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Chlorophyll degradation and carotenoid biosynthesis, which occur almost simultaneously during fruit ripening, are essential for the coloration and nutritional value of fruits. However, the synergistic regulation of these 2 processes at the transcriptional level remains largely unknown. In this study, we identified a WRKY transcription factor, CrWRKY42, from the transcriptome data of the yellowish bud mutant "Jinlegan" ([Citrus unshiu × C. sinensis] × C. reticulata) tangor and its wild-type "Shiranui" tangor, which was involved in the transcriptional regulation of both chlorophyll degradation and carotenoid biosynthesis pathways. CrWRKY42 directly bound to the promoter of ß-carotene hydroxylase 1 (CrBCH1) and activated its expression. The overexpression and interference of CrWRKY42 in citrus calli demonstrated that CrWRKY42 promoted carotenoid accumulation by inducing the expression of multiple carotenoid biosynthetic genes. Further assays confirmed that CrWRKY42 also directly bound to and activated the promoters of the genes involved in carotenoid biosynthesis, including phytoene desaturase (CrPDS) and lycopene ß-cyclase 2 (CrLCYB2). In addition, CrWRKY42 could bind to the promoters of NONYELLOW COLORING (CrNYC) and STAY-GREEN (CrSGR) and activate their expression, thus promoting chlorophyll degradation. The overexpression and silencing of CrWRKY42 in citrus fruits indicated that CrWRKY42 positively regulated chlorophyll degradation and carotenoid biosynthesis by synergistically activating the expression of genes involved in both pathways. Our data revealed that CrWRKY42 acts as a positive regulator of chlorophyll degradation and carotenoid biosynthesis to alter the conversion of citrus fruit color. Our findings provide insight into the complex transcriptional regulation of chlorophyll and carotenoid metabolism during fruit ripening.
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Carotenoides , Clorofila , Citrus , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fatores de Transcrição , Carotenoides/metabolismo , Citrus/genética , Citrus/metabolismo , Clorofila/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Frutas/genética , Frutas/metabolismo , Frutas/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genéticaRESUMO
Chemodynamic therapy based on the Fenton reaction has been developed as an extremely promising modality for cancer therapeutics. In this study, a core-shell structure nanoplatform was constructed by a Au nanorod externally encapsulating Ce/Zn-based composites (ACZO). The nanoparticles can catalyze the generation of reactive oxygen species (ROS) under acidic conditions and effectively consume existing glutathione (GSH) to destroy the redox balance within the tumor. Moreover, the decomposition of the nanocomplexes under acidic conditions releases large amounts of zinc ions, leading to zinc overload in cancer cells. The photothermal effect generated by the Au nanorods not only provides photothermal therapy (PTT) but also augments the catalytic reaction and ions action mentioned above. This facile strategy to improve the efficacy of chemodynamic therapy by the photothermal enhancement of catalytic activity and zinc ion release provides a promising perspective for potential tumor treatment.
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Nanopartículas , Nanotubos , Neoplasias , Humanos , Catálise , Glutationa , Zinco/farmacologia , Íons , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Peróxido de Hidrogênio , Microambiente TumoralRESUMO
Teaching gesture recognition is a technique used to recognize the hand movements of teachers in classroom teaching scenarios. This technology is widely used in education, including for classroom teaching evaluation, enhancing online teaching, and assisting special education. However, current research on gesture recognition in teaching mainly focuses on detecting the static gestures of individual students and analyzing their classroom behavior. To analyze the teacher's gestures and mitigate the difficulty of single-target dynamic gesture recognition in multi-person teaching scenarios, this paper proposes skeleton-based teaching gesture recognition (ST-TGR), which learns through spatio-temporal representation. This method mainly uses the human pose estimation technique RTMPose to extract the coordinates of the keypoints of the teacher's skeleton and then inputs the recognized sequence of the teacher's skeleton into the MoGRU action recognition network for classifying gesture actions. The MoGRU action recognition module mainly learns the spatio-temporal representation of target actions by stacking a multi-scale bidirectional gated recurrent unit (BiGRU) and using improved attention mechanism modules. To validate the generalization of the action recognition network model, we conducted comparative experiments on datasets including NTU RGB+D 60, UT-Kinect Action3D, SBU Kinect Interaction, and Florence 3D. The results indicate that, compared with most existing baseline models, the model proposed in this article exhibits better performance in recognition accuracy and speed.
