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1.
Plant Cell ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701343

RESUMO

Proteome composition is dynamic and influenced by many internal and external cues, including developmental signals, light availability, or environmental stresses. Protein degradation, in synergy with protein biosynthesis, allows cells to respond to various stimuli and adapt by reshaping the proteome. Protein degradation mediates the final and irreversible disassembly of proteins, which is important for protein quality control and to eliminate misfolded or damaged proteins, as well as entire organelles. Consequently, it contributes to cell resilience by buffering against protein or organellar damage caused by stresses. Moreover, protein degradation plays important roles in cell signaling, as well as transcriptional and translational events. The intricate task of recognizing specific proteins for degradation is achieved by specialized systems that are tailored to the substrate's physicochemical properties and subcellular localization. These systems recognize diverse substrate cues collectively referred to as "degrons", which can assume a range of structural configurations. They are molecular surfaces recognized by E3 ligases of the ubiquitin-proteasome system, but can also be considered as general features recognized by other degradation systems, including autophagy or even organellar proteases. Here we provide an overview of the newest developments in the field, delving into the intricate processes of protein recognition and elucidating the pathways through which they are recruited for degradation.

2.
Cell Mol Life Sci ; 81(1): 289, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970696

RESUMO

Congenital human cytomegalovirus (HCMV) infection is a major cause of abnormalities and disorders in the central nervous system (CNS) and/or the peripheral nervous system (PNS). However, the complete pathogenesis of neural differentiation disorders caused by HCMV infection remains to be fully elucidated. Stem cells from human exfoliated deciduous teeth (SHEDs) are mesenchymal stem cells (MSCs) with a high proliferation and neurogenic differentiation capacity. Since SHEDs originate from the neural crest of the early embryonic ectoderm, SHEDs were hypothesized to serve as a promising cell line for investigating the pathogenesis of neural differentiation disorders in the PNS caused by congenital HCMV infection. In this work, SHEDs were demonstrated to be fully permissive to HCMV infection and the virus was able to complete its life cycle in SHEDs. Under neurogenic inductive conditions, HCMV infection of SHEDs caused an abnormal neural morphology. The expression of stem/neural cell markers was also disturbed by HCMV infection. The impairment of neural differentiation was mainly due to a reduction of intracellular cholesterol levels caused by HCMV infection. Sterol regulatory element binding protein-2 (SREBP2) is a critical transcription regulator that guides cholesterol synthesis. HCMV infection was shown to hinder the migration of SREBP2 into nucleus and resulted in perinuclear aggregations of SREBP2 during neural differentiation. Our findings provide new insights into the prevention and treatment of nervous system diseases caused by congenital HCMV infection.


Assuntos
Diferenciação Celular , Colesterol , Infecções por Citomegalovirus , Citomegalovirus , Células-Tronco Mesenquimais , Proteína de Ligação a Elemento Regulador de Esterol 2 , Humanos , Colesterol/metabolismo , Colesterol/biossíntese , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Citomegalovirus/fisiologia , Citomegalovirus/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/virologia , Células-Tronco Mesenquimais/citologia , Células Cultivadas , Dente Decíduo/virologia , Dente Decíduo/citologia , Dente Decíduo/metabolismo , Neurônios/metabolismo , Neurônios/virologia , Neurogênese
3.
Plant Cell Physiol ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896040

RESUMO

BRI1-EMS Suppressor 1 (BES1) and Brassinazole resistant 1 (BZR1) are two highly similar master transcription factors of the brassinosteroid (BR) signaling pathway that regulate a variety of plant growth and development processes as well as stress responses. Previous genetic and biochemical analyses have established a complex regulatory network to control the two transcription factors. This network includes coordination with other transcription factors and interactors, multiple post-translational modifications (PTMs), and differential subcellular localizations. In this review, we systematically detail the functions and regulatory mechanisms of various PTMs: phosphorylation/dephosphorylation, ubiquitination/deubiquitination, SUMOylation/deSUMOylation, oxidation/reduction, in regulating the subcellular localization, protein stability, and the transcriptional activity of BES1/BZR1. We also discuss the current knowledge about the BES1/BZR1-interactors mediating the dynamic nucleocytoplasmic shuttling of BES1 and BZR1.

