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1.
J Immunol ; 209(7): 1237-1242, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36165199

RESUMO

IL-9, produced mainly by specialized T cells, mast cells, and group 2 innate lymphoid cells, regulates immune responses, including anti-helminth and allergic responses. Polarization of naive CD4 T cells into IL-9-producing T cells (Th9s) is induced by IL-4 and TGF-ß1 or IL-1ß. In this article, we report that the transcription factor growth factor-independent 1 transcriptional repressor (GFI1) plays a negative role in mouse Th9 polarization. Moreover, the expression of GFI1 is controlled by liganded RARα, allowing GFI1 to mediate the negative effect of retinoic acid on IL-9 expression. The Gfi1 gene has multiple RARα binding sites in the promoter region for recruiting nuclear coactivator steroid receptor coactivator-3 and p300 for histone epigenetic modifications in a retinoic acid-dependent manner. Retinoic acid-induced GFI1 binds the Il9 gene and suppresses its expression. Thus, GFI1 is a novel negative regulator of Il9 gene expression. The negative GFI1 pathway for IL-9 regulation provides a potential control point for Th9 activity.


Assuntos
Interleucina-9 , Receptores de Esteroides , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Histonas/metabolismo , Imunidade Inata , Interleucina-4/metabolismo , Linfócitos/metabolismo , Camundongos , Receptores de Esteroides/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Tretinoína/metabolismo
2.
Biom J ; 66(1): e2200348, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38240577

RESUMO

An inference procedure is proposed to provide consistent estimators of parameters in a modal regression model with a covariate prone to measurement error. A score-based diagnostic tool exploiting parametric bootstrap is developed to assess adequacy of parametric assumptions imposed on the regression model. The proposed estimation method and diagnostic tool are applied to synthetic data generated from simulation experiments and data from real-world applications to demonstrate their implementation and performance. These empirical examples illustrate the importance of adequately accounting for measurement error in the error-prone covariate when inferring the association between a response and covariates based on a modal regression model that is especially suitable for skewed and heavy-tailed response data.


Assuntos
Simulação por Computador
3.
Molecules ; 29(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38998960

RESUMO

The United Nations proposed the Sustainable Development Goals with the aim to make human settlements in cities resilient and sustainable. The excessive discharge of urban waste including sludge and garden waste can pollute groundwater and lead to the emission of greenhouse gases (e.g., CH4). The proper recycling of urban waste is essential for responsible consumption and production, reducing environmental pollution and addressing climate change issues. This study aimed to prepare biochar with high adsorption amounts of iodine using urban sludge and peach wood from garden waste. The study was conducted to examine the variations in the mass ratio between urban sludge and peach wood (2/1, 1/1, and 1/2) as well as pyrolysis temperatures (300 °C, 500 °C, and 700 °C) on the carbon yield and adsorption capacities of biochar. Scanning electron microscopy, Brunauer-Emmett-Teller analysis, Fourier transform infrared spectrometry, powder X-ray diffraction, and elemental analysis were used to characterize the biochar produced at different pyrolysis temperatures and mass ratios. The results indicate that the carbon yield of biochar was found to be the highest (>60%) at a pyrolysis temperature of 300 °C across different pyrolysis temperatures. The absorbed amounts of iodine in the aqueous solution ranged from 86 to 223 mg g-1 at a mass ratio of 1:1 between urban sludge and peach wood, which were comparably higher than those observed in other mass ratios. This study advances water treatment by offering a cost-effective method by using biochar derived from the processing of urban sludge and garden waste.


