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Coenzyme Q10 (CoQ10) is an essential medicinal ingredient. In this study, we obtained a high-yielding mutant strain of CoQ10, VK-2-3, by subjecting R. sphaeroides V-0 (V-0) to a 12C6+ heavy ion beam and high-voltage prick electric field treatment. To investigate the mutation mechanism, the complete genomes of VK-2-3 and V-0 were sequenced. Collinearity analysis revealed that the nicotinamide adenine dinucleotide-dependent dehydrogenase (NAD) gene underwent rearrangement in the VK-2-3 genome. The NAD gene was overexpressed and silenced in V-0, and this construct was named RS.NAD and RS.ΔNAD. The results showed that the titers of CoQ10 in the RS.NAD and RS.ΔNAD increased and decreased by 16.00 and 33.92%, respectively, compared to those in V-0, and these differences were significant. Our results revealed the mechanism by which the VK-2-3 CoQ10 yield increases through reverse metabolic engineering, providing insights for genetic breeding and mechanistic analysis.
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Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disease with a challenging treatment landscape, due to its complex pathogenesis and limited availability of clinical drugs. Ferroptosis, an iron-dependent form of programmed cell death (PCD), stands distinct from apoptosis, necrosis, autophagy, and other cell death mechanisms. Recent studies have increasingly highlighted the role of iron deposition, reactive oxygen species (ROS) accumulation, oxidative stress, as well as systemic Xc- and glutamate accumulation in the antioxidant system in the pathogenesis of amyotrophic lateral sclerosis. Therefore, targeting ferroptosis emerges as a promising strategy for amyotrophic lateral sclerosis treatment. This review introduces the regulatory mechanism of ferroptosis, the relationship between amyotrophic lateral sclerosis and ferroptosis, and the drugs used in the clinic, then discusses the current status of amyotrophic lateral sclerosis treatment, hoping to provide new directions and targets for its treatment.
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Esclerose Lateral Amiotrófica , Ferroptose , Ferroptose/efeitos dos fármacos , Ferroptose/fisiologia , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/patologia , Humanos , Animais , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Ferro/metabolismo , Antioxidantes/uso terapêuticoRESUMO
The implementation of Personal Carbon Trading (PCT) holds promise in facilitating a noteworthy contribution towards the attainment of emissions reduction predicated on consumption patterns and consequently motivating lifestyle modifications. As individual consumption behaviors usually lead to continuous changes in carbon emissions, it is crucial to rethink PCT from a systematic perspective. This review employed a bibliometric analysis of 1423 papers related to PCT, highlighting the key themes of carbon emissions from energy consumption, climate change, and public opinion on policies in the context of PCT. Most of the existing PCT researches focus on theoretical assumptions and public attitudes, while the quantification of carbon emissions and simulation of PCT require further investigation. Furthermore, the concept of Tan Pu Hui is seldom addressed in PCT studies and case analyses. Moreover, there are limited PCT schemes worldwide that can be directly implemented in practice, leading to a scarcity of large-scale, high-participation case studies. To address these gaps, this review proposes a framework to clarify how PCT can stimulate individual emission reductions on the consumption side, comprising two phases, from motivation to behavior and behavior to target. Future endeavors should prioritize the enhancement of the systematic study of the theoretical foundation of PCT, encompassing carbon emissions accounting and policy design, the incorporation of cutting-edge technology, and the reinforcement of integrated policy practice. This review serves as a valuable reference for future research endeavors and policymaking efforts.
