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1.
BMC Oral Health ; 24(1): 804, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014389

RESUMO

BACKGROUND: Tooth segmentation on intraoral scanned (IOS) data is a prerequisite for clinical applications in digital workflows. Current state-of-the-art methods lack the robustness to handle variability in dental conditions. This study aims to propose and evaluate the performance of a convolutional neural network (CNN) model for automatic tooth segmentation on IOS images. METHODS: A dataset of 761 IOS images (380 upper jaws, 381 lower jaws) was acquired using an intraoral scanner. The inclusion criteria included a full set of permanent teeth, teeth with orthodontic brackets, and partially edentulous dentition. A multi-step 3D U-Net pipeline was designed for automated tooth segmentation on IOS images. The model's performance was assessed in terms of time and accuracy. Additionally, the model was deployed on an online cloud-based platform, where a separate subsample of 18 IOS images was used to test the clinical applicability of the model by comparing three modes of segmentation: automated artificial intelligence-driven (A-AI), refined (R-AI), and semi-automatic (SA) segmentation. RESULTS: The average time for automated segmentation was 31.7 ± 8.1 s per jaw. The CNN model achieved an Intersection over Union (IoU) score of 91%, with the full set of teeth achieving the highest performance and the partially edentulous group scoring the lowest. In terms of clinical applicability, SA took an average of 860.4 s per case, whereas R-AI showed a 2.6-fold decrease in time (328.5 s). Furthermore, R-AI offered higher performance and reliability compared to SA, regardless of the dentition group. CONCLUSIONS: The 3D U-Net pipeline was accurate, efficient, and consistent for automatic tooth segmentation on IOS images. The online cloud-based platform could serve as a viable alternative for IOS segmentation.


Assuntos
Redes Neurais de Computação , Dente , Humanos , Dente/diagnóstico por imagem , Dente/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
2.
J Pharmacokinet Pharmacodyn ; 50(3): 229-241, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877385

RESUMO

Monoclonal antibodies, endogenous IgG, and serum albumin bind to FcRn in the endosome for salvaging and recycling after pinocytotic uptake, which prolongs their half-life. This mechanism has been broadly recognized and is incorporated in currently available PBPK models. Newer types of large molecules have been designed and developed, which also bind to FcRn in the plasma space for various mechanistic reasons. To incorporate FcRn binding affinity in PBPK models, binding in the plasma space and subsequent internalisation into the endosome needs to be explicitly represented. This study investigates the large molecules model in PK-Sim® and its applicability to molecules with FcRn binding affinity in plasma. With this purpose, simulations of biologicals with and without plasma binding to FcRn were performed with the large molecule model in PK-Sim®. Subsequently, this model was extended to ensure a more mechanistic description of the internalisation of FcRn and the FcRn-drug complexes. Finally, the newly developed model was used in simulations to explore the sensitivity for FcRn binding in the plasma space, and it was fitted to an in vivo dataset of wild-type IgG and FcRn inhibitor plasma concentrations in Tg32 mice. The extended model demonstrated a strongly increased sensitivity of the terminal half-life towards the plasma FcRn binding affinity and could successfully fit the in vivo dataset in Tg32 mice with meaningful parameter estimates.


Assuntos
Anticorpos Monoclonais , Receptores Fc , Camundongos , Animais , Receptores Fc/metabolismo , Anticorpos Monoclonais/metabolismo , Endossomos/metabolismo , Imunoglobulina G/metabolismo
3.
J Emerg Med ; 50(4): e191-3, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26899519

RESUMO

BACKGROUND: Lemierre syndrome is an uncommon, potentially lethal disorder combining acute oropharyngeal infection caused by Fusobacterium necrophorum, with jugular vein suppurative thrombosis, complicated by anaerobic sepsis with secondary multiple metastatic abscesses. Optimal treatment outcome with reduced or absence of sequelae can be achieved with early diagnosis. CASE REPORT: We present a clinical case of Fusobacterium necrophorum abscess complicated with femoral vein thrombosis, called atypical localization of Lemierre syndrome. This uncommon disease was diagnosed on the basis of clinical, biological, and imaging tests, with a favorable outcome, after a well-orientated antibiotic and surgical course of therapy. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Since its first description in 1936, Lemierre syndrome has been reported in locations other than its initial oropharyngeal site. Because optimal treatment outcome is dependent on early diagnosis, it is imperative for emergency physicians to be aware of this uncommon disease, because in many instances they are the patient's initial point of contact with medical care.


