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1.
Nano Lett ; 24(22): 6753-6760, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38708988

RESUMO

Recently, extensive research has been reported on the detection of metal nanoparticles using terahertz waves, due to their potential for efficient and nondestructive detection of chemical and biological samples without labeling. Resonant terahertz nanoantennas can be used to detect a small amount of molecules whose vibrational modes are in the terahertz frequency range with high sensitivity. However, the positioning of target molecules is critical to obtaining a reasonable signal because the field distribution is inhomogeneous over the antenna structure. Here, we combine an optical tweezing technique and terahertz spectroscopy based on nanoplasmonics, resulting in extensive controllable tweezing and sensitive detection at the same time. We observed optical tweezing of a gold nanoparticle and detected it with terahertz waves by using a single bowtie nanoantenna. Furthermore, the calculations confirm that molecular fingerprinting is possible by using our technique. This study will be a prestep of biomolecular detection using gold nanoparticles in terahertz spectroscopy.

2.
Diabetologia ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879617

RESUMO

AIMS/HYPOTHESIS: Glomerular lipid accumulation is a defining feature of diabetic kidney disease (DKD); however, the precise underlying mechanism requires further elucidation. Recent evidence suggests a role for proprotein convertase subtilisin/kexin type 9 (PCSK9) in intracellular lipid homeostasis. Although PCSK9 is present in kidneys, its role within kidney cells and relevance to renal diseases remain largely unexplored. Therefore, we investigated the role of intracellular PCSK9 in regulating lipid accumulation and homeostasis in the glomeruli and podocytes under diabetic conditions. Furthermore, we aimed to identify the pathophysiological mechanisms responsible for the podocyte injury that is associated with intracellular PCSK9-induced lipid accumulation in DKD. METHODS: In this study, glomeruli were isolated from human kidney biopsy tissues, and glomerular gene-expression analysis was performed. Also, db/db and db/m mice were used to perform glomerular gene-expression profiling. We generated DKD models using a high-fat diet and low-dose intraperitoneal streptozocin injection in C57BL/6 and Pcsk9 knockout (KO) mice. We analysed cholesterol and triacylglycerol levels within the kidney cortex. Lipid droplets were evaluated using BODIPY staining. We induced upregulation and downregulation of PCSK9 expression in conditionally immortalised mouse podocytes using lentivirus and siRNA transfection techniques, respectively, under diabetic conditions. RESULTS: A significant reduction in transcription level of PCSK9 was observed in glomeruli of individuals with DKD. PCSK9 expression was also reduced in podocytes of animals under diabetic conditions. We observed significantly higher lipid accumulation in kidney tissues of Pcsk9 KO DKD mice compared with wild-type (WT) DKD mice. Additionally, Pcsk9 KO mouse models of DKD exhibited a significant reduction in mitochondria number vs WT models, coupled with a significant increase in mitochondrial size. Moreover, albuminuria and podocyte foot process effacement were observed in WT and Pcsk9 KO DKD mice, with KO DKD mice displaying more pronounced manifestations. Immortalised mouse podocytes exposed to diabetic stimuli exhibited heightened intracellular lipid accumulation, mitochondrial injury and apoptosis, which were ameliorated by Pcsk9 overexpression and aggravated by Pcsk9 knockdown in mouse podocytes. CONCLUSIONS/INTERPRETATION: The downregulation of PCSK9 in podocytes is associated with lipid accumulation, which leads to mitochondrial dysfunction, cell apoptosis and renal injury. This study sheds new light on the potential involvement of PCSK9 in the pathophysiology of glomerular lipid accumulation and podocyte injury in DKD.