4.
Clin Gastroenterol Hepatol ; 22(2): 305-314, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37659766

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) has a higher incidence in males, but the association of sex with survival remains controversial. This study aimed to examine the effect of sex on HCC survival and its association with age. METHODS: Among 33,238 patients with HCC from 12 Chinese tertiary hospitals, 4175 patients who underwent curative-intent hepatectomy or ablation were analyzed. Cancer-specific survival (CSS) was analyzed using Cox regression and Kaplan-Meier methods. Two propensity score methods and multiple mediation analysis were applied to mitigate confounding. To explore the effect of estrogen, a candidate sex-specific factor that changes with age, female participants' history of estrogen use, and survival were analyzed. RESULTS: There were 3321 males and 854 females included. A sex-related disparity of CSS was present and showed a typical age-dependent pattern: a female survival advantage over males appeared at the perimenopausal age of 45 to 54 years (hazard risk [HR], 0.77; 5-year CSS, 85.7% vs 70.6%; P = .018), peaked at the early postmenopausal age of 55 to 59 years (HR, 0.57; 5-year CSS, 89.8% vs 73.5%; P = .015), and was not present in the premenopausal (<45 y) and late postmenopausal groups (≥60 y). Consistent patterns were observed in patients after either ablation or hepatectomy. These results were sustained with propensity score analyses. Confounding or mediation effects accounted for only 19.5% of sex survival disparity. Female estrogen users had significantly longer CSS than nonusers (HR, 0.74; 5-year CSS, 79.6% vs 72.5%; P = .038). CONCLUSIONS: A female survival advantage in HCC depends on age, and this may be associated with age-dependent, sex-specific factors.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Hepatectomia , Estrogênios , Pontuação de Propensão , Recidiva Local de Neoplasia/patologia
5.
Eur Radiol ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546792

RESUMO

OBJECTIVE: To evaluate the efficacy, safety, and improvement of symptoms by ultrasound-guided microwave ablation (MWA) for patients with large benign thyroid nodules (BTNs). METHODS: Eighty-seven patients with 87 BTNs (≥ 4 cm) treated with MWA between April 2015 and March 2021 were enrolled in this retrospective multicenter study, with clinical and ultrasound examinations performed at the 1st, 3rd, 6th, and 12th months. A multivariable linear mixed effects model was employed to explore the alterations in volume and volume reduction ratio (VRR), as well as the potential factors associated with VRR. RESULTS: The mean age of the 87 patients was 45.69 ± 14.21 years (range 18-76 years), and the ratio of men to women was 1:4.8. The mean volumes were much decreased at the 12th month after ablation compared to the initial volumes (p < .001). The mean VRR was 76.09% at the 12th month. The technique efficacy (VRR > 50%) was 90.80% at the 12th month. A multivariate analysis revealed that VRR was related to the initial volume (p = .015), annular flow (p = .010), and nodule composition (p = .024). The mean symptomatic score decreased from 4.40 ± 0.28 to 0.26 ± 0.06 at the 12th month (p < .001). At the same time, the mean cosmetic score decreased from 3.22 ± 0.10 to 1.31 ± 0.08 (p < .001). CONCLUSION: MWA could serve as a safe and effective therapy for large BTNs, significantly reducing the volume of BTNs and significantly improving compressive symptoms and appearance problems. CLINICAL RELEVANCE STATEMENT: Microwave ablation could serve as a safe and effective therapy for large benign thyroid nodules, leading to significant volume reduction and satisfied symptom and cosmetic alleviation period. KEY POINTS: • This multicenter study investigated the feasibility and safety of microwave ablation for large benign thyroid nodules. • After ablation, the nodule volume was significantly reduced, and patients' symptoms and appearance problems were significantly improved. • Microwave ablation is feasible for large benign thyroid nodules and has been a supplement treatment.

6.
J Nucl Cardiol ; 34: 101825, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387736

RESUMO

BACKGROUND: It is clinically needed to explore a more efficient imaging protocol for single photon emission computed tomography (SPECT) myocardial blood flow (MBF) quantitation derived from cadmium zinc telluride (CZT) SPECT camera for the routine clinical utilization. METHODS: One hundred and twenty patients with matched clinical characteristics and angiographic findings who completed one-day rest/stress SPECT imaging with either the intermittently sequential imaging (ISI) protocol (two dynamic and two electrocardiography (ECG)-gated scans) or the continuous rapid imaging (CRI) protocol (two dynamic/ECG-gated scans) were included. MBF quantitation adopted residual activity correction (RAC) to correct for rest residual activity (RRA) in the stress dynamic SPECT scan for the detection of flow-limited coronary artery disease. RESULTS: The CRI protocol reduced about 6.2 times shorter than the ISI protocol (25.5 min vs 157.6 min), but slightly higher than the RRA (26.7% ± 3.6% vs 22.3% ± 4.9%). With RAC, both protocols demonstrated close stress MBF (2.18 ± 1.13 vs 2.05 ± 1.10, P > 0.05) and myocardial flow reserve (MFR) (2.42 ± 1.05 vs 2.48 ± 1.11, P > 0.05) to deliver comparable diagnostic performance (sensitivity = 82.1%-92.3%, specificity = 81.2%-91.2%). Myocardial perfusion and left ventricular function overall showed no significant difference (all P > 0.26). CONCLUSION: One-day rest/stress SPECT with the CRI protocol and rest RAC is feasible to warrant the diagnostic performance of MBF quantitation with a shortened examination time and enhanced patient comfort. Further evaluation on the impact of extracardiac activity to regional MBF and perfusion pattern is required. Additional evaluation is needed in a patient population that is typical of those referred for SPECT MPI, including those with known or suspected coronary microvascular disease.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Imagem de Perfusão do Miocárdio , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Cádmio , Estudos de Viabilidade , Imagem de Perfusão do Miocárdio/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Telúrio , Zinco
7.
Inorg Chem ; 63(1): 915-922, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38152032

