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1.
Small ; 20(4): e2307553, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37715063

RESUMO

In situ forming gel polymer electrolyte (GPE) is one of the most feasible ways to improve the safety and cycle performances of lithium metal batteries with high energy density. However, most of the in situ formed GPEs are not compatible with high-voltage cathode materials. Here, this work provides a novel strategy to in situ form GPE based on the mechanism of Ritter reaction. The Ritter reaction in liquid electrolyte has the advantage of appropriate reaction temperature and no additional additives. The polymer chains are cross-linked by amide groups with the formation of GPE with superior electrochemical properties. The GPE has high ionic conductivity (1.84 mS cm-1 ), wide electrochemical stability window (>5.25 V) and high lithium ion transference number (≈0.78), compatible with high-voltage cathode materials. The Li|LiNi0.6 Co0.2 Mn0.2 O2 batteries with in situ formed GPE show excellent long-term cycle stability (93.4%, 300 cycles). The density functional theory calculation and X-ray photoelectron spectroscopy results verify that the amide and nitrile groups are beneficial for stabilizing cathode structure and promoting uniform Li deposition on Li anode. Furthermore, the in situ formed GPE exhibits excellent electrochemical performance in Graphite|LiMn2 O4 and Graphite|LiNi0.5 Co0.2 Mn0.3 O2 pouch batteries. This approach is adaptable to current battery technologies, which will be sure to promote the development of high energy-density lithium-ion batteries.

2.
Mol Biol Evol ; 39(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718707

RESUMO

Evolutionary radiation is a widely recognized mode of species diversification, but its underlying mechanisms have not been unambiguously resolved for species-rich cosmopolitan plant genera. In particular, it remains largely unknown how biological and environmental factors have jointly driven its occurrence in specific regions. Here, we use Rhododendron, the largest genus of woody plants in the Northern Hemisphere, to investigate how geographic and climatic factors, as well as functional traits, worked together to trigger plant evolutionary radiations and shape the global patterns of species richness based on a solid species phylogeny. Using 3,437 orthologous nuclear genes, we reconstructed the first highly supported and dated backbone phylogeny of Rhododendron comprising 200 species that represent all subgenera, sections, and nearly all multispecies subsections, and found that most extant species originated by evolutionary radiations when the genus migrated southward from circumboreal areas to tropical/subtropical mountains, showing rapid increases of both net diversification rate and evolutionary rate of environmental factors in the Miocene. We also found that the geographically uneven diversification of Rhododendron led to a much higher diversity in Asia than in other continents, which was mainly driven by two environmental variables, that is, elevation range and annual precipitation, and were further strengthened by the adaptation of leaf functional traits. Our study provides a good example of integrating phylogenomic and ecological analyses in deciphering the mechanisms of plant evolutionary radiations, and sheds new light on how the intensification of the Asian monsoon has driven evolutionary radiations in large plant genera of the Himalaya-Hengduan Mountains.


Assuntos
Rhododendron , Ásia , Evolução Biológica , Filogenia , Plantas , Rhododendron/genética
3.
J Dairy Sci ; 106(10): 6655-6670, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37210356

RESUMO

In this study, we aimed to detect the physicochemical properties of distilled products (residue and distillate) obtained from anhydrous milk fat (AMF) and its dry fractionation products (liquid and solid fractions at 25°C [25 L and 25 S]). The results showed that the saturated fatty acids and low- and medium molecular-weight triglycerides were easily accumulated in the distillate, and the percentage of unsaturated fatty acid and high molecular-weight triglycerides in the residue were higher, and these components in 25 S and 25 L were influenced more significantly than those in the AMF. In addition, the distillate had larger melting ranges in comparison with the distilled substrate, while the melting ranges of residue was smaller. The triglycerides were presented as the mixture crystal forms (α, ß', and ß crystal) in 25 S, AMF, and their distilling products, and it was transformed gradually to a single form as the increasing of distilling temperature. Moreover, the accumulated pattern of triglycerides was double chain length in 25 S, AMF, and their distilling products. These results provide a new approach to obtain the milk fat fractions with different properties, and the findings of this study enrich the theoretical basis of milk fat separation in practical production.


