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1.
J Oral Maxillofac Surg ; 72(3): 449-55, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24215659

RESUMO

PURPOSE: This study was designed to evaluate clinical photographs published in the Journal of Oral and Maxillofacial Surgery (JOMS) and understand the current status of oral and maxillofacial surgery. MATERIALS AND METHODS: A total of 1,317 photographs from the JOMS Volume 69 were assessed. These photographs were scored from 1 to 10 for the following parameters: sharpness; depth of field; exposure; composition; color or grayscale; background; position; distortion; label consistency; and white balance. Then, the distributions of scores were analyzed. Each score was compared with the average score. The effects of different subjects; emergency or nonemergency situations; and intraoperative, preoperative, or postoperative conditions on the quality of photographs were analyzed by conducting a nonparametric Kruskal-Wallis test. RESULTS: The total score of each photograph showed a left-skewed distribution, varying from 3 to 10, with an average score of 6.82. Four parameters, including sharpness, depth of field, exposure, and white balance, scored less than the average score. Photographs with an intraoral subject yielded the lowest score, with a significant difference (P < .05). The score of photographs taken during a nonemergency situation was significantly higher than that during an emergency situation (6.84 vs 6.03; P < .001). Photographs of an intraoperative condition yielded a score significantly lower than those of pre- and postoperative conditions (6.53 vs 7.11 and 6.75, respectively; P < .001). Approximately 45.5% of photographs (148 of 325) displayed uncovered eyes and 57.1% of specimens (40 of 70) did not appear with a plotting scale. CONCLUSIONS: Sharpness, depth of field, exposure, and white balance should be considered to a greater extent than the other parameters when oral and maxillofacial photographs are taken, particularly for intraoral conditions, emergency situations, and intraoperative conditions. Enhanced parameters and protection of a patient's identity may significantly improve the average level of photographic quality.


Assuntos
Publicações Periódicas como Assunto , Fotografia Dentária/normas , Cirurgia Bucal , Humanos , Variações Dependentes do Observador , Estatísticas não Paramétricas
2.
Sci Total Environ ; 882: 163466, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37088385

RESUMO

Microplastics (MPs), as emerging contaminants can behave as carriers for heavy metals in the water environments. Although the adsorption performance of heavy metals on MPs has been widely investigated, the effects of humic acids (HA) on the adsorption have seldom been explored. The authors were compared the Pb(II) adsorption onto biofilm-developed polyvinyl chloride (Bio-PVC) MPs with Pb(II) adsorption onto virgin PVC MPs (V-PVC), and explored the relationship between surface characteristics and the adsorption properties in the coexistence of HA. Our results showed that due to a larger specific surface area and more oxygen containing groups, Bio-PVC had a larger adsorption capability with a value of 3.57 mg/g than original ones (1.85 mg/g) due to its huge specific surface area and more oxygen containing groups. Microbial community analysis showed that the predominate bacteria in biofilms as Proteobacteria, Acidobacteria, Cyanobacteria, Firmicutes, and Bacteroidetes. Notably, the Pb(II) adsorption onto the V-PVC surfaces was increased, but the adsorption capacities of Pb(II) on Bio-PVC were suppressed with increasing HA. With the co-existence of HA, the increasing complexation and electrostatic attraction had attributed to the increased Pb(II) adsorption ability on V-PVC. Except for its competitive ability, HA has a shield effect which decreases the sorption sites on Bio-PVC. Overall, our findings provide a better understanding of the HA effect on the adsorption mechanism of heavy metals onto MPs in aquatic ecosystems.


Assuntos
Metais Pesados , Microbiota , Poluentes Químicos da Água , Microplásticos , Plásticos , Substâncias Húmicas , Chumbo , Adsorção , Poluentes Químicos da Água/análise , Água , Íons , Biofilmes
3.
EClinicalMedicine ; 27: 100558, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33150326

