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1.
Inorg Chem ; 63(6): 2954-2966, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38288974

RESUMO

Carbon dioxide (CO2) cycloaddition not only produces highly valued cyclic carbonate but also utilizes CO2 as C1 resources with 100% atomic efficiency. However, traditional catalytic routes still suffer from inferior catalytic efficiency and harsh reaction conditions. Developing multienergy-field catalytic technology with expected efficiency offers great opportunity for satisfied yield under mild conditions. Herein, Zn3In2S6 with sulfur vacancies (Sv) was fabricated with the assistance of cetyltrimethylammonium bromide (CTAB), which is further employed for photothermally driven CO2 cycloaddition first. Photoluminescence spectroscopy and photoelectrochemical characterization demonstrated its superior separation kinetics of photoinduced carriers induced by defect engineering. The temperature-programmed desorption (TPD) technique indicated its excellent Lewis acidity-basicity characters. Due to the combination of above merits from photocatalysis and thermal catalysis, defective Zn3In2S6-Sv achieved a yield as high as 73.2% for cyclic carbonate at 80 °C under blue LED illumination within 2 h (apparent quantum yield of 0.468% under illumination of 380 nm monochromatic light at 36 mW·cm-2), which is 2.9, 2.0, and 6.9 times higher than that in dark conditions and those of pristine Zn3In2S6 and industrial representative tetrabutylammonium bromide (TBAB) thermal-catalysis process under the same conditions, respectively. The synergistic reaction path of photocatalysis and thermal catalysis was discriminated by theoretical calculation. This work provides new insights into the photothermal synergistic catalysis CO2 cycloaddition with defective ternary metal sulfides.

2.
Plant Dis ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654534

RESUMO

Lily (Lilium spp.) is a valuable ornamental bulb flower plant in Liliaceae, and its bulbs have high edible and medicinal value. Compared with bulb propagation of other lilies, seed propagation and short growth period are the most significant characteristics of Lilium×formolongi. In 2023, leaf rot disease (LRD) was observed on approximately 70% of the Lilium×formolongi seedlings sown in an experimental greenhouse in Wuhan, Hubei province, China. Irregular brown water-soaked spots were discovered in the early stages of infected seedlings. Then, spots spread throughout the leaves and caused the leaves to brown, soften, and wilted. A pathogen associated with symptoms was isolated by incubating sterilized leaves on potato dextrose agar plates at 25 ℃ for 2-3 days. Then, a pure single colony was isolated through a single hyphal tip isolation method. The fungal colony was white with abundant aerial mycelium and produced a yellow pigment diffusible into the agar. Microscopically, isolated mycelia were reticulate and pale yellow, while conidia were dark brown, smooth, and spherical, 7.31 to 6.98 × 4.03 to 3.87µm (average 5.44×5.41µm; n=30); oval in lateral view, and had a light stripe in the middle. To identify the species of the fungus at the molecular level, ITS and EF-1α genes were amplified and sequenced using primers ITS1/ITS4 (M Gardes et al. 1993) and 758F/986R (Carbone and Kohn 1999). The BLAST results in GenBank showed that the ITS(OR523578) and EF-1α(PP066842) sequences of LRD shared 99.82% and 99.24% identity with the distinct Apiospora paraphaeosperma strains (GenBank accession MT040110, ON806628.1, respectively). Combined with the morphology of the colony and conidium, the fungus was identified as Ap. paraphaeosperma. In the pathogenicity test, six healthy leaves were inoculated with mycelium disc and then kept in an incubator (22 ℃, 90% humidity, 16h light /8h darkness). The inoculated leaves showed necrosis and wilt symptoms similar to those observed in the greenhouse, while the control leaves were asymptomatic. A re-isolation, morphology identification and DNA sequencing of the fungus confirmed its infection with Ap. paraphaeosperma in Lilium spp. At present, rot caused by Ap. paraphaeosperma has only been reported in Thailand and South Korea, both of which are found on bamboo stems (Hyde et al. 2016; Sun Lul Kwon et al. 2022). As far as we know, this is the first report of leaf rot of lily caused by Ap. paraphaeosperma in China. This report can help identify this disease and further develop effective control measures.

