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1.
J Asthma Allergy ; 17: 633-651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006241

RESUMO

Allergic rhinitis is a chronic non-infectious inflammation of the nasal mucosa mediated by specific IgE. Recently, the human microbiome has drawn broad interest as a potential new target for treating this condition. This paper succinctly summarizes the main findings of 17 eligible studies published by February 2024, involving 1044 allergic rhinitis patients and 954 healthy controls from 5 countries. These studies examine differences in the human microbiome across important mucosal interfaces, including the nasal and intestinal areas, between patients and controls. Overall, findings suggest variations in the gut microbiota between allergic rhinitis patients and healthy individuals, although the specific bacterial taxa that significantly changed were not always consistent across studies. Due to the limited scope of existing research and patient coverage, the relationship between the nasal microbiome and allergic rhinitis remains inconclusive. The article discusses the potential immune-regulating role of the gut microbiome in allergic rhinitis. Further well-designed clinical trials with large-scale recruitment of allergic rhinitis patients are encouraged.

2.
Sci Rep ; 14(1): 14145, 2024 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898042

RESUMO

This study probes the utility of biomarkers for microsatellite instability (MSI) detection and elucidates the molecular dynamics propelling colorectal cancer (CRC) progression. We synthesized a primer panel targeting 725 MSI loci, informed by The Cancer Genome Atlas (TCGA) and ancillary databases, to construct an amplicon library for next-generation sequencing (NGS). K-means clustering facilitated the distillation of 8 prime MSI loci, including activin A receptor type 2A (ACVR2A). Subsequently, we explored ACVR2A's influence on CRC advancement through in vivo tumor experiments and hematoxylin-eosin (HE) staining. Transwell assays gauged ACVR2A's role in CRC cell migration and invasion, while colony formation assays appraised cell proliferation. Western blotting illuminated the impact of ACVR2A suppression on CRC's PI3K/AKT/mTOR pathway protein expressions under hypoxia. Additionally, ACVR2A's influence on CRC-induced angiogenesis was quantified via angiogenesis assays. K-means clustering of NGS data pinpointed 32 MSI loci specific to tumor and DNA mismatch repair deficiency (dMMR) tissues. ACVR2A emerged as a pivotal biomarker, discerning MSI-H tissues with 90.97% sensitivity. A curated 8-loci set demonstrated 100% sensitivity and specificity for MSI-H detection in CRC. In vitro analyses corroborated ACVR2A's critical role, revealing its suppression of CRC proliferation, migration, and invasion. Moreover, ACVR2A inhibition under CRC-induced hypoxia markedly escalated MMP3, CyclinA, CyclinD1, and HIF1α protein expressions, alongside angiogenesis, by triggering the PI3K/AKT/mTOR cascade. The 8-loci ensemble stands as the optimal marker for MSI-H identification in CRC. ACVR2A, a central element within this group, deters CRC progression, while its suppression amplifies PI3K/AKT/mTOR signaling and angiogenesis under hypoxic stress.


Assuntos
Receptores de Activinas Tipo II , Movimento Celular , Neoplasias Colorretais , Progressão da Doença , Instabilidade de Microssatélites , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Humanos , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/metabolismo , Animais , Movimento Celular/genética , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Transdução de Sinais , Masculino , Sequenciamento de Nucleotídeos em Larga Escala , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética
3.
Nanotechnology ; 35(29)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38588661

RESUMO

Cathodoluminescence and electron backscatter diffraction have been applied to exactly the same grain boundaries (GBs) in a Cu(In,Ga)S2solar absorber in order to investigate the influence of microstructure on the radiative recombination behaviour at the GBs. Two different types of GB with different microstructure were analysed in detail: random high angle grain boundaries (RHAGBs) and Σ3 GBs. We found that the radiative recombination at all RHAGBs was inhibited to some extent, whereas at Σ3 GBs three different observations were made: unchanged, hindered, or promoted radiative recombination. These distinct behaviours may be linked to atomic-scale grain boundary structural differences. The majority of GBs also exhibited a small spectral shift of about ±10 meV relative to the local grain interior (GI) and a few of them showed spectral shifts of up to ±40 meV. Red and blue shifts were observed with roughly equal frequency.

