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The synthesis of multicarbon (C2+) products remains a substantial challenge in sustainable CO2 electroreduction owing to the need for sufficient current density and faradaic efficiency alongside carbon efficiency. Herein, we demonstrate ampere-level high-efficiency CO2 electroreduction to C2+ products in both neutral and strongly acidic (pH = 1) electrolytes using a hierarchical Cu hollow-fiber penetration electrode (HPE). High concentration of K+ could concurrently suppress hydrogen evolution reaction and facilitate C-C coupling, thereby promoting C2+ production in strong acid. By optimizing the K+ and H+ concentration and CO2 flow rate, a faradaic efficiency of 84.5% and a partial current density as high as 3.1 A cm-2 for C2+ products, alongside a single-pass carbon efficiency of 81.5% and stable electrolysis for 240 h were demonstrated in a strong acidic solution of H2SO4 and KCl (pH = 1). Experimental measurements and density functional theory simulations suggested that tensile-strained Cu HPE enhances the asymmetric C-C coupling to steer the selectivity and activity of C2+ products.
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The electrochemical propylene epoxidation reaction (PER) provides a promising route for ecofriendly propylene oxide (PO) production, instantly generating active halogen/oxygen species to alleviate chloride contamination inherent in traditional PER. However, the complex processes and unsatisfactory PO yield for current electrochemical PER falls short of meeting industrial application requirements. Herein, a spatial-coupling strategy over RuO2/Ti hollow-fiber penetration electrode (HPE) is adopted to facilitate efficient PO production, significantly improving PER performance to the ampere level (achieving over 80% PO faradaic efficiency and a maximum PO current density of 859 mA cm-2). The synergetic combination of the penetration effect of HPE and the spatial-coupled reaction sequence, enables the realization of ampere-level PO production with high specificity, exhibiting significant potentials for economically viable PER applications.
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Electroreduction of CO2 to CO is a promising route for greenhouse gas resource utilization, but it still suffers from impractical current density and poor durability. Here, a nanosheet shell (NS) vertically standing on the Ag hollow fiber (NS@Ag HF) surface formed by electrochemical surface reconstruction is reported. As-prepared NS@Ag HF as a gas penetration electrode exhibited a high CO faradaic efficiency of 97% at an ultra-high current density of 2.0 A cm-2 with a sustained performance for continuous >200 h operation. The experimental and theoretical studies reveal that promoted surface electronic structures of NS@Ag HF by the nanosheets not only suppress the competitive hydrogen evolution reaction but also facilitate the CO2 reduction kinetics. This work provides a feasible strategy for fabricating robust catalysts for highly efficient and stable CO2 reduction.
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Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO2 ), i.e., artificial photosynthesis (AP) is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C2 compounds with a high CO2 conversion rate remains challenging for current AP technologies. We performed CO2 photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C2 H5 OH) selectivity of>99 % and a CO2 conversion rate of up to 17.1â mmol gcat -1 h-1 with sustained performance. Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few-layer graphene overlayer, which also favored an efficient CO2 to C2 H5 OH conversion pathway.
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OBJECTIVE: To investigate the clinicopathological features, diagnosis, differential diagnosis, treatment and prognosis of myxoid liposarcoma (MLPS)of the testis. METHODS: We observed the clinicopathological and immunophenotypic characteristics of primary MLPS of the testis in a male patient and reviewed the relevant literature. RESULTS: The tumor was located in the right testicular parenchyma, of multi-nodular growth microscopically. The tumor cells were stellate, fusiform, foamy and signet ring-like, with abundant mucus and a network of fine branched or plexiform capillaries in the stroma. Immune phenotype-related findings included positive p16 and H3K27ME3 tumor cells and CD34 vascular network, negative CD99, CK, Desmin, FLI agreed-1, S-100, SMA, STAT6, TFE3, α-inhibin and SOX1, and a Ki-67 proliferation index of about 15%. CONCLUSION: Primary MLPS of the testis is rare, which needs to be differentiated from myxosarcoma, rhabdomyosarcoma, myxoma, spindle cell or pleomorphic liposarcoma, and lipophiloma. Immunohistochemical markers Vimentin, s-100 and CD34 can assist in the diagnosis of the tumor.
