21 research outputs found

    Unraveling maternal and fetal genetic factors protecting from Pregnancy Associated Malaria in the mouse

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    Malaria is one of the most devastating diseases in the world. In Plasmodium endemic regions, pregnant women are among the most vulnerable groups. Pregnancy Associated Malaria (PAM) threatens both maternal and foetal lives. Despite differences between human and mouse placentas PAM mouse models recapitulate key pathological features of human PAM. Here we describe new PAM models of mid gestation infection in the C57BL/6 mouse.(...

    Avaliação da presença na Internet das câmaras municipais portuguesas em 2003: relatório final

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    O presente estudo tem como objectivo aferir a maturidade da presença na Internet das câmaras municipais e foi realizado durante o terceiro trimestre de 2003. Para a concretização do objectivo referido, procedeu-se à análise dos serviços disponibilizados na Internet pelas câmaras municipais portuguesas, através da observação online dos seus web sites. Para a avaliação da natureza dos serviços disponibilizados, da sua funcionalidade e dos níveis de interactividade permitidos, foram adaptados os critérios de análise propostos na metodologia de avaliação dos web sites dos organismos da administração directa e indirecta do Estado. Os critérios estabelecidos para a avaliação foram os seguintes: conteúdos; actualização dos conteúdos; acessibilidade; navegabilidade; facilidades para cidadãos com necessidades especiais; utilização do correio electrónico. Foram valorizados os aspectos relacionados com a disponibilização de serviços online aos cidadãos e às empresas. Avaliação do nível de maturidade da presença na Internet das câmaras municipais, centrada na aferição da qualidade dos serviços online oferecidos pelas autarquias aos cidadãos e às empresas.Agência para a Sociedade do Conhecimento (UMIC

    HGF Secreted by Activated Kupffer Cells Induces Apoptosis of Plasmodium-Infected Hepatocytes

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    This deposit is composed by the main article plus the supplementary materials of the publicationMalaria liver stage infection is an obligatory parasite development step and represents a population bottleneck in Plasmodium infections, providing an advantageous target for blocking parasite cycle progression. Parasite development inside hepatocytes implies a gross cellular insult evoking innate host responses to counteract intra-hepatocytic infection. Using primary hepatocyte cultures, we investigated the role of Kupffer cell-derived hepatocyte growth factor (HGF) in malaria liver stage infection. We found that Kupffer cells from Plasmodium-infected livers produced high levels of HGF, which trigger apoptosis of infected hepatocytes through a mitochondrial-independent apoptosis pathway. HGF action in infected hepatocyte primary cultures results in a potent reduction of parasite yield by specifically sensitizing hepatocytes carrying established parasite exo-erythrocytic forms to undergo apoptosis. This apoptosis mechanism is distinct from cell death that is spontaneously induced in infected cultures and is governed by Fas signaling modulation through a mitochondrial-dependent apoptosis pathway. This work indicates that HGF and Fas signaling pathways are part of an orchestrated host apoptosis response that occurs during malaria liver stage infection, decreasing the success of infection of individual hepatocytes. Our results raise the hypothesis that paracrine signals derived from Kupffer cell activation are implicated in directing death of hepatocytes infected with the malaria parasite.info:eu-repo/semantics/publishedVersio

    Preclinical development of a bispecific TNFα/IL-23 neutralising domain antibody as a novel oral treatment for inflammatory bowel disease.

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    Anti-TNFα and anti-IL-23 antibodies are highly effective therapies for Crohn's disease or ulcerative colitis in a proportion of patients. V56B2 is a novel bispecific domain antibody in which a llama-derived IL-23p19-specific domain antibody, humanised and engineered for intestinal protease resistance, V900, was combined with a previously-described TNFα-specific domain antibody, V565. V56B2 contains a central protease-labile linker to create a single molecule for oral administration. Incubation of V56B2 with trypsin or human faecal supernatant resulted in a complete separation of the V565 and V900 monomers without loss of neutralising potency. Following oral administration of V900 and V565 in mice, high levels of each domain antibody were detected in the faeces, demonstrating stability in the intestinal milieu. In ex vivo cultures of colonic biopsies from IBD patients, treatment with V565 or V900 inhibited tissue phosphoprotein levels and with a combination of the two, inhibition was even greater. These results support further development of V56B2 as an oral therapy for IBD with improved safety and efficacy in a greater proportion of patients as well as greater convenience for patients compared with traditional monoclonal antibody therapies

