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1.
Food Chem ; 458: 140266, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38964095

RESUMEN

The interaction between proteins and soluble dietary fibers plays a vital role in the development of animal-derived foods. Herein, the effects of different contents (0-3.0%) of round-bracted psyllium husk powder (PHP) on the gelation behavior, microstructure, and intermolecular interactions of Andrias davidianus myofibrillar protein (MP) were investigated. Rheological and chemical forces suggested that PHP (1.5%-2.0%) enhanced the functional properties of MP at low ionic strength, thereby increasing the viscoelasticity of mixed gels. SDS-PAGE revealed that PHP reinforced the cross-linking and aggregation of protein molecules. Circular dichroism spectroscopy, low-field nuclear magnetic resonance, and scanning electron microscopy demonstrated that PHP induced the transformation of α-helix (decreased by 14.85%) to an ordered ß-sheet structure (increased by 81.58%), which was more favorable for the formation of dense network structure and improved (10.53%) the water retention of MP gels. This study provided new insights for PHP to effectively meliorate the heat-induced gelling properties of MP.

2.
Apoptosis ; 26(11-12): 628-638, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34748127

RESUMEN

ANNEXIN V belongs to a family of phospholipid binding proteins which is able to bind to negatively charged phospholipids such as phosphatidylserine (PS) in the presence of a high affinity Ca2+ ion. When apoptosis occurs, even at early stage, PS will be exposed to the outside of the cell surface from the cytoplasm side of membrane leaflets., Therefore ANNEXIN V has been suggested as a bio-marker for imaging early apoptotic events of various cell death including those in disease conditions. However, most ANNEXIN V-based apoptotic detecting techniques were in vitro approaches. Here, we presented a new BRET (Bioluminescence Resonance Energy Transfer) based genetic coded biosensor by fusing ANNEXIN V and a BRET version of NanoLuc (teLuc) for both in vitro and in vivo apoptosis detection. The BRET feature of this new sensor makes it convenient to be applied to both conventional fluorescent-based in vitro apoptosis detection and bioluminescence-based animal live imaging for in vivo study. Because of its robust bioluminescence signal, it is possible to perform the evaluation of the disease-induced apoptotic damage and recovery process directly at deep tissue level in live animal.


Asunto(s)
Apoptosis , Técnicas Biosensibles , Animales , Anexina A5/genética , Luciferasas
3.
Food Res Int ; 139: 109943, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33509496

RESUMEN

Volatiles and microbiome from different Xiang xi sausages (HBD, HBN, HHY and HDK) were performed by Chromatography-Ion Mobility Spectrometry and Illumina MiSeq platform (16 S rRNA and ITS sequencing). Results indicated that ethanol, ethyl acetate, ethyl-propanoate, pinene, limonene, cineole, etc. were the key (main) volatiles; whereas staphylococcus, lactobacillus, solanum-torvum, brochothrix and debaryomyces, candida were the dominant bacteria and fungi, respectively. The variation and relationship between microbiome and volatiles were disclosed by multivariate and spearman's correlation analysis. Volatiles of HDK is similar to HBN and HBD compared to HHY, while microbiome community of HHY is similar to HBN and HDK compared to HBD. Solanum-torvum, pseudomonas (bacteria) and debaryomyces (fungi) contributed positively to the development of major volatiles in Xiangxi sausages. Meanwhile, 'carbohydrate metabolism', 'amino acid metabolism' (microbia) and glycolysis/gluconeogenesis (volatiles) were commented in KEGG database. This study provides a deep insight into the relation between volatiles and microbiome (bacteria and fungi) of Xiangxi sausages.


