الملخص
OBJECTIVES@#This study aimed to investigate the effect of new biomimetic micro/nano surfaces on the osteoclastic differentiation of RAW264.7 macrophages by simulating natural osteons for the design of concentric circular structures and modifying graphene oxide (GO).@*METHODS@#The groups were divided into smooth titanium surface group (SS), concentric microgrooved titanium surface group (CMS), and microgroove modified with GO group (GO-CMS). The physicochemical properties of the material surfaces were studied using scanning electron microscopy (SEM), contact-angle measurement, atomic force microscopy, X-ray photoelectron spectroscopy analysis, and Raman spectroscopy. The effect of the modified material surface on the cell biological behavior of RAW264.7 was investigated by cell-activity assay, SEM, and laser confocal microscopy. The effect on the osteoclastic differentiation of macrophages was investiga-ted by tartrate-resistant acid phosphatase (TRAP) immunofluorescence staining and quantitative real-time polymerase chain reaction (qRT-PCR) experiments.@*RESULTS@#Macrophages were arranged in concentric circles along the microgrooves, and after modification with GO, the oxygen-containing groups on the surface of the material increased and hydrophilicity increased. Osteoclasts in the GO-CMS group were small in size and number and had the lowest TRAP expression. Although it promoted the proliferation of macrophages in the GO-CMS group, the expression of osteoclastic differentiation-related genes was lower than that in the SS group, and the difference was statistically significant (P<0.05).@*CONCLUSIONS@#Concentric circular microgrooves restricted the fusion of osteoclasts and the formation of sealing zones. Osteomimetic concentric microgrooves modified with GO inhibited the osteoclastic differentiation of RAW 264.7 macrophages.
الموضوعات
Graphite/pharmacology , Titanium/pharmacology , Haversian System , Macrophages , Cell Differentiation , Oxides/pharmacology , Surface Propertiesالملخص
Objective: To understand the incidence of pneumoconiosis in Ningbo city from 1967 to 2019, and to analyze the distribution characteristics and change trend of pneumoconiosis. Methods: In February 2021, the data of pneumoconiosis patients in Ningbo city from 1967 to 2019 were sorted out. The data from 1967 to 1987 were from historical case files of Zhejiang Center for Disease Control and Prevention, the data from 1988 to 2005 were from the historical case files of Ningbo Center for Disease Control and Prevention, and the data from 2006 to 2019 were from the pneumoconiosis report card in China Disease Prevention and Control Information System; Followed up and supplement relevant information, including basic information, basic information of employers and information related to pneumoconiosis diagnosis, and comprehensively analyze the composition and development trend, population characteristics and industry characteristics of pneumoconiosis. Results: From 1967 to 2019, a total of 1715 cases of pneumoconiosis were reported in Ningbo City, including 1254 cases of stageⅠpneumoconiosis, 258 cases of stageⅡpneumoconiosis, 172 cases of stage Ⅲpneumoconiosis. 1202 cases of silicosis (70.09%) , 296 cases of asbestosis (17.26%) , 40 cases of welder's pneumoconiosis (2.33%) , 32 cases of graphite pneumoconiosis (1.87%) were reported. There were 1296 male cases (75.57%) and 419 female cases (24.43%) were reported. Silicosis (91.15%, 1102/1209) and welder's pneumoconiosis (100.00%, 40/40) were the most common pneumoconiosis in males, while asbestosis (90.24%, 268/297) and graphite pneumoconiosis (87.50%, 28/32) were the most common pneumoconiosis in females. The average age was (49.71±10.90) years old and the average length of service was (10.98±6.96) years. The top three reported pneumoconiosis cases were construction industry (336 cases, 19.59%) , ferrous metal smelting and rolling industry (317 cases, 18.48%) and non-metallic mineral products industry (315 cases, 18.37%) . The top three reported pneumoconiosis cases were 414 cases (24.14%) in Ninghai County, 294 cases (17.14%) in Yuyao City and 272 cases (15.86%) in Yinzhou District. Conclusion: With the development of industries in Ningbo City, government departments should strengthen supervision and management of enterprises involving silica dust and welding fume to curb the high incidence of pneumoconiosis.