Assuntos
Ácidos Graxos , Leite , Animais , Ácidos Graxos/análise , Triglicerídeos/análise , Leite/química , Destilação , Fracionamento Químico
4.
J Pediatr ; 231: 278-283.e2, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33359301

RESUMO

ABCA3 deficiency is a rare cause of neonatal respiratory failure. Biallelic complete loss of function variants lead to neonatal demise without lung transplantation, but children with partial function variants have variable outcomes. The favorable clinical course of 3 such infants presenting with respiratory distress at birth is described.


Assuntos
Transportadores de Cassetes de Ligação de ATP/deficiência , Transportadores de Cassetes de Ligação de ATP/genética , Síndrome do Desconforto Respiratório do Recém-Nascido/genética , Humanos , Recém-Nascido , Masculino , Mutação , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia
5.
Microb Cell Fact ; 20(1): 10, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413411

RESUMO

BACKGROUND: Freezing stress is the key factor that affecting the cell activity and fermentation performance of baker's yeast in frozen dough production. Generally, cells protect themselves from injury and maintain metabolism by regulating gene expression and modulating metabolic patterns in stresses. The Snf1 protein kinase is an important regulator of yeast in response to stresses. In this study, we aim to study the role of the catalytic subunit of Snf1 protein kinase in the cell tolerance and dough leavening ability of baker's yeast during freezing. Furthermore, the effects of SNF1 overexpression on the global gene expression and metabolite profile of baker's yeast before and after freezing were analysed using RNA-sequencing and untargeted UPLC - QTOF-MS/MS, respectively. RESULTS: The results suggest that overexpression of SNF1 was effective in enhancing the cell tolerance and fermentation capacity of baker's yeast in freezing, which may be related to the upregulated proteasome, altered metabolism of carbon sources and protectant molecules, and changed cell membrane components. SNF1 overexpression altered the level of leucin, proline, serine, isoleucine, arginine, homocitrulline, glycerol, palmitic acid, lysophosphatidylcholine (LysoPC), and lysophosphatidylethanolamine (LysoPE) before freezing, conferring cells resistance in freezing. After freezing, relative high level of proline, lysine, and glycerol maintained by SNF1 overexpression with increased content of LysoPC and LysoPE. CONCLUSIONS: This study will increase the knowledge of the cellular response of baker's yeast cells to freezing and provide new opportunities for the breeding of low-temperature resistant strains.


Assuntos
Congelamento , Regulação Fúngica da Expressão Gênica , Metaboloma , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transcriptoma , Temperatura Baixa , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética
6.
J Org Chem ; 86(9): 6800-6812, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33899472

RESUMO

A hypervalent iodine(III)-mediated ring-contractive fluorination reaction of 2-alkylidenecyclobutanol derivatives is presented. The protocol allows the facile synthesis of ß-monofluorinated cyclopropanecarbaldehydes via a fluorination/semipinacol rearrangement cascade using nucleophilic Py·HF as the fluorine source. For challenging electron-rich arene substrates, the installation of a protecting group on the free alcohol is pivotal for maintaining the reaction efficiency. The synthetic utility was demonstrated by the scalability of this reaction and further transformations of the products.


Assuntos
Halogenação , Iodo , Cicloexenos , Estrutura Molecular
7.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2691-2698, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34296565

RESUMO

Astragali Radix is one of the most commonly used medicinal materials. In recent years, its cultivated varieties and a variety of adulterants have flooded the market, which makes its quality uneven, and the development of quality control methods has become a research hotspot. Therefore, figuring out the quality markers of Astragali Radix is of great significance for its comprehensive evaluation. In this study, the fingerprints of 15 batches of Astragali Radix were established by HPLC, and the main components causing intergroup differences were screened out by PLS-DA. On the basis of literature review and network pharmacology analysis, the targets and pathways of active ingredients were obtained from SwissTargetPrediction, PubChem Compound and other databases, and then the "component-target-pathway" network was constructed with Cytoscape 3.7.1 for the prediction of potential quality markers. Twenty-eight common peaks were identified in the established fingerprint, and three differential components were selected as potential quality markers for Astragali Radix, which were astragaloside Ⅳ, calycosin-7-O-ß-D-glucoside and ononin. The proposed method based on HPLC fingerprint of Astragali Radix is convenient and feasible, facilitating the improvement in its quality control.


