Silver nanoparticles (AgNPs) are widely used antimicrobial compounds; however, they may pose a threat to non-targeted bacteria in the environment. In this study high-throughput sequencing was used to investigate the...Silver nanoparticles (AgNPs) are widely used antimicrobial compounds; however, they may pose a threat to non-targeted bacteria in the environment. In this study high-throughput sequencing was used to investigate the effects of different concentrations of AgNPs (10, 50, and 100 mg kg-1) on soil microbial community structure during short-term (7 d) exposure. The amounts of Acidobacteria, Actinobacteria, Cyanobacteria, and Nitrospirae significantly decreased with increasing AgNP concentration; meanwhile, several other phyla (e.g., Proteobacteria and Planctomycetes) increased and dominated. Nitrosomonas europaea, a well-characterized ammonia- oxidizing bacterium, was used to study the sensitivity of bacteria to AgNPs and ionic silver (Ag+). Flow cytometry was used to monitor the toxicity of low (1 mg L-l), middle (10 mg L-l), and high concentrations (20 mg L-1) of AgNPs, as well as Ag+ (1 mg L-1) released into the medium from 20 mg L-1 concentration of AgNPs, towards N. europaea. After 12 h of exposure, the survival rate of N. europaea treated with 1 mg L-1 Ag+ was significantly lower than those treated with low (1 mg L-1) and middle concentrations (10 mg L-1) of AgNPs, but the survival rate in the treatment with high concentration (20 mg L-1) of AgNPs was much lower. Additionally, necrosis rates were higher in the treatment with 20 mg L-1 AgNPs. Electron microscopy showed that Ag+ caused serious damage to the cell wall of N. europaea, disintegrated the nucleoids, and condensed next to the cell membrane; however, dissolved Ag+ is only one of the antibacterial mechanisms of AgNPs.展开更多
OBJECTIVE To investigate the effect of endostatin and doxycycline on melanoma cellular proliferation and tumor angiogenesis.METHODS The effects of endostatin and doxycycline were studied in mice transplanted with B16 ...OBJECTIVE To investigate the effect of endostatin and doxycycline on melanoma cellular proliferation and tumor angiogenesis.METHODS The effects of endostatin and doxycycline were studied in mice transplanted with B16 melanoma cells. The mice were divided into 4 groups that were treated as follows: endostatin treatment (E group), doxycycline treatment (D group), endostatin plus doxycycline trearment (DE group), controls (C group) received no treatment. Following 9 days of treatment the tumor tissue was removed to compare the differences in the tumor necrotic rate and micro-vessel density (MVD) among the different groups. Immunohistochemical staining was conducted to detect the expression of proliferating cell nuclear antigen (PCNA) in the different groups.RESULTS The MVD of the 3 experimental groups was significantly less than the control group, (F = 10.888, P 〈 0.05), indicating that doxycycline and endostatin can inhibit tumor angiogenesis by decreasing the tumor blood supply. This effect results in inhibition of tumor cellular proliferation and promotion of tumor cell necrosis. The tumor cell necrotic rate of the 3 experimental groups were all significantly higher than the C group (F = 7.229, P 〈 0.05) and the difference between the DE and C groups also was statistically significant. PCNA expression in all 3 experimental groups was statistically less than the C group (F = 17.729, P 〈 0.05).CONCLUSION The combined use of endostatin and doxycycline in vivo can influence PCNA expression and angiogenesis in melanoma, and significantly inhibit melanoma cellular proliferation.展开更多
