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1.
Int J Sports Med ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38631375

RESUMEN

We compared the immediate response and recovery of femoral cartilage morphology following aerobic or resistance exercise to a control condition. Fifteen healthy young males (23.9 years; 170.1 cm; 69.7 kg) visited the laboratory three separate days and randomly performed one of the 30 min exercise aerobic exercise (treadmill running); resistance exercises (leg presses, back squats, and knee extensions); or seated rest as the control, each followed by the 50 min recovery. Ultrasonographic images of the femoral cartilage cross-sectional area (CSA) were obtained before and after exercise and every 5 min thereafter. To test exercise effects over time, a mixed model analysis of variance and Tukey-Kramer post-hoc tests were performed (p<0.05). The femoral cartilage CSA was different (condition × time: F34,742=4.30, p<0.0001) that the femoral cartilage CSA was decreased after the aerobic (-5.8%, p<0.0001) and the resistance (-3.4%, p=0.04) exercises, compared to the pre-exercise levels. Deformed femoral cartilage CSA took 35- and 10 min to return to the pre-exercise levels after aerobic and resistance exercises (p>0.09), respectively. Thirty minutes of moderate exertion performing aerobic or resistance exercises immediately reduced the femoral cartilage CSA. A rest period ranging from 10 to 35 min was required for cartilage recovery after weight-bearing exercises.

2.
Sci Rep ; 14(1): 7008, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38523148

RESUMEN

In the semiconductor manufacturing process, when conducting inductively coupled plasma-reactive ion etching in challenging environments, both wafers and the ceramic components comprising the chamber's interior can be influenced by plasma attack. When ceramic components are exposed to long-term plasma environments, the eroded components must be replaced. Furthermore, non-volatile reactants can form and settle on semiconductor chips, acting as contaminants and reducing semiconductor production yield. Therefore, for semiconductor processing equipment parts to be utilized, it is necessary that they exhibit minimized generation of contaminant particles and not deviate significantly from the composition of conventionally used Al2O3 and Y2O3; part must also last long in various physicochemical etching environment. Herein, we investigate the plasma etching behavior of Y2O3-Y4Al2O9 (YAM) composites with a variety of mixing ratios under different gas fraction conditions. The investigation revealed that the etching rates and changes in surface roughness for these materials were significantly less than those of Y2O3 materials subjected to both chemical and physical etching. Microstructure analysis was conducted to demonstrate the minimization of crater formation. Mechanical properties of the composite were also analyzed. The results show that the composite can be commercialized as next-generation ceramic component in semiconductor processing equipment applications.

3.
Int J Biol Macromol ; 254(Pt 2): 127876, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37926322

RESUMEN

The clinical utility of bone morphogenetic protein 2 (BMP2) is limited because of the poor attraction between BMP2 and carriers, resulting in low loading efficiency and initial burst release. Here, the high binding affinity of BMP2 to the biosilica surface was utilized to overcome this limitation. Atomic force microscopy revealed that BMP2 bound nearly 8- and 2-fold more strongly to biosilica-coated hydroxyapatite than to uncoated and plain silica-coated hydroxyapatite, respectively. To achieve controlled release, collagen was introduced between the silica layers on hydroxyapatite, which was optimized by adjusting the collagen concentration and number of layers. The optimal biosilica/collagen formulation induced sustained BMP2 release without compromising loading efficiency. BMP2 combined with the mentioned formulation led to an increase in osteogenesis, as compared to the combination of BMP2 with either biosilica-coated or non-coated hydroxyapatite in vitro. In rat calvarial defect models, the biosilica/collagen-coated hydroxyapatite with 1 µg BMP2 showed 26 % more bone regeneration than the same dose of BMP2-loaded hydroxyapatite and 10.6 % more than hydroxyapatite with 2.5-fold dose of BMP2. Using BMP2 affinity carriers coated with biosilica/collagen allows for more efficacious in situ loading and delivery of BMP2, making them suitable for the clinical application of growth factors through a soaking method.


