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1.
J Cell Mol Med ; 27(10): 1362-1372, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37002788

RESUMEN

Renal transplantation is the only efficacious treatment for end-stage kidney disease. However, some people have developed renal insufficiency after transplantation, the mechanisms of which have not been well clarified. Previous studies have focused on patient factors, while the effect of gene expression in the donor kidney on post-transplant renal function has been less studied. Donor kidney clinical data and mRNA expression status were extracted from the GEO database (GSE147451). Weight gene co-expression network analysis (WGCNA) and differential gene enrichment analysis were performed. For external validation, we collected data from 122 patients who accepted renal transplantation at several hospitals and measured the level of target genes by qPCR. This study included 192 patients from the GEO data set, and 13 co-expressed genes were confirmed by WGCNA and differential gene enrichment analysis. Then, the PPI network contained 17 edges as well as 12 nodes, and four central genes (PRKDC, RFC5, RFC3 and RBM14) were identified. We found by collecting data from 122 patients who underwent renal transplantation in several hospitals and by multivariate logistic regression that acute graft-versus-host disease postoperative infection, PRKDC [Hazard Ratio (HR) = 4.44; 95% CI = [1.60, 13.68]; p = 0.006] mRNA level correlated with the renal function after transplantation. The prediction model constructed had good predictive accuracy (C-index = 0.886). Elevated levels of donor kidney PRKDC are associated with renal dysfunction after transplantation. The prediction model of renal function status for post-transplant recipients based on PRKDC has good predictive accuracy and clinical application.


Asunto(s)
Enfermedad Injerto contra Huésped , Fallo Renal Crónico , Trasplante de Riñón , Humanos , Trasplante de Riñón/efectos adversos , Regulación hacia Arriba , Supervivencia de Injerto , Fallo Renal Crónico/genética , Fallo Renal Crónico/cirugía , Proteína Quinasa Activada por ADN
2.
Ann Hematol ; 101(5): 953-961, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35149911

RESUMEN

Immune thrombocytopenia (ITP) is the most common clinical bleeding disorder with a high mortality rate and poor long-term survival quality in severe patients. There is controversy on how to choose the appropriate treatment. We systematically reviewed 19 randomized controlled trials (including 2615 participants) from January 1, 2015, to April 20, 2021. These investigations compared multiple drugs or their combinations in the therapeutic dose range for the treatment of ITP. The primary endpoint was based on the proportion of patients who responded to these therapies. The efficacy of eltrombopag plus rituximab, avatrombopag, dexamethasone plus anti-HP, and dexamethasone plus rhTPO was significantly higher than placebo (OR: 46.66, 29.44, 2.66, 1.86) or dexamethasone alone (OR: 46.22, 29.01, 2.22, 1.40). Placebo, oral immunosuppressants, and dexamethasone plus oseltamivir were less effective than the other ITP therapies tested. Eltrombopag plus rituximab may be the best choice when starting treatment for ITP.


Asunto(s)
Púrpura Trombocitopénica Idiopática , Benzoatos/uso terapéutico , Dexametasona/uso terapéutico , Humanos , Hidrazinas/uso terapéutico , Metaanálisis en Red , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Rituximab/uso terapéutico , Trombopoyetina/uso terapéutico
3.
Luminescence ; 33(7): 1164-1170, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30047614

RESUMEN

A sensitive resonance Rayleigh light scattering (RLS) assay for alpinetin was developed based on alpinetin-modified gold nanorods (AuNRs). Alpinetin could interact with AuNRs and formed a new assembly by electrostatic attraction. In pH 7.4 Tris-HCl buffer solution, the assembly of alpinetin-AuNRs showed a sensitive RLS signal. Under optimum conditions, the magnitude of enhanced RLS intensity (ΔIRLS ) was proportional to the concentration of alpinetin over the range 0.027-3.24 µg ml-1 , with a detection limit of 1.79 ng ml-1 (by 3σ). The developed RLS method was successfully applied to the detection of alpinetin in real or synthesized samples. Alpinetin recoveries were 90.4-108.7% with an RSD of 0.82-2.9% (n = 5) for Alpinia katsumadai samples, and 95.1-103.7% with an RSD of 0.28-3.9% (n = 5) for synthesized samples. The results showed that this new approach was convenient, reliable and sensitive.


