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Although most cervical human papillomavirus type 16 (HPV16) infections become undetectable within 1-2 years, persistent HPV16 causes half of all cervical cancers. We used a novel HPV whole-genome sequencing technique to evaluate an exceptionally large collection of 5,570 HPV16-infected case-control samples to determine whether viral genetic variation influences risk of cervical precancer and cancer. We observed thousands of unique HPV16 genomes; very few women shared the identical HPV16 sequence, which should stimulate a careful re-evaluation of the clinical implications of HPV mutation rates, transmission, clearance, and persistence. In case-control analyses, HPV16 in the controls had significantly more amino acid changing variants throughout the genome. Strikingly, E7 was devoid of variants in precancers/cancers compared to higher levels in the controls; we confirmed this in cancers from around the world. Strict conservation of the 98 amino acids of E7, which disrupts Rb function, is critical for HPV16 carcinogenesis, presenting a highly specific target for etiologic and therapeutic research.
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Alphapapillomavirus/genética , Alphapapillomavirus/isolamento & purificação , Carcinoma/virologia , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Adulto , Alphapapillomavirus/classificação , Estudos de Casos e Controles , Feminino , Genoma Viral , Humanos , Pessoa de Meia-Idade , Proteínas E7 de Papillomavirus/genética , Polimorfismo de Nucleotídeo Único , Adulto JovemRESUMO
Mosaic loss of the X chromosome (mLOX) is the most common clonal somatic alteration in leukocytes of female individuals1,2, but little is known about its genetic determinants or phenotypic consequences. Here, to address this, we used data from 883,574 female participants across 8 biobanks; 12% of participants exhibited detectable mLOX in approximately 2% of leukocytes. Female participants with mLOX had an increased risk of myeloid and lymphoid leukaemias. Genetic analyses identified 56 common variants associated with mLOX, implicating genes with roles in chromosomal missegregation, cancer predisposition and autoimmune diseases. Exome-sequence analyses identified rare missense variants in FBXO10 that confer a twofold increased risk of mLOX. Only a small fraction of associations was shared with mosaic Y chromosome loss, suggesting that distinct biological processes drive formation and clonal expansion of sex chromosome missegregation. Allelic shift analyses identified X chromosome alleles that are preferentially retained in mLOX, demonstrating variation at many loci under cellular selection. A polygenic score including 44 allelic shift loci correctly inferred the retained X chromosomes in 80.7% of mLOX cases in the top decile. Our results support a model in which germline variants predispose female individuals to acquiring mLOX, with the allelic content of the X chromosome possibly shaping the magnitude of clonal expansion.
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Aneuploidia , Cromossomos Humanos X , Células Clonais , Leucócitos , Mosaicismo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alelos , Doenças Autoimunes/genética , Bancos de Espécimes Biológicos , Segregação de Cromossomos/genética , Cromossomos Humanos X/genética , Cromossomos Humanos Y/genética , Células Clonais/metabolismo , Células Clonais/patologia , Exoma/genética , Proteínas F-Box/genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa , Leucemia/genética , Leucócitos/metabolismo , Modelos Genéticos , Herança Multifatorial/genética , Mutação de Sentido Incorreto/genéticaRESUMO
Caspases are often considered the final checkpoint for a pathogen to save its replicative niche from collapsing after cell death signaling has been initiated in response to infection. Two recent works (Li et al., 2021; Peng et al., 2022) found that pathogens inhibit host cell death by inactivating multiple caspases with a novel posttranslational modification.
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Caspases , Interações Hospedeiro-Patógeno , Caspases/genética , Caspases/metabolismo , Morte Celular , Replicação do DNARESUMO
Genome-wide association studies (GWASs) have identified numerous lung cancer risk-associated loci. However, decoding molecular mechanisms of these associations is challenging since most of these genetic variants are non-protein-coding with unknown function. Here, we implemented massively parallel reporter assays (MPRAs) to simultaneously measure the allelic transcriptional activity of risk-associated variants. We tested 2,245 variants at 42 loci from 3 recent GWASs in East Asian and European populations in the context of two major lung cancer histological types and exposure to benzo(a)pyrene. This MPRA approach identified one or more variants (median 11 variants) with significant effects on transcriptional activity at 88% of GWAS loci. Multimodal integration of lung-specific epigenomic data demonstrated that 63% of the loci harbored multiple potentially functional variants in linkage disequilibrium. While 22% of the significant variants showed allelic effects in both A549 (adenocarcinoma) and H520 (squamous cell carcinoma) cell lines, a subset of the functional variants displayed a significant cell-type interaction. Transcription factor analyses nominated potential regulators of the functional variants, including those with cell-type-specific expression and those predicted to bind multiple potentially functional variants across the GWAS loci. Linking functional variants to target genes based on four complementary approaches identified candidate susceptibility genes, including those affecting lung cancer cell growth. CRISPR interference of the top functional variant at 20q13.33 validated variant-to-gene connections, including RTEL1, SOX18, and ARFRP1. Our data provide a comprehensive functional analysis of lung cancer GWAS loci and help elucidate the molecular basis of heterogeneity and polygenicity underlying lung cancer susceptibility.
