Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a p...Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning.展开更多
To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are es...To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are established firstly on the basis of advanced dynamics principle. and the exterior ballistics equations are deduced. Then the equations of scanning trails are established by the method of space analytic geometry. To get the scanning trails. the differential equations are transformed into discrete simulation model using the algorithm of fourth order Runge-Kutta and then are simulated using Matlab. Compared with the scanning trails obtained by the traditional layout of scanner, the scanning trails obtained by the proposed layout of scanner has larger horizontal range of scanning circle and bigger trarget acquisition probability. Therefore, the new arrangement mode of the scanner for intelligent mine can increase attack range.展开更多
Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular ...Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV-1 from 29 immunosuppressed animals. It was possible to obtain 18 isolates, each from a different animal, such as from the respiratory and reproductive tracts. In some cases the cytopathic effect was visible 12 hours post-inoculation, and became characteristic after 36-48 hours. Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains, and differences were found in plaque size, virus titer measured by TCID50 and PFU/mL, and one step virus curves. These results showed that some isolates had a highly virulent-like behavior in vitro, compared to the reference strains, with shorter eclipse periods, faster release of virus into the supernatants, and higher burst size and viral titer. There were no differences in glycoprotein expression of BoHV-1 isolates, measured by Western blot on monolayers. Moreover, using restriction endonucleases analysis, most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype. These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines.展开更多
AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analys...AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation assay.The cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting.The pathological changes of the tumor cells were observed by haematoxylin and eosin staining.Tumor growth inhibition and side effects were determined in a xenograft mouse model.RESULTS:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase.The number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P<0.05).SSE induced caspase-dependent apoptosis accompanied by a significant decrease in Bcl-xl and Mcl-1 and elevation of Bak expression (P<0.05).Tumor necrosis factor α in the xenograft tumor tissue and the liver functions of SSE-treated mice showed no significant changes at week 8 compared with the control group (P>0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.CONCLUSION:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.展开更多
AIM:To determine the effects of curcumin,(-)-epigallocatechin-3-gallate (EGCG),lovastatin,and their combinations on inhibition of esophageal cancer.METHODS:Esophageal cancer TE-8 and SKGT-4 cell lines were subjected t...AIM:To determine the effects of curcumin,(-)-epigallocatechin-3-gallate (EGCG),lovastatin,and their combinations on inhibition of esophageal cancer.METHODS:Esophageal cancer TE-8 and SKGT-4 cell lines were subjected to cell viability methyl thiazolyl tetrazolium and tumor cell invasion assays in vitro and tumor formation and growth in nude mouse xenografts with or without curcumin,EGCG and lovastatin treatment.Gene expression was detected using immunohistochemistry and Western blotting in tumor cell lines,tumor xenografts and human esophageal cancer tissues,respectively.RESULTS:These drugs individually or in combinations significantly reduced the viability and invasion capacity of esophageal cancer cells in vitro.Molecularly,these three agents reduced the expression of phosphorylated extracellular-signal-regulated kinases (Erk1/2),c-Jun and cyclooxygenase-2 (COX-2),but activated caspase 3 in esophageal cancer cells.The nude mouse xenograft assay showed that EGCG and the combinations of curcumin,EGCG and lovastatin suppressed esophageal cancer cell growth and reduced the expression of Ki67,phosphorylated Erk1/2 and COX-2.The expression of phosphorylated Erk1/2 and COX-2 in esophageal cancer tissue specimens was also analyzed using immunohistochemistry.The data demonstrated that 77 of 156 (49.4%) tumors expressed phosphorylated Erk1/2 and that 121 of 156 (77.6%) esophageal cancers expressed COX-2 protein.In particular,phosphorylated Erk1/2 was expressed in 23 of 50 (46%) cases of esophageal squamous cell carcinoma (SCC) and in 54 of 106 (50.9%) cases of adenocarcinoma,while COX-2 was expressed in 39 of 50 (78%) esophageal SCC and in 82 of 106 (77.4%) esophageal adenocarcinoma.CONCLUSION:The combinations of curcumin,EGCG and lovastatin were able to suppress esophageal cancer cell growth in vitro and in nude mouse xenografts,these drugs also inhibited phosphorylated Erk1/2,c-Jun and COX-2 expression.展开更多
