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1.
Discov Med ; 36(180): 91-99, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273749

RESUMO

BACKGROUND: Dysphagia is a prevalent complication following partial laryngectomy. We aimed to introduce a novel bedside evaluation tool, the modified Gugging Swallowing Screen (GUSS), and evaluate its reliability and validity in patients with open partial laryngectomy before oral feeding. METHODS: We conducted a retrospective analysis of 120 patients with laryngeal cancer, including 40 hospitalized patients who underwent open partial laryngectomy. On the same day before oral feeding, we performed the modified GUSS, videofluoroscopic swallowing study (VFSS), and fiberoptic endoscopic evaluation of swallowing (FEES) to evaluate swallowing function. Two independent trained nurses assessed all patients for interrater reliability of modified GUSS. We compared the results of the modified GUSS with VFSS for predictive validity, and VFSS results for solid, semisolid, and liquid intake for content validity. RESULTS: The results of VFSS and FEES showed a strong correlation and consistency (rs = 0.952, p < 0.01; κ = 0.800 to 1.000, p < 0.01). The modified GUSS exhibited substantial to excellent interrater reliability across all classification categories (rs = 0.961, p < 0.01; κ = 0.600 to 1.000, p < 0.01) and demonstrated excellent consistency and predictive validity compared to VFSS (rs = -0.931, p < 0.01; κ = 0.800 to 1.000, p < 0.01). Content validity revealed that the risk of aspiration during solid intake was lower than that during semisolid intake (p < 0.01), and the risk of aspiration during semisolid intake was lower than that during liquid intake (p < 0.01), therefore confirming the subtest sequence of the modified GUSS. CONCLUSIONS: We successfully modified GUSS for patients with open partial laryngectomy. Moreover, the new bedside screening tool was validated as an effective tool for evaluating swallowing function and the risk of aspiration in patients with open partial laryngectomy before oral feeding.


Assuntos
Transtornos de Deglutição , Deglutição , Humanos , Estudos Retrospectivos , Laringectomia/efeitos adversos , Laringectomia/métodos , Reprodutibilidade dos Testes , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia
2.
Water Res ; 247: 120808, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37924684

RESUMO

Dissolved inorganic carbon (DIC) represents a major global carbon pool and the flux from rivers to oceans has been observed to be increasing. The effect of weathering with respect to increasing DIC has been widely studied in recent decades; however, the influence of dissolved organic matter (DOM) on increasing DIC in large rivers remains unclear. This study employed stable carbon isotopes and Fourier transform ion cyclotron mass spectrometry (FT-ICR MS) to investigate the effect of the molecular composition of DOM on the DIC in the Yangtze River. The results showed that organic matter is an important source of DIC in the Yangtze River, accounting for 40.0 ± 12.1 % and 32.0 ± 7.2 % of DIC in wet and dry seasons, respectively, and increased along the river by approximately three times. Nitrogen (N)-containing DOM, an important composition in DOM with a percentage of ∼40 %, showed superior oxidation state than non N-containing DOM, suggesting that the presence of N could improve the degradable potential of DOM. Positive relationship between organic sourced DIC (DICOC) and N-containing DOM formulae indicated that N-containing DOM is crucial to facilitate the mineralization of DOM to DICOC. N-containg molecular formular with low H/C and O/C ratio were positively correlated with DICOC further verified these energy-rich and biolabile compounds are preferentially decomposed by bacteria to produce DIC. N-containing components significantly accelerated the degradation of DOM to DICOC, which is important for understanding the CO2 emission and carbon cycling in large rivers.


Assuntos
Matéria Orgânica Dissolvida , Rios , Rios/química , Isótopos de Carbono , Espectrometria de Massas , China , Nitrogênio , Carbono
3.
Angew Chem Int Ed Engl ; 62(31): e202306495, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37277694

RESUMO

Porous liquids (PLs), a summation of porous hosts and bulky solvents bestowing permanent cavities, are the prominent emerging materials. Despite great efforts, exploration of porous hosts and bulky solvents is still needed to develop new PL systems. Metal-organic polyhedra (MOPs) with discrete molecular architectures can be considered as porous hosts; however, many of them are insoluble entities. Here we report the transformation of type III PL to type II PLs by tuning the surface rigidity of insoluble MOP, Rh24 L24 , in a bulky ionic liquid (IL). Functionalization of N-donor molecules on Rh-Rh axial sites ensue their solubilization in bulky IL which confer type II PLs. Experimental and theoretical studies reveal the bulkiness of IL as per the cage apertures, and the cause of their dissolution as well. The obtained PLs, capturing more CO2 than neat solvent, have depicted higher catalytic activity for CO2 cycloaddition compared to individual MOPs and IL.

