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The development of a vaccine specific to severe acute respiratory syndrome coronavirus 2 Omicron has been hampered due to its low immunogenicity. Here, using reverse mutagenesis, we found that a phenylalanine-to-serine mutation at position 375 (F375S) in the spike protein of Omicron to revert it to the sequence found in Delta and other ancestral strains significantly enhanced the immunogenicity of Omicron vaccines. Sequence FAPFFAF at position 371-377 in Omicron spike had a potent inhibitory effect on macrophage uptake of receptor-binding domain (RBD) nanoparticles or spike-pseudovirus particles containing this sequence. Omicron RBD enhanced binding to Siglec-9 on macrophages to impair phagocytosis and antigen presentation and promote immune evasion, which could be abrogated by the F375S mutation. A bivalent F375S Omicron RBD and Delta-RBD nanoparticle vaccine elicited potent and broad nAbs in mice, rabbits and rhesus macaques. Our research suggested that manipulation of the Siglec-9 pathway could be a promising approach to enhance vaccine response.
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COVID-19 , SARS-CoV-2 , Animais , Camundongos , Coelhos , Anticorpos Neutralizantes , Anticorpos Antivirais , Macaca mulatta , Macrófagos , Nanovacinas , Fagocitose , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido SiálicoRESUMO
Previous observational and experimental studies have suggested a relationship between statin treatments and the augmentation of immunotherapy effects; however, the causal role of statin usage in promoting antitumor immunity remains largely unexplored. Utilizing large-scale genome-wide association studies, we conducted a Mendelian Randomization (MR) analysis to examine the association between genetically proxied inhibition of the gene for 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), a specific target of statins, and 524 immunotherapy-related profiles, encompassing immune cells, inflammatory cytokines, immune checkpoints, and gut microbiota. Our findings indicated a suggestive association between statin therapy and proinflammatory as well as antitumor effects; notably, inhibition of HMGCR demonstrated a robust link with increased susceptibility of various immune cell types, including basophil cells, white blood cells, eosinophil cells, neutrophil cells, activated CD8+ T cells, dendritic cells, and natural killer cells; furthermore, a causal relationship was observed between statin use and a decrease in terminal CD8+ T cells, granulocytes, monocytes, and myeloid-derived suppressor cells; genetically proxied statin usage was also significantly associated with elevated levels of proinflammatory cytokines and immunotherapy-related gut microbiota; importantly, the potential inhibition of HMGCR in influencing the response to immunotherapy was confirmed in the real-world cohorts. This study provides novel insights into the regulatory role of HMGCR inhibition in antitumor immunity, suggesting that strategies targeting HMGCR or lipid regulation may hold therapeutic potential for enhancing the efficacy of immunotherapy.
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Imunoterapia , Metabolismo dos Lipídeos , Análise da Randomização Mendeliana , Humanos , Imunoterapia/métodos , Metabolismo dos Lipídeos/genética , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Estudo de Associação Genômica Ampla , Inflamação/imunologia , Hidroximetilglutaril-CoA Redutases/imunologia , Hidroximetilglutaril-CoA Redutases/genética , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/genéticaRESUMO
Immunity imbalance of T helper 17 (Th17)/regulatory T (Treg) cells is involved in the pathogenesis of Crohn's disease (CD). Complanatuside A (CA), a flavonol glycoside, exerts anti-inflammatory activities and our study aimed to identify its effect on TNBS-induced colitis and the possible mechanisms. We found that CA alleviated the symptoms of colitis in TNBS mice, as demonstrated by prevented weight loss and colon length shortening, as well as decreased disease activity index scores, inflammatory scores, and levels of proinflammatory factors. Flow cytometry analysis showed that CA markedly reduced the percentage of Th17 cells while increasing the percentage of Treg cells in TNBS mice. Under Th17 cell polarizing conditions, CA inhibited the differentiation of Th17 cells while the Treg cell differentiation was elevated under Treg cell polarizing conditions. Furthermore, it was observed that JAK2 interacted with CA through six hydrogen bonds via molecular docking. The phosphorylation of JAK2/STAT3 was reduced by CA, which might be correlated with the protective effect of CA on colitis. In conclusion, CA reduced the imbalance of Th17/Treg cells by inhibiting the JAK2/STAT3 signaling pathway in TNBS-induced colitis, which may provide novel strategies for CD treatment.
