6,593 research outputs found
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
Endothelial Jagged1 promotes solid tumor growth through both pro-angiogenic and angiocrine functions
Angiogenesis is an essential process required for tumor growth and progression. The Notch signaling pathway has been identified as a key regulator of the neo-angiogenic process. Jagged-1 (Jag1) is a Notch ligand required for embryonic and retinal vascular development, which direct contribution to the regulation of tumor angiogenesis remains to be fully characterized.
The current study addresses the role of endothelial Jagged1-mediated Notch signaling in the context of tumoral angiogenesis in two different mouse tumor models: subcutaneous Lewis Lung Carcinoma (LLC) tumor transplants and the autochthonous Transgenic Adenocarcinoma of the Mouse Prostate (TRAMP).
The role of endothelial Jagged1 in tumor growth and neo-angiogenesis was investigated with endothelial-specific Jag1 gain- and loss-of-function mouse mutants (eJag1OE and eJag1cKO). By modulating levels of endothelial Jag1, we observed that this ligand regulates tumor vessel density, branching, and perivascular maturation, thus affecting tumor vascular perfusion. The pro-angiogenic function is exerted by its ability to positively regulate levels of Vegfr-2 while negatively regulating Vegfr-1. Additionally, endothelial Jagged1 appears to exert an angiocrine function possibly by activating Notch3/Hey1 in tumor cells, promoting proliferation, survival and epithelial-to-mesenchymal transition (EMT), potentiating tumor development. These findings provide valuable mechanistic insights into the role of endothelial Jagged1 in promoting solid tumor development and support the notion that it may constitute a promising target for cancer therapy
Glycan microarray analysis of the carbohydrate-recognition specificity of native and recombinant forms of the lectin ArtinM
This article contains data related to the researc.h article entitled Yeast-derived ArtinM shares structure, carbohydrate recognition, and biological effects with native ArtinM by Cecílio et al. (2015) [1]. ArtinM, a D-mannose-binding lectin isolated from the seeds of Artocarpus heterophyllus, exerts immunomodulatory and regenerative activities through its Carbohydrate Recognition Domain (CRD) (Souza et al., 2013; Mariano et al., 2014 [2], [3]). The limited availability of the native lectin (n-ArtinM) led us to characterize a recombinant form of the protein, obtained by expression in Saccharomyces cerevisiae (y-ArtinM). We compared the carbohydrate-binding specificities of y-ArtinM and n-ArtinM by analyzing the binding of biotinylated preparations of the two lectin forms using a neoglycolipid (NGL)-based glycan microarray. Data showed that y-ArtinM mirrored the specificity exhibited by n-ArtinM
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
Qualidade de vida da criança com cardiopatia congénita: que instrumentos de avaliação?
A qualidade de vida da criança com cardiopatia congénita é uma preocupação para todos os profissionais de
saúde que diariamente desenvolvem actividades com estas crianças. Perceber com que qualidade de vida crescem
e se desenvolvem, é essencial para uma tomada de decisão consciente e individualizada relativamente ao tratamento
a instituir. Com o intuito de identificar escalas específicas para avaliação da sua qualidade de vida, foi
realizada pesquisa em bases de dados, da qual emergiram dois instrumentos: o ConQOL e o PCQLI. Estas ferramentas
de avaliação da qualidade de vida da criança com cardiopatia congénita apresentam duas versões adaptadas
às idades das crianças/adolescentes e uma delas contempla também a opinião dos pais relativa à qualidade
de vida dos filhos.The quality of life of children with congenital heart disease is a concern for all health professionals dealing, on a
daily basis, with these children. It is essential for a good decision-making and individualized treatment to follow,
to realize with which quality of life are they growing and developing. In order to identify speci$c scales for assessing
the quality of life, a survey and search in databases was conducted. From this survey and search two instruments
emerged: the ConQOL and PCQLI. These tools for assessing the quality of life of children with congenital
heart disease have two versions tailored to teens and children ages, and one of them also includes the parents’
opinion on the quality of life of their children.info:eu-repo/semantics/publishedVersio
Regulation of T cell response to leishmania antigens by determinants of histocompatibility leukocyte class I and II molecules
Peritubular Capillaries C4d Deposits in Renal Allograft Biopsies and Anti HLA I/II Alloantibodies Screening. Incidence and Clinical Importance
Aim: To characterise clinically the patients with C4d in peritubular capillaries deposits (C4dPTCD) and/or circulating anti-HLA class I/II alloantibodies. To determine the correlation between positive C4dPTCD and
circulating anti-HLA class I/II alloantibodies during episodes of graft dysfunction.
