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In this study, a novel mitovirus, tentatively designated as "Alternaria alternata mitovirus 2" (AaMV2), was isolated from the fungus Alternaria alternata f. sp. mali causing apple leaf blotch disease. The complete genome of AaMV2 is 3,157 nucleotides in length, with an A+U content of 68.10%. The genome has a single large open reading frame (ORF) encoding an RNA-dependent RNA polymerase (RdRp) protein with a molecular mass of 98.10 kDa. BLAST analysis revealed that AaMV2 has the highest sequence identity to Leptosphaeria biglobosa mitovirus 6, with 79.76% and 82.86% identity at the amino acid and nucleotide level, respectively. Phylogenetic analysis suggested that AaMV2 is a new member of the genus Duamitovirus within the family Mitoviridae. This is the first report of the complete genome sequence analysis of a mitovirus in A. alternata.
Assuntos
Alternaria , Micovírus , Genoma Viral , Malus , Fases de Leitura Aberta , Filogenia , Doenças das Plantas , Vírus de RNA , Sequenciamento Completo do Genoma , Alternaria/virologia , Alternaria/genética , Doenças das Plantas/microbiologia , Malus/microbiologia , Malus/virologia , Micovírus/genética , Micovírus/isolamento & purificação , Micovírus/classificação , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Proteínas Virais/genética , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , Composição de Bases , Folhas de Planta/microbiologia , Folhas de Planta/virologia , Sequência de BasesRESUMO
Efforts directed at improving potency and preparing structurally different TYK2 JH2 inhibitors from the first generation of compounds such as 1a led to the SAR study of new central pyridyl based analogs 2-4. The current SAR study resulted in the identification of 4h as a potent and selective TYK2 JH2 inhibitor with distinct structural differences from 1a. In this manuscript, the in vitro and in vivo profiles of 4h are described. The hWB IC50 of 4h was shown as 41 nM with 94% bioavailability in the mouse PK study.
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Piridinas , TYK2 Quinase , Camundongos , Animais , Relação Estrutura-Atividade , Piridinas/farmacologiaRESUMO
Using the dispersion-corrected density functional theory (DFT-D3) method, we systematically studied the adsorption of 15 kinds of transition-metal (TM) clusters on pristine graphene (Gr) and N-doped graphene (N-Gr). It has been found that TMn (n = 1-4) clusters adsorbed on the N-Gr surface are much stronger than those on the pristine Gr surface, while 3d series clusters present similar geometries on Gr and N-Gr surfaces. The most preferred sites of TMs migrate from hollow to bridge to the top site on the Gr surface along the d series in the periodic table, while the preferred sites of TMs migrate in a much more complex manner on the N-Gr surface. It has also been found that charge transfer decreases along the d series for adsorbed clusters on both surfaces, but adsorbed clusters present less charge transfer on the N-Gr surface than on the Gr surface. What is more interesting is that some TM (Tc, Ru, and Re) clusters change the growth mechanism from the three-dimensional (3D) growth mode on the Gr surface to the two-dimensional (2D) growth mode on the N-Gr surface. At last, it has been found that adsorbed clusters are more dispersed on the N-Gr surface than on the pristine Gr surface due to growth and average aggregation energies.
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Transforming growth factor beta (TGF-ß) is a pleiotropic cytokine that has a wide array of biological effects. For decades, tumor biology implicated TGF-ß as an attractive therapeutic target due to its immunosuppressive effects. Toward this end, multiple pharmaceutical companies developed a number of drug modalities that specifically target the TGF-ß pathway. BMS-986260 is a small molecule, selective TGF-ßR1 kinase inhibitor that was under preclinical development for oncology. In vivo studies across mouse, rat, dog, and monkey and cryopreserved hepatocytes predicted human pharmacokinetics (PK) and distribution of BMS-986260. Efficacy studies of BMS-986260 were undertaken in the MC38 murine colon cancer model, and target engagement, as measured by phosphorylation of SMAD2/3, was assessed in whole blood to predict the clinical efficacious dose. The human clearance is predicted to be low, 4.25 ml/min/kg. BMS-986260 provided a durable and robust antitumor response at 3.75 mg/kg daily and 1.88 mg/kg twice-daily dosing regimens. Phosphorylation of SMAD2/3 was 3.5-fold less potent in human monocytes than other preclinical species. Taken together, the projected clinical efficacious dose was 600 mg QD or 210 mg BID for 3 days followed by a 4-day drug holiday. Mechanism-based cardiovascular findings in the rat ultimately led to the termination of BMS-986260. This study describes the preclinical PK characterization and pharmacodynamics-based efficacious dose projection of a novel small molecule TGF-ßR1 inhibitor.