RESUMO

The hydrogenation of CO2 to high-value-added liquid fuels is crucial for greenhouse gas emission reduction and optimal utilization of carbon resources. Developing supported heterogeneous catalysts is a key strategy in this context, as they offer well-defined active sites for in-depth mechanistic studies and improved catalyst design. Here, we conducted extensive first-principles calculations to systematically explore the reaction mechanisms for CO2 hydrogenation on a heterogeneous bimetal NiAl-deposited metal-organic framework (MOF) NU-1000 and its catalytic performance as atomically dispersed catalysts for CO2 hydrogenation to formic acid (HCOOH), formaldehyde (H2CO), and methanol (CH3OH). The present results reveal that the presence of the NiAl-oxo cluster deposited on NU-1000 efficiently activates H2, and the facile heterolysis of H2 on Ni and adjacent O sites serves as a precursor to the hydrogenation of CO2 into various C1 products HCOOH, H2CO, and CH3OH. Generally, H2 activation is the rate-determining step in the entire CO2 hydrogenation process, the corresponding relatively low free energy barriers range from 14.5 to 15.9 kcal/mol, and the desorption of products on NiAl-deposited NU-1000 is relatively facile. Although the Al atom does not directly participate in the reaction, its presence provides exposed oxygen sites that facilitate the heterolytic cleavage of H2 and the hydrogenation of C1 intermediates, which plays an important role in enhancing the catalytic activity of the Ni site. The present study demonstrates that the catalytic performance of NU-1000 can be finely tuned by depositing heterometal-oxo clusters, and the porous MOF should be an attractive platform for the construction of atomically dispersed catalysts.

8.
Nutr Metab Cardiovasc Dis ; 34(6): 1559-1570, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658225

RESUMO

BACKGROUND AND AIMS: The potential influence of left atrial size on the relationship between uric acid and atrial fibrillation has not been fully investigated. This study aims to evaluate the interaction effect of left atrial size on the association between uric acid and atrial fibrillation in patients with coronary artery disease. METHODS AND RESULTS: This retrospective cohort study, conducted from January 2018 to October 2022, included 2004 patients undergoing Drug-Eluting Stent implantation for coronary artery disease. Utilizing logistic regression models with the product of left atrial enlargement (LAE) and uric acid, interaction effects were assessed. Among the participants, 383 had LAE, and 159 experienced atrial fibrillation. After adjusting for covariates, continuous uric acid levels were associated with an increased risk of atrial fibrillation in patients without LAE (OR:1.631, 95% CI: 1.284-2.072), but not in those with LAE (OR:1.069, 95% CI: 0.848-1.348). A significant interaction of uric acid levels was observed between groups with and without LAE (p = 0.046). Restricted cubic spline curves indicated a J-shaped relationship between uric acid and atrial fibrillation in the absence of LAE. However, the association between uric acid levels and atrial fibrillation in the LAE group remained unchanged with increasing uric acid levels. CONCLUSION: The study suggested that left atrial size modified the association between uric acid and atrial fibrillation in patients with coronary artery disease. Uric acid serves as a potential biomarker for atrial fibrillation risk, especially in individuals without LAE.


Assuntos
Fibrilação Atrial , Biomarcadores , Doença da Artéria Coronariana , Átrios do Coração , Ácido Úrico , Humanos , Fibrilação Atrial/sangue , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Ácido Úrico/sangue , Masculino , Feminino , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Fatores de Risco , Biomarcadores/sangue , Medição de Risco , Intervenção Coronária Percutânea/efeitos adversos , Hiperuricemia/sangue , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Stents Farmacológicos , Remodelamento Atrial , Função do Átrio Esquerdo
9.
BMC Vet Res ; 20(1): 180, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715028

