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1.
Cell ; 155(5): 1034-48, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24267889

RESUMO

LINE-1s are active human DNA parasites that are agents of genome dynamics in evolution and disease. These streamlined elements require host factors to complete their life cycles, whereas hosts have developed mechanisms to combat retrotransposition's mutagenic effects. As such, endogenous L1 expression levels are extremely low, creating a roadblock for detailed interactomic analyses. Here, we describe a system to express and purify highly active L1 RNP complexes from human suspension cell culture and characterize the copurified proteome, identifying 37 high-confidence candidate interactors. These data sets include known interactors PABPC1 and MOV10 and, with in-cell imaging studies, suggest existence of at least three types of compositionally and functionally distinct L1 RNPs. Among the findings, UPF1, a key nonsense-mediated decay factor, and PCNA, the polymerase-delta-associated sliding DNA clamp, were identified and validated. PCNA interacts with ORF2p via a PIP box motif; mechanistic studies suggest that this occurs during or immediately after target-primed reverse transcription.


Assuntos
Elementos Nucleotídeos Longos e Dispersos , Proteoma/análise , Ribonucleoproteínas/análise , Sequência de Aminoácidos , Animais , Regulação para Baixo , Genoma Humano , Humanos , Espectrometria de Massas , Dados de Sequência Molecular , Fases de Leitura Aberta , Antígeno Nuclear de Célula em Proliferação/química , Antígeno Nuclear de Célula em Proliferação/isolamento & purificação , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Helicases , Ribonucleoproteínas/isolamento & purificação , Alinhamento de Sequência , Transativadores/química , Transativadores/isolamento & purificação , Transativadores/metabolismo
2.
Hum Mol Genet ; 32(16): 2646-2655, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37369012

RESUMO

Animal studies implicate one-carbon metabolism and DNA methylation genes in hepatocellular carcinoma (HCC) development in the setting of metabolic perturbations. Using human samples, we investigated the associations between common and rare variants in these closely related biochemical pathways and risk for metabolic HCC development in a multicenter international study. We performed targeted exome sequencing of 64 genes among 556 metabolic HCC cases and 643 cancer-free controls with metabolic conditions. Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for multiple comparisons. Gene-burden tests were used for rare variant associations. Analyses were performed in the overall sample and among non-Hispanic whites. The results show that among non-Hispanic whites, presence of rare functional variants in ABCC2 was associated with 7-fold higher risk of metabolic HCC (OR = 6.92, 95% CI: 2.38-20.15, P = 0.0004), and this association remained significant when analyses were restricted to functional rare variants observed in ≥2 participants (cases 3.2% versus controls 0.0%, P = 1.02 × 10-5). In the overall multiethnic sample, presence of rare functional variants in ABCC2 was nominally associated with metabolic HCC (OR = 3.60, 95% CI: 1.52-8.58, P = 0.004), with similar nominal association when analyses were restricted to functional rare variants observed in ≥2 participants (cases 2.9% versus controls 0.2%, P = 0.006). A common variant in PNPLA3 (rs738409[G]) was associated with higher HCC risk in the overall sample (P = 6.36 × 10-6) and in non-Hispanic whites (P = 0.0002). Our findings indicate that rare functional variants in ABCC2 are associated with susceptibility to metabolic HCC in non-Hispanic whites. PNPLA3-rs738409 is also associated with metabolic HCC risk.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Metilação de DNA/genética , Predisposição Genética para Doença , Estudos de Casos e Controles , Células Germinativas/patologia , Carbono , Polimorfismo de Nucleotídeo Único/genética
3.
Hepatology ; 80(1): 87-101, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38381705

