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1.
FASEB J ; 36(9): e22473, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35976172

RESUMO

Although the role of serine racemase (SR) in neuropsychiatric disorders has been extensively studied, its role in cell proliferation and differentiation remains unclear. Deletion of Srr, the encoding gene for SR, has been shown to reduce dendritic arborization and dendritic spine density in the brains of adult mice, whereas increased SR levels have been associated with differentiation in cell cultures. Previously, we demonstrated that valproic acid induces differentiation in the N2A neuroblastoma cell line, and that this differentiation is associated with increased SR expression. These observations suggest that SR may have a role in cell proliferation and differentiation. We herein found that both valproic acid and all-trans retinoic acid induced N2A differentiation. In contrast, knockdown of SR reduced levels of differentiation, increased N2A proliferation, promoted cell cycle entry, and modulated expression of cell cycle-related proteins. To further evaluate the effects of SR expression on cell proliferation and differentiation, we used an in vivo model of neuroblastoma in nude mice. N2A cells stably expressing scramble shRNA (Srrwt -N2A) or specific Srr shRNA (Srrkd -N2A) were subcutaneously injected into nude mice. The weights and volumes of Srrwt -N2A-derived tumors were lower than Srrkd -N2A-derived tumors. Furthermore, Srrwt -N2A-derived tumors were significantly mitigated by intraperitoneal injection of valproic acid, whereas Srrkd -N2A-derived tumors were unaffected. Taken together, our findings demonstrate for the first time that alterations in SR expression determine the transition between proliferation and differentiation in neural progenitor cells. Thus, in addition to its well-established roles in neuropsychiatric disorders, our study has highlighted a novel role for SR in cell proliferation and differentiation.


Assuntos
Neuroblastoma , Ácido Valproico , Animais , Diferenciação Celular , Proliferação de Células , Camundongos , Camundongos Nus , Neuroblastoma/genética , Neuroblastoma/metabolismo , RNA Interferente Pequeno/genética , Racemases e Epimerases , Serina , Ácido Valproico/farmacologia
2.
Virol J ; 20(1): 276, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012648

RESUMO

The possibilities of cross-species transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between humans and important livestock species are not yet known. Herein, we used the structural and genetic alignment and surface potential analysis of the amino acid (aa) in angiotensin-converting enzyme 2 (ACE2), tyrosine kinase receptor UFO (AXL), and neuropilin 1 (NRP1) in different species with substantial public health importance. The residues interfacing with the N-terminal domain (NTD) or receptor-binding domain (RBD) of S were aligned to screen the critical aa sites that determined the susceptibility of the SARS-CoV-2 to the host. We found that AXL and NRP1 proteins might be used as the receptors of SARS-CoV-2 in bovines. However, ACE2 protein may not be considered to be involved in the cross-species transmission of SARS-CoV-2 VOCs in cattle because the key residues of the ACE2-S-binding interface were different from those in known susceptible species. This study indicated that emerging SARS-CoV-2 variants potentially expand species tropism to bovines through AXL and NRP1 proteins.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Bovinos , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/genética , COVID-19/veterinária , Neuropilina-1/genética , Neuropilina-1/metabolismo , Ligação Proteica , Receptores Virais/genética , Receptores Virais/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química
3.
Virol J ; 20(1): 196, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644471

RESUMO

BACKGROUND: The possibilities of cross-species transmission of SARS-CoV-2 variants of concern (VOCs) between humans and poultry species are unknown. The analysis of the structure of receptor was used to investigate the potential of emerging SARS-CoV-2 VOCs to expand species tropism to chickens based on the interaction between Spike (S) protein and tyrosine kinase receptor UFO (AXL), angiotensin-converting enzyme 2 (ACE2), and neuropilin 1 (NRP1) with substantial public health importance. METHODS: The structural and genetic alignment and surface potential analysis of the amino acid (aa) in ACE2, AXL, and NRP1 in human, hamster, mouse, mink, ferret, rhesus monkey and chickens were performed by Swiss-Model and pymol software. The critical aa sites that determined the susceptibility of the SARS-CoV-2 to the host were screened by aligning the residues interfacing with the N-terminal domain (NTD) or receptor-binding domain (RBD) of Spike protein. RESULTS: The binding modes of chickens AXL and ACE2 to S protein are similar to that of the ferret. The spatial structure and electrostatic surface potential of NRP1 showed that SARS-CoV-2 VOCs could not invade chickens through NRP1 easily. CONCLUSION: These results suggested that emerging SARS-CoV-2 VOCs potentially expand the host range to chickens mainly through ACE2 and AXL receptors, while NRP1 receptor may rarely participate in the future epidemic of coronavirus disease 2019 in chickens.


