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1.
Mol Ther ; 32(10): 3618-3628, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39066480

RESUMO

Multiple pathogenic single-nucleotide polymorphisms (SNPs) have been identified as contributing factors in the aggravation of cancer prognosis and emergence of drug resistance in various cancers. Here, we targeted mutated EGFR and TP53 oncogenes harboring single-nucleotide missense mutations (EGFR-T790M and TP53-R273H) that are associated with gefitinib resistance. Co-delivery of adenine base editor (ABE) and EGFR- and TP53-SNP specific single-guide RNA via adenovirus (Ad) resulted in precise correction of the oncogenic mutations with high accuracy and efficiency in vitro and in vivo. Importantly, compared with a control group treated only with gefitinib, an EGFR inhibitor, co-treatment with Ad/ABE targeting SNPs in TP53 and EGFR in combination with gefitinib increased drug sensitivity and suppressed abnormal tumor growth more efficiently. Taken together, these results indicate that ABE-mediated correction of dual oncogenic SNPs can be an effective strategy for the treatment of drug-resistant cancers.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Receptores ErbB , Gefitinibe , Neoplasias Pulmonares , Proteína Supressora de Tumor p53 , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sistemas CRISPR-Cas , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Edição de Genes , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Mutação , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Mol Cancer ; 23(1): 45, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424542

RESUMO

BACKGROUND: In the myeloid compartment of the tumor microenvironment, CD244 signaling has been implicated in immunosuppressive phenotype of monocytes. However, the precise molecular mechanism and contribution of CD244 to tumor immunity in monocytes/macrophages remains elusive due to the co-existing lymphoid cells expressing CD244. METHODS: To directly assess the role of CD244 in tumor-associated macrophages, monocyte-lineage-specific CD244-deficient mice were generated using cre-lox recombination and challenged with B16F10 melanoma. The phenotype and function of tumor-infiltrating macrophages along with antigen-specific CD8 T cells were analyzed by flow cytometry and single cell RNA sequencing data analysis, and the molecular mechanism underlying anti-tumorigenic macrophage differentiation, antigen presentation, phagocytosis was investigated ex vivo. Finally, the clinical feasibility of CD244-negative monocytes as a therapeutic modality in melanoma was confirmed by adoptive transfer experiments. RESULTS: CD244fl/flLysMcre mice demonstrated a significant reduction in tumor volume (61% relative to that of the CD244fl/fl control group) 14 days after tumor implantation. Within tumor mass, CD244fl/flLysMcre mice also showed higher percentages of Ly6Clow macrophages, along with elevated gp100+IFN-γ+ CD8 T cells. Flow cytometry and RNA sequencing data demonstrated that ER stress resulted in increased CD244 expression on monocytes. This, in turn, impeded the generation of anti-tumorigenic Ly6Clow macrophages, phagocytosis and MHC-I antigen presentation by suppressing autophagy pathways. Combining anti-PD-L1 antibody with CD244-/- bone marrow-derived macrophages markedly improved tumor rejection compared to the anti-PD-L1 antibody alone or in combination with wild-type macrophages. Consistent with the murine data, transcriptome analysis of human melanoma tissue single-cell RNA-sequencing dataset revealed close association between CD244 and the inhibition of macrophage maturation and function. Furthermore, the presence of CD244-negative monocytes/macrophages significantly increased patient survival in primary and metastatic tumors. CONCLUSION: Our study highlights the novel role of CD244 on monocytes/macrophages in restraining anti-tumorigenic macrophage generation and tumor antigen-specific T cell response in melanoma. Importantly, our findings suggest that CD244-deficient macrophages could potentially be used as a therapeutic agent in combination with immune checkpoint inhibitors. Furthermore, CD244 expression in monocyte-lineage cells serve as a prognostic marker in cancer patients.


