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1.
J Asian Nat Prod Res ; 26(8): 883-891, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38602500

RESUMO

Four new tirucallane-type triterpenoids, polystanins H-K (1-4), were obtained from the stems and leaves of Aphanamixis polystachya. Their structures were elucidated by analysis of the spectroscopic data and comparison with literature data. Compounds 1 and 2 showed week inhibitory effects against NO production in LPS-stimulated RAW264.7 cells. All the isolates were investigated for their antifungal activities against drug-resistant Candida albicans.


Assuntos
Antifúngicos , Candida albicans , Óxido Nítrico , Triterpenos , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Camundongos , Animais , Estrutura Molecular , Candida albicans/efeitos dos fármacos , Células RAW 264.7 , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Folhas de Planta/química , Testes de Sensibilidade Microbiana , Lipopolissacarídeos/farmacologia , Meliaceae/química , Caules de Planta/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação
2.
Int Ophthalmol ; 44(1): 130, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478099

RESUMO

PURPOSE: This study seeks to build a normative database for the vessel density of the superficial retina (SVD) and evaluate how changes and trends in the retinal microvasculature may be influenced by age and axial length (AL) in non-glaucomatous eyes, as measured with optical coherence tomography angiography (OCTA). METHODS: We included 500 eyes of 290 healthy subjects visiting a county hospital. Each participant underwent comprehensive ophthalmological examinations and OCTA to measure the SVD and thickness of the macular and peripapillary areas. To analyze correlations between SVD and age or AL, multivariable linear regression models with generalized estimating equations were applied. RESULTS: Age was negatively correlated with the SVD of the superior, central, and inferior macular areas and the superior peripapillary area, with a decrease rate of 1.06%, 1.36%, 0.84%, and 0.66% per decade, respectively. However, inferior peripapillary SVD showed no significant correlation with age. AL was negatively correlated with the SVD of the inferior macular area and the superior and inferior peripapillary areas, with coefficients of -0.522%/mm, -0.733%/mm, and -0.664%/mm, respectively. AL was also negatively correlated with the thickness of the retinal nerve fiber layer and inferior ganglion cell complex (p = 0.004). CONCLUSION: Age and AL were the two main factors affecting changes in SVD. Furthermore, AL, a relative term to represent the degree of myopia, had a greater effect than age and showed a more significant effect on thickness than on SVD. This relationship has important implications because myopia is a significant issue in modern cities.


Assuntos
Miopia , Vasos Retinianos , Humanos , Retina , Tomografia de Coerência Óptica/métodos , Fibras Nervosas , Envelhecimento
3.
Chemistry ; 30(18): e202303741, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38206884

RESUMO

Compared with Li+, Na+ with a smaller stokes radius has faster de-solvation kinetics. An electrolyte with ultralow sodium salt (0.3 M NaPF6) is used to reduce the cell cost. However, the organic-dominated interface, mainly derived from decomposed solvents (SSIP solvation structure), is defective for the long cycling performance of sodium ion batteries. In this work, the simple application of dual additives, including sodium difluoro(oxalato)borate (NaDFOB) and tris(trimethylsilyl)borate (TMSB), is demonstrated to improve the cycling performance of the hard carbon/NaNi1/3Fe1/3Mn1/3O2 cell by constructing interface films on the anode and cathode. A significant improvement on cycling stability has been achieved by incorporating dual additives of NaDFOB and TMSB. Particularly, the capacity retention increased from 17 % (baseline) to 79 % (w/w, 2.0 wt % NaDFOB) and 83 % (w/w, 2.0 wt % NaDFOB and 1.0 wt % TMSB) after 200 cycles at room temperature. Insight into the mechanism of improved interfacial properties between electrodes and electrolyte in ultralow concentration electrolyte has been investigated through a combination of theoretical computation and experimental techniques.

4.
J Colloid Interface Sci ; 638: 109-122, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36736113

RESUMO

Metal oxide-oxide interface on supported catalyst has been rarely studied due to the complex interfacial structure and synthetic challenge. Herein, different Ag-supported CeO2/Co3O4 samples with various covered-state of CeO2 were prepared for catalytic soot oxidation. In comparison, catalytic activity was significantly improved by grafting CeO2 on Co3O4, in which the best performing Ag/CoCe-2 exhibited remarkable catalytic performance towards soot oxidation with a T50 of 290.5 â„ƒ under 10 % O2/N2. Catalyst characterization investigated by Scanning Electron Microscope (SEM), quasi in-situ X-ray Photoelectron Spectroscopy (XPS), in-situ Raman, etc. revealed that this outstanding promotion in catalytic activity can be principally ascribed to the formation of the CeO2/Co3O4 interface. An appropriate CeO2 dosage maximized the contact and interaction between Co3O4 and CeO2, resulting in the largest CeO2/Co3O4 interface featured with abundant generated superoxide species and activated surface lattice oxygen. Density functional theory (DFT) calculations were also carried out for the oxygen vacancy formation energy, Gibbs free energy, etc. In presence of the CeO2/Co3O4 interface, a charge density redistribution around the adsorbed reactants at oxygen vacancies could be formed, owing to the efficient charge transfer enhanced by the electron-appealing effect. The change in electronic structure favored reducing the oxygen vacancy formation energy and boosting the lattice oxygen activation induced by the hybridized Co-O-Ce bonds, finally lowering the adsorption and activation barriers for reactive species and accelerating the reaction kinetics.