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Carbono , Formulação de Políticas , Mudança Climática , Simulação por Computador , Dióxido de Carbono/análise , ChinaRESUMO
The proliferation and myogenic differentiation of muscle stem cells (MuSCs) are important factors affecting muscle development and beef quality. There is increasing evidence that circRNAs can regulate myogenesis. We found a novel circRNA, named circRRAS2 that is significantly upregulated in the differentiation phase of bovine MuSCs. Here, we aimed to determine its roles in the proliferation and myogenic differentiation of these cells. The results showed that circRRAS2 was expressed in several bovine tissues. CircRRAS2 inhibited MuSCs proliferation and promoted myoblast differentiation. In addition, chromatin isolation by using RNA purification and mass spectrometry in differentiated muscle cells identified 52 RNA-binding proteins that could potentially bind to circRRAS2, in order to regulate their differentiation. The results suggest that circRRAS2 could be a specific regulator of myogenesis in bovine muscle.HighlightsCircRRAS2 expression is higher in DM cells than in GM cells.CircRRAS2 could significantly inhibit the proliferation and apoptosis of bovine MuSCs.CircRRAS2 promotes the differentiation of bovine MuSCs into myotubes.CircRRAS2 may exert regulatory effects through multiple RNA binding proteins.
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Células Satélites de Músculo Esquelético , Bovinos , Animais , Diferenciação Celular/genética , Células Cultivadas , Linhagem Celular , Desenvolvimento Muscular/genética , Músculo Esquelético/metabolismo , Proliferação de Células/genéticaRESUMO
BACKGROUND: Retinitis pigmentosa (RP) is a rare, progressive, and hereditary disorder that leads to the progressive loss of vision and visual field, and in some cases blindness. The specific relationship between RP and glaucoma has been debated for decades. METHODS: In this study, we examined a Han RP family with concomitant angle-closure glaucoma (ACG), performed an inductive analysis of their clinical features and assistant results, and applied whole-exome sequencing (WES) technology for a molecular diagnosis. RESULTS: A novel transversion mutation (c.626 T > A) was identified in the peripherin-2 (PRPH2) gene in the proband, resulting in the substitution of Valine to aspartic acid in codon 209. A full ophthalmic examination showed that the proband with the c.626 T > A mutation had a typical RP manifestation, with close angles; however, the proband's elder brother, who lacked the novel mutation, had a normal fundus and open angles. CONCLUSION: Our results extend the genetic mutation spectrum of PRPH2 in RP, and provide evidence to support a genetic correlation between RP and ACG.
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Glaucoma de Ângulo Fechado , Retinose Pigmentar , Idoso , China , Glaucoma de Ângulo Fechado/genética , Humanos , Masculino , Mutação , Linhagem , Periferinas , Retinose Pigmentar/genéticaRESUMO
Secreted protein acidic and rich in cysteine (SPARC) shows a specific colocalization with limbal epithelial stem cells (LESCs) in vivo; however, the inherent relationship between SPARC and LESCs is still unclear. This study investigated the effects of SPARC on the maintenance of LESC stemness and corneal wound healing. To test the influence of different concentration of exogenous SPARC on the proliferation of LESCs, cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine staining were performed and the results indicated that 1 µg/mL SPARC was the optimum concentration for enhanced LESC proliferation. Compared with a control group, SPARC-treated group showed a higher expression of LESC-positive markers p63α, ABCG-2, and Bmi-1, and a lower level of differentiation marker cytokeratin-3 (CK3), thereby suggesting that SPARC could maintain LESC characteristic phenotype and suppress spontaneous epithelial differentiation in vitro. In vivo, exogenous SPARC accelerated the wound-healing process by both the enhancement of LESC proliferation and promoting the migration of the proliferating cells. However, the intact epithelium impaired this function of SPARC by contact inhibition.
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Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Epitélio Corneano/efeitos dos fármacos , Osteonectina/farmacologia , Células-Tronco/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Western Blotting , Células Cultivadas , Células Epiteliais/citologia , Epitélio Corneano/fisiopatologia , Humanos , Limbo da Córnea/citologia , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Coelhos , Células-Tronco/citologia , Células-Tronco/metabolismoRESUMO
This article considers a general model of distributed convex optimization with possibly local constraints, coupled equality constraints, and coupled inequality constraints, where the coupled equality constraints are affine and the coupled inequality constraints can be nonaffine. To solve this problem, we present two algorithms. The first algorithm is similar to a dual subgradient algorithm that requires a center node in the network. The main advantage of the first algorithm is that it achieves the optimal convergence rate O([1/âk]) . Moreover, it does not require additional treatment for the primal recovery. These merits are achieved by using an iterate-averaging feedback technique on the basis of the dual subgradient method. The second algorithm further removes the requirement of a center node by employing consensus tracking iterates. As a result, the second algorithm is fully distributed at the price of achieving an O([lnk/âk]) convergence rate.