RESUMO

BACKGROUND: Infectious bovine rhinotracheitis (IBR), caused by Bovine alphaherpesvirus-1 (BoAHV-1), is an acute, highly contagious disease primarily characterized by respiratory tract lesions in infected cattle. Due to its severe pathological damage and extensive transmission, it results in significant economic losses in the cattle industry. Accurate detection of BoAHV-1 is of paramount importance. In this study, we developed a real-time fluorescent quantitative PCR detection method for detecting BoAHV-1 infections. Utilizing this method, we tested clinical samples and successfully identified and isolated a strain of BoAHV-1.1 from positive samples. Subsequently, we conducted a genetic evolution analysis on the isolate strain's gC, TK, gG, gD, and gE genes. RESULTS: The study developed a real-time quantitative PCR detection method using SYBR Green II, achieving a detection limit of 7.8 × 101 DNA copies/µL. Specificity and repeatability analyses demonstrated no cross-reactivity with other related pathogens, highlighting excellent repeatability. Using this method, 15 out of 86 clinical nasal swab samples from cattle were found to be positive (17.44%), which was higher than the results obtained from conventional PCR detection (13.95%, 12/86). The homology analysis and phylogenetic tree analysis of the gC, TK, gG, gD, and gE genes of the isolated strain indicate that the JL5 strain shares high homology with the BoAHV-1.1 reference strains. Amino acid sequence analysis revealed that gC, gE, and gG each had two amino acid mutations, while the TK gene had one synonymous mutation and one H to Y mutation, with no amino acid mutations observed in the gD gene. Phylogenetic tree analysis indicated that the JL5 strain belongs to the BoAHV-1.1 genotype and is closely related to American strains such as C33, C14, and C28. CONCLUSIONS: The established real-time fluorescent quantitative PCR detection method exhibits good repeatability, specificity, and sensitivity. Furthermore, genetic evolution analysis of the isolated BoAHV-1 JL-5 strain indicates that it belongs to the BoAHV-1.1 subtype. These findings provide a foundation and data for the detection, prevention, and control Infectious Bovine Rhinotracheitis.


Assuntos
Alphaherpesvirinae , Rinotraqueíte Infecciosa Bovina , Reação em Cadeia da Polimerase em Tempo Real , Rinotraqueíte Infecciosa Bovina/virologia , Animais , Bovinos , Alphaherpesvirinae/classificação , Alphaherpesvirinae/genética , Alphaherpesvirinae/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Sensibilidade e Especificidade , Manejo de Espécimes/veterinária , Filogenia
10.
J Asian Nat Prod Res ; : 1-16, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975978

RESUMO

The flavonoid compound chinonin is one of the main active components of Rhizoma anemarrhena with multiple activities, including anti-inflammatory and antioxidant properties, protection of mitochondrial function and regulation of immunity. In this paper, we reviewed recent research progress on the protective effect of chinonin on brain injury in neurological diseases. "Chinonin" OR "Mangiferin" AND "Nervous system diseases" OR "Neuroprotection" was used as the terms for search in PumMed. After discarding duplicated and irrelevant articles, a total of 23 articles relevant to chinonin published between 2012 and 2023 were identified in our study.

11.
Int J Mol Sci ; 25(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38673976

RESUMO

Antagonist peptides (ANTs) of vasoactive intestinal polypeptide receptors (VIP-Rs) are shown to enhance T cell activation and proliferation in vitro, as well as improving T cell-dependent anti-tumor response in acute myeloid leukemia (AML) murine models. However, peptide therapeutics often suffer from poor metabolic stability and exhibit a short half-life/fast elimination in vivo. In this study, we describe efforts to enhance the drug properties of ANTs via chemical modifications. The lead antagonist (ANT308) is derivatized with the following modifications: N-terminus acetylation, peptide stapling, and PEGylation. Acetylated ANT308 exhibits diminished T cell activation in vitro, indicating that N-terminus conservation is critical for antagonist activity. The replacement of residues 13 and 17 with cysteine to accommodate a chemical staple results in diminished survival using the modified peptide to treat mice with AML. However, the incorporation of the constraint increases survival and reduces tumor burden relative to its unstapled counterpart. Notably, PEGylation has a significant positive effect, with fewer doses of PEGylated ANT308 needed to achieve comparable overall survival and tumor burden in leukemic mice dosed with the parenteral ANT308 peptide, suggesting that polyethylene glycol (PEG) incorporation enhances longevity, and thus the antagonist activity of ANT308.


