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1.
BMC Cancer ; 24(1): 353, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504158

RESUMO

NUP155 is reported to be correlated with tumor development. However, the role of NUP155 in tumor physiology and the tumor immune microenvironment (TIME) has not been previously examined. This study comprehensively investigated the expression, immunological function, and prognostic significance of NUP155 in different cancer types. Bioinformatics analysis revealed that NUP155 was upregulated in 26 types of cancer. Additionally, NUP155 upregulation was strongly correlated with advanced pathological or clinical stages and poor prognosis in several cancers. Furthermore, NUP155 was significantly and positively correlated with DNA methylation, tumor mutational burden, microsatellite instability, and stemness score in most cancers. Additionally, NUP155 was also found to be involved in TIME and closely associated with tumor infiltrating immune cells and immunoregulation-related genes. Functional enrichment analysis revealed a strong correlation between NUP155 and immunomodulatory pathways, especially antigen processing and presentation. The role of NUP155 in breast cancer has not been examined. This study, for the first time, demonstrated that NUP155 was upregulated in breast invasive carcinoma (BRCA) cells and revealed its oncogenic role in BRCA using molecular biology experiments. Thus, our study highlights the potential value of NUP155 as a biomarker in the assessment of prognostic prediction, tumor microenvironment and immunotherapeutic response in pan-cancer.


Assuntos
Neoplasias da Mama , Carcinoma , Humanos , Feminino , Neoplasias da Mama/genética , Apoptose , Mama , Proliferação de Células/genética , Prognóstico , Microambiente Tumoral/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética
2.
Physiol Plant ; 176(3): e14378, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887925

RESUMO

D-2-hydroxyglutarate dehydrogenase (D2HGDH) is a mitochondrial enzyme containing flavin adenine dinucleotide FAD, existing as a dimer, and it facilitates the specific oxidation of D-2HG to 2-oxoglutarate (2-OG), which is a key intermediate in the tricarboxylic acid (TCA) cycle. A Genome-wide expression analysis (GWEA) has indicated an association between GhD2HGDH and flowering time. To further explore the role of GhD2HGDH, we performed a comprehensive investigation encompassing phenotyping, physiology, metabolomics, and transcriptomics in Arabidopsis thaliana plants overexpressing GhD2HGDH. Transcriptomic and qRT-PCR data exhibited heightened expression of GhD2HGDH in upland cotton flowers. Additionally, early-maturing cotton exhibited higher expression of GhD2HGDH across all tissues than delayed-maturing cotton. Subcellular localization confirmed its presence in the mitochondria. Overexpression of GhD2HGDH in Arabidopsis resulted in early flowering. Using virus-induced gene silencing (VIGS), we investigated the impact of GhD2HGDH on flowering in both early- and delayed-maturing cotton plants. Manipulation of GhD2HGDH expression levels led to changes in photosynthetic pigment and gas exchange attributes. GhD2HGDH responded to gibberellin (GA3) hormone treatment, influencing the expression of GA biosynthesis genes and repressing DELLA genes. Protein interaction studies, including yeast two-hybrid, luciferase complementation (LUC), and GST pull-down assays, confirmed the interaction between GhD2HGDH and GhSOX (Sulfite oxidase). The metabolomics analysis demonstrated GhD2HGDH's modulation of the TCA cycle through alterations in various metabolite levels. Transcriptome data revealed that GhD2HGDH overexpression triggers early flowering by modulating the GA3 and photoperiodic pathways of the flowering core factor genes. Taken together, GhD2HGDH positively regulates the network of genes associated with early flowering pathways.