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Colite , Janus Quinase 2 , Fator de Transcrição STAT3 , Transdução de Sinais , Linfócitos T Reguladores , Células Th17 , Animais , Masculino , Camundongos , Diferenciação Celular/efeitos dos fármacos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Janus Quinase 2/metabolismo , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/metabolismo , Ácido TrinitrobenzenossulfônicoRESUMO
The NLR family pyrin domain containing 3 (NLRP3) inflammasome plays an important role in the pathogenesis of a wide variety of human diseases. So far, drugs directly and specifically targeting the NLRP3 inflammasome are not available for clinical use since the safety and efficacy of new compounds are often unclear. A promising approach is thus to identify NLRP3 inhibitors from existing drugs that are already in clinical use. Here, we show that mefloquine, a well-known antimalarial drug, is a highly selective and potent NLRP3 inhibitor by screening a FDA-approved drug library. Mechanistically, mefloquine directly binds to the NLRP3 NACHT and LRR domains to prevent NLRP3 inflammasome activation. More importantly, mefloquine treatment attenuates the symptoms of lipopolysaccharide-induced systemic inflammation and Parkinson's disease-like neural damage in mice. Our findings identify mefloquine as a potential therapeutic agent for NLRP3-driven diseases and migth expand its clinical use considerably.
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Self-related information is crucial in our daily lives, which has led to the proposal that there is a specific brain mechanism for processing it. Neuroimaging studies have consistently demonstrated that the default mode network (DMN) is strongly associated with the representation and processing of self-related information. However, the precise relationship between DMN activity and self-related information, particularly in terms of neural oscillations, remains largely unknown. We electrically stimulated the superior temporal and fusiform areas, using stereo-electroencephalography to investigate neural oscillations associated with elicited self-related auditory hallucinations. Twenty-two instances of auditory hallucinations were recorded and categorized into self-related and other-related conditions. Comparing oscillatory power changes within the DMN between self-related and other-related auditory hallucinations, we discovered that self-related hallucinations are associated with significantly stronger positive power changes in both alpha and gamma bands compared to other-related hallucinations. To ensure the validity of our findings, we conducted controlled analyses for factors of familiarity and clarity, which revealed that the observed effects within the DMN remain independent of these factors. These results underscore the significance of the functional role of the DMN during the processing of self-related auditory hallucinations and shed light on the relationship between self-related perception and neural oscillatory activity.
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Esquizofrenia , Humanos , Rede de Modo Padrão , Alucinações/complicações , Encéfalo , Estimulação Elétrica , Imageamento por Ressonância Magnética/métodosRESUMO
Controllable large-scale integration of two-dimensional (2D) materials with organic semiconductors and the realization of strong coupling between them still remain challenging. Herein, we demonstrate a wafer-scale, vertically layered SnSe2/PTAA heterojunction array with high light-trapping ability via a low-temperature molecular beam epitaxy method and a facile spin-coating process. Conductive probe atomic force microscopy (CP-AFM) measurements reveal strong rectification and photoresponse behavior in the individual SnSe2 nanosheet/PTAA heterojunction. Theoretical analysis demonstrates that vertically layered SnSe2/PTAA heterojunctions exhibit stronger C-Se covalent coupling than that of the conventional tiled type, which could facilitate more efficient charge transfer. Benefiting from these advantages, the SnSe2/PTAA heterojunction photodetectors with an optimized PTAA concentration show high performance, including a responsivity of 41.02 A/W, an external quantum efficiency of 1.31 × 104%, and high uniformity. The proposed approach for constructing large-scale 2D inorganic-organic heterostructures represents an effective route to fabricate high-performance broadband photodetectors for integrated optoelectronic systems.
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Propane dehydrogenation (PDH) serves as a pivotal intentional technique to produce propylene. The stability of PDH catalysts is generally restricted by the readsorption of propylene which can subsequently undergo side reactions for coke formation. Herein, we demonstrate an ultrastable PDH catalyst by encapsulating PtIn clusters within silicalite-1 which serves as an efficient promoter for olefin desorption. The mean lifetime of PtIn@S-1 (S-1, silicalite-1) was calculated as 37317 h with high propylene selectivity of >97% at 580 °C with a weight hourly space velocity (WHSV) of 4.7 h-1. With an ultrahigh WHSV of 1128 h-1, which pushed the catalyst away from the equilibrium conversion to 13.3%, PtIn@S-1 substantially outperformed other reported PDH catalysts in terms of mean lifetime (32058 h), reaction rates (3.42 molpropylene gcat-1 h-1 and 341.90 molpropylene gPt-1 h-1), and total turnover number (14387.30 kgpropylene gcat-1). The developed catalyst is likely to lead the way to scalable PDH applications.
