Multidrug resistance (MDR) remains the major obstacle to the success of clinical cancer chemotherapy. P-glycoprotein (P-gp), encoded by the MDR1, is an important part with complex mechanisms associated with the MDR. In order to overcome the MDR of tumors, we in the present experimental design incorporated small interfering RNA (siRNA) targeting MDR1 gene and anticancer drug paclitaxel (PTX) into the solid lipid nanoparticles (SLNs) to achieve the combinational therapeutic effects of genetherapy and chemotherapy. In this study, siRNA-PTX-SLNs were successfully prepared. The cytotoxicity of blank SLNs and siRNA-PTX-SLNs in MCF-7 cells and MCF-7/ADR cells were detected by MTT; and the uptake efficiency of PTX in MCF-7/ADR cells were detected via HPLC method; quantitative real-time PCR and flow cytometry were performed to investigate the silencing effect of siRNA-PTX-SLNs on MDR1 gene in MCF-7/ADR cells. The results showed that PTX loaded SLNs could significantly inhibit the growth of tumor cells, and more importantly, the MDR tumor cells treated with siRNA-PTX-SLNs showed the lowest viability. HPLC study showed that SLNs could enhance the cellular uptake for PTX. Meanwhile, siRNA delivered by SLNs significantly decreased the P-gp expression in MDR tumor cells, thus increased the cellular accumulation of rhodamine123 as a P-gp substrate. In conclusion, the MDR1 gene could be silenced by siRNA-PTX-SLNs, which could promote the growth inhibition efficiency of PTX on tumor cells, leading to synergetic effect on MDR tumor therapy.
Cobalt or chromium alloys are the most common clinical materials of prosthesis and there have been some investigators at home and abroad have done related researches about the genotoxic effects of cobalt and chromium ions and nanoparticles. People have certain understanding about the mechanism of production of ions as well as their influence on cells. However, chromium or cobalt nanoparticles genotoxicity related research is still in its preliminary stage. In each stage, the mechanisms, from creating of the particles, through entering cells, until finally causing genotoxic, are still contained many problems to be solved. This article reviews the research progress in mechanisms of production and genotoxic effects of cobalt, chromium ions and nanoparticles.
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.
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.
Objective To assess the applied significance of carbon nanoparticles in central compartment lymph node dissection in treatment of cN0 papillary thyroid carcinoma. Methods Sixty-eight patients with cN0 papillary thyroid carcinoma who were treated in Tongji Hospital of Tongji Medical College from May. to Oct. in 2012 were randomly allocated to the control group （n=32） and the carbon nanoparticles trace group （tracer group， n=36）， receiving non-carbon nanoparticles trace and carbon nanoparticles trace respectively. All patients were received total resection of thyroid plus the affected side and （or） contralateral side central compartment lymph node dissection. The lymph node-related indexes（including number of dissected lymph node at Ⅵarea and lymph node metastasis rate at Ⅵarea） and operative indexs （including operation time， blood loss， drainage time， complication， and hospital stay） were collected and compared between the 2 groups. Results There were 205 and 324 dissected lymph node at central compartment in control group and tracer group respectively. The results of postoperative pathology showed that the number of lymph node in central compartment of the tracer group was much more than those of control group （8.99±2.24 vs. 6.41±1.56， P＜0.001）. The metastasis rate of central compartment lymph node were 40.6% （13/32） in control group and 47.2% （17/36） in tracer group， but there was no significant difference between the 2 groups （P=0.762）. But in medial area of laryngeal recurrent nerve， the metastasis rate in the tracer group （38.9%， 14/36） was much higher than those of control group （12.5%， 4/32）， P=0.029. There were no significant differences in the operation time， blood loss， drainage time， hospital stay， and complication incidence such as bleeding， temporary hypocalcemia， and injury of superior laryngeal nerve between 2 groups （P＞0.05）. All the patients in 2 groups had followed-up for 6 months without death， recurrence， and metastasis.Conclusions The lymphatic tracer technique of carbon nanoparticles may improve the number of dissected lymph nodes in central region of cN0 papillary thyroid carcinoma， without increasing （or prolonging） operation time， intraoperative blood loss， and postoperative hospital stay， and can accurately represent the metastasis of lymph node， thus to make the staging of the tumor accurately and guide postoperative treatment.
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.
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.
Esophageal cancer is a common malignant tumor of the digestive system, with the characteristics of high incidence and poor prognosis. Traditional treatment methods cannot bring long-term prognosis to patients, and postoperative recurrence and metastasis are also the main causes of treatment failure. With the continuous development of nanomedicine, nanoparticle drug delivery, as a new treatment method, has received extensive attention. The Fe3O4 magnetic nanoparticles due to its unique superparamagnetism and biocompatibility in the treatment of esophageal cancer research in a series of exciting progress has been made. In this paper, the Fe3O4 magnetic nanodrug delivery system for the treatment of esophageal cancer is reviewed.
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.
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.