الموضوعات
Adult , Female , Humans , Male , Middle Aged , Asbestosis , China/epidemiology , Graphite , Incidence , Pneumoconiosis/epidemiology , Pulmonary Fibrosis , Silicosis/epidemiologyالملخص
Objective: To prepare graphene oxide (GO)-containing gelatin methacrylate anhydride (GelMA) hydrogel and to investigate the effects of in situ photopolymerized GO-GelMA composite hydrogel in wound vascularization of full-thickness skin defect in mice. Methods: The experimental study method was used. The 50 μL of 0.2 mg/mL GO solution was evenly applied onto the conductive gel, and the structure and size of GO were observed under field emission scanning electron microscope after drying. Human skin fibroblasts (HSFs) were divided into 0 μg/mL GO (without GO solution, the same as below) group, 0.1 μg/mL GO group, 1.0 μg/mL GO group, 5.0 μg/mL GO group, and 10.0 μg/mL GO group treated with GO of the corresponding final mass concentration, and the absorbance value was detected using a microplate analyzer after 48 h of culture to reflect the proliferation activity of cells (n=6). HSFs and human umbilical vein vascular endothelial cells (HUVECs) were divided into 0 μg/mL GO group, 0.1 μg/mL GO group, 1.0 μg/mL GO group, and 5.0 μg/mL GO group treated with GO of the corresponding final mass concentration, and the migration rates of HSFs at 24 and 36 h after scratching (n=5) and HUVECs at 12 h after scratching (n=3) were detected by scratch test, and the level of vascular endothelial growth factor (VEGF) secreted by HSFs after 4, 6, and 8 h of culture was detected by enzyme-linked immunosorbent assay method (n=3). The prepared GO-GelMA composite hydrogels containing GO of the corresponding final mass concentration were set as 0 μg/mL GO composite hydrogel group, 0.1 μg/mL GO composite hydrogel group, 1.0 μg/mL GO composite hydrogel group, and 5.0 μg/mL GO composite hydrogel group to observe their properties before and after cross-linking, and to detect the release of GO after soaking with phosphate buffer solution for 3 and 7 d (n=3). The full-thickness skin defect wounds were made on the back of 16 6-week-old female C57BL/6 mice. The mice treated with in situ cross-linked GO-GelMA composite hydrogel containing GO of the corresponding final mass concentration were divided into 0 μg/mL GO composite hydrogel group, 0.1 μg/mL GO composite hydrogel group, 1.0 μg/mL GO composite hydrogel group, and 5.0 μg/mL GO composite hydrogel group according to the random number table, with 4 mice in each group. The general condition of wound was observed and the wound healing rate was calculated on 3, 7, and 14 d of treatment, the wound blood perfusion was detected by laser Doppler flowmetry on 3, 7, and 14 d of treatment and the mean perfusion unit (MPU) ratio was calculated, and the wound vascularization on 7 d of treatment was observed after hematoxylin-eosin staining and the vascular density was calculated (n=3). The wound tissue of mice in 0 μg/mL GO composite hydrogel group and 0.1 μg/mL GO composite hydrogel group on 7 d of treatment was collected to observe the relationship between the distribution of GO and neovascularization by hematoxylin-eosin staining (n=3) and the expression of VEGF by immunohistochemical staining. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and Tukey's method. Results: GO had a multilayered lamellar structure with the width of about 20 μm and the length of about 50 μm. The absorbance value of HSFs in 10.0 μg/mL GO group was significantly lower than that in 0 μg/mL GO group after 48 h of culture (q=7.64, P<0.01). At 24 h after scratching, the migration rates of HSFs were similar in the four groups (P>0.05); at 36 h after scratching, the migration rate of HSFs in 0.1 μg/mL GO group was significantly higher than that in 0 μg/mL GO group, 1.0 μg/mL GO group, and 5.0 μg/mL GO group (with q values of 7.48, 10.81, and 10.20, respectively, P<0.01). At 12 h after scratching, the migration rate of HUVECs in 0.1 μg/mL GO group was significantly higher than that in 0 μg/mL GO group, 1.0 μg/mL GO group, and 5.0 μg/mL GO group (with q values of 7.11, 8.99, and 14.92, respectively, P<0.01), and the migration rate of HUVECs in 5.0 μg/mL GO group was significantly lower than that in 0 μg/mL GO group and 1.0 μg/mL GO group (with q values of 7.81 and 5.33, respectively, P<0.05 or P<0.01 ). At 4 and 6 h of culture, the VEGF expressions of HSFs in the four groups were similar (P>0.05); at 8 h of culture, the VEGF expression of HSFs in 0.1 μg/mL GO group was significantly higher than that in 0 μg/mL GO group and 5.0 μg/mL GO group (with q values of 4.75 and 4.48, respectively, P<0.05). The GO-GelMA composite hydrogels in the four groups were all red liquid before cross-linking, which turned to light yellow gel after cross-linking, with no significant difference in fluidity. The GO in the GO-GelMA composite hydrogel of 0 μg/mL GO composite hydrogel group had no release of GO at all time points; the