Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros













Base de datos
Intervalo de año de publicación
1.
Nat Prod Res ; : 1-5, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38206882

RESUMEN

The volatile organic compounds (VOCs) of Rhizoma Acori Tatarinowii were extracted via steam distillation and then irradiated with 60Co-γ rays, in which doses of 60Co-γ 0, 5, and 10 kGy were selected to irradiate the VOCs. Finally, gas chromatography-ion mobility spectrometry (GC-IMS) was used to compare the differences between the VOCs, and then qualitatively analyse the components and contents of each part of the VOCs The results showed that under the three irradiation doses of 60Co-γ 0, 5 and 10 kGy, the VOCs of unirradiated and 5 kGy-irradiated samples were closer, and the samples irradiated at a 10 kGy dose were quite different from the other two components, meaning that when the calamus medicinal materials were sterilised by means of 60Co irradiation, the dose of 5 kGy was closer to the original compound content of the medicinal materials.

2.
Inorg Chem ; 62(19): 7186-7194, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37128761

RESUMEN

Hybrid lead halide perovskites have received extensive scientific attention owing to their great potential in the field of fluorescent displays and light-emitting diodes. Currently, most luminescent materials contain functional molecular and rare-earth metal ion parts. However, the mechanism of photoluminescence property in two-dimensional hybrid lead halide perovskites with different layered inorganic skeletons has been reported rarely. To better understand the effect of an inorganic skeleton on the fluorescence property, here, we report three organic-inorganic hybrid materials with different layered inorganic frameworks: (MACH)2·PbBr4 (Prv-1, MACH = cyclohexylmethylammonium), (2-MPQ)·PbBr4 (Prv-2, 2-MPQ = 2-methylpiperazinium), and (TMBA)4·Pb3Br10 (Prv-3, TMBA = N'N'N'-trimethylbenzylammonium). Among them, Prv-1 is a (100)-oriented perovskite, Prv-2 belongs to the (110)-oriented perovskite, and the inorganic framework of Prv-3 possesses [Pb3Br10] units. Interestingly, Prv-1 has a strong blue-violet fluorescence emission, while the luminescence effect of Prv-2 is very weak; notably, Prv-3 emits a charming bright-orange light. Meanwhile, results of theoretical computational studies also reveal that the electronic structure of all three compounds is highly dependent on structurally distorted [PbBr6] octahedra, and the frontier molecular orbital (FMO) analysis further suggests that HOMO and LUMO of Prv-3 are contributed by inorganic and organic components, respectively. In addition, all three materials belong to direct band gap semiconductors, and the band gaps are 2.79, 2.97, and 2.76 eV, respectively. Significantly, there are obvious differences in conduction bands. Based on the above analysis, the photoluminescence mechanism of three hybrid materials is explained from the electronic levels. Consequentially, this work might provide practical strategies and perspectives for exploring novel structure-related properties.

3.
Chem Sci ; 14(7): 1781-1786, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36819861

RESUMEN

Organic-inorganic halide perovskites (OIHPs) are very eye-catching due to their chemical tunability and rich physical properties such as ferroelectricity, magnetism, photovoltaic properties and photoluminescence. However, no nickel-based OIHP ferroelectrics have been reported so far. Here, we designed an ABX3 OIHP ferroelectric (3-pyrrolinium)NiCl3, where the 3-pyrrolinium cations are located on the voids surrounded by one-dimensional chains composed of NiCl6-face-sharing octahedra via hydrogen bonding interactions. Such a unique structure enables the (3-pyrrolinium)NiCl3 with a high spontaneous polarization (P s) of 5.8 µC cm-2 and a high Curie temperature (T c) of 428 K, realizing dramatic enhancement of 112 and 52 K compared to its isostructural (3-pyrrolinium)MCl3 (M = Cd, Mn). To our knowledge, remarkably, (3-pyrrolinium)NiCl3 should be the first case of nickel(ii)-based OIHP ferroelectric to date, and its T c of 428 K (35 K above that of BaTiO3) is the highest among all reported one-dimensional OIHP ferroelectrics. This work offers a new structural building block for enriching the family of OIHP structures and will inspire the further exploration of new nickel(ii)-based OIHP ferroelectrics.

