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1.
Langmuir ; 40(19): 10346-10354, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38695309

RESUMO

To fully exploit pore engineering in the design of more efficient zeolite adsorbents for volatile organic compound (VOC) treatment, the roles of meso- and micropores need to be clarified to provide the theoretical basis and feasible measures. In this work, the three VOC sorption properties of conventional and hierarchical porous beta zeolites were comparatively investigated to study the roles of meso- and micropores. There is a division of functions between micro- and mesopores, with micropores being the main VOC adsorption sites and mesopores greatly enhancing VOC diffusion and adsorbent reusability. On the one hand, micropores should be preserved as much as possible because obtaining mesopores by sacrificing micropores (i.e., alkali treatment) results in 28-60% decreases in adsorption capacities. On the other hand, mesopore introduction is highly desirable, which results in an enhancement of VOC intraparticle diffusion rates by 1.3-2.3 times (at the VOC concentration of 600 ppm) and chlorobenzene adsorption capacity on the 20th cycle increasing from 78% of the initial value to 89 and 93%. The findings may provide valuable information about zeolite-based adsorbents for adsorption removal or recovery of VOCs.

2.
Faraday Discuss ; 248(0): 89-101, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-37753847

RESUMO

The reaction mechanism underpinning the operation of K-O2 batteries, particularly the O2 reactions at the positive electrode, is still not completely understood. In this work, by combining in situ Raman spectroelectrochemistry and density functional theory calculations, we report on a fundamental study of K-O2 electrochemistry at a model interface of Au electrode/DMSO electrolyte. The key products and intermediates (O2-, KO2 and K2O2) are identified and their dependency on the electrode potential is revealed. At high potentials, the first reduction intermediate of O2-* radical anions (* denotes the adsorbed state) can desorb from the Au electrode surface and combine with K+ cations in the electrolyte producing KO2via a solution-mediated pathway. At low potentials, O2 can be directly reduced to on the Au electrode surface, which can be further reduced to at extremely low potentials. The fact that K2O2 has only been detected in the very high overpotential regime indicates a lack of KO2 disproportionation reaction both on the Au electrode surface and in the electrolyte solution. This work addresses the fundamental mechanism and origin of the high reversibility of the aprotic K-O2 batteries.

3.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1818-1825, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812194

RESUMO

A label-free fluorescence method based on malachite green/aptamer was developed for the detection of ochratoxin A(OTA) in traditional Chinese medicines. Malachite green itself exhibits weak fluorescence. Upon interaction with the aptamer specific to OTA, the G-quadruplex structure of the aptamer provides a protective microenvironment for malachite green, which significantly enhances its fluorescence signal. After OTA is added, preferential binding occurs between the aptamer and OTA, and malachite green will be released from the aptamer, which weakens the fluorescence signal. According to this principle, this paper established a fluorescence method with the aptamer of OTA as the recognition element and malachite green as the fluorescent probe for the detection of OTA in traditional Chinese medicines. The key experimental factors such as the concentrations of metal ions, aptamer, and malachite green were optimized to improve the performance of the method. OTA was detected under the optimal experimental conditions, and the results showed that with the increase in OTA concentration, the fluorescence signal gradually weakened. Within the range of 20-1 000 nmol·L~(-1), the OTA concentration was linearly correlated with the fluorescence signal ratio ΔF/F(ΔF=F_0-F, where F_0 is the fluorescence signal of aptamer/malachite green, and F is the fluorescence signal of OTA/aptamer/malachite green), with R~2 of 0.995. The limit of detection of the established method was 7.1 nmol·L~(-1). Furthermore, three substances structurally similar to OTA and two mycotoxins that may coexist with OTA were selected for experiments, which aimed to examine the cross-reactivity and specificity of the established method. The cross-reactivity experiments demonstrated that the interferers did not significantly affect the fluorescence signal of the detection system. The specificity experiments revealed that when mycotoxins were mixed with OTA, the fluorescence signal generated by the mixture closely resembled that of OTA itself. The results indicated that even in the presence of interferents, the established method remained unaffected and demonstrated excellent specificity. Additionally, this method exhibited remarkable reproducibility and stability. In the case of simple centrifugation and dilution of traditional Chinese medicine samples(Puerariae Lobatae Radix, Sophorae Flavescentis Radix, and Periplocae Cortex), the OTA detection method was applicable, with recovery rates ranging from 91.5% to 121.3%. Notably, this approach does not need complex pretreatment of traditional Chinese medicines while offering simple operation, low detection costs, and short detection time. Furthermore, by incorporating aptamers into the quality evaluation of traditional Chinese medicines, this method expands the application scope of aptamers.