Assuntos
Flores , Giberelinas , Gossypium , Fotoperíodo , Proteínas de Plantas , Arabidopsis/genética , Transporte de Elétrons , Flores/genética , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Gossypium/genética , Gossypium/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas
3.
BMC Cancer ; 23(1): 782, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612616

RESUMO

BACKGROUND: The association between gastrointestinal cancer and types of meat consumption, including red meat, processed meat, or a combination of both, remains disputable. Therefore, we performed a systematic review and meta-analysis of prospective cohort studies to estimate the association between meat consumption and gastrointestinal cancer risk. METHODS: PubMed, EmBase, and the Cochrane library databases were searched systematically for eligible studies that investigated the relation between meat consumption and the risk of developing gastrointestinal cancers, including esophageal cancer (EC), gastric cancer (GC), colorectal cancer (CRC), colon cancer (CC), rectal cancer (RC), pancreatic cancer (PC), and hepatocellular carcinoma (HCC) throughout February, 2023. The pooled relative risk (RR) with 95% confidence interval (CI) was assigned as an effect estimate and calculated using a random-effects model with inverse variance weighting. RESULTS: Forty cohorts comprising 3,780,590 individuals were selected for the final quantitative analysis. The summary results indicated that a higher red meat consumption was associated with an increased risk of CRC (RR: 1.09; 95% CI: 1.02-1.16; P = 0.007) and CC (RR: 1.13; 95% CI: 1.03-1.25; P = 0.011). Moreover, a higher processed meat consumption was associated with an increased risk of CRC (RR: 1.19; 95% CI: 1.13-1.26; P < 0.001), CC (RR: 1.24; 95% CI: 1.13-1.26; P < 0.001), and RC (RR: 1.24; 95% CI: 1.08-1.42; P = 0.002). Furthermore, a higher total consumption of red and processed meat was associated with an increased risk of CRC (RR: 1.13; 95% CI: 1.06-1.20; P < 0.001), CC (RR: 1.17; 95% CI: 1.04-1.33; P = 0.012), and RC (RR: 1.20; 95% CI: 1.04-1.39; P = 0.016). Finally, the strength of higher consumption of total red and processed meat with the risk of GC, and higher consumption of red meat with the risk of RC in subgroup of high adjusted level was lower than subgroup of moderate adjusted level, while the strength of higher consumption of processed meat with the risk of RC and HCC in subgroup of follow-up ≥ 10.0 years was higher than subgroup of follow-up < 10.0 years. CONCLUSIONS: This study found that meat consumption was associated with an increased risk of CRC, CC, and RC, and dietary intervention could be considered an effective strategy in preventing CRC.


Assuntos
Carcinoma Hepatocelular , Neoplasias do Colo , Neoplasias Gastrointestinais , Neoplasias Hepáticas , Neoplasias Gástricas , Humanos , Estudos Prospectivos , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/etiologia , Carne/efeitos adversos
4.
Small ; 18(19): e2107881, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35417059

RESUMO

In contrast to the 2D organic-inorganic hybrid Ruddlesden-Popper halide perovskites (RPP), a new class of 2D all inorganic RPP (IRPP) has been recently proposed by substituting the organic spacers with an optimal inorganic alternative of cesium cations (Cs+ ). Nevertheless, the synthesis of high-membered 2D IRPPs (n > 1) has been a very challenging task because the Cs+ need to act as both spacers and A-site cations simultaneously. This work presents the successful synthesis of stable phase-pure high-membered 2D IRPPs of Csn+1 Pbn Br3n+1 nanosheets (NSs) with n = 3 and 4 by employing the strategy of using additional strong binding bidentate ligands. The structures of the 2D IRPPs (n = 3 and 4) NSs are confirmed by powder X-ray diffraction and high-resolution aberration-corrected scanning transmission electron microscope measurements. These 2D IRPPs NSs exhibit a strong quantum confinement effect with tunable absorption and emission in the visible light range by varying their n values, attributed to their inherent 2D quantum-well structure. The superior structural and optical stability of the phase-pure high-membered 2D IRPPs make them a promising candidate as photocatalysts in CO2 reduction reactions with outstanding photocatalytic performance and long-term stability.

