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1.
J Med Virol ; 96(4): e29592, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38587184

RESUMEN

The role of human papillomavirus 16 (HPV 16) in esophageal squamous cell carcinoma (ESCC) remains uncertain. Therefore, this study aimed to investigate the prevalence of HPV 16 in patients with ESCC and its impact on theirprognosis. HPV 16 was detected using FISH, and TP53 status was evaluated via immunohistochemistry. The factors influencing prognosis were ananalyzed using the Log-rank test and Cox regression analyses. Among 178 patients with ESCC, 105 and 73 patients were categorized into concurrent chemoradiotherapy (CCRT) and postoperative chemoradiotherapy (POCRT) cohorts, respectively. Among 178 patients, 87 (48.87%) tested positive for HPV 16. Log-rank tests revealed that the overall survival (OS) of patients with ESCC who were HPV 16-positive was longer than that of those who were HPV 16-negative (median OS: 57 months vs. 27 months, p < 0.01**). HPV 16 infection and TP53 mutation status were identified as independent events. The OS of patients with mutant TP53 who were HPV 16-positive was longer than that of those who were HPV 16-negative in both CCRT and POCRT cohorts (p = 0.002** for CCRT cohorts and p = 0.0023** for POCRT cohorts). Conversely, HPV 16 infection had no effect on OS in the wild-type TP53 subgroup (p = 0.13 and 0.052 for CCRT and POCRT cohorts, respectively). As a conclusion, the positive rate of HPV 16 in ESCC in this study was 48.87% (87/178). Among the patients with ESCC who had TP53 mutation, those who were HPV 16-positive exhibited a better prognosis than those who were HPV 16-negative.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Infecciones por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Esófago/radioterapia , Papillomavirus Humano 16/genética , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/patología , Estudios Retrospectivos , Quimioradioterapia , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología
2.
Shanghai Kou Qiang Yi Xue ; 33(1): 49-53, 2024 Feb.
Artículo en Chino | MEDLINE | ID: mdl-38583024

RESUMEN

PURPOSE: To study the antimicrobial effect of different concentrations of new bioactive glass(BG) on common bacteria in apical periodontitis of deciduous teeth. METHODS: The diameter (mm) of the inhibitory rings formed after treatment of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum with the new bioactive glass was detected and observed by paper diffusion method, and the minimal inhibitory concentration(MIC), minimal bactericidal concentration (MBC) and minimal biofilm eradication concentration (MBEC) of E. faecalis, P. gingivalis and C. pseudomallei were determined. The mixed plaques of the three bacteria were treated with 20, 40, 60 and 80 mg/mL of the new bioactive glass for 24 h. The results were analyzed by laser confocal microscopy. The antibacterial effect of the new bioactive glass on the mixed plaque was observed by confocal laser scanning microscopy (CLSM). Statistical analysis was performed with GraphPad Prism 10.0 software. RESULTS: The new bioactive glass showed strong antibacterial potential against the common bacteria of apical periodontitis; the MBEC of the new bioactive glass on the plaque was significantly greater than MIC and MBC of Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum, and as the concentration of the new bioactive glass increased, the number of dead bacteria in the mixed plaque increased, and there was significant difference from that of the blank control group (P<0.05). CONCLUSIONS: The novel bioactive glass shows significant antibacterial efficacy against Enterococcus faecalis, Porphyromonas gingivalis and Clostridium nucleatum, which are the common bacteria in apical periodontitis of deciduous teeth.


