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1.
J Am Chem Soc ; 145(8): 4683-4690, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36795912

RESUMEN

The valleytronic state found in group-VI transition-metal dichalcogenides such as MoS2 has attracted immense interest since its valley degree of freedom could be used as an information carrier. However, valleytronic applications require spontaneous valley polarization. Such an electronic state is predicted to be accessible in a new ferroic family of materials, i.e., ferrovalley materials, which features the coexistence of spontaneous spin and valley polarization. Although many atomic monolayer materials with hexagonal lattices have been predicted to be ferrovalley materials, no bulk ferrovalley material candidates have been reported or proposed. Here, we show that a new non-centrosymmetric van der Waals (vdW) semiconductor Cr0.32Ga0.68Te2.33, with intrinsic ferromagnetism, is a possible candidate for bulk ferrovalley material. This material exhibits several remarkable characteristics: (i) it forms a natural heterostructure between vdW gaps, a quasi-two-dimensional (2D) semiconducting Te layer with a honeycomb lattice stacked on the 2D ferromagnetic slab comprised of the (Cr, Ga)-Te layers, and (ii) the 2D Te honeycomb lattice yields a valley-like electronic structure near the Fermi level, which, in combination with inversion symmetry breaking, ferromagnetism, and strong spin-orbit coupling contributed by heavy Te element, creates a possible bulk spin-valley locked electronic state with valley polarization as suggested by our DFT calculations. Further, this material can also be easily exfoliated to 2D atomically thin layers. Therefore, this material offers a unique platform to explore the physics of valleytronic states with spontaneous spin and valley polarization in both bulk and 2D atomic crystals.

2.
BMC Public Health ; 23(1): 1791, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710220

RESUMEN

BACKGROUND: Overweight and obesity have become major public health concerns worldwide. Persistent stress can activate the human hypothalamic‒pituitary‒adrenal axis (HPA) and increase the intake of "self-rewarding food", thereby raising the incidence of obesity. Health care workers (HCWs) experience higher workloads and mental stress than workers in many other industries, which may put them at increased risk for overweight/obesity. However, few studies have been carried out on overweight and obesity among HCWs in China, and the overall scenario and behind-the-scenes factors of their overweight and obesity are unknown. The aim of this study is to understand the epidemic of overweight and obesity and risk factors among Chinese HCWs. METHODS: Based on a cross-sectional web survey design, 23,234 HCWs from 100 health institutions in 5 provinces/autonomous regions/municipalities across China were sampled to answer a self-administered questionnaire that was purposely developed using a multi-staged clustered random-sampling method. Chi-square test and ANOVA were performed to compare variables between two or more groups. Univariate analyses were conducted to identify the influence of self-reported persistent stress and/or recurrent anxiety/depressed mood on lifestyle behaviors. A multivariate binary logistic regression model was used to analyse the risk factors of overweight/obesity. RESULTS: Among the respondents, 34.26% were overweight, and 11.22% were obese. Most of the respondents had regular exercise habits (68.17%), had habitually stayed-up late (65.06%) and had been affected by persistent stress and/or recurrent anxiety/depressed mood (62.04%). A higher proportion of those with persistent stress and/or recurrent anxiety/depressed mood than those without habitually staying-up late (76.18%); consumed take-out food (54.92%), fried food (49.93%), snacks or desserts (50.51%); drank sugary drinks (46.57%); smoked (14.27%); and drank alcohol (23.34%). Gender (Female) (OR: 0.314, 95%CI: 0.292-0.336), age (OR: 1.742-2.334, 95%CI: 1.544-2.858), education (OR: 0.620-0.728, 95%CI: 0.445-0.973), living and working area (OR: 1.271, 95%CI: 1.192-1.355), breakfast (OR: 0.898, 95%CI: 0.839-0.960), fried food (OR: 1.133, 95%CI: 1.048-1.224), and alcohol consumption (OR: 1.111, 95%CI: 1.017-1.214) were factors for overweight/obesity. All of the aforementioned results were significant (P < 0.05). CONCLUSIONS: The overweight/obesity rate of Chinese HCWs is rather high, which might be directly associated with lifestyle behaviors. However, these behaviors fundamentally originated from persistent stress and/or recurrent anxiety/depression, mediated by lifestyle behaviors. Substantial measures should be taken for stress reduction and mental health promotion for overweight/obesity prevention and control among HCWs.


