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1.
J Am Chem Soc ; 146(17): 12174-12184, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629886

RESUMO

Orthocarboxylic acids─organic molecules carrying three hydroxyl groups at the same carbon atom─have been distinguished as vital reactive intermediates by the atmospheric science and physical (organic) chemistry communities as transients in the atmospheric aerosol cycle. Predicted short lifetimes and their tendency to dehydrate to a carboxylic acid, free orthocarboxylic acids, signify one of the most elusive classes of organic reactive intermediates, with even the simplest representative methanetriol (CH(OH)3)─historically known as orthoformic acid─not previously been detected experimentally. Here, we report the first synthesis of the previously elusive methanetriol molecule in low-temperature mixed methanol (CH3OH) and molecular oxygen (O2) ices subjected to energetic irradiation. Supported by electronic structure calculations, methanetriol was identified in the gas phase upon sublimation via isomer-selective photoionization reflectron time-of-flight mass spectrometry combined with isotopic substitution studies and the detection of photoionization fragments. The first synthesis and detection of methanetriol (CH(OH)3) reveals its gas-phase stability as supported by a significant barrier hindering unimolecular decomposition. These findings progress our fundamental understanding of the chemistry and chemical bonding of methanetriol, hydroxyperoxymethane (CH3OOOH), and hydroxyperoxymethanol (CH2(OH)OOH), which are all prototype molecules in the oxidation chemistry of the atmosphere.

2.
Chem Res Toxicol ; 37(2): 311-322, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38238692

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP) is a sort of endocrine disruptor that induces abnormal physiological and biochemical activities such as epigenetic alterations, apoptosis, and oxidative stress. MicroRNAs (miRNAs) are a class of short noncoding RNAs that may regulate the expression of many protein-coding genes when organisms are exposed to environmental chemicals. miR-222b is a differentially expressed miRNA after DEHP exposure. miRNA-mRNA prediction suggested that BTB (POZ) structural domain 6b (BTBD6B) might be a target mRNA of miR-222b, and DEHP exposure altered its expression. However, the correlation between miR-222b and BTBD6B has not been experimentally confirmed. The aim of this study was to investigate the regulation of BTBD6B by miR-222b in zebrafish embryos under the effect of low concentration of DEHP. Dual fluorescent protein assays and dual luciferase reporter gene assays confirmed the interaction between miR-222b and the 3'-untranslated region (3'-UTR) of BTBD6B. Ectopic expression assays showed that miR-222b could negatively regulate BTBD6B in ZF4 cells. However, the relative expression of miR-222b and BTBD6B was significantly higher at both transcriptional and post-transcriptional levels in zebrafish embryos exposed to low concentrations of DEHP. The results of this study improved our understanding of the molecular mechanism of DEHP exposure toxicity. It identified that the aberrant expression of miR-222b/BTBD6B may be one of the mechanisms of DEHP toxicity, which can provide a theoretical reference and scientific basis for environmental management and biological health risk assessment.


Assuntos
Dietilexilftalato , MicroRNAs , Animais , Peixe-Zebra/genética , Dietilexilftalato/toxicidade , MicroRNAs/genética , Estresse Oxidativo , RNA Mensageiro
3.
Molecules ; 29(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38675602