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Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Pulmonares , Polimorfismo de Nucleotídeo Único , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Desequilíbrio de Ligação , Herança Multifatorial/genética , Linhagem Celular Tumoral , Alelos , Células A549RESUMO
Mitochondrial dysfunction causes poorly understood tissue-specific pathology stemming from primary defects in respiration, coupled with altered reactive oxygen species (ROS), metabolic signaling, and apoptosis. The A1555G mtDNA mutation that causes maternally inherited deafness disrupts mitochondrial ribosome function, in part, via increased methylation of the mitochondrial 12S rRNA by the methyltransferase mtTFB1. In patient-derived A1555G cells, we show that 12S rRNA hypermethylation causes ROS-dependent activation of AMP kinase and the proapoptotic nuclear transcription factor E2F1. This retrograde mitochondrial-stress relay is operative in vivo, as transgenic-mtTFB1 mice exhibit enhanced 12S rRNA methylation in multiple tissues, increased E2F1 and apoptosis in the stria vascularis and spiral ganglion neurons of the inner ear, and progressive E2F1-dependent hearing loss. This mouse mitochondrial disease model provides a robust platform for deciphering the complex tissue specificity of human mitochondrial-based disorders, as well as the precise pathogenic mechanism of maternally inherited deafness and its exacerbation by environmental factors.
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Surdez/metabolismo , Modelos Animais de Doenças , Fator de Transcrição E2F1/metabolismo , Animais , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Orelha Interna/patologia , Cistos Glanglionares/patologia , Humanos , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutação , Neurônios/patologia , RNA Ribossômico/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Cochlear inner hair cells (IHCs) are primary sound receptors, and are therefore a target for developing treatments for hearing impairment. IHC regeneration in vivo has been widely attempted, although not yet in the IHC-damaged cochlea. Moreover, the extent to which new IHCs resemble wild-type IHCs remains unclear, as is the ability of new IHCs to improve hearing. Here, we have developed an in vivo mouse model wherein wild-type IHCs were pre-damaged and nonsensory supporting cells were transformed into IHCs by ectopically expressing Atoh1 transiently and Tbx2 permanently. Notably, the new IHCs expressed the functional marker vGlut3 and presented similar transcriptomic and electrophysiological properties to wild-type IHCs. Furthermore, the formation efficiency and maturity of new IHCs were higher than those previously reported, although marked hearing improvement was not achieved, at least partly due to defective mechanoelectrical transduction (MET) in new IHCs. Thus, we have successfully regenerated new IHCs resembling wild-type IHCs in many respects in the damaged cochlea. Our findings suggest that the defective MET is a critical barrier that prevents the restoration of hearing capacity and should thus facilitate future IHC regeneration studies.
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Células Ciliadas Vestibulares , Perda Auditiva , Camundongos , Animais , Células Ciliadas Auditivas Internas , Cóclea/fisiologia , Perda Auditiva/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genéticaRESUMO
The mouse auditory organ cochlea contains two types of sound receptors: inner hair cells (IHCs) and outer hair cells (OHCs). Tbx2 is expressed in IHCs but repressed in OHCs, and neonatal OHCs that misexpress Tbx2 transdifferentiate into IHC-like cells. However, the extent of this switch from OHCs to IHC-like cells and the underlying molecular mechanism remain poorly understood. Furthermore, whether Tbx2 can transform fully mature adult OHCs into IHC-like cells is unknown. Here, our single-cell transcriptomic analysis revealed that in neonatal OHCs misexpressing Tbx2, 85.6% of IHC genes, including Slc17a8, are upregulated, but only 38.6% of OHC genes, including Ikzf2 and Slc26a5, are downregulated. This suggests that Tbx2 cannot fully reprogram neonatal OHCs into IHCs. Moreover, Tbx2 also failed to completely reprogram cochlear progenitors into IHCs. Lastly, restoring Ikzf2 expression alleviated the abnormalities detected in Tbx2+ OHCs, which supports the notion that Ikzf2 repression by Tbx2 contributes to the transdifferentiation of OHCs into IHC-like cells. Our study evaluates the effects of ectopic Tbx2 expression on OHC lineage development at distinct stages of either male or female mice and provides molecular insights into how Tbx2 disrupts the gene expression profile of OHCs. This research also lays the groundwork for future studies on OHC regeneration.