Asunto(s)
Sistema Hipotálamo-Hipofisario , Sobrepeso , Femenino , Humanos , Sobrepeso/epidemiología , Estudios Transversales , Sistema Hipófiso-Suprarrenal , Obesidad/epidemiología , Factores de Riesgo , Estilo de Vida
3.
J Am Chem Soc ; 144(30): 13903-13912, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35867482

RESUMEN

The isostructural heteroanionic compounds ß-LiAsS2-xSex (x = 0, 0.25, 1, 1.75, 2) show a positive correlation between selenium content and second-harmonic response and greatly outperform the industry standard AgGaSe2. These materials crystallize in the noncentrosymmetric space group Cc as one-dimensional 1/∞ [AsQ2]- (Q = S, Se, S/Se) chains consisting of corner-sharing AsQ3 trigonal pyramids with charge-balancing Li+ atoms interspersed between the chains. LiAsS2-xSex melts congruently for 0 ≤ x ≤ 1.75, but when the Se content exceeds x = 1.75, crystallization is complicated by a phase transition. This behavior is attributed to the ß- to α-phase transition present in LiAsSe2, which is observed in the Se-rich compositions. The band gap decreases with increasing Se content, starting at 1.63 eV (LiAsS2) and reaching 1.06 eV (ß-LiAsSe2). Second-harmonic generation measurements as a function of wavelength on powder samples of ß-LiAsS2-xSex show that these materials exhibit significantly higher nonlinearity than AgGaSe2 (d36 = 33 pm/V), reaching a maximum of 61.2 pm/V for LiAsS2. In comparison, single-crystal measurements for LiAsSSe yielded a deff = 410 pm/V. LiAsSSe, LiAsS0.25Se1.75, and ß-LiAsSe2 show phase-matching behavior for incident wavelengths exceeding 3 µm. The laser-induced damage thresholds from two-photon absorption processes are on the same order of magnitude as AgGaSe2, with S-rich materials slightly outperforming AgGaSe2 and Se-rich materials slightly underperforming AgGaSe2.

4.
J Nutr ; 152(5): 1283-1290, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-35349717

RESUMEN

BACKGROUND: Limited and inconclusive data exist concerning the associations between lipid-lowering drugs and serum micronutrient concentrations. METHODS: We conducted Mendelian randomization (MR) analyses to explore the associations between lipid-lowering drug targets and serum micronutrients. Single-nucleotide polymorphisms in genes encoding molecular targets of LDL cholesterol-lowering therapies were selected as instrumental variables for 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR; target of statins), proprotein convertase subtilisin/kexin type 9 (PCSK9; target of PCSK9 inhibitors), and Niemann-Pick C1-Like 1 (NPC1L1; target of ezetimibe). Exposure data were extracted from a published genome-wide association study (GWAS) of lipids in 188,577 European individuals, with outcome data obtained from the Integrative Epidemiology Unit (IEU) GWAS database (https://gwas.mrcieu.ac.uk). Overall, age and sex information were not calculable from the summary-level GWAS data. MR analyses were performed using the inverse-variance weighted method and MR sensitivity analysis methods. RESULTS: We found genetically proxied inhibition of HMGCR to lower iron (effect, -0.16; 95% CI: -0.27, -0.06; P value = 0.003), zinc (effect, -0.83; 95% CI: -1.36, -0.31; P value = 0.002), magnesium (effect, -0.17; 95% CI: -0.27, -0.06; P value = 0.003), potassium (effect, -0.17; 95% CI: -0.27, -0.06; P value = 0.002), genetically proxied inhibition of NPC1L1 to increase calcium (effect, 0.28; 95% CI: 0.10, 0.46; P value = 0.003), retinol (effect, 0.25; 95% CI: 0.07, 0.44; P value = 0.01), and genetically proxied inhibition of PCSK9 to increase vitamin D (effect, 0.10; 95% CI: 0.07, 0.12; P value = 1.8 × 10-19). These associations were robust in MR sensitivity analyses. However, the associations between genetically proxied inhibition of HMGCR and NPC1L1 and the micronutrients were not consistent in multiple comparisons. CONCLUSIONS: Our results provide evidence that statin use may lower serum concentrations of iron, zinc, magnesium, and potassium, PCSK9 inhibitors may increase serum vitamin D, and ezetimibe may increase serum calcium and retinol concentrations.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Proproteína Convertasa 9 , Calcio , LDL-Colesterol , Ezetimiba , Estudio de Asociación del Genoma Completo , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipolipemiantes , Hierro , Magnesio , Análisis de la Aleatorización Mendeliana , Micronutrientes , Inhibidores de PCSK9 , Potasio , Proproteína Convertasa 9/genética , Vitamina A , Vitamina D , Zinc
6.
Mol Genet Genomics ; 293(1): 225-235, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29038864

