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The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.
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Aminoacil-tRNA Sintetases/metabolismo , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Viroses/imunologia , Viroses/metabolismo , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Animais , Antivirais/farmacologia , Modelos Animais de Doenças , Imunidade Inata , Camundongos , Camundongos Knockout , Peptídeos/farmacologia , Fosforilação , Ligação Proteica , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/metabolismo , Infecções por Vírus de RNA/virologia , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/imunologia , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Ubiquitinação , Viroses/virologia , Replicação ViralRESUMO
Efficient magnetic control of electronic conduction is at the heart of spintronic functionality for memory and logic applications1,2. Magnets with topological band crossings serve as a good material platform for such control, because their topological band degeneracy can be readily tuned by spin configurations, dramatically modulating electronic conduction3-10. Here we propose that the topological nodal-line degeneracy of spin-polarized bands in magnetic semiconductors induces an extremely large angular response of magnetotransport. Taking a layered ferrimagnet, Mn3Si2Te6, and its derived compounds as a model system, we show that the topological band degeneracy, driven by chiral molecular orbital states, is lifted depending on spin orientation, which leads to a metal-insulator transition in the same ferrimagnetic phase. The resulting variation of angular magnetoresistance with rotating magnetization exceeds a trillion per cent per radian, which we call colossal angular magnetoresistance. Our findings demonstrate that magnetic nodal-line semiconductors are a promising platform for realizing extremely sensitive spin- and orbital-dependent functionalities.
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An exciton is the bosonic quasiparticle of electron-hole pairs bound by the Coulomb interaction1. Bose-Einstein condensation of this exciton state has long been the subject of speculation in various model systems2,3, and examples have been found more recently in optical lattices and two-dimensional materials4-9. Unlike these conventional excitons formed from extended Bloch states4-9, excitonic bound states from intrinsically many-body localized states are rare. Here we show that a spin-orbit-entangled exciton state appears below the Néel temperature of 150 kelvin in NiPS3, an antiferromagnetic van der Waals material. It arises intrinsically from the archetypal many-body states of the Zhang-Rice singlet10,11, and reaches a coherent state assisted by the antiferromagnetic order. Using configuration-interaction theory, we determine the origin of the coherent excitonic excitation to be a transition from a Zhang-Rice triplet to a Zhang-Rice singlet. We combine three spectroscopic tools-resonant inelastic X-ray scattering, photoluminescence and optical absorption-to characterize the exciton and to demonstrate an extremely narrow excitonic linewidth below 50 kelvin. The discovery of the spin-orbit-entangled exciton in antiferromagnetic NiPS3 introduces van der Waals magnets as a platform to study coherent many-body excitons.
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NF-κB essential modulator (NEMO) is a key regulatory protein that functions during NF-κB- and interferon-mediated signaling in response to extracellular stimuli and pathogen infections. Tight regulation of NEMO is essential for host innate immune responses and for maintenance of homeostasis. Here, we report that the E3 ligase MARCH2 is a novel negative regulator of NEMO-mediated signaling upon bacterial or viral infection. MARCH2 interacted directly with NEMO during the late phase of infection and catalyzed K-48-linked ubiquitination of Lys326 on NEMO, which resulted in its degradation. Deletion of MARCH2 resulted in marked resistance to bacterial/viral infection, along with increased innate immune responses both in vitro and in vivo. In addition, MARCH2-/- mice were more susceptible to LPS challenge due to massive production of cytokines. Taken together, these findings provide new insight into the molecular regulation of NEMO and suggest an important role for MARCH2 in homeostatic control of innate immune responses.