4.
Chemistry ; 28(69): e202202533, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36082618

RESUMEN

Organic-inorganic Hybrid (OIH) materials for multifunctional switchable applications have attracted enormous attention in recent years due to their excellent optoelectronic properties and good structural tunability. However, it still remains challenging to fabricate one simple OIH compound with multi-functionals properties, such as dielectric switching, thermochromic properties, semiconductor characteristics and ferroelasticity. Under this context, we successfully synthesized [2-(2-fluorophenyl)ethan-1- ammonium]2 SnBr6 (compound 1), which has a higher phase transition temperature of 427.7 K. Additionally, it exhibits a semiconducting property with an indirect band gap of 2.36 eV. Combining ferroelastic, narrow band gap, thermochromic, and dielectric properties, compound 1 can be considered as a rarely reported multi-functional ferroelastic material, which is expected to give inspiration for broadening the applications in the smart devices field.


Asunto(s)
Semiconductores , Transición de Fase
5.
Dalton Trans ; 51(5): 2005-2011, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35029614

RESUMEN

Multifunctional switching materials show great potential for applications in sensors, smart switches, and other fields due to their ability to integrate different physical channels in one single device. However, multifunctional responsive materials with multiple switching and luminescence properties have rarely been reported. Here, we report three organic-inorganic hybrids: [TMAA]2[CoCl4] (compound 1), [TMAA]2[CdBr4] (compound 2) and [TMAA]2[MnCl4] (compound 3). Compound 1 and compound 2 undergo two reversible phase transitions at high temperature (328.95/359.25 K and 350.45/393.15 K, respectively). Since the inorganic skeleton has a strong influence on the luminescence properties of such structured substances, Cd and Co were replaced with Mn, after which compound 3 was obtained as expected. The above strategy triggered bright green luminescence with a quantum yield of 35.19%, and significantly increased the phase transition temperature of compound 3 to above 400 K. The above results show that the regulation of the inorganic skeleton provides a new strategy for researchers to develop dual phase change/luminous materials.

6.
Huan Jing Ke Xue ; 38(9): 3979-3986, 2017 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-29965282

RESUMEN

The thin layered graphitic carbon nitride (g-C3N4) was prepared by the thermal polymerization process with urea as the precursor. The layered heterostructure of graphitic carbon nitride-bismuth oxyiodide (g-C3N4/BiOI) was constructed by the in-situ synthetization of bismuth oxyiodide (BiOI) on the surface of the thin layered g-C3N4. The morphology, specific surface area, crystal structure, molecular structure, light absorption properties, and surface properties were characterized by TEM, BET, XRD, FT-IR, UV-Vis DRS, and XPS, respectively. The disinfection performance of the synthesized catalysts under visible light irradiation was investigated. The antibacterial mechanism of g-C3N4/BiOI in the photocatalytic process was further revealed by the capture of sacrificial agents. The results indicate that the prepared sample has a layered heterojunction structure with a specific surface area of 63 m2·g-1 and its light absorption side can obtain 600 nm. The results of the photocatalytic activity test indicate that g-C3N4/BiOI can kill bacteria within 4 h, which is significantly higher than that of g-C3N4 and BiOI. The main active species of g-C3N4/BiOI in the photocatalytic process can be attributed to the photogenerated holes.


Asunto(s)
Antibacterianos/química , Bismuto/química , Grafito/química , Nitrilos/química
7.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2477-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-25865497

RESUMEN

The complete chloroplast sequence of the Anoectochilus roxburghii, a popular traditional Chinese medicine for the treatment of cancer, was determined in this study. The chloroplast genome (cpDNA)^ was 152,802 bp in length, containing a pair of inverted repeats of 52,728 bp separated by a large single-copy region and a small single-copy region of 82,641 bp and 17,433 bp, respectively. The chloroplast genome encodes 116 predicted functional genes, including 81 protein-coding genes, four ribosomal RNA genes, and 31 transfer RNA genes, 25 of which are duplicated in the inverted repeat regions. The cpDNA is GC-rich (36.9%).