RESUMEN

Genome-wide association studies (GWAS) have been shown to have the potential of explaining more of the "missing heritability" of complex human phenotypes by improving statistical approaches. Here, we applied a genetic-pleiotropy-informed conditional false discovery rate (cFDR) to capture additional polygenic effects associated with estimated glomerular filtration rate (creatinine) (eGFRcrea) and type 2 diabetes (T2D). The cFDR analysis improves the identification of pleiotropic variants by incorporating potentially shared genetic mechanisms between two related traits. The Q-Q and fold-enrichment plots were used to assess the enrichment of SNPs associated with eGFRcrea or T2D, and Manhattan plots were used for showing chromosomal locations of the significant loci detected. By applying the cFDR method, we newly identified 74 loci for eGFRcrea and 3 loci for T2D with the cFDR criterion of 0.05 compared with previous related GWAS studies. Four shared SNPs were detected to be associated with both eGFRcrea and T2D at the significant conjunction cFDR level of 0.05, and these shared SNPs had not been reported in previous studies. In addition, we used DAVID analysis to perform functional analysis of the shared SNPs' annotated genes and found their potential hidden associations with eGFRcrea and T2D. In this study, the cFDR method shows the feasibility to detect more genetic variants underlying the heritability of eGFRcrea and T2D, and the overlapping SNPs identified could be regarded as candidate loci that provide a thread of genetic mechanisms between eGFRcrea and T2D in future research.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Predisposición Genética a la Enfermedad , Tasa de Filtración Glomerular/genética , Diabetes Mellitus Tipo 2/patología , Estudio de Asociación del Genoma Completo , Humanos , Herencia Multifactorial/genética , Fenotipo , Polimorfismo de Nucleótido Simple
7.
J Clin Lab Anal ; 32(6): e22430, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29516551

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignant tumor that severely threatens human health. To date, early detection for HCC patients is particularly significant due to their poor survival rates even after liver resection. METHODS: Therefore, an efficient and sensitive detection method for monitoring liver cancer, multiplex methylation-specific PCR (MSP) coupled with capillary electrophoresis, is developed. RESULTS: Simulations demonstrated that the methylation status of RASSF1A, p16, SFRP1, and ELF could be detected even when DNA equaled or exceeded 12.5 ng simultaneously. Also, its accuracy for methylation detection outweighed polyacrylamide gel electrophoresis (87.5%) and agarose electrophoresis (84.3%), reaching 92.1%. Subsequently, we implemented multiplex MSP with capillary electrophoresis to investigate methylation status of the four tumor suppressor genes in tissue specimens and explore the prognostic value for HCC patients. As the data suggested, multivariate cox regression analysis revealed that the recurrence-free survival of 46 patients was greatly associated with portal vein tumor thrombus (PVTT) and p16 methylation and receiver operating characteristic (ROC) curves demonstrated that the predictive range of portal vein tumor thrombus (PVTT) combined with p16 hypermethylation was more sensitive than that of either PVTT or p16 hypermethylation alone with regard to disease recurrence in patients with HCC, which could be testified as a valuable biomarker in Clinical application. CONCLUSION: Multiplex MSP coupled with capillary electrophoresis has an excellent prospect of clinical application for monitoring early liver cancer and screening valuable biomarkers for prognosis of HCC patients.

8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(1): 1-7, 2018 Jan.
Artículo en Zh | MEDLINE | ID: mdl-29737080

RESUMEN

OBJECTIVE: To study the regulation of suppressor of cytokine signaling 3 (SOCS3) expression bythe brother of the regulator of the imprinted site (BORIS) in hepatocellular carcinoma cell. METHODS: The expression of SOCS3 mRNA in HCC cell lines was detected by real-time quantitative PCR (qRT-PCR). The expression of SOCS3 protein in knockdown and overexpression BORIS of HCC cell lines was tested by Western blot. The SOCS3 gene promoter methylation statusin the knockdown and overexpression BORIS of hepatocarcinoma cell lines was detected by using methylation specific PCR (MSP-PCR) method.The potential BORIS binding site of SOCS3promoter region was found by UCSC database analysis.The enrichment of BORIS in SOCS3 promoter region in endogenous high expression BORIS of HCC cells was evaluated by using chromatin immunoprecipitation (ChIP)-qPCR (ChIP-qPCR).The SOCS3 promoter region histone methylation status in the knockdown and overexpression BORIS of HCC was detected by ChIP-qPCR. RESULTS: The expression of SOCS3 mRNA in hepatocellular carcinoma cells was higher and SOCS3 protein expression was down-regulated or up-regulated in the knockdown or overexpression of BORIS mRNA hepatocarcinoma cells,so BORIS has a positive regulatory effect on SOCS3 protein expression in hepatocarcinoma cells. MSP-PCR experiments showed that the SOCS3 promoter in SMMC-7721 and HepG2 cells was unmethylated and knockdown of BORIS did not change the methylation status; the SOCS3 promoter region of Huh7 cells was methylated; after overexpression of BORIS,the SOCS3 promoter region was changed to an unmethylated state; the SOCS3 promoter was unmethylated in HCCLM3,overexpression of BORIS did not alter the methylation status. The ChIP-qPCR assay demonstrated that BORIS specifically binds to the SOCS3 promoter region in HCC cells with high expression of BORIS. Histone methylation assay indicated that knockdown of BORIS reduced BORIS enrichment in the SOCS3 promoter region, with decreasing H3K4 me2 and increasing H3K27 me3 in the region of histone,whereas the overexpress BORIS in HCC cells showed the opposite situation. CONCLUSION: BORIS plays a role of epigenetic regulationon SOCS3 gene promoter methylation and histone methylation,modulating the expression of SOCS3,and then involved in the development of hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de Unión al ADN/metabolismo , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Metilación de ADN , Histonas/metabolismo , Humanos , Regiones Promotoras Genéticas
9.
J Mol Cell Cardiol ; 112: 1-7, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28843344

