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Flowering plants have evolved numerous intraspecific and interspecific prezygotic reproductive barriers to prevent production of unfavourable offspring1. Within a species, self-incompatibility (SI) is a widely utilized mechanism that rejects self-pollen2,3 to avoid inbreeding depression. Interspecific barriers restrain breeding between species and often follow the SI × self-compatible (SC) rule, that is, interspecific pollen is unilaterally incompatible (UI) on SI pistils but unilaterally compatible (UC) on SC pistils1,4-6. The molecular mechanisms underlying SI, UI, SC and UC and their interconnections in the Brassicaceae remain unclear. Here we demonstrate that the SI pollen determinant S-locus cysteine-rich protein/S-locus protein 11 (SCR/SP11)2,3 or a signal from UI pollen binds to the SI female determinant S-locus receptor kinase (SRK)2,3, recruits FERONIA (FER)7-9 and activates FER-mediated reactive oxygen species production in SI stigmas10,11 to reject incompatible pollen. For compatible responses, diverged pollen coat protein B-class12-14 from SC and UC pollen differentially trigger nitric oxide, nitrosate FER to suppress reactive oxygen species in SC stigmas to facilitate pollen growth in an intraspecies-preferential manner, maintaining species integrity. Our results show that SRK and FER integrate mechanisms underlying intraspecific and interspecific barriers and offer paths to achieve distant breeding in Brassicaceae crops.
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Brassicaceae , Flores , Hibridização Genética , Proteínas de Plantas , Polinização , Brassicaceae/genética , Brassicaceae/metabolismo , Depressão por Endogamia , Óxido Nítrico/metabolismo , Fosfotransferases/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Pólen/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Especificidade da Espécie , Flores/metabolismo , AutofertilizaçãoRESUMO
The incidence of nasopharyngeal carcinoma (NPC) exhibits significant variations across different ethnic groups and geographical regions, with Southeast Asia and North Africa being endemic areas. Of note, Epstein-Barr virus (EBV) infection is closely associated with almost all of the undifferentiated NPC cases. Over the past three decades, radiation therapy and chemotherapy have formed the cornerstone of NPC treatment. However, recent advancements in immunotherapy have introduced a range of promising approaches for managing NPC. In light of these developments, it has become evident that a deeper understanding of the tumor microenvironment (TME) is crucial. The TME serves a dual function, acting as a promoter of tumorigenesis while also orchestrating immunosuppression, thereby facilitating cancer progression and enabling immune evasion. Consequently, a comprehensive comprehension of the TME and its intricate involvement in the initiation, progression, and metastasis of NPC is imperative for the development of effective anticancer drugs. Moreover, given the complexity of TME and the inter-patient heterogeneity, personalized treatment should be designed to maximize therapeutic efficacy and circumvent drug resistance. This review aims to provide an in-depth exploration of the TME within the context of EBV-induced NPC, with a particular emphasis on its pivotal role in regulating intercellular communication and shaping treatment responses. Additionally, the review offers a concise summary of drug resistance mechanisms and potential strategies for their reversal, specifically in relation to chemoradiation therapy, targeted therapy, and immunotherapy. Furthermore, recent advances in clinical trials pertaining to NPC are also discussed.
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Infecções por Vírus Epstein-Barr , Neoplasias Nasofaríngeas , Humanos , Infecções por Vírus Epstein-Barr/complicações , Carcinoma Nasofaríngeo/tratamento farmacológico , Microambiente Tumoral , Herpesvirus Humano 4 , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genéticaRESUMO
Autoimmunity contributes to the pathogenesis of viral myocarditis (VMC), which is characterized by the production of anti-heart autoantibodies (AHA) from lymphoid follicles. Recently, the formation of ectopic lymphoid follicles (ELFs) was reported in heart grafts. However, the existence and role of ELFs in myocardial tissues of VMC remain unclear. This study aimed to explore whether and how cardiac ELFs with germinal centers (GCs) could be generated during the development of VMC. We identified the existence of ELFs and explored the underlying mechanism. In a BALB/c mouse model of VMC, the dynamic myocardial infiltrations of lymphocytic aggregates and expressions of associated lymphorganogenic factors were investigated, accompanied by the detection of the production and location of myocardial AHA. The data indicated ELFs formation in myocardial tissues of VMC, and the number of ELFs was in accordance with the severity of VMC. Moreover, the functional ELFs with GCs were capable of facilitating the production of local AHA. Blocking IL-17 or podoplanin (PDPN) could inhibit cardiac ELFs generation, perhaps due to the negative regulation of PDPN neutralization in Th17 cell proliferation and differentiation. The presence of cardiac ELFs and AHA might offer new opportunities for stratification and early identification of VMC patients.
