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Objective@#To investigate the antibacterial properties, biocompatibility and mechanical properties of Cu-ZnO-loaded dental veneering porcelain to provide an experimental basis for the development of new dental veneering porcelain. @*Methods@#Cu-ZnO nanoparticles were added to IPS E.max Ceram for restorative veneer porcelain at different mass percentages of 0 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, and 6 wt% using ball milling in ceramic powder. A cylindrical specimen with a diameter of 20 mm and a thickness of 2 mm was prepared by high-temperature sintering. Scanning electron microscopy was used to observe the surface morphologies of nano-Cu-ZnO and the specimens. The antibacterial effect of Escherichia coli (E. coli) was quantitatively studied by the plate colony counting method. The CCK-8 method was used to evaluate in vitro the cytotoxicity of the tested piece to mouse fibroblasts (L929). Live and dead cells were observed by fluorescence microscopy. The mechanical properties of modified IPS E. Max Ceram veneering porcelain were tested by a three-point bending strength test. @* Results @# Under the scanning electron microscope, Cu-ZnO appears with a block-like structure and can be seen dispersed in the veneering porcelain. When the nano Cu-ZnO loading was 1 wt%, 2 wt%, 3 wt%, and 4 wt%, the antibacterial rates of the specimens were 24.85%, 67.94%, 96.92%, and 99.99%, respectively, and the difference between the experimental groups and the control group was statistically significant (F = 23.308,P = 0.001). The relative growth rate of each group was greater than 80% after coculture with mouse fibroblast cells (L929) for 1 day and 3 days, and there was no significant difference between the groups. The morphology of L929 cells was normal after coculture for 24 hours. With the increase in the Cu-ZnO concentration, the flexural strength of the specimen exhibited an increasing trend followed by a decreasing trend. The bending strength of the specimen loaded with 3 wt% nano Cu-ZnO reached the maximum value (84.728 ± 6.82) MPa, and there was no statistically significant difference between groups (F = 0.633,P = 0.702).@*Conclusion@#The antibacterial rate of IPS E. max Ceram veneering porcelain loaded with 3 wt% nano Cu-ZnO was more than 96% against E. coli after high-temperature sintering at 750 ℃. The bending strength reached the maximum (84.728 ± 6.82) MPa, and there was no obvious cytotoxicity.
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Object:To investigate the impact of carbon nanoparticle tracing on the number of lymph nodes harvested in obese patients during radical gastrectomy for gastric cancer.Methods:Clinical data of 127 patients undergoing D 2 radical gastrectomy in the Affiliated Tumor Hospital of Zhengzhou University from Jan 2015 to Dec 2019 were retrospectively analyzed. According to whether the patients were injected with carbon nano particles during operation, they were divided into two groups: 64 patients without carbon nano particles during operation served as control group; 63 patients with carbon nano particles were included into experimental group. Results:The operation time of the control group was (160±31) min and that of the experimental group was (168±28) min ( t=-1.521, P=0.445). Intraoperative blood lose in the control group was (234±82) ml and that in the experimental group was (238±84) ml ( t=-0.295, P=0.846). The number of lymph nodes harvested in the first station, in the second station, the number of total lymph nodes and the number of lymph nodes with diameter <5 mm in the control group were less than those in the experimental group(10.4±3.8 vs. 24.5±10.6, t=-10.054),(6.6±2.8 vs. 16.8±7.3, t=-10.381),(17.1±6.4 vs. 41.2±17.6, t=-10.293),(3.9±2.5 vs. 21.2±9.1, t=-14.662) (all P<0.05), while the number of positive lymph nodes was not statistically different between the two groups all (5.9±6.2 vs. 4.2±3.4, t=-1.963, P>0.05). Black staining of lymph nodes in nano carbon group: 1 542 black stained lymph nodes were detected in the experimental group, the black staining rate of lymph nodes was 59.44% (1 542/2 594). Conclusion:Intraoperative application of carbon nanoparticles can significantly increase the number of harvested lymph nodes in obese (BMI≥25 kg/m 2) gastric cancer patients after radical resection.
