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1.
Nano Lett ; 24(34): 10547-10553, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39140754

RESUMEN

Two-dimensional transition metal carbides/nitrides (MXenes) have shown great promise in various applications. However, mass production of MXenes suffers from the excessive use of toxic fluorine-containing reagents. Herein, a new method was validated for synthesizing MXenes from five MAX ceramics. The method features a minimized (stoichiometric) dosage of F-containing reagent (NaBF4) and polyols (glycerol, erythritol, and xylitol) as the reaction solvent. Due to the sweetness of polyols and the low environmental impact, we refer to this method as a "sweet" synthesis of MXenes. An in-depth molecular dynamics simulation study, combined with experimental kinetic parameters, further revealed that the diffusion of F- in the confined interplanar space is rate-determining for the etching reaction. The expansion of interlayer spacing by polyols effectively reduces the diffusion activation energy of F- and accelerates the etching reaction.

2.
Small ; 20(29): e2311631, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38513241

RESUMEN

Nanoparticles composed of high-entropy alloys (HEA NPs) exhibit remarkable performance in electrocatalytic processes such as hydrogen evolution and oxidations. In this study, two types of quinary HEA NPs of PtRhPdIrRu, are synthesized, featuring disordered and crystallized nanostructures, both with and without a boiling mixture. The disordered HEA NPs (d-HEA NPs) with a size of 3.5 nm is synthesized under intense boiling conditions, attributed to improved heat and mass transfer during reduction of precursors and particle growth. The disordered HEA NPs displayed an exceptionally high turnover frequency of 33.1 s-1 at an overpotential of 50 mV, surpassing commercial Pt NPs in acidic electrolytes by 5.4 times. Additionally, d-HEA NPs exhibited superior stability at a constant electrolyzing current of 50 mA cm-2 compared to commercial Pt NPs. When employed as the anodic catalyst in an H2-O2 fuel cell, d-HEA NPs demonstrated a remarkable high current power density of 15.3 kW per gram of noble metal. Consequently, these findings highlight the potential of d-HEA NPs in electrochemical applications involving hydrogen.

3.
J Environ Manage ; 365: 121591, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38941856

RESUMEN

Understanding the relationships between ecosystem services (ES) and the factors driving their changes over long periods and multiple scales is key for landscape managers in decision-making. However, the widespread implementation of restoration programs has led to significant ES changes, with trade-offs across space and time that have been little explored empirically, making it challenging to provide effective experience for managers. We quantified changes and interactions among five ES across various stages of the Grain-to-Green Program in the eastern Loess Plateau, examining these dynamics at threefold spatial scales. We observed notable increases in soil retention and Net Ecosystem Production but declines in habitat quality and Landscape aesthetics under afforestation. Over time, and with more integrated restoration strategies, synergies between ES pairs weakened, and non-correlations (even trade-offs) increased. To avoid unnecessary trade-offs, we recommend incorporating socio-ecological factors driving ES changes and ES bundles, informed by empirical experience, into proactive spatial planning and environmental management strategies for multi-ES objectives. The temporal lags and spatial trade-offs highlighted by this study offer crucial insights for large-scale restoration programs worldwide.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ecología , Suelo , Restauración y Remediación Ambiental
4.
J Chem Phys ; 158(4): 041101, 2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36725517

RESUMEN

Metal-free catalysts are made by the elements with infinite reserve in nature and, therefore, show the potential for large-scale applications in energy devices including metal-air batteries. The construction of metal-air batteries prefers using self-supporting catalysts with favorable activity as well as fast kinetics. However, it is challenging due to the limited electropositivity of metal-free catalysts for O-O bond formation in oxygen evolution reaction (OER), scaling relationship restrictions between OER and oxygen reduction reaction, and difficulty in porosity construction on the monolith electrode surface. In this contribution, through developing a facile methodology of quenching high-temperature carbon clothes in liquid nitrogen, a self-supported carbon cloth with bifunctional active graphene skin and fast kinetics is well constructed to serve as the air cathode in metal-air batteries. Regulated oxygen species and three-dimensionally hierarchical porosity are well constructed on the carbon fiber surfaces, contributing high intrinsic activity and prominently enhanced kinetics, which leads to favorable performances in aqueous as well as flexible rechargeable zinc-air batteries. The work proposed a promising strategy in the rational design and smart synthesis of fast-kinetic monolith electrodes, which refreshes concepts and strategies of advanced material fabrication, and also bridges material science and practical energy devices.