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BACKGROUND: Frailty is associated with an increased risk of all-cause death and cardiovascular events. However, it is uncertain whether frailty modifies the efficacy and safety of intensive blood pressure control. METHODS: Data from SPRINT (Systolic Blood Pressure Intervention Trial) were used to construct a frailty index. Subgroup differences in intensive blood pressure control treatment effects and safety outcomes were measured on a relative and an absolute scale in patients with and without frailty (defined as a frailty index >0.21) using Cox proportional hazard models and generalized linear models, respectively. The primary outcome was a composite of myocardial infarction, acute coronary syndrome without myocardial infarction, stroke, heart failure, and cardiovascular death. RESULTS: A total of 9306 patients (mean age, 67.9±9.4 years), 2560 (26.7%) of whom had frailty, were included in our study. Over a median follow-up of 3.22 years, 561 primary outcomes were observed. Patients with frailty had a significantly higher risk of primary outcome in both the intensive and standard blood pressure control arms (adjusted hazard ratio, 2.10 [95% CI, 1.59-2.77] and 1.85 [95% CI, 1.46-2.35], respectively). Intensive treatment effects on primary and secondary outcomes were not significantly different on a relative scale (except for cardiovascular death [hazard ratio in patients with and without frailty, 0.91 (95% CI, 0.52-1.60) versus 0.30 (95% CI, 0.16-0.59), respectively; Pinteraction=0.01]) or absolute scale. There was no significant interaction between frailty and risks for serious adverse events with intensive treatment. CONCLUSIONS: Frailty status was a marker of high cardiovascular risk. Patients with frailty benefit similarly to other patients from intensive blood pressure control without an increased risk of serious adverse events.
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Fragilidade , Hipertensão , Infarto do Miocárdio , Idoso , Humanos , Pessoa de Meia-Idade , Anti-Hipertensivos/efeitos adversos , Pressão Sanguínea , Fragilidade/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/complicações , Infarto do Miocárdio/tratamento farmacológico , Fatores de Risco , Resultado do TratamentoRESUMO
Diabetic nephropathy (DN) is a serious public health problem worldwide, and ferroptosis is deeply involved in the pathogenesis of DN. Prediabetes is a critical period in the prevention and control of diabetes and its complications, in which kidney injury occurs. This study aimed to explore whether ferroptosis would induce kidney injury in prediabetic mice, and whether vitamin D (VD) supplementation is capable of preventing kidney injury by inhibiting ferroptosis, while discussing the potential mechanisms. High-fat diet (HFD) fed KKAy mice and high glucose (HG) treated HK-2 cells were used as experimental subjects in the current study. Our results revealed that serious injury and ferroptosis take place in the kidney tissue of prediabetic mice; furthermore, VD intervention significantly improved the kidney structure and function in prediabetic mice and inhibited ferroptosis, showing ameliorated iron deposition, enhanced antioxidant capability, reduced reactive oxygen species (ROS) and lipid peroxidation accumulation. Meanwhile, VD up-regulated Klotho, solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) expression, and down-regulated p53, transferrin receptor 1 (TFR1) and Acyl-Coenzyme A synthetase long-chain family member 4 (ACSL4) expression. Moreover, we demonstrated that HG-induced ferroptosis is antagonized by treatment of VD and knockdown of Klotho attenuates the protective effect of VD on ferroptosis in vitro. In conclusion, ferroptosis occurs in the kidney of prediabetic mice and VD owns a protective effect on prediabetic kidney injury, possibly by via the Klotho/p53 pathway, thus inhibiting hyperglycemia-induced ferroptosis.