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Células Ciliadas Auditivas Internas , Células Ciliadas Auditivas Externas , Proteínas com Domínio T , Animais , Proteínas com Domínio T/metabolismo , Proteínas com Domínio T/genética , Camundongos , Células Ciliadas Auditivas Internas/metabolismo , Células Ciliadas Auditivas Externas/metabolismo , Feminino , Animais Recém-Nascidos , Transdiferenciação Celular/fisiologia , Transdiferenciação Celular/genética , Masculino , Cóclea/metabolismo , Cóclea/citologia , Camundongos Endogâmicos C57BLRESUMO
Coxiella burnetii is a bacterial pathogen that replicates within host cells by establishing a membrane-bound niche called the Coxiella-containing vacuole. Biogenesis of this compartment requires effectors of its Dot/Icm type IV secretion system. A large cohort of such effectors has been identified, but the function of most of them remain elusive. Here, by a cell-based functional screening, we identified the effector Cbu0513 (designated as CinF) as an inhibitor of NF-κB signaling. CinF is highly similar to a fructose-1,6-bisphosphate (FBP) aldolase/phosphatase present in diverse bacteria. Further study reveals that unlike its ortholog from Sulfolobus tokodaii, CinF does not exhibit FBP phosphatase activity. Instead, it functions as a protein phosphatase that specifically dephosphorylates and stabilizes IκBα. The IκBα phosphatase activity is essential for the role of CinF in C. burnetii virulence. Our results establish that C. burnetii utilizes a protein adapted from sugar metabolism to subvert host immunity.
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Proteínas de Bactérias , Coxiella burnetii , Fosfoproteínas Fosfatases , Febre Q , Transdução de Sinais , Fatores de Virulência , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Chlorocebus aethiops , Coxiella burnetii/genética , Coxiella burnetii/imunologia , Coxiella burnetii/patogenicidade , Células HEK293 , Células HeLa , Humanos , NF-kappa B/genética , NF-kappa B/imunologia , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/imunologia , Febre Q/genética , Febre Q/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Células Vero , Fatores de Virulência/genética , Fatores de Virulência/imunologiaRESUMO
BACKGROUND: Atrial fibrillation (AF) is a highly prevalent condition that can cause or exacerbate heart failure, is an important risk factor for stroke, and is associated with pronounced morbidity and death. Genes uniquely expressed in the atria are known to be essential for maintaining atrial structure and function. Atrial tissue remodeling contributes to arrhythmia recurrence and maintenance. However, the mechanism underlying atrial remodeling remains poorly understood. This study was designed to investigate whether other uncharacterized atrial specific genes play important roles in atrial physiology and arrhythmogenesis. METHODS: RNA-sequencing analysis was used to identify atrial myocyte specific and angiotensin II-responsive genes. Genetically modified, cardiomyocyte-specific mouse models (knockout and overexpression) were generated. In vivo and in vitro electrophysiological, histology, and biochemical analyses were performed to determine the consequences of CIB2 (calcium and integrin binding family member 2 protein) gain and loss of function in the atrium. RESULTS: Using RNA-sequencing analysis, we identified CIB2 as an atrial-enriched protein that is significantly downregulated in the left atria of patients with AF and mouse models of AF from angiotensin II infusion or pressure overload. Using cardiomyocyte-specific Cib2 knockout (Cib2-/-) and atrial myocyte-specific Cib2-overexpressing mouse models, we found that loss of Cib2 enhances AF occurrence, prolongs AF duration, and correlates with a significant increase in atrial fibrosis under stress. Conversely, Cib2 overexpression mitigates AF occurrence and atrial fibrosis triggered by angiotensin II stress. Mechanistically, we revealed that CIB2 competes with and inhibits CIB1-mediated calcineurin activation, thereby negating stress-induced structural remodeling and AF. CONCLUSIONS: Our data suggest that CIB2 represents a novel endogenous and atrial-enriched regulator that protects against atrial remodeling and AF under stress conditions. Therefore, CIB2 may represent a new potential target for treating AF.
