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1.
Mol Cell ; 84(11): 2104-2118.e6, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38761795

RESUMO

Circular RNAs (circRNAs) are stable RNAs present in cell-free RNA, which may comprise cellular debris and pathogen genomes. Here, we investigate the phenomenon and mechanism of cellular uptake and intracellular fate of exogenous circRNAs. Human myeloid cells and B cells selectively internalize extracellular circRNAs. Macrophage uptake of circRNA is rapid, energy dependent, and saturable. CircRNA uptake can lead to translation of encoded sequences and antigen presentation. The route of internalization influences immune activation after circRNA uptake, with distinct gene expression programs depending on the route of RNA delivery. Genome-scale CRISPR screens and chemical inhibitor studies nominate macrophage scavenger receptor MSR1, Toll-like receptors, and mTOR signaling as key regulators of receptor-mediated phagocytosis of circRNAs, a dominant pathway to internalize circRNAs in parallel to macropinocytosis. These results suggest that cell-free circRNA serves as an "eat me" signal and danger-associated molecular pattern, indicating orderly pathways of recognition and disposal.


Assuntos
Macrófagos , Fagocitose , RNA Circular , Transdução de Sinais , RNA Circular/genética , RNA Circular/metabolismo , Humanos , Macrófagos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Animais , Receptores Toll-Like/metabolismo , Receptores Toll-Like/genética , Linfócitos B/metabolismo , Linfócitos B/imunologia , Receptores Depuradores Classe A/metabolismo , Receptores Depuradores Classe A/genética , Apresentação de Antígeno , Pinocitose , Camundongos
2.
PLoS Pathog ; 20(5): e1012215, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38701108

RESUMO

Fusarium head blight (FHB), caused by Fusarium graminearum species complexes (FGSG), is an epidemic disease in wheat and poses a serious threat to wheat production and security worldwide. Profilins are a class of actin-binding proteins that participate in actin depolymerization. However, the roles of profilins in plant fungal pathogens remain largely unexplored. Here, we identified FgPfn, a homolog to profilins in F. graminearum, and the deletion of FgPfn resulted in severe defects in mycelial growth, conidia production, and pathogenicity, accompanied by marked disruptions in toxisomes formation and deoxynivalenol (DON) transport, while sexual development was aborted. Additionally, FgPfn interacted with Fgα1 and Fgß2, the significant components of microtubules. The organization of microtubules in the ΔFgPfn was strongly inhibited under the treatment of 0.4 µg/mL carbendazim, a well-known group of tubulin interferers, resulting in increased sensitivity to carbendazim. Moreover, FgPfn interacted with both myosin-5 (FgMyo5) and actin (FgAct), the targets of the fungicide phenamacril, and these interactions were reduced after phenamacril treatment. The deletion of FgPfn disrupted the normal organization of FgMyo5 and FgAct cytoskeleton, weakened the interaction between FgMyo5 and FgAct, and resulting in increased sensitivity to phenamacril. The core region of the interaction between FgPfn and FgAct was investigated, revealing that the integrity of both proteins was necessary for their interaction. Furthermore, mutations in R72, R77, R86, G91, I101, A112, G113, and D124 caused the non-interaction between FgPfn and FgAct. The R86K, I101E, and D124E mutants in FgPfn resulted in severe defects in actin organization, development, and pathogenicity. Taken together, this study revealed the role of FgPfn-dependent cytoskeleton in development, DON production and transport, fungicides sensitivity in F. graminearum.


Assuntos
Actinas , Proteínas Fúngicas , Fungicidas Industriais , Fusarium , Microtúbulos , Doenças das Plantas , Triticum , Microtúbulos/metabolismo , Fusarium/metabolismo , Fusarium/patogenicidade , Fusarium/genética , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Actinas/metabolismo , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Triticum/microbiologia , Fungicidas Industriais/farmacologia , Esporos Fúngicos/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Reprodução
3.
Cell ; 142(5): 699-713, 2010 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-20813259

