The genomes of seven economic Caesalpinioideae trees provide insights into polyploidization history and secondary metabolite biosynthesis.

The Caesalpinioideae subfamily contains many well-known trees that are important for the sustainability of the economy and human health, but the lack of genomic resources hindered the breeding and utilization of these plants. Here, we present chromosome-level reference genomes for two food and industrial trees Gleditsia sinensis (921 Mb) and Biancaea sappan (872 Mb), three shade and ornamental trees Albizia julibrissin (705 Mb), Delonix regia (580 Mb) and Acacia confusa (566 Mb), as well as two pioneer and hedgerow trees Leucaena leucocephala (1,338 Mb) and Mimosa bimucronata (641 Mb). Phylogeny inference showed that the mimosoid clade has a much higher evolution rate than the other clades of Caesalpinioideae. Macrosynteny comparison showed that the fusion and broken of an unstable chromosome was responsible for the difference in the basic chromosome number 13 and 14 for Caesalpinioideae. After the ancient whole genome duplication shared by all Caesalpinioideae species (CWGD, ∼72.0 MYA), we found two recent successive WGD events LWGD-1 (16.2-19.5 MYA) and LWGD-2 (7.1-9.5 MYA) in L. leucocephala. Then, ∼40% gene loss and genome size contraction occurred during the diploidization process in L. leucocephala. For the secondary metabolites, we identified all the gene copies involved in mimosine metabolism for these species and revealed that the abundance of mimosine biosynthesis genes in L. leucocephala largely explains its high mimosine production. Moreover, we identified all the potential genes involved in triterpenoid saponin biosynthesis in G. sinensis, which is more complete than the previous transcriptome-derived unigenes. Our analyzing results and the genomic resources will facilitate the biological studies of Caesalpinioideae and promote the utilization of valuable secondary metabolites.

Appreciable biosafety, biocompatibility and osteogenic capability of 3D printed nonstoichiometric wollastonite scaffolds favorable for clinical translation.

Background: Alveolar bone destruction due to periodontal disease often requires a bone graft substitute to reconstruct the anatomical structures and biological functions of the bone tissue. Despite significant advances in the development of foreign ion-doped nonstoichiometric wollastonite bioceramics (CaSiO3, nCSi) for alveolar bone regeneration over the past decade, the in vivo biosafety and osteogenesis of nCSi scaffolds remain uncertain. In this study, we developed a customized porous nCSi scaffold to investigate the in vivo biocompatibility and osteogenic properties of nCSi bioceramics. Methods: Six percent Mg-doped nCSi bioceramic scaffolds were fabricated by digital light processing (DLP), and the scaffold morphology, pore architecture, compressive strength, in vitro biodegradation, and apatite-forming ability of the bioceramic scaffolds were investigated systematically. Subsequently, an alveolar bone defect rabbit model was used to evaluate the biocompatibility and osteogenic efficacy of the nCSi bioceramics. Animal weight, hematological test, blood biochemical test, wet weight of the main organs, and pathological examination of the main organs were conducted. Micro-CT and histological staining were performed to analyze the osteogenic potential of the personalized bioceramic scaffolds. Results: The nCSi scaffolds exhibited appreciable initial compressive strength (>30 MPa) and mild mechanical decay over time during in vitro biodissolution. In addition, the scaffolds induced apatite remineralization in SBF. Bioceramic scaffolds have been proven to have good biocompatibility in vivo after implantation into the alveolar bone defect of rabbits. No significant effects on the hematological indices, blood biochemical parameters, organ wet weight, or organ histopathology were detected from 3 to 180 days postoperatively. The porous scaffolds exhibited strong bone regeneration capability in the alveolar bone defect model of rabbits. Micro-CT and histological examination showed effective maintenance of bone morphology in the bioceramic scaffold group; however, depressed bone tissue was observed in the control group. Conclusions: Our results suggest that personalized nCSi bioceramic scaffolds can be fabricated using the DLP technique. These newly developed strong bioceramic scaffolds exhibit good biocompatibility and osteogenic capability in vivo and have excellent potential as next-generation oral implants. The translational potential of this article: Tissue-engineered strategies for alveolar bone repair require a bone graft substitute with appreciable biocompatibility and osteogenic capability. This article provides a systematic investigation of the in vivo biosafety and osteogenic property of nCSi to further development of a silicate-based bioceramics materials for clinical applications.

