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1.
In vitro toxicity of silica nanoparticles in human lung cancer cells   总被引:7,自引:0,他引:7  
The cytotoxicity of 15-nm and 46-nm silica nanoparticles was investigated by using crystalline silica (Min-U-Sil 5) as a positive control in cultured human bronchoalveolar carcinoma-derived cells. Exposure to 15-nm or 46-nm SiO(2) nanoparticles for 48 h at dosage levels between 10 and 100 microg/ml decreased cell viability in a dose-dependent manner. Both SiO(2) nanoparticles were more cytotoxic than Min-U-Sil 5; however, the cytotoxicities of 15-nm and 46-nm silica nanoparticles were not significantly different. The 15-nm SiO(2) nanoparticles were used to determine time-dependent cytotoxicity and oxidative stress responses. Cell viability decreased significantly as a function of both nanoparticle dosage (10-100 microg/ml) and exposure time (24 h, 48 h, and 72 h). Indicators of oxidative stress and cytotoxicity, including total reactive oxygen species (ROS), glutathione, malondialdehyde, and lactate dehydrogenase, were quantitatively assessed. Exposure to SiO(2) nanoparticles increased ROS levels and reduced glutathione levels. The increased production of malondialdehyde and lactate dehydrogenase release from the cells indicated lipid peroxidation and membrane damage. In summary, exposure to SiO(2) nanoparticles results in a dose-dependent cytotoxicity in cultural human bronchoalveolar carcinoma-derived cells that is closely correlated to increased oxidative stress.  相似文献   

2.
Praziquantel has been shown to be highly effective against all known species of Schistosoma infecting humans. Spherical nanoparticulate drug carriers made of poly(d,l-lactide-co-glycolide) acid with controlled size were designed. Praziquantel, a hydrophobic molecule, was entrapped into the nanoparticles with theoretical loading varying from 10 to 30% (w/w). This study investigates the effects of some process variables on the size distribution of nanoparticles prepared by emulsion–solvent evaporation method. The results show that sonication time, PLGA and drug amounts, PVA concentration, ratio between aqueous and organic phases, and the method of solvent evaporation have a significant influence on size distribution of the nanoparticles.  相似文献   

3.
We have produced haloperidol-loaded PLGA/PLA nanoparticles by using two emulsification-solvent evaporation methods: homogenization and sonication. We have established how five independent processing parameters and two materials characteristics control the particle size and drug content. The interdependencies between processing and materials parameters and the subsequent nanoparticle characteristics are discussed in terms of underlying scientific principles that are broadly applicable to the production of drug-loaded polymer nanoparticles. This level of understanding should quicken the pace of designing protocols for making new drug-PLGA nanoparticles. It was determined that the particle size of haloperidol-loaded PLGA/PLA nanoparticles is effectively controlled by the amount of shear stress transferred from the energy source to the organic phase, which is strongly correlated to the following parameters: type of applied energy, aqueous phase volume, and polymer concentration in the organic solvent. The drug content of these nanoparticles is controlled by reducing the diffusion of the drug from the organic to the aqueous phase during the solvent evaporation stage of the preparation and by increasing the drug-polymer interactions. The following significantly inhibit drug diffusion: large particle size, higher polymer concentration and polymer molecular weight, and reducing the drug solubility in the aqueous phase by adjusting the pH. Specific drug-polymer interactions are engineered by optimizing the lactide to glycolide ratio (L:G ratio) and including specific polymer end groups. When optimized, the drug-loaded PLGA/PLA nanoparticles contain as much as 2.5% haloperidol.  相似文献   