RESUMO

Monoclonal antibodies are standard therapeutics for several cancers including the anti-CD20 antibody rituximab for B cell non-Hodgkin lymphoma (NHL). Rituximab and other antibodies are not curative and must be combined with cytotoxic chemotherapy for clinical benefit. Here we report the eradication of human NHL solely with a monoclonal antibody therapy combining rituximab with a blocking anti-CD47 antibody. We identified increased expression of CD47 on human NHL cells and determined that higher CD47 expression independently predicted adverse clinical outcomes in multiple NHL subtypes. Blocking anti-CD47 antibodies preferentially enabled phagocytosis of NHL cells and synergized with rituximab. Treatment of human NHL-engrafted mice with anti-CD47 antibody reduced lymphoma burden and improved survival, while combination treatment with rituximab led to elimination of lymphoma and cure. These antibodies synergized through a mechanism combining Fc receptor (FcR)-dependent and FcR-independent stimulation of phagocytosis that might be applicable to many other cancers.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígeno CD47/imunologia , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/terapia , Fagocitose , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Murinos , Linfócitos B/imunologia , Linhagem Celular Tumoral , Humanos , Linfoma não Hodgkin/diagnóstico , Camundongos , Receptores Fc/imunologia , Rituximab , Ensaios Antitumorais Modelo de Xenoenxerto
4.
FASEB J ; 37(8): e23084, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37410073

RESUMO

Spermatogenesis is a highly organized process by which undifferentiated spermatogonia self-renew and differentiate into spermatocytes and spermatids. The entire developmental process from spermatogonia to sperm occurs within the seminiferous tubules. Spermatogenesis is supported by the close interaction of germ cells with Sertoli cells. In this study, testicular tissues were collected from Hu sheep at 8 timepoints after birth: 0, 30, 90, 180, 270, 360, 540, and 720 days. Immunofluorescence staining and histological analysis were used to explore the development of male germ cells and Sertoli cells in the Hu sheep testes at these timepoints. The changes in seminiferous tubule diameter and male germ cells in the Hu sheep testes at these different developmental stages were analyzed. Then, specific molecular markers were used to study the proliferation and differentiation of spermatogonia, the timepoint of spermatocyte appearance, and the maturation and proliferation of Sertoli cells in the seminiferous tubules. Finally, the formation of the blood-testes barrier was studied using antibodies against the main components of the blood-testes barrier, ß-catenin, and ZO-1. These findings not only increased the understanding of the development of the Hu sheep testes, but also laid a solid theoretical foundation for Hu sheep breeding.


Assuntos
Células de Sertoli , Testículo , Masculino , Animais , Ovinos , Sêmen , Espermatogênese , Espermatogônias
5.
Plant Dis ; 108(3): 658-665, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37773329

RESUMO

Gummy stem blight, caused by Didymella bryoniae, is an important disease in watermelon in China. Fluxapyroxad, a new succinate dehydrogenase inhibitor fungicide, shows strong inhibition of the mycelia growth of D. bryoniae. However, its resistance risk in D. bryoniae is unclear. In this research, the sensitivities of 60 D. bryoniae strains to fluxapyroxad were investigated. The average EC50 value and MIC values of 60 D. bryoniae strains against fluxapyroxad were 0.022 ± 0.003 µg/ml and ≤0.1 µg/ml for mycelial growth, respectively. Eight fluxapyroxad-resistant mutants with medium resistance levels were acquired from three wild-type parental strains. The mycelial growth and dry weight of mycelia of most mutants were significantly lower than those of their parental strains. However, four resistant mutants showed a similar phenotype in pathogenicity compared with their parental strains. The above results demonstrated that there was a medium resistance risk for fluxapyroxad in D. bryoniae. The cross-resistance assay showed that there was positive cross-resistance between fluxapyroxad and pydiflumetofen, thifluzamide, and boscalid, but there was no cross-resistance between fluxapyroxad and tebuconazole and mepronil. These results will contribute to evaluating the resistance risk of fluxapyroxad for managing diseases caused by D. bryoniae and further increase our understanding about the mode of action of fluxapyroxad.