Assuntos
Adenocarcinoma/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Receptor do Fator de Crescimento Transformador beta Tipo I/antagonistas & inibidores , Adenocarcinoma/patologia , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Cães , Relação Dose-Resposta a Droga , Feminino , Hepatócitos/metabolismo , Humanos , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Distribuição TecidualRESUMO
Synaptic repair in the ischemic brain is a complex process that requires reorganization of the actin cytoskeleton. Ezrin, radixin, and moesin (ERM) are a group of evolutionarily conserved proteins that link the plasma membrane to the actin cytoskeleton and act as scaffolds for signaling transduction. Urokinase-type plasminogen activator (uPA) is a serine proteinase that upon binding to the urokinase-type plasminogen activator receptor (uPAR) catalyzes the conversion of plasminogen into plasmin on the cell surface and activates intracellular signaling pathways. Early studies indicate that uPA and uPAR expression increase during the recovery phase from an ischemic stroke and that uPA binding to uPAR promotes neurorepair in the ischemic brain. The in vitro and in vivo studies presented here show that either the release of neuronal uPA or treatment with recombinant uPA induces the local synthesis of ezrin in the synapse and the recruitment of ß3-integrin to the postsynaptic density (PSD) of cerebral cortical neurons by a plasminogen-independent mechanism. We found that ß3-integrin has a double effect on ezrin, inducing its recruitment to the PSD via the intercellular adhesion molecule-5 (ICAM-5) and its subsequent activation by phosphorylation at Thr-567. Finally, our data indicate that by triggering the reorganization of the actin cytoskeleton in the postsynaptic terminal, active ezrin induces the recovery of dendritic spines and synapses that have been damaged by an acute ischemic stroke. In summary, our data show that uPA-uPAR binding promotes synaptic repair in the ischemic brain via ezrin-mediated reorganization of the actin cytoskeleton in the postsynaptic terminal.
Assuntos
Isquemia Encefálica/metabolismo , Proteínas do Citoesqueleto/metabolismo , Sinapses/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/patologia , Células Cultivadas , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Integrina beta3/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Sinapses/patologiaRESUMO
BACKGROUND: Microglia and CNS-infiltrating monocytes/macrophages (CNS-MPs) perform pro-inflammatory and protective anti-inflammatory functions following ischemic stroke. Selective inhibition of pro-inflammatory responses can be achieved by Kv1.3 channel blockade, resulting in a lower infarct size in the transient middle cerebral artery occlusion (tMCAO) model. Whether beneficial effects of Kv1.3 blockers are mediated by targeting microglia or CNS-infiltrating monocytes/macrophages remains unclear. METHODS: In the 30-min tMCAO mouse model, we profiled functional cell-surface Kv1.3 channels and phagocytic properties of acutely isolated CNS-MPs at various timepoints post-reperfusion. Kv1.3 channels were flow cytometrically detected using fluorescein-conjugated Kv1.3-binding peptide ShK-F6CA as well as by immunohistochemistry. Quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) was performed to measure Kv1.3 (Kcna3) and Kir2.1 (Kcnj2) gene expression. Phagocytosis of 1-µm microspheres by acutely isolated CNS-MPs was measured by flow cytometry. RESULTS: In flow cytometric assays, Kv1.3 channel expression by CD11b+ CNS-MPs was increased between 24 and 72 h post-tMCAO and decreased by 7 days post-tMCAO. Increased Kv1.3 expression was restricted to CD11b+CD45lowLy6clow (microglia) and CD11b+CD45highLy6Clow CNS-MPs but not CD11b+CD45highLy6chigh inflammatory monocytes/macrophages. In immunohistochemical studies, Kv1.3 protein expression was increased in Iba1+ microglia at 24-48 h post-tMCAO. No change in Kv1.3 mRNA in CNS-MPs was observed following tMCAO. CONCLUSIONS: We conclude that resident microglia and a subset of CD45highLy6clow CNS-MPs are the likely cellular targets of Kv1.3 blockers and the delayed phase of neuroinflammation is the optimal therapeutic window for Kv1.3 blockade in ischemic stroke.
Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Canal de Potássio Kv1.3/biossíntese , Fagócitos/metabolismo , Acidente Vascular Cerebral/metabolismo , Animais , Encéfalo/patologia , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Expressão Gênica , Canal de Potássio Kv1.3/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fagócitos/patologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/patologia , Fatores de TempoRESUMO
3ß,23,28-Trihydroxy-12-oleanene 3ß-caffeate (compound 1) is a neuritogenic pentacyclic triterpenoid, which was isolated from Desmodium sambuense based on a PC12 cell bioassay system. Compound 1 induced neurite outgrowth dose-dependently in PC12 cells and primary cortical neurons at doses of 0.1, 0.3, and 1 µM. The potential target of compound 1 was predicted by ChemProteoBase profiling, and the mechanism of action was investigated using specific inhibitors, Western blot analysis, and PC12 [rasN17] and PC12 [mtGAP] mutants. Compound 1 activates endoplasmic reticulum (ER) as an ER stress inducer, and the maker of ER stress GRP78 protein significantly increased after treatment with compound 1. The inhibitors of tyrosine kinase B (TrkB), insulin-like growth factor 1 receptor (IGF-1R), mitogen-activated protein kinase (MEK), and phosphatidylinositol 3 kinase (PI3K) significantly decreased the neurite outgrowth induced by compound 1. Furthermore, the increases of phosphorylation of TrkB, IGF-1R, extracellular signal-regulated kinase (ERK), and protein kinase B (AKT) were observed in the compound 1-treated group, and the phosphorylation of these proteins was diminished by corresponding inhibitors. Thus, the compound-1-induced neuritogenic activity depended on the activation of slight ER stress and associated BDNF-TrkB/Ras/Raf/ERK and IGF-1R/PI3K/AKT signaling pathways in PC12 cells.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ácidos Cafeicos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fabaceae/química , Regulação da Expressão Gênica/efeitos dos fármacos , Neurônios/citologia , Ácido Oleanólico/farmacologia , Triterpenos Pentacíclicos/farmacologia , Extratos Vegetais/farmacologia , Receptor trkB/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Ácidos Cafeicos/química , Chaperona BiP do Retículo Endoplasmático , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ácido Oleanólico/análogos & derivados , Células PC12 , Triterpenos Pentacíclicos/química , Fosforilação , Ratos , Receptor trkB/genética , Transdução de SinaisRESUMO
Upconversion nanoparticle (UCNP)-based luminescence resonance energy transfer (LRET) systems are a powerful tool widely used to detect organic molecules or metal ions because of their simplicity and high sensitivity. The sandwich structure NaYF4:Er3+,Yb3+@NaYF4@NH2 UCNPs, as a highly selective and sensitive aqueous probe for detecting nitroaromatics, has been designed and prepared by a cothermolysis method and modified with polyetherimide to acquire amine groups on the surface of the core/shell UCNPs. The detection principle of nitroaromatics is based on LRET, which forms the Meisnheimer complex between the electron-deficient cyclobenzene of nitroaromatics and the electron-rich amino group on the surface of the sandwich structure UCNPs. As a consequence, nitroaromatics can be brought into close proximity to the sandwich structure UCNPs. With the increase of nitroaromatics (2,4,6-trinitrophenol and 2,4,6-trinitrotoluene) concentrations, the sandwich structure NaYF4:Er3+,Yb3+@NaYF4@NH2 UCNPs display a dramatic luminescent quenching effect at 407 nm and 540 nm under 980 nm excitation. The luminescent quenching intensity of the sandwich structure UCNPs is linearly correlated to the concentration of the nitroaromatics. The detection limit of 2,4,6-trinitrophenol (TNP) and 2,4,6-trinitrotoluene (TNT) are 0.78 and 0.77 ng ml-1, respectively. Therefore, the sandwich structure of NaYF4:Er3+,Yb3+@NaYF4@NH2 UCNPs can act as a valuable probe to detect nitroaromatics in public safety and security conditions.