RESUMO

BACKGROUND: The overall prognosis of oral cancer remains poor because over half of patients are diagnosed at advanced-stages. Previously reported screening and earlier detection methods for oral cancer still largely rely on health workers' clinical experience and as yet there is no established method. We aimed to develop a rapid, non-invasive, cost-effective, and easy-to-use deep learning approach for identifying oral cavity squamous cell carcinoma (OCSCC) patients using photographic images. METHODS: We developed an automated deep learning algorithm using cascaded convolutional neural networks to detect OCSCC from photographic images. We included all biopsy-proven OCSCC photographs and normal controls of 44,409 clinical images collected from 11 hospitals around China between April 12, 2006, and Nov 25, 2019. We trained the algorithm on a randomly selected part of this dataset (development dataset) and used the rest for testing (internal validation dataset). Additionally, we curated an external validation dataset comprising clinical photographs from six representative journals in the field of dentistry and oral surgery. We also compared the performance of the algorithm with that of seven oral cancer specialists on a clinical validation dataset. We used the pathological reports as gold standard for OCSCC identification. We evaluated the algorithm performance on the internal, external, and clinical validation datasets by calculating the area under the receiver operating characteristic curves (AUCs), accuracy, sensitivity, and specificity with two-sided 95% CIs. FINDINGS: 1469 intraoral photographic images were used to validate our approach. The deep learning algorithm achieved an AUC of 0·983 (95% CI 0·973-0·991), sensitivity of 94·9% (0·915-0·978), and specificity of 88·7% (0·845-0·926) on the internal validation dataset (n = 401), and an AUC of 0·935 (0·910-0·957), sensitivity of 89·6% (0·847-0·942) and specificity of 80·6% (0·757-0·853) on the external validation dataset (n = 402). For a secondary analysis on the internal validation dataset, the algorithm presented an AUC of 0·995 (0·988-0·999), sensitivity of 97·4% (0·932-1·000) and specificity of 93·5% (0·882-0·979) in detecting early-stage OCSCC. On the clinical validation dataset (n = 666), our algorithm achieved comparable performance to that of the average oral cancer expert in terms of accuracy (92·3% [0·902-0·943] vs 92.4% [0·912-0·936]), sensitivity (91·0% [0·879-0·941] vs 91·7% [0·898-0·934]), and specificity (93·5% [0·909-0·960] vs 93·1% [0·914-0·948]). The algorithm also achieved significantly better performance than that of the average medical student (accuracy of 87·0% [0·855-0·885], sensitivity of 83·1% [0·807-0·854], and specificity of 90·7% [0·889-0·924]) and the average non-medical student (accuracy of 77·2% [0·757-0·787], sensitivity of 76·6% [0·743-0·788], and specificity of 77·9% [0·759-0·797]). INTERPRETATION: Automated detection of OCSCC by deep-learning-powered algorithm is a rapid, non-invasive, low-cost, and convenient method, which yielded comparable performance to that of human specialists and has the potential to be used as a clinical tool for fast screening, earlier detection, and therapeutic efficacy assessment of the cancer.

4.
Biomed Res Int ; 2019: 7267062, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31008111

RESUMO

PURPOSE: To date, it remains unknown whether the addition of platelet-rich fibrin (PRF) to bone grafts actually improves the effectiveness of maxillary sinus augmentation. This study aimed to perform a meta-analysis to evaluate the efficacy of PRF in sinus lift. MATERIALS AND METHODS: PubMed, Embase, and the Cochrane Library were searched. Randomized controlled studies were identified. The risk of bias was evaluated using the Cochrane Collaboration tool. RESULTS: Five RCTs were included in our meta-analysis. Clinical, radiographic, and histomorphometric outcomes were considered. No implant failure or graft failure was detected in all included studies within the follow-up period. The percentage of contact length between newly formed bone substitute and bone in the PRF group was lower but lacked statistical significance (3.90%, 95% CI, -2.91% to 10.71%). The percentages of new bone formation (-1.59%, 95% CI, -5.36% to 2.18%) and soft-tissue area (-3.73%, 95% CI, -10.11% to 2.66%) were higher in the PRF group but were not significantly different. The percentage of residual bone graft was not significant in either group (4.57%, 95% CI, 0% to 9.14%). CONCLUSIONS: Within the limitations of this review, it was concluded that there were no statistical differences in survival rate, new bone formation, contact between newly formed bone and bone substitute, percentage of residual bone graft (BSV/TV), and soft-tissue area between the non-PRF and PRF groups. Current evidence supporting the necessity of adding PRF to bone graft in sinus augmentation is limited.