Asunto(s)
Antibacterianos , Periodontitis Periapical , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Porphyromonas gingivalis , Diente Primario , Biopelículas
3.
Small Methods ; : e2301594, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263805

RESUMEN

The mass-transfer of oxygen in liquid phases (including in the bulk electrolyte and near the electrode surface) is a critical step to deliver oxygen to catalyst sites (especially immersed catalyst sites) and use the full capacity of oxygen reduction reaction (ORR). Despite the extensive efforts of optimizing the complex three-phase reaction interfaces to enhance the gaseous oxygen transfer, strong limitations remain due to oxygen's poor solubility and slow diffusion in electrolytes. Herein, a magnetic method for boosting the directional hydrodynamic pumping of oxygen toward immersed catalyst sites is demonstrated which allows the ORR to reach otherwise inaccessible catalytic regions where high currents normally would have depleted oxygen. For Pt foil electrodes without forced oxygen saturation in KOH electrolytes, the mass-transfer-limited current densities can be improved by 60% under an external magnetic field of 435 mT due to the synergistic effect between bulk- and surface-magnetohydrodynamic (MHD) flows induced by Lorentz forces. The residual magnetic fields are further used at the surface of magnetic materials (such as CoPt alloys and Pt/FeCo heterostructures) to enhance the surface-MHD effect, which helps to retain part of the ORR enhancement permanently without applying external magnetic fields.

4.
Alcohol ; 115: 5-12, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37481044

RESUMEN

Astrocytes are an important regulator of alcohol dependence. Furthermore, the downregulation of Rho-associated coiled coil-containing protein kinase 2 (ROCK2) attenuates alcohol-induced inflammation and oxidative stress in astrocytes. On the basis of these findings, we examined the effects of alcohol and a Rho/RACK kinases inhibitor on astrocyte function and investigated their effects on mRNA expression to further explore the protective mechanisms of a Rho/RACK kinases inhibitor in astrocytes after alcohol exposure. CTX TNA2 astrocytes were cultured with alcohol and Rho/RACK kinases inhibitor intervention before undergoing transcriptome sequencing, quantitative reverse transcription polymerase chain reaction (qRT-PCR), and wound healing assays. Alcohol exposure modulated cell morphology and inhibited astrocyte migration, whereas Fasudil improved cell morphology and promoted astrocyte migration after alcohol exposure. Transcriptome sequencing results indicated that alcohol exposure modulates the expression of genes involved in astrocyte development. Fasudil reversed the effects of alcohol exposure on the astrocyte developmental process. Four genes related to the developmental process and migration - Ccl2, Postn, Itga8, and Serpine1 - with the highest protein-protein interaction correlations (node degree >7) were selected for verification by qRT-PCR, and the results were consistent with those of the sequencing and wound healing assays. Our results suggest that the Rho/ROCK pathway is essential for alcohol to be able to interfere with astrocyte development and migration gene expression. The Rho/ROCK pathway inhibitor Fasudil reversed the adverse effects of alcohol exposure on astrocytes and may have clinical applications.


Asunto(s)
1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Astrocitos , Inhibidores de Proteínas Quinasas , Astrocitos/metabolismo , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Etanol/farmacología
5.
Adv Mater ; 35(8): e2207353, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36479745

RESUMEN

Ferromagnetic metals show great prospects in ultralow-power-consumption spintronic devices, due to their high Curie temperature and robust magnetization. However, there is still a lack of reliable solutions for giant and reversible voltage control of magnetism in ferromagnetic metal films. Here, a novel space-charge approach is proposed which allows for achieving a modulation of 30.3 emu/g under 1.3 V in Co/TiO2 multilayer granular films. The robust endurance with more than 5000 cycles is demonstrated. Similar phenomena exist in Ni/TiO2 and Fe/TiO2 multilayer granular films, which shows its universality. The magnetic change of 107% in Ni/TiO2 underlines its potential in a voltage-driven ON-OFF magnetism. Such giant and reversible voltage control of magnetism can be ascribed to space-charge effect at the ferromagnetic metals/TiO2 interfaces, in which spin-polarized electrons are injected into the ferromagnetic metal layer with the adsorption of lithium-ions on the TiO2 surface. These results open the door for a promising method to modulate the magnetization in ferromagnetic metals, paving the way toward the development of ionic-magnetic-electric coupled applications.