RESUMO

BACKGROUND AND AIMS: Despite the substantial impact of environmental factors, individuals with a family history of liver cancer have an increased risk for HCC. However, genetic factors have not been studied systematically by genome-wide approaches in large numbers of individuals from European descent populations (EDP). APPROACH AND RESULTS: We conducted a 2-stage genome-wide association study (GWAS) on HCC not affected by HBV infections. A total of 1872 HCC cases and 2907 controls were included in the discovery stage, and 1200 HCC cases and 1832 controls in the validation. We analyzed the discovery and validation samples separately and then conducted a meta-analysis. All analyses were conducted in the presence and absence of HCV. The liability-scale heritability was 24.4% for overall HCC. Five regions with significant ORs (95% CI) were identified for nonviral HCC: 3p22.1, MOBP , rs9842969, (0.51, [0.40-0.65]); 5p15.33, TERT , rs2242652, (0.70, (0.62-0.79]); 19q13.11, TM6SF2 , rs58542926, (1.49, [1.29-1.72]); 19p13.11 MAU2 , rs58489806, (1.53, (1.33-1.75]); and 22q13.31, PNPLA3 , rs738409, (1.66, [1.51-1.83]). One region was identified for HCV-induced HCC: 6p21.31, human leukocyte antigen DQ beta 1, rs9275224, (0.79, [0.74-0.84]). A combination of homozygous variants of PNPLA3 and TERT showing a 6.5-fold higher risk for nonviral-related HCC compared to individuals lacking these genotypes. This observation suggests that gene-gene interactions may identify individuals at elevated risk for developing HCC. CONCLUSIONS: Our GWAS highlights novel genetic susceptibility of nonviral HCC among European descent populations from North America with substantial heritability. Selected genetic influences were observed for HCV-positive HCC. Our findings indicate the importance of genetic susceptibility to HCC development.


Assuntos
Carcinoma Hepatocelular , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/genética , Masculino , Feminino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Estudos de Casos e Controles , Polimorfismo de Nucleotídeo Único , Idoso , Loci Gênicos , População Branca/genética
4.
Am J Hum Genet ; 108(10): 1852-1865, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34559995

RESUMO

Genome-wide association studies (GWASs) have discovered 20 risk loci in the human genome where germline variants associate with risk of pancreatic ductal adenocarcinoma (PDAC) in populations of European ancestry. Here, we fine-mapped one such locus on chr16q23.1 (rs72802365, p = 2.51 × 10-17, OR = 1.36, 95% CI = 1.31-1.40) and identified colocalization (PP = 0.87) with aberrant exon 5-7 CTRB2 splicing in pancreatic tissues (pGTEx = 1.40 × 10-69, ßGTEx = 1.99; pLTG = 1.02 × 10-30, ßLTG = 1.99). Imputation of a 584 bp structural variant overlapping exon 6 of CTRB2 into the GWAS datasets resulted in a highly significant association with pancreatic cancer risk (p = 2.83 × 10-16, OR = 1.36, 95% CI = 1.31-1.42), indicating that it may underlie this signal. Exon skipping attributable to the deletion (risk) allele introduces a premature stop codon in exon 7 of CTRB2, yielding a truncated chymotrypsinogen B2 protein that lacks chymotrypsin activity, is poorly secreted, and accumulates intracellularly in the endoplasmic reticulum (ER). We propose that intracellular accumulation of a nonfunctional chymotrypsinogen B2 protein leads to ER stress and pancreatic inflammation, which may explain the increased pancreatic cancer risk in carriers of CTRB2 exon 6 deletion alleles.


Assuntos
Quimotripsina/genética , Neoplasias Pancreáticas/patologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Deleção de Sequência , Estudos de Casos e Controles , Quimotripsina/antagonistas & inibidores , Quimotripsina/metabolismo , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/metabolismo
5.
Diabetes Obes Metab ; 26(6): 2176-2187, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38419419

RESUMO

AIMS: To assess the excess risk of cardiovascular disease (CVD) associated with different criteria for metabolic health, and the interplay of body size, insulin sensitivity and metabolic health with CVD risk. MATERIALS AND METHODS: We conducted a prospective study involving 115 638 participants from the China Cardiometabolic Disease and Cancer Cohort (4C) Study. Metabolic health was defined using three different definitions: (1) insulin sensitivity defined by homeostatic model assessment of insulin resistance index; (2) absence of metabolic syndrome according to the National Cholesterol Education Program Adult Treatment Panel III criteria; and (3) simultaneous absence of metabolic abnormalities (diabetes, hypertension, dyslipidaemia). The primary endpoint was a composite of incident CVD events comprising the first occurrence of myocardial infarction, stroke, heart failure, or cardiovascular death. RESULTS: During a mean 3.61-year follow-up period, obese individuals with insulin sensitivity (multivariable-adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.37-2.08), or without metabolic syndrome (HR 1.46, 95% CI 1.13-1.89) still exhibited increased CVD risks, when compared to their normal-weight counterparts. Otherwise, those with obesity but simultaneous absence of metabolic abnormalities demonstrated similar CVD risk compared to normal-weight individuals (HR 0.91, 95% CI 0.53-1.59). CVD risk increased with the number of abnormalities across body mass index categories, regardless of insulin sensitivity. CONCLUSIONS: This study emphasizes the need for refined definitions of metabolic health and advocates for meticulous screening for metabolic abnormalities to reduce cardiovascular risks, even in individuals with normal weight and insulin sensitivity.


