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1.
bioRxiv ; 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37215000

RESUMO

Group A Streptococcus (GAS) infections can cause neuropsychiatric sequelae in children due to post-infectious encephalitis. Multiple GAS infections induce migration of Th17 lymphocytes from the nose into the brain, which are critical for microglial activation, blood-brain barrier (BBB) and neural circuit impairment in a mouse disease model. How endothelial cells (ECs) and microglia respond to GAS infections, and which Th17-derived cytokines are essential for these responses are unknown. Using single-cell RNA sequencing and spatial transcriptomics, we found that ECs downregulate BBB genes and microglia upregulate interferon-response, chemokine and antigen-presentation genes after GAS infections. Several microglial-derived chemokines were elevated in patient sera. Administration of a neutralizing antibody against interleukin-17A (IL-17A), but not ablation of granulocyte-macrophage colony-stimulating factor (GM-CSF) in T cells, partially rescued BBB dysfunction and microglial expression of chemokine genes. Thus, IL-17A is critical for neuropsychiatric sequelae of GAS infections and may be targeted to treat these disorders.

2.
Vis J Emerg Med ; 30: 101603, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36718415
3.
Int J Mol Sci ; 22(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34830054

RESUMO

Chimeric RNAs are often associated with chromosomal rearrangements in cancer. In addition, they are also widely detected in normal tissues, contributing to transcriptomic complexity. Despite their prevalence, little is known about the characteristics and functions of chimeric RNAs. Here, we examine the genetic structure and biological roles of CLEC12A-MIR223HG, a novel chimeric transcript produced by the fusion of the cell surface receptor CLEC12A and the miRNA-223 host gene (MIR223HG), first identified in chronic myeloid leukemia (CML) patients. Surprisingly, we observed that CLEC12A-MIR223HG is not just expressed in CML, but also in a variety of normal tissues and cell lines. CLEC12A-MIR223HG expression is elevated in pro-monocytic cells resistant to chemotherapy and during monocyte-to-macrophage differentiation. We observed that CLEC12A-MIR223HG is a product of trans-splicing rather than a chromosomal rearrangement and that transcriptional activation of CLEC12A with the CRISPR/Cas9 Synergistic Activation Mediator (SAM) system increases CLEC12A-MIR223HG expression. CLEC12A-MIR223HG translates into a chimeric protein, which largely resembles CLEC12A but harbours an altered C-type lectin domain altering key disulphide bonds. These alterations result in differences in post-translational modifications, cellular localization, and protein-protein interactions. Taken together, our observations support a possible involvement of CLEC12A-MIR223HG in the regulation of CLEC12A function. Our workflow also serves as a template to study other uncharacterized chimeric RNAs.


Assuntos
Fusão Gênica , Lectinas Tipo C/genética , Leucemia Mieloide/genética , MicroRNAs/genética , Proteínas Mutantes Quiméricas/genética , Receptores Mitogênicos/genética , Trans-Splicing , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Citarabina/farmacologia , Humanos , Lectinas Tipo C/metabolismo , Leucemia Mieloide/metabolismo , MicroRNAs/metabolismo , Proteínas Mutantes Quiméricas/metabolismo , Receptores Mitogênicos/metabolismo , Ativação Transcricional
5.
Arch Clin Neuropsychol ; 35(4): 385-400, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31696205

RESUMO

OBJECTIVE: Internet use and mobile devices permeate every aspect of our lives and are changing our financial habits. Assessment of financial decision-making (FDM) has not yet caught up to apparent changes in financial behavior. To modernize assessment methods and create current and comprehensive FDM frameworks, we first need to establish the most commonly used and most preferred methods of performing specific financial activities. METHOD: Cross-sectional survey data were collected using an online platform and offline approaches (in person and by mail) (N = 234). The frequency of using technological (e.g., laptop) and non-technological (e.g., in-person banking) means of completing seven financial activities was assessed first, including Depositing checks, Reviewing bank statements, Keeping track of money spent, Transferring funds, Withdrawing cash, Paying bills, and Purchasing products online. Second, preference for technological versus non-technological methods was assessed. Finally, linear regression models examined associations between demographics and preference for technological methods for each financial activity. RESULTS: The majority of respondents (77% online, 74% offline) used technology to perform various financial activities and preferred technological to non-technological methods for completing five out of the six financial activities. Increased preference for technological methods was associated with younger age for all the financial activities, and higher education was associated with reviewing bank statement and transferring funds. CONCLUSIONS: Our survey findings provide empirical evidence for the changing nature of our financial habits. We discuss the implications of this change for researchers, clinicians, and the individuals themselves and emphasize the importance of modernizing FDM tools.