Lymphocystis disease virus(LCDV) infects target cells by attaching to a 27.8 k Da receptor(27.8R) protein in flounder Paralichthys olivaceus, and anti-27.8R monoclonal antibodies(MAbs) have been developed. However, th...Lymphocystis disease virus(LCDV) infects target cells by attaching to a 27.8 k Da receptor(27.8R) protein in flounder Paralichthys olivaceus, and anti-27.8R monoclonal antibodies(MAbs) have been developed. However, the 27.8R existence in tissues of sea bass(Lateolabrax japonicus) and its role in LCDV infection have remained unclear. In this study, the results of western blotting demonstrated that the same 27.8R was shared by flounder and sea bass. LCDV-free sea bass individuals were intramuscularly injected with LCDV, and viral copies were detected in tissues from 3 h post infection and showed a time-dependent increase during 9 days infection. Distribution and synthesis of 27.8R in sea bass tissues were investigated by using anti-27.8R MAbs as probes. It was found that 27.8R was distributed in all the tested tissues. The levels of 27.8R protein were highest in gill and skin, then a bit lowly in stomach, head kidney and heart, followed by spleen, intestine, blood cells, gonad and liver, and least in kidney and brain in healthy sea bass. Upon LCDV infection, 27.8R synthesis was up-regulated in each tissue, and higher in the tissues with higher LCDV copies. The 27.8R and LCDV were detected in some peripheral blood leukocytes but not in red blood cells. These results suggested that 27.8R was widely distributed in sea bass tissues, and it served as a receptor and correlated with tissue tropism of LCDV infection. Furthermore, leukocytes had the potential of being a LCDV carrier and were responsible for a systemic infection of LCDV in sea bass.展开更多
Surgical accesses to lesions of the posterolateral pontomesencephalic junction(PMJ)region and the posterolateral tentorial gap remain a challenge in the field of neurosurgery.Since the first report of application of...Surgical accesses to lesions of the posterolateral pontomesencephalic junction(PMJ)region and the posterolateral tentorial gap remain a challenge in the field of neurosurgery.Since the first report of application of the extreme lateral supracerebellar infratentorial(ELSI)approach in resecting the PMJ lesions in 2000,a few articles concerning the ELSI approach have been published.The present review mainly provided an intimate introduction of the ELSI approach,and evalu- ated it in facets of patient position,skin incision,craniectomy,draining veins,retraction against the cerebellum,exposure limits,patient healing,as well as advantages and limitations compared with other approaches.The ELSI approach is proposed to be a very young and promising approach to access the lesions of posterolateral PMJ region and the posterolateral tentorial gap.Besides,it has several advantages such as having a shorter surgical pathway,causing less surgical complications,laborsaving,etc.Still,more studies are needed to improve this approach.展开更多
OBJECTIVE: To study the anticancer mechanism of polyphyllin I (PPI), a Traditional Chinese Medicine, on the ovarian cancer cell line HO-8910PM in vitro. METHODS: Transwell chamber invasive assays were used to inve...OBJECTIVE: To study the anticancer mechanism of polyphyllin I (PPI), a Traditional Chinese Medicine, on the ovarian cancer cell line HO-8910PM in vitro. METHODS: Transwell chamber invasive assays were used to investigate the inhibitory capacity of PPI on HO-8910PM metastasis. Gene expression profiling chips was used to screen differentially ex- pressed genes between experiment group and con- trol group. Reverse transcription PCR and Western blotting were used to determine mRNA and pro- tein levels. RESULTS: With increasing PPI concentration, the metastatic capacity of cells decreased, with signifi- cance differences between the experimental and control groups (P〈0.01) as well as between two concentration groups. Gene expression profiling identified 123 differentially expressed genes, of which 70 were downregulated and 53 were upregu- lated. The genes were involved in multiple signal transduction pathways, including apoptosis, prolif- eration and metastasis. Real-time PCR (RT-PCR) showed that differential genes PIK3C2B, Caspase 9and WntSA were downregulated with increasing PPI, showing an evident dose-effect relationship. The c-Jun was an exception. As the PPI dosage in- creased and the exposure time was extended, c-Jun relative expression showed an upward trend. There were significant differences between the ex- periment and control (P〈0.05). Western blot analy- ses showed that PPI treatment decreased levels of Caspase 9, WntSA and PIK3C2B and increased acti- vated Caspase 9,c-Jun and p-c-Jun expression levels. CONCLUSION" PPI has strong antitumor and anti transfer activity. It can activate c-Jun expression and the JNK signaling pathway, elicit cell apoptosis via the mitochondrial-mediated Caspase activation pathway, and finally inhibit tumor growth and mi- gration in vitro. The downregulation of PIK3C2B and Wnt5A jointly inhibit the proliferation and me- tastasis of HO-8910PM. PPI may be a novel treat- ment for ovarian cancer.展开更多