    Distinct placental malaria pathology caused by different Plasmodium berghei lines that fail to induce cerebral malaria in the C57BL/6 mouse

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    Background: Placental malaria (PM) is one major feature of malaria during pregnancy. A murine model of experimental PM using BALB/c mice infected with Plasmodium berghei ANKA was recently established, but there is need for additional PM models with different parasite/host combinations that allow to interrogate the involvement of specific host genetic factors in the placental inflammatory response to Plasmodium infection. Methods: A mid-term infection protocol was used to test PM induction by three P. berghei parasite lines, derived from the K173, NK65 and ANKA strains of P. berghei that fail to induce experimental cerebral malaria (ECM) in the susceptible C57BL/6 mice. Parasitaemia course, pregnancy outcome and placenta pathology induced by the three parasite lines were compared. Results: The three P. berghei lines were able to evoke severe PM pathology and poor pregnancy outcome features. The results indicate that parasite components required to induce PM are distinct from ECM. Nevertheless, infection with parasites of the ANKA Delta pm4 line, which lack expression of plasmepsin 4, displayed milder disease phenotypes associated with a strong innate immune response as compared to infections with NK65 and K173 parasites. Conclusions: Infection of pregnant C57BL/6 females with K173, NK65 and ANKA Delta pm4 P. berghei parasites provide experimental systems to identify host molecular components involved in PM pathogenesis mechanisms.Fundacao de Ciencia e Tecnologia (FCT), PortugalFundacao de Ciencia e Tecnologia (FCT), PortugalFCTFC

    Distinct placental malaria pathology caused by different Plasmodium berghei lines that fail to induce cerebral malaria in the C57BL/6 mouse

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    Abstract\ud \ud Background\ud Placental malaria (PM) is one major feature of malaria during pregnancy. A murine model of experimental PM using BALB/c mice infected with Plasmodium berghei ANKA was recently established, but there is need for additional PM models with different parasite/host combinations that allow to interrogate the involvement of specific host genetic factors in the placental inflammatory response to Plasmodium infection.\ud \ud \ud Methods\ud A mid-term infection protocol was used to test PM induction by three P. berghei parasite lines, derived from the K173, NK65 and ANKA strains of P. berghei that fail to induce experimental cerebral malaria (ECM) in the susceptible C57BL/6 mice. Parasitaemia course, pregnancy outcome and placenta pathology induced by the three parasite lines were compared.\ud \ud \ud Results\ud The three P. berghei lines were able to evoke severe PM pathology and poor pregnancy outcome features. The results indicate that parasite components required to induce PM are distinct from ECM. Nevertheless, infection with parasites of the ANKAΔpm4 line, which lack expression of plasmepsin 4, displayed milder disease phenotypes associated with a strong innate immune response as compared to infections with NK65 and K173 parasites.\ud \ud \ud Conclusions\ud Infection of pregnant C57BL/6 females with K173, NK65 and ANKAΔpm4 P. berghei parasites provide experimental systems to identify host molecular components involved in PM pathogenesis mechanisms

    In memoriam: José Marques (1937-2021), Maria Filomena Barros (1958-2021), Helena Avelar (1964-2021)

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    Houve demasiadas mortes em dias assim. No último ano, em dois números sucessivos da Medievalista, demos notícia do desaparecimento de três historiadores europeus: Francis Rapp e Michel Parisse, em Julho de 2020, Peter Linehan, já em Janeiro deste ano, todos com obra notável e que marcaram, por razões diversas, diferentes gerações de investigadores. As perdas, infelizmente, não ficaram por aí. Nos últimos meses, a lista de falecimentos parecia não ter fim, levando historiadores em diferentes fases das suas vidas, uns mais conhecidos e consagrados, outros em plena maturidade intelectual. Dia após dia, como se em todos fosse preciso recordar que o historiador morreu, desapareceram muitos dos que dedicaram a vida a esclarecer os assuntos do passado. Nomes em demasia, como os de Francesco Espósito, de Luís Espinha da Silveira, deAntónio Silva Pereira, deJosé Marques, de Maria Filomena Barros, de Francisco Contente Domingues e de Helena Avelar, ou de Pierre Guichard e de Pedro Laíns, estes dois já bem mais perto de nós

    Using distinct molecular signatures of human monocytes and dendritic cells to predict adjuvant activity and pyrogenicity of TLR agonists