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Infecções por Coxsackievirus/imunologia , Interleucina-17/imunologia , Glicoproteínas de Membrana/imunologia , Miocardite/imunologia , Estruturas Linfoides Terciárias/imunologia , Células Th17/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Th17/citologiaRESUMO
This study evaluated the release characteristics of mercury from bituminous coal in chemical looping combustion (CLC) using Australian iron ore as the oxygen carrier in a fixed bed reactor. The effects of several parameters, such as temperature in the fuel reactor (FR) and air reactor (AR), gasification medium in the FR, and reaction atmosphere in the AR, on mercury release characteristics, were investigated. The mercury speciation and release amount in the FR and AR under different conditions were further explored. The results indicate that most of the mercury in coal was released in the FR, while the rest of it was released in the AR. Hg0 was found to be the major species in the released mercury. The results also indicate that a higher temperature in the FR led to an increase in the total mercury release amount and a decrease in Hg0 proportion. However, a higher temperature in the AR resulted in a decrease in the total mercury release amount and Hg0 proportion. The increase in the H2O/CO2 ratio of gasification mediums in the FR was beneficial for the increase in the total mercury release amount and Hg0 proportion. A higher O2 concentration in reaction atmosphere in AR had a negligible effect on the total mercury release amount, but a positive effect on Hg0 oxidization.
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Poluentes Atmosféricos/análise , Mercúrio/análise , Atmosfera , Austrália , Carvão Mineral/análise , OxigênioRESUMO
OBJECTIVE: To observe the effect of Bushen Tiaojing Recipe (BTR) and Xiaoyao Pill (XYP) on the morphology and sex hormones secretion of adenohypophysis and ovaries in androgen-induced sterile rats (ASR). METHODS: Fifty 9-day old SD female rats randomly recruited from total 60 rats were subcutaneously injected with testosterone propionate to establish the ASR model. And the rest 10 rats were recruited as the normal group. Thirty successfully modeled rats were recruited and randomly divided into the model group, the BTR group (administered with BTR suspension), and the XYP group (administered with XYP suspension), 10 in each group. Five weeks later, rats were decapitated in the proestrus. Serum levels of estradiol (E2), progesterone (P), testosterone (T), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were detected by radioimmunoassay. The morphologies of adenohypophysis and ovary were observed after HE staining. RESULTS: Compared with the normal group, serum E2 and T levels increased, while FSH and LH levels decreased in the model group (all P < 0.01). The morphology of adenohypophysis and ovary was abnormal in the model group. Compared with the model group, serum E2 and T levels decreased, while FSH and LH levels increased in the BTR group and the XYP group (P < 0.05, P < 0.01). Besides, E2 and T levels in the BTR group and FSH levels in the XYP group restored to normal (all P > 0.05). The damaged structure of adenohypophysis and ovary got restored to different degrees. CONCLUSION: BTR and XYP both could improve ovulation failure.