6.
Sci Bull (Beijing) ; 67(11): 1145-1153, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36545981

RESUMEN

Interfacial space charge storage between ionic and electronic conductor is a promising scheme to further improve energy and power density of alkali metal ion batteries (AMIBs). However, the general behavior of space charge storage in AMIBs has been less investigated experimentally, mostly due to the complicated electrochemical behavior and lack of proper characterization techniques. Here, we use operando magnetometry to verify that in FeSe2 AMIBs, abundant Li+/Na+/K+ (M+) can be stored at M2Se phase while electrons accumulate at Fe nanoparticles, forming interfacial space charge layers. Magnetic and dynamics tests further demonstrate that with increasing ionic radius from Li+, Na+ to K+, the reaction kinetics can be hindered, resulting in limited Fe formation and reduced space charge storage capacity. This work lays solid foundation for studying the complex interfacial effect in electrochemical processes and designing advanced energy storage devices with substantial capacity and considerable power density.

7.
J Am Chem Soc ; 143(32): 12800-12808, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34369752

RESUMEN

In spite of the excellent electrochemical performance in lithium-ion batteries (LIBs), transition-metal compounds usually show inferior capacity and cyclability in sodium-ion batteries (SIBs), implying different reaction schemes between these two types of systems. Herein, coupling operando magnetometry with electrochemical measurement, we peformed a comprehensive investigation on the intrinsic relationship between the ion-embedding mechanisms and the electrochemical properties of the typical FeS2/Na (Li) cells. Operando magnetometry together with ex-situ transmission electron microscopy (TEM) measurement reveal that only part of FeS2 is involved in the conversion reaction process, while the unreactive parts form "inactive cores" that lead to the low capacity. Through quantification with Langevin fitting, we further show that the size of the iron grains produced by the conversion reaction are much smaller in SIBs than that in LIBs, which may lead to more serious pulverization, thereby resulting in worse cycle performance. The underlying reason for the above two above phenomena in SIBs is the sluggish kinetics caused by the larger Na-ion radius. Our work paves a new way for the investigation of novel SIB materials with high capacity and long durability.

8.
Front Med (Lausanne) ; 8: 639453, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33968953

RESUMEN

Background: The prevalence and prognostic value of heart failure (HF) stages among elderly hospitalized patients is unclear. Methods: We conducted a prospective, observational, multi-center, cohort study, including hospitalized patients with the sample size of 1,068; patients were age 65 years or more, able to cooperate with the assessment and to complete the echocardiogram. Two cardiologists classified all participants in various HF stages according to 2013 ACC/AHA HF staging guidelines. The outcome was rate of 1-year major adverse cardiovascular events (MACE). The Kaplan-Meier method and Cox proportional hazards models were used for survival analyses. Survival classification and regression tree analysis were used to determine the optimal cutoff of N-terminal pro-brain natriuretic peptide (NT-proBNP) to predict MACE. Results: Participants' mean age was 75.3 ± 6.88 years. Of them, 4.7% were healthy and without HF risk factors, 21.0% were stage A, 58.7% were stage B, and 15.6% were stage C/D. HF stages were associated with worsening 1-year survival without MACE (log-rank χ2 = 69.62, P < 0.001). Deterioration from stage B to C/D was related to significant increases in HR (3.636, 95% CI, 2.174-6.098, P < 0.001). Patients with NT-proBNP levels over 280.45 pg/mL in stage B (HR 2; 95% CI 1.112-3.597; P = 0.021) and 11,111.5 pg/ml in stage C/D (HR 2.603, 95% CI 1.014-6.682; P = 0.047) experienced a high incidence of MACE adjusted for age, sex, and glomerular filtration rate. Conclusions : HF stage B, rather than stage A, was most common in elderly inpatients. NT-proBNP may help predict MACE in stage B. Trial Registration: ChiCTR1800017204; 07/18/2018.

