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1.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-967907

RESUMO

Background@#Highly pathogenic avian influenza viruses (HPAIVs) is an extremely contagious and high mortality rates in chickens resulting in substantial economic impact on the poultry sector. Therefore, it is necessary to elucidate the pathogenic mechanism of HPAIV for infection control. @*Objective@#Gene set enrichment analysis (GSEA) can effectively avoid the limitations of subjective screening for differential gene expression. Therefore, we performed GSEA to compare HPAI-infected resistant and susceptible Ri chicken lines. @*Methods@#The Ri chickens Mx(A)/BF2(B21) were chosen as resistant, and the chickens Mx(G)/ BF2(B13) were selected as susceptible by genotyping the Mx and BF2 genes. The tracheal tissues of HPAIV H5N1 infected chickens were collected for RNA sequencing followed by GSEA analysis to define gene subsets to elucidate the sequencing results. @*Results@#We identified four differentially expressed pathways, which were immune-related pathways with a total of 78 genes. The expression levels of cytokines (IL-1β, IL-6, IL-12), chemokines (CCL4 and CCL5), type interferons and their receptors (IFN-β, IFNAR1, IFNAR2, and IFNGR1), Jak-STAT signaling pathway genes (STAT1, STAT2, and JAK1), MHC class I and II and their co-stimulatory molecules (CD80, CD86, CD40, DMB2, BLB2, and B2M), and interferon stimulated genes (EIF2AK2 and EIF2AK1) in resistant chickens were higher than those in susceptible chickens. @*Conclusions@#Resistant Ri chickens exhibit a stronger antiviral response to HPAIV H5N1 compared with susceptible chickens. Our findings provide insights into the immune responses of genetically disparate chickens against HPAIV.

3.
Crit Rev Anal Chem ; 47(1): 67-75, 2017 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-27404559

RESUMO

Vibrational spectroscopy offers a unique opportunity to investigate the composition of unknown substances on a molecular basis. The spectroscopy of molecular vibrations using mid-infrared or Raman techniques has been applied to samples of body fluids. This review presents some applications related to body fluids published in the period 2005-2015.


Assuntos
Líquidos Corporais/química , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos , Carboidratos/análise , Humanos , Lipídeos/análise , Ácidos Nucleicos/análise , Proteínas/análise , Vibração
4.
Crit Rev Anal Chem ; 47(3): 194-203, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27786540

RESUMO

Vibrational spectroscopy (Infrared (IR) and Raman) and, in particular, micro-spectroscopy and micro-spectroscopic imaging have been used to characterize developmental changes in tissues, to monitor these changes in cell cultures and to detect disease and drug-induced modifications. The conventional methods for biochemical and histophatological tissue characterization necessitate complex and "time-consuming" sample manipulations and the results are rarely quantifiable. The spectroscopy of molecular vibrations using mid-IR or Raman techniques has been applied to samples of human tissue. This article reviews the application of these vibrational spectroscopic techniques for analysis of biological tissue published between 2005 and 2015.


Assuntos
Neoplasias/patologia , Análise Espectral/métodos , Vibração , Humanos , Espectrofotometria Infravermelho/instrumentação , Análise Espectral Raman/instrumentação
5.
Food Chem ; 196: 877-84, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26593568

RESUMO

Milk is a fluid containing several substances, and its composition depends on several factors. Vibrational spectroscopy is a powerful tool to determine the constituent concentrations and qualitative characteristics of dairy products. Vibrational spectrometry covers a series of well-established analytical methodologies suitable to be employed for both qualitative and quantitative purposes. In the first part of this review, theoretical aspects on vibrational techniques are presented; in the second part, the most important papers, published during the period 2009-2015, related to milk analysis are discussed.

6.
Crit Rev Anal Chem ; 45(2): 156-65, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25558776

RESUMO

This review provides a brief background to the application of infrared spectroscopy, including Fourier transform-infrared spectroscopy, in biological fluids. It is not meant to be complete or exhaustive but to provide the reader with sufficient background for selected applications in cancer diagnostics. Fourier transform-infrared spectroscopy (FT-IR) is a fast and nondestructive analytical method. The infrared spectrum of a mixture serves as the basis to quantitate its constituents, and a number of common clinical chemistry tests have proven to be feasible using this approach. This review focuses on biomedical FT-IR applications, published in the period 2009-2013, used for early detection of cancer through qualitative and quantitative analysis.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias/diagnóstico , Espectrofotometria/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Humanos
7.
Artigo em Inglês | MEDLINE | ID: mdl-25546493

RESUMO

The application of chemometrics-assisted UV spectrophotometry and RP-HPLC to the simultaneous determination of chloramphenicol, dexamethasone and naphazoline in ternary and quaternary mixtures is presented. The spectrophotometric procedure is based on the first-order derivative and wavelet transforms of ratio spectra using single, double and successive divisors. The ratio spectra were differentiated and smoothed using Savitzky-Golay filter; whereas wavelet transform realized with wavelet functions (i.e. db6, gaus5 and coif3) to obtain highest spectral recoveries. For the RP-HPLC procedure, the separation was achieved on a ZORBAX SB-C18 (150×4.6 mm; 5 µm) column at ambient temperature and the total run time was less than 7 min. A mixture of acetonitrile - 25 mM phosphate buffer pH 3 (27:73, v/v) was used as the mobile phase at a flow rate of 1.0 mL/min and the effluent monitored by measuring absorbance at 220 nm. Calibration graphs were established in the range 20-70 mg/L for chloramphenicol, 6-14 mg/L for dexamethasone and 3-8 mg/L for naphazoline (R(2)>0.990). The RP-HPLC and ratio spectra transformed by a combination of derivative-wavelet algorithms proved to be able to successfully determine all analytes in commercial eye drop formulations without sample matrix interference (mean percent recoveries, 97.4-104.3%).