3.
Reproduction ; 165(4): 457-474, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36745023

RESUMO

In brief: Impaired spermatogenesis resulting from disturbed cholesterol metabolism due to intake of high-fat diet (HFD) has been widely recognized, however, the role of preprotein invertase subtilin 9 (PCSK9), which is a negative regulator of cholesterol metabolism, has never been reported. This study aims to reveal the role of PCSK9 on spermatogenesis induced by HFD in mice. Abstract: Long-term consumption of a high-fat diet (HFD) is an important factor that leads to impaired spermatogenesis exhibiting poor sperm quantity and quality. However, the mechanism of this is yet to be elucidated. Disrupted cholesterol homeostasis is one of many crucial pathological factors which could contribute to impaired spermatogenesis. As a negative regulator of cholesterol metabolism, preprotein invertase subtilin 9 (PCSK9) mediates low density lipoprotein receptor (LDLR) degradation to the lysosome, thereby reducing the expression of LDLR on the cell membrane and increasing serum low-density lipoprotein cholesterol level, resulting in lipid metabolism disorders. Here, we aim to study whether PCSK9 is a pathological factor for impaired spermatogenesis induced by HFD and the underlying mechanism. To meet the purpose of our study, we utilized wild-type C57BL/6 male mice and PCSK9 knockout mice with same background as experimental subjects and alirocumab, a PCSK9 inhibitor, was used for treatment. Results indicated that HFD induced higher PCSK9 expression in serum, liver, and testes, and serum PCSK9 is negatively correlated with spermatogenesis, while both PCSK9 inhibitor treatment and PCSK9 knockout methodologies ameliorated impaired lipid metabolism and spermatogenesis in mice fed a HFD. This could be due to the overexpression of PCSK9 induced by HFD leading to dyslipidemia, resulting in testicular lipotoxicity, thus activating the Bcl-2-Bax-Caspase3 apoptosis signaling pathway in testes, particularly in Leydig cells. Our study demonstrates that PCSK9 is an important pathological factor in the dysfunction of spermatogenesis in mice induced by HFD. This finding could provide innovative ideas for the diagnosis and treatment of male infertility.


Assuntos
Dieta Hiperlipídica , Pró-Proteína Convertase 9 , Animais , Masculino , Camundongos , beta-Frutofuranosidase , Colesterol , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9/genética , Sêmen
4.
Br J Dermatol ; 188(1): 84-93, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689521

RESUMO

BACKGROUND: Keloids represent one extreme of aberrant dermal wound healing and are characterized by fibroblast hyperproliferation and excessive deposition of extracellular matrix. Genetics is a major factor for predisposition to keloids and genome-wide association study has identified a single-nucleotide polymorphism (SNP) rs873549 at 1q41 as a susceptibility locus. The SNP rs873549, and the SNPs in strong linkage disequilibrium (LD) with rs873549, may be involved in keloid development. However, the functional significance of these SNPs in keloid pathogenesis remains elusive. OBJECTIVES: To investigate the function and mechanism of SNP rs873549 and the SNPs in strong LD with rs873549 in keloids. METHODS: SNPs in strong LD with rs873549 were analysed using Haploview. The expression levels of the genes near the susceptibility locus were analysed using quantitative real-time polymerase chain reaction. The interaction between rs1348270-containing enhancer and the long noncoding RNA down expressed in keloids (DEIK) (formerly RP11-400N13.1) promoter in fibroblasts was investigated using chromosome conformation capture. The enhancer activity of the rs1348270 locus was evaluated using luciferase reporter assay. Knockdown experiments were used to explore the function of DEIK in keloids. RNA-Seq was performed to investigate the mechanism by which DEIK regulates the expression of collagens POSTN and COMP. RESULTS: rs1348270, an enhancer-located SNP in strong LD with rs873549, mediated looping with the promoter of DEIK. The risk variant was associated with decreased enhancer-promoter interaction and DEIK down-expression in keloids. Mechanistically, downregulation of DEIK increased the expression of collagens POSTN and COMP through upregulating BMP2. Furthermore, correlation analysis revealed that DEIK expression was inversely correlated with BMP2, POSTN and COMP expression in both keloid and normal fibroblasts. CONCLUSIONS: Our findings suggest that the risk variant rs1348270 is located in an enhancer and is associated with the downregulation of DEIK in keloids, and that downregulation of DEIK increases the expression of collagens POSTN and COMP through BMP2 in keloid fibroblasts. These findings will help to provide a more thorough understanding of the role played by genetic factors in keloid development and may lead to new strategies for screening and therapy in keloid-susceptible populations.