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The purpose of this study was to investigate the effects of secreted protein acidic and rich in cysteine (SPARC) on the maintenance of limbal epithelial stem cell (LESC) stemness and restoration of ocular surface. To determine the suitable concentration of SPARC for LESC culture, the marker expression, mitogenic effect, and holoclone-forming capacity of LESCs treated with different concentrations of SPARC were analyzed. To investigate the mechanism of SPARC's action on the preservation of LESCs stemness, the phosphorylation of related signaling pathways was evaluated by Western blotting. A corneal wound model was established to verify the function of SPARC in ocular surface repair. Consecutive subculturing, colony-forming efficiency, immunofluorescence, and 5-ethynyl-2-deoxyuridine incorporation assays indicated that 1 µg/mL SPARC was a suitable concentration to stimulate LESC proliferation and preserve their proliferative potential. Compared with a control group, 1 µg/mL SPARC effectively increased the expression of ABCG-2, Bmi-1, and Ki67, while decreasing that of CK3/12. The mitogenic effect of SPARC on LESCs was found to be mediated by the phosphorylation of c-Jun N-terminal kinase (JNK) and p38-MAPK signaling pathways, whereas the inhibitors of JNK and p38 MAPK reduced the marker expression and mitogenic capacity of LESCs. In a corneal injury model, SPARC facilitated corneal epithelial wound healing and promoted the proliferation of p63α-positive cells both in the limbus and in the epithelial healing front. SPARC promotes proliferation while suppressing spontaneous differentiation of LESCs through JNK and p38-MAPK signaling pathways, suggesting that SPARC is a promising factor for the improvement of LESCs culture in vitro and in vivo.
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Células Epiteliais/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Limbo da Córnea/metabolismo , Osteonectina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Células 3T3 , Animais , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Epiteliais/citologia , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , CoelhosRESUMO
Here we investigate single-cell stochastic gene expression kinetics in a minimal coupled gene circuit with positive-plus-negative feedback. A triphasic stochastic bifurcation is observed upon increasing the ratio of the positive and negative feedback strengths, which reveals a strong synergistic interaction between positive and negative feedback loops. We discover that coupled positive-plus-negative feedback amplifies gene expression mean but reduces gene expression noise over a wide range of feedback strengths when promoter switching is relatively slow, stabilizing gene expression around a relatively high level. In addition, we study two types of macroscopic limits of the discrete chemical master equation model: the Kurtz limit applies to proteins with large burst frequencies and the Lévy limit applies to proteins with large burst sizes. We derive the analytic steady-state distributions of the protein abundance in a coupled gene circuit for both the discrete model and its two macroscopic limits, generalizing the results obtained by Liu et al. [Chaos 26, 043108 (2016)CHAOEH1054-150010.1063/1.4947202]. We also obtain the analytic time-dependent protein distribution for the classical Friedman-Cai-Xie random bursting model [Friedman, Cai, and Xie, Phys. Rev. Lett. 97, 168302 (2006)PRLTAO0031-900710.1103/PhysRevLett.97.168302]. Our analytic results are further applied to study the structure of gene expression noise in a coupled gene circuit, and a complete decomposition of noise in terms of five different biophysical origins is provided.
