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1.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(3): 351-355, 2024 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-38448028

RESUMO

OBJECTIVE: To explore the clinical phenotype and genetic characteristics of a child with Hypotrichosis 14. METHODS: A child who had presented at the Henan Provincial People's Hospital on May 4, 2020 due to hair thinning was selected as the study subject. Clinical data of the child was collected. Peripheral venous blood samples were collected from the child and her parents. Genomic DNA was extracted and subjected to whole exome sequencing. Candidate variants were validated by Sanger sequencing and bioinformatic analysis. RESULTS: The child, a 5-year-old female, had presented with thin, soft lanugo-like hair which was easy to fall off. The child was found to harbor compound heterozygous missense variants of the LSS gene, namely c.1609G>A (p.V537M) in exon 17 and c.802T>G (p.F268V) in exon 8, which were respectively inherited from her father and mother. Both variant sites were highly conserved, though based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were rated as variants of unknown significance (PM2_Supporting+PP3+PP4). CONCLUSION: The c.1609G>A (p.V537M) and c.802T>G (p.F268V) compound heterozygous variants of the LSS gene probably underlay the clinical phenotype in this patient.


Assuntos
Alopecia , Biologia Computacional , Hipotricose , Humanos , Criança , Feminino , Pré-Escolar , Éxons , Genômica
2.
Phys Chem Chem Phys ; 25(12): 8532-8543, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36883610

RESUMO

Although introducing an alkoxy group is one of the most popular methods to suppress the interfacial charge recombination process of dye-sensitized solar cells, understanding of its effects is still limited and a microscopic picture of the alkoxy effects is lacking. Two ullazine dyes with distinct alkoxy chains at the donor part are used to investigate the effects of the alkoxy group on the adsorption, dye aggregation and charge recombination process in our study. Different from the usual assumption, we find that alkoxy chains can not only play a shielding role, but can also assist dye adsorption and inhibit the charge recombination process more effectively by covering the TiO2 surface. We also find that the existence of alkyl chains can well inhibit the aggregation of dyes and reduce intermolecular electron transfer. Furthermore, an important structural feature at the interface, the Ti-O interaction between the oxygen atom of the alkoxy group and the Ti atom of the surface is also found to contribute substantially to the interface stability. New insights into the effects of the alkoxy group on auxiliary adsorption and inhibiting charge recombination through reducing the recombination sites pave the way for rational design of sensitizers with high performance.

3.
J Chromatogr Sci ; 53(8): 1333-40, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25838166

RESUMO

A method based on matrix solid-phase dispersion and high-performance liquid chromatography was applied to the determination of four Sudan red residues in sausage. The proposed method required only 0.5 g sample. The neutral alumina was used as the dispersant sorbent while n-hexane containing 10% (v/v) acetone was used as the eluting solvent. The recoveries in samples ranged from 76.4 to 111.0% and relative standard deviations were <10.2% with different spiked levels of 0.05-1.50 mg kg(-1). Detection and quantification limits were 5-19 and 18-39 µg kg(-1), respectively, with linear calibration curves extending up to 2.50 mg g(-1). The results demonstrate that the method can be successfully applied with acceptable recoveries to a broad range of target analytes within a diverse range of sausage.


Assuntos
Compostos Azo/análise , Cromatografia Líquida de Alta Pressão/métodos , Corantes/análise , Extração em Fase Sólida/métodos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Genet Test Mol Biomarkers ; 18(4): 257-60, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24444085

RESUMO

OBJECTIVE: Toll-like receptor 4 (TLR4) is an important candidate gene for mediating the susceptibility to type 2 diabetes mellitus (T2DM). The purpose of this study was to investigate the association between the TLR4 gene polymorphisms and T2DM susceptibility. METHODS: A total of 671 T2DM patients and 677 healthy controls were recruited in this study. The created restriction site-polymerase chain reaction and DNA sequencing methods have been used to analyze the TLR4 gene polymorphisms. RESULTS: One novel genetic polymorphism (g.14461A>G) was found. Our data indicated that the g.14461A>G genetic polymorphism was significantly associated with the increased susceptibility to T2DM in a homozygote comparison (GG vs. AA: odds ratio [OR]=2.09, 95% confidence interval [CI] 1.44-3.04, p<0.001), dominant model (GG/AG vs. AA: OR=1.27, 95% CI 1.03-1.57, p=0.028), recessive model (GG vs. AG/AA: OR=1.98, 95% CI 1.39-2.83, p<0.001), and allele contrast (G vs. A: OR=1.33, 95% CI 1.13-1.57, p=0.001). The allele-G might be the risk allele for enhancing the susceptibility to T2DM. CONCLUSION: These preliminary findings suggest that the g.14461A>G genetic polymorphism of the TLR4 gene is potentially related to the susceptibility to T2DM in the studied population.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Polimorfismo Genético , Receptor 4 Toll-Like/genética , Adulto , Idoso , Alelos , Sequência de Bases , Estudos de Casos e Controles , China , Primers do DNA , Feminino , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
7.
PLoS One ; 8(5): e62377, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23667473