Assuntos
Ascomicetos , Fungicidas Industriais , Fungicidas Industriais/farmacologia , Ascomicetos/fisiologia , Amidas
6.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397028

RESUMO

The emergence of plasmid-mediated colistin resistance threatens the efficacy of colistin as a last-resort antibiotic used to treat infection caused by Gram-negative bacteria (GNB). Given the shortage of new antibiotics, the discovery of adjuvants to existing antibiotics is a promising strategy to combat infections caused by multidrug-resistant (MDR) GNB. This study was designed to investigate the potential synergistic antibacterial activity of bavachin, a bioactive compound extracted from the Psoralea Fructus, combined with colistin against MDR GNB. Herein, the synergistic efficacy in vitro and the therapeutic efficacy of colistin combined with bavachin in vivo were evaluated. The synergistic mechanism was detected by fluorescent probe and the transcript levels of mcr-1. Bavachin combined with colistin showed an excellent synergistic activity against GNB, as the FICI ≤ 0.5. In contrast to colistin alone, combination therapy dramatically increased the survival rate of Galleria mellonella and mice in vivo. Moreover, the combination of bavachin and colistin significantly reduced the amount of bacterial biofilm formation, improved the membrane disruption of colistin and inhibited mcr-1 transcription. These findings show that bavachin is a potential adjuvant of colistin, which may provide a new strategy to combat colistin-resistant bacteria infection with lower doses of colistin.


Assuntos
Antibacterianos , Colistina , Animais , Camundongos , Colistina/farmacologia , Antibacterianos/farmacologia , Flavonoides/farmacologia , Bactérias Gram-Negativas , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana
7.
J Environ Manage ; 360: 121217, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788411

RESUMO

With rapid economic growth, the issue of water pollution has become increasingly prominent, and there is a consensus that river basin management systems and cross-regional management coordination mechanisms need improving. In this study, 171 transboundary sections of the Yangtze River Basin were matched with the data of 57 cities to construct panel data from 2015 to 2021. Based on the four-dimensional framework of environment-determination-process-resources, the dynamic qualitative comparative analysis (QCA) method is used to identify the key influencing factors and action paths of water pollution collaborative governance effects. The results show that a single antecedent condition is not necessary to achieve efficient collaborative governance effects, and only the "number of collaborative governance" and "scale of collaboration" conditions played important roles. There are five paths that can achieve efficient collaborative governance effects: economy-oriented, ecology-oriented, technology-oriented, government-oriented, and all-oriented. Additionally, heterogeneous results show that the impact of the regional governance intention on efficient collaborative governance effect is limited in the middle and upstream sections of the Yangtze River Basin, while the downstream sections are more dependent on the basic condition of the basin. The results can help promote effective cross-regional collaboration in the Yangtze River Basin, provide scientific basis for regions to formulate targeted governance measures, and provide models for governance in other regions.


Assuntos
Rios , Poluição da Água , China , Poluição da Água/prevenção & controle , Conservação dos Recursos Naturais
8.
J Obstet Gynaecol ; 44(1): 2317387, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38466132

RESUMO

BACKGROUND: Cervical cancer survivors can experience vaginal length shortening, vaginal stenosis, vaginal elasticity deterioration, sexual frequency reduction and sexual dysfunction. This prospective, uncontrolled, monocentric clinical interventional study aimed to evaluate the effect of vaginal dilation therapy on vaginal condition and sexual function of cervical cancer survivors who had not received timely vaginal dilation. METHODS: A total of 139 patients completed the study. They received 6 months of vaginal dilation therapy. We evaluated their vaginal elasticity, vaginal diameter, vaginal length and sexual function before and after vaginal dilation therapy. Their vaginal conditions were evaluated by customised vaginal moulds, and the sexual function was assessed by female sexual function index. The SPSS 25 software was used to analyse all the data. RESULTS: Age, vaginal diameter and sexual intercourse frequency before diagnosis were significantly associated with female sexual dysfunction of the patients after cancer treatment. Vaginal dilation therapy improved vaginal stenosis, vaginal length and sexual function in all the patients; however, the vaginal elasticity and incidence of sexual dysfunction did not improve significantly. Sexual intercourse frequency before diagnosis, vaginal elasticity, time interval from last treatment and treatment modalities were significantly associated with the change in female sexual function index score before and after vaginal dilation therapy. Patients with a time interval from the last treatment less than 24 months or those who had moderate or good vaginal elasticity, benefitted more from vaginal dilatation therapy. CONCLUSIONS: Cervical cancer survivors who had not received timely vaginal dilation still benefitted from vaginal dilation therapy, irrespective of the treatment methods they received. Moreover, vaginal dilation therapy should be performed as early as possible after cervical cancer treatment.


