral apposition rate (μm/day) in the LIPUS group (2.3 ± 0.8 μm/day; 95% CI, 1.8 2.8 μm/day) was higher (p = 0.001) than that in the control group (1.6 ± 0.3 μm/day; 95% CL, 1.4-1.8 μm/day). The number of blood vessels in the LIPUS group (7.8 ± 3.6/mm2; 95% CI, 5.5-10.1 mm2) was greater (p = 0.025) than the number in the control group (5.7 ± 2.6/mm2; 95% CI, 4.0-7.3 mm2). Messenger RNA (mRNA) and protein expression of BMP-2 in the LIPUS group (75 ± 7, 95% CI, 70-79; and 30 ± 3, 95% CI, 28-31) were higher (both p < 0.001) than those in the control groups (46 ± 5, 95% CI, 43-49; and 15 ± 2, 95% CI, 14-16). However, there were no differences (p = 0.114 and 0.124) in mRNA and protein expression of vascular endothelial growth factor between the control (26 ± 3, 95% CI, 24-28; and 22 ± 6, 95% CI, 18-26) and LIPUS groups (28 ± 2, 95% CI, 26-29; and 23 ± 6, 95% CI, 19-27). Conclusions The results of this study indicate that LIPUS promotes osteogenesis and neovascularization, thus promoting bone repair in this steroid-associated osteonecrosis model. Clinical Relevance LIPUS may be a promising modality for the treatment of early-stage steroid-associated osteonecrosis. Further research, including clinical trials to determine whether LIPUS has a therapeutic effect on patients with early-onset steroid-associated osteonecrosis may be warranted.
Objective
To explore the application of descending step-down mode in safe transportation of patients after general anesthesia operation.
Methods
A total of 25 nurses in the Operation Room of the First People's Hospital of Ji'ning in Shandong Province were trained from January 2017 to June 2017. The nursing ability of nurses in operation room before and after training and the incidence of adverse events were compared.
Results
After the training, the score of the operation room nurse's theory examination, the emergency test score and the patient's transshipment ability were (85.26±4.96) , (86.77±4.77) and (88.98±5.02) , which were all higher than those before training (62.33±3.56) , (61.58±4.12) and (62.44±4.78) (P<0.05) . The transportation time after training was (9.52±1.85) min, which was shorter than that before training (15.21±3.40) min (P<0.05) . The incidences of adverse events such as the dropping or blocking of the infusion tube, the interruption of oxygen supply, the equipment failure and the fluctuation of the blood pressure of the patients after the training were 2.50%, 2.50%, 3.75% and 1.25%, which were all lower than before training (8.75%, 7.50%, 12.50%, 10.00%) (P<0.05) . The patient satisfaction after training (95.00%) was higher than that before training (80.00%) (P<0.05) .
Conclusions
The reduced step thinking mode can effectively improve the nursing skills of nurses in operation room and the safe transport ability of patients after general anesthesia, and reduce the occurrence of adverse events in the course of patients'transshipment after general anesthesia and improve the patient satisfaction.
Key words:
Operation room; General anesthesia operation; Safe transportation; Step-down thinking mode
Genistein, a nontoxic flavonoid compound, has potent antitumor activity in various cancer cells. In the present study, we investigated whether genistein could be employed as a novel strategy to enhance the anti-tumor activity of gemcitabine using human osteosarcoma MNNG/HOS tumor model. In vitro, by MTT, electron microscopy, immunobloting and qRT-PCR assay, we found that the combination treatment of genistein and gemcitabine resulted in stronger growth inhibition and apoptosis induction through the downregulation of NF-κB activity and Akt activation in osteosarcoma cells. Moreover, the synergetic effects were observed when genistein was replaced by PI3K/Akt-pathway inhibitor (LY-294002) or NF-κB inhibitor (BAY11-7082). In vivo, the combination therapy augmented tumor growth inhibition through the down-regulation of NF-κB activity and Akt activation in xenografts. Taken together, these results provide in vitro and in vivo evidence that genistein abrogates gemcitabine-induced activation of NF-κB and increases the chemosensitization of osteosarcoma to gemcitabine. Combination therapy appears as a rational and novel approach for osteosarcoma treatment. Keywords: Akt, Apoptosis, Gemcitabine, Genistein, NF-κB, Osteosarcoma, Immunoblotting, Electron Microscopy, Xenograft, Electrophoretic, Immunohistochemistry
OBJECTIVE To study the protective effect of carbon monoxide (CO) inhalation on the serious limb ischemia/reperfusion (I/R) injury, and which effects caused to shock in rats. METHODS 36 SD rats were randomly divided into I/R, I/R + CO (RC), sham operation (S) groups. I/R injury models were made by the occlusion of the femoral artery for 8 h and the reperfusion for 12 h, 10 d. Before reperfusion of 2 h, RC group started to breathe medical air containing CO (the volume fraction of CO: 0.075%) continuously, until after reperfusion for 4 h, a total of inhalation 6 h. S, I/R groups exposed to air, breathe freely. Caudal artery pressures (CAP), ten days survival rate, serum lactate dehydrogenase (LDH) and creatine kinase (CK) activity, limb wet - to - dry weight ratio (W/D) and the pathologic changes of limb were observed. RESULTS Once the reperfusion started, the CAP decreased rapidly in I/R group, and the mean reduced to(5.3259 +/- 0.3832) kPa when reperfusion for 8 h. Compared to I/R group, the CAP decreased slower and smaller in RC group, moreover, its mean reduced to (8.3300 +/- 0.4224) kPa when reperfusion for 8 h. The 10 d survival rate in I/R group was that 8 rats died all between reperfusion for 13 - 20 h. Only 1 rat died in RC group and the other 7 rats were still alive when reperfusion for 10 d. Compared to I/R group, the pathological features of the ischemic limb were significant ly improved, and the figures of W/D, serum LDH and CK value were remarkable lower in RC group (P < 0.05). CONCLUSION Inhaling exogenous low-dose CO has a reverse regulation in the blood pressure decline caused by serious limb I/R injury in rats. And at the same time, it can effectively prevent the occurrence of shock, reduce physical damage, significantly increase the survival rate of animals.