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1.
Eur J Orthod ; 44(1): 43-50, 2022 01 25.
Article in English | MEDLINE | ID: mdl-33950251

ABSTRACT

BACKGROUND: Previous studies embracing digital technology and automated methods of scoring dental arch relationships have shown that such technology is valid and accurate. To date, however there is no published literature on artificial intelligence and machine learning to completely automate the process of dental landmark recognition. OBJECTIVES: This study aimed to develop and evaluate a fully automated system and software tool for the identification of landmarks on human teeth using geometric computing, image segmenting, and machine learning technology. METHODS: Two hundred and thirty-nine digital models were used in the automated landmark recognition (ALR) validation phase, 161 of which were digital models from cleft palate subjects aged 5 years. These were manually annotated to facilitate qualitative validation. Additionally, landmarks were placed on 20 adult digital models manually by 3 independent observers. The same models were subjected to scoring using the ALR software and the differences (in mm) were calculated. All the teeth from the 239 models were evaluated for correct recognition by the ALR with a breakdown to find which stages of the process caused the errors. RESULTS: The results revealed that 1526 out of 1915 teeth (79.7%) were correctly identified, and the accuracy validation gave 95% confidence intervals for the geometric mean error of [0.285, 0.317] for the humans and [0.269, 0.325] for ALR-a negligible difference. CONCLUSIONS/IMPLICATIONS: It is anticipated that ALR software tool will have applications throughout clinical dentistry and anthropology, and in research will constitute an accurate and objective tool for handling large datasets without the need for time intensive employment of experts to place landmarks manually.


Subject(s)
Cleft Palate , Tooth , Adult , Artificial Intelligence , Child, Preschool , Humans , Reproducibility of Results , Software
2.
Ann Rheum Dis ; 71(12): 2035-43, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22679299

ABSTRACT

OBJECTIVES: To investigate convergence of endoplasmic reticulum stress pathways and enhanced reactive oxygen species (ROS) production, due to intracellular retention of mutant tumour necrosis factor receptor 1 (TNFR1), as a disease mechanism in TNFR-associated periodic syndrome (TRAPS). METHODS: Peripheral blood mononuclear cells from patients with TRAPS (n=16) and healthy controls (HC) (n=22) were studied alongside HEK293T cells expressing wild type-TNFR1 or TRAPS-associated mutations. Unfolded protein response (UPR)-associated proteins (protein kinase-like endoplasmic reticulum kinase, PERK), phosphorylated-PERK (p-PERK), phosphorylated inositol-requiring enzyme 1α (p-IRE1α) and spliced X-box binding protein 1 (sXBP1)) were measured by flow cytometry. XBP1 splicing and UPR-associated transcript expression were assessed by reverse transcription PCR/quantitative real-time PCR. ROS levels were measured using CM-H(2)DCFDA and MitoSOX Red in patients' monocytes or HEK293T cells by flow cytometry. RESULTS: Mutant TNFR1-expressing HEK293T cells had increased TNFR1 expression associated with intracellular aggregation. TRAPS patients had increased sXBP1 transcripts (p<0.01) compared with HC. Raised p-PERK protein was seen, indicative of an UPR, but other UPR-associated transcripts were normal. Increased ROS levels were observed in TRAPS monocytes compared with HCs (p<0.02); these increased further upon IL-6 stimulation (p<0.01). Lipopolysaccharide-stimulated peripheral blood mononuclear cells of patients with TRAPS, but not HCs, demonstrated increased sXBP1 levels (p<0.01), which were reduced by antioxidant treatment (p<0.05). CONCLUSIONS: Patients with TRAPS have evidence of increased sXBP1 and PERK expression but without other signs of classical UPR, and also with high ROS generation that may contribute to the pro-inflammatory state associated with TRAPS. The authors propose a non-traditional XBP1 pathway with enhanced sXBP1 as a novel disease-contributing mechanism in TRAPS.


Subject(s)
DNA-Binding Proteins/metabolism , Endoplasmic Reticulum Stress/physiology , Hereditary Autoinflammatory Diseases/metabolism , Reactive Oxygen Species/metabolism , Transcription Factors/metabolism , Tumor Necrosis Factor-alpha/metabolism , Adolescent , Adult , Aged , Alternative Splicing/physiology , Antioxidants/metabolism , Antioxidants/pharmacology , DNA-Binding Proteins/genetics , Female , HEK293 Cells , Hereditary Autoinflammatory Diseases/genetics , Humans , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Lipopolysaccharides/pharmacology , Male , Middle Aged , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type I/metabolism , Regulatory Factor X Transcription Factors , Transcription Factors/genetics , Unfolded Protein Response/physiology , X-Box Binding Protein 1 , Young Adult , eIF-2 Kinase/metabolism
3.
F1000 Med Rep ; 22010 Jan 18.
Article in English | MEDLINE | ID: mdl-20948856

ABSTRACT

The concept of autoinflammatory disease as a new disease classification has resulted in a paradigm shift in our understanding of the the broad spectrum of immunological diseases. The effectiveness of interleukin-1 blockade in a variety of disorders has resulted in a marked reduction in suffering for many of these patients.

