ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Liuwei dihuang pills is a famous Traditional Chinese Medicine with various anti-cancer properties. Over 50 pharmaceutical manufacturers produce Liuwei dihuang pills in China and an estimated millions of people around the world orally take it every day. D-glucaro-1,4-lactone (1,4-GL) was quantified to be about 12.0 mg/g in Liuwei dihuang pills and a primary bioactive component of it inhibiting the activity of ß-glucuronidase in vivo. 1,4-GL can prevent and effectively inhibit various types of cancer. However, its exact mechanism of action remains unknown. The study would justify the traditional usage of Liuwei dihuang pills against cancers. AIM OF THE STUDY: 1,4-GL, a bioactive ingredient derived from Liuwei dihuang pills, a famous Traditional Chinese Medicine, could delay the progression of diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) in rats. The mechanism underpinning the effect, however, remains poorly understood. MATERIALS AND METHODS: Healthy and HCC rats were treated with or without 1,4-GL (40.0 mg/kg) and 1HNMR-based metabonomic analysis was employed. 10 metabolites in uric acid pathway were quantitatively determined by UPLC-MS/MS. The expression of xanthine dehydrogenase (XDH), SLC2A9 mRNA, and SLC2A9 protein was determined using RT-qPCR and Western Blot. The effect of 1,4-GL on HCC-LM3 cells was verified in vitro. The alterations of ROS activity, SLC2A9 and XDH gene levels were observed in NCTC-1469 cells induced by lipopolysaccharide (LPS) after 1,4-GL treatment. RESULTS: After the intervention of 1,4-GL, improved pathological morphology, liver lesions in HCC rats was observed with restored serum levels of AFP, AST, ALP, γ-GGT and Fisher's ratio. Hepatic metabonomics revealed that puring metabolism were significantly regulated by 1,4-GL in HCC rats. Uric acid, xanthine and hypoxanthine levels were quantified by UPLC-MS/MS and found to be nearly restored to control levels after 1,4-GL treatment in HCC rats. Changes in xanthine oxidase activity, XDH mRNA expression, and SLC2A9 mRNA and protein expression were also reversed. 1,4-GL treatment in LM3 HCC cells were consistent with the results in vivo. Furthermore, oxidative stress indicators such as T-SOD, GSH, CAT and MDA in serum and liver were improved after HCC rats treated with 1,4-GL. In vitro, 1,4-GL was observed to reduce lipopolysaccharide-induced ROS levels in NCTC-1469 cells with enhanced mRNA and protein expression of SLC2A9 and decreased mRNA level of XDH. CONCLUSION: The protective effects of 1,4-GL against DEN-induced HCC by reducing uric acid and ROS levels due to down-regulation of uric acid production and up-regulation of SLC2A9 expressions. 1,4-GL may represent a novel treatment that improves recovery from HCC by targeting uric acid-ROS pathway.
Subject(s)
Carcinoma, Hepatocellular , Diethylnitrosamine , Reactive Oxygen Species , Uric Acid , Animals , Diethylnitrosamine/toxicity , Uric Acid/blood , Male , Carcinoma, Hepatocellular/chemically induced , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Rats , Reactive Oxygen Species/metabolism , Liver Neoplasms/chemically induced , Liver Neoplasms/drug therapy , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Rats, Sprague-Dawley , Lactones/pharmacology , Cell Line, Tumor , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/drug therapy , Liver Neoplasms, Experimental/metabolism , Liver Neoplasms, Experimental/pathology , Signal Transduction/drug effects , Drugs, Chinese Herbal/pharmacology , Disaccharides/pharmacologyABSTRACT
Functional connectivity (FC) networks, built from analyses of resting-state magnetic resonance imaging (rs-fMRI), serve as efficacious biomarkers for identifying Autism Spectrum Disorders (ASD) patients. Given the neurobiological heterogeneity across individuals and the unique presentation of ASD symptoms, the fusion of individualized information into diagnosis becomes essential. However, this aspect is overlooked in most methods. Furthermore, the existing methods typically focus on studying direct pairwise connections between brain ROIs, while disregarding interactions between indirectly connected neighbors. To overcome above challenges, we build common FC and individualized FC by tangent pearson embedding (TP) and common orthogonal basis extraction (COBE) respectively, and present a novel multiview brain transformer (MBT) aimed at effectively fusing common and indivinformation of subjects. MBT is mainly constructed by transformer layers with diffusion kernel (DK), fusion quality-inspired weighting module (FQW), similarity loss and orthonormal clustering fusion readout module (OCFRead). DK transformer can incorporate higher-order random walk methods to capture wider interactions among indirectly connected brain regions. FQW promotes adaptive fusion of features between views, and similarity loss and OCFRead are placed on the last layer to accomplish the ultimate integration of information. In our method, TP, DK and FQW modules all help to model wider connectivity in the brain that make up for the shortcomings of traditional methods. We conducted experiments on the public ABIDE dataset based on AAL and CC200 respectively. Our framework has shown promising results, outperforming state-of-the-art methods on both templates. This suggests its potential as a valuable approach for clinical ASD diagnosis.