Asunto(s)
Dispersión Dinámica de Luz/métodos , Flavanonas/análisis , Oro/química , Nanotubos/química , Dispersión Dinámica de Luz/instrumentación , Límite de Detección
4.
Tumour Biol ; 39(7): 1010428317716689, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28720068

RESUMEN

Wilms' tumor is associated with a high treatment success rate, but there is still a risk of recurrence. Cisplatin, which is one of the chemotherapeutic agents used for its treatment, is associated with a very high rate of resistance. Par-4 (prostate apoptosis response 4) is a tumor suppressor, which is capable of sensitizing tumor cells to chemotherapy. Therefore, the aim of this study was to determine whether combined treatment with Par-4 and cisplatin is effective for inhibiting growth of Wilms' tumor. Wilms' tumor and control cell samples were collected and analyzed by immunofluorescence assay and immunohistochemistry. Total proteins extracted from cultured cells were analyzed using western blotting and flow cytometry. In addition, a mouse xenograft model was established. We discovered significantly low expression of Par-4 in the tumor tissue, which was positively correlated with high expression of GRP78 (glucose-regulated protein 78). In addition, we found that ectopic Par-4 co-localized with cell surface GRP78 and induced high expression of the endoplasmic reticulum proteins ATF4 and BAX, which activated the endoplasmic reticulum apoptosis pathway. Moreover, treatment with ectopic Par-4 and cisplatin suppressed xenograft growth in nude mice. In conclusion, our results showed that Par-4 overexpression and cisplatin had a synergistic effect on SK-NEP-1 cells, as a result of which cell growth was inhibited and cellular apoptosis was induced. Thus, in vitro and in vivo upregulation of Par-4 expression is indispensable for the trafficking of GRP78 to the cell membrane and subsequent apoptosis of cancer cells.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/genética , Proteínas de Choque Térmico/genética , Tumor de Wilms/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisplatino/administración & dosificación , Resistencia a Antineoplásicos/genética , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/genética , Chaperón BiP del Retículo Endoplásmico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas de Choque Térmico/biosíntesis , Humanos , Ratones , Transducción de Señal/efectos de los fármacos , Transfección , Tumor de Wilms/genética , Tumor de Wilms/patología , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Luminescence ; 32(4): 502-508, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27594674

RESUMEN

A highly sensitive method for the detection of 6-mercaptopurine (MP) by resonance Rayleigh light scattering (RLS) method was developed. Gold nanoparticles (AuNPs) were synthesized by a modified seed method and characterized using transmission electron microscopy (TEM). AuNPs were bound to MP via covalent bonding to form the MP-AuNPs complex, which increased the RLS intensity of MP at 347 nm (increased by 65.7%). Under optimum conditions, the magnitude of the enhanced RLS intensity for MP-AuNPs was proportional to MP concentration in the range 0.0681-1.702 µg mL-1 . The linear regression equation was represented as follows: ΔIRLS = 9.31 + 82.42c (r = 0.9948). The limit of detection (LOD, 3σ) was 3.32 ng mL-1 . The system was applied successfully to detect MP in pharmaceuticals. MP recoveries were 99.9-101.7% with a relative standard deviation (RSD) (n = 5) of 0.59-0.77% for three synthetic samples, and 97.5-110.0% with an RSD of 0.98-2.10% (n = 5) for tablet samples.


Asunto(s)
Dispersión Dinámica de Luz/métodos , Mercaptopurina/análisis , Nanopartículas del Metal/química , Calibración , Dispersión Dinámica de Luz/normas , Oro/química , Concentración de Iones de Hidrógeno , Límite de Detección , Modelos Lineales , Mercaptopurina/química , Mercaptopurina/metabolismo , Microscopía Electrónica de Transmisión , Concentración Osmolar , Sensibilidad y Especificidad , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Comprimidos/análisis
6.
Biol Blood Marrow Transplant ; 22(2): 220-225, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26476204