Assuntos
Leucemia Mieloide Aguda , Receptores de Peptídeo Intestinal Vasoativo , Animais , Camundongos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Receptores de Peptídeo Intestinal Vasoativo/metabolismo , Receptores de Peptídeo Intestinal Vasoativo/antagonistas & inibidores , Humanos , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Linhagem Celular Tumoral
12.
J Environ Manage ; 352: 120048, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38246105

RESUMO

Understanding the porosity of biochar (BC) that promotes the heavy metal (HM) passivation during composting can contribute to the sustainable management of pig manure (PM). The current work aimed to explore the influence of BC with varying pore sizes on the physicochemical properties and morphological changes of HMs (including Zn, Cu, Cr, As, and Hg), and microbiota development during PM composting. The various pore sizes of BC were generated by pyrolyzing pine wood at 400 (T1), 500 (T2), 600 (T3) and 700 (T4) °C, respectively. The results revealed a positive correlation between specific surface area of BC and pyrolysis temperature. BC addition contributed to a significantly extended compost warming rate and duration of high-temperature period, as well as HM passivation, reflected in the decrease in Exc-Zn (63-34%) and Red-Cu (28-13%) content, and the conversion of Oxi-Cr (29-21%) and Red-Hg (16-5%) to more stable forms. Moreover, BC at T4 exhibited the best effect on Zn and Cu passivation due to the highest specific surface area (380.03 m2/g). In addition to its impact on HM passivation, BC addition improved the microbial environment during PM composting, leading to enhanced microbial diversity and richness. Notably, Chloroflexi and Bacteroidota played key roles in promoting the transformation of Exc-Cu and Red-Hg into stable forms. This phenomenon further stimulated the enhanced decomposition of organic matter (OM) when BC prepared at 600-700 °C was added. Therefore, it can be concluded that the regulation of BC porosity is an effective strategy to improve HM passivation and the overall effectiveness of PM composting.


Assuntos
Compostagem , Mercúrio , Metais Pesados , Microbiota , Suínos , Animais , Esterco , Solo , Metais Pesados/análise , Carvão Vegetal/química
13.
Korean J Physiol Pharmacol ; 28(4): 361-377, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38926843

RESUMO

The dried rattan stem of the Fibraurea Recisa Pierre plant contains the active ingredient known as fibrauretine (FN). Although it greatly affects Alzheimer's disease (AD), the mechanism of their effects still remains unclear. Proteomics and transcriptomics analysis methods were used in this study to determine the mechanism of FN in the treatment of AD. AD model is used through bilateral hippocampal injection of Aß1-40. After successful modeling, FN was given for 30 days. The results showed that FN could improve the cognitive dysfunction of AD model rats, reduce the expression of Aß and P-Tau, increase the content of acetylcholine and reduce the activity of acetylcholinesterase. The Kyoto Encyclopedia of Genes and Genomes enriched differentially expressed genes and proteins are involved in signaling pathways including metabolic pathway, AD, pathway in cancer, PI3K-AKT signaling pathway, and cAMP signaling pathway. Transcriptomics and proteomics sequencing resulted in 19 differentially expressed genes and proteins. Finally, in contrast to the model group, after FN treatment, the protein expressions and genes associated with the PI3K-AKT pathway were significantly improved in RT-qPCR and Western blot and assays. This is consistent with the findings of transcriptomic and proteomic analyses. Our study found that, FN may improve some symptoms of AD model rats through PI3K-AKT signaling pathway.

14.
Diabetologia ; 66(12): 2368-2386, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37615690

RESUMO

AIMS/HYPOTHESIS: Insulin resistance is a major pathophysiological defect in type 2 diabetes and obesity. Numerous experimental and clinical studies have provided evidence that sustained lipotoxicity-induced mitophagy deficiency can exacerbate insulin resistance, leading to a vicious cycle between mitophagy dysfunction and insulin resistance, and thereby the onset of type 2 diabetes. Emerging evidence suggests that exosomes (Exos) from M2 macrophages play an essential role in modulating metabolic homeostasis. However, how macrophages are affected by lipotoxicity and the role of lipotoxicity in promoting macrophage activation to the M1 state have not been determined. The objective of this study was to determine whether M1 macrophage-derived Exos polarised by lipopolysaccharide (LPS) + palmitic acid (PA)-induced lipotoxicity contribute to metabolic homeostasis and impact the development of insulin resistance in type 2 diabetes. METHODS: Lipotoxicity-polarised macrophage-derived M1 Exos were isolated from bone marrow (C57BL/6J mouse)-derived macrophages treated with LPS+PA. Exos were characterised by transmission electron microscopy, nanoparticle tracking analysis and western blotting. Flow cytometry, H&E staining, quantitative real-time PCR, immunofluorescence, glucose uptake and output assays, confocal microscopy imaging, western blotting, GTTs and ITTs were conducted to investigate tissue inflammation, mitochondrial function and insulin resistance in vitro and in vivo. The roles of miR-27-3p and its target gene Miro1 (also known as Rhot1, encoding mitochondrial rho GTPase 1) and relevant pathways were predicted and assessed in vitro and in vivo using specific miRNA mimic, miRNA inhibitor, miRNA antagomir and siRNA. RESULTS: miR-27-3p was highly expressed in M1 Exos and functioned as a Miro1-inactivating miRNA through the miR-27-3p-Miro1 axis, leading to mitochondria fission rather than fusion as well as mitophagy impairment, resulting in NOD-like receptor 3 inflammatory activation and development of insulin resistance both in vivo and in vitro. Inactivation of miR-27-3p induced by M1 Exos prevented type 2 diabetes development in high-fat-diet-fed mice. CONCLUSIONS/INTERPRETATION: These findings suggest that the miR-27-3p-Miro1 axis, as a novel regulatory mechanism for mitophagy, could be considered as a new therapeutic target for lipotoxicity-related type 2 diabetes disease development.