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Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismo , Animais , Linhagem Celular , Feminino , Deleção de Genes , Humanos , Imunidade Inata/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , NF-kappa B/metabolismo , Transdução de Sinais/genética , Transcriptoma , Ubiquitina-Proteína Ligases/genética , UbiquitinaçãoRESUMO
OBJECTIVE: This study aimed to examine whether the intraoperative use of Lugol's solution reduces the proportion of positive resection margins (RMs) using the data of women who underwent large loop excision of the transformation zone (LLETZ). MATERIALS AND METHODS: A total of 1,751 consecutive women with cervical intraepithelial neoplasia (CIN) who underwent LLETZ with or without Lugol's solution were retrospectively retrieved from each database of 3 university hospitals in South Korea. Outcomes included positive RMs and residual disease pathologically confirmed within 6 months after LLETZ. RESULTS: Positive RMs were noted in 345 cases (19.7%). Among 1,507 women followed up, residual disease was diagnosed in 100 cases (6.6%) (69/308 cases with positive RMs; 31/1,199 cases with negative RMs). The Lugol's solution group was less likely to have positive RMs (11.8% vs 25.5%, p < .01), to require additional surgical intervention (5.4% vs 10.2%, p < .01), and to have residual disease (4.9% vs 8.0%, p = .02). On multiple logistic regression analysis, Lugol's solution reduced the proportion of positive RMs (adjusted odds ratio [aOR], 0.31). Age (50 years or older; aOR, 1.64), preconization cervical cytology (aOR, 1.53), high-risk human papillomavirus (aOR, 1.75), and CIN 2 or 3 (aOR, 2.65) were independent risk factors for margin positivity ( p < .01 for all except high-risk human papillomavirus of p = .05). CONCLUSIONS: Lugol's solution optimizes CIN treatment by reducing the proportion of positive RMs and residual disease after LLETZ.
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Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/diagnóstico , Estudos Retrospectivos , Margens de Excisão , Neoplasia Residual/cirurgiaRESUMO
The unique discovery of the magnetic exciton in van der Waals antiferromagnet NiPS3 arises between two quantum many-body states of a Zhang-Rice singlet excited state and a Zhang-Rice triplet ground state. Simultaneously, the spectral width of photoluminescence originating from this exciton is exceedingly narrow as 0.4 meV. These extraordinary properties, including the extreme coherence of the magnetic exciton in NiPS3, beg many questions. We studied doping effects using Ni1-xCdxPS3 using two experimental techniques and theoretical studies. Our experimental results show that the magnetic exciton is drastically suppressed upon a few % Cd doping. All this happens while the width of the exciton only gradually increases and the antiferromagnetic ground state is robust. These results highlight the lattice uniformity's hidden importance as a prerequisite for coherent magnetic exciton. Finally, an exciting scenario emerges: the broken charge transfer forbids the otherwise uniform formation of the coherent magnetic exciton in (Ni,Cd)PS3.
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The purpose of this study was to investigate the initiation of autophagy activation and apoptosis in nucleus pulposus cells under temporary compression (TC) and sustained compression (SC) to identify ideal research approaches in intervertebral disc degeneration. Various techniques were used: radiography (X-ray), magnetic resonance imaging (MRI), transmission electron microscope (TEM), H&E staining, Masson's trichrome staining, immunohistochemistry (IHC) (LC3, beclin-1, and cleaved caspase-3), and real-time polymerase chain reaction (RT-qPCR) for autophagy-related (beclin-1, LC3, and P62) and apoptosis-related (caspase-3 and PARP) gene expression analysis. X-ray and MRI revealed varying degrees of disc degeneration, ranging from moderate to severe in both groups. The severity was directly linked to compression duration, with SC resulting in notably severe central NP cell degeneration. Surprisingly, TC also caused similar, though less severe, degeneration. Elevated expression of LC3 and beclin-1 was identified after 6 weeks, but it notably declined after 12 weeks. Central NP cells in both groups exhibited increased expression of cleaved caspase-3 that was positively correlated with the duration of SC. TC showed fewer apoptotic markers compared to SC. LC3, beclin-1, and P62 mRNA expression peaked after 6 weeks and declined after 12 weeks in both groups. Cleaved caspase-3 and PARP expression peaked in SC, positively correlating with longer compression duration, while TC showed lower levels of apoptosis gene expression. Furthermore, TEM results revealed different events of the autophagic degradation process after 2 weeks of compression. TCmay be ideal for studying early triggered autophagy-mediated degeneration, while SC may be ideal for studying late or slower-triggered apoptosis-mediated degeneration.
