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1.
Mol Cell ; 81(4): 859-869.e8, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352108

RESUMO

Active DNA demethylation via ten-eleven translocation (TET) family enzymes is essential for epigenetic reprogramming in cell state transitions. TET enzymes catalyze up to three successive oxidations of 5-methylcytosine (5mC), generating 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), or 5-carboxycytosine (5caC). Although these bases are known to contribute to distinct demethylation pathways, the lack of tools to uncouple these sequential oxidative events has constrained our mechanistic understanding of the role of TETs in chromatin reprogramming. Here, we describe the first application of biochemically engineered TET mutants that unlink 5mC oxidation steps, examining their effects on somatic cell reprogramming. We show that only TET enzymes proficient for oxidation to 5fC/5caC can rescue the reprogramming potential of Tet2-deficient mouse embryonic fibroblasts. This effect correlated with rapid DNA demethylation at reprogramming enhancers and increased chromatin accessibility later in reprogramming. These experiments demonstrate that DNA demethylation through 5fC/5caC has roles distinct from 5hmC in somatic reprogramming to pluripotency.


Assuntos
5-Metilcitosina/metabolismo , Reprogramação Celular , Proteínas de Ligação a DNA/metabolismo , Embrião de Mamíferos/metabolismo , Elementos Facilitadores Genéticos , Epigênese Genética , Fibroblastos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Dioxigenases , Embrião de Mamíferos/citologia , Fibroblastos/citologia , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Mutação , Células NIH 3T3 , Proteínas Proto-Oncogênicas/genética
2.
Plant J ; 115(5): 1316-1330, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37235700

RESUMO

Increasing concentration of CO2 has significant impacts on many biological processes in plants, and its impact is closely associated with changes in the ratio of photosynthesis to photorespiration. Studies have reported that high CO2 can promote carbon fixing and alleviate plant oxidative damage in response to environmental stresses. However, the effect of high CO2 on fatty acid (FA) metabolism and cellular redox balance in FA-deficient plants is rarely reported. In this study, we identified a high-CO2 -requiring mutant cac2 through forward genetic screening. CAC2 encodes biotin carboxylase, which is one of the subunits of plastid acetyl-CoA carboxylase and participates in de novo FA biosynthesis. Null mutation of CAC2 is embryonic lethal. A point mutation of CAC2 in cac2 mutants produces severe defects in chloroplast development, plant growth and photosynthetic performance. These morphological and physiological defects were largely absent under high CO2 conditions. Metabolite analyses showed that FA contents in cac2-1 leaves were decreased, while photorespiratory metabolites, such as glycine and glycolate, did not significantly change. Meanwhile, cac2 exhibited higher reactive oxygen species (ROS) levels and mRNA expression of stress-responsive genes than the wild-type, indicating that cac2 plants may suffer oxidative stress under ambient CO2 conditions. Elevated CO2 significantly increased FA contents, especially C18:3-FA, and reduced ROS accumulation in cac2-1 leaves. We propose that stress mitigation by high CO2 in cac2 could be due to increased FA levels by promoting carbon assimilation, and the prevention of over-reduction due to decreased photorespiration.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Dióxido de Carbono/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Oxirredução , Fotossíntese/fisiologia , Estresse Oxidativo , Folhas de Planta/metabolismo , Plantas/metabolismo , Carbono/metabolismo , Ácidos Graxos/metabolismo
3.
Am J Physiol Gastrointest Liver Physiol ; 327(2): G123-G139, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38771154