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Medicamentos de Ervas Chinesas/farmacologia , Ovário/efeitos dos fármacos , Adeno-Hipófise/efeitos dos fármacos , Androgênios/efeitos adversos , Animais , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Infertilidade Feminina/induzido quimicamente , Infertilidade Feminina/tratamento farmacológico , Hormônio Luteinizante/sangue , Ovulação , Progesterona/sangue , Ratos , Ratos Sprague-Dawley , Testosterona/sangueRESUMO
OBJECTIVE: To explore the potential molecular mechanisms for Bushen Tiaojing Recipe (BTR) improving the endocrine function of ovarian granular cells by observing the effect of BTR containing serum on follicle stimulating hormone/cyclic adenosine monophosphate-protein kinase A (FSH/ cAMP-PKA) pathway in in vitro cultured human ovarian granular cells. METHODS: The primary ovarian granular cells collected from in vitro fertilization-embryo transfer patients were cultured for 24 h. The human and rat serum containing different concentrations of BTR (low, medium, high dose), and their normal serums were co-incubated with ovarian granular cells for 48 h respectively, and then they were divided into the low, medium, high dose BTR groups and the control group. The levels of estradiol (E2), progesterone (P), and cyclic adenosine monophosphate (cAMP) in the culture medium were measured by radioimmunoassay. The protein expression of FSHR in ovarian granular cells was detected by Western Blot. The mRNA expression of follicle stimulating hormone receptor (FSHR) and P450 aromatase (P450arom) in ovarian granular cells were detected by Real-time PCR. RESULTS: In human BTR containing serum groups: Compared with control group, the levels of E2 and cAMP in the culture medium were higher (both P < 0.05) in the medium and high dose BTR groups; the levels of P in the culture medium decreased in the medium dose BTR group (P < 0.01). The protein and mRNA expression of FSHR in ovarian granular cells increased (all P < 0.01), the mRNA expressions of P450arom in ovarian granular cells were higher (P < 0.05, P< 0.01) in the medium and high dose BTR groups. In rat BTR containing serum groups: Compared with the control group, the levels of E2 in the culture medium were higher (all P < 0.01), cAMP in the culture medium were higher (P < 0.05, P < 0.01) in the medium and high dose BTR group; the levels of P in the culture medium decreased in the medium dose BTR group (P < 0.01). The protein and mRNA expression of FSHR in ovarian granular cells were higher (all P < 0.01), the mRNA expression of P450arom in ovarian granular cells increased in the medium and high dose BTR groups (P < 0.05, P < 0.01). CONCLUSION: BTR could possibly improve the endocrine function of ovarian granular cells by regulating main effector molecules FSHR, cAMP, P450arom, and E2 in FSH/cAMP-PKA pathway of ovarian granular cells.
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Medicamentos de Ervas Chinesas/farmacologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células Cultivadas , Proteína Quinase Tipo I Dependente de AMP Cíclico/metabolismo , Feminino , Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/citologia , Humanos , Soro/química , Transdução de Sinais/efeitos dos fármacosRESUMO
Biomass-derived carbon quantum dots (CQDs) have the advantage of being green and low-cost, but their complex structure makes the study of their formation mechanism encounter a bottleneck. Lignin-derived CQDs were prepared by a two-step process of "low-temperature liquid depolymerization" coupled with "hydrothermal reaction" in a mild organic acid system. In the first step of the low-temperature acidolysis process, the lignin polymer first undergoes deethering and depolymerization reactions. During the hydrothermal process in the second step, the organic small molecules on the surface of the supernatant are enriched with reactive groups that are dehydrated, condensed, crosslinked, and carbonized under high temperature and pressure to form CQDs. On the other hand, these activated large sp2 carbon domains in the oxidized solid residue from lignin acidolysis undergo hydrothermal cleavage under high-temperature and high-pressure conditions, followed by deoxygenation and eventual decomposition into small carbon domain CQDs products. Among them, the supernatant component C1 after lignin acidolysis with abundant N-H and C-OH reactive groups is targeted as a key precursor for the formation of lignin-derived CQDs, and the resulting CQDs have both the highest QY (19.5%) and yield (16.5%). This study bridges the research gap on the formation mechanism of biomass-derived CQDs and offers a reference for the sustainable preparation of biomass-derived CQDs.