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Fibrilação Atrial , Remodelamento Atrial , Animais , Camundongos , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Átrios do Coração , Fibrose , RNA/metabolismoRESUMO
As the most promising hydrogen evolution reaction (HER) electrocatalysts, platinum (Pt)-based catalysts still struggle with sluggish kinetics and expensive costs in alkaline media. Herein, we accelerate the alkaline hydrogen evolution kinetics by optimizing the local environment of Pt species and metal oxide heterointerfaces. The well-dispersed PtRu bimetallic clusters with adjacent MO2-x (M = Sn and Ce) on carbon nanotubes (PtRu/CNT@MO2-x) are demonstrated to be a potential electrocatalyst for alkaline HER, exhibiting an overpotential of only 75 mV at 100 mA cm-2 in 1 M KOH. The excellent mass activity of 12.3 mA µg-1Pt+Ru and specific activity of 32.0 mA cm-2ECSA at an overpotential of 70 mV are 56 and 64 times higher than those of commercial Pt/C. Experimental and theoretical investigations reveal that the heterointerfaces between Pt clusters and MO2-x can simultaneously promote H2O adsorption and activation, while the modification with Ru further optimizes H adsorption and H2O dissociation energy barriers. Then, the matching kinetics between the accelerated elementary steps achieved superb hydrogen generation in alkaline media. This work provides new insight into catalytic local environment design to simultaneously optimize the elementary steps for obtaining ideal alkaline HER performance.
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Although multiple common susceptibility loci for lung cancer (LC) have been identified by genome-wide association studies, they can explain only a small portion of heritability. The etiological contribution of rare deleterious variants (RDVs) to LC risk is not fully characterized and may account for part of the missing heritability. Here, we sequenced the whole exomes of 2777 participants from the Environment and Genetics in Lung cancer Etiology study, a homogenous population including 1461 LC cases and 1316 controls. In single-variant analyses, we identified a new RDV, rs77187983 [EHBP1, odds ratio (OR) = 3.13, 95% confidence interval (CI) = 1.34-7.30, P = 0.008] and replicated two previously reported RDVs, rs11571833 (BRCA2, OR = 2.18; 95% CI = 1.25-3.81, P = 0.006) and rs752672077 (MPZL2, OR = 3.70, 95% CI = 1.04-13.15, P = 0.044). In gene-based analyses, we confirmed BRCA2 (P = 0.007) and ATM (P = 0.014) associations with LC risk and identified TRIB3 (P = 0.009), involved in maintaining genome stability and DNA repair, as a new candidate susceptibility gene. Furthermore, cases were enriched with RDVs in homologous recombination repair [carrier frequency (CF) = 22.9% versus 19.5%, P = 0.017] and Fanconi anemia (CF = 12.5% versus 10.2%, P = 0.036) pathways. Our results were not significant after multiple testing corrections but were enriched in cases versus controls from large scale public biobank resources, including The Cancer Genome Atlas, FinnGen and UK Biobank. Our study identifies novel candidate genes and highlights the importance of RDVs in DNA repair-related genes for LC susceptibility. These findings improve our understanding of LC heritability and may contribute to the development of risk stratification and prevention strategies.
