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1.
Immunity ; 53(1): 98-105.e5, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32561270

RESUMO

Antibody responses develop following SARS-CoV-2 infection, but little is known about their epitope specificities, clonality, binding affinities, epitopes, and neutralizing activity. We isolated B cells specific for the SARS-CoV-2 envelope glycoprotein spike (S) from a COVID-19-infected subject 21 days after the onset of clinical disease. 45 S-specific monoclonal antibodies were generated. They had undergone minimal somatic mutation with limited clonal expansion, and three bound the receptor-binding domain (RBD). Two antibodies neutralized SARS-CoV-2. The most potent antibody bound the RBD and prevented binding to the ACE2 receptor, while the other bound outside the RBD. Thus, most anti-S antibodies that were generated in this patient during the first weeks of COVID-19 infection were non-neutralizing and target epitopes outside the RBD. Antibodies that disrupt the SARS-CoV-2 S-ACE2 interaction can potently neutralize the virus without undergoing extensive maturation. Such antibodies have potential preventive and/or therapeutic potential and can serve as templates for vaccine design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Hipermutação Somática de Imunoglobulina/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2 , Anticorpos Monoclonais/imunologia , Linfócitos B/imunologia , Sítios de Ligação , COVID-19 , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Epitopos de Linfócito B/imunologia , Humanos , Pandemias/prevenção & controle , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Ligação Proteica , Receptores Virais/metabolismo , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/metabolismo , Vacinas Virais/imunologia
2.
Electrophoresis ; 45(3-4): 275-287, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37768831

RESUMO

Microcystin-LR (MC-LR), as a hepatotoxin, can cause liver swelling, hepatitis, and even liver cancer. In this study, MC-LR aptamer (Apt-3) modified graphene oxide (GO) was designed to enrich MC-LR in white jade snail (Achatina fulica) and pond water, followed by matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) analysis. Results indicated that the Apt-3/PEG/GO nanocomposites were highly specific to MC-LR, and the detection limit of MALDI-MS was 0.50 ng/mL. Moreover, the MC-LR can be released from nanocomposites at 75°C, thus, the reuse of Apt-3/PEG/GO is realized. Real sample analysis indicated that the Apt-3/PEG/GO nanocomposites coupled with MALDI-MS were efficient in detecting trace amounts of MC-LR in real samples. With the merits of being low cost, reusable, and easy to besynthesized, this Apt-3/PEG/GO MALDI-MS is expected to be comprehensively applied by anchoring suitable aptamers for different targets.


Assuntos
Grafite , Lasers , Toxinas Marinhas , Microcistinas , Oligonucleotídeos , Caramujos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
3.
Electrophoresis ; 42(16): 1552-1559, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34128241

RESUMO

Oyster is rich in plasmalogens that are ether phospholipids with biological functions to human body. Air-frying is a popular technique for preparing delicious oyster but makes the plasmalogens vulnerable to oxidation. In this study, the effect of air-frying processing on plasmalogens oxidation was studied by lipidomic approach. Plasmalogens were always mixed with normal phospholipids, thus the lipid extract was treated with mild acid hydrolysis to rapidly degrade plasmalogens owing to the acid lability of vinyl ether linkage at sn-1 position. After hydrophilic interaction chromatography MS/MS analysis, there were three plasmalogen classes, plasmanylcholine, plasmanylethanolamine, and plasmanylinositol, completely separated, and each plasmalogen molecular species was identified and quantified. It indicated that the content of plasmalogens underwent an obvious decrease during the air-frying process. To weaken such effect, the influence of air-frying temperature was further inspected by multivariate statistical analyses. The main variables, including the ions of m/z 756.4927, 784.5486, 828.5812, etc., were revealed by unsupervised principle component analysis, supervised orthogonal partial least-square analysis, and variable importance in projection plot. As a conclusion, air-frying has health benefits in reducing fat content but destructive to plasmalogens, thus interventions are recommended to prevent the degradation of plasmalogens.