Subject(s)
Autism Spectrum Disorder , Brain , Magnetic Resonance Imaging , Humans , Autism Spectrum Disorder/diagnostic imaging , Autism Spectrum Disorder/physiopathology , Brain/diagnostic imaging , Magnetic Resonance Imaging/methods , Algorithms , Image Interpretation, Computer-Assisted/methods , Child , MaleABSTRACT
RNA interactomes and their diversified functionalities have recently benefited from critical methodological advances leading to a paradigm shift from a conventional conception on the regulatory roles of RNA in pathogenesis. However, the dynamic RNA interactomes in adenoma-carcinoma sequence of human CRC remain unexplored. The coexistence of adenoma, cancer, and normal tissues in colorectal cancer (CRC) patients provides an appropriate model to address this issue. Here, we adopted an RNA in situ conformation sequencing technology for mapping RNA-RNA interactions in CRC patients. We observed large-scale paired RNA counts and identified some unique RNA complexes including multiple partners RNAs, single partner RNAs, non-overlapping single partner RNAs. We focused on the antisense RNA OIP5-AS1 and found that OIP5-AS1 could sponge different miRNA to regulate the production of metabolites including pyruvate, alanine and lactic acid. Our findings provide novel perspectives in CRC pathogenesis and suggest metabolic reprogramming of pyruvate for the early diagnosis and treatment of CRC.
Subject(s)
Adenoma , Colorectal Neoplasms , MicroRNAs , Pyruvic Acid , RNA, Long Noncoding , Humans , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , Adenoma/genetics , Adenoma/metabolism , Adenoma/pathology , Pyruvic Acid/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Gene Expression Regulation, Neoplastic , Metabolic ReprogrammingABSTRACT
A sensitive and recyclable substrate was fabricated through in situ reduction of silver nanoparticles (NPs) on zinc oxide nanorods (NRs). The prepared silver nanoparticles/zinc oxide nanorods/polyamide mesh (Ag/ZnO/PM) substrate exhibited not only excellent surface-enhanced Raman scattering (SERS) performance to R6G with a limit of detection (LOD) of 10-12 M, mainly attributed to the synergistic effect of the suitable size and the nanoscale gaps of the Ag NPs to produce local surface plasmon resonance (LSPR), but also outstanding self-cleaning property via UV irradiation due to its significant photocatalytic property based on the non-equilibrium carriers generated by ZnO and the presence of Schottky junctions between Ag and ZnO. The substrate showed good recycling stability even after five cycles. Furthermore, the successful recyclable application of Ag/ZnO/PM for tetracycline hydrochloride (TC) detection with high sensitivity further suggested that it is a promising candidate for constructing a portable SERS platform to detect organic pollutants.
ABSTRACT
Aim: Investigation of the pharmacokinetics of sorafenib (SRF) in rats with hepatocellular carcinoma (HCC). Methods: A reproducible ultra-HPLC-MS method for simultaneous determination of serum SRF, N-hydroxymethyl sorafenib and N-demethylation sorafenib. Results: Both the maximum serum concentrations (2.5-times) and the area under the serum concentration-time curve from 0 h to infinity (4.5-times) of SRF were observed to be significantly higher, with a greater than 3.0-fold decrease in the clearance rate in the HCC-bearing rats compared with these values in healthy animals. Further study revealed approximately 3.8- and 3.2-times increases in the apparent Michaelis constant for N-hydroxymethyl sorafenib and N-demethylation sorafenib conversions in the HCC-bearing rats. Conclusion: The low efficiency for the SRF conversions was a key contributor to the increased serum concentrations of SRF.
