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1.
Mol Cell ; 82(1): 177-189.e4, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34936881

RESUMO

The DNA-dependent protein kinase (DNA-PK) initially protects broken DNA ends but then promotes their processing during non-homologous end joining (NHEJ). Before ligation by NHEJ, DNA hairpin ends generated during V(D)J recombination must be opened by the Artemis nuclease, together with autophosphorylated DNA-PK. Structures of DNA-PK bound to DNA before and after phosphorylation, and in complex with Artemis and a DNA hairpin, reveal an essential functional switch. When bound to open DNA ends in its protection mode, DNA-PK is inhibited for cis-autophosphorylation of the so-called ABCDE cluster but activated for phosphorylation of other targets. In contrast, DNA hairpin ends promote cis-autophosphorylation. Phosphorylation of four Thr residues in ABCDE leads to gross structural rearrangement of DNA-PK, widening the DNA binding groove for Artemis recruitment and hairpin cleavage. Meanwhile, Artemis locks DNA-PK into the kinase-inactive state. Kinase activity and autophosphorylation of DNA-PK are regulated by different DNA ends, feeding forward to coordinate NHEJ events.


Assuntos
Dano ao DNA , Reparo do DNA por Junção de Extremidades , DNA de Neoplasias/metabolismo , Proteína Quinase Ativada por DNA/metabolismo , Neoplasias do Colo do Útero/enzimologia , DNA de Neoplasias/genética , Proteína Quinase Ativada por DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Ativação Enzimática , Feminino , Células HEK293 , Células HeLa , Humanos , Autoantígeno Ku/genética , Autoantígeno Ku/metabolismo , Conformação de Ácido Nucleico , Fosforilação , Ligação Proteica , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
2.
Plant J ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38872484

RESUMO

Acteoside is a bioactive phenylethanoid glycoside widely distributed throughout the plant kingdom. Because of its two catechol moieties, acteoside displays a variety of beneficial activities. The biosynthetic pathway of acteoside has been largely elucidated, but the assembly logic of two catechol moieties in acteoside remains unclear. Here, we identified a novel polyphenol oxidase OfPPO2 from Osmanthus fragrans, which could hydroxylate various monophenolic substrates, including tyrosine, tyrosol, tyramine, 4-hydroxyphenylacetaldehyde, salidroside, and osmanthuside A, leading to the formation of corresponding catechol-containing intermediates for acteoside biosynthesis. OfPPO2 could also convert osmanthuside B into acteoside, creating catechol moieties directly via post-modification of the acteoside skeleton. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis and subcellular localization assay further support the involvement of OfPPO2 in acteoside biosynthesis in planta. These findings suggest that the biosynthesis of acteoside in O. fragrans may follow "parallel routes" rather than the conventionally considered linear route. In support of this hypothesis, the glycosyltransferase OfUGT and the acyltransferase OfAT could direct the flux of diphenolic intermediates generated by OfPPO2 into acteoside. Significantly, OfPPO2 and its orthologs constitute a functionally conserved enzyme family that evolved independently from other known biosynthetic enzymes of acteoside, implying that the substrate promiscuity of this PPO family may offer acteoside-producing plants alternative ways to synthesize acteoside. Overall, this work expands our understanding of parallel pathways plants may employ to efficiently synthesize acteoside, a strategy that may contribute to plants' adaptation to environmental challenges.

3.
Nat Chem Biol ; 19(6): 731-739, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36759751

RESUMO

Bioluminescence imaging (BLI) allows non-invasive visualization of cells and biochemical events in vivo and thus has become an indispensable technique in biomedical research. However, BLI in the central nervous system remains challenging because luciferases show relatively poor performance in the brain with existing substrates. Here, we report the discovery of a NanoLuc substrate with improved brain performance, cephalofurimazine (CFz). CFz paired with Antares luciferase produces greater than 20-fold more signal from the brain than the standard combination of D-luciferin with firefly luciferase. At standard doses, Antares-CFz matches AkaLuc-AkaLumine/TokeOni in brightness, while occasional higher dosing of CFz can be performed to obtain threefold more signal. CFz should allow the growing number of NanoLuc-based indicators to be applied to the brain with high sensitivity. Using CFz, we achieve video-rate non-invasive imaging of Antares in brains of freely moving mice and demonstrate non-invasive calcium imaging of sensory-evoked activity in genetically defined neurons.


