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Experimental monoclonal antibody (mAb) therapies have shown promise for treatment of lethal Ebola virus (EBOV) infections, but their species-specific recognition of the viral glycoprotein (GP) has limited their use against other divergent ebolaviruses associated with human disease. Here, we mined the human immune response to natural EBOV infection and identified mAbs with exceptionally potent pan-ebolavirus neutralizing activity and protective efficacy against three virulent ebolaviruses. These mAbs recognize an inter-protomer epitope in the GP fusion loop, a critical and conserved element of the viral membrane fusion machinery, and neutralize viral entry by targeting a proteolytically primed, fusion-competent GP intermediate (GPCL) generated in host cell endosomes. Only a few somatic hypermutations are required for broad antiviral activity, and germline-approximating variants display enhanced GPCL recognition, suggesting that such antibodies could be elicited more efficiently with suitably optimized GP immunogens. Our findings inform the development of both broadly effective immunotherapeutics and vaccines against filoviruses.
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Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Vacinas contra Ebola/imunologia , Doença pelo Vírus Ebola/imunologia , Sobreviventes , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Chlorocebus aethiops , Reações Cruzadas , Ebolavirus/classificação , Ebolavirus/imunologia , Feminino , Furões , Doença pelo Vírus Ebola/virologia , Humanos , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Alinhamento de Sequência , Células VeroRESUMO
Necrotrophic fungal plant pathogens employ cell death-inducing proteins (CDIPs) to facilitate infection. However, the specific CDIPs and their mechanisms in pathogenic processes of Sclerotinia sclerotiorum, a necrotrophic pathogen that causes disease in many economically important crop species, have not yet been clearly defined. This study found that S. sclerotiorum secretes SsXyl2, a glycosyl hydrolase family 11 xylanase, at the late stage of hyphal infection. SsXyl2 targets the apoplast of host plants to induce cell death independent of xylanase activity. Targeted disruption of SsXyl2 leads to serious impairment of virulence, which can be recovered by a catalytically impaired SsXyl2 variant, thus supporting the critical role of cell death-inducing activity of SsXyl2 in establishing successful colonization of S. sclerotiorum. Remarkably, infection by S. sclerotiorum induces the accumulation of Nicotiana benthamiana hypersensitive-induced reaction protein 2 (NbHIR2). NbHIR2 interacts with SsXyl2 at the plasma membrane and promotes its localization to the cell membrane and cell death-inducing activity. Furthermore, gene-edited mutants of NbHIR2 displayed increased resistance to the wild-type strain of S. sclerotiorum, but not to the SsXyl2-deletion strain. Hence, SsXyl2 acts as a CDIP that manipulates host cell physiology by interacting with hypersensitive induced reaction protein to facilitate colonization by S. sclerotiorum. These findings provide valuable insights into the pathogenic mechanisms of CDIPs in necrotrophic pathogens and lead to a more promising approach for breeding resistant crops against S. sclerotiorum.
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Ascomicetos , Melhoramento Vegetal , Plantas , Virulência , Nicotiana , Morte Celular , Doenças das Plantas/microbiologiaRESUMO
Th17 cells have been investigated in mice primarily for their contributions to autoimmune diseases. However, the pathways of differentiation of Th17 and related Th cells (type 17 cells) and the structure of the type 17 memory population in humans are not well understood; such understanding is critical for manipulating these cells in vivo. By exploiting differences in levels of surface CCR6, we found that human type 17 memory cells, including individual T cell clonotypes, form an elongated continuum of type 17 character along which cells can be driven by increasing RORγt. This continuum includes cells preserved within the memory pool with potentials that reflect the early preferential activation of multiple over single lineages. The phenotypes and epigenomes of CCR6+ cells are stable across cell divisions under noninflammatory conditions. Nonetheless, activation in polarizing and nonpolarizing conditions can yield additional functionalities, revealing, respectively, both environmentally induced and imprinted mechanisms that contribute differentially across the type 17 continuum to yield the unusual plasticity ascribed to type 17 cells.
