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1.
Proc Natl Acad Sci U S A ; 121(11): e2317658121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437537

RESUMO

Identification of mechanisms that program early effector T cells to either terminal effector T (Teff) or memory T (Tm) cells has important implications for protective immunity against infections and cancers. Here, we show that the cytosolic transcription factor aryl hydrocarbon receptor (AhR) is used by early Teff cells to program memory fate. Upon antigen engagement, AhR is rapidly up-regulated via reactive oxygen species signaling in early CD8+ Teff cells, which does not affect the effector response, but is required for memory formation. Mechanistically, activated CD8+ T cells up-regulate HIF-1α to compete with AhR for HIF-1ß, leading to the loss of AhR activity in HIF-1αhigh short-lived effector cells, but sustained in HIF-1αlow memory precursor effector cells (MPECs) with the help of autocrine IL-2. AhR then licenses CD8+ MPECs in a quiescent state for memory formation. These findings partially resolve the long-standing issue of how Teff cells are regulated to differentiate into memory cells.


Assuntos
Linfócitos T CD8-Positivos , Divisão Celular , Citosol , Espécies Reativas de Oxigênio
2.
Biomed Pharmacother ; 172: 116204, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364733

RESUMO

HACE1 is a member of the HECT domain-containing E3 ligases with 909 amino acid residues, containing N-terminal ankyrin-repeats (ANK) and C-terminal HECT domain. Previously, it was shown that HACE1 is inactive in human tumors and plays a crucial role in the initiation, progression, and invasion of malignant tumors. Recent studies indicated that HACE1 might be closely involved in neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Huntington's disease. HACE1 interacts with its substrates, including Ras-related C3 botulinum toxin substrate 1 (Rac1), nuclear factor erythroid 2-related factor 2 (Nrf2), tumor necrosis factor receptor (TNFR), and optineurin (OPTN), through which participates in several pathophysiological processes, such as oxidative stress, autophagy and inflammation. Therefore, in this review, we elaborately describe the essential substrates of HACE1 and illuminate the pathophysiological processes by which HACE1 is involved in neurodegenerative diseases. We provide a new molecular target for neurodegenerative diseases.


Assuntos
Doenças Neurodegenerativas , Ubiquitina-Proteína Ligases , Humanos , Doença de Alzheimer , Aminoácidos , Doença de Huntington , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Doença de Parkinson , Ubiquitina-Proteína Ligases/antagonistas & inibidores
3.
Science ; 383(6684): eadi3332, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38359126

RESUMO

The identification of mechanisms to store glucose carbon in the form of glycogen rather than fat in hepatocytes has important implications for the prevention of nonalcoholic fatty liver disease (NAFLD) and other chronic metabolic diseases. In this work, we show that glycogenesis uses its intermediate metabolite uridine diphosphate glucose (UDPG) to antagonize lipogenesis, thus steering both mouse and human hepatocytes toward storing glucose carbon as glycogen. The underlying mechanism involves transport of UDPG to the Golgi apparatus, where it binds to site-1 protease (S1P) and inhibits S1P-mediated cleavage of sterol regulatory element-binding proteins (SREBPs), thereby inhibiting lipogenesis in hepatocytes. Consistent with this mechanism, UDPG administration is effective at treating NAFLD in a mouse model and human organoids. These findings indicate a potential opportunity to ameliorate disordered fat metabolism in the liver.


Assuntos
Lipogênese , Glicogênio Hepático , Fígado , Hepatopatia Gordurosa não Alcoólica , Pró-Proteína Convertases , Serina Endopeptidases , Uridina Difosfato Glucose , Animais , Humanos , Camundongos , Carbono/metabolismo , Glucose/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Glicogênio Hepático/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Pró-Proteína Convertases/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Uridina Difosfato Glucose/administração & dosagem , Uridina Difosfato Glucose/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Células HEK293
4.
Food Chem X ; 21: 101159, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38328697