Asunto(s)
Proteína Morfogenética Ósea 2 , Osteogénesis , Ratas , Animales , Proteína Morfogenética Ósea 2/farmacología , Proteína Morfogenética Ósea 2/metabolismo , Regeneración Ósea , Durapatita , Colágeno , Dióxido de Silicio , Andamios del Tejido
4.
Nano Converg ; 10(1): 55, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38038784

RESUMEN

HfO2 shows promise for emerging ferroelectric and resistive switching (RS) memory devices owing to its excellent electrical properties and compatibility with complementary metal oxide semiconductor technology based on mature fabrication processes such as atomic layer deposition. Oxygen vacancy (Vo), which is the most frequently observed intrinsic defect in HfO2-based films, determines the physical/electrical properties and device performance. Vo influences the polymorphism and the resulting ferroelectric properties of HfO2. Moreover, the switching speed and endurance of ferroelectric memories are strongly correlated to the Vo concentration and redistribution. They also strongly influence the device-to-device and cycle-to-cycle variability of integrated circuits based on ferroelectric memories. The concentration, migration, and agglomeration of Vo form the main mechanism behind the RS behavior observed in HfO2, suggesting that the device performance and reliability in terms of the operating voltage, switching speed, on/off ratio, analog conductance modulation, endurance, and retention are sensitive to Vo. Therefore, the mechanism of Vo formation and its effects on the chemical, physical, and electrical properties in ferroelectric and RS HfO2 should be understood. This study comprehensively reviews the literature on Vo in HfO2 from the formation and influencing mechanism to material properties and device performance. This review contributes to the synergetic advances of current knowledge and technology in emerging HfO2-based semiconductor devices.

5.
BMC Bioinformatics ; 24(1): 447, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38012571

RESUMEN

BACKGROUND: Aptamers, which are biomaterials comprised of single-stranded DNA/RNA that form tertiary structures, have significant potential as next-generation materials, particularly for drug discovery. The systematic evolution of ligands by exponential enrichment (SELEX) method is a critical in vitro technique employed to identify aptamers that bind specifically to target proteins. While advanced SELEX-based methods such as Cell- and HT-SELEX are available, they often encounter issues such as extended time consumption and suboptimal accuracy. Several In silico aptamer discovery methods have been proposed to address these challenges. These methods are specifically designed to predict aptamer-protein interaction (API) using benchmark datasets. However, these methods often fail to consider the physicochemical interactions between aptamers and proteins within tertiary structures. RESULTS: In this study, we propose AptaTrans, a pipeline for predicting API using deep learning techniques. AptaTrans uses transformer-based encoders to handle aptamer and protein sequences at the monomer level. Furthermore, pretrained encoders are utilized for the structural representation. After validation with a benchmark dataset, AptaTrans has been integrated into a comprehensive toolset. This pipeline synergistically combines with Apta-MCTS, a generative algorithm for recommending aptamer candidates. CONCLUSION: The results show that AptaTrans outperforms existing models for predicting API, and the efficacy of the AptaTrans pipeline has been confirmed through various experimental tools. We expect AptaTrans will enhance the cost-effectiveness and efficiency of SELEX in drug discovery. The source code and benchmark dataset for AptaTrans are available at https://github.com/pnumlb/AptaTrans .


Asunto(s)
Aptámeros de Nucleótidos , Aptámeros de Nucleótidos/química , Técnica SELEX de Producción de Aptámeros/métodos , Programas Informáticos , Redes Neurales de la Computación , Algoritmos , Ligandos
6.
Int J Mol Sci ; 24(21)2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37958885

RESUMEN

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.