4.
Resveratrol (RL), a natural polyphenol, is known for its diverse biological effects against various human cancer cell lines. But low aqueous solubility, poor bioavailability, and stability limit its efficacy against prostate cancer. In this study polymeric nanoparticles encapsulating resveratrol (RLPLGA) were designed and their cytotoxic and mode of apoptotic cells death against prostate cancer cell line (LNCaP) was determined. Nanoparticles were prepared by solvent displacement method and characterized for particle size, TEM, entrapment efficiency, DSC and drug release study. RLPLGA exhibited a significant decrease in cell viability with 50% and 90% inhibitory concentration (IC50 and IC90) of 15.6?±?1.49 and 41.1?±?2.19?μM respectively against the LNCaP cells. This effect was mediated by apoptosis as confirmed by cell cycle arrest at G1-S transition phase, externalization of phosphatidylserine, DNA nicking, loss of mitochondrial membrane potential and reactive oxygen species generation in LNCaP cells. Furthermore, significantly greater cytotoxicity to LNCaP cells was observed with nanoparticles as compared to that of free RL at all tested concentrations. RLPLGA nanoparticles presented no adverse cytotoxic effects on murine macrophages even at 200?μM. Our findings support the potential use of developed resveratrol loaded nanoparticle for the prostate cancer chemoprevention/ chemotherapy with no adverse effect on normal cells.  相似文献   

5.
The study aimed to design novel bioadhesive PLGA nanoparticles for efficient gene delivery to lung cancer cells. The bioadhesive agent and stabilizer, Carbopol 940 was chosen to establish bioadhesive PLGA nanoparticles and Pluronic F68, Pluronic F127 stabilized PLGA nanoparticles were formulated as control. The effects of different surfactants on the physicochemical and biological characterizations of PLGA nanoparticles were compared. All the obtained nanoparticles showed negative surface charge, similar spherical morphology, a relatively narrow particle size distribution, and lower cytotoxicity to A549 cells comparing with Lipofectamine 2000. Carbopol stabilized nanoparticles hold advantages in DNA-binding efficiency (>80%) at an optimal Carbopol concentration, DNA protection from enzymatic degradation in vitro release and better buffering capacity. Most importantly, higher transfection efficiency in A549 cells was observed comparing to Pluronics stabilized nanoparticles or naked DNA, similar to that of Lipofectamine 2000. These results revealed that the bioadhesive PLGA nanoparticles formulated with Carbopol might be a very attractive candidate as a non-viral vector for lung cancer gene therapy and might alleviate the drawbacks of the conventional cationic vectors/DNA complexes for gene delivery in vivo.  相似文献   

6.
PLGA nanoparticles simultaneously loaded with vincristine sulfate (VCR) and quercetin (QC) were prepared via O/W emulsion solvent evaporation. Six independent processing parameters and PLGA characteristics were assessed systematically to enhance the incorporation of the dual agents with different properties (VCR and QC, hydrophilic and hydrophobic molecule, respectively) into PLGA nanoparticles and control particle size. Approaches investigated for the enhancement of drug entrapment efficiencies and the controlling of particle size included the influence of the molecular weight (MW) of PLGA and the lactide-to-glycolide (L:G) ratio of PLGA, PLGA concentration, PVA concentration, initial QC content, acetone-to-dichloromethane (A/D) volume ratio, aqueous phase pH and aqueous to organic phase (W/O) volume ratio. The nanoparticles produced by optimal formulation were submicron size (139.5+/-4.3 nm, n=3) with low polydispersity index (0.095+/-0.031, n=3). Nanoparticles observed by transmission electron microscopy (TEM) showed extremely spherical shape. The entrapment efficiencies determined by high performance liquid chromatography (HPLC) by ultracentrifuge method were 92.84+/-3.37% for VCR and 32.66+/-2.92% for QC (n=3). The drug loadings were 0.0037+/-0.0001% for VCR and 1.36+/-0.12% for QC (n=3).  相似文献   

7.
Nanoparticles containing Zinc (II) Phthalocyanine (ZnPc) were prepared by a spontaneous emulsification diffusion method utilizing poly-(D,L lactic-co-glycolic acid) (PLGA), characterized and available in cellular culture. The process yield and encapsulation efficiency were 60% and 80%, respectively. The nanoparticles have a mean diameter of 200?nm, a narrow size distribution with polydispersive index of 0.15, smooth surface and spherical shape. ZnPc loaded nanoparticles maintain their photophysical behaviour after the encapsulation process. Photosensitizer released from nanoparticles was sustained with a burst effect of 10% for 3 days. The photocytotoxicity was evaluated on P388-D1 cells. They were incubated with ZnPc loaded Np by 6?h and exposed to light (675?nm) for 120?s, and light dose of 30?J?cm?2. After 24?h of incubation, the cellular viability was determined, obtaining 60% of cellular death. All the physical-chemical and photobiological measurements performed allowed one conclude that ZnPc loaded PLGA nanoparticles are a promising drug delivery system for PDT.  相似文献   