RESUMEN

Genome-wide association studies (GWAS) have been successfully applied in identifying single nucleotide polymorphisms (SNPs) associated with body mass index (BMI) and coronary heart disease (CAD). However, the SNPs to date can only explain a small percentage of the genetic variances of traits. Here, we applied a genetic pleiotropic conditional false discovery rate (cFDR) method that combines summary statistic p values from different multi-center GWAS datasets, to detect common genetic variants associated with these two traits. The enrichment of SNPs associated with BMI and CAD was assessed by conditional Q-Q plots and the common variants were identified by the cFDR method. By applying the cFDR level of 0.05, 7 variants were identified to be associated with CAD (2 variants being novel), 34 variants associated with BMI (11 variants being novel), and 3 variants associated with both BMI and CAD (2 variants being novel). The SNP rs653178 (ATXN2) is noteworthy as this variant was replicated in an independent analysis. SNP rs12411886 (CNNM2) and rs794356 (HIP1) were of note as the annotated genes may be associated with processes that are functionally important in lipid metabolism. In conclusion, the cFDR method identified novel variants associated with BMI and/or CAD by effectively incorporating different GWAS datasets.


Asunto(s)
Índice de Masa Corporal , Enfermedad de la Arteria Coronaria/genética , Pleiotropía Genética , Variación Genética , Estudio de Asociación del Genoma Completo , Humanos , Reproducibilidad de los Resultados
10.
J BUON ; 21(1): 142-51, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27061542

RESUMEN

PURPOSE: We conducted this meta-analysis of published case-control studies aiming to evaluate the relationship between abnormal suppression of cytokine signaling-1 (SOCS-1) promoter methylation and the risk of hepatocellular carcinoma (HCC). METHODS: Relevant studies were retrieved from PubMed, Embase, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI) and China Biological Medicine (CBM) databases without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. We calculated odds ratio (OR) and its 95 % confidence interval (95% CI) to estimate the correlations. RESULTS: Sixteen case-control studies with a total of 941 HCC patients and 114 individuals with benign liver diseases met our inclusion criteria. Our results demonstrated that the frequency of SOCS-1 promoter methylation in cancer tissues was significantly higher than in adjacent non-tumorous tissues and benign tissues (cancer tissue vs adjacent tissue: OR=3.05, 95%CI 1.62-5.77, p=0.001; cancer tissue vs benign tissue: OR=11.55, 95%CI 5.93-22.49, p=0.000). Subgroup analyses by ethnicity, detecting method and sample size also suggested that abnormal SOCS-1 promoter methylation was correlated to the risk of HCC in the majority of these subgroups. CONCLUSION: Our findings provide empirical evidence that abnormal SOCS-1 promoter methylation may contribute to the pathogenesis of HCC. Thus, detection of SOCS-1 promoter methylation may be a valuable diagnostic biomarker for HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Metilación de ADN , Neoplasias Hepáticas/genética , Regiones Promotoras Genéticas , Proteínas Supresoras de la Señalización de Citocinas/genética , Humanos , Sesgo de Publicación , Proteína 1 Supresora de la Señalización de Citocinas
11.
Int J Surg ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38896865

