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1.
Pediatr Rev ; 44(10): 598-600, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37777649
2.
Dev Sci ; 23(2): e12881, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31206995

RESUMO

Bilingual infants from 6- to 24-months of age are more likely to generalize, flexibly reproducing actions on novel objects significantly more often than age-matched monolingual infants are. In the current study, we examine whether the addition of novel verbal labels enhances memory generalization in a perceptually complex imitation task. We hypothesized that labels would provide an additional retrieval cue and aid memory generalization for bilingual infants. Specifically, we hypothesized that bilinguals might be more likely than monolinguals to map multiple perceptual features onto a novel label and therefore show enhanced generalization. Eighty-seven 18-month-old monolingual and bilingual infants were randomly assigned to one of two experimental conditions or a baseline control condition. In the experimental conditions, either no label or a novel label was added during demonstration and again at the beginning of the test session. After a 24-hr delay, infants were tested with the same stimulus set to test cued recall and with a perceptually different but functionally equivalent stimulus set to test memory generalization. Bilinguals performed significantly above baseline on both cued recall and memory generalization in both experimental conditions, whereas monolinguals performed significantly above baseline only on cued recall in both experimental conditions. These findings show a difference between monolinguals and bilinguals in memory generalization and suggest that generalization differences between groups may arise from visual perceptual processing rather than linguistic processing. A video abstract of this article can be viewed at https://youtu.be/yXB4pM3fF2k.


Assuntos
Memória , Multilinguismo , Sinais (Psicologia) , Feminino , Generalização Psicológica , Humanos , Lactente , Masculino , Rememoração Mental , Percepção Visual
3.
J Asthma ; 55(8): 898-906, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28933971

RESUMO

OBJECTIVE: Characterize fluticasone propionate (Fp) and combination fluticasone propionate and salmeterol (FS) pharmacokinetic and safety profiles, delivered via a novel, inhalation-driven, multidose dry powder inhaler (MDPI). METHODS: This multicenter, open-label, four-period crossover, single-dose study randomized patients aged ≥12 years with persistent asthma to Fp MDPI 200 mcg, FS MDPI 200/12.5 mcg, Fp dry powder inhaler (DPI) 500 mcg (250 mcg × 2 inhalations), or FS DPI 500/50 mcg. Blood samples for determination of Fp and salmeterol pharmacokinetic parameters including Cmax, AUC0-t, AUC0-inf, tmax, and t½ were collected predose through 36 h postdose (14 time points). Safety assessments comprised adverse events, vital signs, and physical examinations. The institutional review board approved the study protocol. RESULTS: The pharmacokinetic analysis set and safety population each included 40 patients. Fp systemic exposure (Cmax, AUC0-t, and AUC0-inf) was highest for Fp DPI 500 mcg and similar for Fp MDPI 200 mcg, FS MDPI 200/12.5 mcg, and FS DPI 500/50 mcg. Fp geometric mean t½ values were similar across treatments. Salmeterol Cmax was 20% lower and AUC0-t and AUC0-inf were approximately 50% lower with FS MDPI versus FS DPI. Median tmax and geometric mean t½ were similar between FS MDPI and FS DPI. Adverse events were similar across treatments with no relevant changes in vital signs, physical examinations, or hematology test results. CONCLUSIONS: Fp MDPI and FS MDPI produced similar or lower systemic exposure to Fp and salmeterol, despite lower doses, versus conventional DPI devices, suggesting improved efficiency due to formulation and device differences.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Combinação Fluticasona-Salmeterol/administração & dosagem , Fluticasona/administração & dosagem , Administração por Inalação , Adolescente , Adulto , Idoso , Área Sob a Curva , Asma/patologia , Broncodilatadores/efeitos adversos , Broncodilatadores/farmacocinética , Criança , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Resistência a Medicamentos , Inaladores de Pó Seco , Feminino , Fluticasona/efeitos adversos , Fluticasona/farmacocinética , Combinação Fluticasona-Salmeterol/efeitos adversos , Combinação Fluticasona-Salmeterol/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
4.
FEMS Microbiol Lett ; 364(14)2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28854673