3.
Am J Gastroenterol ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912692

RESUMO

OBJECTIVES: Aggressive hydration using lactated Ringer's solution (LRS) prevents post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). Concerns of this strategy are large volume and lengthy hydration. Our study aimed to evaluate the efficacy of tailored aggressive hydration (TAH) for PEP prevention. METHODS: In this prospective, multicenter, double-blinded, randomized trial conducted across three tertiary Korean hospitals, patients who underwent ERCP for the first-time were randomly assigned (1:1) to tailored standard hydration (TSH) and TAH groups. The TSH group received 1.5 mL/kg/h LRS during and after ERCP, whereas the TAH group was administered a 20 mL/kg bolus post-ERCP and 3 mL/kg/h during and after the procedure. Both groups were assessed for elevated serum amylase levels and pain 4-6 h after ERCP. If both were absent, hydration was discontinued. If either was present, hydration was continued at the original rate until 8 h. The primary endpoint was PEP development and was analyzed on an intention-to-treat analysis. RESULTS: A total of 344 patients were randomly assigned to treatment groups (171 to the TSH group and 172 to the TAH group). PEP was observed in 9.4% (16/171) in the TSH group and 3.5% (6/172) in the TAH group (relative risk 0.37, 95% confidence interval 0.15-0.93, p = 0.03). No difference was identified between the two groups in terms of PEP severity (p = 0.80) and complications related to volume overload (p = 0.32). CONCLUSIONS: TAH according to the presence of abdominal pain or elevated serum amylase levels at 4-6 h after ERCP is safe and prevents PEP development.

4.
Endoscopy ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857618

RESUMO

BACKGROUND AND STUDY AIMS: Although lumen-apposing metal stents (LAMSs) have been increasingly used for walled-off necrosis (WON), their advantages over plastic stents (PS) in infected WON are unclear. We investigated the safety and efficacy of novel electrocautery-enhanced LAMS (EC-LAMS) for managing infected WON. PATIENTS AND METHODS: Patients who underwent endoscopic ultrasound-guided WON drainage were randomly assigned to the LAMS or PS groups. The primary outcome was the total number of direct endoscopic necrosectomy (DEN) procedures required to achieve clinical success. The secondary outcomes included technical success, clinical success, and adverse event occurrence. RESULTS: Forty-six patients were divided into the LAMS or PS groups (n=23 each). The total number of DEN procedures did not differ significantly between the PS (four procedures, interquartile range [IQR] 2.5-5.0) and LAMS groups (nine procedures, IQR: 8.0-9.0) (P=0.07). The LAMS group demonstrated a significantly higher clinical success rate than the PS group based on intention-to-treat analysis (100% vs. 73.9%, P=0.03) at 8 weeks but not at 4 weeks. No significant bleeding events were reported in the LAMS group, and one was reported in the PS group. CONCLUSIONS: We found no significant difference in the total number of DEN procedures between LAMS and PS for managing infected WON. The only statistically significant finding was a higher clinical success rate at 8 weeks for patients treated with EC-LAMS. The use of EC-LAMS did not result in any adverse events, such as bleeding or buried LAMS syndrome, within the study duration.

5.
J Gastroenterol Hepatol ; 38(4): 648-655, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36710432

RESUMO

BACKGROUND AND AIMS: Immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) is considered a biliary manifestation of IgG4-related diseases. However, there has been a controversy on the clinical outcomes according to the location of the involved bile duct. We therefore compared the clinical outcomes and long-term prognosis of IgG4-SC with proximal bile duct involvement (proximal IgG4-SC) and IgG4-SC with distal bile duct involvement (distal IgG4-SC). METHODS: We reviewed the data of patients with IgG4-SC that were prospectively collected at 10 tertiary centers between March 2002 and October 2020. Clinical manifestations, outcomes, association with autoimmune pancreatitis (AIP), steroid-responsiveness, and relapse of IgG4-SC were evaluated. RESULTS: A total of 148 patients (proximal IgG4-SC, n = 59; distal IgG4-SC, n = 89) were analyzed. The median age was 65 years (IQR, 56.25-71), and 86% were male. The two groups were similar in terms of jaundice at initial presentation (51% vs 65%; P = 0.082) and presence of elevated serum IgG4 (66% vs 70%; P = 0.649). The two groups showed significant differences in terms of steroid-responsiveness (91% vs 100%; P = 0.008), association with AIP (75% vs 99%; P = 0.001), and occurrence of liver cirrhosis (9% vs 1%; P = 0.034). During a median follow-up of 64 months (IQR, 21.9-84.7), the cumulative relapse-free survival was significantly different between the two groups (67% vs 79% at 5 years; P = 0.035). CONCLUSIONS: Relapse of IgG4-SC frequently occurred during follow-up. Proximal IgG4-SC and distal IgG4-SC had different long-term outcomes in terms of steroid-responsiveness, occurrence of liver cirrhosis, and recurrence. It may be advantageous to determine the therapeutic and follow-up strategies according to the location of bile duct involvement.