9.
J Sci Food Agric ; 101(13): 5627-5635, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33713049

RESUMEN

BACKGROUND: Nanoparticles can improve the bioavailability of bioactive compounds. Concomitant intake of food can affect pharmacokinetic profiles by altering dissolution, absorption, metabolism, and elimination behavior. Studies on the effects of food and its supplements on the bioavailability of bioactives in nanoformulations are few. In this study, the effects of typical food (milk, sugar, high-fat diet, and regular kibble) and a widely consumed probiotic [Bifidobacterium lactis Bb-12® (Bb-12)] on the bioavailability of curcumin in four formulations [simply suspended curcumin (Cur-SS) and curcumin in nanoemulsions (Cur-NEs), in single-walled carbon nanotubes (Cur-SWNTs), and in nanostructured lipid carriers (Cur-NLCs)] were investigated. RESULTS: Fasting treatment and sugar co-ingestion can significantly enhance the bioavailability of curcumin in Cur-NEs and Cur-SWNTs, respectively. Compared with the fasting treatment, co-ingestion with regular kibble reduced the absorption of curcumin in Cur-NEs and Cur-SWNTs. Ingesting milk along with Cur-NE is also not recommended. The mechanisms behind these phenomena were briefly discussed. This study revealed for the first time that the intestinal colonization of Bb-12 reduces the bioavailability of curcumin and this reduction can be attenuated by nanoformulations SWNTs and NLCs, but not NEs. The reason for this difference was the protective effects of the former two nanoformulations against curcumin degradation by Bb-12 according to in vitro experiments. CONCLUSION: Dietary status (including supplementary probiotics) can dramatically influence the bioavailability of curcumin in nanoformulations. © 2021 Society of Chemical Industry.


Asunto(s)
Curcumina/química , Composición de Medicamentos/métodos , Grasas/metabolismo , Leche/metabolismo , Probióticos/química , Animales , Bifidobacterium animalis/química , Disponibilidad Biológica , Bovinos , Curcumina/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Grasas/química , Ratones , Ratones Endogámicos BALB C , Leche/química , Nanopartículas/química , Nanotubos de Carbono/química , Tamaño de la Partícula , Probióticos/metabolismo , Solubilidad
10.
Adv Mater ; 33(12): e2006629, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33576103

RESUMEN

Cobalt oxide (CoO) is a promising electrode for high-energy-density Li-ion batteries (LIBs), where the charge storage is believed to take place solely during the electrochemical oxidation/reduction processes. However, this simple picture has been increasingly challenged by reported anomalously large storage capacities, indicating the existence of undiscovered extra charge reservoirs inside the system. Here, an advanced operando magnetometry technology is employed to monitor the magnetization variation of the CoO LIBs in real time and, in this particular system, it is clearly demonstrated that the anomalous capacity is associated with both the reversible formation of a spin capacitor and the growth of a polymeric film at low voltages. Furthermore, operando magnetometry provides direct evidence of the catalytic role of metallic Co in assisting the polymeric film formation. These critical findings help pave the way for better understanding of the charge storage mechanisms of transition-metal oxides and further utilizing them to design novel electrode materials.

11.
Exp Gerontol ; 146: 111235, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33453322

RESUMEN

OBJECTIVE: Chronic inflammation is associated with major adverse cardiovascular events (MACEs), mortality, and frailty. Our aim was to add high-sensitivity C-reactive protein (hsCRP) to the frailty assessment to predict its association with prognosis of older adults with cardiovascular disease (CVD). METHODS: A comprehensive geriatric assessment was conducted at baseline in 720 in-patients aged ≥65 years with CVD. We divided the population into frailty and non-frailty groups according to the Fried phenotype, and hsCRP was further combined with frailty to stratify all patients into c-frailty and non-c-frailty groups. Predictive validity was tested using Cox proportional hazards regression model analysis and the discriminative ability was evaluated by receiver operating characteristic (ROC) curves. RESULTS: Of all the subjects enrolled, 51.0% were male and the mean age was 75.32 ± 6.52 years. The all-cause death and MACE rate was 6.4% at the 1-year follow-up. Frailty and c-frailty were independent predictors of all-cause death and MACE (hazard ratio [HR]: 2.55, 95% confidence interval [CI]: 1.35-4.83, p = 0.004; HR: 3.67, 95% CI: 1.83-7.39, p < 0.001). Adding hsCRP to the frailty model resulted in a significant increase in the area under the ROC curve from 0.74 (95% CI: 0.70-0.77) to 0.77 (95% CI: 0.71-0.84) (p = 0.0132) and a net reclassification index of 7.9% (95% CI: 1.96%-12.56%, p = 0.012). CONCLUSION: Adding hsCRP to the frailty assessment is helpful to identify a subgroup of older CVD patients with a higher risk of death and MACE over a period of 1 year. TRIAL REGISTRATION: ChiCTR1800017204; date of registration: 07/18/2018. URL: http://www.chictr.org.cn/showproj.aspx?proj=28931.