Cervical cancer survivors can experience vaginal condition deterioration and sexual dysfunction after treatment. Vaginal dilation can help improve vaginal stenosis, vaginal length and sexual function of these patients. However, some medical institutions in China do not provide timely vaginal dilation for this population. This study aimed to explore whether vaginal dilation was still effective for cervical cancer survivors who had not received timely vaginal dilation. The results showed that these patients still benefitted from vaginal dilation, irrespective of the treatment methods they received. Patients with a time interval from the last treatment less than 24 months or those who had moderate or good vaginal elasticity, benefitted more from vaginal dilation. The findings of the study is an indication to developing countries that more attention should be given to sexual issue of cervical cancer survivors in clinical practice, and vaginal dilation therapy should be performed promptly after treatment.


Assuntos
Sobreviventes de Câncer , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/terapia , Vagina , Constrição Patológica/etiologia , Constrição Patológica/terapia , Dilatação/efeitos adversos , Estudos Prospectivos , Elasticidade
9.
PLoS Med ; 20(6): e1004233, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37339120

RESUMO

BACKGROUND: Klebsiella pneumoniae is the most common pathogen causing neonatal infections, leading to high mortality worldwide. Along with increasing antimicrobial use in neonates, carbapenem-resistant K. pneumoniae (CRKP) has emerged as a severe challenge for infection control and treatment. However, no comprehensive systematic review is available to describe the global epidemiology of neonatal CRKP infections. We therefore performed a systematic review of available data worldwide and combined a genome-based analysis to address the prevalence, clonal diversity, and carbapenem resistance genes of CRKP causing neonatal infections. METHODS AND FINDINGS: We performed a systematic review of studies reporting population-based neonatal infections caused by CRKP in combination with a genome-based analysis of all publicly available CRKP genomes with neonatal origins. We searched multiple databases (PubMed, Web of Science, Embase, Ovid MEDLINE, Cochrane, bioRxiv, and medRxiv) to identify studies that have reported data of neonatal CRKP infections up to June 30, 2022. We included studies addressing the prevalence of CRKP infections and colonization in neonates but excluded studies lacking the numbers of neonates, the geographical location, or independent data on Klebsiella or CRKP isolates. We used narrative synthesis for pooling data with JMP statistical software. We identified 8,558 articles and excluding those that did not meet inclusion criteria. We included 128 studies, none of which were preprints, comprising 127,583 neonates in 30 countries including 21 low- and middle-income countries (LMICs) for analysis. We found that bloodstream infection is the most common infection type in reported data. We estimated that the pooled global prevalence of CRKP infections in hospitalized neonates was 0.3% (95% confidence interval [CI], 0.2% to 0.3%). Based on 21 studies reporting patient outcomes, we found that the pooled mortality of neonatal CRKP infections was 22.9% (95% CI, 13.0% to 32.9%). A total of 535 neonatal CRKP genomes were identified from GenBank including Sequence Read Archive, of which 204 were not linked to any publications. We incorporated the 204 genomes with a literature review for understanding the species distribution, clonal diversity, and carbapenemase types. We identified 146 sequence types (STs) for neonatal CRKP strains and found that ST17, ST11, and ST15 were the 3 most common lineages. In particular, ST17 CRKP has been seen in neonates in 8 countries across 4 continents. The vast majority (75.3%) of the 1,592 neonatal CRKP strains available for analyzing carbapenemase have genes encoding metallo-ß-lactamases and NDM (New Delhi metallo-ß-lactamase) appeared to be the most common carbapenemase (64.3%). The main limitation of this study is the absence or scarcity of data from North America, South America, and Oceania. CONCLUSIONS: CRKP contributes to a considerable number of neonatal infections and leads to significant neonatal mortality. Neonatal CRKP strains are highly diverse, while ST17 is globally prevalent and merits early detection for treatment and prevention. The dominance of blaNDM carbapenemase genes imposes challenges on therapeutic options in neonates and supports the continued inhibitor-related drug discovery.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Doenças Transmissíveis , Infecções por Klebsiella , Recém-Nascido , Humanos , Klebsiella pneumoniae/genética , Prevalência , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico
10.
Biochem Biophys Res Commun ; 645: 61-70, 2023 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-36680938