Assuntos
Doenças Autoimunes , Pancreatite Autoimune , Colangite Esclerosante , Humanos , Masculino , Idoso , Feminino , Colangite Esclerosante/complicações , Colangite Esclerosante/diagnóstico , Colangite Esclerosante/tratamento farmacológico , Imunoglobulina G , Doenças Autoimunes/complicações , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/tratamento farmacológico , Esteroides/uso terapêutico , Estudos de Coortes , Cirrose Hepática/tratamento farmacológico , Diagnóstico Diferencial , Estudos Multicêntricos como Assunto
6.
Sensors (Basel) ; 23(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36991786

RESUMO

In this study, a novel framework for the flight control of a morphing unmanned aerial vehicle (UAV) based on linear parameter-varying (LPV) methods is proposed. A high-fidelity nonlinear model and LPV model of an asymmetric variable-span morphing UAV were obtained using the NASA generic transport model. The left and right wing span variation ratios were decomposed into symmetric and asymmetric morphing parameters, which were then used as the scheduling parameter and the control input, respectively. LPV-based control augmentation systems were designed to track the normal acceleration, angle of sideslip, and roll rate commands. The span morphing strategy was investigated considering the effects of morphing on various factors to aid the intended maneuver. Autopilots were designed using LPV methods to track commands for airspeed, altitude, angle of sideslip, and roll angle. A nonlinear guidance law was coupled with the autopilots for three-dimensional trajectory tracking. A numerical simulation was performed to demonstrate the effectiveness of the proposed scheme.

7.
Sensors (Basel) ; 22(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35458927

RESUMO

The advancement of science and technology has brought innovation in the dental field [...].


Assuntos
Inteligência Artificial , Tomografia Computadorizada de Feixe Cônico Espiral , Odontologia , Tecnologia
8.
Am J Orthod Dentofacial Orthop ; 162(1): 42-50, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35221139

RESUMO

INTRODUCTION: The study aimed to evaluate the morphologic changes in the pharyngeal airway after bimaxillary surgery in skeletal Class III malocclusion patients with or without asymmetry. We also analyzed the correlation between positional changes in the menton, hyoid bone, and changes in the dimensions of the pharyngeal airway. METHODS: We included 32 patients with skeletal Class III malocclusion who underwent bimaxillary surgery. There were 16 subjects in the symmetry group (10 male, 6 female; mean age, 22.44 ± 5.14 years), and 16 in the asymmetry group (10 male, 6 female; mean age, 21.38 ± 4.62 years). Preoperative and postoperative (2 months after surgery) cone-beam computed tomography scans were taken and then analyzed by comparing postoperative changes in each group. RESULTS: The anteroposterior lengths at the uvula level (P2L) and epiglottis level (P3L) were significantly decreased in the symmetry group. The P2L was also significantly decreased in the asymmetry group, and a difference in the P3L was observed. However, there was no significant change in the width at the uvula level (P2W) and epiglottis level (P3W) in the symmetry group. In contrast, in the asymmetry group, P2W and P3W were significantly decreased. The cross-sectional ratio was significantly decreased P2 (P2L/P2W) and P3 (P3L/P3W) in the symmetry group. However, a statistically significant decrease occurred only at P3 in the asymmetry group. Anteroposterior positional changes of the menton and P2L (r = -0.370; P <.05), P3L (r = -0.414; P <0.05), and P3L/P3W (r = -0.361; P <0.05) were correlated. CONCLUSIONS: Differences in the morphologic features of the pharyngeal airway after bimaxillary surgery was observed in both the symmetry and asymmetry groups. Bimaxillary surgery with a mandibular setback in patients with skeletal Class III malocclusion worsened morbidity of the elliptical structure of the pharyngeal airway. However, it worsened less in the asymmetry group than in the symmetry group.