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Degeneração do Disco Intervertebral , Humanos , Degeneração do Disco Intervertebral/metabolismo , Caspase 3/genética , Proteína Beclina-1/genética , Proteína Beclina-1/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Apoptose , AutofagiaRESUMO
BACKGROUND: Malignant ascites contributes to the metastatic process by facilitating the multifocal dissemination of ovarian tumour cells onto the peritoneal surface. However, the prognostic and diagnostic relevance of ascitic fluid remains largely unknown. Herein, we investigated the potential clinical value and therapeutic utility of ascitic autotaxin (ATX) in epithelial ovarian cancer (EOC). METHODS: ATX expression was assessed in clinical samples. Spheroid-forming assay, real-time PCR, western blot analysis, invadopodia assay, and adhesion assays were performed. RESULTS: Ascitic ATX expression was highly elevated in patients with ovarian cancer compared to those with benign ascites and was associated with advanced stage, high grade, and a short disease-free period in patients with EOC. Combining the diagnostic ability of ascitic ATX and serum CA-125 levels significantly improved the area under the curve (AUC) value for EOC compared to serum CA125 level alone. This marker combination showed a large odds ratio for short disease-free period in high-risk EOC groups. Functional studies revealed that ascitic ATX was required for maintaining cancer stem cell-like characteristics and invadopodia formation. CONCLUSION: Ascitic ATX levels may serve as a useful prognostic indicator for predicting aggressive behaviour in EOC. ATX-linked invadopodia are a potential target to prevent peritoneal dissemination in ovarian cancer.
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Intracellular pathogens have evolved to utilize normal cellular processes to complete their replicative cycles. Pathogens that interface with proliferative cell signaling pathways risk infections that can lead to cancers, but the factors that influence malignant outcomes are incompletely understood. Human papillomaviruses (HPVs) predominantly cause benign hyperplasia in stratifying epithelial tissues. However, a subset of carcinogenic or "high-risk" HPV (hr-HPV) genotypes are etiologically linked to nearly 5% of all human cancers. Progression of hr-HPV-induced lesions to malignancies is characterized by increased expression of the E6 and E7 oncogenes and the oncogenic functions of these viral proteins have been widely studied. Yet, the mechanisms that regulate hr-HPV oncogene transcription and suppress their expression in benign lesions remain poorly understood. Here, we demonstrate that EGFR/MEK/ERK signaling, influenced by epithelial contact inhibition and tissue differentiation cues, regulates hr-HPV oncogene expression. Using monolayer cells, epithelial organotypic tissue models, and neoplastic tissue biopsy materials, we show that cell-extrinsic activation of ERK overrides cellular control to promote HPV oncogene expression and the neoplastic phenotype. Our data suggest that HPVs are adapted to use the EGFR/MEK/ERK signaling pathway to regulate their productive replicative cycles. Mechanistic studies show that EGFR/MEK/ERK signaling influences AP-1 transcription factor activity and AP-1 factor knockdown reduces oncogene transcription. Furthermore, pharmacological inhibitors of EGFR, MEK, and ERK signaling quash HPV oncogene expression and the neoplastic phenotype, revealing a potential clinical strategy to suppress uncontrolled cell proliferation, reduce oncogene expression and treat HPV neoplasia.
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MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/virologia , MAP Quinases Reguladas por Sinal Extracelular/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Terapia de Alvo Molecular , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/terapiaRESUMO
Contact-based pericellular interactions play important roles in cancer progression via juxtacrine signaling pathways. The present study revealed that hypoxia-inducible factor-1α (HIF-1α), induced even in non-hypoxic conditions by cell-to-cell contact, was a critical cue responsible for the malignant characteristics of glioblastoma multiforme (GBM) cells through Notch1 signaling. Densely cultured GBM cells showed enhanced viability and resistance to temozolomide (TMZ) compared to GBM cells at a low density. Ablating Notch1 signaling by a γ-secretase inhibitor or siRNA transfection resensitized resistant GBM cells to TMZ treatment and decreased their viability under dense culture conditions. The expression of HIF-1α was significantly elevated in highly dense GBM cells even under non-hypoxic conditions. Atypical HIF-1α expression was associated with the Notch1 signaling pathway in both GBM and glioblastoma stem cells (GSC). Proteasomal degradation of HIF-1α was prevented by binding with Notch1 intracellular domain (NICD), which translocated to the nuclei of GBM cells. Silencing Notch1 signaling using a doxycycline-inducible Notch1 RNA-interfering system or treatment with chetomin, a HIF pathway inhibitor, retarded tumor development with a significant anti-cancer effect in a murine U251-xenograft model. Using GBM patient tissue microarray analysis, a significant increase in HIF-1α expression was identified in the group with Notch1 expression compared to the group without Notch1 expression among those with positive HIF-1α expression. Collectively, these findings highlight the critical role of cell-to-cell contact-dependent signaling in GBM progression. They provide a rationale for targeting HIF-1α signaling even in a non-hypoxic microenvironment.