RESUMO

Dioscorea opposita Thumb. cv. Tiegun is commonly consumed as both food and traditional Chinese medicine, which has a history of more than two thousand years. Harvest time directly affects its quality, but few studies have focused on metabolic changes during the harvesting process. Here, a comprehensive metabolomics approach was performed to determine the metabolic profiles during six harvest stages. Thirty eight metabolites with significant differences were determined as crucial participants. Related metabolic pathways including phenylalanine, tyrosine and tryptophan biosynthesis, stilbenoid, diarylheptanoid and gingerol biosynthesis, phenylpropanoid biosynthesis, flavonoid biosynthesis and tryptophan metabolism were the most active pathways during harvest. The results revealed that temperature has a significant impact on quality formation, which suggested that Dioscorea opposita thumb. cv. Tiegun harvested after frost had higher potential value of traditional Chinese medicine. This finding not only offered valuable guidance for yam production, but also provided essential information for assessing its quality.

5.
J Sci Food Agric ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38415792

RESUMO

BACKGROUND: Dioscorea opposita Thunb. cv. Tiegun maturity (DM) is an important factor influencing its quality. However, there are few studies on the impact of harvest time on its maturation. In the present study, a NMR-based metabolomics approach was applied to investigate the dynamic metabolic changes of D. opposita Thunb. cv. Tiegun at six different harvest stages: stage 1 (S1), stage 2 (S2), Stage 3 (S3), stage 4 (S4), stage 5 (S5) and stage 6 (S6). RESULTS: Principal component analysis showed distinct segregation of samples obtained from S1, S2 and S3 compared to those derived from S4, S5 and S6. Interestingly, these samples from the two periods were obtained before and after frost, indicating that frost descent might be important for DM. Eight differential metabolites responsible for good separation of different groups were identified by the principal component analysis loading plot and partial least squares-discriminant analysis. In addition, quantitative analysis of these metabolites using liquid chromatography-tandem mass spectrometry determined the effects of harvest time on these metabolite contents, two of which, sucrose and allantoin, were considered as potential biomarkers to determine DM. CONCLUSION: The present study demonstrated that NMR-based metabolomics approach could serve as a powerful tool to identify differential metabolites during harvesting processes, also offering a fresh insight into understanding the DM and the potential mechanism of quality formation. © 2024 Society of Chemical Industry.

6.
Nat Commun ; 15(1): 1405, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360940

RESUMO

Mechanical force contributes to perforin pore formation at immune synapses, thus facilitating the cytotoxic T lymphocytes (CTL)-mediated killing of tumor cells in a unidirectional fashion. How such mechanical cues affect CTL evasion of perforin-mediated autolysis remains unclear. Here we show that activated CTLs use their softness to evade perforin-mediated autolysis, which, however, is shared by T leukemic cells to evade CTL killing. Downregulation of filamin A is identified to induce softness via ZAP70-mediated YAP Y357 phosphorylation and activation. Despite the requirements of YAP in both cell types for softness induction, CTLs are more resistant to YAP inhibitors than malignant T cells, potentially due to the higher expression of the drug-resistant transporter, MDR1, in CTLs. As a result, moderate inhibition of YAP stiffens malignant T cells but spares CTLs, thus allowing CTLs to cytolyze malignant cells without autolysis. Our findings thus hint a mechanical force-based immunotherapeutic strategy against T cell leukemia.


Assuntos
Citotoxicidade Imunológica , Linfócitos T Citotóxicos , Perforina/genética , Perforina/metabolismo , Proteínas Citotóxicas Formadoras de Poros/genética
7.
Food Chem ; 445: 138756, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38394906

RESUMO

Biomimetic methods are invariably employed to synthesize hybrid organic-inorganic multilevel structure nanoflowers with self-assembly processes in aqueous solutions, which is an ideal way to meet the challenges of immobilizing antibodies or enzymes in nanomaterial based enzyme-linked immunosorbent assay (nano-ELISA). In this study, we developed protein-inorganic hybrid 3D nanoflowers composed of bovine serum albumin (BSA), horseradish peroxidase (HRP)-conjugated goat anti-mouse IgG (IgG-HRP) and copper(Ⅱ) phosphate (BSA-(IgG-HRP)-Cu3(PO4)2) using a self-assembly biomimetic method. The preparation process avoided the use of any organic solvent and protein immobilization did not require covalent modifications. Additionally, the unique hierarchical structure enhances the thermal and storage stability of HRP. The BSA-(IgG-HRP)-Cu3(PO4)2 hybrid 3D nanoflower was then applied to a nano-ELISA platform for pyridaben detection, achieving a 50% inhibition concentration of 3.90 ng mL-1. The nano-ELISA achieved excellent accuracy for pyridaben detection. Such a novel BSA-(IgG-HRP)-Cu3(PO4)2 hybrid 3D nanoflower provide an excellent reagent for small molecule immunoassay.