Assuntos
Internet , Aplicativos Móveis , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Inquéritos e Questionários , Tecnologia
6.
Chem Sci ; 9(22): 5039-5046, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29938033

RESUMO

The photocatalyzed insertion of dioxygen into the Pt(ii)-methyl bond in terpyridine platinum complexes has been shown to proceed efficiently, but its mechanism remains a challenge. In particular, there are serious counter-intuitive differences in the reactivity of structurally similar complexes. M06 calculations in solvent with a valence double-ζ basis set supplemented by polarization and diffusion shells (benchmarked against ωB97x-D calculations with a larger basis set) are able to provide a satisfactory mechanistic answer. The proposed mechanism starts with the absorption of a photon by the metal complex, which then evolves into a triplet state that reacts with the triplet dioxygen fragment. A variety of possible reaction paths have been identified, some leading to the methylperoxo product and others reverting to the reactants, and the validity of some of these paths has been confirmed by additional experiments. The balance between the barriers towards productive and unproductive paths reproduces the diverging experimental behavior of similar complexes and provides a general mechanistic picture for these processes.

7.
Nat Commun ; 8: 14882, 2017 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-28358028

RESUMO

Self-assembly offers a general strategy for the preparation of large, hollow high-symmetry structures. Although biological capsules, such as virus capsids, are capable of selectively recognizing complex cargoes, synthetic encapsulants have lacked the capability to specifically bind large and complex biomolecules. Here we describe a cubic host obtained from the self-assembly of FeII and a zinc-porphyrin-containing ligand. This cubic cage is flexible and compatible with aqueous media. Its selectivity of encapsulation is driven by the coordination of guest functional groups to the zinc porphyrins. This new host thus specifically encapsulates guests incorporating imidazole and thiazole moieties, including drugs and peptides. Once encapsulated, the reactivity of a peptide is dramatically altered: encapsulated peptides are protected from trypsin hydrolysis, whereas physicochemically similar peptides that do not bind are cleaved.

8.
J Strength Cond Res ; 27(1): 137-45, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23254488

RESUMO

The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.


Assuntos
Desempenho Atlético/fisiologia , Navios , Esportes/fisiologia , Limiar Anaeróbio/fisiologia , Comportamento Competitivo , Metabolismo Energético , Teste de Esforço , Fadiga/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Japão , Masculino , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Análise de Regressão , Adulto Jovem
9.
J Leukoc Biol ; 90(4): 653-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21504949

RESUMO

The thymus harbors HIV-1 and supports its replication. Treatment with PI-containing ART restores thymic output of naïve T cells. This study demonstrates that CXCR4-using WT viruses are more sensitive to PI in fetal thymcocytes than mature T cells with average IC(50) values for two PIs, RTV and IDV, of 1.5 nM (RTV) and 4.4 nM (IDV) in thymocytes versus 309.4 nM (RTV) and 27.3 nM (IDV) in mature T cells. P-gp activity, as measured using Rh123 efflux and quantitation of P-gp mRNA, increased with thymocyte maturation into CD4 and CD8 lineage T cells. P-gp activity is developmentally regulated in the thymus. Thymocytes developed increased levels of P-gp activity as maturation from DP to SP CD4 or CD8 T cells occurred, although CD4 T cells acquired activity more rapidly. Reduced P-gp activity in thymocytes is one mechanism for effectiveness of PI therapy in suppressing viral replication in the thymus and in reconstitution of naïve T cells, particularly among children receiving PI-containing ART.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Inibidores da Protease de HIV/farmacologia , RNA Mensageiro/metabolismo , Timo/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Inibidores da Protease de HIV/farmacocinética , HIV-1/fisiologia , Humanos , Lactente , Recém-Nascido , Masculino , Timo/citologia , Replicação Viral/efeitos dos fármacos , Replicação Viral/fisiologia
10.
AIDS ; 23(13): 1631-40, 2009 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-19625947