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Glioblastoma , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Linhagem Celular Tumoral , Doxiciclina , Glioblastoma/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , RNA Interferente Pequeno/genética , Receptor Notch1/genética , Transdução de Sinais , Temozolomida , Microambiente TumoralRESUMO
The endangered whale shark (Rhincodon typus) is the largest fish on Earth and a long-lived member of the ancient Elasmobranchii clade. To characterize the relationship between genome features and biological traits, we sequenced and assembled the genome of the whale shark and compared its genomic and physiological features to those of 83 animals and yeast. We examined the scaling relationships between body size, temperature, metabolic rates, and genomic features and found both general correlations across the animal kingdom and features specific to the whale shark genome. Among animals, increased lifespan is positively correlated to body size and metabolic rate. Several genomic traits also significantly correlated with body size, including intron and gene length. Our large-scale comparative genomic analysis uncovered general features of metazoan genome architecture: Guanine and cytosine (GC) content and codon adaptation index are negatively correlated, and neural connectivity genes are longer than average genes in most genomes. Focusing on the whale shark genome, we identified multiple features that significantly correlate with lifespan. Among these were very long gene length, due to introns being highly enriched in repetitive elements such as CR1-like long interspersed nuclear elements, and considerably longer neural genes of several types, including connectivity, activity, and neurodegeneration genes. The whale shark genome also has the second slowest evolutionary rate observed in vertebrates to date. Our comparative genomics approach uncovered multiple genetic features associated with body size, metabolic rate, and lifespan and showed that the whale shark is a promising model for studies of neural architecture and lifespan.
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Adaptação Fisiológica/genética , Tamanho Corporal/fisiologia , Tubarões/genética , Animais , Sequência de Bases/genética , Tamanho Corporal/genética , Genoma/genética , Genômica/métodos , Longevidade/genética , Tubarões/metabolismo , TemperaturaRESUMO
BACKGROUND: An association between environmental pollutants and alcohol-related liver disease (ALD) has not been determined until now. The objectives of this study were to examine the association of the pollutants with ALD, and whether the pollutants together increased the risk of ALD. METHODS: Data were extracted from the Korea National Health and Nutrition Examination Survey (2010-2013 and 2016-2017; n = 11,993). Blood levels of lead, cadmium, and mercury were measured. ALD was defined by a combination of excessive alcohol consumption and ALD/non-alcoholic fatty liver disease index > 0. The aspartate aminotransferase-to-platelet ratio index and fibrosis (FIB)-4 score were used to evaluate ALD FIB. RESULTS: The odds ratios (ORs) of ALD for the highest versus the lowest quartiles of exposure were for lead, 7.39 (95% confidence interval [CI], 5.51-9.91); cadmium, 1.68 (95% CI, 1.32-2.14); and mercury, 5.03 (95% CI, 3.88-6.53). Adjusting for age, gender, smoking, occupation, education, and personal income attenuated the associations but indicated significant positive trends (all Ptrend < 0.001). A positive additive interaction between cadmium and lead was observed. The relative excess OR due to the interaction was 0.96 (95% CI, 0.41-1.51); synergy index = 2.92 (95% CI, 0.97-8.80). Among 951 subjects with ALD, advanced FIB was associated with lead and cadmium (OR, 3.46, 95% CI, 1.84-6.53; OR, 8.50, 95% CI, 2.54-28.42, respectively), but not with mercury. The effect estimates for lead and cadmium remained significant even after adjustment for daily alcohol intake. CONCLUSION: Blood levels of lead, cadmium, and mercury were significantly associated not only with the risk of ALD but also with ALD FIB. Cadmium and lead have synergistic effects that increase the risk of ALD.