Assuntos
Ostreidae , Animais , Hidrólise , Lipidômica , Plasmalogênios , Espectrometria de Massas em Tandem
4.
PLoS Pathog ; 14(6): e1007120, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29933399

RESUMO

Broadly neutralizing HIV-1 antibodies (bNAbs) isolated from infected subjects display protective potential in animal models. Their elicitation by immunization is thus highly desirable. The HIV-1 envelope glycoprotein (Env) is the sole viral target of bnAbs, but is also targeted by binding, non-neutralizing antibodies. Env-based immunogens tested so far in various animal species and humans have elicited binding and autologous neutralizing antibodies but not bNAbs (with a few notable exceptions). The underlying reasons for this are not well understood despite intensive efforts to characterize the binding specificities of the elicited antibodies; mostly by employing serologic methodologies and monoclonal antibody isolation and characterization. These approaches provide limited information on the ontogenies and clonal B cell lineages that expand following Env-immunization. Thus, our current understanding on how the expansion of particular B cell lineages by Env may be linked to the development of non-neutralizing antibodies is limited. Here, in addition to serological analysis, we employed high-throughput BCR sequence analysis from the periphery, lymph nodes and bone marrow, as well as B cell- and antibody-isolation and characterization methods, to compare in great detail the B cell and antibody responses elicited in non-human primates by two forms of the clade C HIV Env 426c: one representing the full length extracellular portion of Env while the other lacking the variable domains 1, 2 and 3 and three conserved N-linked glycosylation sites. The two forms were equally immunogenic, but only the latter elicited neutralizing antibodies by stimulating a more restricted expansion of B cells to a narrower set of IGH/IGK/IGL-V genes that represented a small fraction (0.003-0.02%) of total B cells. Our study provides new information on how Env antigenic differences drastically affect the expansion of particular B cell lineages and supports immunogen-design efforts aiming at stimulating the expansion of cells expressing particular B cell receptors.


Assuntos
Linfócitos B/imunologia , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Células Cultivadas , Glicosilação , Infecções por HIV/genética , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV-1/genética , Humanos , Imunização , Macaca mulatta , Receptores de Antígenos de Linfócitos B/imunologia
5.
Electrophoresis ; 41(5-6): 379-385, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32040861

RESUMO

Justicia procumbens is a food and medicine homologous variety, popularly used for making vegetable soups. In this study, a novel mesoporous silica was synthesized and used as the sorbent of SPE for the purification of lignans from J. procumbens. A laboratory-made SPE cartridge was packed with 100 mg of mesoporous silica, which was washed with 10% methanol and eluted using 0.8 mL acetonitrile after sample loading. Afterward, the extract was analyzed by ultra-performance liquid chromatography (UPLC) and MS/MS. All the lignans were efficiently separated in 6 min with the noise level in the range of 50-150 cps. 6'-Hydroxy justicidin B, 6'-hydroxy justicidin A, justicidin B, chinensinaphthol methyl ether, justicidin C, and neojusticdin A were identified to be the dominant molecular species in J. procumbens with contents of 0.065-0.37 mg/g in three tested sample batches from different geographic origins. In conclusion, the proposed mesoporous silica based SPE UPLC-MS/MS method is efficient in linearity (R2 = 0.9989-0.9996), sensitivity (LOD ≤0.13 µg/kg and LOQ ≤0.42 µg/kg), precision (RSDintra-day ≤3.12 and RSDinter-day ≤4.56), and recovery (83.42-96.11%, RSD ≤2.88%).


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Justicia/química , Lignanas/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dióxido de Silício/química
6.
Mol Cell Probes ; 52: 101569, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32268179