Assuntos
Síndrome de Lemierre/diagnóstico , Meios de Contraste , Diagnóstico Diferencial , Diagnóstico por Imagem , Serviço Hospitalar de Emergência , Humanos , Masculino , Pessoa de Meia-Idade
4.
Sci Rep ; 13(1): 21049, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030618

RESUMO

The aim of this study was to assess the morphological characteristics of the coronoid process (CP) and define coronoid hyperplasia (CH) using cadaveric mandibles of a Caucasian population. A sample of 151 adult dry cadaveric mandibles (302 CPs) was acquired. Three distances were measured, which included the width, height, and length of CP. The surface area measurements involved area A: above the width distance line; area B: between incisura mandibulae-Alveolar ridge line and width distance line; area C: between distance lines of width and height. Finally, angulations of the CP and gonial angles were identified. Both length and surface area A + B acted as hyperplastic indicators. Based on the selection criteria, a sample of 197 CPs was included. The hooked shape (59%) was most commonly observed. No significant difference existed between left and right sides (p > 0.05). The mean values of length and surface area A + B were 2.2 ± 0.3 cm and 3.3 ± 0.8 cm2, and any values above 2.7 cm (n = 5 CPs- 2.5%) and 5.0 cm2 (n = 9 CPs- 4.6%) were described as hyperplastic, respectively. The presented data could act as quantitative reference for differentiating between normal and hyperplastic conditions.


Assuntos
Articulação do Cotovelo , Ulna , Adulto , Humanos , Hiperplasia/patologia , Ulna/anatomia & histologia , Mandíbula/anatomia & histologia , Articulação do Cotovelo/anatomia & histologia , Cadáver
5.
J Biol Chem ; 286(30): 26555-67, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21646349

RESUMO

As glucocorticoid resistance (GCR) and the concomitant burden pose a worldwide problem, there is an urgent need for a more effective glucocorticoid therapy, for which insights into the molecular mechanisms of GCR are essential. In this study, we addressed the hypothesis that TNFα, a strong pro-inflammatory mediator in numerous inflammatory diseases, compromises the protective function of the glucocorticoid receptor (GR) against TNFα-induced lethal inflammation. Indeed, protection of mice by dexamethasone against TNFα lethality was completely abolished when it was administered after TNFα stimulation, indicating compromised GR function upon TNFα challenge. TNFα-induced GCR was further demonstrated by impaired GR-dependent gene expression in the liver. Furthermore, TNFα down-regulates the levels of both GR mRNA and protein. However, this down-regulation seems to occur independently of GC production, as TNFα also resulted in down-regulation of GR levels in adrenalectomized mice. These findings suggest that the decreased amount of GR determines the GR response and outcome of TNFα-induced shock, as supported by our studies with GR heterozygous mice. We propose that by inducing GCR, TNFα inhibits a major brake on inflammation and thereby amplifies the pro-inflammatory response. Our findings might prove helpful in understanding GCR in inflammatory diseases in which TNFα is intimately involved.


Assuntos
Regulação para Baixo , Receptores de Glucocorticoides/biossíntese , Choque/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Feminino , Camundongos , Camundongos Transgênicos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Glucocorticoides/genética , Choque/induzido quimicamente , Choque/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/toxicidade
6.
Cancer Res ; 67(15): 7301-7, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17671199

RESUMO

Tumor necrosis factor (TNF)-induced inflammation prevents its broad application as an antitumor agent. We here report that addition of ZnSO(4) to the drinking water of mice induces expression of heat shock protein 70 (HSP70) in several organs, notably the gastrointestinal track. Zinc conferred dose-responsive protection against TNF-induced hypothermia, systemic induction of interleukin-6 and NO(x), as well as against TNF-induced bowel cell death and death of the organism. The protective effect of zinc was completely absent in mice deficient in the major HSP70-inducible gene, hsp70.1, whereas transgenic mice constitutively expressing the human HSP70.A gene, under control of a beta-actin promoter, was also protected against TNF, indicating that an increase in HSP70 is necessary and sufficient to confer protection. The therapeutic potential of the protection induced by ZnSO(4) was clearly shown in a TNF/IFNgamma-based antitumor therapy using three different tumor models. In hsp70.1 wild-type mice, but not in hsp70.1-deficient mice, zinc very significantly protected against lethality but left the antitumor effect intact. We conclude that zinc protects against TNF in a HSP70-dependent way and that protection by zinc could be helpful in developing a safer anticancer therapy with TNF/IFNgamma.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Choque Térmico HSP70/metabolismo , Inflamação/prevenção & controle , Fator de Necrose Tumoral alfa/toxicidade , Sulfato de Zinco/uso terapêutico , Animais , Antivirais/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Proteínas de Choque Térmico HSP70/genética , Humanos , Hipotermia , Inflamação/metabolismo , Inflamação/patologia , Interferon gama/uso terapêutico , Interleucina-6/metabolismo , Intestino Delgado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Necrose , Neoplasias Experimentais/tratamento farmacológico , Taxa de Sobrevida , Células Tumorais Cultivadas
8.
Animals (Basel) ; 6(1)2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26703742

RESUMO

As of 2012, the EU has banned the use of conventional cages (CC) for laying hens, causing a shift in housing systems. This study's aim was to gain insight into farmers' opinions on hen health and welfare in their current housing systems. A survey was sent to 218 Belgian egg farmers, of which 127 (58.3%) responded, with 84 still active as egg farmer. Hen welfare tended to be less important in choosing the housing system for farmers with cage than with non-cage systems. Respondents currently using cage systems were more satisfied with hen health than respondents with non-cage systems. Reported mortality increased with farm size and was higher in furnished cages than in floor housing. Feather pecking, cannibalism, smothering and mortality were perceived to be higher in current housing systems than in CC, but only by respondents who shifted to non-cage systems from previously having had CC. Health- and production-related parameters were scored to be more important for hen welfare as compared to behavior-related parameters. Those without CC in the past rated factors relating to natural behavior to be more important for welfare than those with CC. This difference in opinion based on farmer backgrounds should be taken into account in future research.

