182 research outputs found
Henoch-Schönlein purpura: recurrence and chronicity
OBJECTIVES: To describe a group of patients treated at our service for Henoch-Schönlein purpura, with emphasis on recurrent and chronic cases, and to compare clinical and demographic characteristics of patients with monocyclic and recurrent disease. METHODS: Data on 67 patients who had been treated since disease onset were analyzed. Twelve patients were excluded because they failed to return for follow-up consultations after less than 3 months, leaving a total of 55 children in the study sample. Recurrence was defined as the presence of a fresh episode after a period of at least 3 months without symptoms, and cases were defined as chronic when cutaneous, abdominal and renal manifestations persisted for a period of 12 months or more. RESULTS: Recurrence was observed in 8/55 patients (14.4%) and four cases were chronic (7.2%). In 29/55 patients (52.7%), infection was identified as the trigger factor. A monocyclic clinical course was observed in 43 patients (26 of whom were girls, with a mean age of 5.4 years). Gastrointestinal and renal involvement was observed in 55.8 and 20.9% of patients, respectively. Among the 12 patients with recurrent or chronic Henoch-Schönlein purpura, three had arthritis, four exhibited signs and symptoms of abdominal involvement and seven of kidney disease: microscopic hematuria in five, macroscopic hematuria in one and hematuria with proteinuria in one other. Late onset was the only variable related to recurrence (p < 0.05). CONCLUSIONS: As is observed in medical literature, monocyclic cases are more common among children with early onset disease. Patients with Henoch-Schönlein purpura should be followed over the long term, since recurrent and chronic cases account for more than 20% of the total.OBJETIVOS: Descrever um grupo de pacientes com púrpura de Henoch-Schönlein seguido em nosso serviço, com ênfase nos casos recorrentes e crônicos, e comparar pacientes com doença monocÃclica ou recorrente segundo caracterÃsticas clÃnicas e demográficas. MÉTODOS: Foram avaliados dados de 67 pacientes atendidos desde o inÃcio da doença. Doze pacientes foram excluÃdos, pois abandonaram o seguimento antes de 3 meses de acompanhamento, sendo incluÃdas 55 crianças no estudo. Recorrência foi definida pela presença de novo quadro após um perÃodo de 3 meses sem sintomas, e cronicidade como persistência de manifestações cutâneas, abdominais e renais por um perÃodo ≥ 12 meses. RESULTADOS: Foi observada recorrência em 8/55 pacientes (14,4 %) e cronicidade em quatro (7,2%). Em 29/55 pacientes (52,7%), foi constatada infecção como fator desencadeante. Curso monocÃclico esteve presente em 43 pacientes (26 meninas, média de idade de 5,4 anos). Acometimento gastrointestinal e renal foi observado em 55,8 e 20,9% dos pacientes, respectivamente. Dentre os 12 pacientes com púrpura de Henoch-Schönlein recorrente ou crônica, três apresentaram artrite, quatro tiveram sinais e sintomas de comprometimento abdominal e sete de doença renal: hematúria microscópica em cinco, hematúria macroscópica em um e hematúria com proteinúria em um paciente. Idade de inÃcio tardia foi a única variável relacionada com a presença de recorrência (p < 0,05). CONCLUSÕES: Como observado na literatura médica, o curso monocÃclico é mais freqüente nas crianças com inÃcio da doença em idade mais precoce. Pacientes com púrpura de Henoch-Schönlein devem ser seguidos a longo prazo, uma vez que recorrências e/ou cronicidade são observadas em mais de 20% dos casos.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PediatriaUNIFESP-EPM Departamento de PediatriaUNIFESP, EPM, Depto. de PediatriaUNIFESP, EPM Depto. de PediatriaSciEL
Evolution of Human Memory B Cells From Childhood to Old Age
High quality medical assistance and preventive strategies, including pursuing a healthy lifestyle, result in a progressively growing percentage of older people. The population and workforce is aging in all countries of the world. It is widely recognized that older individuals show an increased susceptibility to infections and a reduced response to vaccination suggesting that the aged immune system is less able to react and consequently protect the organism. The SARS-CoV-2 pandemic is dramatically showing us that the organism reacts to novel pathogens in an age-dependent manner. The decline of the immune system observed in aging remains unclear. We aimed to understand the role of B cells. We analyzed peripheral blood from children (4-18 years); young people (23-60 years) and elderly people (65-91 