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1.
Radiology ; 302(1): 187-197, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34636634

RESUMEN

Background Evaluation of interstitial lung disease (ILD) at CT is a challenging task that requires experience and is subject to substantial interreader variability. Purpose To investigate whether a proposed content-based image retrieval (CBIR) of similar chest CT images by using deep learning can aid in the diagnosis of ILD by readers with different levels of experience. Materials and Methods This retrospective study included patients with confirmed ILD after multidisciplinary discussion and available CT images identified between January 2000 and December 2015. Database was composed of four disease classes: usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia, and chronic hypersensitivity pneumonitis. Eighty patients were selected as queries from the database. The proposed CBIR retrieved the top three similar CT images with diagnosis from the database by comparing the extent and distribution of different regional disease patterns quantified by a deep learning algorithm. Eight readers with varying experience interpreted the query CT images and provided their most probable diagnosis in two reading sessions 2 weeks apart, before and after applying CBIR. Diagnostic accuracy was analyzed by using McNemar test and generalized estimating equation, and interreader agreement was analyzed by using Fleiss κ. Results A total of 288 patients were included (mean age, 58 years ± 11 [standard deviation]; 145 women). After applying CBIR, the overall diagnostic accuracy improved in all readers (before CBIR, 46.1% [95% CI: 37.1, 55.3]; after CBIR, 60.9% [95% CI: 51.8, 69.3]; P < .001). In terms of disease category, the diagnostic accuracy improved after applying CBIR in UIP (before vs after CBIR, 52.4% vs 72.8%, respectively; P < .001) and NSIP cases (before vs after CBIR, 42.9% vs 61.6%, respectively; P < .001). Interreader agreement improved after CBIR (before vs after CBIR Fleiss κ, 0.32 vs 0.47, respectively; P = .005). Conclusion The proposed content-based image retrieval system for chest CT images with deep learning improved the diagnostic accuracy of interstitial lung disease and interreader agreement in readers with different levels of experience. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Wielpütz in this issue.


Asunto(s)
Aprendizaje Profundo , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Diagnóstico Diferencial , Femenino , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos
2.
Int J Mol Sci ; 23(24)2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36555388

RESUMEN

Chrysin is a flavonoid found abundantly in substances, such as honey and phytochemicals, and is known to exhibit anticancer effects against various cancer cells. Nevertheless, the anticancer effect of chrysin against oral cancer has not yet been verified. Furthermore, the mechanism underlying autophagy is yet to be clearly elucidated. Thus, this study investigated chrysin-mediated apoptosis and autophagy in human mucoepidermoid carcinoma (MC-3) cells. The change in MC-3 cell viability was examined using a 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide cell viability assay, as well as 40,6-diamidino-2-phenylindole, annexin V, and propidium iodide staining. Western blotting was used to analyze the proteins related to apoptosis and the mitogen-activated protein kinase (MAPK) pathway. In addition, the presence or absence of autophagy and changes in the expression of related proteins were investigated using acridine orange staining and Western blot. The results suggested that chrysin induced apoptosis and autophagy in MC-3 oral cancer cells via the MAPK/extracellular signal-regulated kinase pathway. Moreover, the induced autophagy exerted a cytoprotective effect against apoptosis. Thus, the further reduced cell viability due to autophagy as well as apoptosis induction highlight therapeutic potential of chrysin for oral cancer.


Asunto(s)
Apoptosis , Neoplasias de la Boca , Humanos , Serina-Treonina Quinasas TOR/metabolismo , Flavonoides/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Autofagia , Línea Celular Tumoral , Neoplasias de la Boca/tratamiento farmacológico
3.
Med Sci Monit ; 24: 5271-5278, 2018 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-30056459