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Internal contamination of radionuclides in the event of nuclear emergencies can lead to serious harm to human health. The research and development of radionuclide chelating agents and the application of new technologies can reduce the internal damage caused by radionuclides. Compared with traditional preparations, the nano-preparations have the advantages of improving drug dissolution, targeting and positioning drug release, and easily passing through biofilm barrier. In recent years, many scholars have used different nano-preparation forms for different decorporation drugs, including nanoparticles, nano-liposomes, nano-emulsions, etc., to conduct related research in order to achieve better clinical application effects. Nanomaterials with excellent properties have the advantages of high efficiency, rapid adsorption and high biocompatibility, etc., and have been used more and more widely in radionuclide decorporation. In this paper, combined with the relevant literatures at home and abroad, the internal contamination of radionuclides is classified according to nuclide-deposited sites of tissues and organs, and the applications of related nanoformulations and nanomaterials in radionuclide decorporation are introduced in order to provide reference for further research.
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@#Nanomaterials usually refer to tiny particles with a diameter of 1-100 nm, which often have unique physicochemical properties and are one of the main areas of research interest for development of dental biomaterials. Nano-calcium phosphate modified dental materials have been widely used in pit and fissure sealing, dental resin restoration, tooth adhesion, and root canal sealing. The current research shows that the dental material modified by nano-calcium phosphate has stronger mechanical properties and shows long-term calcium and phosphorus ion release and excellent ion recharging ability, which can promote the remineralization of tooth hard tissue and has good prospects for application. However, it is difficult to accurately simulate the complex environment of the oral cavity. Therefore, the biocompatibility, cytotoxicity and effect of clinical application of nano-calcium phosphate modified dental materials still needs further study. This review summarizes and discusses the recent research progress regarding nano-calcium phosphate modified dental materials in the prevention and treatment of dental pulp diseases.
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BACKGROUND: Some studies have shown that topical application of zoledronic acid and topical application of silver nanoparticles can promote bone formation, but the difference between two methods has not been reported. OBJECTIVE: To investigate the effect of topical application of zoledronic acid versus topical application of silver nanoparticles on rabbit tooth extraction socket immediate implantation of titanium screw bonding. METHODS: Twenty-four New Zealand white rabbits were randomly divided into zoledronic acid and silver nanoparticles groups (n=12/group). After removing four incisors of the upper and lower jaws, the mixture of nanometer silver and nanometer hydroxyapatite and nanometer zoledronic acid hydroxyapatite were respectively filled in the tooth extraction pit of the two groups, and titanium screw was implanted at the same time. The isolated specimens of the upper and lower mandibles were taken at 4, 8 and 12 weeks after surgery. The data reflecting the osseointegration around the implant were obtained through gross observation, torque test, bone density test and histomorphological observation. The study was approved by the Ethical Committee of the Third Hospital of Hebei Medical University in December 2015, approval No. Z2015-021-1. RESULTS AND CONCLUSION: (1) The test results of torque mechanics showed that the average torque peak value of all titanium nails increased with the extension of time (the average value of torque peak value) and reached the maximum value at 12 weeks (the average value of torque peak value). At 4, 8 and 12 weeks after surgery, the torque peak value of titanium screw in the zoledronic acid group was higher than that in the silver nanoparticles group, and the stability of titanium screw in zoledronic acid group was better than that in silver nanoparticles group, but the difference was insignificant (P>0.05). (2) General observation and histological observation showed that at 4, 8 and 12 weeks after surgery, the hardness and structure of bone around the implants in the zoledronic acid group were significantly better than those in the silver nanoparticles group. (3) Bone mineral density analysis results showed that, at 4, 8 and 12 weeks after surgery, the gray value of bone tissue around the titanium screw in the zoledronic acid group was higher than that in the silver nanoparticles group at the same period (P>0.05). (4) These results suggest that the osseointegration of immediate implantation using nanometer zoledronic acid hydroxyapatite is better than that of the mixture of nanometer silver and nanometer hydroxyapatite.
