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  • Research progress on the effect of iron oxide nanoparticles in macrophage polarization

    Macrophages are important immune effector cells with significant plasticity and heterogeneity in the body immune system, and play an important role in normal physiological conditions and in the process of inflammation. It has been found that macrophage polarization involves a variety of cytokines and is a key link in immune regulation. Targeting macrophages by nanoparticles has a certain impact on the occurrence and development of a variety of diseases. Due to its characteristics, iron oxide nanoparticles have been used as the medium and carrier for cancer diagnosis and treatment, making full use of the special microenvironment of tumors to actively or passively aggregate drugs in tumor tissues, which has a good application prospect. However, the specific regulatory mechanism of reprogramming macrophages using iron oxide nanoparticles remains to be further explored. In this paper, the classification, polarization effect and metabolic mechanism of macrophages were firstly described. Secondly, the application of iron oxide nanoparticles and the induction of macrophage reprogramming were reviewed. Finally, the research prospect and difficulties and challenges of iron oxide nanoparticles were discussed to provide basic data and theoretical support for further research on the mechanism of the polarization effect of nanoparticles on macrophages.

    Release date:2023-06-25 02:49 Export PDF Favorites Scan
  • Numerical simulation on the deposition characteristics of inhaled particles in human pulmonary acinus region under the influence of multi-factors

    Research on the deposition of inhaled particles in human pulmonary acinus region is important to the pathogenesis investigation, prevention and treatment of lung diseases. Most of the current research focus on the final deposition fraction of inhaled particles in human acinar region, but little is involved in their dynamic deposition characteristics. In this paper, five multi-alveolar models, G3−G7, were built. The evaluation parameter 1/4 deposition time was introduced to study the particle deposition speed. The deposition characteristics of particles in the diameter ranging 0.1−5 μm were numerically simulated and summarized under the influence of factors such as the generation and structure of model, particle diameter and respiratory mode, shedding some new light on the further research of transport of inhaled particles. The results showed that the generation and structure of model had a significance effect on the deposition of particles. 0.1 μm particles were dominated by Brownian diffusion, which experienced a high deposition fraction, a fast deposition speed and a logarithmic deposition curve, while 5 μm particles were dominated by gravitational sedimentation, with a high deposition fraction, a fast deposition speed and an S-shaped deposition curve. The deposition of 0.3−1 μm particles were influenced greatly by convention and varied with the change of respiratory mode. The research methods and results in this paper can provide theoretical basis and data support for the further exploration of the mechanism, prevention and treatment of lung diseases.

    Release date:2020-12-14 05:08 Export PDF Favorites Scan
  • EXPERIMENTAL STUDY ON POLYACTIC GLYCOLATE ACID MICROPARTICLES WITH RELEASINGSLOWLY VASCULAR ENDOTHELIAL GROWTH FACTOR

    Objective To observe the degradation of the polyactic glycolate acid (PLGA) microparticles with releasing-slowly vascular endothelial growth factor(VEGF) synthesized by the method of emulsification-diffusion. Methods The method of emulsification-diffusion is to incorporate VEGF into microparticles composed of biodegradable PLGA. The controlled release of microparticles are acquired. The content of the VEGF released slowly from PLGA microparticles in vitro was detected with ELISA at different time. Results We synthesized 100 releasing-slowly VEGF PLGA microparticles with the size of 0.20-0.33 μm by 5 times. The contents were 62±11 ng/L, 89±14 ng/L, and 127±19 ng/L in the 1st, the 2nd and the 3rd months after degradation, respectively. Conclusion The PLGAmicroparticles with releasing-slowly VEGF can be synthesized by the method of emulsification-diffusion.

    Release date:2016-09-01 09:29 Export PDF Favorites Scan
  • Antifriction and anti-wear performances of bionic lubricating fluid containing gelatin nanoparticles for artificial joint materials