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a common malignancy with high morbidity and mortality. Although circular RNAs (circRNAs) play important roles in various cancers including ESCC, the role of the circRNA mannosidase alpha class 1A member 2 (circMAN1A2) in ESCC has been rarely studied. This study aimed to explore the role of circMAN1A2 in ESCC. CircMAN1A2 expression in ESCC tissues and cells was evaluated, and the relationship between circMAN1A2 expression and prognosis in patients with ESCC was analyzed. C-C chemokine ligand 5 (CCL5) was found to be a downstream target of circMAN1A2 by analysing the Agilent Microarray. Next, we performed in vitro and in vivo xenotransplantation assays to explore the role of circMAN1A2 in ESCC. We observed that high circMAN1A2 expression is associated with poor prognosis in patients with ESCC. Suppression of circMAN1A2 expression inhibits the proliferation, migration, and invasiveness of ESCC via regulating CCL5. Our results suggest that circMAN1A2 can promote the progression of ESCC by regulating CCL5. Thus, circMAN1A2 might be a novel diagnostic biomarker of ESCC, and targeting circMAN1A2 using inhibitors could be a potential therapeutic strategy to treat ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Humanos , Carcinoma de Células Escamosas do Esôfago/patologia , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias Esofágicas/patologia , Ligantes , Manosidases/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética
11.
Appl Environ Microbiol ; 89(7): e0056123, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37404138

RESUMO

Vibrio cholerae is the causative agent of cholera. Effective intestinal colonization is a key step for V. cholerae pathogenicity and transmission. In this study, we found that deleting mshH, a homolog of the Escherichia coli CsrD protein, caused a V. cholerae colonization defect in the intestine of adult mice. By analyzing the RNA levels of CsrB, CsrC, and CsrD, we found that deleting mshH increased the levels of CsrB and CsrD but decreased the level of CsrC. However, deleting CsrB and -D not only recovered the mshH deletion mutant colonization defect but also recovered CsrC to wild-type levels. These results indicated that controlling the RNA levels of CsrB, -C, and -D is crucial for V. cholerae colonization of adult mice. We further demonstrated that the RNA levels of CsrB and CsrD were mainly controlled by MshH-dependent degradation, yet the level of CsrC was mainly determined by the CsrA-dependent stabilization. Our data show that V. cholerae differentially controls CsrB, -C, and -D abundance through the MshH-CsrB/C/D-CsrA regulatory pathway to finely regulate the activity of CsrA targets such as ToxR, so as to better survive in adult mouse intestine. IMPORTANCE The ability of V. cholerae to colonize the intestine is a key factor for its fitness and transmissibility between hosts. Here, we investigated the mechanism of V. cholerae colonization of adult mammal intestine and found that precisely controlling the CsrB, -C, and -D contents by MshH and CsrA plays an essential role for V. cholerae colonization in the adult mouse intestine. These data expand our knowledge on the mechanism of V. cholerae controlling the RNA level of CsrB, -C, and -D and highlight the importance that the different strategies used by V. cholerae to regulate the RNA level of CsrB, -C, and -D confer the bacterium with a survival advantage.


Assuntos
Cólera , Proteínas de Escherichia coli , RNA Longo não Codificante , Vibrio cholerae , Animais , Camundongos , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Proteínas Repressoras/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Bacteriano/metabolismo , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mamíferos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Escherichia coli/genética
12.
FASEB J ; 36(11): e22605, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36250963

RESUMO

Upon chronic damage to the liver, multiple cytokines stimulate hepatic stellate cells (HSCs), causing the alterations of gene expression profiles and thus leading to HSC activation, a key step in liver fibrogenesis. Activated HSCs are the dominant contributors to liver fibrosis. Bromodomain containing protein 4 (BrD4), an important epigenetic reader, was demonstrated to concentrate on hundreds of enhancers associated with genes involved in multiple profibrotic pathways, thereby directing HSC activation and the fibrotic responses. The present studies were designed to examine the effect of transforming growth factor beta-1 (TGFß1), the most potent pro-fibrotic cytokine, on BrD4 expression in HSCs and, if so, elucidated the underlying mechanisms in vitro and in vivo. The experiments employed the heterogeneous TGFß1 knockout (TGFß1+/- ) mice, gene knockdown in vivo, and a model of thioacetamide (TAA)-induced liver injury. The results revealed that TGFß1 enhanced BrD4 expression in HSCs, which was mediated, at least, by Smad3 signaling and early-immediate gene Egr1 (early growth response-1). TGFß1-induced Smad3 signaling increased Egr1 expression and promoted Egr1 binding to BrD4 promoter at a site around -111 bp, promoting BrD4 expression. Egr1 knockdown reduced BrD4 expression in HSCs in a mouse model of TAA-induced liver injury and lessened liver fibrosis. Double fluorescence staining demonstrated a strong increase in BrD4 expression in activated HSCs in fibrotic areas of the human livers, paralleling the upregulation of p-Smad3 and Egr1. This research suggested novel molecular events underlying the roles of the master pro-fibrotic cytokine TGFß1 in HSC activation and liver fibrogenesis.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Proteína 1 de Resposta de Crescimento Precoce , Células Estreladas do Fígado , Proteínas Nucleares , Fatores de Transcrição , Animais , Humanos , Camundongos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Epigênese Genética , Fibrose , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Proteínas Nucleares/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Tioacetamida/efeitos adversos , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
13.
Int J Mol Sci ; 24(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762514

