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BACKGROUND: Predictive biomarkers of immune checkpoint inhibitor (ICI) efficacy are currently lacking for non-small cell lung cancer (NSCLC). Here, we describe the results from the Anti-PD-1 Response Prediction DREAM Challenge, a crowdsourced initiative that enabled the assessment of predictive models by using data from two randomized controlled clinical trials (RCTs) of ICIs in first-line metastatic NSCLC. METHODS: Participants developed and trained models using public resources. These were evaluated with data from the CheckMate 026 trial (NCT02041533), according to the model-to-data paradigm to maintain patient confidentiality. The generalizability of the models with the best predictive performance was assessed using data from the CheckMate 227 trial (NCT02477826). Both trials were phase III RCTs with a chemotherapy control arm, which supported the differentiation between predictive and prognostic models. Isolated model containers were evaluated using a bespoke strategy that considered the challenges of handling transcriptome data from clinical trials. RESULTS: A total of 59 teams participated, with 417 models submitted. Multiple predictive models, as opposed to a prognostic model, were generated for predicting overall survival, progression-free survival, and progressive disease status with ICIs. Variables within the models submitted by participants included tumor mutational burden (TMB), programmed death ligand 1 (PD-L1) expression, and gene-expression-based signatures. The best-performing models showed improved predictive power over reference variables, including TMB or PD-L1. CONCLUSIONS: This DREAM Challenge is the first successful attempt to use protected phase III clinical data for a crowdsourced effort towards generating predictive models for ICI clinical outcomes and could serve as a blueprint for similar efforts in other tumor types and disease states, setting a benchmark for future studies aiming to identify biomarkers predictive of ICI efficacy. TRIAL REGISTRATION: CheckMate 026; NCT02041533, registered January 22, 2014. CheckMate 227; NCT02477826, registered June 23, 2015.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/patologia , Antígeno B7-H1 , Biomarcadores TumoraisRESUMO
BACKGROUND/PURPOSE: Zirconia has been a popular material in dental implantology with good biocompatibility. But few research focused on its application in implant drills. This study aimed to investigate the physical, thermal, and biological effects on using the zirconia and stainless-steel drills for implant bone site preparation. METHODS: We performed a series of experiments to evaluate the physical wearing properties of zirconia and stainless-steel drills of identical diameter and similar shape. During the implant site preparation thermal test, we subjected both drills onto a resin-embedded bone, utilizing a thermal couple device without irrigation. Moreover, we conducted a cell study by collecting bone cells in vivo while preparing the implant site with both tested drills. The cell activity was evaluated through cell proliferation colorimetric analysis (XTT) and alkaline phosphatase (ALP) activity measurements. RESULTS: The zirconia drill outperforms the stainless-steel drill in terms of requiring less force, maintaining stability over repeated cutting tests, and generating lower temperatures during drilling (stainless-steel drill: 45.48 ± 1.31 °C; zirconia-coated drill: 32.98 ± 1.21 °C, P = 0.000247). Meanwhile, both types of drills show similar results in XTT colorimetric analysis and ALP activity test. CONCLUSION: The thermal effect study is more favorable for using the zirconia drill than the stainless-steel drill for bone preparation. Cytological analysis indicate that the zirconia drill produces a similar impact on bone cells activity as the stainless-steel drill. Therefore, we conclude that the zirconia drills offer a good cutting effect similar to currently available stainless-steel drills in various aspects.
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Aço Inoxidável , Zircônio , Animais , Teste de Materiais , Implantes Dentários , Proliferação de CélulasRESUMO
STATEMENT OF PROBLEM: Progressive peri-implant marginal bone loss and peri-implantitis have become a growing problem, but cross-sectional studies on their prevalence and risk factors are sparse. PURPOSE: The purpose of this cross-sectional clinical study was to investigate the prevalence of peri-implant marginal bone loss (MBL) and to identify systemic and local risk factors. MATERIAL AND METHODS: All adult patients who had received dental implants at the National Taiwan University Hospital (NTUH) during 2009 or 2010 were included. Their medical records were collected from the NTUH-integrative Medical Database. Consecutive follow-up radiographs were accessed for severity of MBL. The influence of each factor on MBL was estimated by using generalized estimating equations (GEEs). RESULTS: A total of 732 participants with 1873 implants were analyzed (mean follow-up: 5.30 years). The prevalence of MBL was 59.15% at the individual level and 49.55% at the implant level. The risk indicators identified for the presence of MBL were follow-up period of more than 2 years, diagnosis of diabetes within 12 months, radiation therapy (2 years after implant placement), implant location at maxillary canine (compared with mandibular molar), and implants from the Nobel Biocare brands (Brånemark System and NobelActive). A second multivariate GEE model confirmed the association of progressive MBL with implant location at the maxillary canine and mandibular incisor and implant brand or design. CONCLUSIONS: The identified risk indicators for MBL were longer follow-up period, diagnosis of diabetes, radiation therapy, implant location at maxillary canine, and implant brand or design.