GO in the GO-GelMA composite hydrogels of the other 3 groups was partially released on 3 d of soaking, and all the GO was released on 7 d of soaking. From 3 to 14 d of treatment, the wounds of mice in the 4 groups were covered with hydrogel dressings, kept moist, and gradually healed. On 3, 7, and 14 d of treatment, the wound healing rates of mice in the four groups were similar (P>0.05). On 3 d of treatment, the MPU ratio of wound of mice in 0.1 μg/mL GO composite hydrogel group was significantly higher than that in 0 μg/mL GO composite hydrogel group, 1.0 μg/mL GO composite hydrogel group, and 5.0 μg/mL GO composite hydrogel group (with q values of 10.70, 11.83, and 10.65, respectively, P<0.05 or P<0.01). On 7 and 14 d of treatment, the MPU ratios of wound of mice in the four groups were similar (P>0.05). The MPU ratio of wound of mice in 0.1 μg/mL GO composite hydrogel group on 7 d of treatment was significantly lower than that on 3 d of treatment (q=14.38, P<0.05), and that on 14 d of treatment was significantly lower than that on 7 d of treatment (q=27.78, P<0.01). On 7 d of treatment, the neovascular density of wound of mice on 7 d of treatment was 120.7±4.1 per 200 times of visual field, which was significantly higher than 61.7±1.3, 77.7±10.2, and 99.0±7.9 per 200 times of visual field in 0 μg/mL GO composite hydrogel group, 1.0 μg/mL GO composite hydrogel group, and 5.0 μg/mL GO composite hydrogel group (with q values of 12.88, 7.79, and 6.70, respectively, P<0.01), and the neovascular density of wound of mice in 1.0 μg/mL GO composite hydrogel group and 5.0 μg/mL GO composite hydrogel group was significantly higher than that in 0 μg/mL GO composite hydrogel group (with q values of 5.10 and 6.19, respectively, P<0.05). On 7 d of treatment, cluster of new blood vessels in wound of mice in 0.1 μg/mL GO composite hydrogel group was significantly more than that in 0 μg/mL GO composite hydrogel group, and the new blood vessels were clustered near the GO; a large amount of VEGF was expressed in wound of mice in 0.1 μg/mL GO composite hydrogel group in the distribution area of GO and new blood vessels. Conclusions: GO with mass concentration lower than 10.0 μg/mL had no adverse effect on proliferation activity of HSFs, and GO of 0.1 μg/mL can promote the migration of HSFs and HUVECs, and can promote the secretion of VEGF in HSFs. In situ photopolymerized of GO-GelMA composite hydrogel dressing can promote the wound neovascularization of full-thickness skin defect in mice and increase wound blood perfusion in the early stage, with GO showing an enrichment effect on angiogenesis, and the mechanism may be related to the role of GO in promoting the secretion of VEGF by wound cells.
الموضوعات
Animals , Female , Humans , Mice , Anhydrides , Endothelial Cells , Eosine Yellowish-(YS) , Gelatin/pharmacology , Graphite , Hematoxylin , Hydrogels/pharmacology , Methacrylates , Mice, Inbred C57BL , Neovascularization, Pathologic , Skin Abnormalities , Vascular Endothelial Growth Factor Aالملخص
Este estudo avalia uma intervenção de oficinas de graffiti, com adolescentes em cumprimento de medida socioeducativa de privação de liberdade em um Centro de Atendimento Socioeducativo de Florianópolis (SC). As oficinas visaram promover uma intervenção artística, espaço de expressão, fortalecimento de vínculos e formação ética-estética-política dos jovens. Foram realizados seis encontros com dois grupos (ala feminina e masculina) de 5 a 15 adolescentes (13 a 18 anos), bem como reuniões com a equipe técnica e os agentes socioeducativos. Posteriormente, foram conduzidos grupos focais com os participantes, sendo realizada análise de conteúdo temática e discussão com registros de diários de campo. Os resultados indicaram contribuição para o caráter socioeducativo da medida, coerente com o Estatuto da Criança e do Adolescente, pois houve opiniões positivas e protagonismo dos adolescentes, reflexões sobre ética e a dinâmica do Centro
This study evaluates an intervention of graffiti workshops with teenagers who had their liberty restricted by socio-educative measures inside a Socio-educative Center in Florianopolis (Brazil). The workshops attempted to promote an artistic intervention, a space for expression, strengthening the bonds and the ethicalesthetical-political growth of the teenagers. Six meetings were made with two groups (the female, and the male ward) with 5 to 15 teenagers (13 to 18 years old), as well as meetings with the technical team and the socio-educative agents. Afterwards, focal groups were conducted with the participants, with analysis of the subject theme and discussions with the field journey being made. The results pointed at contribution for the socio-educative character of the measure, coherent with the Brazilian code for the child and teenager, because there were positive opinions, the teenagers protagonism, as well as reflexions about ethics and the dynamics of the Center.