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Lipossarcoma Mixoide , Masculino , Humanos , Lipossarcoma Mixoide/patologia , Testículo/patologia , Imuno-Histoquímica , Antígenos CD34 , Diagnóstico DiferencialRESUMO
Electrochemical conversion of CO2 into valuable feedstocks is a promising strategy for carbon neutrality. However, it remains a challenge to possess a large current density, a high faradaic efficiency and excellent stability for practical applications of CO2 utilization. Herein, we report a facile tactic that enables exceedingly efficient CO2 electroreduction to CO by virtue of low-coordination chloride ion (Cl- ) adsorption on a silver hollow fiber (Ag HF) electrode. A CO faradaic efficiency of 92.3 % at a current density of one ampere per square centimeter (1â A cm-2 ) in 3.0â M KCl with a sustained performance observed during a 150-hour test was achieved, which is better than state-of-the-art electrocatalysts. The electrochemical results and density functional theory (DFT) calculations suggested a low-coordination Cl- adsorption on surface of Ag HF, which not only suppressed the competitive hydrogen evolution reaction (HER), but also facilitated the CO2 reduction kinetics.
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Attachment and separation of sulfate-reducing bacteria (SRB) biofilm on stainless steel (SS) in simulated cooling water with and without different sterilization treatments was investigated by calculation of surface energy, theoretical work of adhesion and analysis of Scanning Electron Microscope/Energy Dispersive Spectrometer. Two types of biocides, glutaraldehyde and Polyhexamethylene guanidine (PHMG), and electromagnetic treatment were used in this paper. The results show that PHMG had the best bactericidal performance, followed by glutaraldehyde, and electromagnetic treatment was the lowest one. The theoretical work of adhesion was used to quantitatively evaluate the adhesion of biofilm on the surface of the metal. Theoretical work of adhesion between biofilm and SS in simulated cooling water increased with time. The theoretical adhesion work and adhesive capacity of biofilm to SS surface increased after treating with glutaraldehyde while decreasing after treating with PHMG and electromagnetic field. As the theoretical adhesion work decreased, the biofilm was gradually removed from the stainless steel surface. On the contrary, the biofilm adhered more firmly. The results of SEM were also consistent with the calculation results of theoretical adhesion work. The results obtained indicated that electromagnetic treatment had the lowest effect in sterilization but the best in biofilm separation.
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Desinfetantes , Aço Inoxidável , Aderência Bacteriana , Biofilmes , Desinfecção , Propriedades de SuperfícieRESUMO
Electroreduction of CO2 to multi-carbon products has attracted considerable attention as it provides an avenue to high-density renewable energy storage. However, the selectivity and stability under high current densities are rarely reported. Herein, B-doped Cu (B-Cu) and B-Cu-Zn gas diffusion electrodes (GDE) were developed for highly selective and stable CO2 conversion to C2+ â products at industrially relevant current densities. The B-Cu GDE exhibited a high Faradaic efficiency of 79 % for C2+ â products formation at a current density of -200â mA cm-2 and a potential of -0.45â V vs. RHE. The long-term stability for C2+ formation was substantially improved by incorporating an optimal amount of Zn. Operando Raman spectra confirm the retained Cu+ species under CO2 reduction conditions and the lower overpotential for *OCO formation upon incorporation of Zn, which lead to the excellent conversion of CO2 to C2+ products on B-Cu-Zn GDEs.
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Developing highly efficient and selective electrocatalysts for the CO2 reduction reaction to produce value-added chemicals has been intensively pursued. We report a series of Cux Oy Cz nanostructured electrocatalysts derived from a Cu-based MOF as porous self-sacrificial template. Blending catalysts with polytetrafluoroethylene (PTFE) on gas diffusion electrodes (GDEs) suppressed the competitive hydrogen evolution reaction. 25 to 50â wt % teflonized GDEs exhibited a Faradaic efficiency of ≈54 % for C2+ products at -80â mA cm-2 . The local OH- ions activity of PTFE-modified GDEs was assessed by means of closely positioning a Pt-nanoelectrode. A substantial increase in the OH- /H2 O activity ratio due to the locally generated OH- ions at increasing current densities was determined irrespective of the PTFE amount.