4.
Int J Cardiol ; 371: 480-485, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36115439

RESUMO

BACKGROUND: The dynamic changes and apical aneurysm formation in apical hypertrophic cardiomyopathy (HCM) have not been specifically described. This study aimed to describe these changes to better understand the progression of apical HCM. METHODS AND RESULTS: Seventy-two patients with apical HCM who underwent at least two cardiac magnetic resonance (CMR) examinations were retrospectively included in this study. The mean interval between the first and last CMR examinations was 50.1 ± 26.8 months (ranging from 4 to 118 months). Compared with the initial values, the left atrial diameter, maximum left ventricular wall thickness and late gadolinium enhancement extent significantly increased (all P < 0.05), while the left ventricular ejection fraction significantly decreased (P < 0.05), at the latest CMR examination. More importantly, the dynamic process of apical aneurysm formation in apical HCM was observed in a subset of patients, which may follow these four stages: starting with systolic apical cavity obliteration, then broadening of the apical slit in systole, further developing into an apical outpouching, and finally forming an apical aneurysm. Eleven patients experienced adverse cardiovascular events, including new-onset or progressive atrial fibrillation (n = 7), hospitalization with heart failure (n = 3) and implantable cardioverter defibrillator intervention (n = 1), at the time of the latest CMR examination. CONCLUSIONS: In the progression of apical HCM, cardiac structure and function will change accordingly. Apical aneurysm formation in apical HCM is a chronic and continuous dynamic process that may follow a 4-step pathway of disease progression.


Assuntos
Aneurisma , Miocardiopatia Hipertrófica Apical , Cardiomiopatia Hipertrófica , Humanos , Projetos Piloto , Gadolínio , Meios de Contraste , Função Ventricular Esquerda , Volume Sistólico , Estudos Retrospectivos , Espectroscopia de Ressonância Magnética
5.
Angew Chem Int Ed Engl ; 61(50): e202212326, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36261323

RESUMO

A porous liquid is a unique liquid medium that combines the cavity of porous solids with the fluidity of liquids. This special characteristic offers potential in various applications. Here we report a type II photoresponsive porous ionic liquid (PPIL) from dissolving a photoresponsive metal-organic polyhedron (PMOP, constructed from dicopper and azobenzene-containing carboxylate) in a polyethylene-glycol-functionalized bulky ionic liquid (IL). Owing to favorable ion interactions, bulky IL molecules encircle outside PMOP, and the inter cavities are maintained. The azobenzene moieties can be isomerized freely in the PPILs to expose and shelter active sites upon visible and UV light irradiation. Hence, the adsorption capacity of PPILs is controllable by light irradiation, and the change in CO2 uptake is up to 30 % compared to neat IL. This study may inspire the development of new adsorption process regulated by light instead of pressure and temperature swing adsorption.

6.
Int J Mol Sci ; 23(14)2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35886927

RESUMO

Common wheat (Triticum aestivum L.) is an important food crop with a unique processing quality. The Q gene positively regulates the processing quality of wheat, but the underlying mechanism remains unclear. Here, a new Q allele (Qc5) responsible for compact spikes and good bread performance was identified. Compared with the Q allele widely distributed in modern common wheat cultivars, Qc5 had a missense mutation outside the miRNA172-binding site. This missense mutation led to a more compact messenger RNA (mRNA) secondary structure around the miRNA172-binding region, resulting in increased Qc5 expression during the spike development stage and a consequent increase in spike density. Furthermore, this missense mutation weakened the physical interaction between Qc5 and storage protein activator (SPA) in seeds and suppressed the expression of storage protein repressor (SPR). These changes increased the grain protein content and improved the bread-making quality of wheat. In conclusion, a missense mutation increases Q expression because of the resulting highly folded mRNA secondary structure around the miRNA172-binding site. Furthermore, this mutation improves the bread-making quality of wheat by repressing the expression of SPR and influencing the physical interaction between Q and SPA. These findings provide new insights into the miRNA172-directed regulation of gene expression, with implications for wheat breeding.