5.
Nature ; 520(7547): 325-8, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-25849777

RESUMO

The development of new rechargeable battery systems could fuel various energy applications, from personal electronics to grid storage. Rechargeable aluminium-based batteries offer the possibilities of low cost and low flammability, together with three-electron-redox properties leading to high capacity. However, research efforts over the past 30 years have encountered numerous problems, such as cathode material disintegration, low cell discharge voltage (about 0.55 volts; ref. 5), capacitive behaviour without discharge voltage plateaus (1.1-0.2 volts or 1.8-0.8 volts) and insufficient cycle life (less than 100 cycles) with rapid capacity decay (by 26-85 per cent over 100 cycles). Here we present a rechargeable aluminium battery with high-rate capability that uses an aluminium metal anode and a three-dimensional graphitic-foam cathode. The battery operates through the electrochemical deposition and dissolution of aluminium at the anode, and intercalation/de-intercalation of chloroaluminate anions in the graphite, using a non-flammable ionic liquid electrolyte. The cell exhibits well-defined discharge voltage plateaus near 2 volts, a specific capacity of about 70 mA h g(-1) and a Coulombic efficiency of approximately 98 per cent. The cathode was found to enable fast anion diffusion and intercalation, affording charging times of around one minute with a current density of ~4,000 mA g(-1) (equivalent to ~3,000 W kg(-1)), and to withstand more than 7,500 cycles without capacity decay.

6.
Small ; 16(45): e2002885, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32945097

RESUMO

High demand for green ecosystems has urged the human community to reconsider and revamp the traditional way of synthesis of several compounds. Ammonia (NH3 ) is one such compound whose applications have been extended from fertilizers to explosives and is still being synthesized using the high energy inhaling Haber-Bosch process. Carbon free electrocatalytic nitrogen reduction reaction (NRR) is considered as a potential replacement for the Haber-Bosch method. However, it has few limitations such as low N2 adsorption, selectivity (competitive HER reactions), low yield rate etc. Since it is at the early stage, tremendous efforts have been devoted in understanding the reaction mechanism and screening of the electrocatalysts and electrolytes. In this review, the electrocatalysts are classified based on the periodic table with heat maps of Faraday efficiency and yield rate of NH3 in NRR and their electrocatalytic properties toward NRR are discussed. Also, the activity of each element is discussed and short tables and concise graphs are provided to enable the researchers to understand recent progress on each element. At the end, a perspective is provided on countering the current challenges in NRR. This review may act as handbook for basic NRR understandings, recent progress in NRR, and the design and development of advanced electrocatalysts and systems.

7.
Phys Chem Chem Phys ; 22(43): 24842-24855, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33125020

RESUMO

Global population explosion has led to the rapid revolution of science and technology, and the high energy demand has necessitated new and efficient energy conversion and storage systems. Lithium ion batteries (LIBs) have a high potential window, high capacity, and high stability, but suffer from high cost and low safety. Therefore, many alternative batteries, including sodium ion batteries (NIBs), potassium (KIBs), aluminum (AIBs), and dual ion batteries (DIBs), have been introduced. One of the key working principles of these batteries is based on cation or anion intercalation in the graphite layers, and leads to the formation of graphite intercalation compounds (GICs). Recently, studies based on determining a reaction mechanism to improve the performance of the batteries have been conducted. In this review, an overview of the work on the reaction mechanism of polyatomic ions intercalated into GICs, the structure of intercalated polyatomic ions, the structure of the accommodated GICs, and their staging is provided. In other words, this review focuses on unraveling and understanding the reaction mechanisms for the intercalation of polyatomic ions into GICs by in situ and ex situ techniques, correlated with computational studies. The current limitations and future prospects of polyatomic ions intercalation batteries are also discussed.