Assuntos
Astrágalo , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Raízes de Plantas , Controle de Qualidade
8.
Zhongguo Zhong Yao Za Zhi ; 46(21): 5641-5649, 2021 Nov.
Artigo em Zh | MEDLINE | ID: mdl-34951217

RESUMO

This Radix study cum aims Melle to explore(HRPM)the on efficacy spleen differences deficiency between syndrome.modeling Astragali A Radix of Praeparata110cum rats Melle were(ARPM)randomized fatigue),and into rats Hedysari a Praeparata(n qi total irregular HRPM male diet,SD diarrhea,control were(n Yiqi=10)the=100).Pill group fied and model a modeling group,group Buzhong After(BYP)(through ARPM and the HRPM-H),classimedium-dose into(ARPM-M raised group,and high-dose(ARPM-H each and Rats BYP and under HRPM-M),normal and low-dose and(ARPM-L in and group HRPM-L)were groups,continuously10rats induced.were in group.the in group the were18.9,control given group were g·kg~(-1)conditions while those the the model Rats respectively in18.912.6,BYP kg~(-1)water extract,decoction those in ARPM/HRPM-H,the-M,dosage lasted and of-L groups treated the with control and model6.3group g·rewere motilin determined m L·kg~(-1)·day~(-1).days.of dose Spleen ARPM/HRPM of in water.morning,The at the10Rats spleen in index group thymus and index ceived equal calculated.(MTL),distilled tissue administration to15observe Then the and Routine of each group D-xylose,were was(IL-2),the subjected HE stainingγ(IFN-γ),lower to the pathological changes.(IgA),blood gastric indexes,mucosa index,interleukin-2group.interferon group immunoglobulin of A and spleen pepsin index,of in Ig A,IL-2spleen IFN-γ,control each MTL,levels Rats pepsin the in model(P<0.01),had higher levels routine(P<0.01),blood and indexes,more thymus lesions D-xylose,the and in index,level decreased HRPM-L of IL-2severe compared spleen with than the those model in group.thymus group.that(P<0.05group,P<0.01)index administration thymus groups Ig A or spleen as that and in spleen routine Except index,spleen the Ig A,index,group and were in in ARPM-M model group,group,index,indexes,P<0.01)and thymus MTL index,those in ARPM-L insignificantly Ig A,different pepsin from other those in the the blood index,compared IFN-γ,group,(P<0.05The D-xylose,model MTL,spleen and lesions high-dose in each administration administration groups group increased relieved.blood or comparison as of with HRPM in as the folARPM and the effect in and were white and result than ARPM and is of lows:(P stronger<0.05),of medium-dose high-dose HRPM HRPM on IL-2cell high-dose of(WBC)and count medium-dose the HRPM and corresponding doses than IFN-γmore ARPM the obvious effect(P<0.05of on evident(P<0.05of impact P<0.01),on low-dose between the on corresponD-xylose P<0.01),doses ding MTL doses than Meanwhile,in of or more high-dose,and medium-dose,difference HRPM the and indexes.corresponding there of ARPM in or IL-2no levels in the HRPM-L effect and two groups,on but conclusion,other the both functions IFN-γwas group no was difference more the than recovery that of the and ARPM-H between(IL-2,P<0.01;ARPM-L recovery HRPM the IFN-γ,P<0.05).HRPM-H and obvious therapeutic in rats group qi In ARPM dose have are certain equivalent,effects on with spleen function deficiency.the Specifically,is the better difference immunomodulatory of two at g·low kg~(-1).and but the promote immunomodulatory the of former rats significantly ARPM.than that between of the later two at in the dose>18.9HRPM promotion can of better digestion digestion absorption and may absorption due of than The immunoregulation and be to the difference in clinical medication.


