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1.
Genesis ; 57(6): e23297, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30974046

RESUMO

Src64 is required for actomyosin contraction during cellularization of the Drosophila embryonic blastoderm. The mechanism of actomyosin ring constriction is poorly understood even though a number of cytoskeletal regulators have been implicated in the assembly, organization, and contraction of these microfilament rings. How these cytoskeletal processes are regulated during development is even less well understood. To investigate the role of Src64 as an upstream regulator of actomyosin contraction, we conducted a proteomics screen to identify proteins whose expression levels are controlled by src64. Global levels of actin are reduced in src64 mutant embryos. Furthermore, we show that reduction of the actin isoform Actin 5C causes defects in actomyosin contraction during cellularization similar to those caused by src64 mutation, indicating that a relatively high level of Actin 5C is required for normal actomyosin contraction and furrow canal structure. However, reduction of Actin 5C levels only slows down actomyosin ring constriction rather than preventing it, suggesting that src64 acts not only to modulate actin levels, but also to regulate the actomyosin cytoskeleton by other means.


Assuntos
Actomiosina/fisiologia , Proteínas de Drosophila/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Actomiosina/metabolismo , Animais , Citoesqueleto/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Embrião não Mamífero/metabolismo , Proteínas dos Microfilamentos/metabolismo , Morfogênese/genética , Mutação , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/fisiologia , Proteômica/métodos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia
2.
J Dent ; 147: 105105, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38821394

RESUMO

OBJECTIVES: This study aimed to assess the reliability of AI-based system that assists the healthcare processes in the diagnosis of caries on intraoral radiographs. METHODS: The proximal surfaces of the 323 selected teeth on the intraoral radiographs were evaluated by two independent observers using an AI-based (Diagnocat) system. The presence or absence of carious lesions was recorded during Phase 1. After 4 months, the AI-aided human observers evaluated the same radiographs (Phase 2), and the advanced convolutional neural network (CNN) reassessed the radiographic data (Phase 3). Subsequently, data reflecting human disagreements were excluded (Phase 4). For each phase, the Cohen and Fleiss kappa values, as well as the sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy of Diagnocat, were calculated. RESULTS: During the four phases, the range of Cohen kappa values between the human observers and Diagnocat were κ=0.66-1, κ=0.58-0.7, and κ=0.49-0.7. The Fleiss kappa values were κ=0.57-0.8. The sensitivity, specificity and diagnostic accuracy values ranged between 0.51-0.76, 0.88-0.97 and 0.76-0.86, respectively. CONCLUSIONS: The Diagnocat CNN supports the evaluation of intraoral radiographs for caries diagnosis, as determined by consensus between human and AI system observers. CLINICAL SIGNIFICANCE: Our study may aid in the understanding of deep learning-based systems developed for dental imaging modalities for dentists and contribute to expanding the body of results in the field of AI-supported dental radiology..

3.
Dentomaxillofac Radiol ; 52(7): 20230141, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37641960

RESUMO

OBJECTIVES: This study aims to evaluate the reliability of AI-generated STL files in diagnosing osseous changes of the mandibular condyle and compare them to a ground truth (GT) diagnosis made by six radiologists. METHODS: A total of 432 retrospective CBCT images from four universities were evaluated by six dentomaxillofacial radiologists who identified osseous changes such as flattening, erosion, osteophyte formation, bifid condyle formation, and osteosclerosis. All images were evaluated by each radiologist blindly and recorded on a spreadsheet. All evaluations were compared and for the disagreements, a consensus meeting was held online to create a uniform GT diagnosis spreadsheet. A web-based dental AI software was used to generate STL files of the CBCT images, which were then evaluated by two dentomaxillofacial radiologists. The new observer, GT, was compared to this new STL file evaluation, and the interclass correlation (ICC) value was calculated for each pathology. RESULTS: Out of the 864 condyles assessed, the ground truth diagnosis identified 372 cases of flattening, 185 cases of erosion, 70 cases of osteophyte formation, 117 cases of osteosclerosis, and 15 cases of bifid condyle formation. The ICC values for flattening, erosion, osteophyte formation, osteosclerosis, and bifid condyle formation were 1.000, 0.782, 1.000, 0.000, and 1.000, respectively, when comparing diagnoses made using STL files with the ground truth. CONCLUSIONS: AI-generated STL files are reliable in diagnosing bifid condyle formation, osteophyte formation, and flattening of the condyle. However, the diagnosis of osteosclerosis using AI-generated STL files is not reliable, and the accuracy of diagnosis is affected by the erosion grade.


