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Resumo: Este estudo teve como objetivo descrever um inquérito quantitativo realizado com lideranças para investigar ações efetivas, viáveis e que podem ser testadas em modelos computacionais para informar políticas de promoção da mobilidade ativa, tendo como base a cidade de São Paulo, Brasil. Em 2022, foi realizado um inquérito online no contexto da pesquisa de Atividade Física e Ambiente do Inquérito de Saúde de São Paulo, acompanhada por representantes de organizações não governamentais, gestores públicos e de entidades privadas. Foi elaborado questionário com três perguntas com 13 alternativas de respostas sobre ações para promoção da caminhada ou uso de bicicleta. As lideranças deveriam selecionar até três alternativas a partir de seu potencial em termos de (1) efetividade; (2) viabilidade ou facilidade de implementação; e (3) desejo de realizar testes em modelos computacionais para informar políticas. O inquérito foi respondido por 18 lideranças de 16 instituições, sendo 13 (72%) mulheres e 12 (67%) representantes do terceiro setor, cuja média de idade era 48 anos, todos com nível superior de escolaridade. A redução da velocidade dos veículos motorizados foi a opção mais citada nas três questões. Outras ações citadas referem-se ao controle de circulação de veículos em regiões centrais, à segurança de pedestres, à diminuição das distâncias entre residências e locais de emprego, às campanhas educativas e à ampliação e melhoria de estruturas como ciclovias e calçadas. Os resultados são relevantes para apoiar a tomada de decisões baseadas em evidências na gestão pública e oferecer subsídios para a elaboração de modelos computacionais com vistas à promoção da mobilidade ativa.

A pesquisa realizada em arquivos e acervos literários de escritores pode nos revelar poemas desconhecidos da antologia tradicional, o processo de criação de algumas obras, ou até revelar facetas até então desconhecidas desses artistas. É o que ocorre quando se pesquisa no acervo da escritora Hilda Hilst no CEDAE – Centro de Documentação Alexandre Eulálio –, na Unicamp. Nele encontramos a face de uma Hilda Hilst estreando no círculo literário paulistano de 1949. Desse modo, este artigo busca trazer ao público parte da pesquisa que documentou dois poemas de Hilda Hilst publicados em periódicos literários de 1949 e que não aparecem nas anto­logias tradicionais de Hilda Hilst até 2017. Aqui, trataremos do conjunto publicado na Colégio Revista de Cultura e Arte (1948-1949).

The aim of this study is to explore the relationship between individual-level factors and cycling for transportation in a cohort of participants living in São Paulo city, Brazil. The same participants (n = 1,431 adults) were interviewed in 2014/2015 (Wave 1) and 2020/2021 (Wave 2) as part of the ‘São Paulo Health Survey-ISA: Physical Activity and Environment’. For the longitudinal transport cycling binary outcome, participants who reported cycling at both time-points and those who were cycling at Wave 2 only were coded as a positive longitudinal pattern for cycling. Those who were not cycling at either Waves, and those who were cycling at Wave 1 only, were grouped into a negative pattern for cycling. The relationship between the longitudinal patterns for transport cycling and sociodemographics, health characteristics, and behaviors at Wave 1 were tested using bivariate analysis, and the significant individual-level factors were then examined in a multivariable binary logistic regression model. The odds of being classified in the positive cycling pattern were lower for women [OR = 0.09; 95 % CI = 0.04–––0.19], and higher for persons aged 30 – 39 [OR = 3.25; 95 % CI = 1.38–––7.66], those who owned a bicycle [OR = 2.00; 95 % CI = 1.13–––3.54], and those who engaged in ≥ 120 min/week of transport walking [OR = 2.07; 95 % CI = 1.24–––3.47] or leisure-time physical activity [OR = 1.77; 95 % CI = 1.02–––3.06]. Cycling interventions and promotion should target women, the mid-aged and involve facilitating bicycle access. Advocacy for physical activity interventions is needed to influence transport cycling.

Objetivo. Sintetizar os achados sobre correlatos da atividade física (AF) e do comportamento sedentário (CS) em crianças sul-americanas. Método. Realizou-se uma busca dos artigos no período de 24 de junho até 27 de outubro de 2020, nas bases de dados LILACS, PubMed, SciELO, Scopus e Web of Science. Para ampliar a busca, foram examinadas as referências dos artigos de revisão identificados e realizada uma consulta a um painel de especialistas. Foram incluídos estudos com delineamentos observacional e de intervenção com foco em crianças sul-americanas de zero a 5 anos de idade. Resultados. Dos 3 111 artigos inicialmente identificados, 18 foram elegíveis: 14 com delineamento observacional, 12 realizados no Brasil e 17 conduzidos com pré-escolares (3 a 5 anos de idade). Além do Brasil, os únicos países representados foram o Chile e o Equador. A AF e o CS foram medidos por acelerômetros em sete estudos, porém houve alta variabilidade nos instrumentos e pontos de corte usados. Embora as crianças tenham sido consideradas fisicamente ativas em 12 estudos, seis estudos mostraram que elas despendiam muito tempo em CS. Os domínios de influência mais avaliados foram o individual (14 estudos) e o interpessoal (11 estudos), seguidos pelo ambiental (oito estudos) e o político (um estudo). As intervenções no contexto escolar (quatro estudos) aumentaram os níveis de AF e diminuíram o tempo em CS. Entretanto, as evidências dos estudos transversais e de intervenção apresentaram alto risco de viés. Conclusão. Diante das lacunas identificadas, recomendam-se estudos com delineamentos robustos que incluam mais países sul-americanos, com foco em bebês e crianças com menos de 3 anos de idade e que investiguem correlatos dos domínios ambiental e político.