Assuntos
Astrágalo , Medicamentos de Ervas Chinesas , Animais , Raízes de Plantas , Ratos , Baço
9.
Microb Cell Fact ; 19(1): 134, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32571355

RESUMO

BACKGROUND: The Saccharomyces cerevisiae Snf1 complex is a member of the AMP-activated protein kinase family and plays an important role in response to environmental stress. The α catalytic subunit Snf1 regulates the activity of the protein kinase, while the ß regulatory subunits Sip1/Sip2/Gal83 specify substrate preferences and stress response capacities of Snf1. In this study, we aim to investigate the effects of SNF1 overexpression on the cell tolerance and glucose consumption of S. cerevisiae in high glucose, ethanol, and heat stresses and to explore the valid Snf1 form in the light of ß subunits in these stresses. RESULTS: The results suggest that overexpression of SNF1 is effective to improve cell resistance and glucose consumption of S. cerevisiae in high glucose, ethanol, and heat stresses, which might be related to the changed accumulation of fatty acids and amino acids and altered expression levels of genes involved in glucose transport and glycolysis. However, different form of ß regulatory subunits dominated in stresses with regard to cell tolerance and glucose utilization. The Sip1 isoform was more necessary to the growth and glucose consumption in ethanol stress. The glucose uptake largely depended on the Sip2 isoform in high sugar and ethanol stresses. The Gal83 isoform only contributed inferior effect on the growth in ethanol stress. Therefore, redundancy and synergistic effect of ß subunits might occur in high glucose, ethanol, and heat stresses, but each subunit showed specificity under various stresses. CONCLUSIONS: This study enriches the understanding of the function of Snf1 protein kinase and provides an insight to breed multi-stress tolerant yeast strains.


Assuntos
Proteínas Serina-Treonina Quinases/fisiologia , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/enzimologia , Etanol/metabolismo , Glucose/metabolismo , Resposta ao Choque Térmico , Isoenzimas/fisiologia
10.
Anal Chem ; 91(21): 13658-13664, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31577422

RESUMO

The study of endocytosis, which encompasses diverse mechanisms in biology, requires the utilization of high axial resolution to monitor molecular behavior on both the cell surface and interior of the cell. We have designed a novel axially resolved fluorescence microscopic technique, termed variable-angle nanoplasmonic fluorescence microscopy. The proof-of-principle of this approach is achieved by selectively following the events in the vicinity of a cell membrane or in a cell. We use a 30 nm Au-coated semitransparent coverslip as the nanoplasmonic chip to achieve both surface plasmon resonance excitation and critical angle excitation by tuning the incident angles. This approach leads to improved axial resolution compared to total internal reflection fluorescence microscopy, which is a common imaging technique in cell biology. It offers a unique opportunity to semiquantitatively determine fluorophore axial distributions in the cell. Observing the epidermal growth factor receptor-mediated endocytosis in Caski cells clearly demonstrates the potential application of this new method for cell biology studies.


Assuntos
Endocitose , Microscopia de Fluorescência/métodos , Células Cultivadas , Corantes Fluorescentes/química , Humanos , Frações Subcelulares/metabolismo , Ressonância de Plasmônio de Superfície
11.
Int J Legal Med ; 133(3): 921-930, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30790037

RESUMO

Regressive dental changes appear to be suitable for age assessment in living adults. In 2012, Olze et al. showed that several criteria presented by Gustafson for extracted teeth can also be applied to orthopantomograms. The objective of this study was to test the applicability and reliability of this method in a Chinese population. For this purpose, 1300 orthopantomograms of 650 female and 650 male Chinese aged between 15 and 40 years were evaluated. The characteristics of secondary dentin formation, periodontal recession, attrition, and cementum apposition were reviewed in all the mandibular premolars. The sample was split into a training and test dataset. Based on the training set, the correlation of the individual characteristics with chronological age was studied with a stepwise multiple regression analysis, in which individual characteristics formed the independent variable. According to the results, the R values amounted to 0.80 to 0.83; the standard error of estimate was 4.29 to 4.75 years. By analyzing the test dataset, the accuracy of the present study, Olze's and Timme's formulas were determined by the difference between the estimated dental age (DA) and chronological age (CA). Taking both mean differences and mean absolute differences into account, the Chinese age estimation formula did not always perform better compared with Olze's and Timme's formulas for both males and females. It was concluded that this method can be used in Chinese individuals for age assessment. However, the applicability of the method is limited by the quality of the X-ray images, and the method should only be applied by experienced forensic odontologists.