Assuntos
Osteófito , Osteosclerose , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Côndilo Mandibular/diagnóstico por imagem , Osteófito/diagnóstico por imagem , Osteófito/patologia , Estudos Retrospectivos , Reprodutibilidade dos Testes , Tomografia Computadorizada de Feixe Cônico/métodos , Osteosclerose/diagnóstico por imagem , Articulação Temporomandibular
4.
Diagnostics (Basel) ; 13(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37998607

RESUMO

This study aims to investigate the effect of using an artificial intelligence (AI) system (Diagnocat, Inc., San Francisco, CA, USA) for caries detection by comparing cone-beam computed tomography (CBCT) evaluation results with and without the software. 500 CBCT volumes are scored by three dentomaxillofacial radiologists for the presence of caries separately on a five-point confidence scale without and with the aid of the AI system. After visual evaluation, the deep convolutional neural network (CNN) model generated a radiological report and observers scored again using AI interface. The ground truth was determined by a hybrid approach. Intra- and inter-observer agreements are evaluated with sensitivity, specificity, accuracy, and kappa statistics. A total of 6008 surfaces are determined as 'presence of caries' and 13,928 surfaces are determined as 'absence of caries' for ground truth. The area under the ROC curve of observer 1, 2, and 3 are found to be 0.855/0.920, 0.863/0.917, and 0.747/0.903, respectively (unaided/aided). Fleiss Kappa coefficients are changed from 0.325 to 0.468, and the best accuracy (0.939) is achieved with the aided results. The radiographic evaluations performed with aid of the AI system are found to be more compatible and accurate than unaided evaluations in the detection of dental caries with CBCT images.

5.
Imaging Sci Dent ; 53(3): 199-208, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37799743

RESUMO

Purpose: The objective of this study was to evaluate the accuracy and effectiveness of an artificial intelligence (AI) program in identifying dental conditions using panoramic radiographs (PRs), as well as to assess the appropriateness of its treatment recommendations. Material and Methods: PRs from 100 patients (representing 4497 teeth) with known clinical examination findings were randomly selected from a university database. Three dentomaxillofacial radiologists and the Diagnocat AI software evaluated these PRs. The evaluations were focused on various dental conditions and treatments, including canal filling, caries, cast post and core, dental calculus, fillings, furcation lesions, implants, lack of interproximal tooth contact, open margins, overhangs, periapical lesions, periodontal bone loss, short fillings, voids in root fillings, overfillings, pontics, root fragments, impacted teeth, artificial crowns, missing teeth, and healthy teeth. Results: The AI demonstrated almost perfect agreement (exceeding 0.81) in most of the assessments when compared to the ground truth. The sensitivity was very high (above 0.8) for the evaluation of healthy teeth, artificial crowns, dental calculus, missing teeth, fillings, lack of interproximal contact, periodontal bone loss, and implants. However, the sensitivity was low for the assessment of caries, periapical lesions, pontic voids in the root canal, and overhangs. Conclusion: Despite the limitations of this study, the synthesized data suggest that AI-based decision support systems can serve as a valuable tool in detecting dental conditions, when used with PR for clinical dental applications.