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Gestos , Humanos , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , EnsinoRESUMO
In spite of the fact that remarkable developments are achieved in the design and development of novel nanocatalysts for H2 release upon dimethylamineborane hydrolysis, the development of an "on-off" switch for demand-based H2 evolution upon dimethylamineborane hydrolysis is still a matter of supreme importance, however. Herein, we synthesized a string of MoS2 nanosheet-supported RuNi bimetallic nanohybrids (RuxNi1-x/MoS2), by fixation of RuNi nanoparticles at the MoS2 surface, for the H2 evolution upon the hydrolysis of dimethylamineborane at 30 °C. For safely and effectively generating, transporting, and storing H2 gas, the selective "on-off" switch for on-demand H2 evolution upon dimethylamineborane hydrolysis over the Ru0.8Ni0.2/MoS2 nanohybrid has been successfully realized by the Zn2+/EDTA-2Na system. In particular, the H2 evolution is totally switched off by adding Zn(NO3)2. It seems that Zn2+ ions are attached and anchored at the Ru0.8Ni0.2/MoS2 surface, inhibiting their surface-active sites, leading to the termination of H2 evolution. Then, the H2 generation is subsequently reactivated by adding the EDTA-2Na solution because of its excellent coordination ability with Zn2+ ions. This study not only offers a new and efficient RuNi nanocatalyst for dimethylamineborane hydrolysis but also proposes a new method for the demand-based H2 production.
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Background: Oral lichen planus (OLP) is an infrequent autoimmune disease of the oral mucosa, which affects up to 2% of the world population. An investigation of Tripterygium wilfordii's mechanism of action for treating OLP was conducted, and a theoretical basis was provided for improving current treatment regimens. Materials and Methods: We used a network pharmacological approach to gain insight into the molecular mechanism of Tripterygium wilfordii in the treatment of OLP. Then, potential protein targets between Tripterygium wilfordii and OLP were analyzed through a drug-target network. This was followed by KEGG enrichment analysis and Gene Ontology (GO) classification. Finally, for molecular docking, AutoDock Vina was used. Results: A protein-protein interaction (PPI) network was constructed by analyzing the common targets of a total of 51 wilfordii-OLP interactions from different databases. The GO and KEGG enrichment analyses showed that the treatment of OLP with Tripterygium wilfordii mainly involves lipopolysaccharide response, bacterial molecular response, positive regulation of cytokine production, and leukocyte proliferation, and the signaling pathways mainly include the AGE-RAGE, NF-κB, Toll-like receptor, IL-17, HIF-1, and TNF signaling pathways. The molecular docking results showed that ß-sitosterol, kaempferol, hederagenin, and triptolide have a higher affinity for AKT1, TNF, CASP3, and PTGS2, respectively. Based on the CytoNCA analysis of common targets, 19 key targets, including AKT1, TNF, VEGFA, STAT3, CXCL8, PTGS2, TP53, and CASP3, and their connections were identified. Conclusions: Preliminarily, this study reveals that Tripterygium wilfordii interferes with OLP by interacting with multiple targets through multiple accesses, as validated by molecular docking.
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Líquen Plano Bucal , Tripterygium , Humanos , Simulação de Acoplamento Molecular , Caspase 3 , Farmacologia em Rede , Ciclo-Oxigenase 2 , Líquen Plano Bucal/tratamento farmacológicoRESUMO
Most existing wall-climbing robots have a fixed range of load capacity and a step distance that is small and mostly immutable. It is therefore difficult for them to adapt to a discontinuous wall with particularly large gaps. Based on a modular design and inspired by leech peristalsis and internal soft-bone connection, a bionic crawling modular wall-climbing robot is proposed in this paper. The robot demonstrates the ability to handle variable load characteristics by carrying different numbers of modules. Multiple motion modules are coupled with the internal soft bone so that they work together, giving the robot variable-step-distance functionality. This paper establishes the robotic kinematics model, presents the finite element simulation analysis of the model, and introduces the design of the multi-module cooperative-motion method. Our experiments show that the advantage of variable step distance allows the robot not only to quickly climb and turn on walls, but also to cross discontinuous walls. The maximum climbing step distance of the robot can reach 3.6 times the length of the module and can span a discontinuous wall with a space of 150 mm; the load capacity increases with the number of modules in series. The maximum load that N modules can carry is about 1.3 times the self-weight.