Assuntos
Má Oclusão Classe III de Angle , Procedimentos Cirúrgicos Ortognáticos , Faringe , Adolescente , Adulto , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Assimetria Facial , Feminino , Humanos , Osso Hioide/diagnóstico por imagem , Masculino , Má Oclusão Classe III de Angle/cirurgia , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Faringe/diagnóstico por imagem , Adulto Jovem
9.
Am J Orthod Dentofacial Orthop ; 161(2): 208-219, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34753591

RESUMO

INTRODUCTION: Controlling transverse discrepancies is necessary to ensure stable and functional occlusion. Altered molar inclinations can camouflage the transverse relationship. The purpose of this research was to evaluate the maxillomandibular relationship of the center of resistance (CR) of the arch form created by the CR of teeth and compare these CR arch forms by their skeletal patterns. METHODS: Sixty patients with minor crowding and normal posterior overjet were divided into 3 groups according to ANB angle: skeletal Class I group had ANB angle between 0° and 4° (n = 20), skeletal Class II group had ANB angle >4° (n = 20), and skeletal Class III group had ANB angle <0° (n = 20). The 3-dimensional coordinates of the CR were estimated using cone-beam computed tomography images and projected on the CR occlusal plane to obtain the 2-dimensional coordinates. The CR arch forms were constructed and evaluated using Matlab (MathWorks, Natick, Mass). RESULTS: On comparing maxillomandibular CR arch form widths, the maxilla was significantly larger than the mandible of the canine and first premolar. The mandible was larger in the first molar of the skeletal Class III group. The maxillomandibular CR arch form width ratios were between 0.97 and 1.35. On comparing maxillomandibular CR arch form areas, the maxilla was significantly larger than the mandible in the anterior segment, and the mandible was larger in the posterior segment. The ratios were between 0.86 and 2.25. In between-group comparison, the skeletal Class III group showed significantly greater arch forms in the mandible. CONCLUSIONS: CR arch forms had significant maxillomandibular differences throughout the arch. The maxillomandibular ratios could be a reference for site-specific transverse discrepancy analysis.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Má Oclusão , Cefalometria , Humanos , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem
10.
Kidney Int ; 100(3): 570-584, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34051264

RESUMO

Ischemia-reperfusion injury is a major cause of acute kidney injury. Recent studies on the pathophysiology of ischemia-reperfusion-induced acute kidney injury showed that immunologic responses significantly affect kidney ischemia-reperfusion injury and repair. Nuclear factor (NF)-ĸB signaling, which controls cytokine production and cell survival, is significantly involved in ischemia-reperfusion-induced acute kidney injury, and its inhibition can ameliorate ischemic acute kidney injury. Using EXPLOR, a novel, optogenetically engineered exosome technology, we successfully delivered the exosomal super-repressor inhibitor of NF-ĸB (Exo-srIĸB) into B6 wild type mice before/after kidney ischemia-reperfusion surgery, and compared outcomes with those of a control exosome (Exo-Naïve)-injected group. Exo-srIĸB treatment resulted in lower levels of serum blood urea nitrogen, creatinine, and neutrophil gelatinase-associated lipocalin in post-ischemic mice than in the Exo-Naïve treatment group. Systemic delivery of Exo-srIĸB decreased NF-ĸB activity in post-ischemic kidneys and reduced apoptosis. Post-ischemic kidneys showed decreased gene expression of pro-inflammatory cytokines and adhesion molecules with Exo-srIĸB treatment as compared with the control. Intravital imaging confirmed the uptake of exosomes in neutrophils and macrophages. Exo-srIĸB treatment also significantly affected post-ischemic kidney immune cell populations, lowering neutrophil, monocyte/macrophage, and T cell frequencies than those in the control. Thus, modulation of NF-ĸB signaling through exosomal delivery can be used as a novel therapeutic method for ischemia-reperfusion-induced acute kidney injury.


Assuntos
Injúria Renal Aguda , Exossomos , Traumatismo por Reperfusão , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Animais , Rim , Camundongos , Camundongos Endogâmicos C57BL , Inibidor de NF-kappaB alfa , Traumatismo por Reperfusão/prevenção & controle
11.
Orthod Craniofac Res ; 24 Suppl 1: 39-47, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33237622

RESUMO

Biocreative Orthodontic Strategy (BOS) is designed to establish a physiologically stable occlusion in harmony with masticatory and TMJ function and healthy supporting tissues with strategic use of temporary skeletal anchorage devices (TSADs). This narrative review surveys current research that demonstrates how BOS with TSADs uses a target approach to overcome the limitations experienced with conventional orthodontic treatment. A narrative review article including research on TSADs orthodontics in the permanent dentition. This review is a brief survey of five BOS principles for contemporary TSAD orthodontics: elegant selection of TSADs, bracket prescription to enhance TSAD orthodontics, antero-posterior dimension control, transverse dimension control and airway control issues. Severe malocclusion and craniofacial dysmorphology can be treated with Biocreative Orthodontic Strategy with a minimum number of TSADs. In order to achieve successful treatment outcome using TSADs, it is critical to understand the key diagnosis and treatment principles of BOS and how to develop a target approach for the tooth and bone movement.