Asunto(s)
Antioxidantes , Nanopartículas , Humanos , Antioxidantes/farmacología , Peróxido de Hidrógeno/farmacología , Estrés Oxidativo , Especies Reactivas de Oxígeno , Nanopartículas Magnéticas de Óxido de Hierro , Nanopartículas/química , Compuestos Férricos/farmacología , Compuestos Férricos/química
7.
Neural Netw ; 167: 266-282, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37666185

RESUMEN

Adversarial robustness is considered a required property of deep neural networks. In this study, we discover that adversarially trained models might have significantly different characteristics in terms of margin and smoothness, even though they show similar robustness. Inspired by the observation, we investigate the effect of different regularizers and discover the negative effect of the smoothness regularizer on maximizing the margin. Based on the analyses, we propose a new method called bridged adversarial training that mitigates the negative effect by bridging the gap between clean and adversarial examples. We provide theoretical and empirical evidence that the proposed method provides stable and better robustness, especially for large perturbations.


Asunto(s)
Redes Neurales de la Computación
8.
J Extracell Vesicles ; 12(8): e12357, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37563797

RESUMEN

Despite the capability of extracellular vesicles (EVs) derived from Gram-negative and Gram-positive bacteria to induce potent anti-tumour responses, large-scale production of bacterial EVs remains as a hurdle for their development as novel cancer immunotherapeutic agents. Here, we developed manufacturing processes for mass production of Escherichia coli EVs, namely, outer membrane vesicles (OMVs). By combining metal precipitation and size-exclusion chromatography, we isolated 357 mg in total protein amount of E. coli OMVs, which was equivalent to 3.93 × 1015 particles (1.10 × 1010 particles/µg in total protein amounts of OMVs) from 160 L of the conditioned medium. We show that these mass-produced E. coli OMVs led to complete remission of two mouse syngeneic tumour models. Further analysis of tumour microenvironment in neoantigen-expressing tumour models revealed that E. coli OMV treatment causes increased infiltration and activation of CD8+ T cells, especially those of cancer antigen-specific CD8+ T cells with high expression of TCF-1 and PD-1. Furthermore, E. coli OMVs showed synergistic anti-tumour activity with anti-PD-1 antibody immunotherapy, inducing substantial tumour growth inhibition and infiltration of activated cancer antigen-specific stem-like CD8+ T cells into the tumour microenvironment. These data highlight the potent anti-tumour activities of mass-produced E. coli OMVs as a novel candidate for developing next-generation cancer immunotherapeutic agents.


Asunto(s)
Vesículas Extracelulares , Neoplasias , Animales , Ratones , Escherichia coli/metabolismo , Vesículas Extracelulares/química , Membrana Externa Bacteriana/metabolismo , Linfocitos T CD8-positivos , Inmunoterapia , Neoplasias/terapia , Neoplasias/metabolismo
9.
Biotechnol J ; 18(11): e2300060, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37478121

RESUMEN

Certain cancers, such as triple-negative breast cancer (TNBC), pose a challenging prognosis due to the absence of identifiable hormone-related receptors and effective targeted therapies. Consequently, novel therapeutics are required for these cancers, offering minimal side effects and reduced drug resistance. Unexpectedly, siRNA-7, initially employed as a control, exhibited significant efficacy in inhibiting cell viability in MDA-MB-231 cells. Through a genome-wide search of seed sequences, the targets of siRNA-7 were identified as cancer-related genes, namely PRKCE, RBPJ, ZNF737, and CDC7 in MDA-MB-231 cells. The mRNA repression analysis confirmed the simultaneous suppression by siRNA-7. Combinatorial administration of single-targeting siRNAs demonstrated a comparable reduction in viability to that achieved by siRNA-7. Importantly, siRNA-7 selectively inhibited cell viability in MDA-MB-231 cells, while normal HDF-n cells remained unaffected. Furthermore, in a xenograft mouse model, siRNA-7 exhibited a remarkable 76% reduction in tumor volume without any loss in body weight. These findings position siRNA-7 as a promising candidate for a novel, safe, specific, and potent TNBC cancer therapeutic. Moreover, the strategy of multiple suppressing small interfering RNA holds potential for the treatment of various diseases associated with gene overexpression.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Humanos , Animales , Ratones , ARN Interferente Pequeño/genética , Neoplasias de la Mama Triple Negativas/terapia , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Apoptosis , Proteínas Serina-Treonina Quinasas/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/farmacología , Proteínas de Ciclo Celular/uso terapéutico
10.
Biotechnol J ; 18(8): e2200517, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37201948