Bioceramic scaffolds with two-step internal/external modification of copper-containing polydopamine enhance antibacterial and alveolar bone regeneration capability. / å«é“œèšå¤šå·´èƒºå† å¤–åŒä¿®é¥°æ³•æž„å»ºæŠ—èŒä¿ƒéª¨å†ç”Ÿç”Ÿç‰©é™¶ç“·æ”¯æž¶.

Magnesium-doped calcium silicate (CS) bioceramic scaffolds have unique advantages in mandibular defect repair; however, they lack antibacterial properties to cope with the complex oral microbiome. Herein, for the first time, the CS scaffold was functionally modified with a novel copper-containing polydopamine (PDA(Cu2+|)) rapid deposition method, to construct internally modified (*P), externally modified (@PDA), and dually modified (*P@PDA) scaffolds. The morphology, degradation behavior, and mechanical properties of the obtained scaffolds were evaluated in vitro. The results showed that the CS*P@PDA had a unique micro-/nano-structural surface and appreciable mechanical resistance. During the prolonged immersion stage, the release of copper ions from the CS*P@PDA scaffolds was rapid in the early stage and exhibited long-term sustained release. The in vitro evaluation revealed that the release behavior of copper ions ascribed an excellent antibacterial effect to the CS*P@PDA, while the scaffolds retained good cytocompatibility with improved osteogenesis and angiogenesis effects. Finally, the PDA(Cu2+)-modified scaffolds showed effective early bone regeneration in a critical-size rabbit mandibular defect model. Overall, it was indicated that considerable antibacterial property along with the enhancement of alveolar bone regeneration can be imparted to the scaffold by the two-step PDA(Cu2+) modification, and the convenience and wide applicability of this technique make it a promising strategy to avoid bacterial infections on implants.

Application of digital technology and platelet-rich fibrin technology in a novel regenerative treatment for posterior lingual furcation defect: a 6-year follow-up case report.

Conventional periodontal regenerative surgery has limited effect on tooth with severe periodontitis-related alveolar bone defects. This article reported a case of regenerative treatment in severe distal-bone defect of mandibular first molar. The treatment involved applying 3D printing, advanced/injectable platelet-rich fibrin, and guided tissue-regeneration technology. After the operation, the periodontal clinical index significantly improved and the alveolar bone was well reconstructed.

Causal relationship between circulating lipid traits and periodontitis: univariable and multivariable Mendelian randomization.

Introduction: The correlation between dyslipidemia and periodontitis is revealed through epidemiological studies. However, the results are affected by several confounding factors. This study aims to elucidate the genetic causal association between circulating lipid traits and periodontitis by two-sample Mendelian randomization (MR) analysis. Methods: After the different screening processes, two cohorts of circulating lipid traits from the UK Biobank were used as exposure data, including five circulating lipid traits. The Periodontitis cohort was selected from the GeneLifestyle Interactions in Dental Endpoints (GLIDE) consortium as outcome data. In univariable MR, the inverse variance weighted (IVW) was used in conjunction with six additional analytical methods to assess causality. The Cochran Q test, IGX 2 statistic, MR-PRESSO, and MR-Egger intercept were used to quantify heterogeneity and pleiotropy. The multivariable MR-IVW (MVMR-IVW) and MVMR-robust were mainly used as analytical methods in the multiple MR analyses. Results: The IVW estimates showed that genetically predicted Apolipoprotein A1 (apo A1) [odds ratio (OR)=1.158, 95% confidence interval (CI)=1.007-1.331, P-value=0.040] was potentially associated with the risk of periodontitis, but the statistical power of the results was low. Multivariable MR analysis did not reveal any significant causal relationship between apo A1 and periodontitis (OR=0.72, 95% CI=0.36-1.41, P-value=0.34). In the validation cohort, there was also no significant causal relationship between apo A1 and periodontitis (OR=1.079, 95% CI=0.903-1.290, P-value=0.401). Meanwhile, genetically predicted Apolipoprotein B (apo B), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) (all P-values>0.05) were not significantly associated with the risk of periodontitis causal inference. Conclusion: This MR analysis was unable to provide genetic evidence for the influence of these five circulating lipid traits on periodontitis. However, a more extensive study with a more comprehensive circulating lipid profile and periodontitis data is needed due to study limitations.

