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1.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-37955650

RESUMEN

Depression in bipolar disorder (BD-II) is frequently misdiagnosed as unipolar depression (UD) leading to inappropriate treatment and downstream complications for many bipolar sufferers. In this study, we evaluated whether neuromelanin-MR signal and volume changes in the substantia nigra (SN) can be used as potential biomarkers to differentiate BD-II from UD. The signal intensities and volumes of the SN regions were measured, and contrast-to-noise ratio (CNR) to the decussation of the superior cerebellar peduncles were calculated and compared between healthy controls (HC), BD-II and UD subjects. Results showed that compare to HC, both BD-II and UD subjects had significantly decreased CNR and increased volume on the right and left sides. Moreover, the volume in BD-II group was significantly increased compared to UD group. The area under the receiver operating characteristic curve (AUC) for discriminating BD from HC was the largest for the Volume-L (AUC, 0.85; 95% confidence interval [CI]: 0.77, 0.93). The AUC for discriminating UD from HC was the largest for the Volume-L (AUC, 0.76; 95% CI: 0.65, 0.86). Furthermore, the AUC for discriminating BD from UD was the largest for the Volume-R (AUC, 0.73; 95% CI: 0.62, 0.84). Our findings suggest that neuromelanin-sensitive magnetic resonance imaging techniques can be used to differentiate BD-II from UD.


Asunto(s)
Trastorno Bipolar , Trastorno Depresivo , Melaninas , Humanos , Trastorno Bipolar/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Sustancia Negra/diagnóstico por imagen
2.
Am J Physiol Lung Cell Mol Physiol ; 327(2): L150-L159, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38771147

RESUMEN

Alteration in the normal mechanical forces of breathing can contribute to changes in contractility and remodeling characteristic of airway diseases, but the mechanisms that mediate these effects in airway cells are still under investigation. Airway smooth muscle (ASM) cells contribute to both contractility and extracellular matrix (ECM) remodeling. In this study, we explored ASM mechanisms activated by mechanical stretch, focusing on mechanosensitive piezo channels and the key Ca2+ regulatory protein stromal interaction molecule 1 (STIM1). Expression of Ca2+ regulatory proteins, including STIM1, Orai1, and caveolin-1, mechanosensitive ion channels Piezo-1 and Piezo-2, and NLRP3 inflammasomes were upregulated by 10% static stretch superimposed on 5% cyclic stretch. These effects were blunted by STIM1 siRNA. Histamine-induced [Ca2+]i responses and inflammasome activation were similarly blunted by STIM1 knockdown. These data show that the effects of mechanical stretch in human ASM cells are mediated through STIM1, which activates multiple pathways, including Piezo channels and the inflammasome, leading to potential downstream changes in contractility and ECM remodeling.NEW & NOTEWORTHY Mechanical forces on the airway can contribute to altered contractility and remodeling in airway diseases, but the mechanisms are not clearly understood. Using human airway smooth muscle cells exposed to cyclic forces with static stretch to mimic breathing and static pressure, we found that the effects of stretch are mediated through STIM1, resulting in the activation of multiple pathways, including Piezo channels and the inflammasome, with potential downstream influences on contractility and remodeling.


Asunto(s)
Miocitos del Músculo Liso , Molécula de Interacción Estromal 1 , Humanos , Molécula de Interacción Estromal 1/metabolismo , Molécula de Interacción Estromal 1/genética , Miocitos del Músculo Liso/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/genética , Inflamasomas/metabolismo , Estrés Mecánico , Mecanotransducción Celular , Músculo Liso/metabolismo , Canales Iónicos/metabolismo , Caveolina 1/metabolismo , Caveolina 1/genética , Transducción de Señal , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Calcio/metabolismo , Células Cultivadas , Contracción Muscular/fisiología , Remodelación de las Vías Aéreas (Respiratorias)/fisiología , Proteína ORAI1/metabolismo , Proteína ORAI1/genética
3.
Mol Biol Rep ; 51(1): 139, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38236340