Assuntos
Carvão Vegetal , Iodo , Pirólise , Esgotos , Carvão Vegetal/química , Iodo/química , Esgotos/química , Adsorção , Temperatura , Jardins , Espectroscopia de Infravermelho com Transformada de Fourier , Cidades
4.
Arch Virol ; 168(6): 164, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209311

RESUMO

An outbreak of COVID-19 in Shanghai, China, in March 2022 was caused by the Omicron variant. The epidemic lasted for more than 3 months, and the cumulative number of infected people reached 626,000. We investigated the impact of clinical factors on disease outcomes in patients with COVID-19. Using a case-control study design, we examined cases from fever clinics with confirmed Omicron variant infection, analyzed their population and laboratory diagnostic characteristics, and provided theoretical support for subsequent epidemic prevention and control. Logistic regression was used to identify factors associated with infection with the Omicron variant. The results of this study show that the COVID-19 vaccine can protect against infection with the Omicron variant, and more than 50% of infected people had not been vaccinated. Compared with the epidemic in Wuhan 2 years ago, most of the patients in the hospital in the Shanghai epidemic had underlying diseases (P = 0.006). A comparison of patients infected with the Omicron variant in Shanghai and patients with other respiratory tract infections showed no significant difference in the levels of neutrophils, lymphocytes, eosinophils, white blood cells, hemoglobin, or platelets (P > 0.05). People over 60 years old and those with underlying diseases were at risk for pneumonia (OR = 14.62 (5.49-38.92), P < 0.001; OR = 5.29 (2.58-10.85), P < 0.001, respectively), but vaccination was a protective factor (OR = 0.24 (0.12-0.49), P < 0.001). In summary, vaccination has a potential effect on infection with Omicron variant strains and provides protection against pneumonia. The severity of illness caused by the Omicron variant in 2022 was significantly lower than that of the original SARS-CoV-2 variant from two years previously.


Assuntos
COVID-19 , Humanos , Pessoa de Meia-Idade , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinas contra COVID-19 , Estudos de Casos e Controles , China/epidemiologia
5.
Arch Sex Behav ; 52(7): 2881-2896, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37154880

RESUMO

Early sexual intercourse is associated with sexually transmitted infections, pregnancy, and depressive symptoms, and delay of intercourse allows adolescents opportunities to practice relationship skills (Coker et al., 1994; Harden, 2012; Kugler et al., 2017; Spriggs & Halpern, 2008). Thus, understanding predictors of early sexual intercourse is crucial. Prior research has suggested that violence exposure is associated with early initiation of sexual intercourse in adolescence (Abajobir et al., 2018; Orihuela et al., 2020). However, most studies have looked only at a single type of violence exposure. In addition, little research has examined longitudinal patterns of violence exposure in order to determine whether there are particular periods when the violence exposure may have the strongest impact on sexual behavior. Guided by life history and cumulative disadvantage theories, we use longitudinal latent class analysis and data from the Future of Families and Child Well-being Study (N = 3,396; 51.1% female, 48.9% male) to examine how longitudinal patterns of multiple types of violence exposures across ages 3 to 15 are associated with early sexual initiation in adolescence. Findings suggest that experiencing persistent physical and emotional abuse across childhood was associated with the greatest prevalence of early sexual initiation. Early exposure to violence was not consistently associated with greater likelihood of sexual initiation; instead, early abuse was more strongly associated with sexual initiation for boys, while late childhood abuse was more strongly associated for girls. These findings suggest that gender-sensitive programs are highly needed to address unique risk factors for boys' and girls' sexual behaviors.


Assuntos
Comportamento do Adolescente , Maus-Tratos Infantis , Exposição à Violência , Infecções Sexualmente Transmissíveis , Gravidez , Humanos , Masculino , Criança , Feminino , Adolescente , Exposição à Violência/psicologia , Comportamento Sexual , Violência , Maus-Tratos Infantis/psicologia
6.
Pharm Stat ; 22(2): 349-364, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36418025

RESUMO

Unblinded sample size re-estimation (SSR) is often planned in a clinical trial when there is large uncertainty about the true treatment effect. For Proof-of Concept (PoC) in a Phase II dose finding study, contrast test can be adopted to leverage information from all treatment groups. In this article, we propose two-stage SSR designs using frequentist conditional power (CP) and Bayesian predictive power (PP) for both single and multiple contrast tests. The Bayesian SSR can be implemented under a wide range of prior settings to incorporate different prior knowledge. Taking the adaptivity into account, all type I errors of final analysis in this paper are rigorously protected. Simulation studies are carried out to demonstrate the advantages of unblinded SSR in multi-arm trials.