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Carbono , Lignina , Pontos Quânticos , Lignina/química , Pontos Quânticos/química , Carbono/química , Temperatura , Fluorescência , BiomassaRESUMO
BACKGROUND: Ferroptosis, a type of autophagy-dependent cell death, has been implicated in the pathogenesis of lung adenocarcinoma (LUAD). This study aimed to investigate the involvement of coatomer protein complex I subunit zeta 1 (COPZ1) in ferroptosis and ferritinophagy in LUAD. METHODS: Publicly available human LUAD sample data were obtained from the TCGA database to analyze the association of COPZ1 expression with LUAD grade and patient survival. Clinical samples of LUAD and para-carcinoma tissues were collected. COPZ1-deficient LUAD cell model and xenograft model were established. These models were analyzed to evaluate tumor growth, lipid peroxidation levels, mitochondrial structure, autophagy activation, and iron metabolism. RESULTS: High expression of COPZ1 was indicative of malignancy and poor overall survival. Clinical LUAD tissues showed increased COPZ1 expression and decreased nuclear receptor coactivator 4 (NCOA4) expression. COPZ1 knockdown inhibited xenograft tumor growth and induced apoptosis. COPZ1 knockdown elevated the levels of ROS, Fe2+ and lipid peroxidation. COPZ1 knockdown also caused mitochondrial shrinkage. Liproxstatin-1, deferoxamine, and z-VAD-FMK reversed the effects of COPZ1 knockdown on LUAD cell proliferation and ferroptosis. Furthermore, COPZ1 was directly bound to NCOA4. COPZ1 knockdown restricted FTH1 expression and promoted NCOA4 and LC3 expression. NCOA4 knockdown reversed the regulation of iron metabolism, lipid peroxidation, and mitochondrial structure induced by COPZ1 knockdown. COPZ1 knockdown induced the translocation of ferritin to lysosomes for degradation, whereas NCOA4 knockdown disrupted this process. CONCLUSION: This study provides novel evidence that COPZ1 regulates NCOA4-mediated ferritinophagy and ferroptosis. These findings provide new insights into the pathogenesis and potential treatment of LUAD.
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Adenocarcinoma de Pulmão , Proteína Coatomer , Ferritinas , Ferroptose , Neoplasias Pulmonares , Coativadores de Receptor Nuclear , Animais , Feminino , Humanos , Camundongos , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/genética , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Ferritinas/metabolismo , Ferritinas/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Camundongos Nus , Coativadores de Receptor Nuclear/metabolismo , Coativadores de Receptor Nuclear/genética , Proteína Coatomer/genética , Proteína Coatomer/metabolismoRESUMO
The aim of the study was to elucidate the impact of different moisture phases during gas injection on coalbed methane displacement. The coal samples were treated with two methods: water vapor adsorption and liquid water stirring. The differences in the coal samples treated with various moisture phases during gas injection for coalbed methane displacement were investigated by using the isothermal adsorption curves of CH4, N2, and H2O in coal and N2 displacement of CH4 in coal. The results indicate that variations in the gas adsorption capacity of coal are treated with different moisture phases. The gas adsorption capacities and displacement capacities of the coal samples treated with the water vapor adsorption methods are better than those treated with the stirring methods. In the isothermal adsorption experiment, for the coal samples treated with different moisture phases, at a moisture content of 2.75%, the saturated adsorption capacities of CH4/N2 are 0.204/0.189 (cm3/g), and at a moisture content of 5.63%, the saturated adsorption capacities of CH4/N2 are 0.151/0.139 (cm3/g). In addition, in the displacement experiment, for the coal samples treated with different moisture phases, at a moisture content of 2.75%, the difference in the total gas adsorption capacities is 0.62 cm3/g and the difference in the CH4 adsorption capacities is 0.473 cm3/g, and at a moisture content of 5.63%, the difference in the total gas adsorption capacities is 0.3 cm3/g and the difference in CH4 adsorption capacities is 0.22 cm3/g. For the coal samples treated with various moisture phases, the differences in the CH4/N2 adsorption and displacement capacities are greater at a moisture content of 2.75% than at 5.63%. Notably, the moisture phase has only a marginal influence on the CH4 desorption capacity and desorption rate. The study is important to understand the interactions between coal and moisture.