Este estudio evalúa la intervención de talleres de grafiti con adolescentes que cumplen con una medida socioeducativa de privación de libertad en un Centro de Servicios Socioeducativos de Florianópolis (Brasil). Los talleres tuvieron como objetivo promover una intervención artística, un espacio de expresión, fortalecer los lazos y la formación ética-estética-política de los jóvenes. Se llevaron a cabo seis reuniones con dos grupos (ala femenina y masculina) de 5 a 15 adolescentes (13 a 18 años), así como reuniones con el equipo técnico y los agentes socioeducativos. Posteriormente, se realizaron grupos focales con los participantes, con análisis de contenido temático y discusión con registros de diario de campo. Los resultados indicaron una contribución al carácter socioeducativo de la medida, de acuerdo con el Estatuto brasileño del Niño y el Adolescente, ya que hubo opiniones positivas, protagonismo de los adolescentes, reflexiones sobre la ética y la dinámica del Centro.
الموضوعات
Adolescent , Adolescent , Education , Ethics , Art , Freedom , Graphiteالملخص
Objective: To determine the cytotoxicity and effects of graphene oxide (GO) on cellular proliferation of gingival-fibroblasts, pulp-dental cells and human osteoblasts in culture, and to determine the physical, mechanical and biological properties of poly (methyl methacrylate) (PMMA) enriched with GO. Material and Methods: The GO was characterized with SEM. Cytotoxicity and cell proliferation were determined by the MTT bioassay. The physical mechanical tests (flexural strength and elastic modulus) were carried out with a universal testing machine. Sorption and solubility were determined by weighing before and after drying and immersion in water. Porosity was evaluated by visual inspection. Data were analyzed with Student's t-test and Tukey's posthoc ANOVA. Results: The GO has a heterogeneous morphology and a particle size of 66.67±64.76 µm. GO has a slight to no-cytotoxicity (>50-75% viability) at 1-30 days, and at 24 hours incubation of PMMA with GO significantly stimulates osteoblasts (45±8%, p<0.01). The physical and mechanical properties of PMMA with GO increase considerably without altering sorption, solubility and porosity. Conclusion: GO alone or with PMMA has an acceptable biocompatibility, could contribute to cell proliferation, cell regeneration and improve the physical mechanical properties of PMMA.
Objective: To determine the cytotoxicity and effects of graphene oxide (GO) on cellular proliferation of gingival-fibroblasts, pulpdental cells and human osteoblasts in culture, and to determine the physical, mechanical and biological properties of poly (methyl methacrylate) (PMMA) enriched with GO. Material and Methods: T he G O w as c haracterized with SEM. Cytotoxicity and cell proliferation were determined by the MTT bioassay. The physical-mechanical tests (flexural strength and elastic modulus) were carried out with a universal testing machine. Sorption and solubility were determined by weighing before and after drying and immersion in water. Porosity was evaluated by visual inspection. Data were analyzed with Student's t-test and Tukey's post-hoc ANOVA. Results: The GO has a heterogeneous morphology and a particle size of 66.67±64.76 ?m. GO has a slight to no-cytotoxicity (>50-75% viability) at 1-30 days, and at 24 hours incubation of PMMA with GO significantly stimulates osteoblasts (45±8%, p<0.01). The physical and mechanical properties of PMMA with GO increase considerably without altering sorption, solubility and porosity. Conclusion: GO alone or with PMMA has an acceptable biocompatibility, could contribute to cell proliferation, cell regeneration and improve the physical-mechanical properties of PMMA.
