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1.
J Am Chem Soc ; 146(17): 11657-11668, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38641862

RESUMEN

All protein-directed syntheses of metal nanoclusters (NCs) and nanoparticles (NPs) have attracted considerable attention because protein scaffolds provide a unique metal coordination environment and can adjust the shape and morphology of NCs and NPs. However, the detailed formation mechanisms of NCs or NPs directed by protein templates remain unclear. In this study, by taking advantage of the ferritin nanocage as a biotemplate to monitor the growth of Fe-O NCs as a function of time, we synthesized a series of iron NCs with different sizes and shapes and subsequently solved their corresponding three-dimensional atomic-scale structures by X-ray protein crystallography and cryo-electron microscopy. The time-dependent structure analyses revealed the growth process of these Fe-O NCs with the 4-fold channel of ferritin as nucleation sites. To our knowledge, the newly biosynthesized Fe35O23Glu12 represents the largest Fe-O NCs with a definite atomic structure. This study contributes to our understanding of the formation mechanism of iron NCs and provides an effective method for metal NC synthesis.


Asunto(s)
Ferritinas , Tamaño de la Partícula , Ferritinas/química , Nanopartículas del Metal/química , Hierro/química , Modelos Moleculares , Cristalografía por Rayos X , Compuestos Férricos/química
2.
Yi Chuan ; 46(4): 333-345, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38632095

RESUMEN

China has a high dependence on soybean imports, yield increase at a faster rate is an urgent problem that need to be solved at present. The application of heterosis is one of the effective ways to significantly increase crop yield. In recent years, the development of an intelligent male sterility system based on recessive nuclear sterile genes has provided a potential solution for rapidly harnessing the heterosis in soybean. However, research on male sterility genes in soybean has been lagged behind. Based on transcriptome data of soybean floral organs in our research group, a soybean stamen-preferentially expressed gene GmFLA22a was identified. It encodes a fasciclin-like arabinogalactan protein with the FAS1 domain, and subcellular localization studies revealed that it may play roles in the endoplasmic reticulum. Take advantage of the gene editing technology, the Gmfla22a mutant was generated in this study. However, there was a significant reduction in the seed-setting rate in the mutant plants at the reproductive growth stage. The pollen viability and germination rate of Gmfla22a mutant plants showed no apparent abnormalities. Histological staining demonstrated that the release of pollen grains in the mutant plants was delayed and incomplete, which may due to the locule wall thickening in the anther development. This could be the reason of the reduced seed-setting rate in Gmfla22a mutants. In summary, our study has preliminarily revealed that GmFLA22a may be involved in regulating soybean male fertility. It provides crucial genetic materials for further uncovering its molecular function and gene resources and theoretical basis for the utilization of heterosis in soybean.


Asunto(s)
Glycine max , Infertilidad Masculina , Masculino , Humanos , Plantas , Polen/genética , Fertilidad , Infertilidad Vegetal/genética , Regulación de la Expresión Génica de las Plantas
3.
Eat Weight Disord ; 28(1): 63, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37526777

RESUMEN

Previous observational studies have investigated the relationship between obesity and the biliary tract and pancreas. The causality, however, is still to be confirmed. This study was designed to explore the causality between obesity which included body mass index(BMI), circumference (WC), hip circumference (HC) and waist-to-hip ratio (WHR), and pancreatobiliary diseases with a Two-Sample Mendelian Randomization(MR) analysis. single-nucleotide polymorphisms used in our study were derived from genome-wide association studies (GWAS). The inverse variance weighted was the dominated method to evaluate the causality. The heterogeneity was validated by Cochran's Q test. The pleiotropy was validated by MR-Egger regression and MR-PRESSO. The stability and reliability of the results were illustrated by the 'leave-one-out'sensitivity analysis. The MR results explored positive causal effects of BMI (OR: 1.021; 95% CI: from 1.016 to 1.027; P = 4.25 × 10-15) and WC (OR: 1.021; 95% CI: from 1.015 to 1.028; P = 1.65 × 10-10) on pancreatobiliary diseases. However, no causality existed between HC, WHR and pancreatobiliary diseases. This study reminded that general obesity and abdominal obesity required weight loss to prevent pancreatic biliary disease.