RESUMO

Microtubule-associated serine-threonine kinase-like (MASTL) has recently been identified as an oncogenic kinase given its overexpression in numerous cancers. Our group has shown that MASTL expression is upregulated in mouse models of sporadic colorectal cancer and colitis-associated cancer (CAC). CAC is one of the most severe complications of chronic inflammatory bowel disease (IBD), but a limited understanding of the mechanisms governing the switch from normal healing to neoplasia in IBD underscores the need for increased research in this area. However, MASTL levels in patients with IBD and its molecular regulation in IBD and CAC have not been studied. This study reveals that MASTL is upregulated by the cytokine interleukin (IL)-22, which promotes proliferation and has important functions in colitis recovery; however, IL-22 can also promote tumorigenesis when chronically elevated. Upon reviewing the publicly available data, we found significantly elevated MASTL and IL-22 levels in the biopsies from patients with late-stage ulcerative colitis compared with controls, and that MASTL upregulation was associated with high IL-22 expression. Our subsequent in vitro studies found that IL-22 increases MASTL expression in intestinal epithelial cell lines, which facilitates IL-22-mediated cell proliferation and downstream survival signaling. Inhibition of AKT activation abrogated IL-22-induced MASTL upregulation. We further found an increased association of carbonic anhydrase IX (CAIX) with MASTL in IL-22-treated cells, which stabilized MASTL expression. Inhibition of CAIX prevented IL-22-induced MASTL expression and cell survival. Overall, we show that IL-22/AKT signaling increases MASTL expression to promote cell survival and proliferation. Furthermore, CAIX associates with and stabilizes MASTL in response to IL-22 stimulation.NEW & NOTEWORTHY MASTL is upregulated in colorectal cancer; however, its role in colitis and colitis-associated cancer is poorly understood. This study is the first to draw a link between MASTL and IL-22, a proinflammatory/intestinal epithelial recovery-promoting cytokine that is also implicated in colon tumorigenesis. We propose that IL-22 increases MASTL protein stability by promoting its association with CAIX potentially via AKT signaling to promote cell survival and proliferation.


Assuntos
Interleucina 22 , Interleucinas , Mucosa Intestinal , Interleucinas/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Animais , Proliferação de Células , Transdução de Sinais , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Camundongos , Regulação para Cima , Proteínas Proto-Oncogênicas c-akt/metabolismo , Anidrase Carbônica IX/metabolismo , Anidrase Carbônica IX/genética , Antígenos de Neoplasias
4.
Small ; 20(29): e2311041, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38342590

RESUMO

The directional conversion of methane to ethylene is challenging due to the dissociation of the C─H bond and the self-coupling of methyl intermediates. Herein, a novel W/WO3- x catalyst with the fork vein structure consisting of an alternating arrangement of WO3- x and W is developed. Impressively, the catalyst achieves an unprecedented C2H4 yield of 1822.73 µmol g-1 h-1, with a selectivity of 82.49%. The enhanced catalytic activity is ascribed to the multifunctional synergistic effect induced by oxygen vacancies and W sites in W/WO3- x. Oxygen vacancies provide abundant coordination of unsaturation sites, which promotes the adsorption and activation of CH4, thus reducing the dissociation energy barrier of the C─H bond. The CH2 coupling barrier on the metal W surface is significantly lower compared to WO3, so CH2 can migrate to the W site for coupling. Importantly, the W/WO3- x with high periodicity provides multiple ordered local microelectric fields, and CH2 intermediates with dipole moments undergo orientation polarization and displacement polarization driven by the electric field, thus enabling CH2 migration. This work opens a new avenue for the structural design and modulation of photocatalysts, and provides new perspectives on the migration of methylene between multiple active sites.

5.
Small ; : e2403448, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881353

RESUMO

Alcohol electrooxidation is pivotal for a sustainable energy economy. However, designing efficient electrocatalysts for this process is still a formidable challenge. Herein, palladium-selenium nanowires featuring distinct crystal phases: monoclinic Pd7Se2 and tetragonal Pd4.5Se for ethylene glycol electrooxidation reaction (EGOR) are synthesized. Notably, the supported monoclinic Pd7Se2 nanowires (m-Pd7Se2 NWs/C) exhibit superior EGOR activity, achieving a mass activity (MA) and specific activity (SA) of 10.4 A mgPd -1 (18.7 mA cm-2), which are 8.0 (6.7) and 10.4 (8.2) times versus the tetragonal Pd4.5Se and commercial Pd/C and surpass those reported in the literature. Furthermore, m-Pd7Se2 NWs/C displays robust catalytic activity for other alcohol electrooxidation. Comprehensive characterization and density functional theory (DFT) calculations reveal that the enhanced electrocatalytic performance is attributed to the increased formation of Pd0 on the high-index facets of the m-Pd7Se2 NWs, which lowers the energy barriers for the C─C bond dissociation in CHOHCHOH* and the CO* oxidation to CO2*. This study provides palladium-based alloy electrocatalysts exhibiting the highest mass activity reported to date for the electrooxidation of ethylene glycol, achieved through the crystalline phase engineering strategy.