Assuntos
Projetos de Pesquisa , Humanos , Tamanho da Amostra , Teorema de Bayes , Simulação por Computador , Incerteza
7.
Mod Rheumatol ; 33(1): 111-121, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35141748

RESUMO

OBJECTIVE: This study aimed to investigate the linkage of long non-coding RNA (lncRNA) expression profile with etanercept response in rheumatoid arthritis (RA) patients. METHODS: Peripheral blood mononuclear cell (PBMC) samples were collected from 80 RA patients prior to etanercept treatment. Samples from eight responders and eight non-responders at week 24 (W24) were proposed to RNA-sequencing, then 10 candidate lncRNAs were sorted and their PBMC expressions were validated by reverse transcription quantitative chain reaction (RT-qPCR) in 80 RA patients. Subsequently, clinical response by lncRNA (CRLnc) prediction model was established. RESULTS: RNA-sequencing identified 254 up-regulated and 265 down-regulated lncRNAs in W24 responders compared with non-responders, which were enriched in immune or joint related pathways such as B-cell receptor signaling, osteoclast differentiation and T-cell receptor signaling pathways, etc. By reverse transcription quantitative chain reaction (RT-qPCR) validation: Two lncRNAs were correlated with W4 response, three lncRNAs were correlated with W12 response, seven lncRNAs were correlated with W24 response. Subsequently, to construct and validate CRLnc prediction model, 80 RA patients were randomly divided into test set (n = 40) and validation set (n = 40). In the test set, lncRNA RP3-466P17.2 (OR = 9.743, P = .028), RP11-20D14.6 (OR = 10.935, P = .007), RP11-844P9.2 (OR = 0.075, P = .022), and TAS2R64P (OR = 0.044, P = .016) independently related to W24 etanercept response; then CRLnc prediction model integrating these four lncRNAs presented a good value in predicting W24 etanercept response (Area Under Curve (AUC): 0.956, 95%CI: 0.896-1.000). However, in the validation set, the CRLnc prediction model only exhibited a certain value in predicting W24 etanercept response (AUC: 0.753, 95%CI: 0.536-0.969). CONCLUSIONS: CRLnc prediction model is potentially a useful tool to instruct etanercept treatment in RA patients.


Assuntos
Artrite Reumatoide , RNA Longo não Codificante , Humanos , Etanercepte/farmacologia , Etanercepte/uso terapêutico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Longo não Codificante/uso terapêutico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Leucócitos Mononucleares/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética
8.
J Clin Lab Anal ; 36(1): e24111, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34811816

RESUMO

BACKGROUND: Dual specificity phosphatase 22 (DUSP22), also named as Jun N-terminal kinase pathway associated phosphatase recently, is reported to be closely engaged in immune and inflammation regulation. This study aimed to investigate the interaction between synovium DUSP22 and serum DUSP22 levels and to explore their correlation with rheumatoid arthritis (RA) risk, inflammation, and disease activity. METHODS: Synovium and serum samples from 42 RA patients with knee involvement underwent arthroscopy, and 20 knee trauma patients were collected. Besides, serum samples from 40 healthy controls were also obtained. Synovium DUSP22 expression was detected by reverse transcription quantitative polymerase chain reaction, while serum DUSP22 level was detected by enzyme-linked immunosorbent assay. RESULTS: Synovium DUSP22 level was greatly decreased in RA patients compared to trauma controls (p < 0.001), and it was negatively correlated with tender joint count (TJC) (r = -0.318, p = 0.040), C-reactive protein (CRP) (r = -0.330, p = 0.033), and Lysholm score (r = -0.423, p = 0.005) in RA patients. Serum DUSP22 level was lowest in RA patients, followed by trauma controls, then highest in healthy controls (p < 0.001). Serum DUSP22 level was negatively associated with TJC (r = -0.438, p = 0.004), swollen joint count (SJC) (r = -0.372, p = 0.015), CRP (r = -0.391, p = 0.011), and disease activity score in 28 joints (DAS28ESR ) score (r = -0.406, p = 0.008), and it increased after treatment (p = 0.001) in RA patients. In addition, serum DUSP22 level positively related to synovium DUSP22 level in RA patients (r = 0.394, p = 0.010). CONCLUSION: Synovium and serum DUSP22 are intercorrelated and insufficiently expressed in RA patients; meanwhile, their deficiency correlates with increased systemic inflammation, disease activity, and joint dysfunction.