Assuntos
Aptâmeros de Nucleotídeos , Medicamentos de Ervas Chinesas , Ocratoxinas , Corantes de Rosanilina , Corantes de Rosanilina/química , Corantes de Rosanilina/análise , Ocratoxinas/análise , Ocratoxinas/química , Aptâmeros de Nucleotídeos/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Espectrometria de Fluorescência/métodos , Contaminação de Medicamentos/prevenção & controle , Fluorescência , Medicina Tradicional Chinesa
4.
Planta ; 257(5): 85, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36944703

RESUMO

MAIN CONCLUSION: PPO was purified from Cistanche deserticola, and its enzymatic characteristics were clarified. It was found that microwave treatment was an efficient way to inactivate PPO. Polyphenol oxidase (PPO) from Cistanche deserticola was obtained and purified through an acetone precipitation and anion exchange column, the enzymatic characteristics and inactivation kinetics of PPO were studied. The specific activity of PPO was 73135.15 ± 6625.7 U/mg after purification, the purification multiple was 48.91 ± 4.43 times, and the recovery was 30.96 ± 0.27%. The molecular weight of the PPO component is about 66 kDa by SDS-PAGE analysis. The optimum substrate of PPO was catechol (Vmax = 0.048 U/mL, Km = 21.70 mM) and the optimum temperature and pH were 30 °C and 7, respectively. When the temperature is above 50 °C, pH < 3 or pH > 10, the enzyme activity can be significantly inhibited. The first-order kinetic fitting shows that microwave inactivation has lesser k values, larger D values and shorter t1/2. It was found that microwave treatment is considered as an efficient and feasible way to inactive PPO by comparing the Z values and Ea values of the two thermal treatments.


Assuntos
Cistanche , Cistanche/metabolismo , Catecol Oxidase/química , Catecol Oxidase/metabolismo , Cinética , Temperatura , Peso Molecular , Concentração de Íons de Hidrogênio
5.
Environ Sci Technol ; 57(48): 20043-20052, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37992316

RESUMO

Levoglucosan (LG) is a pyrolysis product of cellulose and hemicellulose at low combustion temperatures. However, LG release cannot be determined only by considering the contents of cellulose and hemicellulose exclusively due to the complexity of combustion processes and the physical-chemical properties of the fuel. This study detected the emission factors (EFs) of LG from 22 different solid fuel samples (including coal and biomass) by considering 18 different fuel properties and five combustion parameters. The average LGEFs during solid fuel burning varied in a range of 0.03-136 mg kg-1, with a magnitude difference of 1-4 orders. While the variations in cellulose (59.5-368 mg g-1) and hemicellulose (73.5-165 mg g-1) contents of fuel samples were only one- to 6-fold. A short combustion duration (<150 min) and a medium combustion temperature (200-400 °C) influenced by volatile and ash contents are crucial for the generation and accumulation of LG. A random forest coupled with the Akaike information criterion stepwise regression model successfully explained 96% of the total LG emission variation using three variables (ash content, cellulose content, and modified combustion efficiency). The ash content promoted coke formation and LG chain cracking by increasing the pyrolysis temperature and is considered the most important factor. The alkali metal in ash can reduce the energy barrier of intramolecular ring contraction reactions and inhibit the dehydration reactions, which led to additional heat being utilized by the competitive pathways of LG formation. This study provided a method to address the parametrization and release mechanisms of combustion source emissions.


