Tail-anchored proteins at peroxisomes: identification of MIRO1 as a novel peroxisomal motility factor

Peroxisomes are dynamic and multifunctional organelles, which are essential for human health and development. They are remarkably diverse, with functions that vary significantly between cells and organisms, and can dramatically change their size, shape and dynamics in response to cellular cues. In the past few years, several studies have significantly increased our understanding of the basic principles that enable peroxisome biogenesis and degradation, as well as their pivotal role in cellular signalling and homeostasis. However, several of these processes are still poorly understood. In this thesis we initially studied the peroxisome targeting mechanism of a group of C-terminally anchored membrane proteins, known as tail-anchored (TA) proteins. In order to investigate the molecular signals that enable TA protein targeting to cellular organelles, we analysed the physicochemical properties of a cohort of TA proteins both in silico and in vivo, and show that a combination of transmembrane domain (TMD) hydrophobicity and C-terminal tail charge determines organelle-specific targeting. Focusing on peroxisomes, we demonstrate that a balance between TMD hydrophobicity and high positive tail charge directs TA proteins to this organelle, and enables binding to the peroxisomal chaperone PEX19. These results allowed us to create a bioinformatical tool to predict the targeting of uncharacterised TA proteins and further develop our understanding of the molecular mechanisms involved in the targeting of this protein group. From our initial TA protein screen, we identified the TA protein MIRO1 at peroxisomes and looked at its role in the regulation of peroxisome motility. We show that endogenous MIRO1 localises to mitochondria and peroxisomes, and that dual targeting depends on the C-terminal tail. MIRO1 expression significantly increased peroxisome motility in several cell lines, and revealed a role for motility in peroxisome dynamics, by inducing organelle proliferation and elongation. These results reveal a new molecular complex at peroxisomes and provide us with a tool to further dissect the role of motility on peroxisome function.University of Exete

The model of local axon homeostasis - Explaining the role and regulation of microtubule bundles in axon maintenance and pathology

Axons are the slender, cable-like, up to meter-long projections of neurons that electrically wire our brains and bodies. In spite of their challenging morphology, they usually need to be maintained for an organism's lifetime. This makes them key lesion sites in pathological processes of ageing, injury and neurodegeneration. The morphology and physiology of axons crucially depends on the parallel bundles of microtubules (MTs), running all along to serve as their structural backbones and highways for life-sustaining cargo transport and organelle dynamics. Understanding how these bundles are formed and then maintained will provide important explanations for axon biology and pathology. Currently, much is known about MTs and the proteins that bind and regulate them, but very little about how these factors functionally integrate to regulate axon biology. As an attempt to bridge between molecular mechanisms and their cellular relevance, we explain here the model of local axon homeostasis, based on our own experiments in Drosophila and published data primarily from vertebrates/mammals as well as C. elegans. The model proposes that (1) the physical forces imposed by motor protein-driven transport and dynamics in the confined axonal space, are a life-sustaining necessity, but pose a strong bias for MT bundles to become disorganised. (2) To counterbalance this risk, MT-binding and -regulating proteins of different classes work together to maintain and protect MT bundles as necessary transport highways. Loss of balance between these two fundamental processes can explain the development of axonopathies, in particular those linking to MT-regulating proteins, motors and transport defects. With this perspective in mind, we hope that more researchers incorporate MTs into their work, thus enhancing our chances of deciphering the complex regulatory networks that underpin axon biology and pathology

Production Of Vegetable Oil Blends And Structured Lipids And Their Effect On Wound Healing

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Two oil blends (sunflower/canola oils 85/15 (BL1) and canola/linseed oils 70/30 (BL2)), were prepared and enzymatically interesterified to be applied to surgically-induced wounds in rats. Following surgery, the animals were submitted to the Treatment with Physiological Saline (TPS) (control group), Blends (TBL), and Structured Lipids (TSL). The control group (TPS) received physiological saline solution for 15 days. In TBL, BL1 was administered during the inflammation phase (days 0-3) and BL2 in the tissue formation and remodeling phase (days 4-15). In TSL, Structured Lipid 1 (SL1) and Structured Lipid 2 (SL2) were used instead of BL1 and BL2, respectively. The aim of this study was to compare wound closure evolution among rats treated with the blends or structured lipids versus control rats treated with physiological saline. The wound healing process was evaluated by measuring the wound areas along the treatments and the concentrations of cytokines. An increase in the areas of wounds treated with the blends and structured lipids in the inflammatory phase was observed, followed by a steeper closure curve compared to wounds treated with physiological saline. The changes observed during the inflammatory phase suggest a potential therapeutic application in cutaneous wound healing which should be further investigated.512415427Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Methodology for rhetorical analysis in urban project contests : a case study in an architecture collection of competition entries: from 2006 to 2016