RESUMO

Largemouth bass ranavirus (LMBV) has been recognized as the causative pathogen responsible for infectious skin ulcerative syndrome in cultured largemouth bass in China. A fast and simple LMBV detection method is urgently needed. Here, a loop-mediated isothermal amplification (LAMP) assay was established for the detection of this virus using primers targeting the major capsid protein gene of LMBV. The amplification conditions were optimized; the assay was specific for the diagnosis of LMBV, as there was no cross-reactivity with other four Iridoviridae viruses (large yellow croaker iridovirus, Singapore grouper iridovirus, tiger frog virus, and soft-shelled turtle iridovirus), grass carp reovirus, white spot syndrome virus, or healthy largemouth bass. The sensitivity of the LAMP assay was found to be 8.55 × 101 copies/µL of LMBV DNA, which was 10-fold higher than that of the conventional PCR. Application of the LAMP assay was evaluated using 10 clinical samples, and the results indicated the reliability of the test as a rapid, field diagnostic tool for LMBV detection. Thus, the simplicity and nearly instrument-free LAMP method provides an alternative for rapid and sensitive detection of LMBV and has great potential for early diagnosis of LMBV infection in the farm.


Assuntos
Bass/virologia , Infecções por Vírus de DNA/diagnóstico , Infecções por Vírus de DNA/veterinária , Doenças dos Peixes/diagnóstico , Reação em Cadeia da Polimerase/métodos , Ranavirus/fisiologia , Animais , Sequência de Bases , Doenças dos Peixes/virologia , Sensibilidade e Especificidade
7.
Electrophoresis ; 40(14): 1805-1811, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31106441

RESUMO

Microcystins are a group of cyanotoxins which interact with the C-terminal region of PP1 and PP2A proteins, so denaturation and inactivation are necessary for breaking covalent binding to release microcystins. In this study, a novel extraction method was developed by laser irradiation desorption of microcystins from fish protein. The sample was mixed with aqueous methanol and irradiated by a 450 nm laser, with an optimized value of laser power density at 8 W and exposure time at 5 min. ThenLC-MS/MS was applied for the determination of microcystins in fish extracts. The ionization behaviors of microcystins were investigated firstly, and doubly charged microcystins were selected as precursor ions in multiple reaction monitoring scan for quantification. This proposed quantitative method was well validated in terms of selectivity, linearity, sensitivity, accuracy, recovery, and stability. The successful application of this LC-MS/MS method showed its ability for the analysis of microcystins in low concentration, and it would be of significant interest for environmental and food safety applications to ensure the safety of fish and related products.


Assuntos
Proteínas de Peixes/química , Peixes , Microcistinas/análise , Animais , Técnicas Biossensoriais/métodos , Cromatografia Líquida de Alta Pressão/métodos , Inocuidade dos Alimentos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem
8.
Mol Cell Probes ; 47: 101420, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295518

RESUMO

Codfish is a commercially important species of sea fish and plays an important role in the world fishery. In our study, two loop-mediated isothermal amplification (LAMP) assays (real-time fluorescence LAMP and visual LAMP) were established for the identification of three cod species in Gadidae (Gadus morhua, Gadus macrocephalus and Melanogrammus aeglefinus). 12S rDNA gene was used to design primers to distinguish the Gadidae and non-Gadidae species, and the mitochondrial Cytb gene was selected for discrimination of three cod species. After optimization, the 12S rDNA system and species-specific systems performed well, and target cod DNA could be detected in single or mixed samples. In the species-specific systems, the absolute limit of detection (LODa) of three cod species were 285, 37 and 197 pg/µL, and the relative limit of detection (LODr) reached to 1%, 0.1% and 1%, respectively. In the 12S rDNA system, the LODa of three cod species were 28.5, 37 and 19.7 pg/µL, respectively, and the LODr reached to 0.1%. Through the detection of 13 commercial cod products, the LAMP systems can detect cod contents in raw materials and deep-processed products as well. It indicated that the methods developed in this study have strong practicability and can meet the needs of routine testing.