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Studies have shown that Sacubitril/valsartan (Sac/Val) can reduce myocardial inflammation in myocarditis mice, in addition to its the recommended treatment of heart failure. However, the underlying mechanisms of Sac/Val in myocarditis remain unclear. C-type natriuretic peptide (CNP), one of the targeting natriuretic peptides of Sac/Val, was recently reported to exert cardio-protective and anti-inflammatory effects in cardiovascular systems. Here, we focused on circulating levels of CNP in patients with acute myocarditis (AMC) and whether Sac/Val modulates inflammation by targeting CNP in experimental autoimmune myocarditis (EAM) mice as well as LPS-induced RAW 264.7 cells and bone marrow derived macrophages (BMDMs) models. Circulating CNP levels were higher in AMC patients compared to healthy controls, and these levels positively correlated with the elevated inflammatory cytokines IL-6 and monocyte count. In EAM mice, Sac/Val alleviated myocardial inflammation while augmenting circulating CNP levels rather than BNP and ANP, accompanied by reduction in intracardial M1 macrophage infiltration and expression of inflammatory cytokines IL-1ß, TNF-α, and IL-6. Furthermore, Sac/Val inhibited CNP degradation and directly blunted M1 macrophage polarization in LPS-induced RAW 264.7 cells and BMDMs. Mechanistically, the effects might be mediated by the NPR-C/cAMP/JNK/c-Jun signaling pathway apart from NPR-B/cGMP/NF-κB pathway. In conclusion, Sac/Val exerts a protective effect in myocarditis by increasing CNP concentration and inhibiting M1 macrophages polarization.
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Aminobutiratos , Compostos de Bifenilo , Combinação de Medicamentos , Macrófagos , Miocardite , Peptídeo Natriurético Tipo C , Valsartana , Animais , Camundongos , Miocardite/tratamento farmacológico , Miocardite/metabolismo , Miocardite/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Aminobutiratos/farmacologia , Valsartana/farmacologia , Células RAW 264.7 , Masculino , Humanos , Compostos de Bifenilo/farmacologia , Peptídeo Natriurético Tipo C/farmacologia , Tetrazóis/farmacologia , Doença Aguda , Modelos Animais de Doenças , Feminino , Citocinas/metabolismo , Citocinas/sangue , Camundongos Endogâmicos C57BL , Anti-Inflamatórios/farmacologia , Polaridade Celular/efeitos dos fármacosRESUMO
Tumor cells possess complex immune evasion mechanisms to evade immune system attacks, primarily through metabolic reprogramming, which significantly alters the tumor microenvironment (TME) to modulate immune cell functions. When a tumor is sufficiently immunogenic, it can activate cytotoxic T-cells to target and destroy it. However, tumors adapt by manipulating their metabolic pathways, particularly glucose, amino acid, and lipid metabolism, to create an immunosuppressive TME that promotes immune escape. These metabolic alterations impact the function and differentiation of non-tumor cells within the TME, such as inhibiting effector T-cell activity while expanding regulatory T-cells and myeloid-derived suppressor cells. Additionally, these changes lead to an imbalance in cytokine and chemokine secretion, further enhancing the immunosuppressive landscape. Emerging research is increasingly focusing on the regulatory roles of non-tumor cells within the TME, evaluating how their reprogrammed glucose, amino acid, and lipid metabolism influence their functional changes and ultimately aid in tumor immune evasion. Despite our incomplete understanding of the intricate metabolic interactions between tumor and non-tumor cells, the connection between these elements presents significant challenges for cancer immunotherapy. This review highlights the impact of altered glucose, amino acid, and lipid metabolism in the TME on the metabolism and function of non-tumor cells, providing new insights that could facilitate the development of novel cancer immunotherapies.