Asunto(s)
Productos de la Carne , Microbiota , Bacterias , Hongos , Lactobacillus , Productos de la Carne/análisis
4.
J Adv Res ; 25: 49-56, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32922973

RESUMEN

In this paper, the fractional-order modeling of multiple groups of lithium-ion batteries with different states is discussed referring to electrochemical impedance spectroscopy (EIS) analysis and iterative learning identification method. The structure and parameters of the presented fractional-order equivalent circuit model (FO-ECM) are determined by EIS from electrochemical test. Based on the working condition test, a P-type iterative learning algorithm is applied to optimize certain selected model parameters in FO-ECM affected by polarization effect. What's more, considering the reliability of structure and adaptiveness of parameters in FO-ECM, a pre-tested nondestructive 1 / f noise is superimposed to the input current, and the correlative information criterion (CIC) is proposed by means of multiple correlations of each parameter and confidence eigen-voltages from weighted co-expression network analysis method. The tested batteries with different state of health (SOH) can be successfully simulated by FO-ECM with rarely need of calibration when excluding polarization effect. Particularly, the small value of CIC α indicates that the fractional-order α is constant over time for the purpose of SOH estimation. Meanwhile, the time-varying ohmic resistance R 0 in FO-ECM can be regarded as a wind vane of SOH due to the large value of CIC R 0 . The above analytically found parameter-state relations are highly consistent with the existing literature and empirical conclusions, which indicates the broad application prospects of this paper.

5.
Inorg Chem ; 57(10): 6051-6056, 2018 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-29722989

RESUMEN

The quaternary compound Cu2ZnSnSe4 (CZTSe), as a typical candidate for both solar cells and thermoelectrics, is of great interest for energy harvesting applications. Materials with a high thermoelectric efficiency have a relatively low thermal conductivity, which is closely related to their chemical bonding and lattice dynamics. Therefore, it is essential to investigate the lattice dynamics of materials to further improve their thermoelectric efficiency. Here we report a lattice dynamic study in a cobalt-substituted CZTSe system using temperature-dependent X-ray absorption fine structure spectroscopy (TXAFS). The lattice contribution to the thermal conductivity is dominant, and its reduction is mainly ascribed to the increment of point defects after cobalt substitution. Furthermore, a lattice dynamic study shows that the Einstein temperature of atomic pairs is reduced after cobalt substitution, revealing that increasing local structure disorder and weakened bonding for each of the atomic pairs are achieved, which gives us a new perspective for understanding the behavior of lattice thermal conductivity.

6.
Chemosphere ; 197: 362-366, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29407806

RESUMEN

In this study, fly ash samples were collected from bag houses in a Chinese municipal solid waste incinerator (MSWI) and secondary fly ash (SFA) samples were collected from a high-temperature tubular electric furnace by thermal treatment of MSWI fly ash at 1050, 1100, 1150, 1200, and 1250 °C.We determined the speciation and atomic coordinates of lead in SFA using X-ray absorption spectroscopy (XAS) techniques. The results obtained by X-ray absorption near edge structure (XANES) spectra revealed that the mass fraction of PbO in MSWI fly ash was 57.9% (wt %) while PbCl2 and PbS were the dominant species in SFA. Extended X-ray absorption fine structure (EXAFS) data analysis indicated the atomic coordinates of Pb were proportional to the weights of PbCl2 and PbS, in good agreement with the XANES spectra. These findings highlight lead evaporation processes in the MSWI fly ash during heat treatment and provide a method for consistent speciation analysis of environmental samples using XAS.


Asunto(s)
Contaminantes Atmosféricos/análisis , Incineración/métodos , Plomo/análisis , Residuos Sólidos/análisis , Carbono/química , Ceniza del Carbón/química , Metales Pesados/análisis , Material Particulado/química , Eliminación de Residuos/métodos , Espectroscopía de Absorción de Rayos X , Rayos X
7.
Waste Manag ; 72: 218-226, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29169859