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Although the targeted tyrosine kinase inhibitor imatinib mesylate (IM) has achieved significant responses against CML in the clinical setting, a small proportion of patients fail to respond to IM treatment and their disease continues to progress, indicating resistance to IM therapy. As a secreted extracellular matrix protein, cysteine-rich protein 61 (Cyr61) plays an important role in the resistance of solid tumors to chemotherapy, but its role in CML is unclear. In the present study, we observed that Cyr61 levels were upregulated in the plasma and bone marrow (BM) of patients with CML as well as in K562 cells. This upregulation of Cyr61 significantly decreased IM-induced cellular apoptosis of K562 cells through nuclear factor kappa B/B-cell lymphoma 2 pathways. Inhibition of Cyr61 restored the chemosensitivity of K562 cells to IM both in vitro and in vivo. Thus, our results showed for the first time that Cyr61 plays an important role in regulating the chemosensitivity of CML cells to IM, suggesting that selectively targeting Cyr61 directly or its relevant effector pathways may provide potential value in improving the clinical response of patients with CML to IM treatment.
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Proteína Rica em Cisteína 61/metabolismo , Mesilato de Imatinib/farmacologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Inibidores de Proteínas Quinases/farmacologia , Regulação para Cima/efeitos dos fármacosRESUMO
The miR-17-92 cluster has been involved in the cell cycle, apoptosis, and signaling. However, its transcriptional regulation has not been fully characterized. To elucidate the transcriptional regulation, the promoter of miR-17-92 was analyzed in detail in pig here. We found that, as an intronic miRNA, porcine miR-17-92 cluster was regulated by two independent promoters, an A/T-rich region directly upstream of the miR-17-92 coding sequence, and a G/C-rich region corresponding to the host gene promoter of the human miR-17-92 cluster. Several cis-regulatory elements were identified including sites for c-Myc, NFY, E2F3, and SP1, among which NFY and c-Myc sites were present in both A/T- and G/C-rich regions, while E2F3 and SP1 sites only existed in G/C-rich region. Sites for c-Myc, E2F3, and SP1 were positive for regulating transcription. NFY sites played bipartite roles, functioning as a repressor for the A/T-rich region, and as an activator for the G/C-rich region. Additionally, we found that levels of individual miRNAs in the cluster were not promoted completely in parallel with each other or with pri-miR-17-92 by the A/T-rich region, through using a self-made vector by modifying pGL3-basic in which firefly luciferase gene was replaced with an miR-17-92 cluster and a direct upstream A/T-rich region. The expression regulation of miR-17-92 is complicated and the results will contribute to further revealing the regulatory mechanisms under the expression of the miR-17-92 cluster.
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MicroRNAs/genética , Elementos Reguladores de Transcrição , Animais , Composição de Bases , Linhagem Celular , Regulação da Expressão Gênica , Família Multigênica , Regiões Promotoras Genéticas , SuínosRESUMO
The maturation of natural killer (NK) cells is critical for the acquisition of robust effector functions and the immune response to tumors. However, the influence of psychological stress on NK-cell maturation remains unknown. In this study, we investigated the alteration of NK-cell maturation in response to enriched environment (EE) exposure, which induced eustress, or positive stress, in mice. Analysis of markers representing distinct mature stages revealed that EE promoted the terminal maturation of NK cells both centrally in the bone marrow and peripherally in the spleen and blood. Additionally, EE increased CD27+ immature and intermediate-mature NK cell proliferation in the bone marrow. Furthermore, EE exposure brought about a similar promoting effect on NK-cell maturation in tumor-bearing mice. In tumor-bearing mice, EE substantially enhanced the proliferative potential of splenic CD27+ NK cells compared to those in the bone marrow. EE-housed mice displayed a tumor-resistant phenotype and an increased proportion of intratumoral NK cells, especially CD11b+ CD27- mature NK cells, while splenectomy abolished the tumor-retardant effect caused by EE and EE-induced NK-cell infiltration into tumors. Given that our previous study demonstrated an important role for NK cells in EE-induced tumor inhibition, the findings of this study further indicate that the enhanced maturation and proliferation of splenic NK cells may contribute to EE-induced tumor inhibition to some extent. Taken together, the results of this study suggest a positive modulating effect of environment-induced eustress on NK-cell maturation, with potential implications for understanding how eustress boosts NK-cell antitumor immunity.