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Doenças Autoimunes , Células Th17 , Humanos , Diferenciação Celular , Fenótipo , Receptores CCR6/genética , Células Th1/metabolismoRESUMO
Cuprotosis, an emerging mode of cell death, has recently caught the attention of researchers worldwide. However, its impact on low-grade glioma (LGG) patients has not been fully explored. To gain a deeper insight into the relationship between cuprotosis and LGG patients' prognosis, we conducted this study in which LGG patients were divided into two clusters based on the expression of 18 cuprotosis-related genes. We found that LGG patients in cluster A had better prognosis than those in cluster B. The two clusters also differed in terms of immune cell infiltration and biological functions. Moreover, we identified differentially expressed genes (DEGs) between the two clusters and developed a cuprotosis-related prognostic signature through the least absolute shrinkage and selection operator (LASSO) analysis in the TCGA training cohort. This signature divided LGG patients into high- and low-risk groups, with the high-risk group having significantly shorter overall survival (OS) time than the low-risk group. Its predictive reliability for prognosis in LGG patients was confirmed by the TCGA internal validation cohort, CGGA325 cohort and CGGA693 cohort. Additionally, a nomogram was used to predict the 1-, 3-, and 5-year OS rates of each patient. The analysis of immune checkpoints and tumor mutation burden (TMB) has revealed that individuals belonging to high-risk groups have a greater chance of benefiting from immunotherapy. Functional experiments confirmed that interfering with the signature gene TNFRSF11B inhibited LGG cell proliferation and migration. Overall, this study shed light on the importance of cuprotosis in LGG patient prognosis. The cuprotosis-related prognostic signature is a reliable predictor for patient outcomes and immunotherapeutic response and can help to develop new therapies for LGG.
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Apoptose , Glioma , Humanos , Reprodutibilidade dos Testes , Morte Celular , Glioma/genética , Glioma/terapia , ImunoterapiaRESUMO
Banana (Musa spp.) fruits, as typical tropical fruits, are cold sensitive, and lower temperatures can disrupt cellular compartmentalization and lead to severe browning. How tropical fruits respond to low temperature compared to the cold response mechanisms of model plants remains unknown. Here, we systematically characterized the changes in chromatin accessibility, histone modifications, distal cis-regulatory elements, transcription factor binding, and gene expression levels in banana peels in response to low temperature. Dynamic patterns of cold-induced transcripts were generally accompanied by concordant chromatin accessibility and histone modification changes. These upregulated genes were enriched for WRKY binding sites in their promoters and/or active enhancers. Compared to banana peel at room temperature, large amounts of banana WRKYs were specifically induced by cold and mediated enhancer-promoter interactions regulating critical browning pathways, including phospholipid degradation, oxidation, and cold tolerance. This hypothesis was supported by DNA affinity purification sequencing, luciferase reporter assays, and transient expression assay. Together, our findings highlight widespread transcriptional reprogramming via WRKYs during banana peel browning at low temperature and provide an extensive resource for studying gene regulation in tropical plants in response to cold stress, as well as potential targets for improving cold tolerance and shelf life of tropical fruits.
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Conservação de Alimentos , Frutas , Musa , Musa/genética , Musa/fisiologia , Frutas/fisiologia , Temperatura Baixa , Histonas/metabolismo , Cromatina , Proteínas de Plantas/metabolismo , Elementos Facilitadores Genéticos , Código das Histonas , Fatores de Transcrição/metabolismo , Lipídeos de Membrana/metabolismoRESUMO
BACKGROUND: Several in silico studies have determined that quercetin, a plant flavonol, could bind with strong affinity and low free energy to SARS-CoV-2 proteins involved in viral entry and replication, suggesting it could block infection of human cells by the virus. In the present study, we examined the ex vivo ability of quercetin to inhibit of SARS-CoV-2 replication and explored the mechanisms of this inhibition. METHODS: Green monkey kidney Vero E6 cells and in human colon carcinoma Caco-2 cells were infected with SARS-CoV-2 and incubated in presence of quercetin; the amount of replicated viral RNA was measured in spent media by RT-qPCR. Since the formation of syncytia is a mechanism of SARS-CoV-2 propagation, a syncytialization model was set up using human embryonic kidney HEK293 co-expressing SARS-CoV-2 Spike (S) protein and human angiotensin converting enzyme 2 (ACE2), [HEK293(S + ACE2) cells], to assess the effect of quercetin on this cytopathic event by microscopic imaging and protein immunoblotting. RESULTS: Quercetin inhibited SARS-CoV-2 replication in Vero E6 cells and Caco-2 cells in a concentration-dependent manner with a half inhibitory concentration (IC50) of 166.6 and 145.2 µM, respectively. It also inhibited syncytialization of HEK293(S + ACE2) cells with an IC50 of 156.7 µM. Spike and ACE2 co-expression was associated with decreased expression, increased proteolytic processing of the S protein, and diminished production of the fusogenic S2' fragment of S. Furin, a proposed protease for this processing, was inhibited by quercetin in vitro with an IC50 of 116 µM. CONCLUSION: These findings suggest that at low 3-digit micromolar concentrations of quercetin could impair SARS-CoV-2 infection of human cells partly by blocking the fusion process that promotes its propagation.