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AIM: The aims of this study are: (a) to determine the incidence of postoperative delirium (POD) among surgical intensive care unit (ICU) patients in China and identify risk factors, especially, which are modifiable and have value for developing a prediction model; (b) to develop and validate a prediction model of delirium to recognize high-risk patients in surgical ICUs; (c) to investigate the short- and long-term outcomes of delirious patients and identify the predictors of patient outcomes. DESIGN: A single-centre prospective cohort study. METHODS: Patients will be enrolled from three surgical ICUs in a tertiary teaching hospital. Delirium assessment and perioperative data will be collected throughout the hospitalization. Delirious patients will be followed up for 2 years. The study was approved by the ethics committee in May 2018 and was funded by the clinical research grant from Zhongshan hospital, Fudan University, Shanghai. DISCUSSION: Developing POD can be a burden to patients both for the short- and long-term period. Due to the lack of effective treatments for POD, prevention remains the best strategy. This study will provide an effective tool for early screening of high-risk patients of POD and provide a better understanding of the aetiology and outcome of delirium. IMPACT: In clinical practice, a prediction model will offer an effective tool for ICU nurses to assess high-risk patients, which can support them to implement preventive strategies at the early stages to targeted patients. The follow-up results will help us better understand the impact of delirium on patients' long-term outcome.
Assuntos
Delírio/diagnóstico , Delírio/enfermagem , Previsões , Unidades de Terapia Intensiva/estatística & dados numéricos , Complicações Cognitivas Pós-Operatórias/diagnóstico , Complicações Cognitivas Pós-Operatórias/enfermagem , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos de Coortes , Delírio/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Cognitivas Pós-Operatórias/epidemiologia , Estudos Prospectivos , Fatores de RiscoRESUMO
Urokinase-type plasminogen activator (uPA) is a serine proteinase that, upon binding to its receptor (uPAR), catalyzes the conversion of plasminogen into plasmin on the cell surface. Our previous studies indicate that uPA and uPAR expression increase in the ischemic brain during the recovery phase from an acute ischemic injury and that uPA binding to uPAR promotes neurological recovery after an acute ischemic stroke. Here, we used male mice genetically deficient on either uPA (uPA-/-) or uPAR (uPAR-/-) or with a four-amino acid substitution into the growth factor domain of uPA that abrogates its binding to uPAR (PlatGFDhu/GFDhu) to investigate the mechanism whereby uPA promotes neurorepair in the ischemic brain. We found that neurons release uPA and astrocytes recruit uPAR to their plasma membrane during the recovery phase from a hypoxic injury and that binding of neuronal uPA to astrocytic uPAR induces astrocytic activation by a mechanism that does not require plasmin generation, but instead is mediated by extracellular signal-regulated kinase 1/2 (ERK1/2)-regulated phosphorylation of the signal transducer and activator of transcription 3 (STAT3). We report that uPA/uPAR binding is necessary and sufficient to induce astrocytic activation in the ischemic brain and that astrocytes activated by neuronal uPA promote synaptic recovery in neurons that have suffered an acute hypoxic injury via a mechanism mediated by astrocytic thrombospondin-1 (TSP1) and synaptic low-density lipoprotein receptor-related protein-1 (LRP1). In summary, we show that uPA/uPAR-induced astrocytic activation mediates a cross talk between astrocytes and injured neurons that promotes synaptic recovery in the ischemic brain.SIGNIFICANCE STATEMENT To date, there is no therapeutic strategy to promote synaptic recovery in the injured brain. Here, we show that neurons release urokinase-type plasminogen activator (uPA) and astrocytes recruit the uPA receptor (uPAR) to their plasma membrane during the recovery phase from a hypoxic injury. We found that binding of neuronal uPA to astrocytic uPAR promotes astrocytic activation and that astrocytes activated by uPA-uPAR binding promote synaptic recovery in neurons that have suffered a hypoxic injury by a mechanism that does not require plasmin generation, but instead is mediated by ERK1/2-regulated STAT3 phosphorylation, astrocytic thrombospondin-1 (TSP1) and synaptic low-density lipoprotein receptor-related protein-1 (LRP1). Our work unveils a new biological function for uPA-uPAR as mediator of a neuron-astrocyte cross talk that promotes synaptic recovery in the ischemic brain.