Assuntos
Queloide , RNA Longo não Codificante , Humanos , Queloide/patologia , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/metabolismo , Estudo de Associação Genômica Ampla , Regiões Promotoras Genéticas , Fibroblastos/metabolismo
5.
Langmuir ; 39(10): 3762-3769, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36872656

RESUMO

Simultaneously achieving electrochemical conversion of biomass-derived molecules into value-added products and energy-efficient hydrogen production is a highly attractive strategy but challenging. Herein, we reported a heterostructured Ni/Ni0.2Mo0.8N nanorod array electrocatalyst deposited on nickel foam (Ni/Ni0.2Mo0.8N/NF), which exhibited excellent electrocatalytic activity toward 5-hydroxymethylfurfural (HMF) oxidation, and nearly 100% conversion of HMF and 98.5% yield of 2,5-furandicarboxylic acid (FDCA) products can be achieved. The post-reaction characterizations unveil that Ni species in Ni/Ni0.2Mo0.8N/NF would be readily converted to NiOOH as the real active sites. Furthermore, a two-electrode electrolyzer was assembled with Ni/Ni0.2Mo0.8N/NF utilized as a bifunctional electrocatalyst for both the cathode and anode, giving rise to a low voltage of 1.51 V to concurrently produce FDCA and H2 at 50 mA cm-2. This work enlightens the significance of regulating redox activities of transition metals via interfacial engineering and constructing heterostructured electrocatalysts toward more efficient energy utilization.

6.
J Cell Physiol ; 237(2): 1532-1546, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34755904

RESUMO

Endometrial epithelial cells (EECs) and stromal cells (ESCs) have a close functional association. During the peri-implantation period, EECs with enhanced functional activities secrete a variety of paracrine factors to promote the decidualization of ESCs. However, little is known about the specific process by which EECs secrete paracrine factors to induce the decidualization of ESCs. Some evidence suggests that the activation of sodium-glucose cotransporter 3a (SGLT3a) induces the depolarization of ESCs to affect their function. Therefore, SGLT3a acts as a sensor molecule in certain cell types. In this study, the expression of SGLT3a was investigated in EECs to determine whether its levels increased during the peri-implantation period in female mice. The activation of SGLT3a in mouse EECs induced Na+ -dependent depolarization of the cell membrane and an influx of extracellular Ca2+ , which further promoted the expression and release of the paracrine factors prostaglandin E2 (PGE2) and F2-alpha (PGF2α) by upregulating the expression of cyclooxygenase-2. In turn, PGE2 and PGF2α induced the decidualization of ESCs. Importantly, we identified SGLT3a as a key molecule involved in the cross-talk between EECs and ESCs during the process of uterine decidualization.