[Box: see text].
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Niacinamide , Phenylurea Compounds , Sorafenib , Sorafenib/pharmacokinetics , Sorafenib/blood , Sorafenib/therapeutic use , Animals , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/metabolism , Niacinamide/analogs & derivatives , Niacinamide/blood , Niacinamide/pharmacokinetics , Rats , Liver Neoplasms/drug therapy , Liver Neoplasms/metabolism , Male , Phenylurea Compounds/pharmacokinetics , Phenylurea Compounds/blood , Phenylurea Compounds/therapeutic use , Chromatography, High Pressure Liquid/methods , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/blood , Rats, Sprague-Dawley , Mass SpectrometryABSTRACT
Bioactive glasses (BGs) are ideal biomaterials in the field of bio-restoration due to their excellent biocompatibility. Titanium alloys are widely used as a bone graft substitute material because of their excellent corrosion resistance and mechanical properties; however, their biological inertness makes them prone to clinical failure. Surface modification of titanium alloys with bioactive glass can effectively combine the superior mechanical properties of the substrate with the biological properties of the coating material. In this review, the relevant articles published from 2013 to the present were searched in four databases, namely, Web of Science, PubMed, Embase, and Scopus, and after screening, 49 studies were included. We systematically reviewed the basic information and the study types of the included studies, which comprise in vitro experiments, animal tests, and clinical trials. In addition, we summarized the applied coating technologies, which include pulsed laser deposition (PLD), electrophoretic deposition, dip coating, and magnetron sputtering deposition. The superior biocompatibility of the materials in terms of cytotoxicity, cell activity, hemocompatibility, anti-inflammatory properties, bioactivity, and their good bioactivity in terms of osseointegration, osteogenesis, angiogenesis, and soft tissue adhesion are discussed. We also analyzed the advantages of the existing materials and the prospects for further research. Even though the current research status is not extensive enough, it is still believed that BG-coated Ti implants have great clinical application prospects.
ABSTRACT
Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a rare and severe form of end-stage liver disease with high mortality; gut microbes are strongly associated with the development of this severe liver disease but the exact association is unclear. Artificial liver support systems (ALSS) are clinically important in prolonging the waiting time for liver transplantation and in aiding drug therapy to achieve remission. The aim of this study was to investigate the effect of ALSS on the abundance and diversity of microorganisms in the gut of HBV-ACLF patients. In this study, 109 stool samples were collected from patients with hepatitis B virus-associated acute chronic liver failure (HBV-ACLF) for 16S rRNA sequencing. Among them, 44 samples were from patients treated with ALSS therapy as an adjunct to standard medical treatment (SMT) and 65 were from patients receiving SMT only. Analysis of the sequencing results suggested that there were significant differences in the abundance and diversity of gut microbiota between the with-ALSS and without-ALSS groups (p < 0.05). The operational taxonomic units and Shannon indexes indicated that the diversity and abundance of the gut microbiome, while decreasing after the first ALSS treatment, gradually increased after an increase in the number of ALSS therapies. The overall proportion of HBV-ACLF patients with coinfection was 27.59%; the coinfection can reduce the abundance of the Bacteroidetes phylum in the microbiome significantly whereas Proteobacteria were highly enriched. After ALSS therapy, HBV-ACLF patients had a decrease in potentially harmful bacteria, an increase in potentially beneficial bacteria, an increase in the diversity of the intestinal microbiota, and the intestinal microecological disorders were corrected to a certain extent. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TBIL) levels, as well as the international normalized ratio (INR), showed a decreasing trend whereas plasminogen activity (PTA) increased and the condition of patients with HBV-ACLF progressed in a favorable direction. In addition, the abundance of Blautia and Coprococcus was negatively correlated with TBIL and INR, positively correlated with PTA, and positively correlated with disease recovery. Our study shows that ALSS can alter the composition of the gut microbiota and have an ameliorating effect on the gut microecological imbalance in HBV-ACLF patients. It is worth mentioning that Blautia and Coprococcus may have great potential as biomarkers.
