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1.
J Endod ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642733

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the effect of side flattening of cutting flutes on the cyclic resistance and torsional resistance of nickel-titanium files. METHODS: Both novel flattened Platinum V.EU (PL) and standard non-flattened CC Premium V.EU (CC) rotaries were tested. For cyclic fatigue tests, all the files were rotated in an artificial root canal with a curvature of 45° and a radius of 6.06 mm at 300 rpm (n = 15 in each group). The number of cycles to failure (NCF) was calculated. For torsional tests, the files were rotated at 2 rpm clockwise until fracture occurred. The maximum torque value at fracture was measured and the toughness and distortion angle were computed. Subsequently, five fragments were randomly selected in each experiment, the cross-section and longitudinal direction of the fragments were photographed using a scanning electron microscope. An unpaired t-test was performed at a significance level of 95%. RESULTS: There was a statistically significant difference in NCF between CC and PL (P < .05). CC showed higher NCF than PL. There was no statistically significant difference between CC and PL with regards to the parameters related to torsional resistance (distortion angle, ultimate strength, and toughness) (P > .05). CONCLUSION: Within the limitations of this study, side flattening of the file did not improve cyclic resistance or torsional resistance of the files. As side flattening may reduce a file's cyclic resistance, such files should be used with caution in clinical practice.

2.
IEEE Trans Vis Comput Graph ; 30(5): 2464-2473, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38437126

RESUMO

Redirected walking (RDW) enables users to walk naturally within a virtual environment that is larger than the physical environment. Recently, several artificial potential field (APF) and alignment-based redirected controllers have been developed and have been demonstrated to significantly outperform conventional controllers. APF Steer-to-Gradient (APF-S2G) and APF Redirected Walking (APF-RDW) utilize the negative gradient and the total force vector, respectively, which are localized to the user's position. These vectors usually point towards the opposite wall when the user is in corridors, resulting in frequent resets within those regions. This paper introduces the APF Steer-to-Target (APF-S2T), a redirected controller that first finds the target sample point with the lowest score in the user's walkable area in both physical and virtual environments. The score of a sample point is determined by the APF value at the point and the distance from the user's position. The direction from the user's position to the target point is then used as the steering direction for setting RDW gains. We conducted a simulation-based evaluation to compare APF-S2T, APF-S2G, APF-RDW, Visibility Polygon-based alignment (Vis.-Poly.) and Alignment-Optimized controllers in terms of the number of resets and the average distance between resets. The results indicated that APF-S2T significantly outperformed the state-of-the-art controllers.

3.
J Endod ; 50(4): 520-526, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311116

RESUMO

INTRODUCTION: This study aimed to evaluate the effects from the memory-triple (MT) heat treatment on the fatigue resistance of the Reciproc by comparison with the file systems of same geometry. METHODS: Reciproc files subjected to MT heat treatment technology were designated as Group RMT and were compared with the original Reciproc (Group REC) and Reciproc Blue (Group REB). Each NiTi file from 3 groups (n = 15) was operated reciprocally with a repetitive up-and-down movement in the curved canal with 4 mm of pecking distance inside of the simulated canal at body temperature. When each file fractured, the time until fracture was recorded. The length of the fractured fragment was measured. Fractured fragments were observed under scanning electron microscope (SEM) to evaluate the topographic features of the surface. Differential scanning calorimetry (DSC) analysis was performed to estimate phase transformation temperatures. One-way analysis of variance and Duncan post hoc comparison were applied to compare among the groups at a significance level of 95%. RESULTS: RMT showed significantly higher fracture resistance (P < .05), whereas there was no difference in fatigue resistance between REC and REB. SEM examination showed the files from the 3 groups had similar topographic features. RMT showed a peak of austenite peak (Ap) at a temperature (52°C) higher than body temperature, whereas REC and REB showed Ap at 37 and 32°C, respectively. CONCLUSIONS: Under the condition of this study, the new heat treatment technique of MT technology could enhance the fatigue fracture resistance of the reciprocating files made of M-wire and Blue-wire.