Assuntos
Decídua , Dinoprostona , Proteínas de Transporte de Sódio-Glucose/metabolismo , Animais , Células Cultivadas , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Camundongos , Células Estromais/metabolismo
7.
Reproduction ; 163(5): 293-307, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35275843

RESUMO

Uterine receptivity to the embryo is crucial for successful implantation. The establishment of uterine receptivity requires a large amount of energy, and abnormal energy regulation causes implantation failure. Glucose metabolism in the endometrium is tissue specific. Glucose is largely stored in the form of glycogen, which is the main energy source for the endometrium. AMP-activated protein kinase (AMPK), an important energy-sensing molecule, is a key player in the regulation of glucose metabolism and its regulation is also tissue specific. However, the mechanism of energy regulation in the endometrium for the establishment of uterine receptivity remains to be elucidated. In this study, we aimed to investigate the energy regulation mechanism of mouse uterine receptivity and its significance in embryo implantation. The results showed that the AMPK, p-AMPK, glycogen synthase 1, and glycogen phosphorylase M levels and the glycogen content in mouse endometrial epithelium varied in a periodic manner under regulation by the ovarian hormone. Specifically, progesterone significantly activated AMPK, promoted glycogenolysis, and upregulated glycogen phosphorylase M expression. AMPK regulated glycogen phosphorylase M expression and promoted glycogenolysis. AMPK was also found to be activated by changes in the energy or glycogen of the endometrial epithelial cells. The inhibition of AMPK activity or glycogenolysis altered the uterine receptivity markers during the window of implantation and ultimately interfered with implantation. In summary, consistency and synchronization of AMPK and glycogen metabolism constitute the core regulatory mechanism in mouse endometrial epithelial cells involved in the establishment of uterine receptivity.


Assuntos
Proteínas Quinases Ativadas por AMP , Glicogênio , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Implantação do Embrião/fisiologia , Endométrio/metabolismo , Células Epiteliais/metabolismo , Feminino , Glicogênio/metabolismo , Camundongos
8.
Small ; 17(30): e2101837, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34145768

RESUMO

Clear cell renal cell carcinoma (ccRCC) is a serious and tenacious disease. Photodynamic therapy (PDT) and photothermal therapy (PTT) are effective means of cancer treatment. However, PDT combined with PTT has been rarely reported in ccRCC treatment. In the present study, by developing the core-shell structured TiO2 @red phosphorus nanorods (TiO2 @RP NRs) as a photosensitizer, the feasibility and effectiveness of synchronous PDT and PTT treatments for ccRCC are demonstrated. The core-shell structured TiO2 @RP NRs are synthesized to drive the PDT and PTT for ccRCC, in which the RP shell is the sensitizer even in the near-infrared (NIR) region. The optimized TiO2 @RP NRs can respond to NIR and produce local heat under irradiation. The NRs are estimated in ccRCC treatments via cell counting kit-8 assay, propidium iodide staining, qRT-PCR, and reactive oxygen species (ROS) probes in vitro, while terminal deoxynucleotidyl transferase dUTP nick-end labeling is conducted in vivo. After NIR irradiation, TiO2 @RP NRs can efficiently kill ccRCC cells by producing local heat and ROS and cause low injury to normal kidney cells. Furthermore, treatment with TiO2 @RP NRs and NIR can kill significant numbers of deep-tissue ccRCC cells in vivo. This work highlights a promising photo-driven therapy for kidney cancer.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Nanotubos , Fotoquimioterapia , Carcinoma de Células Renais/tratamento farmacológico , Ouro , Humanos , Fósforo , Fármacos Fotossensibilizantes , Terapia Fototérmica , Titânio
9.
Reproduction ; 162(6): 397-410, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34554110

RESUMO

The incidence of polycystic ovary syndrome (PCOS) due to high-fat diet (HFD) consumption has been increasing significantly. However, the mechanism by which a HFD contributes to the pathogenesis of PCOS has not been elucidated. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key protein that regulates cholesterol metabolism. Our previous study revealed abnormally high PCSK9 levels in serum from patients with PCOS and in serum and hepatic and ovarian tissues from PCOS model mice, suggesting that PCSK9 is involved in the pathogenesis of PCOS. However, the factor that induces high PCSK9 expression in PCOS remains unclear. In this study, Pcsk9 knockout mice were used to further explore the role of PCSK9 in PCOS. We also studied the effects of a HFD on the expression of PCSK9 and sterol regulatory element-binding protein 2 (SREBP2), a regulator of cholesterol homeostasis and a key transcription factor that regulates the expression of PCSK9, and the roles of these proteins in PCOS pathology. Our results indicated HFD may play an important role by inducing abnormally high PCSK9 expression via SREBP2 upregulation. We further investigated the effects of an effective SREBP inhibitor, fatostain, and found that it could reduce HFD-induced PCSK9 expression, ameliorate hyperlipidemia and improve follicular development in PCOS model mice. Our study thus further elucidates the important role of an HFD in the pathogenesis of PCOS and provides a new clue in the prevention and treatment of this disorder.