RESUMEN

BACKGROUND Physical changes due to aging lead to weakening of respiratory muscles and decreased lung functions that result in increasing risk of chronic respiratory disease. A complex respiratory rehabilitation program is needed to prevent respiratory diseases and improve lung functions and quality of life. The purpose of the present study was to examine the effects of respiratory training programs on pulmonary functions, cardiovascular endurance, and quality of life in elderly women. MATERIAL AND METHODS The program was structured with respiration exercise and playing wind musical instruments for 10 weeks (n=13) and 5 weeks (n=16), respectively, for elderly women in 2 different community welfare centers. The program consisted of breathing exercises twice a week, 20 min per session, and 40 min of wind instrumentation. Effects were assessed using forced vital capacity (FVC), forced expiratory volume-one second (FEV1), FEV1/FVC ratio (FEV1%), maximum voluntary ventilation (MVV), 6-minute walk test (6MWT), modified Borg scale (MBS), and life satisfaction scale (LSS). RESULTS The 10-week program group (10WPG) showed significant differences in FVC, MVV, 6MWT, MBS, and LSS before and after interventions (p<.05), and the 5-week program group (5WPG) showed significant differences in FVC and 6MWT. MVV, MBS, and LSS were not significantly different between the 2 groups (p<.05). CONCLUSIONS This study confirms that the long-term respiration training program has positive effects on pulmonary functions, cardiopulmonary endurance, and quality of life. Various respiratory training programs and long-term implementations are needed to prevent respiratory illness and to improve lung functions and quality of life of respiratory patients.


Asunto(s)
Ejercicios Respiratorios/instrumentación , Ejercicios Respiratorios/métodos , Anciano , Prueba de Esfuerzo/métodos , Tolerancia al Ejercicio/fisiología , Femenino , Volumen Espiratorio Forzado , Humanos , Pulmón/fisiopatología , Ventilación Voluntaria Máxima , Persona de Mediana Edad , Calidad de Vida , Respiración , Pruebas de Función Respiratoria/métodos , Músculos Respiratorios/fisiopatología , Capacidad Vital
4.
Environ Sci Technol ; 49(10): 6045-50, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25893445

RESUMEN

Many studies have focused on desalination via hydrate formation; however, for their potential application, knowledge pertaining to thermodynamic stability, formation kinetics, and guest occupation behavior in clathrate hydrates needs to be determined. Herein, the phase equilibria of SF6 hydrates in the presence of NaCl solutions (0, 2, 4, and 10 wt %) were monitored in the temperature range of 277-286 K and under pressures of up to 1.4 MPa. The formation kinetics of SF6 hydrates in the presence of NaCl solutions (0, 2, and 4 wt %) was also investigated. Gas consumption curves of SF6 hydrates showed that a pure SF6 hydrate system allowed fast hydrate growth as well as high conversion yield, whereas SF6 hydrate in the presence of NaCl solutions showed retarded hydrate growth rate as well as low conversion yield. In addition, structural identification of SF6 hydrates with and without NaCl solutions was performed using spectroscopic tools such as Raman spectroscopy and X-ray diffraction. The Raman spectrometer was also used to evaluate the temperature-dependent release behavior of guest molecules in SF6 and SF6 + 4 wt % NaCl hydrates. The results indicate that whereas SF6 hydrate starts to decompose at around 240 K, the escape of SF6 molecules in SF6 + 4 wt % NaCl hydrate is initiated rapidly at around 205 K. The results of this study can provide a better understanding of guest-host interaction in electrolyte-containing systems.


Asunto(s)
Gases/química , Cloruro de Sodio/química , Hexafluoruro de Azufre/química , Restauración y Remediación Ambiental , Cinética , Espectrometría Raman , Termodinámica , Purificación del Agua , Difracción de Rayos X
5.
Healthcare (Basel) ; 12(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38470618

RESUMEN

A spirometer is a medical device frequently used clinically for the diagnosis and prediction of lung disease. This study aimed to investigate the clinical usefulness of a hand-held spirometer (The Spirokit), compared with conventional spirometry in patients with chronic obstructive pulmonary disease (COPD). This study was conducted from February 2022 to October 2022. Measurements from 80 patients with COPD (male: 53, female: 27) were obtained using The Spirokit and PC-based pulmonary function test equipment, and the resulting values were compared and analyzed. For the concurrent validity comparison of The Spirokit, the intra-class correlation (ICC 2, 1), coefficients of variation (CVME), 95% limits of agreement (95% LOA), and Cohen's Kappa Index were analyzed. The Spirokit showed high agreement (ICC: 0.929-0.989; 95% LOA: -0.525 to 2.559; and CVME: 0.05-0.08) with the PC-based pulmonary function tester. Using the Cohen's kappa coefficients, the device showed high sensitivity, specificity, and accuracy scores of Pa: 0.90, Pc: 0.52, and K: 0.79, respectively, indicating considerable agreement. The Spirokit, a portable pulmonary function test device, is a piece of equipment with high validity and portability, with high potential for replacing PC-based pulmonary function test equipment.