Assuntos
Temperatura Alta , Preparo de Canal Radicular , Falha de Equipamento , Estresse Mecânico , Instrumentos Odontológicos , Teste de Materiais , Desenho de Equipamento , Titânio
4.
Foot Ankle Int ; 45(5): 485-495, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38348624

RESUMO

BACKGROUND: This study examines the correction of lesser toe valgus deviation following proximal chevron metatarsal osteotomy (PCMO) and Akin osteotomy in moderate to severe hallux valgus patients, while identifying influencing factors. METHOD: Among 89 patients (116 feet), those with moderate to severe hallux valgus underwent PCMO and Akin osteotomy. Radiologic assessments included preoperative metatarsus adductus angle (MAA), hallux valgus angle (HVA), intermetatarsal angle (IMA), valgus angles of the second to fourth metatarsophalangeal joints, and hallux valgus recurrence. Assessments included visual analog scale (VAS) pain scores, American Orthopaedic Foot & Ankle Society (AOFAS) scores, and patient satisfaction over an average follow-up of 30.6 ± 21.2 (range, 12-99) months. RESULTS: The mean preoperative HVA of 34.4 degrees decreased to 8.7 degrees at final follow-up. The valgus angles of the second, third, and fourth toes improved by 37.1%, 27%, and 44.5%, respectively. In metatarsus adductus patients, lesser toe valgus angles were significantly higher both preoperatively and at final follow-up. Hallux valgus recurrence patients had higher preoperative and final follow-up IMA and valgus angles in the second and third toes. Nonrecurrence patients showed greater decreases in these angles. A larger HVA correction corresponded to a greater decrease in lesser toe valgus deviation. VAS and AOFAS scores improved significantly at the last follow-up. CONCLUSION: The study found a significant reduction in the valgus angle of the second, third, and fourth toes after PCMO and Akin osteotomy in moderate to severe hallux valgus cases, without additional surgeries on lesser toes. The lesser toe angular reductions were less pronounced in patients with metatarsus adductus or with hallux valgus recurrence. LEVEL OF EVIDENCE: Level IV, case series.


Assuntos
Hallux Valgus , Ossos do Metatarso , Osteotomia , Humanos , Hallux Valgus/cirurgia , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/fisiopatologia , Osteotomia/métodos , Ossos do Metatarso/cirurgia , Ossos do Metatarso/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Radiografia , Estudos Retrospectivos , Idoso , Satisfação do Paciente , Articulação Metatarsofalângica/cirurgia , Articulação Metatarsofalângica/fisiopatologia , Articulação Metatarsofalângica/diagnóstico por imagem , Dedos do Pé/cirurgia , Medição da Dor
5.
J Orthop Sci ; 29(2): 615-620, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36842894

RESUMO

BACKGROUND: In hallux valgus surgery, it is essential to accurately assess the position of the sesamoids both pre- and postoperatively. Weight-bearing foot anteroposterior, tangential sesamoid, and semi-weight-bearing computed tomography axial views are radiographic methods used to assess the medial sesamoid position. This study aimed to measure the medial sesamoid position and evaluate the correlation between these three radiographic methods. METHODS: This retrospective study comprised 59 feet from 49 patients who underwent hallux valgus surgery. The mean age of patients was 54.6 (range, 22-70) years. We took preoperative and postoperative measurements using the weight-bearing anteroposterior, tangential sesamoid, and semi-weight-bearing computed tomography axial views to assess the medial sesamoid position. RESULTS: The mean grades of the medial sesamoid position preoperatively and 6 months postoperatively were 2.5 and 0.8, 1.6 and 0.4, and 1.3 and 0.3 points based on the anteroposterior, tangential sesamoid, and computed tomography axial views, respectively (P < 0.001). Preoperatively, there was a strong positive correlation between the computed tomography axial and tangential sesamoid views (P < 0.001, r = 0.645) and anteroposterior and computed tomography axial views (P < 0.001, r = 0.468). In contrast, the tangential sesamoid and anteroposterior views showed a weak positive correlation (P = 0.03, r = 0.283). Six months postoperatively, there was a positive correlation between the computed tomography axial and tangential sesamoid views (P < 0.001, r = 0.473), anteroposterior and computed tomography axial views (P < 0.001, r = 0.470), and tangential sesamoid and anteroposterior views (P < 0.001, r = 0.480). CONCLUSIONS: We observed that the anteroposterior view exhibited a higher degree of medial sesamoid position displacement than the computed tomography axial and tangential sesamoid views. For the preoperative evaluation of the medial sesamoid position, the correlation between the computed tomography axial and tangential sesamoid views was stronger than that between the tangential sesamoid and anteroposterior views. However, all three views showed strong correlations postoperatively.