الموضوعات
Humans , Biocompatible Materials , Polymethyl Methacrylate/chemistry , Graphite/chemistry , Osteoblasts , Oxides , Regeneration , Biological Assay , Cell Proliferation , Flexural Strengthالملخص
The biocompatibility of nanomaterials has attracted much attention. Graphene oxide (GO) is a nanomaterial widely used in biomedicine, but its toxicity can not be ignored. In this study, the effect of GO on the blood system (the hemolysis rate, the fragility of erythrocyte, and acetylcholinesterase activity) was systematically investigated. The results showed that the hemolysis rate of erythrocytes was lower than 8% when the GO concentration was below 100 μg/mL (P5 μm (LGO) increased the activity of acetylcholinesterase by 42.67% (P<0.05). Then molecular dynamics simulation was used to study how GO interacted with acetylcholinesterase and increased its activity. The results showed that GO was attached to the cell membrane, thus may provide an electronegative environment that helps the hydrolysate to detach from the active sites more quickly so as to enhance the activity of acetylcholinesterase.
الموضوعات
Acetylcholinesterase , Erythrocytes , Graphite , Nanostructuresالملخص
Atherosclerosis is a chronic inflammatory disease commonly seen in clinical practice. It can lead to thickening of vascular intima, occlusion of lumen stenosis and thrombosis, leading to angina pectoris, hypertension, myocardial infarction and other diseases, posing a serious threat to human life and health. This study provides a method for removing shield needles from graphene oxide thrombus and its preparation. The graphene oxide shield needle mainly includes flexible rotating shaft, radial flexible rod, rotating needle, adsorption main pipe and dosing main pipe, laser measuring device, high definition camera and other structures, which has the following advantages:firstly, it achieves multi-angle rotation grinding thrombosis, precise rotation grinding, avoids vascular damage and infection; secondly, thrombolytic drugs can be applied in the process of rotary grinding and small thrombus can be adsorbed to effectively avoid secondary embolization of blood vessels; thirdly, it a coating of graphene oxide on a rotating needle, which protects against bacteria and infection. This study has practical reference value for the development of thrombotherapy and the application of graphene in the medical field.
الموضوعات
Humans , Adsorption , Graphite , Needles , Thrombosis/prevention & controlالملخص
BACKGROUND: Bioremoval of phenolic compounds using fungi and bacteria has been studied extensively; nevertheless, trinitrophenol bioremediation using modified Oscillatoria cyanobacteria has been barely studied in the literature. RESULTS: Among the effective parameters of bioremediation, algal concentration (3.18 g·L−1 ), trinitrophenol concentration (1301 mg·L−1 ), and reaction time (3.75 d) were screened by statistical analysis. Oscillatoria cyanobacteria were modified by starch/nZVI and starch/graphene oxide in a bubble column bioreactor, and their bioremoval efficiency was investigated. Modifiers, namely, starch/zero-valent iron and starch/GO, increased trinitrophenol bioremoval efficiency by more than 10% and 12%, respectively, as compared to the use of Oscillatoria cyanobacteria alone. Conclusions: It was found that starch/nano zero-valent iron and starch/GO could be applied to improve the removal rate of phenolic compounds from the aqueous solution.
الموضوعات
Picrates/metabolism , Oscillatoria/metabolism , Picrates/analysis , Starch , Biodegradation, Environmental , Bioreactors , Phenolic Compounds/analysis , Metal Nanoparticles , Wastewater , Graphite , Ironالملخص
Abstract The use of antimicrobial agents is an efficient method to prevent dental caries. Also, nanometric antibacterial agents with wide antibacterial spectrum and strong antibacterial effects can be applied for prevention of dental caries. Objectives: The aim of this study was to evaluate the inhibitory effect of reduced graphene oxide-silver nanoparticles (rGO/Ag) composite on the progression of artificial enamel caries in a Streptococcus mutans biofilm model. Material and Methods: Enamel specimens from bovine incisors were divided into eight treatment groups (n = 13), as follows: group 1 was inoculated with S. mutans grown in Brain Heart Infusion containing 1% sucrose (1% BHIS), as negative control; groups 2-4 were inoculated with S. mutans grown in the presence of different rGO/Ag concentrations (0.08, 0.12, 0.16 mg/mL) + 1% BHIS; group 5-7 were inoculated with S. mutans grown in the presence of different agents (0.16 mg/mL reduced graphene oxide, 0.16 mg/mL silver nanoparticles, 10 ppm NaF) + 1% BHIS; group 8 was mixed with 1% BHIS, without inoculation. Artificial enamel carious lesions were produced by S. mutans biofilm model for 7 days. Confocal laser scanning microscopy and atomic force microscopy were used to analyze roughness and morphology of the enamel surface. Polarized light microscopy and confocal laser scanning microscopy were employed to measure the lesion depth and the relative optical density (ROD) of the demineralized layer. Results: Compared with the control groups, the rGO/Ag groups showed: (a) reduced enamel surface roughness; (b) much smoother and less eroded surfaces; (c) shallower lesion depth and less mineral loss. Conclusion: As a novel composite material, rGO/Ag can be a promising antibacterial agent for caries prevention.