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Meio Ambiente , Células Matadoras Naturais/imunologia , Estresse Psicológico/imunologia , Animais , Medula Óssea , Células da Medula Óssea/imunologia , Diferenciação Celular/imunologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Citotoxicidade Imunológica/imunologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/fisiologia , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Baço/imunologiaRESUMO
IFN-induced protein with tetratricopeptide repeats 2 (IFIT2) plays important roles in host defense against viral infection as revealed by studies in humans and mice. However, little is known on porcine IFIT2 (pIFIT2). Here, we performed molecular cloning, expression profile, and transcriptional regulation analysis of pIFIT2. pIFIT2 gene, located on chromosome 14, is composed of two exons and have a complete coding sequence of 1407 bp. The encoded polypeptide, 468 aa in length, has three tetratricopeptide repeat motifs. pIFIT2 gene was unevenly distributed in all eleven tissues studied with the most abundance in spleen. Poly(I:C) treatment notably strongly upregulated the mRNA level and promoter activity of pIFIT2 gene. Upstream sequence of 1759 bp from the start codon which was assigned +1 here has promoter activity, and deltaEF1 acts as transcription repressor through binding to sequences at position - 1774 to - 1764. Minimal promoter region exists within nucleotide position - 162 and - 126. Two adjacent interferon-stimulated response elements (ISREs) and two nuclear factor (NF)-κB binding sites were identified within position - 310 and - 126. The ISRE elements act alone and in synergy with the one closer to start codon having more strength, so do the NF-κB binding sites. Synergistic effect was also found between the ISRE and NF-κB binding sites. Additionally, a third ISRE element was identified within position - 1661 to - 1579. These findings will contribute to clarifying the antiviral effect and underlying mechanisms of pIFIT2.
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Proteínas/genética , Suínos/genética , Ativação Transcricional , Animais , Proteínas Reguladoras de Apoptose , Sequência de Bases , Clonagem Molecular/métodos , Éxons , Humanos , Camundongos , Filogenia , Regiões Promotoras Genéticas , Biossíntese de Proteínas , Proteínas/metabolismo , Proteínas de Ligação a RNA , Elementos de Resposta , Fatores de Transcrição/genética , TranscriptomaRESUMO
Interferon-induced protein with tetratricopeptide repeats (IFIT) 2 is associated with various viral infections and pathogenesis in humans and mice. However, there are few reports on IFIT2 in pigs and the polymorphic information remains unclear. Here, by using a direct PCR sequencing method, we identified four single nucleotide polymorphisms (SNPs), c.259G>A (p.Gly87Ser), c.520T>G (p.Phe174Val), c.571C>T (p.Pro191Ser), and c.879A>G (p.Glu293Glu), for the first time in the coding sequence of the porcine (p) IFIT2 gene from a Chinese local breed (Hebao pig), Western commercial pig breeds (Yorkshire and Landrace), and a Chinese developed breed (Beijing Black pig). SNP c.520T>G (p.Phe174Val) leads to the addition of a tetratricopeptide repeat motif, characteristic structure of the IFIT family. SNPs c.259G>A and c.520T>G are medium polymorphic loci (0.25 < polymorphic information content < 0.5) and distributed differently in Western pig breeds and the Chinese local pig, Hebao, which is well known for its strong resistance to disease. Additionally, they are completely linked. The four SNPs constituted five haplotypes with GTCA and AGCA as dominant. The haplotype variant AGCA, which is mainly present in Hebao pigs, significantly synergized the poly(I:C)-induced activation of transcription factors, including NF-κB and IFN-stimulated response element (ISRE)-binding factors, and the expression of interferon ß, indicating that the variant contributes to the induction or magnitude of the immune response upon viral infection. The data showed that variant AGCA might be useful in improving the resistance of pigs to viruses through marker-assisted selection.
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Proteínas de Transporte/genética , Sus scrofa/genética , Animais , Proteínas Reguladoras de Apoptose , Cruzamento , China , Haplótipos/genética , NF-kappa B/genética , Fases de Leitura Aberta , Filogenia , Poli I-C/genética , Polimorfismo de Nucleotídeo Único/genética , Ligação Proteica , Proteínas/genética , Proteínas de Ligação a RNA , Elementos de Resposta , Suínos/genéticaRESUMO
BACKGROUND: Human papillomavirus (HPV) infection is the main etiological factor for the development of cervical cancer. Here we assessed the prevalence and distribution of HPV genotypes in Fujian population. METHODS: A total of 8678 women aging from 17 to 84 years olds were recruited from the Fujian Medical University Union Hospital in Fujian Province. Every woman had a face-to-face interview. Cervical samples were collected from each participant and HPV screening was conducted using microarray hybridization. RESULTS: Our study showed that the HPV prevalence in Fujian province was 38.3%. Among the positive individuals, 70.6% were detected for single HPV infection, 29.4% for multiple HPV infections. Further analysis showed that the prevalence of HPV infection significantly increased from 2009 to 2015. The four most common high risk human papillomavirus (HR-HPV) genotypes were HPV16 (8.5%), HPV52 (7.9%), HPV58 (6.2%), HPV 53 (3.5%), collectively accounting for 60.5% of all detected HPV infection. Age subgroup analysis showed two peaks for the frequencies of overall and multiple HPV infections, one for the group of women under 25 years old, and the other for the group over 55 years old. CONCLUSIONS: HPV infection is becoming serious in Fujian province, which indicates the imperative to implement a HPV vaccination and screening program for this region.