6.
Anticancer Res ; 44(7): 2961-2972, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38925830

RESUMEN

BACKGROUND/AIM: Kaempferol, a natural flavonoid, occurs abundantly in fruits and vegetables. It has various bioactivities, with antioxidant, anti-inflammatory, and other beneficial properties. The aim of this study was to investigate the in vitro effects of kaempferol on the proliferation, apoptosis, and autophagy of KB cells, a human cervical cancer cell line, and the corresponding action mechanisms. MATERIALS AND METHODS: The inhibitory efficacy of kaempferol on KB cervical cancer cells was investigated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, migration assay, 4',6-diamidino-2-phenylindole staining, flow cytometry, acridine orange staining and western blotting. RESULTS: Kaempferol reduced KB cell viability and migration in a dose-dependent manner. Additionally, kaempferol-induced apoptosis was confirmed, and kaempferol treatment influenced levels of apoptotic proteins. Autophagy was detected upon visualization of characteristic autophagic vacuoles and acidic vesicular organelles, and verified using western blotting, which revealed elevated levels of autophagy-related proteins. Kaempferol-mediated apoptosis and autophagy were evidently attributable to reduced phosphorylation in the phosphoinositide 3-kinase (PI3K)/serine/threonine kinase 1 (AKT)/mammalian target of rapamycin (mTOR) pathway. This finding was validated using a pharmacological inhibition assay with the PI3K pathway inhibitor LY294002, which promoted KB cell apoptosis and autophagy. CONCLUSION: Our results suggest that kaempferol induces apoptosis and autophagy by inhibiting the PI3K/AKT/mTOR pathway in human cervical cancer cells, empirically showing the anticancer effects of kaempferol, and thereby presenting it as a potential anticancer therapeutic agent.


Asunto(s)
Apoptosis , Autofagia , Quempferoles , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Neoplasias del Cuello Uterino , Humanos , Quempferoles/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Autofagia/efectos de los fármacos , Apoptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Femenino , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos
7.
Biomed Pharmacother ; 172: 116216, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38295755

RESUMEN

Platycodin D (PD) is the main component of triterpene saponins found in Platycodi radix. In this study, we observed a decrease in cell viability, an increase in apoptotic bodies, and an increase in the rate of apoptosis. Also, we observed an increase in cleaved PARP and Bax, a decrease in Bcl-2, and p-ERK, and an increase in p-p38 and p-JNK. Furthermore, a change in cell viability and the expression of p-p38, Bax, and Bcl-2 using the p38 inhibitor revealed a decrease in p-p38 and Bax and an increase in Bcl-2 in the inhibitor treatment group. In addition, we observed an increase in vacuole formation through morphological changes and an increase in acidic vesicular organelles (AVOs). We also observed an increase in the expression of beclin 1, LC 3-I, and -II. There was no significant decrease in cell viability in the group treated with 3-MA, but a decrease in cell viability was noted in the group treated with HCQ. HCQ treatment resulted in an increase in Bax and a decrease in Bcl-2. These findings reveal that in HT-29 colon cancer cells, PD induces apoptosis through the MAPK pathway, thereby exerting anticancer effects. Moreover, autophagy caused by PD inhibits apoptosis by protecting the cells.