Assuntos
Diagnóstico por Imagem , Medições Luminescentes , Camundongos , Animais , Medições Luminescentes/métodos , Encéfalo/diagnóstico por imagem , Luciferina de Vaga-Lumes , Luciferinas
4.
J Immunol ; 210(10): 1494-1507, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37010945

RESUMO

IFN-stimulated genes (ISGs) can act as effector molecules against viral infection and can also regulate pathogenic infection and host immune response. N-Myc and STAT interactor (Nmi) is reported as an ISG in mammals and in fish. In this study, the expression of Nmi was found to be induced significantly by the infection of Siniperca chuatsi rhabdovirus (SCRV), and the induced expression of type I IFNs after SCRV infection was reduced following Nmi overexpression. It is observed that Nmi can interact with IRF3 and IRF7 and promote the autophagy-mediated degradation of these two transcription factors. Furthermore, Nmi was found to be interactive with IFP35 through the CC region to inhibit IFP35 protein degradation, thereby enhancing the negative role in type I IFN expression after viral infection. In turn, IFP35 is also capable of protecting Nmi protein from degradation through its N-terminal domain. It is considered that Nmi and IFP35 in fish can also interact with each other in regulating negatively the expression of type I IFNs, but thus in enhancing the replication of SCRV.


Assuntos
Interferon Tipo I , Peptídeos e Proteínas de Sinalização Intracelular , Animais , Interferon Tipo I/metabolismo , Peixes
5.
J Immunol ; 210(11): 1771-1789, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37017564

RESUMO

The type IV IFN (IFN-υ) is reported in vertebrates from fish to primary mammals with IFN-υR1 and IL-10R2 as receptor subunits. In this study, the proximal promoter of IFN-υ was identified in the amphibian model, Xenopus laevis, with functional IFN-sensitive responsive element and NF-κB sites, which can be transcriptionally activated by transcription factors, such as IFN regulatory factor (IRF)1, IRF3, IRF7, and p65. It was further found that IFN-υ signals through the classical IFN-stimulated gene (ISG) factor 3 (ISGF3) to induce the expression of ISGs. It seems likely that the promoter elements of the IFN-υ gene in amphibians is similar to type III IFN genes, and that the mechanism involved in IFN-υ induction is very much similar to type I and III IFNs. Using recombinant IFN-υ protein and the X. laevis A6 cell line, >400 ISGs were identified in the transcriptome, including ISGs homologous to humans. However, as many as 268 genes were unrelated to human or zebrafish ISGs, and some of these ISGs were expanded families such as the amphibian novel TRIM protein (AMNTR) family. AMNTR50, a member in the family, was found to be induced by type I, III, and IV IFNs through IFN-sensitive responsive element sites of the proximal promoter, and this molecule has a negative role in regulating the expression of type I, III, and IV IFNs. It is considered that the current study contributes to the understanding of transcription, signaling, and functional aspects of type IV IFN at least in amphibians.


Assuntos
Interferon Tipo I , Interferons , Animais , Humanos , Xenopus laevis , Interferons/genética , Interferons/metabolismo , Peixe-Zebra/metabolismo , Regulação da Expressão Gênica , Transdução de Sinais , Interferon Tipo I/metabolismo , Mamíferos/metabolismo
6.
Stroke ; 55(6): 1468-1476, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38747162

RESUMO

BACKGROUND: Normobaric hyperoxia (NBO) has neuroprotective effects in acute ischemic stroke. Thus, we aimed to identify the optimal NBO treatment duration combined with endovascular treatment. METHODS: This is a single-center, randomized controlled, open-label, blinded-end point dose-escalation clinical trial. Patients with acute ischemic stroke who had an indication for endovascular treatment at Tianjin Huanhu Hospital were randomly assigned to 4 groups (1:1 ratio) based on NBO therapy duration: (1) control group (1 L/min oxygen for 4 hours); (2) NBO-2h group (10 L/min for 2 hours); (3) NBO-4h group (10 L/min for 4 hours); and (4) NBO-6h group (10 L/min for 6 hours). The primary outcome was cerebral infarction volume at 72 hours after randomization using an intention-to-treat analysis model. The primary safety outcome was the 90-day mortality rate. RESULTS: Between June 2022 and September 2023, 100 patients were randomly assigned to the following groups: control group (n=25), NBO-2h group (n=25), NBO-4h group (n=25), and NBO-6h group (n=25). The 72-hour cerebral infarct volumes were 39.4±34.3 mL, 30.6±30.1 mL, 19.7±15.4 mL, and 22.6±22.4 mL, respectively (P=0.013). The NBO-4h and NBO-6h groups both showed statistically significant differences (adjusted P values: 0.011 and 0.027, respectively) compared with the control group. Compared with the control group, both the NBO-4h and NBO-6h groups showed significant differences (P<0.05) in the National Institutes of Health Stroke Scale scores at 24 hours, 72 hours, and 7 days, as well as in the change of the National Institutes of Health Stroke Scale scores from baseline to 24 hours. Additionally, there were no significant differences among the 4 groups in terms of 90-day mortality rate, symptomatic intracranial hemorrhage, early neurological deterioration, or severe adverse events. CONCLUSIONS: The effectiveness of NBO therapy was associated with oxygen administration duration. Among patients with acute ischemic stroke who underwent endovascular treatment, NBO therapy for 4 and 6 hours was found to be more effective. Larger-scale multicenter studies are needed to validate these findings. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05404373.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Procedimentos Endovasculares/métodos , Idoso , AVC Isquêmico/terapia , Hiperóxia , Resultado do Tratamento , Terapia Combinada , Oxigenoterapia/métodos
7.
Anal Chem ; 96(25): 10467-10475, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38863336