Assuntos
Citocromos b/genética , Gadus morhua/classificação , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Animais , Primers do DNA/genética , DNA Ribossômico/genética , Gadus morhua/genética , Limite de Detecção , RNA Ribossômico/genética , Especificidade da Espécie
9.
J Biol Chem ; 292(38): 15705-15716, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28724631

RESUMO

The receptor tyrosine kinase family consisting of Tyro3, Axl, and Mer (TAM) is one of the most recently identified receptor tyrosine kinase families. TAM receptors are up-regulated postnatally and maintained at high levels in adults. They all play an important role in immunity, but Axl has also been implicated in cancer and therefore is a target in the discovery and development of novel therapeutics. However, of the three members of the TAM family, the Axl kinase domain is the only one that has so far eluded structure determination. To this end, using differential scanning fluorimetry and hydrogen-deuterium exchange mass spectrometry, we show here that a lower stability and greater dynamic nature of the Axl kinase domain may account for its poor crystallizability. We present the first structural characterization of the Axl kinase domain in complex with a small-molecule macrocyclic inhibitor. The Axl crystal structure revealed two distinct conformational states of the enzyme, providing a first glimpse of what an active TAM receptor kinase may look like and suggesting a potential role for the juxtamembrane region in enzyme activity. We noted that the ATP/inhibitor-binding sites of the TAM members closely resemble each other, posing a challenge for the design of a selective inhibitor. We propose that the differences in the conformational dynamics among the TAM family members could potentially be exploited to achieve inhibitor selectivity for targeted receptors.


Assuntos
Compostos Macrocíclicos/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/química , Receptores Proteína Tirosina Quinases/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Membrana Celular/enzimologia , Desenho de Fármacos , Estabilidade Enzimática , Humanos , Ligantes , Compostos Macrocíclicos/farmacologia , Modelos Moleculares , Fosforilação , Ligação Proteica , Domínios Proteicos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptor Tirosina Quinase Axl
10.
Environ Microbiol ; 20(1): 200-213, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29076601

RESUMO

The small-molecule sunscreen compounds, mycosporine-like amino acids (MAAs), have strong ultraviolet (UV) absorption and can protect cyanobacteria against UV-B damage. However, the molecular mechanism underlying UV-B signaling and MAA chemical diversity remain largely unclear. Here, we identified a five-gene cluster for MAA biosynthesis in the solar radiation and desiccation tolerant cyanobacterium Nostoc flagelliforme. A LuxR family protein OrrA was identified as a positive UV-B responsive regulator binding to the promoter region of this gene cluster. OrrA functions as an activator mediating the UV-B induced MAA biosynthesis. Overexpression of orrA strengthened its UV-B tolerance during desiccation, and enhanced the photosynthetic recovery upon rehydration. Heterologous expression of this gene cluster in Anabaena PCC 7120 produces the same MAA as that in field samples of N. flagelliforme. The MAA structure is assigned as mycosporine-2-(4-deoxygadusolyl-ornithine) with a molecular weight of 756 Da, the structurally unique MAA compound reported to date. This MAA was catalyzed by mysD-mysC2-mysC1 encoding proteins from 4-deoxygadusol, which was synthesized through the catalysis of mysA-mysB products. Thus, we elucidated the transcriptional mechanism for a novel type MAA biosynthesis in solar radiation and desiccation tolerant cyanobacteria, which shed light on the identification of other components for UV-B signaling in cyanobacteria.


Assuntos
Aminoácidos/biossíntese , Nostoc/genética , Nostoc/metabolismo , Proteínas Repressoras/metabolismo , Protetores Solares/análise , Transativadores/metabolismo , Raios Ultravioleta , Dessecação , Lisina/análise , Família Multigênica/genética , Ornitina/análise , Fotossíntese , Protetores Solares/química , Transcrição Gênica/genética
11.
Proc Natl Acad Sci U S A ; 111(1): 173-8, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24347635