RESUMEN

A rapid hemostatic sealant can save a patient's life from shock and death due to severe trauma or excessive bleeding from the wound site during surgery. However, an ideal hemostatic sealant needs to meet the standards of safety, efficacy, usability, cost, and approvability and overcome new challenges. Here, we devised a combinatorial hemostatic sealant of PEG succinimidyl glutarate-based cross-linking branched polymers (CBPs) and the active hemostatic peptide (AHP). After ex vivo optimization, the best hemostatic combination was called an active cross-linking hemostatic sealant (ACHS). Interestingly, ACHS formed cross-links with serum proteins, blood cells, and tissue and interconnected coating on blood cells, which might induce hemostasis and tissue adhesion based on SEM images. Moreover, ACHS showed the highest coagulation efficacy, formation, and agglomeration of thrombi within 12 s, and in vitro biocompatibility. Mouse model experiments represented rapid hemostasis within 1 min, wound closure of the liver incision, and less bleeding than the commercialized sealant with tissue biocompatibility. ACHS has the advantages of rapid hemostasis, mild sealant, and easy supply by chemical synthesis without inhibition by anticoagulants, which might minimize bacterial infection by immediate wound closure. Therefore, ACHS could become a new-type hemostatic sealant to match surgical needs for internal bleeding.


Asunto(s)
Hemostáticos , Ratones , Animales , Hemostáticos/farmacología , Hemostasis , Hemorragia/terapia , Hígado
11.
Biomed Eng Lett ; 13(2): 209-219, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37124115

RESUMEN

Heating nanoparticles with a magnetic field could facilitate selective remote control of neural activity in deep tissue. However, current magnetothermal stimulation approaches are limited to single-channel stimulation. Here, we investigated various designs for multichannel magnetothermal stimulation based on an array of resonant coils that are driven by a single loop coil. Using a tuning capacitor that allows resonant coils to resonate at the operating frequency, each coil's ON and OFF resonance can be controlled, enabling us to select stimulation channels. We found that smaller inner diameters of resonant coils produce more localized magnetic fields while larger coils produce magnetic fields over a longer distance. The constructed multichannel resonant coil arrays can provide a high enough magnetic field intensity to raise the temperature of nanoparticles by 8 °C when we apply 35.2 W into the loop coil that is spaced 1 mm from the target neurons. This multichannel stimulation using a simple resonant circuit approach would be useful for clinical applications of magnetothermal neural stimulation.

12.
Materials (Basel) ; 16(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37049141

RESUMEN

The punching process of AHSS induces edge cracks in successive process, limiting the application of AHSS for vehicle bodies. Controlling and predicting edge quality is substantially difficult due to the large variation in edge quality, die wear induced by high strength, and the complex effect of phase distribution. To overcome this challenge, a quality prediction model that considers the variation of the entire edge should be developed. In this study, the image of the entire edge was analyzed to provide a comprehensive evaluation of its quality. Statistical features were extracted from the edge images to represent the edge quality of DP780, DP980, and MART1500 steels. Combined with punching monitoring signals, a prediction model for hole expansion ratio was developed under punch conditions of varying clearance, punch angle, and punch edge radius. It was found that the features of grayscale variation are affected by the punching conditions and are related to the double burnish and uneven burr, which degrades the edge quality. Prediction of HER was possible based on only edge image and monitoring signals, with the same performance as the prediction based solely on punching parameters and material properties. The prediction performance improved when using all the features.