A pesquisa que originou este artigo investigou a retórica verbal e visual como metodologia de análise de projetos urbanos em concursos a partir de uma amostra selecionada no Acervo de Arquitetura de Concursos da Universidade Federal do Rio Grande do Sul. Como metodologia de pesquisa, foram construídas ferramentas, a partir de softwares de análise verbal e gráfica, para identificar aspectos verbais (textos) e visuais (desenhos) e caracterizar padrões retóricos dos projetos de concursos. O resultado foi a detecção das abordagens mais utilizadas nos documentos oficiais dos concursos e nas apresentações dos trabalhos, o que permitiu comparar esquemas retóricos presentes nos projetos preferidos pelos jurados. Além disso, o resultado também apontou aspectos retóricos frequentemente replicados por organizadores em documentos oficiais e pelas equipes participantes nos trabalhos apresentados. A pesquisa foi relevante não só por ampliar o conhecimento sobre os acervos de projeto, mas também por dar luz aos padrões retóricos utilizados em concursos. Esse conhecimento prévio pode incrementar a qualidade de documentos e projetos em concursos futuros.The research that originated this article investigated verbal and visual rhetoric as a methodology for analyzing urban projects in competition entries in a sample selected from the Universidade Federal do Rio Grande do Sul Architecture Collection of Competition Entries. As a research methodology, tools were built from verbal and graphical analysis software to identify the verbal (text) and visual (drawings) aspects characterizing rhetorical patterns of contest entries. The result was the detection of the most commonly used approaches in the official documents and presentations. This allowed the researchers to compare the rhetorical schemes present in the projects with the preference of the judges. It also pointed out rhetorical aspects often replicated by organizers in official documents and by the teams participating in the papers presented. The research was relevant not only for broadening the knowledge about the collection of projects, but also for shedding light on the rhetorical patterns used in competitions. This prior knowledge can increase the quality of documents and projects in future competitions

Technical assistance in social housing for the promotion of healthy habitat

A precariedade das condições de moradia no Brasil tem sérias implicações sobre o habitat saudável. No ano de 2020, o advento da pandemia de Covid-19 acrescentou urgência às discussões acerca da habitação saudável, principalmente nas periferias das cidades; onde se encontram as maiores carências: de habitabilidade, de fornecimento de água, de infraestrutura e saneamento básico. Nesse contexto, a aplicação da Lei 11.888 de 2008, da Assistência Técnica em Habitação de Interesse Social (ATHIS), tem oportunizado o acesso ao trabalho dos profissionais de arquitetura para a população de baixa renda. Além disso, as iniciativas de ATHIS têm buscado a consolidação de projetos de habitação de interesse social que resultem na produção de unidades habitacionais mais saudáveis. O presente artigo apresenta um estudo de caso sobre o processo de desenvolvimento da ATHIS para uma comunidade de 68 famílias da cidade de São Leopoldo, Região Metropolitana de Porto Alegre, estado do Rio Grande do Sul. O objetivo deste estudo é compreender como o processo de ATHIS pôde contribuir para a promoção do habitat saudável naquela comunidade. As técnicas de coleta de dados utilizadas foram: análise de documentos, observação assistemática não-participante e entrevistas semiestruturadas. Os resultados permitiram constatar que: i) a ATHIS envolvendo a população através de processo participativo, apresenta contribuições para a melhoria das condições de habitabilidade das populações envolvidas; ii) a ATHIS pode contribuir para a consolidação de um habitat saudável através da melhoria da qualidade do ambiente urbano e habitacional, destacando-se as condições básicas de saneamento.The precariousness of housing conditions in Brazil has serious implications for healthy habitat. In the year 2020, the advent of the Covid-19 pandemic, added urgency to the discussions about healthy housing, especially on the outskirts of cities; where the greatest needs are found: habitability, water supply, infrastructure and basic sanitation. In this context, the application of Law 11,888 of 2008, of Technical Assistance in Social Housing (ATHIS), has provided opportunities for the work of architecture professionals for the low-income population. In addition, ATHIS initiatives have sought to consolidate social housing projects that result in the production of healthier housing units. This article presents a case study on the ATHIS development process for a community of 68 families in the city of São Leopoldo, Metropolitan Region of Porto Alegre, state of Rio Grande do Sul. The objective of this study was to understand how ATHIS process can contribute to the promotion of healthy habitat for low-income populations. The data collection techniques used were: document analysis, non-participant unsystematic observation and semi-structured interviews. The results showed that: i) ATHIS involving the population through a participatory process, contributes to the improvement of the habitability conditions of the populations involved; ii) ATHIS can contribute to the consolidation of a healthy habitat by improving the quality of the urban and housing environment, with emphasis on basic sanitation conditions