5.
Genomics ; 114(2): 110265, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35032618

RESUMEN

DNA N6-methyladenine (6 mA) is a new type of DNA methylation identified in various eukaryotic cells. However, its alteration and genomic distribution features in hepatocellular carcinoma (HCC) remain elusive. In this study, we found that N6AMT1 overexpression increased HCC cell viability, suppressed apoptosis, and enhanced migration and invasion, whereas ALKBH1 overexpression induced the opposite effects. Further, 23,779 gain-of-6 mA regions and 11,240 loss-of-6 mA regions were differentially identified in HCC tissues. The differential gain and loss of 6 mA regions were considerably enriched in intergenic regions. Moreover, 7% of the differential 6 mA modifications were associated with tumors, with 60 associated with oncogenes and 57 with tumor suppressor genes (TSGs), and 17 were common to oncogenes and TSGs. The candidate genes affected by 6 mA were filtered by gene ontology (GO) and RNA-seq. Using quantitative polymerase chain reaction (qPCR), BCL2 and PARTICL were found to be correlated with DNA 6 mA in certain HCC processes.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Histona H2a Dioxigenasa, Homólogo 1 de AlkB/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , ADN/metabolismo , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Genoma , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/genética , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/metabolismo
6.
Angew Chem Int Ed Engl ; 62(43): e202311909, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37671744

RESUMEN

Metal-organic frameworks (MOFs) have been increasingly applied in oxygen evolution reaction (OER), and the surface of MOFs usually undergoes structural transformation to form metal oxyhydroxides to serve as catalytically active sites. However, the controllable regulation of the reconstruction process of MOFs remains as a great challenge. Here we report a defect engineering strategy to facilitate the structural transformation of MOFs to metal oxyhydroxides during OER with enhanced activity. Defective MOFs (denoted as NiFc'x Fc1-x ) with abundant unsaturated metal sites are constructed by mixing ligands of 1,1'-ferrocene dicarboxylic acid (Fc') and defective ferrocene carboxylic acid (Fc). NiFc'x Fc1-x series are more prone to be transformed to metal oxyhydroxides compared with the non-defective MOFs (NiFc'). Moreover, the as-formed metal oxyhydroxides derived from defective MOFs contain more oxygen vacancies. NiFc'Fc grown on nickel foam exhibits excellent OER catalytic activity with an overpotential of 213 mV at the current density of 100 mA cm-2 , superior to that of undefective NiFc'. Experimental results and theoretical calculations suggest that the abundant oxygen vacancies in the derived metal oxyhydroxides facilitate the adsorption of oxygen-containing intermediates on active centers, thus significantly improving the OER activity.

7.
Small ; 18(22): e2201391, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35523724

RESUMEN

Single-atom sites can not only act as active centers, but also serve as promising catalyst regulators and/or promoters. However, in many complex reaction systems such as electrochemical CO2 reduction reaction (CO2 RR), the introduction of single-atom regulators may inevitably induce the competitive hydrogen evolution reaction (HER) and thus reduce the selectivity. Here, the authors demonstrate that introducing HER-inert main-group metal single atoms adjacent to transition-metal single atoms can modify their electronic structure to enhance the CO2 RR to CO without inducing the HER side reaction. Dual-metal Cu and In single-site atoms anchored on mesoporous nitrogen-doped carbon (denoted as Cu-In-NC) are prepared by the pyrolysis of a multimetallic metal-organic framework. Cu-In-NC shows a high faradic efficiency of 96% toward CO formation at -0.7 V versus reversible hydrogen electrode, superior to that of its monometallic single-atom counterparts. Density functional theory studies reveal that the HER-inert In sites can activate the adjacent Cu sites through electronic modifications, strengthening the binding of *COOH intermediate and thus boosting the electrochemical reduction of CO2 to CO.