RESUMEN

INTRODUCTION: The postoperative recurrence of gastric cancer has a significant impact on the overall prognosis of patients. Therefore, accurately predicting the postoperative recurrence of gastric cancer is crucial. METHODS: This retrospective study gathered data from 2,813 gastric cancer patients who underwent radical surgery between 2011 and 2017 at two medical centers. Follow-up was extended until May 2023, and cases were categorized as recurrent or non-recurrent based on postoperative outcomes. Clinical pathological information and imaging data were collected for all patients. A new deep learning signature (DLS) was generated using pretreatment CT images, based on a pre-trained baseline (a customized Resnet50), for predicting postoperative recurrence. The deep learning fusion signature (DLFS) was created by combining the score of DLS with the weighted values of identified clinical features. The predictive performance of the model was evaluated based on discrimination, calibration, and clinical usefulness. Survival curves were plotted to investigate the differences between DLFS and prognosis. RESULTS: In this study, 2813 patients with gastric cancer (GC) were recruited and allocated into training, internal validation, and external validation cohorts. The DLFS was developed and assessed for its capability in predicting the risk of postoperative recurrence. The DLFS exhibited excellent performance with AUCs of 0.833 (95% CI, 0.809-0.858) in the training set, 0.831 (95% CI, 0.792-0.871) in the internal validation set, and 0.859 (95% CI, 0.806-0.912) in the external validation set, along with satisfactory calibration across all cohorts (P>0.05). Furthermore, the DLFS model significantly outperformed both the clinical model and DLS (P<0.05). High-risk recurrent patients exhibit a significantly poorer prognosis compared to low-risk recurrent patients (P<0.05). CONCLUSIONS: The integrated model developed in this study, focusing on GC patients undergoing radical surgery, accurately identifies cases at high risk of postoperative recurrence and highlights the potential of DLFS as a prognostic factor for GC patients.

12.
Chem Sci ; 12(43): 14557-14563, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34881007

RESUMEN

Natural systems produce various γ-dicarbonyl-bearing compounds that can covalently modify lysine in protein targets via the classic Paal-Knorr reaction. Among them is a unique class of lipid-derived electrophiles - isoketals that exhibit high chemical reactivity and critical biological functions. However, their target selectivity and profiles in complex proteomes remain unknown. Here we report a Paal-Knorr agent, 4-oxonon-8-ynal (herein termed ONAyne), for surveying the reactivity and selectivity of the γ-dicarbonyl warhead in biological systems. Using an unbiased open-search strategy, we demonstrated the lysine specificity of ONAyne on a proteome-wide scale and characterized six probe-derived modifications, including the initial pyrrole adduct and its oxidative products (i.e., lactam and hydroxylactam adducts), an enlactam adduct from dehydration of hydroxylactam, and two chemotypes formed in the presence of endogenous formaldehyde (i.e., fulvene and aldehyde adducts). Furthermore, combined with quantitative chemoproteomics in a competitive format, ONAyne permitted global, in situ, and site-specific profiling of targeted lysine residues of two specific isomers of isoketals, levuglandin (LG) D2 and E2. The functional analyses reveal that LG-derived adduction drives inhibition of malate dehydrogenase MDH2 and exhibits a crosstalk with two epigenetic marks on histone H2B in macrophages. Our approach should be broadly useful for target profiling of bioactive γ-dicarbonyls in diverse biological contexts.

13.
Antioxid Redox Signal ; 33(15): 1061-1076, 2020 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31411056

RESUMEN

Aims: Cysteine persulfidation (also called sulfhydration or sulfuration) has emerged as a potential redox mechanism to regulate protein functions and diverse biological processes in hydrogen sulfide (H2S) signaling. Due to its intrinsically unstable nature, working with this modification has proven to be challenging. Although methodological progress has expanded the inventory of persulfidated proteins, there is a continued need to develop methods that can directly and unequivocally identify persulfidated cysteine residues in complex proteomes. Results: A quantitative chemoproteomic method termed as low-pH quantitative thiol reactivity profiling (QTRP) was developed to enable direct site-specific mapping and reactivity profiling of proteomic persulfides and thiols in parallel. The method was first applied to cell lysates treated with NaHS, resulting in the identification of overall 1547 persulfidated sites on 994 proteins. Structural analysis uncovered unique consensus motifs that might define this distinct type of modification. Moreover, the method was extended to profile endogenous protein persulfides in cells expressing H2S-generating enzyme, mouse tissues, and human serum, which led to additional insights into mechanistic, structural, and functional features of persulfidation events, particularly on human serum albumin. Innovation and Conclusion: Low-pH QTRP represents the first method that enables direct and unbiased proteomic mapping of cysteine persulfidation. Our method allows to generate the most comprehensive inventory of persulfidated targets of NaHS so far and to perform the first analysis of in vivo persulfidation events, providing a valuable tool to dissect the biological functions of this important modification.