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INTRODUCTION: CCN1 is an immediate-early gene product pivotal for arthritis progression. We have previously shown that sirtuin 6 (SIRT6) inhibited hypoxia-induced CCN1 expression in osteoblasts. Herein we examined the contribution of cyclic AMP-responsive element binding protein (CREB)/CRE to this suppressive action and the influence of CCN1 on cyclooxygenase (COX) 2 synthesis. MATERIALS AND METHODS: MC3T3-E1 murine osteoblasts were cultured under normoxia (21% oxygen) or hypoxia (2% oxygen). Expressions of CCN1, phospho-CREB (Ser133), COX2 and relevant kinases were assessed by Western blot. SIRT6 was overexpressed in cultured osteoblasts and arthritic joints by a lentiviral-based technique. Activities of CCN1 gene promoter constructs were examined by luciferase reporter assay. Interaction between CREB and CCN1 promoter was assessed by chromatin immunoprecipitation (ChIP). Collagen-induced arthritis (CIA) was established in 20 rats to evaluate the effects of SIRT6 therapy on osteoblastic expressions of phospho-CREB, CCN1 and COX2. RESULTS: SIRT6 suppressed hypoxia-enhanced CCN1 expression and CREB phosphorylation. Attenuation of calcium/calmodulin-dependent protein kinase II (CaMKII) may be responsible for SIRT6-induced CREB inhibition. CRE at - 286 bp upstream of the ATG start codon was essential for CCN1 expression under hypoxia and SIRT6 reduced hypoxia-stimulated CREB/CRE interaction. Forced expression of CREB rescued SIRT6-suppressed CCN1 synthesis. CCN1 induced COX2 expression in osteoblasts. In rat CIA, the therapeutic effect of SIRT6 was accompanied by decreases in osteoblastic expressions of phospho-CREB, CCN1 and COX2. CONCLUSION: Our study indicated that the benefits of SIRT6 to inflammatory arthritis and bone resorption are at least partially derived from its modulation of CREB/CCN1/COX2 pathway in osteoblasts.
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Artrite Experimental , Sirtuínas , Ratos , Camundongos , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/farmacologia , Osteoblastos/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/farmacologia , Hipóxia , Artrite Experimental/genética , Artrite Experimental/metabolismo , Fosforilação , Oxigênio/metabolismo , Oxigênio/farmacologia , Sirtuínas/metabolismo , Sirtuínas/farmacologia , AMP Cíclico/metabolismo , AMP Cíclico/farmacologiaRESUMO
INTRODUCTION: We have previously demonstrated that auxiliary metformin therapy promotes healing of apical periodontitis. Here we aimed to investigate the effects of metformin on osteoblast differentiation and osteoclast formation in cultured cells and rat apical periodontitis. METHODS: Murine pre-osteoblasts MC3T3-E1 and macrophages RAW264.7 were cultured under hypoxia (2% oxygen) or normoxia (21% oxygen) and stimulated with receptor activator of nuclear factor-κB ligand (RANKL) when indicated. Metformin was added to the cultures to evaluate its anti-hypoxic effects. Expressions of osteoblast differentiation regulator runt-related transcription factor 2 (RUNX2), RANKL, and osteoclast marker tartrate-resistant acid phosphatase (TRAP) were assessed by Western blot. Apical periodontitis was induced in mandibular first molars of 10 Sprague-Dawley rats. Root canal therapy with or without metformin supplement was performed. Periapical bone resorption was measured by micro-computed tomography. Immunohistochemistry was used to examine RUNX2, RANKL, and TRAP expressions. RESULTS: Hypoxia suppressed RUNX2 expression and enhanced RANKL synthesis in pre-osteoblasts. TRAP production increased in macrophages after hypoxia and/or RANKL stimulation. Metformin reversed hypoxia-induced RUNX2 suppression and RANKL synthesis in pre-osteoblasts. Metformin also inhibited hypoxia and RANKL-enhanced TRAP synthesis in macrophages. Intracanal metformin diminished bone loss in rat apical periodontitis. Comparing with vehicle control, cells lining bone surfaces in metformin-treated lesions had significantly stronger expression of RUNX2 and decreased synthesis of RANKL and TRAP. CONCLUSIONS: Alleviation of bone resorption by intracanal metformin was associated with enhanced osteoblast differentiation and diminished osteoclast formation in rat apical periodontitis. Our results endorsed the role of metformin as an effective medicament for inflammatory bone diseases.