Assuntos
Artrite Reumatoide , Fosfatases de Especificidade Dupla/análise , Fosfatases da Proteína Quinase Ativada por Mitógeno/análise , Membrana Sinovial/química , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/metabolismo , Biomarcadores/análise , Biomarcadores/sangue , Fosfatases de Especificidade Dupla/sangue , Fosfatases de Especificidade Dupla/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatases da Proteína Quinase Ativada por Mitógeno/sangue , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo
9.
Environ Toxicol ; 37(4): 720-729, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34897960

RESUMO

Autophagy is a regulatory mechanism involved in cadmium (Cd)-induced bone toxicity and is suppressed by various stimuli, including oxidative stress. Puerarin is an isoflavonoid compound isolated from Pueraria, a plant used in traditional Chinese medicine. The underlying mechanisms of action of puerarin remain unclear. The objective of this study was to explore the mitigating effects of puerarin on cadmium-induced oxidative damage in the bones of rats. Cadmium exposure increased oxidative damage in rat bones; this was markedly decreased by puerarin treatment, as demonstrated by changes in the activity of antioxidative enzymes. Cadmium-induced blockage of the expression of key bone regulatory proteins, autophagy-related markers, and signaling molecules was also alleviated by puerarin treatment. Additionally, cadmium reduced expression of the autophagic protein Rab7 and of late endosomal/lysosomal adaptor and MAPK and mTOR activator 1 (LAMTOR1); the decrease in these proteins was not restored by puerarin treatment. We speculate that puerarin relieves the inhibition of fusion of autophagosomes with lysosomes that is induced by cadmium; however, this specific effect of puerarin and downstream effects on bone regulatory mechanisms require further investigation. In conclusion, puerarin alleviates cadmium-induced oxidative damage in the bones of rats by attenuating autophagy, which is likely associated with the antioxidant activity of puerarin.


Assuntos
Cádmio , Isoflavonas , Animais , Autofagia , Cádmio/toxicidade , Isoflavonas/farmacologia , Estresse Oxidativo , Ratos
10.
BMC Genomics ; 22(1): 724, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620091

RESUMO

BACKGROUND: Many studies on long chain non-coding RNAs (lncRNAs) are published in recent years. But the roles of lncRNAs in aortic dissection (AD) are still unclear and should be further examined. The present work focused on determining the molecular mechanisms underlying lncRNAs regulation in aortic dissection on the basis of the lncRNA-miRNA-mRNA competing endogenous RNA (ceRNA) network. METHODS: This study collected the lncRNAs (GSE52093), mRNAs (GSE52093) and miRNAs (GSE92427) expression data within human tissue samples with aortic dissection group and normal group based on Gene Expression Omnibus (GEO) database. RESULTS: This study identified three differentially expressed lncRNAs (DELs), 19 differentially expressed miRNAs (DEmiRs) and 1046 differentially expressed mRNAs (DEGs) identified regarding aortic dissection. Furthermore, we constructed a lncRNA-miRNA-mRNA network through three lncRNAs (including two with up-regulation and one with down-regulation), five miRNAs (five with up-regulation), as well as 211 mRNAs (including 103 with up-regulation and 108 with down-regulation). Simultaneously, we conducted functional enrichment and pathway analyses on genes within the as-constructed ceRNA network. According to our PPI/ceRNA network and functional enrichment analysis results, four critical genes were found (E2F2, IGF1R, BDNF and PPP2R1B). In addition, E2F2 level was possibly modulated via lncRNA FAM87A-hsa-miR-31-5p/hsa-miR-7-5p or lncRNA C9orf106-hsa-miR-7-5p. The expression of IGF1R may be regulated by lncRNA FAM87A-hsa-miR-16-5p/hsa-miR-7-5p or lncRNA C9orf106-hsa-miR-7-5p. CONCLUSION: In conclusion, the ceRNA interaction axis we identified is a potentially critical target for treating AD. Our results shed more lights on the possible pathogenic mechanism in AD using a lncRNA-associated ceRNA network.