Assuntos
Astrócitos/metabolismo , Isquemia Encefálica/metabolismo , Receptor Cross-Talk/fisiologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Sinapses/fisiologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Astrócitos/patologia , Isquemia Encefálica/patologia , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia , Recuperação de Função Fisiológica/fisiologiaRESUMO
Axonal injury is a common cause of neurological dysfunction. Unfortunately, in contrast to axons from the peripheral nervous system, the limited capacity of regeneration of central nervous system (CNS) axons is a major obstacle for functional recovery in patients suffering neurological diseases that involve the subcortical white matter. Urokinase-type plasminogen activator (uPA) is a serine proteinase that upon binding to the urokinase-type plasminogen activator receptor (uPAR) catalyzes the conversion of plasminogen into plasmin on the cell surface. uPAR expression increases after an injury, and signaling through uPAR promotes tissue remodeling. However, it is yet unknown whether uPA binding to uPAR has an effect on axonal recovery in the CNS. Here, we used in vitro and in vivo models of CNS axonal injury to test the hypothesis that uPA binding to uPAR promotes axonal regeneration in the CNS. We found that newly formed growth cones from axons re-emerging from an axonal injury express uPAR and that binding of uPA to this uPAR promotes axonal recovery by a mechanism that does not require the generation of plasmin. Our data indicate that the binding of recombinant uPA or endogenous uPA to uPAR induces membrane recruitment and activation of ß1 integrin via the low density lipoprotein receptor-related protein-1 (LRP1), which leads to activation of the Rho family small GTPase Rac1 and Rac1-induced axonal regeneration. Our results show that the uPA/uPAR/LRP1 system is a potential target for the development of therapeutic strategies to promote axonal recovery following a CNS injury.
Assuntos
Axônios/fisiologia , Sistema Nervoso Central/metabolismo , Regeneração Nervosa , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Humanos , Integrina beta1/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Ligação ProteicaRESUMO
BACKGROUND: Polymerase δ-interacting protein 2 (Poldip2) is a multifunctional protein that regulates vascular extracellular matrix composition and matrix metalloproteinase (MMP) activity. The blood-brain barrier (BBB) is a dynamic system assembled by endothelial cells, basal lamina, and perivascular astrocytes, raising the possibility that Poldip2 may be involved in maintaining its structure. We investigated the role of Poldip2 in the late BBB permeability induced by cerebral ischemia. METHODS: Transient middle cerebral artery occlusion (tMCAO) was induced in Poldip2+/+ and Poldip2+/- mice. The volume of the ischemic lesion was measured in triphenyltetrazolium chloride-stained sections. BBB breakdown was evaluated by Evans blue dye extravasation. Poldip2 protein expression was evaluated by western blotting. RT-PCR, zymography, and ELISAs were used to measure mRNA levels, activity, and protein levels of cytokines and MMPs. Cultured astrocytes were transfected with Poldip2 siRNA, and mRNA levels of cytokines were evaluated as well as IκBα protein degradation. RESULTS: Cerebral ischemia induced the expression of Poldip2. Compared to Poldip2+/+ mice, Poldip2+/- animals exhibited decreased Evans blue dye extravasation and improved survival 24 h following stroke. Poldip2 expression was upregulated in astrocytes exposed to oxygen and glucose deprivation (OGD) and siRNA-mediated downregulation of Poldip2 abrogated OGD-induced IL-6 and TNF-α expression. In addition, siRNA against Poldip2 inhibited TNF-α-induced IκBα degradation. TNF-α, IL-6, MCP-1, VEGF, and MMP expression induced by cerebral ischemia was abrogated in Poldip2+/- mice. The protective effect of Poldip2 depletion on the increased permeability of the BBB was partially reversed by systemic administration of TNF-α. CONCLUSIONS: Poldip2 is upregulated following ischemic stroke and mediates the breakdown of the BBB by increasing cerebral cytokine production and MMP activation. Therefore, Poldip2 appears to be a promising novel target for the development of therapeutic strategies to prevent the development of cerebral edema in the ischemic brain.