Assuntos
Melanoma , Monócitos , Humanos , Animais , Camundongos , Monócitos/metabolismo , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Macrófagos/metabolismo , Linfócitos T CD8-Positivos , Carcinogênese/metabolismo , Microambiente Tumoral , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo
3.
J Neuroinflammation ; 21(1): 250, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367382

RESUMO

BACKGROUND: IL-2 regulates T cell differentiation: low-dose IL-2 induces immunoregulatory Treg differentiation, while high-dose IL-2 acts as a potent activator of cytotoxic T cells and NK cells. Therefore, high-dose IL-2 has been studied for use in cancer immunotherapy. We aimed to utilize low-dose IL-2 to treat inflammatory diseases such as obesity and insulin resistance, which involve low-grade chronic inflammation. MAIN BODY: Systemic administration of low-dose IL-2 increased Treg cells and decreased inflammation in gonadal white adipose tissue (gWAT), leading to improved insulin sensitivity in high-fat diet-fed obese mice. Additionally, central administration of IL-2 significantly enhanced insulin sensitivity through the activation of the sympathetic nervous system. The sympathetic signaling induced by central IL-2 administration not only decreased interferon γ (IFNγ) + Th1 cells and the expression of pro-inflammatory cytokines, including Il-1ß, Il-6, and Il-8, but also increased CD4 + CD25 + FoxP3 + Treg cells and Tgfß expression in the gWAT of obese mice. These phenomena were accompanied by hypothalamic microgliosis and activation of pro-opiomelanocortin neurons. Furthermore, sympathetic denervation in gWAT reversed the enhanced insulin sensitivity and immune cell polarization induced by central IL-2 administration. CONCLUSION: Overall, we demonstrated that IL-2 improves insulin sensitivity through two mechanisms: direct action on CD4 + T cells and via the neuro-immune axis triggered by hypothalamic microgliosis.


Assuntos
Hipotálamo , Resistência à Insulina , Interleucina-2 , Camundongos Endogâmicos C57BL , Obesidade , Sistema Nervoso Simpático , Animais , Camundongos , Resistência à Insulina/fisiologia , Interleucina-2/metabolismo , Obesidade/metabolismo , Hipotálamo/metabolismo , Hipotálamo/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Masculino , Dieta Hiperlipídica/efeitos adversos , Camundongos Obesos , Linfócitos T Reguladores/efeitos dos fármacos
4.
Plant Dis ; 108(5): 1174-1178, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105454

RESUMO

Erwinia amylovora, the causal agent of fire blight disease, has become a serious threat to the pome fruit industry in Korea since 2015. In this study, we showed that two new isolates of E. amylovora, Ea17-2187 and Ea19-7, obtained from pear orchards in Anseong, Korea, exhibited unique pathogenicity compared with other isolates thus far. Both were nonpathogenic to immature apple fruits but occasionally caused disease on immature pear fruits at varying reduced rates. Bioinformatic analyses revealed that their genomes are highly similar to those of the type strains TS3128 and ATCC49946 but have different mutations in essential virulence regulatory genes. Ea17-2187 has a single nucleotide substitution in rcsC, which encodes the core components of the Rcs system that activates the exopolysaccharide amylovoran production. In contrast, Ea19-7 contains a single nucleotide insertion in hrpL, which encodes a master regulator of the type III secretion system. In both cases, the mutation can cause premature termination and production of truncated gene products, disrupting virulence regulation. Introduction of the nonmutated rcsC and hrpL genes into Ea17-2187 and Ea19-7, respectively, fully recovered pathogenicity, comparable with that of TS3128; hence, these mutations were responsible for the altered pathogenicity observed. Interestingly, virulence assays on immature pear fruits showed that the hrpL mutant of Ea19-7 was still pathogenic, although its virulence level was markedly reduced. Taken together, these results suggest that the two new isolates might act as opportunistic pathogens or cheaters and that some Korean isolates might have evolved to acquire alternative pathways for activating pathogenicity factors.