The in vitro and in vivo anti-tumor efficacy of methotrexate-loaded Fe3O4-poly-L-lactide-poly(ethylene glycol)-poly-L-lactide magnetic composite microspheres(MTX-Fe3O4-PLLA-PEG-PLLA MCMs,MMCMs),which were produced by ...The in vitro and in vivo anti-tumor efficacy of methotrexate-loaded Fe3O4-poly-L-lactide-poly(ethylene glycol)-poly-L-lactide magnetic composite microspheres(MTX-Fe3O4-PLLA-PEG-PLLA MCMs,MMCMs),which were produced by co-precipitation(C)and microencapsulation(M)in a supercritical process,was evaluated at various levels:cellular,molecular,and integrated.The results at the cellular level indicate that MMCMs(M)show a better anti-proliferation activity than raw MTX and could induce morphological changes of cells undergoing apoptosis.At the molecular level,MMCMs(M)lead to a significantly higher relative mRNA expression of bax/bcl-2 and caspase-3 than MMCMs(C)at 10μg mL-1(P<0.01);and the pro-caspase-3protein expression measured by Western blot analysis also demonstrates that MMCMs(M)can effectively activate pro-caspase-3.At the integrated level,mice bearing a sarcoma-180 tumor are used;in vivo anti-tumor activity tests reveal that MMCMs(M)with magnetic induction display a much higher tumor suppression rate and lower toxicity than raw MTX.Pharmacokinetic studies show that MMCMs(M)with magnetic induction significantly increase the accumulation of MTX in the tumor tissue compared with the other treatments.These results suggest that the MMCMs(M)prepared by the SpEDS process have great potential to play a positive role in the magnetic targeted therapy field.展开更多
基金supported in part by the National Natural Science Foundation of China(Nos.42271448,41701531)the Key Laboratory of Land Satellite Remote Sensing Application,Ministry of Natural Resources of the People’s Republic of China(No.KLSMNRG202317)。
文摘Under single-satellite observation,the parameter estimation of the boost phase of high-precision space noncooperative targets requires prior information.To improve the accuracy without prior information,we propose a parameter estimation model of the boost phase based on trajectory plane parametric cutting.The use of the plane passing through the geo-center and the cutting sequence line of sight(LOS)generates the trajectory-cutting plane.With the coefficient of the trajectory cutting plane directly used as the parameter to be estimated,a motion parameter estimation model in space non-cooperative targets is established,and the Gauss-Newton iteration method is used to solve the flight parameters.The experimental results show that the estimation algorithm proposed in this paper weakly relies on prior information and has higher estimation accuracy,providing a practical new idea and method for the parameter estimation of space non-cooperative targets under single-satellite warning.
文摘To expand scanning area and attack range without changing the inner structure of intelligent warhead, a new arrangement mode of the scanner for intelligent mine is proposed. The required coordinate systems are established firstly on the basis of advanced dynamics principle. and the exterior ballistics equations are deduced. Then the equations of scanning trails are established by the method of space analytic geometry. To get the scanning trails. the differential equations are transformed into discrete simulation model using the algorithm of fourth order Runge-Kutta and then are simulated using Matlab. Compared with the scanning trails obtained by the traditional layout of scanner, the scanning trails obtained by the proposed layout of scanner has larger horizontal range of scanning circle and bigger trarget acquisition probability. Therefore, the new arrangement mode of the scanner for intelligent mine can increase attack range.
基金the División de Investigación Universidad Nacional de Colombia,grants No.20201007738 and 202010013254
文摘Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV-1 from 29 immunosuppressed animals. It was possible to obtain 18 isolates, each from a different animal, such as from the respiratory and reproductive tracts. In some cases the cytopathic effect was visible 12 hours post-inoculation, and became characteristic after 36-48 hours. Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains, and differences were found in plaque size, virus titer measured by TCID50 and PFU/mL, and one step virus curves. These results showed that some isolates had a highly virulent-like behavior in vitro, compared to the reference strains, with shorter eclipse periods, faster release of virus into the supernatants, and higher burst size and viral titer. There were no differences in glycoprotein expression of BoHV-1 isolates, measured by Western blot on monolayers. Moreover, using restriction endonucleases analysis, most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype. These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines.