RESUMO

Alzheimer's disease (AD) is a complex neurodegenerative disease that can lead to the loss of cognitive function. The progression of AD is regulated by multiple signaling pathways and their associated targets. Therefore, multitarget strategies theoretically have greater potential for treating AD. In this work, a series of new hybrids were designed and synthesized by the hybridization of tacrine (4, AChE: IC50 = 0.223 µM) with pyrimidone compound 5 (GSK-3ß: IC50 = 3 µM) using the cysteamine or cystamine group as the connector. The biological evaluation results demonstrated that most of the compounds exhibited moderate to good inhibitory activities against acetylcholinesterase (AChE) and glycogen synthase kinase 3ß (GSK-3ß). The optimal compound 18a possessed potent dual AChE/GSK-3ß inhibition (AChE: IC50 = 0.047 ± 0.002 µM, GSK-3ß: IC50 = 0.930 ± 0.080 µM). Further molecular docking and enzymatic kinetic studies revealed that this compound could occupy both the catalytic anionic site and the peripheral anionic site of AChE. The results also showed a lack of toxicity to SH-SY5Y neuroblastoma cells at concentrations of up to 25 µM. Collectively, this work explored the structure-activity relationships of novel tetrahydroacridin hybrids with sulfur-inserted linkers, providing a reference for the further research and development of new multitarget anti-AD drugs.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Inibidores da Colinesterase , Desenho de Fármacos , Glicogênio Sintase Quinase 3 beta , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Humanos , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Acetilcolinesterase/metabolismo , Acetilcolinesterase/química , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Linhagem Celular Tumoral , Enxofre/química , Relação Estrutura-Atividade , Acridinas/química , Acridinas/farmacologia , Acridinas/síntese química , Tacrina/química , Tacrina/farmacologia , Tacrina/síntese química , Estrutura Molecular
4.
Angew Chem Int Ed Engl ; 63(23): e202402756, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38563770

RESUMO

This article presents trioxa[9]circulene (3) as a novel member of hetero[n]circulenes. Its synthesis began with the synthesis of dimethoxydioxa[8]helicene (5) and used dimethoxydiepoxycyclononatrinaphthalene (4) as a key intermediate, despite the condensation reaction predominantly yielding a 1,4-addition byproduct. The structures and properties of 3-5 were extensively investigated using experimental and computational methods. Analysis of the crystal structures reveal elongation of the internal C-C bonds in the nine-membered ring of 3 compared to 4 and 5. Computational studies demonstrate the remarkable flexibility of trioxa[9]circulene's saddle-shaped polycyclic framework, while the other two compounds are rigid with large racemization barriers. Optically pure forms of 4 and 5 exhibit absorption and luminescence dissymmetry factors on the order of 10-2, with smaller values observed for compound 4. In the crystal structures, molecules of 3 stack to form columns with remarkable π-π overlap, and the π-π interactions of 4 exhibit short intermolecular C-to-C contacts. Consequently, the solution-processed film of 4 functioned as a p-type organic semiconductor in field effect transistors.

6.
Mol Nutr Food Res ; 68(6): e2300553, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38366962

RESUMO

SCOPE: Nonalcoholic steatohepatitis (NASH) is an increasingly common chronic liver disease in which hepatic fibrosis is the major pathological change. The transforming growth factor ß (TGF-ß)/mall mothers against decapentaplegic (Smad) signaling is the main effector of fibrosis. Although the antifibrotic effect of echinacoside (Ech) on the liver has been indicated previously, the cellular and molecular mechanisms remain unclear. This study aims to investigate both in vivo and in vitro antifibrotic properties of Ech. METHODS AND RESULTS: Cell viability and scratch/wound assays show that Ech significantly inhibits the proliferation, migration, and activation of human hepatic stellate LX-2 cells. In mice with high-fat diet-induced hepatic fibrosis, Ech treatment attenuates the progression of liver injury, inflammation, and fibrosis. Furthermore, transcriptome analysis and subsequent functional validation demonstrate that Ech achieves antifibrotic effects by the activin receptor type-2A (ACVR2A)-mediated TGF-ß1/Smad signaling pathway; ultimately, ACVR2A is demonstrated to be an important target for hepatic fibrosis by inhibiting and inducing the expression of ACVR2A in LX-2 cells. CONCLUSION: Ech exerts potent antifibrotic effects by inhibiting the ACVR2A-mediated TGF-ß1/Smad signaling axis and may serve as an alternative treatment for hepatic fibrosis.


