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.
Graphite/pharmacology* ; Titanium/pharmacology* ; Haversian System ; Macrophages ; Cell Differentiation ; Oxides/pharmacology* ; Surface Properties

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.
Adult ; Asbestosis ; China/epidemiology* ; Female ; Graphite ; Humans ; Incidence ; Male ; Middle Aged ; Pneumoconiosis/epidemiology* ; Pulmonary Fibrosis ; Silicosis/epidemiology*

Objective: To establish a graphite furnace atomic absorption spectrometry method for the determination of trace gallium in whole blood. Methods: From January to May 2021, the five factors of ashing temperature, ashing time, atomization temperature, atomization time and matrix modifier concentration in the determination of gallium in whole blood by graphite furnace atomic absorption spectrometry were optimized by using L(16) (4(5)) orthogonal test design. At the same time, within-run, between-run, spiking recovery test and other methodological indicators were tested. Results: Under the optimized detection conditions, the linear range of determination of gallium in whole blood by graphite furnace atomic absorption spectrometry was 0.29-100.00 μg/L (r=0.9991) . The within-run and between-run relative standard deviations (RSD) of repetitive measurement at 10.0, 50.0, 80.0 μg/L concentration levels were 2.3%-4.4% and 1.5%-3.6%, the recovery rate of spiking was 98.1%-103.8%, and the detection limit of the method was 0.13 μg/L. Conclusion: Graphite furnace atomic absorption spectrometry for the determination of trace gallium in whole blood is easy to operate, has a wide linear range, low detection limit, accurate and reliable results, which is suitable for occupational health examinations and the determination of acute gallium poisoning.
Spectrophotometry, Atomic/methods* ; Graphite/chemistry* ; Gallium ; Limit of Detection ; Temperature

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.
Anhydrides ; Animals ; Endothelial Cells ; Eosine Yellowish-(YS) ; Female ; Gelatin/pharmacology* ; Graphite ; Hematoxylin ; Humans ; Hydrogels/pharmacology* ; Methacrylates ; Mice ; Mice, Inbred C57BL ; Neovascularization, Pathologic ; Skin Abnormalities ; Vascular Endothelial Growth Factor A

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 (P<0.01). GO at low concentration levels (<5 μg/mL) had no significant effect on the fragility of erythrocytes, but GO at high concentration (10 μg/mL) increased the fragility of erythrocytes (P=0.01). Moreover, GO increased the activity of acetylcholinesterase on erythrocytes. The concentration of 20 μg/mL graphene oxide with the size >5 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.
Acetylcholinesterase ; Erythrocytes ; Graphite ; Nanostructures

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.
Adsorption ; Graphite ; Humans ; Needles ; Thrombosis/prevention & control*

No abstract available.
Granuloma ; Graphite ; Melanoma

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.
Bacterial Adhesion ; Cell Adhesion ; Graphite ; Microscopy, Electron, Scanning ; Osteoblasts ; Oxides ; Surface Properties ; Titanium

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.
Antineoplastic Agents ; Drug Carriers ; Drug Delivery Systems ; Glycyrrhetinic Acid ; Graphite

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.
Blood-Brain Barrier ; Brain Diseases ; Brain ; Classification ; Endophenotypes ; Exosomes ; Graphite ; Neurodegenerative Diseases ; Public Health ; Quantum Dots ; Stroke ; Theranostic Nanomedicine