RESUMO

Covalent inhibition is a reemerging paradigm in kinase drug design, but the roles of inhibitor binding affinity and chemical reactivity in overall potency are not well-understood. To characterize the underlying molecular processes at a microscopic level and determine the appropriate kinetic constants, specialized experimental design and advanced numerical integration of differential equations are developed. Previously uncharacterized investigational covalent drugs reported here are shown to be extremely effective epidermal growth factor receptor (EGFR) inhibitors (kinact/Ki in the range 10(5)-10(7) M(-1)s(-1)), despite their low specific reactivity (kinact ≤ 2.1 × 10(-3) s(-1)), which is compensated for by high binding affinities (Ki < 1 nM). For inhibitors relying on reactivity to achieve potency, noncovalent enzyme-inhibitor complex partitioning between inhibitor dissociation and bond formation is central. Interestingly, reversible binding affinity of EGFR covalent inhibitors is highly correlated with antitumor cell potency. Furthermore, cellular potency for a subset of covalent inhibitors can be accounted for solely through reversible interactions. One reversible interaction is between EGFR-Cys797 nucleophile and the inhibitor's reactive group, which may also contribute to drug resistance. Because covalent inhibitors target a cysteine residue, the effects of its oxidation on enzyme catalysis and inhibitor pharmacology are characterized. Oxidation of the EGFR cysteine nucleophile does not alter catalysis but has widely varied effects on inhibitor potency depending on the EGFR context (e.g., oncogenic mutations), type of oxidation (sulfinylation or glutathiolation), and inhibitor architecture. These methods, parameters, and insights provide a rational framework for assessing and designing effective covalent inhibitors.


Assuntos
Resistência a Medicamentos , Inibidores Enzimáticos/síntese química , Receptores ErbB/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Catálise , Linhagem Celular Tumoral , Química Farmacêutica , Cisteína/química , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática , Receptores ErbB/química , Humanos , Concentração Inibidora 50 , Espectrometria de Massas , Oxigênio/química , Fosforilação , Ligação Proteica , Conformação Proteica , Quinazolinas/química , Transdução de Sinais
12.
Mol Cell Probes ; 30(1): 22-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26772407

RESUMO

Squids are distributed worldwide, including many species of commercial importance, and they are often made into varieties of flavor foods. The rapid identification methods for squid species especially their processed products, however, have not been well developed. In this study, quantitative real-time PCR (qPCR) systems based on specific primers and TaqMan probes have been established for rapid and accurate identification of four common squid species (Ommastrephes bartramii, Dosidicus gigas, Illex argentinus, Todarodes pacificus) in Chinese domestic market. After analyzing mitochondrial genes reported in GenBank, the mitochondrial cytochrome b (Cytb) gene was selected for O. bartramii detection, cytochrome c oxidase subunit I (COI) gene for D. gigas and T. Pacificus detection, ATPase subunit 6 (ATPase 6) gene for I. Argentinus detection, and 12S ribosomal RNA (12S rDNA) gene for designing Ommastrephidae-specific primers and probe. As a result, all the TaqMan systems are of good performance, and efficiency of each reaction was calculated by making standard curves. This method could detect target species either in single or mixed squid specimen, and it was applied to identify 12 squid processed products successfully. Thus, it would play an important role in fulfilling labeling regulations and squid fishery control.


Assuntos
DNA Mitocondrial/genética , Decapodiformes/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Análise de Sequência de DNA/métodos , Animais , Citocromos b/genética , Primers do DNA , DNA Mitocondrial/química , Decapodiformes/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , ATPases Mitocondriais Próton-Translocadoras/genética , RNA Ribossômico/genética , Reprodutibilidade dos Testes , Especificidade da Espécie
13.
Planta ; 240(6): 1335-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25204630

RESUMO

MicroRNAs (miRNAs) play important regulatory roles in plant development and stress responses. Tomato is an economically important vegetable crop in the world with publicly available genomic information database, but only a limited number of tomato miRNAs have been identified. In this study, two independent small RNA libraries from mock and Cucumber mosaic virus (CMV)-infected tomatoes were constructed, respectively, and sequenced with a high-throughput Illumina Solexa system. Based on sequence analysis and hairpin structure prediction, a total of 50 plant miRNAs and 273 potentially candidate miRNAs (PC-miRNAs) were firstly identified in tomato, with 12 plant miRNAs and 82 PC-miRNAs supported by both the 3p and 5p strands. Comparative analysis revealed that 79 miRNAs (including 15 new tomato miRNAs) and 40 PC-miRNAs were differentially expressed between the two libraries, and the expression patterns of some new tomato miRNAs and PC-miRNAs were further validated by qRT-PCR. Moreover, potential targets for some of the known and new tomato miRNAs were identified by the recently developed degradome sequencing approach, and target annotation indicated that they were involved in multiple biological processes, including transcriptional regulation and virus resistance. Gene ontology analysis of these target transcripts demonstrated that defense response- and photosynthesis-related genes were most affected in CMV-Fny-infected tomatoes. Because tomato is not only an important crop but also is a genetic model for basic biology research, our study contributes to the understanding of miRNAs in response to virus infection.