6.
Small ; 20(10): e2305659, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37884477

RESUMO

Spinal cord injury (SCI) is a severe neurological disorder characterized by significant disability and limited treatment options. Mitigating the secondary inflammatory response following the initial injury is the primary focus of current research in the treatment of SCI. CCL2 (C─C motif chemokine ligand 2) serves as the primary regulator responsible for inflammatory chemotaxis of the majority of peripheral immune cells, blocking the CCL2-CCR2 (C─C chemokine receptor type 2) axis has shown considerable therapeutic potential for inflammatory diseases, including SCI. In this study, it presents a multifunctional biomimetic nanoplatform (CCR2-MM@PLGA/Cur) specifically designed to target the CCL2-CCR2 axis, which consisted of an engineered macrophage membrane (MM) coating with enhanced CCR2 expression and a PLGA (poly (lactic-co-glycolic acid)) nanoparticle that encapsulated therapeutic drugs. CCR2 overexpression on MM not only enhanced drug-targeted delivery to the injury site, but also attenuated macrophage infiltration, microglia pro-inflammatory polarization, and neuronal apoptosis by trapping CCL2. Consequently, it facilitated neural regeneration and motor function recovery in SCI mice, enabling a comprehensive treatment approach for SCI. The feasibility and efficacy of this platform are confirmed through a series of in vitro and in vivo assays, offering new insights and potential avenues for further exploration in the treatment of SCI.


Assuntos
Nanopartículas , Traumatismos da Medula Espinal , Camundongos , Animais , Quimiocina CCL2/metabolismo , Doenças Neuroinflamatórias , Macrófagos/metabolismo , Traumatismos da Medula Espinal/terapia
7.
BMC Cancer ; 24(1): 1033, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169309

RESUMO

OBJECTIVE: Transfer RNA-derived fragments (tRFs) are short non-coding RNA (ncRNA) sequences, ranging from 14 to 30 nucleotides, produced through the precise cleavage of precursor and mature tRNAs. While tRFs have been implicated in various diseases, including cancer, their role in lung adenocarcinoma (LUAD) remains underexplored. This study aims to investigate the impact of tRF-Val-CAC-010, a specific tRF molecule, on the phenotype of LUAD cells and its role in tumorigenesis and progression in vivo. METHODS: The expression level of tRF-Val-CAC-010 was quantified using quantitative real-time polymerase chain reaction (qRT-PCR). Specific inhibitors and mimics of tRF-Val-CAC-010 were synthesized for transient transfection. Cell proliferation was assessed using the Cell Counting Kit-8 (CCK-8), while cell invasion and migration were evaluated through Transwell invasion and scratch assays. Flow cytometry was utilized to analyze cell cycle and apoptosis. The in vivo effects of tRF-Val-CAC-010 on tumor growth and metastasis were determined through tumor formation and metastasis imaging experiments in nude mice. RESULTS: The expression level of tRF-Val-CAC-010 was upregulated in A549 and PC9 LUAD cells (P < 0.01). Suppression of tRF-Val-CAC-010 expression resulted in decreased proliferation of A549 and PC9 cells (P < 0.001), reduced invasion and migration of A549 (P < 0.05, P < 0.001) and PC9 cells (P < 0.05, P < 0.01), enhanced apoptosis in both A549 (P < 0.05) and PC9 cells (P < 0.05), and increased G2 phase cell cycle arrest in A549 cells (P < 0.05). In vivo, the tumor formation volume in the tRF-inhibitor group was significantly smaller than that in the model and tRF-NC groups (P < 0.05). The metastatic tumor flux value in the tRF-inhibitor group was also significantly lower than that in the model and tRF-NC groups (P < 0.05). CONCLUSION: This study demonstrates that tRF-Val-CAC-010 promotes proliferation, migration, and invasion of LUAD cells and induces apoptosis in vitro, however, its specific effects on the cell cycle require further elucidation. Additionally, tRF-Val-CAC-010 enhances tumor formation and metastasis in vivo. Therefore, tRF-Val-CAC-010 may serve as a novel diagnostic biomarker and potential therapeutic target for LUAD.