الموضوعات
Animals , Cattle , Silver/pharmacology , Streptococcus mutans/drug effects , Dental Caries/prevention & control , Dental Enamel/drug effects , Metal Nanoparticles/chemistry , Graphite/pharmacology , Anti-Bacterial Agents/pharmacology , Reference Values , Silver/chemistry , Surface Properties , Cariostatic Agents/pharmacology , Reproducibility of Results , Microscopy, Confocal , Disease Progression , Dental Caries/microbiology , Dental Enamel/microbiology , Nanocomposites/chemistry , Graphite/chemistryالملخص
In this study,a nano drug delivery system GA-DTX-NGO which could be used for liver tumor photothermal and chemotherapy was prepared and characterized,with docetaxel(DTX) as model drug,glycyrrhetinic acid(GA) as the target molecule,and nano graphene oxide(NGO) as the photosensitizer. Firstly,GA-NGO nanocomposites were synthesized by the amidation reaction,and then GA-DTX-NGO was prepared by ultrasonic dispersion method. The encapsulation efficiency and drug loading ratio were determined by high performance liquid chromatography(HPLC) and ultracentrifugation; the morphology was observed by transmission electron microscopy(TEM). The photothermal conversion test was carried out by laser irradiation at 808 nm and the drug release test in vitro was performed using reverse dialysis. Finally,the effect of GA-DTX-NGO on SMMC-7721 liver tumor cells proliferation was determined by using MTT assay. The results showed that GA-DTX-NGO had good water dispersibility,and TEM results showed a lamellar structure with about 200 nm in diameter. The encapsulation efficiency and drug loading ratio of GA-DTX-NGO were(98. 89 ± 0. 07) % and(64. 74±0. 26) %,respectively. GA-DTX-NGO had strong photothermal conversion performance under 808 nm of laser irradiation. The drug release test in vitro results showed GA-DTX-NGO had obvious sustained-release effects and temperature-dependent release characteristics. The results of cell assay showed that GA-DTX-NGO could effectively inhibit the proliferation of SMMC 7721 cells in a concentration-and time-dependent manner,and the inhibitory effect was enhanced after combination with the near-infrared therapy. In conclusion,the preparation process of GA-DTX-NGO nano drug delivery system is feasible,which could provide some theoretical basis for further study of photothermal and chemotherapy on liver tumor.
الموضوعات
Antineoplastic Agents , Drug Carriers , Drug Delivery Systems , Glycyrrhetinic Acid , Graphiteالملخص
OBJECTIVE@#To evaluate the process characterization of graphene oxide loaded on pure titanium surface and effect on the biological properties of Staphylococcus aureus and osteoblasts.@*METHODS@#Graphene oxide at four concentrations (20, 50, 80, and 100 µg·mL⁻¹) was loaded on the pure titanium surface via electroplating, and the morphology, properties, and hydrophilic properties were measured with a field emission scanning electron microscope, micro Raman spectrometer, and contact angle tester, respectively. In addition, Staphylococcus aureus and osteoblasts were used as models and cultured with pure titanium-graphene oxide. Then, field-emission scanning electron microscopy and laser confocal microscopy were utilized to observe the changes in the amount of bacteria and osteoblast morphology and structure, respectively.@*RESULTS@#Graphene oxide at the four concentrations was successfully loaded on pure titanium surface via electroplating. It improved the hydrophilic properties of pure titanium surface, which benefitted the adhesion and growth of Staphylococcus aureus and changed the morphology and structure of the osteoblasts.@*CONCLUSIONS@#The pure titanium-graphene oxide composite has no antibacterial properties and has good biocompatibility.
الموضوعات
Bacterial Adhesion , Cell Adhesion , Graphite , Microscopy, Electron, Scanning , Osteoblasts , Oxides , Surface Properties , Titaniumالملخص
Brain disease is one of the greatest threats to public health. Brain theranostics is recently taking shape, indicating the treatments of stroke, inflammatory brain disorders, psychiatric diseases, neurodevelopmental disease, and neurodegenerative disease. However, several factors, such as lack of endophenotype classification, blood-brain barrier (BBB), target determination, ignorance of biodistribution after administration, and complex intercellular communication between brain cells, make brain theranostics application difficult, especially when it comes to clinical application. So, a more thorough understanding of each aspect is needed. In this review, we focus on recent studies regarding the role of exosomes in intercellular communication of brain cells, therapeutic effect of graphene quantum dots, transcriptomics/epitranscriptomics approach for target selection, and in vitro/in vivo considerations.