Assuntos
Cobre , Nanoestruturas , Piridazinas , Cobre/química , Nanoestruturas/química , Peroxidase do Rábano Silvestre/química , Ensaio de Imunoadsorção Enzimática , Soroalbumina Bovina
8.
Nat Immunol ; 25(3): 552-561, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38263463

RESUMO

The steady flow of lactic acid (LA) from tumor cells to the extracellular space via the monocarboxylate transporter symport system suppresses antitumor T cell immunity. However, LA is a natural energy metabolite that can be oxidized in the mitochondria and could potentially stimulate T cells. Here we show that the lactate-lowering mood stabilizer lithium carbonate (LC) can inhibit LA-mediated CD8+ T cell immunosuppression. Cytoplasmic LA increased the pumping of protons into lysosomes. LC interfered with vacuolar ATPase to block lysosomal acidification and rescue lysosomal diacylglycerol-PKCθ signaling to facilitate monocarboxylate transporter 1 localization to mitochondrial membranes, thus transporting LA into the mitochondria as an energy source for CD8+ T cells. These findings indicate that targeting LA metabolism using LC could support cancer immunotherapy.


Assuntos
Antimaníacos , Ácido Láctico , Carbonato de Lítio , Mitocôndrias , Neoplasias , Humanos , Linfócitos T CD8-Positivos , Ácido Láctico/metabolismo , Carbonato de Lítio/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Antimaníacos/farmacologia
9.
Pathol Res Pract ; 254: 155151, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38290402

RESUMO

Gastric cancer remains a highly prevalent malignancy worldwide with its molecular features poorly understood. To gain full insight into its genetic landscape, we performed whole-transcriptome sequencing on human tumors and adjacent non-tumors to predict the function of microRNA, long coding RNA, circular RNA, and mRNA, as well as estimate their correlation with gastric cancer characteristics through construction of ceRNA, WGCNA and PPI network. Functional enrichment analysis annotated nucleic acid binding, enzyme activity and binding related to differentially expressed miRNAs (dif-miRNAs); energy binding and enzyme binding related to dif-lncRNAs; protein binding and enzyme activity related to dif-circRNAs; protein digestion and absorption related to dif-mRNAs. The expression of key miR-135a-5p, lncRNAs-MSTRG.48856.1, ENST00000569981, MSTRG.22826.1, ENST00000564492, circRNAs-CCSER2, FNDC3B, CORO1C, FAM214A were validated by real-time PCR. The ceRNA network filtered 14 miRNAs, 30 lncRNAs, and 6 mRNA in the lncRNA-ceRNA axis and 8 miRNAs, 9 circRNAs, and 3 mRNA in the circRNA-ceRNA axis. Genes involved in ceRNA were annotated to be closely related to tumor material synthesis and metabolism. The WGCNA network filtered gene clusters related to TNM traits and extracted the hub genes CLDN10, CD177, newGene_35523, newGene_51201, CEACAM7, and newGene_46634. These genes were associated with cell proliferation, metabolism, and enzyme activity regulation. The PPI network analyzed the stable interaction relationships of the hub genes. Our research provides a valuable resource for understanding the molecular mechanisms of gastric cancer from the perspective of tumor metabolism.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Humanos , MicroRNAs/genética , RNA Circular/genética , Neoplasias Gástricas/genética , RNA Longo não Codificante/genética , Biologia Computacional , RNA Mensageiro , Redes Reguladoras de Genes
10.
Bioresour Technol ; 394: 130210, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38113949