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Pyroptosis is a type of programmed cell death characterized by cell swelling and osmotic lysis, resulting in cytomembrane rupture and release of immunostimulatory components, which play a role in several pathological processes. Significant cellular responses to various stimuli involve the formation of inflammasomes, maturation of inflammatory caspases, and caspase-mediated cleavage of gasdermin. The function of pyroptosis in disease is complex but not a simple angelic or demonic role. While inflammatory diseases such as sepsis are associated with uncontrollable pyroptosis, the potent immune response induced by pyroptosis can be exploited as a therapeutic target for anti-tumor therapy. Thus, a comprehensive review of the role of pyroptosis in disease is crucial for further research and clinical translation from bench to bedside. In this review, we summarize the recent advancements in understanding the role of pyroptosis in disease, covering the related development history, molecular mechanisms including canonical, non-canonical, caspase 3/8, and granzyme-mediated pathways, and its regulatory function in health and multiple diseases. Moreover, this review also provides updates on promising therapeutic strategies by applying novel small molecule inhibitors and traditional medicines to regulate pyroptosis. The present dilemmas and future directions in the landscape of pyroptosis are also discussed from a clinical perspective, providing clues for scientists to develop novel drugs targeting pyroptosis.
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Piroptose , Piroptose/genética , Humanos , Inflamassomos/metabolismo , Inflamassomos/genética , Inflamassomos/imunologia , Granzimas/genética , Granzimas/metabolismo , Sepse/genética , Sepse/patologia , Sepse/metabolismo , Sepse/imunologia , Caspase 8/genética , Caspase 8/metabolismo , Neoplasias/genética , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Transdução de SinaisRESUMO
Cisplatin (DDP)-based chemoradiotherapy is one of the standard treatments for nasopharyngeal carcinoma (NPC). However, the sensitivity and side effects of DDP to patients remain major obstacles for NPC treatment. This research aimed to study DDP sensitivity regulated by cancer-associated fibroblasts (CAFs) through modulating ferroptosis. We demonstrated that DDP triggered ferroptosis in NPC cells, and it inhibited tumor growth via inducing ferroptosis in xenograft model. CAFs secreted high level of FGF5, thus inhibiting DDP-induced ferroptosis in NPC cells. Mechanistically, FGF5 secreted by CAFs directly bound to FGFR2 in NPC cells, leading to the activation of Keap1/Nrf2/HO-1 signaling. Rescued experiments indicated that FGFR2 overexpression inhibited DDP-induced ferroptosis, and CAFs protected against DDP-induced ferroptosis via FGF5/FGFR2 axis in NPC cells. In vivo data further showed the protective effects of FGF5 on DDP-triggered ferroptosis in NPC xenograft model. In conclusion, CAFs inhibited ferroptosis to decrease DDP sensitivity in NPC through secreting FGF5 and activating downstream FGFR2/Nrf2 signaling. The therapeutic strategy targeting FGF5/FGFR2 axis from CAFs might augment DDP sensitivity, thus decreasing the side effects of DDP in NPC treatment.
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Fibroblastos Associados a Câncer , Ferroptose , Neoplasias Nasofaríngeas , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Linhagem Celular Tumoral , Neoplasias Nasofaríngeas/patologia , Resistencia a Medicamentos Antineoplásicos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Fator 5 de Crescimento de FibroblastosRESUMO
REBa 2 Cu 3 O 7 - x (REBCO, RE = rare earth)-coated conductor is a competitive option in terms of current-carrying capacity and high-stress durability in developing high-field magnets for nuclear magnetic resonance (NMR) research. Meanwhile, a technical challenge in utilizing a stand-alone REBCO NMR magnet is an unexpected difference in the field uniformity between the designed and measured values after being constructed and charged, i.e., harmonic errors. Bortot et al., and Li et al., reported analytic evidence of the related issue. However, sufficient research has not yet been conducted, so evidence should be supplemented further. Here we report harmonic errors due to screening current and inconsistent conductor thickness, confirmed by a 400 MHz 1H NMR magnet development project. The magnet was first charged up to its operating current, and then multiple overcharge-discharge cycles were applied, which was an empirically optimized operation protocol. A field mapping device obtained magnetic fields at designated locations in the room-temperature bore. The result showed over 100 ppm field uniformity difference between designed and measured values. A simulation model was developed considering screening current and inconsistent conductor thickness for reproducing the field distribution. Comparison of voltages and fields between simulation and measurement validated the model. Further analysis of the overcharge-discharge effect on harmonic errors demonstrated that even and odd-order harmonics are mainly attributed to screening current and geometric inconsistency while confirming the limitation of the screening current mitigation effect. Hence, we concluded that the desirable requirement of the sub-ppm level field uniformity generation might be barely possible with the current REBCO NMR magnet design approach.