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    We present a systematic study that defines molecular profiles of adjuvanticity and pyrogenicity induced by agonists of human Toll-like receptor molecules in vitro. Using P3CSK4, Lipid A and Poly I:C as model adjuvants we show that all three molecules enhance the expansion of IFNγ+/CD4+ T cells from their naïve precursors following priming with allogeneic DC in vitro. In contrast, co-culture of naive CD4+ T cells with allogeneic monocytes and TLR2/TLR4 agonists only resulted in enhanced T cell proliferation. Distinct APC molecular signatures in response to each TLR agonist underline the dual effect observed on T cell responses. Using protein and gene expression assays, we show that TNF-α and CXCL10 represent DC-restricted molecular signatures of TLR2/TLR4 and TLR3 activation, respectively, in sharp contrast to IL-6 produced by monocytes upon stimulation with P3CSK4 and Lipid A. Furthermore, although all TLR agonists are able to up-regulate proIL-1β specific gene in both cell types, only monocyte activation with Lipid A results in detectable IL-1β release. These molecular profiles, provide a simple screen to select new immune enhancers of human Th1 responses suitable for clinical application

    A complex scenario of tuberculosis transmission is revealed through genetic and epidemiological surveys in Porto

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    Tuberculosis (TB) incidence is decreasing worldwide and eradication is becoming plausible. In low-incidence countries, intervention on migrant populations is considered one of the most important strategies for elimination. However, such measures are inappropriate in European areas where TB is largely endemic, such as Porto in Portugal. We aim to understand transmission chains in Porto through a genetic characterization of Mycobacterium tuberculosis strains and through a detailed epidemiological evaluation of cases.This work was developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER), and supported by contributions from Iceland, Liechtenstein and Norway through the European Economic Area Grants under the Public Health Initiative programme, (PT06, Project 000138DT1). TR is supported by the Portuguese Foundation for Science and Technology (FCT) through a post-doctoral grant (SFRH/BPD/108126/2015)info:eu-repo/semantics/publishedVersio

    Influenza severe cases in hospitals, between 2014 and 2016 in Portugal

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    Rede Portuguesa de Laboratórios para o Diagnóstico da GripeBackground: Since 2009, the Portuguese Laboratory Network (PLNID) for Influenza Diagnosis has integrated 15 Laboratories in mainland and Atlantic Islands of Azores and Madeira. This PLNID added an important contribute to the National Influenza Surveillance Program regarding severe and hospitalized influenza cases. The present study aims to describe influenza viruses detected in influenza like illness (ILI) cases: outpatients (Outp), hospitalized (Hosp), and intensive care units (ICU), between 2014 and 2016. Methods: The PLNID performs influenza virus diagnosis by biomolecular methodologies. Weekly reports to the National Influenza Reference Laboratory ILI cases tested for influenza. Reports include data on detecting viruses, hospital assistance, antiviral therapeutics, and information on death outcome. Were reported during two winter seasons 8059 ILI cases,being 3560 cases in 2014/15 (1024 in Outp, 1750 Hosp, and 606 in ICU) and 4499 cases in 2015/2016 (1933 in Outp, 1826 Hosp, and 740 in ICU). Results: The higher percentage of influenza positive cases were detected in Outp in both seasons, 18% during 2014/15 and 20% in 2015/16. In 2014/15,influenza cases were more frequent in individuals older than 65 years old and these required more hospitalizations,even in ICU. In 2015/16,the influenza cases were mainly detected in individuals between 15-64 years old. A higher proportion of influenza positive cases with hospitalization in ICU were observed in adults between 45-64 years old.During the study period,the predominant circulating influenza viruses were different in the two seasons: influenza B and A(H3) co-circulated in 2014/15,and influenza A(H1)pdm09 was predominant during 2015/16. Even when influenza A is notthe dominant virus, A(H3) and A(H1)pdm09 subtypes correlate with higher detection rate in hospitalized cases (Hosp and UCI), with higher frequencies in adults older than 45. Influenza B,detected in higher proportion in outpatients, was frequently relatedwith influenza cases in younger age groups: 0-4 and 5-14 years old. Conclusions: This study highlights the correlation of theinfluenza virus type/subtype that circulates in each season with the possible need for hospitalization and intensive care in special groups of the population. Circulation of influenza A subtypes can cause more frequentdisease in individuals older than 45, with need of hospitalization including intensive care. On the other hand, influenza B is more frequently associated with less severe cases and with infection in children and younger adults. Influenza B circulation might predict lower number of hospitalizations.The identification of influenza type in circulation,byPLNID ineach season, could guide action planning measures in population health care.info:eu-repo/semantics/publishedVersio
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