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1.
J Med Syst ; 43(7): 213, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154515

RESUMO

The QoE measurement has become a novel theme today. To achieve a quality service and minimize the negative impact that traffic on network can cause, it's very important to manage the devices that intervene in this service. Hence, the QoE evaluation allows obtaining benefits both customers and service providers. The main objective of this paper is to measure QoE of a teleconsultation application in Mental Health named Psiconnect, using an approach based on pentagram model. For the QoE evaluation of Psiconnect application we used the pentagram model based on the measurement of 5 factors (integrality, retainability, availability, usability, and instantaneousness). This model allows to design quantifiable metrics for quality evaluations. Using the model cited the value of QoE for Psiconnect is 1.793 (between 1.6 and 1.8). Comparing with Mean Opinion Scores (MOS) test, some users are dissatisfied with the use of the application although the result is near 1.8, so the most of users are satisfied with the use of teleconsultation service based in Skype in the Psiconnect app. There are different models to measure QoE having into account subjective parameters. This is important an estimation of QoE in a quantitative form. Other models can be used to improve the quality of apps.


Assuntos
Saúde Mental , Aplicativos Móveis , Satisfação do Paciente , Qualidade da Assistência à Saúde , Consulta Remota/métodos , Humanos , Indicadores de Qualidade em Assistência à Saúde , Consulta Remota/instrumentação , Consulta Remota/normas
2.
J Infect Dis ; 217(9): 1472-1480, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29390091

RESUMO

In this study, we identified, at the single-cell level, naturally induced cytokine-producing circulating cells (CPCCs) in children with dengue virus (DENV) infection ranging clinically from mild to severe disease. Tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) CPCCs were detected in children with primary or secondary acute dengue virus (DENV) infection, and the pattern of these cytokines was similar to that seen in the supernatant of cultured peripheral blood mononuclear cells and partially comparable to that found in plasma. Monocytes, B cells, and myeloid dendritic cells (mDCs) were the primary CPCCs detected, and the frequency of mDCs was significantly higher in severe disease. B cells isolated from children with dengue spontaneously secreted TNF-α, IL-6, and interleukin 10, and supernatants from cultures of purified B cells induced activation of allogeneic T cells, supporting an antibody-independent function of these cells during DENV infection. Thus, CPCCs could be a new immune parameter with potential use to evaluate pathogenesis in this infection.


Assuntos
Linfócitos B/metabolismo , Citocinas/metabolismo , Células Dendríticas/metabolismo , Dengue/imunologia , Monócitos/metabolismo , Criança , Dengue/metabolismo , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Masculino
3.
J Med Syst ; 43(1): 11, 2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30519972

RESUMO

Internet of Things (IoT) has emerged as a new paradigm today, connecting a variety of physical and virtual elements integrated with electronic components, sensors, actuators and software to collect and exchange data. IoT is gaining increasing attention as a priority research topic in the Health sector in general and in specific areas such as Mental Health. The main objective of this paper is to show a review of the existing research works in the literature, referring to the main IoT services and applications in Mental Health diseases. The scientific databases used to carry out the review are Google Scholar, IEEE Xplore, PubMed, Science Direct, and Web of Science, taking into account as date of publication the last 10 years, from 2008 to the present. Several search criteria were established such as "IoT OR Internet of Things AND (Application OR Service) AND Mental Health" selecting the most interesting articles. A total of 51 articles were found on IoT-based services and applications in Mental Health, of which 14 have been identified as relevant works in mental health. Many of the publications (more than 60%) found show the applications developed for monitoring patients with mental disorders through sensors and networked devices. The inclusion of the new IoT technology in Health brings many benefits in terms of monitoring, welfare interventions and providing alert and information services. In pathologies such as Mental Health is a vital factor to improve the patient life quality and effectiveness of the medical service.