RESUMO

Keloid is benign fibroproliferative dermal tumors with unknown etiology. Recently, a genome-wide association study (GWAS) in Japanese population has identified 3 susceptibility loci (rs873549 at 1q41, rs940187 and rs1511412 at 3q22.3, rs8032158 at 15p21.3) for keloid. In order to examine whether these susceptibility loci are associated with keloid in the Chinese Han population, twelve previously reported SNPs were selected for replication in 714 cases and 2,944 controls by using Sequenom MassArray system. We found three SNPs in two regions showed significant association with keloid in the Chinese Han population: 1q41 (rs873549, P = 3.03×10(-33), OR = 2.05, 95% CI: 1.82-2.31 and rs1442440, P = 9.85×10(-18), OR = 0.56, 95% CI: 0.49-0.64, respectively) and 15q21.3 (rs2271289 located in NEDD4, P = 1.02×10(-11), OR = 0.66, 95% CI: 0.58-0.74). We also detected one risk haplotype AG (P = 1.36×10(-31), OR = 2.02) and two protective haplotypes of GA and AA (GA, P = 1.94×10(-19), OR = 0.53, AA, P = 0.00043, OR = 0.78, respectively) from the two SNPs (rs873549 and rs1442440). Our study confirmed two previously reported loci 1q41 and 15q21.3 for keloid in the Chinese Han population, which suggested the common genetic factor predisposing to the development of keloid shared by the Chinese Han and Japanese populations.


Assuntos
Povo Asiático/etnologia , Povo Asiático/genética , Etnicidade/genética , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Queloide/genética , Adulto , Feminino , Haplótipos/genética , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
8.
Anal Chem ; 85(9): 4546-53, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23531235

RESUMO

In situ probing protein-particle interactions and activities of proteins on colloidal nanoparticle (NP) surfaces is a long-standing key challenge in understanding the nanobio interfaces and virtually important for a variety of biological and biomedical applications. The interactions of NPs with proteins, for instance, are known to form NP bioconjugates or protein coronas; protein surface immobilization and molecular layer-by-layer deposition techniques are widely used, but a clear understanding of the confinement effect on protein activity by molecular coating, at the monolayer level, remains poorly understood. We explore here a novel approach, using colloidal plasmonic nanocomplexes coated with glucose oxidase (GOx) as self-sensing nanoprobes for in situ optical probing of surface-confined enzymatic activity, which is at least 1-2 orders of magnitude more sensitive than standard colorimetric assays for detecting GOx activity. We found that enzymatic activity of monolayer-confined GOx on colloidal NPs was significantly enhanced as compared with free GOx (also proved by conformational changes from circular dichroism studies), with a low apparent Michaelis-Menten constant Km of ~0.115 mM and high turnover kcat/Km of ~8394 M(-1)·s(-1); compared with the "anchored-type" suspending GOx, the outmost polyelectrolyte monolayer-protected "sandwiched-type" GOx exhibits significantly improved enzymatic activities toward higher temperatures and wider pH range. This finding is of fundamental important and instructive for safe use of such nanomaterials for bioapplications.


Assuntos
Glucose Oxidase/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Prata/química , Coloides/química , Coloides/metabolismo , Ativação Enzimática , Glucose Oxidase/química , Ouro/metabolismo , Prata/metabolismo , Propriedades de Superfície
9.
Nanoscale ; 4(22): 6974-80, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23023515

RESUMO

As a simple and flexible 2D platform, the water-air interface is envisioned as an environmentally-friendly approach to prepare ultrathin free-standing nanomembranes (FNMs) of monolayered nanoparticles of interest via interfacial self-assembly. However, attempts so far have been rather rare due to the lack of efficient methods. In this article, we report on a facile and general strategy for fabrication of a family of noble metal-based FNMs by a simple and reagentless interfacial self-assembly tactics to prepare functional (plasmonic or catalytic) FNMs, such as Au, Ag, Pd, Pt-FNMs and their bimetallic hybrids, Ag/Au-FNMs and Pd/Pt-FNMs. The organic solvent-free process, varying somewhat from metal to metal only in precursors, reducing agents and dosage of reagents used, is found to be a general phenomenon and ligand-independent (irrespective of the monolayer quality of the resulting FNMs), allowing the growth of high-quality noble metal-based FNMs with well-defined nanoparticulate and monolayer morphology as large as several square centimeters. Heat treatment (boiling) is performed to accelerate the formation of FNMs within 15 min. More significantly, the as-prepared plasmonic Au-FNMs acting as a SERS substrate show a superior activity; whereas the resulting catalytic Pd-FNMs, except for their excellent ethanol electrooxidation performance, exhibit higher electrocatalytic activity for formic acid oxidation than commercial catalysts.