Assuntos
Pão , Triticum , Alelos , Pão/análise , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ressonância de Plasmônio de Superfície , Triticum/metabolismo
7.
Inorg Chem ; 61(27): 10393-10401, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35765964

RESUMO

Hierarchically porous metal-organic frameworks (HP-MOFs), dominating both the micro- and mesoporous regimes, show high potentials in various applications especially those involving bulky biomolecules. The templating method has been proven to be effective in the fabrication of HP-MOFs; however, complicated synthetic systems containing solvents, templates, and additives are frequently employed. Here we report the first example of designing a poly(ethylene glycol)-based alkylammonium and bromide multifunctional ionic liquid (IL) as a solitary medium to construct HP-MOFs, avoiding the involvement of any additional media. Besides the ready solubilization of MOF precursors in the multifunctional IL due to a poly(ethylene glycol) chain as the solubilizer, the ionic moiety facilitates electrostatic interaction to create a templating effect. Hence, UiO-66 with hierarchical porosity has been successfully fabricated, and such a methodology can also be applied to the construction of other HP-MOFs. The resultant HP-UiO-66 is efficient in the encapsulation of bulky biomolecule cytochrome c, and the adsorption capacity is obviously superior to that of the microporous counterpart.


Assuntos
Líquidos Iônicos , Estruturas Metalorgânicas , Ácidos Ftálicos , Polietilenoglicóis , Porosidade
8.
J Environ Manage ; 318: 115528, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35724575

RESUMO

Black carbon (BC), the highly recalcitrant aromatic carbonaceous from the incomplete combustion of fossil fuel and biomass, is an important carbon sink in carbon cycle. Char and soot, the main components of BC, have significantly different origin and physicochemical characteristics (particle sizes and resultant transportability). The limited understanding of char and soot sources leads to poor insight into the effect of BC on carbon cycle. Sources of char and soot were investigated in this study using stable carbon isotopes to study the effect of BC on the organic carbon pool in a lake, thereby improving the knowledge of lacustrine carbon cycling. The concentration of BC in Taihu Lake ranged from 0.0 to 0.7 mg·L-1and accounted for 10.9 ± 4.7% of the particulate organic carbon. The spatial-mean δ13C values of BC, char, and soot were -23.2 ± 2.0‰, -23.5 ± 2.2‰, and -22.9 ± 1.6‰, respectively. The BC in water was primarily derived from fossil fuels (66.0 ± 9.3%), with liquid fossil fuel accounting for 48.2 ± 13.2% of the BC. The contribution of liquid fossil fuel to soot (49.3%) was much higher than that to char (36.1%); correspondingly, the contributions of biomass and coal to soot (29.2% and 21.5%) were lower than those to char (38.1% and 25.8%). The contribution of liquid fossil fuel combustion to organic carbon (OC), char, and soot gradually increased from 31.9% to 49.3%. Biomass and coal combustion primarily contributed to char (38.1% and 25.8%) and OC (37.5% and 30.6%). The source apportionment of BC, char, and soot revealed the influence of anthropogenically driven BC, char, and soot on the lake and, by extension, to the global carbon cycle.


Assuntos
Poluentes Atmosféricos , Fuligem , Poluentes Atmosféricos/análise , Carbono/análise , Isótopos de Carbono/análise , China , Carvão Mineral , Poeira , Monitoramento Ambiental , Combustíveis Fósseis , Lagos
9.
ACS Appl Mater Interfaces ; 14(8): 10001-10014, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35172581

RESUMO

Improvement of antitumor effects relies on the development of biocompatible nanomaterials and combination of various therapies to produce synergistic effects and avoid resistance. In this work, we developed GBD-Fe, a nanoformulation that effectively integrated chemotherapy (CT), chemodynamic therapy (CDT), and photothermal therapy (PTT). GBD-Fe used gold nanorods as photothermal agents and encapsulated doxorubicin to amplify Fe3+-guided CDT effects by producing H2O2 and reducing the intracellular glutathione levels. In vitro and in vivo experiments were conducted to demonstrate the enhanced accumulation and antitumor effects of this tripronged therapy under magnetic resonance imaging (MRI) guidance. This tripronged approach of CT/CDT/PTT effectively induced tumor cytotoxicity and inhibited tumor growth in tumor-bearing mice and therefore represents a promising strategy to effectively treat tumors.