Assuntos
Glicosídeos , Proteínas Smad , Fator de Crescimento Transformador beta1 , Camundongos , Humanos , Animais , Proteínas Smad/metabolismo , Fibrose , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia
7.
Sci Rep ; 14(1): 7847, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570595

RESUMO

Gastric cancer is a highly prevalent disease that poses a serious threat to public health. In clinical practice, gastroscopy is frequently used by medical practitioners to screen for gastric cancer. However, the symptoms of gastric cancer at different stages of advancement vary significantly, particularly in the case of early gastric cancer (EGC). The manifestations of EGC are often indistinct, leading to a detection rate of less than 10%. In recent years, researchers have focused on leveraging deep learning algorithms to assist medical professionals in detecting EGC and thereby improve detection rates. To enhance the ability of deep learning to detect EGC and segment lesions in gastroscopic images, an Improved Mask R-CNN (IMR-CNN) model was proposed. This model incorporates a "Bi-directional feature extraction and fusion module" and a "Purification module for feature channel and space" based on the Mask R-CNN (MR-CNN). Our study includes a dataset of 1120 images of EGC for training and validation of the models. The experimental results indicate that the IMR-CNN model outperforms the original MR-CNN model, with Precision, Recall, Accuracy, Specificity and F1-Score values of 92.9%, 95.3%, 93.9%, 92.5% and 94.1%, respectively. Therefore, our proposed IMR-CNN model has superior detection and lesion segmentation capabilities and can effectively aid doctors in diagnosing EGC from gastroscopic images.


Assuntos
Aprendizado Profundo , Neoplasias Gástricas , Humanos , Gastroscopia , Neoplasias Gástricas/diagnóstico por imagem , Gastroscópios
8.
Phytomedicine ; 130: 155744, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38763011

RESUMO

BACKGROUND: Aging is associated with learning and memory disorder, affecting multiple brain areas, especially the hippocampus. Previous studies have demonstrated trilobatin (TLB), as a natural food additive, can extend the life of Caenorhabditis elegans and exhibit neuroprotection in Alzheimer's disease mice. However, the possible significance of TLB in anti-aging remains elusive. PURPOSE: This study aimed to delve into the physiological mechanism by which TLB ameliorated aging-induced cognitive impairment in senescence-accelerated mouse prone 8 (SAMP8) mice. METHODS: 6-month-old SAMP8 mice were administrated with TLB (5, 10, 20 mg/kg/day, i.g.) for 3 months. The therapeutic effect of TLB on aging-induced cognitive impairment was assessed in mice using behavioral tests and aging score. The gut microbiota composition in fecal samples was analyzed by metagenomic analysis. The protective effects of TLB on blood-brain barrier (BBB) and intestinal barrier were detected by transmission electron microscope, H&E staining and western blot (WB) assay. The inhibitive effects of TLB on inflammation in brain and intestine were assessed using immunofluorescence, WB and ELISA assay. Molecular docking and surface plasma resonance (SPR) assay were utilized to investigate interaction between TLB and sirtuin 2 (SIRT2). RESULTS: Herein, the findings exhibited TLB mitigated aging-induced cognitive impairment, neuron injury and neuroinflammation in hippocampus of aged SAMP8 mice. Moreover, TLB treatment repaired imbalance of gut microbiota in aged SAMP8 mice. Furthermore, TLB alleviated the damage to BBB and intestinal barrier, concomitant with reducing the expression of SIRT2, phosphorylated levels of c-Jun NH2 terminal kinases (JNK) and c-Jun, and expression of MMP9 protein in aged SAMP8 mice. Molecular docking and SPR unveiled TLB combined with SIRT2 and down-regulated SIRT2 protein expression. Mechanistically, the potential mechanism of SIRT2 in TLB that exerted anti-aging effect was validated in vitro. As expected, SIRT2 deficiency attenuated phosphorylated level of JNK in HT22 cells treated with d-galactose. CONCLUSION: These findings reveal, for the first time, SIRT2-mediated brain-gut barriers contribute to aging and aging-related diseases, and TLB can rescue aging-induced cognitive impairment by targeting SIRT2 and restoring gut microbiota disturbance to mediate the brain-gut axis. Overall, this work extends the potential application of TLB as a natural food additive in aging-related diseases.