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Robótica , Fenômenos Biomecânicos , Biônica , Desenho de Equipamento , Movimento (Física)RESUMO
The field-of-view (FOV) of compound eyes is an important index for performance evaluation. Most artificial compound eyes are optical, fabricated by imitating insect compound eyes with a fixed FOV that is difficult to adjust over a wide range. The compound eye is of great significance in the field of tracking high-speed moving objects. However, the tracking ability of a compound eye is often limited by its own FOV size and the reaction speed of the rudder unit matched with the compound eye, so that the compound eye cannot better adapt to tracking high-speed moving objects. Inspired by the eyes of many organisms, we propose a soft-array, surface-changing compound eye (SASCE). Taking soft aerodynamic models (SAM) as the carrier and an infrared sensor as the load, the basic model of the variable structure infrared compound eye (VSICE) is established using an array of infrared sensors on the carrier. The VSICE model is driven by air pressure to change the array surface of the infrared sensor. Then, the spatial position of each sensor and its viewing area are changed and, finally, the FOV of the compound eye is changed. Simultaneously, to validate the theory, we measured the air pressure, spatial sensor position, and the FOV of the compound eye. When compared with the current compound eye, the proposed one has a wider adjustable FOV.
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As an important part of the quadruped robot, the leg determines its performance. Flexible legs or flexible joints aid in the buffering and adaptability of robots. At present, most flexible quadruped robots only have two-dimensional flexibility or use complex parallel structures to achieve three-dimensional flexibility. This research will propose a new type of three-dimensional flexible structure. This passive compliant three-dimensional flexibility reduces the weight and complex structure of the robot. The anti-impact performance of the robot is verified by a side impact experiment. The simulation and experiments show that the robot still has good stability even under a simple algorithm and that the flexible leg can reduce the impact on the quadruped robot and improve the environmental adaptability of the robot.
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Robótica , Algoritmos , Simulação por Computador , MarchaRESUMO
Heteroepitaxial structures based on Bi2Te3-type topological insulators (TIs) exhibit exotic quantum phenomena. For optimal characterization of these phenomena, it is desirable to control the interface structure during film growth on such TIs. In this process, adatom mobility is a key factor. We demonstrate that Pb mobility on the Bi2Te3(111) surface can be modified by the engineering local strain, ε, which is induced around the point-like defects intrinsically forming in the Bi2Te3(111) thin film grown on a Si(111)-7 × 7 substrate. Scanning tunneling microscopy observations of Pb adatom and cluster distributions and first-principles density functional theory (DFT) analyses of the adsorption energy and diffusion barrier Ed of Pb adatom on Bi2Te3(111) surface show a significant influence of ε. Surprisingly, Ed reveals a cusp-like dependence on ε due to a bifurcation in the position of the stable adsorption site at the critical tensile strain εc ≈ 0.8%. This constitutes a very different strain-dependence of diffusivity from all previous studies focusing on conventional metal or semiconductor surfaces. Kinetic Monte Carlo simulations of Pb deposition, diffusion, and irreversible aggregation incorporating the DFT results reveal adatom and cluster distributions compatible with our experimental observations.
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We report an atomic-scale characterization of ZrTe_{5} by using scanning tunneling microscopy. We observe a bulk band gap of â¼80 meV with topological edge states at the step edge and, thus, demonstrate that ZrTe_{5} is a two-dimensional topological insulator. We also find that an applied magnetic field induces an energetic splitting of the topological edge states, which can be attributed to a strong link between the topological edge states and bulk topology. The relatively large band gap makes ZrTe_{5} a potential candidate for future fundamental studies and device applications.
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Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, with approximately 600,000 new cases each year. A small number of HNSCCs are caused by human papillomavirus (HPV) infection. Frizzled related protein (FRZB) has been reported in many inflammatory diseases and cancers, but it is yet unclear how FRZB affects HNSCC, as well as its role and underlying mechanism. TIMER2 database was utilized to evaluate FRZB expression in cancer tissues, and FRZB expression in HNSCC tissues was confirmed by samples obtained from Gene Expression Omnibus. To identify whether FRZB could be used as a prognostic predictor, we performed univariate and multivariate Cox regression analyses. FRZB co-expression profile was explored using the LinkedOmics database, then Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analyses were performed for these FRZB-related genes in HNSCC samples. Lasso regression analysis was subsequently used to screen for prognostic variables, and we determined the infiltration of immune cells in HNSCC patients to clarify the influence of FRZB on tumor immune microenvironment. At last, we assessed the association between FRZB expression and immune checkpoint gene, and compared the sensitivity of common chemotherapeutic agents. In this study, we found that FRZB was dysregulated in HNSCC tumor tissues and had a relationship with clinical parameters. The reliability and independence of FRZB as a factor in determining a patient's prognosis for HNSCC was also established. Additional investigation revealed that FRZB was linked to common immune checkpoint genes and may be implicated in immune infiltration.