الموضوعات
Blood-Brain Barrier , Brain Diseases , Brain , Classification , Endophenotypes , Exosomes , Graphite , Neurodegenerative Diseases , Public Health , Quantum Dots , Stroke , Theranostic Nanomedicineالملخص
p-Nitrophenylphosphate (PNPP) is usually employed as the substrate for enzyme-linked immunosorbent assays. p-Nitrophenol (PNP), the product of PNPP, with the catalyst alkaline phosphatase (ALP), will passivate an electrode, which limits applications in electrochemical analysis. A novel anti-passivation ink used in the preparation of a graphene/ionic liquid/chitosan composited (rGO/IL/Chi) electrode is proposed to solve the problem. The anti-passivation electrode was fabricated by directly writing the graphene-ionic liquid-chitosan composite on a single-side conductive gold strip. A glassy carbon electrode, a screen-printed electrode, and a graphene-chitosan composite-modified screen-printed electrode were investigated for comparison. Scanning electron microscopy was used to characterize the surface structure of the four different electrodes and cyclic voltammetry was carried out to compare their performance. The results showed that the rGO/IL/Chi electrode had the best performance according to its low peak potential and large peak current. Amperometric responses of the different electrodes to PNP proved that only the rGO/IL/Chi electrode was capable of anti-passivation. The detection of cardiac troponin I was used as a test example for electrochemical immunoassay. Differential pulse voltammetry was performed to detect cardiac troponin I and obtain a calibration curve. The limit of detection was 0.05 ng/ml.
الموضوعات
Electrochemical Techniques/methods , Electrodes , Graphite , Immunoassay/methods , Ink , Microscopy, Electron, Scanning , Troponin I/bloodالملخص
ABSTRACT: Microwaves are an interesting alternative to process dental ceramics. It is well documented that Microwave Hybrid Sintering (MHS) allows important savings in time and energy consumption. However, little is known about its effect on lithium disilicate glass ceramics, a popular material in dentistry today. We analyzed the microstructure of lithium disilicate glass ceramics sintered with MHS compared with conventional sintering. We sintered lithium disilicate glass ceramics using MHS and conventional furnaces, and we analyzed the samples using X-Ray diffraction and SEM. Samples sintered with MHS showed an increased crystalline phase, with an increased number of crystals. These crystals have larger perimeters compared with samples sintered in conventional furnaces. MHS produced a different crystallization pattern and crystal/ matrix ration in lithium disilicate glass ceramics when compared to conventional sintering. This can be associated with the improved mechanical properties of these materials reported previously.
RESUMEN: Las microondas son una interesante alternativa para procesar cerámicas dentales. Está bien documentado que el Sinterizado Híbrido por Microondas (MHS) permite ahorros importantes de tiempo y energía. Sin embargo, poco se ha publicado respecto a sus efectos en cerámicas de disilicato de litio, un material bastante popular en odontología en estos días. En este artículo analizamos la micro estructura de cerámicas de disilicato de litio sinterizada con MHS comparada con el sinterizado convencional. Sinterizamos muestras de cerámicas de disilicato de litio usando MHS y hornos convencionales, y analizamos las muestras usando difracción de rayos X y SEM. Las muestras sintetizadas usando MHS tienen una mayor fase cristalina, con mayor número de cristales. Estos cristales tienen además perímetros mayores, comparados con las muestras sinterizadas en hornos convencionales. MHS produce patrones de cristalización y proporción de cristal/matrix diferentes a las producidos por sinterizado convencional. Esto puede asociarse a las mejoras en propiedades mecánicas reportadas previamente.
الموضوعات
Ceramics/chemistry , Silicates/chemistry , Microwaves , X-Ray Diffraction , Analysis of Variance , Crystallization , Dental Materials/chemistry , Dental Porcelain/therapeutic use , Phase Transition , Graphite/analysisالملخص
Abstract: Pencil core granulomas are still infrequently reported in the literature. A 67-year-old woman presented with a 4mm hard blue subcutaneous nodule on the forehead. She remembered being injured with a pencil tip about 60 years before. The subcutaneous nodule was excised, which microscopically revealed a foreign body reaction with histiocytes containing fragmented coarse black particles. We diagnosed pencil-core granuloma based on the patient's history of pencil tip injury and histological examination findings.