years) by flow cytometry. We also measured antibody secretion by ELISA following a T-independent stimulation. Here we show that the elderly have a significant reduction of CD27dull memory B cells, a population that bridges innate and adaptive immune functions. In older people, memory B cells are mostly high specialized antigen-selected CD27bright. Moreover, after in vitro stimulation with CpG, B cells from older individuals produced significantly fewer IgM and IgA antibodies compared to younger individuals. Aging is a complex process characterized by a functional decline in multiple physiological systems. The immune system of older people is well equipped to react to often encountered antigens but has a low ability to respond to new pathogens
Ordered mesoporous silica materials for protein adsorption
Lysozyme and BSA were used, as model proteins of considerably different dimensions, in
order to evaluate the influence of the distinct pore structural characteristics of three types of ordered
mesoporous silica materials (MCF, SBA-15 and MCM-41) on protein adsorption. Characterisation
by X ray diffraction and nitrogen adsorption at 77K revealed the typical pore structural features of
each type of material. The maximum of the pore size distributions indicated that the width of the
windows of MCF (2) (mesitylene/P123 of 2) was larger than the pore diameter of the unidirectional
tubular pores of SBA-15. All the materials presented similar small external surface areas but high
pore volumes, with that of MCF (2) being the highest. The adsorption of lysozyme at pH=8
increased in the order MCM-41<< SBA-15< MCF (2), and the uptakes were well above those of
BSA at pH=5. Although BSA is not completely excluded from the mesopores of SBA-15 and
MCF (2), as happens with MCM-41, the adsorption occurs to a very limited extent. The overall
behaviour of these SBA-15 and MCF (2) samples was not significantly different and both revealed
potential for the separation of these proteins
New cross-talk layer between ultraconserved non-coding RNAs, microRNAs and polycomb protein YY1 in bladder cancer
MicroRNAs (miRNAs) are highly conserved elements in mammals, and exert key regulatory functions. Growing evidence shows that miRNAs can interact with another class of non-coding RNAs, so-called transcribed ultraconserved regions (T-UCRs), which take part in transcriptional, post-transcriptional and epigenetic regulation processes. We report here the interaction of miRNAs and T-UCRs as a network modulating the availability of these non-coding RNAs in bladder cancer cells. In our cell system, antagomiR-596 increased the expression of T-UCR 201+. Moreover, T-UCR 8+ silencing increased miR-596 expression, which in turn reduced total T-UCR 283+, showing that the perturbation of one element in this network changes the expression of other interactors. In addition, we identify the polycomb protein Yin Yang 1 (YY1) as mediator of binding between miR-596 and T-UCR 8+. These new findings describe for the first time a network between T-UCRs, miRNAs and YY1 protein, highlighting the existence of an additional layer of gene expression regulation
Different Innate and Adaptive Immune Responses to SARS-CoV-2 Infection of Asymptomatic, Mild, and Severe Cases
SARS-CoV-2 is a novel coronavirus, not encountered before by humans. The wide spectrum of clinical expression of SARS-CoV-2 illness suggests that individual immune responses to SARS-CoV-2 play a crucial role in determining the clinical course after first infection. Immunological studies have focused on patients with moderate to severe disease, demonstrating excessive inflammation in tissues and organ damage. In order to understand the basis of the protective immune response in COVID-19, we performed a longitudinal follow-up, flow-cytometric and serological analysis of innate and adaptive immunity in 64 adults with a spectrum of clinical presentations: 28 healthy SARS-CoV-2-negative contacts of COVID-19 cases; 20 asymptomatic SARS-CoV-2-infected cases; eight patients with Mild COVID-19 disease and eight cases of Severe COVID-19 disease. Our data show that high frequency of NK cells and early and transient increase of specific IgA, IgM and, to a lower extent, IgG are associated with asymptomatic SARS-CoV-2 infection. By contrast, monocyte expansion and high and persistent levels of IgA and IgG, produced relatively late in the course of the infection, characterize severe disease. Modest increase of monocytes and different kinetics of antibodies are detected in mild COVID-19. The importance of innate NK cells and the short-lived antibody response of asymptomatic individuals and patients with mild disease suggest that only severe COVID-19 may result in protective memory established by the adaptive immune response