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Biomarcadores Tumorais , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Neoplasias de Cabeça e Pescoço/genética , Masculino , Feminino , Regulação Neoplásica da Expressão Gênica , Microambiente Tumoral , Pessoa de Meia-IdadeRESUMO
Ameloblastoma (AB) is a common odontogenic tumor that develops in the mouth. Despite its benign nature, AB exhibits significant invasiveness leading to tumor metastasis and high postoperative recurrence rates. Studies have shown a relationship between the occurrence and development of various tumors and non-coding RNA (ncRNA). NcRNA, transcribed from the genomes of mammals and other complex organisms, are often products of alternative splicing and processing into smaller products. MicroRNA (miRNA), circular RNA (circRNA), and long non-coding RNA (lncRNA) are the main types of ncRNA. NcRNA play increasingly significant roles in the pathogenesis of human cancers, regulating their occurrence and progression as oncogenes or tumor suppressors. They are involved in tumor development and progression through alternative splicing of pre-mRNA, transcriptional regulation, mRNA stability, protein translation, and chromatin remodeling and modification. The importance of ncRNA in AB has received significant attention in recent years. However, the biological functions and mechanisms of ncRNA in AB remain largely unknown. In this review, we not only explore the functions and roles of ncRNA in AB, but also describe and envision their potential functional roles as biomarkers in AB diagnosis. In particular, we highlight the potential of miR-29a as a molecular marker for diagnosis and therapy. As promising novel therapeutic targets, the biological functions of ncRNA need further study, which is indispensable.
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Critical-size bone defects are a common and intractable clinical problem that typically requires filling in with surgical implants to facilitate bone regeneration. Considering the limitations of autologous bone and allogeneic bone in clinical applications, such as secondary damage or immunogenicity, injectable microhydrogels with osteogenic and angiogenic effects have received considerable attention. Herein, polydopamine (PDA)-functionalized strontium alginate/nanohydroxyapatite (Sr-Alg/nHA) composite microhydrogels loaded with vascular endothelial growth factor (VEGF) were prepared using microfluidic technology. This composite microhydrogel released strontium ions stably for at least 42 days to promote bone formation. The PDA coating can release VEGF in a controlled manner, effectively promote angiogenesis around bone defects, and provide nutritional support for new bone formation. In in vitro experiments, the composite microhydrogels had good biocompatibility. The PDA coating greatly improves cell adhesion on the composite microhydrogel and provides good controlled release of VEGF. Therefore, this composite microhydrogel effectively promotes osteogenic differentiation and vascularization. In in vivo experiments, composite microhydrogels were injected into critical-size bone defects in the skull of rats, and they were shown by microcomputed tomography and tissue sections to be effective in promoting bone regeneration. These findings demonstrated that this novel microhydrogel effectively promotes bone formation and angiogenesis at the site of bone defects.
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Indóis , Osteogênese , Polímeros , Fator A de Crescimento do Endotélio Vascular , Ratos , Animais , Fator A de Crescimento do Endotélio Vascular/farmacologia , Alginatos/farmacologia , Microtomografia por Raio-X , Angiogênese , Regeneração Óssea , Crânio , Hidroxiapatitas/farmacologia , Estrôncio/farmacologiaRESUMO
Forming deep feature embeddings is an effective method for few-shot learning (FSL). However, in the case of insufficient samples, overcoming the task complexity while improving the accuracy is still a major challenge. To address this problem, this article considers the consistency between similar data from the fractal perspective, introduces a priori knowledge, and proposes a fractal embedding model by combining FSL with fractal dimension theory for the first time. We improve the original fractal dimension algorithm used to describe image texture roughness to suit a neural network. Moreover, in accordance with the improved algorithm, prior knowledge of the quantized image is integrated into the features to reduce the impact of the data distribution on the model. Experimental results obtained on multiple image benchmark datasets show that the performance of the proposed model exceeds or matches that of previous state-of-the-art models. In addition, the proposed model achieves the best performance in cross-domain scenarios, further illustrating its robustness.