Assuntos
Cério , Oxigênio , Oxigênio/química , Fuligem/química , Cério/química , Óxidos/química
5.
BMC Med Imaging ; 22(1): 206, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36434508

RESUMO

BACKGROUND: Glaucoma is one of the major causes of blindness; it is estimated that over 110 million people will be affected by glaucoma worldwide by 2040. Research on glaucoma detection using deep learning technology has been increasing, but the diagnosis of glaucoma in a large population with high incidence of myopia remains a challenge. This study aimed to provide a decision support system for the automatic detection of glaucoma using fundus images, which can be applied for general screening, especially in areas of high incidence of myopia. METHODS: A total of 1,155 fundus images were acquired from 667 individuals with a mean axial length of 25.60 ± 2.0 mm at the National Taiwan University Hospital, Hsinchu Br. These images were graded based on the findings of complete ophthalmology examinations, visual field test, and optical coherence tomography into three groups: normal (N, n = 596), pre-perimetric glaucoma (PPG, n = 66), and glaucoma (G, n = 493), and divided into a training-validation (N: 476, PPG: 55, G: 373) and test (N: 120, PPG: 11, G: 120) sets. A multimodal model with the Xception model as image feature extraction and machine learning algorithms [random forest (RF), support vector machine (SVM), dense neural network (DNN), and others] was applied. RESULTS: The Xception model classified the N, PPG, and G groups with 93.9% of the micro-average area under the receiver operating characteristic curve (AUROC) with tenfold cross-validation. Although normal and glaucoma sensitivity can reach 93.51% and 86.13% respectively, the PPG sensitivity was only 30.27%. The AUROC increased to 96.4% in the N + PPG and G groups. The multimodal model with the N + PPG and G groups showed that the AUROCs of RF, SVM, and DNN were 99.56%, 99.59%, and 99.10%, respectively; The N and PPG + G groups had less than 1% difference. The test set showed an overall 3%-5% less AUROC than the validation results. CONCLUSION: The multimodal model had good AUROC while detecting glaucoma in a population with high incidence of myopia. The model shows the potential for general automatic screening and telemedicine, especially in Asia. TRIAL REGISTRATION: The study was approved by the Institutional Review Board of the National Taiwan University Hospital, Hsinchu Branch (no. NTUHHCB 108-025-E).


Assuntos
Glaucoma , Miopia , Humanos , Prevalência , Grupos Focais , Glaucoma/diagnóstico por imagem , Glaucoma/epidemiologia , Miopia/diagnóstico por imagem , Miopia/epidemiologia , Inteligência Artificial
6.
Materials (Basel) ; 15(14)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35888341

RESUMO

Commercial polyolefin separators exhibit problems including shrinkage under high temperatures and poor electrolyte wettability and uptake, resulting in low ionic conductivity and safety problems. In this work, core-shell silica-polyphosphazene nanoparticles (SiO2@PZS) with different PZS layer thicknesses were synthesized and coated onto both sides of polyethylene (PE) microporous membranes to prepare composite membranes. Compared to pure silica-coated membranes and PE membranes, the PE-SiO2@PZS composite membrane had higher ionic conductivity. With the increase in the SiO2@PZS shell thickness, the electrolyte uptake, ionic conductivity and discharge capacity gradually increased. The discharge capacity of the PE-SiO2@PZS composite membrane at 8 C rate was 129 mAh/g, which was higher than the values of 107 mAh/g for the PE-SiO2 composite membrane and 104 mAh/g for the PE membrane.

7.
Chemosphere ; 291(Pt 2): 132778, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34742759

RESUMO

To develop novel catalysts of high-performance and cost-effectiveness, and to investigate the reaction kinetics of CO oxidation, ternary CuCeFeOx catalysts supported on zeolite/PSF (porous stainless-steel fibers) were synthesized for the first time. Effects of different Ce/Fe ratios, loading amounts, calcination temperatures, and reaction kinetics were investigated. Remarkably improved catalytic performance was achieved in the PSF-supported catalysts compared to the granular ones, owing to the increased mass/heat transfer efficiency and the high dispersion of active metal oxide species anchored on the zeolite layer. The Cu3Ce12Fe4-400 sample exhibited the best catalytic activity with a temperature difference in T90 of almost 40 °C lower than the worst one. Characterization results from XRD, FTIR, TEM, XPS, H2-TPR, etc. revealed that the promoted reducibility of metal oxides and formation of more oxygen vacancies significantly contributed to the enhanced catalytic activity. Furthermore, a generalized rate expression was derived from intrinsic and macro kinetic studies by assuming the conversion of CO to CO2 as the rate-determining step, in which CO oxidation over the PSF-supported catalysts followed the pseudo-first-order kinetic established by the Langmuir-Hinshelwood type mechanism.