Assuntos
Adenocarcinoma de Pulmão , Apoptose , Movimento Celular , Proliferação de Células , Neoplasias Pulmonares , Camundongos Nus , Humanos , Animais , Camundongos , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Células A549 , Carcinogênese/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , RNA de Transferência/genética , RNA de Transferência/metabolismo , Metástase Neoplásica
8.
Curr Atheroscler Rep ; 26(9): 511-519, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38976221

RESUMO

PURPOSE OF REVIEW: The risk of incident atherosclerotic cardiovascular disease (ASCVD) in primary prevention is typically lower than in secondary prevention. However, there is a spectrum of risk among individuals undergoing primary prevention with the risk in some individuals approaching those of secondary prevention. We review the clinical conditions wherein the risk in primary prevention is similar to that observed in secondary prevention. RECENT FINDINGS: Among individuals without established ASCVD, coronary artery calcium (CAC) scores ≥ 300 AU are associated with ASCVD event rates similar to secondary prevention populations. CAC score ≥ 1,000 AU are associated with an ASCVD risk seen in very high-risk secondary prevention populations. Interpretation of these observations must however consider differences in the risk reduction strategies. Current guidelines dichotomize ASCVD prevention into primary and secondary prevention, but certain primary prevention patients have an ASCVD risk equivalent to that of secondary prevention populations. Identifying higher risk primary prevention populations will allow for better risk mitigation strategies.


Assuntos
Prevenção Primária , Prevenção Secundária , Humanos , Prevenção Secundária/métodos , Prevenção Primária/métodos , Aterosclerose/prevenção & controle , Fatores de Risco , Medição de Risco , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/epidemiologia , Doença da Artéria Coronariana/prevenção & controle , Doença da Artéria Coronariana/epidemiologia
9.
Diabetes Obes Metab ; 26(9): 3860-3867, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38934214

RESUMO

AIM: The association of overweight/obesity and metabolic dysfunction-associated steatotic liver disease (MASLD) in young adulthood with subclinical atherosclerosis [coronary artery calcification (CAC) and abdominal aortic calcification (AAC)] by middle age is unknown. METHOD: In total, 2274 participants aged 28-39 years from the coronary artery risk development in young adults study at year 10 (1995-1996) who were re-examined 15 years later were included. CAC and AAC were measured at year 25 using computed tomography. We examined the utility of three young adult phenotypes (lean group; overweight/obese group; overweight/obese MASLD group) at year 10 in predicting CAC or AAC by middle age. Modified Poisson regression was used to estimate the association between groups and CAC, and AAC. Independent determinates of CAC and AAC were determined with linear regression models. RESULTS: Compared with individuals categorized as lean in young adulthood, the relative risk for CAC by middle age was 1.09 (95% confidence interval: 0.93-1.28) for those with overweight/obesity and 1.32 (95% confidence interval: 1.08-1.61) for those with overweight/obesity-related MASLD. For AAC, no difference was observed between these three groups. Group, systolic blood pressure and group × systolic blood pressure interaction were all the independent determinates for CAC. CONCLUSION: In this study, young adults with overweight/obesity-related MASLD have a higher risk of developing CAC by middle age. These abnormalities are only partially explained by traditional cardiovascular risk factors, and overweight/obesity-related MASLD has an independent impact on CAC. Our study provides evidence for identifying young adults at higher risk of developing subclinical atherosclerosis.


Assuntos
Doença da Artéria Coronariana , Obesidade , Sobrepeso , Calcificação Vascular , Humanos , Masculino , Feminino , Adulto , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Calcificação Vascular/epidemiologia , Calcificação Vascular/etiologia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/complicações , Obesidade/complicações , Sobrepeso/complicações , Fígado Gorduroso/complicações , Fígado Gorduroso/epidemiologia , Fatores de Risco , Pessoa de Meia-Idade , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/patologia , Adulto Jovem , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia
10.
Conserv Biol ; 38(3): e14273, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38775248

RESUMO

The use of celebrity endorsement in environmental conservation interventions aiming to influence human behavior has increased in recent decades. Although good practice in designing, implementing, and evaluating behavioral interventions is outlined in recent publications, guidance on developing conservation interventions with celebrity endorsement remains limited. To fill this gap, we devised a guide for decision-making relating to celebrity-endorsed behavioral interventions based on the behavioral, project design, and celebrity endorsement literatures. The guide advises conducting research to understand the behavior system in question; defining endorser selection models and celebrities based on the research; developing an endorsement strategy with the appropriate communication channels; testing the celebrity, channels, and strategy with the target audience and making adjustments as needed; and, finally, evaluating the intervention after implementation. We applied this strategy to a case study, the aim of which was to design a celebrity-endorsed intervention to reduce consumption of wild meat in Ho Chi Minh City, Vietnam. Following our guide, we found that employing evidence-based decision-making substantially enhanced our ability to understand the complexity and potential cost associated with using celebrity endorsements in behavioral interventions.