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COVID-19 , Humanos , Chlorocebus aethiops , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/genética , Quercetina/farmacologia , Proteínas Virais/metabolismo , Células CACO-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Células HEK293 , Células Gigantes/patologia , Ligação ProteicaRESUMO
Based on the heterogeneous composite design of C3N4 and TiO2, composite photocatalysts of C3N4@TiO2 (with varied molar ratios of C3N4 to TiO2) were synthesized by a water bath method to degrade RhB in wastewater. The composition, morphology, structure, and photocatalytic properties of the materials were assessed through a variety of characterization techniques. The results show that TiO2 nanoparticles are uniformly coated on two-dimensional g-C3N4 nanosheets, forming relatively dense heterostructures within the C3N4@TiO2 composite. Due to the synergistic effect derived from the heterogeneous component and appropriate proportion of C3N4 and TiO2, the light absorption range is extended, and the separation/transport performance of photon-generated carrier is improved. As a result, TCNT-3 (where the molar ratio of C3N4 to TiO2 is 1:1) presents remarkable photocatalytic performance, the degradation rate of which for 60 min is 99.8%, and the reaction rate constant is calculated to be 0.0872 min-1. Moreover, the degradation efficiency remains 94.4% after 5 cycles, indicating the superior cycle stability.
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Nucleic acids, including DNA and RNA, have been considered as powerful and functional biomaterials owing to their programmable structure, good biocompatibility, and ease of synthesis. However, traditional nucleic acid-based probes have always suffered from inherent limitations, including restricted cell internalization efficiency and structural instability. In recent years, DNA nanotechnology has shown great promise for the applications of bioimaging and drug delivery. The attractive superiorities of DNA nanostructures, such as precise geometries, spatial addressability, and improved biostability, have enabled them to be a novel category of nucleic acid delivery systems for biomedical applications. In this review, we introduce the development of DNA nanotechnology, and highlight recent advances of DNA nanostructure-based delivery systems for cellular imaging and therapeutic applications. Finally, we propose the challenges as well as opportunities for the future development of DNA nanotechnology in biomedical research.
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Nanoestruturas , Ácidos Nucleicos , Nanotecnologia/métodos , DNA/genética , DNA/química , Nanoestruturas/química , Sistemas de Liberação de MedicamentosRESUMO
The global coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome (SARS)-like coronavirus (SARS-CoV-2), presents an urgent health crisis. More recently, an increasing number of mutated strains of SARS-CoV-2 have been identified globally. Such mutations, especially those on the spike glycoprotein to render its higher binding affinity to human angiotensin-converting enzyme II (hACE2) receptors, not only resulted in higher transmission of SARS-CoV-2 but also raised serious concerns regarding the efficacies of vaccines against mutated viruses. Since ACE2 is the virus-binding protein on human cells regardless of viral mutations, we design hACE2-containing nanocatchers (NCs) as the competitor with host cells for virus binding to protect cells from SARS-CoV-2 infection. The hACE2-containing NCs, derived from the cellular membrane of genetically engineered cells stably expressing hACE2, exhibited excellent neutralization ability against pseudoviruses of both wild-type SARS-CoV-2 and the D614G variant. To prevent SARS-CoV-2 infections in the lung, the most vulnerable organ for COVID-19, we develop an inhalable formulation by mixing hACE2-containing NCs with mucoadhesive excipient hyaluronic acid, the latter of which could significantly prolong the retention of NCs in the lung after inhalation. Excitingly, inhalation of our formulation could lead to potent pseudovirus inhibition ability in hACE2-expressing mouse model, without imposing any appreciable side effects. Importantly, our inhalable hACE2-containing NCs in the lyophilized formulation would allow long-term storage, facilitating their future clinical use. Thus, this work may provide an alternative tactic to inhibit SARS-CoV-2 infections even with different mutations, exhibiting great potential for treatment of the ongoing COVID-19 epidemic.