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Poluentes Ambientais , Mercúrio , Hepatopatia Gordurosa não Alcoólica , Humanos , Cádmio , Inquéritos NutricionaisRESUMO
Selenium is a promising multi-target chemotherapeutic agent with controversial clinical results. Hence, reassessing the anticancer effects of Se is necessary to clearly understand the potential of high-dose selenium in cancer treatment. Here, we observed that high-dose sodium selenite (SS) significantly decreased the proliferation and increased the death of ovarian cancer cells, mediated by an increased generation of reactive oxygen species. Notably, high-dose SS decreased the levels of glutathione peroxidase (GPx), a selenoprotein with antioxidant properties, without altering other selenoproteins. Furthermore, high-dose SS triggered lipid peroxidation and ferroptosis, a type of iron-dependent cell death, due to dysregulated GPx4 pathways. We demonstrated that intravenous high-dose SS significantly reduced the tumor growth and weight in SKOV3-bearing mice. Consistent with our in vitro results, mice with SKOV3 cells treated with high-dose SS showed decreased GPx4 expression in tumors. Therefore, we highlight the significance of high-dose SS as a potential chemotherapeutic agent for ovarian cancer. High-dose SS-mediated ferroptotic therapy integrating glutathione depletion and ROS generation is a promising strategy for cancer therapy.
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Neoplasias Ovarianas , Selênio , Camundongos , Animais , Feminino , Humanos , Selênio/farmacologia , Selênio/metabolismo , Glutationa Peroxidase/metabolismo , Morte Celular , Selenoproteínas , Selenito de Sódio/farmacologia , Selenito de Sódio/metabolismo , Neoplasias Ovarianas/tratamento farmacológicoRESUMO
Apoptosis has historically been considered the primary form of programmed cell death (PCD) and is responsible for regulating cellular processes during development, homeostasis, and disease. Conversely, necrosis was considered uncontrolled and unregulated. However, recent evidence has unveiled the significance of necroptosis, a regulated form of necrosis, as an important mechanism of PCD alongside apoptosis. The activation of necroptosis leads to cellular membrane disruption, inflammation, and vascularization. This process is crucial in various pathological conditions, including intervertebral disc degeneration (IVDD), neurodegeneration, inflammatory diseases, multiple cancers, and kidney injury. In recent years, extensive research efforts have shed light on the molecular regulation of the necroptotic pathway. Various stimuli trigger necroptosis, and its regulation involves the activation of specific proteins such as receptor-interacting protein kinase 1 (RIPK1), RIPK3, and the mixed lineage kinase domain-like (MLKL) pseudokinase. Understanding the intricate mechanisms governing necroptosis holds great promise for developing novel therapeutic interventions targeting necroptosis-associated IVDD. The objective of this review is to contribute to the growing body of scientific knowledge in this area by providing a comprehensive overview of necroptosis and its association with IVDD. Ultimately, these understandings will allow the development of innovative drugs that can modulate the necroptotic pathway, offering new therapeutic avenues for individuals suffering from necroptosis.
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Degeneração do Disco Intervertebral , Proteínas Quinases , Humanos , Proteínas Quinases/metabolismo , Necroptose/fisiologia , Apoptose , Necrose/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismoRESUMO
Protein tyrosine kinase 7 (PTK7), a catalytically defective receptor tyrosine kinase (RTK), is often upregulated in various cancers. This study aimed to validate PTK7 as a target for breast cancer (BC) and investigate its oncogenic signaling mechanism. BC tissue analysis showed significantly elevated PTK7 mRNA levels, especially in refractory triple-negative breast cancer (TNBC) tissues, compared with normal controls. Similarly, BC cell lines exhibited increased PTK7 expression. Knockdown of PTK7 inhibited the proliferation of T-47D and MCF-7 hormone-receptor-positive BC cell-lines and of HCC1187, MDA-MB-231, MDA-MB-436, and MDA-MB-453 TNBC cells. PTK7 knockdown also inhibited the adhesion, migration, and invasion of MDA-MB-231, MDA-MB-436, and MDA-MB-453 cells, and reduced the phosphorylation levels of crucial oncogenic regulators including extracellular signal-regulated kinase (ERK), Akt, and focal adhesion kinase (FAK). Furthermore, PTK7 interacts with fibroblast growth factor receptor 1 (FGFR1) and epidermal growth factor receptor (EGFR) expressed in MDA-MB-231 cells. Knockdown of PTK7 decreased the growth-factor-induced phosphorylation of FGFR1 and EGFR in MDA-MB-231 cells, indicating its association with RTK activation. In conclusion, PTK7 plays a significant role in oncogenic signal transduction by enhancing FGFR1 and EGFR activation, influencing BC tumorigenesis and metastasis. Hence, PTK7 represents a potential candidate for targeted BC therapy, including TNBC.