13.
West J Emerg Med ; 24(2): 279-286, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36976593

RESUMEN

INTRODUCTION: Neuroimaging is recommended for patients with seizures to identify intracranial pathology. However, emergency physicians should consider the risks and benefits of neuroimaging in pediatric patients because of their need for sedation and greater sensitivity to radiation than adults. The purpose of this study was to identify associated factors of neuroimaging abnormalities in pediatric patients experiencing their first afebrile seizure. METHODS: This was a retrospective, multicenter study that included children who presented to the emergency departments (ED) of three hospitals due to afebrile seizures between January 2018-December 2020. We excluded children with a history of seizure or acute trauma and those with incomplete medical records. A single protocol was followed in the three EDs for all pediatric patients experiencing their first afebrile seizure. We performed multivariable logistic regression analysis to identify factors associated with neuroimaging abnormalities. RESULTS: In total, 323 pediatric patients fulfilled the study criteria, and neuroimaging abnormalities were observed in 95 patients (29.4%). Multivariable logistic regression analysis showed that Todd's paralysis (odds ratio [OR] 3.72, 95% confidence interval [CI] 1.03-13.36; P=0.04), absence of poor oral intake (POI) (OR 0.21, 95% CI 0.05-0.98; P=0.05), lactic acidosis (OR 1.16, 95% CI 1.04-1.30; P=0.01), and higher level of bilirubin (OR 3.33, 95% CI 1.11-9.95; P=0.03) were significantly associated with neuroimaging abnormalities. Based on these results, we constructed a nomogram to predict the probability of brain imaging abnormalities. CONCLUSION: Todd's paralysis, absence of POI, and higher levels of lactic acid and bilirubin were associated factors of neuroimaging abnormalities in pediatric patients with afebrile seizure.


Asunto(s)
Neuroimagen , Convulsiones , Adulto , Niño , Humanos , Lactante , Estudios Retrospectivos , Convulsiones/complicaciones , Parálisis/complicaciones , Servicio de Urgencia en Hospital
14.
Nanotechnology ; 34(20)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36745914

RESUMEN

HfO2-based ferroelectric thin films have attracted significant interest for semiconductor device applications due to their compatibility with complementary metal oxide semiconductor (CMOS) technology. One of the benefits of HfO2-based ferroelectric thin films is their ability to be scaled to thicknesses as low as 10 nm while retaining their ferroelectric properties; a feat that has been difficult to accomplish with conventional perovskite-based ferroelectrics using CMOS-compatible processes. However, reducing the thickness limit of HfO2-based ferroelectric thin films below the sub 5 nm thickness regime while preserving their ferroelectric property remains a formidable challenge. This is because both the structural factors of HfO2, including polymorphism and orientation, and the electrical factors of HfO2-based devices, such as the depolarization field, are known to be highly dependent on the HfO2thickness. Accordingly, when the thickness of HfO2drops below 5 nm, these factors will become even more crucial. In this regard, the size effect of HfO2-based ferroelectric thin films is thoroughly discussed in the present review. The impact of thickness on the ferroelectric property of HfO2-based thin films and the electrical performance of HfO2-based ferroelectric semiconductor devices, such as ferroelectric random-access-memory, ferroelectric field-effect-transistor, and ferroelectric tunnel junction, is extensively discussed from the perspective of fundamental theory and experimental results. Finally, recent developments and reports on achieving ferroelectric HfO2at sub-5 nm thickness regime and their applications are discussed.

15.
Materials (Basel) ; 16(3)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36770047

RESUMEN

Recent advances in additive manufacturing have provided more freedom in the design of metal parts; hence, the prototyping of fluid machines featuring extremely complex geometries has been investigated extensively. The fabrication of fluid machines via additive manufacturing requires significant attention to part stability; however, studies that predict regions with a high risk of collapse are few. Therefore, a novel algorithm that can detect collapse regions precisely is proposed herein. The algorithm reflects the support span over the faceted surface via propagation and invalidates overestimated collapse regions based on the overhang angle. A heat exchanger model with an extremely complex internal space is adopted to validate the algorithm. Three samples from the model are extracted and their prototypes are fabricated via laser powder bed fusion. The results yielded by the fabricated samples and algorithm with respect to the sample domain are compared. Regions of visible collapse identified on the surface of the fabricated samples are predicted precisely by the algorithm. Thus, the supporting span reflected by the algorithm provides an extremely precise prediction of collapse.