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BACKGROUND: Intestinal inflammation and compromised barrier function are critical factors in the pathogenesis of gastrointestinal disorders. This study aimed to investigate the role of miR-192-5p in modulating intestinal epithelial barrier (IEB) integrity and its association with autophagy. METHODS: A DSS-induced colitis model was used to assess the effects of miR-192-5p on intestinal inflammation. In vitro experiments involved cell culture and transient transfection techniques. Various assays, including dual-luciferase reporter gene assays, quantitative real-time PCR, western blotting, and measurements of transepithelial electrical resistance, were performed to evaluate changes in miR-192-5p expression, Rictor levels, and autophagy flux. Immunofluorescence staining, H&E staining, TEER measurements, and FITC-dextran analysis were also employed. RESULTS: Our findings revealed a reduced expression of miR-192-5p in inflamed intestinal tissues, correlating with impaired IEB function. Overexpression of miR-192-5p alleviated TNF-induced IEB dysfunction by targeting Rictor, resulting in enhanced autophagy flux in enterocytes (ECs). Moreover, the therapeutic potential of miR-192-5p was substantiated in colitis mice, wherein increased miR-192-5p expression ameliorated intestinal inflammatory injury by enhancing autophagy flux in ECs through the modulation of Rictor. CONCLUSION: Our study highlights the therapeutic potential of miR-192-5p in enteritis by demonstrating its role in regulating autophagy and preserving IEB function. Targeting the miR-192-5p/Rictor axis is a promising approach for mitigating gut inflammatory injury and improving barrier integrity in enteritis patients.
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Fungicides have been widely used to protect crops from the disease of pythium aphanidermatum (PA). However, excessive use of synthetic fungicides can lead to fungal pathogens developing microbicide resistance. Recently, biomimetic nano-delivery systems have been used for controlled release, reducing the overuse of fungicides, and thereby protecting the environment. In this paper, inspired by chloroplast membranes, visible light biomimetic channels are constructed by using retinal, the main component of green pigment on chloroplasts in plants, which can achieve the precise controlled release of the model fungicide methylene blue (MB). The experimental results show that the biomimetic channels have good circularity after and before light conditions. In addition, it is also found that the release of MB in visible light by the retinal-modified channels is 8.78 µmol·m-2·h-1, which is four times higher than that in the before light conditions. Furthermore, MB, a bactericide drug model released under visible light, can effectively inhibit the growth of PA, reaching a 97% inhibition effect. The biomimetic nanochannels can realize the controlled release of the fungicide MB, which provides a new way for the treatment of PA on the leaves surface of cucumber, further expanding the application field of biomimetic nanomembrane carrier materials.
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Covalent organic frameworks (COFs) are promising porous materials due to their high specific surface area, adjustable structure, highly ordered nanochannels, and abundant functional groups, which brings about wide applications in the field of gas adsorption, hydrogen storage, optics, and so forth. In recent years, COFs have attracted considerable attention in electrochemical energy storage and conversion. Specifically, COF-based functional separators are ideal candidates for addressing the ionic transport-related issues in high-energy batteries, such as dendritic formation and shuttle effect. Therefore, it is necessary to make a comprehensive understanding of the mechanism of COFs in functional separators. In this review, the advantages, applications as well as synthesis of COFs are firstly presented. Then, the mechanism of COFs in functional separators for high-energy batteries is summarized in detail, including pore channels regulating ionic transport, functional groups regulating ionic transport, adsorption effect, and catalytic effect. Finally, the application prospect of COFs-based separators in high-energy batteries is proposed. This review may provide new insights into the design of functional separators for advanced electrochemical energy storage and conversion systems.