Assuntos
Tamanho Corporal , Doenças Cardiovasculares , Resistência à Insulina , Síndrome Metabólica , Obesidade , Humanos , Masculino , Feminino , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , China/epidemiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/complicações , Obesidade/complicações , Obesidade/epidemiologia , Fatores de Risco , Idoso , Neoplasias/epidemiologia , Estudos de Coortes , Seguimentos , População do Leste Asiático
6.
Phys Chem Chem Phys ; 26(23): 16871-16882, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38832822

RESUMO

There is still a paucity of fundamental understanding about the reaction of ammonia decomposition over TiO2, especially the role of water. Herein, FPMD and DFT calculations were used to address this concern. The results reveal that ammonia decomposition in pure ammonia causes the hydroxylation of the surfaces and reduction of the proton acceptor sites, making proton transfer (PT) difficult, increasing the distances between the NH3 and Obr sites and changing the adsorption configurations of NH3, which are not favourable for accepting protons from NH3 dissociation. When water is introduced, the local hydrogen bonding environment, consisting of NH3 and H2O with the H2O dynamically close to the ObrH, promotes the increase of the positive charge of H atoms from 0.133 to 1.47 e, which increases the ObrH bond dipole moment from 1.136 to 1.400 Debye, resulting in the shortening of the H-bond distances between NH3 and ObrH (1.858 vs. 1.945 Å of only NH3) and enlarging the ObrH bonds (0.980 vs. 1.120 Å). This reduces the activation energy barriers of ObrH deprotonation and causes the surfaces to have low hydroxyl coverage from 0.425 to 0.382 eV. Our study reveals the role of water and provides new insights into ammonia decomposition on TiO2.

7.
J Environ Manage ; 353: 120116, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280251

RESUMO

Nutrient removal from sewage is transitioning to nutrient recovery. However, biological treatment technologies to remove and recover nutrients from domestic sewage are still under investigation. This study delved into the integration of ammonium assimilation with denitrifying phosphorus removal (DPR) as a method for efficient nutrient management in sewage treatment. Results indicated this approach eliminated over 80 % of the nitrogen in the influent, simultaneously recovering over 60 % of the nitrogen as the activated sludge through ammonia assimilation, and glycerol facilitated this process. The nitrification/denitrifying phosphorus removal ensured the stability of both nitrogen and phosphorus removal. The phosphorus removal rate exceeded 96 %, and the DPR rate reached over 90 %. Network analysis highlighted a stable community structure with Proteobacteria and Bacteroidota driving ammonium assimilation. The synergistic effect of fermentation bacteria, denitrifying glycogen-accumulating organisms, and denitrifying phosphorus-accumulating organisms contributed to the stability of nitrogen and phosphorus removal. This approach offers a promising method for sustainable nutrient management in sewage treatment.


Assuntos
Compostos de Amônio , Purificação da Água , Esgotos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Desnitrificação , Fósforo , Reatores Biológicos , Nitrificação , Nutrientes , Nitrogênio
8.
Microb Pathog ; 182: 106248, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37423493