RESUMO

The genome sequence of the obligate chemolithoautotroph Hydrogenovibrio crunogenus paradoxically predicts a complete oxidative citric acid cycle (CAC). This prediction was tested by multiple approaches including whole cell carbon assimilation to verify obligate autotrophy, phylogenetic analysis of CAC enzyme sequences and enzyme assays. Hydrogenovibrio crunogenus did not assimilate any of the organic compounds provided (acetate, succinate, glucose, yeast extract, tryptone). Enzyme activities confirmed that its CAC is mostly uncoupled from the NADH pool. 2-Oxoglutarate:ferredoxin oxidoreductase activity is absent, though pyruvate:ferredoxin oxidoreductase is present, indicating that sequence-based predictions of substrate for this oxidoreductase were incorrect, and that H. crunogenus may have an incomplete CAC. Though the H. crunogenus CAC genes encode uncommon enzymes, the taxonomic distribution of their top matches suggests that they were not horizontally acquired. Comparison of H. crunogenus CAC genes to those present in other 'Proteobacteria' reveals that H. crunogenus and other obligate autotrophs lack the functional redundancy for the steps of the CAC typical for facultative autotrophs and heterotrophs, providing another possible mechanism for obligate autotrophy.


Assuntos
Carbono/metabolismo , Ciclo do Ácido Cítrico , Fontes Hidrotermais/microbiologia , Piscirickettsiaceae/metabolismo , Crescimento Quimioautotrófico , Glucose/metabolismo , Oxirredução , Filogenia , Piscirickettsiaceae/classificação , Piscirickettsiaceae/genética , Ácido Pirúvico/metabolismo
5.
Clin Pharmacol ; 7: 87-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26491375

RESUMO

BACKGROUND: Pexmetinib (ARRY-614) is a dual inhibitor of p38 mitogen-activated protein kinase and Tie2 signaling pathways implicated in the pathogenesis of myelodysplastic syndromes. Previous clinical experience in a Phase I dose-escalation study of myelodysplastic syndrome patients using pexmetinib administered as neat powder-in-capsule (PIC) exhibited high variability in pharmacokinetics and excessive pill burden, prompting an effort to improve the formulation of pexmetinib. METHODS: A relative bioavailability assessment encompassed three parallel treatment cohorts of unique subjects comparing the two new formulations (12 subjects per cohort), a liquid oral suspension (LOS) and liquid-filled capsule (LFC) and the current clinical PIC formulation (six subjects) in a fasted state. The food-effect assessment was conducted as a crossover of the LOS and LFC formulations administered under fed and fasted conditions. Subjects were divided into two groups of equal size to evaluate potential period effects on the food-effect assessment. RESULTS: The geometric mean values of the total plasma exposures based upon area-under-the-curve to the last quantifiable sample (AUClast) of pexmetinib were approximately four- and twofold higher after administration of the LFC and LOS formulations, respectively, than after the PIC formulation, when the formulations were administered in the fasted state. When the LFC formulation was administered in the fed state, pexmetinib AUClast decreased by <5% compared with the fasted state. After administration of the LOS formulation in the fed state, pexmetinib AUClast was 34% greater than observed in the fasted state. CONCLUSION: These results suggest that the LFC formulation of pexmetinib may achieve greater exposures with lower doses due to the greater bioavailability compared to the PIC, and remain unaffected by coadministration with food.

6.
J Immunol ; 187(4): 1591-600, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21734072

RESUMO

Exosomes (EXO) are secreted intracellular microparticles that can trigger inflammation and induce Ag-specific immune responses. To test possible roles of EXO in autoimmunity, we isolated small microparticles, mainly EXO, from mouse insulinoma and examined their activities to stimulate the autoimmune responses in NOD mice, a model for human type 1 diabetes. We demonstrate that the EXO contains strong innate stimuli and expresses candidate diabetes autoantigens. They can induce secretion of inflammatory cytokines through a MyD88-dependent pathway, and activate purified APC and result in T cell proliferation. To address whether EXO or the secreted microparticles are possible autoimmune targets causing islet-specific inflammation, we monitored the T cell responses spontaneously developed in prediabetic NOD mice for their reactivity to the EXO, and compared this reactivity between diabetes-susceptible and -resistant congenic mouse strains. We found that older NOD females, which have advanced islet destruction, accumulated more EXO-reactive, IFN-γ-producing lymphocytes than younger females or age-matched males, and that pancreatic lymph nodes from the prediabetic NOD, but not from the resistant mice, were also enriched with EXO-reactive Th1 cells. In vivo, immunization with the EXO accelerates insulitis development in nonobese diabetes-resistant mice. Thus, EXO or small microparticles can be recognized by the diabetes-associated autoreactive T cells, supporting that EXO might be a possible autoimmune target and/or insulitis trigger in NOD or congenic mouse strains.