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Reabsorção Óssea , Metformina , Periodontite Periapical , Ratos , Camundongos , Animais , Osteoclastos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Microtomografia por Raio-X , Ratos Sprague-Dawley , Reabsorção Óssea/metabolismo , Osteoblastos , Periodontite Periapical/patologia , Diferenciação Celular , Hipóxia/metabolismo , Oxigênio/metabolismo , Ligante RANK/metabolismoRESUMO
AIM: Biallelic loss-of-function FAM20A mutations cause amelogenesis imperfecta (AI) type IG, better known as enamel renal syndrome (ERS), characterized by severe enamel hypoplasia, delayed/failed tooth eruption, intrapulpal calcifications, gingival hyperplasia and nephrocalcinosis. FAM20A binds to FAM20C, the Golgi casein kinase (GCK) and potentiates its function to phosphorylate secreted proteins critical for biomineralization. While many FAM20A pathogenic mutations have been reported, the pathogeneses of orodental anomalies in ERS remain to be elucidated. This study aimed to identify disease-causing mutations for patients with ERS phenotypes and to discern the molecular mechanism underlying ERS intrapulpal calcifications. METHODOLOGY: Phenotypic characterization and whole exome analyses were conducted for 8 families and 2 sporadic cases with hypoplastic AI. A minigene assay was performed to investigate the molecular consequences of a FAM20A splice-site variant. RNA sequencing followed by transcription profiling and gene ontology (GO) analyses were carried out for dental pulp tissues of ERS and the control. RESULTS: Biallelic FAM20A mutations were demonstrated for each affected individual, including 7 novel pathogenic variants: c.590-5T>A, c.625T>A (p.Cys209Ser), c.771del (p.Gln258Argfs*28), c.832_835delinsTGTCCGACGGTGTCCGACGGTGTC CA (p.Val278Cysfs*29), c.1232G>A (p.Arg411Gln), c.1297A>G (p.Arg433Gly) and c.1351del (p.Gln451Serfs*4). The c.590-5T>A splice-site mutation caused Exon 3 skipping, which resulted in an in-frame deletion of a unique region of the FAM20A protein, p.(Asp197_Ile214delinsVal). Analyses of differentially expressed genes in ERS pulp tissues demonstrated that genes involved in biomineralization, particularly dentinogenesis, were significantly upregulated, such as DSPP, MMP9, MMP20 and WNT10A. Enrichment analyses indicated overrepresentation of gene sets associated with BMP and SMAD signalling pathways. In contrast, GO terms related to inflammation and axon development were underrepresented. Among BMP signalling genes, BMP agonists GDF7, GDF15, BMP3, BMP8A, BMP8B, BMP4 and BMP6 were upregulated, while BMP antagonists GREM1, BMPER and VWC2 showed decreased expression in ERS dental pulp tissues. CONCLUSIONS: Upregulation of BMP signalling underlies intrapulpal calcifications in ERS. FAM20A plays an essential role in pulp tissue homeostasis and prevention of ectopic mineralization in soft tissues. This critical function probably depends upon MGP (matrix Gla protein), a potent mineralization inhibitor that must be properly phosphorylated by FAM20A-FAM20C kinase complex.