RESUMO

"Signal-off" nanozyme sensing platforms are usually employed to detect analytes (e.g., ascorbic acid (AA) and alkaline phosphatase (ALP)), which are mostly based on oxidase (OXD) nanozymes. However, their drawbacks, like dissolved oxygen-dependent catalysis capability, relatively low enzyme activity, limited amount, and kind, may not favor sensing platforms' optimization. Meanwhile, with the need for sustainable development, a reusable "signal-off" sensing platform is essential for cutting down the cost of the assay, but it is rarely developed in previous studies. Magnetic peroxidase (POD) nanozymes potentially make up the deficiencies and become reusable and better "signal-off" sensing platforms. As a proof of concept, we first construct Fe3O4@polydopamine-supported Pt/Ru alloy nanoparticles (IOP@Pt/Ru) without stabilizers. IOP@Pt/Ru shows high POD activity with Vmax of 83.24 × 10-8 M·s-1 for 3,3',5,5'-Tetramethylbenzidine (TMB) oxidation. Meanwhile, its oxidation rate for TMB is slower than the reduction of oxidized TMB by reducers, favorable for a more significant detection signal. On the other hand, IOP@Pt/Ru possesses great magnet-responsive capability, making itself be recycled and reused for at least 15-round catalysis. When applying IOP@Pt/Ru for AA (ALP) detection, it performs better detectable adaptability, with a linear range of 0.01-0.2 mM (0.1-100 U/L) and a limit of detection of 0.01 mM (0.05 U/L), superior to most of OXD nanozyme-based ALP sensing platform. Finally, IOP@Pt/Ru's reusable assay was demonstrated in real blood samples for ALP assay, which has never been explored in previous studies. Overall, this study develops a reusable "signal-off" nanozyme sensing platform with superior assay capabilities than traditional OXD nanozymes, paves a new way to optimize nanozyme-based "signal-off" sensing platforms, and provides an idea for constructing inexpensive and sustainable sensing platforms.


Assuntos
Ligas , Peroxidase , Platina , Platina/química , Ligas/química , Peroxidase/química , Peroxidase/metabolismo , Benzidinas/química , Limite de Detecção , Oxirredução , Polímeros/química , Humanos , Catálise , Técnicas Biossensoriais/métodos , Ácido Ascórbico/análise , Ácido Ascórbico/química , Indóis
8.
Anal Chem ; 96(19): 7487-7496, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38695134

RESUMO

Cinchona alkaloid derivatives as Brønsted base catalysts have attracted considerable attention in the field of asymmetric catalysis. However, their potential application as chiral solvating agents has not been described. In this research, we investigated the use of the Cinchona alkaloid dimer, namely, (DHQ)2PHAL, as a chiral solvating agent for discerning various mandelic acid derivatives through 1H NMR spectroscopy. The addition of catalytic amounts of DMAP facilitated this process. Our experimental results demonstrate that dimeric (DHQ)2PHAL exhibits remarkable chiral discrimination properties regarding the diagnostic split protons of 1H NMR signals (including 24 examples, up to 0.321 ppm). Furthermore, it serves as an excellent chiral discriminating agent and provides good resolution for racemic chiral phosphoric acid as determined by 31P NMR spectroscopy. The quality of enantiodifferentiation has also been evaluated by means of the parameter "resolution (Rs)". Significantly, this class of CSAs based on (alkaloid)2linker systems with an azaaromatic linker can be directly employed, which is commercially available in an enantiopure form at very low cost and exhibits promising potential in determining the enantiopurity of α-hydroxy acids by chemoselective and biocatalytic reactions.