Asunto(s)
Dióxido de Carbono , Elementos de Transición , Dióxido de Carbono/química , Catálisis , Hidrógeno , Metales/química
8.
Arch Toxicol ; 96(7): 2097-2111, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35396937

RESUMEN

Mesothelin (MSLN) is a cell surface protein associated with tumor invasion and metastasis. This study aims to explore the biological function of MSLN in gastric cancer and to evaluate the association of MSLN polymorphism (rs3764247, rs3764246, rs12597489, rs1057147, rs3765319) with the risk and prognosis of gastric cancer. Small interfering RNA (siRNA) transfection and MSLN overexpression were performed in human gastric cancer cell lines, respectively. The proliferation of tumor cells was evaluated by Cell counting kit 8(CCK-8) and colony formation assay. Wound healing assay and transwell assay were used to elucidate gastric cancer cell migration and invasion rates. We conducted a case-control study involving 860 patients with gastric cancer and 870 controls. All mutation sites were genotyped by PCR-LDR sequencing. First, our study revealed the cancer-promoting role of MSLN in gastric cancer. Second, we also demonstrated that rs3764247 and rs3764246 were associated with a reduced risk of gastric cancer (OR = 0.83, p = 0.010; OR = 0.84, p = 0.011; respectively). The clinicopathological analysis further showed that rs3764247 was closely related to T stage, vascular infiltration, and HER2 expression. In addition, in the survival analysis of 392 patients with gastric cancer, patients with rs3764247 CC genotype had poorer survival than patients with AA + AC genotype after adjusting for age, sex, TNM stage, and Lauren classification (HR = 2.07, p = 0.029). Our findings indicated that MSLN could be an oncogene whose polymorphisms were closely related to the risk and prognosis of gastric cancer.


Asunto(s)
Neoplasias Gástricas , Estudios de Casos y Controles , Línea Celular Tumoral , China , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Humanos , Mesotelina , Oncogenes , Pronóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología
9.
Nano Lett ; 21(8): 3640-3648, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33848169

RESUMEN

The pyrolysis of metal-organic frameworks (MOFs) is an ingenious way to synthesize carbon-based materials with unique morphology for various applications including electrocatalysis. In this work, we reported a facile morphology regulation strategy for the synthesis of a spherical superstructure of MOF nanosheets. The use of metal hydroxide nanosheets on Zn particles as precursors/templates allowed MOFs with general polyhedron shape to form nanosheets and assemble into a spherical superstructure in the ligand solution. Further, a hollow spherical superstructure of carbon nanosheets decorated with metal-based nanoparticles was fabricated through the pyrolysis of MOF nanosheet superstructures at 950 °C, where the substrate/template Zn particle cores were evaporated away. The obtained composites possess carbon-based superstructures with abundant mesopores and metal-based nanoparticles with rich alloy/oxide interfaces. These features endow this MOF-derived carbon-based material with outstanding bifunctional activity for oxygen reduction/evolution reactions and great performances in Zn-air batteries.