Assuntos
Má Oclusão , Procedimentos de Ancoragem Ortodôntica , Ortodontia , Oclusão Dentária , Humanos , Má Oclusão/terapia , Técnicas de Movimentação Dentária
12.
J Appl Clin Med Phys ; 22(6): 83-91, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34028956

RESUMO

BACKGROUND AND AIMS: A potential method to reduce gastrointestinal toxicity during radiation therapy in pancreatic head cancer is to create a physical space between the head of the pancreas (HOP) and the duodenum. To date, there have been early reports on the feasibility of endoscopic ultrasound (EUS)-guided hydrogel injection into the interface between the HOP and the duodenum to increase the peri-pancreatic space for radiotherapy. We aimed to evaluate the technical feasibility of EUS-guided hydrogel injection for the creation of space at the peri-pancreatic interface in a cadaveric model. METHODS: Baseline abdominal computerized tomography (CT) was performed on three unfixed cadaveric specimens. The hydrogel was injected transduodenally into the interface between the HOP and duodenum using linear-array EUS and a 19G needle for fine needle aspiration (FNA). This procedure was repeated along the length of the HOP. CT imaging and gross dissection were performed after the procedure to confirm the localization of the hydrogel and to measure the distance between the HOP and the duodenum. RESULTS: All cadavers underwent successful EUS-guided injection of the hydrogel. Cadavers 1, 2, and 3 were injected with 9.5, 27, and 10 cc of hydrogel, respectively; along the HOP, the formation of the peri-pancreatic space was a maximum size of 11.77, 13.20, and 12.89 mm, respectively. The hydrogel injections were clearly visualized as hyperechoic bullae during EUS and on post-procedure CT images without any artifacts in all cases. CONCLUSIONS: We demonstrated that EUS-guided delivery of hydrogel is feasible, and that it increases the peri-pancreatic space in a cadaveric model. The polyethylene glycol (PEG) hydrogel was clearly visible on EUS and CT, without significant artifacts. This may lead to new treatment approaches for pancreatic carcinomas.


Assuntos
Hidrogéis , Neoplasias Pancreáticas , Cadáver , Endossonografia , Humanos , Pâncreas/diagnóstico por imagem
13.
Sensors (Basel) ; 21(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502665

RESUMO

The aim of this study was to evaluate periodontal risk factors with oral health habits and fluorescent plaque index (FPI) using quantitative light-induced fluorescence (QLF) images, and to evaluate their effect on the degree of radiographic bone loss (RBL). Selected were 276 patients over 19 years of age to complete the questionnaire for oral health habit and take QLF images, periapical and panoramic radiographs. Oral health habit score, age, and sex showed a statistically significant correlation with FPI. FPI showed a lower value as the oral health habit score increased and the age decreased. Moreover, females showed lower FPI values than did males. RBL showed a statistically significant positive correlation with age but did not show any correlation with oral health habit scores and sex. There was no correlation between FPI and RBL. The results of this study suggest that the clinical use of QLF allows plaque detection by non-invasive procedures and can aid in a more objective estimation for oral hygiene status.


Assuntos
Fluorescência Quantitativa Induzida por Luz , Feminino , Hábitos , Humanos , Masculino , Saúde Bucal , Estudos Retrospectivos , Fatores de Risco
14.
Sensors (Basel) ; 21(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34502801

RESUMO

Accurate bracket placement is essential for successful orthodontic treatment. An indirect bracket bonding system (IDBS) has been developed to ensure proper bracket positioning with three-dimensional computer-aided transfer jigs. The purpose of this study was to investigate the accuracy of bracket positioning by a one-body transfer jig according to the tooth type and presence/absence of a resin base. In total, 506 teeth from 20 orthodontic patients were included in this study. After initial dental models were scanned, virtual setup and bracket positioning procedures were performed with 3D software. Transfer jigs and RP models were fabricated with a 3D printer, and brackets were bonded to the RP model with or without resin base fabrication. The best-fit method of 3D digital superimposition was used to evaluate the lineal and angular accuracy of the actual bracket position compared to a virtual bracket position. Although all the measurements showed significant differences in position, they were clinically acceptable. Regarding the tooth types, premolars and molars showed higher accuracy than anterior teeth. The presence or absence of a resin base did not consistently affect the accuracy. In conclusion, the proper application of IDBS should be performed considering the errors, and resin base fabrication might not be essential in ensuring high-accuracy IDBS.