RESUMEN

BACKGROUND: Ferroptosis is involved in osteoarthritis development; however, the roles of long noncoding RNAs (lncRNAs), including lncRNA MEG3, in the regulation of ferroptosis in osteoarthritis are still unclear. METHODS: In this study, qRT‒PCR and Western blotting assays were used to detect the expression of lncRNA MEG3, miR-885-5p, SLC7A11 and GPX4; MDA and CCK-8 assays were applied to analyse cellular MDA levels and cell viability, respectively. RESULT: Erastin elevated cellular MDA levels and decreased the viability of chondrocytes and the erastin-induced decline in cell viability was reversed by a ferroptosis inhibitor (ferrostatin-1). Erastin downregulated lncRNA MEG3, SLC7A11 and GPX4 and upregulated miR-885-5p. Silencing of lncRNA MEG3 increased miR-885-5p and downregulated SLC7A11 and GPX4 and further sensitized chondrocytes to erastin-induced ferroptosis. In contrast, overexpression of lncRNA MEG3 had opposite effects. Dual luciferase assays confirmed binding between lncRNA MEG3 and miR-885-5p and between miR-885-5p and the 3'UTR of SLC7A11. In the synovial fluids from patients with osteoarthritis compared with synovial fluids from normal controls, the RNA levels of lncRNA MEG3 and SLC7A11 were decreased and the miR-885-5p expression level was increased. CONCLUSION: Our findings indicated that lncRNA MEG3 overexpression alleviated ferroptosis in chondrocytes by affecting the miR-885-5p/SLC7A11 signalling pathway.


Asunto(s)
Ferroptosis , MicroARNs , Osteoartritis , Piperazinas , ARN Largo no Codificante , Humanos , Sistema de Transporte de Aminoácidos y+/genética , Condrocitos , Ferroptosis/genética , MicroARNs/genética , Osteoartritis/genética , ARN Largo no Codificante/genética
4.
Nicotine Tob Res ; 26(4): 474-483, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-37535700

RESUMEN

INTRODUCTION: Electronic cigarettes (E-cigs) are in a controversial state. Although E-cig aerosol generally contains fewer harmful substances than smoke from burned traditional cigarettes, aerosol along with other compounds of the E-cigs may also affect lung functions and promote the development of lung-related diseases. We investigated the effects of E-cig on the pulmonary functions of male C57BL/6 mice and reveal the potential underlying mechanisms. METHODS: A total of 60 male C57BL/6 mice were randomly divided into four groups. They were exposed to fresh-air, traditional cigarette smoke, E-cig vapor with 12 mg/mL of nicotine, and E-cig with no nicotine for 8 weeks. Lung functions were evaluated by using quantitative analysis of the whole body plethysmograph, FlexiVent system, lung tissue histological and morphometric analysis, and RT-PCR analysis of mRNA expression of inflammation-related genes. In addition, the effects of nicotine and acrolein on the survival rate and DNA damage were investigated using cultured human alveolar basal epithelial cells. RESULTS: Exposure to E-cig vapor led to significant changes in lung functions and structures including the rupture of the alveolar cavity and enlarged alveolar space. The pathological changes were also accompanied by increased expression of interleukin-6 and tumor necrosis factor-α. CONCLUSIONS: The findings of the present study indicate that the safety of E-cig should be further evaluated. IMPLICATIONS: Some people currently believe that using nicotine-free E-cigs is a safe way to smoke. However, our research shows that E-cigs can cause lung damage regardless of whether they contain nicotine.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Ratones , Animales , Masculino , Humanos , Nicotina/efectos adversos , Nicotina/metabolismo , Ratones Endogámicos C57BL , Pulmón , Aerosoles/farmacología
5.
Heart Lung Circ ; 33(1): 111-119, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38161084