Asunto(s)
Cisteína/metabolismo , Procesamiento Proteico-Postraduccional , Proteómica/métodos , Sulfuros/metabolismo , Cisteína/química , Humanos , Sulfuro de Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Proteoma , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/metabolismo
14.
Nat Protoc ; 15(9): 2891-2919, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32690958

RESUMEN

Cysteine is unique among all protein-coding amino acids, owing to its intrinsically high nucleophilicity. The cysteinyl thiol group can be covalently modified by a broad range of redox mechanisms or by various electrophiles derived from exogenous or endogenous sources. Measuring the response of protein cysteines to redox perturbation or electrophiles is critical for understanding the underlying mechanisms involved. Activity-based protein profiling based on thiol-reactive probes has been the method of choice for such analyses. We therefore adapted this approach and developed a new chemoproteomic platform, termed 'QTRP' (quantitative thiol reactivity profiling), that relies on the ability of a commercially available thiol-reactive probe IPM (2-iodo-N-(prop-2-yn-1-yl)acetamide) to covalently label, enrich and quantify the reactive cysteinome in cells and tissues. Here, we provide a detailed and updated workflow of QTRP that includes procedures for (i) labeling of the reactive cysteinome from cell or tissue samples (e.g., control versus treatment) with IPM, (ii) processing the protein samples into tryptic peptides and tagging the probe-modified peptides with isotopically labeled azido-biotin reagents containing a photo-cleavable linker via click chemistry reaction, (iii) capturing biotin-conjugated peptides with streptavidin beads, (iv) identifying and quantifying the photo-released peptides by mass spectrometry (MS)-based shotgun proteomics and (v) interpreting MS data by a streamlined informatic pipeline using a proteomics software, pFind 3, and an automatic post-processing algorithm. We also exemplified here how to use QTRP for mining H2O2-sensitive cysteines and for determining the intrinsic reactivity of cysteines in a complex proteome. We anticipate that this protocol should find broad applications in redox biology, chemical biology and the pharmaceutical industry. The protocol for sample preparation takes 3 d, whereas MS measurements and data analyses require 75 min and <30 min, respectively, per sample.


Asunto(s)
Cisteína/metabolismo , Proteómica/métodos , Células HEK293 , Humanos , Oxidación-Reducción
15.
Int J Biochem Cell Biol ; 120: 105685, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31917284

RESUMEN

The epigenetic silencing mechanism of suppressor 3 of cytokine signaling (SOCS3) in cancers has not been fully elucidated. Polycomb repressive complexes 2 (PRC2), an important epigenetic regulatory factors, exerts a critical role in repressing the initial phase of gene transcription. Whether PRC2 participates the down- regulation of SOCS3 in Hepatocellular carcinoma (HCC) remains unclear and how does PRC2 be recruited target gene still needs to explore. In this study, Using TCGA HCC dataset, and detecting HCC tissue specimens and cell lines, we found that SOCS3 expression in HCC was inversely related to that of EZH2, and depended on its promoter methylation status. CTCF, vigilin, EZH2 and H3K27me3 were enriched at CTCF and EZH2 binding sites on the methylated SOCS3 gene promoter. The depletion of CTCF did not affect expression of EZH2 and DNMT1, but decrease recruitment of CTCF, vigilin, EZH2 and H3K27me3. Further, knockdown of CTCF led to a loss of methylation of the methylated SOCS3 promoter, which sequentially increased the expression of SOCS3 and decreased the expression of pSTAT3, the downstream effector. These findings suggest that the CTCF dependent recruitment of EZH2 to the SOCS3 gene promoter is likely to participate in the epigenetic silencing of SOCS3 and in regulating its gene expression.


Asunto(s)
Factor de Unión a CCCTC/metabolismo , Carcinoma Hepatocelular/metabolismo , Metilación de ADN , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Neoplasias Hepáticas/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/biosíntesis , Factor de Unión a CCCTC/biosíntesis , Factor de Unión a CCCTC/deficiencia , Factor de Unión a CCCTC/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proteína Potenciadora del Homólogo Zeste 2/biosíntesis , Proteína Potenciadora del Homólogo Zeste 2/genética , Epigénesis Genética , Técnicas de Silenciamiento del Gen , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Regiones Promotoras Genéticas , Proteína 3 Supresora de la Señalización de Citocinas/genética , Transfección
16.
Clin Exp Med ; 18(1): 79-87, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28951980