RESUMO

Electrochemical sludge pretreatment is receiving increasing attention because of its small footprint and higher environmental compatibility. However, the limited effective area of electrode plates and the low conductivity of sludge hinder the widespread application of electrochemical pretreatment. In this study, granular activated carbon (GAC) was employed to construct a fluidized electrode electrochemical system (FEE) to promote electrochemical pretreatment. Under the optimal operating parameters, the FEE system could effectively facilitate sludge decomposition, indicated by 126% increase in soluble chemical oxygen demand (SCOD) and 23.1% reduction in sludge volume. Mechanism study revealed that the addition of GAC significantly enhanced the conductivity of sludge, thereby promoting the oxidation capacity of FEE system. Furthermore, continuously generated H2O2 in FEE further promoted sludge solubilization. GAC offered an effectively, green and sustainable enhancement approach for sludge electrochemical pretreatment.


Assuntos
Carvão Vegetal , Esgotos , Peróxido de Hidrogênio , Reatores Biológicos , Eletrodos
11.
J Clin Invest ; 133(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099490

RESUMO

Elevation of reactive oxygen species (ROS) levels is a general consequence of tumor cells' response to treatment and may cause tumor cell death. Mechanisms by which tumor cells clear fatal ROS, thereby rescuing redox balance and entering a chemoresistant state, remain unclear. Here, we show that cysteine sulfenylation by ROS confers on aryl hydrocarbon receptor (AHR) the ability to dissociate from the heat shock protein 90 complex but to bind to the PPP1R3 family member PPP1R3C of the glycogen complex in drug-treated tumor cells, thus activating glycogen phosphorylase to initiate glycogenolysis and the subsequent pentose phosphate pathway, leading to NADPH production for ROS clearance and chemoresistance formation. We found that basic ROS levels were higher in chemoresistant cells than in chemosensitive cells, guaranteeing the rapid induction of AHR sulfenylation for the clearance of excess ROS. These findings reveal that AHR can act as an ROS sensor to mediate chemoresistance, thus providing a potential strategy to reverse chemoresistance in patients with cancer.


Assuntos
Glicogenólise , Neoplasias , Humanos , Espécies Reativas de Oxigênio/metabolismo , Resistencia a Medicamentos Antineoplásicos , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética
12.
Heliyon ; 9(10): e20804, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37928388

RESUMO

Background: Gastric cancer (GC) is a prevalent malignancy of the digestive tract globally, demonstrating a substantial occurrence of relapse and metastasis, alongside the absence of efficacious treatment. Tumor progression and the development of cancer are linked to oxidative stress. Our objective was twofold: first, to determine distinct subcategories based on oxidative stress in GC patients, and second, to establish oxidative stress-related genes that would aid in stratifying the risk for GC patients. Methods: TCGA-STAD and GSE84437 datasets were utilized to obtain the mRNA expression profiles and corresponding clinical information of GC patients. Through consensus clustering analysis, distinct subgroups related to oxidative stress were identified. To uncover the underlying mechanisms, GSEA and GSVA were performed. xCell, CIBERSORT, MCPCounter, and TIMER algorithms were employed to evaluate the immune microenvironment and immune status of the different GC subtypes. A prognostic risk model was developed using the TCGA-STAD dataset and substantiated using the GSE84437 dataset. Furthermore, qRT-PCR was employed to validate the expression of genes associated with prognosis. Results: Two distinct subtypes of oxidative stress were discovered, with markedly different survival rates. The C1 subtype demonstrated an activated immune signal pathway, a significant presence of immune cell infiltration, high immune score, and a high microenvironment score, indicating a poor prognosis. Moreover, a prognostic signature related to oxidative stress (IMPACT and PXDN) was able to accurately estimate the likelihood of survival for patients with gastric cancer. A nomogram incorporating the patients' gender, age, and risk score was able to predict survival in gastric cancer patients. Additionally, the expression of IMPACT and PXDN showed a strong correlation with overall survival and the infiltration of immune cells. Conclusion: Based on signatures related to oxidative stress, we developed an innovative system for categorizing patients with GC. This stratification enables accurate prognostication of individuals with GC.