Assuntos
Envelhecimento , Eixo Encéfalo-Intestino , Disfunção Cognitiva , Microbioma Gastrointestinal , Sirtuína 2 , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Camundongos , Envelhecimento/efeitos dos fármacos , Sirtuína 2/metabolismo , Masculino , Eixo Encéfalo-Intestino/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Simulação de Acoplamento Molecular , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Modelos Animais de Doenças
9.
Ophthalmol Sci ; 4(3): 100455, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313401

RESUMO

Purpose: To determine the effect of general anesthesia on intraocular pressure (IOP) in children with no intraocular pathology and determine which postanesthetic time point is most predictive of preinduction IOP. Design: Prospective observational study. Participants: Children with no intraocular pathology ≤ 18 years scheduled for general anesthesia as part of their routine care followed by a pediatric ophthalmologist at Nanjing Medical University. Methods: Participants underwent a standardized general anesthetic protocol using a mask induction with sevoflurane and propofol maintenance. Intraocular pressure was measured at the following 7 time points: preinduction (taken in the preoperative area), postinduction minutes 1, 3, and 5, and postairway placement minutes 1, 3, and 5 for a total time period of 10 minutes after induction. A generalized estimating equation was used to evaluate the effect of anesthesia on IOP and the effect of patient factors (age, gender, vital signs, and airway type) on preanesthetic and postanesthetic IOP. An IOP prediction model was developed using the postanesthesia IOP measurements for predicting preinduction IOP. Main Outcome Measures: Intraocular pressure and change in IOP at prespecified time points. Results: Eighty-five children were enrolled with a mean ± standard deviation (SD) age of 7.5 ± 2.9 years. Mean ± SD preinduction IOP was 20.1 ± 3.7 mmHg. Overall, IOP was lowest at 3 minutes postinduction, decreased to a mean of 13.4 ± 3.7 mmHg (P < 0.001). After this, IOP rose 5 minutes postinduction to 16.5 ± 4.2 mmHg, which did not reach preinduction IOP levels (P < 0.001). The IOP prediction model showed that combining 1 minute postinduction and 3 minutes postairway was most predictive (R2 = 0.13), whereas 1 minute postairway was least predictive of preinduction IOP (R2 = 0.01). Conclusions: After the induction of general anesthesia in children, IOP temporarily decreases with a trough at 3 minutes postinduction before increasing and remaining stable just below preinduction levels. Intraocular pressure measurements taken 1 minute after induction with 3 minutes after airway placement are most predictive of preinduction IOP, though predictive value is relatively low. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

10.
Commun Biol ; 7(1): 960, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39117859

RESUMO

Previous studies in small samples have identified inconsistent cortical abnormalities in major depressive disorder (MDD). Despite genetic influences on MDD and the brain, it is unclear how genetic risk for MDD is translated into spatially patterned cortical vulnerability. Here, we initially examined voxel-wise differences in cortical function and structure using the largest multi-modal MRI data from 1660 MDD patients and 1341 controls. Combined with the Allen Human Brain Atlas, we then adopted transcription-neuroimaging spatial correlation and the newly developed ensemble-based gene category enrichment analysis to identify gene categories with expression related to cortical changes in MDD. Results showed that patients had relatively circumscribed impairments in local functional properties and broadly distributed disruptions in global functional connectivity, consistently characterized by hyper-function in associative areas and hypo-function in primary regions. Moreover, the local functional alterations were correlated with genes enriched for biological functions related to MDD in general (e.g., endoplasmic reticulum stress, mitogen-activated protein kinase, histone acetylation, and DNA methylation); and the global functional connectivity changes were associated with not only MDD-general, but also brain-relevant genes (e.g., neuron, synapse, axon, glial cell, and neurotransmitters). Our findings may provide important insights into the transcriptomic signatures of regional cortical vulnerability to MDD.


Assuntos
Transtorno Depressivo Maior , Transcriptoma , Humanos , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/fisiopatologia , Feminino , Masculino , Adulto , Córtex Cerebral/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética , Perfilação da Expressão Gênica
11.
Front Oncol ; 13: 1272090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239634