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Amelogênese Imperfeita , Calcinose , Proteínas do Esmalte Dentário , Nefrocalcinose , Humanos , Nefrocalcinose/genética , Nefrocalcinose/patologia , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/metabolismo , Amelogênese Imperfeita/patologia , Polpa Dentária/metabolismo , Proteínas do Esmalte Dentário/genética , Mutação , Perfilação da Expressão Gênica , Proteínas de Transporte/genéticaRESUMO
Current rat alveolar ridge preservation models have not been well standardized. In this study, we proposed decoronation-induced infected alveolar socket model of rat. The bilateral maxillary first molars (M1) of twenty-four rats were decoronized or extracted. After 2, 6, 10, and 14 weeks, bone and soft tissue changes at M1 and periodontal conditions of maxillary second (M2) and third molars (M3) were evaluated by micro-computed tomography and histological analysis. Additional eighteen rats with standardized size defects were grafted with Bio-Oss Collagen to compare with unmanipulated contralateral side. Decoronation preserved greater bone and soft tissue dimensions at M1, provided larger three-dimensional (3D) bone contour volume, but also promoted periodontal breakdown of M2 Histological results showed intense inflammatory cell infiltrations and severe bone resorption within M1 socket and at mesial aspect of M2. The critical dimensions to accommodate largest standardized defect at M1 were 2.2-2.3 mm at vertical bone height and 2.8-3.2 mm at alveolar crestal width. Bio-Oss Collagen could not fully preserve buccal or palatal bone height but could be beneficial in preserving ridge width in large alveolar defects. Collectively, if periodontally-involved alveolar bone defect is preferred, we suggest extracting M1 roots 6 weeks after decoronation to allow periodontitis to occur at M2. If standardized critical dimension defect is preferred, we suggest extracting M1 roots 2 weeks after decoronation, and creating defect in the middle of M1 site with size no larger than 2.7 mm diameter to its full depth.
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Perda do Osso Alveolar , Processo Alveolar , Alvéolo Dental , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/patologia , Processo Alveolar/diagnóstico por imagem , Processo Alveolar/patologia , Animais , Colágeno/uso terapêutico , Minerais , Ligamento Periodontal/patologia , Ratos , Extração Dentária , Microtomografia por Raio-XRESUMO
In this study, we fabricated gelatin/nano-hydroxyapatite/metformin scaffold (GHMS) and compared its effectiveness in bone regeneration with extraction-only, Sinbone, and Bio-Oss Collagen® groups in a critical size rat alveolar bone defect model. GHMS was synthesized by co-precipitating calcium hydroxide and orthophosphoric acid within gelatin solution, incorporating metformin, and cross-linked by microbial transglutaminase. The morphology, characterization, and biocompatibility of scaffold were examined. The in vitro effects of GHMS on osteogenic gene and protein expressions were evaluated. In vivo bone formation was assessed in a critical size rat alveolar bone defect model with micro-computed tomography and histological examination by comparing GHMS with extraction-only, Sinbone, and Bio-Oss Collagen®. The synthesized GHMS had a highly interconnected porous structure with a mean pore size of 81.85 ± 13.8 µm. GHMS exhibited good biocompatibility; promoted ALPL, RUNX2, SP7, BGLAP, SPARC and Col1a1 gene expressions; and upregulated the synthesis of osteogenic proteins, including osteonectin, osteocalcin, and collagen type I. In critical size rat alveolar bone defects, GHMS showed superior bone regeneration compared to extraction-only, Sinbone, and Bio-Oss Collagen® groups as manifested by greater alveolar ridge preservation, while more bone formation with a lower percentage of connective tissue and residual scaffold at the defect sites grafted with GHMS in histological staining. The GHMS presented in this study may be used as a potential bone substitute to regenerate alveolar bone. The good biocompatibility, relatively fast degradation, interconnected pores allowing vascularization, and higher bioactivity properties of the components of the GHMS (gelatin, nHA, and metformin) may contribute to direct osteogenesis.
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Regeneração Óssea , Durapatita , Gelatina , Regeneração Tecidual Guiada , Metformina/administração & dosagem , Nanocompostos , Alicerces Teciduais , Animais , Materiais Biocompatíveis/química , Biomarcadores , Fenômenos Químicos , Durapatita/química , Gelatina/química , Regeneração Tecidual Guiada/métodos , Imuno-Histoquímica , Minerais , Modelos Animais , Nanocompostos/química , Nanocompostos/ultraestrutura , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Ratos , Engenharia Tecidual , Alicerces Teciduais/química , Microtomografia por Raio-XRESUMO
Automatic craniomaxillofacial (CMF) landmark localization from cone-beam computed tomography (CBCT) images is challenging, considering that 1) the number of landmarks in the images may change due to varying deformities and traumatic defects, and 2) the CBCT images used in clinical practice are typically large. In this paper, we propose a two-stage, coarse-to-fine deep learning method to tackle these challenges with both speed and accuracy in mind. Specifically, we first use a 3D faster R-CNN to roughly locate landmarks in down-sampled CBCT images that have varying numbers of landmarks. By converting the landmark point detection problem to a generic object detection problem, our 3D faster R-CNN is formulated to detect virtual, fixed-size objects in small boxes with centers indicating the approximate locations of the landmarks. Based on the rough landmark locations, we then crop 3D patches from the high-resolution images and send them to a multi-scale UNet for the regression of heatmaps, from which the refined landmark locations are finally derived. We evaluated the proposed approach by detecting up to 18 landmarks on a real clinical dataset of CMF CBCT images with various conditions. Experiments show that our approach achieves state-of-the-art accuracy of 0.89 ± 0.64mm in an average time of 26.2 seconds per volume.