Asunto(s)
Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Humanos , Reproducibilidad de los Resultados , Obesidad/genética , Obesidad Abdominal , Polimorfismo de Nucleótido Simple
4.
Inorg Chem ; 60(12): 8826-8837, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34060309

RESUMEN

How to deliver nitric oxide (NO) to a physiological target and control its release quantitatively is a key issue for biomedical applications. Here, a water-soluble nitrosylruthenium complex, [(CH3)4N][RuCl3(5cqn)(NO)] (H5cqn = 5-chloro-8-quinoline), was synthesized, and its structure was confirmed with 1H NMR and X-ray crystal diffraction. Photoinduced NO release was investigated with time-resolved Fourier transform infrared and electron paramagnetic resonance (EPR) spectroscopies. The binding constant of the [RuCl3(5cqn)(NO)]- complex with human serum albumin (HSA) was determined by fluorescence spectroscopy, and the binding mode was identified by X-ray crystallography of the HSA and Ru-NO complex adduct. The crystal structure reveals that two molecules of the Ru-NO complex are located in the subdomain IB, which is one of the major drug binding regions of HSA. The chemical structures of the Ru complexes were [RuCl3(5cqn)(NO)]- and [RuCl3(Glycerin)NO]-, in which the electron densities for all ligands to Ru are unambiguously identified. EPR spin-trapping data showed that photoirradiation triggered NO radical generation from the HSA complex adduct. Moreover, the near-infrared image of exogenous NO from the nitrosylruthenium complex in living cells was observed using a NO-selective fluorescent probe. This study provides a strategy to design an appropriate delivery system to transport NO and metallodrugs in vivo for potential applications.


Asunto(s)
Complejos de Coordinación/metabolismo , Óxido Nítrico/metabolismo , Compuestos de Rutenio/metabolismo , Albúmina Sérica Humana/metabolismo , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Cristalografía por Rayos X , Colorantes Fluorescentes/química , Células HeLa , Humanos , Modelos Moleculares , Estructura Molecular , Óxido Nítrico/química , Imagen Óptica , Procesos Fotoquímicos , Compuestos de Rutenio/química , Albúmina Sérica Humana/química , Células Tumorales Cultivadas
5.
Molecules ; 26(9)2021 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-33925453

RESUMEN

Two light-activated NO donors [RuCl(qn)(Lbpy)(NO)]X with 8-hydroxyquinoline (qn) and 2,2'-bipyridine derivatives (Lbpy) as co-ligands were synthesized (Lbpy1 = 4,4'-dicarboxyl-2,2'-dipyridine, X = Cl- and Lbpy2 = 4,4'-dimethoxycarbonyl-2,2'-dipyridine, X = NO3-), and characterized using ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (1H NMR), elemental analysis and electrospray ionization mass spectrometry (ESI-MS) spectra. The [RuCl(qn)(Lbpy2)(NO)]NO3 complex was crystallized and exhibited distorted octahedral geometry, in which the Ru-N(O) bond length was 1.752(6) Å and the Ru-N-O angle was 177.6(6)°. Time-resolved FT-IR and electron paramagnetic resonance (EPR) spectra were used to confirm the photoactivated NO release of the complexes. The binding constant (Kb) of two complexes with human serum albumin (HSA) and DNA were quantitatively evaluated using fluorescence spectroscopy, Ru-Lbpy1 (Kb~106 with HSA and ~104 with DNA) had higher affinity than Ru-Lbpy2. The interactions between the complexes and HSA were investigated using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and EPR spectra. HSA can be used as a carrier to facilitate the release of NO from the complexes upon photoirradiation. The confocal imaging of photo-induced NO release in living cells was successfully observed with a fluorescent NO probe. Moreover, the photocleavage of pBR322 DNA for the complexes and the effect of different Lbpy substituted groups in the complexes on their reactivity were analyzed.