Assuntos
COVID-19 , Galinhas , Cricetinae , Animais , Humanos , Camundongos , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/genética , Neuropilina-1/genética , Especificidade de Hospedeiro , Furões , Aminoácidos , Macaca mulatta , Vison
4.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675052

RESUMO

Herpes simplex virus type 1 (HSV-1) is a ubiquitous human pathogen that can cause significant morbidity, primarily facial cold sores and herpes simplex encephalitis. Previous studies have shown that a variety of viruses can reprogram the metabolic profiles of host cells to facilitate self-replication. In order to further elucidate the metabolic interactions between the host cell and HSV-1, we used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to analyze the metabolic profiles in human lung fibroblasts KMB17 infected with HSV-1. The results showed that 654 and 474 differential metabolites were identified in positive and negative ion modes, respectively, and 169 and 114 metabolic pathways that might be altered were screened. These altered metabolites are mainly involved in central carbon metabolism, choline metabolism, amino acid metabolism, purine and pyrimidine metabolism, cholesterol metabolism, bile secretion, and prolactin signaling pathway. Further, we confirmed that the addition of tryptophan metabolite kynurenine promotes HSV-1 replication, and the addition of 25-Hydroxycholesterol inhibits viral replication. Significantly, HSV-1 replication was obviously enhanced in the ChOKα (a choline metabolic rate-limiting enzyme) deficient mouse macrophages. These results indicated that HSV-1 induces the metabolic reprogramming of host cells to promote or resist viral replication. Taken together, these observations highlighted the significance of host cell metabolism in HSV-1 replication, which would help to clarify the pathogenesis of HSV-1 and identify new anti-HSV-1 therapeutic targets.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Interações entre Hospedeiro e Microrganismos , Replicação Viral , Animais , Humanos , Camundongos , Cromatografia Líquida , Herpes Simples/metabolismo , Herpesvirus Humano 1/metabolismo , Espectrometria de Massas em Tandem , Replicação Viral/fisiologia , Metabolômica , Interações entre Hospedeiro e Microrganismos/fisiologia
5.
Mol Med ; 28(1): 23, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35189819

RESUMO

BACKGROUND: The inhibition of osteogenic differentiation is a major factor in glucocorticoid-induced bone loss, but there is currently no effective treatment. Dopamine, a major neurotransmitter, transmits signals via five different seven-transmembrane G protein-coupled receptors termed D1 to D5. Although the relevance of the neuroendocrine system in bone metabolism has emerged, the precise effects of dopamine receptor signaling on osteoblastogenesis remain unknown. METHODS: In vitro, western blotting and immunofluorescence staining were used to observe the expression of dopamine receptors in MC3T3-E1 and BMSCs cells treated with dexamethasone (Dex). In addition, Alizarin red S (ARS) and alkaline phosphatase (ALP) staining and western blotting were used to evaluate the effect of D1R activation on osteogenic differentiation in Dex-induced MC3T3-E1 cells via the ERK1/2 signaling pathway. In vivo, micro-CT and hematoxylin and eosin (H&E), toluidine blue and immunohistochemical staining were used to determine the effect of D1R activation on Dex-induced bone loss. RESULTS: We demonstrated that the trend in D1R but not D2-5R was consistent with that of osteogenic markers in the presence of Dex. We also demonstrated that the activation of D1R promoted Dex-induced osteogenic differentiation by activating the ERK1/2 pathway in vitro. We further demonstrated that a D1R agonist could reduce Dex-induced bone loss, while pretreatment with a D1R inhibitor blocked the effect of a D1R agonist in vivo. CONCLUSIONS: Activation of D1R promotes osteogenic differentiation and reduces Dex-induced bone loss by activating the ERK1/2 pathway. Hence, D1R could serve as a potential therapeutic target for glucocorticoid-induced osteoporosis.