8.
Small ; 15(49): e1904723, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31657122

RESUMO

The generation of ammonia, hydrogen production, and nitrogen purification are considered as energy intensive processes accompanied with large amounts of CO2 emission. An electrochemical method assisted by photoenergy is widely utilized for the chemical energy conversion. In this work, earth-abundant iron pyrite (FeS2 ) nanocrystals grown on carbon fiber paper (FeS2 /CFP) are found to be an electrochemical and photoactive catalyst for nitrogen reduction reaction under ambient temperature and pressure. The electrochemical results reveal that FeS2 /CFP achieves a high Faradaic efficiency (FE) of ≈14.14% and NH3 yield rate of ≈0.096 µg min-1 at -0.6 V versus RHE electrode in 0.25 m LiClO4 . During the electrochemical catalytic reaction, the crystal structure of FeS2 /CFP remains in the cubic pyrite phase, as analyzed by in situ X-ray diffraction measurements. With near-infrared laser irradiation (808 nm), the NH3 yield rate of the FeS2 /CFP catalyst can be slightly improved to 0.1 µg min-1 with high FE of 14.57%. Furthermore, density functional theory calculations demonstrate that the N2 molecule has strong chemical adsorption energy on the iron atom of FeS2 . Overall, iron pyrite-based materials have proven to be a potential electrocatalyst with photoactive behavior for ammonia production in practical applications.

9.
Anal Bioanal Chem ; 411(13): 2793-2802, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30931506

RESUMO

A powerful technique to detect bone biomarkers has been developed for assessment of osteoporosis at the early stage. Two-dimensional multilayered gold-nanoparticle thin film (MTF-AuNPs) was demonstrated as a promising test platform for detection of bone biomarker, hydroxyproline (HYP), measured by surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). With strong surface plasmon resonance and excellent homogeneity, facilely prepared, highly ordered, and large-scale MTF-AuNPs revealed high sensitivity of HYP in the SALDI-MS measurement without additional matrixes, such as α-cyano-4-hydroxycinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB). Furthermore, the mass spectrum of HYP with MTF-AuNPs was significantly improved in signal intensity enhancement, background noise reduction, and signal-to-noise ratio amplification. The excellent reproducibility of HYP spectra with only 9.3% relative signal variation could be attributed to MTF-AuNPs' high absorbance at a wavelength of 337 nm, low heat capacity, superior thermal conductivity, and outstanding homogeneity. The calibration curve showed high linear correlation between mass spectrum intensity and HYP concentration in the range of 1 to 100 µM, covering the whole level in healthy people and osteoporosis patients. In particular, the serum sample was directly deposited onto the MTF-AuNP sample substrate without any pretreatment and its HYP concentration was then successfully determined. We believe that the combination of SALDI-MS and MTF-AuNP sample substrates would be a potential approach for bone biomarker detection in the osteoporosis risk assessment. Graphical abstract.


Assuntos
Biomarcadores/sangue , Ouro/química , Nanopartículas Metálicas/química , Osteoporose/sangue , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Biomarcadores/análise , Humanos , Hidroxiprolina/sangue , Limite de Detecção , Nanopartículas Metálicas/ultraestrutura , Osteoporose/diagnóstico , Reprodutibilidade dos Testes , Medição de Risco
10.
Int J Hyperthermia ; 36(sup1): 74-82, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31795830