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BACKGROUND: In the scheme of titanium surface modification and coating modification, the drug sustained-release system constructed by surface nanotube modification and hydroxyapatite coating modification has broad clinical application prospects. OBJECTIVE: To construct composite drug loading coating of titanium dioxide nanotube/hydroxyapatite loaded with vancomycin hydrochloride, and analyze the drug release performance and cytotoxicity of the composite coating in vitro. METHODS: A two-step anodic oxidation method was used to construct titanium dioxide nanotubes on the titanium surface, and the prepared hydroxyapatite was loaded on the surface of the nanotubes by electrophoretic deposition, so as to obtain a nanotube/hydroxyapatite composite coating structure. Subsequently, the composite coating was used as a drug-loaded platform, and vancomycin hydrochloride was loaded by physical adsorption to finally obtain a composite drug-loaded coating. The in vitro drug release properties of hydroxyapatite/vancomycin hydrochloride, titanium dioxide nanotubes/vancomycin hydrochloride, titanium dioxide nanotubes/hydroxyapatite/vancomycin hydrochloride coating were measured. Human osteoblasts were cultured with titanium dioxide nanotubes/hydroxyapatite/vancomycin hydrochloride coating extracts of different concentrations. MTT assay was used to detect cytotoxicity. Human osteoblasts were inoculated on the surface of hydroxyapatite, titanium dioxide nanotubes, titanium dioxide nanotubes/hydroxyapatite/vancomycin hydrochloride, and the changes of cell morphology were observed. RESULTS AND CONCLUSION: (1) Compared with hydroxyapatite/vancomycin hydrochloride, titanium dioxide nanotube/vancomycin hydrochloride coating, titanium dioxide nanotube/hydroxyapatite/vancomycin hydrochloride coating had a longer drug sustained-release effect. The release time exceeded 150 hours. (2) The 10%, 50%, and 100% concentration of titanium dioxide nanotubes/hydroxyapatite/vancomycin hydrochloride coating extract had no obvious cytotoxicity. The relative activity of osteoblasts was more than 70%. (3) The osteoblasts on the three kinds of coating surface grow well; the cytoskeleton was intact; and the nucleus-cytoplasm ratio of the cells was normal, which was not significantly different from the morphology of the cells in pure culture. (4) The results show that the coating of titanium dioxide nanotubes/hydroxyapatite/vancomycin hydrochloride has good drug release properties in vitro without obvious cytotoxicity.
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OBJECTIVE: To study the effect of nano-cerium oxide on the early development of zebrafish embryos. METHODS: The well-developed zebrafish embryos were randomly divided into the control group and the 50, 100, 200, 400 and 800 mg/L dose groups, with 40 embryos in each group. The dose groups were treated with nano-cerium oxide at the corresponding mass concentration for 5 days. The control group received no treatment. The death and malformation of embryos were observed. The heart rate of zebrafish embryos was recorded using confocol microscope. The protein expression of microtubule-associated protein 1 light chain 3(LC3) and cleaved Caspase-3 and were observed by Western blot technology. RESULTS: The death and embryonic malformation rate of zebrafish embryos increased with the increase of doses, showing statistical significance(P<0.01). The heart rate of the 800 mg/L dose group was decreased compared with the control group [(77±8) vs(93±4) beats/min, P<0.01]. There was no statistical significant difference in LC3-Ⅱ protein expression in each groups(P>0.05). The cleaved Caspase-3 protein expression increased in all dose groups compared with the control group(P<0.05). The cleaved Caspase-3 protein expression in the 200 mg/L dose group was higher than that in the 50 mg/L dose group(P<0.05). CONCLUSION: The nano-cerium oxide may induce cell apoptosis, causing toxic effect in early development of zebrafish embryos.