Asunto(s)
Complejos de Coordinación/química , Sustancias Macromoleculares/química , Rutenio/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/aislamiento & purificación , Complejos de Coordinación/farmacología , ADN/química , ADN/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Ligandos , Sustancias Macromoleculares/ultraestructura , Óxido Nítrico/biosíntesis , Óxido Nítrico/química , Rutenio/farmacología , Albúmina Sérica Humana/química , Espectroscopía Infrarroja por Transformada de Fourier
6.
Int J Mol Sci ; 21(14)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708160

RESUMEN

Psm ES4326/AvrRpt2 (AvrRpt2) was widely used as the reaction system of hypersensitive response (HR) in Arabidopsis. The study showed that in npr1 (GFP-ATG8a), AvrRpt2 was more effective at inducing the production of autophagosome and autophagy flux than that in GFP-ATG8a. The mRNA expression of ATG1, ATG6 and ATG8a were more in npr1 during the early HR. Based on transcriptome data analysis, enhanced disease susceptibility 1 (EDS1) was up-regulated in wild-type (WT) but was not induced in atg4a4b (ATG4 deletion mutant) during AvrRpt2 infection. Compared with WT, atg4a4b had higher expression of salicylic acid glucosyltransferase 1 (SGT1) and isochorismate synthase 1 (ICS1); but less salicylic acid (SA) in normal condition and the same level of free SA during AvrRpt2 infection. These results suggested that the consumption of free SA should be occurred in atg4a4b. AvrRpt2 may trigger the activation of Toll/Interleukin-1 receptor (TIR)-nucleotide binding site (NB)-leucine rich repeat (LRR)-TIR-NB-LRR-to induce autophagy via EDS1, which was inhibited by nonexpressor of PR genes 1 (NPR1). Moreover, high expression of NPR3 in atg4a4b may accelerate the degradation of NPR1 during AvrRpt2 infection.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Relacionadas con la Autofagia/metabolismo , Autofagia/inmunología , Proteínas Bacterianas/inmunología , Proteasas de Cisteína/metabolismo , Proteínas de Unión al ADN/metabolismo , Pseudomonas syringae/metabolismo , Ácido Salicílico/metabolismo , Arabidopsis/genética , Arabidopsis/inmunología , Arabidopsis/microbiología , Proteínas de Arabidopsis/genética , Autofagia/genética , Familia de las Proteínas 8 Relacionadas con la Autofagia/genética , Familia de las Proteínas 8 Relacionadas con la Autofagia/metabolismo , Proteínas Relacionadas con la Autofagia/genética , Proteínas Bacterianas/metabolismo , Beclina-1/genética , Beclina-1/metabolismo , Proteasas de Cisteína/genética , Proteínas de Unión al ADN/genética , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Transferasas Intramoleculares/genética , Transferasas Intramoleculares/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Plantas Modificadas Genéticamente , Pseudomonas syringae/patogenicidad , RNA-Seq
7.
Sensors (Basel) ; 17(11)2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29140284

RESUMEN

Static fatigue behavior is the main failure mode of optical fibers applied in sensors. In this paper, a computational framework based on continuum damage mechanics (CDM) is presented to calculate the crack propagation process and failure time of optical fibers subjected to static bending and tensile loads. For this purpose, the static fatigue crack propagation in the glass core of the optical fiber is studied. Combining a finite element method (FEM), we use the continuum damage mechanics for the glass core to calculate the crack propagation path and corresponding failure time. In addition, three factors including bending radius, tensile force and optical fiber diameter are investigated to find their impacts on the crack propagation process and failure time of the optical fiber under concerned situations. Finally, experiments are conducted and the results verify the correctness of the simulation calculation. It is believed that the proposed method could give a straightforward description of the crack propagation path in the inner glass core. Additionally, the predicted crack propagation time of the optical fiber with different factors can provide effective suggestions for improving the long-term usage of optical fibers.