Assuntos
COVID-19/prevenção & controle , Nanoestruturas/administração & dosagem , SARS-CoV-2/efeitos dos fármacos , Adesivos/administração & dosagem , Adesivos/química , Adesivos/farmacocinética , Administração por Inalação , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Crioprotetores/química , Armazenamento de Medicamentos , Células Epiteliais/metabolismo , Excipientes/administração & dosagem , Excipientes/química , Excipientes/farmacocinética , Células HEK293 , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/química , Ácido Hialurônico/farmacocinética , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/virologia , Camundongos , Camundongos Transgênicos , Nanoestruturas/química , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Ligação Viral/efeitos dos fármacosRESUMO
OBJECTIVE: This study aimed to assess the clinical efficacy of Daiwenjiu ointment in the treatment of cervical spondylosis with cold dampness obstruction nerve root type. METHODS: A retrospective analysis was conducted on a cohort of 110 patients diagnosed with cervical spondylotic radiculopathy. Based on the treatment method, the patients were divided into two groups. The control group received electroacupuncture treatment, while the observation group received a combination of Daiwenjiu ointment and electroacupuncture treatment. The outcome measures included Japanese Orthopedic Association (JOA) scores for cervical spine function, Simplified McGill Pain Questionnaire (SF-MPQ) scores, and changes in serum inflammatory factors TNF-α and IL-1ß. RESULTS: Following treatment, the JOA score in the observation group increased from 9.45 ± 1.35 to 14.82 ± 1.29 after treatment, indicating better recovery of cervical spine function compared to the control group (p < 0.001). The SF-MPQ score in the observation group decreased to 18.25 ± 3.80 after treatment, while it remained at 30.20 ± 4.30 in the control group. This difference between the groups was statistically significant (p < 0.001). Furthermore, the observation group demonstrated a significant decrease in serum levels of TNF-α and IL-1ß after treatment compared to the control group (p < 0.001). CONCLUSION: Daiwenjiu ointment exhibits significant therapeutic effects in patients with cold dampness obstruction nerve root type cervical spondylosis. It effectively improves cervical function, reduces pain, and downregulates inflammatory cytokine levels.
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Intranasal vaccines can induce protective immune responses at the mucosa surface entrance, preventing the invasion of respiratory pathogens. However, the nasal barrier remains a major challenge in the development of intranasal vaccines. Herein, a transmucosal nanovaccine based on cationic fluorocarbon modified chitosan (FCS) is developed to induce mucosal immunity. In our system, FCS can self-assemble with the model antigen ovalbumin and TLR9 agonist CpG, effectively promoting the maturation and cross-presentation of dendritic cells. More importantly, it can enhance the production of secretory immunoglobin A (sIgA) at mucosal surfaces for those intranasally vaccinated mice, which in the meantime showed effective production of immunoglobulin G (IgG) systemically. As a proof-of-concept study, such a mucosal vaccine inhibits ovalbumin-expressing B16-OVA melanoma, especially its lung metastases. Our work presents a unique intranasal delivery system to deliver antigen across mucosal epithelia and promote mucosal and systemic immunity.
Assuntos
Imunidade nas Mucosas , Vacinas , Camundongos , Animais , Ovalbumina , Adjuvantes Imunológicos , Antígenos , Mucosa , Camundongos Endogâmicos BALB CRESUMO
Signal peptide peptidase (SPP) and its homologs, signal peptide peptidase-like (SPPL) proteases, are members of the GxGD-type aspartyl protease family, which is widespread in plants and animals and is a class of transmembrane proteins with significant biological functions. SPP/SPPLs have been identified; however, the functions of SPP/SPPL in rapeseed (Brassica napus L.) have not been reported. In this study, 26 SPP/SPPLs were identified in rapeseed and categorized into three groups: SPP, SPPL2, and SPPL3. These members mainly contained the Peptidase_A22 and PA domains, which were distributed on 17 out of 19 chromosomes. Evolutionary analyses indicated that BnaSPP/SPPLs evolved with a large number of whole-genome duplication (WGD) events and strong purifying selection. Members are widely expressed and play a key role in the growth and development of rapeseed. The regulation of rapeseed pollen fertility by the BnaSPPL4 gene was further validated through experiments based on bioinformatics analysis, concluding that BnaSPPL4 silencing causes male sterility. Cytological observation showed that male infertility caused by loss of BnaSPPL4 gene function occurs late in the mononucleate stage due to microspore dysplasia.