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OBJECTIVES: The emergence and expansion of carbapenem-resistant Klebsiella pneumoniae infections is a concern due to the lack of 'first-line' antibiotic treatment options. The ceftazidime/avibactam is an important clinical treatment for carbapenem-resistant K. pneumoniae infections but there is an increasing number of cases of treatment failure and drug resistance. Therefore, a potential solution is combination therapies that result in synergistic activity against K. pneumoniae carbapenemase: producing K. pneumoniae (KPC-Kp) isolates and preventing the emergence of KPC mutants resistant to ceftazidime/avibactam are needed in lieu of novel antibiotics. METHODS: To evaluate their synergistic activity, antibiotic combinations were tested against 26 KPC-Kp strains. Antibiotic resistance profiles, molecular characteristics and virulence genes were investigated by susceptibility testing and whole-genome sequencing. Antibiotic synergy was evaluated by in vitro chequerboard experiments, time-killing curves and dose-response assays. The mouse thigh model was used to confirm antibiotic combination activities in vivo. Additionally, antibiotic combinations were evaluated for their ability to prevent the emergence of ceftazidime/avibactam resistant mutations of blaKPC. RESULTS: The combination of ceftazidime/avibactam plus meropenem showed remarkable synergistic activity against 26 strains and restored susceptibility to both the partnering antibiotics. The significant therapeutic effect of ceftazidime/avibactam combined with meropenem was also confirmed in the mouse model and bacterial loads in the thigh muscle of the combination groups were significantly reduced. Furthermore, ceftazidime/avibactam plus meropenem showed significant activity in preventing the occurrence of resistance mutations. CONCLUSIONS: Our results indicated that the combination of ceftazidime/avibactam plus meropenem offers viable therapeutic alternatives in treating serious infections due to KPC-Kp.
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Antibacterianos , Compostos Azabicíclicos , Proteínas de Bactérias , Ceftazidima , Modelos Animais de Doenças , Combinação de Medicamentos , Sinergismo Farmacológico , Infecções por Klebsiella , Klebsiella pneumoniae , Meropeném , Testes de Sensibilidade Microbiana , beta-Lactamases , Animais , Ceftazidima/farmacologia , Ceftazidima/uso terapêutico , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Compostos Azabicíclicos/farmacologia , Compostos Azabicíclicos/uso terapêutico , Meropeném/farmacologia , Meropeném/administração & dosagem , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos , beta-Lactamases/genética , Proteínas de Bactérias/genética , Feminino , Sequenciamento Completo do Genoma , Quimioterapia Combinada , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genéticaRESUMO
Understanding the molecular regulation of plant response to drought is the basis of drought-resistance improvement through molecular strategies. Here, we characterized apple (Malus × domestica) histone deacetylase 6 (MdHDA6), which negatively regulates apple drought tolerance by catalyzing deacetylation on histones associated with drought-responsive genes. Transgenic apple plants over-expressing MdHDA6 were less drought-tolerant, while those with down-regulated MdHDA6 expression were more drought-resistant than nontransgenic apple plants. Transcriptomic and histone 3 acetylation (H3ac) Chromatin immunoprecipitation-seq analyses indicated that MdHDA6 could facilitate histone deacetylation on the drought-responsive genes, repressing gene expression. Moreover, MdHDA6 interacted with the abscisic acid (ABA) signaling transcriptional factor, ABSCISIC ACID-INSENSITIVE 5 (MdABI5), forming the MdHDA6-MdABI5 complex. Interestingly, MdHDA6 facilitated histone deacetylation on the drought-responsive genes regulated by MdABI5, resulting in gene repression. Furthermore, a dual-Luc experiment showed that MdHDA6 could repress the regulation of a drought-responsive gene, RESPONSIVE TO DESICCATION 29A (MdRD29A) activated by MdABI5. On the one hand, MdHDA6 can facilitate histone deacetylation and gene repression on the positive drought-responsive genes to negatively regulate drought tolerance in apple. On the other hand, MdHDA6 directly interacts with MdABI5 and represses the expression of genes downstream of MdABI5 via histone deacetylation around these genes to reduce drought tolerance. Our study uncovers a different drought response regulatory mechanism in apple based on the MdHDA6-MdABI5 complex function and provides the molecular basis for drought-resistance improvement in apple.
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Malus , Proteínas de Plantas , Ácido Abscísico/metabolismo , Resistência à Seca , Secas , Regulação da Expressão Gênica de Plantas , Desacetilase 6 de Histona/genética , Histonas/genética , Histonas/metabolismo , Malus/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genéticaRESUMO
MET exon 14 skipping alterations and MET amplifications are recognized as oncogenic and targetable genetic changes in cancer patients. The treatment of MET-selective tyrosine kinase inhibitors (TKIs) in this specific population has shown encouraging therapeutic results. However, a comprehensive understanding of the potential toxicities linked to these agents is still lacking. The present pharmacovigilance analysis was carried out using the FDA Adverse Event Reporting System database to assess notable adverse events associated with MET-selective TKIs. Gastrointestinal disorders, respiratory toxicity, hepatotoxicity, and disturbances in metabolism and nutrition demonstrated a substantial prevalence and significance among the adverse event (AE) categories. Particularly notable were the occurrences of peripheral oedema, nausea, dysphagia, fatigue, and dyspnoea, which emerged as the foremost five reported AEs. The majority of these AEs were observed within the initial months of initiating treatment with MET-selective TKIs and persistently thereafter. Notably, our investigation unveiled a significant correlation between the usage of capmatinib and the incidence of hearing loss and difficulty in swallowing. Diligent monitoring and the implementation of supportive care strategies are essential in managing the toxicities associated with MET-selective TKIs, particularly those related to gastrointestinal disorders, respiratory toxicity, hepatotoxicity, and ototoxicity.