Assuntos
Poluentes Atmosféricos , Carvão Mineral , Carvão Mineral/análise , Glucose , Temperatura , Celulose , Poluentes Atmosféricos/análise
6.
J Chem Phys ; 158(17)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37125721

RESUMO

A wide spectrum of state-of-the-art characterization techniques have been devised to monitor the electrode-electrolyte interface that dictates the performance of electrochemical devices. However, coupling multiple characterization techniques to realize in situ multidimensional analysis of electrochemical interfaces remains a challenge. Herein, we presented a hyphenated differential electrochemical mass spectrometry and attenuated total reflection surface enhanced infrared absorption spectroscopy analytical method via a specially designed electrochemical cell that enables a simultaneous detection of deposited and volatile interface species under electrochemical reaction conditions, especially suitable for non-aqueous, electrolyte-based energy devices. As a proof of concept, we demonstrated the capability of the homemade setup and obtained the valuable reaction mechanisms, by taking the tantalizing reactions in non-aqueous lithium-ion batteries (i.e., oxidation and reduction processes of carbonate-based electrolytes on Li1+xNi0.8Mn0.1Co0.1O2 and graphite surfaces) and lithium-oxygen batteries (i.e., reversibility of the oxygen reaction) as model reactions. Overall, we believe that the coupled and complementary techniques reported here will provide important insights into the interfacial electrochemistry of energy storage materials (i.e., in situ, multi-dimensional information in one single experiment) and generate much interest in the electrochemistry community and beyond.

7.
Spinal Cord ; 61(8): 422-429, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37402893

RESUMO

STUDY DESIGN: Animal experimental study. OBJECTIVES: Spinal cord injury (SCI) at or above the T6 level causes cardiovascular dysfunction. Maintaining cAMP levels with cAMP analogs can facilitate neurological recovery. In the present study, the effects of meglumine cyclic adenylate (MCA), a cAMP analog and approved cardiovascular drug, on cardiovascular and neurological recovery in acute T4-SCI in rats were investigated. SETTING: Hospital in Kunming, China. METHODS: Eighty rats were randomly allocated to five groups, and groups A-D received SCI: (A) a group administered MCA at 2 mg/kg/d iv qd, (B) a group administered dopamine at 2.5 to 5 µg/kg/min iv to maintain mean arterial pressure above 85 mm Hg, (C) a group administered atropine at 1 mg/kg iv bid, (D) a group receiving an equal volume of saline iv qd for 3 weeks after SCI and (E) a group undergoing laminectomy only. The cardiovascular and behavioral parameters of the rats were examined, and spinal cord tissues were processed for hematoxylin and eosin staining, Nissl staining, electron microscopy, and analysis of cAMP levels. RESULTS: Compared with dopamine or atropine, MCA significantly reversed the decrease in cAMP levels in both myocardial cells and the injured spinal cord; improved hypotension, bradycardia and behavioral parameters at 6 weeks; and improved spinal cord blood flow and histological structure at 7 days post-SCI. The regression analysis suggested spinal cord motor-function improved as decreased heart rate and mean arterial pressure were stopped post-SCI. CONCLUSIONS: MCA may be an effective treatment for acute SCI by sustaining cAMP-dependent reparative processes and improving post-SCI cardiovascular dysfunction. SPONSORSHIP: N/A.


Assuntos
Traumatismos da Medula Espinal , Ratos , Animais , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Dopamina/farmacologia , Dopamina/uso terapêutico , Medula Espinal/patologia , Hemodinâmica , Derivados da Atropina/farmacologia , Derivados da Atropina/uso terapêutico , Recuperação de Função Fisiológica , Modelos Animais de Doenças
8.
BMC Nurs ; 22(1): 146, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118749