RESUMEN

OBJECTIVE: To evaluate the long-term outcomes of degenerative mitral valve (MV) repair. METHODS: This study analysed 1,069 patients who underwent MV repair due to degenerative MV disease at Beijing Anzhen Hospital from January 2010 to December 2019. All patients were clinically followed until December 2019, with an average follow-up period of 4.7 years. Perioperative complications, 30-day mortality, long-term outcomes, and risk factors of all-cause death and recurrent mitral regurgitation (MR) were summarised. RESULTS: Ten patients died in the hospital and 33 died during the follow-up period. Recurrent MR occurred in 113 patients. Fourteen patients underwent re-operation. Rates of long-term survival, absence of recurrent MR, and no re-operation were 94.0% (91.6%-96.6%), 81.2% (77.3%-85.3%), and 98.2% (97.2%-99.3%), respectively. The risk factors for long-term all-cause death included age and an ejection fraction (EF) <60%. The risk factors for recurrent MR included age, female sex, E-wave velocity, anterior prolapse, residual 1+MR postoperatively, and lower body mass index. CONCLUSIONS: Mitral valve repair is an effective treatment for degenerative MV disease that, in an experienced heart centre, can be performed with low mortality, recurrence, and re-operation rates. Advanced age and an EF <60% were risk factors for long-term all-cause death. Age, female sex, residual 1+MR postoperatively, lower body mass index, higher peak E-wave velocity, and anterior prolapse were risk factors for recurrent MR.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Insuficiencia de la Válvula Mitral , Humanos , Femenino , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/cirugía , Resultado del Tratamiento , Prolapso , Estudios Retrospectivos
6.
J Cell Sci ; 134(8)2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33758077

RESUMEN

Autophagy is considered to be an important switch for facilitating normal to malignant cell transformation during colorectal cancer development. Consistent with other reports, we found that the membrane receptor Neuropilin1 (NRP1) is greatly upregulated in colon cancer cells that underwent autophagy upon glucose deprivation. However, the mechanism underlying NRP1 regulation of autophagy is unknown. We found that knockdown of NRP1 inhibits autophagy and largely upregulates the expression of aldo-keto reductase family 1 B10 (AKR1B10). Moreover, we demonstrated that AKR1B10 interacts with and inhibits the nuclear importation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and then subsequently represses autophagy. Interestingly, we also found that an NADPH-dependent reduction reaction could be induced when AKR1B10 interacts with GAPDH, and the reductase activity of AKR1B10 is important for its repression of autophagy. Together, our findings unravel a novel mechanism of NRP1 in regulating autophagy through AKR1B10.


Asunto(s)
Aldehído Reductasa , Neoplasias del Colon , Aldehído Reductasa/genética , Aldo-Ceto Reductasas , Autofagia , Neoplasias del Colon/genética , Glucosa , Gliceraldehído-3-Fosfato Deshidrogenasas , Humanos
7.
Proc Biol Sci ; 290(2007): 20231333, 2023 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-37727088

RESUMEN

Many fossil insects show monochromatic colour patterns that may provide valuable insights into ancient insect behaviour and ecology. Whether these patterns reflect original pigmentary coloration is, however, unknown, and their formation mechanism has not been investigated. Here, we performed thermal maturation experiments on extant beetles with melanin-based colour patterns. Scanning electron microscopy reveals that melanin-rich cuticle is more resistant to degradation than melanin-poor cuticle: with progressive maturation, melanin-poor cuticle regions experience preferential thinning and loss, yet melanin-rich cuticle remains. Comparative analysis of fossil insects with monotonal colour patterns confirms that the variations in tone correspond to variations in preserved cuticle thickness. These preserved colour patterns can thus be plausibly explained as melanin-based patterning. Recognition of melanin-based colour patterns in fossil insects opens new avenues for interpreting the evolution of insect coloration and behaviour through deep time.


Asunto(s)
Escarabajos , Fósiles , Animales , Color , Melaninas , Insectos
8.
Virol J ; 20(1): 58, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005687