Chromosome-scale Amaranthus tricolor genome provides insights into the evolution of the genus Amaranthus and the mechanism of betalain biosynthesis.

Amaranthus tricolor is a vegetable and ornamental amaranth, with high lysine, dietary fibre and squalene content. The red cultivar of A. tricolor possesses a high concentration of betalains, which has been used as natural food colorants. Here, we constructed the genome of A. tricolor, the first reference genome for the subgenus Albersia, combining PacBio HiFi, Nanopore ultra-long and Hi-C data. The contig N50 size was 906 kb, and 99.58% of contig sequence was anchored to the 17 chromosomes, totalling 520 Mb. We annotated 27,813 protein-coding genes with an average 1.3 kb coding sequence and 5.3 exons. We inferred that A. tricolor underwent a whole-genome duplication (WGD) and that the WGD shared by amaranths occurred in the last common ancestor of subfamily Amaranthoideae. Moreover, we comprehensively identified candidate genes in betalain biosynthesis pathway. Among them, DODAα1 and CYP76ADα1, located in one topologically associated domain (TAD) of an active (A) compartment on chromosome 16, were more highly expressed in red leaves than in green leaves, and DODAα1 might be the rate-limiting enzyme gene in betalains biosynthesis. This study presents new genome resources and enriches our understanding of amaranth evolution, betalains production, facilitating molecular breeding improvements and the understanding of C4 plants evolution.

Modularized bioceramic scaffold/hydrogel membrane hierarchical architecture beneficial for periodontal tissue regeneration in dogs.

BACKGROUND: Destruction of alveolar bone and periodontal ligament due to periodontal disease often requires surgical treatment to reconstruct the biological construction and functions of periodontium. Despite significant advances in dental implants in the past two decades, it remains a major challenge to adapt bone grafts and barrier membrane in surgery due to the complicated anatomy of tooth and defect contours. Herein, we developed a novel biphasic hierarchical architecture with modularized functions and shape based on alveolar bone anatomy to achieve the ideal outcomes. METHODS: The integrated hierarchical architecture comprising of nonstoichiometric wollastonite (nCSi) scaffolds and gelatin methacrylate/silanized hydroxypropyl methylcellulose (GelMA/Si-HPMC) hydrogel membrane was fabricated by digital light processing (DLP) and photo-crosslinked hydrogel injection technique respectively. The rheological parameters, mechanical properties and degradation rates of composite hydrogels were investigated. L-929 cells were cultured on the hydrogel samples to evaluate biocompatibility and cell barrier effect. Cell scratch assay, alkaline phosphatase (ALP) staining, and alizarin red (AR) staining were used to reveal the migration and osteogenic ability of hydrogel membrane based on mouse mandible-derived osteoblasts (MOBs). Subsequently, a critical-size one-wall periodontal defect model in dogs was prepared to evaluate the periodontal tissue reconstruction potential of the biphasic hierarchical architecture. RESULTS: The personalized hydrogel membrane integrating tightly with the nCSi scaffolds exhibited favorable cell viability and osteogenic ability in vitro, while the scratch assay showed that osteoblast migration was drastically correlated with Si-HPMC content in the composite hydrogel. The equivalent composite hydrogel has proven good physiochemical properties, and its membrane exhibited potent occlusive effect in vivo; meanwhile, the hierarchical architectures exerted a strong periodontal regeneration capability in the periodontal intrabony defect models of dogs. Histological examination showed effective bone and periodontal ligament regeneration in the biomimetic architecture system; however, soft tissue invasion was observed in the control group. CONCLUSIONS: Our results suggested that such modularized hierarchical architectures have excellent potential as a next-generation oral implants, and this precisely tuned guided tissue regeneration route offer an opportunity for improving periodontal damage reconstruction and reducing operation sensitivity.

A chromosome-level reference genome of a Convolvulaceae species Ipomoea cairica.