Assuntos
Barreira Hematoencefálica/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/prevenção & controle , Permeabilidade Capilar/fisiologia , Proteínas Mitocondriais/deficiência , Neuroproteção/fisiologia , Proteínas Nucleares/deficiência , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Isquemia Encefálica/diagnóstico por imagem , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos TransgênicosRESUMO
Ag-Eu3+ co-doped fluoroborate glass phosphors doped with various Eu3+-concentrations were prepared by a melt-quenching technique. The luminescent properties of these glass phosphors were characterized by excitation and emission spectra. Broad excitation and emission bands located, respectively, at 300-450 nm and 390-700 nm originating from silver aggregates were observed. Strong red emissions were detected under 404 nm violet light-emitting diode (LED) excitation for those Ag-Eu3+ co-doped samples. It was found that these red emissions of Eu3+ well compensated the deficiency of the red spectral components in glasses containing Ag aggregates. In addition, it was confirmed that stable white light could be achieved from the combination of a specific Ag-Eu3+ co-doped fluoroborate glass phosphor and LEDs with different output wavelengths. By adjusting the luminescence intensity ratio of the glass phosphor to the 404 nm violet LED, tunable emitting color was realized, and the studied glass phosphors showed excellent emitting color stability toward LED drive currents. Our results demonstrated that this kind of easy fabrication, low-cost, and highly stable Ag-Eu3+ co-doped fluoroborate glass phosphors had potential application in white LED.
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Asexual and sexual reproduction are the most important biological events in the life cycle of phytopathogenic and toxigenic Fusarium and are responsible for disease epidemics. However, the signaling molecules which induce the asexual reproduction of Fusarium are unknown. Herein we describe the structure elucidation, including the absolute configuration, of Fusarium asexual reproduction inducer (FARI), a new sesquiterpene derivative, by spectroscopic analysis, total synthesis, and conidium-inducing assays of synthetic isomers. We have also uncovered the universality of FARI among Fusarium species. Moreover, a mechanism-of-action study suggested that the Gpmk1 and LaeA signaling pathways are required for conidium formation induced by FARI; conversely, the Mgv1 of mitogen-activated protein kinase is not involved in conidium formation. FARI exhibited conidium-inducing activity at an extremely low dose and high stereoselectivity, which may suggest the presence of a stereospecific target.
Assuntos
Fusarium/fisiologia , Reprodução Assexuada/fisiologia , Sesquiterpenos/metabolismo , Proteínas Fúngicas/metabolismo , Fusarium/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Reprodução Assexuada/efeitos dos fármacos , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Transdução de Sinais , Esporos Fúngicos/efeitos dos fármacos , EstereoisomerismoRESUMO
Inhibition of signal transduction downstream of the IL-23 receptor represents an intriguing approach to the treatment of autoimmunity. Using a chemogenomics approach marrying kinome-wide inhibitory profiles of a compound library with the cellular activity against an IL-23-stimulated transcriptional response in T lymphocytes, a class of inhibitors was identified that bind to and stabilize the pseudokinase domain of the Janus kinase tyrosine kinase 2 (Tyk2), resulting in blockade of receptor-mediated activation of the adjacent catalytic domain. These Tyk2 pseudokinase domain stabilizers were also shown to inhibit Tyk2-dependent signaling through the Type I interferon receptor but not Tyk2-independent signaling and transcriptional cellular assays, including stimulation through the receptors for IL-2 (JAK1- and JAK3-dependent) and thrombopoietin (JAK2-dependent), demonstrating the high functional selectivity of this approach. A crystal structure of the pseudokinase domain liganded with a representative example showed the compound bound to a site analogous to the ATP-binding site in catalytic kinases with features consistent with high ligand selectivity. The results support a model where the pseudokinase domain regulates activation of the catalytic domain by forming receptor-regulated inhibitory interactions. Tyk2 pseudokinase stabilizers, therefore, represent a novel approach to the design of potent and selective agents for the treatment of autoimmunity.