Subjects and Methods: C4d staining was performed in biopsies with available frozen tissue obtained between January 2004 and December 2006. The study was prospective from March 2005, when a serum sample
was obtained at the time of biopsy to detect circulating anti-HLA class I/II alloantibodies.
Results: We studied 109 biopsies in 86 cadaver renal transplant patients. Sixteen of these (14.7%) presented diffuse positive C4dPTCD. There was a 13.5% rate of +C4dPTCD incidence within the first six months of
transplantation and 16% after six months (p>0.05). Half of the +C4dPTCD in the first six months was associated with acute humoral rejection. After six months, the majority of +C4dPTCD (n=7/8) was present in biopsies
with evidence of interstitial fibrosis/tubular atrophy and/or transplant glomerulopathy. The C4dPTCD was more frequent in patients with positive anti-HCV antibodies(p<0.0001), a previous renal transplant (p=0.007), and with a panel reactivity antibody (PRA) ≥ 50%(p=0.0098). The anti-HCV+ patients had longer time on dialysis (p=0.0019) and higher PRA(p=0.005). Circulating anti-HLA I/II alloantibodies were screened in 46 serum samples. They were positive in 10.9% of samples, all obtained after six months post transplant. Circulating
alloantibodies were absent in 92.5% of the C4d negative biopsies.
Conclusion: We found an association between the presence of C4dPTCD and 2nd transplant recipients,higher PRA and the presence of anti-HCV antibodies.
The presence of HCV antibodies is not a risk factor for C4dPTCD per se, but appears to reflect longer time on dialysis and presensitisation. In renal dysfunction
a negative alloantibody screening is associated with a reduced risk of C4dPTCD (<10%)
Spillover events of rabbit haemorrhagic disease virus 2 (recombinant GI.4P-GI.2) from Lagomorpha to Eurasian badger
Rabbit haemorrhagic disease (RHD) is a major threat to domestic and wild European rabbits. Presently, in Europe, the disease is caused mainly by Rabbit haemorrhagic disease virus 2 (RHDV2/b or Lagovirus europaeus GI.2), the origin of which is still unclear, as no RHDV2 reservoir hosts were identified. After the RHDV2 emergence in 2010, viral RNA was detected in a few rodent species. Furthermore, RHDV2 was found to cause disease in some hare species resembling the disease in rabbits, evidencing the ability of the virus to cross the species barrier.
In this study, through molecular, histopathologic, antigenic and morphological evidences, we demonstrate the presence and replication of RHDV2 in Eurasian badgers (Meles meles) found dead in the district of Santarém, Portugal, between March 2017 and January 2020. In two of these seven animals, we further classify the RHDV2 as a Lagovirus europaeus recombinant GI.4P‐GI.2.
Our results indicate that Meles meles is susceptible to RHDV2, developing systemic infection, and excreting the virus in the faeces. Given the high viral loads seen in several organs and matrices, we believe that transmission to the wild rabbit is likely.
Furthermore, transmission electron microscopy data shows the presence of Calicivirus compatible virions in the nucleus of hepatocytes, which has not been demonstrated before and constitutes a paradigm shift for caliciviruses’s replication cycle
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