ABSTRACT
Objective: The aim of this study was to compare the pharmacokinetics and steady-state serum concentrations of lenvatinib in adult and juvenile rats. Experimental study: An ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) method was developed to quantify lenvatinib in the serum and liver of rats. Six juvenile and six adult rats in each group were orally administered with a single dose of 7.0 mg/kg lenvatinib suspension for pharmacokinetics. Another 12 juvenile and adult rats were subjected to oral gavage with 7.0 mg/kg lenvatinib once daily for 5 days. Biofluild samples were pre-treated by protein precipitation and sorafenib was used as the internal standard for UPLC-MS analysis. The pharmacokinetic parameters were estimated by compartment and statistical model. The mRNA expression of CYP3A2 and SLC22A1 in liver of adult and juvenile rats was measured by real-time fluorescence quantitative PCR (RT-qPCR). Results: The UPLC-MS method met the requirements for quantitative analysis of lenvatinib in serum and liver. The pharmacokinetic results showed that the mean retention time (MRT(0-∞)) was 19.64 ± 7.64 h and 126.38 ± 130.18 h, with AUC(0-∞) values of 3.97 ± 0.73 µgâ§mL-1 h and 5.95 ± 2.27 µg mL-1 h in adult and juvenile rats, respectively. When comparing adult rats (0.35 ± 0.15 µg/mL) to juvenile rats, no significant differences were observed in steady-state serum lenvatinib (0.32 ± 0.11 µg/mL), but a noteworthy decrease to one-third of steady-state liver lenvatinib was observed after multiple oral doses of lenvatinib in juvenile rats. Additional findings revealed that the mRNA expression of CYP3A2 and SLC22A1 was notably increased by 6.86 and 14.67 times, respectively, in juvenile rats compared to adult rats. Conclusion: Juvenile rats exhibit lower levels of lenvatinib in the liver's steady-state, potentially due to the disparity in CYP3A2 mRNA expression. These results imply that the dosage of lenvatinib for pediatric patients may need to be augmented in order to attain the desired clinical outcome.
ABSTRACT
As computer-aided design and computer-aided manufacturing (CAD/CAM) technologies have matured, three-dimensional (3D) printing materials suitable for dentistry have attracted considerable research interest, owing to their high efficiency and low cost for clinical treatment. Three-dimensional printing technology, also known as additive manufacturing, has developed rapidly over the last forty years, with gradual application in various fields from industry to dental sciences. Four-dimensional (4D) printing, defined as the fabrication of complex spontaneous structures that change over time in response to external stimuli in expected ways, includes the increasingly popular bioprinting. Existing 3D printing materials have varied characteristics and scopes of application; therefore, categorization is required. This review aims to classify, summarize, and discuss dental materials for 3D printing and 4D printing from a clinical perspective. Based on these, this review describes four major materials, i.e., polymers, metals, ceramics, and biomaterials. The manufacturing process of 3D printing and 4D printing materials, their characteristics, applicable printing technologies, and clinical application scope are described in detail. Furthermore, the development of composite materials for 3D printing is the main focus of future research, as combining multiple materials can improve the materials' properties. Updates in material sciences play important roles in dentistry; hence, the emergence of newer materials are expected to promote further innovations in dentistry.
ABSTRACT
This study is aimed at performing a systematic review and a network meta-analysis of the effects of several membranes on vertical bone regeneration and clinical complications in guided bone regeneration (GBR) or guided tissue regeneration (GTR). We compared the effects of the following membranes: high-density polytetrafluoroethylene (d-PTFE), expanded polytetrafluoroethylene (e-PTFE), crosslinked collagen membrane (CCM), noncrosslinked collagen membrane (CM), titanium mesh (TM), titanium mesh plus noncrosslinked (TM + CM), titanium mesh plus crosslinked (TM + CCM), titanium-reinforced d-PTFE, titanium-reinforced e-PTFE, polylactic acid (PLA), polyethylene glycol (PEG), and polylactic acid 910 (PLA910). Using the PICOS principles to help determine inclusion criteria, articles are collected using PubMed, Web of Science, and other databases. Assess the risk of deviation and the quality of evidence using the Cochrane Evaluation Manual, and GRADE. 27 articles were finally included. 19 articles were included in a network meta-analysis with vertical bone increment as an outcome measure. The network meta-analysis includes network diagrams, paired-comparison forest diagrams, funnel diagrams, surface under the cumulative ranking curve (SUCRA) diagrams, and sensitivity analysis diagrams. SUCRA indicated that titanium-reinforced d-PTFE exhibited the highest vertical bone increment effect. Meanwhile, we analyzed the complications of 19 studies and found that soft tissue injury and membrane exposure were the most common complications.