RESUMEN

A model based on feature objects (FOs) aided strategy was used to evaluate the methane generation from food waste by anaerobic digestion. The kinetics of feature objects was tested by the modified Gompertz model and the first-order kinetic model, and the first-order kinetic hydrolysis constants were used to estimate the reaction rate of homemade and actual food waste. The results showed that the methane yields of four feature objects were significantly different. The anaerobic digestion of homemade food waste and actual food waste had various methane yields and kinetic constants due to the different contents of FOs in food waste. Combining the kinetic equations with the multiple linear regression equation could well express the methane yield of food waste, as the R2 of food waste was more than 0.9. The predictive methane yields of the two actual food waste were 528.22 mL g-1 TS and 545.29 mL g-1 TS with the model, while the experimental values were 527.47 mL g-1 TS and 522.1 mL g-1 TS, respectively. The relative error between the experimental cumulative methane yields and the predicted cumulative methane yields were both less than 5%.


Asunto(s)
Alimentos , Metano/metabolismo , Residuos Sólidos , Anaerobiosis , Reactores Biológicos , Digestión , Cinética
8.
Exp Eye Res ; 160: 21-30, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28434813

RESUMEN

Teleost fish continues to grow their eyes throughout life with the body size. In Astatotilapia burtoni, the fish retina increases by adding new retinal cells at the ciliary marginal zone (CMZ) and in the outer nuclear layer (ONL). Cell proliferation at both sites exhibits a daily rhythm in number of dividing cells. To understand how this diurnal rhythm of new cell production is controlled in retinal progenitor cells, we studied the transcription pattern of clock genes in retina, including clock1a, clock1b, bmal1a (brain and muscle ARNT-Like), and per1b (period1b). We found that these genes have a strong diurnal rhythmic transcription during light-dark cycles but not in constant darkness. An oscillation in pcna transcription was also observed during light-dark cycles, but again not in constant darkness. Our results also indicate an association between Clock proteins and the upstream region of pcna (proliferating cellular nuclear antigen) gene. A luciferase reporter assay conducted in an inducible clock knockdown cell line further demonstrated that the mutation on predicted E-Boxes in pcna promoter region significantly attenuated the transcriptional activation induced by Clock protein. These results suggested that the diurnal rhythmic expression of clock genes in A. burtoni retina could be light dependent and might contribute to the daily regulation of the proliferation of the retina progenitors through key components of cell cycle machinery, for instance, pcna.


Asunto(s)
Proteínas CLOCK/genética , Regulación de la Expresión Génica , Antígeno Nuclear de Célula en Proliferación/genética , ARN/genética , Retina/metabolismo , Animales , Western Blotting , Proteínas CLOCK/biosíntesis , División Celular , Línea Celular , Proliferación Celular , Cíclidos , Ritmo Circadiano/fisiología , Inmunohistoquímica , Hibridación in Situ , Luz , Ratones , Modelos Animales , Fotoperiodo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Retina/citología , Células Madre/citología , Células Madre/metabolismo , Transcripción Genética
9.
ACS Appl Mater Interfaces ; 8(24): 15196-204, 2016 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-27135808

RESUMEN

We report remarkably enhanced thermoelectric performance of Te doped Cu2Se in midtemperature range. Through ball-milling process followed by spark plasma sintering (SPS), nanoscale Cu2Te clusters were embeded in the matrix of Cu2Se, inducing a drastic enhancement of thermoelectric performance by reducing the thermal conductivity without degrading the power factor. A large ZT value of 1.9 was achieved at 873 K for Cu2Se1.9Te0.1, which is about 2 times larger than that of the pure Cu2Se. The nanoscale heat management by Cu2Te nanoclusters in superionic conductors opens up an avenue for thermoelectric materials research.