RESUMO

BACKGROUND: Despite the increasing survival rates, liver transplant patients experience numerous postoperative complications and encounter significant challenges in long-term self-management. This study aims to examine the effectiveness of empowerment education in enhancing self-management skills and self-efficacy among liver transplant recipients. METHODS: A randomized, single-blind, single-center trial was conducted in China between August 2019 and September 2020, involving liver transplant recipients. The intervention group received 12 weeks of empowerment education, while the control group received 12 weeks of routine education. .The study assessed the patients' self-management and self-efficacy using the Liver Transplant Recipient Self-Management Questionnaire and the Self-efficacy for Managing Chronic Disease 6-Item Scale. Follow-up assessments were conducted at 1, 3, and 6 months after the intervention. RESULTS: Eighty-four patients were initially randomized to either the intervention group (n1 = 42) or the routine education group (n2 = 42). Twelve patients were excluded from the analysis due to loss of follow-up or discontinuation of the intervention, leaving 72 patients (n1 = 35, n2 = 37) for the final analysis. The scores for exercise and lifestyle management were significantly higher in the intervention group than in the control group at 1, 3, and 6 months after the intervention (t = 3.047, 5.875, 8.356, and t = 5.759, 4.681, 11.759, respectively; P < 0.05). At 3 and 6 months after the intervention, the scores for cognitive symptom management, communication with physicians, and self-efficacy were significantly higher in the intervention group than in the control group (t = 5.609, 6.416, and t = 5.576, 11.601, and t = 6.867, 15.071, respectively; P < 0.001). Within the intervention group, self-management scores increased significantly over time, while within the control group, the scores for communication with physicians, lifestyle, and self-efficacy showed a significant decline from 3 to 6 months after routine health education. CONCLUSIONS: The results of this study suggest that empowerment education is an effective means of improving the self-management and self-efficacy of liver transplant patients, with better outcomes compared to routine health education. These findings have important implications for nursing practice and provide valuable guidance for clinical education of liver transplant patients. TRIAL REGISTRATION: ChiCTR2200061561.

9.
J Bone Miner Metab ; 40(1): 66-80, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34778905

RESUMO

INTRODUCTION: Human umbilical cord blood-derived MSCs (hUC-MSCs) have the potential to differentiate into osteoblasts. This study investigated the function and potential mechanisms of a novel lncRNA LINC02381 in hUC-MSC osteogenic differentiation. MATERIALS AND METHODS: hUC-MSCs were maintained in osteogenic differentiation medium. RT-qPCR assay was performed to assess LINC02381 expression. Alizarin Red S (ARS) and alkaline phosphatase (ALP) staining were performed to evaluate osteogenic differentiation. The interaction between miR-21 and LINC0238/KLF12 was determined by luciferase reporter and RNA immunoprecipitation (RIP) assays. Chromatin immunoprecipitation (ChIP) assay was used to confirm the transcriptional regulation of KLF12 on Wnt4 promoter. The nuclear translocation of ß-catenin was evaluated using immunofluorescence. hUC-MSCs seeded on Bio-Oss Collagen scaffolds were transplanted into nude mice to assess in vivo osteogenesis. Bone formation was observed by H&E and Masson's trichrome staining. OSX and OPN levels were assessed by immunohistochemistry. RESULTS: LINC02381 was up-regulated in the clinical samples of osteoporotic patients. However, LINC02381 expression was reduced during osteogenic differentiation of hUC-MSCs. Enforced expression of LINC02381 suppressed the osteogenic differentiation of hUC-MSCs. Mechanistically, LINC02381 sponged miR-21 to enhance KLF12 expression, which led to the inactivation of Wnt/ß-catenin signaling pathway. Furthermore, miR-21 mimics or KLF12 silencing counteracted LINC02381-induced inhibition of osteogenic differentiation, whereas IWP-4 (an inhibitor of Wnt pathway) abolished this effect. CONCLUSION: In summary, LINC02381 repressed osteogenic differentiation of hUS-MSCs through sponging miR-21 to enhance KLF12-mediated inactivation of Wnt/ß-catenin pathway, indicating that LINC02381 might be a therapeutic target for osteoporosis.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Osteogênese , RNA Longo não Codificante/genética , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Camundongos Nus , MicroRNAs/genética , Osteogênese/genética , Via de Sinalização Wnt/genética , Proteína Wnt4
10.
Molecules ; 27(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35408704