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This study developed a novel selenium-doped metal nitride carbon, Fe-NC-Se, via pyrolysis and impregnated hydrothermal methods for elemental mercury removal from coal-fired flue gas. The Fe-NC-Se demonstrated a remarkable mercury removal performance, achieving an average efficiency of 96.98% within 60 min at an optimal Se/Fe ratio of 2:1 and temperature of 110 °C, which was 2.5 times higher than that of the pristine Fe-NC (iron nitride carbon). Notably, Fe-NC-Se maintained an 84% efficiency in a high SO2 environment (1600 ppm), indicating strong resistance to SO2 poisoning. Long-term testing over 24 h showed a consistent removal efficiency of 84.75%, suggesting potential for recyclability. Advanced characterization techniques, including TEM (transmission electron microscopy) and XPS (X-ray photoelectron spectrometer), along with Density Functional Theory calculations, were employed to explore the removal mechanism. Results indicated that selenium doping enhanced surface charge transfer and the reactivity of surface atoms, facilitating mercury oxidation and sequestration. The oxidized Hg2+ was anchored by Se and partially stabilized by C, N, and Fe atoms, enhancing the catalyst's effectiveness. This work not only advances the design of mercury abatement catalysts but also supports the industrial applicability of Fe-NC-Se in flue gas treatment.
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The remediation of heavy metal deserves to be on the agenda, with the adsorbent design bearing the brunt of it. In this study, the molecule (4, 6-diamino-2-mercaptopyrimidine, DMP) containing thiol (-SH) and amino (-NH2) functional groups was grafted onto Uio-66-NH2, and a composite metal-organic framework nanomaterial (Zr(NH2)-DMP) was synthesized via a facile post-modification scheme. The morphological characteristics and structural features of the modified adsorbent were characterized by XRD, FT-IR, FE-SEM, EDS, BET, and XPS. The characterization results verified that the post-modification scheme was successfully achieved. The adsorption experiments were carried out to investigate the removal performance of the Zr(NH2)-DMP towards Hg2+ under different influencing parameters. The maximum adsorption capacity of 389.4 mg/g was obtained, and the adsorption equilibrium was achieved within 30 min at pH 6 at room temperature. Adsorption thermodynamic study indicated that the adsorption process was exothermic and spontaneous. The Zr(NH2)-DMP exhibited excellent selectivity for Hg2+, and also has the potential to remove Cu2+, Fe2+, and Zn2+ ions. The introduction of Cl- inhibited the removal of Hg2+ due to the formation of mercuric chlorides (removal efficiency reduced from 97.8 to 95.6%). The removal efficiency of up to 86.7% was obtained after four cycles. The Langmuir isotherm and Pseudo-second kinetic were more suitable for fitting the adsorption process of Hg2+ by Zr(NH2)-DMP. The main removal mechanism could be attributed to the chelation between Hg2+ (soft acid) and nitrogen/sulfur (soft base) elements. These findings convinced that the successful synthesis of Zr(NH2)-DMP provides an option for Hg2+ removal from wastewater.