4.
Small Methods ; : e2301385, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38415955

RESUMO

Sugar substitutes are popular due to their akin taste and low calories. However, excessive use of aspartame and erythritol can have varying effects. While D-allulose is presently deemed a secure alternative to sugar, its excessive consumption is not devoid of cellular stress implications. In this study, the evolution of Escherichia coli Nissle 1917 (EcN) is directed to utilize allulose as sole carbon source through a combination of adaptive laboratory evolution (ALE) and fluorescence-activated droplet sorting (FADS) techniques. Employing whole genome sequencing (WGS) and clustered regularly interspaced short palindromic repeats interference (CRISPRi) in conjunction with compensatory expression displayed those genetic mutations in sugar and amino acid metabolic pathways, including glnP, glpF, gmpA, nagE, pgmB, ybaN, etc., increased allulose assimilation. Enzyme-substrate dynamics simulations and deep learning predict enhanced substrate specificity and catalytic efficiency in nagE A247E and pgmB G12R mutants. The findings evince that these mutations hold considerable promise in enhancing allulose uptake and facilitating its conversion into glycolysis, thus signifying the emergence of a novel metabolic pathway for allulose utilization. These revelations bear immense potential for the sustainable utilization of D-allulose in promoting health and well-being.

5.
Sci Total Environ ; 918: 170577, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38311074

RESUMO

Soil contamination with heavy metals has emerged as a global environmental threat, compromising agricultural productivity, ecosystem integrity, and human health. Conventional remediation techniques often fall short due to high costs, operational complexities, and environmental drawbacks. Plant-based disposal technologies, including biochar, phytometallurgy, and phrolysis, have emerged as promising solutions in this regard. Grounded in a novel experimental framework, biochar is studied for its dual role as soil amendment and metal adsorbent, while phytometallurgy is explored for its potential in resource recovery and economic benefits derived from harvested metal-rich plant biomass. Pyrolysis, in turn, is assessed for transforming contaminated biomass into value-added products, thereby minimizing waste. These plant disposal technologies create a circular model of remediation and resource utilization that holds the potential for application in large-scale soil recovery projects, development of environmentally friendly agro-industries, and advancement in sustainable waste management practices. This review mainly discussed cutting-edge plant disposal technologies-biochar application, phytometallurgy, and pyrolysis-as revolutionary approaches to soil heavy metal remediation. The efficacy, cost-effectiveness, and environmental impact of these innovative technologies are especially evaluated in comparison with traditional methods. The success of these applications could signal a paradigm shift in how we approach both environmental remediation and resource recovery, with profound implications for sustainable development and circular economy strategies.


Assuntos
Recuperação e Remediação Ambiental , Metais Pesados , Poluentes do Solo , Humanos , Solo , Ecossistema , Poluentes do Solo/análise , Metais Pesados/análise , Carvão Vegetal , Plantas , Tecnologia
6.
J Vis Exp ; (199)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37811950

RESUMO

Allergic rhinitis (AR) is a chronic, non-infectious inflammatory disease of the nasal mucosa, primarily mediated by specific immunoglobulin E (IgE), affecting approximately 10%-20% of the world's population. While immunofluorescence (IF) staining has long been a standard technique for detecting disease-specific protein expression, conventional IF techniques are limited in their ability to detect the expression levels of three or more proteins in the same sample. Consequently, multicolor IF techniques have been developed in recent years, which allow the simultaneous labeling of multiple targets in cells or tissues. This protocol provides a comprehensive overview of the process for establishing a rat model of AR, obtaining nasal mucosal samples, and the technical procedures for multicolor immunofluorescence. All rats in the AR group exhibited typical symptoms such as sneezing, a runny nose, and an itchy nose, with behavioral observations scoring ≥5 points. Hematoxylin and eosin (H&E) staining revealed increased inflammatory cell counts and disrupted nasal mucosal integrity in the AR group. Multicolor immunofluorescence (mIF) demonstrated increased expression of RORγt and TICAM-1, while Foxp3 expression decreased in the nasal mucosa tissue of AR rats.