Ipomoea cairica is a perennial creeper that has been widely introduced as a garden ornamental across tropical, subtropical, and temperate regions. Because it grows extremely fast and spreads easily, it has been listed as an invasive species in many countries. Here, we constructed the chromosome-level reference genome of Ipomoea cairica by Pacific Biosciences HiFi and Hi-C sequencing, with the assembly size of 733.0 Mb, the contig N50 of 43.8 Mb, the scaffold N50 of 45.7 Mb, and the Benchmarking Universal Single-Copy Orthologs complete rate of 98.0%. Hi-C scaffolding assigned 97.9% of the contigs to 15 pseudo-chromosomes. Telomeric repeat analysis reveals that 7 of the 15 pseudo-chromosomes are gapless and telomere to telomere. The transposable element content of Ipomoea cairica is 73.4%, obviously higher than that of other Ipomoea species. A total of 38,115 protein-coding genes were predicted, with the Benchmarking Universal Single-Copy Orthologs complete rate of 98.5%, comparable to that of the genome assembly, and 92.6% of genes were functional annotated. In addition, we identified 3,039 tRNA genes and 2,403 rRNA genes in the assembled genome. Phylogenetic analysis showed that Ipomoea cairica formed a clade with Ipomoea aquatica, and they diverged from each other 8.1 million years ago. Through comparative genome analysis, we reconfirmed that a whole genome triplication event occurred specific to Convolvulaceae family and in the ancestor of the genus Ipomoea and Cuscuta. This high-quality reference genome of Ipomoea cairica will greatly facilitate the studies on the molecular mechanisms of its rapid growth and invasiveness.

Research progress on the relationship between chronic periodontitis and Parkinson's disease.

Chronic periodontitis is an infectious disease, which has a reciprocal relationship with a variety of systemic disorders. Parkinson's disease is a prevalent neurodegenerative disease in which inflammation plays an important role for its progression. A vast number of studies suggest that there is a potential connection between chronic periodontitis and neurodegenerative diseases such as Parkinson's disease. Individuals with Parkinson's disease usually have poor periodontal health, and their oral flora composition differs from that of healthy people; at the same time, patients with chronic periodontitis have a higher risk of Parkinson's disease, which can be reduced with regular periodontal treatment. In fact, the mechanism of interaction between chronic periodontitis and Parkinson's disease is not clear. According to several studies, the clinical symptoms of Parkinson's disease prevent patients to maintain oral hygiene effectively, increasing the risk of periodontitis. Neuroinflammation mediated by microglia may be the key to the influence of chronic periodontitis on Parkinson's disease. Periodontal pathogens and inflammatory mediators may enter the brain and activate microglia in various ways, and ultimately leading to occurrence and development of Parkinson's disease. This article reviews the recent research progress on the association between chronic periodontitis and Parkinson's disease, and its potential mechanism to provide information for further research.

Recovery of metagenome-assembled microbial genomes from a full-scale biogas plant of food waste by pacific biosciences high-fidelity sequencing.

Background: Anaerobic digestion (AD) is important in treating of food waste, and thousands of metagenome-assembled genomes (MAGs) have been constructed for the microbiome in AD. However, due to the limitations of the short-read sequencing and assembly technologies, most of these MAGs are grouped from hundreds of short contigs by binning algorithms, and the errors are easily introduced. Results: In this study, we constructed a total of 60 non-redundant microbial genomes from 64.5 Gb of PacBio high-fidelity (HiFi) long reads, generated from the digestate samples of a full-scale biogas plant fed with food waste. Of the 60 microbial genomes, all genomes have at least one copy of rRNA operons (16S, 23S, and 5S rRNA), 54 have ≥18 types of standard tRNA genes, and 39 are circular complete genomes. In comparison with the published short-read derived MAGs for AD, we found 23 genomes with average nucleotide identity less than 95% to any known MAGs. Besides, our HiFi-derived genomes have much higher average contig N50 size, slightly higher average genome size and lower contamination. GTDB-Tk classification of these genomes revealed two genomes belonging to novel genus and four genomes belonging to novel species, since their 16S rRNA genes have identities lower than 95 and 97% to any known 16S rRNA genes, respectively. Microbial community analysis based on the these assembled genomes reveals the most predominant phylum was Thermotogae (70.5%), followed by Euryarchaeota (6.1%), and Bacteroidetes (4.7%), and the most predominant bacterial and archaeal genera were Defluviitoga (69.1%) and Methanothrix (5.4%), respectively. Analysis of the full-length 16S rRNA genes identified from the HiFi reads gave similar microbial compositions to that derived from the 60 assembled genomes. Conclusion: High-fidelity sequencing not only generated microbial genomes with obviously improved quality but also recovered a substantial portion of novel genomes missed in previous short-read based studies, and the novel genomes will deepen our understanding of the microbial composition in AD of food waste.