Preparation of modified clay with cetylpyridinium chloride and evaluation of their interaction with PVC

Foi preparada uma argila modificada com cloreto de cetilpiridíneo a partir da argila sódica por troca de cátions em solução. Foi avaliada a quantidade de agente de modificação em relação à argila sódica e o tempo reacional. Os materiais obtidos foram caracterizados por difração de raio X (XRD), análise termogravimétrica (TGA) e ressonância magnética nuclear (RMN) de baixo campo. Após a caracterização foi confirmada a modificação da argila e, também, foi verificado que o produto obtido pode ser empregado na preparação de nanocompósitos de PVC, considerando que o início da degradação do material preparado ocorreu em temperatura superior às comumente utilizadas no processamento do polímero. A adição da argila modificada apresentou uma dispersão adequada no PVC e manteve o início da degradação do material em temperatura compatível com o processamento do polímero, gerando um nanocompósito com parte esfoliada e intercalada. _________________________________________________________________________________ ABSTRACTA modified silicate with cetylpyridinium was prepared from sodium clay with cation exchange in solution. The amount of modification agent for clay and the reaction time were evaluated. The materials produced were characterized using X ray diffraction (XRD), termogravimetric analysis (TGA) and low field nuclear magnetic resonance (NMR). The formation of new organic clay was confirmed, which was introduced in PVC for the formation of nanocomposites. The beginning of degradation of the new clay occurred at temperatures higher than commonly used in the processing of PVC. The nanocomposites were partially exfoliated and partially intercalated

Prandial correlations and structure of the ingestive behavior of pigs in precision feeding programs

The feeding behavior of growing-finishing pigs was analyzed to study prandial correlations and the probability of starting a new feeding event. The data were collected in real-time based on 157,632 visits by a group of 70 growing-finishing pigs (from 30.4 to 115.5 kg body weight, BW) to automatic feeders. The data were collected over 84 days, during which period the pigs were kept in conventional (by phase and by group) or precision (with daily and individual adjustments) feeding programs. A criterion to delimit each meal was then defined based on the probability of an animal starting a new feeding event within the next minute since the last visit. Prandial correlations were established between meal size and interval before meal (pre-prandial) or interval after meal (postprandial) using Pearson correlation analysis. Post-prandial correlations (which can be interpreted as hunger-regulating mechanisms) were slightly stronger than pre-prandial correlations (which can be interpreted as satiety regulation mechanisms). Both correlations decreased as the animals’ age increased but were little influenced by the feeding programs. The information generated in this study allows a better understanding of pigs’ feeding behavior regulation mechanisms and could be used in the future to improve precision feeding programs

Continuous Improvement Cells in the Highways Sector

In line with its performance improvement and Lean Construction agenda, the highways supply chain in the UK has commenced many Continuous Improvement (CI) cells in recent years. The CI cell is a small-group work coordination and improvement technique that is frequently used in many industries as part of their lean transformations. The technique has also its links to some key lean concepts and practices like continuous improvement (kaizen), Visual Management and hoshinkanri policy deployment. This paper presents a summary of a detailed research aiming to understand the execution of the CI cells in the highways supply chain in the UK with their associated benefits and challenges through a study of 12 CI cells at the main client organisation. Alongside a set of benefits and challenges, the current CI cell execution mechanism and some suggestions to improve the current practice were also presented in the paper