8.
Nelfinavir mesylate (NFV) is an anti-viral drug, used in the treatment of Acquired Immunodeficiency Syndrome (AIDS). Poor oral bioavailability and shorter half-life (3.5–5 h) remain a major clinical limitation of NFV leading to unpredictable drug bioavailability and frequent dosing. In this context, the objective of the present study was to formulate NFV loaded poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), which can increase the solubility and oral bioavailability along with sustained release of the drug. NFV loaded PLGA-NPs were prepared by nanoprecipitation method using PLGA and Poloxomer 407. The prepared NPs were evaluated for particle size, zeta potential, morphology, drug content, entrapment efficiency (EE) and in vitro dissolution studies. Oral bioavailability studies were carried out in New Zealand rabbits by administering developed NFV PLGA-NPs and pure drug suspension. PLGA-NPs prepared by using 1:4 ratio of drug and PLGA, with a stirring rate of 1500 rpm for 4 h. The prepared NPs were in the size of 185 ± 0.83 nm with a zeta potential of 28.7 ± 0.09 mV. The developed NPs were found to be spherical with uniform size distribution. The drug content and EE of the optimized formulation were found to be 36 ± 0.19% and 72 ± 0.47% respectively. After oral administration of NFV PLGA-NPs, the relative bioavailability was enhanced about 4.94 fold compared to NFV suspension as a control. The results describe an effective strategy for oral delivery of NFV loaded PLGA NPs that helps in enhancing bioavailability and reduce the frequency of dosing.  相似文献   

9.
Increasing utilization of engineered nanoparticles in the field of electronics and biomedical applications demands an assessment of risk associated with deliberate or accidental exposure. Metal based nanoparticles are potentially most important of all the nanoparticles in terms of health risks. Microporous alumino-silicates and pure silicates named as zeolites and zeo-type materials with variety of structures, chemical compositions, particle sizes and morphologies have a significant number of industrial uses such as in catalysis, sorption and ion-exchange processes. In particular, the nanosized particles due to their unique properties are used in hybrid organic-inorganic materials for photography, photonics, electronics, labeling, imaging, and sensing. The aim of the current study is to investigate pure silica MFI-type zeolites nanoparticles with sizes of 50 nm and 100 nm (samples MFI-50 and MFI-100) under suspended conditions and their toxicological effects on human lung alveolar (A549) cells under in vitro conditions.  相似文献   

10.
Cucurbitacin I is a hydrophobic molecule that exerts a degree of polarity, which is expected to complicate its loading in PLGA nanoparticles by the classical emulsion solvent evaporation technique. In the current study, variants of emulsion solvent evaporation method were used to prepare PLGA nanoparticles of cucurbitacin: CI-NP1 (single emulsion starting with 1000 μg drug), CI-NP2 (double emulsion starting with 250 μg drug), and CI-NP3 (double emulsion starting with 500 μg drug). On the other hand, CI-NP4 was prepared by nanoprecipitation (starting with 1000 μg drug). In CI-NP1, cucurbitacin I encapsulation efficiency (EE) was 1.29%. The employment of double emulsion, in CI-NP2 and CI-NP3, increased cucurbitacin I EE to 4.8% and 7.96%, respectively. Nanoprecipitation significantly increased the EE of cucurbitacin I to 48.79% in CI-NP4. It is likely that cucurbitacin I escapes with the organic solvent after the emulsification step to the aqueous phase leading to ineffective entrapment in the polymeric matrix. Avoiding emulsification seems efficient in increasing cucurbitacin I disposition in the instantly-precipitating NPs. Therefore, nanoprecipitation method increases cucurbitacin I entrapment in PLGA NPs and possibly other water-insoluble polar drugs.  相似文献   