Assuntos
Determinação da Idade pelos Dentes/métodos , Adolescente , Adulto , Povo Asiático , Dente Pré-Molar/diagnóstico por imagem , China , Cemento Dentário/diagnóstico por imagem , Dentina Secundária/diagnóstico por imagem , Feminino , Retração Gengival/classificação , Retração Gengival/diagnóstico por imagem , Humanos , Masculino , Radiografia Panorâmica , Análise de Regressão , Atrito Dentário/classificação , Atrito Dentário/diagnóstico por imagem , Adulto Jovem
12.
J Asian Nat Prod Res ; 21(2): 157-164, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29210285

RESUMO

Two new tetralone derivatives, named cyclopalosides A (1) and B (2), were isolated from the leaves of Cyclocarya paliurus by column chromatography on silica gel, reversed-phase C18 silica gel and preparative HPLC. Their chemical structures were established on the basis of extensive analyses of spectroscopic data. Their structural characteristic is tetralone glycoside with a caffeoyl unit. The antioxidant activities of compound 1 were evaluated by using hydroxyl, superoxide anion, and DPPH radical scavenging assay.


Assuntos
Juglandaceae/química , Folhas de Planta/química , Tetralonas/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo , Estrutura Molecular , Picratos , Tetralonas/química
13.
Molecules ; 24(19)2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557836

RESUMO

Coumarins are widely present in a variety of plants and have a variety of pharmacological activities. In this study, we isolated a coumarin compound from Microsorium fortunei (Moore) Ching; the compound was identified as esculetin by hydrogen and carbon spectroscopy. Its anti-hepatitis B virus (HBV) activity was investigated in vitro and in vivo. In the human hepatocellular liver carcinoma 2.2.15 cell line (HepG2.2.15) transfected with HBV, esculetin effecting inhibited the expression of the HBV antigens and HBV DNA in vitro. Esculetin inhibited the expression of Hepatitis B virus X (HBx) protein in a dose-dependent manner. In the ducklings infected with duck hepatitis B virus (DHBV), the levels of DHBV DNA, duck hepatitis B surface antigen (DHBsAg), duck hepatitis B e-antigen (DHBeAg), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) decreased significantly after esculetin treatment. Summing up the above, the results suggest that esculetin efficiently inhibits HBV replication both in vitro and in vivo, which provides an opportunity for further development of esculetin as antiviral drug.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Extratos Vegetais/farmacologia , Umbeliferonas/farmacologia , Animais , Antivirais/química , Antivirais/uso terapêutico , Biomarcadores , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , DNA Viral , Patos , Hepatite B/sangue , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Umbeliferonas/química , Umbeliferonas/uso terapêutico
14.
Int J Syst Evol Microbiol ; 68(10): 3125-3131, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30132753

RESUMO

Phylogenetic analysis was performed on a cellulose-producing strain, designated WE7T, isolated from contaminated coconut milk. The analysis utilized nearly complete 16S rRNA gene sequences, as well as concatenated partial sequences of the housekeeping genes dnaK, groEL and rpoB, and allowed identification of the strain as belonging to the genus Komagataeibacter. DNA-DNA correlation or average nucleotide identity analysis was performed between WE7T and its closest phylogenetic neighbours, and the resulting values were below the species level (<70 % and <95 %), suggesting that the strain represents a novel species in genus Komagataeibacter. Strain WE7T was coupled with Komagataeibacter species more tightly than with Gluconacetobacter species in a 16S rRNA gene sequence phylogenetic tree. Strain WE7T can be differentiated from closely related Komagataeibacter and Gluconacetobacter entanii species by the ability to grow on the carbon sources d-mannitol, sodium d-gluconate and glycerol, the ability to form acid by d-fructose, sucrose, d-mannitol, d-galactose and ethanol, and the ability to grow without acetic acid. The major fatty acid of WE7T is C18 : 1ω9c (52.3 %). The DNA G+C content of WE7T is 63.2 mol%. The name Komagataeibacter cocois sp. nov. is proposed, with the type strain WE7T (=CGMCC 1.15338T=JCM 31140T).