Assuntos
Brassica napus , Brassica rapa , Infertilidade Masculina , Animais , Humanos , Masculino , Brassica napus/genética , Ácido Aspártico Endopeptidases , Fertilidade/genética , Peptídeo HidrolasesRESUMO
BACKGROUND: The Begonia species are common shade plants that are mostly found in southwest China. They have not been well studied despite their medicinal and decorative uses because gene penetration, decreased adaptability, and restricted availability are all caused by frequent interspecific hybridization. RESULT: To understand the patterns of mutation in the chloroplast genomes of different species of Begonia, as well as their evolutionary relationships, we collected seven Begonia species in China and sequenced their chloroplast genomes. Begonia species exhibit a quadripartite structure of chloroplast genomes (157,634 - 169,694 bp), consisting of two pairs of inverted repeats (IR: 26,529 - 37,674 bp), a large single copy (LSC: 75,477 - 86,500 bp), and a small single copy (SSC: 17,861 - 18,367 bp). 128-143 genes (comprising 82-93 protein-coding genes, 8 ribosomal RNAs, and 36-43 transfer RNAs) are found in the chloroplast genomes. Based on comparative analyses, this taxon has a relatively similar genome structure. A total of six substantially divergent DNA regions (trnT-UGU-trnL-UAA, atpF-atpH, ycf4-cemA, psbC-trnS-UGA, rpl32-trnL-UAG, and ccsA-ndhD) are found in the seventeen chloroplast genomes. These regions are suitable for species identification and phylogeographic analysis. Phylogenetic analysis shows that Begonia species that were suited to comparable environments grouped in a small clade and that all Begonia species formed one big clade in the phylogenetic tree, supporting the genus' monophyly. In addition, positive selection sites were discovered in eight genes (rpoC1, rpoB, psbE, psbK, petA, rps12, rpl2, and rpl22), the majority of which are involved in protein production and photosynthesis. CONCLUSION: Using these genome resources, we can resolve deep-level phylogenetic relationships between Begonia species and their families, leading to a better understanding of evolutionary processes. In addition to enhancing species identification and phylogenetic resolution, these results demonstrate the utility of complete chloroplast genomes in phylogenetically and taxonomically challenging plant groupings.
Assuntos
Begoniaceae , Genoma de Cloroplastos , Humanos , Filogenia , Begoniaceae/genética , Genômica/métodos , Cloroplastos/genética , Sequência de BasesRESUMO
BACKGROUND: Circulating tumor DNA (ctDNA) has been becoming a novel convenient and noninvasive method for dynamically monitoring landscape of genomic information to guild personalized cancer treatment. In this study we comprehensively evaluated the additional value of plasma ctDNA to routine tissue next generation sequencing (NGS) of therapeutically targetable mutations in lung cancers. METHODS: The tumor tissues and peripheral blood samples from 423 cases of patients with lung cancer were subjected to NGS of mutations in oncodrivers (EGFR, ERBB2, ALK, ROS1, C-MET, KRAS, BRAF, RET, BRCA1 and BRCA2). RESULTS: One hundred and ninety-seven cases showed both plasma and tissue positive and 96 showed both negative. The concordance for tissue and blood detection was 69.27% (293/423). 83 (19.62%) cases showed positive by tissue NGS alone and 47 (11.11%) positive by plasma ctDNA alone. The sensitivity of tissue and plasma detection was 85.63%, and 74.62%, respectively. Plasma had lower detection and sensitivity than tissue, but plasma additionally detected some important mutations which were omitted by tissue NGS. Plasma plus tissue increased the detection rate of 66.19% by tissue alone to 77.30% as well as the sensitivity of 85.63-100%. Similar results were also observed when the cases were classified into subpopulations according to different stages (IV vs. III vs. I-II), grades (low vs. middle grade) and metastatic status (metastasis vs. no metastasis). CONCLUSION: Plasma ctDNA shares a high concordance with tissue NGS, and plasma plus tissue enhances the detection rate and sensitivity by tissue alone, implying that the tissue and plasma detection should be mutually complementary in the clinical application.