Assuntos
Cucumovirus/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , MicroRNAs/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/virologia , Solanum lycopersicum/genética , Solanum lycopersicum/virologia , Sequência de Bases , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Genes de Plantas , MicroRNAs/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de RNA
14.
Neurosci Lett ; 818: 137560, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979715

RESUMO

Plasmalogens (Pls) are considered to play a potential role in the treatment of neurodegenerative diseases. In the present study, an Alzheimer's disease (AD) model of zebrafish induced by AlCl3 was established to investigate whether the marine-derived Pls could alleviate cognitive impairments of AD zebrafish. Behavioral tests were carried out to assess the athletic ability. The transcriptional profiles of zebrafish in the control, AD model and AD_PLS group were compared and analyzed to determine the potential mechanisms of dietary Pls on AD. The study found that Pls could reverse athletic impairment in the AD zebrafish model, and the expression levels of genes related to ferroptosis, synaptic dysfunction and apoptosis were significantly altered between experimental groups. Further analysis showed that all of these genes were associated with oxidative stress (OS). These data suggest that healthy protective role of marine-derived Pls on AD zebrafish may result from inhibition of ferroptosis and neuronal apoptosis, restoring synaptic neurotransmission release, and reducing neuroinflammation. Among them, Oxidative stress is acted as the center to connect different regulation pathways. This study provides evidence to support the essential roles of OS in pathogenesis of AD, and the application of Pls in relieving AD.


Assuntos
Doença de Alzheimer , Ferroptose , Fármacos Neuroprotetores , Animais , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peixe-Zebra/metabolismo , Plasmalogênios/metabolismo , Plasmalogênios/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Apoptose , Transmissão Sináptica
15.
Mol Biol Rep ; 40(5): 3713-22, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23277401

RESUMO

The economic importance of Solanaceae plant species is well documented, and tomato has become a model for fleshy fruit development and ripening studies. Plant microRNAs (miRNAs) are small endogenous RNAs that are involved in a variety of activities including plant development, signal transduction and protein degradation, as well as response to environment stress and pathogen invasion. Here in this study, we aimed at quantifying the expression alterations of nine miRNAs and target mRNAs in tomato flower and fruit development upon Cucumber mosaic virus (CMV) and Tomato aspermy virus infections. Three different CMV strains CMV-Fny, CMV-FnyΔ2b and CMV-Fny-satT1 were used in our investigation, and the miRNA/mRNA expression alterations were analyzed by real-time quantitative RT-PCR. The results shown the levels of several miRNA/mRNA pairs were increased upon virus infections. However, the increased level of individual miRNA differed for different virus strains, reflecting differences in severity of symptom phenotypes. The altered expression patterns of these miRNA/mRNA pairs and their predicted functions indicate the possible roles in flower and fruit development, and provide experimental data for understanding the miRNA-mediated phenotype alterations in tomato fruit.


Assuntos
Cucumovirus/fisiologia , Frutas/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Doenças das Plantas/genética , Vírus de Plantas/fisiologia , Solanum lycopersicum/genética , Flores/genética , Flores/virologia , Expressão Gênica , Solanum lycopersicum/virologia , Fenótipo , Doenças das Plantas/virologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
J Nanosci Nanotechnol ; 13(6): 4421-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23862515