Assuntos
Síndrome do Ovário Policístico , Pró-Proteína Convertase 9 , Animais , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Camundongos , Camundongos Knockout , Síndrome do Ovário Policístico/etiologia , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Regulação para Cima
10.
Phys Chem Chem Phys ; 22(23): 13143-13153, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32490855

RESUMO

Polymer dielectrics with high dielectric performances and superior discharge energy capability are highly desirable for advanced electrostatic capacitor applications. However, the paradoxical relationship between dielectric polarization and electric breakdown behavior generally hinder their further enhancement in energy storage performances. Herein, polymer blended composite films with high energy storage capability were successfully fabricated by blending together poly(vinylidene fluoride) (PVDF) polymer and poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)) terpolymer. The P(VDF-TrFE-CFE) terpolymer has a high dielectric constant to provide a large electric displacement under an applied electric field far below its breakdown field, which is anticipated to modulate the dielectric polarization behavior of PVDF polymer when blended in different proportions. Consequently, the polymer blended composite film consisting of 20 wt% (P(VDF-TrFE-CFE)) terpolymer exhibits a high discharge energy density of 13.63 J cm-3 at an enhanced breakdown strength of 480 MV m-1. This obtained high discharge energy density is 84% higher than the pure PVDF film and 582% higher than a commercialized biaxially oriented polypropylene (BOPP). Large interfacial polarization and strong interaction of polymer chains between the PVDF polymer and P(VDF-TrFE-CFE) terpolymer may contribute to the tunable dielectric constant and electric breakdown strength, thus promoting the energy storage capability. This work establishes a facile, but effective approach to achieve the high energy storage capability of PVDF polymer-based flexible composite films for capacitive energy storage applications.

11.
Angew Chem Int Ed Engl ; 59(27): 10888-10893, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32243679

RESUMO

Electrochemical N2 reduction reactions (NRR) and the N2 oxidation reaction (NOR), using H2 O and N2 , are a sustainable approach to N2 fixation. To date, owing to the chemical inertness of nitrogen, emerging electrocatalysts for the electrochemical NRR and NOR at room temperature and atmospheric pressure remain largely underexplored. Herein, a new-type Fe-SnO2 was designed as a Janus electrocatalyst for achieving highly efficient NRR and NOR catalysis. A high NH3 yield of 82.7 µg h-1 mgcat. -1 and a Faraday efficiency (FE) of 20.4 % were obtained for NRR. This catalyst can also serve as an excellent NOR electrocatalyst with a NO3 - yields of 42.9 µg h-1 mgcat. -1 and a FE of 0.84 %. By means of experiments and DFT calculations, it is revealed that the oxygen vacancy-anchored single-atom Fe can effectively adsorb and activate chemical inert N2 molecules, lowering the energy barrier for the vital breakage of N≡N and resulting in the enhanced N2 fixation performance.