Assuntos
Hallux Valgus , Hallux , Ossos do Metatarso , Ossos Sesamoides , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/cirurgia , Estudos Retrospectivos , Ossos Sesamoides/diagnóstico por imagem , Ossos Sesamoides/cirurgia , Tomografia Computadorizada por Raios X , Cuidados Pré-Operatórios , Ossos do Metatarso/cirurgia
6.
Adv Sci (Weinh) ; 11(4): e2305085, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036421

RESUMO

Self-assembled materials with complex nanoscale and mesoscale architecture attract considerable attention in energy and sustainability technologies. Their high performance can be attributed to high surface area, quantum effects, and hierarchical organization. Delineation of these contributions is, however, difficult because complex materials display stochastic structural patterns combining both order and disorder, which is difficult to be consistently reproduced yet being important for materials' functionality. Their compositional variability make systematic studies even harder. Here, a model system of FeSe2 "hedgehog" particles (HPs) was selected  to gain insight into the mechanisms of charge storage n complex nanostructured materials common for batteries and supercapacitors. Specifically, HPs represent self-assembled biomimetic nanomaterials with a medium level of complexity; they display an organizational pattern of spiky colloids with considerable disorder yet non-random; this patternt is consistently reproduced from particle to particle. . It was found that HPs can accommodate ≈70× greater charge density than spheroidal nano- and microparticles. Besides expanded surface area, the enhanced charge storage capacity was enabled by improved hole transport and reversible atomic conformations of FeSe2 layers in the blade-like spikes associated with the rotatory motion of the Se atoms around Fe center. The dispersibility of HPs also enables their easy integration into energy storage devices. HPs quadruple stored electrochemical energy and double the storage modulus of structural supercapacitors.

7.
Cell Tissue Res ; 395(1): 53-62, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985496

RESUMO

Glomerular epithelial protein-1 (Glepp1), a R3 subtype family of receptor-type protein tyrosine phosphatases, plays important role in the activation of Src family kinases and regulates cellular processes such as cell proliferation, differentiation, and apoptosis. In this study, we firstly examined the functional evaluation of Glepp1 in tooth development and morphogenesis. The precise expression level and developmental function of Glepp1 were examined by RT-qPCR, in situ hybridization, and loss and gain of functional study using a range of in vitro organ cultivation methods. Expression of Glepp1 was detected in the developing tooth germs in cap and bell stage of tooth development. Knocking down Glepp1 at E13 for 2 days showed the altered expression levels of tooth development-related signaling molecules, including Bmps, Dspp, Fgf4, Lef1, and Shh. Moreover, transient knock down of Glepp1 revealed alterations in cellular physiology, examined by the localization patterns of Ki67 and E-cadherin. Similarly, knocking down of Glepp1 showed disrupted enamel rod and interrod formation in 3-week renal transplanted teeth. In addition, due to attrition of odontoblastic layers, the expression signals of Dspp and the localization of NESTIN were almost not detected after knock down of Glepp1; however, their expressions were increased after Glepp1 overexpression. Thus, our results suggested that Glepp1 plays modulating roles during odontogenesis by regulating the expression levels of signaling molecules and cellular events to achieve the proper structural formation of hard tissue matrices in mice molar development.