Assuntos
Glucocorticoides , Osteogênese , Diferenciação Celular , Glucocorticoides/efeitos adversos , Sistema de Sinalização das MAP Quinases , Osteoblastos , Transdução de Sinais
6.
Arch Virol ; 166(3): 789-799, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33459883

RESUMO

Hepatitis A virus (HAV), a unique hepatotropic human picornavirus, is the causative agent of acute hepatitis A in humans. Some studies have shown that HAV antagonizes the innate immune response by disrupting interferon-beta (IFN-ß) signaling by viral proteins. However, whether microRNAs (miRNAs), a class of non-coding RNAs, are involved in the antagonism of IFN-ß induction upon HAV infection is still unclear. In this study, we investigated the effects and mechanisms by which HAV-induced miRNAs antagonize IFN-ß signaling. A variety of analytical methods, including miRNA microarray, RT-qPCR, dual-luciferase reporter assay, and Western blotting, were performed using HAV-infected cells. The results indicated that HAV infection upregulates the expression of hsa-miR-146a-5p, which in turn partially suppresses the induction of IFN-ß synthesis, thereby promoting viral replication. Mechanistically, TRAF6 (TNF receptor-associated factor 6), a key adaptor protein in the RIG-I/MDA5-mediated IFN-I signaling pathway, is targeted and degraded by hsa-miR-146a-5p. As TRAF6 is necessary for IFN-ß induction, inhibition of this protein attenuates IFN-ß signaling. Taken together, the results from this study indicated that HAV disrupts RIG-I/MDA5-mediated IFN-I signaling partially through the cleavage of the essential adaptor molecule TRAF6 via hsa-miR-146a-5p.


Assuntos
Vírus da Hepatite A Humana/crescimento & desenvolvimento , Interferon gama/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/genética , Linhagem Celular , Regulação da Expressão Gênica , Hepatite A/patologia , Vírus da Hepatite A Humana/genética , Humanos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Replicação Viral
7.
Virus Genes ; 57(2): 172-180, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33575934

RESUMO

Surveillance of recombinant enterovirus 71 (EV71) and subgenotype replacement is vital for preventing and controlling hand, foot, and mouth disease (HFMD) outbreaks. Despite this, data on recombinant variants and phylogeny of circulating EV71 strains in mainland China are limited. In this study, recombinant variants of EV71 were identified in mainland China from 2009 to 2018. Phylogenetic analysis indicated that except for individual strains (CQ2014-86/CQ/CHN/2014 and EV71/Xiamen/2009 (B5)), almost all of the EV71 strains in mainland China belonged to the subgenotype C4a. Analysing complete genome sequences of 196 EV71 isolates, 3 intertypic recombination strains (VR1432, 30-2/2015/BJ, and Guangdong-2009) and 5 intratypic recombination strains (EV71/P1034/2013, VR1432, Henan-ZMD/CHN/2012, Hubei-WH/CHN/2012, and EV71/P868/2013/China) were identified among naturally circulating EV71. The breakpoints of these recombinant strains were located within the P1, P2, and P3 encoding regions. Notably, a double recombinant (VR1432) resulting from recombination between EV71 subgenotype C4a and C4b strain SHZH98 and a CA8 strain Donovan was identified. This study reports these specific intertypic and intratypic recombination events for the first time highlighting the importance of genetic recombination in the emergence of new enterovirus variants.


Assuntos
Enterovirus Humano A/genética , Infecções por Enterovirus/virologia , Genoma Viral , China , Enterovirus Humano A/classificação , Enterovirus Humano A/isolamento & purificação , Evolução Molecular , Humanos , Recombinação Genética
8.
Cell Physiol Biochem ; 47(5): 2031-2045, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29972822

RESUMO

BACKGROUND/AIMS: Circular RNAs (circRNAs), a new class of regulators of gene expression, are involved in diverse physiological and pathogenic processes. However, their role in cellular responses to virus infection is yet unclear. METHODS: A human lung fibroblast cell line was infected or mock infected by herpes simplex virus 1 (HSV-1). Deep RNA sequencing was used to profile the global changes in circRNAs, genes, and miRNAs following HSV-1 infection. Altered circRNAs, genes, and miRNAs were validated using quantitative reverse transcription polymerase chain reaction (RT-qPCR). An integration analysis of circRNAs, genes, and miRNAs was applied to investigate the putative function of the dysregulated circRNAs. RESULTS: A total of 536 circRNAs, 3,885 genes, and 207 miRNAs were significantly dysregulated after HSV-1 infection. An integration analysis of circRNAs, genes, and miRNAs revealed the alleged involvement of dysregulated circRNAs in cellular responses to HSV-1 infection via the circRNA-miRNA-gene regulatory axis. These genes regulated by circRNAs were enriched to NOD-like receptor/JAK-STAT signaling pathway, and pathways of apoptosis, cell cycle progression, and cell death, all of which may be implicated in the viral pathogenesis and cellular immunity. CONCLUSIONS: These data present a comprehensive view for circRNAs induced by HSV-1 and their interplay with miRNAs and genes during HSV-1 infection, thus offering new insights into the mechanisms of interactions between HSV-1 and the host.


