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find Keyword "nanoparticles" 27 results
  • Precise Dissection of Lymph Node Guided by Carbon Nanoparticles in Reoperation for Thyroid Cancer Recurrence

    ObjectiveTo investigate the value of carbon nanoparticle adopted in reoperation for thyroid cancer recurrence. MethodsFrom July to November of 2015, patients diagnosed with thyroid cancer recurrence in department of Thyroid & Parathyroid surgery, West China Hospital, Sichuan University were enrolled in the research. All enrollment patients underwent carbon nanoparticles location guided by ultrasonography before reoperation. Relative data about surgery and location were analyzed retrospectively. ResultsTwenty-two patients were enrolled in the research. Mean operation time was (60.45±12.91) minutes. During surgery, a total of 405 (average 18.4) lymph nodes were harvested, and the staining rate was 71.9% (291/405). The pathological examination showed that there was a significant difference in the positive rate between carbon nanoparticles stained lymph nodes (45.0%, 131/291) and non-stained lymph nodes (5.3%, 6/114), P < 0.001. In addition, the positive rate in non-targeted stained lymph nodes was 30.2% (62/205). By contrast, it was 5.3% (6/114) in non-targeted non-stained lymph nodes. The difference showed significant significance (P < 0.001). ConclusionsAdoption of carbon nanoparticles in reoperation for thyroid cancer, which improves efficiency of dissection for the non-palpable lymph nodes metastasis, is worth generalizing in clinical practice.

    Release date:2016-10-25 06:10 Export PDF Favorites Scan
  • A study of locally injecting curcumin-loaded mesoporous silica nanoparticles in delaying coccygeal intervertebral disc degeneration in rats

    Objective To investigate the effect of local injection of curcumin-loaded mesoporous silica nanoparticles (Cur@MSN) on the repair and treatment of degenerative intervertebral disc tissue in rats, and provide a new strategy for the treatment of intervertebral disc degeneration. Methods Mesoporous silica nanoparticles (MSN) and Cur@MSN were prepared according to the method reported in the literature. Rat nucleus pulposus cells were co-cultured with curcumin and Cur@MSN, respectively, and the growth status and activity of cells in normal environment and inflammatory environment (adding lipopolysaccharide) were observed respectively. Twelve 8-week-old SD rats were randomly divided into 4 groups, including normal group, degeneration group, curcumin group, and Cur@MSN group, with 3 rats in each group. Acupuncture degeneration model was established in coccygeal intervertebral discs (Co7-8, Co8-9) of rats, and corresponding intervention were injected. Imaging, gross pathology, and histological examination were performed after 4 weeks, respectively, to observe the tissue structure and pathological changes of intervertebral discs. Results Under scanning electron microscope, Cur@MSN was spherical in shape, with groove-like pores on its surface. Particle size analysis showed that the particle size of MSN was concentrated in 120-160 nm, and that of Cur@MSN was distributed in 130-170 nm. Zeta potential analysis showed that the average Zeta potential of MSN, curcumin, and Cur@MSN was −12.5, −22.5 and −13.5 mV, respectively. The entrapment efficiency of Cur@MSN was 20.4%, and the drug loading rate was 0.2%. Curcumin released by Cur@MSN in 12 h accounted for about 60% of the total drug dose, and curcumin released in 28 h accounted for about 70%. In cell experiment, there was no significant difference in cell proliferation absorbance among the groups in normal environment (P>0.05), but the cell proliferation absorbance in the Cur@MSN group on the 3rd and 5th day in inflammatory environment was significantly higher than that in the control group and the curcumin group (P<0.01). The percentage of disc height index and the Pfirrmann grade of the Cur@MSN group were better than those of the degeneration group and the curcumin group (P<0.01). The histological score of the Cur@MSN group was lower than that of the degeneration group and the curcumin group (P<0.01). Conclusions Cur@MSN can delay the degeneration process of rat coccygeal intervertebral disc, and has certain repair and treatment effects on its degenerated intervertebral disc. Among them, curcumin can delay the degeneration of intervertebral disc by inhibiting inflammation, and the loading of MSN is helpful for curcumin to exert its biological effects.