Assuntos
Estudo de Associação Genômica Ampla , Neoplasias Pulmonares , Reparo do DNA/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Células Germinativas , Humanos , Neoplasias Pulmonares/genéticaRESUMO
BACKGROUND: Wilms tumor, also known as nephroblastoma, a pediatric most-frequent malignant-kidney tumor, may be regulated and influenced by transcriptional and epigenetic mechanisms. Chromatin regulatory factors (CRs) play key roles in epigenetic regulation. The present study aimed to explore the involvement of CRs in the development of nephroblastoma. METHODS: RNA-sequencing and clinical information of nephroblastoma samples were obtained by downloading data from the TARGET database. The Limma package was utilized to perform differential expression analysis of genes (DEGs) between the tumor group and the control group. A Venn map was used for intersection of differential genes and CRs and to perform Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of DEGs using the clusterProfiler package. LASSO and Cox analyses were used to construct CR-related risk models and were evaluated based on clinical parameters. A receiver operating characteristic curve was employed to assess the diagnostic performance of risk model. Furthermore, we used a single-sample gene set enrichment analysis algorithm for immune cell infiltration analysis. Finally, to confirm the transcriptome expression of pivotal genes in human nephroblastoma cell lines, a quantitative real-time PCR was employed. RESULTS: Fifteen key CRs were obtained through analysis in nephroblastoma and then the risk model based on 13 important CRs was constructed using the transcriptome data of nephroblastoma. Using the risk model, pediatric nephroblastoma patients were stratified into high- and low-risk groups based on their individual risk scores. The risk score of CRs can predict adverse outcomes in pediatric nephroblastoma, and this gene cluster is closely related to various immunity characteristics of nephroblastoma. Moreover, the nephroblastoma cell line exhibited higher expression levels of prognostic genes (VRK1, ARNTL, RIT1, PRDM6, and TSPY1) compared to the HEK293 T cell line. CONCLUSIONS: The risk characteristics derived from CRs have tremendous significance in predicting prognosis and guiding clinical classification and intervention strategies for pediatric nephroblastoma.
Assuntos
Neoplasias Renais , Tumor de Wilms , Humanos , Criança , Cromatina/genética , Epigênese Genética , Células HEK293 , Tumor de Wilms/genética , Neoplasias Renais/genética , Medição de Risco , Microambiente Tumoral , Proteínas de Ciclo Celular , Proteínas Serina-Treonina Quinases , Peptídeos e Proteínas de Sinalização IntracelularRESUMO
Increasing the sulfur cathode load is an important method for promoting the commercialization of lithium-sulfur batteries. However, there is a common problem of overcharging in high-loading experiments, which is rarely reported. In this work, it is believed that an insulating layer of S8 forms on the current collector surface, hindering electron exchange with polysulfides. Continuous external current input during layer formation can cause irreversible electrode changes and overcharging. The general solution is to provide nucleation centers with adsorption sites to promote the 3D growth of the insulated S8 , thus avoiding overcharging. In this work, a solution is proposed by providing nucleation centers by gallium nitrate, by regulating the 3D growth of S8 away from the surface of the current collector to avoid overcharging and by improving battery performance.
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The uncontrollable growth of lithium dendrites and the flammability of electrolytes are the direct impediments to the commercial application of high-energy-density lithium metal batteries (LMBs). Herein, this study presents a novel approach that combines microencapsulation and electrospinning technologies to develop a multifunctional composite separator (P@AS) for improving the electrochemical performance and safety performance of LMBs. The P@AS separator forms a dense charcoal layer through the condensed-phase flame retardant mechanism causing the internal separator to suffocate from lack of oxygen. Furthermore, it incorporates a triple strategy promoting the uniform flow of lithium ions, facilitating the formation of a highly ion-conducting solid electrolyte interface (SEI), and encouraging flattened lithium deposition with active SiO2 seed points, considerably suppressing lithium dendrites growth. The high Coulombic efficiency of 95.27% is achieved in Li-Cu cells with additive-free carbonate electrolyte. Additionally, stable cycling performance is also maintained with a capacity retention rate of 93.56% after 300 cycles in LFP//Li cells. Importantly, utilizing P@AS separator delays the ignition of pouch batteries under continuous external heating by 138 s, causing a remarkable reduction in peak heat release rate and total heat release by 23.85% and 27.61%, respectively, substantially improving the fire safety of LMBs.
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BACKGROUND: The previous first-in-human study established the preliminary safety and effectiveness of the novel thin-strut iron bioresorbable scaffold (IBS). The current study aims to directly compare the imaging and physiological efficacy, and clinical outcomes of IBS with contemporary metallic drug-eluting stents (DES). METHODS: A total of 518 patients were randomly allocated to treatment with IBS (257 patients) or metallic DES (261 patients) from 36 centers in China. The study is powered to test noninferiority of the IBS compared with the metallic everolimus-eluting stent in terms of the primary endpoint of in-segment late lumen loss at 2 years, and major secondary endpoints including 2-year quantitative flow ratio and cross-sectional mean flow area measured by optical coherence tomography (OCT) (limited to the OCT subgroup, 25 patients in each group). CONCLUSION: This will be the first powered randomized trial investigating the safety and efficacy of the novel thin-strut IBS compared to a contemporary metallic DES. The findings will provide valuable evidence for future research of this kind and the application of metallic bioresorbable scaffolds.