Diseño de intervenciones conductuales para la conservación apoyadas por celebridades Resumen En las últimas décadas se ha incrementado el uso del apoyo de celebridades en las intervenciones de conservación ambiental que buscan influir sobre la conducta humana. Aunque las publicaciones recientes describen las buenas prácticas en el diseño, implementación y evaluación de las intervenciones conductuales, todavía son limitadas las directrices sobre el desarrollo de intervenciones de conservación apoyadas por celebridades. Para llenar este vacío, diseñamos una guía para decidir en relación con las intervenciones conductuales apoyadas por celebridades con base en la literatura sobre las conductas, diseño de proyectos y apoyo de celebridades. La guía recomienda investigar para entender el sistema conductual en cuestión; definir los modelos de selección de patrocinadores y celebridades con base en esta investigación; desarrollar una estrategia de apoyo con los canales adecuados de comunicación; probar los canales, estrategia y celebridades con el público objetivo y realizar los ajustes necesarios; y, por último, la evaluación de la intervención posterior a la implementación. Aplicamos esta estrategia a un estudio de caso, cuyo objetivo era diseñar una intervención con apoyo de celebridades para reducir el consumo de fauna en Ciudad Ho Chi Minh, Vietnam. Con nuestra guía encontramos que el uso de decisiones basadas en evidencias mejoró sustancialmente nuestra capacidad para entender la complejidad y el costo potencial asociado con el uso de apoyo de celebridades en las intervenciones conductuales.


Assuntos
Conservação dos Recursos Naturais , Tomada de Decisões , Conservação dos Recursos Naturais/métodos , Humanos , Vietnã , Carne
11.
BMC Cardiovasc Disord ; 24(1): 204, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600488

RESUMO

BACKGROUND: While coronary artery calcification (CAC) is recognized as a reliable marker for coronary atherosclerosis, the relationship between the concentration of C-reactive protein (CRP) and the incidence and progression of CAC remains controversial. METHOD: PubMed, Embase, Web of Science, and Scopus were systematically searched to identify relevant observational studies until October 2023. The methodological quality of the included studies was evaluated using the Newcastle-Ottawa Scale (NOS). A random-effects meta-analysis was employed to calculate pooled odd ratios (OR) and corresponding 95% confidence intervals, considering heterogeneity among the studies. RESULTS: Out of the 2545 records, 42 cross-sectional and 9 cohort studies were included in the systematic review. The meta-analysis on 12 eligible cross-sectional studies revealed no significant association between CAC and CRP [pooled OR: 1.03 (1.00, 1.06)]. Additionally, an insignificant association was found between CAC and CRP through meta-analysis on three eligible cohort studies [pooled OR: 1.05 (0.95, 1.15)] with no considerable heterogeneity across studies. Sensitivity analyses indicated that the meta-analysis models were robust. There was no evidence of publication bias. CONCLUSION: Based on the meta-analysis findings, elevated levels of CRP did not emerge as a valuable prognostic maker for CAC incidence and progression prediction.


Assuntos
Proteína C-Reativa , Doença da Artéria Coronariana , Calcificação Vascular , Humanos , Proteína C-Reativa/análise , Doença da Artéria Coronariana/diagnóstico , Estudos Transversais , Fatores de Risco , Calcificação Vascular/diagnóstico
12.
BMC Cardiovasc Disord ; 24(1): 96, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336618

RESUMO

An early diagnosis of atherosclerosis, particularly in subclinical status, can play a remarkable role in reducing mortality and morbidity. Because of coronary artery calcification (CAC) nature in radiation exposure, finding biomarkers associated with CAC could be useful in identifying individuals at high risk of CAC score. In this review, we focused on the association of cardiac troponins (hs-cTns) and CAC to achieve insight into the pathophysiology of CAC. In October 2022, we systematically searched Web of Science, Scopus, PubMed, and Embase databases to find human observational studies which have investigated the association of CAC with cardiac troponins. To appraise the included articles, we used the Newcastle Ottawa scale (NOS). Out of 520 records, 10 eligible studies were included. Based on findings from longitudinal studies and cross-sectional analyses, troponin T and I were correlated with occurrence of CAC and its severity. Two of the most important risk factors that affect the correlation between hs-cTns serum levels and CAC were age and gender. The elevation of cardiac troponins may affect the progression of CAC and future cardiovascular diseases. Verifying the association between cardiac troponins and CAC may lead to identify individuals exposed to enhanced risk of cardiovascular disease (CVD) complications and could establish innovative targets for pharmacological therapy.