Assuntos
Zeolitas , Catálise , Cinética , Porosidade , Aço Inoxidável
8.
Biomed Res Int ; 2020: 4094191, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32685480

RESUMO

During a spaceflight, astronauts need to live in a spacecraft on orbit for a long time, and the relationship between humans and microorganisms in the closed environment of space is not the same as on the ground. The dynamic study of microorganisms in confined space shows that with the extension of the isolation time, harmful bacteria gradually accumulate. Monitoring and controlling microbial pollution in a confined environment system are very important for crew health and the sustainable operation of a space life support system. Culture-based assays have been used traditionally to assess the microbial loads in a spacecraft, and uncultured-based techniques are already under way according to the NASA global exploration roadmap. High-throughput sequencing technology has been used generally to study the communities of the environment and human on the ground and shows its broad prospects applied onboard. We here review the recent application of high-throughput sequencing on space microbiology and analyze its feasibility and potential as an on-orbit detection technology.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Microbiologia , Voo Espacial , Humanos , Sequenciamento por Nanoporos
9.
Front Microbiol ; 11: 617696, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33613468

RESUMO

Confined experiments are carried out to simulate the closed environment of space capsule on the ground. The Chinese Controlled Ecological Life Support System (CELSS) is designed including a closed-loop system supporting 4 healthy volunteers surviving for 180 days, and we aim to reveal the temporal characteristics of the oropharyngeal and nasal microbiota structure in crewmembers stayed 180 days in the CELSS, so as to accumulate the information about microbiota balance associated with respiratory health for estimating health risk in future spaceflight. We investigated the distribution of microorganisms and their dynamic characteristics in the nasal cavity and oropharynx of occupants with prolonged confinement. Based on the 16S rDNA v3-v4 regions using Illumina high-throughput sequencing technology, the oropharyngeal and nasal microbiota were monitored at eight time points during confinement. There were significant differences between oropharyngeal and nasal microbiota, and there were also individual differences among the same site of different volunteers. Analysis on the structure of the microbiota showed that, in the phylum taxon, the nasal bacteria mainly belonged to Actinobacteria, Firmicutes, Proteobacteria, Bacteroidetes, etc. In addition to the above phyla, in oropharyngeal bacteria Fusobacterial accounted for a relatively high proportion. In the genus taxon, the nasal and oropharyngeal bacteria were independent. Corynebacterium and Staphylococcus were dominant in nasal cavity, and Corynebacterium, Streptococcus, and Neisseria were dominant in oropharynx. With the extension of the confinement time, the abundance of Staphylococcus in the nasal cavity and Neisseria in the oropharynx increased, and the index Chao fluctuated greatly from 30 to 90 days after the volunteers entered the CELSS. Conclusion: The structure and diversity of the nasal and oropharyngeal microbiota changed in the CELSS, and there was the phenomenon of migration between occupants, suggesting that the microbiota structure and health of the respiratory tract could be affected by living in a closed environment for a long time.

10.
Int J Syst Evol Microbiol ; 69(6): 1689-1695, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30942688

RESUMO

A Gram-stain-negative, rod-shaped bacterium, designated Ery1T, was isolated from deep-sea seawater collected from the Mariana Trench and subjected to a polyphasic investigation for taxonomy. Strain Ery1T was able to grow in medium containing 0-10 % NaCl (w/v; optimum, 0-1.0 %), pH 5.0-9.5 (optimum, pH 6.0-7.0) and at temperatures between 10-45 °C (optimum, 30-40 °C). The comparison of 16S rRNA gene sequences revealed that strain Ery1T showed highest similarity to Altererythrobacterxinjiangensis S3-63T (97.7 %) and Altererythrobacterrigui WW3T (97.6 %), and exhibited less than 97.5 % sequence similarity to other type strains of the species with validly published names. Phylogenetic analyses indicated that strain Ery1T fell within the cluster comprising the Altererythrobacter species and formed a coherent clade with Altererythrobacterxinjiangensis and Altererythrobactersoli. The OrthoANIu and in silico DNA-DNA hybridization values between strain Ery1T and the reference strains were 73.8-75.9 % and 19.2-20.1 %, respectively. Strain Ery1T contained Q-10 as the major respiratory quinone and Q-11 in a minor amount. The major fatty acids (>10 %) were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and C14 : 0 2-OH. The major polar lipids were sphingoglycolipid, diphosphatidylglycerol, phosphatidyglycerol, phatidylethanolamine, phosphatidylcholine and three unidentified glycolipids. Differential phenotypic properties, chemotaxonomic differences, phylogenetic distinctiveness, together with the genomic data demonstrated that strain Ery1T represents a novel species of the genus Altererythrobacter, for which named as Altererythrobacter aerophilus sp. nov. with the type strain Ery1T (=KCTC 62387T=CGMCC 1.16499T=MCCC 1A10037T).