Asunto(s)
Genoma del Cloroplasto , Orchidaceae/clasificación , Orchidaceae/genética , Composición de Base , Biología Computacional , Genes del Cloroplasto , Tamaño del Genoma , Sistemas de Lectura Abierta , Filogenia , Análisis de Secuencia de ADN , Secuenciación Completa del Genoma
8.
Bing Du Xue Bao ; 30(6): 661-7, 2014 Nov.
Artículo en Chino | MEDLINE | ID: mdl-25868281

RESUMEN

NS2 and NS3 are two post-transcriptional gene silencing suppressors that are encoded by Rice stripe virus. Gene silencing suppressors are always related to the pathogenicity of viruses. In this study, the cDNA of NS2 and NS3 were recombined by overlapping PCR assays, ligated to the RNAi vector, and inserted into the PXQ expression vector using Pst I; the expressed vector was transferred into calluses induced from seeds of the japonica rice cultivar, 'Nipponbare', using an Agrobacterium-mediated method. Thirty-one T0 transgenic plants were selected by G418 screening. PCR and southern blot analyses confirmed that the target gene was transformed into transgenic rice successfully, and different transgenic plants contained various copies of the gene. The disease resistance assay revealed that T0 transgenic rice had a delayed onset of RSV for approximately 10-20 d, and the accumulation of virus in the transgenic plants was reduced by 30%-50%. This was related to the delayed onset of disease.


Asunto(s)
Oryza/genética , Oryza/inmunología , Enfermedades de las Plantas/virología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/inmunología , Interferencia de ARN , Tenuivirus/genética , Proteínas no Estructurales Virales/genética , Resistencia a la Enfermedad , Oryza/virología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Plantas Modificadas Genéticamente/virología , Tenuivirus/inmunología , Proteínas no Estructurales Virales/inmunología
9.
Chin J Nat Med ; 11(5): 572-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24359786

RESUMEN

AIM: To establish an LC-MS/MS method for determination of isorhamnetin-3-O-neohesperidoside and investigate its application on pharmacokinetic study in rats. METHODS: Eight rats were given 5 mg·kg(-1) isorhamnetin-3-O-neohesperidoside after intravenous administration. A highly sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of isorhamnetin-3-O-neohesperidosidein rat plasma using rutin as internal standard. The analytes and rutin (internal standard) were extracted with methanol followed by a rapid isocratic elution with 10 mmol·L(-1) ammonium acetate buffer/methanol (20 : 80, V/V) on a C18 column (150 mm × 2.1 mm, I.D., 5 µm) and subsequent analysis by mass spectrometry in the multi-eaction-monitoring mode. RESULTS: The assays were linear over the concentration range of 0.01-10 µg·mL(-1) for isorhamnetin-3-O-neohesperidosidein rat plasma. The lower limit of quantifications for isorhamnetin-3-O-neohesperidoside was 0.01 µg·mL(-1). CONCLUSION: The validated method is successfully applied to determine the plasma concentrations of isorhamnetin-3-O-neohesperidosidein in rats.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/farmacocinética , Espectrometría de Masas en Tándem/métodos , Typhaceae/química , Animales , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/análisis , Flavonoles/administración & dosificación , Flavonoles/sangre , Flavonoles/farmacocinética , Polen/química , Ratas , Espectrometría de Masa por Ionización de Electrospray/métodos
10.
Arch Virol ; 157(9): 1821-4, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22622432

RESUMEN

The complete genome sequence of a Chinese narcissus isolate of narcissus late season yellows virus from Zhangzhou, China (NLSYV-ZZ), was determined to be 9,651 nucleotides in length, excluding the 3'-terminal poly (A) tail, by amplification and sequencing of virus RNA. The viral genome contains a single long open reading frame of 9,315 nucleotides encoding a polyprotein of 3,105 amino acids. The polyprotein was predicted to be cleaved into ten mature proteins by three viral proteases. Complete genome sequence comparison and phylogenetic analysis indicated that NLSYV-ZZ was most closely related to narcissus yellow stripe virus (NYSV), which was also isolated from narcissus. These viruses shared 69.9 % identity in their complete nucleotide sequences and 77.0 % identity in their polyprotein amino acid sequences.