Assuntos
Erwinia amylovora , Doenças das Plantas , Pyrus , Erwinia amylovora/genética , Erwinia amylovora/patogenicidade , Doenças das Plantas/microbiologia , Pyrus/microbiologia , Virulência/genética , República da Coreia , Polimorfismo de Nucleotídeo Único , Proteínas de Bactérias/genética , Malus/microbiologia , Genoma Bacteriano , Frutas/microbiologia , Polissacarídeos Bacterianos
5.
Acta Neuropsychiatr ; : 1-9, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39463399

RESUMO

Childhood trauma can cause deficits in emotional regulation. However, few studies have investigated childhood trauma and emotional regulation skills in patients with mood disorders. We aimed to investigate how childhood trauma and Emotion Regulation Skills Questionnaire (ERSQ) scores are associated with mood disorders.This study included 779 patients with mood disorders (major depressive disorder [MDD, n = 240], bipolar I disorder [BDI, n = 121], and bipolar II disorder [BDII, n = 418]). We used their Childhood Trauma Questionnaire-Short Form (CTQ) and ERSQ scores for the evaluation.The between-group differences in CTQ and ERSQ scores were examined. The CTQ and ERSQ total scores were negatively correlated. Among the CTQ subscales, emotional neglect showed a significant correlation with the ERSQ total score, whereas acceptance and tolerance showed higher negative correlations with the CTQ than with the other ERSQ subscales. The negative relationship between emotional regulation and childhood trauma varied significantly depending on the group, with the BDI group showing a more prominent association than the other groups.Based on various mood disorders, we observed associations between childhood trauma and emotional regulation skills. Consequently, our study offers notable insights for future research on the impact of childhood trauma on ERSQ.

6.
Am J Hum Genet ; 106(5): 717-725, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32330417

RESUMO

We identified three unrelated individuals with de novo missense variants in CDK19, encoding a cyclin-dependent kinase protein family member that predominantly regulates gene transcription. These individuals presented with hypotonia, global developmental delay, epileptic encephalopathy, and dysmorphic features. CDK19 is conserved between vertebrate and invertebrate model organisms, but currently abnormalities in CDK19 are not known to be associated with a human disorder. Loss of Cdk8, the fly homolog of CDK19, causes larval lethality, which is suppressed by expression of human CDK19 reference cDNA. In contrast, the CDK19 p.Tyr32His and p.Thr196Ala variants identified in the affected individuals fail to rescue the loss of Cdk8 and behave as null alleles. Additionally, neuronal RNAi-mediated knockdown of Cdk8 in flies results in semi-lethality. The few eclosing flies exhibit severe seizures and a reduced lifespan. Both phenotypes are fully suppressed by moderate expression of the CDK19 reference cDNA but not by expression of the two variants. Finally, loss of Cdk8 causes an obvious loss of boutons and synapses at larval neuromuscular junctions (NMJs). Together, our findings demonstrate that human CDK19 fully replaces the function of Cdk8 in the fly, the human disease-associated CDK19 variants behave as strong loss-of-function variants, and deleterious CDK19 variants underlie a syndromic neurodevelopmental disorder.


Assuntos
Encefalopatias/genética , Quinases Ciclina-Dependentes/genética , Epilepsia Generalizada/genética , Deficiência Intelectual/genética , Mutação de Sentido Incorreto/genética , Adulto , Sequência de Aminoácidos , Animais , Pré-Escolar , Quinase 8 Dependente de Ciclina/deficiência , Quinase 8 Dependente de Ciclina/genética , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Junção Neuromuscular , Doenças Raras/genética , Convulsões/genética , Síndrome , Adulto Jovem
7.
Small ; 19(34): e2300290, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37127866