16.
J Appl Psychol ; 108(8): 1391-1407, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36757954

RESUMEN

Drawing from the neuroscience literature and recent advancements in sleep technology, we examine how closed loop acoustic stimulation can improve employee sleep and subsequent work behaviors. Specifically, we hypothesize that because closed loop acoustic stimulation improves sleep quality, it enhances work engagement, task performance, and organizational citizenship behavior (OCB) and lowers counterproductive workplace behavior. In a 4-week within-subjects field experiment, 81 employees wore headbands during sleep hours in active mode (with closed loop acoustic stimulation) or sham mode with the volume off (control condition). We found that the treatment condition was linked to higher work engagement, task performance, and OCB the next day (but not counterproductive workplace behavior). Additionally, we found that the headbands were more effective for younger employees. This study contributes to the literature on sleep and work by highlighting a cost-efficient intervention for improving sleep and sleep-related outcomes which do not rely on surmounting the difficulties entailed in increasing sleep duration, as well as age as a boundary condition limiting the effects. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Calidad del Sueño , Dispositivos Electrónicos Vestibles , Humanos , Estimulación Acústica , Lugar de Trabajo , Sueño/fisiología
17.
IEEE Trans Pattern Anal Mach Intell ; 45(2): 2645-2651, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35446760

RESUMEN

Deep learning is vulnerable to adversarial examples. Many defenses based on randomized neural networks have been proposed to solve the problem, but fail to achieve robustness against attacks using proxy gradients such as the Expectation over Transformation (EOT) attack. We investigate the effect of the adversarial attacks using proxy gradients on randomized neural networks and demonstrate that it highly relies on the directional distribution of the loss gradients of the randomized neural network. We show in particular that proxy gradients are less effective when the gradients are more scattered. To this end, we propose Gradient Diversity (GradDiv) regularizations that minimize the concentration of the gradients to build a robust randomized neural network. Our experiments on MNIST, CIFAR10, and STL10 show that our proposed GradDiv regularizations improve the adversarial robustness of randomized neural networks against a variety of state-of-the-art attack methods. Moreover, our method efficiently reduces the transferability among sample models of randomized neural networks.

18.
Int J Mol Sci ; 23(23)2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36498831

RESUMEN

The primary cilium (PC) is a microtubule-based antenna-like organelle projecting from the surface of the cell membrane. We previously reported that PC formation could be regulated by nephronophthisis 3 (NPHP3) expression followed by its interaction with thymosin ß4. Here, we investigated whether cancer cell viability is regulated by NPHP3-mediated PC formation. The total and viable cell number were reduced by incubating cells under serum deprivation (SD) without fetal bovine serum (-FBS). PC frequency was increased by SD which enhanced NPHP3 expression and hypoxia inducible factor (HIF)-1α. The role of HIF-1α on NPHP3 expression and PC formation was confirmed by the binding of HIF-1α to the NPHP3 promoter and siRNA-based inhibition of HIF-1α (siHIF-1α), respectively. HIF-1α-stabilizing dimethyloxallyl glycine (DMOG) and hypoxic conditions increased NPHP3 expression and PC formation. In addition, as SD elevated the reactive oxygen species (ROS), PC frequency and NPHP3 expression were inhibited by a treatment with N-acetylcysteine (NAC), a ROS scavenger. PC formation was increased by H2O2 treatment, which was inhibited by siHIF-1α. The inhibition of ERK with P98059 decreased the frequency of PC formation and NPHP3 expression. Cell viability was reduced by a treatment with ciliobrevin A (CilioA) to inhibit PC formation, which was re-affirmed by using PC-deficient IFT88-/- cells. Taken together, the results imply that PC formation in cancer cells could be controlled by NPHP3 expression through ROS-induced HIF-1α and ERK activation under SD conditions. It suggests that cancer cell viability under SD conditions could be maintained by NPHP3 expression to regulate PC formation.