    ObjectiveThe antifriction and antiwear effects of gelatin nanoparticles (GLN-NP) on artificial joint materials in bionic joint lubricant were investigated to provide a theoretical basis for the development of new bionic joint lubricant. MethodsGLN-NP was prepared by cross-linking collagen acid (type A) gelatin with glutaraldehyde by acetone method, and the particle size and stability of GLN-NP were characterized. The biomimetic joint lubricants with different concentrations were prepared by mixing 5, 15, and 30 mg/mL GLN-NP with 15 and 30 mg/mL hyaluronic acid (HA), respectively. The friction reduction and antiwear effects of the biomimetic joint lubricants on zirconia ceramics were investigated on a tribometer. The cytotoxicity of each component of bionic joint lubricant on RAW264.7 mouse macrophages was evaluated by MTT assay. ResultsThe particle size of GLN-NP was about 139 nm, and the particle size distribution index was 0.17, showing a single peak, indicating that the particle size of GLN-NP was uniform. In complete culture medium, pH7.4 PBS, and deionized water at simulated body temperature, the particle size of GLN-NP did not change more than 10 nm with time, indicating that GLN-NP had good dispersion stability and did not aggregate. Compared with 15 mg/mL HA, 30 mg/mL HA, and normal saline, the friction coefficient, wear scar depth, width, and wear volume were significantly reduced by adding different concentrations of GLN-NP (P<0.05); there was no significant difference between different concentrations of GLN-NP (P>0.05). Biocompatibility test showed that the cell survival rate of GLN-NP, HA, and HA+GLN-NP solution decreased slightly with the increase of concentration, but the cell survival rate was more than 90%, and there was no significant difference between groups (P>0.05). ConclusionThe bionic joint fluid containing GLN-NP has good antifriction and antiwear effect. Among them, GLN-NP saline solution without HA has the best antifriction and antiwear effect.

    Release date:2023-02-13 09:57 Export PDF Favorites Scan
  • Preparation and Property Evaluation of Graphene Oxide Based Silver Nanoparticles Composite Materials

    We prepared silver nanoparticles/polyethyleneimine-reduction graphene oxide (AgNP/rGO-PEI) composite materials, and evaluated their quality performance in our center. Firstly, we prepared AgNP/rGO-PEI, and then analysed its stability, antibacterial activity, and cellular toxicity by comparing the AgNP/rGO-PEI with the silver nanoparticles (PVP/AgNP) modified by polyvinylpyrrolidone. We found in the study that silver nanoparticles (AgNP) distributed relatively uniformly in AgNP/rGO-PEI surface, silver nanoparticles mass fraction was 4.5%, and particle size was 6-13 nm. In dark or in low illumination light intensity of 3 000 lx meter environment (lux) for 10 days, PVP/AgNP aggregation was more obvious, but the AgNP/rGO-PEI had good dispersibility and its aggregation was not obvious; AgNP/rGO-PEI had a more excellent antibacterial activity, biological compatibility and relatively low biological toxicity. It was concluded that AgNP/rGO-PEI composite materials had reliable quality and good performance, and would have broad application prospects in the future.

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  • Injection of carbon nanoparticle suspension for Surgical Patients with non-small cell lung cancer

    Abstract: Surgery is an effective therapy for non-small cell lung cancer (NSCLC). The standard operation includes lobectomy and systematic dissection of lymph nodes. However, postoperative tumor recurrence is common even among incipient patients due to incomplete dissection of lymph nodes and micrometastasis of lymph nodes. Injecting a carbon nanoparticles suspension is a new technique aimed at preventing this recurrence. The carbon nanoparticles carry lymph node tracers that help surgeons locate lymph nodes in order to clean them thoroughly. The tracers also target the lymph nodes for chemotherapy, thus killing residual tumor cells intraoperatively to avoid postoperative cancer recurrence. Carbon nanoparticles suspension injection is already widely and successfully used in surgery for gastrointestinal and mammary gland tumors, and is being tested for effectiveness in NSCLC patients. Some studies have indicated that carbon nanoparticles suspension injection is effective in NSCLC patients and improves their prognoses. We reviewed the features, application methods, and clinical applications of studies of carbon nanoparticles suspension injection for NSCLC.

    Release date:2016-08-30 05:48 Export PDF Favorites Scan
  • Progress on numerical simulation of the deposition of inhaled particles in human pulmonary acinus region

    The inhalation and deposition of particles in human pulmonary acinus region can cause lung diseases. Numerical simulation of the deposition of inhaled particles in the pulmonary acinus region has offered an effective gateway to the prevention and clinical treatment of these diseases. Based on some important affecting factors such as pulmonary acinar models, model motion, breathing patterns, particulate characteristics, lung diseases and ages, the present research results of numerical simulation in human pulmonary acinus region were summarized and analyzed, and the future development directions were put forward in this paper, providing new insights into the further research and application of the numerical simulation in the pulmonary acinus region.