12.
Small ; 15(23): e1900816, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31021514

RESUMO

Carbonaceous materials are promising anodes for potassium-ion batteries (PIBs). However, it is hard for large K ions (1.38 Å) to achieve long-distance diffusion in pristine carbonaceous materials. In this work, the following are synthesized: S/N codoped carbon nanofiber aerogels (S/N-CNFAs) with optimized electronic structure by S/N codoping, enhanced interlayer spacing by S doping, and a 3D interconnected porous structure of aerogel, through a pyrolysis sustainable seaweed (Fe-alginate) aerogel strategy. Specifically, the S/N-CNFAs electrode delivers high reversible capacities of 356 and 112 mA h g-1 at 100 and 5000 mA g-1 , respectively. The capacity reaches 168 mA h g-1 at 2000 mA g-1 after 1000 cycles. A full cell with a S/N-CNFAs anode and potassium prussian blue cathode displays a specific capacity of 198 mA h g-1 at 200 mA g-1 . Density functional theory calculations indicate that S/N codoping is beneficial to synergistically improve K ions storage of S/N-CNFAs by enhancing the adsorption of K ions and reducing the diffusion barrier of K ions. This work offers a facile heteroatom doping paradigm for designing new carbonaceous anodes for high-performance PIBs.

13.
Int J Mol Sci ; 20(2)2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654474

RESUMO

Early planting is one of the strategies used to increase grain yield in temperate regions. However, poor cold tolerance in castor inhibits seed germination, resulting in lower seedling emergence and biomass. Here, the elite castor variety Tongbi 5 was used to identify the differential abundance protein species (DAPS) between cold stress (4 °C) and control conditions (30 °C) imbibed seeds. As a result, 127 DAPS were identified according to isobaric tag for relative and absolute quantification (iTRAQ) strategy. These DAPS were mainly involved in carbohydrate and energy metabolism, translation and posttranslational modification, stress response, lipid transport and metabolism, and signal transduction. Enzyme-linked immunosorbent assays (ELISA) demonstrated that the quantitative proteomics data collected here were reliable. This study provided some invaluable insights into the cold stress responses of early imbibed castor seeds: (1) up-accumulation of all DAPS involved in translation might confer cold tolerance by promoting protein synthesis; (2) stress-related proteins probably protect the cell against damage caused by cold stress; (3) up-accumulation of key DAPS associated with fatty acid biosynthesis might facilitate resistance or adaptation of imbibed castor seeds to cold stress by the increased content of unsaturated fatty acid (UFA). The data has been deposited to the ProteomeXchange with identifier PXD010043.


Assuntos
Resposta ao Choque Frio , Proteômica/métodos , Ricinus/metabolismo , Ricinus/fisiologia , Sementes/metabolismo , Estresse Fisiológico , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Genes de Plantas , Germinação , Marcação por Isótopo , Modelos Biológicos , Anotação de Sequência Molecular , Proteínas de Plantas/metabolismo , Reprodutibilidade dos Testes , Ricinus/genética , Transcrição Gênica
14.
J Nanosci Nanotechnol ; 17(1): 720-24, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29633810

RESUMO

Herein we report the facile fabrication and electrocatalytic activity of nanostructured bimetallic iron molybdenum nitride (Fe3Mo3N), which was prepared by an ammonolysis process directly towards the solid state mixture of Mo precursor and Fe precursor. The prepared nanostructured Fe3Mo3N presented remarkable electrocatalytic activities towards both oxygen reduction reaction and oxygen evolution reaction in nonaqueous phase, due to the modulation of electronic configuration of catalyst by Fe element and porous structure. Then, lithium-O2 batteries with nanostructured Fe3Mo3N as cathode catalysts were assembled, which show alleviated polarization and enhanced cyclability.

15.
Anal Chem ; 87(4): 2094-9, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25600185

RESUMO

A droplet-solid interface lipid bilayer membrane (DSLM) with high impedance was developed through controlling the contact area between an aqueous droplet and electrode. The electrode size can be easily controlled from millimeter to micrometer level. The droplet-solid interface lipid bilayer membranes were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and fluorescence microscopy. The fluorescence recovery after photobleaching (FRAP) was applied to determine the diffusion coefficient of egg PC DSLM to be 2.58 µm(2) s(-1). The DSLM resistance can reach up to 26.3 GΩ, which was then used to study the ion channel behavior of melittin. The resistivity of the bilayer membrane decreased linearly with the increase of melittin concentration in the membrane. The high impedance and fluidity of DSLM makes it an ideal model cell membrane system for ion channel study and high-throughput drug screening.