Assuntos
Rinite Alérgica , Ratos , Animais , Mucosa Nasal , Imunoglobulina E , Corantes , Modelos Animais de Doenças , Ovalbumina
7.
ACS Appl Mater Interfaces ; 15(40): 46861-46871, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769166

RESUMO

GeSe photovoltaic thin films are very promising for photoelectrochemical (PEC) hydrogen evolution. The GeSe-based PEC water splitting device is a system containing a photoelectrode, electrolyte, and other packages, and the performance of the GeSe photoelectrode inside the system is very sensitive to the PEC system environment, such as the electrolyte temperature, pH, and concentration. Here, we reveal how the electrolyte environment at the electrolyte/photoelectrode interface influences the optoelectronic/PEC properties of GeSe photoelectrodes. It was found that the photocurrent density of the GeSe photoelectrode increased with temperature between 10 and 50 °C but decreased when the temperature was over 50 °C. In addition, the pH values of the electrolyte were inversely proportional to the photocurrent density of the GeSe photoelectrode. Moreover, the PEC performance improved as the sodium ion concentration of the electrolyte increased. The results in this work should provide a new direction for further optimizing the performance of photoelectrodes.

8.
Front Cardiovasc Med ; 10: 1132062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456820

RESUMO

Background: We aimed to evaluate the efficacy and safety of the 'jailed semi-inflated balloon technique' (JSIBT) for side branch (SB) protection in STEMI patients with a culprit lesion involving a coronary artery bifurcation while undergoing emergent percutaneous coronary intervention (PCI). Methods: We treated between Jan, 2011 and Jun, 2020, a total of 264 STEMI patients with a culprit lesion that involved a coronary artery bifurcation using primary PCI. In 30 patients, SB was protected by JSIBT (the JSIBT group). In 234 patients, SB was either protected or not protected by a placed wire (the non-JSIBT group). Results: In both groups, after PCI procedure, TIMI flows of main vessel (MV) and SB were increased significantly compared with their measurements before the procedure. TIMI flows of post-procedural MV were similar between the two groups. In the JSIBT group, TIMI flows of SB both peri-procedure and post-procedure measurements were significantly greater than the non-JSIBT group. Despite a higher incidence of SB dissection in the JSIBT group, no inter-group difference was found in their total SB complications (like SB dissection, SB occlusion, wire entrapment or balloon rupture/entrapment). While JSIBT was an independent predictor for the SB TIMI 3 flow measured at the end of primary PCI, it was not an independent predictor for SB complications. Conclusion: The use of JSIBT as a method of SB protection during primary PCI not only provided better SB protection, but it also had a similar rate of SB complications compared with those with or without prior application of SB wire. This technique may be an effective method of protecting SB for STEMI patients involving coronary artery bifurcation and underwent emergent PCI.

9.
J Environ Sci (China) ; 129: 1-15, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36804226

RESUMO

Due to the combined effect of sluices and sea tide, the sluice-controlled coastal plain river would be characterized by both trophic state and salinity gradients, affecting the spatiotemporal optical properties of dissolved organic matter (DOM). In this study, we investigated the spatiotemporal variation of water quality parameters and optical properties of DOM in the Haihe River, a representative sluice-controlled coastal plain river in Tianjin, China. A significant salinity gradient and four trophic states were observed in the water body of the Haihe River. Two humic- and one protein-like substances were identified from the DOM by the three-dimensional fluorescence spectra combined with the parallel factor (PARAFAC) analysis. Pearson's correlation analysis and redundancy analysis (RDA) showed that the salinity significantly affected the abundance of chromophoric DOM (CDOM) but did not cause significant changes in the fluorescence optical characteristics. In addition, the effect of Trophic state index (TSI) on the CDOM abundance was greater than that on the fluorescence intensity of fluorescent dissolved organic matter (FDOM). In the water body with both salinity and trophic state gradients, TSI posed a greater influence than salinity on the CDOM abundance. Our results fill the research gap in spatiotemporal DOM characteristics and water quality variation in water bodies with both salinity and trophic state gradients. These results are beneficial for clarifying the joint influence of saline intrusion and sluices on the DOM characteristics and water quality in sluice-controlled coastal plain rivers.


Assuntos
Matéria Orgânica Dissolvida , Rios , Salinidade , Qualidade da Água , China , Espectrometria de Fluorescência
10.
Adv Wound Care (New Rochelle) ; 12(1): 1-14, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35081741

