Involvement of JAK2 and MAPK on type II nitric oxide synthase expression in skin-derived dendritic cells

In this report, we demonstrate that a fetal mouse skin-derived dendritic cell line produces nitric oxide (NO) in response to the endotoxin [lipopolysaccharide (LPS)] and to cytokines [tumor necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF)]. Expression of the inducible isoform of NO synthase (iNOS) was confirmed by immunofluorescence with an antibody against iNOS. The tyrosine kinase inhibitor genistein decreased LPS- and GM-CSF-induced nitrite (NO(-2)) production. The effect of LPS and cytokines on NO(-2) production was inhibited by the Janus kinase 2 (JAK2) inhibitor tyrphostin B42. The p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB-203580 also reduced the NO(-2) production evoked by LPS, TNF-alpha, or GM-CSF, but it was not as effective as tyrphostin B42. Inhibition of MAPK kinase with PD-098059 also slightly reduced the effect of TNF-alpha or GM-CSF on NO(-2) production. Immunocytochemistry studies revealed that the transcription factor nuclear factor-kappaB was translocated from the cytoplasm into the nuclei of fetal skin-derived dendritic cells (FSDC) stimulated with LPS, and this translocation was inhibited by tyrphostin B42. Our results show that JAK2 plays a major role in the induction of iNOS in FSDC

Variations in Inflammatory Markers in Acute Myocardial Infarction: a Longitudinal Study

Actualmente a inflamação é considerada uma componente importante na aterosclerose, desde o seu início até à ruptura da placa seguida de trombose e da progressiva obstrução do vaso. A ruptura da cápsula fibrótica da placa expõe factores de tecido presentes no seu núcleo necrótico que induzem o processo inflamatório, promovendo a adesão celular e a coagulação e que conduzem à formação do trombo. Por seu turno, várias citocinas e moléculas de adesão celular contribuem activamente para o desenvolvimento da placa. Em particular a citocina TNF-a e a molécula de adesão intercelular (ICAM-1) poderão ser indicadoras de inflamação enquanto que as formas solúveis de P-selectina e de CD40 ligando (sCD40L) poderão dar a magnitude da activação plaquetária. Neste trabalho foram estudados 17 doentes com enfarte de miocárdio submetidos a angioplastia (grupo AMI) e 16 doentes com confirmação angiográfica de ausência de doença coronária. Os doentes do grupo AMI foram seguidos nas primeiras 24h de evolução do enfarte agudo de miocárdio antes da administração de medicação e da intervenção angiográfica e ao longo do período de recuperação, 2 e 40 dias após enfarte. Foram medidas no soro por imunoensaio as concentrações de TNF-a e das formas solúveis de CD40L, ICAM-1 e P-selectina. Foram observadas variações significativas de sP-selectina relativamente aos controlos. Imediatamente após o enfarte de miocárdio verificou-se um aumento de sP-selectina, seguido de uma descida brusca dos seus níveis às 48h, e de um incremento para valores idênticos aos observados no grupo de controlo ao 40º dia. As variações observadas nas concentrações de sCD40L não foram significativas relativamente aos controlos. No entanto, verificou-se uma tendência de diminuição da concentração até 48h após o enfarte de miocárdio, seguindo-se um aumento que atingiu valores ligeiramente superiores ao do grupo controlo no 40º dia. As concentrações de TNF-a medidas foram sistematicamente superiores às verificadas no grupo controlo, tendo-se ainda observado uma subida gradual desde o enfarte de miocárdio até ao 40º dia, sendo este incremento significativo. Os valores de sICAM-1 não apresentaram quaisquer variações após o enfarte nem relativamente ao grupo controlo. As variações observadas sugerem um papel importante destes marcadores no processo inflamatório e na evolução do enfarte de miocárdio. O aumento brusco da concentração de sP-selectina após o enfarte de miocárdio evidencia a activação plaquetária e trombose. Na evolução do enfarte, e à medida que as variáveis hemodinâmicas retornam a valores estáveis, devido à medicação aplicada, o aumento de sCD40L e TNF-a em circulação pode reflectir o papel destas moléculas na recuperação endotelial e do miocárdio

Differential activation of nuclear factor kappa B subunits in a skin dendritic cell line in response to the strong sensitizer 2,4-dinitrofluorobenzene

Dendritic cell (DC) maturation is essential for the initiation of T-dependent immune responses. Nuclear factor kappa B (NF-kappaB) transcription factors are ubiquitously expressed signalling molecules, known to regulate the transcription of a large number of genes involved in immune responses, including cytokines and cell surface molecules. In this work, we studied the time-dependent activation of five members of the NF-kappaB family, p50, p52, p65, RelB and cRel, in a mouse skin DC line in response to stimulation with the strong sensitizer, 2,4-dinitrofluorobenzene (DNFB). Western blot assay revealed that exposure of fetal skin DC (FSDC) to DNFB induced the degradation of the inhibitor of NF-kappaB (IkappaB). Three out of its five members, i.e. p50, p52, and RelB, were similarly activated upon DNFB stimulation, with subsequent translocation of these subunits from the cytosol to the nucleus, but with different kinetics. In contrast, p65 expression was diminished in both the nucleus and the cytosol. The electrophoretic mobility shift assay (EMSA) showed that exposure of FSDC to DNFB induced DNA binding to NF-kappaB. Together, these results show that DNFB differentially activates the various members of the NF-kappaB family in skin DC

Granulocyte-macrophage colony-stimulating factor activates the transcription of nuclear factor kappa B and induces the expression of nitric oxide synthase in a skin dendritic cell line.