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OBJECTIVE: To prepare amphotericin B vaginal nanosuspension foam and study the physicochemical properties and in vivo pharmacodynamics. METHODS: Using the single factor method, the concentration of egg lecithin and the technical parameters of foaming agent in formulation were gradually optimized. Then, the physicochemical properties, including drug particle size, appearance of foam and formed capability, were studied. The therapeutic effect on vaginal inflammatory infection was investigated with the mouse model of Candida albicans vaginitis. RESULTS: The optimal formulation of amphotericin B nanosuspension foam included 5 mg•mL-1 amphotericin B, 60 mg•mL-1 egg lecithin and 30 mg•mL-1 APG0810. The drug particle size, range of micro-foam diameter and foam half-life were about 240 nm, 200-400 μm and 43.5 min, respectively. It was found that amphotericin B nanosuspension vaginal foam had significant therapeutic effect on mouse vaginal inflammation infection. CONCLUSION: The amphotericin B nanosuspension foam has good physicochemical properties and excellent pharmacological activity in vivo, which shows potential use for the therapy of vulvovaginal candidiasis.
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The treatment of triple-negative breast cancer with highly malignant tumors is limited by the formation of drug-resistant clones of cancer cells and the severe toxicity of conventional chemother- A peutic drugs to normal tissue. Recent studies have shown that in the comprehensive targeted therapy of triple-negative breast cancer not only nano-drug delivery systems, with their unique physical and chemical properties of nanomaterials, can load chemotherapeutic drugs, active gene fragments and immunopotentiator, but also attenuate the effects of chemotherapeutic drugs, inhibit gene proliferation and stimulate the immune system by means of photothermal ablation. So that cancer cells are inhibited and killed. The nano-delivery system has changed the pharmacokinetic characteristics of conventional chemotherapeutic drugs and significantly reduced adverse drug reactions. This article reviews the progress in nano-delivery systems in the comprehensive targeted therapy of triple-negative breast cancer.
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Objective@#To establish a nanometer magnetic particle chemiluminescence methodfor the detection of specific IgE antibodies to Tyrophagus putrefaciens allergen.@*Methods@#According to the routine operation steps of chemiluminescence, chemiluminescence reaction system and suitable immune reaction conditions for detection of specific IgE of Tyrophagus putrescentiae allergen are established. Considering the performance of the chemiluminescence method established in this paper, the American Somerfly Phadia method wasused as the gold standard to evaluate the test performance of the established chemiluminescence method.@*Results@#In thechemiluminescence reaction system, Luminol concentration in luminescent substrate A solution is 0.4 mg/ml, Urea hydrogen peroxidein luminescent substrate B solutionis 0.2 mg/ml.The sensitivity of this luminescent reaction system to horseradish peroxidase (HRP) is very high, the minimum detectable HRP is 0.01 ng/ml.In the immune response, the room temperature light-shielding reaction was detected for 5 min after the addition of substrates A and B, and the detection values were effective within 5-30 min. 37 ℃ is optimum luminescence reaction temperature. Choose the range of 0.35-100 IU/ml as the standard curve. According to the results of 120 clinical trials, using Phadia (immunofluorescence method) as the gold standard, the chemiluminescence method established in this study has significant significance for the detection of Tyrophagus putrescentiae allergen.@*Conclusion@#A nanometer magnetic particle chemiluminescence method was successfully established for the detection of specific IgE antibodies to Tyrophagus putrescentiae allergen.
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Objective To establish a nanometer magnetic particle chemiluminescence methodfor the detection of specific IgE antibodies to Tyrophagus putrefaciens allergen.Methods According to the routine operation steps of chemiluminescence, chemiluminescence reaction system and suitable immune reaction conditions for detection of specific IgE of Tyrophagus putrescentiae allergen are established. Considering the performance of the chemiluminescence method established in this paper, the American Somerfly Phadia method wasused as the gold standard to evaluate the test performance of the established chemiluminescence method. Results In thechemiluminescence reaction system, Luminol concentration in luminescent substrate A solution is 0.4 mg/ml, Urea hydrogen peroxidein luminescent substrate B solutionis 0.2 mg/ml.The sensitivity of this luminescent reaction system to horseradish peroxidase (HRP) is very high, the minimum detectable HRP is 0.01 ng/ml. In the immune response, the room temperature light-shielding reaction was detected for 5 min after the addition of substrates A and B, and the detection values were effective within 5-30 min. 37 ℃ is optimum luminescence reaction temperature. Choose the range of 0.35-100 IU/ml as the standard curve. According to the results of 120 clinical trials, using Phadia (immunofluorescence method) as the gold standard, the chemiluminescence method established in this study has significant significance for the detection of Tyrophagus putrescentiae allergen.Conclusion A nanometer magnetic particle chemiluminescence method was successfully established for the detection of specific IgE antibodies to Tyrophagus putrescentiae allergen.