Assuntos
Modelos Moleculares , Transdução de Sinais , Linfócitos T/enzimologia , TYK2 Quinase/química , Cristalografia por Raios X , Estabilidade Enzimática , Humanos , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Janus Quinase 3/genética , Janus Quinase 3/metabolismo , Estrutura Terciária de Proteína , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/metabolismo , Receptores de Trombopoetina/genética , Receptores de Trombopoetina/metabolismo , TYK2 Quinase/genéticaRESUMO
Spines are dendritic protrusions that receive most of the excitatory input in the brain. Early after the onset of cerebral ischemia dendritic spines in the peri-infarct cortex are replaced by areas of focal swelling, and their re-emergence from these varicosities is associated with neurological recovery after acute ischemic stroke (AIS). Urokinase-type plasminogen activator (uPA) is a serine proteinase that plays a central role in tissue remodeling via binding to the urokinase plasminogen activator receptor (uPAR). We report that cerebral cortical neurons release uPA during the recovery phase from ischemic stroke in vivo or hypoxia in vitro. Although uPA does not have an effect on ischemia- or hypoxia-induced neuronal death, genetic deficiency of uPA (uPA(-/-)) or uPAR (uPAR(-/-)) abrogates functional recovery after AIS. Treatment with recombinant uPA after ischemic stroke induces neurological recovery in wild-type and uPA(-/-) but not in uPAR(-/-) mice. Diffusion tensor imaging studies indicate that uPA(-/-) mice have increased water diffusivity and decreased anisotropy associated with impaired dendritic spine recovery and decreased length of distal neurites in the peri-infarct cortex. We found that the excitotoxic injury induces the clustering of uPAR in dendritic varicosities, and that the binding of uPA to uPAR promotes the reorganization of the actin cytoskeleton and re-emergence of dendritic filopodia from uPAR-enriched varicosities. This effect is independent of uPA's proteolytic properties and instead is mediated by Rac-regulated profilin expression and cofilin phosphorylation. Our data indicate that binding of uPA to uPAR promotes dendritic spine recovery and improves functional outcome following AIS.
Assuntos
Isquemia Encefálica/enzimologia , Espinhas Dendríticas/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/enzimologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Células Cultivadas , Espinhas Dendríticas/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/enzimologia , Doenças do Sistema Nervoso/patologia , Ligação Proteica/fisiologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Resultado do Tratamento , Ativador de Plasminogênio Tipo Uroquinase/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/uso terapêuticoRESUMO
In this study, the microstructural evolution and mechanical properties of Ti6Al4V titanium alloy welded joints subjected to ultrasonic assisted laser welding were scrutinized, while numerical simulations were employed to explicate the grain refinement mechanism. The simulations indicate that the ultrasonic vibration significantly improves the overall fluidity and temperature of the molten pool. Under the identical condition of laser power and welding speed (1500 W, 1.3 m/min), the presence of 0.2A ultrasonic current yields a more uniform refinement of columnar grains, along with a denser arrangement of acicular martensite. The refinement mechanism can be attributed to the small temperature gradient, cavitation effects, and stress induced by ultrasonic vibration. Notably, the welded joint attains a peak tensile strength of 945.2 MPa under the aforementioned 0.2A condition, distinctly demonstrating the characteristics of ductile fracture. This research further reveals the underlying mechanism of grain refinement in Ti6Al4V alloy laser-welded joints induced by ultrasonic vibration, providing valuable references for optimizing process parameters and improving the quality of such welded joints.