RESUMO

Objective: Although the use of dexamethasone as an adjunct agent is associated with alleviating pain and prolonging analgesic duration in local wound infiltration (LWI), efficacy and safety of dexamethasone infiltration have not been fully explored. The study sought to quantify the pooled effects of dexamethasone infiltration on postoperative pain, analgesic consumption, and side effects through a review of randomized controlled trials (RCTs). Approach: RCTs comparing dexamethasone + LWI with LWI alone were retrieved from seven electronic databases. Co-primary outcomes were rest pain scores and cumulative morphine equivalent consumption within 24 h postoperatively. The study followed PRISMA, AMSTAR, and the Cochrane Collaboration. Results: Eight trials comprising 609 patients were included in the final analysis. Results indicated that dexamethasone infiltration effects were only statistical but not clinically significant at individual time points of rest pain and patient satisfaction scores. Notably, the effect of dexamethasone infiltration therapy on other pain-related parameters, including cumulative morphine consumption (mean difference, -9.05 mg; 95% CI: -22.47 to 4.37), was not significantly different compared with the control group. Analysis showed no significant differences in safety indicators between the two groups. The overall quality of evidence was high to very low. Innovation: Although statistically significant effects of dexamethasone infiltration were observed for some outcomes of postoperative wound pain, the overall benefits were below the expected minimal clinically important difference. Conclusions: In summary, the current evidence does not support routine clinical use of dexamethasone in LWI. However, further studies should explore the clinical value of preemptive analgesia and safety of a combination of dexamethasone with ropivacaine for LWI.


Assuntos
Analgesia , Dor Pós-Operatória , Humanos , Ropivacaina/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Morfina/farmacologia , Morfina/uso terapêutico , Analgesia/métodos , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Adv Sci (Weinh) ; 10(5): e2205726, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36538733

RESUMO

A process accumulated record solar to hydrogen (STH) conversion efficiency of 8% is achieved on the Cu2 ZnSnS4 -BiVO4 tandem cell by the synergistic coupling effect of solar thermal and photoelectrochemical (PEC) water splitting with the dynamic balance of solar energy storage and conversion of the greenhouse system. This is the first report of a Cu2 ZnSnS4 -BiVO4 tandem cell with a high unbiased STH efficiency of over 8% for solar water splitting due to the greenhouse device system. The greenhouse acts as a solar thermal energy storage cell, which absorbs infrared solar light and storage as thermal energy with the solar light illumination time, while thermoelectric device (TD) converts thermal energy into electric power, electric power is also recycled and added onto Cu2 ZnSnS4 -BiVO4 tandem cell for enhanced overall water splitting. Finally, the solar water splitting properties of the TD-Cu2 ZnSnS4 -BiVO4 integrated tandem cell in pure natural seawater are demonstrated, and a champion STH efficiency of 2.46% is presented, while a large area (25 cm2 ) TD-Cu2 ZnSnS4 -BiVO4 integrated tandem device with superior long-term stability is investigated for 1 week, which provides new insight into photoelectrochemical solar water splitting devices.

12.
Adv Sci (Weinh) ; 9(33): e2204029, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36253117

RESUMO

The ternary compound photovoltaic semiconductor Cu3 BiS3 thin film-based photoelectrode demonstrates a quite promising potential for photoelectrochemical hydrogen evolution. The presented high onset potential of 0.9 VRHE attracts much attention and shows that the Cu3 BiS3 thin films are quite good as an efficient solar water splitting photoelectrode. However, the CdS buffer does not fit the Cu3 BiS3 thin film: the conduction band offset between CdS and Cu3 BiS3 reaches 0.7 eV, and such a high conduction band offset (CBO) significantly increases the interfacial recombination ratio and is the main reason for the relatively low photocurrent of the Cu3 BiS3 /CdS photoelectrode. In this study, the Inx Cd1- x S buffer layer is found to be significantly lowered the CBO of CBS/buffer and that the In incorporation ratio of the buffer influences the CBO value of the CBS/buffer. The Pt-TiO2 /In0.6 Cd0.4 S/Cu3 BiS3 photocathode exhibits an appreciable photocurrent density of ≈12.20 mA cm-2 at 0 VRHE with onset potential of more than 0.9 VRHE , and the ABPE of the Cu3 BiS3 -based photocathode reaches the highest value of 3.13%. By application of the In0.6 Cd0.4 S buffer, the Cu3 BiS3 -BiVO4 tandem cell presents a stable and excellent unbiased STH of 2.57% for over 100 h.