RESUMEN

Outcomes for hematopoietic stem cell transplantation (HSCT) in various donor and recipient killer immunoglobulin-like receptor (KIR) genotypes have been studied extensively. The associations between KIR2DS4 and its variant KIR1D with outcomes of HSCT from a sibling-related HLA-matched donor with KIR haplotype A have not been explored, however. To study this, we genotyped donor-recipient pairs and divided 165 recipients of HSCT from a KIR gene haplotype A donor into 3 groups: 2DS4+/2DS4+ (2 intact KIR2DS4 alleles), 2DS4+/1D+ (heterozygous), and 1D+/1D+ (homozygous for the deletion variant KIR1D). No difference in the recovery of neutrophils and platelets among the 3 groups was observed. The cumulative incidence of grade III-IV acute graft-versus-host disease (aGVHD) within day +100 was 28.94% in the 2DS4+/2DS4+ group, 14.11% in the 2DS4+/1D+ group, and 44.44% in the 1D+/1D+ group (P = .0159). Multivariate analysis identified 1D+/1D+ as an independent risk factor for aGVHD (hazard ratio [HR], 4.221; 95% confidence interval [CI], 1.470 to 12.124; P = .007). In contrast, the cumulative incidences of chronic GVHD, 3-year cumulative relapse, and treatment-related mortality did not differ significantly among the 3 groups. The rate of cytomegalovirus (CMV) reactivation was 46.96% in the 2DS4+/2DS4+ group, 20.16% in the 2DS4+/1D+ group, and 53.25% in the 1D+/1D+ group (P = .0017). Multivariate analysis identified 2DS4+/1D+ as an independent protective factor for CMV reactivation (HR, 0.268; 95% CI, 0.125 to 0.574; P = .001). Although overall survival (OS) did not differ among the groups in the first year, the 2DS4(+)/2DS4(+) group had significantly better OS than the other groups after 1 year (P = .0361). In patients with advanced-stage disease, the 3-year probability of disease-free survival was 51.06% in the 2DS4+/2DS4+ group, 34.01% in the 2DS4+/1D+ group, and 0% in the 1D+/1D+ group (P = .0314). Collectively, our data suggest that the KIR 2DS4/1D allelic variance is associated with the outcome of sibling-related HLA-matched HSCT, and that donor subclassification of KIR 2DS4/1D alleles should be considered in this setting.


Asunto(s)
Citomegalovirus/genética , Enfermedad Injerto contra Huésped/genética , Trasplante de Células Madre Hematopoyéticas/métodos , Receptores KIR/genética , Receptores KIR/metabolismo , Acondicionamiento Pretrasplante/métodos , Adolescente , Adulto , Niño , Femenino , Genotipo , Haplotipos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Hermanos , Análisis de Supervivencia , Donantes de Tejidos , Resultado del Tratamiento , Adulto Joven
7.
Luminescence ; 31(4): 1013-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26597997

RESUMEN

The interaction of paylean (PL) with calf thymus DNA (ctDNA) was investigated using fluorescence spectroscopy, UV absorption, melting studies, ionic strength, viscosity experiments and molecular docking under simulated physiological conditions. Values for the binding constant Ka between PL and DNA were 5.11 × 10(3) , 2.74 × 10(3) and 1.74 × 10(3) L mol(-1) at 19, 29 and 39°C respectively. DNA quenched the intrinsic fluorescence of PL via a static quenching procedure as shown from Stern-Volmer plots. The relative viscosity and the melting temperature of DNA were basically unchanged in the presence of PL. The fluorescence intensity of PL-DNA decreased with increasing ionic strength. The value of Ka for PL with double-stranded DNA (dsDNA) was larger than that for PL with single-stranded DNA (ssDNA). All the results revealed that the binding mode was groove binding, and molecular docking further indicated that PL was preferentially bonded to A-T-rich regions of DNA. The values for ΔH, ΔS and ΔG suggested that van der Waals forces or hydrogen bonding might be the main acting forces between PL and DNA. The binding distance was determined to be 3.37 nm based on the theory of Förster energy transference, which indicated that a non-radiation energy transfer process occurred. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Butilaminas/química , ADN/química , Fluorescencia , Simulación del Acoplamiento Molecular , Fenoles/química , Animales , Sitios de Unión , Bovinos , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
8.
Luminescence ; 31(2): 372-379, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26179292