RESUMEN

BACKGROUND: Multiple host factors are involved in modulating type I interferon expression induced by viruses; however, the mechanism is not fully elucidated. Influenza A virus infection causes severe respiratory symptoms and triggers a series of signaling cascades and host innate immune responses, including interferon production. The co-IP/MS technology was used to screen several antiviral factors in the early stage. Among these factors, ariadne-1 homolog (ARIH1) caught our attention. METHODS: Western blot assay was performed to detect the level of proteins and software ImageJ was used to analyze the band intensities. Polymerase activity assay was conducted to evaluate the polymerase activity of influenza A virus. Tissue culture infective dose (TCID50) assay was performed to measure influenza A virus titers, and quantitative RT-PCR assay was applied to test the mRNA level of IFN-ß, ISG56, and CXCL10. Luciferase reporter assay was used to confirm the target of ARIH1 in RIG-I signaling. Immunoprecipitation assay was performed to detect the interaction and the ubiquitination of the proteins. All data were analyzed by biostatistical methods and presented as means ± standard deviation from three independent experiments. Statistical significance was determined using two-tailed student's t test. A P value of less than 0.05 was considered statistically significant, and a P value of less than 0.01 was considered highly significant (ns, P ≥ 0.05; *, P < 0.05; and **, P < 0.01). RESULTS: We found that ARIH1, a member of E3 ubiquitin ligases, enhanced cellular antiviral responses. Subsequent study showed that ARIH1 was up-regulated during influenza A virus infection. Further analysis showed that ARIH1 enhanced IFN-ß and downstream gene expression by affecting the degradation of RIG-I through the SQSTM1/p62 signaling pathway. CONCLUSION: This newly revealed mechanism shows that cellular response increases of ARIH1 and promotes IFN-ß expression to boost host survival during viral infection.


Asunto(s)
Virus de la Influenza A , Gripe Humana , Humanos , Proteína Sequestosoma-1/metabolismo , Proteína 58 DEAD Box/metabolismo , Inmunidad Innata , Transducción de Señal , Antivirales , Replicación Viral , Ubiquitina-Proteína Ligasas
9.
Inorg Chem ; 62(42): 17115-17125, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37828769

RESUMEN

Cu-O2 structures play important roles in bioinorganic chemistry and enzyme catalysis, where the bonding between the Cu and O2 parts serves as a fundamental research concern. Here, we performed a multiconfigurational study on the copper L2,3-edge X-ray absorption spectra (XAS) of two copper enzyme model complexes to gain a better understanding of the antibonding nature from the clearly interpreted structure-spectroscopy relation. We obtained spectra in good agreement with the experiments by using the restricted active space second-order perturbation theory (RASPT2) method, which facilitated reliable chemical analysis. Spectral feature interpretations were supported by computing the spin-orbit natural transition orbitals. All major features were assigned to be mainly from Cu 2p to antibonding orbitals between Cu 3d and O2 π*, Cu 3d-πO-O* (type A), and a few also to mixed antibonding/bonding orbitals between Cu 3d and O2 π, Cu 3d ± πO-O (type M). Our calculations provided a clear illustration of the interactions between Cu 3d and O2 π*/π orbitals that are carried in the metal L-edge XAS.

10.
Postgrad Med J ; 99(1174): 875-882, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-36977337

RESUMEN

PURPOSE: This study aims to develop an accurate and simplified scoring system based on the national early warning score (NEWS) to predict the mortality of intensive care unit (ICU) patients. METHODS: The information of patients was retrieved from the Medical Information Mart for Intensive Care (MIMIC)-III and -IV databases. The Modified National Early Warning Score (MNEWS) of the patients was calculated. The discrimination ability of the MNEWS, acute physiology and chronic health scoring system II (APACHE II), and original NEWS systems in predicting patients' mortality was evaluated using area under the receiver operating characteristic (AUROC) analysis. The DeLong test was used to estimate the receiver operating characteristic curve. The Hosmer-Lemeshow goodness-of-fit test was then applied to evaluate the calibration of the MNEWS. RESULTS: In total, 7275 ICU patients from the MIMIC-III and -IV databases were included in the derivation cohort and 1507 ICU patients from Xi'an Medical University were included in the validation cohort. In the derivation cohort, the nonsurvivors had significantly higher MNEWSs than the survivors (12.5 ± 3.4 vs 8.8 ± 3.4, P < 0.05). MNEWS and APACHE II both had a better performance than the NEWS in predicting hospital mortality and 90-day mortality. The optimal cutoff of MNEWS was 11. Patients with an MNEWS ≥ 11 had significantly shorter survival than those having an MNEWS of <11. Furthermore, MNEWS had a high calibration ability in predicting hospital mortality of ICU patients (χ2 = 6.534 and P = 0.588) by the Hosmer-Lemeshow test. This finding was confirmed in the validation cohort. CONCLUSION: MNEWS is a simple and accurate scoring system for evaluating the severity and predicting the outcomes of ICU patients.