RESUMO

Streptococcus suis is an emerging zoonotic pathogen that can cause fatal diseases such as meningitis and sepsis in pigs and human beings. The overuse of antibiotics is leading to an increased level of resistance in S. suis, and novel antimicrobial agents or anti-virulence agents for the treatment of infections caused by S. suis are urgently needed. In the present study, we investigated the antibacterial activity, mode of action and anti-virulence effects of floxuridine against S. suis. Floxuridine showed excessive antibacterial activity against S. suis both in vivo and in vitro; 4 × MIC of floxuridine could kill S. suis within 8 h in a time-kill assay. Meanwhile, floxuridine disrupted the membrane structure and permeability of the cytoplasmic membrane. Molecular docking revealed that floxuridine and SLY can be directly bind to each other. Moreover, floxuridine effectively inhibited the hemolytic capacity and expression levels of the virulence-related genes of S. suis. Collectively, these results indicate that the FDA-approved anticancer drug floxuridine is a promising agent and a potential virulence inhibitor against S. suis.

14.
Int J Mol Sci ; 24(8)2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-37108521

RESUMO

Streptococcus suis, an encapsulated zoonotic pathogen, has been reported to cause a variety of infectious diseases, such as meningitis and streptococcal-toxic-shock-like syndrome. Increasing antimicrobial resistance has triggered the need for new treatments. In the present study, we found that isopropoxy benzene guanidine (IBG) significantly attenuated the effects caused by S. suis infection, in vivo and in vitro, by killing S. suis and reducing S. suis pathogenicity. Further studies showed that IBG disrupted the integrity of S. suis cell membranes and increased the permeability of S. suis cell membranes, leading to an imbalance in proton motive force and the accumulation of intracellular ATP. Meanwhile, IBG antagonized the hemolysis activity of suilysin and decreased the expression of Sly gene. In vivo, IBG improved the viability of S. suis SS3-infected mice by reducing tissue bacterial load. In conclusion, IBG is a promising compound for the treatment of S. suis infections, given its antibacterial and anti-hemolysis activity.


Assuntos
Infecções Estreptocócicas , Streptococcus suis , Animais , Camundongos , Streptococcus suis/genética , Benzeno , Guanidina , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Guanidinas/farmacologia , Guanidinas/uso terapêutico , Guanidinas/metabolismo , Proteínas Hemolisinas/metabolismo
15.
Environ Monit Assess ; 195(9): 1133, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656251

RESUMO

In the process of urbanization, exploring the relationship between production-living-ecological space (PLES) and ecosystem service value (ESV) is a major scientific issue in promoting regional sustainable development. The Yangtze River Delta (YRD) urban agglomeration is an ideal study area, which has the highest urbanization rate in China. Based on Landsat TM/ETM imaging data from 2005, 2010, 2015, and 2018, this study established a land use classification system of PLES. The spatial and temporal characteristics of PLES and ESV were analyzed, and the response of ESV to changes in PLES was investigated based on the elasticity formula. The results showed that from 2005 to 2018, production space and ecological space were the main types of PLES and exhibited an imbalance in transformation. Production space was the main transfer type, and living space significantly expanded. Moreover, from 2005 to 2018, the ESV of the YRD urban agglomeration showed an increasing and then decreasing trend. ESV presented a "high in the southwest and low in the northeast" spatial pattern. Furthermore, ESV was sensitive to changes in PLES, showing a trend of ecological space > production space > living space. However, the sensitivity of ESV to changes in PLES varied according to urbanization level.