8.
Cancer Manag Res ; 16: 593-602, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38855331

RESUMEN

Background: Regorafenib, a novel multikinase inhibitor, has been approved by the US Food and Drug Administration as a standard treatment choice for metastatic colorectal cancer (mCRC). Nonetheless, its substantial cost places a significant burden on social health resources and patients. However, the cost-effectiveness (CE) of regorafenib compared to other third-line therapies is still undetermined. Objective: This study aims to assess the CE of regorafenib compared to other third-line therapies for the treatment of mCRC. Methods: We conducted a comprehensive literature search in PubMed, Medline, Scopus, Embase, Cochrane Library, as well as nine other databases to identify relevant studies published up to October 2023, focusing on patients with mCRC and examining the cost-effectiveness of regorafenib. Following the screening and extraction of pertinent data, the study quality was assessed using the Quality of Health Economic Studies (QHES) checklist. Results: The literature search yielded 751 records, and after applying the inclusion criteria, 13 studies from 7 different countries were included. Of these, 7 studies evaluated the cost-effectiveness of regorafenib compared to trifluridine/tipiracil (TAS-102), 3 studies compared regorafenib with best supportive care (BSC), and 3 studies compared regorafenib with fruquintinib, serplulimab, and regorafenib dose optimization (ReDo).The quality of the included studies was high with an average QHES scores of 85.62. Regorafenib standard dose proves to be less cost-effective than alternative third-line therapies. Implementing a dose optimization strategy could potentially rectify this disparity and enhance the cost-effectiveness of regorafenib. Conclusion: The use of the standard dose of regorafenib is generally regarded as not cost-effective when compared to other third-line therapies for patients with mCRC. However, implementing a dose-escalation strategy may enhance regorafenib's cost-effectiveness. Consequently, significant price reductions or optimizing the dose of regorafenib are required to achieve cost-effectiveness.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124603, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38878720

RESUMEN

Iron-sulfur cluster conversion and nitrosyl modification are involved in regulating their functions and play critical roles in signaling for biological systems. Hereby, the photo-induced dynamic process of (Me4N)2[Fe2S2(NO)4] was monitored using time-resolved electron paramagnetic resonance (EPR) spectra, MS spectra and cellular imaging methods. Photo-irradiation and the solvent affect the reaction rates and products. Spectroscopic and kinetic studies have shown that the process involves at least three intermediates: spin-trapped NO free radical species with a gav at 2.040, and two other iron nitrosyl species, dinitrosyl iron units (DNICs) and mononitrosyl iron units (MNICs) with gav values at 2.031 and 2.024, respectively. Moreover, the [Fe2S2(NO)4]2- cluster could bind with ferritin and decompose gradually, and a binding state of dinitrosyl iron coordinated with Cys102 of the recombinant human heavy chain ferritin (rHuHF) was finally formed. This study provides insight into the photodynamic mechanism of nitrosyl iron - sulfur clusters to improve the understanding of physiological activity.

10.
Metallomics ; 16(2)2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38263542

RESUMEN

Four Ru(II)-centered isomeric complexes [RuCl(5cqn)(Val)(NO)] (1-4) were synthesized with 5cqn (5-chloro-8-hydroxyquinoline) and chiral Val (Val = L- or D-valine) as co-ligand, and their structures were confirmed using the X-ray diffraction method. The cytotoxicity and photodynamic activity of the isomeric complexes and their human serum albumin (HSA) complex adducts were evaluated. Both the isomeric complexes and their HSA complex adducts significantly affected HeLa cell proliferation, with an IC50 value in the range of 0.3-0.5 µM. The photo-controlled release of nitric oxide (NO) in solution was confirmed using time-resolved Fourier transform infrared and electron paramagnetic resonance spectroscopy techniques. Furthermore, photoinduced NO release in living cells was observed using a selective fluorescent probe for NO. Moreover, the binding constants (Kb) of the complexes with HSA were calculated to be 0.17-1.98 × 104 M-1 and the average number of binding sites (n) was found to be close to 1, it can serve as a crucial carrier for delivering metal complexes. The crystal structure of the HSA complex adduct revealed that one [RuCl(H2O)(NO)(Val)]+ molecule binds to a pocket in domain I. This study provides insight into possible mechanism of metabolism and potential applications for nitrosylruthenium complexes.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Humanos , Antineoplásicos/farmacología , Óxido Nítrico , Albúmina Sérica Humana/metabolismo , Células HeLa , Sitios de Unión , Complejos de Coordinación/farmacología , Complejos de Coordinación/química
11.
Int J Biol Macromol ; 243: 125009, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37245757