RESUMEN

SOCS3 as an important negative regulator of IL6/JAK/STAT3 signaling pathway may be early critical determinants of carcinogenesis. This study aimed to explore the aberrant promoter methylation of SOCS3 gene in circulating DNA as a noninvasive biomarker for screening hepatocellular carcinoma (HCC) high-risk individuals and for prognosis of HCC patients after partial hepatectomy. We detected its methylation status in 116 liver tissues and 326 plasma specimens of different hepatic diseases and healthy subjects, and its mRNA and protein expression in tissues. Higher methylation rate was remarkably detected in HCC (47.92%), compared with corresponding non-tumor (25.0%), liver cirrhosis (LC) (10.0%), benign liver diseases (0%) and normal liver tissues (0%) (all P < 0.05). SOCS3 mRNA level was significantly lower in methylated HCC tissues (P < 0.05). The expressions of SOCS3 and pSTAT3 were affected by methylation status. Correlation and consistency of SOCS3 methylation were found between cancer tissue and corresponding plasma (P < 0.001, κ = 0.747). The detection rate of plasma for HCC reached 73.91%, with no false positive error. SOCS3 methylation status both in tissue and plasma was significantly associated with AFP400, tumor size, tumor differentiation, LC, metastasis and recurrence (all P < 0.05). Patients with SOCS3 methylation were followed up a markedly poorer prognosis than those unmethylated for disease-free survival (P < 0.05). These data indicate that methylation status of SOCS3 in plasma cell-free DNA can correctly reflect that in tissue DNA and be used as a noninvasive potential biomarker for chronic liver disease monitoring, predicting the degree of malignancy and poor prognosis of HCC.


Asunto(s)
Carcinoma Hepatocelular/patología , Metilación de ADN , ADN/análisis , Neoplasias Hepáticas/patología , Hígado/patología , Plasma/química , Proteína 3 Supresora de la Señalización de Citocinas/genética , Adulto , Anciano , Pueblo Asiatico , Biomarcadores/sangre , Carcinoma Hepatocelular/diagnóstico , ADN/química , Femenino , Estudios de Seguimiento , Perfilación de la Expresión Génica , Humanos , Neoplasias Hepáticas/diagnóstico , Masculino , Persona de Mediana Edad , Pronóstico , Regiones Promotoras Genéticas , ARN Mensajero/análisis
17.
J Diabetes Complications ; 32(12): 1105-1112, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30270018

RESUMEN

Genome-wide association studies (GWASs) have been performed extensively in diverse populations to identify single nucleotide polymorphisms (SNPs) associated with complex diseases or traits. However, to date, the SNPs identified fail to explain a large proportion of the variance of the traits/diseases. GWASs on type 2 diabetes (T2D) and coronary artery disease (CARD) are generally performed as single-trait studies, rather than analyzing the related traits simultaneously. Despite the extensive evidence suggesting that these two phenotypes share both genetic and environmental risk factors, the shared overlapping genetic biological mechanisms between these traits remain largely unexplored. Here, we adopted a recently developed genetic pleiotropic conditional false discovery rate (cFDR) approach to discover novel loci associated with T2D and CARD by incorporating the summary statistics from existing GWASs of these two traits. Applying the cFDR level of 0.05, 33 loci were identified for T2D and 34 loci for CARD, 9 of which for both. By incorporating pleiotropic effects into a conditional analysis framework, we observed that there is significant pleiotropic enrichment between T2D and CARD. These findings may provide novel insights into the etiology of T2D and CARD, as well as the processes that may influence disease development both individually and jointly.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Diabetes Mellitus Tipo 2/genética , Pleiotropía Genética , Estudio de Asociación del Genoma Completo/métodos , Polimorfismo de Nucleótido Simple , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/epidemiología , Interpretación Estadística de Datos , Conjuntos de Datos como Asunto , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/genética , Epistasis Genética , Reacciones Falso Positivas , Redes Reguladoras de Genes/fisiología , Sitios Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/normas , Estudio de Asociación del Genoma Completo/estadística & datos numéricos , Humanos , Mapas de Interacción de Proteínas/genética
18.
J Cancer ; 9(12): 2203-2210, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29937940