10.
Cancer Immunol Immunother ; 70(4): 1015-1029, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33104837

RESUMEN

BACKGROUND: CKLF-like MARVEL transmembrane domain-containing 6 (CMTM6) is a critical regulator of tumor immunology among various cancers. However, the role and underlying molecular mechanism of CMTM6 in oral squamous cell carcinoma (OSCC) progression remains unclear. METHODS: The expression of CMTM6, PD-L1 and CD163 in OSCC tissues were detected by immunohistochemistry on tissue microarray. The effect of CMTM6 knockdown on OSCC cells and macrophage polarization were analyzed by CCK-8 assay, apoptotic assay, would-healing assay, transwell assay and qPCR. OSCC cell derived exosomes were obtained by ultracentrifugation and the mechanistic studies were conducted by qPCR and Western Blot. 4-Nitroquinoline N-oxide (4NQO) induced OSCC mice were used for verifying the effect of CMTM6 downregulation on M2 macrophage infiltration and tumor growth. RESULTS: In OSCC samples, higher CMTM6 expression has been obviously associated with higher pathological stage of OSCC patients, CD163 + macrophages infiltration and PD-L1 expression. CMTM6 knockdown of OSCC cells inhibited proliferative, migrative and invasive abilities of OSCC cells, as well as inhibited M2 macrophage polarization in vitro with downregulating PD-L1 expression. Importantly, exosomes from OSCC cells shuttled CMTM6 to macrophages and promoted M2-like macrophage polarization through activating ERK1/2 signaling. In addition, in 4NQO-induced OSCC mice, CMTM6 level was positively associated with CD163, CD206 and PD-L1 as well as M2-like macrophage infiltration. CONCLUSION: OSCC cell-secreted exosomal CMTM6 induces M2-like macrophages polarization to promote malignant progression via ERK1/2 signaling pathway, revealing a novel crosstalk between cancer cells and immune cells in OSCC microenvironment.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Exosomas/metabolismo , Proteínas con Dominio MARVEL/metabolismo , Activación de Macrófagos/inmunología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neoplasias de la Boca/patología , Proteínas de la Mielina/metabolismo , Animales , Apoptosis , Biomarcadores de Tumor/genética , Movimiento Celular , Proliferación Celular , Exosomas/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas con Dominio MARVEL/genética , Ratones , Ratones Endogámicos C57BL , Proteína Quinasa 1 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Neoplasias de la Boca/inmunología , Neoplasias de la Boca/metabolismo , Proteínas de la Mielina/genética , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Células Tumorales Cultivadas , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Hum Reprod ; 36(12): 3049-3061, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34647126

RESUMEN

STUDY QUESTION: Is the protein l-arginine methyltransferase 3 (PRMT3)/asymmetrical dimethylarginine (ADMA)/nitric oxide (NO) pathway involved in the development of recurrent miscarriage (RM), and what is the potential mechanism? SUMMARY ANSWER: Elevated levels of PRMT3 and ADMA inhibit NO formation in the decidua, thereby impairing the functions of trophoblast cells at the maternal-foetal interface. WHAT IS KNOWN ALREADY: Decreased NO bioavailability is associated with RM. ADMA, an endogenous inhibitor of nitric oxide synthase (NOS), is derived from the methylation of protein arginine residues by PRMTs and serves as a predictor of mortality in critical illness. STUDY DESIGN, SIZE, DURATION: A total of 145 women with RM and 149 healthy women undergoing elective termination of an early normal pregnancy were enrolled. Ninety-six female CBA/J, 24 male DBA/2 and 24 male BALB/c mice were included. CBA/J × DBA/2 matings represent the abortion group, while CBA/J × BALB/c matings represent the normal control group. The CBA/J pregnant mice were then categorised into four groups: (i) normal + vehicle group (n = 28), (ii) abortion + vehicle group (n = 28), (iii) normal + SGC707 (a PRMT3 inhibitor) group (n = 20) and (iv) abortion + SGC707 group (n = 20). All injections were made intraperitoneally on Days 0.5, 3.5 and 6.5 of pregnancy. Decidual tissues were collected on Days 8.5, 9.5 and 10.5 of gestation. The embryo resorption rates were calculated on Day 9.5 and Day 10.5 of gestation. PARTICIPANTS/MATERIALS, SETTING, METHODS: NO concentration, ADMA content, NOS activity, expression levels of NOS and PRMTs in decidual tissues were determined using conventional assay kits or western blotting. PRMT3 expression was further analysed in decidual stromal cells, macrophages and natural killer cells. A co-culture system between decidual macrophages (DMs) and HTR-8/SVneo trophoblasts was constructed to study the roles of the PRMT3/ADMA/NO signalling pathway. Trophoblast apoptosis was analysed via Annexin V-fluorescein isothiocyanate/propidium iodide staining. CBA/J × DBA/2 mouse models were used to investigate the effects of SGC707 on embryo resorption rates. MAIN RESULTS AND THE ROLE OF CHANCE: Our results show that NO concentration and NOS activity were decreased, but ADMA content and PRMT3 expression were increased in the decidua of RM patients. Moreover, compared with the normal control subjects, PRMT3 expression was significantly up-regulated in the macrophages but not in the natural killer cells or stromal cells of the decidua from RM patients. The inhibition of PRMT3 results in a significant decrease in ADMA accumulation and an increase in NO concentration in macrophages. When co-cultured with DMs, which were treated with SGC707 and ADMA, trophoblast apoptosis was suppressed and induced, respectively. In vivo experiments revealed that the administration of SGC707 reduced the embryo resorption rate of CBA/J × DBA/2 mice. LIMITATIONS, REASONS FOR CAUTION: All sets of experiments were not performed with the same samples. The main reason is that each tissue needs to be reserved for clinical diagnosis and only a small piece of each tissue can be cut and collected for this study. WIDER IMPLICATIONS OF THE FINDINGS: Our results indicate that the PRMT3/ADMA/NO pathway is a potential marker and target for the clinical diagnosis and therapy of RM. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Key Research and Development Program of China (2017YFC1001401), National Natural Science Foundation of China (81730039, 82071653, 81671460, 81971384 and 82171657) and Shanghai Municipal Medical and Health Discipline Construction Projects (2017ZZ02015). The authors have declared no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Aborto Habitual , Arginina , Macrófagos , Óxido Nítrico , Proteína-Arginina N-Metiltransferasas/metabolismo , Trofoblastos , Aborto Habitual/metabolismo , Animales , Apoptosis , Arginina/análogos & derivados , Arginina/metabolismo , China , Decidua/metabolismo , Femenino , Humanos , Péptidos y Proteínas de Señalización Intracelular , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos CBA , Ratones Endogámicos DBA , Óxido Nítrico/metabolismo , Embarazo , Trofoblastos/metabolismo
12.
Chem Soc Rev ; 49(5): 1414-1448, 2020 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-32039429