RESUMEN

Three isomeric nitrosylruthenium complexes [RuNO(Qn)(PZA)Cl] (P1, P2, and P3) with bioactive small molecules 8-hydroxyquinoline (Qn) and pyrazinamide (PZA) as co-ligands were synthesized, and their crystal structures were determined using X-ray diffraction technique. The cellular toxicity of the isomeric complexes was compared to understand the effects of the geometries on the biological activity of the complexes. Both the complexes and the human serum albumin (HSA) complex adducts affected the extent of proliferation of HeLa cells (IC50: 0.77-1.45 µM). P2 showed prominent activity-induced cell apoptosis and arrested cell cycles at the G1 phase. The binding constants (Kb) of the complex with calf thymus DNA (CT-DNA) and HSA were quantitatively evaluated using fluorescence spectroscopy in the range of 0.17-1.56 × 104 M-1 and 0.88-3.21 × 105 M-1, respectively. The average binding site (n) number was close to 1. Moreover, the structure of HSA and the P2 complex adduct solved at the resolution of 2.48 Å revealed that one PZA-coordinated nitrosylruthenium complex bound at the subdomain I of HSA via a noncoordinative bond. HSA could serve as a potential nano-delivery system. This study provides a framework for the rational design of metal-based drugs.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Humanos , Células HeLa , Ligandos , Unión Proteica , Antineoplásicos/farmacología , Albúmina Sérica Humana/química , Complejos de Coordinación/química
12.
Risk Manag Healthc Policy ; 16: 347-356, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36923494

RESUMEN

Purpose: Quality control circle (QCC) has acquired success in many fields in healthcare industry as a process management tool, whereas its efficacy in surgical antimicrobial prophylaxis (SAP) remains unknown. This study aimed to implement QCC interventions to improve the appropriateness of SAP. Methods: A QCC activity team was established to grasp the current situation of SAP in clean surgery procedure, set target, formulate corresponding countermeasures and implement and review them in stages. The plan-do-check-act (PDCA) method was cyclically applied. Results: The appropriateness of antibiotic prophylaxis before (January to December 2020) and after (January to December 2021) the implementation of QCC activities were evaluated based on relevant international and Chinese SAP guidelines. The overall SAP appropriateness was significantly improved from 68.72% before QCC to 93.7% post QCC implementation (P<0.01). A significant improvement (P<0.05) was also determined for each category: selection (from 78.82% to 96.06%), duration (from 90.15% to 96.46%), indication (from 94.09% to 97.64%), timing of first dose (from 96.55% to 99.21%), antimicrobial usage (from 96.8% to 99.41%), re-dosing of antimicrobial (from 96.55% to 99.21%). Conclusion: Implementation of a QCC program can optimize the use of antibiotics and improve the appropriateness of SAP and is of practical importance to their standardization.

13.
Front Plant Sci ; 14: 1069551, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36818831

RESUMEN

Introduction: Extreme weather has occurred more frequently in recent decades, which results in more frequent drought disasters in the maize growing season. Severe drought often decreases remarkably plant growth and yield of maize, and even reduces significantly the quality of maize production, especially for waxy maize. Results: To study the changes in plant growth, fresh ear yield, and fresh grain quality of waxy maize under water deficits occurring at different growth stages, and further strengthen the field water management of waxy maize, water deficit experiments were carried out under a rain shelter in 2019 and 2020. Water deficit treatments were imposed respectively at the V6-VT (DV6-VT), VT-R2 (DVT-R2), and R2-R3 (DR2-R3) stages of waxy maize, and treatment with non-water deficit in the whole growing season was taken as the control (CK). The lower limit of soil water content was 50% of field capacity for a water deficit period and 65% of field capacity for a non-water deficit period. Results: In this study, water deficits imposed at V6-VT and VT-R2 stages decreased plant growth rate and leaf gas exchange parameters, accelerated leaf senescence, and limited ear growth of waxy maize, which resulted in 11.6% and 23.1% decreases in grains per ear, 19.4% and 7.3% declines in 100-grain weight, 20.3% and 14.2% losses in fresh ear yield in 2019 and 2020 growing seasons, respectively, while water deficit at R2-R3 stage had no significant effect on ear traits and fresh ear yield, but the fresh ear yield with husk of DR2-R3 decreased by 9.1% (P<0.05). The obvious water deficit imposed at the V6-VT and VT-R2 stages also lowered grain quality. Water deficits at the V6-VT and VT-R2 stages led to accelerated maturity, resulting in increased total protein, starch, and lysine content in grains at the R3 stage and decreased soluble sugar content. Principal component analysis revealed that when water deficits occurred in the waxy maize growing season, they firstly altered maize physiological processes, then affected ear characteristics and yield, and finally resulted in significant grain quality changes. In conclusion, a water deficit during V6-VT and VT-R2 not only reduced fresh ear yield but also adversely affected grain quality. However, water deficit during R2-R3 had little effect on total protein, starch, and soluble sugar content,but increased obviously lysine content. Discussion: The above results suggested that avoiding serious water deficits at the V6-VT and VT-R2 stages of waxy maize while imposing a slight water deficit at the R2-R3 stage has not only little effects on fresh ear yield but also a remarkable improvement in grain quality.