RESUMO

Purpose: To characterize the T cell receptor (TCR) repertoire, serum cytokine levels, peripheral blood T lymphocyte populations, safety, and clinical efficacy of hyperthermia (HT) combined with autologous adoptive cell therapy (ACT) and either salvage chemotherapy (CT) or anti-PD-1 antibody in patients with previously treated advanced solid tumors.Materials and methods: Thirty-three (33) patients with ovarian, pancreatic, gastric, colorectal, cervical, or endometrial cancer were recruited into the following therapeutic groups: HT + ACT (n = 10), HT + ACT + anti-PD-1 inhibitor (pembrolizumab) (n = 11) and HT + ACT + CT (n = 12). Peripheral blood was collected to analyze TCR repertoire, measurements of cytokines levels and lymphocyte sub-populations before and after treatment.Results: The objective response rate (ORR) was 30% (10/33), including three complete responses (CR) (9.1%) and seven partial responses (PR) (21.2%) and a disease control rate (DCR = CR + PR + SD) of 66.7% (22 of 33). The most common adverse reactions, blistering, subcutaneous fat induration, local heat-related pain, vomiting and sinus tachycardia, were observed in association with HT. IL-2, IL-4, TNF-α, and IFN-γ levels in peripheral blood were significantly increased among the clinical responders (p < 0.05) while IL-6 and IL-10 were elevated among those with progressive disease (p < 0.05). Peripheral blood CD8+/CD28+ T cells increased (p = 0.002), while the CD4+/CD25+/CD127+Treg cells decreased after therapy (p = 0.012). TCR diversity was substantially increased among the clinical responders.Conclusions: Combining HT with ACT plus either CT or anti-PD-1 antibody was safe, generated clinical responses in previously treated advanced cancers, and promoted TCR repertoire diversity and favorable changes in serum IL-2, IL-4, TNF-α, and IFN-γ levels in clinical responders.


Assuntos
Hipertermia Induzida/métodos , Imunoterapia Adotiva/métodos , Neoplasias/terapia , Adolescente , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem
11.
Yi Chuan ; 41(3): 215-233, 2019 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-30872258

RESUMO

Mammalian genomic DNA in the cell nucleus doesn't exist in linear form but is highly folded and condensed into chromatin with a three-dimensional (3D) structure possessing a specific spatial structure and conformation. Hi-C, the high-throughput chromosome conformation capture technology, was first published in 2009, and it provides an in-depth view of 3D genomics. According to the size of DNA unit, the 3D hierarchical units of mammalian genome can be categorized sequentially as chromosome territory (CT), chromatin compartment A/B, topological associated domain (TAD), and chromatin loop. These hierarchical structural units play vital roles in gene transcription and regulation. In this review, we summarize the 3D hierarchical division of chromosomes, the effects of hierarchical units and the applications of Hi-C technology in development and disease. This review is intended to provide insights for the further study of 3D genomics in mammals.


Assuntos
Cromatina , Cromossomos , Genoma , Mamíferos/genética , Animais , Genômica , Conformação de Ácido Nucleico
12.
Anal Chem ; 90(6): 3974-3980, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29466668

RESUMO

The glucose metabolism rate in cancer cells is a crucial piece of information for the cancer aggressiveness. A feasible method to monitor processes of oncogenic mutations has been demonstrated in this work. The fluorescent gold nanoclusters conjugated with glucose (glucose-AuNCs) were successfully synthesized as a cancer-targeting probe for glucose transporters (Gluts) overexpressed by U-87 MG cancer cells, which can be observed under confocal microscopy. The structural and optical characterizations of fluorescent glucose-AuNCs were confirmed by transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). The MTT assay exhibited the high biocompatibility of water-soluble glucose-AuNCs for further biomedical applications. The glucose metabolic cleavage of glucose-AuNCs by glycolytic enzymes from U-87 MG cancer cell was measured by fluorescence change of glucose-AuNCs. The fluorescence change based on the integrated area under fluorescence spectra ( A t) of glucose-AuNCs was plotted as a function of different reaction time ( t) with glycolytic enzymes. The fitted curve of A t versus t showed the first-order kinetics to explain the mechanism of glucose metabolic cleavage rate of glucose-AuNCs by glycolytic enzymes. The rate constant k could be utilized to determine the glucose metabolism rate of glucose-AuNCs for the quantitative analysis of cancer aggressiveness. Our work provides a practical application of target-specific glucose-AuNCs as a fluorescence probe to analyze the glucose metabolism in Gluts overexpressed cancer cells.