Asunto(s)
Cilios , Subunidad alfa del Factor 1 Inducible por Hipoxia , Cinesinas , Femenino , Humanos , Hipoxia de la Célula , Cilios/metabolismo , Células HeLa , Peróxido de Hidrógeno/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Cinesinas/genética , Cinesinas/metabolismo
19.
Sci Rep ; 12(1): 20170, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36424462

RESUMEN

We investigated the function of thymosin beta-4 (TB4) expression and primary cilium (PC) formation via the underlying Nrf2-dependent mechanism for cervical cancer cell (CC) survival under conditions of serum deprivation (SD). TB4 silencing was achieved using RNA interference. The percentage of PC formation was analyzed by immunofluorescence staining. Nrf2 expression was modified by the preparation of stable Nrf2-knockdown cells with shNrf2 and the overexpression of Nrf2 with pcDNA-Nrf2 plasmids. Gene expression was measured using reverse-transcription PCR, Gaussia luciferase assay, and western blotting. Cell viability was assessed using the MTT assay or CellTiter Glo assay. Reactive oxygen species (ROS) were detected with flow cytometry. CCs incubated in SD without fetal bovine serum remained viable, and SD increased PC formation and TB4 transcription. CC viability was further decreased by treatment with ciliobrevin A to inhibit PC formation or TB4-siRNA. SD increased ROS, including H2O2. N-acetylcysteine inhibited ROS production following H2O2 treatment or SD, which also decreased PC formation and TB4 transcription. Meanwhile, H2O2 increased PC formation, which was attenuated in response to TB4 siRNA. Treatment with H2O2 increased Nrf2 expression, antioxidant responsive element (ARE) activity, and PC formation, which were inhibited by the Nrf2 inhibitor clobestasol propionate. Nrf2 knockdown via expression of Tet-On shNrf2 enhanced ROS production, leading to increased PC formation and decreased TB4 expression; these effects were counteracted by Nrf2 overexpression. Our data demonstrate that Nrf2 counter-regulates TB4 expression and PC formation for CC survival under conditions of SD, suggesting cervical CC survival could be upregulated by PC formation via Nrf2 activation and TB4 expression.


Asunto(s)
Factor 2 Relacionado con NF-E2 , Timosina , Humanos , Supervivencia Celular/genética , Cilios/metabolismo , Peróxido de Hidrógeno/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , ARN Interferente Pequeño/metabolismo , Células HeLa , Timosina/metabolismo
20.
Int J Mol Sci ; 23(17)2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-36077015

RESUMEN

Multi-functionalized carbon nanomaterials have attracted interest owing to their excellent synergic properties, such as plasmon resonance energy transfer and surface-enhanced Raman scattering. Particularly, nanoparticle (NP)-decorated graphene (GRP) has been applied in various fields. In this study, silver NP (AgNP)- and magnetic iron oxide NP (IONP)-decorated GRP were prepared and utilized as biosensing platforms. In this case, AgNPs and GRP exhibit plasmonic properties, whereas IONPs exhibit magnetic properties; therefore, this hybrid nanomaterial could function as a magnetoplasmonic substrate for the magnetofluoro-immunosensing (MFI) system. Conversely, exosomes were recently considered high-potential biomarkers for the diagnosis of diseases. However, exosome diagnostic use requires complex isolation and purification methods. Nevertheless, we successfully detected a prostate-cancer-cell-derived exosome (PC-exosome) from non-purified exosomes in a culture media sample using Ag/IO-GRP and dye-tetraspanin antibodies (Ab). First, the anti-prostate-specific antigen was immobilized on the Ag/IO-GRP and it could isolate the PC-exosome from the sample via an external magnetic force. Dye-tetraspanin Ab was added to the sample to induce the sandwich structure. Based on the number of exosomes, the fluorescence intensity from the dye varied and the system exhibited highly sensitive and selective performance. Consequently, these hybrid materials exhibited excellent potential for biosensing platforms.


Asunto(s)
Técnicas Biosensibles , Exosomas , Grafito , Nanopartículas , Neoplasias , Técnicas Biosensibles/métodos , Oro/química , Grafito/química , Humanos , Masculino , Nanopartículas/química
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