9.
Chembiochem ; 25(10): e202400107, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38536122

RESUMO

This study characterizes the acceptor specificity of levansucrases (LSs) from Gluconobacter oxydans (LS1), Vibrio natriegens (LS2), Novosphingobium aromaticivorans (LS3), and Paraburkholderia graminis (LS4) using sucrose as fructosyl donor and selected phenolic compounds and carbohydrates as acceptors. Overall, V. natriegens LS2 proved to be the best biocatalyst for the transfructosylation of phenolic compounds. More than one fructosyl unit could be attached to fructosylated phenolic compounds. The transfructosylation of epicatechin by P. graminis LS4 resulted in the most diversified products, with up to five fructosyl units transferred. In addition to the LS source, the acceptor specificity of LS towards phenolic compounds and their transfructosylation products were found to greatly depend on their chemical structure: the number of phenolic rings, the reactivity of hydroxyl groups and the presence of aliphatic chains or methoxy groups. Similarly, for carbohydrates, the transfructosylation yield was dependent on both the LS source and the acceptor type. The highest yield of fructosylated-trisaccharides was Erlose from the transfructosylation of maltose catalyzed by LS2, with production reaching 200 g/L. LS2 was more selective towards the transfructosylation of phenolic compounds and carbohydrates, while reactions catalyzed by LS1, LS3 and LS4 also produced fructooligosaccharides. This study shows the high potential for the application of LSs in the glycosylation of phenolic compounds and carbohydrates.


Assuntos
Biocatálise , Hexosiltransferases , Fenóis , Hexosiltransferases/metabolismo , Hexosiltransferases/química , Fenóis/metabolismo , Fenóis/química , Glicosilação , Especificidade por Substrato , Vibrio/enzimologia , Gluconobacter oxydans/enzimologia , Gluconobacter oxydans/metabolismo , Carboidratos/química
10.
J Transl Med ; 22(1): 23, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178174

RESUMO

BACKGROUND: Inflammatory response has been recognized as a pivotal pathophysiological process during cerebral ischemia. ChemR23 signaling is involved in the pathophysiology of various inflammatory diseases. Nevertheless, the role of ChemR23 signaling in ischemic stroke remains largely unknown. METHODS: Permanent ischemic stroke mouse model was accomplished by middle cerebral artery occlusion (MCAO). Resolvin E1 (RvE1) or chemerin-9 (C-9), the agonists of ChemR23, were administered by intracerebroventricular (i.c.v) injection before MCAO induction. Then, analysis of neurobehavioral deficits and brain sampling were done at Day 1 after MCAO. The brain samples were further analyzed by histological staining, immunofluorescence, RNA sequencing, ELISA, transmission electron microscope, and western blots. Furthermore, oxygen-glucose deprivation (OGD) was employed in SH-SY5Y to mimic MCAO in vitro, and ChemR23 signaling pathway was further studied by overexpression of ChemR23 or administration of related agonists or antagonists. Analysis of cell death and related pathway markers were performed. RESULTS: ChemR23 expression was upregulated following MCAO. Under in vitro and in vivo ischemic conditions, ChemR23 deficiency or inhibition contributed to excessive NLRP3-mediated maturation and release of IL-1ß and IL-18, as well as enhanced cleavage of GSDMD-N and neuronal pyroptosis. These influences ultimately aggravated brain injury and neuronal damage. On the other hand, ChemR23 activation by RvE1 or C-9 mitigated the above pathophysiological abnormalities in vivo and in vitro, and overexpression of ChemR23 in SH-SY5Y cells also rescued OGD-induced neuronal pyroptosis. Blockade of NLRP3 mimics the protective effects of ChemR23 activation in vitro. CONCLUSION: Our data indicated that ChemR23 modulates NLRP3 inflammasome-mediated neuronal pyroptosis in ischemic stroke. Activation of ChemR23 may serve as a promising potential target for neuroprotection in cerebral ischemia.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Neuroblastoma , Receptores de Quimiocinas , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Quimiocinas , Infarto da Artéria Cerebral Média/complicações , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , AVC Isquêmico/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Traumatismo por Reperfusão/patologia , Transdução de Sinais , Receptores de Quimiocinas/metabolismo
11.
Plant Physiol ; 192(1): 666-679, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36881883