Assuntos
Dissecção Aórtica , MicroRNAs , RNA Longo não Codificante , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética
11.
J Immunol ; 203(5): 1189-1197, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31308092

RESUMO

Invariant NKT (iNKT) cells provide rapid innate T cell responses to glycolipid Ags from host cells and microbes. The numbers of CD1d-restricted iNKT cells are tightly controlled in mucosal tissues, but the mechanisms have been largely unclear. We found that vitamin A is a dominant factor that controls the population size of mucosal iNKT cells in mice. This negative regulation is mediated by the induction of the purinergic receptor P2X7 on iNKT cells. The expression of P2X7 is particularly high on intestinal iNKT cells, making iNKT cells highly susceptible to P2X7-mediated cell death. In vitamin A deficiency, iNKT cells fail to express P2X7 and are, therefore, resistant to P2X7-mediated cell death, leading to iNKT cell overpopulation. This phenomenon is most prominent in the intestine. We found that iNKT cells are divided into CD69+ sphingosine-1-phosphate receptor 1 (S1P1)- tissue resident and CD69- S1P1+ nonresident iNKT cells. The CD69+ S1P1- tissue-resident iNKT cells highly express P2X7 and are effectively controlled by the P2X7 pathway. The regulation of iNKT cells by vitamin A by the P2X7 pathway is important to prevent aberrant expansion of effector cytokine-producing iNKT cells. Our findings identify a novel role of vitamin A in regulating iNKT cell homeostasis in many tissues throughout the body.


Assuntos
Células T Matadoras Naturais/imunologia , Receptores Purinérgicos P2X7/fisiologia , Vitamina A/fisiologia , Animais , Morte Celular , Citocinas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Deficiência de Vitamina A/imunologia
12.
Biom J ; 63(8): 1607-1622, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34319616

RESUMO

The Cox regression model is a commonly used model in survival analysis. In public health studies, clinical data are often collected from medical service providers of different locations. There are large geographical variations in the covariate effects on survival rates from particular diseases. In this paper, we focus on the variable selection issue for the Cox regression model with spatially varying coefficients. We propose a Bayesian hierarchical model which incorporates a horseshoe prior for sparsity and a point mass mixture prior to determine whether a regression coefficient is spatially varying. An efficient two-stage computational method is used for posterior inference and variable selection. It essentially applies the existing method for maximizing the partial likelihood for the Cox model by site independently first and then applying an Markov chain Monte Carlo algorithm for variable selection based on results of the first stage. Extensive simulation studies are carried out to examine the empirical performance of the proposed method. Finally, we apply the proposed methodology to analyzing a real dataset on respiratory cancer in Louisiana from the Surveillance, Epidemiology, and End Results (SEER) program.