Assuntos
Ecossistema , Rios , Monitoramento Ambiental , China , Elasticidade
16.
Appl Environ Microbiol ; 88(8): e0007222, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35384706

RESUMO

Vibrio cholerae is the causative agent of cholera, a life-threatening diarrheal disease in humans. The ability of V. cholerae to colonize the intestine of different animals is a key factor for its fitness and transmissibility between hosts. Many virulence factors, including the ToxT regulon, have been identified to be the major components allowing V. cholerae to colonize the small intestine of suckling mice; however, the mechanism of V. cholerae colonization in the adult mammalian intestine is unclear. In this study, using the streptomycin-treated adult mouse animal model, we characterized the role of the ToxT regulon in V. cholerae colonization in adult mammalian intestine. We first found that the activity of TcpP regulating ToxT regulon expression was attenuated by intestinal reactive oxygen species (ROS). We then found that V. cholerae containing a deletion of the ToxT regulon showed a competition advantage in colonizing adult mice; however, a mutant containing a constitutively active ToxT regulon showed a significant defect in colonizing adult mice. Constitutively producing the virulence factors in the ToxT regulon causes a V. cholerae competition defect in nutrient-limiting conditions. The results of this study demonstrate that modulating the activity of the ToxT regulon through ROS sensed by TcpP is critical for V. cholerae to enhance its colonization in the intestine of adult mice. IMPORTANCE Vibrio cholerae can inhabit both marine and freshwater ecosystems and can also enter and proliferate in the intestine of different animals which consume contaminated food or water. To successfully colonize the intestines of different hosts, V. cholerae coordinates its gene expression in response to different environments. Here, we describe how V. cholerae modulates the activity of the ToxT regulon by TcpP sensing ROS signals in the intestine of adult mice to better survive in this environment. We found that the constitutively active ToxT regulon causes V. cholerae growth retardation and colonization defect in adult mice. Our work highlights the distinctive role that regulating the activity of the ToxT regulon plays for V. cholerae to achieve full survival fitness in the adult mammalian intestine.


Assuntos
Vibrio cholerae , Animais , Proteínas de Bactérias/metabolismo , Ecossistema , Mamíferos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Regulon , Fatores de Transcrição/metabolismo , Vibrio cholerae/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
17.
Phytopathology ; 112(2): 290-298, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34156266

RESUMO

In agriculture, Trehalase is considered the main target of the biological fungicide validamycin A, and the toxicology mechanism of validamycin A is unknown. 14-3-3 proteins, highly conserved proteins, participate in diverse cellular processes, including enzyme activation, protein localization, and acting as a molecular chaperone. In Saccharomyces cerevisiae, the 14-3-3 protein Bmh1could interact with Nth1 to respond to specific external stimuli. Here, we characterized FgNth, FgBmh1, and FgBmh2 in Fusarium graminearum. ΔFgNth, ΔFgBmh1, and ΔFgBmh2 displayed great growth defects and their peripheral tips hyphae generated more branches when compared with wild-type (WT) PH-1. When exposed to validamycin A as well as high osmotic and high temperature stresses, ΔFgNth, ΔFgBmh1, and ΔFgBmh2 showed more tolerance than WT. Both ΔFgNth and ΔFgBmh1 displayed reduced deoxynivalenol production but opposite for ΔFgBmh2, and all three deletion mutants showed reduced virulence on wheat coleoptiles. In addition, coimmunoprecipitation (Co-IP) experiments suggested that FgBmh1 and FgBmh2 both interact with FgNth, but no interaction was detected between FgBmh1 and FgBmh2 in our experiments. Further, validamycin A enhances the interaction between FgBmh1 and FgNth in a positive correlation under concentrations of 1 to 100 µg/ml. In addition, both high osmotic and high temperature stresses promote the interaction between FgBmh1 and FgNth. Co-IP assay also showed that neither FgBmh1 nor FgBmh2 could interact with FgPbs2, a MAPKK kinase in the high-osmolarity glycerol pathway. However, FgBmh2 but not FgBmh1 binds to the heat shock protein FgHsp70 in F. graminearum. Taken together, our results demonstrate that FgNth and FgBmh proteins are involved in growth and responses to external stresses and virulence; and validamycin enhanced the interaction between FgNth and FgBmh1in F. graminearum.