Interleukin-17 induces pyroptosis in osteoblasts through the NLRP3 inflammasome pathway in vitro.

OBJECTIVE: Interleukin-17 (lL-17), a pro-inflammatory cytokine produced by Th17 cells, is also considered to play an important role in bone metabolism, but the exact mechanism of bone destruction remains unclear. In this study, we explored whether IL-17 could induce osteoblasts pyroptosis in vitro. METHODS: The murine primary osteoblasts were isolated from the calvarial bones of mice. The proliferation of osteoblasts was evaluated by cell counting kit-8 (CCK-8) assay. The mRNA levels of NOD-like receptor family pyrin domain containing 3 (NLRP3), apoptosis associated speck like protein containing a card (ASC), caspase-1, gasdermin-D (GSDMD), IL-1ß and receptor activator of nuclear factor-kappa B ligand (RANKL) were measured by real-time quantitative PCR. Pyroptosis after IL-17 treatment was evaluated by lactate dehydrogenase (LDH) Release Assay Kit and the morphological characteristics of osteoblasts were observed via Scanning Electron Microscopy (SEM). Pyroptosis associated proteins, cleaved IL-1ß and RANKL were evaluated through western blot. The release of IL-1ß and RANKL was measured by ELISA. In addition, calcium nodule was tested by alizarin red staining. RESULTS: High concentration IL-17 (100 ng/mL) could affect the proliferation of osteoblasts, promote the gene expression of NLRP3, caspase-1, GSDMD, IL-1ß and RANKL. In contrast to control group, osteoblasts treated with IL-17 had the appearance of numerous pores, swelling and rupture. Also, the release of LDH, IL-1ß and RANKL increased in the presence of IL-17. However, inhibition of NLRP3 prevented activation of the NLRP3 inflammasome, thereby restoring osteoblasts morphology and function. CONCLUSION: IL-17 induced osteoblasts pyroptosis, and the pyroptosis of osteoblasts may prompt the release of IL-1ß and RANKL,which may further contribute to disruption of bone metabolism. Besides, the NLRP3 inflammasome pathway was involved in the pyroptosis of osteoblasts.

Tuning filament composition and microstructure of 3D-printed bioceramic scaffolds facilitate bone defect regeneration and repair.

It is still a challenge to optimize the component distribution and microporous structures in scaffolds for tailoring biodegradation (ion releasing) and enhancing bone defect repair within an expected time stage. Herein, the core-shell-typed nonstoichiometric wollastonite (4% and 10% Mg-doping calcium silicate; CSiMg4, CSiMg10) macroporous scaffolds with microporous shells (adding ∼10 µm PS microspheres into shell-layer slurry) were fabricated via 3D printing. The initial mechanical properties and bio-dissolution (ion releasing) in vitro, and osteogenic capacity in vivo of the bioceramic scaffolds were evaluated systematically. It was shown that endowing high-density micropores in the sparingly dissolvable CSiMg10 or dissolvable CSiMg4 shell layer inevitably led to nearly 30% reduction of compressive strength, but such micropores could readily tune the ion release behaviour of the scaffolds (CSiMg4@CSiMg10 vs. CSiMg4@CSiMg10-p; CSiMg10@CSiMg4 vs. CSiMg10@CSiMg4-p). Based on the in rabbit femoral bone defect repair model, the 3D µCT reconstruction and histological observation demonstrated that the CSiMg4@CSiMg10-p scaffolds displayed markedly higher osteogenic capability than the other scaffolds after 12 weeks of implantation. It demonstrated that core-shell bioceramic 3D printing technique can be developed to fabricate single-phase or biphasic bioactive ceramic scaffolds with accurately tailored filament biodegradation for promoting bone defect regeneration and repair in some specific pathological conditions.