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Objective To explore the clinical application value of carbon nanoparticles labeled lymph node staining combined with artery approach in radical resection of sigmoid colon cancer.Methods The retrospective cohort study was conducted.The clinicopathological data of 40 patients with sigmoid colon cancer who were admitted to the Tumor Hospital of Zhengzhou University (Henan Cancer Hospital) from December 2015 to June 2016 were collected.Among 40 patients undergoing radical resection of sigmoid colon cancer,20 using nanometer carbon lymph node staining combined with artery approach and 20 using the traditional lymph node sorting were respectively allocated into the observation group and control group.Observation indicators:(1) detection of the lymph node and pathological examination;(2) follow-up situations.Follow-up using outpatient examination and telephone interview was performed to detect adjuvant chemotherapy,tumor recurrence or metastasis and surgery-related complications up to June,2017.Measurement data with normal distribution were represented as (x)±s,and comparisons between groups were evaluated with the t test.Comparisons of count data were analyzed using the chi-square test.The comparisons of ordinal data were analyzed using the nonparametric test.Results (1) Detection of the lymph node and pathological examination:40 patients underwent successful radical resection of sigmoid colon cancer.The lymph node sorting time,total and average numbers of lymph node sorting,total and average numbers of lymph node with diameter ＜ 5 mm,cases with lymph node number ＜ 12 and numbers of the first,second and third stations lymph nodes were respectively (13.1±2.4) minutes,522,28.0±7.0,152,8.6±2.5,0,13.7±3.6,9.5±2.5,4.7±1.2 in the observation group and (18.4±3.5) minutes,239,13.0±3.0,64,3.9± 1.7,6,6.1 ± 1.6,6.6± 2.2,2.5± 1.0 in the control group,with statistically significant differences between groups (t =14.562,24.872,19.256,x2 =4.902,t =14.368,10.026,8.210,P＜0.05).The total number of positive lymph node,positive rate of lymph node,metastasis rate of patients,total and average numbers of positive lymph node with diameter ＜ 5 mm and numbers of the first,second and third stations positive lymph nodes were respectively 82,0.22％±0.13％,17/20,51,3.9± 1.9,4.2± 1.8,1.9±0.6,2.3± 1.2 in the observation group and 43,0.48％±0.18％,7/20,38,2.7±1.5,2.1±0.6,2.6±0.7,1.4±0.5 in the control group,showing no statistically significant difference in the positive rate of lymph node and number of the third station positive lymph nodes between groups (t =1.462,1.759,P＞0.05).There were statistically significant differences in the metastasis rate of patients,average number of positive lymph nodes with diameter ＜ 5 mm and numbers of the first and second stations positive lymph nodes between groups (x2 =10.417,t =7.264,4.682,3.410,P＜0.05).(2) Follow-up situations:40 patients were followed up for 12-18 months,with a median time of 16 months.Eighteen and 10 patients in the observation group and control group received postoperative adjuvant chemotherapy,showing a statistically significant difference between groups (x2=5.833,P＜ 0.05).Tumor recurrence or metastasis was respectively detected in 0 and 2 patients (1 with local recurrence and 1 with liver metastasis) in the observation group and control group,with no statistically significant difference between groups (x2=2.105,P＞ 0.05).During the follow-up,there was no surgery-related complication.Conclusion The carbon nanoparticles labeled lymph node staining combined with artery approach in radical resection of sigmoid colon cancer can increase the sorting rate and number of lymph node,and improve the accuracy of postoperative pathological staging.