Assuntos
Herpes Simples/metabolismo , Herpesvirus Humano 1/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , RNA/metabolismo , Transdução de Sinais , Linhagem Celular , Fibroblastos , Herpes Simples/genética , Herpesvirus Humano 1/genética , Humanos , RNA/genética
9.
Virol J ; 15(1): 131, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30126417

RESUMO

BACKGROUND: Dengue is the most common mosquito-borne infection worldwide and a serious threat to global public health. Sporadic dengue virus serotype 2 (DENV-2) imported cases from Myanmar have been documented almost every year in Yunnan Province of China since 2005. However, the complete genome sequences of DENV-2 isolates imported from Myanmar are not available. METHODS: The full-length genome of the DENV-2 strain (YNPE2), isolated from an imported case from Myanmar in 2013, was identified by the next-generation sequencing. The extreme ends of the viral genome were validated by 5'/3' RACE and Sanger sequencing. Furthermore, phylogenetic, recombination and selection pressure analyses were conducted for the molecular characterization of YNPE2 strain. RESULTS: Whole-genome sequencing revealed that the full-length sequence of YNPE2 strain was 10,724 bases, with an open reading frame encoding for 3391 amino acids. The YNPE2 strain had 99.0% nucleotide identity and 99.8% amino acid identity with two closely related strains, ThD2_0078_01 strain (DQ181797) and DENV-2/TH/BID-V2157/200 strain (FJ639832). The phylogenetic analysis suggested that the YNPE2 strain belonged to Asian I genotype and was likely derived from Thailand strain (DQ181797). Moreover, selection pressure analysis revealed two amino acid sites of the NS4B and NS5 proteins, with important evidence of positive selection. CONCLUSION: This study revealed the first complete genome sequence and molecular characterization of a DENV-2 strain (YNPE2) isolated from an imported case from Myanmar, thus providing a valuable reference genome source for future surveillance, epidemiology and vaccine development of DENV-2 virus in Yunnan, China.


Assuntos
Doenças Transmissíveis Importadas/virologia , Vírus da Dengue/genética , Dengue/virologia , Genoma Viral , Sorogrupo , Adulto , Vírus da Dengue/isolamento & purificação , Feminino , Genótipo , Humanos , Mianmar , Fases de Leitura Aberta , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência
10.
Virol J ; 15(1): 113, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-30041666

RESUMO

BACKGROUND: Dengue virus (DENV) infection caused by international visitors has become a public health concern in China. Although sporadic imported cases of DENV have been documented in Yunnan, China since 2000, a complete genome sequence of dengue virus serotype 3 (DENV-3) imported from Laos is still not available. Here, we report the first complete genome sequence and genomic characterization of a DENV-3 strain (YNPE3) isolated from a patient returned from Laos. METHODS: Viral isolation from the patient's serum was performed using mosquitoes C6/36 cells. Reverse transcriptase polymerase chain reaction (RT-PCR) was used for identification and serotyping of the virus. The complete sequence was determined by Sanger dideoxy sequencing. Homology analysis was implemented by NCBI-BLAST. Multiple sequence alignment was performed using MegAlign module of the Lasergene 7 software package DNASTAR. MFOLD software was used to predict the RNA secondary structure of 5' untranslated region (UTR) and 3' UTR. Phylogenetic analysis, which was based on envelope gene and complete coding sequence, was performed by Maximum-Likelihood method. RESULTS: RT-PCR analysis confirmed that the virus belonged to dengue virus serotype 3, which was named YNPE3 strain. The full-length genome of the YNPE3 strain was 10,627 nucleotides (nts) with an open reading frame (ORF) encoding 3390 amino acids. Strain YNPE3 shared 98.6-98.8% nucleotide identity with the closely related strains isolated in India (JQ922556, KU216209, KU216208). We observed the deletion of about 40 nts in the 5' UTR and 3' UTR of strain YNPE3, and 11 nts (ACGCAGGAAGT) insertion that was present in the 3' UTR of YNPE3. Compared with prototype strain H87, abundant amino acid substitutions in the YNPE3 strain were observed. Phylogenetic analysis revealed that the YNPE3 strain belonged to genotype III of DENV-3, and that it might be closely related with genotype III strains isolated in Laos and India. CONCLUSIONS: This is the first report of the complete genome sequence and molecular characterization of a DENV-3 isolate imported from Laos. The presented results can further promote disease surveillance, and epidemiological and evolutionary studies of the DENV-3 in Yunnan province of China.


Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/genética , Dengue/virologia , Filogenia , Doença Relacionada a Viagens , Viagem , Substituição de Aminoácidos , Animais , Linhagem Celular , Criança , China/epidemiologia , Dengue/diagnóstico , Dengue/transmissão , Vírus da Dengue/isolamento & purificação , Genoma Viral , Humanos , Laos , Mutação , Conformação de Ácido Nucleico , RNA Viral/química , RNA Viral/genética , Sorogrupo
11.
Arch Virol ; 163(10): 2903-2906, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29948381

RESUMO

The epidemic of dengue virus infections has spread markedly in Yunnan province of China in recent years due to an increase in the number of imported dengue cases. To the best of our knowledge, the present study is the first to report a whole genome sequence and molecular characterization of an imported DENV-4 isolate from Thailand. The current strain, 2013JH285, has an RNA genome of 10,772 nucleotides that shares 99.0% nucleotide and 99.7% amino acid sequence identity with the 2013 Thailand strain CTI2-13. Phylogenetic analysis of the whole genome sequence revealed that the 2013JH285 strain belongs to genotype I of DENV-4. Recombination analysis suggested that the 2013JH285 strain originated from inter-genotypic recombination of DENV-4 strains. The new complete DENV-4 genome sequence reported here might contribute to further understanding of the molecular epidemiology and disease surveillance of DENV-4 in China.


Assuntos
Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Animais , Linhagem Celular , China , Vírus da Dengue/classificação , Genoma Viral , Genótipo , Humanos , Filogenia , Sorogrupo , Tailândia , Viagem
12.
Med Sci Monit ; 23: 4932-4938, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29032381

RESUMO

BACKGROUND To evaluate the correlation between vertebral endplate change and the level of lumbar disc degeneration via magnetic resonance imaging (MRI). MATERIAL AND METHODS A total of 345 patients who were recruited from our hospital from May 2012 to May 2016 were evaluated for the presence of intervertebral disc degeneration or herniation. The degree of degeneration was assessed according to Pfirrmann grade. Vertebral endplate change was evaluated based on the endplate concave angle (ECA), and Modic change on sagittal MRI. The correlation between ECA and lumbar disc degeneration or Modic change and lumbar disc degeneration was analyzed. RESULTS The results showed that there was no statistically significant difference in comparison of the ECAs in adjacent L3-5 vertebra between males and females. With the aggravation in degenerative changes of L3-5 discs, the ECAs of adjacent L3 superior endplate, L4 inferior and superior endplates and L5 inferior endplate were gradually enlarged, indicating the positive correlation between the lumbar disc degeneration and ECAs. The rate of Modic change in females was higher than that in males without a statistically significant difference. Area of Modic change was positively correlated with the degree of lumbar disc degeneration. Additionally, we also identified the positive correlation between the rate of Modic change and the degree of lumbar disc degeneration. CONCLUSIONS Endplate angle and lumbar disc degeneration are positively correlated. The endplates and endplate signal changes can reflect the degree of disc degeneration and Modic changes can reflect the rate of clinical lumbar disc degeneration degree.


Assuntos
Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Adulto , Idoso , Feminino , Hospitais , Humanos , Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/patologia , Dor Lombar/patologia , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
13.
Virus Genes ; 52(3): 317-24, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26936379

RESUMO

The establishment of persistent infection with hepatitis A virus (HAV) is the common result of most HAV/cell culture systems. Previous observations show that the synthesis of viral RNAs is reduced during infection. However, the underlying mechanism is poorly understood. We characterized three HAV-encoded miRNAs in our previous study. In this study, we aim to investigate the impact of these miRNAs on the accumulation of viral RNAs. The results indicated that the synthesis of viral genomic RNAs was dramatically reduced (more than 75 % reduction, P < 0.05) when transfected with one or two viral miRNA mimics. Conversely, they were significantly increased (more than 3.3-fold addition, P < 0.05) when transfected with one or two viral miRNA inhibitors. The luciferase reporter assay of miRNA targets showed that viral miRNAs were fully complementary to specific sites of the viral plus or minus strand RNA and strongly inhibited their expressions. Further data showed that the relative abundance of viral genomic RNA fragments that contain miRNA targets was also dramatically reduced (more than 80 % reduction, P < 0.05) when viral miRNAs were overexpressed with miRNA mimics. In contrast, they were significantly increased (approximately 2-fold addition, P < 0.05) when viral miRNAs were inhibited with miRNA inhibitors. In conclusion, these data suggest a possible mechanism for the reduction of viral RNA synthesis during HAV infection. Thus, we propose that it is likely that RNA virus-derived miRNA could serve as a self-mediated feedback regulator during infection.