RESUMO

Salmonella enterica serovar Derby (S. Derby) is one of the most common Salmonella serovars which can infect poultry, swine, and humans. With the reduction of the sequencing cost and the improvement of sequencing technology, whole genome sequencing (WGS) has become an important method for bacterial determination, molecular investigation, and pathogenic tracing analysis. In this study, we investigated S. Derby isolates from different sources in China using in-silico multilocus sequence typing (MLST), core genome MLST (cgMLST) and whole genome MLST (wgMLST) analysis based on WGS. The results showed that 21 S. Derby strains were divided into 3 STs using MLST analysis, including ST40 (n = 19, accounting for 90.48%), ST71 (n = 1, accounting for 4.76%) and ST8016 (n = 1, accounting for 4.76%). cgMLST and wgMLST analysis categorized the tested strains into 13 cgSTs and 21 wgSTs, respectively. The minimum spanning trees of cgMLST and wgMLST both divided these strains into 3 clusters and 4 singletons. In addition, virulence gene profiles of S. Derby isolates were also analyzed, and a total of 174 virulence genes belonged to 8 categories were identified. In summary, we studied genomic typing, phylogenetic relationship and virulence gene profiles of S. Derby strains from different sources in China. These findings were beneficial for the epidemiology and pathogenesis of Salmonella.


Assuntos
Genoma Bacteriano , Salmonella , Humanos , Animais , Suínos , Virulência/genética , Tipagem de Sequências Multilocus/métodos , Filogenia , Genoma Bacteriano/genética , Genômica
9.
Microb Pathog ; 182: 106275, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37516211

RESUMO

Salmonella is an important zoonotic and foodborne pathogen that can infect humans and animals, causing severe concerns about food safety and a heavy financial burden worldwide. The pathogen can adhere to living and abiotic surfaces by forming biofilms, which increases the risk of transmission and infection. In this study, we investigated the biofilm-forming ability of 243 Salmonella strains of 36 serotypes from different sources in China using microplate crystal violet staining method. The results showed that 99.6% tested strains, with the exception of one strain of S. Thompson, were capable of forming biofilms. The strains with the biofilm-forming ability of strong, medium and weak accounted for 2.88%, 24.28% and 72.43%, respectively. The strains of S. Havana and S. Hvittingfoss had the strongest biofilm-forming ability, with the OD570 of 0.81 ± 0.02 and 0.81 ± 0.38, respectively, while the strains of S. Agona and S. Bovismorbificans had the weakest biofilm-forming ability, with the OD570 of 0.16 ± 0.02 and 0.15 ± 0.00, respectively. Furthermore, statistical analysis results demonstrated that isolation of source had no effect on the biofilm formation ability, while the detection rates of pefABCD and ddhC were positively correlated with the biofilm formation ability of Salmonella. In particular, the detection rate of ddhC gene was more than 60% in the biofilm forming strains. These findings have important guiding significance for the investigation of pathogenesis, as well as the prevention and control of salmonellosis.


Assuntos
Salmonella enterica , Humanos , Animais , Salmonella enterica/genética , Sorogrupo , Biofilmes , Salmonella , China
10.
BMC Cancer ; 23(1): 103, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717797

RESUMO

BACKGROUND: Real-world data of Palbociclib are insufficient in China. This study aimed to investigate the treatment pattern and real-world outcomes in hormone receptor positive and human epidermal growth factor 2 receptor negative (HR+/HER2-) metastatic breast cancer (MBC) patients treated with Palbociclib in the northwest of China. METHODS: HR+/HER2- MBC patients who received Palbociclib in 8 centers from July 2017 to September 2019 were retrospectively included in this study. Real-world objective response rate (ORR), progression-free survival (PFS) and safety profiles were analyzed. The survival curves were plotted by the Kaplan-Meier method to analyze PFS, which was verified by the log-rank test. RESULTS: In total, 211 women were eligible for the analysis. A total of 85 patients (40.3%), 78 (37.0%), and 48 (22.7%) received Palbociclib in the first-, second-, third- or later-line setting, respectively. 46 patients achieved partial response and 145 patients experienced stable disease, with an ORR of 21.8% and a disease control rate of 90.5%. Following a median follow-up period of 14.2 months, the median PFS was 12.2 months (95% confidence interval, 10.1-14.3 m), and the median overall survival was not reached. Early Palbociclib initiation, sensitivity or acquired resistance to endocrine therapy, estrogen receptor and progesterone receptor double positivity, less than 3 metastatic sites, without visceral metastasis, bone metastasis only, without prior chemotherapy or endocrine therapy were associated with a prolonged PFS in MBC (All P < 0.05). The most common grade 3 or 4 adverse events (AE) was neutropenia (36.5%), and the most common nonhematologic AE was fatigue (10.9%). No patient experienced AE leading to treatment discontinuation. CONCLUSION: Palbociclib plus endocrine therapy exhibited favorable effectiveness and manageable toxicities in the real-world setting, supporting their use in Chinese patients with HR+/HER2 - MBC.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Receptor ErbB-2/metabolismo , Estudos Retrospectivos
11.
Gastric Cancer ; 26(6): 904-917, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37572185