10.
Phys Chem Chem Phys ; 18(21): 14580-7, 2016 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-27181423

RESUMEN

The misfit layered cobaltate thermoelectrics are good candidates for high temperature thermoelectric applications. Ca3Co4O9 is a typical compound of this family, which consists of rock salt Ca2CoO3 slabs alternating with hexagonal CoO2 slabs with a large lattice mismatch along the b axis. Each slab is 0.3-0.5 nm thick and shows an inherent structural heterogeneity at the nanoscale. The latter is a key parameter that affects the electrical transport and the heat flow in these misfit structured thermoelectrics. To clarify the physical origin of the thermoelectric performance of iron doped Ca3Co4O9 we combined X-ray near-edge absorption spectroscopy (XANES) and quantum modeling using density functional theory. In contrast to single-site doping, the iron doping first occurs at the Co1 site of the rock salt slab at low doping while at higher doping it prefers the Ca1 site of the rock salt slab. Doping at the Ca1 site modifies the electronic structure tuning the nanoscale structural heterogeneity. This mechanism may open a new route to optimizing the thermoelectric performance of misfit layered thermoelectrics.

11.
Bioresour Technol ; 198: 372-9, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26409107

RESUMEN

The anaerobic digestion (AD) of protein-rich substrates is generally inhibited by ammonia. In this study, ammonia-tolerant acclimation was exposed to a stepwise in situ ammonia stress during the continuous AD of solid residual kitchen waste by using a continuous stirred tank reactor with a 50 L active volume. The reactor worked well during the acclimation process, with an average daily biogas production of 58 L/d, an effluent soluble chemical oxygen demand of 7238 mg/L, a volatile fatty acid (VFA) content of 578 mg/L, and a VFA/alkalinity ratio of less than 0.4. Moreover, ammonia stress enhanced the activity of Coenzyme F420. The results of high-throughput 16S rDNA sequencing showed that ammonia stress increased the relative abundance of Firmicutes bacteria and hydrogenotrophic methanogens but decreased the abundance of acetotrophic methanogens. This microbial community shift was proposed to be an in situ response strategy for ammonia stress adaptation.


Asunto(s)
Amoníaco/farmacología , Anaerobiosis/efectos de los fármacos , Ácidos Grasos Volátiles/metabolismo , Aguas del Alcantarillado/microbiología , Bacterias/metabolismo , Biocombustibles/microbiología , Análisis de la Demanda Biológica de Oxígeno , Euryarchaeota/metabolismo , Metano/biosíntesis
12.
Phys Chem Chem Phys ; 17(17): 11229-33, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25829235

RESUMEN

Ga doped In2O3-based thermoelectric materials were prepared by spark plasma sintering (SPS) using sintered powders in the low temperature solid phase. The solubility of Ga in In2O3 is about 10 at%, much larger than other elements such as Ge, Ce, etc. The larger solubility of Ga allows us to optimize the thermal and electrical transport properties of Ga doped In2O3 in a wider window. While tuning the concentration of dopants, the thermoelectric performance of Ga doped In2O3 was enhanced through a synergistic approach combining band-gap engineering and phonon suppression. The power factor increases from ∼0.5 × 10(-4) to ∼9.6 × 10(-4) W mK(-2) at 700 °C while thermal conductivity reduces from ∼4 to ∼2 W mK(-1) at 700 °C in In1.9Ga0.1O3. The maximum ZT of 0.37, increased by a factor of 4 from the pristine In2O3, is achieved in In1.9Ga0.1O3 at 700 °C.

13.
Sci Rep ; 4: 7453, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25503313

RESUMEN

Peptide deformylase (PDF) is a prokaryotic enzyme that catalyzes the deformylation of nascent peptides generated during protein synthesis and water molecules play a key role in these hydrolases. Using X-ray absorption near edge spectroscopy (XANES) and ab initio calculations we accurately probe the local atomic environment of the metal ion binding in the active site of PDF at different pH values and with different metal ions. This new approach is an effective way to monitor existing correlations among functions and structural changes. We show for the first time that the enzymatic activity depends on pH values and metal ions via the bond length of the nearest coordinating water (Wat1) to the metal ion. Combining experimental and theoretical data we may claim that PDF exhibits an enhanced enzymatic activity only when the distance of the Wat1 molecule with the metal ion falls in the limited range from 2.15 to 2.55 Å.