Assuntos
Neoplasias , Teorema de Bayes , Humanos , Cadeias de Markov , Método de Monte Carlo , Modelos de Riscos Proporcionais , Análise de Sobrevida
13.
Fish Shellfish Immunol ; 101: 88-98, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32229294

RESUMO

Tumor necrosis factor receptor (TNFR)-associated factors (TRAFs) are a family of crucial signaling molecules that mediate the signal transduction of various immune signaling pathways. Extensive studies have demonstrated that TRAFs play vital roles in regulating cellular immune responses. However, the biological functions and expression profiling of TRAFs in Chinese soft-shelled turtle (Pelodiscus sinensis) remain unclear. In this study, the genes of the PsTRAF family at the genome-wide level were identified in P. sinensis, revealing six PsTRAF members that contained the conserved TRAF domain in the C-terminal regions. Molecular evolutionary analysis showed that PsTRAFs shared close evolutionary relationships and similar protein crystal structures with the TRAF homologs from other turtles, indicating the evolutionary conservation of PsTRAFs. Further expression analysis revealed the tissue-specific expression of PsTRAF genes. Obvious variations in the expression of PsTRAF genes were observed in the spleen in response to Aeromonas hydrophila infection. Three PsTRAF genes, PsTRAF2, PsTRAF3, and PsTRAF6, were significantly upregulated at the mRNA and protein levels post-infection, indicating their potential function in the immune response. Moreover, the protein-protein associations of PsTRAFs with several signaling receptors were predicted in P. sinensis. These results provide a basis for the investigation of the functional roles of PsTRAFs in immune defense against bacterial infection.


Assuntos
Genoma , Infecções por Bactérias Gram-Negativas/veterinária , Imunidade Inata/genética , Proteínas de Répteis/genética , Transcriptoma/imunologia , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/genética , Tartarugas , Aeromonas hydrophila/fisiologia , Animais , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Proteínas de Répteis/metabolismo , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo
14.
Environ Sci Technol ; 53(16): 9845-9854, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31348644

RESUMO

Identifying the key chemical compounds and source contributions in ambient particles associated with the burden of cardiopulmonary disease is important to develop cost-effective air pollution mitigating strategies that maximize the protection of public health. To help address this need, we examined 109 daily ambient fine particulate matter samples (PM2.5) that were collected in Beijing in one year. The samples were analyzed for chemical composition including organic and elemental carbons, metals, ions, as well as organic molecular markers. In addition, the secretion of pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were measured by exposing lung epithelial cells (A549) to water extracts of PM2.5 samples. Single pollutant and constituent-PM2.5 joint linear models were used to estimate the associations. Higher PM2.5 mass and measured chemical components were found in cold seasons than in warm seasons due to the greater contributions of secondary inorganic sources, biomass burning, and coal combustion. Water-soluble organic nitrogen (WSON) had the strongest associations with levels of pro-inflammatory cytokines compared to PM2.5 mass and other chemical species in both the one and constituent-PM2.5 joint linear models. Our study is the first to highlight that ambient WSON from diverse sources dominates the inflammatory potential of lung epithelial cells.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Pequim , Monitoramento Ambiental , Células Epiteliais , Nitrogênio , Material Particulado , Estações do Ano , Água
15.
Infect Immun ; 86(8)2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29784863

RESUMO

In animal models of experimental cerebral malaria (ECM), the glycosylphosphatidylinositols (GPIs) and GPI anchors are the major factors that induce nuclear factor kappa B (NF-κB) activation and proinflammatory responses, which contribute to malaria pathogenesis. GPIs and GPI anchors are transported to the cell surface via a process called GPI transamidation, which involves the GPI transamidase (GPI-T) complex. In this study, we showed that GPI16, one of the GPI-T subunits, is highly conserved among Plasmodium species. Genetic knockout of pbgpi16 (Δpbgpi16) in the rodent malaria parasite Plasmodium berghei strain ANKA led to a significant reduction of the amounts of GPIs in the membranes of merozoites, as well as surface display of several GPI-anchored merozoite surface proteins. Compared with the wild-type parasites, Δpbgpi16 parasites in C57BL/6 mice caused much less NF-κB activation and elicited a substantially attenuated T helper type 1 response. As a result, Δpbgpi16 mutant-infected mice displayed much less severe brain pathology, and considerably fewer Δpbgpi16 mutant-infected mice died from ECM. This study corroborated the GPI toxin as a significant inducer of ECM and further suggested that vaccines against parasite GPIs may be a promising strategy to limit the severity of malaria.


