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1.
Physiol Plant ; 175(4): e13954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37318225

RESUMO

MYB transcription factor (TF) is one of the largest superfamilies that play a vital role in multiple plant biological processes. However, the MYB family has not been comprehensively identified and functionally verified in Cajanus cajan, which is the sixth most important legume crop. Here, 170 CcR2R3-MYBs were identified and divided into 43 functional subgroups. Segmental and tandem duplications and alternative splicing events were found and promoted the expansion of the CcR2R3-MYB gene family. Functional prediction results showed that CcR2R3-MYBs were mainly involved in secondary metabolism, cell fate and identity, developmental processes, and responses to abiotic stress. Cis-acting element analysis of promoters revealed that stress response elements were widespread in the above four functional branches, further suggesting CcR2R3-MYBs were extensively involved in abiotic stress response. The transcriptome data and qRT-PCR results indicated that most of the CcR2R3-MYB genes responded to various stresses, of which the expression of CcMYB107 was significantly induced by drought stress. Overexpression of CcMYB107 enhanced antioxidant enzyme activity and increased proline and lignin accumulation, thus improving the drought resistance of C. cajan. Furthermore, Overexpression of CcMYB107 up-regulated the expression of stress-related genes and lignin biosynthesis genes after drought stress. Our findings established a strong foundation for the investigation of biological function of CcR2R3-MYB TFs in C. cajan.


Assuntos
Cajanus , Genes myb , Cajanus/genética , Cajanus/metabolismo , Resistência à Seca , Lignina/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Filogenia
2.
Clin Oral Investig ; 27(8): 4173-4189, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37121943

RESUMO

BACKGROUND: Skeletal class III malocclusion has a diverse and complicated aetiology involving environmental and genetic factors. It is critical to correctly classify and define this malocclusion to be diagnosed and treated on a clinically sound basis. Thus, this study aimed to provide reliable and detailed measurements in a large ethnically homogeneous sample of Chinese adults to generate an adequate phenotypic clustering model to identify and describe the skeletal variation present in skeletal class III malocclusion. MATERIALS AND METHODS: This is a retrospective cross-sectional study in which 500 pre-treatments cone-beam computed tomography (CBCT) scans of patients with skeletal class III malocclusion (250 males and 250 females) were selected following specific selection criteria. Seventy-six linear, angular, and ratios measurements were three-dimensionally analysed using InVivo 6.0.3 software. These measurements were categorised into 47 skeletal, 18 dentoalveolar, and 11 soft tissue variables. Multivariate reduction methods: principal component analyses and cluster analyses were used to present the most common phenotypic groupings of skeletal class III malocclusion in Han ethnic group of Chinese adults. RESULTS: The principal component analysis revealed eight principal components accounted for 72.9% of the overall variation of the data produced from the seventy-six variables. The first four principal components accounted for 53.37% of the total variations. They explained the most variation in data and consisted mainly of anteroposterior and vertical skeletal relationships. The cluster analysis identified four phenotypes of skeletal class III malocclusion: C1, 34%; C2, 11.4%; C3, 26.4%; and C4, 28.2%. CONCLUSION: Based on three-dimensional analyses, four skeletal class III malocclusion distinct phenotypic variations were defined in a large sample of the adult Chinese population, showing the occurrence of phenotypic variation between identified clusters in the same ethnic group. These findings might serve as a foundation for accurate diagnosis and treatment planning of each cluster and future genetic studies to determine the causative gene(s) of each cluster.


Assuntos
Má Oclusão Classe III de Angle , Má Oclusão , Humanos , Masculino , Feminino , Análise de Componente Principal , Estudos Retrospectivos , Estudos Transversais , População do Leste Asiático , Má Oclusão Classe III de Angle/diagnóstico por imagem , Fenótipo , Análise por Conglomerados , Tomografia Computadorizada de Feixe Cônico , Cefalometria/métodos , Mandíbula
3.
Sensors (Basel) ; 23(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37300063