Assuntos
Vírus da Hepatite A/genética , Hepatite A/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Viral/genética , Vírion/metabolismo , Linhagem Celular , Perfilação da Expressão Gênica , Inativação Gênica , Genoma Viral , Hepatite A/virologia , Vírus da Hepatite A/metabolismo , Humanos , MicroRNAs/biossíntese , RNA Viral/análise , RNA Viral/metabolismo , Transfecção , Vírion/genética , Vírion/crescimento & desenvolvimento
14.
FASEB J ; 28(10): 4381-93, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25002121

RESUMO

MicroRNAs (miRNAs), including host miRNAs and viral miRNAs, play vital roles in regulating host-virus interactions. DNA viruses encode miRNAs that regulate the viral life cycle. However, it is generally believed that cytoplasmic RNA viruses do not encode miRNAs, owing to inaccessible cellular miRNA processing machinery. Here, we provide a comprehensive genome-wide analysis and identification of miRNAs that were derived from hepatitis A virus (HAV; Hu/China/H2/1982), which is a typical cytoplasmic RNA virus. Using deep-sequencing and in silico approaches, we identified 2 novel virally encoded miRNAs, named hav-miR-1-5p and hav-miR-2-5p. Both of the novel virally encoded miRNAs were clearly detected in infected cells. Analysis of Dicer enzyme silencing demonstrated that HAV-derived miRNA biogenesis is Dicer dependent. Furthermore, we confirmed that HAV mature miRNAs were generated from viral miRNA precursors (pre-miRNAs) in host cells. Notably, naturally derived HAV miRNAs were biologically and functionally active and induced post-transcriptional gene silencing (PTGS). Genomic location analysis revealed novel miRNAs located in the coding region of the viral genome. Overall, our results show that HAV naturally generates functional miRNA-like small regulatory RNAs during infection. This is the first report of miRNAs derived from the coding region of genomic RNA of a cytoplasmic RNA virus. These observations demonstrate that a cytoplasmic RNA virus can naturally generate functional miRNAs, as DNA viruses do. These findings also contribute to improved understanding of host-RNA virus interactions mediated by RNA virus-derived miRNAs.


Assuntos
Vírus da Hepatite A/genética , Hepatite A/metabolismo , MicroRNAs/metabolismo , RNA Viral/metabolismo , Sequência de Bases , Linhagem Celular , Inativação Gênica , Vírus da Hepatite A/metabolismo , Humanos , MicroRNAs/química , MicroRNAs/genética , Dados de Sequência Molecular , Precursores de RNA/genética , Precursores de RNA/metabolismo , RNA Viral/química , RNA Viral/genética , Ribonuclease III/genética , Ribonuclease III/metabolismo
15.
Virol J ; 11: 121, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24981144

RESUMO

BACKGROUND: It is generally believed that RNA virus replicating in the cell cytoplasm would not encode microRNAs (miRNAs) due to nucleus inaccessibility. Recent studies have described cytoplasmic RNA virus genome-derived miRNAs in West Nile virus (WNV) and Dengue virus (DENV). However, naturally occurring miRNAs derived from the antigenome of a cytoplasmic RNA virus have not been described. METHODS: Hepatitis A virus (HAV) was served as a model virus to investigate whether the antigenome of a cytoplasmic RNA virus would be processed into miRNAs or miRNA-like small RNAs upon infection. HAV antigenome was queried for putative miRNA precursors (pre-miRNA) with the VMir analyzer program. Mature miRNA prediction was performed using MatureBayes and Bayes-SVM-MiRNA web server v1.0. Finally, multiple experimental approaches, including cloning and sequencing-, RNAi-, plasmid-based miRNA expression- and luciferase reporter assays, were performed to identify and validate naturally occurring viral antigenome-derived miRNAs. RESULTS: Using human HAV genotype IA (isolate H2) (HAVH2), a virally encoded miRNA-like small RNA was detected on the antigenome and named hav-miR-N1-3p. Transcription of viral pre-miRNA in KMB17 and HEK293T cells led to mature hav-miR-N1-3p production. In addition, silencing of the miRNA-processing enzyme Dicer or Drosha caused a dramatic reduction in miRNA levels. Furthermore, artificial target of hav-miR-N1-3p was silenced by synthesized viral miRNA mimics and the HAVH2 naturally-derived hav-miR-N1-3p. CONCLUSION: These results suggested that the antigenome of a cytoplasmic RNA virus could be processed into functional miRNAs. Our findings provide new evidence supporting the hypothesis that cytoplasmic RNA viruses naturally encode miRNAs through cellular miRNA processing machinery.


