Towards systematic identification of Plasmodium essential genes by transposon shuttle mutagenesis

After the deciphering of the genome sequences of several Plasmodium species, efforts must turn to elucidating gene function and identifying essential gene products. However, random approaches are lacking and gene targeting is inefficient in Plasmodium. Here, we established shuttle transposon mutagenesis in Plasmodium berghei. We constructed a mini-Tn5 derivative that can transpose into parasite genes cloned in Escherichia coli, providing an efficient means of generating knockout fragments. A 10(4)-fold increase in frequencies of double-crossover homologous recombination in the parasite using a new electroporation technology permits to reproducibly generate pools of distinct mutants after transfection with mini-Tn5-interrupted sequences. The procedure opens the way to the systematic identification of essential genes in Plasmodium

Compromisso com a responsabilidade social em Portugal: um estudo comparativo entre as áreas metropolitanas de Lisboa e do Porto

Trabalho apresentado em III International Forum on Management, 1-2 fevereiro 2019, Évora, PortugalN/

Compromiso con la responsabilidad social en Portugal: estudio comparativo entre las áreas metropolitanas de Lisboa y Oporto

Social Responsibility has become a key piece for organizations. At the same time that society is increasingly demanding access to information, this becomes particularly important in the case of public organisations. The use of Information and Communication Technologies (ICT) is an easy and effective way for a large part of the population to access information. Organisations should therefore use this channel of communication to inform and communicate with their audience. This work aims to establish a comparison between the metropolitan areas of Lisbon and Porto of the degree of dissemination of information on Social Responsibility made by local public administrations through their webpages. To this end, a content analysis was carried out applying indicators previously tested in other territories. The results suggest that, in general, local public administrations in the two metropolitan areas are developing specific Social Responsibility policies showing the same commitment to sustainability, although the Lisbon metropolitan area seems to be more committed to environmental information.La Responsabilidad Social se ha convertido en una pieza clave para las organizaciones. Al mismo tiempo que la sociedad exige cada vez más el acceso a la información, esto se vuelve particularmente importante en el caso de las organizaciones públicas. El uso de las tecnologías de la información y las comunicaciones (TIC) es una forma fácil y eficaz de acceder a la información para una gran parte de la población. Por lo tanto, las organizaciones deben utilizar este canal de comunicación para informar y comunicarse con su público. Este trabajo tiene por objeto establecer una comparación entre las áreas metropolitanas de Lisboa y Oporto del grado de divulgación de la información sobre Responsabilidad Social que realizan las administraciones públicas locales a través de sus portales web. Con ese fin, se realizó un análisis de contenido aplicando indicadores previamente probados en otros territorios. Los resultados sugieren que, en general, las administraciones públicas locales de las dos áreas metropolitanas están elaborando políticas específicas de Responsabilidad Social que muestran el mismo compromiso con la sostenibilidad, aunque el área metropolitana de Lisboa parece estar más comprometida con la información ambiental

Standardised inventories of spiders (Arachnida, Araneae) on touristic trails of the native forests of the Azores (Portugal)

Background The sharp increase in tourist visitation of the Azores Archipelago from 2015 onwards raised concerns about the impacts of recreational tourism on native habitats. In response, a project was financed by the Azorean Government to investigate the drivers of biodiversity erosion associated with recreational tourism. Here, we present the data on spider biodiversity found on trails located within the native Azorean forests as they are home to several endemic species of great conservation value. We applied an optimised and standardised sampling protocol (COBRA) in twenty-three plots located in five trails on Terceira and Sao Miguel Islands and assessed diversity and abundance of spider species at different distances from the trail head and the trail itself. New information Of the 45 species (12435 specimens) collected, 13 were endemic to the Azores (9690 specimens), 10 native non-endemic (2047 specimens) and 22 introduced (698 specimens). This database will be the baseline of a long-term monitoring project for the assessment of touristic impacts on native forest trails. This methodology can also be used on other habitats and biogeograhical regions.Peer reviewe

An atypical cyclin-dependent kinase controls Plasmodium falciparum proliferation rate

Malaria parasites multiply in human erythrocytes through schizogony, a process characterised by nuclear divisions in the absence of cytokinesis, leading to the formation of a multinucleated schizont from which individual daughter cells are subsequently generated. Here, we provide evidence that parasites lines lacking Pfcrk-5, an atypical cyclin-dependent kinase, display a reduced parasitemia growth rate linked to a decrease in the number of daughter nuclei produced by each schizont. We show that in vitro activity of recombinant Pfcrk-5 is indeed cyclin-dependent and that the enzyme localises to the nuclear periphery. Thus, Pfcrk-5 is part of a regulatory pathway that mediates the proliferation rate of Plasmodium falciparum through the control of nuclear divisions during schizogony

Abstracts

Tradução, para a língua Inglesa, dos resumos dos artigos publicados nesta edição

Mycobacterium tuberculosis associated with severe tuberculosis evades cytosolic surveillance systems and modulates IL-1β production

Genetic diversity of Mycobacterium tuberculosis affects immune responses and clinical outcomes of tuberculosis (TB). However, how bacterial diversity orchestrates immune responses to direct distinct TB severities is unknown. Here we study 681 patients with pulmonary TB and show that M. tuberculosis isolates from cases with mild disease consistently induce robust cytokine responses in macrophages across multiple donors. By contrast, bacteria from patients with severe TB do not do so. Secretion of IL-1β is a good surrogate of the differences observed, and thus to classify strains as probable drivers of different TB severities. Furthermore, we demonstrate that M. tuberculosis isolates that induce low levels of IL-1β production can evade macrophage cytosolic surveillance systems, including cGAS and the inflammasome. Isolates exhibiting this evasion strategy carry candidate mutations, generating sigA recognition boxes or affecting components of the ESX-1 secretion system. Therefore, we provide evidence that M. tuberculosis strains manipulate host-pathogen interactions to drive variable TB severities

A prediction rule to stratify mortality risk of patients with pulmonary tuberculosis

Tuberculosis imposes high human and economic tolls, including in Europe. This study was conducted to develop a severity assessment tool for stratifying mortality risk in pulmonary tuberculosis (PTB) patients. A derivation cohort of 681 PTB cases was retrospectively reviewed to generate a model based on multiple logistic regression analysis of prognostic variables with 6-month mortality as the outcome measure. A clinical scoring system was developed and tested against a validation cohort of 103 patients. Five risk features were selected for the prediction model: hypoxemic respiratory failure (OR 4.7, 95% CI 2.8-7.9), age >= 50 years (OR 2.9, 95% CI 1.7-4.8), bilateral lung involvement (OR 2.5, 95% CI 1.44.4), >= 1 significant comorbidity-HIV infection, diabetes mellitus, liver failure or cirrhosis, congestive heart failure and chronic respiratory disease-(OR 2.3, 95% CI 1.3-3.8), and hemoglobin = 6) mortality risk. The mortality associated with each group was 2.9%, 22.9% and 53.9%, respectively. The model performed equally well in the validation cohort. We provide a new, easy-to-use clinical scoring system to identify PTB patients with high-mortality risk in settings with good healthcare access, helping clinicians to decide which patients are in need of closer medical care during treatment.This work was supported by Fundacao Amelia de Mello/Jose de Mello Saude and Sociedade Portuguesa de Pneumologia (SPP). 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). NSO is a FCT (Fundacao para a Ciencia e Tecnologia) investigator. MS is an Associate FCT Investigator. The fundershad no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Identificação de Problemas e Propostas para Melhoria

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