Assuntos
Diabetes Mellitus Tipo 2 , Exossomos , Resistência à Insulina , MicroRNAs , Animais , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Exossomos/metabolismo , Resistência à Insulina/genética , Lipopolissacarídeos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Mitocôndrias/metabolismo , Mitofagia
15.
Carcinogenesis ; 44(6): 463-475, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37158456

RESUMO

Circular RNAs (circRNAs) have been accepted to play key roles in the development and progression of mutiple cancers including colorectal cancer (CRC). Here, we identified circ-METTL9, derived from 2 to 4 exons of METTL9 gene, may promote CRC progression by accelerating cell cycle progression. However, the role and mechanism of circ-METTL9 in CRC remains unclear. Based on our data, the expression of circ-METTL9 was significantly upregulated in CRC tissues and markedly increased in advanced tumors in CRC patients. Functional experiments demonstrated that circ-METTL9 overexpression promoted CRC cells proliferation and migration in vitro, and simultaneously enhanced CRC tumor growth and metastasis in vivo. Mechanistically, RNA immunoprecipitation (RIP) assays proved that circ-METTL9 might be a miRNA sponge, and RNA pulldown assays showed the interaction between circ-METTL9 and miR-551b-5p. Notably, cyclin-dependent kinase 6 (CDK6), a key regulator in cell cycle, is a conserved downstream target of miR-551b-5p. Taken together, our findings highlight a novel oncogenic function of circ-METTL9 in CRC progression via circ-METTL9/miR-551b-5p/CDK6 axis, which may serve as a prognostic biomarker and therapeutic target for CRC patients.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Quinase 6 Dependente de Ciclina/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Metiltransferases/metabolismo
16.
Carcinogenesis ; 44(8-9): 682-694, 2023 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-37294054

RESUMO

EphB6 belongs to the receptor tyrosine kinase, whose low expression is associated with shorter survival of colorectal cancer (CRC) patients. But the role and mechanism of EphB6 in the progression of CRC need further study. In addition, EphB6 was mainly expressed in intestinal neurons. But how EphB6 is involved in functions of intestinal neurons has not been known. In our study, we constructed a mouse xenograft model of CRC by injecting CMT93 cells into the rectum of EphB6-deficient mice. We found that the deletion of EphB6 in mice promoted tumor growth of CMT93 cells in a xenograft model of CRC, which was independent of changes in the gut microbiota. Interestingly, inhibition of intestinal neurons by injecting botulinum toxin A into rectum of EphB6-deficient mice could eliminate the promotive effect of EphB6 deficiency on tumor growth in the xenograft model of CRC. Mechanically, the deletion of EphB6 in mice promoted the tumor growth in CRC by increasing GABA in the tumor microenvironment. Furthermore, EphB6 deficiency in mice increased the expression of synaptosomal-associated protein 25 in the intestinal myenteric plexus, which mediated the release of GABA. Our study concluded that EphB6 knockout in mice promotes tumor growth of CMT93 cells in a xenograft model of CRC by modulating GABA release. Our study found a new regulating mechanism of EphB6 on the tumor progression in CRC that is dependent on intestinal neurons.


Assuntos
Comunicação Celular , Neoplasias Colorretais , Humanos , Animais , Camundongos , Neoplasias Colorretais/metabolismo , Intestinos/patologia , Neurônios/metabolismo , Neurônios/patologia , Ácido gama-Aminobutírico , Microambiente Tumoral
17.
Radiology ; 308(2): e223135, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37581502