RESUMO

Compared to fixed orthodontic appliances with brackets, thermoplastic invisible orthodontic aligners offer several advantages, such as high aesthetic performance, good comfort, and convenient oral health maintenance, and are widely used in orthodontic fields. However, prolonged use of thermoplastic invisible aligners may lead to demineralization and even caries in most patients' teeth, as they enclose the tooth surface for an extended period. To address this issue, we have created PETG composites that contain piezoelectric barium titanate nanoparticles (BaTiO3NPs) to obtain antibacterial properties. First, we prepared piezoelectric composites by incorporating varying amounts of BaTiO3NPs into PETG matrix material. The composites were then characterized using techniques such as SEM, XRD, and Raman spectroscopy, which confirmed the successful synthesis of the composites. We cultivated biofilms of Streptococcus mutans (S. mutans) on the surface of the nanocomposites under both polarized and unpolarized conditions. We then activated piezoelectric charges by subjecting the nanocomposites to 10 Hz cyclic mechanical vibration. The interactions between the biofilms and materials were evaluated by measuring the biofilm biomass. The addition of piezoelectric nanoparticles had a noticeable antibacterial effect on both the unpolarized and polarized conditions. Under polarized conditions, nanocomposites demonstrated a greater antibacterial effect than under unpolarized conditions. Additionally, as the concentration of BaTiO3NPs increased, the antibacterial rate also increased, with the surface antibacterial rate reaching 67.39% (30 wt% BaTiO3NPs). These findings have the potential for application in wearable, invisible appliances to improve clinical services and reduce the need for cleaning methods.


Assuntos
Nanocompostos , Streptococcus mutans , Humanos , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química
4.
Prog Orthod ; 24(1): 25, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37455279

RESUMO

BACKGROUND: Maxillary molar distalization is a common technique used in the non-extraction treatment of Angle Class II malocclusion that can effectively correct the molar relationship and create spaces for anterior teeth alignment. However, this approach may also impact the temporomandibular joint (TMJ) due to predictable changes in the posterior vertical dimension. Despite its widespread use, Class II malocclusions correction by molar distalization with clear aligners has not been investigated for their effects on the TMJ. Therefore, this study aimed to analyze the impact of sequential molar distalization using clear aligners on the TMJ. METHODS: Three-dimensional CBCT scans of 23 non-growing patients (7 males, 16 females; mean age 29.8 ± 4.6 years) with skeletal class I or II malocclusion and a bilateral molar class II relationship treated by sequential upper molars distalization with orthodontic clear aligners (Invisalign, Align Technology, San Josè, Ca, USA). A total of 46 joints were examined before and after molar distalization using Anatomage InvivoDental 6.0.3. Linear and angular measurements of the mandibular joint were measured, including joint parameters, inclination, position, and the dimension of the condyle and articular fossa. In addition, 3D volumetric spaces of the joint were analyzed. All data were statistically analyzed by paired T test to determine the differences between the pre-and post-orthodontic procedures. RESULTS: No statistically significant differences were found in all primary effects resulting from maxillary molars distalization by clear aligners on TMJ components measurements and joint spaces between T0 and T1. Meanwhile, statistically significant differences were observed in the linear position of the upper molars and the molar relationship parameter with at least P ≤ 0.05. CONCLUSION: Treatment by sequential upper molars distalization with clear aligners does not lead to significant TMJ parameters changes in condyle and fossa spaces, dimensions, and positions.


Assuntos
Má Oclusão Classe II de Angle , Aparelhos Ortodônticos Removíveis , Técnicas de Movimentação Dentária , Adulto , Feminino , Humanos , Masculino , Má Oclusão , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Maxila/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Articulação Temporomandibular/diagnóstico por imagem , Técnicas de Movimentação Dentária/métodos , Tomografia Computadorizada de Feixe Cônico
5.
Dentomaxillofac Radiol ; 52(3): 20220346, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36695712