Assuntos
Internet , Saúde Mental , Bases de Dados Factuais , Humanos , Software
4.
Plant Cell ; 26(5): 2098-2113, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24876252

RESUMO

The production of the sperm cells in angiosperms requires coordination of cell division and cell differentiation. In Arabidopsis thaliana, the germline-specific MYB protein DUO1 integrates these processes, but the regulatory hierarchy in which DUO1 functions is unknown. Here, we identify an essential role for two germline-specific DUO1 target genes, DAZ1 and DAZ2, which encode EAR motif-containing C2H2-type zinc finger proteins. We show that DAZ1/DAZ2 are required for germ cell division and for the proper accumulation of mitotic cyclins. Importantly, DAZ1/DAZ2 are sufficient to promote G2- to M-phase transition and germ cell division in the absence of DUO1. DAZ1/DAZ2 are also required for DUO1-dependent cell differentiation and are essential for gamete fusion at fertilization. We demonstrate that the two EAR motifs in DAZ1/DAZ2 mediate their function in the male germline and are required for transcriptional repression and for physical interaction with the corepressor TOPLESS. Our findings uncover an essential module in a regulatory hierarchy that drives mitotic transition in male germ cells and implicates gene repression pathways in sperm cell formation and fertility.

5.
Cell Commun Signal ; 14: 5, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26861207

RESUMO

BACKGROUND: Growth factors induce a characteristically short-lived Ras activation in cells emerging from quiescence. Extensive work has shown that transient as opposed to sustained Ras activation is critical for the induction of mitogenic programs. Mitogen-induced accumulation of active Ras-GTP results from increased nucleotide exchange driven by the nucleotide exchange factor Sos. In contrast, the mechanism accounting for signal termination and prompt restoration of basal Ras-GTP levels is unclear, but has been inferred to involve feedback inhibition of Sos. Remarkably, how GTP-hydrolase activating proteins (GAPs) participate in controlling the rise and fall of Ras-GTP levels is unknown. RESULTS: Monitoring nucleotide exchange of Ras in permeabilized cells we find, unexpectedly, that the decline of growth factor-induced Ras-GTP levels proceeds in the presence of unabated high nucleotide exchange, pointing to GAP activation as a major mechanism of signal termination. Experiments with non-hydrolysable GTP analogues and mathematical modeling confirmed and rationalized the presence of high GAP activity as Ras-GTP levels decline in a background of high nucleotide exchange. Using pharmacological and genetic approaches we document a raised activity of the neurofibromatosis type I tumor suppressor Ras-GAP neurofibromin and an involvement of Rsk1 and Rsk2 in the down-regulation of Ras-GTP levels. CONCLUSIONS: Our findings show that, in addition to feedback inhibition of Sos, feedback stimulation of the RasGAP neurofibromin enforces termination of the Ras signal in the context of growth-factor signaling. These findings ascribe a precise role to neurofibromin in growth factor-dependent control of Ras activity and illustrate how, by engaging Ras-GAP activity, mitogen-challenged cells play safe to ensure a timely termination of the Ras signal irrespectively of the reigning rate of nucleotide exchange.


Assuntos
Ativação Enzimática , Fator de Crescimento Epidérmico/metabolismo , Neurofibromina 1/metabolismo , Transdução de Sinais , Proteínas ras/metabolismo , Animais , Linhagem Celular , Guanosina Trifosfato/metabolismo , Células HEK293 , Células HeLa , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Fosforilação , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteína Son Of Sevenless de Drosófila/metabolismo
6.
Biol Chem ; 396(8): 831-48, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25781681

RESUMO

Ras is a prototypical small G-protein and a central regulator of growth, proliferation and differentiation processes in virtually every nucleated cell. As such, Ras becomes engaged and activated by multiple growth factors, mitogens, cytokines or adhesion receptors. Ras activation comes about by changes in the steady-state equilibrium between the inactive guanosine diphosphate (GDP)-bound and active guanosine triphosphate (GTP)-bound states of Ras, resulting in the mostly transient accumulation of Ras-GTP. Three decades of intense Ras research have disclosed various families of guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs) as the two principal regulatory elements of the Ras-GDP/GTP loading status. However, with the possible exception of the GEF Sos, we still have only a rudimentary knowledge of the precise role played by many GEF and GAP members in the signalling network upstream of Ras. As for GAPs, we even lack the fundamental understanding of whether they function as genuine signal transducers in the context of growth factor-elicited Ras activation or rather act as passive modulators of the Ras-GDP/GTP cycle. Here we sift through the large body of Ras literature and review the relevant data for understanding the participation and precise role played by GEFs and GAPs in the process of Ras activation.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas ras/metabolismo , Animais , Fatores de Troca do Nucleotídeo Guanina/genética , Guanosina Trifosfato/metabolismo , Humanos , Ligação Proteica , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas ras/genética
7.
Viruses ; 16(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38932111