RESUMEN

Oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are three key reactions for the development of green and sustainable energy systems. Efficient electrocatalysts for these reactions are highly desired to lower their overpotentials and promote practical applications of related energy devices. Metal-organic frameworks (MOFs) have recently emerged as precursors to fabricate carbon-based electrocatalysts with high electrical conductivity and uniformly distributed active sites. In this review, the current progress of MOF-derived carbon-based materials for ORR/OER/HER electrocatalysis is presented. Materials design strategies of MOF-derived carbon-based materials are firstly summarized to show the rich possibilities of the morphology and composition of MOF-derived carbon-based materials. A wide range of applications based on these materials for ORR, OER, HER and multifunctional electrocatalysis are discussed, with an emphasis on the required features of MOF-derived carbon-based materials for the electrocatalysis of corresponding reactions. Finally, perspectives on the development of MOF-derived carbon-based materials for ORR, OER and HER electrocatalysis are provided.

13.
J Hepatol ; 73(4): 906-917, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32407813

RESUMEN

BACKGROUND & AIMS: Neutrophils are one of the most abundant components in human hepatocellular carcinoma (HCC) and have been shown to play important roles in regulating disease progression. However, neutrophils are very short-lived cells in circulation, and mechanisms regulating their accumulation and functions in HCC are not yet fully understood. METHODS: Monocytes were purified from non-tumor or paired tumor tissues of patients with HCC, and their production of neutrophil-attracting chemokines was evaluated. Mechanisms regulating the expression of CXCL2/8 by tumor monocytes, and the role of tumor monocyte-derived chemokines and cytokines in modulating neutrophil accumulation and functions were studied with both ex vivo analyses and in vitro experiments. RESULTS: Monocyte-derived CXCL2 and CXCL8 were major factors in regulating the recruitment of neutrophils into tumor milieus. These chemokines, in addition to tumor-derived soluble factors, could inhibit apoptosis and sustain survival of neutrophils, thus leading to neutrophil accumulation in tumor tissues. Moreover, monocyte-derived TNF-α acted synergistically with tumor-derived soluble factors to induce the production of the pro-metastasis factor OSM by neutrophils. Further, the glycolytic switch in tumor-infiltrating monocytes mediated their production of CXCL2 and CXCL8 via the PFKFB3-NF-κB signaling pathway. Accordingly, levels of PFKFB3, CXCL2/CXCL8 production in monocytes and infiltration of OSM-producing neutrophils were positively correlated in human HCC tissues. CONCLUSIONS: Our results unveiled a previously unappreciated link between monocytes and neutrophils in human HCC, identifying possible targets that could be therapeutically exploited in the future. LAY SUMMARY: Neutrophils constitute a major but poorly understood component of human hepatocellular carcinoma (HCC). Herein, we unveil a novel mechanism by which metabolic switching in monocytes promotes the accumulation of neutrophils in the tumors of patients with HCC. Both monocyte-produced chemokines and signals from the tumor microenvironment promote the production of the pro-metastatic factor OSM by neutrophils. These data identify potential targets for immune-based anticancer therapies for HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Glucólisis/fisiología , Neoplasias Hepáticas/metabolismo , Monocitos/metabolismo , Neutrófilos/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Monocitos/patología , Neutrófilos/patología , Estudios Retrospectivos , Transducción de Señal
14.
Small ; 16(15): e1905240, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31755227