Assuntos
Corantes Fluorescentes/química , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Glucose/metabolismo , Glicólise , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/metabolismo , Técnicas Biossensoriais/métodos , Linhagem Celular Tumoral , Glucose/química , Proteínas Facilitadoras de Transporte de Glucose/análise , Humanos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Neoplasias/enzimologia
13.
Clin Lab ; 64(7): 1233-1240, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30146825

RESUMO

BACKGROUND: To evaluate the performance of a chemiluminescence detection reagent for Neuron-specific enolase (NSE). METHODS: Based on the "Guiding principles on performance analysis of diagnostic, reagents in vitro" and the Clinical and Laboratory Standards Institute (CLSI) Guidelines, performance of the CLIA NSE kit was evaluated, including the detection limit, linear range, reportable range, accuracy, precision, cross reactivity, interference factors, Hook effect, and method comparison. RESULTS: The detection limit of the reagent was 0.05 ng/mL. The linear range of the reagent was 0.05 ng/mL - 400 ng/mL. The reagent can be reported as 0.05 ng/mL - 2,500 ng/mL. The recovery rate ranged from 94.95% to 105.12%. The CV of the reagent of the intra-assay was 3.8% - 5.7% and inter-batch was 3.6%, which meets the requirements. The common interference factors such as the blood fat, jaundice, and rheumatoid factor did not affect the quantitative accuracy of the reagent, but hemolysis resulted in higher readings. Cross-reactions were not observed when incubating with major interfering tumor markers; therefore, the kit was highly specific for NSE. The HOOK effect was not observed when the NSE content reached 20,000 ng/mL in samples. The coincidence rate of the reagent and Roche's products reached 94.81% and the correlation r reached 0.968. CONCLUSIONS: The performance of the NSE CLIA reagent was acceptable in all evaluated parameters, meeting requirements for clinical application.


Assuntos
Guias como Assunto/normas , Medições Luminescentes/normas , Fosfopiruvato Hidratase/sangue , Kit de Reagentes para Diagnóstico/normas , Humanos , Limite de Detecção , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Reprodutibilidade dos Testes
14.
J Clin Lab Anal ; 32(4): e22363, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29168576

RESUMO

BACKGROUND: Neoadjuvant chemotherapy has been widely applied in treating advanced gastric cancer (GC). However, little research has been conducted on evaluating the effect of neoadjuvant chemotherapy. Purpose of this study was to evaluate the effect of SOX regimen as neoadjuvant chemotherapy by detecting some microRNAs. METHODS: Total 120 GC patients who had received neoadjuvant chemotherapy (SOX regimen) were recruited with 100 healthy participants as control contemporarily. Age and gender have no significant difference in both groups (P > .05). The effect of chemotherapy was evaluated by the results of CT scan and surgery. Also, adverse effects of chemotherapy were documented. Peripheral blood of GC patients was collected twice: one day before chemotherapy and surgery, respectively, whereas healthy controls' peripheral blood was collected once. Quantitative real-time PCR (qPCR) was utilized to detect expression of miR-145, miR-185, miR-381, and miR-195 of peripheral blood in both groups. RESULTS: One hundred and twenty patients with advanced GC completed a total of 386 cycles of neoadjuvant chemotherapy with effective rate at 84.17% (101 of 120). Expression of miR-145, miR-185, and miR-381 of patients with GC was lower than that in the control group before chemotherapy commence (all P < .05), while the expressions of miR-145 and miR-185 elevated noticeably in CG patients after neoadjuvant chemotherapy (P < .05). The differences in the expression of miR-145 and miR-185 in advanced GC patients with different chemotherapy outcomes were detected. CONCLUSION: Patients with GC at advanced stages had aberrant miRs expressions. Detection of miR-145 and miR-185 expression may assist to predict effectiveness and adverse effects of SOX regimen as neoadjuvant chemotherapy.