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Objective To use the liquid protein combined with MALDI-TOF-MS for screening the serum differential peptides markers in lung adenocarcinoma patients and to establish the lung adenocarcinoma diag-nosed prediction model for founding the potential markers for the diagnosis of lung adenocarcinoma.Methods 37 patients with lung adenocarcinoma and 33 healthy subjects and benign lung disease which were made up in control group were collected,in the two groups the age and the sex were matched.The two groups were ran-domly divided into training group(30 cases of lung adenocarcinoma,26 cases of control)and test group(7 ca-ses of lung adenocarcinoma,7 cases of control)according to 3:1.T he differential diagnosis of lung adenocarci-noma and control group was performed by liquid chip-time-of-flight mass spectrometry and software ClinPro-Tools 3.0 to establish a prediction model of lung adenocarcinoma.The diagnostic model was validated by using serum samples from the test group to assess the diagnostic efficacy of the model.Results Nine peptide peaks with significant differences(P<0.05)were obtained by ClinProTools 3.0 software analysis.The up-regulated peaks in lung adenocarcinoma(m/z)were 8 976.5,4 469.05,4 966.78,8 925.5,4 531.05,and the down-reg-ulated m/z were 3 304.44,8 594.76,3 266.82,3 195.52.According to the genetic algorithm(GA),the lung ad-enocarcinoma diagnosis and prediction model was established.The overall recognition ability of the model was 94.49%.The model was evaluated by the test group.The results showed that the sensitivity of the model was 100.0% and the specificity was 85.7%.Conclusion Among lung adenocarcinoma patients,serum benign lung disease and healthy,there are differences in the serum peptide.T he use of differential peptide peaks to estab-lish lung adenocarcinoma diagnostic prediction model for the early diagnosis of lung adenocarcinoma provides a new method.
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Objective: To prepare nano polypyrrole (PPy)/chitin composite membrane and observe their biocompatibility. Methods: The nano PPy was synthesized by microemulsion polymerization, blended with chitosan and then formed membranes. The membranes were then modified by acetylation to get the experimental membranes (nano PPy/chitin composite membranes, group A). The chitosan membranes (group B) and chitin ones (group C) modified by acetylation acted as control. Scanning electron microscopy and FT-IR spectra were used to identify the nano PPy and the membranes of each group. And the conductivity of membranes of each group was measured. Schwann cells were co-cultured in vitro with each group membranes to observe the biocompatibility by inverted microscope observing, living cell staining, cell counting, and immunofluorescence staining. The lysozyme solution was used to evaluate the degradation of the membranes in vitro. Results: The FT-IR spectra showed that the characteristic vibrational absorption peaks of C=C from nano PPy appeared at 1 543.4 cm -1 and 1 458.4 cm -1. Scanning electron microscopy observation revealed that the size of nano PPy particles was about 100-200 nm. The nano PPy particles were synthesized. It was successful to turn chitosan to chitin by the acetylation, which was investigated by FT-IR analysis of membranes in groups A and C. The characteristic peaks of the amide Ⅱ band around 1 562 cm -1 appeared after acetylated modification. Conductivity test showed that the conductivity of membranes in group A was about (1.259 2±0.005 7)×10 -3 S/cm, while the conductivity of the membranes in groups B and C was not detected. The nano PPy particles uniformly distributed on the surface of membranes in group A were observed by scanning electron microscope; the membranes in control groups were smooth. As a result, the nano PPy/chitin composite membranes with electrical conductivity were obtained. The cultured Schwann cells were found to survive with good function by fluorescein diacetate live cell staining, soluble protein-100 immunofluorescence staining, and inverted microscope observing. The cell counting showed that the proliferation of Schwann cells after 2 days and 4 days of group A was more than that of the two control groups, and the differences were significant ( P<0.05). It indicated that the nano PPy/chitin composite membranes had better ability of adhesion and proliferation than those of chitosan and chitin membranes. The degradation of membranes in vitro showed that the degradation rates of membranes in groups A and C were significantly higher than those in group B at all time points ( P<0.05). In a word, the degradation performance of the membranes modified by acetylation was better than that of chitosan membranes under the same condition. Conclusion: The nano PPy and chitosan can be blended and modified by acetylation successfully. Nano PPy/chitin composite membranes had electrical conductivity, degradability, and good biocompatibility in vitro.