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Mercúrio , Poluentes Químicos da Água , Águas Residuárias , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Mercúrio/análise , Enxofre , Poluentes Químicos da Água/análise , CinéticaRESUMO
After the coal seam is injected with water, the moisture content in the coal body increases, which affects the output capacity of coalbed methane (CBM). In order to improve the effect of CBM mining, the classical anthracite molecular model has been selected. To analyze the influence of different placement orders of water and methane on the characteristics of coal-adsorbing methane from the micro point of view, a molecular simulation method is used for comprehensive consideration in the study. The results show that H2O does not change the mechanism of CH4 adsorption by anthracite, but it inhibits the adsorption of methane by anthracite. When water enters the system afterward, there arises an equilibrium pressure point where water plays the most significant role in inhibiting methane adsorption by anthracite coals, which increases with increasing moisture content. When water enters the system first, no equilibrium pressure point occurs. The excess adsorption of methane by anthracite when water enters second is higher. The reason is that H2O can replace CH4 at the higher energy adsorption sites of the anthracite structure, while CH4 can only be adsorbed at the lower energy sites, and some of CH4 is not adsorbed. For the coal samples with a low-moisture content system, the equivalent heat of adsorption of CH4 increases first rapidly and then slowly with the increase of pressure. However, it decreases with pressure in the high-moisture content system. The variation of the equivalent heat of adsorption further explains the variation of the magnitude of methane adsorption under different conditions.
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BACKGROUND: Nasopharyngeal carcinoma (NPC) is a head and neck malignant tumor with a high incidence and recurrence rate. The crosstalk between ferroptosis and tumor-associated macrophages (TAMs) is thought to have major implications in interfering with cancers. We intended to explore the effect of acyl-CoA synthetase long-chain family member 4 (ACSL4) on the pathogenesis of NPC via ferroptosis and TAMs. METHODS: Differential genes in NPC patients were analyzed using publicly available databases, and the ferroptosis-related gene ACSL4 was identified. Expression of ACSL4 in NPC cell lines and xenografted mice was examined. Colony formation, cell proliferation, migration, and invasion were assessed. The abundance of epithelial-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin, and Vimentin) was confirmed. Lipid peroxidation levels and related markers were measured. Clophosome was administered to determine the role of TAMs in NPC mice. RESULTS: Low levels of ACSL4 were observed in NPC patients and CNE-2 and 5-8F cells. Erastin (a ferroptosis inducer) and ACSL4 increased lipid peroxidation, decreased cell viability, colony formation, cell proliferation, migration and invasion, and inhibited EMT. Moreover, Erastin and ACSL4 promoted M2 to M1 macrophage polarization. The effects of erastin and ACSL4 were additive. Ferrostatin-1, an inhibitor of ferroptosis, exerted the opposite effect and reversed the beneficial effects of ACSL4 overexpression. In xenograft mice, ACSL4 and clophosome hindered the growth of NPC, and extra clophosome slightly enhanced the antitumor effect of ACSL4. CONCLUSION: Our findings indicated that ACSL4 inhibited the pathogenesis of NPC, at least through crosstalk between ferroptosis and macrophages, providing potential direction for NPC therapy.
Assuntos
Ferroptose , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Animais , Humanos , Camundongos , Carcinogênese , Linhagem Celular Tumoral , Macrófagos/patologia , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genéticaRESUMO
Developing an environmentally friendly selective catalytic reduction (SCR) catalyst to effectively eliminate both nitric oxides (NO) and toluene has garnered significant attention for regulating emissions from automobiles and the combustion of fossil fuels. This study synthesized a series of novel commercial V2O5-WO3/TiO2 catalysts modified with Cu through the wet impregnation method, which was employed to simultaneously remove NO and toluene from the fuel gas. The assessment of catalyst removal performance was conducted at a selective catalytic reduction system, and the experimental results showed a significant increase in the catalytic activity due to the modification of the copper metal. The 10% Cu/SCR catalyst showed a superior activity that the NO and toluene conversion reached 100% and 95.56% at 300 °C, respectively. Subsequently, various characterization techniques were employed to investigate the crystal phase, morphology, physical features, chemical states, and surface acidity properties of the synthesis catalysts. According to the characterization results, the presence of Cu metal did not have a noticeable impact on the physical property. However, the redox performance was enhanced, and the number of surface acidic sites was also increased after adding Cu to the SCR catalyst. Furthermore, the redox cycle of Cu metal and V species was facilitated to produce more active oxygen which helped to improve the NO and toluene conversion. This work offered a novel perspective into the synergistic oxidation of both NO and toluene, which was potentially relevant for improving the selective catalytic reduction process in coal-fired power plants.