Asunto(s)
Neoplasias del Colon , Saponinas , Triterpenos , Humanos , Proteína X Asociada a bcl-2 , Saponinas/farmacología , Triterpenos/farmacología , Apoptosis , Autofagia , Neoplasias del Colon/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-2
8.
Sci Rep ; 14(1): 4587, 2024 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-38403628

RESUMEN

The aim of our study was to assess the performance of content-based image retrieval (CBIR) for similar chest computed tomography (CT) in obstructive lung disease. This retrospective study included patients with obstructive lung disease who underwent volumetric chest CT scans. The CBIR database included 600 chest CT scans from 541 patients. To assess the system performance, follow-up chest CT scans of 50 patients were evaluated as query cases, which showed the stability of the CT findings between baseline and follow-up chest CT, as confirmed by thoracic radiologists. The CBIR system retrieved the top five similar CT scans for each query case from the database by quantifying and comparing emphysema extent and size, airway wall thickness, and peripheral pulmonary vasculatures in descending order from the database. The rates of retrieval of the same pairs of query CT scans in the top 1-5 retrievals were assessed. Two expert chest radiologists evaluated the visual similarities between the query and retrieved CT scans using a five-point scale grading system. The rates of retrieving the same pairs of query CTs were 60.0% (30/50) and 68.0% (34/50) for top-three and top-five retrievals. Radiologists rated 64.8% (95% confidence interval 58.8-70.4) of the retrieved CT scans with a visual similarity score of four or five and at least one case scored five points in 74% (74/100) of all query cases. The proposed CBIR system for obstructive lung disease integrating quantitative CT measures demonstrated potential for retrieving chest CT scans with similar imaging phenotypes. Further refinement and validation in this field would be valuable.


Asunto(s)
Enfisema Pulmonar , Tomografía Computarizada por Rayos X , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada de Haz Cónico , Radiólogos
9.
Rheumatology (Oxford) ; 52(9): 1583-91, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23685361

RESUMEN

OBJECTIVE: Emodin (3-methyl-1,6,8-trihydroxyanthraquinone) is one of the active components present in the root and rhizome of Rheum palmatum. It has been shown to contain biological activity (antitumour, antibacterial, diuretic and vasorelaxant effects). However, the mechanisms underlying the anti-arthritic effect of emodin have not been elucidated. Here we investigated whether emodin treatment would modulate the severity of the disease in an experimental arthritis model. METHODS: We evaluated the effects of emodin on CIA mice in vivo. RESULTS: The pathological processes of RA are mediated by a number of cytokines and MMPs. Expression of these proinflammatory mediators is controlled by nuclear factor-κB (NF-κB). This study was performed to explore the effect of emodin on control of the NF-κB activation pathway and to investigate whether emodin has anti-inflammatory effects in CIA mice in vivo. Emodin inhibited the nuclear translocation and DNA binding of NF-κB subunits, which were correlated with its inhibitory effect on cytoplasmic IκBα degradation in CIA mice. These events further suppressed chemokine production and MMP expression. In addition, emodin inhibited the osteoclast differentiation induced by M-CSF and receptor activation of NF-κB ligand in bone marrow macrophages. CONCLUSION: These findings suggest that emodin exerts anti-inflammatory effects in CIA mice through inhibition of the NF-κB pathway and therefore may have therapeutic value for the treatment of RA.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Emodina/uso terapéutico , Inflamación/tratamiento farmacológico , Articulaciones/efectos de los fármacos , Inhibidores de Proteínas Quinasas/uso terapéutico , Animales , Artritis Experimental/metabolismo , Artritis Experimental/patología , Emodina/farmacología , Articulaciones/metabolismo , Articulaciones/patología , Masculino , Ratones , Ratones Endogámicos DBA , Ratones Endogámicos ICR , FN-kappa B/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Subunidades de Proteína/metabolismo , Transporte de Proteínas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patología
10.
Biochim Biophys Acta Rev Cancer ; 1878(6): 188988, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37726064

RESUMEN

The Warburg effect is a phenomenon in which cancer cells rely primarily on glycolysis rather than oxidative phosphorylation, even in the presence of oxygen. Although evidence of its involvement in cell proliferation has been discovered, the advantages of the Warburg effect in cancer cell survival under treatment have not been fully elucidated. In recent years, the metabolic characteristics of radioresistant cancer cells have been evaluated, enabling an extension of the original concept of the Warburg effect. In this review, we focused on the role of the Warburg effect in redox homeostasis and DNA damage repair, two critical factors contributing to radioresistance. In addition, we highlighted the metabolic involvement in the radioresistance of cancer stem cells, which is the root cause of tumor recurrence. Finally, we summarized radiosensitizing drugs that target the Warburg effect. Insights into the molecular mechanisms underlying the Warburg effect and radioresistance can provide valuable information for developing strategies to enhance the efficacy of radiotherapy and provide future directions for successful cancer therapy.