Assuntos
Genoma Viral , Vírus da Hepatite A/genética , MicroRNAs/genética , RNA Viral/genética , Linhagem Celular , Biologia Computacional , Humanos , MicroRNAs/metabolismo , RNA Viral/metabolismo
16.
Vaccine ; 42(18): 3883-3898, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38777697

RESUMO

BACKGROUND: Community-acquired pneumonia often stems from the macrolide-resistant strain of Mycoplasma pneumoniae, yet no effective vaccine exists against it. METHODS: This study proposes a vaccine-immunoinformatics strategy for Mycoplasma pneumoniae and other pathogenic microbes. Specifically, dominant B and T cell epitopes of the Mycoplasma pneumoniae P30 adhesion protein were identified through immunoinformatics method. The vaccine sequence was then constructed by coupling with CTLA-4 extracellular region, a novel molecular adjuvant for antigen-presenting cells. Subsequently, the vaccine's physicochemical properties, antigenicity, and allergenicity were verified. Molecular dynamics modeling was employed to confirm interaction with TLR-2, TLR-4, B7-1, and B7-2. Finally, the vaccine underwent in silico cloning for expression. RESULTS: The vaccine exhibited both antigenicity and non-allergenicity. Molecular dynamics simulation, post-docking with TLR-2, TLR-4, B7-1, and B7-2, demonstrated stable interaction between the vaccine and these molecules. In silico cloning confirmed effective expression of the vaccine gene in insect baculovirus vectors. CONCLUSION: This vaccine-immunoinformatics approach holds promise for the development of vaccines against Mycoplasma pneumoniae and other pathogenic non-viral and non-bacterial microbes.


Assuntos
Vacinas Bacterianas , Antígeno CTLA-4 , Biologia Computacional , Epitopos de Linfócito B , Epitopos de Linfócito T , Mycoplasma pneumoniae , Pneumonia por Mycoplasma , Mycoplasma pneumoniae/imunologia , Mycoplasma pneumoniae/genética , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/genética , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito B/genética , Humanos , Biologia Computacional/métodos , Pneumonia por Mycoplasma/prevenção & controle , Pneumonia por Mycoplasma/imunologia , Antígeno CTLA-4/imunologia , Simulação de Dinâmica Molecular , Simulação de Acoplamento Molecular , Receptor 2 Toll-Like/imunologia , Imunoinformática
17.
Comput Biol Med ; 175: 108533, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38714050

RESUMO

Bone proliferation is an important pathological feature of inflammatory rheumatic diseases. Although recent advance in high-resolution peripheral quantitative computed tomography (HR-pQCT) enables physicians to study microarchitectures, physicians' annotation of proliferation suffers from slice inconsistency and subjective variations. Also, there are only few effective automatic or semi-automatic tools for proliferation detection. In this study, by integrating pathological knowledge of proliferation formation with the advancement of statistical shape analysis theory, we present an unsupervised method, named Deformation-Controllable Elastic Shape model, for 3D bone Proliferation Analysis (DCES-PA). Unlike previous shape analysis methods that directly regularize the smoothness of the displacement field, DCES-PA regularizes the first and second-order derivative of the displacement field and decomposes these vector fields according to different deformations. For the first-order elastic metric, DCES-PA orthogonally decomposes the first-order derivative of the displacement field by shearing, scaling and bending deformation, and then penalize deformations triggering proliferation formation. For the second-order elastic metric, DCES-PA encodes both intrinsic and extrinsic surface curvatures into the second-order derivative of the displacement field to control the generation of high-curvature regions. By integrating the elastic shape metric with the varifold distances, DCES-PA achieves correspondence-free shape analysis. Extensive experiments on both simulated and real clinical datasets demonstrate that DCES-PA not only shows an improved accuracy than other state-of-the-art shape-based methods applied to proliferation analysis but also produces highly sensitive proliferation annotations to assist physicians in proliferation analysis.