13.
Nat Immunol ; 24(12): 2042-2052, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37919525

RESUMO

Tumor-derived factors are thought to regulate thrombocytosis and erythrocytopenia in individuals with cancer; however, such factors have not yet been identified. Here we show that tumor cell-released kynurenine (Kyn) biases megakaryocytic-erythroid progenitor cell (MEP) differentiation into megakaryocytes in individuals with cancer by activating the aryl hydrocarbon receptor-Runt-related transcription factor 1 (AhR-RUNX1) axis. During tumor growth, large amounts of Kyn from tumor cells are released into the periphery, where they are taken up by MEPs via the transporter SLC7A8. In the cytosol, Kyn binds to and activates AhR, leading to its translocation into the nucleus where AhR transactivates RUNX1, thus regulating MEP differentiation into megakaryocytes. In addition, activated AhR upregulates SLC7A8 in MEPs to induce positive feedback. Importantly, Kyn-AhR-RUNX1-regulated MEP differentiation was demonstrated in both humanized mice and individuals with cancer, providing potential strategies for the prevention of thrombocytosis and erythrocytopenia.


Assuntos
Neoplasias , Trombocitose , Animais , Camundongos , Cinurenina/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Megacariócitos/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Células Precursoras Eritroides/metabolismo , Diferenciação Celular/fisiologia , Neoplasias/metabolismo , Trombocitose/metabolismo , Viés
15.
J Environ Manage ; 348: 119286, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37857216

RESUMO

Medium chain fatty acids (MCFAs), the secondary products of traditional anaerobic fermentation, can be produced via chain elongation (CE), a process often retarded due to the difficulty during interspecies electron transfer (IET). This study employed redox mediators, neutral red (NR), methyl viologen (MV), and methylene blue (MB) as electron shuttles to expedite the electro-fermentation for caproate production by improving IET. Results showed that MV increased the MCFAs production by promoting acetate to ethanol conversion, leading to the highest MCFAs selectivity of 68.73%. While NR was indicated to improve CE by encouraging H2 production, and the biocathode had the highest electrical activity due to the smallest internal resistance and largest capacitance increase of 96% than the control. A higher proportion of Sutterella, Prevotella, and Hydrogenophaga, linked with the H2 mediated interspecies electron transfer (MIET) during CE process, was observed across redox mediators supplied groups compared to the control. The presence of mediators led to an elevated abundance of key enzymes for enhanced CE process and electron transfer. This study provided the perspective of the stimulated electron transfer for improved MCFAs production in electro-fermentation systems.


Assuntos
Caproatos , Ácidos Graxos , Fermentação , Oxirredução
16.
Environ Res ; 236(Pt 2): 116822, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37541415

RESUMO

The new anaerobic/oxic/anoxic-aerobic granular sludge (AOA-AGS) merits the advantages of effective carbon utilization and low-carbon treatment. However, low temperature poses stressing concerns and the resisting mechanism remains much unknown. Herein, an AOA-AGS process was configured for simultaneous nitrification, denitrification and phosphorus removal (SNDPR) with low-strength wastewater from ambient (>15 °C) to winter temperatures (<15 °C). Results showed that simultaneously advanced nutrients removal, and dramatic in situ sludge reduction (Yobs of 0.093 g MLSS/g COD) were gained regardless of seasonally decreasing temperatures. Winter temperatures even amplified Candidatus Competibacter predominating from 20.11% to 34.74%, which laid the core basis for endogenous denitrification, sludge minimization and temperature resistance. A removal model was thus proposed given the observed functional groups, and doubts were also raised for future investigations. This study would aid a better understanding on the microbial ecology and engineering aspects of the new AOA-AGS process treating low-strength wastewater at low temperatures.