RESUMO

Safflower seed oil (SSO) is considered to be an excellent edible oil since it contains abundant essential unsaturated fatty acids and lipid concomitants. However, the traditional alkali-refined deacidification process of SSO results in a serious loss of bioactive components of the oil and also yields massive amounts of wastewater. In this study, SSO was first extracted by ultrasonic-assisted ethanol extraction (UAEE), and the extraction process was optimized using random centroid optimization. By exploring the effects of ethanol concentration, solid−liquid ratio, ultrasonic time, and the number of deacidification times, the optimum conditions for the deacidification of safflower seed oil were obtained as follows: ethanol concentration 100%, solid−liquid ratio 1:4, ultrasonic time 29 min, and number of deacidification cycles (×2). The deacidification rate was 97.13% ± 0.70%, better than alkali-refining (72.16% ± 0.13%). The values of acid, peroxide, anisidine and total oxidation of UAEE-deacidified SSO were significantly lower than those of alkali-deacidified SSO (p < 0.05). The contents of the main lipid concomitants such as tocopherols, polyphenols, and phytosterols in UAEE-decidified SSO were significantly higher than those of the latter (p < 0.05). For instance, the DPPH radical scavenging capacity of UAEE-processed SSO was significantly higher than that of alkali refining (p < 0.05). The Pearson bivariate correlation analysis before and after the deacidification process demonstrated that the three main lipid concomitants in SSO were negatively correlated with the index of peroxide, anisidine, and total oxidation values. The purpose of this study was to provide an alternative method for the deacidification of SSO that can effectively remove free fatty acids while maintaining the nutritional characteristics, physicochemical properties, and antioxidant capacity of SSO.


Assuntos
Carthamus tinctorius , Álcalis , Carthamus tinctorius/química , Etanol/química , Peróxidos , Óleos de Plantas/química , Óleo de Cártamo , Tecnologia , Ultrassom
11.
Environ Sci Technol ; 55(6): 4007-4016, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33666414

RESUMO

Bulk metal doping and surface phosphate modification were synergically adopted in a rational design to upgrade the CeO2 catalyst, which is highly active but easily deactivated for the catalytic oxidation of chlorinated volatile organic compounds (Cl-VOCs). The metal doping increased the redox ability and defect sites of CeO2, which mostly promoted catalytic activity and inhibited the formation of dechlorinated byproducts but generated polychlorinated byproducts. The subsequent surface modification of the metal-doped CeO2 catalysts with nonmetallic phosphate completely suppressed the formation of polychlorinated byproducts and, more importantly, enhanced the stability of the surface structure by forming a chainmail layer. A highly active, durable, and selective catalyst of phosphate-functionalized RuOx-CeO2 was the most promising among all the metal-doped (Ru, Pd, Pt, Cr, Mn, Fe, Co, and Cu) CeO2 catalysts investigated owing to the prominent chemical stability of RuOx and its superior versatility in the catalytic oxidation of different kinds of Cl-VOCs and other typical pollutants, including dimethyl sulfide, CO, and C3H8. Moreover, the chemical stability of the catalyst, including its bulk and surface structural stability, was investigated by combining intensive treatment with HCl/H2O or HCl with subsequent ex situ ultraviolet-visible light Raman spectroscopy and confirmed the superior resistance to Cl poisoning of the phosphate-functionalized RuOx-CeO2. This work exemplifies a promising strategy for developing ideal catalysts for the removal of Cl-VOCs and provides a catalyst with the superior catalytic performance in Cl-VOC oxidation to date.


Assuntos
Fosfatos , Catálise , Oxirredução
12.
Chem Biodivers ; 18(3): e2000989, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33528898

RESUMO

Artemisia lavandulaefolia, a traditional herbal medicine, has been utilized as anti-inflammatory and analgesia agent in clinic. Bioassay-guided fractionation resulted in a fraction (ALDF) with anti-inflammatory effect obtained from A. lavandulaefolia. Its main constituents were analyzed and identified by UPLC-ESI-Q-TOF-MS technology. ALDF showed the strong inhibitory activity on the nitrogen oxide (NO) production in LPS-induced RAW 264.7 macrophages with an IC50 value of 1.64±0.41 µg/mL. Further results displayed that ALDF also significantly suppressed the secretion of key pro-inflammatory mediators, including tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2 ) and interleukin-1ß (IL-1ß), and the increase of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression induced by LPS stimulation. Mechanism study indicated that ALDF was able to block NF-κB signaling pathway through inhibiting IκB and p65 phosphorylation, as well as NF-κB p65 nuclear translocation. Furthermore, in vivo results in mice revealed that treatments with ALDF evoked significant inhibition on ear edema induced by xylene and on the writhing responses induced by acetic acid. These results suggest that ALDF holds great potential in the prevention and treatment of inflammatory disorders.