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Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Transdução de Sinais , Fosforilação , Receptores ErbB/genética , Receptores ErbB/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Moléculas de Adesão Celular/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismoRESUMO
A lot of nanomaterials have been applied to various nano-biotechnological fields, such as contrast agents, drug or gene delivery systems, cosmetics, and so on. Despite the expanding usage of nanomaterials, concerns persist regarding their potential toxicity. To address this issue, many scientists have tried to develop biocompatible nanomaterials containing phytochemicals as a promising solution. In this study, we synthesized biocompatible nanomaterials by using gallic acid (GA), which is a phytochemical, and coating it onto the surface of iron oxide nanoparticles (IONPs). Importantly, the GA-modified iron oxide nanoparticles (GA-IONPs) were successfully prepared through environmentally friendly methods, avoiding the use of harmful reagents and extreme conditions. The presence of GA on the surface of IONPs improved their stability and bioactive properties. In addition, cell viability assays proved that GA-IONPs possessed excellent biocompatibility in human dermal papilla cells (HDPCs). Additionally, GA-IONPs showed antioxidant activity, which reduced intracellular reactive oxygen species (ROS) levels in an oxidative stress model induced by hydrogen peroxide (H2O2). To investigate the impact of GA-IONPs on exosome secretions from oxidative stress-induced cells, we analyzed the number and characteristics of exosomes in the culture media of HDPCs after H2O2 stimulation or GA-IONP treatment. Our analysis revealed that both the number and proportions of tetraspanins (CD9, CD81, and CD63) in exosomes were similar in the control group and the GA-IONP-treated groups. In contrast, exosome secretion was increased, and the proportion of tetraspanin was changed in the H2O2-treated group compared to the control group. It demonstrated that treatment with GA-IONPs effectively attenuated exosome secretion induced by H2O2-induced oxidative stress. Therefore, this GA-IONP exhibited outstanding promise for applications in the field of nanobiotechnology.
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Antioxidantes , Nanopartículas , Humanos , Antioxidantes/farmacologia , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo , Espécies Reativas de Oxigênio , Nanopartículas Magnéticas de Óxido de Ferro , Nanopartículas/química , Compostos Férricos/farmacologia , Compostos Férricos/químicaRESUMO
BACKGROUND: The accuracy of intraoral scanning plays a crucial role in the workflow of computer-assisted design/computer-assisted manufacturing. However, data regarding scanning accuracy for inlay preparation designs are lacking. The purpose of this in vitro study was to evaluate the influence of the depth of the occlusal cavity and width of the gingival floor of the proximal box on the trueness and precision of intraoral scans for inlay restoration. METHODS: Artificial teeth were used in this study. Four types of preparations for mesio-occlusal inlay were performed on each #36 artificial tooth depending on two different depths of the occlusal cavity (1 mm and 2 mm) and widths of the gingival floor of the proximal box (1.5 mm and 2.5 mm). Artificial teeth were scanned 10 times each with Cerec Primescan AC, and another scan was performed subsequently with a laboratory scanner as a reference (n = 10). Standard tessellation language files were analyzed using a three-dimensional analysis software program. Experimental data were analyzed using two-way analysis of variance and the Bonferroni multiple comparison test. RESULTS: The narrow shallow group had significantly higher deviation values for trueness than the wide deep group (p < 0.05). The wide deep group had the lowest average deviation value for trueness and there was no significant difference between the narrow deep and wide shallow groups (p > 0.05). For the mean maximum positive deviation, the wide groups had significantly lower values than the narrow groups (p < 0.05). Trueness was affected by both the width and depth(p < 0.05), whereas the mean maximum positive deviation was affected by the width (p < 0.05). The mean maximum negative deviation was affected by all three factors (p < 0.05). Precision was affected by the depth and the interaction between the depth of the occlusal cavity and width of the gingival floor (p < 0.05). CONCLUSIONS: The design of different inlay cavity configurations affected the accuracy of the digital intraoral scanner. The highest average deviation for trueness was observed in the narrow shallow group and the lowest in the wide deep group. With regard to precision, the narrow shallow group showed the lowest average deviation, and the narrow deep group showed highest value.