    Release date:2024-05-28 01:17 Export PDF Favorites Scan
  • Preparation and Characterization of Chitosan-Poloxamer-based Antibacterial Hydrogel Containing Silver Nanoparticles

    In order to solve the problem of high cytotoxicity in vitro of nano-silver antibacterial gel, and the problem of large nano-silver particle size and size distribution, this study prepared nano-silver antibacterial gel with better biocompatibility and good antibacterial effect by using physical cross-linking method and using poloxamer as dispersant when prepared nano-silver. In this study, nano-silver was prepared by photo-initiator method and by adding poloxamer as a dispersant, and then UV-visible absorption spectrum test and scanning electron microscopy (SEM) test were carried out using prepared nano-silver mixture and particles after drying respectively. The gel was prepared through adjusting its pH value by using sodium bicarbonate, and then pH value test, SEM test for cross-section of gel, swelling ratio test, viscosity test, inhibition zone test and in vitro cytotoxicity test were carried out. The test results showed that the maximum absorption wavelength of prepared nano-silver, using poloxamer as dispersant and ultra-pure water as solvent, was 414 nm, and the average nano-silver size was about 60 nm. The prepared nano-silver using poloxamer as dispersant had smaller particle diameter and narrower particle size distribution than those using PVP as dispersant. Similarly, the prepared nano-silver using ultra-pure water as solvent also had smaller particle diameter and narrower particle size distribution than those using distilled water as solvent. The pH value of the prepared gel was between 5.8~6.1. The dried gel section had many holes. The water absorption of gel was fine and the viscosity of gel was fit to coat on the gauze. In addition, the prepared gel with nano-silver had greater ability to inhibit Escherichia coli and Staphyloccocus aureus at the concentrations of 24, 18 and 12 μg/mL. And the biocompatibility of the prepared gel with nano-silver was good when the concentration below 24 μg/mL. Based on the above features, the nano-silver antibacterial gel could be used in the treatment of burn or other wounds.

    Release date:2016-12-19 11:20 Export PDF Favorites Scan
  • Effect of Carbon Nanoparticles Dyeing on Axillary Lymph Node Dissection in Modified Radical Mastectomy for Breast Cancer

    Objective To explore the effect of carbon nanoparticles dyeing on axillary lymph node dissection in modified radical mastectomy for breast cancer. Methods Eighty-eight patients with breast cancer who received modified radical mastectomy in Mianyang Central Hospital between Mar. 2012 and May. 2013 were recruited in the study, and they were equally divided into areola group and peripheral tumor group. After induction of anesthesia before operation, carbon nanoparticles were injected around the areolar in the areola group, and carbon nanoparticles were injected around the tumor in the peripheral tumor group. The number of dissected lymph nodes(be dyed or not be dyed), metastatic lymph nodes, and black dyed lymph nodes, as well as value of operation related indexes were recorded and compared. Results In the areola group, lymph nodes were detected in 1 453, in which 1 396 lymph nodes were stained black(96.1%); the average number of dissected lymph nodes were 33.0±7.1 per case; and 19 patients (43.2%, in total of 220 metastatic lymph nodes) of them were suffered from lymph node metastasis with the average number of metastatic lymph nodes of 5±2 per case. in addition, in the areola group, operative time were(122.1±10.2) min, blood loss were(83.8±10.1) mL, postoperative hospital stay were(7±1) d, and postoperative complications occurred in 3 patients. In the peripheral tumor group, lymph nodes were detected in 909, in which 594 lymph nodes were stained black (65.3%); the average number of dissected lymph nodes were 20.7±3.2 per case; 20 patients (45.5%, in total of 88 metastatic lymph nodes) of them were suffered from lymph nodes metastasis, with the average number of metastatic lymph nodes of 2±1 per case. In addition, in the peripheral tumor group, operative time were (121.6±11.4) min, blood loss were (84.2±11.3) mL, postoperative hospital stay were (7±2) d, postoperative complications occurred in 3 patients. The black staining rate of lymph nodes, the number of lymph nodes retrieved, and the number of metastatic lymph nodes in areola group were significantly higher than those of peripheral tumor group(P < 0.01). Operative time, blood loss, postoperative hospital stay, and postoperative complication rate did not significantly differ between the 2 groups (P > 0.05). Conclusion The dyeing effect of carbon nanoparticles suspension, which was injected at areola area after induction of anesthesia, is better than that of injected around the tumor, without increasing the incidence of complication.

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  • Study on the thermal field distribution of cholangiocarcinoma model by magnetic fluid hyperthermia

    Cholangiocarcinoma is a highly malignant tumor. It is not sensitive to radiotherapy and chemotherapy and has a poor prognosis. At present, there is no effective treatment. As a new method for treating cancer, magnetic fluid hyperthermia has been clinically applied to a variety of cancers in recent years. This article introduces it to the cholangiocarcinoma model and systematically studies the effect of magnetic fluid hyperthermia on cholangiocarcinoma. Starting from the theory of magnetic fluid heating, the electromagnetic and heat transfer models were constructed in the finite element simulation software COMSOL using the Pennes biological heat transfer equation. The Helmholtz coil was used as an alternating magnetic field generating device. The relationship between the magnetic fluid-related properties and the heating power was analyzed according to Rosensweig’s theory. After the multiphysics coupling simulation was performed, the electromagnetic field and thermal field distribution in the hyperthermia region were obtained. The results showed that the magnetic field distribution in the treatment area was uniform, and the thermal field distribution met the requirements of hyperthermia. After the magnetic fluid injection, the cholangiocarcinoma tissue warmed up rapidly, and the temperature of tumor tissues could reach above 42 °C, but the surrounding healthy tissues did not heat up significantly. At the same time, it was verified that the large blood vessels around the bile duct, the overflow of the magnetic fluid, and the eddy current heat had little effect on thermotherapy. The results of this article can provide a reference for the clinical application of magnetic fluid hyperthermia for cholangiocarcinoma.

    Release date:2021-08-16 04:59 Export PDF Favorites Scan
  • Effect of Lymph Node-Targeted Chemotherapy with Carbon Nanoparticles Absorbing 5-Fluorouracil on Expressions of bcl-2, bax and Caspase-3 in Gastric Cancer Tissues and Metastatic Lymph Nodes

    Objective To determine whether lymph node-targeted chemotherapy with carbon nanoparticles absorbing 5-FU affects expressions of bcl-2, bax and caspase-3 in gastric cancer tissues, metastatic lymph nodes and normal gastric mucosa. Methods Twenty-eight patients with gastric cancer in our department were divided into lymph node-targeted chemotherapy (LNTC) group and control group from October 2005 to August 2006. The patients were treated with carbon nanoparticles absorbing 5-FU before operation in LNTC group and those were operated directly in control group. The gastric cancer tissues, metastatic lymph nodes and normal gastric mucosa were collected after operation. The expressions of bcl-2, bax and caspase-3 in those tissues were determined by immunohistochemical technique. Results In LNTC group, the positive expression rate of bcl-2 in gastric cancer tissues and metastatic lymph nodes was significantly lower than those in control group (28.6% vs . 78.6% , 25.0% vs . 70.0% , P < 0.05), the positive expression rate of bax (85.7% vs . 28.6% , 80.0% vs . 30.0% ) and caspase-3 (57.1% vs . 14.3% , 55.0% vs . 15.0% ) in gastric cancer tissues and metastatic lymph nodes was significantly higher than those in control group ( P < 0.05). The positive expression rate of bcl-2, bax and caspase-3 in normal gastric mucosa was not significantly different between two groups ( P > 0.05). Conclusion The lymph node-targeted chemotherapy with carbon nanoparticles absorbing 5-FU can down-regulate the expression of bcl-2 and up-regulate the expression of bax and caspase-3 in gastric cancer tissues and metastatic lymph nodes, and therefore by affecting the expression levels of these apoptosis molecules may be one of the ways to induce tumor cell apoptosis.

    Release date:2016-08-28 03:48 Export PDF Favorites Scan
  • Influence of Fe2O3 nanoparticles on the rhological properties of simulated asthma airway mucus

    The properties of mucus in a person with asthma can alter with disease process so that it may lead to the airway embolism. Fe2O3 nanoparticles can be used for drug delivery. Up till now, however, little is known about how the Fe2O3 nanoparticles influence the properties of airway mucus. In this study, Fe2O3 nanoparticles were dispersed with ultrasound, and the morphological properties were measured with scanning electron microscope, atomic force microscope and nanometer laser particle size and zeta potential analyzer. Then the dispersed Fe2O3 nanoparticles were added to the simulated asthma airway mucus with different final concentration (0.03, 0.3, and 0.4 mg/mL). The measurements of flow curve, yield stress, large amplitude oscillatory shear (LAOS) and shock scanning were carried out with a rotational rheometer. Experimental results showed that the Fe2O3 nanoparticles reduced the zero shear viscosity of simulated asthma airway mucus. With increase of shear rate, the wind speed of mucus was reduced. The yield stress of simulated asthma airway mucus was 19.0 Pa, but the yield stresses of experimental group (0.03, 0.3 and 0.4 mg/mL) were 17.0, 0.99, and 0.7 Pa, respectively. The results showed that the viscoelastic modulus of asthma airway mucus treated with Fe2O3 nanoparticles were changed obviously as measured with large amplitude scanning and frequency scanning. By adopting the method of optical phase microscopy, we found that different structures of simulated airway mucus were absorbed. The results showed Fe2O3 nanoparticles distroyed mucus structure. The experimental results proved that Fe2O3 nanoparticles could change the rheological characteristics of simulated asthma airway mucus. This experimental result would lay a foundation for the further development of airway mucus sticky agent based on the function of Fe2O3 nanoparticles.

    Release date:2017-04-13 10:03 Export PDF Favorites Scan
  • Effect of silver nanoparticles on Staphylococcus aureus biofilm formation on different orthopedic biomaterials

    Objective To observe the inhibitory characteristics of silver nanoparticles (AgNP) on bacterial biofilms and investigate their inhibitory effect on biofilm formation on three common orthopedic biomaterials. Methods The minimal inhibitory concentration (MIC) and minimal biofilm inhibitory concentration (MBIC) of AgNP were determined by microplate dilution assay. Biofilms of Staphylococcus aureus (ATCC 25923) were cultured on three orthopedic biomaterials (titanium alloy, titanium oxide, and stainless steel) and intervened with AgNP at concentrations of 32, 16, 8, 4, 2 and 0 μg/mL to determine the MBICs on the three materials. The effects of AgNP on biofilm formation were analyzed by scanning electron microscopy and measuring optical density. Results The MIC and MBIC of AgNP in the microplate assay were both 16 µg/mL. The MBICs of AgNP on biofilm formation in titanium oxide, titanium alloy, and stainless steel were 16 μg/mL, 32 μg/mL, and 32 μg/mL, respectively. Among the three materials, the lowest optical density was observed on titanium oxide, while the highest was on titanium alloy. Conclusions AgNP has strong antibacterial biofilm characteristics and can prevent the formation of Staphylococcus aureus biofilm in vitro. Biofilm formation is most pronounced on titanium alloy, least on titanium oxide, and intermediate on stainless steel.

    Release date:2023-08-24 10:24 Export PDF Favorites Scan
  • Study on application value of carbon nanoparticles during operation of differentiated thyroid cancer

    ObjectiveTo explore the application value of carbon nanoparticles during radical operation of differentiated thyroid cancer (DTC).MethodsThe DTC patients underwent total thyroidectomy plus neck lymph node (area Ⅳ) dissection from September 2017 to September 2019 in this hospital were retrospectively collected, who were divided into observation group and control group according to using carbon nanoparticles or not during the operation. The operation related informations [operation time, intraoperative blood loss, total drainage volume on day 3 after operation, postoperative hospitalization time, number of lymph nodes dissection (area Ⅳ), lymph node metastasis rate, and rate of parathyroid glands resected by mistake during operation] and blood calcium (Ca2+) level and parathyroid hormone (PTH) level before and after (24 h and 1 month) operation were compared between the two groups.ResultsA total of 134 patients with DTC were collected, including 76 patients in the observation group and 58 patients in the control group. There were no significant differences in baseline data such as gender, age, etc. between the two groups (P>0.05). Although there were no significant differences in terms of operation time, intraoperative blood loss, total drainage volume on day 3 after operation, postoperative hospitalization time, lymph node metastasis rate between the two groups (P>0.05), the numbers of lymph node dissection and metastasis (area Ⅳ) were more and rate of parathyroid glands resected by mistake during operation was lower in the observation group as compared with the control group (P<0.05). On hour 24 after operation, the levels of Ca2+ and PTH in the observation group were higher than those in the control group (P<0.05). On month 1 after operation, the PTH level in the observation group was still higher than that in the control group (P<0.05), but there was no significant difference in Ca2+ level between the two groups (P>0.05). ConclusionCarbon nanoparticles can better protect the function of parathyroid gland during radical operation of DTC and clean neck lymph nodes more thoroughly.

    Release date:2021-04-30 10:45 Export PDF Favorites Scan
  • Effect of Gold (Au) Nanoparticles Modified by Surface Chemistry on the Proliferation and Migration of Hepatocellular Carcinoma Cells in Vitro

    Due to the good tumor-targeting and excellent biocompatibility, the drug-loading nanoparticles (NPs) has been widely applied in the diagnosis and treatment of cancer. However, after the NPs are recognized and internalized by cancer cells, the effects of NPs on cell migration behavior were unclear. In the present study, the self-assembly techniques (SAMs) was used to modify gold (Au) nanoparticles (Au NPs) with different chemical functional groups (CH3, OH, COOH and NH2) as model NPs. The dispersion of these groups in solution and the distribution in cells were studied by transmission electron microscope (TEM), respectively, and the proliferation was examined by MTT assay in vitro. The wound-healing and the Transwell assay were used to examine the effect of internalized Au-NPs on HepG2 cells migration. The results showed that different Au-NPs mainly distributed at the edge of the vesicle membrane and the gap between cells. The Au-NPs resulted in decreased cell viability in a concentration-depended manner. In addition, the results of wound-healing and Transwells assay indicated that the internalization of the NH2-NPs and OH-NPs would inhibit cell migration compared with those in the control group.

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