13.
Cell Prolif ; 55(4): e13211, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35274784

RESUMO

OBJECTIVES: Short telomeres in alveolar type 2 (AT2) cells have been associated with many lung diseases. The study aimed to investigate the regeneration capacity of AT2 cells with short telomeres by knocking out Tert in mice (G4 Tert-/- ) from the whole to the cellular level. MATERIALS AND METHODS: The lung injury model of mice was established by left pneumonectomy (PNX). The proliferation and differentiation of AT2 cells were observed by immunofluorescence staining in vivo and in vitro. The difference of the gene expression between control and G4 Tert-/- group during the regeneration of AT2 cells was compared by RNA sequencing. The expression of tubulin polymerization promoting protein 3 (TPPP3) was reduced by adeno-associated virus delivery. RESULTS: The alveolar regeneration in G4 Tert-/- mice was impaired after PNX-induced lung injury. The regulation of cytoskeleton remodelling was defective in G4 Tert-/- AT2 cells. The expression of TPPP3 was gradually increased during AT2 cell differentiation. The expression level of TPPP3 was reduced in G4 Tert-/- AT2 cells. Reducing TPPP3 expression in AT2 cells limits the microtubule remodelling and differentiation of AT2 cells. CONCLUSION: Short telomeres in AT2 cells result in the reduced expression level of TPPP3, leading to impaired regeneration capacity of AT2 cells.


Assuntos
Lesão Pulmonar , Células Epiteliais Alveolares/metabolismo , Animais , Diferenciação Celular/fisiologia , Lesão Pulmonar/metabolismo , Camundongos , Telômero/genética , Encurtamento do Telômero
14.
J Phys Chem A ; 126(3): 365-372, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35023736

RESUMO

Dimerizations of fulvene metal tricarbonyl complexes of the type (C5H4CRR')M(CO)3 (R, R' = MeO, Me, H; M = Cr, Mo, W) to form a metal-metal bond and a new carbon-carbon bond, thereby giving binuclear cyclopentadienyl metal carbonyl derivatives, are predicted to be thermochemically favored but to have significant activation energies ranging from ΔE = 19 to 42 kcal/mol. However, the introduction of dimethylamino but not methoxy substituents onto the exocyclic carbon atom changes the situation drastically so that the monomers [C5H4CH(NMe2)]M(CO)3 and [C5H4C(NMe2)2]M(CO)3 become strongly thermochemically favored, lying ΔE = 43 kcal/mol (M = W) to 63 kcal/mol (M = Cr) below their corresponding dimers. In such dimethylamino-substituted (fulvene)M(CO)3 derivatives, the M-C distance to the exocyclic fulvene carbon is lengthened beyond the bonding distance to give a zwitterionic structure with a pentahapto fulvene ligand. Such M-C distances in (fulvene)M(CO)3 complexes, which have preferred zwitterionic structures, increase with increasing solvent polarity (i.e., dielectric constant) until a saturation point is reached.

15.
Nature ; 601(7891): 118-124, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34912121

RESUMO

The skin serves as a physical barrier and an immunological interface that protects the body from the external environment1-3. Aberrant activation of immune cells can induce common skin autoimmune diseases such as vitiligo, which are often characterized by bilateral symmetric lesions in certain anatomic regions of the body4-6. Understanding what orchestrates the activities of cutaneous immune cells at an organ level is necessary for the treatment of autoimmune diseases. Here we identify subsets of dermal fibroblasts that are responsible for driving patterned autoimmune activity, by using a robust mouse model of vitiligo that is based on the activation of endogenous auto-reactive CD8+ T cells that target epidermal melanocytes. Using a combination of single-cell analysis of skin samples from patients with vitiligo, cell-type-specific genetic knockouts and engraftment experiments, we find that among multiple interferon-γ (IFNγ)-responsive cell types in vitiligo-affected skin, dermal fibroblasts are uniquely required to recruit and activate CD8+ cytotoxic T cells through secreted chemokines. Anatomically distinct human dermal fibroblasts exhibit intrinsic differences in the expression of chemokines in response to IFNγ. In mouse models of vitiligo, regional IFNγ-resistant fibroblasts determine the autoimmune pattern of depigmentation in the skin. Our study identifies anatomically distinct fibroblasts with permissive or repressive IFNγ responses as the key determinant of body-level patterns of lesions in vitiligo, and highlights mesenchymal subpopulations as therapeutic targets for treating autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Fibroblastos/imunologia , Pele/imunologia , Pele/patologia , Vitiligo/imunologia , Vitiligo/patologia , Adolescente , Adulto , Animais , Linfócitos T CD8-Positivos/imunologia , Quimiocina CXCL10/imunologia , Quimiocina CXCL9/imunologia , Criança , Modelos Animais de Doenças , Feminino , Fibroblastos/patologia , Humanos , Interferon gama/imunologia , Masculino , Melanócitos/imunologia , Melanócitos/patologia , Camundongos , Pessoa de Meia-Idade , Comunicação Parácrina , RNA-Seq , Análise de Célula Única , Células Estromais/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto Jovem
16.
Carbohydr Polym ; 274: 118630, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34702454