Objective: To study the influence of neoadjuvant chemotherapy on the expression of cyclin D1, Bcl-2, PCNA and P- gp in osteosarcoma cells and the relationship between the expression and tumor cell necrosis rate (TCNR)...Objective: To study the influence of neoadjuvant chemotherapy on the expression of cyclin D1, Bcl-2, PCNA and P- gp in osteosarcoma cells and the relationship between the expression and tumor cell necrosis rate (TCNR) after chemotherapy. Methods: By using immunohistochemistry, the expression of cyclin D1, Bcl-2, PCNA and P-gp was detected in 23 cases of osteosarcoma and TCNR were calculated. Results: The pre-chemotherapy positive expression rate of cyclin D1, Bcl-2, PCNA and P-gp was 73.9%, 69.6%, 91.3% and 21.7%, respectively, and that post-chemotherapy positive expression rate was 52.1%, 34.8%, 43.5% and 56.5%, respectively. The positive expression rate of Bcl-2 and PCNA after chemotherapy was much lower than that before chemotherapy (P=0.039, 0.034). After chemotherapy, the expression rate of P-gp was higher (P=0.021) and the expression of cyclin D1 had no statistically significant difference (P=0.180) comparing with that before chemotherapy. No correla- tion existed between the expression of cyclin D1, Bcl-2, PCNA, P-gp and TCNR before chemotherapy (P=0.155, 0.371, 1.000 and 0.640). There was a negative correlation between the expression of Bcl-2, PCNA, P-gp and TCNR (P=0.009, 0.012 and 0.015), but no relationship existed between the cyclin D1 and TCNR (P=0.100) after chemotherapy. Conclusion: Chemotherapy could inhibit proliferation and induce apoptosis of osteosarcoma cells. At the same time, due to the overexpression of the P-gp, the drug resistance of the osteosarcoma cells was increased. The detection of cyclin D1, Bcl-2, PCNA and P-gp in osteosarcoma samples before chemotherapy might not be used to predict the curative effect of the chemotherapy.展开更多
Objective To investigate effect of Pentoxifylline on free flap. Methods Forty Wistar rats were chosen as experimental models and free flaps were harvested from the back of rats,which as pect ratio was 3: 1. Then they ...Objective To investigate effect of Pentoxifylline on free flap. Methods Forty Wistar rats were chosen as experimental models and free flaps were harvested from the back of rats,which as pect ratio was 3: 1. Then they were divided into two groups randomly. Group A was as the experimental group,receiving drug treatment.展开更多
目的:研究骨碎补总黄酮对激素性股骨头坏死兔血磷、血钙及空骨陷窝率的作用机制。方法:选取实验用新西兰大白兔30只,其中8只为空白组,另22只兔经造模成功后随机选取8只为实验组,其余8只为模型组。实验组每天给予骨碎补总黄酮溶液6m L灌...目的:研究骨碎补总黄酮对激素性股骨头坏死兔血磷、血钙及空骨陷窝率的作用机制。方法:选取实验用新西兰大白兔30只,其中8只为空白组,另22只兔经造模成功后随机选取8只为实验组,其余8只为模型组。实验组每天给予骨碎补总黄酮溶液6m L灌胃1次,连续8周,空白组与模型组每天给予6m L 0.9%氯化钠溶液灌胃1次,连续8周。8周后检测各组新西兰大白兔血磷、血钙的变化情况,并解剖出股骨头在光镜下切片计算空骨陷窝比率,进行组间比较。结果:与空白组比较,模型组血钙明显减低(P<0.05);血磷及空骨窝比率显著升高(P<0.05);与模型组比较,实验组血钙显著升高(P<0.05),血磷及空骨陷窝比率水平均显著降低(P<0.05)。结论:骨碎补总黄酮通过改善激素性股骨头坏死对血磷、血钙的变化,改善空骨陷窝率,可能促进体外成骨细胞增殖及分化成熟,抑制破骨细胞活性、促进股骨头骨再生为骨碎补总黄酮治疗激素性股骨头坏死提供了初步理论依据。展开更多
基金supported by the National Natural Science Foundation of China (No. 41430752)
文摘Silver nanoparticles (AgNPs) are widely used antimicrobial compounds; however, they may pose a threat to non-targeted bacteria in the environment. In this study high-throughput sequencing was used to investigate the effects of different concentrations of AgNPs (10, 50, and 100 mg kg-1) on soil microbial community structure during short-term (7 d) exposure. The amounts of Acidobacteria, Actinobacteria, Cyanobacteria, and Nitrospirae significantly decreased with increasing AgNP concentration; meanwhile, several other phyla (e.g., Proteobacteria and Planctomycetes) increased and dominated. Nitrosomonas europaea, a well-characterized ammonia- oxidizing bacterium, was used to study the sensitivity of bacteria to AgNPs and ionic silver (Ag+). Flow cytometry was used to monitor the toxicity of low (1 mg L-l), middle (10 mg L-l), and high concentrations (20 mg L-1) of AgNPs, as well as Ag+ (1 mg L-1) released into the medium from 20 mg L-1 concentration of AgNPs, towards N. europaea. After 12 h of exposure, the survival rate of N. europaea treated with 1 mg L-1 Ag+ was significantly lower than those treated with low (1 mg L-1) and middle concentrations (10 mg L-1) of AgNPs, but the survival rate in the treatment with high concentration (20 mg L-1) of AgNPs was much lower. Additionally, necrosis rates were higher in the treatment with 20 mg L-1 AgNPs. Electron microscopy showed that Ag+ caused serious damage to the cell wall of N. europaea, disintegrated the nucleoids, and condensed next to the cell membrane; however, dissolved Ag+ is only one of the antibacterial mechanisms of AgNPs.