Nitric oxide (NO) produced by skin dendritic cells and keratinocytes plays an important role in skin physiology, growth and remodelling. Nitric oxide is also involved in skin inflammatory processes and in modulating antigen presentation (either enhancing or suppressing it). In this study, we found that GM-CSF stimulates the expression of the inducible isoform of nitric oxide synthase (iNOS) in a fetal-skin-derived dendritic cell line (FSDC) and, consequently, increases the nitrite production from 11.9 +/- 3.2 micromol/L (basal level) to 26.9 +/- 4.2 micromol/L. Pyrrolidinedithiocarbamate (PDTC) inhibits nitrite production, with a half maximal inhibitory concentration (IC50) of 19.3 micromol/L and the iNOS protein expression in FSDC. In addition, western blot assays revealed that exposure of FSDC to GM-CSF induces the phosphorylation and degradation of the inhibitor of NF-kappaB (IkB), with subsequent translocation of the p50, p52 and RelB subunits of the transcription nuclear factor kappa B (NF-kappaB) from the cytosol to the nucleus. Electrophoretic mobility shift assays (EMSA) showed that FSDC exposure to GM-CSF activates the transcription factor NF-kappaB. Together, these results show that GM-CSF induces iNOS expression in skin dendritic cells by a mechanism involving activation of the NF-kappaB pathway

Optimum quantum dot size for highly efficient fluorescence bioimaging

Semiconductor quantum dots of few nanometers have demonstrated a great potential for bioimaging. The size determines the emitted color, but it is also expected to play an important role in the image brightness. In this work, the size dependence of the fluorescence quantum yield of the highly thermal sensitive CdTe quantum dots has been systematically investigated by thermal lens spectroscopy. It has been found that an optimum quantum yield is reached for 3.8-nm quantum dots. The presence of this optimum size has been corroborated in both one-photon excited fluorescence experiments and two-photon fluorescence microscopy of dot-incubated cancer cells. Combination of quantum yield and fluorescence decay time measurements supports that the existence of this optimum size emerges from the interplay between the frequency-dependent radiative emission rate and the size-dependent coupling strength between bulk excitons and surface trapping states

The influence of semantic and phonological factors on syntactic decisions: An event-related brain potential study

During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors

Altered thymic differentiation and modulation of arthritis by invariant NKT cells expressing mutant ZAP70

Various subsets of invariant natural killer T (iNKT) cells with different cytokine productions develop in the mouse thymus, but the factors driving their differentiation remain unclear. Here we show that hypomorphic alleles of Zap70 or chemical inhibition of Zap70 catalysis leads to an increase of IFN-gamma-producing iNKT cells (NKT1 cells), suggesting that NKT1 cells may require a lower TCR signal threshold. Zap70 mutant mice develop IL-17-dependent arthritis. In a mouse experimental arthritis model, NKT17 cells are increased as the disease progresses, while NKT1 numbers negatively correlates with disease severity, with this protective effect of NKT1 linked to their IFN-gamma expression. NKT1 cells are also present in the synovial fluid of arthritis patients. Our data therefore suggest that TCR signal strength during thymic differentiation may influence not only IFN-gamma production, but also the protective function of iNKT cells in arthritis

Validação conceitual das características definidoras de diagnósticos de enfermagem respiratórios em neonatos

OBJECTIVE:To develop and validate conceptual and operational definitions for the defining characteristics of the respiratory nursing diagnoses, ineffective breathing pattern, impaired gas exchange and impaired spontaneous ventilation, in newborns.METHODS:This was a methodological study of conceptual validation of the defining characteristics of three respiratory nursing diagnoses, by consensus analysis of a committee of five specialist nurses, and then a group of five non-nursing professionals, using the Delphi technique.RESULTS:After two rounds of evaluation, consensus was obtained that was equal to or greater than 80% on all of the definitions, which were then considered validated.CONCLUSION:The definitions developed for the defining characteristics of three nursing diagnoses were validated with a high level of consensus.OBJETIVO:Elaborar e validar definições conceituais e operacionais para as características definidoras dos diagnósticos de enfermagem respiratórios, Padrão Respiratório Ineficaz, Troca de Gases Prejudicada e Ventilação Espontânea Prejudicada em recém-nascidos.MÉTODOS:Estudo metodológico, de validação conceitual das características definidoras dos três diagnósticos de enfermagem respiratórios por meio da análise de consenso de um comitê de cinco enfermeiras especialistas e de cinco profissionais não enfermeiros, utilizando a técnica Delphi.RESULTADOS:Após duas rodadas de avaliação, obteve-se consenso igual ou superior a 80% na totalidade das definições, sendo consideradas validadas.CONCLUSÃO:As definições elaboradas para as características definidoras dos três diagnósticos de enfermagem foram validadas com elevado grau de consenso.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de EnfermagemUNIFESP, EPESciEL