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Tomografia Computadorizada de Feixe Cônico , Imageamento TridimensionalRESUMO
OBJECTIVE: To estimate a patient-specific reference bone shape model for a patient with craniomaxillofacial (CMF) defects due to facial trauma. METHODS: We proposed an automatic facial bone shape estimation framework using pre-traumatic conventional portrait photos and post-traumatic head computed tomography (CT) scans via a 3D face reconstruction and a deformable shape model. Specifically, a three-dimensional (3D) face was first reconstructed from the patient's pre-traumatic portrait photos. Second, a correlation model between the skin and bone surfaces was constructed using a sparse representation based on the CT images of training normal subjects. Third, by feeding the reconstructed 3D face into the correlation model, an initial reference shape model was generated. In addition, we refined the initial estimation by applying non-rigid surface matching between the initially estimated shape and the patient's post-traumatic bone based on the adaptive-focus deformable shape model (AFDSM). Furthermore, a statistical shape model, built from the training normal subjects, was utilized to constrain the deformation process to avoid overfitting. RESULTS AND CONCLUSION: The proposed method was evaluated using both synthetic and real patient data. Experimental results show that the patient's abnormal facial bony structure can be recovered using our method, and the estimated reference shape model is considered clinically acceptable by an experienced CMF surgeon. SIGNIFICANCE: The proposed method is more suitable to the complex CMF defects for CMF reconstructive surgical planning.
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Processamento de Imagem Assistida por Computador , Modelos Estatísticos , Face/diagnóstico por imagem , Face/cirurgia , Humanos , Imageamento Tridimensional , Tomografia Computadorizada por Raios XRESUMO
Oral cancer (OC) is a serious health problem. Surgery is the best method to treat the disease but might reduce the quality of life of patients. Photodynamic therapy (PDT) may enhance quality of life but with some limitations. Therefore, the development of a new strategy to facilitate PDT effectiveness has become crucial. ATP-binding cassette G2 (ABCG2) is a membrane protein-associated drug resistance and stemness in cancers. Here, we examined whether ABCG2 plays an important role in regulating the treatment efficacy of PDT and whether ABCG2 inhibition by natural compounds can promote the effect of PDT in OC cells. Several head and neck cancer cells were utilized in this study. OECM1 and SAS cells were selected to investigate the relationship between ABCG2 expression and protoporphyrin IX (PpIX) accumulation. Western blot analysis, flow cytometry analysis, and survival probability were performed to determine PDT efficacy and cellular stemness upon treatment of different dietary compounds, including epigallocatechin gallate (EGCG) and curcumin. In this study, we found that ABCG2 expression varied in OC cells. Hypoglycemic culture for SAS cells enhanced ABCG2 expression as higher ABCG2 expression was associated with lower PpIX accumulation and cellular stemness in OC cells. In contrast, suppression of ABCG2 expression by curcumin and tea polyphenol EGCG led to greater PpIX accumulation and enhanced PDT treatment efficiency in OC cells. In conclusion, ABCG2 plays an important role in regulating the effect of PDT. Change in glucose concentration and treatment with natural compounds modulated ABCG2 expression, resulting in altered PDT efficacy for OC cells. These modulations raise a potential new treatment strategy for early-stage OCs.