RESUMO

This study suggests a Ru/ZnO bilayer grown using area-selective atomic layer deposition (AS-ALD) as a multifunctional layer for advanced Cu metallization. As a diffusion barrier and glue layer, ZnO is selectively grown on SiO2 , excluding Cu, where Ru, as a liner and seed layer, is grown on both surfaces. Dodecanethiol (DDT) is used as an inhibitor for the AS-ALD of ZnO using diethylzinc and H2 O at 120 °C. H2 plasma treatment removes the DDT adsorbed on Cu, forming inhibitor-free surfaces. The ALD-Ru film is then successfully deposited at 220 °C using tricarbonyl(trimethylenemethane)ruthenium and O2 . The Cu/bilayer/Si structural and electrical properties are investigated to determine the diffusion barrier performance of the bilayer film. Copper silicide is not formed without the conductivity degradation of the Cu/bilayer/Si structure, even after annealing at 700 °C. The effect of ZnO on the Ru/SiO2 structure interfacial adhesion energy is investigated using a double-cantilever-beam test and is found to increase with ZnO between Ru and SiO2 . Consequently, the Ru/ZnO bilayer can be a multifunctional layer for advanced Cu interconnects. Additionally, the formation of a bottomless barrier by eliminating ZnO on the via bottom, or Cu, is expected to decrease the via resistance for the ever-shrinking Cu lines.

8.
J Med Virol ; 95(7): e28894, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37386895

RESUMO

Severe fever with thrombocytopenia syndrome virus (SFTSV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause the hyperproduction of inflammatory cytokines, which have pathological effects in patient including severe or fatal cytokine storms. To characterize the effect of SFTSV and SARS-CoV-2 infection on the production of cytokines in severe fever with thrombocytopenia syndrome (SFTS) and COVID-19 patients, we performed an analysis of cytokines in SFTS and COVID-19 patients and also investigated the role of interleukin-10 (IL-10) in vitro studies: lipopolysaccharide-induced THP-1-derived macrophages, SFTSV infection of THP-1 cells, and SARS-CoV-2 infection of THP-1 cells. In this study, we found that levels of both IL-10 and IL-6 were significantly elevated, the level of transforming growth factor-ß (TGF-ß) was significantly decreased and IL-10 was elevated earlier than IL-6 in severe and critical COVID-19 and fatal SFTS patients, and inhibition of IL-10 signaling decreased the production of IL-6 and elevated that of TGF-ß. Therefore, the hyperproduction of IL-10 and IL-6 and the low production of TGF-ß have been linked to cytokine storm-induced mortality in fatal SFTS and severe and critically ill COVID-19 patients and that IL-10 can play an important role in the host immune response to severe and critical SARS-CoV-2 and fatal SFTSV infection.


Assuntos
COVID-19 , Febre Grave com Síndrome de Trombocitopenia , Humanos , Síndrome da Liberação de Citocina , Citocinas , Interleucina-10 , Interleucina-6 , SARS-CoV-2 , Fator de Crescimento Transformador beta
9.
J Appl Microbiol ; 134(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37974046

RESUMO

AIMS: The objectives of this study were to evaluate the effect of combination treatment with cold plasma (CP), vacuum packaging (VP), and hot water (HW) on the inactivation of foodborne pathogens on buckwheat seeds, and determined the germination rates of seeds and the quality of sprouts following combination treatment. METHODS AND RESULTS: Buckwheat seeds inoculated with Salmonella Typhimurium and Listeria monocytogenes were treated with CP, HW, CP + HW, VP + HW, or CP + VP + HW. The germination rates of the HW-, CP + HW-, VP + HW-, and CP + VP + HW-treated seeds and the antioxidant activities and rutin contents of the CP + HW- and CP + VP + HW-treated sprouts were determined. HW, CP + HW, and CP + VP + HW were found to reduce the levels of the two pathogens to below the detection limit (1.0 log CFU g-1) at 70°C. However, HW and CP + HW significantly reduced the germination rate of buckwheat seeds. CP + VP + HW did not affect the germination rate of seeds nor the antioxidant activities and rutin content of buckwheat sprouts. CONCLUSIONS: These results indicate that CP + VP + HW can be used as a novel control method to reduce foodborne pathogens in seeds without causing quality deterioration.