Assuntos
MicroRNAs/sangue , Terapia Neoadjuvante , Neoplasias Gástricas/sangue , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Gástricas/epidemiologia
15.
Small ; 13(8)2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27982540

RESUMO

Hydrogen is considered as sustainable and environmentally friendly energy for global energy demands in the future. Here a Co-FeS2 catalyst with surface phosphide doping (P/Co-FeS2 ) for hydrogen evolution reaction (HER) in acidic solutions is developed. The P/Co-FeS2 exhibits superior HER electrochemical performance with overpotential of -90 mV at 100 mA cm-2 and Tafel slope of 41 mV/decade and excellent durability.

16.
J Am Chem Soc ; 137(4): 1587-92, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25588180

RESUMO

Hydrogen evolution reaction (HER) from water through electrocatalysis using cost-effective materials to replace precious Pt catalysts holds great promise for clean energy technologies. In this work we developed a highly active and stable catalyst containing Co doped earth abundant iron pyrite FeS(2) nanosheets hybridized with carbon nanotubes (Fe(1-x)CoxS(2)/CNT hybrid catalysts) for HER in acidic solutions. The pyrite phase of Fe(1-x)CoxS(2)/CNT was characterized by powder X-ray diffraction and absorption spectroscopy. Electrochemical measurements showed a low overpotential of ∼0.12 V at 20 mA/cm(2), small Tafel slope of ∼46 mV/decade, and long-term durability over 40 h of HER operation using bulk quantities of Fe(0.9)Co(0.1)S(2)/CNT hybrid catalysts at high loadings (∼7 mg/cm(2)). Density functional theory calculation revealed that the origin of high catalytic activity stemmed from a large reduction of the kinetic energy barrier of H atom adsorption on FeS(2) surface upon Co doping in the iron pyrite structure. It is also found that the high HER catalytic activity of Fe(0.9)Co(0.1)S(2) hinges on the hybridization with CNTs to impart strong heteroatomic interactions between CNT and Fe(0.9)Co(0.1)S(2). This work produces the most active HER catalyst based on iron pyrite, suggesting a scalable, low cost, and highly efficient catalyst for hydrogen generation.

17.
Anal Chem ; 87(17): 8765-71, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26255581

RESUMO

We present a novel method for high precision measurement of (186)Os/(188)Os and (187)Os/(188)Os ratios, applying isobaric oxide interference correction based on in-run measurements of oxygen isotopic ratios. For this purpose, we set up a static data collection routine to measure the main Os(16)O3(-) ion beams with Faraday cups connected to conventional 10(11) amplifiers, and (192)Os(16)O2(17)O(-) and (192)Os(16)O2(18)O(-) ion beams with Faraday cups connected to 10(12) amplifiers. Because of the limited number of Faraday cups, we did not measure (184)Os(16)O3(-) and (189)Os(16)O3(-) simultaneously in-run, but the analytical setup had no significant influence on final (186)Os/(188)Os and (187)Os/(188)Os data. By analyzing UMd, DROsS, an in-house Os solution standard, and several rock reference materials, including WPR-1, WMS-1a, and Gpt-5, the in-run measured oxygen isotopic ratios were proven to present accurate Os isotopic data. However, (186)Os/(188)Os and (187)Os/(188)Os data obtained with in-run O isotopic compositions for the solution standards and rock reference materials show minimal improvement in internal and external precision, compared to the conventional oxygen correction method. We concluded that, the small variations of oxygen isotopes during OsO3(-) analytical sessions are probably not the main source of error for high precision Os isotopic analysis. Nevertheless, use of run-specific O isotopic compositions is still a better choice for Os isotopic data reduction and eliminates the requirement of extra measurements of the oxygen isotopic ratios.