Asunto(s)
Amidohidrolasas/química , Proteínas Bacterianas/química , Agua/química , Biocatálisis , Dominio Catalítico , Complejos de Coordinación/química , Leptospira/enzimología , Modelos Moleculares , Espectroscopía de Absorción de Rayos X , Zinc/química
14.
Electrophoresis ; 34(17): 2568-76, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23801369

RESUMEN

In this work, the influences of ionic liquid (IL) as a modifier on microemulsion microstructure and separation performance in MEEKC were investigated. Experimental results showed that synergetic effect between IL 1-butyl-3-methylimidazolium tetrafluoro-borate (BmimBF4 ) and surfactant SDS gave a decreased CMC. With increment of IL in microemulsion, negative ζ potential of the microdroplets reduced gradually. The influence of IL on the dimensions of microdroplet was complicated. At BmimBF4 less than 8 mM, IL made microemulsion droplet smaller in size. While at BmimBF4 more than 10 mM, the size increased and reached to a maximum value at 12 mM, where the microdroplets were larger than that without IL. After that, the micreodroplet size decreased again. Relative fluorescence intensity of the first vibration band of pyrene to the third one (I1 /I3 ) enhanced as IL was added to microemulsion, which indicated that this addition increased environmental polarity in the inner core of microdroplets. Prednisone, hydrocortisone, prednisolone, hydrocortisone acetate, cortisone acetate, prednisolone acetate, and triamcinolone acetonide were analyzed with MEEKC modified with IL to evaluate the separation performance. Cortisone acetate and prednisolone acetate could not be separated at all in typical microemulsion. The seven analytes could be separated by the addition of 10 mM BmimBF4 into the microemulsion system. The method has been used for analysis of corticosteroids in cosmetic samples with simple extraction; the recoveries for seven analytes were between 86 and 114%. This method provides accuracy, reproducibility, pretreatment simplicity, and could be applied to the quality control of cosmetics.


Asunto(s)
Corticoesteroides/análisis , Cromatografía Capilar Electrocinética Micelar/métodos , Líquidos Iónicos/química , Cromatografía Capilar Electrocinética Micelar/instrumentación , Cosméticos/química , Emulsiones/química , Imidazoles/química , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Dodecil Sulfato de Sodio/química
15.
J Chromatogr A ; 1245: 190-8, 2012 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-22633065

RESUMEN

A simple, green, and novel approach to prepare polymeric micelle with amphiphilic random copolymer P (MMA-co-MAA) via neutralization in aqueous medium has been developed, and the polymeric micelle was firstly applied as a pseudostationary phase (PSP) in electrokinetic chromatography (EKC) in the present work. Three structurally similar corticosteroids namely hydrocortisone, prednisolone, and prednisone were separated with EKC using polymeric micelle as PSP to assess the separation performance. The effects of polymeric concentration and pH on micellar microstructure including size, morphology, surface charge density and EKC performances have been investigated. TEM showed that amphiphilic random copolymers were self-assembled via neutralization to form micelles with well-defined size and shape. The size and shape of the micelle depended on the P (MMA-co-MAA) concentration and pH. At the concentration of 0.048 mM and pH 9.2, the polymeric micelles were of monodispersity and perfect spheres. DLS showed the size of micelle was almost equal as polymer concentration in the range of 0.0096-0.048 mM, and then enlarged sharply at the concentration larger than 0.048 mM. However, the zeta potentials of micelle were nearly unchanged. The polymer concentration is also the key parameter for EKC separation. Under the optimum conditions, three analytes could be baseline separated within 7.4 min. Compared with typical MEKC, MEEKC, and MEKC modified with IL ([Bmim]BF4), the developed method was more rapid, efficient, and higher selective. The separation mechanism using polymeric micelle as PSP was reverse-phase interaction. The actual cosmetic samples were analyzed with recoveries between 97.3% and 113%.