Assuntos
Acetobacteraceae/classificação , Cocos/microbiologia , Alimentos Fermentados/microbiologia , Microbiologia de Alimentos , Filogenia , Acetobacteraceae/genética , Acetobacteraceae/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Opt Express ; 24(22): A1349-A1359, 2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27828521

RESUMO

p-type inorganic hole transport materials of Li, Cu-codoped NiOx films were deposited using a simple solution-based process. The as-prepared films were used as hole selective contacts for lead halide perovskite solar cell. An enhanced power conversion efficiency of 14.53% has been achieved due to the improved electrical conductivity and optical transmittance of the Li, Cu-codoped NiOx electrode interlayer.

16.
Zhong Yao Cai ; 38(2): 215-20, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-26415392

RESUMO

OBJECTIVE: To study the impacts of lead (Pb) stress on the leaf photosynthetic pigment and the growth of Rabdosia rubescens,in order to provide a basis for planting area selection and growth regulation. METHODS: Taking chlorophyll a, chlorophyll b, carotenoids, growth rate, biomass and Pb content as the indexes, the Ramets hydroponic experiments at Pb concentration levels (135,270 and 540 mg/L) in the time(20, 35 and 50 d) were carried out. Photosynthetic pigment content was determined by spectrophotometer, and Pb mass fraction was detected with plasma emission spectrometer. RESULTS: There was uncertain effect on chlorophyll and carotenoid synthesis in different Pb concentrations in-early period (20 and 35 d). At the time of 50 d, the chlorophyll content was higher in the low-mid Pb concentrations, significantly lower in the high Pb concentration compared with the control group, and there were no significant differences on carotenoid contents in different Pb concentrations. CONCLUSION: Low-mid Pb concentrations can promote chlorophyll synthesis, and the bioaccumulation of high Pb concentration can inhibit the chlorophyll synthesis, and then restrict the growth of Rabdosia rubescens.


Assuntos
Carotenoides/química , Clorofila/química , Isodon/efeitos dos fármacos , Chumbo/farmacologia , Fotossíntese , Biomassa , Clorofila A , Isodon/crescimento & desenvolvimento , Folhas de Planta/química
17.
J Am Chem Soc ; 136(19): 6802-5, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24785106

RESUMO

We have demonstrated the proof-of-concept of a label-free biosensor based on emission induced by an extreme hot-spot plasmonic assembly. In this work, an ultrathin linking layer composed of cationic polymers and aptamers was fabricated to mediate the assembly of a silver nanoparticles (AgNPs)-dyes-gold film with a strongly coupled architecture through sensing a target protein. Generation of directional surface plasmon coupled emission (SPCE) was thus stimulated as a means of reporting biorecognition. Both the biomolecules and the nanoparticles were totally free of labeling, thereby ensuring the activity of biomolecules and allowing the use of freshly prepared metallic nanoparticles with large dimensions. This sensor smartly prevents the plasmonic assembly in the absence of targets, thus maintaining no signal through quenching fluorophores loaded onto a gold film. In the presence of targets, the ultrathin layer is activated to link NPs-film junctions. The small gap of the junction (no greater than 2 nm) and the large diameter of the nanoparticles (~100 nm) ensure that ultrastrong coupling is achieved to generate intense SPCE. A >500-fold enhancement of the signal was observed in the biosensing. This strategy provides a simple, reliable, and effective way to apply plasmonic nanostructures in the development of biosensing.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanoestruturas/química , Prata/química , Ressonância de Plasmônio de Superfície/instrumentação , Trombina/análise , Sequência de Bases , Desenho de Equipamento , Fluorescência , Corantes Fluorescentes/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Polímeros/química
18.
Zhongguo Zhong Yao Za Zhi ; 39(21): 4216-21, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25775796