Assuntos
Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores , Dente , Animais , Camundongos , Regulação da Expressão Gênica no Desenvolvimento , Morfogênese , Odontogênese , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo , Transdução de Sinais , Dente/metabolismo
8.
J Endod ; 50(2): 213-219, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37924940

RESUMO

INTRODUCTION: The aim of this study was to evaluate the torsional resistance, cyclic fatigue resistance, and bending stiffness of nickel-titanium (NiTi) file systems with different heat treatments and cross-sectional designs. METHODS: WaveOne Primary treated with memory-triple (MT) heat treatment (WOMT) was compared with WaveOne Primary (WO) and WaveOne Gold Primary (WOG). Torsional resistance test was performed using a customized device, and the distortion angle, ultimate strength, and toughness were evaluated. For cyclic fatigue resistance test, the instruments were reciprocated with continuous 4 mm up-and-down movement until fracture in a customized device, and the time to fracture was compared. Fracture surfaces of each group were examined under the scanning electron microscope. Bending stiffness was measured using a custom-made device. The results were analyzed using one-way analysis of variance and the Tukey's post hoc comparison at a significance level of 95%. RESULTS: WOMT showed higher ultimate strength and toughness than the other systems (P < .05). WOMT also showed highest cyclic fatigue resistance among the tested groups (P < .05). WO had the highest bending stiffness than others, whereas WOMT had a larger residual angle than others (P < .05). CONCLUSIONS: This new MT heat treatment technique makes NiTi file more flexible and improves its mechanical properties. In addition, the effect of heat treatment on flexibility was found to be more significant than that of the cross-sectional area.


Assuntos
Ligas , Temperatura Alta , Titânio , Níquel , Instrumentos Odontológicos , Desenho de Equipamento , Preparo de Canal Radicular , Estresse Mecânico , Teste de Materiais , Torção Mecânica
9.
J Cell Physiol ; 239(1): 112-123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38149778

RESUMO

Lipid biosynthesis is recently studied its functions in a range of cellular physiology including differentiation and regeneration. However, it still remains to be elucidated in its precise function. To reveal this, we evaluated the roles of lysophosphatidic acid (LPA) signaling in alveolar bone formation using the LPA type 2 receptor (LPAR2) antagonist AMG-35 (Amgen Compound 35) using tooth loss without periodontal disease model which would be caused by trauma and usually requires a dental implant to restore masticatory function. In this study, in vitro cell culture experiments in osteoblasts and periodontal ligament fibroblasts revealed cell type-specific responses, with AMG-35 modulating osteogenic differentiation in osteoblasts in vitro. To confirm the in vivo results, we employed a mouse model of tooth loss without periodontal disease. Five to 10 days after tooth extraction, AMG-35 facilitated bone formation in the tooth root socket as measured by immunohistochemistry for differentiation markers KI67, Osteocalcin, Periostin, RUNX2, transforming growth factor beta 1 (TGF-ß1) and SMAD2/3. The increased expression and the localization of these proteins suggest that AMG-35 elicits osteoblast differentiation through TGF-ß1 and SMAD2/3 signaling. These results indicate that LPAR2/TGF-ß1/SMAD2/3 represents a new signaling pathway in alveolar bone formation and that local application of AMG-35 in traumatic tooth loss can be used to facilitate bone regeneration and healing for further clinical treatment.


Assuntos
Lisofosfolipídeos , Osteogênese , Receptores de Lisofosfolipídeos , Perda de Dente , Animais , Camundongos , Diferenciação Celular/fisiologia , Lisofosfolipídeos/metabolismo , Osteoblastos/metabolismo , Ligamento Periodontal/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Receptores de Lisofosfolipídeos/metabolismo
10.
IEEE Trans Vis Comput Graph ; 29(11): 4556-4566, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37788204

RESUMO

Redirected walking allows users to naturally locomote within virtual environments that are larger than or different in layout from the physically tracked space. In this paper, we proposed novel optimization-driven alignment-based and Artificial Potential Field (APF) redirected walking controllers, as well as an integrated version of the two. The first two controllers employ objective functions of one variable, which is the included angle between the user's heading vector and the target vector originating from the user's physical position. The optimized angle represents the physical cell that is best aligned with the virtual cell or the target vector on which the designated point has the minimum APF value. The derived optimized angle is used to finely set RDW gains. The two objective functions can be optimized simultaneously, leading to an integrated controller that is potentially able to take advantage of the alignment-based controller and APF-based controller. Through extensive simulation-based studies, we found that the proposed alignment-based and integrated controllers significantly outperform the state-of-the-art controllers and the proposed APF based controller in terms of the number of resets. Furthermore, the proposed alignment controller and integrated controller provide a more uniform likelihood distribution across distance between resets, as compared to the other controllers.