Assuntos
Nanotubos , Neoplasias , Animais , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ouro , Peróxido de Hidrogênio , Camundongos , Neoplasias/tratamento farmacológico
10.
Sci Total Environ ; 803: 150057, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34500269

RESUMO

Black carbon (BC), characterized by high aromaticity and stability, has been recognized as a substantial fraction of the carbon pool in soil and sediment. The effect of BC on the particulate organic carbon (POC) pool in lake water, which is an important medium of carbon transmission and transformation, has not been thoroughly studied. The investigations of BC composition and distribution, POC, polycyclic aromatic hydrocarbons (PAHs), and stable carbon and nitrogen isotopes were conducted in a eutrophic urban lake, Taihu Lake, which is the third largest freshwater lake in China. The results indicate that the BC is composed of 55 ± 12% char and 45 ± 12% soot and accounted for 12 ± 6% of POC (the maximum value is 31%). The comparatively high levels of BC and char are distributed in the northern Taihu Lake, especially in Meiliang Bay (0.72 ± 0.38 mg L-1 and 0.45 ± 0.24 mg L-1). The distribution of soot presents a declining trend from the lakeshore to the central lake, particularly in the northern, western, and southern lakes. Source apportionment results from positive matrix factorization of PAHs suggest that consumption of fossil fuel (79 ± 20%) is the dominant source of BC, which agrees with the low ratio of char/soot (1.41 ± 0.71) and relatively depleted δ13C. The covariation of BC and PAHs and terrestrial dissolved organic carbon indicate that the effect of terrestrial input significantly regulates the distribution of BC in Taihu Lake, which is reflected in the high BC value along the lakeshore.


Assuntos
Lagos , Hidrocarbonetos Policíclicos Aromáticos , Carbono/análise , China , Monitoramento Ambiental , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Fuligem/análise
11.
J Colloid Interface Sci ; 611: 193-204, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34953455

RESUMO

Multifunctional phototheranostics combining diagnostic and therapeutic modalities may provide a revolutionary opportunity for cancer treatment. As a promising tumor phototheranostic molecule, IR780 iodide (IR780) shows excellent photodynamic and photothermal performance under near-infrared laser irradiation; however, its hydrophobicity and instability limit its further use in organisms. This work demonstrates the design and development of a multifunctional nanoplatform (PMIDA, referring to polydopamine (PDA)-manganese dioxide (MnO2)-IR780) for imaging-guided phototherapy. The good biocompatibility of PDA greatly improves the water solubility and photostability of IR780, and its excellent photothermal properties make PMIDA a dual photothermal therapy (PTT). MnO2-induced generation of oxygen in the tumor microenvironment improves the hypoxia effect and photodynamic therapy (PDT) of IR780. Moreover, Mn2+ serves as a decent T1-weighted magnetic resonance imaging (MRI) probe to guide treatment. Notably, in relevant cellular assays, PMIDA shows high photodynamic and photothermal effects contributing to the final therapeutic effect. The MRI-guided PDT/PTT synergistic therapy effect in vivo is demonstrated by precise tumor diagnosis and complete tumor elimination outcomes. Based on these experiments, PMIDA nanoparticles display promising effects in facilitating intravenous injection of IR780 and achieving magnetic resonance imaging (MRI)-guided phototheranostic efficacy for tumor treatment.


Assuntos
Nanopartículas , Fotoquimioterapia , Linhagem Celular Tumoral , Indóis , Iodetos , Imageamento por Ressonância Magnética , Compostos de Manganês , Óxidos , Fototerapia , Terapia Fototérmica , Polímeros
13.
Environ Sci Technol ; 55(9): 6467-6475, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33886307

RESUMO

The continuous flux of organic carbon (OC) from terrestrial ecosystems into inland water is an important component of the global carbon cycle. The buried OC pool in inland water sediments is considerable, and black carbon (BC) is a significant contributor to this OC pool because of the continuous growth in BC emissions. Therefore, determining the effect of BC on total OC burial and variations in the structure of BC during the burial process will contribute significantly to our understanding of lacustrine carbon cycling. This study investigated BC burial and its structural variations in response to anthropogenic drivers using four dated sedimentary cores from a deep plateau lake in China. The BC burial rate rose from 0.96 ± 0.64 g·m-2·y-1 (mean of sedimentary cores pre-1960s) to 4.83 ± 1.25 g·m-2·y-1 (after 2000), which is a 5.48 ± 2.12-fold rise. The increase of char was similar to those of BC. The growth rate of soot was 7.20 ± 4.30 times, which is higher than that of BC and char, increasing from 0.12 ± 0.08 to 0.64 ± 0.23 g·m-2·y-1. There was a decreasing trend in the ratio of char and soot at a mean rate of 62.8 ± 6.46% (excluding core 3) in relation to increased fossil fuel consumption. The contribution of BC to OC burial showed a significant increasing trend from the past to the present, particularly in cores 3 and 4, and the mean contribution of the four cores was 11.78 ± 2.84%. Source tracer results from positive matrix factorization confirmed that the substantial use of fossil fuels has promoted BC burial and altered the BC structure. This has resulted in BC with a higher aromatic content in the lake sediment, which exhibits reduced reactivity and increased stability. The strong correlation between BC and allochthonous total OC indicates that the input pathways of the buried BC in this plateau lake sediment were terrestrial surface processes and not atmospheric deposition.


