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1.
Medicine (Baltimore) ; 102(44): e35712, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37933065

RESUMO

This study aims to investigate the causal effect of Alzheimer disease on thyroiditis using medical English and the Nature journal style. Genome-wide association data for Alzheimer disease and thyroiditis were obtained from the Mendelian Randomization (MR) platform. Single nucleotide polymorphisms (SNPs) significantly associated with Alzheimer disease were identified and used as instrumental variables (IVs) to examine the causal relationship between Alzheimer disease and thyroiditis, employing a 2-sample MR study design. Five statistical methods, including inverse-variance weighted (IVW) method, weighted median estimation, simple mode estimation, weighted mode estimation, and MR-Egger regression, were utilized. In the study, 13 single nucleotide polymorphisms (SNPs) were identified to be significantly associated with Alzheimer disease (P < 5 × 10-8, linkage disequilibrium r2 < 0.001). Upon evaluation using different methods, a consistent association between Alzheimer disease and thyroiditis was observed inverse variance-weighted method [IVW]: odds ratio [OR] 1.32, 95% confidence interval [CI] 1.01-1.72; weighted median estimator: OR 1.32, 95% CI 1.01-1.72; Mendelian randomization Egger regression: OR 1.29, 95% CI 0.92-1.81), indicating a positive correlation between Alzheimer disease and increased risk of thyroiditis. There was no evidence suggesting that the observed causal relationship between Alzheimer disease and thyroiditis risk could be influenced by pleiotropy (Mendelian randomization Egger intercept 0.0058, P = .88. Our MR analysis reveals causal association of Alzheimer disease and thyroiditis, despite observational studies reporting an association between Alzheimer disease and thyroiditis.


Assuntos
Doença de Alzheimer , Estudo de Associação Genômica Ampla , Humanos , Análise da Randomização Mendeliana/métodos , Causalidade , Polimorfismo de Nucleotídeo Único
2.
Clin Res Hepatol Gastroenterol ; 47(8): 102200, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37643692

RESUMO

Pancreatic cancer (PAC) remains one of the most lethal malignant neoplasms, which is diagnosed at an advanced stage and thus lose the chance for curative resection. Here, we further probed PAC with a comprehensive multi-omics approach. Using single-cell RNA sequencing, we provided an integrated analysis of ductal cell subpopulations over the Leiden algorithm to identify two mian subcluster: S100A6 + cells and FXYD2 + cells. The gene set enrichment analysis results show that the two subtypes focused on different pathways related to tumor development. Furthermore, we integrated bulk and single-cell RNA sequencing datasets to generate and validate the prognostic signatures of the overall survival (OS) in PAC patients and S100A6 + cells were significantly enriched in high-risk groups which had a poor prognosis. Collectively, this research expands our understanding of ductal cell and provides a new reliable prognosis signature in PAC.

3.
Anal Bioanal Chem ; 413(7): 1827-1836, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33481047

RESUMO

As a nonspecific phosphomonoesterase, alkaline phosphatase (ALP) plays a pivotal role in tissue mineralization and osteogenesis which is an important biomarker for the clinical diagnosis of bone and hepatobiliary diseases. Herein, we described a novel electrochemical method that used aminoferrocene (AFC) as an electroactive probe for the ALP activity detection. In the condition with imidazole and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC), the AFC probe could be directly labeled on single-stranded DNA (ssDNA) by one-step conjugation. Specifically, thiolated ssDNA at 3'-terminals was modified to the electrode surface through Au-S bond. In the condition without ALP, AFC could be labeled on ssDNA by conjugating with phosphate groups. In the presence of ALP, phosphate groups were catalyzed to be removed from the 5'-terminal of ssDNA. The AFC probe cannot be labeled on ssDNA. Thus, the electrochemical detection of ALP activity was achieved. Under optimal conditions, the strategy presented a good linear relationship between current intensity and ALP concentration in the range of 20 to 100 mU/mL with the limit of detection (LOD) of 1.48 mU/mL. More importantly, the approach rendered high selectivity and satisfactory applicability for ALP activity detection. In addition, this method has merits of ease of operation, low cost, and environmental friendliness. Thus, this strategy presents great potential for ALP activity detection in practical applications. An easy, sensitive and reliable strategy was developed for the detection of alkaline phosphatase activity via electrochemical "Signal off".