RESUMO

BACKGROUND: Peroxisome proliferator-activated receptor delta (PPARδ) promotes inflammation and carcinogenesis in many organs, but the underlying mechanisms remains elusive. In stomachs, PPARδ significantly increases chemokine Ccl20 expression in gastric epithelial cells while inducing gastric adenocarcinoma (GAC). CCR6 is the sole receptor of CCL20. Here, we examine the role of PPARδ-mediated Ccl20/Ccr6 signaling in GAC carcinogenesis and investigate the underlying mechanisms. METHODS: The effects of PPARδ inhibition by its specific antagonist GSK3787 on GAC were examined in the mice with villin-promoter-driven PPARδ overexpression (PpardTG). RNAscope Duplex Assays were used to measure Ccl20 and Ccr6 levels in stomachs and spleens. Subsets of stomach-infiltrating immune cells were measured via flow cytometry or immunostaining in PpardTG mice fed GSK3787 or control diet. A panel of 13 optimized proinflammatory chemokines in mouse sera were quantified by an enzyme-linked immunosorbent assay. RESULTS: GSK3787 significantly suppressed GAC carcinogenesis in PpardTG mice. PPARδ increased Ccl20 level to chemoattract Ccr6+ immunosuppressive cells, including tumor-associated macrophages, myeloid-derived suppressor cells and T regulatory cells, but decreased CD8+ T cells in gastric tissues. GSK3787 suppressed PPARδ-induced gastric immunosuppression by inhibiting Ccl20/Ccr6 axis. Furthermore, Ccl20 protein levels increased in sera of PpardTG mice starting at the age preceding gastric tumor development and further increased with GAC progression as the mice aged. GSK3787 decreased the PPARδ-upregulated Ccl20 levels in sera of the mice. CONCLUSIONS: PPARδ dysregulation of Ccl20/Ccr6 axis promotes GAC carcinogenesis by remodeling gastric tumor microenvironment. CCL20 might be a potential biomarker for the early detection and progression of GAC.


Assuntos
Adenocarcinoma , PPAR delta , Neoplasias Gástricas , Humanos , Animais , Camundongos , Quimiocina CCL20/genética , Quimiocina CCL20/metabolismo , PPAR delta/genética , Linfócitos T CD8-Positivos , Microambiente Tumoral , Carcinogênese , Receptores CCR6/genética , Receptores CCR6/metabolismo
12.
Antonie Van Leeuwenhoek ; 116(6): 565-576, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37186068

RESUMO

Cryptococcal species often cause lung infections and are the main cause of fungal meningitis. Claudin-4 appears to be a major structural component that maintains a tight alveolar barrier and prevents fluid and electrolyte leakage into the alveolar space. We aimed to determine whether S7-tetrahydrocurcumin (THC) could clearance of C. deneoformans and regulate claudin-4 expression during C. deneoformans infection. We investigated the effect of THC on C. deneoformans infection and its possible mechanism in vivo. Transmission electron microscopy was used to observe the ultrastructure of the lung tissue and the invasion of Cryptococcus. To clarify the effect of THC, we examined claudin-4, c-Jun, and Smad2 expression. We also measured claudin-4 expression in pulmonary specimens from clinical patients. THC reduced cryptococcal cell invasion in the lungs, improved alveolar exudation, and reduced inflammation. Pretreatment with THC suppressed c-Jun and Smad2 expression, resulting in significantly increased claudin-4 levels. In contrast, the expression of claudin-4 in clinical specimens from patients with cryptococcal infection was higher than that in normal specimens. THC enhanced the clearance of C. deneoformans during infection in vivo. We investigated the expression of claudin-4 and the possible mechanism of THC against C. deneoformans infection.