RESUMO

Background For patients with unresectable colorectal liver metastases (CRLM), clinical guidelines recommend imaging-guided thermal ablation combined with systemic therapy. However, the optimal thermal ablation strategy remains unclear. Purpose To compare long-term outcomes between patients who underwent upfront ablation or delayed ablation for unresectable CRLM. Materials and Methods This retrospective study included patients with unresectable CRLM (three or fewer lesions; diameter, <3 cm) admitted to one of seven hospitals between October 2009 and December 2020. Upfront ablation was performed 2-4 weeks before the start of systemic therapy, and delayed ablation was performed 2-3 months after the start of systemic therapy. Propensity score matching was applied to adjust for differences in baseline variables between groups. Disease-free survival (DFS) was the primary outcome. Overall survival (OS), complications, and adverse events were secondary outcomes. Outcomes were compared between groups by using the log-rank test. Results In total, 255 patients who underwent delayed ablation (mean age, 57 years ± 11 [SD]; 184 men [72%]) and 103 patients who underwent upfront ablation (mean age, 56 years ± 12; 72 men [70%]) were included. After propensity score matching (n = 100 in both groups), the 5-year DFS for patients who underwent upfront ablation was better compared with patients who underwent delayed ablation (36% vs 21%; P = .02). For 5-year OS, no evidence of a difference was observed between ablation strategies (delayed ablation, 59% vs upfront ablation, 64%; P = .49). Additionally, no differences were observed between ablation strategies with respect to the rates of ablative complications (delayed ablation, 6% vs upfront ablation, 5%; P = .76) or drug-related adverse events (delayed and upfront ablation both 9%; P = .99). Conclusion In patients with relatively few (three or fewer) and small (<3 cm) unresectable CRLM, upfront thermal ablation combined with adjuvant systemic therapy led to better DFS compared with delayed ablation. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Georgiades in this issue.


Assuntos
Ablação por Cateter , Neoplasias Colorretais , Neoplasias Hepáticas , Masculino , Humanos , Pessoa de Meia-Idade , Neoplasias Colorretais/patologia , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Terapia Combinada , Hepatectomia , Resultado do Tratamento
18.
Radiology ; 307(5): e221408, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37367448

RESUMO

Background Current guidelines recommend the use of conventional US for risk stratification and management of thyroid nodules. However, fine-needle aspiration (FNA) is often recommended in benign nodules. Purpose To compare the diagnostic performance of multimodality US (including conventional US, strain elastography, and contrast-enhanced US [CEUS]) with the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) in the recommendation of FNA for thyroid nodules to reduce unnecessary biopsies. Materials and Methods In this prospective study, 445 consecutive participants with thyroid nodules from nine tertiary referral hospitals were recruited between October 2020 and May 2021. With univariable and multivariable logistic regression, the prediction models incorporating sonographic features, evaluated with interobserver agreement, were constructed and internally validated with bootstrap resampling technique. In addition, discrimination, calibration, and decision curve analysis were performed. Results A total of 434 thyroid nodules confirmed at pathologic analysis (259 malignant thyroid nodules) in 434 participants (mean age, 45 years ± 12 [SD]; 307 female participants) were included. Four multivariable models incorporated participant age, nodule features at US (proportion of cystic components, echogenicity, margin, shape, punctate echogenic foci), elastography features (stiffness), and CEUS features (blood volume). In recommending FNA in thyroid nodules, the highest area under the receiver operating characteristic curve (AUC) was 0.85 (95% CI: 0.81, 0.89) for the multimodality US model, and the lowest AUC was 0.63 (95% CI: 0.59, 0.68) for TI-RADS (P < .001). At the 50% risk threshold, 31% (95% CI: 26, 38) of FNA procedures could be avoided with multimodality US compared with 15% (95% CI: 12, 19) with TI-RADS (P < .001). Conclusion Multimodality US had better performance in recommending FNA to avoid unnecessary biopsies than the TI-RADS. Clinical trial registration no. NCT04574258 © RSNA, 2023 Supplemental material is available for this article.


Assuntos
Nódulo da Glândula Tireoide , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Biópsia por Agulha Fina , Imagem Multimodal , Estudos Prospectivos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Ultrassonografia/métodos
19.
Radiology ; 309(2): e230949, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37987664