Asunto(s)
Puntuación de Alerta Temprana , Unidades de Cuidados Intensivos , Humanos , Cuidados Críticos , APACHE , Mortalidad Hospitalaria , Curva ROC , Pronóstico
11.
Mol Pharm ; 19(7): 2607-2619, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35485954

RESUMEN

Chlorin e6-C-15-ethyl ester (LS-HB), a newly identified photosensitizer, was isolated from chlorin e6. The mechanism of tumor cell death induced by photodynamic therapy with LS-HB (LS-HB-PDT) is still unknown. Here, we investigated the photophysical properties of LS-HB, evaluated the antitumor effect on melanoma in vitro and in vivo, and explored its possible mechanisms. LS-HB not only has an optimal spectral band of red wavelength (660 nm) for photosensitization but also has favorable photostability. More importantly, LS-HB-PDT elicited a potent dose-dependent phototoxic effect in vitro. We discovered that LS-HB located in the mitochondria of B16F10 cells was able to generate excess reactive oxygen species, which subsequently resulted in mitochondrial membrane potential loss and induced apoptosis via caspase-9 and caspase-3 pathways. Moreover, PDT with LS-HB markedly inhibited the growth of melanoma in vivo. Therefore, LS-HB is expected to be an effective potential photosensitizer in antitumor therapy.


Asunto(s)
Melanoma , Fotoquimioterapia , Porfirinas , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Humanos , Melanoma/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/farmacología , Porfirinas/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo
12.
Mol Pharm ; 19(5): 1356-1367, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35420039

RESUMEN

Selectively inducing tumor thrombosis and subsequent necrosis is a novel and promising antitumor strategy. We have previously designed a targeting procoagulant protein, called tTF-EG3287, which is a fusion of a truncated tissue factor (tTF) with EG3287, a short peptide against the neuropilin-1 (NRP1) binding site of vascular endothelial growth factor-A 165 (VEGF-A 165). However, off-target effects and high-dose requirements limit the further use of tTF-EG3287 in antitumor therapy. Therefore, we encapsulated tTF-EG3287 into poly(2-ethyl-2-oxazoline)-distearoyl phosphatidyl ethanolamine (PEOz-DSPE)-modified liposomes to construct pH-responsive liposomes as a novel vascular embolization agent, called tTF-EG3287@Liposomes. The liposomes had an average particle size of about 100 nm and showed considerable drug-loading capacity, encapsulation efficiency, and biocompatibility. Under the stimulation of acidic microenvironments (pH 6.5), the lipid membrane of tTF-EG3287@Liposomes collapsed, and the cumulative drug release rate within 72 h was 83 ± 1.26%. When administered to a mouse model of hepatocellular carcinoma (HCC), tTF-EG3287@Liposomes showed prolonged retention and enhanced accumulation in the tumor as well as a superior antitumor effec, compared with tTF-EG3287. This study demonstrates the potential of tTF-EG3287@Liposomes as a novel embolic agent for solid tumors and provides a new strategy for tumor-targeted infarction therapy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Concentración de Iones de Hidrógeno , Liposomas/química , Neoplasias Hepáticas/tratamiento farmacológico , Ratones , Tromboplastina , Microambiente Tumoral , Factor A de Crecimiento Endotelial Vascular
13.
Arch Virol ; 167(10): 1989-1997, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35790643

RESUMEN

Hand, foot, and mouth disease (HFMD) is a serious threat to the health of infants, and it can be caused by enterovirus 71 (EV71). The clinical symptoms are mostly self-limiting, but some infections develop into aseptic meningitis with poor prognosis and even death. In this study, urolithin A (UroA), an intestinal metabolite of ellagic acid, significantly inhibited the replication of EV71 in cells. Further evaluation showed that UroA was better than ribavirin in terms of its 50% cytopathic concentration (CC50), 50% inhibitory concentration (IC50), and selectivity index. Moreover, UroA inhibited the proliferation of EV71 by promoting autophagy and apoptosis of infected cells. Therefore, UroA is a candidate drug for the treatment of EV71 infection.