Assuntos
Aminoaciltransferases/metabolismo , Glicosilfosfatidilinositóis/metabolismo , Malária Cerebral/patologia , Malária Cerebral/parasitologia , Plasmodium berghei/enzimologia , Proteínas de Protozoários/metabolismo , Fatores de Virulência/metabolismo , Aminoaciltransferases/genética , Animais , Encéfalo/patologia , Membrana Celular/química , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Proteínas de Membrana/análise , Merozoítos/química , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Plasmodium berghei/genética , Proteínas de Protozoários/análise , Análise de Sobrevida , Células Th1/imunologia , Fatores de Virulência/genética
16.
Infect Immun ; 86(9)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29941462

RESUMO

High mobility group protein 1 (HMGB1) is considered to be the primary inflammatory factor triggering immune paralysis in late-phase sepsis. In this study, however, we wanted to explore the possibility of using HMGB1 to boost local differentiation of bone marrow cells (BMCs) into regulatory dendritic cells (DCs) in vivo, thereby inducing immune reversal in late-phase sepsis and improving the prognosis. For this purpose, sepsis was induced by cecal ligation and puncture (CLP). Mice were injected intraperitoneally with HMGB1 (10, 50, or 250 µg/kg of body weight) 7 days before CLP. BMCs and liver immune cells were isolated at 0, 3, 5, and 7 days post-CLP. Mice were intranasally infected with Pseudomonas aeruginosa 3 days post-CLP as a secondary pneumonia infection model. BMCs and liver cells isolated from septic mice pretreated with HMGB1 were adoptively transferred into CLP mice. GFP+-C57BL/6 and C3H/HeN-C3H/HeJ parabiosis models were established. We found that HMGB1 pretreatment improved the survival of sepsis and increased the numbers of BMCs and liver immune cells in CLP mice. Furthermore, HMGB1 stimulation improved survival in the secondary pneumonia infection model. HMGB1 increased the number as well as the percentage of CD11c- CD45RBhigh DCs in septic BM and liver. Adoptive transfer of septic cells pretreated with HMGB1 into CLP mice attenuated sepsis. HMGB1 enhanced the redistribution of CD11c- CD45RBhigh DCs through TLR4 signaling in parabiosis models. We conclude that HMGB1 triggers immune reversal through the mobilization, redistribution, and local immune differentiation of BMCs, thereby compensating for impaired immunity and leading to sufficient bacterial eradication.


Assuntos
Proteína HMGB1/imunologia , Proteína HMGB1/farmacologia , Pneumonia/imunologia , Sepse/tratamento farmacológico , Sepse/imunologia , Transferência Adotiva , Animais , Células da Medula Óssea/imunologia , Ceco , Diferenciação Celular , Células Dendríticas/imunologia , Modelos Animais de Doenças , Ligadura , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Parabiose , Pneumonia/microbiologia , Infecções por Pseudomonas/sangue , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/imunologia , Sepse/microbiologia , Receptor 4 Toll-Like/imunologia
17.
J Cell Sci ; 129(22): 4278-4288, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27802168

RESUMO

The microtubule cytoskeleton regulates cell polarity by spatially organizing membrane trafficking and signaling processes. In epithelial cells, microtubules form parallel arrays aligned along the apico-basal axis, and recent work has demonstrated that the members of CAMSAP/Patronin family control apical tethering of microtubule minus ends. Here, we show that in mammalian intestinal epithelial cells, the spectraplakin ACF7 (also known as MACF1) specifically binds to CAMSAP3 and is required for the apical localization of CAMSAP3-decorated microtubule minus ends. Loss of ACF7 but not of CAMSAP3 or its homolog CAMSAP2 affected the formation of polarized epithelial cysts in three-dimensional cultures. In short-term epithelial polarization assays, knockout of CAMSAP3, but not of CAMSAP2, caused microtubule re-organization into a more radial centrosomal array, redistribution of Rab11-positive (also known as Rab11A) endosomes from the apical cell surface to the pericentrosomal region and inhibition of actin brush border formation at the apical side of the cell. We conclude that ACF7 is an important regulator of apico-basal polarity in mammalian intestinal cells and that a radial centrosome-centered microtubule organization can act as an inhibitor of epithelial polarity.