RESUMO

The active structural change of actin cytoskeleton is a general host response upon pathogen attack. This study characterized the function of the cotton (Gossypium hirsutum) actin-binding protein VILLIN2 (GhVLN2) in host defense against the soilborne fungus Verticillium dahliae. Biochemical analysis demonstrated that GhVLN2 possessed actin-binding, -bundling, and -severing activities. A low concentration of GhVLN2 could shift its activity from actin bundling to actin severing in the presence of Ca2+. Knockdown of GhVLN2 expression by virus-induced gene silencing reduced the extent of actin filament bundling and interfered with the growth of cotton plants, resulting in the formation of twisted organs and brittle stems with a decreased cellulose content of the cell wall. Upon V. dahliae infection, the expression of GhVLN2 was downregulated in root cells, and silencing of GhVLN2 enhanced the disease tolerance of cotton plants. The actin bundles were less abundant in root cells of GhVLN2-silenced plants than in control plants. However, upon infection by V. dahliae, the number of actin filaments and bundles in the cells of GhVLN2-silenced plants was raised to a comparable level as those in control plants, with the dynamic remodeling of the actin cytoskeleton appearing several hours in advance. GhVLN2-silenced plants exhibited a higher incidence of actin filament cleavage in the presence of Ca2+, suggesting that pathogen-responsive downregulation of GhVLN2 could activate its actin-severing activity. These data indicate that the regulated expression and functional shift of GhVLN2 contribute to modulating the dynamic remodeling of the actin cytoskeleton in host immune responses against V. dahliae.


Assuntos
Ascomicetos , Verticillium , Gossypium/metabolismo , Resistência à Doença/genética , Actinas/metabolismo , Cálcio/metabolismo , Verticillium/fisiologia , Ascomicetos/metabolismo , Citoesqueleto de Actina/metabolismo , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
12.
BMC Cancer ; 24(1): 307, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448945

RESUMO

BACKGROUND: Preoperative prediction of International Federation of Gynecology and Obstetrics (FIGO) stage in patients with epithelial ovarian cancer (EOC) is crucial for determining appropriate treatment strategy. This study aimed to explore the value of contrast-enhanced CT (CECT) radiomics in predicting preoperative FIGO staging of EOC, and to validate the stability of the model through an independent external dataset. METHODS: A total of 201 EOC patients from three centers, divided into a training cohort (n = 106), internal (n = 46) and external (n = 49) validation cohorts. The least absolute shrinkage and selection operator (LASSO) regression algorithm was used for screening radiomics features. Five machine learning algorithms, namely logistic regression, support vector machine, random forest, light gradient boosting machine (LightGBM), and decision tree, were utilized in developing the radiomics model. The optimal performing algorithm was selected to establish the radiomics model, clinical model, and the combined model. The diagnostic performances of the models were evaluated through receiver operating characteristic analysis, and the comparison of the area under curves (AUCs) were conducted using the Delong test or F-test. RESULTS: Seven optimal radiomics features were retained by the LASSO algorithm. The five radiomics models demonstrate that the LightGBM model exhibits notable prediction efficiency and robustness, as evidenced by AUCs of 0.83 in the training cohort, 0.80 in the internal validation cohort, and 0.68 in the external validation cohort. The multivariate logistic regression analysis indicated that carcinoma antigen 125 and tumor location were identified as independent predictors for the FIGO staging of EOC. The combined model exhibited best diagnostic efficiency, with AUCs of 0.95 in the training cohort, 0.83 in the internal validation cohort, and 0.79 in the external validation cohort. The F-test indicated that the combined model exhibited a significantly superior AUC value compared to the radiomics model in the training cohort (P < 0.001). CONCLUSIONS: The combined model integrating clinical characteristics and radiomics features shows potential as a non-invasive adjunctive diagnostic modality for preoperative evaluation of the FIGO staging status of EOC, thereby facilitating clinical decision-making and enhancing patient outcomes.


Assuntos
Neoplasias Ovarianas , Radiômica , Feminino , Humanos , Algoritmos , Carcinoma Epitelial do Ovário/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/cirurgia , Tomografia Computadorizada por Raios X
13.
Artigo em Inglês | MEDLINE | ID: mdl-38747701