Assuntos
Micropartículas Derivadas de Células/imunologia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Insulinoma/imunologia , Ativação Linfocitária/imunologia , Células Th1/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/metabolismo , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Exossomos/imunologia , Exossomos/metabolismo , Feminino , Humanos , Células Secretoras de Insulina/metabolismo , Insulinoma/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fator 88 de Diferenciação Mieloide/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Caracteres Sexuais , Células Th1/metabolismo
7.
Toxicol Sci ; 89(2): 535-46, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16280383

RESUMO

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a member of the nuclear receptor superfamily whose ligands, the peroxisome proliferators (PPs), are liver tumor promoters in rodents. Interaction cloning was performed using bacterially expressed PPARalpha to identify proteins involved in PP signaling. The ribosomal protein L11 (rpL11), a component of the large 60S subunit, was identified as a PPARalpha-associated protein. Since rpL11 is a regulator of p53 and the cell cycle, the association between this protein and PPARalpha was examined in detail. PPARalpha-rpL11 interaction was confirmed using yeast and mammalian two-hybrid systems as well as in vitro pull-down assays. The association with rpL11 occurs within the D-domain (hinge-region) of PPARalpha. Unlike PPARalpha, the two closely related isoforms PPARbeta and gamma do not interact with rpL11. Cotransfection of mammalian cells with rpL11 resulted in ligand-dependent inhibition of transcriptional activity of PPARalpha. Ribosomal protein L11-mediated inhibition of gene expression is associated with decreased binding to the PPAR-response element (PPRE) DNA sequence. Release of rpL11 from the ribosome by serum deprivation or low-dose actinomycin D did not dramatically affect PPRE-driven luciferase activity when PPARalpha was overexpressed by cotransfection. However, when endogenous levels of PPARalpha are examined and rpL11 concentration is manipulated by expression by small interference RNA, the ability of peroxisome proliferator to induce PPRE-driven reporter activity and target gene mRNA is affected. These studies show that rpL11 inhibits PPARalpha activity and adds further evidence that ribosomal proteins play roles in the control of transcriptional regulation.


Assuntos
PPAR alfa/antagonistas & inibidores , Proteínas Ribossômicas/metabolismo , Transcrição Gênica , Animais , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Clonagem Molecular , Ligantes , PPAR alfa/genética , Proliferadores de Peroxissomos/farmacologia , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Ribossômicas/genética , Saccharomyces cerevisiae/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Técnicas do Sistema de Duplo-Híbrido
8.
Toxicol Appl Pharmacol ; 188(3): 185-98, 2003 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12729718

RESUMO

Peroxisome proliferators (PPs) are an important class of chemicals that act as hepatic tumor promoters in laboratory rodents. The key target for PPs is the nuclear receptor peroxisome proliferator-activated receptor-alpha (PPARalpha) and these chemicals cause cancer by altering the expression of a subset of genes involved in cell growth regulation. The purpose of the present study was to utilize high-density gene expression arrays to examine the genes regulated by the potent PP Wy14,643 (50 microM, 6 h) in both rat (FaO) and human (HepG2) hepatoma cells. Treatment of FaO cells, but not HepG2, revealed the expected fatty acid catabolism genes. However, a larger than expected number of protein kinases, phosphatases, and signaling molecules were also affected exclusively in the FaO cells, including MAPK-phosphatase 1 (MKP-1), Janus-activated kinases 1 and 2 (JAK1 and 2), and glycogen synthetase kinase alpha and beta (GSKalpha and beta). The mRNA accumulation of these genes as well as the protein level for GSK3alpha, JAK1, and JAK2 and MKP-1 activity was corroborated. Due to the importance of MKP-1 in cell signaling, this induction was examined further and was found to be controlled, at least in part, at the level of the gene's promoter. Interestingly, overexpression of MKP-1 in turn affected the constitutive activity of PPARalpha. Taken together, the gene expression arrays revealed an important subset of PP-regulated genes to be kinases and phosphatases. These enzymes not only would affect growth factor signaling and cell cycle control but also could represent feedback control mechanisms and modulate the activity of PPARalpha.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proliferadores de Peroxissomos/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Carcinoma Hepatocelular/enzimologia , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/genética , Genes Reporter/genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Monoéster Fosfórico Hidrolases/biossíntese , Proteínas Quinases/biossíntese , RNA Mensageiro/análise , Ratos , Receptores Citoplasmáticos e Nucleares/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Fatores de Transcrição/biossíntese , Células Tumorais Cultivadas
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