Assuntos
Biomarcadores , Doença da Artéria Coronariana , Valor Preditivo dos Testes , Calcificação Vascular , Humanos , Calcificação Vascular/sangue , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/diagnóstico , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico , Biomarcadores/sangue , Masculino , Feminino , Medição de Risco , Pessoa de Meia-Idade , Troponina T/sangue , Idoso , Índice de Gravidade de Doença , Prognóstico , Fatores de Risco , Troponina I/sangue , Adulto , Vasos Coronários/diagnóstico por imagem , Angiografia Coronária
13.
Genes Dev ; 30(5): 489-501, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26944676

RESUMO

Metabolic dysfunction contributes to the clinical deterioration observed in advanced cancer patients and is characterized by weight loss, skeletal muscle wasting, and atrophy of the adipose tissue. This systemic syndrome, termed cancer-associated cachexia (CAC), is a major cause of morbidity and mortality. While once attributed solely to decreased food intake, the present description of cancer cachexia is a disorder of multiorgan energy imbalance. Here we review the molecules and pathways responsible for metabolic dysfunction in CAC and the ideas that led to the current understanding.


Assuntos
Caquexia/etiologia , Caquexia/fisiopatologia , Neoplasias/complicações , Tecido Adiposo Branco/fisiopatologia , Metabolismo dos Carboidratos/fisiologia , Sistema Endócrino/fisiopatologia , Humanos , Inflamação/complicações , Metabolismo dos Lipídeos , Fígado/fisiopatologia , Atrofia Muscular/etiologia
14.
Int J Mol Sci ; 25(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38255963

RESUMO

Circulating miRNAs are increasingly being considered as biomarkers in various medical contexts, but the value of analyzing isomiRs (isoforms of canonical miRNA sequences) has not frequently been assessed. Here we hypothesize that an in-depth analysis of the full circulating miRNA landscape could identify specific isomiRs that are stronger biomarkers, compared to their corresponding miRNA, for identifying increased CV risk in patients with non-alcoholic fatty liver disease (NAFLD)-a clinical unmet need. Plasma miRNAs were sequenced with next-generation sequencing (NGS). Liver fat content was measured with magnetic-resonance spectrometry (MRS); CV risk was determined, beyond using traditional biomarkers, by a CT-based measurement of coronary artery calcium (CAC) score and the calculation of a CAC score-based CV-risk percentile (CAC-CV%). This pilot study included n = 13 patients, age > 45 years, with an MRS-measured liver fat content of ≥5% (wt/wt), and free of overt CVD. NGS identified 1103 miRNAs and 404,022 different isomiRs, of which 280 (25%) and 1418 (0.35%), respectively, passed an abundance threshold. Eighteen (sixteen/two) circulating miRNAs correlated positively/negatively, respectively, with CAC-CV%, nine of which also significantly discriminated between high/low CV risk through ROC-AUC analysis. IsomiR-ome analyses uncovered 67 isomiRs highly correlated (R ≥ 0.55) with CAC-CV%. Specific isomiRs of miRNAs 101-3p, 144-3p, 421, and 484 exhibited stronger associations with CAC-CV% compared to their corresponding miRNA. Additionally, while miRNAs 140-3p, 223-3p, 30e-5p, and 342-3p did not correlate with CAC-CV%, specific isomiRs with altered seed sequences exhibited a strong correlation with coronary atherosclerosis burden. Their predicted isomiRs-specific targets were uniquely enriched (compared to their canonical miRNA sequence) in CV Disease (CVD)-related pathways. Two of the isomiRs exhibited discriminative ROC-AUC, and another two showed a correlation with reverse cholesterol transport from cholesterol-loaded macrophages to ApoB-depleted plasma. In summary, we propose a pipeline for exploring circulating isomiR-ome as an approach to uncover novel and strong CVD biomarkers.