18.
Bioresour Technol ; 386: 129574, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37506946

RESUMO

Modern paradigm has upgraded wastewater treatment plants (WWTPs) to water resources recovery facilities (WRRFs), where aerobic granular sludge (AGS) is a sewage treatment technology with promising phosphorus recovery (PR) potential. Herein, the AGS-based simultaneous nitrification, denitrification, and phosphorus removal coupling side-stream PR process (AGS-SNDPRr) was developed with municipal wastewater. Results revealed that AGS always maintained good structural stability, and pollutant removal was unaffected and effective after 40 days of anaerobic phosphorus-rich liquid extraction (fixed rate of 30%). The AGS-SNDPRr achieved a stable phosphorus recovery efficiency of 63.40%, and the side-stream PR further exaggerated in situ sludge reduction by 7.7-10%. Apart from responses of extracellular polymeric substances (EPS), the Matthew effect of typical denitrifying glycogen accumulating organisms (DGAOs) Candidatus_Competibacter up to 67.40% mainly contributed to enhanced performance of this new process. This study demonstrated a new approach for simultaneous advanced wastewater treatment, phosphorus recovery, and excess sludge minimization.


Assuntos
Esgotos , Purificação da Água , Desnitrificação , Eliminação de Resíduos Líquidos/métodos , Fósforo , Rios , Reatores Biológicos , Nitrificação , Nitrogênio/análise
19.
Cells ; 12(10)2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37408231

RESUMO

Melatonin (N-acetyl-5-methoxytryptamine) plays an important role in plant growth and development, and in the response to various abiotic stresses. However, its role in the responses of barley to low phosphorus (LP) stress remains largely unknown. In the present study, we investigated the root phenotypes and metabolic patterns of LP-tolerant (GN121) and LP-sensitive (GN42) barley genotypes under normal P, LP, and LP with exogenous melatonin (30 µM) conditions. We found that melatonin improved barley tolerance to LP mainly by increasing root length. Untargeted metabolomic analysis showed that metabolites such as carboxylic acids and derivatives, fatty acyls, organooxygen compounds, benzene and substituted derivatives were involved in the LP stress response of barley roots, while melatonin mainly regulated indoles and derivatives, organooxygen compounds, and glycerophospholipids to alleviate LP stress. Interestingly, exogenous melatonin showed different metabolic patterns in different genotypes of barley in response to LP stress. In GN42, exogenous melatonin mainly promotes hormone-mediated root growth and increases antioxidant capacity to cope with LP damage, while in GN121, it mainly promotes the P remobilization to supplement phosphate in roots. Our study revealed the protective mechanisms of exogenous MT in alleviating LP stress of different genotypes of barley, which can be used in the production of phosphorus-deficient crops.


Assuntos
Hordeum , Melatonina , Fósforo , Raízes de Plantas , Estresse Fisiológico , Melatonina/farmacologia , Melatonina/fisiologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Fósforo/deficiência , Hordeum/efeitos dos fármacos , Hordeum/genética , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Genótipo , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
20.
Comput Biol Med ; 164: 107212, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37478712

RESUMO

The Sine Cosine Algorithm (SCA) is an outstanding optimizer that is appreciably used to dissolve complicated real-world problems. Nevertheless, this algorithm lacks sufficient population diversification and a sufficient balance between exploration and exploitation. So, effective techniques are required to tackle the SCA's fundamental shortcomings. Accordingly, the present paper suggests an improved version of SCA called Hierarchical Multi-Leadership SCA (HMLSCA) which uses an effective hierarchical multi-leadership search mechanism to lead the search process on multiple paths. The efficiency of the HMLSCA has been appraised and compared with a set of famous metaheuristic algorithms to dissolve the classical eighteen benchmark functions and thirty CEC 2017 test suites. The results demonstrate that the HMLSCA outperforms all compared algorithms and that the proposed algorithm provided a promising efficiency. Moreover, the HMLSCA was applied to handle the medicine data classification by optimizing the support vector machine's (SVM) parameters and feature weighting in eight datasets. The experiential outcomes verify the productivity of the HMLSCA with the highest classification accuracy and a gain scoring 1.00 Friedman mean rank versus the other evaluated metaheuristic algorithms. Furthermore, the proposed algorithm was used to diagnose COVID-19, in which it attained the topmost accuracy of 98% in diagnosing the infection on the COVID-19 dataset, which proves the performance of the proposed search strategy.


Assuntos
COVID-19 , Medicina , Humanos , Liderança , Algoritmos , Benchmarking
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