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Objective: To detect the optimal fusing temperature, the fusing time and the best filler ratio of α-Si3N4 and SP1SiO2, and to clarify their influence in the properities of dental resin composites. Methods: The α-Si3N4 crystalline were mixed with SP1SiO2 particle at the ratio of5:l (Wt%), and then were sintered under 500°C, 650°C, 800°C, 950°C and 1 100°C at a rise rate of 250 · h-1 and maintained for 10 min, 30 min and 3 h, respectively (used as α-Si3N4-SP1SiO2 groups). SP1SiO2 particle, α-Si3N4 crystalline, mixed and non-fused α-Si3N4 and SP1SiO2 (mixed) groups were set up, and two commercially available resin composites were selected and used as control groups. And they were fully mixed with the resin matrix in 60% (Wt%) after the treatment of cyclohexane solution to make the samples. The flexural strength of specimen was tested and the morphology of section under SEM was analyzed. Then α-Si3N4 was mixed with SP1SiO2 in a ratio of 2; 1. It was fused under the optimal fusing conditions. After the treatment of cyclohexane solution, it was mixed and polymerized with the resin matrix in the proportions of 20%, 40%, 60%, 70% and 75% (Wt%), and two kinds of commercially available resin composites were selected and used as control groups. The flexural strength of specimens was tested and the morphology of section under SEM was analyzed. Results: The maximum flexural strength value in α-Si3N1-SP1SiO2 groups was at 800°C and 30 min (P>0. 05); the flexural strength value was significantly higher than those in SP1SiO2 group, α-Si3N1 crystalline group, mixed group and two control groups (P<0. 05), and the morphology of section SEM was consistent with the mechanical properties. The flexural strengths of resin composites were increased gradually with the increasing of filler ratios of α-Si3N4 and SP1SiO2 fusion from 20% to 60% (P<0. 05); the flexural strength values of resin composites with the proportion of 60%-70% were not increased significantly, the flexural strength values of resin composites with the proportion of 70%-75% were decreased, and the flexural strength values of the resin composites with the proportion of 60% and 70% were significantly higher than those of resin composites with the proportions of 20%, 40%, 75% and control groups; the morphology of section under SEM was consistent with the mechanical properties. Conclusion: The optimum fusing condition for α-Si3N4 and SP1SiO2 is 800°C for 30 min, and the best filler ratio of α-Si3N4 and SP1SiO2 is 70%.
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Objective To evaluate a novel lymph node (LN) sorting method on surgical resected sample guided by nanometer carbon staining and principle following the supplying artery tributory in rightsided colon carcinoma.Methods From May 2015 to June 2016,51 patients were randomly divided into two groups adopting traditional LN sorting method and that of a combination of nanometer carbon and artery guided.The final LN status were compared between the 2 groups.Results The total LN number and the positive LN in novel method group were higher than control group (437 vs.349,70 vs.54).The dissection time used,the number of harvested positive LN that was ＜ 5 mm were significantly different [(13.1 ± 3.2) minvs.(17.8 ±3.8)min,t=4.75,P=0.000;1.0±l.0vs.0.2 ±0.6,t=3.51,P=0.000].The number of patients with harvested LN less than 12,the rate of positive lymph nodes,the rate of metastasis were not significantly different (all P ＞ 0.05) between the two groups.Conclusions Use of nanometer carbon development combined with artery approach facilitates LN sorting,yielding more positive LNs,and increating the accuracy of pathological staging in right-sided colon cancer.