11.
Front Neurol ; 14: 1184998, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456633

RESUMO

Background: Disorders of consciousness (DOC) resulting from acquired brain injury (ABI) increase the mortality rate of patients, complicate rehabilitation, and increase the physical and economic burden that DOC imposes on patients and their families. Thus, treatment to promote early awakening from DOC is vital. Transcranial direct current stimulation (tDCS) has shown great potential for promoting neuro-electrochemical activity. However, previous tDCS studies did not consider structural damage or head and brain lesions, so the applicability of the results to all DOC patients was limited. In this study, to establish a patient-specific tDCS treatment plan considering the brain lesions of and damage sustained by DOC patients, we considered the electric field calculated by a the "finite electric" three-dimensional brain model based on magnetic resonance images. This protocol was developed to aid tDCS treatment of actual patients, and to verify its safety and effectiveness. Methods/design: Twenty-four patients with DOC after ABI will be enrolled in this cross-over trial. All participants will receive typical rehabilitation combined with sham tDCS and typical rehabilitation plus personalized tDCS (P-tDCS). Each interventional period will last 2 weeks (30 min/day, 5 days/week). The primary outcome [score on the Korean version of the Coma Recovery Scale-Revised (K-CRS-R)] will be assessed at baseline and the end of the first day of the intervention. Secondary outcomes (K-CRS-R at 1 week and 2 weeks after experimental session and quantitative EEG changes quantitative electroencephalography changes) will be measured at baseline and the end of week 4. Adverse events will be recorded during each treatment session. Discussion: For patients with neurological disorders, tDCS has served as a painless, non-invasive, easily applied, and effective therapy for several decades, and there is some evidence that it can improve the level of consciousness of patients with DOC. However, variability in the effects on consciousness among subjects have been reported and personalized strategies are lacking. This protocol is for a randomized controlled trial designed to validate the effectiveness and safety of P-tDCS combined with typical rehabilitation for DOC. Clinical trial registration: https://cris.nih.go.kr, identifier KCT0007157.

12.
Int Orthop ; 47(8): 2013-2021, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37310443

RESUMO

PURPOSE: There are controversies about combining distal tibia medial opening-wedge osteotomy (DTMO) with fibular valgization osteotomy (FVO) when performing supramalleolar osteotomy (SMO) for medial ankle osteoarthritis. This study aimed to assess the effect of FVO on the coronal translation of the mechanical axis by comparing the improvement of radiological indices after DTMO with and without FVO. METHODS: Forty-three ankles (mean follow-up: 42.0 months) were reviewed after SMO. Among them, 35/43 (81.4%) underwent DTMO with FVO, while 8/43 (18.6%) underwent DTMO only. To evaluate the effect of FVO radiologically, the medial gutter space (MGS) and talus centre migration (TCM) were measured. RESULTS: Post-operatively, MGS and TCM were not significantly different after DTMO only and DTMO with FVO. However, the improvement of MGS was significantly higher in the combined FVO group (0.8 mm (standard deviation [SD] 0.8 mm) vs. 1.5 mm (SD 0.8 mm); p = 0.015). More lateral translation of the talus was achieved in the FVO group (5.1 mm (SD 2.3 mm) vs. 7.5 mm (SD 3.0 mm); p = 0.033). However, the changes in the MGS and TCM were not significantly correlated with the clinical outcomes (p > 0.05). CONCLUSION: Our radiological evaluation confirmed a significant medial gutter space widening and lateral talar translation after the addition of FVO. The SMO with fibular osteotomy allows greater shifting of the talus and, therefore, the weight-bearing axis.