RESUMEN

Microbial fuel cells (MFCs) can convert organics in wastewater directly to electricity, and improving oxygen reduction reaction (ORR) performance is critical to their development and future applications. Electrocatalytic ORR performance is determined by the intrinsic activity and accessible amounts of active sites. A surface nitrogen-enriched carbon coaxial nanocable (NCCN) is applied as an ORR electrocatalyst and combined with activated carbon (AC) with 80 wt% addition as a carbon-carbon composite air cathode in MFCs. The fully exposed nitrogen active sites of NCCN contribute to the enhanced ORR activity, while the graphitized core affords a rapid pathway for electron transportation. AC serves as a spacer to construct a porous framework with interconnected ion diffusion channels. This cathode thus exhibits a maximum power density of 2090 mW m-2 , 120% higher than commercial Pt/C electrocatalysts, and also 6% higher than the pure NCCN, indicating a synergistic effect between NCCN and AC. A high-performance NCCN-AC air cathode with a great promise for future MFC applications is reported and an effective strategy to bridge the electrocatalytic performance from nanomaterials to practical devices is presented.

15.
Biol Reprod ; 102(3): 524-531, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-31742319

RESUMEN

Recurrent spontaneous abortion (RSA) is one of the major pregnancy disorders and poses a serious risk to both the mother and the fetus. Although a number of research efforts have been conducted, therapeutic advances for treating RSA have not lived up to their expectations. Hence, other treatments should be explored. The important role of natural killer (NK) cells in immunotherapy is attracting increasing attention, both as a pharmaceutical target and for cell therapies. NK cells are abundant in the endometrium and play a role in implantation and placentation in normal pregnancy. As research progresses, NK cells are increasingly regarded as playing essential roles in the emergence and development of RSA. In this article, I review recent findings on the role of uterine NK cells in the pathophysiology of RSA. These cells may become therapeutic NK cell-related targets. In conclusion, although several issues regarding NK cells in RSA remain unresolved and require further investigation, extensive evidence is available for the treatment of RSA.


Asunto(s)
Aborto Habitual/inmunología , Implantación del Embrión/inmunología , Endometrio/inmunología , Células Asesinas Naturales/inmunología , Placentación/inmunología , Animales , Femenino , Humanos , Embarazo
16.
Mol Hum Reprod ; 26(7): 521-531, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32433749

RESUMEN

Recurrent spontaneous miscarriage (RSM) is a systemic disorder that has been defined as two or more pregnancies lost before the 20th week of gestation. Although the impaired function of macrophages at the maternal-fetal interface has been reported to be associated with RSM, the underlying mechanisms have not been fully elucidated. Here, we revealed that HDAC8 plays a critical role in RSM. Our results show that the mRNA and protein expression of HDAC8 was decreased in decidual macrophages from RSM patients. Moreover, the knockdown of HDAC8 resulted in a significant decrease in CD163 expression and an increase in apoptosis in dTHP-1 macrophages. Mechanistically, the ERK signaling pathway was activated in HDAC8-knockdown macrophages. When HDAC8-knockdown cells were pretreated with the ERK inhibitor U0126, expression levels of CD163, activated caspases 3, 7 and 9, and the apoptosis rate, were rescued. Taken together, our current results suggest that HDAC8 plays an important role in macrophage activation and apoptosis and may contribute to maintaining normal pregnancy by increasing the expression of M2 marker genes and inhibiting the apoptosis of macrophages at the maternal-fetal interface.