RESUMO
Mycoviruses have been found in various fungal species across different taxonomic groups, while no viruses have been reported yet in the fungus Exserohilum rostratum. In this study, a novel orfanplasmovirus, namely Exserohilum rostratum orfanplasmovirus 1 (ErOrfV1), was identified in the Exserohilum rostratum strain JZ1 from maize leaf. The complete genome of ErOrfV1 consists of two positive single-stranded RNA segments, encoding an RNA-dependent RNA polymerase and a hypothetical protein with unknown function, respectively. Phylogenetic analysis revealed that ErOrfV1 clusters with other orfanplasmoviruses, forming a distinct phyletic clade. A new family, Orfanplasmoviridae, is proposed to encompass this newly discovered ErOrfV1 and its associated orfanplasmoviruses. ErOrfV1 exhibits effective vertical transmission through conidia, as evidenced by its 100% presence in over 200 single conidium isolates. Moreover, it can be horizontally transmitted to Exserohilum turcicum. Additionally, the infection of ErOrfV1 is cryptic in E. turcicum because there were no significant differences in mycelial growth rate and colony morphology between ErOrfV1-infected and ErOrfV1-free strains. This study represents the inaugural report of a mycovirus in E. rostratum, as well as the first documentation of the biological and transmission characteristics of orfanplasmovirus. These discoveries significantly contribute to our understanding of orfanplasmovirus.
RESUMO
The dipeptide Tyr-Pro has physiological potential for intact transportability into the brain parenchyma, prevention of cognitive impairment, and an adiponectin receptor 1 (AdipoR1) agonistic effect. The present study aimed to understand the effect of Tyr-Pro on the acetylcholine (ACh) nervous system and its underlying mechanism in NE-4C nerve cells. Concentration-dependent ACh production was induced by stimulation with Tyr-Pro and AdipoRon (an AdipoR1 agonist), along with the expression of AdipoR1 and choline acetyltransferase (ChAT) in NE-4C cells. By knocking down AdipoR1 in the cells, Tyr-Pro promoted ChAT expression, along with the activations of AMPK and ERK 1/2. Tyr-Pro did not alter acetylcholinesterase or ACh receptors, indicating that the dipeptide might operate as an ACh accelerator in nerve cells. This study provides the first evidence that the AdipoR1 agonistic Tyr-Pro is a promising dipeptide responsible for the stimulation of the ACh nervous system by AdipoR1-induced ChAT activation.
Assuntos
Acetilcolina , Acetilcolinesterase , Acetilcolina/farmacologia , Acetilcolina/metabolismo , Acetilcolinesterase/metabolismo , Adiponectina/metabolismo , Dipeptídeos/farmacologia , Dipeptídeos/metabolismo , Neurônios , Proteínas de TransporteRESUMO
Chlamydia psittaci-a zoonotic pathogen in birds-may be transmitted to humans, causing severe respiratory disease. Individuals working in or living near poultry farms are highly susceptible to C. psittaci infection. In this study, we assessed the prevalence and genotypes of C. psittaci in poultries and humans in three cities of China by collecting fecal samples from different poultry species and throat swab samples and serum samples from workers in poultry farms and zoos. These samples were screened by real-time fluorescence quantitative PCR (qPCR) targeting C. psittaci ompA. The positive samples were subjected to PCR amplification and sequencing of ompA. The strains detected in the samples were genotyped on the basis of the phylogenetic analysis of ompA sequences. In total, 3.13% (40/1278) poultry fecal samples were positive in the qPCR assay, whereas 3.82% (6/157) of throat swab samples and 42.59% (46/108) of serum samples from the workers were positive in the qPCR and indirect fluorescent antibody assays, respectively. The strains detected in the 32 poultry samples and 6 human samples were genotyped as type A, indicating that the workers were infected with C. psittaci that originated in poultry birds in farms. Additionally, eight peacocks showed strains with the genotype CPX0308, which was identified in China for the first time. Elucidating the distribution of C. psittaci in animals and poultry-related workers may provide valuable insights for reducing the risk of C. psittaci infection within a population.