14.
Sci China Life Sci ; 64(9): 1533-1545, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34236584

RESUMEN

Male sterility is an essential trait in hybrid seed production, especially for monoclinous and autogamous food crops. Soybean male-sterile ms1 mutant has been known for more than 50 years and could be instrumental in making hybrid seeds. However, the gene responsible for the male-sterile phenotype has remained unknown. Here, we report the map-based cloning and characterization of the MS1 gene in soybean. MS1 encodes a kinesin protein and localizes to the nucleus, where it is required for the male meiotic cytokinesis after telophase II. We further substantiated that MS1 colocalizes with microtubules and is essential for cell plate formation in soybean male gametogenesis through immunostaining. Both ms1 and CRISPR/Cas9 knockout mutants show complete male sterility but are otherwise phenotypically normal, making them perfect tools for producing hybrid seeds. The identification of MS1 has the practical potential for assembling the sterility system and speeding up hybrid soybean breeding.


Asunto(s)
Genes de Plantas , Glycine max/genética , Infertilidad Vegetal/genética , Proteínas de Plantas/genética , Semillas/genética , Sistemas CRISPR-Cas , Hibridación Genética , Fenotipo , Fitomejoramiento
15.
RSC Adv ; 10(33): 19300-19308, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35515443

RESUMEN

In recent years, gold nanoparticles (AuNPs) have been widely used as gene silencing agents and therapeutics for treatment of cancers due to their high transfection efficiency and lack of cytotoxicity, but their roles in gene silencing in plants have not yet been reported. Here, we report synthesis of AuNPs-branched polyethylenimine and its integration with the small interfering RNAs (siRNA) of NPR1 to form a AuNPs-siRNA NPR1 compound. Our results showed that AuNPs-siRNA NPR1 was capable of infiltrating into Arabidopsis cells. AuNPs-siRNA NPR1 silenced 80% of the NPR1 gene in Arabidopsis. Bacteriostatic and ion leakage experiments suggest that the NPR1 gene in Arabidopsis leaves was silenced by AuNPs-siRNA NPR1 . In Columbia-0 plants, compared with the control group treated with buffer solution, the AuNPs-siRNA NPR1 treatment significantly increased the number of colonies and cell death, and the leaves turned yellow, similar to the phenotype of the npr1 leaves. These results indicated this AuNPs-siRNA NPR1 silencing the NPR1 gene method is simple, effective and quick (3 days), and a powerful tool to study gene functions in plants.