Asunto(s)
Neoplasias , Fármacos Sensibilizantes a Radiaciones , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/radioterapia , Glucólisis , Fosforilación Oxidativa , Oxígeno/metabolismo
11.
Healthcare (Basel) ; 11(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37108008

RESUMEN

BACKGROUND: We aimed to investigate the effects of a community-based senior musical program on the cognitive and physical functions in older women. METHOD: Older women aged ≥65 years participating in a program at a community welfare center were randomized to experimental (n = 17) or control (n = 17) groups. The control group participated in singing and yoga classes offered at the welfare center, while the experimental group participated in a senior musical program consisting of vocal training, dancing, and breathing training. The effects of the 12-week program (120 min/session, two sessions/week) and the intergroup differences in outcomes were compared using the cognitive impairment screening test (CIST), pulmonary function test (PFT), respiratory muscle pressure test (RPT), and static and dynamic balance tests. RESULT: The experimental group showed significant post-intervention changes in CIST scores, cardiorespiratory parameters, and static and dynamic balance (p < 0.05), but the control group only showed significant changes in some respiratory and balance parameters (p < 0.05). In comparison with the control group, the experimental group showed significantly greater post-intervention changes in the CIST score, PFT and RPT parameters, static balance, and Y-balance anterior (p < 0.05). CONCLUSIONS: The senior musical program enhanced older women's cognitive, respiratory, and physical functions and promoted a sense of accomplishment and self-satisfaction.

12.
Cell Rep Med ; 4(1): 100880, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36603576

RESUMEN

Glioblastoma (GBM) currently has a dismal prognosis. GBM cells that survive radiotherapy contribute to tumor progression and recurrence with metabolic advantages. Here, we show that diacylglycerol kinase B (DGKB), a regulator of the intracellular concentration of diacylglycerol (DAG), is significantly downregulated in radioresistant GBM cells. The downregulation of DGKB increases DAG accumulation and decreases fatty acid oxidation, contributing to radioresistance by reducing mitochondrial lipotoxicity. Diacylglycerol acyltransferase 1 (DGAT1), which catalyzes the formation of triglycerides from DAG, is increased after ionizing radiation. Genetic inhibition of DGAT1 using short hairpin RNA (shRNA) or microRNA-3918 (miR-3918) mimic suppresses radioresistance. We discover that cladribine, a clinical drug, activates DGKB, inhibits DGAT1, and sensitizes GBM cells to radiotherapy in vitro and in vivo. Together, our study demonstrates that DGKB downregulation and DGAT1 upregulation confer radioresistance by reducing mitochondrial lipotoxicity and suggests DGKB and DGAT1 as therapeutic targets to overcome GBM radioresistance.


Asunto(s)
Diacilglicerol Quinasa , Glioblastoma , Humanos , Diacilglicerol Quinasa/genética , Diacilglicerol Quinasa/metabolismo , Diacilglicerol O-Acetiltransferasa/genética , Diacilglicerol O-Acetiltransferasa/metabolismo , Glioblastoma/genética , Glioblastoma/radioterapia , Lípidos/toxicidad , Triglicéridos/metabolismo , Regulación hacia Arriba
13.
Nutrients ; 15(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37513611