Assuntos
Polaridade Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Células CACO-2 , Técnicas de Introdução de Genes , Técnicas de Silenciamento de Genes , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Microvilosidades/metabolismo , Ligação Proteica
18.
Malar J ; 17(1): 247, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973194

RESUMO

BACKGROUND: Border malaria, a shared phenomenon in the Greater Mekong Sub-region of Southeast Asia, is a major obstacle for regional malaria elimination. Along the China-Myanmar border, an additional problem arose as a result of the settlement of internally displaced people (IDP) in the border region. Since asymptomatic malaria significantly impacts transmission dynamics, assessment of the prevalence, dynamics and risk factors of asymptomatic malaria infections is necessary. METHODS: Cross-sectional surveys were carried out in 3 seasons (March and April, July and November) and 2 sites (villages and IDP camps) in 2015. A total of 1680 finger-prick blood samples were collected and used for parasite detection by microscopy and nested RT-PCR (nRT-PCR). Logistic regression models were used to explore the risk factors associated with asymptomatic malaria at individual and household levels. RESULTS: The prevalence of asymptomatic Plasmodium infections was 23.3% by nRT-PCR, significantly higher than that detected by microscopy (1.5%). The proportions of Plasmodium vivax, Plasmodium falciparum and mixed-species infections were 89.6, 8.1 and 2.3%, respectively. Asymptomatic infections showed obvious seasonality with higher prevalence in the rainy season. Logistic regression analysis identified males and school children (≤ 15 years) as the high-risk populations. Vector-based interventions, including bed net and indoor residual spray, were found to have significant impacts on asymptomatic Plasmodium infections, with non-users of these measures carrying much higher risks of infection. In addition, individuals living in poorly constructed households or farther away from clinics were more prone to asymptomatic infections. CONCLUSIONS: Sub-microscopic Plasmodium infections were highly prevalent in the border human populations from IDP camps and surrounding villages. Both individual- and household-level risk factors were identified, which provides useful information for identifying the high-priority populations to implement targeted malaria control.


Assuntos
Infecções Assintomáticas/epidemiologia , Coinfecção/epidemiologia , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Adolescente , Adulto , China/epidemiologia , Coinfecção/parasitologia , Estudos Transversais , Feminino , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Masculino , Mianmar/epidemiologia , Prevalência , Fatores de Risco , Estações do Ano , Adulto Jovem
20.
J Biol Chem ; 291(39): 20617-29, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27528609

RESUMO

During cytokinesis, the antiparallel array of microtubules forming the central spindle organizes the midbody, a structure that anchors the ingressed cleavage furrow and guides the assembly of abscission machinery. Here, we identified a role for the flavoprotein monooxygenase MICAL3, an actin disassembly factor, in organizing midbody-associated protein complexes. By combining cell biological assays with cross-linking mass spectrometry, we show that MICAL3 is recruited to the central spindle and the midbody through a direct interaction with the centralspindlin component MKLP1. Knock-out of MICAL3 leads to an increased frequency of cytokinetic failure and a delayed abscission. In a mechanism independent of its enzymatic activity, MICAL3 targets the adaptor protein ELKS and Rab8A-positive vesicles to the midbody, and the depletion of ELKS and Rab8A also leads to cytokinesis defects. We propose that MICAL3 acts as a midbody-associated scaffold for vesicle targeting, which promotes maturation of the intercellular bridge and abscission.


Assuntos
Citocinese/fisiologia , Oxigenases de Função Mista/metabolismo , Fuso Acromático/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Oxigenases de Função Mista/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fuso Acromático/genética , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
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