Assuntos
Doenças Cardiovasculares , MicroRNA Circulante , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Humanos , Pessoa de Meia-Idade , MicroRNAs/genética , Cálcio , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/genética , Projetos Piloto , Fatores de Risco , Cálcio da Dieta , MicroRNA Circulante/genética , Biomarcadores , Fatores de Risco de Doenças Cardíacas , Colesterol
15.
Cancer Metastasis Rev ; 41(2): 301-316, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35416564

RESUMO

Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer mortality worldwide. Colitis-associated colorectal cancer (CAC) is a subtype of CRC associated with inflammatory bowel disease (IBD). It is well known that individuals with IBD have a 2-3 times higher risk of developing CRC than those who do not, rendering CAC a major cause of death in this group. Although the etiology and pathogenesis of CAC are incompletely understood, animal models of chronic inflammation and human cohort data indicate that changes in the intestinal environment, including host response dysregulation and gut microbiota perturbations, may contribute to the development of CAC. Genomic alterations are a hallmark of CAC, with patterns that are distinct from those in sporadic CRC. The discovery of the biological changes that underlie the development of CAC is ongoing; however, current data suggest that chronic inflammation in IBD increases the risk of developing CAC. Therefore, a deeper understanding of the precise mechanisms by which inflammation triggers genetic alterations and disrupts intestinal homeostasis may provide insight into novel therapeutic strategies for the prevention of CAC.


Assuntos
Neoplasias Colorretais , Doenças Inflamatórias Intestinais , Animais , Carcinogênese , Neoplasias Colorretais/patologia , Humanos , Inflamação/complicações , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Intestinos/patologia
16.
Small ; 19(11): e2205533, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36581562

RESUMO

The 2D graphyne-related scaffolds linked by carbon-carbon triple bonds have demonstrated promising applications in the field of catalysis and energy storage due to their unique features including high conductivity, permanent porosity, and electron-rich properties. However, the construction of related scaffolds is still mainly limited to the cross-linking of CaC2 with multiple substituted aromatic halogens and there is still a lack of efficient methodology capable of introducing high-concentration heteroatoms within the architectures. The development of alternative and facile synthesis procedures to afford nitrogen-abundant graphyne materials is highly desirable yet challenging in the field of energy storage, particularly via the facile mechanochemical procedure under neat and ambient conditions. Herein, graphyne materials with abundant nitrogen-containing species (nitrogen content of 6.9-29.3 wt.%), tunable surface areas (43-865 m2  g-1 ), and hierarchical porosity are produced via the mechanochemistry-driven pathway by deploying highly electron-deficient multiple substituted aromatic nitriles as the precursors, which can undergo cross-linking reaction with CaC2 to afford the desired nitrogen-doped graphyne scaffolds efficiently. Unique structural features of the as-synthesized materials contributed to promising performance in supercapacitor-related applications, delivering high capacitance of 254.5 F g-1 at 5 mV s-1 , attractive rate performance, and good long-term stability.

17.
Cardiovasc Diabetol ; 22(1): 33, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36793073

RESUMO

BACKGROUND: The 2019 guidelines for cardiovascular risk stratification by the European Society of Cardiology and European Association for the Study of Diabetes (ESC-EASD) suggested screening for silent coronary disease in very high risk patients with severe target organ damage (TOD) (i.e. peripheral occlusive arterial disease or severe nephropathy) or high coronary artery calcium (CAC) score. This study aimed to test the validity of this strategy. METHODS: In this retrospective study, we included 385 asymptomatic patients with diabetes and no history of coronary disease but with TOD or ≥ 3 risk factors in addition to diabetes. CAC score was measured using computed tomography scan and a stress myocardial scintigraphy was performed to detect silent myocardial ischemia (SMI), with subsequent coronary angiography in those with SMI. Various strategies to select patients to be screened for SMI were tested. RESULTS: CAC score was ≥ 100 Agatston units (AU) in 175 patients (45.5%). SMI was present in 39 patients (10.1%) and among the 30 patients who underwent angiography, 15 had coronary stenoses and 12 had a revascularization procedure. The most effective strategy consisted in performing myocardial scintigraphy in the 146 patients with severe TOD and, among the 239 other patients without severe TOD, in those with CAC ≥ 100 AU: this strategy provided 82% sensitivity for SMI diagnosis, and identified all the patients with stenoses. CONCLUSION: The ESC-EASD guidelines suggesting SMI screening in asymptomatic patients with very high risk assessed by severe TOD or high CAC score appears effective and could identify all the patients with stenoses eligible for revascularization.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus , Isquemia Miocárdica , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Estudos Retrospectivos , Constrição Patológica/complicações , Isquemia Miocárdica/diagnóstico , Fatores de Risco , Angiografia Coronária/efeitos adversos
18.
Curr Atheroscler Rep ; 25(4): 167-180, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36808390