9.
J Clin Invest ; 122(6): 2130-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22585571

RESUMO

Glucocorticoids acting through the glucocorticoid receptor (GR) inhibit TNF-induced lethal inflammation. Here, we demonstrate that GR dimerization plays a role in reducing TNF sensitivity. In mutant mice unable to dimerize GR, we found that TNF failed to induce MAPK phosphatase 1 (MKP1). We assessed TNF sensitivity in Mkp1(-/-) mice and found increased inflammatory gene induction in livers, increased circulating cytokines, cell death in intestinal epithelium, severe intestinal inflammation, hypothermia, and death. Mkp1(-/-) mice had increased levels of phosphorylated JNK, which promotes apoptosis, in liver tissue. We further examined JNK-deficient mice for their response to TNF. Although Jnk1(-/-) mice showed no change in sensitivity to TNF, Jnk2(-/-) mice were significantly protected against TNF, identifying JNK2 as an essential player in inflammation induced by TNF. Furthermore, we found that loss of Jnk2 partially rescued the increased sensitivity of Mkp1(-/-) and mutant GR mice to TNF. Our data show that GR dimerization inhibits JNK2 through MKP1 and protects from TNF-induced apoptosis and lethal inflammation.


Assuntos
Apoptose/efeitos dos fármacos , Fosfatase 1 de Especificidade Dupla , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Receptores de Glucocorticoides/metabolismo , Fator de Necrose Tumoral alfa/efeitos adversos , Animais , Apoptose/genética , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/genética , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Mucosa Intestinal/patologia , Fígado/patologia , MAP Quinase Quinase 7/genética , MAP Quinase Quinase 7/metabolismo , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Multimerização Proteica , Receptores de Glucocorticoides/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
10.
Cytokine Growth Factor Rev ; 21(4): 275-86, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20456998

RESUMO

TNF is a Janus-faced protein. It possesses impressive anti-tumor activities, but it is also one of the strongest known pro-inflammatory cytokines, which hampers its use as a systemic anti-cancer agent. TNF has been shown to play a detrimental role in inflammatory diseases such as rheumatoid arthritis and inflammatory bowel disease. Glucocorticoids are strongly anti-inflammatory and exert their therapeutic effects through binding to their receptor, the glucocorticoid receptor. Therefore, glucocorticoids have been used for over half a century for the treatment of inflammatory diseases. However, many patients are or become resistant to the therapeutic effects of glucocorticoids. Inflammatory cytokines have been suggested to play an important role in this steroid insensitivity or glucocorticoid resistance. This review aims to highlight the mechanisms of mutual inhibition between TNF and GR signaling pathways.


Assuntos
Receptor Cross-Talk , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/fisiologia
11.
Plant Physiol ; 137(2): 588-601, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15710687

RESUMO

Transcript profiling is crucial to study biological systems, and various platforms have been implemented to survey mRNAs at the genome scale. We have assessed the performance of the CATMA microarray designed for Arabidopsis (Arabidopsis thaliana) transcriptome analysis and compared it with the Agilent and Affymetrix commercial platforms. The CATMA array consists of gene-specific sequence tags of 150 to 500 bp, the Agilent (Arabidopsis 2) array of 60mer oligonucleotides, and the Affymetrix gene chip (ATH1) of 25mer oligonucleotide sets. We have matched each probe repertoire with the Arabidopsis genome annotation (The Institute for Genomic Research release 5.0) and determined the correspondence between them. Array performance was analyzed by hybridization with labeled targets derived from eight RNA samples made of shoot total RNA spiked with a calibrated series of 14 control transcripts. CATMA arrays showed the largest dynamic range extending over three to four logs. Agilent and Affymetrix arrays displayed a narrower range, presumably because signal saturation occurred for transcripts at concentrations beyond 1,000 copies per cell. Sensitivity was comparable for all three platforms. For Affymetrix GeneChip data, the RMA software package outperformed Microarray Suite 5.0 for all investigated criteria, confirming that the information provided by the mismatch oligonucleotides has no added value. In addition, taking advantage of replicates in our dataset, we conducted a robust statistical analysis of the platform propensity to yield false positive and false negative differentially expressed genes, and all gave satisfactory results. The results establish the CATMA array as a mature alternative to the Affymetrix and Agilent platforms.


Assuntos
Arabidopsis/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA de Plantas/genética , Reações Falso-Negativas , Reações Falso-Positivas , Expressão Gênica , RNA Mensageiro , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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