Isogeometric analysis for fluid shear stress in cancer cells
Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação ArtÃstica (IDI&CA) 2018 do Instituto Politécnico de Lisboa. Código de referência IPL/2018/IGACFC_ISELThe microenvironment of the tumor is a key factor regulating tumor cell invasion and metastasis. The effects of physical factors in tumorigenesis is unclear. Shear stress, induced by liquid flow, plays a key role in proliferation, apoptosis, invasion, and metastasis of tumor cells. The mathematical models have the potential to elucidate the metastatic behavior of the cells’ membrane exposed to these microenvironment forces. Due to the shape configuration of the cancer cells, Non-uniform Rational B-splines (NURBS) lines are very adequate to define its geometric model. The Isogeometric Analysis allows a simplified transition of exact CAD models into the analysis avoiding the geometrical discontinuities of the traditional Galerkin traditional techniques. In this work, we use an isogeometric analysis to model the fluid-generated forces that tumor cells are exposed to in the vascular and tumor microenvironments, in the metastatic process. Using information provided by experimental tests in vitro, we present a suite of numerical experiments which indicate, for standard configurations, the metastatic behavior of cells exposed to such forces. The focus of this paper is strictly on geometrical sensitivities to the shear stress’ exhibition for the cell membrane, this being its innovation.info:eu-repo/semantics/publishedVersio
Different Innate and Adaptive Immune Responses to SARS-CoV-2 Infection of Asymptomatic, Mild, and Severe Cases
SARS-CoV-2 is a novel coronavirus, not encountered before by humans. The wide spectrum of clinical expression of SARS-CoV-2 illness suggests that individual immune responses to SARS-CoV-2 play a crucial role in determining the clinical course after first infection. Immunological studies have focused on patients with moderate to severe disease, demonstrating excessive inflammation in tissues and organ damage. In order to understand the basis of the protective immune response in COVID-19, we performed a longitudinal follow-up, flow-cytometric and serological analysis of innate and adaptive immunity in 64 adults with a spectrum of clinical presentations: 28 healthy SARS-CoV-2-negative contacts of COVID-19 cases; 20 asymptomatic SARS-CoV-2-infected cases; eight patients with Mild COVID-19 disease and eight cases of Severe COVID-19 disease. Our data show that high frequency of NK cells and early and transient increase of specific IgA, IgM and, to a lower extent, IgG are associated with asymptomatic SARS-CoV-2 infection. By contrast, monocyte expansion and high and persistent levels of IgA and IgG, produced relatively late in the course of the infection, characterize severe disease. Modest increase of monocytes and different kinetics of antibodies are detected in mild COVID-19. The importance of innate NK cells and the short-lived antibody response of asymptomatic individuals and patients with mild disease suggest that only severe COVID-19 may result in protective memory established by the adaptive immune response
An Ultraconserved Element Containing lncRNA Preserves Transcriptional Dynamics and Maintains ESC Self-Renewal
Ultraconserved elements (UCEs) show the peculiar feature to retain extended perfect sequence identity among human, mouse, and rat genomes. Most of them are transcribed and represent a new family of long non-coding RNAs (lncRNAs), the transcribed UCEs (T-UCEs). Despite their involvement in human cancer, the physiological role of T-UCEs is still unknown. Here, we identify a lncRNA containing the uc.170+, named T-UCstem1, and provide in vitro and in vivo evidence that it plays essential roles in embryonic stem cells (ESCs) by modulating cytoplasmic miRNA levels and preserving transcriptional dynamics. Specifically, while T-UCstem1::miR-9 cytoplasmic interplay regulates ESC proliferation by reducing miR-9 levels, nuclear T-UCstem1 maintains ESC self-renewal and transcriptional identity by stabilizing polycomb repressive complex 2 on bivalent domains. Altogether, our findings provide unprecedented evidence that T-UCEs regulate physiological cellular functions and point to an essential role of T-UCstem1 in preserving ESC identity
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