Assuntos
Anti-Inflamatórios/farmacologia , Artemisia/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Ácido Acético , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclo-Oxigenase 2/biossíntese , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese , Dor/induzido quimicamente , Dor/tratamento farmacológico , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Células RAW 264.7 , Estereoisomerismo , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Xilenos
13.
J Anat ; 237(1): 29-47, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32162697

RESUMO

Receptor-interacting protein 3 (RIP3) plays an important role in the necroptosis signaling pathway. Our previous studies have shown that the RIP3/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis occurs in retinal ganglion cell line 5 (RGC-5) following oxygen-glucose deprivation (OGD). However, upstream regulatory pathways of RIP3 are yet to be uncovered. The purpose of the present study was to investigate the role of p90 ribosomal protein S6 kinase 3 (RSK3) in the phosphorylation of RIP3 in RGC-5 cell necroptosis following OGD. Our results showed that expression of RSK3, RIP3, and MLKL was upregulated in necroptosis of RGC-5 after OGD. A computer simulation based on our preliminary results indicated that RSK3 might interact with RIP3, which was subsequently confirmed by co-immunoprecipitation. Further, we found that the application of a specific RSK inhibitor, LJH685, or rsk3 small interfering RNA (siRNA), downregulated the phosphorylation of RIP3. However, the overexpression of rip3 did not affect the expression of RSK3, thereby indicating that RSK3 could be a possible upstream regulator of RIP3 phosphorylation in OGD-induced necroptosis of RGC-5 cells. Moreover, our in vivo results showed that pretreatment with LJH685 before acute high intraocular pressure episodes could reduce the necroptosis of retinal neurons and improve recovery of impaired visual function. Taken together, our findings suggested that RSK3 might work as an upstream regulator of RIP3 phosphorylation during RGC-5 necroptosis.


Assuntos
Necroptose/fisiologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Células Ganglionares da Retina/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Animais , Hipóxia Celular/fisiologia , Linhagem Celular , Simulação por Computador , Camundongos , Fosforilação , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
14.
Int J Syst Evol Microbiol ; 70(11): 5627-5633, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32924914

RESUMO

Two Gram-stain-negative, aerobic, non-motile bacterial strains, 36D10-4-7T and 30C10-4-7T, were isolated from bark canker tissue of Populus × euramericana, respectively. 16S rRNA gene sequence analysis revealed that strain 36D10-4-7T shows 98.0 % sequence similarity to Sphingomonas adhaesiva DSM 7418T, and strain 30C10-4-7T shows highest sequence similarity to Sphingobacterium arenae H-12T (95.6 %). Average nucleotide identity analysis indicates that strain 36D10-4-7T is a novel member different from recognized species in the genus Sphingomonas. The main fatty acids and respiratory quinone detected in strain 36D10-4-7T are C18 : 1 ω7c and/or C18 : 1 ω6c and Q-10, respectively. The polar lipids are diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, aminolipid, phosphatidylethanolamine, sphingoglycolipid, two uncharacterized phospholipids and two uncharacterized lipids. For strain 30C10-4-7T, the major fatty acids and menaquinone are iso-C15 : 0, C16 : 1 ω7c and/or C16 : 1 ω6c and iso-C17 : 0 3-OH and MK-7, respectively. The polar lipid profile includes phosphatidylethanolamine, phospholipids, two aminophospholipids and six unidentified lipids. Based on phenotypic and genotypic characteristics, these two strains represent two novel species within the genera Sphingomonas and Sphingobacterium. The name Sphingomonas corticis sp. nov. (type strain 36D10-4-7T=CFCC 13112T=KCTC 52799T) and Sphingobacterium corticibacterium sp. nov. (type strain 30C10-4-7T=CFCC 13069T=KCTC 52797T) are proposed.