基金a grant from National Natural Science Foundation of China (No.30370554)
文摘OBJECTIVE To investigate the effect of endostatin and doxycycline on melanoma cellular proliferation and tumor angiogenesis.METHODS The effects of endostatin and doxycycline were studied in mice transplanted with B16 melanoma cells. The mice were divided into 4 groups that were treated as follows: endostatin treatment (E group), doxycycline treatment (D group), endostatin plus doxycycline trearment (DE group), controls (C group) received no treatment. Following 9 days of treatment the tumor tissue was removed to compare the differences in the tumor necrotic rate and micro-vessel density (MVD) among the different groups. Immunohistochemical staining was conducted to detect the expression of proliferating cell nuclear antigen (PCNA) in the different groups.RESULTS The MVD of the 3 experimental groups was significantly less than the control group, (F = 10.888, P 〈 0.05), indicating that doxycycline and endostatin can inhibit tumor angiogenesis by decreasing the tumor blood supply. This effect results in inhibition of tumor cellular proliferation and promotion of tumor cell necrosis. The tumor cell necrotic rate of the 3 experimental groups were all significantly higher than the C group (F = 7.229, P 〈 0.05) and the difference between the DE and C groups also was statistically significant. PCNA expression in all 3 experimental groups was statistically less than the C group (F = 17.729, P 〈 0.05).CONCLUSION The combined use of endostatin and doxycycline in vivo can influence PCNA expression and angiogenesis in melanoma, and significantly inhibit melanoma cellular proliferation.
文摘Objective: To study the influence of neoadjuvant chemotherapy on the expression of cyclin D1, Bcl-2, PCNA and P- gp in osteosarcoma cells and the relationship between the expression and tumor cell necrosis rate (TCNR) after chemotherapy. Methods: By using immunohistochemistry, the expression of cyclin D1, Bcl-2, PCNA and P-gp was detected in 23 cases of osteosarcoma and TCNR were calculated. Results: The pre-chemotherapy positive expression rate of cyclin D1, Bcl-2, PCNA and P-gp was 73.9%, 69.6%, 91.3% and 21.7%, respectively, and that post-chemotherapy positive expression rate was 52.1%, 34.8%, 43.5% and 56.5%, respectively. The positive expression rate of Bcl-2 and PCNA after chemotherapy was much lower than that before chemotherapy (P=0.039, 0.034). After chemotherapy, the expression rate of P-gp was higher (P=0.021) and the expression of cyclin D1 had no statistically significant difference (P=0.180) comparing with that before chemotherapy. No correla- tion existed between the expression of cyclin D1, Bcl-2, PCNA, P-gp and TCNR before chemotherapy (P=0.155, 0.371, 1.000 and 0.640). There was a negative correlation between the expression of Bcl-2, PCNA, P-gp and TCNR (P=0.009, 0.012 and 0.015), but no relationship existed between the cyclin D1 and TCNR (P=0.100) after chemotherapy. Conclusion: Chemotherapy could inhibit proliferation and induce apoptosis of osteosarcoma cells. At the same time, due to the overexpression of the P-gp, the drug resistance of the osteosarcoma cells was increased. The detection of cyclin D1, Bcl-2, PCNA and P-gp in osteosarcoma samples before chemotherapy might not be used to predict the curative effect of the chemotherapy.
文摘Objective To investigate effect of Pentoxifylline on free flap. Methods Forty Wistar rats were chosen as experimental models and free flaps were harvested from the back of rats,which as pect ratio was 3: 1. Then they were divided into two groups randomly. Group A was as the experimental group,receiving drug treatment.
文摘目的:研究骨碎补总黄酮对激素性股骨头坏死兔血磷、血钙及空骨陷窝率的作用机制。方法:选取实验用新西兰大白兔30只,其中8只为空白组,另22只兔经造模成功后随机选取8只为实验组,其余8只为模型组。实验组每天给予骨碎补总黄酮溶液6m L灌胃1次,连续8周,空白组与模型组每天给予6m L 0.9%氯化钠溶液灌胃1次,连续8周。8周后检测各组新西兰大白兔血磷、血钙的变化情况,并解剖出股骨头在光镜下切片计算空骨陷窝比率,进行组间比较。结果:与空白组比较,模型组血钙明显减低(P<0.05);血磷及空骨窝比率显著升高(P<0.05);与模型组比较,实验组血钙显著升高(P<0.05),血磷及空骨陷窝比率水平均显著降低(P<0.05)。结论:骨碎补总黄酮通过改善激素性股骨头坏死对血磷、血钙的变化,改善空骨陷窝率,可能促进体外成骨细胞增殖及分化成熟,抑制破骨细胞活性、促进股骨头骨再生为骨碎补总黄酮治疗激素性股骨头坏死提供了初步理论依据。