Assuntos
Fosfatase Alcalina/análise , DNA de Cadeia Simples/análise , Eletroquímica/métodos , Enzimas/química , Compostos Ferrosos/química , Metalocenos/química , Fosfatase Alcalina/sangue , Animais , Técnicas Biossensoriais , Catálise , Bovinos , DNA de Cadeia Simples/sangue , Enzimas/sangue , Compostos Ferrosos/sangue , Glucose Oxidase/análise , Ouro/química , Humanos , Imidazóis/análise , Limite de Detecção , Metalocenos/sangue , Fosforilação , Reprodutibilidade dos Testes , Soro/química , Soroalbumina Bovina/análise , Enxofre/química
4.
PLoS One ; 11(8): e0160079, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27479072

RESUMO

Sweet state is a basic physiological sensation of humans and other mammals which is mediated by the broadly acting sweet taste receptor-the heterodimer of Tas1r2 (taste receptor type 1 member 2) and Tas1r3 (taste receptor type 1 member 3). Various sweeteners interact with either Tas1r2 or Tas1r3 and then activate the receptor. In this study, we cloned, expressed and functionally characterized the taste receptor Tas1r2 from a species of Old World monkeys, the rhesus monkey. Paired with the human TAS1R3, it was shown that the rhesus monkey Tas1r2 could respond to natural sugars, amino acids and their derivates. Furthermore, similar to human TAS1R2, rhesus monkey Tas1r2 could respond to artificial sweeteners and sweet-tasting proteins. However, the responses induced by rhesus monkey Tas1r2 could not be inhibited by the sweet inhibitor amiloride. Moreover, we found a species-dependent activation of the Tas1r2 monomeric receptors of human, rhesus monkey and squirrel monkey but not mouse by an intense sweetener perillartine. Molecular modeling and sequence analysis indicate that the receptor has the conserved domains and ligand-specific interactive residues, which have been identified in the characterized sweet taste receptors up to now. This is the first report of the functional characterization of sweet taste receptors from an Old World monkey species.


Assuntos
Cicloexenos/metabolismo , Macaca mulatta/genética , Monoterpenos/metabolismo , Oximas/metabolismo , Receptores Acoplados a Proteínas G/genética , Edulcorantes/metabolismo , Amilorida/química , Amilorida/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Cicloexenos/química , Células HEK293 , Humanos , Macaca mulatta/metabolismo , Camundongos , Modelos Moleculares , Monoterpenos/química , Oximas/química , Ligação Proteica , Estrutura Terciária de Proteína , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Saimiri/genética , Saimiri/metabolismo , Alinhamento de Sequência , Especificidade da Espécie , Edulcorantes/química , Ativação Transcricional/genética
5.
Talanta ; 71(2): 778-83, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19071373

RESUMO

Sequential extraction procedures were widely applied for speciation of radioactive elements. In this study, the sequential extraction procedure developed by Martínez-Aguirre was employed for quantification of different chemical forms of thorium in the soil. The total amount of thorium in contaminated soil was much higher by four-fold than the local background value. The soil properties affect the amount of thorium and distribution of fractions in contaminated soil. Results showed that the proportion of thorium in soils from Baotou was found as the residual fraction (F5+F6)>absorbed fraction (F3), coprecipitated fraction (F4)>carbonates fraction (F2) and exchangeable fraction (F1) that could be available to plants. The recovery, calculated by ratio of the sum of the six fractions to the pseudo-total content of thorium, was in the range from 96% to 110%. A comparison was carried out between the sequential extraction and the single extraction to evaluate the selectivity of the extractants. It was found that the amount of thorium of absorbed fraction (F3) was higher in the single extraction than that estimated in the sequential extraction, possibly duo to transform of the labile form. While for non-residual fraction analysis, the single extraction scheme was a desirable alternative to the sequential extraction procedure. According to correlativity analysis of various fractions, it might be predicted that how the non-residual fractions of thorium were directionally transformed into interrelated fractions under the changes of conditions.

6.
Talanta ; 67(5): 968-74, 2005 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-18970266

RESUMO

In this work, a method was developed for determination of ultra-trace levels of Cd in tea samples by atomic fluorescence spectrometry (AFS). A flow injection solid phase extraction (FI-SPE) separation and preconcentration technique, to on-line couple with a sequential injection hydride generation (SI-HG) technique is employed in this study. Cd was preconcentrated on the SPE column, which was made from a neutral extractant named Cyanex 923, while other matrix ions or interfering ions were completely or mostly separated off. Conditions for the SPE separation and preconcentration, as well as conditions for the HG technique, were studied. Due to the separation of interfering elements, Cd hydride generation efficiency could be greatly enhanced with the sole presence of Co(2+) with a concentration of 200mugL(-1), which is much lower than those in other works previously reported. Interferences on both the Cd separation and preconcentration, and Cd hydride generation (HG) were investigated; it showed that both the separation and preconcentration system, and the HG system had a strong anti-interference ability. The SPE column could be repeatedly used at least 400 times, a R.S.D. of 0.97% was obtained for 6 measurements of Cd with 0.2mugL(-1) and a correlation coefficiency of 1.0000 was obtained for the measurement of a series of solutions with Cd concentrations from 0.1 to 2mugL(-1). The method has a low detection limit of 10.8ngL(-1) for a 25mL solution and was successfully validated by using two tea standard reference materials (GBW08513 and GBW07605).

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