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Oxidative stress (OS) is a pathological status that occurs when the body's balance between oxidants and antioxidant defense systems is broken, which can promote the development of many diseases. Nrf2, a redox-sensitive transcription encoded by NFE2L2, is the master regulator of phase II antioxidant enzymes and cytoprotective genes. In this context, Nrf2/ARE signaling can be a compelling target against OS-induced diseases. Recently, natural Nrf2/ARE regulators like dietary flavones have shown therapeutic potential in various acute and chronic diseases such as diabetes, neurodegenerative diseases, ischemia-reperfusion injury, and cancer. In this review, we aim to summarize nrf2-mediated protective effects of flavones in different conditions. Firstly, we retrospected the mechanisms of how flavones regulate the Nrf2/ARE pathway and introduced the mediator role Nrf2 plays in inflammation and apoptosis. Then we review the evidence that flavones modulated Nrf2/ARE pathway to prevent diseases in experimental models. Based on these literature, we found that flavones could regulate Nrf2 expression by mechanisms below: 1) dissociating the binding between Nrf2 and Keap1 via PKC-mediated Nrf2 phosphorylation and P62-mediated Keap1 autophagic degradation; 2) regulating Nrf2 nuclear translocation by various kinases like AMPK, MAPKs, Fyn; 3) decreasing Nrf2 ubiquitination and degradation via activating sirt1 and PI3K/AKT-mediated GSK3 inhibition; and 4) epigenetic alternation of Nrf2 such as demethylation at the promoter region and histone acetylation. In conclusion, flavones targeting Nrf2 can be promising therapeutic agents for various OS-related disorders. However, there is a lack of investigations on human subjects, and new drug delivery systems to improve flavones' treatment efficiency still need to be developed.
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The symptoms of Behçet's disease (BD), a multisystemic condition with autoimmune and inflammation as hallmarks, include arthritis, recurring oral and vaginal ulcers, skin rashes and lesions, and involvement of the nervous, gastrointestinal, and vascular systems. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), may be important regulators of inflammation and autoimmune disease. These ncRNAs are essential to the physiological and pathophysiological disease course, and miRNA in particular has received significant attention for its role and function in BD and its potential use as a diagnostic biomarker in recent years. Although promising as therapeutic targets, miRNAs must be studied further to fully comprehend how miRNAs in BD act biologically.
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Doenças Autoimunes , Síndrome de Behçet , MicroRNAs , RNA Longo não Codificante , Feminino , Humanos , MicroRNAs/genética , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/genética , Inflamação , RNA Longo não Codificante/genéticaRESUMO
BACKGROUND: As a nucleolar protein associated with ribosome biogenesis in multiple cancer types, PES1 has been reported to be overexpressed, promoting cancer cell proliferation and invasion. However, in head and neck squamous cell carcinoma (HNSCC), the role of PES1 on the prognosis and immune infiltration remains unknown. METHODS: Multiple databases and qRT-PCR evaluated the expression of PES1 in HNSCC. The prognostic potential of PES1 in HNSCC patients was analyzed by Cox regression and Kaplan-Meier curves. Then, we used LASSO regression and stepwise multivariate Cox regression to construct the PES1-related risk assessment model. In addition, the association between PES1 and tumor immune microenvironment and drug sensitivity was explored by R packages. Finally, we used cell function assays to explore in HNSCC if PES1 influences tumor growth and metastasis. RESULTS: PES1 was significantly up-regulated in HNSCC and closely correlated with HPV status, tumor stage, clinical grade, and TP53 mutation status. Survival analysis suggested that PES1 is associated with worse survival outcomes, acting as an independent prognostic indicator for HNSCC. Our model also performed well in terms of prognosis prediction. Furthermore, tumor-infiltrating immune cells and antitumor drug susceptibility were negatively related to PES1 expression. Functionally, as for HNSCC cell lines in vitro, the knockdown of PES1 could inhibit proliferation, migration, and invasion. CONCLUSION: We have demonstrated that PES1 may be a promoter of tumor growth. PES1 holds excellent promise as a novel biomarker to assess the prognosis of patients with HNSCC and may guide immunotherapy.