RESUMO

OBJECTIVES: This study aimed to determine the three-dimensional (3D) correlation between maxillomandibular complex parameters and pharyngeal airway dimensions in different sagittal and vertical malocclusions. METHODS: This retrospective cross-sectional study included the CBCT scans of 368 patients with a mean age of 23.81 ± 3.01 years. The patients were classified into three groups (skeletal Class I, II, and III). Each class group was divided into three subgroups based on vertical growth patterns (hypo-, normo-, and hyperdivergent). The maxillomandibular complex was evaluated in the three planes using 16 skeletal measurements. Naso-, oro-, hypo-, and total pharyngeal airway spaces were assessed in terms of width, volume, surface area, and minimum constricted area (MCA). Two-way ANOVA followed by the Bonferroni post-hoc test were used. RESULTS: The nasopharyngeal airway space was significantly lowest regarding sagittal and lateral widths in the skeletal Class III patients, the lowest volume and surface area were in hyperdivergent patients, and MCA was the highest in Class II and hypodivergent patients. The oro- and hypopharyngeal sagittal width, volume, surface area, and MCA were the lowest in the hyperdivergent patients, and oropharyngeal lateral width and hypopharyngeal sagittal width were the highest in skeletal Class III. The total pharyngeal volume, surface area, and MCA were the lowest in the hyperdivergent patients, and skeletal Class II patients had the lowest MCA. CONCLUSIONS: The pharyngeal airway dimensions differ with various sagittal and vertical malocclusions. These differences could apply to diagnosis, treatment planning, and possible changes following orthodontic/orthopedic or surgical treatment.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Má Oclusão , Humanos , Adulto Jovem , Adulto , Estudos Retrospectivos , Estudos Transversais , Tomografia Computadorizada de Feixe Cônico/métodos , Cefalometria/métodos , Faringe/diagnóstico por imagem , Má Oclusão/diagnóstico por imagem , Imageamento Tridimensional/métodos , Mandíbula/diagnóstico por imagem
6.
J Healthc Eng ; 2022: 1421586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36457590

RESUMO

Objective: To study the effect of the physiological anchorage control concept on anchorage molars in lingual and labial orthodontic techniques. Methods: Three-dimensional finite element models, including the right maxillary first molar, periodontal ligament, alveolar bone, and buccal tube, were established. The models were divided into the McLaughlin-Bennett-Trevisi (MBT™) straight-wire model with 0-degree maxillary first molar axial inclination and the physiologic anchorage Speewire system (PASS) model with -7-degree maxillary first molar axial inclination. Simulated sliding retraction forces (1 N, 1.5 N, and 2 N) were loaded on the buccal side and lingual side, and retraction forces (0.5 N, 0.75 N, and 1 N) were loaded on the buccal and lingual sides simultaneously. The displacements, principal stresses, and von Mises stresses of the periodontal ligament under different conditions were derived. Results: The anchorage molars showed different degrees of rotation, tipping, intrusion, and extrusion. As the force increased, these displacement trends also increased. The mesial displacement of the buccal + lingual force loading was less than that of the other two groups. Under the same force load method, the mesial displacement of the PASS group was less than that of the MBT group. Tilt movement increases the tensile stress of the distal cervical margin and root mesial apical third and the compressive stress of the mesial cervical margin and root distal apical third. The maximum stress of the periodontal ligament was less than that of the other two groups when the lingual force was loaded. Conclusion: The physiological anchorage control concept in lingual orthodontics provides better sagittal anchorage control than in labial orthodontics, but there is no significant difference numerically. Attention should be given to the control of torsion, torque, and arch width. Tilt movement increases the PDL stress of the cervical margin and root apical third. The sliding retraction force should be loaded lingually to maintain the force value of 1∼1.5 N.


Assuntos
Dente Molar , Língua , Humanos , Análise de Elementos Finitos , Movimento , Ligamento Periodontal
7.
J Mech Behav Biomed Mater ; 118: 104452, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33756417

RESUMO

The poor mechanical properties and the lack of antibacterial ability of hydrogels limit their applications as wound dressing. In this work, a novel and high strength polyvinyl alcohol (PVA)/tannic acid (TA) hydrogel with aramid nanofibers (ANFs) as the reinforcement was successfully fabricated. The surface composition and microstructure of the hydrogel were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The mechanical properties, water content and swelling behaviors, as well as the antibacterial abilities and biocompatibility of the prepared hydrogel were systematically analyzed as well. The results indicated that the prepared hydrogel showed excellent mechanical properties. The tensile strength and elongation of the prepared hydrogel can respectively reach 2.06 MPa and 950% owing to the formation of the multiple H bonds among PVA, ANFs and TA. What's more, PVA/ANFs/TA (PAT) hydrogel possessed shape memory and broad-spectrum antibacterial properties against S. aureus, E. coli and P. aeruginosa (100% antibacterial rate) at the concentration of 12 mg/mL. PAT hydrogels also had low cytotoxicity, affirming its potential application as wound dressing.