RESUMO

Introduction: Solitary fibrous tumor (SFT) represents a fibroblastic neoplasm exhibiting NAB2::STAT6 gene rearrangement, displaying diverse clinical manifestations, spanning from benign to malignant. To predict prognosis, the modified (four-variable) Demicco (mDemicco) model was introduced. This investigation aims to authenticate the mDemicco risk model's precision in Asian patients while investigating the clinicopathological and molecular factors linked to the prognosis of extrameningeal SFTs. Methods: Clinicopathological data from 111 extrameningeal SFT cases in East China, covering the period from 2010 to 2020, were thoroughly analyzed. The tumors were classified using the mDemicco model. Immunohistochemical evaluation of P16 and P53, molecular detection of TP53 and TERT promoter mutation, and fluorescence in situ hybridization for CDKN2A gene alterations were performed. Statistical methods were utilized to assess the associations between clinicopathological or molecular factors and prognosis. Results: Histologically, only one parameter, the mitotic count, exhibited a statistical correlation with progression-free survival (PFS) and overall survival (OS). During the Kaplan-Meier analysis, the variation in PFS among the different risk groups exhibited a notable trend towards statistical significance. Nevertheless, 3 out of 74 patients classified as low-risk SFTs and 7 out of 21 patients classified as intermediate-risk exhibited disease progression. Among the 5 patients with TP53 mutations and/or mutant-type P53 immunophenotype, 3 experienced disease progression, including 2 intermediate-risk patients. Additionally, among the 4 patients with TERT promoter mutations who were followed up, 3 showed progression, including 2 intermediate-risk patients. Moreover, it was observed that hemizygous loss of CDKN2A was detected in more than 30% of one case, yet the patient exhibited a favorable survival outcome. Conclusion: The mDemicco risk model exhibits certain limitations when dealing with smaller tumor sizes, younger age groups, and occurrences of malignant and dedifferentiated SFTs. Furthermore, molecular factors, such as TP53 or TERT promoter mutations, may identify intermediate-risk SFTs with poorer prognoses.

12.
Psychoradiology ; 2(1): 32-42, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38665141

RESUMO

Despite a growing neuroimaging literature on the pathophysiology of major depressive disorder (MDD), reproducible findings are lacking, probably reflecting mostly small sample sizes and heterogeneity in analytic approaches. To address these issues, the Depression Imaging REsearch ConsorTium (DIRECT) was launched. The REST-meta-MDD project, pooling 2428 functional brain images processed with a standardized pipeline across all participating sites, has been the first effort from DIRECT. In this review, we present an overview of the motivations, rationale, and principal findings of the studies so far from the REST-meta-MDD project. Findings from the first round of analyses of the pooled repository have included alterations in functional connectivity within the default mode network, in whole-brain topological properties, in dynamic features, and in functional lateralization. These well-powered exploratory observations have also provided the basis for future longitudinal hypothesis-driven research. Following these fruitful explorations, DIRECT has proceeded to its second stage of data sharing that seeks to examine ethnicity in brain alterations in MDD by extending the exclusive Chinese original sample to other ethnic groups through international collaborations. A state-of-the-art, surface-based preprocessing pipeline has also been introduced to improve sensitivity. Functional images from patients with bipolar disorder and schizophrenia will be included to identify shared and unique abnormalities across diagnosis boundaries. In addition, large-scale longitudinal studies targeting brain network alterations following antidepressant treatment, aggregation of diffusion tensor images, and the development of functional magnetic resonance imaging-guided neuromodulation approaches are underway. Through these endeavours, we hope to accelerate the translation of functional neuroimaging findings to clinical use, such as evaluating longitudinal effects of antidepressant medications and developing individualized neuromodulation targets, while building an open repository for the scientific community.

15.
Fundam Res ; 2(2): 177, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38933167
16.
Arq. neuropsiquiatr ; 74(11): 881-886, Nov. 2016. tab
Artigo em Inglês | LILACS | ID: biblio-827985

RESUMO

ABSTRACT The complement system has been confirmed to play an increasingly important role in ischemic stroke (IS). This study aimed to determine whether the single-nucleotide polymorphism of the complement 5 (C5) gene independently influences the occurrence, severity, and long-term outcome of IS in Chinese patients. Methods C5 rs17611 genetic variants were investigated in 494 IS patients and 330 control individuals .Ischemic stroke was classified into subtypes and patients were assessed 90 days post-stroke with the modified Rankin Scale to determine stroke outcome. Results The presence of C5 polymorphism was associated with the incidence of large artery atherosclerosis (LAA)-subtype IS (n =2 00; p = 0.031), which even persisted after adjustment for covariates (OR = 1.518; 95%CI = 1.093–2.018; p = 0.013). However, no association was found between genotypes and the severity and outcome of stroke (p = 0.978; p = 0.296). Conclusions The C5 polymorphism might contribute to the risk of LAA-subtype IS independently of other known risk predictors.