Assuntos
Cryptococcus , Humanos , Claudina-4/metabolismo
13.
Nucleic Acids Res ; 49(5): 2642-2654, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33591308

RESUMO

The CRISPR/Cas9 system is a technology for genome engineering, which has been applied to indel mutations in genes as well as targeted gene deletion and replacement. Here, we describe paired gRNA deletions along the PIGA locus on the human X chromosome ranging from 17 kb to 2 Mb. We found no compelling linear correlation between deletion size and the deletion efficiency, and there is no substantial impact of topologically associating domains on deletion frequency. Using this precise deletion technique, we have engineered a series of designer deletion cell lines, including one with deletions of two X-chromosomal counterselectable (negative selection) markers, PIGA and HPRT1, and additional cell lines bearing each individual deletion. PIGA encodes a component of the glycosylphosphatidylinositol (GPI) anchor biosynthetic apparatus. The PIGA gene counterselectable marker has unique features, including existing single cell level assays for both function and loss of function of PIGA and the existence of a potent counterselectable agent, proaerolysin, which we use routinely for selection against cells expressing PIGA. These designer cell lines may serve as a general platform with multiple selection markers and may be particularly useful for large scale genome engineering projects such as Genome Project-Write (GP-write).


Assuntos
Sistemas CRISPR-Cas , Engenharia Celular , Proteínas de Membrana/genética , Deleção de Sequência , Toxinas Bacterianas/toxicidade , Linhagem Celular , Cromossomos Humanos X , Marcadores Genéticos , Heterozigoto , Humanos , Mutação , N-Acetilglucosaminiltransferases/genética , Proteínas Citotóxicas Formadoras de Poros/toxicidade , RNA/genética
14.
Nano Lett ; 22(7): 2867-2873, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35298183

RESUMO

Comprehending and controlling the stability of glasses is one of the most challenging issues in glass science. Here we explore the microscopic origin of the ultrastability of a Cu-Zr-Al metallic glass (MG). It is revealed that the ultrastable window (0.7-0.8 Tg) of MGs correlates with the enhanced degree of nanoscale-to-mesoscale structural/mechanical heterogeneity and the connection of stability-favored clusters. On one side, the increased fraction of stability-favored clusters promotes the formation of a stable percolating network through a critical percolation transition, which is essential to form ultrastable MG. On the other side, the enhanced heterogeneity arising from an increased distribution in local clusters may promote synergistically a more efficient and frustrated packing of amorphous structure, contributing to the ultrastability. The present work sheds new light on the stability of MGs and provides a step toward next-generation MGs with superior stability and performances.

15.
Int J Cancer ; 150(7): 1091-1100, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34792202

RESUMO

Biomarkers for early detection of pancreatic cancer are in urgent need. To explore systematic circulating metabolites unbalance and identify potential biomarkers for pancreatic cancer in prospective Chinese cohorts, we conducted an untargeted metabolomics study in subjects with incident pancreatic cancer and matched controls (n = 192) from the China Cardiometabolic Disease and Cancer Cohort (4C) Study. We characterized 998 metabolites in baseline serum and calculated 156 product-to-precursor ratios based on the KEGG database. The identified metabolic profiling revealed systematic metabolic network disorders before pancreatic cancer diagnosis. Forty-Five metabolites or product-to-precursor ratios showed significant associations with pancreatic cancer (P < .05 and FDR < 0.1), revealing abnormal metabolism of amino acids (especially alanine, aspartate and glutamate), lipids (especially steroid hormones), vitamins, nucleotides and peptides. A novel metabolite panel containing aspartate/alanine (OR [95% CI]: 1.97 [1.31-2.94]), androstenediol monosulfate (0.69 [0.49-0.97]) and glycylvaline (1.68 [1.04-2.70]) was significantly associated with risk of pancreatic cancer. Area under the receiver operating characteristic curves (AUCs) was improved from 0.573 (reference model of CA 19-9) to 0.721. The novel metabolite panel was validated in an independent cohort with AUC improved from 0.529 to 0.661. These biomarkers may have a potential value in early detection of pancreatic cancer.