RESUMO

Two Gram-stain-negative strains, designed SYSU M86414T and SYSU M84420, were isolated from marine sediment samples of the South China Sea (Sansha City, Hainan Province, PR China). These strains were aerobic and could grow at pH 6.0-8.0 (optimum, pH 7.0), 4-37 °C (optimum, 28 °C), and in the presence of 0-10 % NaCl (w/v; optimum 3 %). The predominant respiratory menaquinone of strains SYSU M86414T and SYSU M84420 was MK-6. The primary cellular polar lipid was phosphatidylethanolamine. The major cellular fatty acids (>10 %) in both strains were iso-C15 : 0, iso-C15 : 1 G, and iso-C17 : 0 3-OH. The DNA G+C content of strains SYSU M86414T and SYSU M84420 were both 42.10 mol%. Phylogenetic analyses based on 16S rRNA gene sequences and core genes indicated that these novel strains belonged to the genus Flagellimonas and strain SYSU M86414T showed the highest 16S rRNA gene sequence similarity to Flagellimonas marinaquae JCM 11811T (98.83 %), followed by Flagellimonas aurea BC31-1-A7T (98.62 %), while strain SYSU M84420 had highest 16S rRNA gene sequence similarity to F. marinaquae JCM 11811T (98.76 %) and F. aurea BC31-1-A7T (98.55 %). Based on the results of polyphasic analyses, strains SYSU M86414T and SYSU M84420 should be considered to represent a novel species of the genus Flagellimonas, for which the name Flagellimonas halotolerans sp. nov. is proposed. The type strain of the proposed novel isolate is SYSU M86414T (=GDMCC 1.3806T=KCTC 102040T).


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Sedimentos Geológicos , Filogenia , RNA Ribossômico 16S , Água do Mar , Análise de Sequência de DNA , Vitamina K 2 , China , RNA Ribossômico 16S/genética , Sedimentos Geológicos/microbiologia , Ácidos Graxos/análise , Água do Mar/microbiologia , DNA Bacteriano/genética , Vitamina K 2/análogos & derivados , Vitamina K 2/análise , Fosfatidiletanolaminas , Dados de Sequência Molecular
14.
Artigo em Inglês | MEDLINE | ID: mdl-38530347

RESUMO

A Gram-stain-negative, non-endospore-forming, motile, short rod-shaped strain, designated SYSU G07232T, was isolated from a hot spring microbial mat, sampled from Rehai National Park, Tengchong, Yunnan Province, south-western China. Strain SYSU G07232T grew at 25-50 °C (optimum, 37 °C), at pH 5.5-9.0 (optimum, pH 6.0) and tolerated NaCl concentrations up to 1.0 % (w/v). Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain SYSU G07232T showed closest genetic affinity with Chelatococcus daeguensis K106T. The genomic features and taxonomic status of this strain were determined through whole-genome sequencing and a polyphasic approach. The predominant quinone of this strain was Q-10. Major cellular fatty acids comprised C19 : 0 cyclo ω8c and summed feature 8. The whole-genome length of strain SYSU G07232T was 4.02 Mbp, and the DNA G+C content was 69.26 mol%. The average nucleotide identity (ANIm ≤84.85 % and ANIb ≤76.08  %) and digital DNA-DNA hybridization (≤ 21.9 %) values between strain SYSU G07232T and the reference species were lower than the threshold values recommended for distinguishing novel prokaryotic species. Thus, based on the provided phenotypic, phylogenetic, and genetic data, it is proposed that strain SYSU G07232T (=KCTC 8141T=GDMCC 1.4178T) be designated as representing a novel species within the genus Chelatococcus, named Chelatococcus albus sp. nov.


Assuntos
Beijerinckiaceae , Fontes Termais , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , China , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias
15.
Fish Shellfish Immunol ; 150: 109662, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38821229

RESUMO

SIRT6, a key member of the sirtuin family, plays a pivotal role in regulating a number of vital biological processes, including energy metabolism, oxidative stress, and immune system modulation. Nevertheless, the function of SIRT6 in bony fish, particularly in the context of antiviral immune response, remains largely unexplored. In this study, a sirt6 was cloned and characterized in a commercial fish, the Chinese perch (Siniperca chuatsi). The SIRT6 possesses conserved SIR2 domain with catalytic core region when compared with other vertebrates. Tissue distribution analysis indicated that sirt6 was expressed in all detected tissues, and the sirt6 was significantly induced following infection of infectious haemorrhagic syndrome virus (IHSV). The overexpression of SIRT6 resulted in significant upregulation of interferon-stimulated genes (ISGs), such as viperin, mx, isg15, irf3 and ifp35, and inhibited viral replication. It was further found that SIRT6 was located in nucleus and could enhance the expression of ISGs induced by type I and II IFNs. These findings may provide new information in relation with the function of SIRT6 in vertebrates, and with viral prevention strategy development in aquaculture.