Assuntos
DNA Tumoral Circulante , Neoplasias Pulmonares , Humanos , DNA Tumoral Circulante/genética , Biomarcadores Tumorais/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Pulmonares/patologia , Mutação , Sequenciamento de Nucleotídeos em Larga Escala/métodosRESUMO
Schizophrenia (SCZ) is a severe psychiatric disorder characterized by positive symptoms, negative symptoms, and cognitive deficits. Current antipsychotic treatment in SCZ improves positive symptoms but has major side effects and little impact on negative symptoms and cognitive impairment. The pathoetiology of SCZ remains unclear, but is known to involve small GTPase signaling. Rho kinase, an effector of small GTPase Rho, is highly expressed in the brain and plays a major role in neurite elongation and neuronal architecture. This study used a touchscreen-based visual discrimination (VD) task to investigate the effects of Rho kinase inhibitors on cognitive impairment in a methamphetamine (METH)-treated male mouse model of SCZ. Systemic injection of the Rho kinase inhibitor fasudil dose-dependently ameliorated METH-induced VD impairment. Fasudil also significantly suppressed the increase in the number of c-Fos-positive cells in the infralimbic medial prefrontal cortex (infralimbic mPFC) and dorsomedial striatum (DMS) following METH treatment. Bilateral microinjections of Y-27632, another Rho kinase inhibitor, into the infralimbic mPFC or DMS significantly ameliorated METH-induced VD impairment. Two proteins downstream of Rho kinase, myosin phosphatase-targeting subunit 1 (MYPT1; Thr696) and myosin light chain kinase 2 (MLC2; Thr18/Ser19), exhibited increased phosphorylation in the infralimbic mPFC and DMS, respectively, after METH treatment, and fasudil inhibited these increases. Oral administration of haloperidol and fasudil ameliorated METH-induced VD impairment, while clozapine had little effect. Oral administration of haloperidol and clozapine suppressed METH-induced hyperactivity, but fasudil had no effect. These results suggest that METH activates Rho kinase in the infralimbic mPFC and DMS, which leads to cognitive impairment in male mice. Rho kinase inhibitors ameliorate METH-induced cognitive impairment, perhaps via the cortico-striatal circuit.
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Disfunção Cognitiva , Metanfetamina , Proteínas Monoméricas de Ligação ao GTP , Inibidores de Proteínas Quinases , Esquizofrenia , Animais , Masculino , Camundongos , Clozapina , Disfunção Cognitiva/tratamento farmacológico , Haloperidol/farmacologia , Haloperidol/uso terapêutico , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , Esquizofrenia/induzido quimicamente , Esquizofrenia/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
The rational design of photocatalysts with efficiency and stability is highly desirable but remains challenging. Here, we report a supramolecular self-assembly strategy to construct hollow phosphorus-doped g-C3N4 microboxes (PCNMs). Considering the effects of multiple parameters on the structure and activity of samples, the orthogonal design is innovatively introduced to optimize technology parameters for screening high-performance g-C3N4. Under visible light irradiation (λ ≥ 420 nm), rhodamine B (RhB, 4 mg L-1) is completely degraded in just 80 seconds in the presence of the optimal PCNM. The kinetic rate constant of RhB degradation with the PCNM is 3.4633 min-1, demonstrating unprecedented activity that is about 112 times higher than that of bulk g-C3N4 (0.0309 min-1) synthesized by direct polycondensation of melamine. Additionally, the optimal PCNM also shows enhanced degradation efficiency for tetracycline. The outstanding properties are primarily attributed to the hollow architecture, high specific surface area, and phosphorus doping. This work advances the design of photocatalysts correlating various factors, opening an avenue for optimizing photocatalytic synthesis and activity.
RESUMO
A novel CuO-Fe3O4 encapsulated in the carbon framework with abundant oxygen vacancies (CuO-Fe3O4@C) was successfully prepared by thermal conversion of Cu(OAc)2/Fe-metal organic framework. The as-prepared catalyst exhibited excellent peroxymonosulfate (PMS) activation performance, good recyclability and fast magnetic separation. Under optimal conditions, the added BPA (60 mg/L) could be completely removed by CuO-Fe3O4@C/PMS system within 15 min with the degradation rate constant (k) of 0.32 min-1, being 10.3 and 246.2 times that in CuO/PMS (0.031min-1) and Fe3O4/PMS (0.0013 min-1) system. A deep mineralization rate of BPA (ï¼80%) was achieved within 60 min. The results demonstrated the synergistic effect of bimetallic clusters, oxygen vacancies and carbon framework was a key benefit for the exposure of more active sites, the electron donor capacity and the mass transfer of substrates, thereby promoting the decomposition of BPA. Capture experiments and EPR indicated that 1O2 was the predominant reactive oxygen species (ROSs). The degradation routes of BPA and the activation mechanism of PMS were proposed. This study offers an opportunity to develop promising MOFs-derived hybrid catalysts with tailored structures and properties for the practical application of SR-AOPs.