RESUMO

Rotavirus infection continues to be a significant public health problem in developing countries, despite the availability of several vaccines. The efficacy of oral rotavirus vaccines in young children may be affected by significant immunological differences between individuals in early life and adults. Therefore, understanding the dynamics of early-life systemic and mucosal immune responses and the factors that affect them is essential to improve the current rotavirus vaccines and develop the next generation of mucosal vaccines. This review focuses on the advances in T-cell development during early life in mice and humans, discussing how immune homeostasis and response to pathogens is established in this period compared to adults. Finally, the review explores how this knowledge of early-life T-cell immunity could be utilized to enhance current and novel rotavirus vaccines.


Assuntos
Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Linfócitos T , Vacinas contra Rotavirus/imunologia , Vacinas contra Rotavirus/administração & dosagem , Humanos , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/imunologia , Animais , Rotavirus/imunologia , Linfócitos T/imunologia , Administração Oral , Imunidade nas Mucosas , Camundongos
8.
J Virol ; 86(19): 10829-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22855480

RESUMO

Protective immunity to rotavirus (RV) is primarily mediated by antibodies produced by RV-specific memory B cells (RV-mBc). Of note, most of these cells express IgM, but the function of this subset is poorly understood. Here, using limiting dilution assays of highly sort-purified human IgM(+) mBc, we found that 62% and 21% of total (non-antigen-specific) IgM(+) and RV-IgM(+) mBc, respectively, switched in vitro to IgG production after polyclonal stimulation. Moreover, in these assays, the median cloning efficiencies of total IgM(+) (17%) and RV-IgM(+) (7%) mBc were lower than those of the corresponding switched (IgG(+) IgA(+)) total (34%) and RV-mBc (17%), leading to an underestimate of their actual frequency. In order to evaluate the in vivo role of IgM(+) RV-mBc in antiviral immunity, NOD/Shi-scid interleukin-2 receptor-deficient (IL-2Rγ(null)) immunodeficient mice were adoptively transferred highly purified human IgM(+) mBc and infected with virulent murine rotavirus. These mice developed high titers of serum human RV-IgM and IgG and had significantly lower levels than control mice of both antigenemia and viremia. Finally, we determined that human RV-IgM(+) mBc are phenotypically diverse and significantly enriched in the IgM(hi) IgD(low) subset. Thus, RV-IgM(+) mBc are heterogeneous, occur more frequently than estimated by traditional limiting dilution analysis, have the capacity to switch Ig class in vitro as well as in vivo, and can mediate systemic antiviral immunity.


Assuntos
Imunoglobulina M/química , Rotavirus/metabolismo , Animais , Linfócitos B/citologia , Separação Celular , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática/métodos , Citometria de Fluxo , Humanos , Imunoglobulina A/química , Imunoglobulina D/química , Imunoglobulina G , Imunoglobulina M/metabolismo , Memória Imunológica , Subunidade gama Comum de Receptores de Interleucina/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Fenótipo , Infecções por Rotavirus/metabolismo
10.
Front Immunol ; 14: 1241038, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37575243