Assuntos
Fagopyrum , Listeria monocytogenes , Salmonella typhimurium , Vácuo , Antioxidantes , Microbiologia de Alimentos , Contagem de Colônia Microbiana , Água , Sementes , Rutina/farmacologia , Germinação
10.
BMC Biol ; 20(1): 270, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36464676

RESUMO

BACKGROUND: Recently, bacterial extracellular vesicles (EVs) have been considered to play crucial roles in various biological processes and have great potential for developing cancer therapeutics and biomedicine. However, studies on bacterial EVs have mainly focused on outer membrane vesicles released from gram-negative bacteria since the outermost peptidoglycan layer in gram-positive bacteria is thought to preclude the release of EVs as a physical barrier. RESULTS: Here, we examined the ultrastructural organization of the EV produced by gram-positive bacteria using super-resolution stochastic optical reconstruction microscopy (STORM) at the nanoscale, which has not been resolved using conventional microscopy. Based on the super-resolution images of EVs, we propose three major mechanisms of EV biogenesis, i.e., membrane blebbing (mechanisms 1 and 2) or explosive cell lysis (mechanism 3), which are different from the mechanisms in gram-negative bacteria, despite some similarities. CONCLUSIONS: These findings highlight the significant role of cell wall degradation in regulating various mechanisms of EV biogenesis and call for a reassessment of previously unresolved EV biogenesis in gram-positive bacteria.


Assuntos
Fenômenos Biológicos , Vesículas Extracelulares , Microscopia , Bactérias Gram-Positivas , Morte Celular
11.
Nano Lett ; 22(16): 6537-6544, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35900218

RESUMO

Applying an electric-field (E-field) during antibody immobilization aligns the orientation of the antibody on the biosensor surface, thereby enhancing the binding probability between the antibody and antigen and maximizing the sensitivity of the biosensor. In this study, a biosensor with enhanced antibody-antigen binding probability was developed using the alignment of polar antibodies (immunoglobulin G [IgG]) under an E-field applied inside the interdigitated electrodes. The optimal alignment condition was first theoretically calculated and then experimentally confirmed by comparing the impedance change before and after the alignment of IgG (a purified anti-ß-amyloid antibody). With the optimized condition, the impedance change of the biosensor was maximized because of the alignment of IgG orientation on the sensor surface; the detection sensitivity of the antigen amyloid-beta 1-42 was also maximized. The E-field-based in-sensor alignment of antibodies is an easy and effective method for enhancing biosensor sensitivity.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Impedância Elétrica , Eletricidade , Eletrodos , Imunoglobulina G
12.
Am J Hum Genet ; 105(6): 1237-1253, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31785787

RESUMO

We report an early-onset autosomal-recessive neurological disease with cerebellar atrophy and lysosomal dysfunction. We identified bi-allelic loss-of-function (LoF) variants in Oxidative Resistance 1 (OXR1) in five individuals from three families; these individuals presented with a history of severe global developmental delay, current intellectual disability, language delay, cerebellar atrophy, and seizures. While OXR1 is known to play a role in oxidative stress resistance, its molecular functions are not well established. OXR1 contains three conserved domains: LysM, GRAM, and TLDc. The gene encodes at least six transcripts, including some that only consist of the C-terminal TLDc domain. We utilized Drosophila to assess the phenotypes associated with loss of mustard (mtd), the fly homolog of OXR1. Strong LoF mutants exhibit late pupal lethality or pupal eclosion defects. Interestingly, although mtd encodes 26 transcripts, severe LoF and null mutations can be rescued by a single short human OXR1 cDNA that only contains the TLDc domain. Similar rescue is observed with the TLDc domain of NCOA7, another human homolog of mtd. Loss of mtd in neurons leads to massive cell loss, early death, and an accumulation of aberrant lysosomal structures, similar to what we observe in fibroblasts of affected individuals. Our data indicate that mtd and OXR1 are required for proper lysosomal function; this is consistent with observations that NCOA7 is required for lysosomal acidification.