Assuntos
Tornozelo , Osteoartrite , Humanos , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Estudos Retrospectivos , Osteoartrite/diagnóstico por imagem , Osteoartrite/cirurgia , Osteotomia/efeitos adversos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
13.
Diagnostics (Basel) ; 13(11)2023 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-37296812

RESUMO

The purpose of this study was to investigate the feasibility of the fluid-attenuated inversion recovery sequence with fat suppression (FLAIR-FS) for the assessment of ankle synovitis without contrast enhancement. FLAIR-FS and contrast-enhanced, T1-weighted sequences (CE-T1) of 94 ankles were retrospectively reviewed by two radiologists. Grading of synovial visibility (four-point scale) and semi-quantitative scoring of synovial thickness (three-point scale) were performed in four compartments of the ankle in both sequences. Synovial visibility and thickness in FLAIR-FS and CE-T1 images were compared, and agreement between both sequences was assessed. Synovial visibility grades and synovial thickness scores for FLAIR-FS images were lower than those for CE-T1 images (reader 1, p = 0.016, p < 0.001; reader 2, p = 0.009, p < 0.001). Dichotomized synovial visibility grades (partial vs. full visibility) were not significantly different between both sequences. The agreement in synovial thickness scores between the FLAIR-FS and CE-T1 images was moderate to substantial (κ = 0.41-0.65). The interobserver agreement between the two readers was fair for synovial visibility (κ = 0.27-0.32) and moderate to substantial for synovial thickness (κ = 0.54-0.74). In conclusion, FLAIR-FS is a feasible MRI sequence for the evaluation of ankle synovitis without contrast enhancement.

14.
ACS Appl Mater Interfaces ; 15(27): 32707-32716, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37377389

RESUMO

Two-dimensional (2D) siloxene is attracting considerable research interest recently principally owing to its inherent compatibility with silicon-based semiconductor technology. -The synthesis of siloxene has been mostly limited to multilayered structures using traditional topochemical reaction procedures. Herein, we report high-yield synthesis of single to few-layer siloxene nanosheets by developing a two-step interlayer expansion and subsequent liquid phase exfoliation procedure. Our protocol enables high-yield production of few-layer siloxene nanosheets with a lateral dimension of up to 4 µm and thickness ranging from 0.8 to 4.8 nm, corresponding to single to a few layers, well stabilized in water. The atomically flat nature of exfoliated siloxene can be exploited for the construction of 2D/2D heterostructure membranes via typical solution processing. We demonstrate highly ordered graphene/siloxene heterostructure films with synergistic mechanical and electrical properties, which deliver noticeably high device capacitance when assembled into a coin cell symmetric supercapacitor device structures. Additionally, we demonstrate that the mechanically flexible exfoliated siloxene-graphene heterostructure enables its direct use in flexible and wearable supercapacitor applications.

15.
Small ; 19(39): e2302023, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37246275

RESUMO

Deoxyribonuclease-I (DNase-I), a representative endonuclease, is an important biomarker for the diagnosis of infectious diseases and cancer progression. However, enzymatic activity decreases rapidly ex vivo, which highlights the need for precise on-site detection of DNase-I. Here, a localized surface plasmon resonance (LSPR) biosensor that enables the simple and rapid detection of DNase-I is reported. Moreover, a novel technique named electrochemical deposition and mild thermal annealing (EDMIT) is applied to overcome signal variations. By taking advantage of the low adhesion of gold clusters on indium tin oxide substrates, both the uniformity and sphericity of gold nanoparticles are increased under mild thermal annealing conditions via coalescence and Ostwald ripening. This ultimately results in an approximately 15-fold decrease in LSPR signal variations. The linear range of the fabricated sensor is 20-1000 ng mL-1 with a limit of detection (LOD) of 127.25 pg mL-1 , as demonstrated by spectral absorbance analyses. The fabricated LSPR sensor stably measured DNase-I concentrations from samples collected from both an inflammatory bowel disease (IBD) mouse model, as well as human patients with severe COVID-19 symptoms. Therefore, the proposed LSPR sensor fabricated via the EDMIT method can be used for early diagnosis of other infectious diseases.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Animais , Camundongos , Humanos , Ressonância de Plasmônio de Superfície/métodos , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Desoxirribonucleases
16.
J Cell Physiol ; 238(7): 1520-1529, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37098720