RESUMO

Usually, modifications in normal microRNAs (miRs)-dependent gene expression are induced in transgenic plants expressing viral silencing suppressors or in viruses-inoculated plants. These phenomena are generally interpreted as a side effect of the antiviral silencing suppression. However, it has been recently reported that certain animal miRs prevent viral infection by directly interfering with pathogen replication or by binding to viral transcripts. To investigate whether such mechanisms operate in plants, we performed in silico analysis using tomato miR/miR* sequences and genomes of Cucumber mosaic virus (CMV)-Fny (the severe strain), CMV-Q (the mild strain), the aggravated satellite RNA (satRNA) variant satT1 and the attenuated variant satYn12. Results showed that a total of 38 and 37 miR/miR* sequences could bind to genomic RNAs of CMV-Fny and CMV-Q, respectively. But only one sequence could bind to safT1 and three to satYn12. Interestingly, we found that these miRs/miR*s exhibited significant complementarity within 2a and 3a Open Reading Frames (ORFs) of CMV. And most of the sequences with potential to bind viral genomes were of miR*s, suggesting novel role of miR*s in host defense response. This finding is noteworthy as plant miR* sequences are presently thought very unstable and are not assigned with any function. Finally, we could predict targets in tomato database for the miR/miR* sequences that are highlighted in our study, most of them are involved in plant metabolism. Overall, these results shed light on the possible novel role of plant miR/miR* in antiviral defense mechanisms.


Assuntos
Cucumovirus/genética , Genoma Viral , MicroRNAs/genética , Solanum lycopersicum/virologia
17.
J Nanosci Nanotechnol ; 13(12): 8266-74, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24266223

RESUMO

Genetically modified (GM) tomatoes have been approved for commercialization in many countries since the first GM tomato FLAVR SAVR was permitted for planting in 1994. To meet the requirement of the GM tomatoes labeling policy, in this study we firstly set up the conventional PCR and multiplex PCR detection system for screening the universal elements transformed into tomato, such as cauliflower mosaic virus 35s (CaMV 35s) promoter, nopaline synthase (nos) terminator of Agrobacterium tumefaciens, neomycinphosphotransferase (nptII) gene, and the specifically inserted heterologous DNA sequence between CaMV 35s promoter and anti-sense ethylene-forming enzyme (anti-EFE) gene in GM tomato "Huafan No. 1." Tomato lat52, mcpi, fru and apx genes were used as endogenous reference genes. Besides these, a muParaflo microfluidic microarray was also developed to screen the exogenous or endogenous genes of GM tomatoes. A total of 957 probes were designed, which can be classified into two categories according to their purpose: the first for screening GM plants from un-transgenic plants based on the common elements such as promoter, reporter and terminator genes, and the second for specific gene confirmation based on target sequences such as anti-EFE or aminocyclopropane cyclase synthase (acc) gene. To ensure the reliability of this method, different kinds of positive and negative controls (such as the probes complementary to cp gene of CaMV) were included in microarray detection system. Four tomato species were identified by means of these methods, and the results indicated that microarray is a high-throughput and more efficient screening method, which could complement PCR-based screening procedures by providing direct conclusive evidence and also may be useful to resolve masking of unknown events by known events.


Assuntos
Microfluídica/instrumentação , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase/métodos , Solanum lycopersicum/genética , Genes de Plantas , Genes Reporter , Regiões Promotoras Genéticas , Regiões Terminadoras Genéticas
18.
Materials (Basel) ; 16(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36837178

RESUMO

The application of Sn-Bi series solder is limited due to the brittleness of Bi phase. Sn-20Bi solder with less Bi element content has great research prospects, but it needs modification to make it a substitute for traditional Sn-Pb solder. In this article, we mixed graphene nanosheets with nanometer Sn powder by means of ultrasonic oscillation, and Sn-20Bi-qGNS (q = 0.01, 0.02, 0.04, 0.06, and 0.1 wt.%) solder alloys were prepared by the melt-casting method. The effects of graphene nanosheets (GNSs) on the microstructure, physical properties, mechanical properties, and corrosion resistance of solder alloys were investigated. Scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to determine the microstructural morphology and composition. The results showed that the melting point, density, and wettability of the solder decreased slightly with the addition of GNSs. The addition of GNSs as a second phase refined the solder structure and improved the tensile strength of the molten Sn-20Bi composite solder to 99.6 MPa, while elongation decreased with the addition of GNSs. Furthermore, GNSs prevented the MC Sn-20Bi-qGNSs/Cu intermetallic compound layers' growth by interfering with atomic diffusion and grain boundary movement. In addition, the addition of 0.02 wt.% GNSs enhanced the shear strength of MC Sn-20Bi solder joints to 46.3 MPa. The electrochemical experimental results show that the surface corrosion products of MC Sn-20Bi-qGNSs under 3.5% NaCl solution were Sn3O(OH)2Cl2, with MC Sn-20Bi-0.01GNSs exhibiting the best corrosion resistance.