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Cárie Dentária , Restaurações Intracoronárias , Humanos , Desenho Assistido por Computador , Assistência Odontológica , GengivaRESUMO
INTRODUCTION: Digital feedback for tooth preparation can provide dental practitioners with more objective and accurate evaluations compared to conventional methods. This study aimed to evaluate the educational effect and satisfaction of digital feedback compared with those of the conventional putty index method for tooth preparation. MATERIAL AND METHODS: Forty-eight third-grade dental students were selected. All students performed a full-coverage preparation on a right mandibular first molar resin tooth. They were randomly divided into four groups (n = 12)-no guide (control), putty index, digital feedback, and digital and putty index assessment. Three-dimensional analysis was performed using an analysis software (GomInspect 2018, Gom) to evaluate the amount of tooth structure removed. At the end of the practice, the students completed a questionnaire to evaluate the educational satisfaction of the respective methods. RESULTS: There was no statistical significance of the amount of preparation amongst groups in most of the measured areas only except for several specific points. Overall occlusal surface showed 0.99 ± 0.27 mm in the N group (no guide) and 1.15 ± 0.31 mm in the D group (digital feedback), and overall axial surface showed no statistical differences (p > .05). The groups that used digital assessment showed a high level of satisfaction compared with conventional assessment. CONCLUSIONS: It was difficult to confirm that the digital-based feedback promotes accurate tooth preparation compared to conventional feedback within the limitation of this study. However, it improved educational satisfaction and permitted objective evaluation.
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Odontólogos , Avaliação Educacional , Humanos , Coroas , Educação em Odontologia/métodos , Avaliação Educacional/métodos , Papel Profissional , Preparo do DenteRESUMO
AIM: This study aimed to evaluate the intaglio surface trueness and fit of zirconia crowns depending on the different machining strategies used with the CEREC system. MATERIALS AND METHODS: Thirty duplicate tooth models for a single zirconia crown were randomly assigned to the three groups (n = 10) according to the machining mode used for fabrication: grinding, wet milling, and dry milling. The scan data of the final crowns were compared to their design data to evaluate the intaglio surface trueness. The marginal and internal fits were evaluated using the cross-sectional method. The time required for the machining and sintering processes was measured for each group. RESULT: The wet milling group showed better trueness (RMS, 13.8 ± 1.0 µm) than the grinding and dry milling groups (p < 0.001). The marginal gap was greater in the grinding group (58.6 ± 28.9 µm) than that in the wet milling and dry milling groups (p < 0.001). The dry milling group required the shortest time for the manufacturing process. CONCLUSION: All machining modes fabricated crowns with a clinically acceptable trueness and fit. However, the dry milling mode was advantageous for the chairside CAD/CAM system with respect to time efficiency.
RESUMO
NANOG engages with tumour initiation and metastasis by regulating the epithelial-mesenchymal transition (EMT) in epithelial ovarian cancer (EOC). However, its role in association with pAMPKα, and its clinical significance in EOC have not been elucidated even though AMPK is known to degrade NANOG in various human cancers. Hence, we investigated the role of pAMPKα and its association with NANOG as potential prognostic biomarkers in EOC. Both NANOG and pAMPKα expression were significantly overexpressed in EOCs comparing nonadjacent normal epithelial tissues, benign tissues, and borderline tumours. NANOG overexpression was significantly associated with poor disease-free survival (DFS) and overall survival (OS), whereas pAMPKα overexpression was associated with good DFS and OS. Importantly, multivariate analysis revealed that the combination of high NANOG and low pAMPKα expression was a poor independent prognostic factor for DFS and was associated with platinum resistance. In ovarian cancer cell lines, siRNA-mediated NANOG knockdown diminished migration and invasion properties by regulating the EMT process via the AMPK/mTOR signalling pathway. Furthermore, treatment with AMPK activator suppressed expression of stemness factors such as NANOG, Oct4 and Sox2. Collectively, these findings established that the combination of high NANOG and low pAMPKα expression was associated with EOC progression and platinum resistance, suggesting a potential prognostic biomarker for clinical management in EOC patients.