RESUMO

The SARS CoV-2 antibody and CD4+ T cell responses induced by natural infection and/or vaccination decline over time and cross-recognize other viral variants at different levels. However, there are few studies evaluating the levels and durability of the SARS CoV-2-specific antibody and CD4+ T cell response against the Mu, Gamma, and Delta variants. Here, we examined, in two ambispective cohorts of naturally-infected and/or vaccinated individuals, the titers of anti-RBD antibodies and the frequency of SARS-CoV-2-specific CD4+ T cells up to 6 months after the last antigen exposure. In naturally-infected individuals, the SARS-CoV-2 antibody response declined 6 months post-symptoms onset. However, the kinetic observed depended on the severity of the disease, since individuals who developed severe COVID-19 maintained the binding antibody titers. Also, there was detectable binding antibody cross-recognition for the Gamma, Mu, and Delta variants, but antibodies poorly neutralized Mu. COVID-19 vaccines induced an increase in antibody titers 15-30 days after receiving the second dose, but these levels decreased at 6 months. However, as expected, a third dose of the vaccine caused a rise in antibody titers. The dynamics of the antibody response upon vaccination depended on the previous SARS-CoV-2 exposure. Lower levels of vaccine-induced antibodies were associated with the development of breakthrough infections. Vaccination resulted in central memory spike-specific CD4+ T cell responses that cross-recognized peptides from the Gamma and Mu variants, and their duration also depended on previous SARS-CoV-2 exposure. In addition, we found cross-reactive CD4+ T cell responses in unexposed and unvaccinated individuals. These results have important implications for vaccine design for new SARS-CoV-2 variants of interest and concern.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Vacinas contra COVID-19 , Colômbia/epidemiologia , Linfócitos T , Anticorpos Antivirais , Linfócitos T CD4-Positivos
11.
Cell Immunol ; 272(2): 154-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22082567

RESUMO

We have previously shown that human myeloid dendritic cells treated with purified rotavirus induce an allogenic Th1 response. To determine if rotavirus in the context of an intestinal microenvironment modulates the function of dendritic cells, we treated these cells with supernatants from non-infected or infected Caco-2 cells and studied their capacity to promote Th1 or Th2 responses. Dendritic cells treated with supernatants from rotavirus-infected Caco-2 cells promoted a significantly lower Th1 response, in comparison with those treated with purified rotavirus. We wanted to establish if TGF-ß1, induced, or TSLP, not induced, during rotavirus infection, could mediate this effect. Neutralization of TGF-ß but not TSLP in the supernatant prior to treatment of dendritic cells increased their capacity to promote a Th1 response. The results suggest that the TGF-ß1 induced by rotavirus could be an immune evasion mechanism, and may partially explain the poor rotavirus-specific T cell response we have previously evidenced.


Assuntos
Células Dendríticas/imunologia , Fatores Imunológicos/imunologia , Células Mieloides/imunologia , Infecções por Rotavirus/imunologia , Rotavirus/imunologia , Células Th1/imunologia , Antígeno B7-2/genética , Antígeno B7-2/imunologia , Linfócitos T CD4-Positivos/imunologia , Células CACO-2 , Microambiente Celular/genética , Microambiente Celular/imunologia , Técnicas de Cocultura , Citocinas/genética , Citocinas/imunologia , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Humanos , RNA Mensageiro/genética , Células Th2/imunologia , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/imunologia , Células Tumorais Cultivadas , Linfopoietina do Estroma do Timo
12.
J Virol ; 84(9): 4543-55, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20164228

RESUMO

We have shown previously that rotavirus (RV) can infect murine intestinal B220(+) cells in vivo (M. Fenaux, M. A. Cuadras, N. Feng, M. Jaimes, and H. B. Greenberg, J. Virol. 80:5219-5232, 2006) and human blood B cells in vitro (M. C. Mesa, L. S. Rodriguez, M. A. Franco, and J. Angel, Virology 366:174-184, 2007). However, the effect of RV on B cells, especially those present in the human intestine, the primary site of RV infection, is unknown. Here, we compared the effects of the in vitro RV infection of human circulating (CBC) and intestinal B cells (IBC). RV infected four times more IBC than CBC, and in both types of B cells the viral replication was highly restricted to the memory subset. RV induced cell death in 30 and 3% of infected CBC and IBC, respectively. Moreover, RV induced activation and differentiation into antibody-secreting cells (ASC) of CBC but not IBC when the B cells were present with other mononuclear cells. However, RV did not induce these effects in purified CBC or IBC, suggesting the participation of other cells in activating and differentiating CBC. RV infection was associated with enhanced interleukin-6 (IL-6) production by CBC independent of viral replication. The infection of the anti-B-cell receptor, lipopolysaccharide, or CpG-stimulated CBC reduced the secretion of IL-6 and IL-8 and decreased the number of ASC. These inhibitory effects were associated with an increase in viral replication and cell death and were observed in polyclonally stimulated CBC but not in IBC. Thus, RV differentially interacts with primary human B cells depending on their tissue of origin and differentiation stage, and it affects their capacity to modulate the local and systemic immune responses.