Assuntos
Biomarcadores Tumorais/análise , Metabolômica/métodos , Neoplasias Pancreáticas/metabolismo , Idoso , Feminino , Humanos , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Estudos Prospectivos
16.
Hepatology ; 74(6): 3161-3173, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34233041

RESUMO

BACKGROUND AND AIMS: N-nitroso compounds (NOCs) are among the most potent dietary carcinogens. N-nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA), and N-nitrosopiperidine (NPIP) are abundant in foods and carcinogenic to the liver. We investigated the relationship between dietary NOCs and HCC risk. APPROACH AND RESULTS: In this large, hospital-based, case-control study of 827 pathologically or radiologically confirmed HCC cases and 1,013 controls, NOC intake was calculated by linking food frequency questionnaire-derived dietary data with a comprehensive NOC concentration database. Multivariable-adjusted ORs and 95% CIs of HCC by quartiles of NOC consumption were estimated using logistic regression models, with the lowest quartile as the referent. We further investigated joint effects of consuming the highest quartile of NOCs that were associated with increased HCC risk and hepatitis, diabetes, or alcohol drinking on HCC risk. After adjustment for confounding factors, higher intake of NDEA from plant sources (ORQ4 vs. Q1  = 1.58; 95% CI = 1.03-2.41), NDMA from plant sources (ORQ4 vs. Q1  = 1.54; 95% CI = 1.01-2.34), and NPIP (ORQ4 vs. Q1  = 2.52; 95% CI = 1.62-3.94) was associated with increased HCC risk. No association was observed for nitrate or total NOC intake and HCC risk. Higher consumption of HCC-inducing NOCs and positive hepatitis virus status jointly increased the risk of developing HCC. CONCLUSIONS: In conclusion, though some of our findings may indicate the presence of reverse causation owing to lower meat intake among cases with chronic liver diseases before HCC diagnosis, the potent dietary HCC carcinogens, NDEA, NDMA, and NPIP, and their enhanced carcinogenic effects among chronic carriers of hepatitis virus warrant further prospective investigation.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Inquéritos sobre Dietas/estatística & dados numéricos , Exposição Dietética/efeitos adversos , Neoplasias Hepáticas/epidemiologia , Compostos Nitrosos/efeitos adversos , Idoso , Carcinoma Hepatocelular/induzido quimicamente , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Neoplasias Hepáticas/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Fatores de Risco
17.
Hepatology ; 73(6): 2278-2292, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32931023

RESUMO

BACKGROUND AND AIMS: Therapeutic, clinical trial entry and stratification decisions for hepatocellular carcinoma (HCC) are made based on prognostic assessments, using clinical staging systems based on small numbers of empirically selected variables that insufficiently account for differences in biological characteristics of individual patients' disease. APPROACH AND RESULTS: We propose an approach for constructing risk scores from circulating biomarkers that produce a global biological characterization of individual patient's disease. Plasma samples were collected prospectively from 767 patients with HCC and 200 controls, and 317 proteins were quantified in a Clinical Laboratory Improvement Amendments-certified biomarker testing laboratory. We constructed a circulating biomarker aberration score for each patient, a score between 0 and 1 that measures the degree of aberration of his or her biomarker panel relative to normal, which we call HepatoScore. We used log-rank tests to assess its ability to substratify patients within existing staging systems/prognostic factors. To enhance clinical application, we constructed a single-sample score, HepatoScore-14, which requires only a subset of 14 representative proteins encompassing the global biological effects. Patients with HCC were split into three distinct groups (low, medium, and high HepatoScore) with vastly different prognoses (medial overall survival 38.2/18.3/7.1 months; P < 0.0001). Furthermore, HepatoScore accurately substratified patients within levels of existing prognostic factors and staging systems (P < 0.0001 for nearly all), providing substantial and sometimes dramatic refinement of expected patient outcomes with strong therapeutic implications. These results were recapitulated by HepatoScore-14, rigorously validated in repeated training/test splits, concordant across Myriad RBM (Austin, TX) and enzyme-linked immunosorbent assay kits, and established as an independent prognostic factor. CONCLUSIONS: HepatoScore-14 augments existing HCC staging systems, dramatically refining patient prognostic assessments and therapeutic decision making and enrollment in clinical trials. The underlying strategy provides a global biological characterization of disease, and can be applied broadly to other disease settings and biological media.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Índice de Gravidade de Doença , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco
18.
Microb Pathog ; 173(Pt A): 105808, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36183957