RESUMO

OBJECTIVE: To identify novel viral determinants in HIV-1 protease, Gag, and envelope V3 that relate to outcomes to initial protease inhibitor-based antiretroviral therapy. DESIGN: A longitudinal cohort study of protease inhibitor-naive, HIV-infected individuals was designed to identify genetic variables in viral Gag and envelope sequences associated with response to antiretroviral therapy. METHODS: Genetic and statistical models, including amino acid profiles, phylogenetic analyses, receiver operating characteristic analyses, and covariation analyses, were used to evaluate viral sequences and clinical variables from individuals who developed immune reconstitution with or without suppression of viral replication. RESULTS: Pretherapy chemokine (C-X-C motif) receptor 4-using V3 regions had significant associations with viral failure (P = 0.04). Amino acid residues in protease covaried with Gag residues, particularly in p7(NC), independent of cleavage sites. Pretherapy V3 charge combined with p6(Pol) and p2/p7(NC) cleavage site genotypes produced the best three-variable model to predict viral suppression in 88% of individuals. Combinations of baseline CD4 cell percentage with genetic determinants in Gag-protease predicted viral fitness in 100% of individuals who failed to suppress viral replication. CONCLUSION: Baseline genetic determinants in Gag p6(Pol) and p2/p7(NC), as well as envelope, provide novel combinations of biomarkers for predicting emergence of viral resistance to initial therapy regimens.


Assuntos
Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , Fragmentos de Peptídeos/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Adolescente , Terapia Antirretroviral de Alta Atividade/métodos , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Farmacorresistência Viral Múltipla/genética , Marcadores Genéticos , Variação Genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Humanos , Lactente , Estudos Longitudinais , Filogenia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral
11.
J Sports Sci ; 27(1): 37-47, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19031333

RESUMO

In this study, video and force analysis techniques were used to distinguish between dragon boat paddlers of different ability. Six elite paddlers (three males, three females) and six sub-elite paddlers (two males, four females) were compared during high-intensity paddling (80-90 strokes.min(-1)). Video filming was conducted for two-dimensional kinematic analysis and an instrumented paddle was used to collect force data. Paddling efficiency, paddle force characteristics, and paddler kinematic variables were measured. Elite paddlers achieved higher paddling efficiency than sub-elite paddlers (elite: 76+/-4%; sub-elite: 67+/-10%; P=0.080). Elite paddlers also showed higher peak force (elite: 16.3+/-4.8 N.kg(-2/3); sub-elite: 11.4+/-2.6 N.kg(-2/3); P=0.052), average force (elite: 7.9+/-2.8 N.kg(-2/3); sub-elite: 5.5+/-1.4 N.kg(-2/3); P=0.084), and impulse (elite: 3.0+/-0.9 (N.s).kg(-2/3); sub-elite: 1.9+/-0.4 (N.s).kg(-2/3); P=0.026) than sub-elite paddlers, but these three results should be viewed with caution due to the small sample size and the unequal number of males and females in the two groups. Superior technique and greater strength enable the elite paddlers to achieve higher paddling efficiency. Paddlers use different joint movement patterns to develop propulsion, which are reflected in variations in the force-time curve.


Assuntos
Desempenho Atlético , Fenômenos Biomecânicos , Metabolismo Energético , Navios , Esportes/fisiologia , Adulto , Peso Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Virology ; 378(2): 272-81, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18599104

RESUMO

Regions of HIV-1 gag between p2 and p6(Gag)/p6(Pol), in addition to protease (PR), develop genetic diversity in HIV-1 infected individuals who fail to suppress virus replication by combination protease inhibitor (PI) therapy. To elucidate functional consequences for viral replication and PI susceptibility by changes in Gag that evolve in vivo during PI therapy, a panel of recombinant viruses was constructed. Residues in Gag p2/p7(NC) cleavage site and p7(NC), combined with residues in the flap of PR, defined novel fitness determinants that restored replicative capacity to the posttherapy virus. Multiple determinants in Gag have a dominant effect on PR phenotype and increase susceptibility to inhibitors of drug-resistant or drug-sensitive PR genes. Gag determinants of drug sensitivity and replication alter the fitness landscape of the virus, and viral replicative capacity can be independent of drug sensitivity. The functional linkage between Gag and PR provides targets for novel therapeutics to inhibit drug-resistant viruses.


Assuntos
Substituição de Aminoácidos/genética , Farmacorresistência Viral , Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Replicação Viral/efeitos dos fármacos , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Sequência de Aminoácidos , Linhagem Celular , Protease de HIV/genética , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , Humanos , Dados de Sequência Molecular , Recombinação Genética
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