Assuntos
Atrofia/patologia , Doenças Cerebelares/patologia , Lisossomos/patologia , Proteínas Mitocondriais/metabolismo , Doenças do Sistema Nervoso/patologia , Estresse Oxidativo , Adolescente , Adulto , Animais , Atrofia/genética , Atrofia/metabolismo , Doenças Cerebelares/genética , Doenças Cerebelares/metabolismo , Criança , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Lisossomos/metabolismo , Masculino , Proteínas Mitocondriais/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Linhagem , Fenótipo , Adulto Jovem
13.
Sensors (Basel) ; 20(11)2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32517305

RESUMO

Since separation of target biomolecules is a crucial step for highly sensitive and selective detection of biomolecules, hence, various technologies have been applied to separate biomolecules, such as deoxyribonucleic acid (DNA), protein, exosome, virus, etc. Among the various technologies, dielectrophoresis (DEP) has the significant advantage that the force can provide two different types of forces, attractive and repulsive DEP force, through simple adjustment in frequency or structure of microfluidic chips. Therefore, in this review, we focused on separation technologies based on DEP force and classified various separation technologies. First, the importance of biomolecules, general separation methods and various forces including DEP, electrophoresis (EP), electrothermal flow (ETF), electroosmosis (EO), magnetophoresis, acoustophoresis (ACP), hydrodynamic, etc., was described. Then, separating technologies applying only a single DEP force and dual force, moreover, applying other forces simultaneously with DEP force were categorized. In addition, advanced technologies applying more than two different kinds of forces, namely complex force, were introduced. Overall, we critically reviewed the state-of-the-art of converged various forces for detection of biomolecules with novelty of DEP.


Assuntos
Técnicas Eletroquímicas , Técnicas Analíticas Microfluídicas , DNA/isolamento & purificação , Eletroforese , Osmose , Proteínas/isolamento & purificação , Vírus/isolamento & purificação
14.
Int J Mol Sci ; 21(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731602

RESUMO

Stress granules are membraneless organelles composed of numerous components including ribonucleoproteins. The stress granules are characterized by a dynamic complex assembly in response to various environmental stressors, which has been implicated in the coordinated regulation of diverse biological pathways, to exert a protective role against stress-induced cell death. Here, we show that stress granule formation is induced by morusin, a novel phytochemical displaying antitumor capacity through barely known mechanisms. Morusin-mediated induction of stress granules requires activation of protein kinase R (PKR) and subsequent eIF2α phosphorylation. Notably, genetic inactivation of stress granule formation mediated by G3BP1 knockout sensitized cancer cells to morusin treatment. This protective function against morusin-mediated cell death can be attributed at least in part to the sequestration of receptors for activated C kinase-1 (RACK1) within the stress granules, which reduces caspase-3 activation. Collectively, our study provides biochemical evidence for the role of stress granules in suppressing the antitumor capacity of morusin, proposing that morusin treatment, together with pharmacological inhibition of stress granules, could be an efficient strategy for targeting cancer.


Assuntos
Apoptose/efeitos dos fármacos , Grânulos Citoplasmáticos/metabolismo , Flavonoides/farmacologia , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Receptores de Quinase C Ativada/metabolismo , eIF-2 Quinase/metabolismo , Grânulos Citoplasmáticos/patologia , Células HCT116 , Células HeLa , Humanos , Células PC-3
15.
J Nanosci Nanotechnol ; 19(4): 2298-2301, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30486986