Assuntos
Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Fibrina Rica em Plaquetas , Levantamento do Assoalho do Seio Maxilar , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Humanos , Seio Maxilar/efeitos dos fármacos , Seio Maxilar/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Comput Methods Biomech Biomed Engin ; 19(3): 240-247, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25693635

RESUMO

Few studies are performed to evaluate the influence of connection type on the stress distribution of distal extension mandibular removable partial dentures (RPDs) supported by both implants and natural teeth. In this study, five three-dimensional finite element models were prepared to simulate mandibular bilateral partially edentulous arches. Four were RPDs supported by both implants and natural teeth, and the other one was RPDs supported only by natural teeth. The maximum equivalent (EQV) stress values of bone around implants, the abutments, and the mucosa displacements of the related supporting structures were measured. It was found that a non-rigid telescopic coping was more favorable to protect the implant than a rigid telescopic coping. Compared with other connection types, the easy resilient attachment (ERA) system seemed to be effective to associate implant without complications. However, the results obtained in the present study should be cautiously interpreted in the clinic.


Assuntos
Prótese Dentária Fixada por Implante , Prótese Parcial Removível , Mandíbula , Estresse Mecânico , Dente , Adulto , Osso e Ossos , Dente Suporte , Análise de Elementos Finitos , Humanos , Masculino , Modelos Biológicos , Periodonto
6.
Biomaterials ; 31(13): 3479-91, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20138663

RESUMO

Current strategies to limit macrophage adhesion, fusion and fibrous capsule formation in the foreign body response have focused on modulating material surface properties. We hypothesize that topography close to biological scale, in the micron and nanometric range, provides a passive approach without bioactive agents to modulate macrophage behavior. In our study, topography-induced changes in macrophage behavior was examined using parallel gratings (250 nm-2 mum line width) imprinted on poly(epsilon-caprolactone) (PCL), poly(lactic acid) (PLA) and poly(dimethyl siloxane) (PDMS). RAW 264.7 cell adhesion and elongation occurred maximally on 500 nm gratings compared to planar controls over 48 h. TNF-alpha and VEGF secretion levels by RAW 264.7 cells showed greatest sensitivity to topographical effects, with reduced levels observed on larger grating sizes at 48 h. In vivo studies at 21 days showed reduced macrophage adhesion density and degree of high cell fusion on 2 mum gratings compared to planar controls. It was concluded that topography affects macrophage behavior in the foreign body response on all polymer surfaces examined. Topography-induced changes, independent of surface chemistry, did not reveal distinctive patterns but do affect cell morphology and cytokine secretion in vitro, and cell adhesion in vivo particularly on larger size topography compared to planar controls.


Assuntos
Reação a Corpo Estranho/imunologia , Macrófagos/imunologia , Modelos Biológicos , Polímeros , Animais , Linhagem Celular , Camundongos , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
J Control Release ; 139(1): 48-55, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19539680

RESUMO

Although viral gene transfer is efficient in achieving transgene expression for tissue engineering, drawbacks of virus dissemination, toxicity and transient gene expression due to immune response have hindered its widespread application. Many tissue engineering studies thus opt to genetically engineer cells in vitro prior to their introduction in vivo. However, it would be attractive to obviate the need for in vitro manipulation by transducing the infiltrating progenitor cells in situ. This study introduces the fabrication of a virus-encapsulated electrospun fibrous scaffold to achieve sustained and localized transduction. Adenovirus encoding the gene for green fluorescent protein was efficiently encapsulated into the core of poly(epsilon-caprolactone) fibers through co-axial electrospinning and was subsequently released via a porogen-mediated process. HEK 293 cells seeded on the scaffolds expressed high level of transgene expression over a month, while cells inoculated by scaffold supernatant showed only transient expression for a week. RAW 264.7 cells cultured on the virus-encapsulated fibers produced a lower level of IL-1 beta, TNF-alpha and IFN-alpha, suggesting that the activation of macrophage cells by the viral vector was reduced when encapsulated in the core-shell PCL fibers. In demonstrating sustained and localized cell transduction, this study presents an attractive alternative mode of applying viral gene transfer for regenerative medicine.


Assuntos
Técnicas de Transferência de Genes/instrumentação , Nanotubos , Adenoviridae/genética , Citomegalovirus/genética , Preparações de Ação Retardada , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Humanos , Cinética , Macrófagos/metabolismo , Macrófagos/virologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Poliésteres , Regiões Promotoras Genéticas/genética , Transgenes/genética , Replicação Viral
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