19.
Front Vet Sci ; 10: 1144869, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37252387

RESUMO

Monoclonal antibody targeting programmed cell death-1 (PD-1) is one of the most promising treatment therapies for human cancers. Canine PD-1 antibodies used in clinical trials have also shown efficacy in treating canine cancers. An 11-year-old male intact border collie presented to us for evaluation of left cervical mass. Computed tomography (CT) examination revealed an irregular pharyngeal mass invading the surrounding soft tissue. Histological and immunohistochemical results were consistent with a diagnosis of adenocarcinoma, most likely originating from the minor salivary gland. An anti-canine PD-1 monoclonal antibody was administered. Two months after the initial treatment, the tumor reached partial remission and maintained as such for 6 months. Finally, the patient was euthanized due to reasons unrelated to cancer, with a survival time of 316 days. To our knowledge, this is the first report of response to PD-1 blockade treatment in canine adenocarcinoma.

20.
Food Funct ; 14(8): 3641-3658, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36961308

RESUMO

Plasmalogens (Pls), a special group of phospholipids, are effective in ameliorating neurodegenerative disease. In the present study, the metabolic effects of seafood-derived Pls on high fat diet (HFD)-induced hyperlipidemia in zebrafish were evaluated, and the underlying mechanisms of dietary Pls against hyperlipidemia were explored through integrated analyses of hepatic transcriptomics and metabolomics. The results demonstrated that Pls supplementation could effectively alleviate HFD-induced obesity symptoms, such as body weight gain, and decrease total hepatic cholesterol and triglyceride levels. Integrated hepatic transcriptome and metabolome data suggested that Pls mainly altered lipid metabolism pathways (FA metabolism, primary bile acid biosynthesis, steroid hormone biosynthesis, and glycerolipid and glycerophospholipid metabolism) and the TCA cycle, induced the overexpression of anti-oxidation enzymes (Cat, Gpx4, Sod3a and Xdh), reduced disease biomarkers (such as glutarylcarnitine, gamma-glutamyltyrosine, and 11-prostaglandin f2) and gut microbiota-derived metabolites, and increased (±)12(13)-diHOME, EPA, lysoPC and PC levels. Moreover, 5 abnormally regulated metabolites were identified as potential biomarkers associated with hyperlipidemia according to the metabolomics results and suggested the involvement of gut microbiota in the anti-hyperlipidemic effects of Pls. Collectively, these findings suggest that the protective role of Pls is mainly associated with the promotion of unsaturated fatty acid biosynthesis and cholesterol efflux, lipid and phospholipid PUFA remodeling, and anti-oxidation and anti-inflammatory capabilities. This study provides valuable information for reasonably explaining the beneficial effects of seafood-derived Pls in alleviating hyperlipidemia and thus may contribute to the development and application of Pls as functional foods or dietary supplements to protect against obesity and hyperlipidemia.


Assuntos
Hiperlipidemias , Doenças Neurodegenerativas , Animais , Camundongos , Hiperlipidemias/etiologia , Hiperlipidemias/genética , Peixe-Zebra/metabolismo , Dieta Hiperlipídica/efeitos adversos , Plasmalogênios/farmacologia , Transcriptoma , Doenças Neurodegenerativas/metabolismo , Metabolômica/métodos , Fígado/metabolismo , Obesidade/etiologia , Obesidade/genética , Metabolismo dos Lipídeos , Colesterol/metabolismo , Biomarcadores/metabolismo , Camundongos Endogâmicos C57BL
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