Asunto(s)
Cromatografía Capilar Electrocinética Micelar/instrumentación , Polímeros/química , Adsorción , Cromatografía Capilar Electrocinética Micelar/métodos , Micelas
16.
Biochem Biophys Res Commun ; 419(1): 1-6, 2012 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-22321394

RESUMEN

Duchenne muscular dystrophy is the most prevalent inheritable muscle disease. Transplantation of autologous stem cells with gene direction is an ideal therapeutic approach for the disease. The current study aimed to investigate the restoration of myofibers in mdx mice after mdx bone marrow-derived mesenchymal stem cell (mMSC) transplantation with human microdystrophin delivery. Possible mechanisms of action were also studied. In our research, mMSCs were successfully transduced by retrovirus carrying a functional human microdystrophin gene. Transplantation of transduced mMSCs enabled persistent dystrophin restoration in the skeletal muscle of mdx mice up to the 12th week after transplantation. Simultaneous coexpression of human microdystrophin and desmin showed that implanted mMSCs are capable of long-term survival as muscle satellite cells.


Asunto(s)
Distrofina/genética , Terapia Genética/métodos , Trasplante de Células Madre Mesenquimatosas/métodos , Fibras Musculares Esqueléticas/fisiología , Distrofia Muscular de Duchenne/terapia , Células Satélite del Músculo Esquelético/fisiología , Animales , Modelos Animales de Enfermedad , Técnicas de Transferencia de Gen , Humanos , Ratones , Fibras Musculares Esqueléticas/metabolismo , Retroviridae , Células Satélite del Músculo Esquelético/metabolismo
17.
Chemosphere ; 87(3): 211-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22225704

RESUMEN

In this study, we investigated the Cr(VI) uptake mechanism in an indigenous Cr(VI)-tolerant bacterial strain -Bacillus cereus through batch and microscopic experiments. We found that both the cells and the supernatant collected from B. cereus cultivation could reduce Cr(VI). The valence state analysis revealed the complete transformation from Cr(VI) into Cr(III) by living B. cereus. Further X-ray absorption fine structure and Fourier transform infrared analyses showed that the reduced Cr(III) was coordinated with carboxyl and amido functional groups from either the cells or supernatant. Scanning electron microscopy and atomic force microscopy observation showed that noticeable Cr(III) precipitates were accumulated on bacterial surfaces. However, Cr(III) could also be detected in bacterial inner portions by using transmission electron microscopy thin section analysis coupled with energy dispersive X-ray spectroscopy. Through quantitative analysis of chromium distribution, we determined the binding ratio of Cr(III) in supernatant, cell debris and cytoplasm as 22%, 54% and 24%, respectively. Finally, we further discussed the role of bacterium-origin soluble organic molecules to the remediation of Cr(VI) pollutants.


Asunto(s)
Bacillus cereus/metabolismo , Cromo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Adaptación Fisiológica , Bacillus cereus/fisiología , Biodegradación Ambiental , Eliminación de Residuos Líquidos/métodos
18.
Se Pu ; 29(2): 131-6, 2011 Feb.
Artículo en Chino | MEDLINE | ID: mdl-21598512

RESUMEN

The effects of ionic liquids on micellar microstructures and separation performance in micellar electrokinetic chromatography (MEKC) were investigated. The experimental results showed that the addition of ionic liquids into micellar system would result in a decreased micellar surface charge density, an enlarged size of micelle and a slight enhancement of the polarity in the inner core of micelle. Prednisone, hydrocortisone and prednisolone were analyzed with MEKC to evaluate the separation performance. Hydrocortisone and prednisolone could not be separated in sodium lauryl sulfate (SDS) micellar system. However, the three analytes could be baseline separated in the mixed system of ionic liquids and SDS (20 mmol/L SDS-10 mmol/L 1-butyl-3-methyl imidazolium tetrafluoroborate-50 mmol/L borax, pH 8.4) within 17 min. Notably, the linearities of the three analytes ranged from 2 to 100 mg/L and the detection limits based on the ratio of signal to noise of 3 were 1.0, 1.1 and 1.0 mg/L for prednisone, hydrocortisone and prednisolone, respectively. The method has been used in the analysis of corticosteroids in cosmetic samples. The recoveries for the three analytes were between 95. 1% and 117%. This method has the advantages of simple pretreatment, high accuracy, good reproducibility, and can be applied to the quality control of cosmetics.