Assuntos
Bicamadas Lipídicas/química , Espectroscopia Dielétrica , Difusão , Impedância Elétrica , Eletrodos , Recuperação de Fluorescência Após Fotodegradação , Meliteno/química , Fluidez de Membrana , Microscopia de Fluorescência , Modelos Moleculares , Fosfatidilcolinas/química
16.
Small ; 11(29): 3550-5, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25824101

RESUMO

Single nanoparticle analysis: An interferometric optical approach calibrates sizes of gold nanoparticles (AuNPs) from the interference intensities by calibrating their interferometric signals against the corresponding transmission electron microscopy measurements. This method is used to investigate whether size affects the diffusion behavior of AuNPs conjugated to supported lipid bilayer membranes and to multiplex the simultaneous detection of three different AuNP labels.


Assuntos
Ouro/análise , Interferometria/normas , Bicamadas Lipídicas/química , Teste de Materiais/normas , Nanopartículas Metálicas/análise , Microscopia Eletrônica de Transmissão/normas , Calibragem/normas , Ouro/química , Tamanho da Partícula , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Zhongguo Zhong Yao Za Zhi ; 40(8): 1605-9, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26281607

RESUMO

The study aims to observe the clinical efficacy of Baoerkang san on spleen-deficiency and dampness-obstructing diarrhea in children. Children diarrhea divided into acute diarrhea (group I) and chronic persistent diarrhea (group II). A randomized, double-blind, positive control test was conducted for dose finding. The 340 cases with acute diarrhea in group I were divided into three groups: the high dose group (112 patients), the low dose group (113 patients) and the positive control group (115 patients), which were treated for 3 days. Their clinical efficacies were compared to evaluate the clinical safety of Baoerkang san. The 167 patients with chronic persistent diarrhea in group If were divided into the high dose group (56 patients), the low dose group (55 patients) and the control group (56 patients), which were treated for 5 days. Their clinical efficacy were compared to evaluate the clinical safety of Baoerkang san. According to the results, the cure rate and the effective rate of acute diarrhea and chronic persistent diarrhea in the high dose group and the low dose group were significantly higher than that of the positive control group (P <0. 05, P < 0.01). In the treatment of spleen-deficiency and dampness-obstructing diarrhea with traditional Chinese medicines, the cure rate and the effective rate of acute diarrhea and chronic persistent diarrhea in the high dose group and the low dose group were significantly higher than that of the positive control group (P < 0.05, P < 0.01). During the test, all of the three groups did not suffer any adverse event, with no any abnormality in general physical indexes. In conclusion, Baoerkang san shows a significant efficacy in treating acute diarrhea and chronic persistent diarrhea (spleen-deficiency and dampness-obstructing) and safe clinical application.


Assuntos
Diarreia/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Criança , Pré-Escolar , Diarreia/fisiopatologia , Feminino , Humanos , Lactente , Masculino , Fitoterapia , Baço/efeitos dos fármacos , Baço/fisiopatologia , Resultado do Tratamento
18.
Anal Chem ; 86(4): 1980-7, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24502773

RESUMO

A facile and effective electrochemical sensing platform for the detection of glucose and urea in one sample without separation was developed using chitosan-reduced graphene oxide (CS-rGO)/concanavalin A (Con A) as a sensing layer. The CS-rGO/Con A with pH-dependent surface net charges exhibited pH-switchable response to negatively charged Fe(CN)6(3-). The principle for glucose and urea detection was essentially based on in situ pH-switchable enzyme-catalyzed reaction in which the oxidation of glucose catalyzed by glucose oxidase or the hydrolyzation of urea catalyzed by urease resulted in a pH change of electrolyte solution to give different electrochemical responses toward Fe(CN)6(3-). It was verified by cyclic voltammograms, differential pulse voltammograms, and electrochemical impedance spectroscopy. The resistance to charge transfer or amperometric current changed proportionally toward glucose concentration from 1.0 to 10.0 mM and urea concentration from 1.0 to 7.0 mM. On the basis of human serum experiments, the sensing platform was proved to be suitable for simultaneous assay of glucose and urea in a practical biosystem. This work not only gives a way to detect glucose and urea in one sample without separation but also provides a potential strategy for the detection of nonelectroactive species based on the enzyme-catalyzed reaction and pH-switchable biosensor.