RESUMO

To understand the mechanisms underlying tooth morphogenesis, we examined the developmental roles of important posttranslational modification, O-GlcNAcylation, which regulates protein stability and activity by the addition and removal of a single sugar (O-GlcNAc) to the serine or threonine residue of the intracellular proteins. Tissue and developmental stage-specific immunostaining results against O-GlcNAc and O-GlcNAc transferase (OGT) in developing tooth germs would suggest that O-GlcNAcylation is involved in tooth morphogenesis, particularly in the cap and secretory stage. To evaluate the developmental function of OGT-mediated O-GlcNAcylation, we employed an in vitro tooth germ culture method at E14.5, cap stage before secretory stage, for 1 and 2 days, with or without OSMI-1, a small molecule OGT inhibitor. To examine the mineralization levels and morphological changes, we performed renal capsule transplantation for one and three weeks after 2 days of in vitro culture at E14.5 with OSMI-1 treatment. After OGT inhibition, morphological and molecular alterations were examined using histology, immunohistochemistry, real-time quantitative polymerase chain reaction, in situ hybridization, scanning electron microscopy, and ground sectioning. Overall, inhibition of OGT resulted in altered cellular physiology, including proliferation, apoptosis, and epithelial rearrangements, with significant changes in the expression patterns of ß-catenin, fibroblast growth factor 4 (fgf4), and sonic hedgehog (Shh). Moreover, renal capsule transplantation and immunolocalizations of Amelogenin and Nestin results revealed that OGT-inhibited tooth germs at cap stage exhibited with structural changes in cuspal morphogenesis, amelogenesis, and dentinogenesis of the mineralized tooth. Overall, we suggest that OGT-mediated O-GlcNAcylation regulates cell signaling and physiology in primary enamel knot during tooth development, thus playing an important role in mouse molar morphogenesis.


Assuntos
N-Acetilglucosaminiltransferases , Dente , Animais , Camundongos , Apoptose/fisiologia , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional , Dente/crescimento & desenvolvimento , Dente/metabolismo
17.
Artigo em Inglês | MEDLINE | ID: mdl-37027728

RESUMO

Virtual Reality (VR) is well-known for its use in interdisciplinary applications and research. The visual representation of these applications could vary depending in their purpose and hardware limitation, and in those situations could require an accurate perception of size for task performance. However, the relationship between size perception and visual realism in VR has not yet been explored. In this contribution, we conducted an empirical evaluation using a between-subject design over four conditions of visual realism, namely Realistic, Local Lighting, Cartoon, and Sketch on size perception of target objects in the same virtual environment. Additionally, we gathered participants' size estimates in the real world via a within-subject session. We measured size perception using concurrent verbal reports and physical judgments. Our result showed that although participants' size perception was accurate in the realistic condition, surprisingly they could still tune into the invariant but meaningful information in the environment to accurately estimate the size of targets in the non-photorealistic conditions as well. We additionally found that size estimates in verbal and physical responses were generally different in real world and VR viewing and were moderated by trial presentation over time and target object widths.