RESUMO Já se confirmou que o sistema do complemento exerce um papel cada vez mais importante nos acidentes vasculares cerebrais isquêmicos. Este estudo teve o objetivo de determinar se o polimorfismo de nucleotídeo único (SNP) do gene codificador do componente 5 (C5) influencia de forma independente a ocorrência, a severidade e o desfecho em longo prazo do acidente vascular cerebral isquêmico (AVCI) em pacientes chineses. Métodos Variantes genéticas rs17611 do C5 foram investigadas em 494 pacientes com AVCI e em 330 indivíduos controles. O AVCI foi classificado em subtipos e os pacientes foram avaliados 90 dias após o acidente vascular, através da Escala Modificada de Rankin (mRS), para determinação do desfecho do acidente. Resultados A presença de polimorfismo do C5 foi associada à incidência de AVCI do subtipo com aterosclerose de grandes artérias (AGA) (n = 200; p = 0,031), que persistiu mesmo após os ajustes de covariáveis (RP = 1,518; 95% IC = 1,093–2,018; p = 0,013). Entretanto, nenhuma associação foi observada entre os genótipos e a severidade ou o desfecho do acidente vascular (p = 0,978; p = 0,296). Conclusões O polimorfismo do C5 pode contribuir para o risco de AVCI do tipo com AGA, independentemente de outros riscos preditores conhecidos.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Complemento C5/genética , Acidente Vascular Cerebral/genética , Polimorfismo de Nucleotídeo Único , Índice de Gravidade de Doença , China , Predisposição Genética para Doença/genética , Povo Asiático/genética , Aterosclerose/genética , Estudos de Associação Genética
17.
Braz. dent. j ; 26(2): 198-202, Mar-Apr/2015. graf
Artigo em Inglês | LILACS | ID: lil-741207

RESUMO

The aims of the present study were to describe an impression method of "inner circular sealing area" and to evaluate the effect of the method on retention, aesthetics and comfort of complete dentures, which lack labial base for patients with maxillary protrusions. Three patients were subjected to the experiment, and two sets of complete maxillary dentures were made for each patient; the first set was made without labial base via an inner circular sealing area method (experimental group) and the second had an intact base that was made with conventional methods (control group). Retention force tests were implemented with a tensile strength assessment device to assess the retention and a visual analogue scale (VAS) was used to evaluate the comfort between the two groups. Results showed larger retention force, better aesthetics and more comfort in the experimental group. The improved two-step impression method formed an inner circular sealing area that prevented damage to the peripheral border seal effect of the denture caused by incomplete bases and obtained better denture retention.


O objetivo deste caso foi descrever um método de impressão por "área de selamento circular interno" e avaliar o efeito deste método na retenção, estética e conforto de próteses totais sem base labial para pacientes com protrusão maxilar. Três pacientes foram objeto desta experiência e foram feitas duas próteses maxilares completas para cada um deles; a primeira foi elaborada sem base labial pelo método de área de selamento circular interno (grupo experimental) e a outra teve uma base feita pelo método convencional (grupo controle). Foram realizados testes de retenção com estudo de tensão para avaliar a retenção e para avaliação do conforto dos dois grupos, foi empregada a escala analógica visual (EAV). Os resultados demonstraram que o grupo experimental apresentou força de retenção maior, estética melhor e mais conforto. O método modificado de impressão em duas etapas formou uma área de selamento circular interno que evitou danos ao selamento periférico causados por bases incompletas e obteve melhor retenção da prótese.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Retenção de Dentadura/métodos , Prótese Total , Técnica de Moldagem Odontológica , Planejamento de Dentadura , Estética Dentária
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