RESUMEN

Background: Most hepatocellular carcinoma (HCC) patients have undergone a progression from chronic hepatitis, then liver cirrhosis (LC), and finally to carcinoma. The objective of this study was to elucidate risk factors to predict HCC development for cirrhosis patients. Methods: Multiple methylated specific PCR (MSP) was applied to determine methylation status of heparocarcinogenesis-related genes in 396 tissue and plasma specimens and multivariate cox model was used to analyze the relationship between risk variables and HCC development among cirrhosis patients, followed up in a median period of 30 months. Results: Among 105 LC cases, HCC incidence rate at 30 months was 30.48% (32/105), which were statistically associated with patients' age and aberrant methylation of p16, SFRP, and LINE1 (p<0.05). Receiver operating characteristic (ROC) curve showed the overall predictive accuracy reached the highest (90.7%) if the four risk variables were concurrent to predict HCC development. Moreover, along with the growth of age from 0-40, 40-55, to 55-70 years or the increased number of aberrantly-methylated gene from 0-1 to 2-3, the HCC incidence rate of cirrhosis patients rised from 10.00%, 12.28% to 82.14% and 17.44% to 89.47%, separately. Thus, based on combined analysis with diverse age and number of aberrantly-methylated gene, 105 cases were divided into five groups and computed their respective HCC incidecne rate to categorize them into different risk groups. Of note, A significant lifting of HCC incidence rate in the high-risk group (40-55 years coupled with 2-3 aberrantly-methylated genes, 55-70 years coupled with 0-1 aberrantly-methylated gene, 55-70 years coupled with 2-3 aberrantly-methylated genes; n=33) was observed compared with the low-risk group (0-40 years coupled with 0-1 aberrantly-methylated gene, 40-55 years coupled with 0-1 aberrantly-methylated gene; (n=72) (p<0.01). Conclusions: Ultimately, high-risk cirrhosis patients with 55-over years or 2-3 aberrantly-methylated genes should be paid more attention to be regularly screened with HCC development.

19.
Gene ; 629: 29-34, 2017 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-28764977

RESUMEN

The brother of the regulator of the imprinted site (BORIS), an 11 zinc finger (ZF) protein, is a paralogue of CCCTC-binding factor (CTCF), involves in a few crucial events of chromatin functions, complex transcription regulation during spermatogenesis. As a novel tumor oncogene, abnormal expression of BORIS is observed in human hepatocellular carcinoma, however, the underlying mechanisms remain largely unexplored. In this study, the methylation status of BORIS was tested by methylation specific polymerase chain reaction (MSP) in human HCC cell lines and 43 pairs of tissue specimens. Frequently demethylation of BORIS in HCC was significantly higher than that in the paired adjacent non-tumor tissues (P=0.019), and it was correlated with tumor size (P=0.025) and clinical TNM stage (P=0.035). Patients with hypomethylated BORIS had a shorter disease free survival than those without demethylated BORIS (P=0.006). Further, analyses using Cox regression have indicated that the BORIS demethylation status was an independent risk to the reduced overall survival rate of HCC patients (P=0.035). These findings provide clues to clarify whether the demethylation may lead to activation of the promoter for upregulation expression of BORIS. In conclusions, aberrant BORIS hypomethylation is a promising biomarker for the prognosis of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Metilación de ADN , Proteínas de Unión al ADN/genética , Neoplasias Hepáticas/genética , Regiones Promotoras Genéticas , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Femenino , Humanos , Hígado/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Pronóstico
20.
Medicine (Baltimore) ; 96(12): e6420, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28328845

RESUMEN

Brother of regulator of imprinted sites (BORIS) is a DNA-binding protein that is normally expressed in the testes. However, aberrant expression of BORIS is observed in various carcinomas, indicating a malignant role for this protein. Furthermore, abolishment or reduction of suppressor of cytokine signaling 3 (SOCS3) expression directed by promoter methylation is considered significant in hepatocellular carcinoma (HCC) carcinogenesis. This study aims to investigate BORIS and SOCS3 expression in HCC specimens and assess the prognostic significance of these proteins.BORIS and SOCS3 expression was examined using immunohistochemistry in HCC tissues, along with corresponding paracarcinomatous, cirrhosis, hepatitis, and normal liver tissues. The expression levels of these 2 proteins in HCC were evaluated for their association with clinicopathological parameters. Survival analysis was performed using Kaplan-Meier curves, the log-rank test, and multivariate Cox regression analysis.BORIS expression was significantly higher in HCC tissues than in normal liver tissues. In contrast, SOCS3 expression was dramatically lower in HCC tissues. BORIS expression was associated with tumor size, differentiation grade, satellite lesions, and recurrence while SOCS3 expression correlated with differentiation grade, vascular invasion, and recurrence. A significant negative correlation between BORIS and SOCS3 was observed. Patients with high BORIS expression and/or low SOCS3 expression had poorer postoperative survival. Patients with both these characteristics had the poorest prognostic outcome.BORIS and SOCS3 are promising as valuable indicators for predicting HCC prognosis.


Asunto(s)
Carcinoma Hepatocelular/patología , Proteínas de Unión al ADN/biosíntesis , Neoplasias Hepáticas/patología , Proteínas Supresoras de la Señalización de Citocinas/biosíntesis , Biomarcadores de Tumor , Femenino , Humanos , Estimación de Kaplan-Meier , Hígado/fisiopatología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Pronóstico , Carga Tumoral
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