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Farmacovigilância , Proteínas Proto-Oncogênicas c-met , Humanos , Sistemas de Notificação de Reações Adversas a Medicamentos , Antineoplásicos/efeitos adversos , Benzamidas/efeitos adversos , Imidazóis , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Triazinas/efeitos adversos , /efeitos adversosRESUMO
Ethylene-responsive factors (ERF) play an important role in plant responses to waterlogging stress. However, the function and mechanism of action of ERFVIII in response to waterlogging stress remain poorly understood. In this study, we found that expression of the ERF VIIIa gene CmERF4 in chrysanthemum was induced by waterlogging stress. CmERF4 localized to the nucleus when expressed in tobacco leaves. Yeast two-hybrid and luciferase assays showed that CmERF4 is a transcriptional inhibitor. CmERF4 overexpression in chrysanthemum reduced plant waterlogging tolerance, whereas overexpression of the chimeric activator CmERF4-VP64 reversed its transcriptional activity, promoting higher waterlogging tolerance than that observed in wild-type plants, indicating that CmERF4 negatively regulates waterlogging tolerance. Transcriptome profiling showed that energy metabolism and reactive oxygen species (ROS) pathway-associated genes were differentially expressed between CmERF4-VP64 and wild-type plants. RT-qPCR analysis of selected energy metabolism and reactive oxygen species-related genes showed that the gene expression patterns were consistent with the expression levels obtained from RNA-seq analysis. Overall, we identified new functions of CmERF4 in negatively regulating chrysanthemum waterlogging tolerance by modulating energy metabolism and ROS pathway genes.
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Chrysanthemum , Espécies Reativas de Oxigênio/metabolismo , Chrysanthemum/genética , Chrysanthemum/metabolismo , Regulação da Expressão Gênica de Plantas , Etilenos/metabolismo , Estresse Fisiológico/genéticaRESUMO
Trichomes, specialized hair-like structures in the epidermal cells of the aboveground parts of plants, protect plants from pests and pathogens and produce valuable metabolites. Chrysanthemum morifolium, used in tea products, has ornamental and medicinal value. However, it is susceptible to Alternaria alternata fungal infection, posing a threat to its production and use, resulting in substantial economic losses. Increasing the density of glandular trichomes enhances disease resistance and improves the production of medicinal metabolites in chrysanthemums. Jasmonate (JA), promotes the formation of glandular trichomes in various plants. However, it remains unclear whether glandular trichome in chrysanthemums are regulated by JA. Grafting, a technique to improve plant resistance to biotic stresses, has been insufficiently explored in its impact on glandular trichomes, terpenoids, and disease resistance. In this study, we demonstrated that grafting with Artemisia vulgaris rootstocks improves the resistance of chrysanthemum scions to A. alternata. Heterografted chrysanthemums exhibited higher trichome density and terpenoid content compared to self-grafted counterparts. Transcriptome analysis highlighted the significant role of CmJAZ1-like in disease resistance in heterografted chrysanthemums. Overexpressing CmJAZ1-like lines exhibited sensitivity to A. alternate, characterized by reduced glandular trichome density and limited terpenoids. Conversely, silencing lines exhibited resistance to A. alternata showcasing increased glandular trichome density and abundant terpenoids. Higher JA content was confirmed in heterografted chrysanthemum scions compared to self-grafted ones. Furthermore, we established that JA promotes the development of glandular trichomes and the synthesis of terpenoids while inducing the degradation of CmJAZ1-like proteins in chrysanthemums. These findings suggest that higher JA increases trichome density and terpenoid content, enhancing resistance to A. alternata by regulating CmJAZ1-like in heterografted chrysanthemums.