RESUMO

PURPOSE OF REVIEW: Imaging of adverse coronary plaque features by coronary computed tomography angiography (CCTA) has advanced greatly and at a fast pace. We aim to describe the evolution, present and future in plaque analysis, and its value in comparison to plaque burden. RECENT FINDINGS: Recently, it has been demonstrated that in addition to plaque burden, quantitative and qualitative assessment of coronary plaque by CCTA can improve the prediction of future major adverse cardiovascular events in diverse coronary artery disease scenarios. The detection of high-risk non-obstructive coronary plaque can lead to higher use of preventive medical therapies such as statins and aspirin, help identify culprit plaque, and differentiate between myocardial infarction types. Even more, over traditional plaque burden, plaque analysis including pericoronary inflammation can potentially be useful tools for tracking disease progression and response to medical therapy. The identification of the higher risk phenotypes with plaque burden, plaque characteristics, or ideally both can allow the allocation of targeted therapies and potentially monitor response. Further observational data are now required to investigate these key issues in diverse populations, followed by rigorous randomized controlled trials.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Placa Aterosclerótica , Humanos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Angiografia por Tomografia Computadorizada/métodos , Valor Preditivo dos Testes , Vasos Coronários/diagnóstico por imagem
19.
Curr Atheroscler Rep ; 25(12): 911-920, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37971683

RESUMO

PURPOSE OF REVIEW: To discuss and review the technical considerations, fundamentals, and guideline-based indications for coronary artery calcium scoring, and the use of other non-invasive imaging modalities, such as extra-coronary calcification in cardiovascular risk prediction. RECENT FINDINGS: The most robust evidence for the use of CAC scoring is in select individuals, 40-75 years of age, at borderline to intermediate 10-year ASCVD risk. Recent US recommendations support the use of CAC scoring in varying clinical scenarios. First, in adults with very high CAC scores (CAC ≥ 1000), the use of high-intensity statin therapy and, if necessary, guideline-based add-on LDL-C lowering therapies (ezetimibe, PCSK9-inhibitors) to achieve a ≥ 50% reduction in LDL-C and optimally an LDL-C < 70 mg/dL is recommended. In patients with a CAC score ≥ 100 at low risk of bleeding, the benefits of aspirin use may outweigh the risk of bleeding. Other applications of CAC scoring include risk estimation on non-contrast CT scans of the chest, risk prediction in younger patients (< 40 years of age), its value as a gatekeeper for the decision to perform nuclear stress testing, and to aid in risk stratification in patients presenting with low-risk chest pain. There is a correlation between extra-coronary calcification (e.g., breast arterial calcification, aortic calcification, and aortic valve calcification) and incident ASCVD events. However, its role in informing lipid management remains unclear. Identification of coronary calcium in selected patients is the single best non-invasive imaging modality to identify future ASCVD risk and inform lipid-lowering therapy decision-making.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Calcificação Vascular , Adulto , Humanos , Pró-Proteína Convertase 9 , LDL-Colesterol , Cálcio , Medição de Risco/métodos , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/tratamento farmacológico , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/tratamento farmacológico , Aterosclerose/diagnóstico por imagem , Aterosclerose/tratamento farmacológico , Fatores de Risco , Vasos Coronários
20.
Philos Trans A Math Phys Eng Sci ; 381(2248): 20220016, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37031701

RESUMO

The uniform Kruskal theorem extends the original result for trees to general recursive data types. As shown by Freund, Rathjen and Weiermann (Freund, Rathjen, Weiermann 2022 Adv. Math. 400, 108265 (doi:10.1016/j.aim.2022.108265)), it is equivalent to [Formula: see text]-comprehension, over [Formula: see text] with the ascending descending sequence principle ([Formula: see text]). This result provides a connection between finite combinatorics and abstract set existence. The present article sheds further light on this connection. Firstly, we show that the original Kruskal theorem is equivalent to the uniform version for data types that are finitely generated. Secondly, we prove a dichotomy result for a natural variant of the uniform Kruskal theorem. On the one hand, this variant still implies [Formula: see text]-comprehension over [Formula: see text] extended by the chain antichain principle ([Formula: see text]). On the other hand, it becomes weak when [Formula: see text] is removed from the base theory. This article is part of the theme issue 'Modern perspectives in Proof Theory'.

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