RESUMEN

The interactions of mapenterol with bovine serum albumin (BSA) and human serum albumin (HSA) have been investigated systematically using fluorescence spectroscopy, absorption spectroscopy, circular dichroism (CD) and molecular docking techniques. Mapenterol has a strong ability to quench the intrinsic fluorescence of BSA and HSA through static quenching procedures. At 291 K, the binding constants, Ka, were 1.93 × 10(3) and 2.73 × 10(3) L/mol for mapenterol-BSA and mapenterol-HAS, respectively. Electrostatic forces and hydrophobic interactions played important roles in stabilizing the mapenterol-BSA/has complex. Using site marker competitive studies, mapenterol was found to bind at Sudlow site I on BSA/HSA. There was little effect of K(+), Ca(2+), Cu(2+), Zn(2+) and Fe(3+) on the binding. The conformation of BSA/HSA was changed by mapenterol, as seen from the synchronous fluorescence spectra. The CD spectra showed that the binding of mapenterol to BSA/HSA changed the secondary structure of BSA/HSA. Molecular docking further confirmed that mapenterol could bind to Sudlow site I of BSA/HSA. According to Förster non-radiative energy transfer theory (FRET), the distances r0 between the donor and acceptor were calculated as 3.18 and 2.75 nm for mapenterol-BSA and mapenterol-HAS, respectively.


Asunto(s)
2-Hidroxifenetilamina/análogos & derivados , Compuestos de Anilina/química , Simulación del Acoplamiento Molecular , Albúmina Sérica/química , 2-Hidroxifenetilamina/química , Animales , Bovinos , Dicroismo Circular , Humanos , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
10.
Clin Rheumatol ; 42(5): 1423-1433, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36595110

RESUMEN

INTRODUCTION: Systemic lupus erythematosus (SLE) is a heterogeneous and chronic autoimmune disease. Aberrant DNA methylation occurs during various processes of SLE development regulating the mRNA expression of interrelated genes. This study aims to screen potential DNA methylation markers for SLE. METHODS: Gene expression and methylation datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between SLE patients and healthy controls were screened using the limma R package, and differentially methylated positions (DMPs) and regions (DMRs) were identified using dmpfinder and bumphunter (minfi). Additionally, the DNA methylation markers to distinguish SLE patients from healthy controls were explored through receiver operating characteristic (ROC) curves and logistic regression analyses. Finally, we validated the results of the bioinformatic analysis by pyrosequencing. RESULTS: In total, 91 DEGs, 90,092 DMPs, 15 DMRs, and 13 DMR-associated genes were identified. Through the integrative analysis of DEG- and DMR-associated genes, we identified five type I interferon (IFN)-related genes as key epigenetic-driven genes in SLE. GO enrichment analysis showed that the five SLE-associated epigenetic-driven genes were mainly enriched in the type I IFN signaling pathway involved in immune response and defense response to virus. Moreover, we identified two SLE-specific DNA methylation markers, three SLE without lupus nephritis (SLE-LN-)-specific DNA methylation markers, and two SLE with lupus nephritis (SLE-LN+)-specific DNA methylation markers by stepwise logistic regression. CONCLUSIONS: Overall, our study demonstrates potential DNA methylation markers of SLE, SLE-LN-, and SLE-LN+, which may help the diagnosis, boost the development of new epigenetic therapy, and contribute to individualized treatment. Key Points • This study identified five type I IFN-related genes as key epigenetic-driven genes in SLE, which support the importance of the type I IFN pathway in the pathogenesis of SLE • We identified novel DNA methylation biomarkers in SLE, SLE-LN-, and SLE-LN+ by a comprehensive analysis of bioinformatics methods and executed experimental validation, and binary logistic regression analysis showed that they have excellent potential • These results may provide new insights into the biological mechanisms of SLE, and identify reliable biomarkers for SLE, SLE-LN-, and SLE-LN+, which may contribute to diagnosis and individualized treatment.