4.
J Mol Biol ; 394(5): 905-21, 2009 Dec 18.
Article in English | MEDLINE | ID: mdl-19835883

ABSTRACT

IL-17A is a pro-inflammatory cytokine produced by the newly identified Th17 subset of T-cells. We have isolated a human monoclonal antibody to IL-17A (CAT-2200) that can potently neutralize the effects of recombinant and native human IL-17A. We determined the crystal structure of IL-17A in complex with the CAT-2200 Fab at 2.6 A resolution in order to provide a definitive characterization of the epitope and paratope regions. Approximately a third of the IL-17A dimer is disordered in this crystal structure. The disorder occurs in both independent copies of the complex in the asymmetric unit and does not appear to be influenced by crystal packing. The complex contains one IL-17A dimer sandwiched between two CAT-2200 Fab fragments. The IL-17A is a disulfide-linked homodimer that is similar in structure to IL-17F, adopting a cystine-knot fold. The structure is not inconsistent with the previous prediction of a receptor binding cavity on IL-17 family members. The epitope recognized by CAT-2200 is shown to involve 12 amino acid residues from the quaternary structure of IL-17A, with each Fab contacting both monomers in the dimer. All complementarity-determining regions (CDRs) in the Fab contribute to a total of 16 amino acid residues in the antibody paratope. In vitro affinity optimization was used to generate CAT-2200 from a parental lead antibody using random mutagenesis of CDR3 loops. This resulted in seven amino acid changes (three in VL-CDR3 and four in VH-CDR3) and gave an approximate 30-fold increase in potency in a cell-based neutralization assay. Two of the seven amino acids form part of the CAT-2200 paratope. The observed interaction site between CAT-2200 and IL-17A is consistent with data from hydrogen/deuterium exchange mass spectrometry and mutagenesis approaches.


Subject(s)
Antibodies, Neutralizing/chemistry , Interleukin-17/chemistry , Amino Acid Substitution , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/metabolism , Antibodies, Neutralizing/metabolism , Antibody Affinity , Binding Sites, Antibody , Crystallography, X-Ray , Dimerization , Directed Molecular Evolution , Epitopes/chemistry , Humans , Interleukin-17/metabolism , Models, Molecular , Mutagenesis , Mutation, Missense , Protein Binding , Protein Structure, Quaternary
5.
Pediatr Res ; 65(5 Pt 2): 38R-45R, 2009 May.
Article in English | MEDLINE | ID: mdl-19190531

ABSTRACT

Historically, pediatric inflammatory diseases were viewed as autoimmune but developments in genetics of monogenic disease have supported our proposal that "inflammation against self" be viewed as an immunologic disease continuum (IDC), with genetic disorders of adaptive and innate immunity at either end. Innate immune-mediated diseases may be associated with significant tissue destruction without evident adaptive immune responses and are designated as autoinflammatory due to distinct immunopathologic features. However, the majority of pediatric inflammatory disorders are situated along this IDC. Innate immunity has been demonstrated in polygenic disorders, particularly Crohn's disease (CD). A genetic overlap exists between CD and some major histocompatibility complex (MHC) class I-associated diseases, including psoriasis; these diseases seem to represent a true intermediate between autoinflammation and autoimmunity. Conversely, classical autoimmune diseases, with autoantibody and MHC class II associations, including celiac disease and rheumatoid arthritis (RA), have adaptive immune genetic associations, including Cytotoxic T-Lymphocyte Antigen-4 (CTLA4) and PTPN22. This proposed classification is clinically relevant, because innate immune-mediated disorders may respond to cytokine antagonism whereas autoimmune-mediated diseases respond better to anti-T and B cell therapies. Furthermore, the etiopathogenesis of poorly defined "autoimmune" diseases, such as juvenile idiopathic arthritis, may be inferred to have substantial innate immune involvement, based on response to IL-1 antagonism.


Subject(s)
Immune System Diseases/immunology , Inflammation/classification , Adaptation, Physiological/immunology , Child , Humans , Immunity, Innate , Inflammation/immunology
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