RESUMO

We optimize various gate head structures to improve breakdown voltage characteristics of AlGaN/GaN high-electron mobility transistors by a two-dimensional device simulator based on a T-shaped gate-connected field-plate. Field-plates (FPs) alleviate electric field spikes near the gate and drain-side overlapping edges, which eventually disperse electron avalanche and charge trapping effects. Hence, the more uniform electric field distribution provides improved breakdown voltage of the device. Multiple configurations, such as extension of the FP towards the source or drain, and symmetric extension, were investigated and compared. The best results were acquired when the FP was extended towards the drain, with an optimum length of 2 µm, which produced maximum breakdown voltage of 224 V and maximum transconductance of 132.5 mS/mm. Also, the optimum Si3N4 passivation layer thickness based on a T-shaped gate-connected FP structure was 50 nm.

16.
J Nanosci Nanotechnol ; 18(3): 2041-2044, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448708

RESUMO

In this study, we present the microwave-assisted growth (MAG) of ZnO nanorods (ZNRs) using a preheating hydrothermal method under tailored preheating and postheating growth conditions. The perimeters such as solution concentration, preheating time, and postheating time, were changed to optimize ZNR growth and the growth was carried out in a domestic 850 watt microwave oven. Preheated solution was utilized as an accelerator to increase the aspect ratio of the ZNRs and reduce the fabrication time. Because of a long fabrication time and limited length in the conventional MAG method, preheating condition was used for efficient growth of nanorods through homogeneous nucleation in the solution and then heterogeneous nucleation of the formed ZNRs on seeded substrate during postheating process. The nanostructures were characterized with scanning electron microscopy to look at the morphology and dimensions. Dimensions of ZNRs kept on increasing as the molar concentration went higher. Preheating time highly affected the morphology, dimensions, and aspect ratio of ZNRs and postheating time not only ensured the stability of ZNRs with substrate due to heterogeneous nucleation process but also influenced the morphology of ZNRs.

17.
J Korean Med Sci ; 33(6): e35, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29349936

RESUMO

BACKGROUND: Multiple studies have been reported regarding preeclampsia as a possible risk factor of cerebrovascular disease (CVD). However, the correlation of preeclampsia and CVD, whether it is a cause-effect relationship or they are sharing common predisposing condition, is not well understood. Therefore, the aim of this study was to investigate the association between the preeclampsia during pregnancy and development of postpartum CVD. METHODS: A total of 1,384,550 Korean women who had a delivery between January 1, 2010 and December 31, 2012, were enrolled. Women with the risk of CVD within 1 year prior to pregnancy were excluded based on the Charlson comorbidity index. Primary endpoint was the event of CVD within a year from delivery. After exclusion, 1,075,061 women were analyzed. RESULTS: During the follow-up of 1 year postpartum, there were 25,577 preeclampsia out of 1,072,041 women without postpartum CVD (2.39%), and 121 of 3,020 women with postpartum CVD had preeclampsia before delivery (4.01%). In multivariate logistic regression analysis, women who had preeclampsia during pregnancy showed a higher risk for postpartum CVD (odds ratio, 1.64; 95% confidence interval, 1.37-1.98). CONCLUSION: The incidence of CVD after delivery was higher in women who had preeclampsia during pregnancy.


Assuntos
Transtornos Cerebrovasculares/diagnóstico , Pré-Eclâmpsia/diagnóstico , Adulto , Povo Asiático , Transtornos Cerebrovasculares/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Incidência , Modelos Logísticos , Razão de Chances , Período Pós-Parto , Gravidez , República da Coreia , Fatores de Risco
18.
J Exp Psychol Gen ; 153(7): 1765-1789, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38780566