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Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Catequina/análogos & derivados , Curcumina/farmacologia , Gefitinibe/farmacologia , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Catequina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Estimativa de Kaplan-Meier , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologiaRESUMO
This report provides three-phase concept for treating skeletal Class III growing patients with severe space deficiency. Three cases are presented. All had received miniplate-anchored facemask treatment and followed till near completion of growth. Infrazygomatic miniplates were used for both facemask protraction and distalization of the dentition to relieve crowding. With the aid of bone-anchored facemask, maxillary protraction may be continued independent of the orthodontic tooth movement even in late postpubertal growth peak stage. With cephalometric superimpositions using the structural method, we have demonstrated how vertical dental change could affect the skeletal changes and overall clinical outcomes. The persistent mandibular growth during pubertal growth spurt plays a main role in decreasing the effects of maxillary protraction. To keep up with the mandibular growth, we recommend using skeletally anchored facemask long-term till the end of growth spurt. Applying maxillary protraction from infrazygomatic miniplates exposed at the molar area has the merits that it avoids unwanted palatal rotation and that the miniplates maybe used as orthodontic anchorage when indicated. We emphasize the importance of planning the treatment contemplating the skeletal developmental stage and the completion of dental arches. This prolonged orthopedic treatment may contribute to greater long-term effects and stability.
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Aparelhos de Tração Extrabucal , Má Oclusão Classe III de Angle/terapia , Desenho de Aparelho Ortodôntico , Técnicas de Movimentação Dentária/instrumentação , Cefalometria/métodos , Criança , Feminino , Humanos , Masculino , Mandíbula/patologia , Maxila/patologia , Dente Molar/patologia , Procedimentos de Ancoragem Ortodôntica/instrumentaçãoRESUMO
Accurate bone segmentation and anatomical landmark localization are essential tasks in computer-aided surgical simulation for patients with craniomaxillofacial (CMF) deformities. To leverage the complementarity between the two tasks, we propose an efficient end-to-end deep network, i.e., multi-task dynamic transformer network (DTNet), to concurrently segment CMF bones and localize large-scale landmarks in one-pass from large volumes of cone-beam computed tomography (CBCT) data. Our DTNet was evaluated quantitatively using CBCTs of patients with CMF deformities. The results demonstrated that our method outperforms the other state-of-the-art methods in both tasks of the bony segmentation and the landmark digitization. Our DTNet features three main technical contributions. First, a collaborative two-branch architecture is designed to efficiently capture both fine-grained image details and complete global context for high-resolution volume-to-volume prediction. Second, leveraging anatomical dependencies between landmarks, regionalized dynamic learners (RDLs) are designed in the concept of "learns to learn" to jointly regress large-scale 3D heatmaps of all landmarks under limited computational costs. Third, adaptive transformer modules (ATMs) are designed for the flexible learning of task-specific feature embedding from common feature bases.
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The development of a novel alloplastic graft with both osteoinductive and osteoconductive properties is still necessary. In this study, we tried to synthesize a biomimetic hydroxyapatite microspheres (gelatin/nano-hydroxyapatite microsphere embedded with stromal cell-derived factor-1: GHM-S) from nanocrystalline hydroxyapatites and to investigate their therapeutic potential and effects on bone regeneration. In this study, hydroxyapatite was synthesized by co-precipitation of calcium hydroxide and orthophosphoric acid to gelatin solution. The microbial transglutaminase was used as the agent to crosslink the microspheres. The morphology, characterization, and thermal gravimetric analysis of microspheres were performed. SDF-1 release profile and in vitro biocompatibility and relative osteogenic gene expression were analyzed, followed by in vivo micro-computed tomography study and histological analysis. The synthesized hydroxyapatite was found to be similar to hydroxyapatite of natural bone tissue. The stromal cell-derived factor-1 was embedded into gelatin/hydroxyapatite microsphere to form the biomimetic hydroxyapatite microsphere. The stromal cell-derived factor-1 protein could be released in a controlled manner from the biomimetic hydroxyapatite microsphere and form a concentration gradient in the culture environment to attract the migration of stem cells. Gene expression and protein expression indicated that stem cells could differentiate or develop into pre-osteoblasts. The effect of bone formation by the biomimetic hydroxyapatite microsphere was assessed by an in vivo rats' alveolar bone defects model and confirmed by micro-CT imaging and histological examination. Our findings demonstrated that the biomimetic hydroxyapatite microsphere can enhance the alveolar bone regeneration. This design has potential be applied to other bone defects.