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Retroalimentação Fisiológica , Regulação da Expressão Gênica , Modelos Genéticos , Análise de Célula Única , Cinética , Biossíntese de Proteínas , Processos EstocásticosRESUMO
In recent years, microRNAs (miRNAs) are attracting an increasing amount of researchers' attention, as accumulating studies show that miRNAs play important roles in various basic biological processes and that dysregulation of miRNAs is connected with diverse human diseases, particularly cancers. However, the experimental methods to identify associations between miRNAs and diseases remain costly and laborious. In this study, we developed a computational method named Network Distance Analysis for MiRNA-Disease Association prediction (NDAMDA) which could effectively predict potential miRNA-disease associations. The highlight of this method was the use of not only the direct network distance between 2 miRNAs (diseases) but also their respective mean network distances to all other miRNAs (diseases) in the network. The model's reliable performance was certified by the AUC of 0.8920 in global leave-one-out cross-validation (LOOCV), 0.8062 in local LOOCV and the average AUCs of 0.8935 ± 0.0009 in fivefold cross-validation. Moreover, we applied NDAMDA to 3 different case studies to predict potential miRNAs related to breast neoplasms, lymphoma, oesophageal neoplasms, prostate neoplasms and hepatocellular carcinoma. Results showed that 86%, 72%, 86%, 86% and 84% of the top 50 predicted miRNAs were supported by experimental association evidence. Therefore, NDAMDA is a reliable method for predicting disease-related miRNAs.
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Algoritmos , Biologia Computacional/métodos , Redes Reguladoras de Genes , Estudos de Associação Genética , Predisposição Genética para Doença , MicroRNAs/genética , Área Sob a Curva , Feminino , Humanos , MicroRNAs/metabolismo , Neoplasias/genéticaRESUMO
BACKGROUND: A retrospective analysis of patients undergoing cancer surgery suggested that using local anesthetics could reduce cancer recurrence and improve survival rate. Previous studies have indicated that local anesthetics may induce apoptosis in several kinds of cells in vitro, but the mechanism is unclear. METHODS: Cell viability was analyzed by MTS; reactive oxygen species (ROS), mitochondrial membrane potential (MMP, ∆Ψm), cell cycle distribution, and cell apoptosis assay were detected by flow cytometry; DNA damage was measured by comet assay; cell invasion and migration were observed by microscopy; The expression level of related proteins was detected by western blot assay. RESULTS: The results indicated that lidocaine and ropivacaine could decrease viability, induce G0/G1 phase arrest and apoptosis in human non-small cell lung cancer (NSCLC) cells A549 and H520. Invasion and migration were suppressed. Western blot indicated the related apoptotic pathways proteins changed accordingly. Additionally, lidocaine and ropivacaine downregulated ∆Ψm, provoked DNA damage, upregulated ROS production and activated mitogen-activated protein kinase (MAPK) pathways in A549 and H520 cells. CONCLUSIONS: The cytotoxic effect of amide-linked local anesthetics on NSCLC cells were mainly due to apoptosis. The antitumor mechanism of lidocaine and ropivacaine may involve apoptotic pathways and MAPK pathways.
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BACKGROUND AND AIMS: EGFR activation and PKM2 expression are instrumental in tumorigenesis. EGFR activation regulates PKM2 functions in a subcellular compartment-dependent manner and promotes gene transcription and tumor growth. In addition, PKM2 is upregulated in EGFR-induced pathways in glioma malignancies. However, we found that PKM2 could also regulate the activity of the EGF/EGFR signaling pathway in gastric cancer cells. We aimed to define the biological mechanisms for PKM2 in regulating the cell motility and invasion. METHODS: We employed stable transfection with short hairpin RNA to stably silence the expression of PKM2 in the BGC823, SGC7901 and AGS gastric cancer cell lines. The effects of PKM2 in vitro were determined by assessing cell migration and invasion. Immunohistochemical analysis was used to explore the relationship among PKM2 and other proteins. RESULTS: Our results indicate that the knockdown of PKM2 decreased the activity of E-cadherin and enhanced the EGF/EGFR signaling pathway in the gastric cell lines BGC823 and SGC7901 that were positive for E-cadherin expression. However, in the undifferentiated gastric carcinoma cell line AGS, which lacks E-cadherin expression, PKM2 promoted cell migration and invasion. Immunohistochemical analyses showed that the levels of E-cadherin expression, ERK1/2 phosphorylation, and cytoplasmic PKM2 expression were correlated with each other. CONCLUSION: PKM2 may play different roles in differently differentiated gastric cancer cell types, and this finding would be consistent with the previous clinical research. The results of our study reveal an important link between PKM2 and E-cadherin during EGFR-stimulated gastric cancer cell motility and invasion.