Assuntos
Sequência de Aminoácidos , Doenças dos Peixes , Proteínas de Peixes , Regulação da Expressão Gênica , Imunidade Inata , Percas , Filogenia , Infecções por Rhabdoviridae , Sirtuínas , Animais , Sirtuínas/genética , Sirtuínas/imunologia , Sirtuínas/metabolismo , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Proteínas de Peixes/química , Imunidade Inata/genética , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Regulação da Expressão Gênica/imunologia , Percas/imunologia , Alinhamento de Sequência/veterinária , Perfilação da Expressão Gênica/veterinária
16.
Fish Shellfish Immunol ; 146: 109402, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281613

RESUMO

Type II interferons (IFNs) are a key class of molecules regulating innate and adaptive immunity in vertebrates. In the present study, two members of the type II IFNs, IFN-γ and IFNγ-rel, were identified in the blunt snout bream (Megalobrama amblycephala). The open reading frame (ORF) of IFN-γ and IFNγ-rel was found to have 564 bp and 492 bp, encoding 187 and 163 amino acids, with the first 26 and 24 amino acids being the signal peptide, respectively. IFN-γ and IFNγ-rel genes showed a high degree of similarity to their zebrafish homologues, being 76.9 % and 58.9 %, respectively. In the phylogenetic tree, IFN-γ and IFNγ-rel were clustered with homologous genes in cyprinids. In blunt snout bream, IFN-γ and IFNγ-rel were constitutively expressed in trunk kidney, head kidney, spleen, liver, heart, muscle, gill, intestine and brain and were significantly up-regulated by poly (I:C) induction in head kidney, spleen, liver, gill and intestine. Using recombinant proteins of IFN-γ and IFNγ-rel, the surface plasmon resonance (SPR) results showed that IFN-γ was bound to CRFB6, CRFB13 and CRFB17, but mainly to CRFB6 and CRFB13, whereas IFN-γrel bound mainly to CRFB17 and had no affinity with CRFB6. These results contribute to a better understanding on type II IFNs and their receptor usage in teleost fish.


Assuntos
Cyprinidae , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Filogenia , Interferon gama/genética , Interferon gama/metabolismo , Sequência de Aminoácidos , Proteínas de Peixes/química , Proteínas Recombinantes/genética , Aminoácidos/genética
17.
J Immunol ; 209(10): 1918-1929, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36426956

RESUMO

Cyprinid herpesvirus 3 (CyHV-3) has caused severe economic losses to carp culture, but its pathogenicity is far from clear. Our previous study has revealed that microRNA (miR)-722 was upregulated during CyHV-3 infection, indicating that miR-722 might play an important role in CyHV-3 replication. In this study, we found that overexpression of miR-722 inhibited CyHV-3 replication and promoted IFN expression. The putative target gene of miR-722 was searched over the CyHV-3 genome, and ORF89 was identified and validated as a target gene of miR-722. Overexpression of ORF89 markedly reduced the expression of IFN and IFN-stimulated genes. Mechanistically, ORF89 interacted with and degraded IFN regulatory factor 3 (IRF3), and inhibited the entry of IRF3 into the nucleus by suppressing the dimerization of IRF3. Moreover, ORF89-mediated suppression of IFN expression could be restored by adding miR-722. To our knowledge, our findings confirm a novel virus-host combat, in which CyHV-3 evades host antiviral immunity by its ORF89 protein, whereas host miR-722, upregulated on CyHV-3 infection, targets ORF89 to impede CyHV-3 replication.


Assuntos
Evasão da Resposta Imune , MicroRNAs , Fator Regulador 3 de Interferon/genética , Proteínas Virais/genética , MicroRNAs/genética
18.
BMC Cardiovasc Disord ; 24(1): 75, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281972

RESUMO

BACKGROUND: This study aimed to uncover the changing prevalence of obesity and its association with hypertension across socioeconomic gradients in rural southwest China. METHODS: Data were collected from two cross-sectional health interviews and surveys from 2011 to 2021 among individuals aged ≥ 35 years in rural China. Each participant's height, weight, waist circumference, and blood pressure were measured. The overall prevalence of obesity, central obesity, and hypertension was directly standardized by age based on the total population of the two surveys. Multivariate logistic regression was used to analyze the association between obesity and prevalence of hypertension and an individual socioeconomic position (SEP) index was constructed using principal component analysis. RESULTS: From 2011 to 2021, the prevalence of obesity, central obesity, and hypertension increased substantially, from 5.9%, 50.2%, and 26.1-12.1%, 58.0%, and 40.4% (P < 0.01), respectively. These increasing rates existed in all subcategories, including sex, age, ethnicity, education, annual household income, access to medical services, and SEP (P < 0.05). In both 2011 and 2021, lower education level and poor access to medical services correlated with higher prevalence of central obesity, while higher SEP correlated with higher prevalence of obesity and central obesity (P < 0.01). Prevalence of obesity was higher in the Han ethnicity participants and individuals with poor access to medical services than in their counterparts (P < 0.01). Whereas the prevalence of central obesity was lower in Han participants than in ethnic minority participants in 2011 (P < 0.01), this trend reversed in 2021 (P < 0.01). A positive relationship between annual household income and prevalence of obesity and central obesity was only found in 2021 (P < 0.01). Obese and centrally obese participants were more likely to be hypertensive in both survey years (P < 0.01). CONCLUSIONS: Future interventions to prevent and manage obesity in rural China should give increased attention to high income, less educated, poor access to medical services, and high SEP individuals. The implementation of these obesity interventions would also help reduce the prevalence of hypertension.