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Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Prevalência , Adulto JovemRESUMO
Electrochemical capacitors (i.e. supercapacitors) include electrochemical double-layer capacitors that depend on the charge storage of ion adsorption and pseudo-capacitors that are based on charge storage involving fast surface redox reactions. The energy storage capacities of supercapacitors are several orders of magnitude higher than those of conventional dielectric capacitors, but are much lower than those of secondary batteries. They typically have high power density, long cyclic stability and high safety, and thus can be considered as an alternative or complement to rechargeable batteries in applications that require high power delivery or fast energy harvesting. This article reviews the latest progress in supercapacitors in charge storage mechanisms, electrode materials, electrolyte materials, systems, characterization methods, and applications. In particular, the newly developed charge storage mechanism for intercalative pseudocapacitive behaviour, which bridges the gap between battery behaviour and conventional pseudocapacitive behaviour, is also clarified for comparison. Finally, the prospects and challenges associated with supercapacitors in practical applications are also discussed.
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CO2 electroreduction is a promising technique for satisfying both renewable energy storage and a negative carbon cycle. However, it remains a challenge to convert CO2 into C2 products with high efficiency and selectivity. Herein, we report a nitrogen-doped ordered cylindrical mesoporous carbon as a robust metal-free catalyst for CO2 electroreduction, enabling the efficient production of ethanol with nearly 100 % selectivity and high faradaic efficiency of 77 % at -0.56â V versus the reversible hydrogen electrode. Experiments and density functional theory calculations demonstrate that the synergetic effect of the nitrogen heteroatoms and the cylindrical channel configurations facilitate the dimerization of key CO* intermediates and the subsequent proton-electron transfers, resulting in superior electrocatalytic performance for synthesizing ethanol from CO2 .
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Conversion of carbon dioxide (CO2 ) into fuels and chemicals by electroreduction has attracted significant interest, although it suffers from a large overpotential and low selectivity. A Pd-Sn alloy electrocatalyst was developed for the exclusive conversion of CO2 into formic acid in an aqueous solution. This catalyst showed a nearly perfect faradaic efficiency toward formic acid formation at the very low overpotential of -0.26â V, where both CO formation and hydrogen evolution were completely suppressed. Density functional theory (DFT) calculations suggested that the formation of the key reaction intermediate HCOO* as well as the product formic acid was the most favorable over the Pd-Sn alloy catalyst surface with an atomic composition of PdSnO2 , consistent with experiments.
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A series of carbon dots/NiCo2 O4 composites with various morphologies are prepared and tested for supercapacitors. These samples have good electrical conductivities and efficient ions transport paths, so they exhibit high specific capacitances, superior rate performances, and high cycling stabilities. The optimal composite for hybrid supercapacitor exhibits a high energy density up to 62.0 Wh kg-1 .
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IL-1ß plays a major role in the development of rheumatoid arthritis (RA). We previously showed that Cyr61 participates in RA pathogenesis as a proinflammatory factor. Here, we found that the levels of IL-1ß and Cyr61 were higher in RA SF than in osteoarthritis (OA) SF. IL-1ß mRNA and proIL-1ß protein levels were remarkably increased in Cyr61-stimulated FLS; however, IL-1ß was hardly detectable in the supernatant. We also found that the level of adenosine triphosphate (ATP) in SF and ST was significantly increased in RA patients and that the level of IL-1ß in supernatants from Cyr61-activated FLS increased significantly when we added exogenous ATP to the culture. Mechanistically, Cyr61 induced proIL-1ß production in FLS via the AKT-dependent NF-κB signaling pathway, and ATP caused Cyr61-induced proIL-1ß to generate IL-1ß in a caspase-1-dependent manner. Our results reveal a novel role of Cyr61 in RA that involves the promotion of proIL-1ß production in FLS.