Asunto(s)
Aborto Habitual/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Apoptosis/fisiología , Histona Desacetilasas/metabolismo , Macrófagos/citología , Macrófagos/metabolismo , Receptores de Superficie Celular/metabolismo , Proteínas Represoras/metabolismo , Transducción de Señal/fisiología , Aborto Habitual/genética , Antígenos CD/genética , Antígenos de Diferenciación Mielomonocítica/genética , Apoptosis/genética , Histona Desacetilasas/genética , Humanos , Receptores de Superficie Celular/genética , Proteínas Represoras/genética , Transducción de Señal/genética , Células THP-1
17.
Exp Cell Res ; 384(2): 111634, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31541617

RESUMEN

Great attention has been attached to explore the association between oral bacteria and oral cancer. Recently, four common inhabitants of oral cavity, Porphyromonas gingivalis, Fusobacterium nucleatum, Treponema denticola and Streptococcus anginosus, have been identified as potential etiologic bacterial agents for oral carcinogenesis. They might promote the oncogenesis and progression of oral cancer by induction of chronic inflammation, enhancement of migration and invasiveness, inhibition of cell apoptosis, augment of cell proliferation, suppression of immune system and production of carcinogenic substances. Thus, this review will focus on the possible mechanisms of these oral bacteria contributing to occurrence and development of oral cancer, and the potential clinical implications of utilizing oral bacteria on the diagnosis, prevention and treatment of oral cancer will be discussed.


Asunto(s)
Neoplasias de la Boca/inmunología , Neoplasias de la Boca/microbiología , Animales , Bacterias/inmunología , Carcinogénesis/inmunología , Proliferación Celular/fisiología , Humanos , Oncogenes/inmunología
18.
J Cell Mol Med ; 23(10): 6942-6954, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31368152

RESUMEN

The enhancer of zeste homolog 2 (EZH2), known as a member of the polycomb group (PcG) proteins, is an oncogene overexpressed in a variety of human cancers. Here, we found that EZH2 correlated with poor survival of oral squamous cell carcinoma (OSCC) patients using immunohistochemistry staining. EZH2 overexpression led to a significant induction in tumour glycolysis, Epithelial-mesenchymal transition (EMT), migration and invasion of OSCC cells. Conversely, silencing of EZH2 inhibited tumour glycolysis, EMT, migration and invasion in OSCC cells. Ectopic overexpression of EZH2 increased phosphorylation of STAT3 at pY705 and decreased FoxO1 expression, and FoxO1 expression was enhanced when inhibiting STAT3. In addition, EZH2 overexpression led to a significant decrease in FoxO1 mRNA levels in nude mice xenograft. These results indicated that regulation of EZH2 might have the potential to be targeted for OSCC treatment.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Proteína Forkhead Box O1/metabolismo , Glucólisis , Neoplasias de la Boca/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Animales , Carcinoma de Células Escamosas/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular , Regulación hacia Abajo/genética , Transición Epitelial-Mesenquimal/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Análisis Multivariante , Invasividad Neoplásica , Fosforilación , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Supervivencia
19.
Mol Carcinog ; 58(6): 898-912, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30667094