RESUMO

Many social ties end when one side rejects the other, but rejection does not need to happen directly. Ghosting-the act of ending a relationship by ignoring another person's attempts to connect-is a common way of ending social ties. The present experiments first establish the key characteristics of ghosting and distinguish it from other rejection behaviors (Pilot Studies 1a-1c). The experiments then proceed to explore the relational and motivational implications of this behavior, finding that ghosters (those who ghost) care about the well-being of ghostees (those who are ghosted) more than ghostees realize. This result occurs in recalled instances of ghosting (Experiment 1), when ghosting in real time (Experiment 2), and when refraining from ghosting is monetarily costly (Experiment 3). We find that this occurs partly because ghostees underestimate the other-oriented motives involved in ghosting, misunderstanding that ghosters ghost partly as a way to end a tie while avoiding hurting ghostees' feelings (Experiments 4-6). Indeed, greater other-oriented motives lead to a higher likelihood of ghosting others (Experiment 7). A final experiment finds relational consequences whereby ghostees miss out on opportunities for future help exchange due to their underestimation of the extent to which ghosters care about them (Experiment 8). Ghosting is social rejection without explanation or feedback, but not without care. This study highlights how prosocial motives can drive rejection behaviors and the role of interpersonal accuracy in mitigating the negative effects of social rejection. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Distância Psicológica , Humanos , Masculino , Feminino , Adulto , Relações Interpessoais , Motivação , Adulto Jovem , Interação Social , Rejeição em Psicologia , Comportamento Social
19.
Biosens Bioelectron ; 246: 115867, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38086307

RESUMO

Graphene oxide (GO) has many advantages, making it suitable for various applications. However, it has low electrical conductivity, restricting its applicability to electrochemical biosensors. This study used dielectrophoretic (DEP) force to control the movement and deformation of GO nanosheets to achieve high electrical conductivity without the chemical reduction of oxygen functional groups. Subjecting the DEP force to GO nanosheets induced physical deformation leading to the formation of wrinkled structures. A computational simulation was performed to set an appropriate electrical condition for operating a positive DEP force effect of at least 1019 v2/m3, and the interdigitated microelectrode structure was selected. The resulting wrinkled GO exhibited significantly improved electrical conductivity, reaching 21.721 µS while preserving the essential oxygen functional groups. Furthermore, a biosensor was fabricated using wrinkled GO deposited via DEP force. The biosensor demonstrated superior sensitivity, exhibiting a 9.6-fold enhancement compared with reduced GO (rGO) biosensors, as demonstrated through biological experiments targeting inducible nitric oxide synthase. This study highlights the potential of using DEP force to enhance electrical conductivity in GO-based biosensing applications, opening new avenues for high-performance diagnostics.


Assuntos
Técnicas Biossensoriais , Grafite , Técnicas Biossensoriais/métodos , Oxirredução , Condutividade Elétrica , Grafite/química , Oxigênio
20.
Nat Neurosci ; 27(10): 1918-1933, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39187706

RESUMO

The accumulation of reactive oxygen species (ROS) is a common feature of tauopathies, defined by Tau accumulations in neurons and glia. High ROS in neurons causes lipid production and the export of toxic peroxidated lipids (LPOs). Glia uptake these LPOs and incorporate them into lipid droplets (LDs) for storage and catabolism. We found that overexpressing Tau in glia disrupts LDs in flies and rat neuron-astrocyte co-cultures, sensitizing the glia to toxic, neuronal LPOs. Using a new fly tau loss-of-function allele and RNA-mediated interference, we found that endogenous Tau is required for glial LD formation and protection against neuronal LPOs. Similarly, endogenous Tau is required in rat astrocytes and human oligodendrocyte-like cells for LD formation and the breakdown of LPOs. Behaviorally, flies lacking glial Tau have decreased lifespans and motor defects that are rescuable by administering the antioxidant N-acetylcysteine amide. Overall, this work provides insights into the important role that Tau has in glia to mitigate ROS in the brain.


Assuntos
Gotículas Lipídicas , Neuroglia , Neurônios , Estresse Oxidativo , Proteínas tau , Animais , Proteínas tau/metabolismo , Estresse Oxidativo/fisiologia , Neuroglia/metabolismo , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Ratos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Drosophila , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Técnicas de Cocultura , Células Cultivadas
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