Assuntos
Nanofibras , Álcool de Polivinil , Antibacterianos/farmacologia , Bandagens , Escherichia coli , Hidrogéis , Staphylococcus aureus , Taninos , Cicatrização
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 36(2): 156-161, 2018 Apr 01.
Artigo em Zh | MEDLINE | ID: mdl-29779276

RESUMO

OBJECTIVE: The aim of this study is to build a digital dental model with cone beam computed tomography (CBCT), to fabricate a virtual model via 3D printing, and to determine the accuracy of 3D printing dental model by comparing the result with a traditional dental cast. METHODS: CBCT of orthodontic patients was obtained to build a digital dental model by using Mimics 10.01 and Geomagic studio software. The 3D virtual models were fabricated via fused deposition modeling technique (FDM). The 3D virtual models were compared with the traditional cast models by using a Vernier caliper. The measurements used for comparison included the width of each tooth, the length and width of the maxillary and mandibular arches, and the length of the posterior dental crest. RESULTS: 3D printing models had higher accuracy compared with the traditional cast models. The results of the paired t-test of all data showed that no statistically significant difference was observed between the two groups (P>0.05). CONCLUSIONS: Dental digital models built with CBCT realize the digital storage of patients' dental condition. The virtual dental model fabricated via 3D printing avoids traditional impression and simplifies the clinical examination process. The 3D printing dental models produced via FDM show a high degree of accuracy. Thus, these models are appropriate for clinical practice.


Assuntos
Modelos Dentários , Dente , Tomografia Computadorizada de Feixe Cônico , Humanos , Imageamento Tridimensional , Impressão Tridimensional
9.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 32(3): 246-51, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-25033639

RESUMO

OBJECTIVE: To investigate the changes in the craniofacial morphology ofdeepbite from childhood to adulthood using cross-sectional methods. To analyze the maxillofacial characteristics of adult deepbite. METHODS: The sample included 159 children (with average age of 12.47 years old) and 81 adults (with average age of21.76 years old) with class III deepbite. The control group consisted of51 normal individuals (with average age of 18.41 years old). Lateral cephalometric radiographs were taken and recorded in a computer through a scanner. Cephalometric measurements were conducted by using Winceph 7.0 software, and results were analyzed with SPSS 12.0 software. RESULTS: Significant differences between child and adult deepbite were observed in the following: N-ANS, ANS-Me, A-Ms, A-Ptm, Wits, Mo-Ms, Ii-Ii, A-B plane angle to the mandibular plane angle, Gonial angle, L1 to NB length, overjet, mandibular body to anterior cranial base, Mo-Mi, posterior facial height, U1 to NA length, Pog-Go, Cd-Go, occlusion plane angle to SN, and U1 to SN. In addition, significant differences between adult deepbite and normal occlusion were observed in SNB, ANB, convexity, APDI, ODI, Wits, A-B plane to mandibular plane, Gonial angle, overjet, mandibular body to anterior cranial base, S-Ptm, Mo-Mi U1 to SN; Pog-Go, Cd-Go, posterior cranial base, and occlusion plane to SN and posterior facial height. CONCLUSION: Deepbite patients have certain growth potential after puberty, but the sagittal relationship of their jaws exhibits no improvement. Adult deepbite patients exhibit significant problems in the vertical and sagittal jaw positions.


Assuntos
Oclusão Dentária , Maturidade Sexual , Adulto , Osso e Ossos , Cefalometria , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Mandíbula
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(1): 21-5, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23484295

RESUMO

OBJECTIVE: To investigate the effect of en-masse retraction of maxillary anterior teeth by rocking-chair archwire (RCA) in sliding mechanics. METHODS: The three dimensional finite element model of maxillary teeth was created based on spiral CT data of a patient by ANSYS software. The forces on each tooth and the torques on the six center of resistance (CR) of the anterior teeth induced by the deformation of RCA with different depth and anterior retraction hook (ARH) with different height were calculated when retracted from a mini-implant between the first molar and the second premolar. The movements of anterior teeth were observed combining different depth of RCA with different height of ARH. RESULTS: The clockwise torque in sliding mechanics to realize en-masse retraction of the anterior teeth could be counterbalanced by RCA of certain depth. The combination of 7.2 mm ARH and 2 mm RCA can be used to intrude and retract maxillary anterior teeth under the condition of applying mini-implant. CONCLUSION: The excessive retraction that usually exists in traditional treatments can be avoided by RCA in sliding mechanics and intrusion and torque control during anterior segment retraction can also be achieved by this method.


Assuntos
Análise de Elementos Finitos , Técnicas de Movimentação Dentária , Dente Pré-Molar , Humanos , Incisivo , Maxila , Dente Molar , Torque
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