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Materiais Biomiméticos/química , Regeneração Óssea/efeitos dos fármacos , Durapatita/química , Nanocompostos/química , Animais , Materiais Biomiméticos/farmacologia , Células Cultivadas , Quimiocina CXCL12/administração & dosagem , Quimiocina CXCL12/farmacologia , Gelatina/química , Humanos , Microesferas , RatosRESUMO
BACKGROUND/PURPOSE: Students with different undergraduate trainings may have different responses after taking a combined course with both clinical and basic topics. This study investigated the learning experience of basic science and clinical dentistry by postgraduate students in Institute of Clinical Dentistry (ICD) and Institute of Oral Biology (IOB) after finishing the specific course. MATERIALS AND METHODS: Semi-structure questionnaire filled by internet process was used. The data were collected and analyzed statistically. RESULTS: Nineteen participants who took the course of "panel discussion of oral oncology" since 2014 to 2018 were included in this study. Of the 19 postgraduate students, 11 were from ICD and 8 from IOB. Both ICD and IOB students gave high scores for the items such as benefit for the research, appropriateness of the discussion topics, and suitableness of problem-based teaching model. ICD students tended to have better fitness of interdisciplinary learning (Pâ¯>â¯0.05), better understanding of clinical topics (significant, Pâ¯=â¯0.02), and a higher willing to recommend other students to take the course (Pâ¯>â¯0.05) than IOB students. However, IOB students tended to have a better understanding of basic science topics than ICD students, although the difference was not significant (Pâ¯>â¯0.05). CONCLUSION: Our problem-based and constructive teaching course and the selected topics are proper and helpful for students' future research. The students with the clinical training background are prone to have better understanding of clinical topics, while those with the basic science training tend to have better understanding of basic science topics.
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BACKGROUND AND OBJECTIVE: Biallelic loss-of-function mutations of human FAM20A have been known to cause enamel-renal syndrome (ERS), featured by agenesis of dental enamel, nephrocalcinosis, and other orodental abnormalities, including gingival hyperplasia. However, while the histopathology of this gingival anomaly has been analyzed, its underlying molecular mechanism remains largely unknown. This study aimed to unravel the pathogenesis of gingival hyperplasia in ERS. METHODS: Whole-exome sequencing was conducted for an ERS case. Transcriptome analyses, using RNA sequencing, of the patient's gingiva were performed to unravel dysregulated molecules and aberrant biological processes underlying the gingival pathology of ERS, which was further confirmed by histology and immunohistochemistry. RESULTS: Two novel frameshift FAM20A mutations in Exon 1 (g.5417delG; c.129delG; p.Cys44Alafs*101) and Exon 5 (g.62248_62249delAG; c.734_735delAG; p.Glu245Glyfs*11) were identified. Transcriptional profiling of patient's gingival tissue revealed a total of 1683 genes whose expression had increased (1129 genes) or decreased (554 genes) at least 2-fold compared to control gingival tissues. There were 951 gene ontology (GO) terms of biological process being significantly over-represented or under-represented. While GOs involved in extracellular matrix organization, angiogenesis, biomineralization, and epithelial cell proliferation appeared to be activated in ERS gingiva, genes related to keratinocyte differentiation, epithelial development, and keratinization were of decreased expression. FAM20A immunohistochemistry revealed a strong reactivity at the suprabasal layers of epithelium in control gingiva but showed a significantly diminished and scattered signal in ERS tissues. For genes showing significant over-expression in the transcriptome analyses, namely ALPL, SPARC, and ACTA2, an increased immunoreactivity was observed. CONCLUSION: Our results unraveled a potential role for FAM20A in homeostasis of both gingival epithelium and connective tissues.
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Amelogênese Imperfeita/genética , Proteínas do Esmalte Dentário/genética , Gengiva/metabolismo , Nefrocalcinose/genética , Transcriptoma , Adulto , Mutação da Fase de Leitura , Perfilação da Expressão Gênica , Humanos , MasculinoRESUMO
Flowering time is a major determinant of the local adaptation of plants. Although numerous loci affecting flowering time have been mapped in maize, their underlying molecular mechanisms and roles in adaptation remain largely unknown. Here, we report the identification and characterization of MADS-box transcription factor ZmMADS69 that functions as a flowering activator through the ZmRap2.7-ZCN8 regulatory module and contributes to adaptation. We show that ZmMADS69 underlies a quantitative trait locus controlling the difference in flowering time between maize and its wild ancestor, teosinte. Maize ZmMADS69 allele is expressed at a higher level at floral transition and confers earlier flowering than the teosinte allele under long days and short days. Overexpression of ZmMADS69 causes early flowering, while a transposon insertion mutant of ZmMADS69 exhibits delayed flowering. ZmMADS69 shows pleiotropic effects for multiple traits of agronomic importance. ZmMADS69 functions upstream of the flowering repressor ZmRap2.7 to downregulate its expression, thereby relieving the repression of the florigen gene ZCN8 and causing early flowering. Population genetic analyses showed that ZmMADS69 was a target of selection and may have played an important role as maize spread from the tropics to temperate zones. Our findings provide important insights into the regulation and adaptation of flowering time.