10.
Nat Genet ; 44(10): 1156-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22983302

RESUMO

Disseminated superficial actinic porokeratosis (DSAP) is an autosomal dominantly inherited epidermal keratinization disorder whose etiology remains unclear. We performed exome sequencing in one unaffected and two affected individuals from a DSAP family. The mevalonate kinase gene (MVK) emerged as the only candidate gene located in previously defined linkage regions after filtering against existing SNP databases, eight HapMap exomes and 1000 Genomes Project data and taking into consideration the functional implications of the mutations. Sanger sequencing in 57 individuals with familial DSAP and 25 individuals with sporadic DSAP identified MVK mutations in 33% and 16% of these individuals (cases), respectively. All 14 MVK mutations identified in our study were absent in 676 individuals without DSAP. Our functional studies in cultured primary keratinocytes suggest that MVK has a role in regulating calcium-induced keratinocyte differentiation and could protect keratinocytes from apoptosis induced by type A ultraviolet radiation. Our results should help advance the understanding of DSAP pathogenesis.


Assuntos
Exoma , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Mutação Puntual , Poroceratose/genética , Apoptose , Estudos de Casos e Controles , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Humanos , Queratinócitos/fisiologia , Masculino , Linhagem , Poroceratose/patologia , Sítios de Splice de RNA
11.
J Chromatogr Sci ; 50(2): 131-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22298763

RESUMO

Matrix solid-phase dispersion extraction was applied to the extraction of sulfadiazine, sulfamerazine, and sulfamethazine from human and animal bloods. The separation and determination of the analytes were carried out by high-performance liquid chromatography. The effects of the types of the dispersion adsorbents and elution solvents were investigated, and the highest recovery was obtained when diatomaceous earth was used as the dispersion adsorbent, while acetone was used as the elution solvent. Under the optimal conditions, the linear range for determining the sulfonamides in blood samples was 0.020-10.0 µg/mL, and the average recoveries of the three sulfonamides were higher than 87.5%.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodos , Sulfonamidas/sangue , Espectrofotometria Ultravioleta
12.
Adv Mater ; 24(12): 1594-7, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22351595

RESUMO

Macroscopic free-standing Pd and Pd/Pt bimetallic monolayer nanomembranes (Pd- and Pd/Pt-FNMs) derived from the spontaneous self-assembly of the as-produced Pd NPs and Pd/Pt bimetallic NPs at the water-air interface within 15 min are fabricated, respectively. The one-step method allows the growth of high-quality Pd-based FNMs with well-defined monolayer morphology, which exhibit significantly higher electrocatalytic activity for methanol/ethanol oxidation than commercial catalysts.


Assuntos
Etanol/química , Membranas Artificiais , Metanol/química , Nanoestruturas/química , Nanotecnologia/métodos , Paládio/química , Catálise , Modelos Moleculares , Conformação Molecular , Oxirredução , Platina/química
13.
J Sep Sci ; 34(9): 1069-75, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21416601

RESUMO

Headspace single drop microextraction (HS-SDME) coupled with microwave extraction (ME) was developed and applied to the extraction of the essential oil from dried Syzygium aromaticum (L.) Merr. et Perry and Cuminum cyminum L. The operational parameters, such as microdrop volume, microwave absorption medium (MAM), extraction time, and microwave power were optimized. Ten microliters of decane was used as the microextraction solvent. Ionic liquid and carbonyl iron powder were used as MAM. The extraction time was less than 7 min at the microwave power of 440 W. The proposed method was compared with hydrodistillation (HD). There were no obvious differences in the constituents of essential oils obtained by the two methods.


Assuntos
Fracionamento Químico/métodos , Cuminum/química , Myrtaceae/química , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Fracionamento Químico/instrumentação , Micro-Ondas , Óleos Voláteis/análise
14.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(28): 2707-11, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20810325

RESUMO

The arctiin and arctigenin in the fruit of Arctium lappa L. were extracted by matrix solid-phase dispersion (MSPD) and determined by high-performance liquid chromatography (HPLC) with fluorescence detection. The experimental conditions for the MSPD were optimized. Silica gel was selected as dispersion adsorbent and methanol as elution solvent. The calibration curve showed good relationship (r>0.9998) in the concentration range of 0.010-5.0µgmL(-1) for arctiin and 0.025-7.5µgmL(-1) for arctigenin. The recoveries were between 74.4% and 100%. The proposed method consumed less sample, time and solvent compared with conventional methods, including ultrasonic and Soxhlet extraction.


Assuntos
Arctium/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Frutas/química , Furanos/análise , Glucosídeos/análise , Lignanas/análise , Extração em Fase Sólida/métodos , Adsorção , Furanos/química , Glucosídeos/química , Lignanas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência
15.
J Sep Sci ; 32(20): 3544-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19764052

RESUMO

Ionic liquid was used as microwave absorption medium and applied to the extraction of essential oils from dried fruits of the Illicium verum Hook. f. and Cuminum cyminum L. by microwave-assisted extraction. The extraction time is less than 15 min at the microwave power of 440 W. The constituents of essential oils obtained by the proposed method were compared with those obtained by hydrodistillation. There is no obvious difference in the constituents of essential oils obtained by the two methods.


Assuntos
Cuminum/química , Illicium/química , Líquidos Iônicos/química , Micro-Ondas , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Absorção , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/química
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