Asunto(s)
Interferón Tipo I , Lupus Eritematoso Sistémico , Nefritis Lúpica , Humanos , Nefritis Lúpica/genética , Metilación de ADN , Biomarcadores/metabolismo , Interferón Tipo I/genética , Expresión Génica
11.
Clin Cosmet Investig Dermatol ; 15: 1809-1813, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105748

RESUMEN

Introduction: Riehl's melanosis (RM) is an acquired hyperpigmentation disorder, presenting diffused and reticulate brownish-gray pigmentation, preferentially on the face and neck. RM overlaps with systemic lupus erythematosus (SLE) and Hashimoto's thyroiditis has never been reported. Case: We report a case of RM patient accompanied with SLE and Hashimoto's thyroiditis of primary hypothyroidism. Progressing, diffuse, symmetric, and reticular hyperpigmentation was seen on the face, neck, and upper limbs, manifesting as typical melanosis. Skin microscopy showed diffuse black-pepper-like changes and telangiectasias. The diagnosis of SLE and primary hypothyroidism were confirmed by follow-up investigations. The hyperpigmentation turned notably lighter after 14 months of treatment with prednisone, hydroxychloroquine, and L-thyroxine. Discussion: The exact pathogenesis of RM is unclear and exposure to coal tar dyes, ultraviolet, and fragrance fixatives in cosmetics are believed to be contributing factors, while some cases involve no triggers. It is not impossible that RM is a rare skin manifestation of SLE that has never been reported. The skin hyperpigmentation in this patient was not triggered by thyroid disease. Conclusion: RM could be a skin manifestation of autoimmunity. Coexistence of RM, lupus erythematosus and thyroiditis in the same patient is rare and has never been reported.

12.
J Biomol Struct Dyn ; 37(6): 1464-1476, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29685085

RESUMEN

Two aminoglycosides, micronomicin (MN), and tobramycin (TB), binding with DNA were studied using various spectroscopic techniques including fluorescence, UV-Vis, FT-IR, and CD spectroscopy coupled with relative viscosity and molecular docking. Studies of fluorescence quenching and time-resolved fluorescence spectroscopy all revealed that MN/TB quenching the fluorescence of DNA-EB belonged to static quenching. The binding constants and binding sites were obtained. The values of ΔH, ΔS, and ΔG suggested that van der Waals force or hydrogen bond might be the main binding force. FT-IR and CD spectroscopy revealed that the binding of MN/TB with DNA had an effect on the secondary structure of DNA. Binding mode of MN/TB with DNA was groove binding which was ascertained by viscosity measurements, CD spectroscopy, ionic strength, melting temperature (Tm), contrast experiments with single stranded (ssDNA), and double stranded DNA (dsDNA). Molecular docking analysis further confirmed that the groove binding was more acceptable result.


Asunto(s)
ADN/química , Gentamicinas/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Tobramicina/química , Sitios de Unión , Etidio/química , Estructura Molecular , Reología , Análisis Espectral , Termodinámica
13.
J Biomol Struct Dyn ; 37(13): 3496-3505, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30176766

RESUMEN

The interaction of fisetholz with bovine serum albumin (BSA) and human serum albumin (HSA) was investigated by multi-spectroscopic, cyclic voltammetric, and molecular docking technique. The results revealed that there was a static quenching of BSA/HSA induced by fisetholz. The binding constants (Ka) and binding sites (n) were calculated at different temperatures (293, 303, and 311 K). The enthalpy change (ΔH) were calculated to be -17.20 kJ mol-1 (BSA) and -18.28 kJ mol-1 (HSA) and the entropy change (ΔS) were calculated to be 35.41 J mol-1 (BSA) and 24.02 J mol-1 (HSA), respectively, which indicated that the interaction between fisetholz and BSA/HSA was mainly by electrostatic attraction. Based on displacement experiments using site probes, indomethacin and ibuprofen, the binding site of fisetholz to BSA/HSA was identified as sub-domain IIIA, which was further confirmed by molecular docking method. There was little effect of K+, Ca2+, Cu2+, Zn2+, and Fe3+ on fisetholz-BSA or fisetholz-HSA complex. The spectra of synchronous fluorescence, circular dichroism (CD) and Fourier transform infrared (FT-IR) all showed that fisetholz binding to BSA/HSA leads to secondary structures change of the two serum albumins. According to the Förster non-radiation energy transfer theory, the binding distance between fisetholz and BSA/HSA was 2.94/4.68 nm. The cyclic voltammetry as a supporting tool also indicated that fisetholz interacted with protein. Communicated by Ramaswamy H. Sarma.