Asunto(s)
Enfermedades Cardiovasculares , Fragilidad , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/análisis , Femenino , Anciano Frágil , Fragilidad/diagnóstico , Evaluación Geriátrica , Humanos , Pacientes Internos , Masculino , Factores de Riesgo
12.
Nat Mater ; 20(1): 76-83, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32807921

RESUMEN

In lithium-ion batteries (LIBs), many promising electrodes that are based on transition metal oxides exhibit anomalously high storage capacities beyond their theoretical values. Although this phenomenon has been widely reported, the underlying physicochemical mechanism in such materials remains elusive and is still a matter of debate. In this work, we use in situ magnetometry to demonstrate the existence of strong surface capacitance on metal nanoparticles, and to show that a large number of spin-polarized electrons can be stored in the already-reduced metallic nanoparticles (that are formed during discharge at low potentials in transition metal oxide LIBs), which is consistent with a space charge mechanism. Through quantification of the surface capacitance by the variation in magnetism, we further show that this charge capacity of the surface is the dominant source of the extra capacity in the Fe3O4/Li model system, and that it also exists in CoO, NiO, FeF2 and Fe2N systems. The space charge mechanism revealed by in situ magnetometry can therefore be generalized to a broad range of transition metal compounds for which a large electron density of states is accessible, and provides pivotal guidance for creating advanced energy storage systems.

13.
ACS Nano ; 14(9): 11319-11326, 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32812734

RESUMEN

Linear magnetoresistance is generally observed in polycrystalline zero-gap semimetals and polycrystalline Dirac semimetals with ultrahigh carrier mobility. We report the observation of positive and linear magnetoresistance in a single-crystalline semiconductor Bi2O2Se grown by chemical vapor deposition. Both Se-poor and Se-rich Bi2O2Se single-crystalline nanoplates display a linear magnetoresistance at high fields. The Se-poor Bi2O2Se exhibits a typical 2D conduction feature with a small effective mass of 0.032m0. The average transport Hall mobility, which is lower than 5500 cm2 V-1 s-1, is significantly reduced, compared with the ultrahigh quantum mobility as high as 16260 cm2 V-1 s-1. More interestingly, the pronounced Shubnikov-de Hass oscillations can be clearly observed from the very large and nearly linear magnetoresistance (>500% at 14 T and 2 K) in Se-poor Bi2O2Se. A close analysis of the results reveals that the large and linear magnetoresistance observed can be ascribed to the spatial mobility fluctuation, which is strongly supported by Fermi energy inhomogeneity in the nanoplate samples detected using an electrostatic force microscopy images and multiple frequencies in a Shubnikov-de Hass oscillation. On the contrary, the Se-rich Bi2O2Se exhibits a transport mobility (<300 cm2 V-1 s-1) much smaller than that observed in Se-poor samples and shows a much smaller linear magnetoresistance ratio (less than 150% at 14 T and 2 K). More strikingly, no Shubnikov-de Hass oscillations can be observed. Therefore, the linear magnetoresistance in Se-rich Bi2O2Se is governed by the average mobility rather than the mobility fluctuation.