Assuntos
Técnicas Biossensoriais/métodos , Quitosana/química , Concanavalina A/química , Técnicas Eletroquímicas/métodos , Glucose/análise , Ureia/análise , Grafite/química , Humanos , Concentração de Íons de Hidrogênio , Óxidos/química
19.
Phys Chem Chem Phys ; 16(36): 19206-11, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25096582

RESUMO

Formamidinium (FA) lead triiodide perovskite with chlorine addition (NH2CH=NH2PbI(3-x)Clx) is employed as a light harvester in mesoscopic solar cells for the first time. It is demonstrated that a phase-pure FAPbI(3-x)Clx perovskite layer can be synthesized using a one-step solution-process at 140 °C, and the resultant solar cells deliver a maximum power conversion efficiency of 7.51%, which is the most efficient formamidinium-lead-halide perovskite mesoscopic solar cell employing a polymer hole-transporting layer. The effects of the thermal annealing temperature on the quality/morphology of the perovskite layer and the solar cells performance are discussed. The advantages offered by the one-step solution-processing method and the reduced bandgap make FAPbI(3-x)Clx perovskites an attractive choice for future hybrid photovoltaics.


Assuntos
Amidinas/química , Compostos de Cálcio/química , Fontes de Energia Elétrica , Chumbo/química , Óxidos/química , Polímeros/química , Energia Solar , Titânio/química , Microscopia Eletrônica de Varredura , Soluções , Difração de Raios X
20.
J Cardiothorac Surg ; 19(1): 422, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965617

RESUMO

OBJECTIVE: Coronary artery bypass grafting (CABG) is associated with antithrombotic therapy in terms of postoperative adverse events; however, it is still unknown whether the early use of such drugs after CABG is safe and effective. In this study, we aim to evaluate the relationship between different postoperative antithrombotic strategies and in-hospital adverse events in patients undergoing isolated coronary artery bypass grafting surgery. METHODS: This was a single-center, retrospective cohort analysis of patients undergoing isolated CABG due to coronary artery disease (CAD) between 2001 and 2012. Data were extracted from the Medical Information Mart for Intensive Care III database. The patients involved were divided into the ASA (aspirin 81 mg per day only) or DAPT (aspirin plus clopidogrel 75 mg per day) group according to the antiplatelet strategy. Patients were also stratified into subgroups based on the type of anticoagulation. The in-hospital risk of bleeding and adverse events was investigated and compared between groups. Propensity score matching (PSM) was performed to reduce the potential effects of a selection bias. RESULTS: A total of 3274 patients were included in this study, with 2358 in the ASA group and 889 in the DAPT group. Following the PSM, no significant difference was seen in the risk of major bleeding between the two groups according to the PLATO, TIMI or GUSTO criteria. There was no difference in the postoperative mortality. In subgroup analysis, patients given anticoagulant therapy had an increased incidence of bleeding-related events. Multivariable analysis revealed that postoperative anticoagulant therapy and the early use of heparin, but not DAPT, were independent predictors of bleeding-related events. CONCLUSIONS: Postoperative DAPT was not associated with an increased occurrence of bleeding-related events in patients undergoing isolated CABG and appears to be a safe antiplatelet therapy. The addition of anticoagulants to antiplatelet therapy increased the risk of bleeding and should be considered cautiously in clinical practice.


Assuntos
Ponte de Artéria Coronária , Fibrinolíticos , Inibidores da Agregação Plaquetária , Estudos Retrospectivos , Estudos de Coortes , Ponte de Artéria Coronária/efeitos adversos , Período Pós-Operatório , Fibrinolíticos/uso terapêutico , Clopidogrel/uso terapêutico , Aspirina/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Quimioterapia Combinada , Hemorragia/prevenção & controle , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso
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