Asunto(s)
Flavonoides/metabolismo , Simulación del Acoplamiento Molecular , Albúmina Sérica Bovina/metabolismo , Albúmina Sérica Humana/metabolismo , Animales , Sitios de Unión , Bovinos , Flavonoides/química , Humanos , Ligandos , Modelos Moleculares , Estructura Molecular , Unión Proteica , Conformación Proteica , Albúmina Sérica Bovina/química , Albúmina Sérica Humana/química , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
14.
J Biomol Struct Dyn ; 35(10): 2077-2089, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27392082

RESUMEN

The binding of neomycin sulfate (NS)/paromomycin sulfate (PS) with DNA was investigated by fluorescence quenching using acridine orange (AO) as a fluorescence probe. Fluorescence lifetime, FT-IR, circular dichroism (CD), relative viscosity, ionic strength, DNA melting temperature, and molecular docking were performed to explore the binding mechanism. The binding constant of NS/PS and DNA was 6.70 × 103/1.44 × 103 L mol-1 at 291 K. The values of ΔHθ, ΔSθ, and ΔGθ suggested that van der Waals force or hydrogen bond might be the main binding force between NS/PS and DNA. The results of Stern-Volmer plots and fluorescence lifetime measurements all revealed that NS/PS quenching the fluorescence of DNA-AO was static in nature. FT-IR indicated that the interaction between DNA and NS/PS did occur. The relative viscosity and melting temperature of DNA were almost unchanged when NS/PS was introduced to the solution. The fluorescence intensity of NS/PS-DNA-AO was decreased with the increase in the ionic strength. For CD spectra of DNA, the intensity of positive band at nearly 275 nm was decreased and that of negative band at nearly 245 nm was increased with the increase in the concentration of NS/PS. The binding constant of NS/PS with double-stranded DNA (dsDNA) was larger than that of NS/PS with single-stranded DNA (ssDNA). From these studies, the binding mode of NS/PS with DNA was evaluated to be groove binding. The results of molecular docking further indicated that NS/PS could enter into the minor groove in the A-T rich region of DNA.


Asunto(s)
Naranja de Acridina/química , ADN de Cadena Simple/química , ADN/química , Colorantes Fluorescentes/química , Neomicina/química , Paromomicina/química , Animales , Sitios de Unión , Bovinos , Enlace de Hidrógeno , Cinética , Simulación del Acoplamiento Molecular , Conformación de Ácido Nucleico , Desnaturalización de Ácido Nucleico , Concentración Osmolar , Soluciones , Temperatura , Termodinámica , Viscosidad
15.
Mater Sci Eng C Mater Biol Appl ; 58: 1001-7, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26478397

RESUMEN

A new resonance light scattering (RLS) method for determining eugenol was developed using gold nanorods (AuNRs) as probes which were synthesized in our lab. The weak RLS intensity of eugenol was obviously enhanced by the use of AuNRs. All of the results from the SEM, RLS and UV spectra indicated that eugenol induced the assembly of AuNRs; thus, a new complex of AuNRs-eugenol was formed. The assembly of this new complex was achieved through a coordination bond between eugenol and AuNRs. Under optimum experimental conditions, a direct linear relationship was established between the enhancement of RLS intensity and the concentration of eugenol in the range of 0.043-10.60 µg ml(-1) (r=0.9927). Moreover, the limit of detection (LOD) was found at a nanogram level (7.28 ng ml(-1) by 3S0/S). The recovery and RSD (n=5) of three synthetic samples were 99.7-104.2% and 0.81-1.19%, respectively. The method was successfully employed for the analysis of eugenol in curry powder samples.