Assuntos
Anticorpos Antivirais/biossíntese , Linfócitos B/imunologia , Linfócitos B/virologia , Rotavirus/imunologia , Adulto , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/virologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/virologia , Morte Celular , Diferenciação Celular , Células Cultivadas , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Adulto Jovem
14.
Viral Immunol ; 20(2): 300-11, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17603846

RESUMO

In a double blind trial, 319 fully immunized children received two doses of either placebo or 10(6.7) focus-forming units of the attenuated RIX4414 human rotavirus (RV) vaccine ("all-in-one" formulation). Plasma RV-specific IgA (RV IgA), stool RV IgA, and circulating total and RV memory B cells (CD19+ IgD+/- CD27+) with an intestinal homing phenotype (alpha4beta7+ CCR9+/-) were measured, after the first and second doses, as potential correlates of protection. After the first and/or second dose, 54% of vaccinees and 13% of placebo recipients had plasma RV IgA. Before vaccination, most (95%) of the children (of both study groups) were breast-fed and had stool RV IgA (68.64%). Coproconversion (4-fold increase) after the first and/or second dose was observed in 32.7% of vaccinees and 17.4% of placebo recipients. No significant difference was seen when comparing the frequencies of any subset of memory B cells between vaccinees and placebo recipients. Statistically significant weak correlations were found between plasma RV IgA titers and coproconversion, and several subsets of memory B cells. The vaccine provided 74.8% protection (95% confidence interval, 30.93-92.62) against any RV gastroenteritis and 100% protection (95% confidence interval, 14.53-100) against severe RV gastroenteritis. When vaccinees and placebo recipients were considered together, a correlation was found between protection from disease and plasma RV IgA measured after dose 2 and RV memory (IgD- CD27+ alpha4beta7+ CCR9+) circulating B cells measured after dose 1. However, the correlation coefficients for both tests were low (<0.2), suggesting that other factors are important in explaining protection from disease.


Assuntos
Subpopulações de Linfócitos B/imunologia , Imunoglobulina A/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Rotavirus/imunologia , Vacinas Atenuadas/imunologia , Subpopulações de Linfócitos B/metabolismo , Colômbia , Método Duplo-Cego , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/metabolismo , Memória Imunológica , Lactente , Masculino , Vacinas Atenuadas/uso terapêutico
15.
JMIR Mhealth Uhealth ; 5(10): e130, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29017992

RESUMO

BACKGROUND: The best manner to prevent suicide is to recognize suicidal signs and signals, and know how to respond to them. OBJECTIVE: We aim to study the existing mobile apps for suicide prevention in the literature and the most commonly used virtual stores. METHODS: Two reviews were carried out. The first was done by searching the most commonly used commercial app stores, which are iTunes and Google Play. The second was a review of mobile health (mHealth) apps in published articles within the last 10 years in the following 7 scientific databases: Science Direct, Medline, PsycINFO, Embase, The Cochrane Library, IEEE Xplore, and Google Scholar. RESULTS: A total of 124 apps related to suicide were found in the cited virtual stores but only 20 apps were specifically designed for suicide prevention. All apps were free and most were designed for Android. Furthermore, 6 relevant papers were found in the indicated scientific databases; in these studies, some real experiences with physicians, caregivers, and families were described. The importance of these people in suicide prevention was indicated. CONCLUSIONS: The number of apps regarding suicide prevention is small, and there was little information available from literature searches, indicating that technology-based suicide prevention remains understudied. Many of the apps provided no interactive features. It is important to verify the accuracy of the results of different apps that are available on iOS and Android. The confidence generated by these apps can benefit end users, either by improving their health monitoring or simply to verify their body condition.