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AIMS: Risk assessment for triple-vessel disease (TVD) remain challenging. Stress hyperglycemia represents the regulation of glucose metabolism in response to stress, and stress hyperglycemia ratio (SHR) is recently found to reflect true acute hyperglycemic status. This study aimed to evaluate the prognostic value of SHR and its role in risk stratification in TVD patients with acute coronary syndrome (ACS). METHODS: A total of 3812 TVD patients with ACS with available baseline SHR measurement were enrolled from two independent centers. The endpoint was cardiovascular mortality. Cox regression was used to evaluate the association between SHR and cardiovascular mortality. The SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) II (SSII) was used as the reference model in the model improvement analysis. RESULTS: During a median follow-up of 5.1 years, 219 (5.8%) TVD patients with ACS suffered cardiovascular mortality. TVD patients with ACS with high SHR had an increased risk of cardiovascular mortality after robust adjustment for confounding (high vs. median SHR: adjusted hazard ratio 1.809, 95% confidence interval 1.160-2.822, P = 0.009), which was fitted as a J-shaped pattern. The prognostic value of the SHR was found exclusively among patients with diabetes instead of those without diabetes. Moreover, addition of SHR improved the reclassification abilities of the SSII model for predicting cardiovascular mortality in TVD patients with ACS. CONCLUSIONS: The high level of SHR is associated with the long-term risk of cardiovascular mortality in TVD patients with ACS, and is confirmed to have incremental prediction value beyond standard SSII. Assessment of SHR may help to improve the risk stratification strategy in TVD patients who are under acute stress.
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Síndrome Coronariana Aguda , Biomarcadores , Glicemia , Doença da Artéria Coronariana , Hiperglicemia , Humanos , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Medição de Risco , Fatores de Tempo , Hiperglicemia/diagnóstico , Hiperglicemia/mortalidade , Hiperglicemia/sangue , Glicemia/metabolismo , Fatores de Risco , Biomarcadores/sangue , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/terapia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , China/epidemiologiaRESUMO
Determination of tipping points in nitrogen (N) isotope (δ15N) natural abundance, especially soil δ15N, with increasing aridity, is critical for estimating N-cycling dynamics and N limitation in terrestrial ecosystems. However, whether there are linear or nonlinear responses of soil δ15N to increases in aridity and if these responses correspond well with soil N cycling remains largely unknown. In this study, we investigated soil δ15N and soil N-cycling characteristics in both topsoil and subsoil layers along a drought gradient across a 3000-km transect of drylands on the Qinghai-Tibetan Plateau. We found that the effect of increasing aridity on soil δ15N values shifted from negative to positive with thresholds at aridity index (AI) = 0.27 and 0.29 for the topsoil and subsoil, respectively, although soil N pools and N transformation rates linearly decreased with increasing aridity in both soil layers. Furthermore, we identified markedly different correlations between soil δ15N and soil N-cycling traits above and below the AI thresholds (0.27 and 0.29 for topsoil and subsoil, respectively). Specifically, in wetter regions, soil δ15N positively correlated with most soil N-cycling traits, suggesting that high soil δ15N may result from the "openness" of soil N cycling. Conversely, in drier regions, soil δ15N showed insignificant relationships with soil N-cycling traits and correlated well with factors, such as soil-available phosphorus and foliage δ15N, demonstrating that pathways other than typical soil N cycling may dominate soil δ15N under drier conditions. Overall, these results highlight that different ecosystem N-cycling processes may drive soil δ15N along the aridity gradient, broadening our understanding of N cycling as indicated by soil δ15N under changing drought regimes. The aridity threshold of soil δ15N should be considered in terrestrial N-cycling models when incorporating 15N isotope signals to predict N cycling and availability under climatic dryness.