Assuntos
Braquetes Ortodônticos , Dente , Humanos , Modelos Dentários , Dente/diagnóstico por imagem
15.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445758

RESUMO

This study was designed to develop and verify a fully automated cephalometry landmark identification system, based on multi-stage convolutional neural networks (CNNs) architecture, using a combination dataset. In this research, we trained and tested multi-stage CNNs with 430 lateral and 430 MIP lateral cephalograms synthesized by cone-beam computed tomography (CBCT) to make a combination dataset. Fifteen landmarks were manually and respectively identified by experienced examiner, at the preprocessing phase. The intra-examiner reliability was high (ICC = 0.99) in manual identification. The results of prediction of the system for average mean radial error (MRE) and standard deviation (SD) were 1.03 mm and 1.29 mm, respectively. In conclusion, different types of image data might be the one of factors that affect the prediction accuracy of a fully-automated landmark identification system, based on multi-stage CNNs.


Assuntos
Pontos de Referência Anatômicos , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Redes Neurais de Computação , Anormalidades Craniofaciais/diagnóstico por imagem , Bases de Dados Factuais , Humanos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799632

RESUMO

High orthodontic forces and various directions of applied forces can be associated with loosening of the screw anchorage in the bone. Screw designs have been modified to increase the stability of the miniscrews. This research evaluates the influence of three-designs on the stability of orthodontic miniscrews. A conventionally cylinder-type miniscrew design (Bio-Action screw, Jin-Biomed co., Bucheon, Korea) was set as a control, and three conditions were studied based on modifications of this control design. Condition-1 has narrowed threads in the upper part of the screw; Condition-2 has a notch at the middle part; and Condition-3 has the combination of Condition-1 and Condition-2. The moment required to unwind the miniscrew to five degrees is tested, and the moment generated at the cortical bone and the trabecular bone were calculated with finite element analysis. Compared to the control, all three conditions showed a higher moment required to unwind the miniscrew and a higher moment generated at the cortical bone. At the trabecular bone, condition-2 and -3 showed higher moment than the control, and condition-1 showed similar moment to the control. Condition-3 required a higher overall moment to unwind the miniscrew. These findings validate the design modifications used to increase the rotational resistance.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Parafusos Ósseos , Análise de Elementos Finitos , República da Coreia , Titânio
17.
Sensors (Basel) ; 21(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070904

RESUMO

The orthodontic miniscrew is driven into bone in a clockwise direction. Counter-clockwise rotational force applied to the implanted miniscrew can degrade the stability. The purpose of this three-dimensional finite element study was to figure out the effect of shifting the miniscrew head hole position from the long axis. Two miniscrew models were developed, one with the head hole at the long axis and the other with an eccentric hole position. One degree of counter-clockwise rotation was applied to both groups, and the maximum Von-Mises stress and moment was measured under various wire insertion angles from -60° to +60°. All Von-Mises stress and moments increased with an increase in rotational angle or wire insertion angle. The increasing slope of moment in the eccentric hole group was significantly higher than that in the centric hole group. Although the maximum Von-Mises stress was higher in the eccentric hole group, the distribution of stress was not very different from the centric hole group. As the positive wire insertion angles generated a higher moment under a counter-clockwise rotational force, it is recommended to place the head hole considering the implanting direction of the miniscrew. Clinically, multidirectional and higher forces can be applied to the miniscrew with an eccentric head hole position.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Parafusos Ósseos , Análise de Elementos Finitos , Fenômenos Mecânicos , Estresse Mecânico
18.
Sensors (Basel) ; 21(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33451097

RESUMO

The aim of this preliminary study was to evaluate the short-term changes of occlusal contacts and muscle activity after orthodontic treatment during the use of a multi-layer clear retainer. Evaluation was done with the T-scan and BioEMG systems. A total of 18 subjects were included, who were evaluated at three time intervals-T0 at debonding, T1 at one month after retainer delivery, and T2 at four months after retainer delivery. The T-scan and electromyography (EMG) data were recorded simultaneously. The T-scan system recorded the occlusion time, disclusion time and force distribution. The EMG waves were quantified by calculating the asymmetry index and activity index. The time variables changed but not significantly. Occlusal force decreased in the anterior dentition and increased in the posterior dentition during T0-T2. There was no clear evidence of a relationship between unbalanced occlusal forces and muscle activity. In most subjects, the temporalis anterior muscle was more dominant than the masseter muscle. From this preliminary computerized study, there were no significant changes in the state of the occlusion or muscle activity during the short-term retention period.