基金Supported by National Science and Technology Key Project for the Development of New Drugs in China,No. 2009ZX09103-422
文摘AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of action.METHODS:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation assay.The cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting.The pathological changes of the tumor cells were observed by haematoxylin and eosin staining.Tumor growth inhibition and side effects were determined in a xenograft mouse model.RESULTS:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase.The number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P<0.05).SSE induced caspase-dependent apoptosis accompanied by a significant decrease in Bcl-xl and Mcl-1 and elevation of Bak expression (P<0.05).Tumor necrosis factor α in the xenograft tumor tissue and the liver functions of SSE-treated mice showed no significant changes at week 8 compared with the control group (P>0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.CONCLUSION:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.
基金Supported by A United States National Cancer Institute Grant,No.R01CA117895a grant from the Duncan Family Institute for Cancer Prevention and Risk Assessment,UT MDAnderson Cancer Center
文摘AIM:To determine the effects of curcumin,(-)-epigallocatechin-3-gallate (EGCG),lovastatin,and their combinations on inhibition of esophageal cancer.METHODS:Esophageal cancer TE-8 and SKGT-4 cell lines were subjected to cell viability methyl thiazolyl tetrazolium and tumor cell invasion assays in vitro and tumor formation and growth in nude mouse xenografts with or without curcumin,EGCG and lovastatin treatment.Gene expression was detected using immunohistochemistry and Western blotting in tumor cell lines,tumor xenografts and human esophageal cancer tissues,respectively.RESULTS:These drugs individually or in combinations significantly reduced the viability and invasion capacity of esophageal cancer cells in vitro.Molecularly,these three agents reduced the expression of phosphorylated extracellular-signal-regulated kinases (Erk1/2),c-Jun and cyclooxygenase-2 (COX-2),but activated caspase 3 in esophageal cancer cells.The nude mouse xenograft assay showed that EGCG and the combinations of curcumin,EGCG and lovastatin suppressed esophageal cancer cell growth and reduced the expression of Ki67,phosphorylated Erk1/2 and COX-2.The expression of phosphorylated Erk1/2 and COX-2 in esophageal cancer tissue specimens was also analyzed using immunohistochemistry.The data demonstrated that 77 of 156 (49.4%) tumors expressed phosphorylated Erk1/2 and that 121 of 156 (77.6%) esophageal cancers expressed COX-2 protein.In particular,phosphorylated Erk1/2 was expressed in 23 of 50 (46%) cases of esophageal squamous cell carcinoma (SCC) and in 54 of 106 (50.9%) cases of adenocarcinoma,while COX-2 was expressed in 39 of 50 (78%) esophageal SCC and in 82 of 106 (77.4%) esophageal adenocarcinoma.CONCLUSION:The combinations of curcumin,EGCG and lovastatin were able to suppress esophageal cancer cell growth in vitro and in nude mouse xenografts,these drugs also inhibited phosphorylated Erk1/2,c-Jun and COX-2 expression.
基金the National Natural Science Foundation of China (Nos. 31472295 and 31672685)Science and Technology Development Project of Shandong Province (No. 2014GNC111015)Taishan Scholar Program of Shandong Province
文摘Lymphocystis disease virus(LCDV) infects target cells by attaching to a 27.8 k Da receptor(27.8R) protein in flounder Paralichthys olivaceus, and anti-27.8R monoclonal antibodies(MAbs) have been developed. However, the 27.8R existence in tissues of sea bass(Lateolabrax japonicus) and its role in LCDV infection have remained unclear. In this study, the results of western blotting demonstrated that the same 27.8R was shared by flounder and sea bass. LCDV-free sea bass individuals were intramuscularly injected with LCDV, and viral copies were detected in tissues from 3 h post infection and showed a time-dependent increase during 9 days infection. Distribution and synthesis of 27.8R in sea bass tissues were investigated by using anti-27.8R MAbs as probes. It was found that 27.8R was distributed in all the tested tissues. The levels of 27.8R protein were highest in gill and skin, then a bit lowly in stomach, head kidney and heart, followed by spleen, intestine, blood cells, gonad and liver, and least in kidney and brain in healthy sea bass. Upon LCDV infection, 27.8R synthesis was up-regulated in each tissue, and higher in the tissues with higher LCDV copies. The 27.8R and LCDV were detected in some peripheral blood leukocytes but not in red blood cells. These results suggested that 27.8R was widely distributed in sea bass tissues, and it served as a receptor and correlated with tissue tropism of LCDV infection. Furthermore, leukocytes had the potential of being a LCDV carrier and were responsible for a systemic infection of LCDV in sea bass.