Global burden of periodontal disease and its relation with socioeconomic development during 1990-2019.

To analyze the global burden of periodontal disease and its relation with socioeconomic development. Data of global disability-adjusted life year (DALY) due to periodontal disease and human development index (HDI) from 1990 to 2019 were obtained from Global Health Data Exchange (GHDx) and human development reports. The trend of the global burden of periodontal disease from 1990 to 2019 was described. The correlation between age-standardized DALY rates and HDI were examined in 2019, and between-country periodontal disease burden inequality from 1990 to 2019 was measured using health-related Gini coefficients and concentration indexes. From 1990 to 2019, the global DALY rate due to periodontal disease increased from 78.63 to 85.48, and the epidemiological burden did not increase significantly. Statistical differences were found across different HDI categories for age-standardized DALY rates of periodontal disease ( 44.315, <0.01) in 2019. Linear regression analysis also revealed a negative correlation between age-standardized DALY rate of periodontal disease and HDI ( = -0.417, <0.01) . Gini coefficients decreased from 0.361 to 0.281 and concentration indexes fell from 0.0339 to -0.0538 between 1990 and 2019. The global burden of periodontal disease did not increase between 1990 and 2019, though the socioeconomic-associated inequality still existed. The burden of periodontal disease was more concentrated in less developed countries, and the socioeconomic-associated inequality has increased since 2000.

RANKL expression of primary osteoblasts is enhanced by an IL-17-mediated JAK2/STAT3 pathway through autophagy suppression.

Objective: Interleukin-17 (IL-17), produced by T helper (Th)-17 cells, is a potent regulator of bone homeostasis. Osteoblasts are key cells that orchestrate inflammatory bone destruction and bone remodeling. This study examines the effect of different concentrations of IL-17 on osteogenesis and receptor activator of nuclear factor-kappa B ligand (RANKL) expression of primary osteoblasts.Methods: First, the growth of primary osteoblasts was evaluated. Second, we assessed the effects of IL-17 on the level of autophagy and the related Janus activated kinase 2 (JAK2) and downstream signal transducer and activator of transcription 3 (STAT3) signaling pathway. Next, osteogenic activity in different concentrations of IL-17 was tested. Finally, the specific JAK2/STAT3 signaling pathway inhibitor AG490 and autophagy inhibitor 3-MA were used to investigate the involvement of this pathway and autophagy in IL-17-induced regulation of RANKL expression.Results: Initially, we found that IL-17 treatment promoted growth of osteoblasts in a time- and dose-dependent manner. Next, we showed that low levels of IL-17 promoted autophagy activity, whereas the opposite was observed at high levels of IL-17. Moreover, high levels of IL-17 activated the JAK2/STAT3 signaling pathway, although this effect was reversed by upregulation of autophagy. Furthermore, our findings indicated that high concentrations of IL-17 promoted the differentiation, calcification, and RANKL expression of murine osteoblasts via activation of the JAK2/STAT3 pathway. Importantly, downregulation of autophagy at high IL-17 concentrations further enhanced RANKL expression via suppressing the JAK2/STAT3 cascade.Conclusion: Overall, our findings demonstrate, for the first time, that IL-17 modulates RANKL expression of osteoblasts through an autophagy-JAK2-STAT3 signaling pathway, thus affecting bone metabolism.

Biphasic ceramic biomaterials with tunable spatiotemporal evolution for highly efficient alveolar bone repair.

Alveolar bone defects, which are characterized by a relatively narrow space and location adjacent to the cementum, require promising substitute biomaterials for their regeneration. In this study, we introduced novel yolk-shell biphasic bio-ceramic granules with/without a customized porous shell and evaluated their biological effect together with structural transformation. Firstly, a self-made coaxial bilayer capillary system was applied for the fabrication of granules. Secondly, thorough morphological and physicochemical characterizations were performed in vitro. Subsequently, the granules were implanted into critical-size alveolar bone defects (10 × 4 × 3 mm) in New Zealand white rabbits, with Bio-Oss® as the positive control. Finally, at 2, 4, 8, and 16 weeks postoperatively, the alveolar bone specimens were harvested and assessed via radiological and histological examination. Our results showed that the yolk-shell biphasic bio-ceramic granules, especially those with porous shells, exhibited a tunable ion release performance, improved biodegradation behavior and satisfactory osteogenesis compared with the homogeneously hybrid and Bio-Oss® granules both in vitro and in vivo. This study provides the first evidence that novel yolk-shell bio-ceramic granules, on account of their adjustable porous microstructure, have great potential in alveolar bone repair.