16.
Nat Rev Dis Primers ; 3: 17083, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29119972

RESUMO

Rotavirus infections are a leading cause of severe, dehydrating gastroenteritis in children <5 years of age. Despite the global introduction of vaccinations for rotavirus over a decade ago, rotavirus infections still result in >200,000 deaths annually, mostly in low-income countries. Rotavirus primarily infects enterocytes and induces diarrhoea through the destruction of absorptive enterocytes (leading to malabsorption), intestinal secretion stimulated by rotavirus non-structural protein 4 and activation of the enteric nervous system. In addition, rotavirus infections can lead to antigenaemia (which is associated with more severe manifestations of acute gastroenteritis) and viraemia, and rotavirus can replicate in systemic sites, although this is limited. Reinfections with rotavirus are common throughout life, although the disease severity is reduced with repeat infections. The immune correlates of protection against rotavirus reinfection and recovery from infection are poorly understood, although rotavirus-specific immunoglobulin A has a role in both aspects. The management of rotavirus infection focuses on the prevention and treatment of dehydration, although the use of antiviral and anti-emetic drugs can be indicated in some cases.


Assuntos
Infecções por Rotavirus , Humanos , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/terapia
17.
PLoS One ; 11(8): e0161795, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27560782

RESUMO

The response of antibody-secreting cells (ASC) induced by dengue has only recently started to be characterized. We propose that young age and previous infections could be simple factors that affect this response. Here, we evaluated the primary and secondary responses of circulating ASC in infants (6-12 months old) and children (1-14 years old) infected with dengue showing different degrees of clinical severity. The ASC response was delayed and of lower magnitude in infants, compared with older children. In primary infection (PI), the total and envelope (E) protein-specific IgM ASC were dominant in infants but not in children, and a negative correlation was found between age and the number of IgM ASC (rho = -0.59, P = 0.03). However, infants with plasma dengue-specific IgG detectable in the acute phase developed an intense ASC response largely dominated by IgG and comparable to that of children with secondary infection (SI). IgM and IgG produced by ASC circulating in PI or SI were highly cross-reactive among the four serotypes. Dengue infection caused the disturbance of B cell subsets, particularly a decrease in the relative frequency of naïve B cells. Higher frequencies of total and E protein-specific IgM ASC in the infants and IgG in the children were associated with clinically severe forms of infection. Therefore, the ASC response induced by dengue is highly influenced by the age at which infection occurs and previous immune status, and its magnitude is a relevant element in the clinical outcome. These results are important in the search for correlates of protection and for determining the ideal age for vaccinating against dengue.


Assuntos
Anticorpos Antivirais/imunologia , Células Produtoras de Anticorpos/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Proteínas do Envelope Viral/imunologia , Adolescente , Fatores Etários , Anticorpos Antivirais/sangue , Células Produtoras de Anticorpos/virologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/virologia , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Dengue/sangue , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/fisiologia , ELISPOT , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Lactente , Masculino , Sorogrupo
18.
Hum Immunol ; 77(7): 594-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27166175

RESUMO

In addition to previously studied immunological variables, the relative expression of IFNGR2, IFNAR1, CD18, and CD275 (all encoded in chromosome 21) on circulating leucocytes and multifunctional T cells (evaluated by an intracellular cytokine/proliferation assay) were compared between children with Down syndrome (DS) and healthy controls (HC). As previously reported, numbers of lymphocytes, CD4(+) T cells, Treg cells, B cells, and levels of serum IgM were decreased, and levels of IgG and IgA were increased in children with DS. Moreover, the relative expression of CD18 on T and B cells (previously and not previously reported, respectively) were elevated in DS children (p⩽0.01). Age and numbers of B and Treg cells moderately correlated with retrospectively identified infection related hospitalizations (rho: 0.300-0.460, p⩽0.003). Age and the numbers of Treg cells also correlated with prospectively identified infection related hospitalizations. Future studies are necessary to clarify the role of these parameters in the immunity of DS patients.