Assuntos
Filogenia , Casca de Planta/microbiologia , Doenças das Plantas/microbiologia , Populus/microbiologia , Sphingobacterium/classificação , Sphingomonas/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/isolamento & purificação , Sphingomonas/isolamento & purificação , Ubiquinona/análogos & derivados , Ubiquinona/química
15.
Int J Syst Evol Microbiol ; 70(2): 897-901, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31778350

RESUMO

One Gram-stain-negative, aerobic, motile bacterial strain, 3-7T, was isolated from symptomatic canker bark tissue of Populus × euramericana. 16S rRNA gene sequence data revealed that the novel isolate shared highest similarity with Sphingomonas panacis DCY99T (98.8 %), and <96.5 % sequence similarity with all other species with validly published names. Growth occurred between 15 and 37 °C and at pH 6.0-9.0, and optimal growth occurred at 30 °C and pH 7.0-8.0. Nitrogen was produced from nitrates. The strain was positive for acetoin production and activity of catalase, oxidase, ß-galactosidase, arginine dihydrolase and ß-glucosidase. The major fatty acids were C16 : 0, C18 : 1ω7c and/or C18 : 1ω6c. The polar lipids of the novel isolate included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, sphingoglycolipid, glycolipid, two uncharacterized phospholipids and two uncharacterized lipids. The respiratory quinones detected in isolate 3-7T were Q-10 (96.9 %) and Q-9 (3.1 %). The DNA G+C content was 65.1 mol%. Based on phenotypic and genotypic characteristics, the isolate represents a novel species within the genus Sphingomonas, for which the name Sphingomonas populi is proposed. The type strain is 3-7T (=CFCC 11561T=LMG 30138T).


Assuntos
Filogenia , Casca de Planta/microbiologia , Populus/microbiologia , Sphingomonas/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonas/isolamento & purificação , Ubiquinona/química
16.
J Asian Nat Prod Res ; 22(3): 241-248, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30585504

RESUMO

Two new nordammarane-type triterpenoids, 3ß-acetoxy-20-oxo-21-nordammaran-23-carboxylic acid methyl ester (1) and 3ß-acetoxy-17ß-dammaranic acid (2), along with two known cycloartane-type triterpenoids (3-4), were isolated from the petroleum ether-soluble extract of Artemisia argyi. Their structures were elucidated based on 1D and 2D NMR spectroscopic data analysis. All compounds were evaluated for their α-glucosidase inhibitory activity in vitro. Compounds 1-4 exhibited significant inhibitory effects on α-glucosidase with IC50 values ranging from 38.34 ± 0.23 to 105.54 ± 0.33 µM.


Assuntos
Artemisia , Triterpenos , Estrutura Molecular , alfa-Glucosidases
17.
Nano Lett ; 19(9): 6377-6384, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31381355

RESUMO

The low Coulombic efficiency and hazardous dendrite growth hinder the adoption of lithium anode in high-energy density batteries. Herein, we report a lithium metal-carbon nanotube (Li-CNT) composite as an alternative to the long-term untamed lithium electrode to address the critical issues associated with the lithium anode in Li-O2 batteries, where the lithium metal is impregnated in a porous carbon nanotube microsphere matrix (CNTm) and surface-passivated with a self-assembled monolayer of octadecylphosphonic acid as a tailor-designed solid electrolyte interphase (SEI). The high specific surface area of the Li-CNT composite reduces the local current density and thus suppresses the lithium dendrite formation upon cycling. Moreover, the tailor-designed SEI effectively separates the Li-CNT composite from the electrolyte solution and prevents the latter's further decomposition. When the Li-CNT composite anode is coupled with another CNTm-based O2 cathode, the reversibility and cycle life of the resultant Li-O2 batteries are drastically elevated.

18.
Int J Syst Evol Microbiol ; 69(7): 1870-1874, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31091182

RESUMO

One Gram-stain negative, aerobic, non-motile bacterial strain, 2c-3T, was isolated from symptomatic canker bark tissue of Populus × euramericana. It was studied by the genome sequence-derived average nucleotide identity (ANI), phylogenetic analysis based on 16S rRNA gene sequences and phenotypic characteristics. 16S rRNA gene data revealed that the novel isolate shares the greatest sequence similarity to Sphingobacterium populi 7Y-4T (97.0 %). The ANI values between the novel isolate and S. populi 7Y-4T was 81.19 %, lower than the proposed species boundary ANI cut-off (95-96 %). The major fatty acids are iso-C15 : 0, C16 : 1ω7c and iso-C17 : 0 3-OH. The polar lipids of the novel isolate included phosphatidylethanolamine, phospholipid, aminophospholipid and unknown lipids (L1-10). The menaquinone of the novel isolate was MK-7. The DNA G+C content was 41.96 mol %. Based on phenotypic and genotypic characteristics, the isolate represents a novel species within the genus Sphingobacterium, for which the name Sphingobacterium corticibacter is proposed. The type strain is 2c-3T (=CFCC 11898T=KCTC 52798T).