14.
Plant Sci ; 290: 110293, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31779893

RESUMEN

Class I TGA transcription factors (TFs) are known to participate in plant resistance responses, however, their regulatory functions in the biosynthesis of secondary metabolites were rarely revealed. In this study, a class I TGA TF, TwTGA1, from Tripterygium wilfordii Hook.f. was cloned and characterized. Overexpression of TwTGA1 in T. wilfordii Hook.f. cells increased the production of triptolide and two sesquiterpene pyridine alkaloids, which was further enhanced by methyl jasmonate (MeJA) treatment. RNA interference of TwTGA1 showed no significant effects on the production of these metabolites, indicating the existence of other TGA partner(s) with overlapping functions. Heterologous expression of TwTGA1 in tobacco By-2 cells promoted the biosynthesis of pyridine alkaloids. Under the elicitation of MeJA, the contents of nonpyrrolidine alkaloids further increased but not for nicotine. TwTGA1 could induce the expression of Putrescine N-methyltransferase (PMT) and N-methylputrescine oxidase 1 (MPO1) through binding to their promoters. Finally, transient expression of TwTGA1 in leaves of Catharanthus roseus changed both the profiles of vinca alkaloids (increased contents of serpentine and catharanthine, but decreased that of vinblastine) and the expressions of biosynthesis-related genes. The metabolic and transcriptional data indicated a relationship between jasmonic acid signaling pathway and the functions of TwTGA1.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Factores de Transcripción/genética , Tripterygium/genética , Alcaloides/biosíntesis , Secuencia de Aminoácidos , Catharanthus/metabolismo , Diterpenos/metabolismo , Compuestos Epoxi/metabolismo , Fenantrenos/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Metabolismo Secundario , Alineación de Secuencia , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Tripterygium/metabolismo
15.
ACS Appl Mater Interfaces ; 11(51): 48230-48238, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31774651

RESUMEN

Microwave soft magnetic films (SMFs) are the key materials to effectively miniaturize and multifunctionalize the microwave electromagnetic components and devices. However, currently, single-layer SMFs encounter a frequency bottleneck at around 10 GHz. The ferromagnet/nonmagnetic spacer/ferromagnet sandwiched films with strong interlayer exchange coupling are possible solutions to break through that frequency limitation because they exhibit ultrahigh optical-mode (OM) resonance frequency frO up to 50 GHz, while the tiny permeability and the limited thickness are their own obstacles to overcome. In this study, biquadratic coupled FeCoB25nm/Ru0.25nm/FeCoB25nm sandwiched films with uniaxial magnetic anisotropy were deposited by a composition gradient sputtering method. Pure OM resonance with self-bias frO up to 18.21 GHz and a relative permeability µrO as high as 169 at the cut-off frequency was achieved. Moreover, both the frO and µrO remain unchanged in the magnetic field range of 0-80 Oe, indicating a strong anti-interference capability to small interference field. These results demonstrate that the biquadratic coupled OM resonance can solve the current frequency bottleneck of microwave SMFs by providing ultrahigh resonance frequency while maintaining considerable permeability, thus leading to potential applications of OM resonance in Ku-band microwave magnetic components.

16.
Nano Lett ; 19(8): 5739-5745, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31305077

RESUMEN

Materials that demonstrate large magnetoresistance have attracted significant interest for many decades. Extremely large tunnel magnetoresistance (TMR) has been reported by several groups across ultrathin CrI3 by exploiting the weak antiferromagnetic coupling between adjacent layers. Here, we report a comparative study of TMR in all three chromium trihalides (CrX3, X = Cl, Br, or I) in the two-dimensional limit. As the materials exhibit different transition temperatures and interlayer magnetic ordering in the ground state, tunneling measurements allow for an easy determination of the field-temperature phase diagram for the three systems. By changing sample thickness and biasing conditions, we then demonstrate how to maximize and further tailor the TMR response at different temperatures for each material. In particular, near the magnetic transition temperature, TMR is nonsaturating up to the highest fields measured for all three compounds owing to the large, field-induced exchange coupling.