Assuntos
Linfócitos B/imunologia , Cromossomos Humanos Par 21/genética , Síndrome de Down/imunologia , Hospitalização/estatística & dados numéricos , Infecções/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Adolescente , Antígenos CD18/metabolismo , Proliferação de Células , Criança , Pré-Escolar , Citocinas/metabolismo , Síndrome de Down/complicações , Síndrome de Down/epidemiologia , Feminino , Humanos , Ligante Coestimulador de Linfócitos T Induzíveis/metabolismo , Lactente , Infecções/complicações , Infecções/epidemiologia , Ativação Linfocitária , Masculino , Receptor de Interferon alfa e beta/genética , Receptor de Interferon alfa e beta/metabolismo , Receptores de Interferon/genética , Receptores de Interferon/metabolismo
19.
PLoS One ; 10(10): e0139718, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26439739

RESUMO

Circulating human IgM expressing memory B cells have been incompletely characterized. Here, we compared the phenotype and in vitro functional response (capacity to proliferate and differentiate to antibody secreting cells) in response to CpG and a cytokine cocktail (IL-2, IL-6, and IL-10) of sorted naïve B cells, IgM memory B cells and isotype-switched circulating memory B cells. Compared to naïve B cells, IgM memory B cells had lower integrated mean fluorescence intensity (iMFI) of BAFF-R, CD38, CD73, and IL-21R, but higher iMFI of CD95, CD11c, TLR9, PD-1, and CD122. Compared to switched memory B cells, IgM memory B cells had higher iMFI of BAFF-R, PD-1, IL-21R, TLR9, and CD122, but lower iMFI of CD38, CD95, and CD73. Four days after receiving the CpG/cytokine cocktail, higher frequencies of IgM than switched memory B cells-and these in turn greater than naïve cells-proliferated and differentiated to antibody secreting cells. At this time point, a small percentage (median of 7.6%) of stimulated IgM memory B cells changed isotype to IgG. Thus, among the heterogeneous population of human circulating IgM memory B cells a subset is capable of a rapid functional response to a CpG/cytokine stimulus in vitro.


Assuntos
Subpopulações de Linfócitos B/citologia , Linfócitos B/citologia , Diferenciação Celular/imunologia , Proliferação de Células/fisiologia , Imunoglobulina M/imunologia , Subpopulações de Linfócitos B/efeitos dos fármacos , Subpopulações de Linfócitos B/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Switching de Imunoglobulina , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/imunologia , Interleucina-10/farmacologia , Interleucina-2/farmacologia , Interleucina-6/farmacologia
20.
Cell Stress Chaperones ; 20(4): 697-708, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25975376

RESUMO

Previously, we showed that infecting human intestinal epithelial cells (Caco-2) with rotavirus (RV) increases the release of extracellular vesicles (EVs) with an immunomodulatory function that, upon concentration at 100,000×g, present buoyant densities on a sucrose gradient of between 1.10 to 1.18 g/ml (characteristic of exosomes) and higher than 1.24 g/ml (proposed for apoptotic bodies). The effect of cellular death induced by RV on the composition of these EV is unknown. Here, we evaluated exosome (CD63, Hsc70, and AChE) and apoptotic body (histone H3) markers in EVs isolated by differential centrifugation (4000×g, 10,000×g, and 100,000×g) or filtration/ultracentrifugation (100,000×g) protocols. When we infected cells in the presence of caspase inhibitors, Hsc70 and AChE diminished in EVs obtained at 100,000×g, but not in EVs obtained at 4000×g or 10,000×g. In addition, caspase inhibitors decreased CD63 and AChE in vesicles with low and high buoyant densities. Without caspase inhibitors, RV infection increased exosome markers in all of the EVs obtained by differential centrifugation. However, CD63 preferentially localized in the 100,000×g fraction and H3 only increased in EVs concentrated at 100,000×g and with high buoyant densities on a sucrose gradient. Thus, RV infection increases the release of EVs that, upon concentration at 100,000×g, are composed by exosomes and apoptotic bodies, which can partially be separated using sucrose gradients.


Assuntos
Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Rotavirus/fisiologia , Acetilcolinesterase/metabolismo , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Células CACO-2 , Inibidores de Caspase/toxicidade , Vesículas Extracelulares/virologia , Proteínas de Choque Térmico HSC70/metabolismo , Histonas/metabolismo , Humanos , Tetraspanina 30/metabolismo , Ultracentrifugação , Replicação Viral/efeitos dos fármacos
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