RESUMEN

Macrophage migration inhibitory factor (MIF) is a prominent orchestrator during the onset and progression of cancer. Recently, MIF was detected in salivary adenoid cystic carcinoma (SACC). However, its functional effect in perineural invasion (PNI) of SACC remained unknown. To illuminate the effect of MIF in genesis of PNI in SACC, we examined the expression of MIF, epithelial-to-mesenchymal transition (EMT)-related markers, and Schwann cell markers by immunohistochemical analysis in 158 cases of SACC samples. Meanwhile, the correlation between MIF and PNI of SACC species was analyzed. Our data indicated that MIF expression was associated with PNI of SACC significantly. In vitro, the silence and overexpression experiments of MIF were performed in SACC cell lines. The ability of migration, invasion and PNI could be inhibited significantly by siRNA-mediated MIF silence, and the occurrence of EMT and Schwann-like cell differentiation was also inhibited by MIF silence in SACC-LM cells. Overexpression of MIF in SACC-83 cells using expressive plasmid showed the opposite effects. Our findings identified that an association between PNI and MIF expression existed. MIF may promote PNI of SACC by participating in cytoskeletal reorganization and pseudo foot formation induced by EMT and the Schwann-like cell differentiation of SACC cells.


Asunto(s)
Carcinoma Adenoide Quístico/patología , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Neoplasias de las Glándulas Salivales/patología , Células de Schwann/citología , Carcinoma Adenoide Quístico/metabolismo , Diferenciación Celular , Línea Celular Tumoral , Movimiento Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Oxidorreductasas Intramoleculares/genética , Factores Inhibidores de la Migración de Macrófagos/genética , Invasividad Neoplásica , Neoplasias de las Glándulas Salivales/metabolismo , Células de Schwann/patología
20.
Acc Chem Res ; 51(4): 881-889, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29384364

RESUMEN

Various gas-involving energy electrocatalysis, including oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER), has witnessed increasing concerns recently for the sake of clean, renewable, and efficient energy technologies. However, these heterogeneous reactions exhibit sluggish kinetics due to multistep electron transfer and only occur at triple-phase boundary regions. Up to now, tremendous attention has been attracted to develop cost-effective and high-performance electrocatalysts to boost the electrocatalytic activities as promising alternatives to noble metal counterparts. In addition to the prolific achievements in materials science, the advances in interface chemistry are also very critical in consideration of the complex phenomena proceeded at triple-phase boundary regions, such as mass diffusion, electron transfer, and surface reaction. Therefore, insightful principles and effective strategies for a comprehensive optimization, ranging from active sites to electrochemical interface, are necessary to fully enhance the electrocatalytic performance aiming at practical device applications. In this Account, we give an overview of our recent attempts toward efficient gas-involving electrocatalysis with multiscale principles from the respect of electronic structure, hierarchical morphology, and electrode interface step by step. It is widely accepted that the intrinsic activity of individual active sites is directly influenced by their electronic structure. Heteroatom doping and topological defects are demonstrated to be the most effective strategies for metal-free nanocarbon materials, while the cationic (e.g., Ni, Fe, Co, Sn) and anionic (e.g., O, S, OH) regulation is revealed to be a promising method for transition metal compounds, to alter the electronic structure and generate high activity. Additionally, the apparent activity of the whole electrocatalyst is significantly impacted by its hierarchical morphology. The active sites of nanocarbon materials are expected to be enriched on the surface for a full exposure and utilization; the hybridization of other active components with nanocarbon materials should achieve a uniform dispersion in nanoscale and a strongly coupled interface, thereby ensuring the electron transfer and boosting the activity. Furthermore, steady and favorable electrochemical interfaces are strongly anticipated in working electrodes for optimal reaction conditions. The powdery electrocatalysts are suggested to be constructed into self-supported electrodes for more efficient and stable catalysis integrally, while the local microenvironment can be versatilely modified by ionic liquids with more beneficial gas solubility and hydrophobicity. Collectively, with the all-round regulation of the electronic structure, hierarchical morphology, and electrode interface, the electrocatalytic performances are demonstrated to be comprehensively facilitated. Such multiscale principles stemmed from the in-depth insights on the structure-activity relationship and heterogeneous reaction characteristics will no doubt pave the way for the future development of gas-involving energy electrocatalysis, and also afford constructive inspirations in a broad range of research including CO2 reduction reaction, hydrogen peroxide production, nitrogen reduction reaction, and other important electrocatalytic activation of small molecules.

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