Assuntos
Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Imageamento Tridimensional/métodos , Osso e Ossos/diagnóstico por imagem , Mãos/diagnóstico por imagem , Feminino , Masculino , Proliferação de Células
18.
J Immunol ; 186(1): 563-75, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21131419

RESUMO

Heat shock protein 90 (Hsp90) is a molecular chaperone involved in folding and stabilizing multiple intracellular proteins that have roles in cell activation and proliferation. Many Hsp90 client proteins in tumor cells are mutated or overexpressed oncogenic proteins driving cancer cell growth, leading to the acceptance of Hsp90 as a potential therapeutic target for cancer. Because several signal transduction molecules that are dependent on Hsp90 function are also involved in activation of innate and adaptive cells of the immune system, we investigated the mechanism by which inhibiting Hsp90 leads to therapeutic efficacy in rodent models of inflammation and autoimmunity. EC144, a synthetic Hsp90 inhibitor, blocked LPS-induced TLR4 signaling in RAW 264.7 cells by inhibiting activation of ERK1/2, MEK1/2, JNK, and p38 MAPK but not NF-κB. Ex vivo LPS-stimulated CD11b(+) peritoneal exudate cells from EC144-treated mice were blocked from phosphorylating tumor progression locus 2, MEK1/2, and ERK1/2. Consequently, EC144-treated mice were resistant to LPS administration and had suppressed systemic TNF-α release. Inhibiting Hsp90 also blocked in vitro CD4(+) T cell proliferation in mouse and human MLRs. In vivo, semitherapeutic administration of EC144 blocked disease development in rat collagen-induced arthritis by suppressing the inflammatory response. In a mouse collagen-induced arthritis model, EC144 also suppressed disease development, which correlated with a suppressed Ag-specific Ab response and a block in activation of Ag-specific CD4(+) T cells. Our results describe mechanisms by which blocking Hsp90 function may be applicable to treatment of autoimmune diseases involving inflammation and activation of the adaptive immune response.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Doenças Autoimunes/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Imunidade Inata/efeitos dos fármacos , Imunossupressores/farmacologia , Mediadores da Inflamação/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Linhagem Celular , Linhagem Celular Transformada , Cristalografia por Raios X , Modelos Animais de Doenças , Feminino , Humanos , Imunossupressores/química , Imunossupressores/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/metabolismo , Mediadores da Inflamação/síntese química , Mediadores da Inflamação/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Pirimidinas/síntese química , Pirimidinas/uso terapêutico , Pirróis/síntese química , Pirróis/uso terapêutico , Ratos
19.
Sci Rep ; 13(1): 15070, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700027

RESUMO

Chlamydia pneumoniae (C. pneumoniae) infection in humans is universal and causes various respiratory infectious diseases, making a safe and effective preventive vaccine essential. In this study, a multi-epitope vaccine with CTLA-4 extracellular structure was constructed by an immunoinformatics approach. Since MOMP protein is the major extracellular protein in C. pneumoniae and has good immunogenicity and high conservation, we selected the MOMP protein of C. pneumoniae as the antigen target, predicted the T and B cell epitopes of the MOMP protein and then connected the CTLA-4 extracellular structure with the predicted dominant epitopes by various linkers to construct a multi-epitope vaccine. The biochemical characterization of the multi-epitope vaccine showed its immunogenicity and anti-allergic properties. The tertiary structure of this vaccine, along with molecular docking, molecular dynamics simulation, and principal component analysis, showed that the multi-epitope vaccine structure interacted with B7 (B7-1, B7-2) and toll-like receptors (TLR-2, TLR-4). Ultimately, the vaccine was cloned and effectively expressed in silico on an insect baculovirus expression vector (pFastBac1). These analyses showed that the designed vaccine could potentially target antigen-presenting cells and was immune to C. pneumoniae, which provided novel strategies for developing the vaccine.


Assuntos
Chlamydophila pneumoniae , Vacinas , Humanos , Antígeno CTLA-4 , Simulação de Acoplamento Molecular , Epitopos de Linfócito B
20.
Stat Methods Med Res ; 32(7): 1338-1360, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37161735

RESUMO

For clinical studies with continuous outcomes, when the data are potentially skewed, researchers may choose to report the whole or part of the five-number summary (the sample median, the first and third quartiles, and the minimum and maximum values) rather than the sample mean and standard deviation. In the recent literature, it is often suggested to transform the five-number summary back to the sample mean and standard deviation, which can be subsequently used in a meta-analysis. However, if a study contains skewed data, this transformation and hence the conclusions from the meta-analysis are unreliable. Therefore, we introduce a novel method for detecting the skewness of data using only the five-number summary and the sample size, and meanwhile, propose a new flow chart to handle the skewed studies in a different manner. We further show by simulations that our skewness tests are able to control the type I error rates and provide good statistical power, followed by a simulated meta-analysis and a real data example that illustrate the usefulness of our new method in meta-analysis and evidence-based medicine.


Assuntos
Medicina Baseada em Evidências , Tamanho da Amostra
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