Subject(s)
Guided Tissue Regeneration, Periodontal , Titanium , Bone Regeneration , Collagen , Membranes, Artificial , Network Meta-Analysis , PolytetrafluoroethyleneABSTRACT
With the development of ceramic technology, prosthodontic ceramics are becoming a useful option for improving esthetic outcomes in dentistry. In this paper, various ceramic materials were reviewed and evaluated, and their advantages and disadvantages and indications in oral prosthodontics were analyzed objectively. The properties of resin-based ceramics, polycrystalline ceramics, and silicate ceramics were compared and analyzed. Resin-based ceramics may replace other ceramic materials in the CAD/CAM field.
Subject(s)
Ceramics , Computer-Aided Design , Ceramics/chemistry , Ceramics/therapeutic use , Dental Materials/therapeutic use , Dental Porcelain/therapeutic use , Dentistry , Materials Testing , Surface PropertiesABSTRACT
Magnesium alloys have great application prospects as ideal bone implant materials. However, their poor corrosion resistance limits their clinical orthopedic application. Surface modification promotes the corrosion resistance of magnesium. Conversion coatings, such as calcium phosphate (Ca-P) coating, microarc oxidation (MAO) treatment, and fluoride (FLU) treatment, have been extensively investigated in in vivo studies. This systematic review and network meta-analysis compared the influence of different conversion coatings on bone repair, material properties, and systemic host response in orthopedic applications. Using the PICOS model, the inclusion criteria for biodegradable magnesium and its alloys were determined for in vivo studies. Four databases were used. The standard and weight mean differences with 95% confidence intervals were used to analyze new bone formation and degradation rate. Network structure and forest plots were created, and ranking probabilities were estimated. The risk of bias and quality of evidence were assessed using SYRCLE, CERQual, and GRADE tools. In the qualitative analysis, 43 studies were selected, and the evaluation of each outcome indicator was not entirely consistent from article to article. In the quantitative analysis, 21 articles were subjected to network meta-analysis, with 16 articles on implant degradation and 8 articles for new bone formation. Additionally, SUCRA indicated that Ca-P coating exhibited the highest corrosion resistance, followed by FLU treatment. MAO demonstrated the best capability for new bone formation, followed by Ca-P coating. Ca-P coating exhibited the highest overall performance. To conclude, coated Mg can promote better new bone formation than bare Mg and has considerable biocompatibility. Ca-P-coated Mg and MAO-coated Mg have the greatest potential to significantly promote corrosion resistance and bone regeneration, respectively. The findings of this study will provide a theoretical basis for the investigation of composite coatings and guidance for the orthopedic application of Mg bone implants.
ABSTRACT
OBJECTIVE: This review aims to summarize different kinds of applications of minimally invasive surgery in improving facial aging to provide a comprehensive and accurate introduction on the issue of esthetic treatment of facial skin. Overview. In the twentieth century, facial rejuvenation has become a new beauty trend. Facial cosmetology has entered a period of antiaging and rejuvenation therapies and microplastic surgery. The pursuit of beauty has promoted the development of minimally invasive plastic surgery. This review introduces the possible causes of facial aging and its related topics with a focus on facial injectable drugs, such as botulinum toxin, main filler materials (hyaluronic acid, calcium hydroxyapatite, poly L-lactic acid, collagen, autologous fat, and polymethyl methacrylate), and some current antiwrinkle technologies, such as thread lift and radiofrequency rhytidectomy. CONCLUSIONS: Despite the difference in mechanisms of action, each technique can address facial aging involving the loss of collagen, displacement and enlargement of fat, and muscle relaxation. Combinations of these treatments can provide patients with reasonable, comprehensive, and personalized treatment plans.