11.
Many studies showed that transferrin increases brain delivery of nanoparticles (NPs) in vivo, however the mechanisms implied in their brain uptake are not yet clearly elucidated. In this study we evaluated the endocytosis of PLGA NPs coated with transferrin on an in vitro model of the blood–brain barrier (BBB) made of a co-culture of brain endothelial cells and astrocytes. PLGA NPs were prepared using DiI as a fluorescent marker and coated with Tween® 20, BSA and transferrin (Tf). Blank and BSA-NPs served as controls. The cellular toxicity on BBB of the different samples was evaluated following tight junction aperture and due to high toxicity NPs prepared with Tween® 20 were discarded. The size of the NPs prepared by the solvent diffusion method, varied from 63 to 90 nm depending on DiI incorporation and surface coating. Proteins adsorption on the surface of the NPs was found to be stable for at least 12 days at 37 °C. Contrary to Blank or BSA-NPs, Tf-NPs were found to be highly adsorbed by the cells and endocytosed using an energy-dependent process. Studies in presence of inhibitors suggest that Tf-NPs interact with the cells in a specific manner and enter the cells via the caveolae pathway.  相似文献   

12.
Nickel nanoparticle (Ni NP) is increasingly used in modern industries such as catalysts, sensors and electronic applications. Due to wide-spread industrial applications the inhalation is the primary source of exposure to Ni NPs. However, data demonstrating the effect of Ni NPs on the pulmonary system remain scarce. The present study was designed to examine the toxic effect of human lung epithelial A549 cells treated with well characterized Ni NPs at the concentrations of 0, 1, 2, 5, 10 and 25 μg/ml for 24 and 48 h. Mitochondrial function (MTT assay), membrane leakage of lactate dehydrogenase (LDH assay), reduced glutathione (GSH), reactive oxygen species (ROS), membrane lipid peroxidation (LPO) and caspase-3 activity were assessed as toxicity end points. Results showed that Ni NPs reduced mitochondrial function and induced the leakage of LDH in dose and time-dependent manner. Ni NPs were also found to induce oxidative stress in dose and time-dependent manner indicated by depletion of GSH and induction of ROS and LPO. Further, activity of caspase-3 enzyme, marker of apoptosis was significantly higher in treated cells with time and Ni NPs dosage. The results exhibited significant toxicity of Ni NPs in human lung epithelial A549 cells which is likely to be mediated through oxidative stress. This study warrants more careful assessment of Ni NPs before their industrial applications.  相似文献   

13.
方宁 《现代药物与临床》2019,42(8):1557-1562
目的 以聚乳酸-羟基乙酸共聚物(PLGA)作为纳米制剂载体材料将葫芦素B制备成纳米粒,并考察其对HepG2肝癌细胞的抑制效果。方法 使用乳化溶剂蒸发法制备葫芦素B-PLGA载药纳米粒,以PLGA浓度(X1)、PVA浓度(X2)和药物浓度(X3)作为考察因素,以载药纳米粒的粒径大小(Y1)和包封率(Y2)作为评价指标,应用中心复合设计-效应面法优化葫芦素B-PLGA载药纳米粒处方;测定了纳米粒的粒径分布和Zeta电位值,通过透射电镜观察其微观形态,并考察了葫芦素B-PLGA载药纳米粒的体外药物释放特性;比较了葫芦素B与葫芦素B-PLGA载药纳米粒对HepG2肝癌细胞的抑制效果。结果 葫芦素B-PLGA载药纳米粒的最优处方组成为:PLGA浓度为9.0%,PVA浓度为2.0%,药物浓度为4.5%,制备的纳米粒粒径为(145.4±15.8) nm,Zeta电位值为(-7.6±0.8) mV;透射电镜下可观察到纳米粒表面光滑,分布均匀;葫芦素B-PLGA载药纳米粒释药前期出现突释,后期平缓,48 h药物释放达到86%;葫芦素B-PLGA载药纳米粒对HepG2肝癌细胞的抑制作用显著高于葫芦素B。结论 葫芦素B-PLGA载药纳米粒可延缓药物释放,提高对HepG2肝癌细胞的抑制活性,为进一步临床研究奠定实验基础。  相似文献   