Assuntos
Filogenia , Casca de Planta/microbiologia , Populus/microbiologia , Sphingobacterium/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
Int J Syst Evol Microbiol ; 69(4): 1220-1224, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30785392

RESUMO

We isolated five novel bacterial strains from symptomatic bark tissue of Populus × euramericana canker that were Gram-stain-negative, non-motile, aerobic oxidase-negative and catalase-positive. Growth occurred at 10-41 °C and at pH 5.0-7.0, with optimum growth at 30 °C and pH 7.0. Additionally, growth occurred in conditions of 0-5 % (w/v) salinity, but not above 7 % NaCl. The 16S rRNA gene sequences of the novel strains shared the highest similarity with Sinorhodobacter ferrireducens SgZ-3T (97.1 %). The average nucleotide identity values between the novel strains and two type strains (S.inorhodobacter ferrireducens CCTCC AB2012026T and 'Sinorhodobacter hungdaonensis' CGMCC 1.12963T) were 78.4-78.9 %, which were lower than the proposed species boundary cut-off (95-96 %). The main polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified lipid and phosphatidylcholine. The main respiratory quinone was Q-10, and major fatty acids were C18 : 1ω7c and/or C18 : 1ω6c. Based on data from a polyphasic taxonomy study, the novel strains represent a novel species of the genus Sinorhodobacter, for which the name Sinorhodobacter populi sp. nov. is proposed. The type strain is sk2b1T (=CFCC 14580T=KCTC 52802T).


Assuntos
Filogenia , Casca de Planta/microbiologia , Doenças das Plantas/microbiologia , Populus/microbiologia , Rhodobacteraceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Cardenolídeos/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA
20.
J Cell Physiol ; 233(6): 4864-4884, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29334122

RESUMO

Heat shock protein 90α (HSP90α) maintains cell stabilization and regulates cell death, respectively. Recent studies have shown that HSP90α is involved in receptor interacting protein 3 (RIP3)-mediated necroptosis in HT29 cells. It is known that oxygen and glucose deprivation (OGD) can induce necroptosis, which is regulated by RIP3 in neurons. However, it is still unclear whether HSP90α participates in the process of OGD-induced necroptosis in cultured neurons via the regulation of RIP3. Our study found that necroptosis occurs in primary cultured cortical neurons and PC-12 cells following exposure to OGD insult. Additionally, the expression of RIP3/p-RIP3, MLKL/p-MLKL, and the RIP1/RIP3 complex (necrosome) significantly increased following OGD, as measured through immunofluorescence (IF) staining, Western blotting (WB), and immunoprecipitation (IP) assay. Additionally, data from computer simulations and IP assays showed that HSP90α interacts with RIP3. In addition, HSP90α was overexpressed following OGD in cultured neurons, as measured through WB and IF staining. Inhibition of HSP90α in cultured neurons, using the specific inhibitor, geldanamycin (GA), and siRNA/shRNA of HSP90α, protected cultured neurons from necrosis. Our study showed that the inhibitor of HSP90α, GA, rescued cultured neurons not only by decreasing the expression of total RIP3/MLKL, but also by decreasing the expression of p-RIP3/p-MLKL and the RIP1/RIP3 necrosome. In this study, we reveal that inhibition of HSP90α protects primary cultured cortical neurons and PC-12 cells from OGD-induced necroptosis through the modulation of RIP3 expression.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Córtex Cerebral/efeitos dos fármacos , Glucose/deficiência , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Lactamas Macrocíclicas/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Hipóxia Celular , Córtex Cerebral/embriologia , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Regulação para Baixo , Feminino , Idade Gestacional , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Necrose , Neurônios/enzimologia , Neurônios/patologia , Células PC12 , Gravidez , Cultura Primária de Células , Ligação Proteica , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
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