ABSTRACT
A simple hydrazone probe (1) was designed and synthesized for the successive detection of Al3+ and pyrophosphate (PPi) in almost 100% buffer environment. The probe provided O2N donor set for chelation with Al3+, leading to a distinct fluorescence boost at 510 nm. The in-situ formed 1-Al3+ complex detected PPi with an "on-off" behavior. The detection limits for Al3+ and PPi were 35.7 nM and 76 nM, respectively. Benefiting from the existence of morpholine as lysosome-targeting group, probe 1 was successfully applied to the detection of Al3+ and PPi in lysosomes.
Subject(s)
Fluorescent Dyes , Hydrazones , Lysosomes , Morpholines , Spectrometry, FluorescenceABSTRACT
The spread and application of computer-aided design/computer-aided manufacturing (CAD/CAM) technology have contributed to the rapid development of digitalization in dentistry. The accuracy of scan results is closely related to the devising subsequent treatment plans and outcomes. Professional standards for evaluating scanners are specified in the American National Standard/American Dental Association Standard 132 (ANSI/ADA No. 132). The aims of this study were to use the three samples mentioned in ANSI/ADA No. 132 and evaluate the accuracy and reproducibility of two extraoral scanners and an intraoral scanner based on the inspection standards recommended by ANSI/ADA No. 132. In this study, two trained operators used two extraoral scanners (E4, 3Shape, Denmark & SHINING DS100+, Shining, China) and an intraoral scanner (TRIOS SERIES3, 3Shape, Denmark) to perform 30 scans of each of the three samples at a temperature of 25 ± 2°C and export standard tessellation language files and used reverse engineering software to perform measurements and iterative nearest point matching experiments. The measured values obtained were compared with the reference values measured by a coordinate measuring machine (NC8107, Leader Metrology, USA). We performed a normal distribution test (Shapiro-Wilk test), the nonparametric Kruskal-Wallis test, and an independent-samples t-test to analyze the reproducibility of each scan for different models. The experimental results indicate that the trueness and precision of the two extraoral scanners and the intraoral scanner had a slight mean deviation. The trueness and precision of the three scanners on the curved surface and groove areas are poor. The accuracy and reproducibility of E4 outperformed SHINING and TRIOS. The iterative closest point matching experiment also showed good matching results. The two extraoral scanners and the intraoral scanner in this study can meet the basic clinical requirements in terms of accuracy, and we hope that digital technology will be more widely used in dentistry in the future.
Subject(s)
Computer-Aided Design , Imaging, Three-Dimensional , Digital Technology , Reproducibility of Results , SoftwareABSTRACT
Coating treatment plays an irreplaceable role in propelling the clinical application of magnesium alloys. This experiment was designed in order to observe the anticorrosion behavior of magnesium fluoride coating in rats. The MgF2 layer was prepared on the surface of AZ31 magnesium alloy in saturated NH4HF2 solution by microarc fluorination (MAF) at 190 V. The cross-sectional SEM, EDS, and XRD analysis indicated that the alloy surface was covered with MgF2. Meanwhile, SEM observation was used to compare the magnesium alloy samples before and after treatment, and it was found that the samples after coating were flatter and smoother. Two sets of experiments were carried out with the subjects, 6-week-old male rats. So that the untreated AZ31 samples and the microarc fluorinated AZ31 samples could be buried under the muscle layer individually. The volume changes and surface morphology of the corroded samples were monitored dynamically using micro-CT over a 16-week period in vivo. Comparison of results between the two sets of samples presented that the corrosion of the microarc fluoridated samples was much slower than that of the untreated ones. The MAF coating was shown to be effective in controlling the corrosion rate and progression of the magnesium alloy.