RESUMO

Background Preoperative assessment of follicular thyroid neoplasms is challenging using the current US risk stratification systems (RSSs) that are applicable to papillary thyroid neoplasms. Purpose To develop a US feature-based RSS for differentiating between follicular thyroid adenoma (FTA) and follicular thyroid carcinoma (FTC) in biopsy-proven follicular neoplasm and compare it with existing RSSs. Materials and Methods This retrospective multicenter study included consecutive adult patients who underwent conventional US and received a final diagnosis of follicular thyroid neoplasm from seven centers between January 2018 and December 2022. US images from a pretraining data set were used to improve readers' understanding of the US characteristics of the FTC and FTA. Univariable and multivariable logistic regression analyses were used to assess the association of qualitative US features with FTC in a training data set. Features with P < .05 were used to construct a prediction model (follicular tumor model, referred to as F model) and RSS for follicular neoplasms using the Thyroid Imaging Reporting and Data System (TI-RADS). Area under the receiver operating characteristic curve (AUC) was compared between follicular TI-RADS (hereafter, F-TI-RADS) and existing RSS (American College of Radiology [ACR] TI-RADS, Korean Society of Thyroid Radiology and Korean Society of Radiology TI-RADS [hereafter, referred to as K-TI-RADS], and Chinese TI-RADS [hereafter, referred to as C-TI-RADS]) in a validation data set. Results The pretraining, training, and validation data sets included 30 (mean age, 47.6 years ± 16.0 [SD]; 16 male patients; FTCs, 30 of 60 [50.0%]), 703 (mean age, 47.9 years ± 14.5; 530 female patients; FTCs, 188 of 703 [26.7%]), and 155 (mean age, 49.9 years ± 13.3 [SD]; 155 female patients; FTCs, 43 of 155 [27.7%]) patients. In the validation data set, the F-TI-RADS showed improved performance for differentiating between FTA and FTC (AUC, 0.81; 95% CI: 0.71, 0.86) compared with ACR TI-RADS (AUC, 0.74; 95% CI: 0.66, 0.80; P = .02), K-TI-RADS (AUC, 0.69; 95% CI: 0.61, 0.76; P = .002), and C-TI-RADS (AUC, 0.68; 95% CI: 0.60, 0.75; P = .002). Conclusion F-TI-RADS outperformed existing RSSs for differentiating between FTC and FTA. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Baumgarten in this issue.


Assuntos
Neoplasias da Glândula Tireoide , Adulto , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Projetos de Pesquisa , Medição de Risco
20.
J Nucl Cardiol ; 30(6): 2578-2592, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37434083

RESUMO

BACKGROUND: Clinical use of dynamic myocardial perfusion imaging (D-MPI) of cadmium-zinc-telluride (CZT) cardiac-dedicated SPECT is growing, showing a higher application value than conventional SPECT. The prognostic value of ischemia in patients with non-obstructive coronary arteries (INOCA) remains an important challenge for investigation. The primary objective of this study was to investigate the prognostic value of myocardial flow reserve (MFR) measured with low-dose D-MPI of CZT cardiac-dedicated SPECT in the assessment of patients with INOCA. METHODS: Consecutive screening of patients with INOCA and obstructive coronary artery disease (OCAD) who had coronary angiography (CAG) data was performed within three months before or after D-MPI imaging. The patients who met the inclusion criteria were retrospectively analyzed and follow-up by telephone was performed. The enrolled patients were then divided into the INOCA and OCAD groups. INOCA was defined as signs and/or symptoms of myocardial ischemia but with < 50% epicardial stenosis. OCAD was defined as obstructive stenosis (≥ 50% stenosis) of epicardial coronary arteries or their major branches on the CAG. Medical treatments, Seattle Angina Questionnaire (SAQ) scores, and major adverse cardiac events (MACEs) were studied. The Kaplan-Meier survival curve, Log-rank test, and univariable COX regression analysis were used to evaluate the prognosis of patients and associated predictors, with P < 0.05 being considered statistically significant. RESULTS: A total of 303 patients (159 males and 144 females) were enrolled for the final analysis after excluding 24 patients who were lost to follow-up. The mean age of the included cases was 61.94 ± 8.59 years, of which 203 (67.0%) cases were OCAD and 100 (33.0%) cases were INOCA, respectively. The median follow-up was 16 months (14-21 months). Kaplan-Meier survival curves showed that the incidence of MACE was similar in the INOCA and OCAD groups (log-rank P = 0.2645), while those with reduced MFR showed a higher incidence of MACE than those with normal MFR (log-rank P = 0.0019). The subgroup analysis in the OCAD group revealed that 105 patients with reduced MFR had a higher incidence of MACE than those with normal MFR (log-rank P = 0.0226). The subgroup analysis in the INOCA group showed that 37 patients with reduced MFR had a higher incidence of MACE than those with normal MFR in the INOCA group (log-rank P = 0.0186). Univariable Cox regression analysis showed for every 1 unit increase in MFR, the risk of MACE for INOCA was reduced by 66.1% and that for OCAD by 64.2%. For each 1 mL·g-1·min-1 increase in LV-sMBF, the risk of MACE was reduced by 72.4% in INOCA patients and 63.6% in OCAD patients. CONCLUSIONS: MFR measured with low-dose D-MPI CZT SPECT provides incremental prognostic value in patients with INOCA. Patients with reduced MFR show an increased risk of MACE, increased symptom burdens, and impaired quality of life. INOCA patients with reduced MFR experienced higher rate of MACE than OCAD patients with normal MFR.


Assuntos
Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Prognóstico , Imagem de Perfusão do Miocárdio/métodos , Constrição Patológica , Qualidade de Vida , Estudos Retrospectivos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Isquemia
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