RESUMEN

Protaetia brevitarsis (PB)-derived bioactive substances have been used as food and medicine in many Asian countries because of their antioxidant, antidiabetic, anti-cancer, and hepatoprotective properties. However, the effect of PB extracts (PBE) on osteoclast differentiation is unclear. In this study, we investigated the effect of PBE on RANKL-induced osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs). To investigate the cytotoxicity of PBE, the viability of BMMs was confirmed via MTT assay. Tartrate-resistant acid phosphatase (TRAP) staining and pit assays were performed to confirm the inhibitory effect of PBE on osteoclast differentiation and bone resorption. The expression levels of osteoclast differentiation-related genes and proteins were evaluated using quantitative real-time PCR and Western blotting. PBE attenuated osteoclastogenesis in BMMs in TRAP and pit assays without cytotoxicity. The expression levels of osteoclast marker genes and proteins induced by RANKL were decreased after PBE treatment. PBE suppressed osteoclastogenesis by inhibiting the RANKL-induced activated JNK/NF-κB/PLCγ2 signaling pathway and the expression of NFATc1 and c-Fos. Collectively, these results suggest that PBE could be a potential therapeutic strategy or functional product for osteoclast-related bone disease.


Asunto(s)
Resorción Ósea , FN-kappa B , Animales , Ratones , FN-kappa B/metabolismo , Osteogénesis , Fosfolipasa C gamma/metabolismo , Osteoclastos , Sistema de Señalización de MAP Quinasas , Resorción Ósea/metabolismo , Ligando RANK/metabolismo , Diferenciación Celular
14.
Int J Biol Macromol ; 253(Pt 8): 127511, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37866557

RESUMEN

Glioblastoma Multiforme (GBM) is a malignant primary brain tumor. Radiotherapy, one of the standard treatments for GBM patients, could induce GBM radioresistance via rewiring cellular metabolism. However, the precise mechanism attributing to GBM radioresistance or targeting strategies to overcome GBM radioresistance are lacking. Here, we demonstrate that SLC25A22, a mitochondrial bi-directional glutamate transporter, is upregulated and showed uni-directionality from mitochondria to cytosol in radioresistant GBM cells, resulting in accumulating cytosolic glutamate. However, mitochondrial glutaminolysis-mediated TCA cycle metabolites and OCR are maintained constantly. The accumulated cytosolic glutamate enhances the glutathione (GSH) production and proline synthesis in radioresistant GBM cells. Increased GSH protects cells against ionizing radiation (IR)-induced reactive oxygen species (ROS) whereas increased proline, a rate-limiting substrate for collagen biosynthesis, induces extracellular matrix (ECM) remodeling, leading to GBM invasive phenotypes. Finally, we discover that genetic inhibition of SLC25A22 using miR-184 mimic decreases GBM radioresistance and aggressiveness both in vitro and in vivo. Collectively, our study suggests that SLC25A22 upregulation confers GBM radioresistance by rewiring glutamate metabolism, and SLC25A22 could be a significant therapeutic target to overcome GBM radioresistance.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/radioterapia , Glioblastoma/metabolismo , Ácido Glutámico , Tolerancia a Radiación/genética , Línea Celular Tumoral , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/metabolismo , Mitocondrias/metabolismo , Prolina , Proteínas de Transporte de Membrana Mitocondrial
15.
Environ Sci Technol ; 46(7): 4184-90, 2012 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-22380606

RESUMEN

Landfill gas (LFG), which is primarily composed of CH(4), CO(2), and N(2), is produced from the anaerobic digestion of organic materials. To investigate the feasibility of the storage and transportation of LFG via the formation of hydrate, we observed the phase equilibrium behavior of CO(2)-CH(4)-N(2) mixture hydrates. When the specific molar ratio of CO(2)/CH(4) was 40/55, the equilibrium dissociation pressures were gradually shifted to higher pressures and lower temperatures as the mole fraction of N(2) increased. X-ray diffraction revealed that the CO(2)-CH(4)-N(2) mixture hydrate prepared from the CO(2)/CH(4)/N(2) (40/55/5) gas mixture formed a structure I clathrate hydrate. A combination of Raman and solid-state (13)C NMR measurements provided detailed information regarding the cage occupancy of gas molecules trapped in the hydrate frameworks. The gas storage capacity of LFG hydrates was estimated from the experimental results for the hydrate formations under two-phase equilibrium conditions. We also confirmed that trace amounts of nonmethane organic compounds do not affect the cage occupancy of gas molecules or the thermodynamic stability of LFG hydrates.