Assuntos
Alphaproteobacteria/classificação , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
11.
Int J Syst Evol Microbiol ; 67(10): 3733-3738, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28895511

RESUMO

A novel bacterial strain, designated HSG9T, was isolated from aisolated from a rotten tropical mangrove root. Cells of strain HSG9T were aerobic, Gram-stain-negative, yellow, oxidase-negative and catalase-positive. Growth was observed in 0.5-9 % sea salt (optimum 3 %, w/v), at 10-42 °C (optimum 25-35 °C) and at pH 6.0-8.0 (optimum 7.0-8.0). Gelatin, esterase and Tweens 20, 40, 60 and 80 were hydrolysed, but starch, protein, cellulose and casein were not. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain HSG9T formed an independent lineage related to the family Flavobacteriaceae. The dominant fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G. The respiratory quinone was identified as MK-6 and the polar lipids were phosphatidylethanolamine, three unidentified phospholipids and an unidentified lipid. The DNA G+C content was 37.1 mol%. The combined genotypic and phenotypic data indicated that strain HSG9T represents a novel species of a new genus within the family Flavobacteriaceae, for which the name Croceivirgaradicis gen. nov., sp. nov. is proposed. The type strain is HSG9T (=MCCC 1A06690T=KCTC 52589T).


Assuntos
Avicennia/microbiologia , Flavobacteriaceae/classificação , Filogenia , Raízes de Plantas/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/genética , Flavobacteriaceae/isolamento & purificação , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
Int J Biol Macromol ; 86: 338-44, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26826287

RESUMO

In this study, an environmentally friendly biosorbent deacetylated konjac glucomannan conjugated soy protein isolate (abbreviated as DKGM-C-SPI) was prepared for Cu(2+) ions removal from aqueous solution. Scanning electron microscopy, Fourier transform infrared spectroscopy and zeta potential analysis revealed successful conjugation of soy protein isolate (SPI) onto deacetylated konjac glucomannan (DKGM) matrix. A comparative adsorption performance of DKGM-C-SPI and DKGM was tested to remove Cu(2+) ions from aqueous solution. DKGM-C-SPI showed the desired adsorption performance for Cu(2+) ions. The adsorption equilibrium of DKGM-C-SPI was achieved within 30 min. The adsorption behavior of DKGM-C-SPI followed a pseudo-second-order reaction model. The maximum Cu(2+) ion adsorption capacities obtained from the Langmuir isotherms fit were shown to be 62.50 mg g(-1) for DKGM-C-SPI and 12.23 mg g(-1) for DKGM. This impressive increase about 5 times in Cu(2+) ion adsorption capacity is attributed to the strong Cu(2+) ion chelating ability of the soy protein isolate (SPI) on the DKGM matrix. These results confirm that the DKGM-C-SPI biosorbent has a potential for Cu(2+) ion extraction from wastewater.


Assuntos
Cobre/química , Cobre/isolamento & purificação , Mananas/química , Proteínas de Soja/química , Poluentes Radioativos da Água/química , Poluentes Radioativos da Água/isolamento & purificação , Acetilação , Adsorção , Química Verde , Concentração de Íons de Hidrogênio , Cinética
13.
Nanotechnology ; 21(17): 175701, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20357407

RESUMO

Multilayer ordered GeSi quantum dots (QDs) with thin Si spacers were obtained via self-assembly on pit-patterned Si(001) substrates. The lateral ordering of GeSi QDs predetermined by the periodic pit pattern results in remarkably improved size uniformity in comparison with random QDs on flat substrates. A much stronger and narrower photoluminescence (PL) peak from ordered QDs were observed than that from random ones, particularly at high excitation power. Such enhanced PL signal was attributed to the high density of states and the uniform distribution of excitons in the ordered and uniform QDs, which can efficiently suppress the Auger effect and the Coulomb screening effect. Moreover, anomalous narrowing of the PL peak from the ordered QDs with the excitation power was observed, which was explained in terms of distributed feedback associated with the periodic stacked GeSi QDs.


Assuntos
Germânio/química , Nanopartículas/química , Pontos Quânticos , Silício/química , Eletroquímica , Luminescência , Microscopia Eletrônica de Transmissão , Tamanho da Partícula
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