Assuntos
Cloranfenicol/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Dexametasona/análise , Nafazolina/análise , Raios Ultravioleta , Análise de Ondaletas , Calibragem , Cloranfenicol/química , Dexametasona/química , Nafazolina/química , Soluções Oftálmicas , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
8.
ScientificWorldJournal ; 2014: 313609, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24949492

RESUMO

The application of first-order derivative and wavelet transforms to UV spectra and ratio spectra was proposed for the simultaneous determination of ibuprofen and paracetamol in their combined tablets. A new hybrid approach on the combined use of first-order derivative and wavelet transforms to spectra was also discussed. In this application, DWT (sym6 and haar), CWT (mexh), and FWT were optimized to give the highest spectral recoveries. Calibration graphs in the linear concentration ranges of ibuprofen (12-32 mg/L) and paracetamol (20-40 mg/L) were obtained by measuring the amplitudes of the transformed signals. Our proposed spectrophotometric methods were statistically compared to HPLC in terms of precision and accuracy.


Assuntos
Acetaminofen/análise , Ibuprofeno/análise , Espectrofotometria Ultravioleta/métodos , Comprimidos/química , Análise de Ondaletas
9.
Artigo em Inglês | MEDLINE | ID: mdl-24374557

RESUMO

Signal processing methods based on the use of derivative, Fourier and wavelet transforms were proposed for the spectrophotometric simultaneous determination of cefoperazone and sulbactam in powders for injection. These transforms were successfully applied to UV spectra and ratio spectra to find suitable working wavelengths. Wavelet signal processing was proved to have distinct advantages (i.e. higher peak intensity obtained, additional smooth function and scaling factor process eliminated) over derivative and Fourier transforms. Especially, a better resolution of spectral overlapping bands was obtained by the use of double signal transform in the sequences such as (i) spectra pre-processed by Fractional Wavelet Transform and subsequently subjected to Continuous Wavelet Transform or Discrete Wavelet Transform, and (ii) derivative - wavelet transforms combined. Calibration graphs for cefoperazone and sulbactam were recorded for the range 10-35 mg/L. Good accuracy and precision were reported for all proposed methods by analyzing synthetic mixtures of cefoperazone and sulbactam. Furthermore, these methods were statistically comparable to RP-HPLC.


Assuntos
Cefoperazona/análise , Análise de Fourier , Espectrofotometria Ultravioleta/métodos , Sulbactam/análise , Análise de Ondaletas , Análise de Variância , Calibragem , Cefoperazona/química , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Reprodutibilidade dos Testes , Sulbactam/química
10.
J Anal Methods Chem ; 2013: 367914, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24109542

RESUMO

The electroreduction behaviour and determination of cefoperazone using a hanging mercury drop electrode were investigated. Cyclic voltammograms of cefoperazone recorded in universal Britton-Robinson buffers pH 3-6 exhibited a single irreversible cathodic peak. The process was adsorption-controlled. Britton-Robinson buffer 0.04 M pH 4.0 was selected as a supporting electrolyte for quantitative purposes by differential pulse and square wave adsorptive cathodic stripping voltammetry. The experimental voltammetric conditions were optimized using Central Composite Face design. A reduction wave was seen in the range from -0.7 to -0.8 V. These voltammetric techniques were successfully validated as per ICH guidelines and applied for the determination of cefoperazone in its single and sulbactam containing powders for injection and statistically comparable to USP-HPLC. They were further extended to determine cefoperazone in spiked human urine with no matrix effect.

11.
Int J Pharm ; 238(1-2): 247-56, 2002 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11996828

RESUMO

The objectives of this study were to validate and compare the suitability of different primary cell culture systems as models to investigate peptide enzymatic stability following nasal administration. The degradation kinetics of a model peptide, leucine enkephalin (Tyr-Gly-Gly-Phe-Leu, Leu-Enk), was determined in four nasal cell culture systems: immersion, air-liquid interface, sequential monolayer-suspension, floating collagen. The influence of enzyme inhibitors (bestatin, puromycin) and Leu-Enk metabolite analogs (Tyr-Gly, Phe-Leu, Tyr-Gly-Gly, Gly-Phe-Leu) on the Leu-Enk degradation profile was also investigated. The disappearance of Leu-Enk in all the cell culture systems followed first order kinetics. The specific activity in the cell culture systems followed the rank: sequential monolayer-suspension (32.60 microM min(-1) mg(-1)) >air-liquid interface (15.19 microM min(-1) mg(-1)) >immersion (11.49 microM min(-1) mg(-1)) >floating collagen (4.57 microM min(-1) mg(-1)). At equimolar concentration, bestatin had a higher inhibitory effect than puromycin. The rate of hydrolysis of Leu-Enk was reduced significantly by co-incubation with Leu-Enk metabolite analogs. This study showed that immersion, sequential monolayer-suspension and air-liquid interface culture systems may be potentially suitable for further studies on peptide enzymatic stability following nasal administration.


Assuntos
Células Epiteliais/metabolismo , Mucosa Nasal/metabolismo , Peptídeos/metabolismo , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Colágeno/metabolismo , Meios de Cultura , Técnicas Citológicas , Encefalina Leucina/análogos & derivados , Encefalina Leucina/metabolismo , Células Epiteliais/efeitos dos fármacos , Humanos , Cinética , Mucosa Nasal/efeitos dos fármacos , Preparações Farmacêuticas/metabolismo , Inibidores de Proteases/farmacologia , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
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