14.
Titanium dioxide (TiO2) are among most frequently used nanoparticles (NPs). They are present in a variety of consumer products, including food industry in which they are employed as an additive. The potential toxic effects of these NPs on mammal cells have been extensively studied. However, studies regarding neurotoxicity and specific effects on neuronal systems are very scarce and, to our knowledge, no studies on human neuronal cells have been reported so far. Therefore, the main objective of this work was to investigate the effects of two types of TiO2 NPs, with different crystalline structure, on human SHSY5Y neuronal cells. After NPs characterization, a battery of assays was performed to evaluate the viability, cytotoxicity, genotoxicity and oxidative damage in TiO2 NP-exposed SHSY5Y cells. Results obtained showed that the behaviour of both types of NPs resulted quite comparable. They did not reduce the viability of neuronal cells but were effectively internalized by the cells and induced dose-dependent cell cycle alterations, apoptosis by intrinsic pathway, and genotoxicity not related with double strand break production. Furthermore, all these effects were not associated with oxidative damage production and, consequently, further investigations on the specific mechanisms underlying the effects observed in this study are required.  相似文献   

15.
Metal oxide nanoparticles are often used as industrial catalysts and elevated levels of these particles have been clearly demonstrated at sites surrounding factories. To date, limited toxicity data on metal oxide nanoparticles are available. To understand the impact of these airborne pollutants on the respiratory system, airway epithelial (HEp-2) cells were exposed to increasing doses of silicon oxide (SiO2), ferric oxide (Fe2O3) and copper oxide (CuO) nanoparticles, the leading metal oxides found in ambient air surrounding factories. CuO induced the greatest amount of cytotoxicity in a dose-dependent manner; while even high doses (400 μg/cm2) of SiO2 and Fe2O3 were non-toxic to HEp-2 cells. Although all metal oxide nanoparticles were able to generate ROS in HEp-2 cells, CuO was better able to overwhelm antioxidant defenses (e.g. catalase and glutathione reductase). A significant increase in the level of 8-isoprostanes and in the ratio of GSSG to total glutathione in cells exposed to CuO suggested that ROS generated by CuO induced oxidative stress in HEp-2 cells. Co-treatment of cells with CuO and the antioxidant resveratrol increased cell viability suggesting that oxidative stress may be the cause of the cytotoxic effect of CuO. These studies demonstrated that there is a high degree of variability in the cytotoxic effects of metal oxides, that this variability is not due to the solubility of the transition metal, and that this variability appears to involve sustained oxidative stress possibly due to redox cycling.  相似文献   

16.
Melatonin loaded poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles and microparticles in the diameter of ~200?nm and 3.5?μm, respectively, were prepared by emulsion–diffusion–evaporation method. Melatonin entrapment into the particles was significantly improved with the addition of 0.2% (w/v) melatonin into the aqueous phase and encapsulation efficiencies were found as 14 and 27% for nanoparticles and microparticles, respectively. At the end of 40 days, ~70% of melatonin was released from both of particles, with high burst release. Both blank and melatonin loaded PLGA nanoparticles caused toxic effect on the MG-63 cells due to their uptake by the cells. However, when 0.05?mg microparticle that is carrying ~1.7?μg melatonin was added to the cm2 of culture, inhibitory effect of melatonin on the cells were obviously observed. The results would provide an expectation about the usage of melatonin as an adjunct to the routine chemotherapy of osteosarcoma by encapsulating it into a polymeric carrier system.  相似文献   

17.
PLGA nanoparticles simultaneously loaded with vincristine sulfate (VCR) and verapamil hydrochloride (VRP) were prepared via combining O/W emulsion solvent evaporation and salting-out method. Ten independent processing parameters and two materials characteristics were assessed systematically to enhance the incorporation of the two hydrophilic low molecular weight drugs into PLGA nanoparticles and minimize nanoparticles size. Approaches investigated for the enhancement of drug entrapment efficiencies and the minimization of particle size included the influence of the molecular weight (MW) of PLGA and the lactide to glycolide (L:G) ratio of PLGA, PLGA concentration, the degrees of hydrolyzation and polymerization of PVA, PVA concentration, initial VCR and VRP content, acetone to dichloromethane volume ratio, aqueous phase pH, salt concentration of aqueous phase, aqueous to organic phase volume ratio, sonication time, sonication energy and removal rate of organic solvents. The nanoparticles produced by optimal formulation were submicron size (111.4 ± 2.35 nm, n = 3) and of low polydispersity (0.062 ± 0.023, n = 3). Nanoparticles observed by transmission electron microscopy (TEM) showed extremely spherical shape. The entrapment efficiencies determined with high performance liquid chromatogram (HPLC) by ultracentrifuge method were 55.35 ± 4.22% for VCR and 69.47 ± 5.34% for VRP, respectively (n = 3).  相似文献   