16.
Anal Bioanal Chem ; 392(5): 1003-10, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18758761

RESUMEN

Microemulsion electrokinetic chromatography (MEEKC) has been developed for fingerprint analysis of resina draconis, a substitute for sanguis draconis in the Chinese market. The microemulsion as the running buffer was made up of 3.3% (w/v) sodium dodecyl sulfate (SDS), 6.6% (w/v) n-butanol, 0.8% (w/v) n-octane, and 10 mmol/L sodium tetraborate buffer (pH 9.2), which was also used as the solvent for ultrasonic extraction of both water- and fat-soluble compounds in the traditional Chinese medicine samples. Four batches of resina draconis obtained from different pharmaceutical factories located in different geographic regions were used to establish the electrophoretic fingerprint. MEEKC was performed using a Beckman PACE/MDQ system equipped with a diode-array detector and with monitoring at 280 nm. The fingerprint of resina draconis comprised 27 common peaks within 100 min. The relative standard deviations of the relative migration time of these common peaks were less than 2.1%. Through repetitive injection of the sample solution six times in 24 h, all relative standard deviations of the migration time and peak area of loureirin A and loureirin B were less than 2.5 and 3.8%, which demonstrated that the method had good stability and reproducibility. The relative peak areas of these common peaks in the electropherograms of four batches of resina draconis were processed with two mathematical methods, the correlation coefficient and the interangle cosine, to valuate the similarity. The values of the similarity degree of all samples were more than 0.91, which showed resina draconis samples from different origins were consistent. On the other hand, high-performance liquid chromatography (HPLC) coupled with photodiode-array detection was also applied to establish the fingerprint of resina draconis. The samples were separated with a LiChrospher C(18) column using acetonitrile (solvent A) and water containing 0.1% H(3)PO(4) (solvent B) as the mobile phase in linear gradient elution mode at a flow rate of 0.6 mL/min and detection was at 280 nm. There were only 20 common peaks in the HPLC fingerprint, and the values of the similarity degree of all samples were also more than 0.91. Though the similarity results of fingerprint analysis seemed to be the same, MEEKC resulted in more common peaks and higher separation efficiency for a variety of polarities of the components than HPLC. So, MEEKC was more suitable for development of the fingerprint of resina draconis.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía Capilar Electrocinética Micelar/métodos , Dracaena/química , Medicamentos Herbarios Chinos/química , Extractos Vegetales/análisis , Solventes/química , 1-Butanol/química , Acetonitrilos/química , Boratos/química , Tampones (Química) , Concentración de Iones de Hidrógeno , Octanos/química , Ácidos Fosfóricos/química , Extractos Vegetales/química , Dodecil Sulfato de Sodio/química , Factores de Tiempo
17.
Phytochem Anal ; 19(6): 499-505, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18546118

RESUMEN

INTRODUCTION: The quality evaluation of traditional Chinese medicine (TCM) represents a particular challenge owing to the complexity of the matrix, which renders separation and identification of the individual components extremely difficult. In recent years, fingerprinting of TCMs has played a dominant role in quality control. Resina Draconis was authorised as a new TCM in 1991, but a satisfactory HPLC fingerprint method for this preparation has not yet been published. OBJECTIVE: To develop a simple and reliable protocol for the quality control of Resina Draconis using an HPLC-PAD method. METHODOLOGY: The TCM was extracted with methanol at room temperature. Chromatography was carried out using a Lichrospher C(18) column eluted with a linear gradient of acetonitrile (A) and water containing 0.1% phosphoric acid (B), initially at 30:70 (A:B) and changing to 60:40 in 90 min. UV (PAD) spectra were acquired in the range 210-400 nm. RESULTS: Four chromatograms of samples of Resina Draconis obtained from different pharmaceutical factories showed 20 peaks in common. The average chromatogram was taken as a template from which the correlation coefficients and cosine ratios of the samples were determined. Whereas the contents of individual components in each sample were different, overall the samples were extremely similar one to another, and the products from different pharmaceutical factories were consistent. CONCLUSION: A reliable and validated HPLC method has been developed for the fingerprint analysis of Resina Draconis that can be applied for the quality control of this TCM.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Dracaena/química , Medicamentos Herbarios Chinos/análisis , Estándares de Referencia , Reproducibilidad de los Resultados
18.
J Chromatogr Sci ; 48(5): 399-405, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20515536

RESUMEN

Butyl-methacrylate-based porous monoliths were rapidly prepared in the fused-silica capillary with a 10-cm stripe of polyimide removed from its exterior. The photopolymerization could be carried out in 150 s using ethylene glycol dimethacrylate as a cross-linking agent; 1-propanol, 1,4-butanediol, and water as tri-porogenic solvents; and Irgacure 1800 as a photo-initiator. The effect of different morphologies on the efficiency and retention properties was investigated using pressure-assisted CEC (p-CEC), CEC, and low pressure-assisted liquid chromatography modes (LPLC). Baseline separation of the model analytes was respectively achieved including thiourea, toluene, naphthalene, and biphenyl with the lowest theoretical height up to 8.0 microm for thiourea in the mode of p-CEC. Furthermore, the influence of the tri-porogenic solvents on the morphology of methacrylate-based monoliths was systematically studied with mercury intrusion porosimetry and scanning electron microscopy.

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