Asunto(s)
Dióxido de Carbono/análisis , Metano/análisis , Nitrógeno/análisis , Eliminación de Residuos , Espectrometría Raman/métodos , Agua/química , Carbono/análisis , Cinética , Espectroscopía de Resonancia Magnética , Presión , Termodinámica , Difracción de Rayos X
16.
J Phys Chem A ; 116(10): 2435-8, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22364651

RESUMEN

The structural transformations and guest dynamics of methanol-loaded ß-form hydroquinone (HQ) clathrate were investigated using temperature-dependent Raman spectroscopy. Methanol-loaded ß-form HQ clathrate was obtained by recrystallization and characterized by elemental analysis, synchrotron X-ray diffraction, solid-state (13)C NMR spectroscopy, and Raman spectroscopy. Temperature-dependent Raman spectra of methanol-loaded ß-form HQ clathrate were measured in the temperature range 300-412 K at increments of 4 K. Although no significant changes were evident in the temperature range 300-376 K, abrupt changes in the relative intensity and shape of the Raman bands were observed between 380 and 412 K indicating the structural transition from methanol-loaded ß-form HQ clathrate to pure α-form HQ. Methanol molecules were gradually released from the ß-form HQ clathrate in the range 364-380 K. Upon returning to ambient conditions, the crystal structure of the HQ sample remained identical to that of pure α-form HQ. Therefore, the temperature-induced structural transition of methanol-loaded HQ clathrate is completely irreversible and α-form HQ is more stable at ambient conditions.


Asunto(s)
Hidroquinonas/química , Metanol/química , Temperatura , Termodinámica , Estructura Molecular , Espectrometría Raman
17.
ACS Appl Mater Interfaces ; 14(22): 25620-25628, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35537705

RESUMEN

The polyhedra unit structure (MOx) in an amorphous metal oxide network has more freedom and flexibility than the same unit structure in a crystalline phase. Consequently, a mild external stimulus (e.g., instant photonic and acoustic energy) could affect and change this network parameter, thereby enhancing and modulating the electrical properties. However, it is difficult to tune these atomic parameters solely while maintaining the metal oxide's initial global amorphous phase and thereby preventing mechanical instability at the film-substrate interface (i.e., cracking or distortion). Here, we report local disordering in an amorphous network of a solution-processable indium tin oxide (ITO) film, where the disordering is triggered by mild-light irradiation (<0.1 mJ/cm2). Through a combination of systematic characterizations of the global structural and chemical compositional changes in conjunction with extended X-ray absorption fine structure analyses, we revealed the distortion of the atomic structure in the amorphous network of the ITO film led to the formation of additional structural oxygen vacancies. Our findings enabled us to fabricate mechanical-instability-free, perfect amorphous-phase ITO thin films on plastic substrates, where the sheet resistance substantially decreased to ∼ 2 × 103 Ω/□. Furthermore, this sheet resistance did not vary when the film and substrate were bent to a radius of 2 mm and could operate at low temperatures. This work can pave the novel way to fabricate high-quality flexible transparent electrodes suitable for rapid, cost-effective, and patternable processing on plastic substrates, and the domain can be extended to flexible electronics.