18.
目的 优化影响盐酸维拉帕米乳酸/羟基乙酸共聚物(PLGA)纳米粒成型工艺的参数,并评价优化工艺后所制纳米粒的制剂学性质.方法 采用O/W超声乳化-溶剂挥发法制备盐酸维拉帕米PLGA纳米粒(VRP-PLGANP),以粒径、包封率和载药量为评价指标,采用单因素试验系统考察PLGA浓度、PLGA/VRP质量比、PVA浓度、有机相中丙酮浓度、外水相pH、内外相(O/W)体积比、探头超声时间、旋蒸时间共8个参数对纳米粒成型工艺的作用规律.结果 用优化处方工艺制备的纳米粒的包封率和载药量分别为65.78%±6.32%和22.75%±1.48%、平均粒径为150.4±6.9 nm、PDI=0.070±0.018(n=3),体外释放规律符合Weibull方程,具有一定的缓释特性.结论 所用方法可用于制备载两亲性药物的PLGA纳米粒.  相似文献   

19.
The present paper concerns both the optimization of dexamethasone (DXM) entrapment and its release from biodegradable poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles prepared by the solvent evaporation process. Since the addition of DXM induced the formation of drug crystals beside the nanoparticle suspension, the influence of several parameters on DXM encapsulation was investigated such as the type of organic solvent and polymer, the DXM initial mass, the evaporation rate of the solvent, the continuous phase saturation and the incorporation of a lipid in the polymer. Nanoparticle size and zeta potential were not modified in the presence of DXM and were respectively around 230 nm and -4 mV. The highest drug loading was obtained using 100 mg PLGA 75:25 in a mixture of acetone-dichloromethane 1:1 (v:v) and 10 mg of DXM. The drug was completely released from this optimized formulation after 4 h of incubation at 37 degrees C. Neither the evaporation rate of the organic solvent, nor the aqueous phase saturation with salt or the incorporation of 1mg 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) within the nanoparticles modified the encapsulation efficiency. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) demonstrated that the drug was molecularly dispersed within the nanoparticles whereas the non-encapsulated DXM crystallized. These results demonstrate the feasibility of encapsulating dexamethasone and its subsequent delivery.  相似文献   

20.
目的:制备无稳定剂修饰的汉防己甲素PLGA纳米粒,研究其理化性质及细胞毒和细胞摄取特性。方法:以聚乳酸-羟基醋酸共聚物(PLGA)为载体材料,采用无稳定剂修饰的纳米沉淀法制备汉防己甲素纳米粒;通过单因素试验考察不同制备工艺对纳米粒理化性质的影响;通过载药量、包封率、累积释药量等指标考察其载药特性;采用MTT比色法检测其对人肺腺癌细胞株A549的细胞毒性;采用共聚焦显微镜技术考察其细胞摄取特性。结果:无稳定剂修饰的汉防己甲素PLGA纳米粒平均粒径169.3 nm,与有稳定剂的汉防己甲素PLGA纳米粒相比外观无明显改变。在一定范围内,随着PLGA用量的增加,纳米粒的粒径呈上升趋势;随着投药量的增加,纳米粒的载药量显著增加,包封率下降。在pH7.4的释放介质中,纳米粒释慢释药,96 h累积释药率60.44%。细胞毒试验显示,当培养时间为8 h时,汉防己甲素组的细胞毒性大于汉防己甲素纳米粒组;当培养时间延长至24 h时,汉防己甲素纳米粒组的细胞活性明显低于纯药物组;高剂量的空白纳米粒组始终表现较低的细胞毒性。激光共聚焦电镜断层扫描显示汉防己甲素纳米粒能够较好的被细胞摄取。结论:制备的无稳定剂修饰的汉防己甲素PLGA纳米粒大小均一,包封率高,体外释药表现出较好的缓释效果,易被细胞摄取,对A549细胞的增殖有明显的抑制作用。  相似文献   

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