Assuntos
Flores/fisiologia , Proteínas de Domínio MADS/metabolismo , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Adaptação Fisiológica/genética , Mapeamento Cromossômico , Florígeno , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Genética Populacional , Proteínas de Domínio MADS/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Locos de Características Quantitativas , Seleção Genética , Zea mays/genéticaRESUMO
BACKGROUND/PURPOSE: Extraction of the third molar may cause post-operative complications. This study assessed whether application of pure type-1 collagen to the third molar extraction socket can reduce post-operative pain score and duration and promote socket bone healing. METHODS: Fourteen patients who underwent 20 bilateral and symmetric third molar extractions were included in this study. After two tooth extractions at two different occasions in the same patient, one socket was filled with pure type-1 collagen (experimental group, n = 20) and the other socket received nothing but the blood clot (control group, n = 20). The post-operative pain score and duration, mouth-opening limitation, and the bone density at the socket site were assessed at weeks 1, 2, 4, and 8 after tooth extraction. RESULTS: Patients in the experimental group had a significantly lower mean post-operative pain score (2.6 ± 1.2) than patients in the control group (4.7 ± 2.0), and had a significantly shorter post-operative pain duration (2.7 ± 1.4 days) than patients in the control group (3.7 ± 1.8 days). We also observed a significantly lower frequency of mouth-opening limitation in 20 experimental-group patients (45%) than in 20 control-group patients (90%, P = 0.007). Moreover, a significantly higher mineralization ratio (10.2%) was found in the experimental socket site than in the control socket site. CONCLUSION: Application of pure type-1 collagen to the third molar extraction socket can reduce post-operative pain score and duration, decrease the frequency of mouth-opening limitation, and increase mineralization ratio at the extraction socket site.
Assuntos
Materiais Biocompatíveis/administração & dosagem , Colágeno Tipo I/administração & dosagem , Dente Serotino/cirurgia , Dor Pós-Operatória/prevenção & controle , Extração Dentária/efeitos adversos , Adolescente , Adulto , Feminino , Humanos , Masculino , Mandíbula/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Taiwan , Dente Impactado/cirurgia , Técnicas de Fechamento de Ferimentos , Cicatrização , Adulto JovemRESUMO
BACKGROUND: Genetic data for traditional Taiwanese (Formosan) agriculture is essential for tracing the origins on the East Asian mainland of the Austronesian language family, whose homeland is generally placed in Taiwan. Three main models for the origins of the Taiwanese Neolithic have been proposed: origins in coastal north China (Shandong); in coastal central China (Yangtze Valley), and in coastal south China. A combination of linguistic and agricultural evidence helps resolve this controversial issue. RESULTS: We report on botanically informed linguistic fieldwork of the agricultural vocabulary of Formosan aborigines, which converges with earlier findings in archaeology, genetics and historical linguistics to assign a lesser role for rice than was earlier thought, and a more important one for the millets. We next present the results of an investigation of domestication genes in a collection of traditional rice landraces maintained by the Formosan aborigines over a hundred years ago. The genes controlling awn length, shattering, caryopsis color, plant and panicle shapes contain the same mutated sequences as modern rice varieties everywhere else in the world, arguing against an independent domestication in south China or Taiwan. Early and traditional Formosan agriculture was based on foxtail millet, broomcorn millet and rice. We trace this suite of cereals to northeastern China in the period 6000-5000 BCE and argue, following earlier proposals, that the precursors of the Austronesians, expanded south along the coast from Shandong after c. 5000 BCE to reach northwest Taiwan in the second half of the 4th millennium BCE. This expansion introduced to Taiwan a mixed farming, fishing and intertidal foraging subsistence strategy; domesticated foxtail millet, broomcorn millet and japonica rice; a belief in the sacredness of foxtail millet; ritual ablation of the upper incisors in adolescents of both sexes; domesticated dogs; and a technological package including inter alia houses, nautical technology, and loom weaving. CONCLUSION: We suggest that the pre-Austronesians expanded south along the coast from that region after c. 5000 BCE to reach northwest Taiwan in the second half of the 4th millennium BCE.