Assuntos
Lagos , Fuligem , Carbono/análise , Sequestro de Carbono , China , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Fuligem/análise
14.
Mol Breed ; 41(8): 49, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37309542

RESUMO

Wheat is a major staple food crop worldwide because of the unique properties of wheat flour. High molecular weight glutenin subunits (HMW-GSs), which are among the most critical determinants of wheat flour quality, are responsible for the formation of glutenin polymeric structures via interchain disulfide bonds. We herein describe the identification of a new HMW-GS Dy10 allele (Dy10-m619SN). The amino acid substitution (serine-to-asparagine) encoded in this allele resulted in a partial post-translational cleavage that produced two new peptides. These new peptides disrupted the interactions among gluten proteins because of the associated changes to the number of available cysteine residues for interchain disulfide bonds. Consequently, Dy10-m619SN expression decreased the size of glutenin polymers and weakened glutens, which resulted in wheat dough with improved cookie-making quality, without changes to the glutenin-to-gliadin ratio. In this study, we clarified the post-translational processing of HMW-GSs and revealed a new genetic resource useful for wheat breeding. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01238-9.

15.
Science ; 367(6483): 1218-1223, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32165582

RESUMO

Spin ices are exotic phases of matter characterized by frustrated spins obeying local "ice rules," in analogy with the electric dipoles in water ice. In two dimensions, one can similarly define ice rules for in-plane Ising-like spins arranged on a kagome lattice. These ice rules require each triangle plaquette to have a single monopole and can lead to different types of orders and excitations. Using experimental and theoretical approaches including magnetometry, thermodynamic measurements, neutron scattering, and Monte Carlo simulations, we establish HoAgGe as a crystalline (i.e., nonartificial) system that realizes the kagome spin ice state. The system features a variety of partially and fully ordered states and a sequence of field-induced phases at low temperatures, all consistent with the kagome ice rule.

16.
Toxins (Basel) ; 11(11)2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671876

RESUMO

Fusarium graminearum causes Fusarium head blight (FHB), a devastating disease of wheat. Salicylic acid (SA) is involved in the resistance of wheat to F. graminearum. Cell wall mannoprotein (CWM) is known to trigger defense responses in plants, but its role in the pathogenicity of F. graminearum remains unclear. Here, we characterized FgCWM1 (FG05_11315), encoding a CWM in F. graminearum. FgCWM1 was highly expressed in wheat spikes by 24 h after initial inoculation and was upregulated by SA. Disruption of FgCWM1 (ΔFgCWM1) reduced mannose and protein accumulation in the fungal cell wall, especially under SA treatment, and resulted in defective fungal cell walls, leading to increased fungal sensitivity to SA. The positive role of FgCWM1 in mannose and protein accumulation was confirmed by its expression in Saccharomyces cerevisiae. Compared with wild type (WT), ΔFgCWM1 exhibited reduced pathogenicity toward wheat, but it produced the same amount of deoxynivalenol both in culture and in spikes. Complementation of ΔFgCWM1 with FgCWM1 restored the WT phenotype. Localization analyses revealed that FgCWM1 was distributed on the cell wall, consistent with its structural role. Thus, FgCWM1 encodes a CWM protein that plays an important role in the cell wall integrity and pathogenicity of F. graminearum.