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Many bioactive plant cyclic peptides form side-chain-derived macrocycles. Lyciumins, cyclic plant peptides with tryptophan macrocyclizations, are ribosomal peptides (RiPPs) originating from repetitive core peptide motifs in precursor peptides with plant-specific BURP (BNM2, USP, RD22 and PG1beta) domains, but the biosynthetic mechanism for their formation has remained unknown. Here, we characterize precursor-peptide BURP domains as copper-dependent autocatalytic peptide cyclases and use a combination of tandem mass spectrometry-based metabolomics and plant genomics to systematically discover five BURP-domain-derived plant RiPP classes, with mono- and bicyclic structures formed via tryptophans and tyrosines, from botanical collections. As BURP-domain cyclases are scaffold-generating enzymes in plant specialized metabolism that are physically connected to their substrates in the same polypeptide, we introduce a bioinformatic method to mine plant genomes for precursor-peptide-encoding genes by detection of repetitive substrate domains and known core peptide features. Our study sets the stage for chemical, biosynthetic and biological exploration of plant RiPP natural products from BURP-domain cyclases.
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Peptídeos Cíclicos/biossíntese , Peptídeos Cíclicos/química , Proteínas de Plantas/química , Sequência de Aminoácidos , Catálise , Permeabilidade da Membrana Celular , Ciclização , Genoma de Planta , Espectrometria de Massas em TandemRESUMO
Histone deacetylase (HDAC) inhibitors are emerging as promising treatments for hematological malignancies, with potential applications extending to solid tumors in the future. Given their wide-ranging biological effects, there is a pressing need for a thorough understanding of the toxicities linked to HDAC inhibition. In this study, a pharmacovigilance analysis was conducted using the FDA Adverse Event Reporting System database. Suspected adverse events linked to HDAC inhibitors were detected through various statistical methodologies, including reporting odds ratio, proportional reporting ratio, information component, and Empirical Bayes Geometric Mean. Our study findings have illuminated that, among the total reported cases examined, gastrointestinal disorders accounted for 13% patients of the cohort, while lymphatic system disorders comprised 8% cases of the cohort, all of which manifested as adverse events induced by HDAC inhibitors. Importantly, the usage of HDAC inhibitors was found to be associated with incidents of atrial fibrillation, heart failure, respiratory failure, hepatic dysfunction, and acute kidney injury. Romidepsin and belinostat demonstrated more pronounced signals of adverse events compared to panobinostat and vorinostat, emphasizing the need for vigilant monitoring of adverse events in this particular population. Furthermore, atrial fibrillation (clinical priority score of 7 points) emerged as the paramount medical event warranting utmost clinical attention. Eventually, multiple adverse events were observe to emerge within the initial and second months following the initiation of treatment. Vigilant monitoring and supportive care strategies are critical in addressing the toxicities associated with HDAC inhibitors, particularly those concerning cardiotoxicity, respiratory toxicity, renal toxicity, and hepatotoxicity.
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Sistemas de Notificação de Reações Adversas a Medicamentos , Inibidores de Histona Desacetilases , Farmacovigilância , Humanos , Inibidores de Histona Desacetilases/efeitos adversos , Inibidores de Histona Desacetilases/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Vorinostat/efeitos adversos , Panobinostat/efeitos adversos , Ácidos Hidroxâmicos/efeitos adversos , Ácidos Hidroxâmicos/uso terapêutico , Depsipeptídeos/efeitos adversos , Estados Unidos/epidemiologia , Gastroenteropatias/induzido quimicamente , Teorema de Bayes , Neoplasias Hematológicas/tratamento farmacológico , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/tratamento farmacológico , Adolescente , Adulto Jovem , Idoso de 80 Anos ou mais , SulfonamidasRESUMO
Rh(III)-catalyzed C7-alkylation of isatogens (indolin-3-one N-oxides) with malonic acid diazoesters has been developed. This strategy utilizes oxygen anion on the N-oxide group of isatogens as a directing group and successfully achieves the synthesis of a series of C7-alkylated isatogens with moderate to good yields (48-86% yields). Moreover, the N-oxides of isatogens can not only serve as the simple directing group for C7-H bond cleavage but also be deoxidized for easy removal.