Asunto(s)
Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , Apoptosis , Autofagia , Cumarinas , Humanos , Lactante
14.
Phys Chem Chem Phys ; 24(14): 8196-8207, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35311874

RESUMEN

Polynitrogen molecules and ions are important building blocks of high energy density compounds (HEDCs). High energy bonds formed at the N sites can be effectively probed by X-ray photoelectron spectroscopy (XPS) at the N K-edge. In this work, with the density functional theory and the ΔKohn-Sham scheme, we simulated the N1s ionic potentials (IPs) of 72 common polynitrogen molecules [tetrazoles, pentazole (N5H), diazines, triazines, tetrazines, furazans, oxazoles and oxadiazoles], ions [pentazolate anion (cyclo-N5-), pentazenium cation (N5+), etc.], and molecular (NH3⋯N5H, H2O⋯N5H) and ionic (NH4+⋯N5-, H3O+⋯N5-) pairs, as well as mononitrogen relatives. These constitute a small theoretical database for absolute N1s IPs with an average accuracy of ca. 0.3 eV. To understand the structure-IP relationship within this family, effects of side substituent and bridging groups, local bonding types (amine or imine N), charge and protonation states, and vibronic coupling were analyzed based on selected systems. This study in the gas phase collects inherent chemical shifts of nitrogen in high-energy NN and NC bonds, which provides an essential reference into XPS interpretations of more complex HEDCs in the solid state. We especially highlight the evident N1s chemical shifts induced by protonation for nitrogen in the five-membered ring (N5H versus cyclo-N5-, ca. 7 eV; NH3⋯N5H versus NH4+⋯N5-, ca. 3 eV; H2O⋯N5H versus H3O+⋯N5-, ca. 2 eV), and suggest XPS as a sensitive tool in determining the hydrogen positions in pentanitrogen-based HEDCs.

15.
J Chem Phys ; 157(9): 094704, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36075707

RESUMEN

Truncated cluster models represent an effective way for simulating x-ray spectra of 2D materials. Here, we systematically assessed the influence of two key parameters, the cluster shape (honeycomb, rectangle, or parallelogram) and size, in x-ray photoelectron (XPS) and absorption (XAS) spectra simulations of three 2D materials at five K-edges (graphene, C 1s; C3N, C/N 1s; h-BN, B/N 1s) to pursue the accuracy limit of binding energy (BE) and spectral profile predictions. Several recent XPS experiments reported BEs with differences spanning 0.3, 1.5, 0.7, 0.3, and 0.3 eV, respectively. Our calculations favor the honeycomb model for stable accuracy and fast size convergence, and a honeycomb with ∼10 nm side length (120 atoms) is enough to predict accurate 1s BEs for all 2D sheets. Compared to all these experiments, predicted BEs show absolute deviations as follows: 0.4-0.7, 0.0-1.0, 0.4-1.1, 0.6-0.9, and 0.1-0.4 eV. A mean absolute deviation of 0.3 eV was achieved if we compare only to the closest experiment. We found that the sensitivity of computed BEs to different model shapes depends on systems: graphene, sensitive; C3N, weak; and h-BN, very weak. This can be attributed to their more or less delocalized π electrons in this series. For this reason, a larger cluster size is required for graphene than the other two to reproduce fine structures in XAS. The general profile of XAS shows weak dependence on model shape. Our calculations provide optimal parameters and accuracy estimations that are useful for x-ray spectral simulations of general graphene-like 2D materials.

17.
Ecotoxicol Environ Saf ; 223: 112590, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34364127

RESUMEN

Arsenic exposure is related to insulin resistance (IR). However, the underlying mechanism is still uncertain. NOD-like receptors containing pyrin domain 3 (NLRP3) inflammasome is a key driving factor of IR. We found that NaAsO2 caused hepatic IR, activated NLRP3 inflammasome, and inhibited glycolysis pathway in vivo. We also found that tricarboxylic acid cycle (TCA cycle) was inhibited, and the content of hepatic lactate was upregulated with the treatment of arsenic. Consistent with these findings, we found that NLRP3 inflammasome and glycolysis were involved in the development of IR in L-02 cells. Besides, inhibiting NLRP3 inflammasome upregulated aerobic glycolysis and inhibited anaerobic glycolysis. Moreover, we demonstrated that NLRP3 inflammasome could bind to pyruvate kinase, liver and RBC (PKLR). Simultaneously, insulin signaling rather than NLRP3 inflammasome activation was altered by overexpressing PKLR. In summary, after treatment with NaAsO2, NLRP3 inflammasome blocked the glycolytic pathway via binding to PKLR, which in turn caused hepatic IR. This study shed new light on the molecular mechanism underlying arsenic-induced IR.