Assuntos
Parede Celular/química , Parede Celular/genética , Resistência à Doença/genética , Fusarium/genética , Interações Hospedeiro-Patógeno/genética , Glicoproteínas de Membrana/genética , Virulência/genética , Sequência de Aminoácidos , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Ácido Salicílico/química , Triticum/microbiologia
17.
J Phys Condens Matter ; 30(21): 214001, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29651997

RESUMO

In this work, a novel compound Ba9V3Se15 with one-dimensional (1D) spin chains was synthesized under high-pressure and high-temperature conditions. It was systematically characterized via structural, magnetic, thermodynamic and transport measurements. Ba9V3Se15 crystallizes into a hexagonal structure with a space group of P-6c2 (188) and the lattice constants of a = b = 9.5745(7) Å and c = 18.7814(4) Å. The crystal structure consists of face-sharing octahedral VSe6 chains along c axis, which are trimeric and arranged in a triangular lattice in ab-plane. Ba9V3Se15 is a semiconductor and undergoes complex magnetic transitions. In the zero-field-cooled (ZFC) process with magnetic field of 10 Oe, Ba9V3Se15 sequentially undergoes ferrimagnetic and spin cluster glass transition at 2.5 K and 3.3 K, respectively. When the magnetic field exceeds 50 Oe, only the ferrimagnetic transition can be observed. Above the transition temperature, the specific heat contains a significant magnetic contribution that is proportional to T 1/2. The calculation suggests that the nearest neighbor (NN) intra-chain antiferromagnetic exchange J 1 is much larger than the next nearest neighbor (NNN) intra-chain ferromagnetic exchange J 2. Therefore, Ba9V3Se15 can be regarded as an effective ferromagnetic chains with effective spin-1/2 by the formation of the V(2)(↓) V(1)(↑) V(2)(↓) cluster.

19.
Environ Sci Technol ; 50(18): 10179-86, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27562531

RESUMO

Selenate (SeO4(2-)) bioreduction is possible with oxidation of a range of organic or inorganic electron donors, but it never has been reported with methane gas (CH4) as the electron donor. In this study, we achieved complete SeO4(2-) bioreduction in a membrane biofilm reactor (MBfR) using CH4 as the sole added electron donor. The introduction of nitrate (NO3(-)) slightly inhibited SeO4(2-) reduction, but the two oxyanions were simultaneously reduced, even when the supply rate of CH4 was limited. The main SeO4(2-)-reduction product was nanospherical Se(0), which was identified by scanning electron microscopy coupled to energy dispersive X-ray analysis (SEM-EDS). Community analysis provided evidence for two mechanisms for SeO4(2-) bioreduction in the CH4-based MBfR: a single methanotrophic genus, such as Methylomonas, performed CH4 oxidation directly coupled to SeO4(2-) reduction, and a methanotroph oxidized CH4 to form organic metabolites that were electron donors for a synergistic SeO4(2-)-reducing bacterium.


Assuntos
Biofilmes , Metano/metabolismo , Reatores Biológicos , Oxirredução , Ácido Selênico
20.
Cytokine ; 86: 86-91, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27497158

RESUMO

BACKGROUND AND AIMS: The interleukin (IL)-10-production B cells play an important role in the pathogenesis of atherosclerosis (Asro) with unknown mechanism. Micro RNA (miR)-17-92 cluster has strong immune regulatory activities. This study tests a hypothesis that miR-17-92 cluster suppresses IL-10 expression in B cells of Asro patients. METHODS: Patients with Asro were recruited into this study. Peripheral blood samples were collected from the patients. B cells were isolated from the blood samples and analyzed to elucidate the role of miR-17-92 in the regulation of IL-10 expression. RESULTS: Peripheral B cells from patients with Asro show lower levels of IL-10 than that from healthy subjects. The IL-10 expression in the B cells is negatively correlated with the expression of miR-19a in the B cells. The serum levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ and interleukin (IL)-4 in Asro patients were higher than healthy subjects. Exposure to TNF-α or IFN-γ or IL-4 suppressed IL-10 expression in B cells via increasing the expression of miR-19a in B cells, which could be abolished by Inhibition of miR-19a. CONCLUSIONS: TNF-α or IFN-γ or IL-4 suppresses IL-10 in B cells via up regulating miR-19a expression.


Assuntos
Aterosclerose/imunologia , Linfócitos B/imunologia , Interleucina-10/antagonistas & inibidores , Interleucina-10/genética , MicroRNAs/genética , Interferência de RNA , Aterosclerose/sangue , Linfócitos B/efeitos dos fármacos , Feminino , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-10/imunologia , Interleucina-4/sangue , Masculino , MicroRNAs/imunologia , MicroRNAs/metabolismo , RNA Longo não Codificante , Reação em Cadeia da Polimerase em Tempo Real , Fator de Necrose Tumoral alfa/sangue
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