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Caderinas/genética , Proteínas de Transporte/genética , Fator de Crescimento Epidérmico/genética , Receptores ErbB/genética , Proteínas de Membrana/genética , Neoplasias Gástricas/genética , Hormônios Tireóideos/genética , Caderinas/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/genética , Proteínas de Membrana/metabolismo , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Fosforilação/genética , Transdução de Sinais/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Hormônios Tireóideos/metabolismo , Proteínas de Ligação a Hormônio da TireoideRESUMO
Human noroviruses (NoVs) are an important cause of epidemic acute gastroenteritis. Their role in sporadic cases, however, is less clear. In this study, we performed a two-year surveillance (September 2005 to August 2007) of NoV gastroenteritis in outpatient clinics in a southern city of China, Jiangmen City. NoVs were detected in 115 patients (115/881, 13.1%) with 30 (26.1%) co-infections with rotaviruses. Sequence analysis showed that all 115 NoVs belonged to genogroup II, with GII.4 being the most predominant (87.8%). NoV-associated infection can be seen year-around, with autumn and winter peaks. This study provides basic information on sporadic cases of major NoV gastroenteritis in children in different seasons, which is valuable for future disease control and prevention.
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Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Norovirus/genética , Infecções por Caliciviridae/epidemiologia , Pré-Escolar , China/epidemiologia , Fezes/virologia , Gastroenterite/epidemiologia , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , Filogenia , Estações do Ano , Fatores de TempoRESUMO
During the past few decades, biomedical modeling techniques have been applied to improve performance of a wide variety of medical systems that require monitoring and control. Diabetes is one of the most important medical problems. This paper focuses on designing a state feedback controller with observer to improve the performance of the insulin control for type 'I' diabetic patients. The dynamic model of glucose levels in diabetic patients is a nonlinear model. The system is a typical fourth-order single-input-single-output state space model. Using a linear time invariant controller based on an operating condition is a common method to simplify control design. On the other hand, adaptive control can potentially improve system performance. But it increases control complexity and may create further stability issues. This paper investigates patient models and presents a simplified control scheme using observer-based feedback controllers. By comparing different control schemes, it shows that a properly designed state feedback controller with observer can eliminate the adaptation strategy that the Proportional-Integral-Derivative (PID) controllers need to improve the control performance. Control strategies are simulated and their performance is evaluated in MATLAB and Simulink.
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Anesthesia drugs have impact on multiple outcomes of an anesthesia patient. Most typical outcomes include anesthesia depth, blood pressures, heart rates, etc. Traditional diagnosis and control in anesthesia focus on a one-drug-one-outcome scenario. This paper studies the problem of real-time modeling for monitoring, diagnosing, and predicting multiple outcomes of anesthesia patients. It is shown that consideration of multiple outcomes is necessary and beneficial for anesthesia managements. Due to limited real-time data, real-time modeling in multi-outcome modeling requires low-complexity model strucrtures. This paper introduces a method of decision-oriented modeling that significantly reduces the complexity of the problem. The method employs simplified and combined model functions in a Wiener structure to contain model complexity. The ideas of drug impact prediction and reachable sets are introduced for utility of the models in diagnosis, outcome prediction, and decision assistance. Clinical data are used to evaluate the effectiveness of the method.
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This paper studies the problem of outcome prediction in anesthesia procedures. Anesthesia depth and blood pressures are used as typical outcomes in this study. Traditional diagnosis and control in anesthesia focus on a one-drug-one-outcome scenario. It is well understood, however, that consideration of multiple outcomes is necessary and beneficial for anesthesia managements. This paper introduces a method of modeling that significantly reduces the complexity of the problem and yet retains model accuracy. Utility of the modeling method is demonstrated in the areas of anesthesia outcome prediction and decision assistance.