19.
Basic Clin Pharmacol Toxicol ; 109(1): 42-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21306565

RESUMEN

Lamotrigine (LTG) is a commonly used antiepileptic drug. However, the use of LTG is limited because of its cutaneous adverse drug reactions (cADRs) ranging from mild maculopapular eruption (MPE) to severe Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). A strong association between HLA-B*1502 and carbamazepine-induced SJS/TEN has been identified in Chinese and Thai. Although three of seven cases with HLA-B*1502 have been reported in LTG-induced SJS/TEN so far, the relationship between HLA-B*1502 and LTG-induced SJS/TEN needs further investigation. It is also unclear whether there is a specific genetic marker associated with LTG-induced MPE in Chinese. In this study, we genotyped 43 Han Chinese patients treated with LTG (14 cases with LTG-induced cADRs and 29 LTG-tolerant controls), using PCR-SSP for HLA-B*1502 testing and low-resolution genotyping, as well as sequencing for four-digit genotyping. The two cases with SJS were negative for HLA-B*1502, with B1301/1301 and 4601/5610, respectively. Combining the data with previous studies, there was no significant difference in the frequency of subjects with HLA-B*1502 between the LTG-induced SJS/TEN group and the LTG-tolerant group (p = 0.08, OR 4.23, 95% CI 0.94-18.97). In the MPE group, only one was positive for HLA-B*1502. There was no significant difference in the frequency of a specific HLA-B allele between the MPE group and the LTG-tolerant group either. In this study, no significant association between HLA-B*1502 and LTG-induced SJS or MPE was found. Given the small sample size and only HLA-B locus genotyping, further large-scale studies are required to explore genetic associations with LTG-induced cADRs.


Asunto(s)
Anticonvulsivantes/efectos adversos , Erupciones por Medicamentos/etiología , Antígenos HLA-B/genética , Triazinas/efectos adversos , Adolescente , Anciano , Alelos , Pueblo Asiatico/genética , Secuencia de Bases , Niño , Preescolar , China , Cartilla de ADN , Erupciones por Medicamentos/genética , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Lamotrigina , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Adulto Joven
20.
J Mol Neurosci ; 44(2): 115-21, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21271300

RESUMEN

Voltage-gated sodium channel α-subunit type III (Na(v)1.3) is mainly expressed in the central nervous system and is associated with neurological disorders. The expression of mouse Scn3a product (Na(v)1.3) mainly occurs in embryonic and early postnatal brain but not in adult brain. Here, we report for the first time the identification and characterization of the mouse Scn3a gene promoter region and regulation of the promoter activity by GC box and CpG methylation. Luciferase assay showed that the promoter region F1.2 (nt -1,049 to +157) had significantly higher activity in PC12 cells, comparing with that in SH-SY5Y cells and HEK293 cells. A stepwise 5' truncation of the promoter region found that the minimal functional promoter located within the region nt -168 to +157. Deletion of a GC box (nt -254 to -258) in the mouse Scn3a promoter decreased the promoter activity. CpG methylation of the F1.2 without the GC box completely repressed the promoter activity, suggesting that the GC box is a critical element in the CpG-methylated Scn3a promoter. These results suggest that the GC box and CpG methylation might play important roles in regulating mouse Scn3a gene expression.


Asunto(s)
Islas de CpG , Metilación de ADN , Fosfatos de Dinucleósidos/metabolismo , Regiones Promotoras Genéticas/genética , Canales de Sodio/genética , Animales , Línea Celular Tumoral , Regulación de la Expresión Génica , Humanos , Ratones , Mutagénesis Sitio-Dirigida , Canal de Sodio Activado por Voltaje NAV1.3
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