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Secas , Ecossistema , Ciclo do Nitrogênio , Isótopos de Nitrogênio , Solo , Solo/química , Isótopos de Nitrogênio/análise , China , Nitrogênio/análise , Nitrogênio/metabolismo , Clima DesérticoRESUMO
Auditory frequency coding is place-specific, which depends on the mechanical coupling of the basilar membrane-outer hair cell (OHC)-tectorial membrane network. Prestin-based OHC electromotility improves cochlear frequency selectivity and sensitivity. Cochlear amplification determines the frequency coding wherein discrete sound frequencies find a 'best' place along the cochlear length. Loss of OHC is the leading cause of age-related hearing loss (ARHL) and is the most common cause of sensorineural hearing loss and compromised speech perception. Lipid interaction with Prestin impacts OHC function. It has been established that high-fat diet (HFD) is associated with ARHL. To determine whether genetic background and metabolism preserve cochlear frequency place coding, we examined the effect of HFD in C57BL/6J (B6) and CBA/CaJ (CBA) on ARHL.We found a significant rescuing effect on ARHL in aged B6 HFD cohort. Prestin levels and cell sizes were better maintained in the experimental B6-HFD group. We also found that distortion product otoacoustic emission (DPOAE) group delay measurement was preserved, which suggested stable frequency place coding. In contrast, the response to HFD in the CBA cohort was modest with no appreciable benefit to hearing threshold. Notably, group delay was shortened with age along with the control. In addition, the frequency dependent OHC nonlinear capacitance gradient was most pronounced at young age but decreased with age. Cochlear RNA-seq analysis revealed differential TRPV1 expression and lipid homeostasis. Activation of TRPV1 and downregulation of arachidonic acid led to downregulation of inflammatory response in B6 HFD, which protects the cochlea from ARHL. The genetic background and metabolic state-derived changes in OHC morphology and function collectively contribute to a redefined cochlear frequency place coding and improved age-related pitch perception.
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Cóclea , Dieta Hiperlipídica , Humanos , Idoso , Dieta Hiperlipídica/efeitos adversos , Ácido Araquidônico , Tamanho Celular , Regulação para BaixoRESUMO
DNA methylation, chromatin accessibility, and gene expression represent different levels information in biological process, but a comprehensive multiomics analysis of the mammalian heart is lacking. Here, we applied nucleosome occupancy and methylome sequencing, which detected DNA methylation and chromatin accessibility simultaneously, as well as RNA-seq, for multiomics analysis of the 4 chambers of adult and fetal human hearts, and adult mouse hearts. Our results showed conserved region-specific patterns in the mammalian heart at transcriptome and DNA methylation level. Adult and fetal human hearts showed distinct features in DNA methylome, chromatin accessibility, and transcriptome. Novel long noncoding RNAs were identified in the human heart, and the gene expression profiles of major cardiovascular diseases associated genes were displayed. Furthermore, cross-species comparisons revealed human-specific and mouse-specific differentially expressed genes between the atria and ventricles. We also reported the relationship among multiomics and found there was a bell-shaped relationship between gene-body methylation and expression in the human heart. In general, our study provided comprehensive spatiotemporal and evolutionary insights into the regulation of gene expression in the heart.
Assuntos
Coração/crescimento & desenvolvimento , Coração/fisiologia , Animais , Cromatina/metabolismo , Ilhas de CpG/genética , DNA/genética , Metilação de DNA/genética , Epigênese Genética/genética , Epigenômica/métodos , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Ventrículos do Coração/crescimento & desenvolvimento , Ventrículos do Coração/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Camundongos , Nucleossomos/metabolismo , Especificidade de Órgãos/genética , RNA Longo não Codificante/metabolismo , Especificidade da Espécie , Transcriptoma/genéticaRESUMO
Researchers are often interested in understanding the disease subtype heterogeneity by testing whether a risk exposure has the same level of effect on different disease subtypes. The polytomous logistic regression (PLR) model provides a flexible tool for such an evaluation. Disease subtype heterogeneity can also be investigated with a case-only study that uses a case-case comparison procedure to directly assess the difference between risk effects on two disease subtypes. Motivated by a large consortium project on the genetic basis of non-Hodgkin lymphoma (NHL) subtypes, we develop PolyGIM, a procedure to fit the PLR model by integrating individual-level data with summary data extracted from multiple studies under different designs. The summary data consist of coefficient estimates from working logistic regression models established by external studies. Examples of the working model include the case-case comparison model and the case-control comparison model, which compares the control group with a subtype group or a broad disease group formed by merging several subtypes. PolyGIM efficiently evaluates risk effects and provides a powerful test for disease subtype heterogeneity in situations when only summary data, instead of individual-level data, is available from external studies due to various informatics and privacy constraints. We investigate the theoretic properties of PolyGIM and use simulation studies to demonstrate its advantages. Using data from eight genome-wide association studies within the NHL consortium, we apply it to study the effect of the polygenic risk score defined by a lymphoid malignancy on the risks of four NHL subtypes. These results show that PolyGIM can be a valuable tool for pooling data from multiple sources for a more coherent evaluation of disease subtype heterogeneity.