Core-Shell Bioactive Ceramic Robocasting: Tuning Component Distribution Beneficial for Highly Efficient Alveolar Bone Regeneration and Repair.

Biodegradable ceramic (composite) scaffolds have inspired worldwide efforts in bone regenerative medicine. However, balancing the biodegradation with the bone's natural healing time scale remains difficult; in particularl, there is a lack of strategy to control component distribution and bioactive ion release favorable for stimulating alveolar bone tissue ingrowth in situ within an expected time window. Here we aimed to develop the robocasting core-shell bioceramic scaffolds and investigate their physicochemical properties and osteostimulative capability in beagle alveolar bone defect model. The ß-tircalcium phosphate (TCP) and 5% Mg-doped calcium silicate (CSi-Mg5) were used to fabricate the core-shell-typed TCP@TCP, CSi-Mg5@CSi-Mg5 and TCP@CSi-Mg5 porous scaffolds. Both in vitro and in vivo studies show that the CSi-Mg5 shell readily contributed to the initial mechanical strength and early-stage osteogenic activity of the TCP@CSi-Mg5 scaffolds, including tunable ion release, enhanced biodegradation, and outstanding osteogenesis capacity in comparison with the CSi-Mg5@CSi-Mg5 scaffolds and clinically available Bio-Oss granules in alveolar bone defects. Therefore, the presented core-shell robocasting of bioceramic technology and porous scaffold biomaterials enables an accurate preparation of highly bioactive and biodegradable scaffolds with a large freedom of design, and thereby may be beneficial for fabricating osteostimulation-tuned porous scaffolds for the challengeable alveolar bone defect reconstruction medicine.

Effect of Foreign Ion Substitution and Micropore Tuning in Robocasting Single-Phase Bioceramic Scaffolds on the Physicochemical Property and Vascularization.

The inorganic powder slurry extrusion printing technique known as robocasting is an interesting method to fabricate complex porous architectures whereby feedstocks containing organic binders and powders are printed and the resulting scaffolds are subjected to sintering. A major limiting factor of this technique is the simultaneous tailoring of vascularization efficacy and osteogenic activity, usually done by adding the secondary phase in the organic slurry before the writing step. Mechanical mixing of biphasic powders is required to avoid compromising the biological performance and physical defects caused by significantly different physicochemical properties. This study addresses this issue by developing a selective ion doping and microstructure tuning for the production of bioceramic scaffolds with a binozzle robocasting process. Different metal ions (Sr2+, Mg2+) were doped into wollastonite (CaSiO3; CSi) powders considering the mechanical stability and bioactive enhancement of the bioceramic scaffolds. Subsequently, the Mg-doped CSi slurries were used as shell-nozzle feedstocks added with 5, 10, and 15 µm diameter polystyrene microbeads that allowed shell-layer micropore production in pore struts during sintering. Finally, the most promising pore-strut microstructures and mechanical evolution of scaffolds were evaluated, and especially the enhanced fibrovascularization potential was confirmed in dorsal muscle embedding model in rabbits. This study may open an avenue to designing multiproperty-tuned macro- and microporous bioceramics for bone regenerative medicine, especially in challenging bone defect conditions.

Quantification of growth factors in advanced platelet-rich fibrin and concentrated growth factors and their clinical efficacy as adjunctive to the GTR procedure in periodontal intrabony defects.