Asunto(s)
Eugenol/análisis , Oro/química , Nanotubos/química , Dispersión de Radiación , Concentración de Iones de Hidrógeno , Luz , Límite de Detección , Nanotubos/ultraestructura , Concentración Osmolar , Espectrofotometría Ultravioleta
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 146: 255-60, 2015 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-25819313

RESUMEN

A new method for the determination of calf thymus DNA at nanogram level was proposed based on the enhanced resonance light scattering (RLS) signals of DNA in the presence of procyanidin and cetylpyridinium bromide dihydrate (CPB). Under the experimental conditions, the RLS intensity of DNA at 291.0 nm was greatly enhanced by procyanidin-CPB at pH 7.0. There was a good linear relationship (r=0.9993) between the enhanced RLS intensity (ΔI(RLS)) and DNA concentration of 0.0084-3.36 µg mL(-1). The limit of detection (LOD) was 2.27 ng mL(-1) (3S0/S). Three synthetic DNA samples were measured with satisfactory, and the recovery was 102.3-107.2%.


Asunto(s)
Biflavonoides/química , Catequina/química , Cetilpiridinio/química , ADN/química , Luz , Proantocianidinas/química , Dispersión de Radiación , Animales , Bovinos
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 1074-9, 2015 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-25173524

RESUMEN

The paper explores the method of determination of salmeterol xinafoate at nanogram level with gold nanoparticles (AuNPs) probe, to measure the intensity of resonance Rayleigh light scattering (RLS) by a common spectrofluorometer. The RLS intensity of salmeterol xinafoate was greatly enhanced by AuNPs, with the maximum scattering peak at 357 nm. The salmeterol xinafoate was determined basing on the binding of salmeterol xinafoate to AuNPs by electrostatic adsorption. Under the optimum conditions, the enhanced RLS intensity was directly proportional to the concentration of salmeterol xinafoate in the range of 0.054-6.038 µg mL(-1) with a good linear relationship (r=0.9928). The limit of detection (LOD) was 9.48 ng mL(-1). The interference tests were performed carefully. With the proposed method, the synthetic samples were analyzed satisfactorily, the recovery and RSD were 102.5-103.0% and 0.67-1.0% respectively.


Asunto(s)
Albuterol/análogos & derivados , Oro/química , Nanopartículas del Metal/química , Dispersión de Radiación , Albuterol/análisis , Albuterol/química , Calibración , Concentración de Iones de Hidrógeno , Límite de Detección , Nanopartículas del Metal/ultraestructura , Concentración Osmolar , Xinafoato de Salmeterol , Cloruro de Sodio/química , Espectrofotometría Ultravioleta , Factores de Tiempo
19.
Artículo en Inglés | MEDLINE | ID: mdl-26123508

RESUMEN

The interaction of terbutaline sulfate (TS) with calf thymus DNA (ctDNA) were investigated by fluorescence quenching, UV-vis absorption, viscosity measurements, ionic strength effect, DNA melting experiments and molecular docking. The binding constants (Ka) of TS to ctDNA were determined as 4.92×10(4), 1.26×10(4) and 1.16×10(4) L mol(-1) at 17, 27 and 37 °C, respectively. Stern-Volmer plots suggested that the quenching of fluorescence of TS by ctDNA was a static quenching. The absorption spectra of TS with ctDNA revealed a slight blue shift and hyperchromic effect. The relative viscosity ctDNA was hardly changed by TS, and melting temperature varied slightly. For the system of TS-ctDNA, the intensity of fluorescence decreased with the increase of ionic strength. Also, the Ka for TS-double stranded DNA (dsDNA) was clearly weaker than that for TS-single stranded DNA (ssDNA). All these results revealed that the binding mode of TS with ctDNA should be groove binding. The enthalpy change and entropy change suggested that van der Waals force or hydrogen bonds was a main binding force between TS and ctDNA. Furthermore, the quantum yield of TS was measured by comparing with the standard solution. Based on the Förster energy transference theory (FRET), the binding distance between the acceptor and donor was calculated. Molecular docking showed that TS was a minor groove binder of ctDNA and preferentially bound to A-T rich regions.


Asunto(s)
Broncodilatadores/metabolismo , ADN/metabolismo , Terbutalina/metabolismo , Animales , Bovinos , Simulación del Acoplamiento Molecular , Concentración Osmolar , Unión Proteica , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Termodinámica , Viscosidad
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