Asunto(s)
Arsénico , Resistencia a la Insulina , Animales , Arsénico/toxicidad , Inflamasomas , Hígado , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Piruvato Quinasa
19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 159-164, 2020 Mar.
Artículo en Zh | MEDLINE | ID: mdl-32220182

RESUMEN

OBJECTIVE: To investigate the effects of enterovirus 71 (EV71) on mitochondrial dynamics in human Glioma U251 cells. METHODS: The EV71 was replicated in Vero cells and the 50% tissue culture infective dose (TCID 50) was calculated based on the Reed-Muench formula. After the U251 cells were infected with EV71, the cellular morphology was assessed through the light microscope. The mitochondrial morphology was detected by MitoTracker Deep Red staining under laser confocal microscopy and the mitochondrial ultrastructure was visualized by transmission electron microscopy. The expressions of mitochondrial fission proteins Drp1, p-Drp1 and fusion protein Opa1 were examined by Western blot. The level of ATP was measured by a commercial ATP assay kit. The generation of mitochondrial superoxide was detected by MitoSOX staining. RESULTS: The TCID 50 of EV71 was 10 -5.4/0.1 mL. Twenty-four or 48 h after EV71 infection, the U251 cells appeared shrunken, round and dead. The laser confocal microscopy and transmission electron microscopy images showed that the EV71 infection induced mitochondrial elongation and cristae damage. Moreover, Western blot analysis demonstrated that the protein expressions of Drp1 and Opa1 were downregulated at both 24 and 48 h after EV71 infection in U251 cells, companied with a significant increase in Drp1 phosphorylation at 48 h after infection ( P<0.05). In addition, a decreased ATP level and elevated mitochondrial superoxide generation were observed in the EV71 infected group, as compared to the control group. CONCLUSION: Our study demonstrated that infection with EV71 led to changes of mitochondrial morphology and dynamics in U251 cells, which may impair mitochondrial function and contribute to nervous system dysfunction.


Asunto(s)
Neoplasias Encefálicas/virología , Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Glioma/virología , Dinámicas Mitocondriales , Animales , Chlorocebus aethiops , Enterovirus Humano A/patogenicidad , Infecciones por Enterovirus/complicaciones , Humanos , Sistema Nervioso/fisiopatología , Sistema Nervioso/virología , Células Tumorales Cultivadas , Células Vero
20.
J Cell Physiol ; 234(8): 12828-12838, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30549035

RESUMEN

The incidence and mortality of lung cancer ranked the first among all types of cancer in China, and non-small cell lung cancer (NSCLC) is the most common type of lung cancer accounting for 85% of all lung cancers. Given that the survival rate of patients with advanced NSCLC is still poor nowadays, identification of novel therapeutic targets and the development of effective therapies are desired for the treatment of NSCLC in clinics. In this study, we reported the upregulation of ornithine aminotransferase (OAT) in NSCLC cells and clinical tumor samples as well as its association with the advanced TNM stage, metastasis, and poor tumor differentiation of lung cancer. Using different NSCLC cell lines, we demonstrated that OAT promoted the proliferation, invasion, and migration, inhibited the apoptosis, and altered cell cycle of NSCLC cells; besides, the involvement of OAT-miR-21-glycogen synthase kinase-3ß signaling in the functional role of OAT in NSCLC was also revealed. Importantly, in the absence of OAT, the growth and metastasis of tumor lung cancer xenograft was significantly suppressed in the nude mice. Based on our findings, OAT may be a potential novel biomarker for the diagnosis and therapeutic outcome monitoring of NSCLC. Inhibition of OAT may also represent a new therapeutic strategy of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , MicroARNs/efectos de los fármacos , Ornitina-Oxo-Ácido Transaminasa/farmacología , Adulto , Anciano , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Movimiento Celular/fisiología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/genética , Persona de Mediana Edad , Regulación hacia Arriba
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