الموضوعات
Humans , Female , Aged , Skin Diseases/pathology , Wounds, Penetrating/complications , Granuloma, Foreign-Body/pathology , Skin Diseases/complications , Granuloma, Foreign-Body/etiology , Graphiteالملخص
Graphene-based approaches have been influential in the design and manipulation of dental implants and tissue regeneration to overcome the problems associated with traditional titanium-based dental implants, such as their low biological affinity. Here, we describe the current progress of graphene-based platforms, which have contributed to major advances for improving cellular functions in in vitro and in vivo applications of dental implants. We also present opinions on the principal challenges and future prospects for new graphene-based platforms for the development of advanced graphene dental implants and tissue regeneration.
الموضوعات
Dental Implants , Graphite , In Vitro Techniques , Regeneration , Titaniumالملخص
Owing to its unique physicochemical properties such as high surface area, notable biocompatibility, robust mechanical strength, high thermal conductivity, and ease of functionalization, 2D-layered graphene has received tremendous attention as a futuristic nanomaterial and its-associated research has been rapidly evolving in a variety of fields.With the remarkable advances of graphene especially in the biomedical realm, in vivo evaluation techniques to examine in vivo behavior of graphene are largely demanded under the hope of clinical translation. Many different types of drugs such as the antisense oligomer and chemotherapeutics require optimal delivery conveyor and graphene is now recognized as a suitable candidate due to its simple and high drug loading property. Termed as ‘ radio-graphene’, radioisotope-labeled graphene approach was recently harnessed in the realm of biomedicine including cancer diagnosis and therapy, contributing to the acquisition of in vivo information for targeted drug delivery. In this review, we highlight current examples for bioapplication of radiolabeled graphene with brief perspectives on future strategies in its extensive bio- or clinical applications.
الموضوعات
Diagnosis , Graphite , Hope , Nanostructures , Theranostic Nanomedicine , Thermal Conductivityالملخص
<p><b>OBJECTIVE</b>To study the effects of graphene quantum dots (GQDs) on hematopoietic system in rats.</p><p><b>METHODS</b>Thirty male SD rats were randomly divided into three groups (n = 10): control group, high dose group (10 mg/kg · d), low dose group (5 mg/kg · d), The rats in experimental group were intravenous injected with GQDs for 28 days and those in control group were injected with normal saline at the same volume. Routine blood and the function of liver and kidney were detected by instrument analysis. The cycle and apoptosis of bone marrow mononuclear cells (BMCs) were detected by FCM. The other three only healthy male SD rat bone marrow mononuclear cells (BMCs) were cultured by joining GQDs for 24 h, 48 h,72 h in vitro, the proliferation was assayed by CCK-8, the content of granulocyte macrophage colony stimulating factor (GM-CSF) from cultural supernatants were detected by ELISA.</p><p><b>RESULTS</b>The amount of red blood cell and concentration of hemoglobin from experimental group were increased significantly compared with those of control groups (P < 0.05), the concentration of triglyceride and high density lipoprotein were decreased. DNA synthesis period was prolonged (P < 0.01), there was no significant difference in apoptosis. BMCs were promoted proliferation clearly after using GQDs for 72 h (P < 0.05). The content of GM-CSF was increased (P < 0.01) .</p><p><b>CONCLUSION</b>GQDs may promote hematopoietic function in rats.</p>
الموضوعات
Animals , Male , Rats , Apoptosis , Bone Marrow Cells , Granulocyte-Macrophage Colony-Stimulating Factor , Metabolism , Graphite , Pharmacology , Hematopoiesis , Quantum Dots , Chemistry , Rats, Sprague-Dawleyالملخص
<p><b>OBJECTIVE</b>To establish the method of graphite furnace atomic absorption spectrometry for the measurement of stannum in urine with calcium nitrate as the matrix modifier.</p><p><b>METHODS</b>Graphite tube was pretreated with calcium nitrate as the matrix modifier, the urine sample was diluted with 1% nitric acid and then direct injection was performed for these samples, and graphite furnace atomic absorption spectrometry was applied for measurement.</p><p><b>RESULTS</b>The concentration of stannum in urine showed a good linear relationship within the range of 8.0~40.0 μg/L, with a correlation coefficient of 0.9981. The minimum detectable concentration was 0.72 μg/L, the degree of precision was 1.54%~6.69%, and the recovery rate was 99.23%~107.63%.</p><p><b>CONCLUSION</b>This method can determine the content of stannum in urine accurately and rapidly, with a high sensitivity and a low cost.</p>