Assuntos
Hipertensão , Obesidade Abdominal , Humanos , Obesidade Abdominal/diagnóstico , Obesidade Abdominal/epidemiologia , Etnicidade , Prevalência , Estudos Transversais , Grupos Minoritários , China/epidemiologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Obesidade/diagnóstico , Obesidade/epidemiologia , Escolaridade , População Rural , Fatores de Risco , Fatores Socioeconômicos
19.
Exp Cell Res ; 426(1): 113552, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36914061

RESUMO

It is recognized that the cerebral ischemia/reperfusion (I/R) injury triggers inflammatory activation of microglia and supports microglia-driven neuronal damage. Our previous studies have shown that ginsenoside Rg1 had a significant protective effect on focal cerebral I/R injury in middle cerebral artery occlusion (MCAO) rats. However, the mechanism still needs further clarification. Here, we firstly reported that ginsenoside Rg1 effectively suppressed the inflammatory activation of brain microglia cells under I/R conditions depending on the inhibition of Toll-likereceptor4 (TLR4) proteins. In vivo experiments showed that the ginsenoside Rg1 administration could significantly improve the cognitive function of MCAO rats, and in vitro experimental data showed that ginsenoside Rg1 significantly alleviated neuronal damage via inhibiting the inflammatory response in microglia cells co-cultured under oxygen and glucose deprivation/reoxygenation (OGD/R) condition in gradient dependent. The mechanism study showed that the effect of ginsenoside Rg1 depends on the suppression of TLR4/MyD88/NF-κB and TLR4/TRIF/IRF-3 pathways in microglia cells. In a word, our research shows that ginsenoside Rg1 has great application potential in attenuating the cerebral I/R injury by targeting TLR4 protein in the microglia cells.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Ratos , Animais , Microglia/metabolismo , Receptor 4 Toll-Like/metabolismo , Fármacos Neuroprotetores/farmacologia , Isquemia Encefálica/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo
20.
Environ Res ; 252(Pt 1): 118859, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574986

RESUMO

Electrocatalytic hydrodechlorination (EHDC) is a promising approach to safely remove halogenated emerging contaminants (HECs) pollutants. However, sluggish production dynamics of adsorbed atomic H (H*ads) limit the applicability of this green process. In this study, bimetallic Pd-Cu@MXene catalysts were synthesized to achieve highly efficient removal of HECs. The alloy electrode (Pd-Cu@MX/CC) exhibited better EHDC performance in comparison to Pd@MX/CC electrode, resulting in diclofenac degradation efficiency of 93.3 ± 0.1%. The characterization analysis revealed that the Pd0/PdII ratio decreased by forming bimetallic Pd-Cu alloy. Density functional theory calculations further demonstrated the electronic configuration modulation of the Pd-Cu@MXene catalysts, optimizing binging energies for H* and thereby facilitating H*ads production and tuning the reduction capability of H*ads. Noteably, the amounts and reduction potential of H*ads for Pd-Cu@MXene catalysts were 1.5 times higher and 0.37 eV lower than those observed for the mono Pd electrode. Hence, the introduction of Cu into the Pd catalyst optimized the dynamics of H*ads production, thereby conferring significant advantages to EHDC reactions. This augmentation was underscored by the successful application of the alloy catalysts supported by MXene in EHDC experiments involving other HECs, which represented a new paradigm for EHDC for efficient recalcitrant pollutant removal by H*ads.


Assuntos
Cobre , Paládio , Catálise , Cobre/química , Paládio/química , Poluentes Químicos da Água/química , Adsorção , Halogenação , Técnicas Eletroquímicas/métodos , Eletrodos , Diclofenaco/química
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