RESUMO

Salmonella is a momentously zoonotic and food-borne pathogen that seriously threats human and animal health around the world. Salmonella pathogenicity is closely related to its virulence genes profile. However, conventional virulence gene analysis methods cannot truly reveal whole virulence genes carried by Salmonella. In this study, whole genome sequencing in combination with Virulence Factor Database were applied to investigate whole virulence gene profiles of 243 Salmonella isolates from animals and humans in China from 2004 to 2019. The results showed that a total of 670 virulence genes were identified in Salmonella, among them, 319 virulence genes were found in all the Salmonella tested isolates, and 9 virulence genes were unique to Salmonella. The 670 virulence genes were classified into 14 categories according to their functions, and the genes related to adherence, effector delivery system, immune modulation, motility and nutritional/metabolic factors accounted for 84.63%. Relationships between virulence genes and serovars, sequence types indicated that strains belonged to the same serovar or sequence type had similar virulence genes profiles, however, isolates from different sources, years and locations of isolation had variable virulence gene profiles. In addition, copy number of virulence genes and homologous virulence genes shared with other pathogens were also analyzed in this study. In summary, we investigated pan-genomic virulence gene profiles and molecular epidemiology of Salmonella isolates from humans and animals in China from 2004 to 2019. These findings are beneficial for pathogenic monitoring, investigation of virulence evolution as well as prevention and control of Salmonella.


Assuntos
Salmonelose Animal , Salmonella enterica , Animais , Humanos , Virulência/genética , Salmonelose Animal/epidemiologia , Fatores de Virulência/genética , Salmonella , Genômica
19.
Chemistry ; 28(4): e202103341, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34773313

RESUMO

A new class of large-but-flexible Pd-BIAN-NHC catalysts (BIAN=acenaphthoimidazolylidene, NHC=N-heterocyclic carbene) has been rationally designed to enable the challenging Buchwald-Hartwig amination of coordinating heterocycles. This robust class of BIAN-NHC catalysts permits cross-coupling under practical aerobic conditions of a variety of heterocycles with aryl, alkyl, and heteroarylamines, including historically challenging oxazoles and thiazoles as well as electron-deficient heterocycles containing multiple heteroatoms with BIAN-INon (N,N'-bis(2,6-di(4-heptyl)phenyl)-7H-acenaphtho[1,2-d]imidazol-8-ylidene) as the most effective ligand. Studies on the ligand structure and electronic properties of the carbene center are reported. The study should facilitate the discovery of even more active catalyst systems based on the unique BIAN-NHC scaffold.


Assuntos
Compostos Heterocíclicos , Aminação , Catálise , Ligantes , Paládio
20.
J Nutr ; 152(2): 439-447, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34665254

RESUMO

BACKGROUND: Epidemiological findings on dietary fat intake and risk of pancreatic cancer (PanC) are inconsistent. OBJECTIVES: This study aimed to determine the association between types of dietary fat intake and PanC. METHODS: We conducted a hospital-based case-control study in 957 pathologically confirmed PanC cases and 938 cancer-free controls. Cases and controls were frequency matched by age, sex, and race. Dietary information was collected using a self-administered validated FFQ. Unconditional logistic regression models were used to estimate the ORs and 95% CIs of PanC risk by quintiles of fat intake with the lowest quintile as referent and with adjustment for other risk factors and dietary factors. RESULTS: We observed no difference in (median) intake of total fat standardized for energy among cases versus controls. The multivariable-adjusted OR (95% CI) of the highest versus the lowest quintile of intake (ORQ5 compared with Q1) was 2.51 (1.68-3.72) for fat from animal sources and 0.41 (0.29-0.58) for fat from plant sources. Intakes of total MUFA, total PUFA, and linoleic (n-6) and long chain n-3 fatty acids were inversely associated with PanC (ORQ5 compared with Q1 and 95% CI: 0.55 [0.36-0.82], 0.59 [0.42-0.82], 0.64 [0.43-0.84], and 0.60 [0.42-0.84], respectively). Arachidonic acid (n-6) and several SFAs were positively associated with PanC. CONCLUSION: Although some observed associations with pancreatic cancer risk could be explained by reverse causation, the potential protective associations with intakes of largely plant-derived PUFAs and MUFAs and fish-derived long chain n-3 PUFAs warrant further prospective investigation.


Assuntos
Ácidos Graxos , Neoplasias Pancreáticas , Estudos de Casos e Controles , Gorduras na Dieta , Ingestão de Alimentos , Humanos , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/prevenção & controle , Fatores de Risco
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