Subject(s)
Halogenation , Magnesium , Alloys , Animals , Coated Materials, Biocompatible , Corrosion , Cross-Sectional Studies , Male , RatsABSTRACT
In the ongoing research on the application of biodegradable materials, surface treatment of is considered to be a relatively effective solution to the excessive degradation rates of Mg alloys. In this study, to further optimize the proven effective surface coatings of fluoride, a low-voltage preparation fluorination method was used to achieve coating effectiveness under safer conditions. Optical observation, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and potential dynamic polarization (PDP) experiments were used for the analysis and evaluation. The coating characteristics of the MgF2 coatings treated in the 10-90 V voltage range, including the structure, chemical conformation, and electrochemical corrosion assessment, were fully defined. The anodic fluoridation results showed that a pore structure of 1-14 µm thickness was formed on the Mg alloy substrate, and the coating was composed of Mg fluoride. The results of immersion corrosion and electrochemical corrosion experiments showed that compared with pure Mg, anodic fluorinated samples below 40 V exhibited better corrosion resistance, the prepared MgF2 coating was more uniform, and the surface mostly exhibited point corrosion. When the voltage reached or exceeded 60 V, the prepared coating exhibited poor corrosion resistance, fracture, and protrusions. After corrosion, it mostly exhibited surface corrosion. The results indicate that idealized coatings can be obtained at relatively low and safe voltage ranges. This finding may enable more economical, environmentally friendly, and safe preparation of coatings.
ABSTRACT
The aim of this study was to evaluate the potential of tooth biomaterials as bone graft biomaterials for bone healing in rabbits. We prepared tooth biomaterial and platelet-rich fibrin (PRF) to fill the round-shaped defect in the skull of New Zealand white rabbits. These cranial defects were treated with different conditions as follows: group 1, a mixture of tooth biomaterials and platelet-rich fibrin (PRF); group 2, only tooth biomaterials; group 3, only PRF; and group 4, the unfilled control group. Specimens of the filled sites were harvested for analysis with microscopic computerized tomography (micro-CT) and histomorphology at 4 and 8 weeks. As a result of micro-CT, at 4 weeks, the bone volume percentages in groups 1 and 2 were 50.33 ± 6.35 and 57.74 ± 3.13, respectively, and that in the unfilled control group was 42.20 ± 10.53 (p = 0.001). At 8 weeks, the bone volume percentages in groups 1 and 2 were 53.73 ± 9.60 and 54.56 ± 8.44, respectively, and that in the unfilled control group was 37.86 ± 7.66 (p = 0.002). The difference between the experimental group 3 and the unfilled control group was not statistically significant. Histomorphologically, the total new bone was statistically different.
Subject(s)
Platelet-Rich Fibrin , Animals , Biocompatible Materials , Bone Regeneration , Fibrin , Models, Animal , Rabbits , X-Ray MicrotomographyABSTRACT
Our study was aimed to analyze the osteoinductive effect of powdered and block type autogenous bone graft along with bone morphogenetic protein (BMP-2) as compared to synthetic bone graft. Three circular bicortical defects were made in the calvaria of each rabbit and randomly divided into three groups as follows: powdered tooth biomaterial+BMP-2, block tooth biomaterial+BMP-2, and control group: synthetic bone+BMP-2. The samples taken from these defects after 4 and 8 weeks were analyzed histologically along with micro CT analysis. In our study, both powered and block type tooth autogenous bone graft successfully stimulated mesenchymal cells leading to endochondral ossification and bone regeneration. We observed that the powered bone graft material which is acid insoluble especially is preferable as a carrier for BMP-2.
Subject(s)
Biocompatible Materials , Bone Morphogenetic Protein 2 , Animals , Bone Morphogenetic Proteins , Bone Regeneration , Rabbits , X-Ray MicrotomographyABSTRACT
This study is aimed at assessing the dimensional alterations occurring in the alveolar bone after premolar extraction in dogs with histomorphometric and histological analysis. After atraumatic premolar extraction, tooth-derived bone graft material was grafted in the extraction socket of the premolar region in the lower jaws of six dogs in two experimental groups. In the second experimental group, BM-MSCs were added together with the graft. The control was left untreated on the opposite side. After twelve weeks, all six animals were sacrificed. Differences in alveolar bone height crests lingually and buccally, and alveolar bone width at 1, 3, and 5 mm infracrestally, were examined. Histologic study revealed osteoconductive properties of tooth biomaterial. A statistically significant difference was detected between the test and control groups. In the test groups, a reduced loss of vertical and horizontal alveolar bone dimensions compared with the control group was observed. Tooth bone graft material may be considered useful for alveolar ridge preservation after tooth extraction, as it could limit the natural bone resorption process.