BACKGROUND: The development of platelet concentrated biomaterials has gained increasing awareness for regenerative medicine. With different protocol, derivatives such as advanced platelet-rich fibrin (A-PRF), injected platelet-rich fibrin, and concentrated growth factor (CGF) have been demonstrated effectively in preclinical and clinical studies. The aim of this study was to compare the level of growth factors releasing from A-PRF and CGF, and their clinical efficacy in the regenerative management of intrabony defects (IBDs). METHODS: Thirty-two blood samples were collected from eight healthy donors and assessed for platelet-derived growth factor-αß, vascular endothelial growth factor, bone morphogenetic protein-2, and transforming growth factor-ß1 release at indicated times. In addition, the clinical records of 45 patients (15 per group) who had undergone guided tissue regeneration (GTR) with or without A-PRF/CGF were retrieved. The probing depth (PD) and clinical attachment level (CAL) were recorded preoperatively and 6 months postoperatively. Intrabony component (IC) depth, radiographic bone level (RBL), and bone defect filling were assessed radiographically. RESULTS: A-PRF had a looser fibrin network than the CGF but presented larger amounts of growth factors with a more sustained release period. Although there was no difference in PD reduction, CAL gain, RBL height change and defect filling (%) between A-PRF and CGF group, both achieved a more favorable clinical result in IC height reduction and defect filling (%) than the control. CONCLUSIONS: A-PRF and CGF have the ability to stimulate a continual and steady release of total growth factors over a 14-day period. A-PRF and CGF show a similar effectiveness in periodontal bone regeneration with a potential benefit of improving GTR outcomes in IBD treatment.

The Application of Three-Dimensional Printing Model and Platelet-Rich Fibrin Technology in Guided Tissue Regeneration Surgery for Severe Bone Defects.

A 36-year-old male patient diagnosed with severe chronic periodontitis was treated with novel surgery for his maxillary right lateral incisor. Preoperatively, a 3D printer was used, based on CBCT datasets, to produce a photosensitive resin bony anatomy replica. The patient's blood was centrifuged to obtain advanced platelet-rich fibrin (A-PRF) and injected platelet-rich fibrin (I-PRF), then mixed with Bio-Oss and packed onto the 3D replica to form the ideal shape. The replica was positioned at the planned sites without changes. The A-PRF membrane was applied over the replica as well as a Bio-Gide collagen membrane. Fifteen months after the surgery, clinical and radiographic followup revealed greatly reduced pocket depths and significant 3D alveolar bone fill at the treatment site. Based on these short-term results, the initial 3D printing surgical temple assisted guided tissue regeneration method resulted in significant clinical and radiographic improvements; A-PRF/I-PRF should be considered an ideal biomaterial for regenerative periodontal therapy.

The positive effects of secreting cytokines IL-17 and IFN-γ on the early-stage differentiation and negative effects on the calcification of primary osteoblasts in vitro.

OBJECTIVE: Interleukin-17 (IL-17) and interferon-gamma (IFN-γ) are all pro-inflammatory cytokines produced by specific subsets of T-cells and are also considered crucial regulators in bone remodeling, but their effects on osteogenesis have not been carefully studied. So, this study aimed to investigate the effects of secreting cytokines IL-17 and IFN-γ on the osteogenesis of primary osteoblasts and to clarify the potential roles of the related Janus activated kinase 2 (JAK2) and downstream signal transducer and activator of transcription 3 (STAT3) signaling pathway in bone remodeling. METHODS: The proliferation of osteoblasts was evaluated by MTT assay. Osteogenic activity was tested by alkaline phosphatase (ALP) activity assay and alizarin red staining. The mRNA levels of ALP, osteocalcin, osteoprotegerin (OPG), Runt-related transcription factor 2 (Runx2) and receptor activator of nuclear factor-kappa B ligand (RANKL) were also measured by real-time quantitative PCR. The JAK2-STAT3 pathway was evaluated by Western blot. RESULTS: Osteoblasts showed no obvious proliferation when treated with IL-17 and/or IFN-γ, but higher ALP activities were observed in primary osteoblasts treated with IL-17 or IL-17 + IFN-γ in induction medium. We also found that IL-17 could promote the gene expression of Alp, Runx2, Osteocalcin, Opg, and Rankl, while IFN-γ might attenuate this effect. Nevertheless, IL-17 and IFN-γ exhibited an inhibitory effect on the calcification of primary osteoblasts. We also found that IL-17 could directly facilitate RANKL expressions by JAK2-STAT3 pathway. CONCLUSION: The positive effects of IL-17 and IFN-γ on the early-stage differentiation and the negative effects on the calcification of murine calvarial osteoblasts contribute to our understanding of the role and interaction of inflammatory factors in the bone remodeling and as fundamental mechanisms involved in the destruction of alveolar bone.