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Objective:To study the attachment and collagen deposition of human gingival firbroblasts (HGFs) on titanium surface with different topography.Methods:Titanium surfaces created by machining(group M),electrolytic etching(group ECE) and electrolytic etching and acid etching(group ECA) were observed by SEM.HGFs cultured on the titanium surfaces were observed by laser scanning confocal microscope.Attachment of the cells was examined by comparing the numbers of attached to detached cells,respectively.Collagen production and deposition were examined via a Sirius red-based stain assay and confocal laser scaning microscopy.Results:The surface rouphness (μm) of group M,ECE and ECA was 0.867 5 ± 0.136 8,1.749 8 ± 0.355 1 and 1.671 4 ± 0.297 0 (P＜ 0.05) respectively,Cell attachment was significantly weaker on machined surface than on ECE and ECA surfaces,while which was weaker on ECE surface than on ECA surface.Collagen production was the highest on the machined surface,followed by that on ECE and ECA surface,Collagen deposition displayed a parallel pattern on the machined surface,while it was multidirectional on the ECE and ECA surfaces.Conclusion:The ECA surface of titanium may be beneficial to HGFs attachment,the machined surface may promote collagen deposition.
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Nanometer zinc oxide (Nano-ZnO) has been widely applied in many fields such as rubber,ceramics,textile,cosmetics,etc.due to its excellent physical,chemical and biological properties.In recent years,its applications in biomedicine have been paid more and more attention.This paper introduces the unique optical,chemical,mechanical,semi-conducting and biological properties of Nano-ZnO.Meanwhile,the applications of Nano-ZnO in bio-sensing and detection,biological nutrition,medical treatment,biological imaging,drug delivery,tumor cells targeted killing and translational medicine are also reviewed,and the brief outlook on the applications is presented.
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Objective To know the effect of nanometer titanium dioxide (nano -TiO2 )on the oxidative stress in zebrafish. Methods A total of 64 zebrafishes were randomly divided into 4 groups with different concentrations of nano -TiO2 exposure,which including control group,low dose group (2 mg/L),moderate dose group (8 mg/L)and high dose group (32 mg/L).The content of MDA,the activities of SOD and ATPase in gill,liver and muscle were measured in 1 0 zebrafishes in each group after 30 d exposure.Histopathological changes of gill,liver and muscle in the remainder fishes were observed.Results The content of Malondialdehyde (MDA)in the fish gill of the moderate and high dose group were significantly higher than that of the control group (P <0.05).The activity of Superoxide dismutase (SOD)in the fish gill of the high dose group was significantly increased compared with the control group (P <0.05).The activities of Adenosine triphosphatase(ATPase)in the fish gill of the moderate and high dose group were significantly decreased compared with the control group (P <0.05).The changes on the content of MDA and the activities of SOD in the fish liver were similar with that in the fish gill after nano -TiO2 exposure,while there was no significant change in the activity of ATPase of the fish liver.And no significant changes were observed in the content of MDA,the activities of SOD and ATPase in the fish muscle (P >0.05 ). Histopathological observation showed infiltration by inflammatory cells, swelling and degeneration, vacuolation and necrosis in zebrafish gill and liver with different degrees.Conclusion Nano -TiO2 exposure could induce the oxidative stress in zebrafish,causing pathological changes in the fish gill and liver.
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Objective:To observe the effects of aging performance on the property of dental zirconia sintered by microwave furnace and conventional furnace.Methods:48 zirconia wafer specimens were fabricated and randomly divided equally into 2 groups.The samples were sintered in a microwave furnace(Mgroup)and a conventional furnace(C group)respectively.The samples from the 2 groups were divided into 2 sub-groups and treated by room temperature and dry condition(A group)and 1 34 ℃ with 0.2 MPa pres-sure(B group,accelerated aging)respectively.The m phase fraction of the samples was determined by X-ray diffraction analysis.The biaxial flexural strength was examined by universal testing machine.The fracture cross section was observed by SEM.Results:CB and MB groups showed higher m phase fraction than CA and MA groups(P 0.05).Conclusion:The aging perform-ance of zircinia sintered by microwave method were similar to that sintered by conventional method.