Assuntos
Proteínas 14-3-3 , Fusarium , Proteínas 14-3-3/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Inositol/análogos & derivados , Doenças das Plantas , Trealase/genética , Trealase/metabolismo
18.
Tohoku J Exp Med ; 258(1): 43-48, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35793945

RESUMO

Amyloidosis is characterized by systemic or local deposition of amyloid fibrils outside organs and tissues. Amyloidosis is rarely seen on cornea. A 30-year-old woman patient had had trichiasis in both eyes for 8 years. Trichiasis was observed, which touched the cornea. Slit lamp microscopy showed white gelatinous droplet-like eminences and trichiasis in the lower cornea of the right eye. Optical coherence tomography showed that the lesion involved most of the cornea. Hematoxylin and eosin staining showed that most of the stroma stained red, with scattered inflammatory cells. High expression of lactoferrin was detected by mass spectrometry, and the case was diagnosed as secondary corneal lactoferrin amyloidosis in the right eye.


Assuntos
Amiloidose , Distrofias Hereditárias da Córnea , Pestanas , Triquíase , Adulto , Amiloidose/complicações , Amiloidose/diagnóstico por imagem , Amiloidose Familiar , Biópsia/efeitos adversos , Córnea/metabolismo , Córnea/patologia , Distrofias Hereditárias da Córnea/complicações , Pestanas/metabolismo , Pestanas/patologia , Feminino , Humanos , Lactoferrina , Espectrometria de Massas , Triquíase/complicações
19.
Pestic Biochem Physiol ; 188: 105253, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36464359

RESUMO

Fusarium graminearum is an important plant pathogen and the causal agent of Fusarium head blight (FHB). At present, the principal method of controlling FHB is through fungicides. Fluazinam is an agent with strong broad-spectrum antifungal activity and has been used to control many diseases. However, there are no reported uses of fluazinam for controlling FHB. This study reports the activity and cell toxicology mechanisms of fluazinam on the filamentous fungus F. graminearum and its effect on fungal growth and development. The activity of fluazinam was tested for 95 wild-type field strains of F. graminearum. The EC50 values (the 50% effective concentration) of fluazinam for inhibition of mycelial growth and spore germination ranged from 0.037 µg/ml to 0.179 µg/ml and from 0.039 µg/ml to 0.506 µg/ml, respectively. The fluazinam sensitivity of these strains varied in 4.9 and 13.0 folds, implying that the target of the fungicide remained unchanged. After treatment with 0.3 µg/ml (≈EC90) fluazinam, the production of conidia was reduced, and the cell wall and cell membrane had shrunked; the cell nucleus and septum morphology, cell membrane permeability, and sexual development were not affected. When treated with 0.1 µg/ml (≈EC50) or 0.3 µg/ml fluazinam, the mycelial respiration and deoxynivalenol (DON) synthesis of F. graminearum were decreased. Confocal images showed that the formation of toxisomes was disturbed after fluazinam treatment, suggesting that fluazinam reduces DON synthesis by inhibiting toxisome formation. Infection of wheat coleoptiles revealed that fluazinam had a strong protective activity against F. graminearum. At 250 µg/ml fluazinam the control efficacy of protective treatments reached 100% and controlled strains resistant to carbendazim. These results contribute to the understanding of the mode of action of fluazinam and its application.


Assuntos
Fungicidas Industriais , Fusarium , Aminopiridinas , Fungicidas Industriais/toxicidade
20.
Nano Lett ; 21(18): 7715-7723, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34491070

RESUMO

Seeded lithium (Li) nucleation has been considered as a promising strategy to achieve uniform Li deposition. However, problems of agglomeration and pulverization quickly invalidate the nucleation seeds, resulting in Li dendrite growth during repeated charge/discharge processes. Herein, liquid gallium-indium (GaIn) nanoparticles with structural self-healing properties are utilized to guide uniform metallic Li nucleation and deposition. Ultrafine GaIn nanoparticles (∼25 nm) uniformly decorated on the surface of carbon layers effectively homogenize the lithium-ion flux. After fully Li stripping, lithiophilic GaIn nanoparticles return to the liquid binary eutectic phase, thereby healing the deformed structure and enabling them to continuously guide dendrite-free Li deposition. Li metal anodes with such nucleation seeds exhibit nearly zero nucleation overpotential even after hundreds of cycles and a high average Coulombic efficiency of 99.03% for more than 400 cycles. The design of self-healing nucleation seeds provides important insights for obtaining high-performance lithium metal anodes.

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