6.
Sci Rep ; 12(1): 11863, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831451

RESUMO

This study aims to generate and also validate an automatic detection algorithm for pharyngeal airway on CBCT data using an AI software (Diagnocat) which will procure a measurement method. The second aim is to validate the newly developed artificial intelligence system in comparison to commercially available software for 3D CBCT evaluation. A Convolutional Neural Network-based machine learning algorithm was used for the segmentation of the pharyngeal airways in OSA and non-OSA patients. Radiologists used semi-automatic software to manually determine the airway and their measurements were compared with the AI. OSA patients were classified as minimal, mild, moderate, and severe groups, and the mean airway volumes of the groups were compared. The narrowest points of the airway (mm), the field of the airway (mm2), and volume of the airway (cc) of both OSA and non-OSA patients were also compared. There was no statistically significant difference between the manual technique and Diagnocat measurements in all groups (p > 0.05). Inter-class correlation coefficients were 0.954 for manual and automatic segmentation, 0.956 for Diagnocat and automatic segmentation, 0.972 for Diagnocat and manual segmentation. Although there was no statistically significant difference in total airway volume measurements between the manual measurements, automatic measurements, and DC measurements in non-OSA and OSA patients, we evaluated the output images to understand why the mean value for the total airway was higher in DC measurement. It was seen that the DC algorithm also measures the epiglottis volume and the posterior nasal aperture volume due to the low soft-tissue contrast in CBCT images and that leads to higher values in airway volume measurement.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Tomografia Computadorizada de Feixe Cônico Espiral , Algoritmos , Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Faringe/diagnóstico por imagem
7.
Sci Rep ; 11(1): 15006, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294759

RESUMO

In this study, a novel AI system based on deep learning methods was evaluated to determine its real-time performance of CBCT imaging diagnosis of anatomical landmarks, pathologies, clinical effectiveness, and safety when used by dentists in a clinical setting. The system consists of 5 modules: ROI-localization-module (segmentation of teeth and jaws), tooth-localization and numeration-module, periodontitis-module, caries-localization-module, and periapical-lesion-localization-module. These modules use CNN based on state-of-the-art architectures. In total, 1346 CBCT scans were used to train the modules. After annotation and model development, the AI system was tested for diagnostic capabilities of the Diagnocat AI system. 24 dentists participated in the clinical evaluation of the system. 30 CBCT scans were examined by two groups of dentists, where one group was aided by Diagnocat and the other was unaided. The results for the overall sensitivity and specificity for aided and unaided groups were calculated as an aggregate of all conditions. The sensitivity values for aided and unaided groups were 0.8537 and 0.7672 while specificity was 0.9672 and 0.9616 respectively. There was a statistically significant difference between the groups (p = 0.032). This study showed that the proposed AI system significantly improved the diagnostic capabilities of dentists.


Assuntos
Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico , Doenças Estomatognáticas/diagnóstico , Tomografia Computadorizada de Feixe Cônico/métodos , Tomografia Computadorizada de Feixe Cônico/normas , Gerenciamento Clínico , Humanos , Processamento de Imagem Assistida por Computador , Variações Dependentes do Observador , Sensibilidade e Especificidade
9.
Clin Biomech (Bristol, Avon) ; 26(1): 90-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20950904

RESUMO

OBJECTIVES: despite the predilection of gout to the feet, the impact of gout on foot function and biomechanics is currently unknown. The aim of this study was to describe the effects of chronic gout upon function and selected biomechanical parameters associated with gait. METHODS: twenty-five patients with a history of gout were compared with 25 age and gender matched control participants with no history of gout or other forms of arthritis. General function, foot specific disease activity and lower limb activities were determined using the Health Assessment Questionnaire, Foot Function Index (pain domain), and Leeds Foot Impact Scale respectively. Each patient also underwent a gait assessment that included plantar pressure measurements and an evaluation of temporal-spatial gait parameters. FINDINGS: patients with chronic gout had higher levels of general and foot-specific disability, pain and impairment (P ≤0.001). Significantly lower peak plantar pressures were observed in the hallux of patients with chronic gout (P ≤0.05). Significantly higher pressure-time integrals were observed in the cases at the midfoot (P ≤0.05), but lower values were observed at the hallux (P ≤0.05). Patients with chronic gout walked slower, with longer step and stride lengths compared to the controls. INTERPRETATION: patients with chronic gout experience pain and disability associated with their feet. Different toe-off strategies may account for functional changes and pain associated with foot problems in chronic gout.


Assuntos
Doenças do Pé/complicações , Doenças do Pé/fisiopatologia , Gota/complicações , Gota/fisiopatologia , Adulto , Fenômenos Biomecânicos , Estudos de Casos e Controles , Doença Crônica , Feminino , Hallux/fisiopatologia , Humanos , Masculino , Dor , Inquéritos e Questionários , Fatores de Tempo , Caminhada
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