18.
Small ; 11(24): 2929-37, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-25703342

RESUMO

Energy scavenging has become a fundamental part of ubiquitous sensor networks. Of all the scavenging technologies, solar has the highest power density available. However, the energy source is erratic. Integrating energy conversion and storage devices is a viable route to obtain self-powered electronic systems which have long-term maintenance-free operation. In this work, we demonstrate an integrated-power-sheet, consisting of a string of series connected organic photovoltaic cells (OPCs) and graphene supercapacitors on a single substrate, using graphene as a common platform. This results in lighter and more flexible power packs. Graphene is used in different forms and qualities for different functions. Chemical vapor deposition grown high quality graphene is used as a transparent conductor, while solution exfoliated graphene pastes are used as supercapacitor electrodes. Solution-based coating techniques are used to deposit the separate components onto a single substrate, making the process compatible with roll-to-roll manufacture. Eight series connected OPCs based on poly(3-hexylthiophene)(P3HT):phenyl-C61-butyric acid methyl ester (PC60 BM) bulk-heterojunction cells with aluminum electrodes, resulting in a ≈5 V open-circuit voltage, provide the energy harvesting capability. Supercapacitors based on graphene ink with ≈2.5 mF cm(-2) capacitance provide the energy storage capability. The integrated-power-sheet with photovoltaic (PV) energy harvesting and storage functions had a mass of 0.35 g plus the substrate.

19.
Antonie Van Leeuwenhoek ; 108(5): 1161-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26346479

RESUMO

A Gram-stain negative, motile, rod-shaped bacterium, designated strain YIM Hb-3(T), was isolated from the stem of a tobacco plant. The strain was observed to form convex, circular and yellow-colored colonies. The predominant respiratory quinone was identified as Q-8. The major fatty acids (>5%) detected were C(16:1)ω7c and/or C(16:1)ω6c (summed feature 3), C(16:0), C(17:0)cyclo, C(18:1)ω7c and/or C(18:1)ω6c (summed feature 8), C(14:0)3-OH and/or iso-C(16:1)I (summed feature 2), C(14:0) and C(12:0). The genomic DNA G+C content was determined to be 54.8 mol%. Phylogenetic trees based on 16S rRNA gene sequences and multilocus sequence analysis showed that strain YIM Hb-3(T) had the closest phylogenetic relationship with Enterobacter mori LMG 25706(T). DNA-DNA relatedness value between strain YIM Hb-3(T) and E. mori LMG 25706(T) was 46.9 ± 3.8%. On the basis of phenotypic and chemotaxonomic data, phylogenetic analysis, and DNA-DNA relatedness value, strain YIM Hb-3(T) is considered to represent a novel species of the genus Enterobacter, for which the name Enterobacter tabaci sp. nov. is proposed. The type strain is YIM Hb-3(T) (=KACC 17832(T) =KCTC 42694(T)).


Assuntos
Enterobacter/classificação , Nicotiana/microbiologia , Caules de Planta/microbiologia , Enterobacter/química , Enterobacter/genética , Enterobacter/isolamento & purificação , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética
20.
Asian-Australas J Anim Sci ; 28(6): 782-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25925055

RESUMO

The myogenic regulatory factors is a family of transcription factors that play a key role in the development of skeletal muscle fibers, which are the main factors to affect the meat taste and texture. In the present study, we performed candidate gene analysis to identify single-nucleotide polymorphisms in the MyoD, Myf5, MyoG, and Mrf4 genes using polymerase chain reaction-single strand conformation polymorphism in 360 Erlang Mountain Chickens from three different housing systems (cage, pen, and free-range). The general linear model procedure was used to estimate the statistical significance of association between combined genotypes and muscle fiber traits of chickens. Two polymorphisms (g.39928301T>G and g.11579368C>T) were detected in the Mrf4 and MyoD gene, respectively. The diameters of thigh and pectoralis muscle fibers were higher in birds with the combined genotypes of GG-TT and TT-CT (p<0.05). Moreover, the interaction between housing system and combined genotypes has no significant effect on the traits of muscle fiber (p>0.05). Our findings suggest that the combined genotypes of TT-CT and GG-TT might be advantageous for muscle fiber traits, and could be the potential genetic markers for breeding program in Erlang Mountain Chickens.

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