Asunto(s)
Genoma Viral , Narcissus/virología , Enfermedades de las Plantas/virología , Potyvirus/genética , ARN Viral/genética , Análisis de Secuencia de ADN , China , Análisis por Conglomerados , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Poliproteínas/genética , Potyvirus/aislamiento & purificación , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/genética
11.
Aging Male ; 14(1): 27-32, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21067315

RESUMEN

BACKGROUND: Accumulating evidence implicates leukocyte telomere length (LTL) shortening as a potential risk predictor for cardiovascular disease. Arterial stiffness chronicles the cumulative burden of cardiovascular disease risk factors. Therefore, the capacity of LTL to predict arterial stiffness was examined. METHODS: A total of 275 unrelated Chinese males: 163 patients with coronary artery disease (CAD) and 112 healthy controls, 40-73 years of age were included in this study. The relative telomere length of leukocytes was determined by a real-time fluorescence quantitative polymerase chain reaction (PCR). Large artery stiffness was measured with carotid-femoral pulse wave velocity (PWV). RESULTS: The relative telomere length (T/S) ratio was significantly shorter in patients with CAD (0.79 +/- 0.26) than in control subjects (1.08 +/- 0.22) (p<0.001). The correlation between LTL and PWV in patients with CAD was stronger than that in the controls (r= -0.467, r(2)=0.227, p<0.001 for patients with CAD versus r= -0.223; r(2)=0.050; p=0.018 for controls). The log(e)-transformed T/S ratio was inversely correlated with age (r= -0.345; p<0.001), PWV (r= -0.326; p<0.001) and C-reactive protein ( r= -0.133; p=0.027). CONCLUSIONS: The data show an association of leukocyte telomere length shortening with increased arterial stiffness and cardiovascular burden, suggesting that telomere length is a biomarker of large artery elasticity and CAD. Further studies are warranted to study the role of LTL dynamics in the pathogenesis of atherosclerosis.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Vasos Coronarios/patología , Telómero/genética , Adulto , Anciano , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Vasos Coronarios/diagnóstico por imagen , Elasticidad , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Estrés Oxidativo , Valores de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Ultrasonografía
12.
Virol Sin ; 25(6): 401-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21221918

RESUMEN

To obtain the P8 protein of Rice gall dwarf virus (RGDV) with biological activity, its outer coat protein gene S8 was expressed in Spodoptera frugiperda (Sf9) insect cells using the baculovirus expression system. The S8 gene was subcloned into the pFastBac™1 vector, to produce the recombinant baculovirus transfer vector pFB-S8. After transformation, pFB-S8 was introduced into the competent cells (E. coli DH10Bac) containing a shuttle vector, Bacmid, generating the recombinant bacmid rbpFB-S8. After being infected by recombinant baculovirus rvpFB-S8 at different multiplicities of infection, Sf9 cells were collected at different times and analyzed by SDS-PAGE, Western blotting and immunofluorescence microscopy. The expression level of the P8 protein was highest between 48-72 h after transfection of Sf9 cells. Immunofluorescence microscopy showed that P8 protein of RGDV formed punctate structures in the cytoplasm of Sf9 cells.


Asunto(s)
Proteínas de la Cápside/biosíntesis , Proteínas de la Cápside/genética , Expresión Génica , Reoviridae/genética , Animales , Baculoviridae/genética , Western Blotting , Línea Celular , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Vectores Genéticos , Microscopía Fluorescente , Oryza , Spodoptera
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA