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.
Melanin nanoparticles (MNPs) not only retain the inherent characteristics of melanin (metal ion chelation, photothermal conversion property, etc.), but also can exhibit more excellent properties, such as high dispersion stability, good biocompatibility and biodegradability, etc. Furthermore, these performances can be enhanced to target the specific sites and treat diseases by the surface modification or combination with functional substance. In this paper, the characteristics, preparation methods and applications of MNPs were reviewed. It provides a reference for further development of application for MNPs, and theoretical basis for practice in biology, medicine and so on.
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.
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.
As drug carriers, magnetic nanoparticles can specifically bind to tumors and have the potential for targeted therapy. It is of great significance to explore non-invasive imaging methods that can detect the distribution of magnetic nanoparticles. Based on the mechanism that magnetic nanoparticles can generate ultrasonic waves through the pulsed magnetic field excitation, the sound pressure wave equation containing the concentration information of magnetic nanoparticles was derived. Using the finite element method and the analytical solution, the consistent transient pulsed magnetic field was obtained. A three-dimensional simulation model was constructed for the coupling calculation of electromagnetic field and sound field. The simulation results verified that the sound pressure waveform at the detection point reflected the position of magnetic nanoparticles in biological tissue. Using the sound pressure data detected by the ultrasonic transducer, the B-scan imaging of the magnetic nanoparticles was achieved. The maximum error of the target area position was 1.56%, and the magnetic nanoparticles regions with different concentrations were distinguished by comparing the amplitude of the boundary signals in the image. Studies in this paper indicate that B-scan imaging can quickly and accurately obtain the dimensional and positional information of the target region and is expected to be used for the detection of magnetic nanoparticles in targeted therapy.
Objective To investigate an inhibitive effect of the chitosan nanoparticles with the proliferation cell nuclear antigen （PCNA）-antisense oligo deoxy nucleotides (ASODN) on the intimal cell proliferation after the vein grafting.Methods Fiftyfour male SD rats, weighing 450-600g, were randomly divided in the experimental group and the control group of 27 rats each. In the experimental group, the chitosan nanoparticles with PCNAASODN were infused into the anastomosis segment of the right jugular artery and vein; then, the anastomosis segment was transplanted to the jugular artery on the same side. The rats in the control group were infused with normal saline by the same procedures. There were 24 rats in each group which used to experiment. The hemodynamic data were obtained from the Doppler ultrasound examinations at 1, 2, 3 and 4 weeks. The specimens were taken. Immunohistochemistry, Westernblot, and bloodvesselwall histopathology were performed at the different week points. Results There was no significant difference in the thrombogenesis rate between the experimental group and the control group (3/27 vs. 3/27,P＞0.05). During the 4 week observation, PCNA Westernblot showed that the PCNA level was lower in the grafted vein and the anastomosis segment in the experimental group than in the control group. The indexes of the PCNA postive proliferating cells in the intimal area (0.13%±0.11%，0.79%±0.28%，0.45%±0.29%, 0.43%±0.25%) and the medial area (1.90%± 0.84%，2.11%±0.98%，2.48%±0.77%，2.17%±0.36%) were significantlydecreased at 1,2,3 and 4 weeks in the experimental group when compared with those in the control group（P＜0.05）. The lumen areas in the grafted vein (88.71±16.96，95.98±21.44，88.48±32.81，97.86±34.11 μm 2) and the anastomosis segment (41.49±3.34，45.15±11.65，46.27±8.90，51.62±8.85 μm 2) were significantly greater in the experimental group than in the control group (P＜0.05). The ratios of the initmal area to the medial area in the grafted vein (22.73%±3.11%，32.40%±4.55%，45.14%±3.19%，45.70%±5.01%) and the anastomsis segment (41.49%±3.34%，45.15%±11.65%，46.27%±890%，51.62%±8.85%) were significantly smaller in the experimental group than in the control group（P＜0.05）. The maximum velocities (Vmax) of the blood flow inthe grafted vein and the anastomsis segment were almost the same in the two groups at 1 week, but had different changes at the next 3 weekpoints. In the control group, the Vmax of the blood flow gradually increased and at 3 weeks it reached the peak point; however, at 4 weeks it decreased. In the experimental group,the Vmax of the blood flow gradually decreased, and at 3 weeks it decreased to the lowest point; however, at 4 weeks it increased. So, at 4 weeks the Vmax of the blood flow in the grafted vein and the anastomsis segment was almost the samein the two groups. There was no significant difference in the Vmax of the bloodflow between the two groups (P＞0.05), but in the same group there wasa significant difference at the different time points. Conclusion The chitosan nanoparticles with PCNAASODN can effectively inhibit the intimal cell proliferation after the grafting of the blood vessel, so that the neointimal thickening can be prevented.
Objective To evaluate the feasibility of sentinel lymph node (SLN) mapping after 99Tcm sulfur colloid (99Tcm-sc) and carbon nanoparticles injection in patients with colon cancer. Methods Forty patients with colon cancer underwent complete mesocolic excision between August 2015 and July 2016 at Qingdao Central Hospital were considered for prospective inclusion. Before resection, SLN mapping was performed with injection of 99Tcm-sc and carbon nanopar-ticles, then all dissected lymph nodes were detected by pathological examination. Results A total of 660 cases of lymph nodes were found in the 40 patients (average of 16.5 cases per patient). Of them, 88 nodes (average of 2.2 cases per patient) were identified as SLN in 36 of 40 patients, with a successful detection rate of 90.0% (36/40). The diagnostic accuracy, sensitivity, and false-negative rate were 87.5% (35/40), 96.2% (25/26), and 3.8% (1/26) respectively. Conclusion 99Tcm-sc and carbon nanoparticles suspension injection for mapping SLN is a feasiblely diagnostic method for predicting local lymph node metastasis in the patient with colon 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.
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.
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.