17.
Proc Natl Acad Sci U S A ; 116(23): 11131-11136, 2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31110023

RESUMEN

We conduct a comprehensive study of three different magnetic semiconductors, CrI3, CrBr3, and CrCl3, by incorporating both few-layer and bilayer samples in van der Waals tunnel junctions. We find that the interlayer magnetic ordering, exchange gap, magnetic anisotropy, and magnon excitations evolve systematically with changing halogen atom. By fitting to a spin wave theory that accounts for nearest-neighbor exchange interactions, we are able to further determine a simple spin Hamiltonian describing all three systems. These results extend the 2D magnetism platform to Ising, Heisenberg, and XY spin classes in a single material family. Using magneto-optical measurements, we additionally demonstrate that ferromagnetism can be stabilized down to monolayer in more isotropic CrBr3, with transition temperature still close to that of the bulk.

18.
Biomed Pharmacother ; 113: 108655, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30849637

RESUMEN

In this study, we aimed to explore the expression profiles of some known functional lncRNAs in esophageal adenocarcinoma (EAD) and to screening the potential prognostic makers, using data from The Cancer Genome Atlas (TCGA)-esophageal carcinoma (ESCA). Results showed that DLEU2 is a high potential OS related marker among 73 functional lncRNAs. DLEU2 and its intronic miR-15a and miR-16-1 expression were significantly upregulated in EAD compared with adjacent normal tissues. However, miR-15a and miR-16-1 expression were only weakly correlated with DLEU2 expression. Univariate and multivariate analysis confirmed that DLEU2 expression, but not miR-15a or miR-16-1 expression is an independent prognostic marker in terms of OS (HR:1.688, 95%CI: 1.085-2.627, p = 0.020) in EAD patients. The exon 9 of DLEU2 is very strongly co-expressed with DLEU2 (Pearson's r = 0.96) and showed better predictive value than total DLEU2 expression in predicting the OS of EAD patients. Multivariate analysis confirmed its independent prognostic value (HR:1.970, 95%CI: 1.266-3.067, p = 0.003), after adjustment of histologic grade, pathological stages and the presence of residual tumor. By checking the methylation status of DLEU2 gene, we excluded the possibility of the influence of two CpG sites near the DLEU2 exon 9 locus on its expression. In addition, although copy number alterations (CNAs) were observed DLEU2 gene, heterozygous loss (-1), low-level copy gain (+1) and high-level amplification (+2) had no significant association with DLEU2 transcription. Based on these findings, we infer that DLEU2 exon 9 expression might serve as a valuable biomarker of unfavorable OS in EAD patients.


Asunto(s)
Adenocarcinoma/metabolismo , Biomarcadores de Tumor/biosíntesis , Neoplasias Esofágicas/metabolismo , Exones/genética , ARN Largo no Codificante/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Islas de CpG/genética , Epigénesis Genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidad , Femenino , Humanos , Modelos Lineales , Masculino , Pronóstico , ARN Largo no Codificante/genética , Análisis de Supervivencia , Transferasas , Proteínas Supresoras de Tumor/genética , Regulación hacia Arriba
19.
Onco Targets Ther ; 11: 4001-4017, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30034240

RESUMEN

INTRODUCTION: Microfibril-associated protein 2 (MFAP2) is an extracellular matrix protein that interacts with fibrillin to modulate the function of microfibrils. MFAP2 has been reported to play a significant role in obesity, diabetes, and osteopenia, and has been shown to be upregulated in head and neck squamous cell carcinoma. However, the molecular function and prognostic value of MFAP2 have never been reported in gastric cancer (GC) or any other tumors. METHODS: The current study investigated the expression patterns, prognostic significance, functional role, and possible mechanisms of MFAP2 in GC. RESULTS: We demonstrated that MFAP2 was overexpressed in GC tissues, and its overexpression was significantly correlated with poor overall and disease-free survival in patients with GC. Moreover, we found that MFAP2 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) phenotype in GC cells. MFAP2 might modulate EMT of GC cells by activating the TGF-ß/SMAD2/3 signaling pathway. CONCLUSION: These findings provide novel evidence that MFAP2 plays a crucial role in the progression of GC. Therefore, MFAP2 may be a promising prognostic marker and a potent anticancer agent.

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