Assuntos
Músculo Masseter , Adolescente , Adulto , Força de Mordida , Eletromiografia , Feminino , Humanos , Masculino , Músculo Temporal , Dente , Adulto Jovem
19.
Int J Mol Sci ; 22(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073071

RESUMO

Gastric cancer is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. Histone deacetylase (HDAC) inhibitors are a new class of cytostatic agents available for the treatment of various cancers and diseases. Although numerous clinical and pre-clinical trials on the anticancer effects of panobinostat have been conducted, only a few reports have investigated its efficacy in gastric cancer. The present study aimed to investigate the effects of panobinostat in gastric cancer cells. Panobinostat significantly inhibited the cell viability and proliferation of the gastric cancer cell lines SNU484 and SNU638 in a dose-dependent manner; it reduced the colony-forming ability of these cells. Moreover, it induced apoptosis as indicated by increased protein levels of cleaved poly ADP-ribose polymerase and cleaved caspase-3. Panobinostat induced the G2/M cell cycle arrest in SNU484 and SNU638 cells and subsequently decreased the G2/M phase regulatory-associated protein expression of p-Wee1, Myt1, and Cdc2. Furthermore, panobinostat significantly inhibited the metastasis of SNU484 and SNU638 cells by regulating the expression of MMP-9 and E-cadherin. Further, it decreased the protein levels of p-Akt and forkhead box protein M1 (FOXM1). These effects were reversed by the Akt agonist SC79 and were accelerated by the Akt inhibitor LY2940002. Moreover, tumor growth in xenograft animal experiments was suppressed by panobinostat. These results indicated that panobinostat inhibits the proliferation, metastasis, and cell cycle progression of gastric cancer cells by promoting apoptosis and inactivating Akt/FOXM1 signaling. Cumulatively, our present study suggests that panobinostat is a potential drug for the treatment of gastric cancer.


Assuntos
Antineoplásicos , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Panobinostat , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Proteína Forkhead Box M1/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Camundongos , Metástase Neoplásica/tratamento farmacológico , Panobinostat/farmacologia , Panobinostat/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo
20.
Am J Orthod Dentofacial Orthop ; 160(6): 853-861, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34756786

RESUMO

INTRODUCTION: The purpose of this study was to analyze the treatment effects after molar distalization using modified C-palatal plates with and without second molar eruption and to evaluate the three-dimensional position of the molars during long-term retention using cone-beam computed tomography. METHODS: The study sample comprised 74 third molars in 42 patients. Twenty-seven adolescent patients (mean age, 12.6 years) having 48 maxillary third molars were divided into 2 groups according to the eruption of their second molars: 15 patients with second molar eruption (group 1) and 12 patients without second molar eruption (group 2). Pretreatment, posttreatment, and long-term data (mean, 5.2 years) from cone-beam computed tomography were scanned and compared with control groups. RESULTS: There was less tipping movement of the first and second molars (0.94° and 3.22°) and distal tipping movement of the third molars (8.91°) in group 1 than in group 2 (4.36°, 7.39°, and 3.08°, respectively), but the treatment time was shorter and the positional change of the third molars was insignificant in group 2. In the long-term, the second molars fully erupted after distalization in group 2, and there was no difference in the third molar position between group 1, group 2, and the control group, except for the vertical position of the third molars in group 1. CONCLUSIONS: In the long-term, the second molars fully erupted after distalization, and the third molars were in a favorable position. Therefore, these findings suggest that clinicians do not need to extract developing third molars before distalization in adolescents.


Assuntos
Má Oclusão Classe II de Angle , Técnicas de Movimentação Dentária , Adolescente , Cefalometria , Criança , Humanos , Maxila/diagnóstico por imagem , Dente Molar/diagnóstico por imagem
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