18.
Libyan J Med ; 18(1): 2182683, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36855243

RESUMO

Etomidate is an anesthetic agent used in hemodynamically unstable patients, but its use has been controversial in septic patients. The response of high-mobility group box 1 (HMGB1), a late-phase lethal cytokine in sepsis, to etomidate has not been reported. This study investigated the effects of etomidate on the expression and release of HMGB1 and the underlying mechanism using a cecal ligation and puncture (CLP) model. Thirty-six male Sprague-Dawley rats were divided into sham, CLP, and Etomi groups. Sepsis was induced in the CLP and Etomi groups, and intravenous etomidate (4 mg/kg) was infused for 40 min immediately after operation in the Etomi group. Serum creatinine, alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and HMGB1 levels were measured 6 and 24 hours after surgery. Activation of nuclear factor (NF)-ĸB and HMGB1 mRNA expression in the liver, lung, kidney, and ileum tissues were measured, and immunohistochemical staining of HMGB1 was implemented. Increases of the TNF-α level 6 h after CLP and ALT and IL-6 levels 24 h after CLP were significantly inhibited by etomidate treatment. Etomidate treatment also significantly attenuated the increase in serum HMGB1 level at 6 and 24 h after CLP and suppressed the NF-ĸB and HMGB1 mRNA in multiple organs 24 h after CLP. Immunohistochemical staining also revealed that etomidate treatment inhibited HMGB1 expression. Etomidate inhibited the systemic release of HMGB1 and its expression in various organs. The mechanism may be associated with the inhibitory effects of etomidate on pro-inflammatory cytokine release and NF-ĸB activity.


Assuntos
Etomidato , Proteína HMGB1 , Sepse , Masculino , Ratos , Animais , NF-kappa B , Etomidato/farmacologia , Ratos Sprague-Dawley , Sepse/tratamento farmacológico , Citocinas , Interleucina-6
19.
Small ; 19(22): e2207966, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36861366

RESUMO

Herein, a novel combination of Mg- and Ga-co-doped ZnO (MGZO)/Li-doped graphene oxide (LGO) transparent electrode (TE)/electron-transporting layer (ETL) has been applied for the first time in Cu2 ZnSn(S,Se)4 (CZTSSe) thin-film solar cells (TFSCs). MGZO has a wide optical spectrum with high transmittance compared to that with conventional Al-doped ZnO (AZO), enabling additional photon harvesting, and has a low electrical resistance that increases electron collection rate. These excellent optoelectronic properties significantly improved the short-circuit current density and fill factor of the TFSCs. Additionally, the solution-processable alternative LGO ETL prevented plasma-induced damage to chemical bath deposited cadmium sulfide (CdS) buffer, thereby enabling the maintenance of high-quality junctions using a thin CdS buffer layer (≈30 nm). Interfacial engineering with LGO improved the Voc of the CZTSSe TFSCs from 466 to 502 mV. Furthermore, the tunable work function obtained through Li doping generated a more favorable band offset in CdS/LGO/MGZO interfaces, thereby, improving the electron collection. The MGZO/LGO TE/ETL combination achieved a power conversion efficiency of 10.67%, which is considerably higher than that of conventional AZO/intrinsic ZnO (8.33%).

20.
Sci Rep ; 13(1): 3220, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828940

RESUMO

Low dose and accessibility have increased the application of cone beam computed tomography (CBCT). Often serial images are captured for patients to diagnose and plan treatment in the craniofacial region. However, CBCT images are highly variable and lack harmonious reproduction, especially in the head's orientation. Though user-defined orientation methods have been suggested, the reproducibility remains controversial. Here, we propose a landmark-free reorientation methodology based on principal component analysis (PCA) for harmonious orientation of serially captured CBCTs. We analyzed three serial CBCT scans collected for 29 individuals who underwent orthognathic surgery. We first defined a region of interest with the proposed protocol by combining 2D rendering and 3D convex hull method, and identified an intermediary arrangement point. PCA identified the y-axis (anterioposterior) followed by the secondary x-axis (transverse). Finally, by defining the perpendicular z-axis, a new global orientation was assigned. The goodness of alignment (Hausdorff distance) showed a marked improvement (> 50%). Furthermore, we clustered cases based on clinical asymmetry and validated that the protocol was unaffected by the severity of the skeletal deformity. Therefore, it could be suggested that integrating the proposed algorithm as the preliminary step in CBCT evaluation will address a fundamental step towards harmonizing the craniofacial imaging records.


Assuntos
Ossos Faciais , Imageamento Tridimensional , Humanos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes , Postura , Tomografia Computadorizada de Feixe Cônico/métodos
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