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Neoplasias de Cabeça e Pescoço , Microambiente Tumoral , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Microambiente Tumoral/genética , Biomarcadores , Proliferação de Células , Neoplasias de Cabeça e Pescoço/genética , Prognóstico , Proteínas de Ligação a RNARESUMO
OBJECTIVES: This study aims to evaluate the color stability and related properties including water sorption and solubility of ten light-cured composite resins in different solutions. METHODS: A total of 10 composite resins were Beautifilâ ¡(B2) and Ceram. X One Universal (CXU), Charisma (CS), Charisma Diamond (CD), Denfil (DF), DX. Universal (DXU), Filtek Z250 (Z250), Filtek Z350 XT (Z350), FS-1 (FS), and Magnafill Putty (MP). Meanwhile, a total of 20 disk-shaped samples were fabricated and randomly divided into four groups (n=5), which were immersed in distilled water (control group), curry, coffee, and red wine for 28 days. The color (CIE L∗a∗b∗) was measured by a spectrophotometer at baseline and 1, 7, 14, 21, and 28 days after immersion, and the color differences were calculated. Water sorption and solubility values were measured ba-sed on ISO 4049: 2019. In addition, three-way ANOVA was used to evaluate the influence of resin materials, solutions, and immersion time on discoloration results, meanwhile, one-way ANOVA was used to compare the water sorption values and solubility values of different materials. RESULTS: All samples showed a certain degree of color change with time. Color differences were significantly influenced by materials, solutions, and immersion time (P<0.001). The color changes of the measured materials at any time point: curry>red wine>coffee>distilled water. Thus, all materials showed clinically unacceptable discoloration (ΔE>3.3) after immersing in staining curry, coffee, and red wine for 7 days. Therefore, when immersed in curry for 28 days, CS and DXU had the smallest and the largest color difference. In addition, when immersed in coffee for 28 days, FS showed the smallest color change and DXU showed the largest. Moreover, when immersed in red wine for 28 days, FS showed the smallest color change and Z350 showed the largest. Furthermore, MP and CXU had small color differences in all solutions. Meanwhile, Z350 had the highest water sorption and MP had the lowest. The solubility values of CS and CD were significantly higher than those of other materials. CONCLUSIONS: The color stability of light-cured composite resin is materials-depended and affected by pigment types and immersion time. Thus, MP and CXU have better color stability. MP has low water sorption.
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Café , Água , Cor , Resinas Compostas , Materiais Dentários , Teste de Materiais , Solubilidade , Espectrofotometria , Propriedades de SuperfícieRESUMO
The incidence of cholecystitis is relatively high in developed countries and may usually be attributed to gallstones, the treatment for which involves complete surgical removal of the gallbladder (cholecystectomy). Bile acids produced following cholecystectomy continue to flow into the duodenum but are poorly absorbed by the colon. Excessive bile acids in the colon stimulate mucosal secretion of water and electrolytes leading, in severe cases, to diarrhoea. Bile acid diarrhoea (BAD) is difficult to diagnose, requiring a comprehensive medical history and physical examination in combination with laboratory evaluation. The current work reviews the diagnosis and treatment of BAD following cholecystectomy.
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This study aims to assess the color stability, water sorption, and solubility of 11 resin composites as commercially available dental products. Twenty samples (10 mm in diameter and 2 mm in thickness) of each material were fabricated using a customized silicone mold, followed by immersion in each of curry, coffee, wine, and distilled water for 28 days (n = 5). Baseline shade and color changes (ΔE) were measured using a reflection spectrophotometer. The CIE L*, a*, b* system was used to evaluate the color changes. Five samples of each resin composite were applied to test water sorption and solubility according to ISO 4049:2009. As a result, the ∆E values were significantly influenced by each of the three factors (composition of material, solution, time) and the interactions between them (p < 0.001). Highest resistance to discoloration was achieved by Ceram.X One Universal (CXU), followed by Magnafill Putty (MP). Generally, microhybrid composites showed fewer color changes than nanohybrid composites and giomers. DX. Universal and Filtek Z350 XT showed the highest ΔE values in all colorants. All materials tested in this study fulfilled the criteria of ISO 4049:2009; CXU and MP had the lowest water sorption and solubility. The Pearson test showed statistically significant positive correlations between water sorption and ΔE and between solubility and ΔE.