18.
J Microbiol Biotechnol ; 32(2): 220-227, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-34866130

RESUMEN

The spread of antibiotic-resistant strains of Staphylococcus aureus, a gram-positive opportunistic pathogen, has increased due to the frequent use of antibiotics. Inhibition of the quorum-sensing systems of biofilm-producing strains using plant extracts represents an efficient approach for controlling infections. Torilis japonica is a medicinal herb showing various bioactivities; however, no studies have reported the anti-biofilm effects of T. japonica extracts against drug-resistant S. aureus. In this study, we evaluated the inhibitory effects of T. japonica ethanol extract (TJE) on biofilm production in methicillin-sensitive S. aureus (MSSA) KCTC 1927, methicillin-resistant S. aureus (MRSA) KCCM 40510, and MRSA KCCM 40511. Biofilm assays showed that TJE could inhibit biofilm formation in all strains. Furthermore, the hemolysis of sheep blood was found to be reduced when the strains were treated with TJE. The mRNA expression of agrA, sarA, icaA, hla, and RNAIII was evaluated using reverse transcription-polymerase chain reaction to determine the effect of TJE on the regulation of genes encoding quorum sensing-related virulence factors in MSSA and MRSA. The expression of hla reduced in a concentration-dependent manner upon treatment with TJE. Moreover, the expression levels of other genes were significantly reduced compared to those in the control group. In conclusion, TJE can suppress biofilm formation and virulence factor-related gene expression in MSSA and MRSA strains. The extract may therefore be used to develop treatments for infections caused by antibiotic-resistant S. aureus.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Antibacterianos/farmacología , Biopelículas , Etanol/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Ovinos , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus
19.
Biomedicines ; 10(6)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35740330

RESUMEN

Glioblastoma (GBM) is the most malignant primary brain tumor. The current standard approach in GBM is surgery, followed by treatment with radiation and temozolomide (TMZ); however, GBM is highly resistant to current therapies, and the standard of care has not been revised over the last two decades, indicating an unmet need for new therapies. GBM stem cells (GSCs) are a major cause of chemoresistance due to their ability to confer heterogeneity and tumorigenic capacity. To improve patient outcomes and survival, it is necessary to understand the properties and mechanisms underlying GSC chemoresistance. In this review, we describe the current knowledge on various resistance mechanisms of GBM to therapeutic agents, with a special focus on TMZ, and summarize the recent findings on the intrinsic and extrinsic mechanisms of chemoresistance in GSCs. We also discuss novel therapeutic strategies, including molecular targeting, autophagy inhibition, oncolytic viral therapy, drug repositioning, and targeting of GSC niches, to eliminate GSCs, from basic research findings to ongoing clinical trials. Although the development of effective therapies for GBM is still challenging, this review provides a better understanding of GSCs and offers future directions for successful GBM therapy.

20.
Int J Mol Med ; 49(4)2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35234274

RESUMEN

Myricetin, a flavonoid found in fruits and vegetables, is known to have antioxidant and anticancer effects. However, the anticancer effects of myricetin on SK­BR­3 human breast cancer cells have not been elucidated. In the present study, the anticancer effects of myricetin were confirmed in human breast cancer SK­BR­3 cells. As the concentration of myricetin increased, the cell viability decreased. DAPI (4',6­diamidino­2­phenylindole) and Annexin V/PI staining also revealed a significant increase in apoptotic bodies and apoptosis. Western blot analysis was performed to confirm the myricetin­induced expression of apoptosis­related proteins. The levels of cleaved PARP and Bax proteins were increased, and that of Bcl­2 was decreased. The levels of proteins in the mitogen­activated protein kinase (MAPK) pathway were examined to confirm the mechanism of myricetin­induced apoptosis, and it was found that the expression levels of phosphorylated c­Jun N­terminal kinase (p­JNK) and phosphorylated mitogen­activated protein kinases (p­p38) were increased, whereas that of phosphorylated extracellular­regulated kinase (p­ERK) was decreased. It was also demonstrated that myricetin induced autophagy by promoting autophagy­related proteins such as microtubule­associated protein 1A/1B­light chain 3 (LC 3) and beclin 1. In addition, 3­methyladenine (3­MA) was used to evaluate the association between cell viability and autophagy in cells treated with myricetin. The results showed that simultaneous treatment with 3­MA and myricetin promoted the apoptosis of breast cancer cells. Furthermore, treatment with a JNK inhibitor reduced cell viability, promoted Bax expression, and reduced the expression of p­JNK, Bcl­2, and LC 3­II/I. These results suggest that myricetin induces apoptosis via the MAPK pathway and regulates JNK­mediated autophagy in SK­BR­3 cells. In conclusion, myricetin shows potential as a natural anticancer agent in SK­BR­3 cells.


Asunto(s)
Apoptosis , Flavonoides , Sistema de Señalización de MAP Quinasas , Proteínas Quinasas Activadas por Mitógenos , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Flavonoides/farmacología , Humanos
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