RESUMO

Cellulosic substrates completely originating from biomass have gained increasing attention for utilization in photoelectric devices due to their biodegradability, sustainability, and renewability. Herein, a simple one-step strategy was used to fabricate transparent (84.2%-90% at 550 nm) all-cellulose composites (ACCs) with customized optical haze (14.7%-83.7% at 550 nm) from wood and bamboo pulp due to their variable solubility. Surface roughness, coagulation bath composition, and the size of the undissolved cellulose fibers contributed to optical haze regulation. Fabricated ACCs demonstrated water resistance, thermal stability, and good mechanical properties. Moreover, an enhancement in the power conversion efficiency of a perovskite solar cell was achieved by simple attachment. Compared with non-sustainable petroleum base materials, ACCs exhibit biodegradability and renewability, which makes the composites promising in large-scale production and various applications due to their tunable haze.

17.
J Phys Chem Lett ; 12(28): 6486-6491, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34240874

RESUMO

In 2019, Diaz-Urrutia and Ott developed a high-yield method for direct conversion of methane to methanesulfonic acid and proposed a cationic chain reaction mechanism. However, Roytman and Singleton questioned this mechanism, and they favored a free-radical mechanism. In the present paper, we studied both the cationic chain and radical mechanisms and found the radical mechanism is more favorable, since it has a much lower energy barrier. However, the radical mechanism has not considered the effect of ions for the reaction taking place in oleum. Thus, we studied a simple model of a protonated radical mechanism, which further lowers the energy barrier. Although the true mechanism for the CH4 + SO3 reaction could be more complicated in electrolyte solutions, this model should be helpful for the further study of the mechanism of this reaction.

18.
J Environ Sci (China) ; 104: 40-52, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33985743

RESUMO

The Yongding New River is essential for the water supplies of Tianjin. To date, there is no comprehensive report that assesses the year-round water quality of the Yongding New River Main stream. Moreover, little attention has been given to determining a combined weight for improving the traditional comprehensive water quality identification index (ICWQII) by the game theory. Seven water quality parameters were investigated monthly along the main stream of the Yongding New River from May 2018 to April 2019. Organic contaminants and nitrogen pollution were mainly caused by point sources pollution, and the total phosphorus mainly by non-point source pollution. Dramatic spatio-temporal variations of water quality parameters were jointly caused by different pollutant sources and hydrometeorological factors. In terms of this study, an improved comprehensive water quality identification index (ICWQII) based on entropy weight or variation coefficient and traditional CWQII underestimated the water qualities, and an ICWQII based on the superstandard multiple method overvalued the assessments. By contrast, water qualities assessments done with an ICWQII based on the game theory matched perfectly with the practical situation. The ICWQII based on game theory proposed in this study takes into account not only the degree of disorder and variation of water quality data, but also the influence of standard-exceeded pollution indicators, whose results are relatively reasonable. All findings and the ICWQII based on game theory can provide scientific support for decisions related to the water environment management of the Yongding New River and other waters.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , China , Monitoramento Ambiental , Teoria dos Jogos , Nitrogênio/análise , Fósforo/análise , Rios , Poluentes Químicos da Água/análise , Poluição da Água/análise
19.
Pathogens ; 10(4)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917709

RESUMO

Arthrobacter woluwensis is a Gram-positive, aerobic Actinobacteria that is widely distributed in the environment worldwide. Little is known about A. woluwensis infection and it is commonly mis-identified by culturing with commercial kits. To date, only six cases of bacteremia caused by A. woluwensis have been reported in the literature. Herein, we report a case of Arthrobacter woluwensis bacteremia in an immunocompromised host. In this case report, the results of antimicrobial susceptibility testing showed that this clinical isolate of A. woluwensis is sensitive to vancomycin, teicoplanin, but resistant to penicillin, cephalosporin and ciprofloxacin. Additionally, whole genome sequencing analysis identified common subunits of the urease system.

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