    Release date:2019-06-17 04:41 Export PDF Favorites Scan
  • The Property with Adsorption and Slow Release of Carbon Nanoparticles Suspension Injection for Epirubicin Solution in Vitro

    Objective To determine the best matching concentration of carbon nanoparticles suspension injection adsorb epirubicin by measuring the combination ratio of carbon nanoparticles suspension injection combined with epirubicin under different matching conditions. And then, to prove the adsorbability of carbon nanoparticles suspension injection adsorb epirubicin in vitro. Methods Firstly, epirubicin-carbon suspension of different concentrations will be prepared. The second, high performance liquid chromatography mass spectrometry(LC-MS) was used to assay the concentration of free epirubicin, and calculate the content of epirubicin that was combinated with carbon nanoparticles suspension injection. The difference of the ratio of carbon nanoparticles suspension injection combined with epirubicin under different matching conditions will be compared in the end. Results The combination ratio of carbon nanoparticles suspension injection combined with epirubicin solution of 5, 10, and 15 mg/ml were 85.6%, 85.7%, and 31.8%, respectively. Conclusions The adsorbability of carbon nanoparticles suspension injection adsorb epirubicin is favourable in vitro. Best matching concentration of carbon nanoparticles suspension injection adsorb epirubicin may be epirubicin solution of 5-10 mg/ml.

    Release date:2016-09-08 10:38 Export PDF Favorites Scan
  • PSO+: nonlinear fitting fluorescence data based on particle swarm optimizing combine with other iteration algorithm

    The convective polymerase chain reaction (CCPCR) uses the principle of thermal convection to allow the reagent to flow in the test tube and achieve the purpose of amplification by the temperature difference between the upper and lower portions of the test tube. In order to detect the amplification effect in real time, we added a fluorophore to the reagent system to reflect the amplification in real time through the intensity of fluorescence. The experimental results show that the fluorescence curve conforms to the S-type trend of the amplification curve, but there is a certain jitter condition due to the instability of the thermal convection, which is not conducive to the calculation of the cycle threshold (CT value). In order to solve this problem, this paper uses the dynamic method, using the double S-type function model to fit the curve, so that the fluorescence curve is smooth and the initial concentration of the nucleic acid can be deduced better to achieve the quantitative purpose based on the curve. At the same time, the PSO+ algorithm is used to solve the double s-type function parameters, that is, particle swarm optimization (PSO) algorithm combined with Levenberg-Marquardt, Newton-CG and other algorithms for curve fitting. The proposed method effectively overcoms PSO randomness and the shortcoming of traditional algorithms such as Levenberg-Marquardt and Newton-CG which are easy to fall into the local optimal solution. The R2 of the data fitting result can reach 0.999 8. This study is of guiding significance for the future quantitative detection of real-time fluorescent heat convection amplification.

    Release date:2019-06-17 04:41 Export PDF Favorites Scan
  • Expression of Caspase-3 in Targeted Therapy with Magnetic Nanoparticle in Cholangiocarcinoma Xenograft of Nude Mice

    Objective To investigate the expression of caspase-3 in xenograft that was treated with targeted therapy with magnetic nanoparticles in nude mice. Methods QBC939 cell lines were injected into nude mice subcutaneously to establish the model of human cholangiocarcinoma xenograft. After two weeks of tumor inoculation, the animal models were divided randomly into 4 groups: group A received placebo (sodium chloride), group B were treated with magnetic nanoparticles (250 mg/kg), group C were treated with magnetic nanoparticles (150 mg /kg) combined with inner-stent, group D with magnetic nanoparticles (250 mg /kg) combined with inner-stent (the inner-stent was used to generate the magnetic targeting effect). The 21th day after treatment, expression of caspase-3 in tumor cells of each groups were measured with histochemical method and RT-PCR. Results The quantity of caspase-3 in tumor cells that were treated with magnetic nanoparticles (250 mg/kg) combined with inner-stent was the most (P<0.05), and the quantity of caspase-3 in cells of group C was significantly more than that of the other two groups (P<0.05). While the quantity of caspase-3 in group B was more than that of the control group(P<0.05). Conclusion The use of magnetic nanoparticles combined with inner-stent may increase the expression of caspase-3, and the expression is dose-dependent with magnetic nanoparticles.

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