基金supported by the grants from Natural Science Foundation of Shandong Province(No.Z2008C12,Y2006C13)
文摘Surgical accesses to lesions of the posterolateral pontomesencephalic junction(PMJ)region and the posterolateral tentorial gap remain a challenge in the field of neurosurgery.Since the first report of application of the extreme lateral supracerebellar infratentorial(ELSI)approach in resecting the PMJ lesions in 2000,a few articles concerning the ELSI approach have been published.The present review mainly provided an intimate introduction of the ELSI approach,and evalu- ated it in facets of patient position,skin incision,craniectomy,draining veins,retraction against the cerebellum,exposure limits,patient healing,as well as advantages and limitations compared with other approaches.The ELSI approach is proposed to be a very young and promising approach to access the lesions of posterolateral PMJ region and the posterolateral tentorial gap.Besides,it has several advantages such as having a shorter surgical pathway,causing less surgical complications,laborsaving,etc.Still,more studies are needed to improve this approach.
基金Supported by Grant from the Zhejiang Province Natural Science Fund of Youth in China(No.LQ12H16015)
文摘OBJECTIVE: To study the anticancer mechanism of polyphyllin I (PPI), a Traditional Chinese Medicine, on the ovarian cancer cell line HO-8910PM in vitro. METHODS: Transwell chamber invasive assays were used to investigate the inhibitory capacity of PPI on HO-8910PM metastasis. Gene expression profiling chips was used to screen differentially ex- pressed genes between experiment group and con- trol group. Reverse transcription PCR and Western blotting were used to determine mRNA and pro- tein levels. RESULTS: With increasing PPI concentration, the metastatic capacity of cells decreased, with signifi- cance differences between the experimental and control groups (P〈0.01) as well as between two concentration groups. Gene expression profiling identified 123 differentially expressed genes, of which 70 were downregulated and 53 were upregu- lated. The genes were involved in multiple signal transduction pathways, including apoptosis, prolif- eration and metastasis. Real-time PCR (RT-PCR) showed that differential genes PIK3C2B, Caspase 9and WntSA were downregulated with increasing PPI, showing an evident dose-effect relationship. The c-Jun was an exception. As the PPI dosage in- creased and the exposure time was extended, c-Jun relative expression showed an upward trend. There were significant differences between the ex- periment and control (P〈0.05). Western blot analy- ses showed that PPI treatment decreased levels of Caspase 9, WntSA and PIK3C2B and increased acti- vated Caspase 9,c-Jun and p-c-Jun expression levels. CONCLUSION" PPI has strong antitumor and anti transfer activity. It can activate c-Jun expression and the JNK signaling pathway, elicit cell apoptosis via the mitochondrial-mediated Caspase activation pathway, and finally inhibit tumor growth and mi- gration in vitro. The downregulation of PIK3C2B and Wnt5A jointly inhibit the proliferation and me- tastasis of HO-8910PM. PPI may be a novel treat- ment for ovarian cancer.
基金supported by the National Natural Science Foundation of China (51103049,31170939)Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University (ZQN-PY107)+1 种基金Science and Technology Project of Fujian Province (2013Y2002)Specialized Research Fund for the Doctoral Program of Higher Education (20133501110003)
文摘The in vitro and in vivo anti-tumor efficacy of methotrexate-loaded Fe3O4-poly-L-lactide-poly(ethylene glycol)-poly-L-lactide magnetic composite microspheres(MTX-Fe3O4-PLLA-PEG-PLLA MCMs,MMCMs),which were produced by co-precipitation(C)and microencapsulation(M)in a supercritical process,was evaluated at various levels:cellular,molecular,and integrated.The results at the cellular level indicate that MMCMs(M)show a better anti-proliferation activity than raw MTX and could induce morphological changes of cells undergoing apoptosis.At the molecular level,MMCMs(M)lead to a significantly higher relative mRNA expression of bax/bcl-2 and caspase-3 than MMCMs(C)at 10μg mL-1(P<0.01);and the pro-caspase-3protein expression measured by Western blot analysis also demonstrates that MMCMs(M)can effectively activate pro-caspase-3.At the integrated level,mice bearing a sarcoma-180 tumor are used;in vivo anti-tumor activity tests reveal that MMCMs(M)with magnetic induction display a much higher tumor suppression rate and lower toxicity than raw MTX.Pharmacokinetic studies show that MMCMs(M)with magnetic induction significantly increase the accumulation of MTX in the tumor tissue compared with the other treatments.These results suggest that the MMCMs(M)prepared by the SpEDS process have great potential to play a positive role in the magnetic targeted therapy field.