RESUMO

The seeds of Rabdosia rubescens were as the materials to research the impacts of different lead (Pb2+) concentrations(0, 135, 270, 540, 1 080 mg x L(-1)) on seed germination and seedling growth. The results show that: Low concentration of lead had no obvious effect on early germination of the seed, the germination vigor and germination speed were lightly higher but not significantly differed at the level of Pb concentration 135 mg x L(-1) with control group; Mid-high concentration of Pb solution (270-1 080 mg x L(-1)) significantly inhibited the seed germination and seedling growth, which reduced the seed germination rate, germination vigor, germination index, embryo root length and shoot length, growth index with increasing of Pb concentrations. There was a inhibitory effect on embryo shoot length and root length at mid-high lead concentrations stress, and stronger inhibitory effect on root , which was more sensitive than shoot to Pb stress(P < 0.05). Pb bioaccumulation coefficient (BC) was 0.76-2.59, increased with concentration of Pb; Pb enrichment in seedling mainly caused the growth inhibition. The fitting model predictive analyses show, the critical concentration of Pb, which causes the germination rate and biomass fresh weight reducing 10%, is 195.18, 101.65 mg x L(-1).


Assuntos
Germinação/efeitos dos fármacos , Isodon/efeitos dos fármacos , Chumbo/toxicidade , Plântula/crescimento & desenvolvimento , Estresse Fisiológico , Isodon/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento
19.
Chemistry ; 19(31): 10107-10, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23780791

RESUMO

On the bright side: A solution-based strategy was developed for in situ synthesis and film deposition of Cu2ZnSnSe4 nanocrystal films (samples a-d). The obtained Cu2ZnSnSe4 nanocrystal films can be used as an effective counter-electrode (CE) material to replace Pt, and yield low-cost, high-efficiency dye-sensitized solar cells (DSSCs). The assembled solar cell devices exhibit an efficiency of 7.82 % under 1 sun irradiation (see figure).

20.
Artigo em Zh | MEDLINE | ID: mdl-24053963

RESUMO

OBJECTIVE: To investigate the effects of electromagnetic radiation on the physiological indices and immune function of operators. METHODS: The general conditions and electromagnetic radiation awareness rate of 205 operators under electromagnetic radiation were evaluated using a self-designed questionnaire. Physical examination, electrocardiography, and routine urine test were performed in these operators. Peripheral blood was collected from the operators under electromagnetic radiation for blood cell counting and biochemical testing, and their peripheral blood lymphocytes were cultured for determination of chromosomal aberrant frequency and micronucleus frequency. The data from these operators (exposure group) were compared with those of 95 ordinary individuals (control group). RESULTS: The chief complaint of giddiness, tiredness, dizziness, and amnesia showed significant differences between the exposure group and control group (P < 0.01), and the difference in headache became larger with an increase in working years. The awareness rate of electromagnetic radiation damage was significantly higher in the exposure group than in the control group. The difference in bradycardia was significant between the two groups (P <0.01), and the incidence was higher with longer working years. Significant differences between the two groups were also found in the numbers of individuals with elevated alanine aminotransferase, total bilirubin, and direct bilirubin (P < 0.01), populations with increased lymphocyte ratio and decreased neutrophil ratio (P < 0.01), populations with positive occult blood, urobilinogen, and bilirubin tests, and the number of individuals with increased micronucleus frequency of cultured peripheral blood lymphocytes (P < 0.01). In addition, the exposure group had significantly increased complement C3 and C4 (P < 0.01), significantly increased IgG (P < 0.05), and significantly decreased IgM (P < 0.01), as compared with the control group. CONCLUSION: Electromagnetic radiation may lead to the changes in physiological indices, genetic effects, and immune function and affect the health and immune function in operators. The adverse effects are increased as the working years increase. So it is important to strengthen occupational protection of operators under electromagnetic radiation.


Assuntos
Radiação Eletromagnética , Linfócitos/efeitos da radiação , Exposição Ocupacional/efeitos adversos , Adulto , Aberrações Cromossômicas/efeitos da radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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