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Carbono , Oxigênio , Carbono/químicaRESUMO
Rationale: Interstitial lung abnormalities (ILAs) are being increasingly identified in clinical practice. In particular, for subpleural nonfibrotic ILAs, the risk of progression over time and the risk factors for progressive behavior are still largely unknown. Objectives: To determine the age band prevalence of ILAs and the risk of radiological progression of subpleural nonfibrotic ILAs over time in a large health checkup population and to identify how reticulation contributes to the risk of radiological progression. Methods: On the basis of the ILAs definition by the Fleischner Society, low-dose chest computed tomography images from the community-dwelling population who have undergone health checkups were evaluated for ILAs. Multivariable logistic regression was used to assess the risk of radiological progression. Measurements and Main Results: Among 155,539 individuals, 3,300 (2.1%) were confirmed to have ILAs: the vast majority (81.7%) were defined as subpleural nonfibrotic ILAs. The prevalence of ILAs increased linearly with age (P for trend < 0.0001). Of 454 individuals with subpleural nonfibrotic ILAs, 198 (43.6%) had radiological progression over 4 years. The presence of reticulation on initial imaging was an independent predictor of radiological progression (odds ratio, 1.9; 95% confidence interval, 1.2-3.0; P = 0.0040). No difference in radiological progression was identified between subpleural nonfibrotic ILAs with extensive reticulation and subpleural fibrotic ILAs (73.0% vs. 68.8%; P = 0.7626). Conclusions: The prevalence of ILAs increases linearly with age. Nearly half of subpleural nonfibrotic ILAs progress radiologically over 4 years. The presence of reticulation is a risk factor for radiological progression. Subpleural nonfibrotic ILAs with extensive reticulation are likely to be a feature of subpleural fibrotic ILAs.
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Doenças Pulmonares Intersticiais , Anormalidades do Sistema Respiratório , Humanos , Pulmão/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/epidemiologia , Doenças Pulmonares Intersticiais/etiologia , Anormalidades do Sistema Respiratório/complicações , Fatores de Risco , Tomografia Computadorizada por Raios X/métodosRESUMO
Enterobacter cloacae exhibits strong adhesion and invasion properties that contribute its ability to infect the host; it is considered an important opportunistic pathogen throughout the world. To control the spread of E. cloacae, simple, rapid, and accurate detection methods are required. Current methods suffer from various shortcomings and do not meet the demand for on-site quickly detection. Using recombinase polymerase amplification combined with lateral flow strip (RPA-LFS), an isothermal detection method was developed to target the outer membrane protein X (ompX) gene of E. cloacae. This reaction can be performed in 30 min at 37 °C. Limit of detection of 10 CFU/reaction was equivalent to that of the qPCR method. The detection accuracy of clinical samples was also equal to that of the qPCR method. In this study, we developed the RPA-LFS assay, which is simple, rapid, accurate, and does not require a laboratory facility. This assay may prove useful for detecting E. cloacae on-site.
Assuntos
Técnicas de Amplificação de Ácido Nucleico , Recombinases , Recombinases/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Enterobacter cloacae/genética , Sensibilidade e EspecificidadeRESUMO
Copper is a trace element essential for the maintenance of normal physiological functions in cardiovascular system, and its transport and metabolisms are regulated by various copper proteins such as copper-based enzymes, copper chaperones and copper transporters. The disturbance of copper level or abnormal expression of copper proteins are closely associated with the development of cardiovascular diseases such as atherosclerosis, hypertension, ischemic heart disease, myocardial hypertrophy and heart failure. Thus, intervention of copper ion signaling pathways is expected to be an effective measure for treating cardiovascular diseases. Some copper complexes, such as trientine, copper-aspirinate complex and copper (II) diethyldithiocarbamate, have been found to play a role in the prevention and treatment of cardiovascular diseases and possess potential prospects. Exploring the role of copper in maintaining normal cardiovascular status and the potential application of copper complexes in the treatment of cardiovascular diseases may lay a foundation for finding new targets for prevention and treatment of various cardiovascular diseases, and provide new ideas for clinical treatment of cardiovascular diseases.