Giardia doudenalis (lamblia, intestinalis) is a protozoan parasite that inhabits the lumen of the upper small intestine of vertebrates, causing chronic abdominal pains and severe diarrhea, symptoms of giardiasis, a persistent and recurrent infection. This characteristic is mainly due to the presence of membrane variant-specific surface proteins (VSPs) that give this parasite the ability to successively infect the host through antigenic variation. Using high-resolution scanning microscopy (HR-SM), we observed the presence, formation, and extension of tunneling-nanotube-like surface structures in Giardia, especially following parasite challenges with VSP antibodies. They were seen all over the parasite surface, both in vitro and in vivo, showing that G. duodenalis nanotube formation occurs in complex environments such as the gut. In addition, we also observed that some of these nanotubes displayed a periodic strangulation that produces 100 nm vesicles that seemed to be released in a process similar to that previously observed in Trypanosoma brucei. The presence of nanotube-like structures in G. duodenalis highlights yet another strategy of cellular communication utilized by these parasites, whether between themselves or with the host cell. [ABSTRACT FROM AUTHOR]

Virulence of apicomplexan parasites is based on their ability to divide rapidly to produce significant biomass. The regulation of their cell cycle is therefore key to their pathogenesis. Phosphorylation is a crucial posttranslational modification that regulates many aspects of the eukaryotic cell cycle. The phosphatase PP1 is known to play a major role in the phosphorylation balance in eukaryotes. We explored the role of TgPP1 during the cell cycle of the tachyzoite form of the apicomplexan parasite Toxoplasma gondii. Using a conditional mutant strain, we show that TgPP1 regulates many aspects of the cell cycle including the proper assembly of the daughter cells' inner membrane complex (IMC), the segregation of organelles, and nuclear division. Unexpectedly, depletion of TgPP1 also results in the accumulation of amylopectin, a storage polysaccharide that is usually found in the latent bradyzoite form of the parasite. Using transcriptomics and phospho-proteomics, we show that TgPP1 mainly acts through posttranslational mechanisms by dephosphorylating target proteins including IMC proteins. TgPP1 also dephosphorylates a protein bearing a starch-binding domain. Mutagenesis analysis reveals that the targeted phospho-sites are linked to the ability of the parasite to regulate amylopectin steady-state levels. Therefore, we show that TgPP1 has pleiotropic roles during the tachyzoite cell cycle regulation, but also regulates amylopectin accumulation. Rapid division and biomass production are important for apicomplexan parasite virulence. This study shows that the phosphatase TgPP1 in Toxoplasma gondii regulates the cell cycle and amylopectin accumulation by dephosphorylating inner membrane complex and starch-binding domain proteins. [ABSTRACT FROM AUTHOR]

Purpose: COVID-19 (coronavirus disease 2019) is an infectious disease caused by SARS-CoV-2, first reported in 2019 in Wuhan, China. Among the common complications is a pro-inflammatory and hypercoagulative response that compromises the vasculature among various organs. Methods: In this report, we present the postmortem retinal findings of five patients observed by means of optical microscopy and transmission and scanning electron microscopy techniques. Results: Clinical manifestations such as retinal hemorrhages and exacerbated inflammatory infiltrate, altered ultra structure with swollen mitochondria and pyknotic cells in both layers of the retina were observed in all analyzed eyes. Conclusion: Our data point to the fragility of this tissue in cases of severe COVID-19. [ABSTRACT FROM AUTHOR]

Temperature is a determining factor for the viral cycle. In this study, we investigate the effect of different temperatures on the cycles of two important arboviruses—Zika (ZIKV) and Chikungunya (CHIKV)—in Vero (mammalian) and C6/36 (mosquito) cells. We compare genome quantification to infectivity at 28 °C and 37 °C in both cell types. Virus–cell interaction was also examined by transmission electron microscopy, allowing the observation of phenomena such as virus-surfing and giant forms for CHIKV, as well as the the scarcity of ZIKV in C6/36 cells compared to its cycle in mammalian cells. [ABSTRACT FROM AUTHOR]

Trichomonas vaginalis is a common sexually transmitted parasite that colonizes the human urogenital tract, where it remains extracellular and adheres to epithelial cells. Infections range from asymptomatic to highly inflammatory, depending on the host and the parasite strain. Despite the serious consequences associated with trichomoniasis disease, little is known about parasite or host factors involved in attachment of the parasite-to-host epithelial cells. Here, we report the identification of microvesicle-like structures (MVs) released by T. vaginalis. MVs are considered universal transport vehicles for intercellular communication as they can incorporate peptides, proteins, lipids, miRNA, and mRNA, all of which can be transferred to target cells through receptor-ligand interactions, fusion with the cell membrane, and delivery of a functional cargo to the cytoplasm of the target cell. In the present study, we demonstrated that T. vaginalis release MVs from the plasma and the flagellar membranes of the parasite. We performed proteomic profiling of these structures demonstrating that they possess physical characteristics similar to mammalian extracellular vesicles and might be selectively charged with specific protein content. In addition, we demonstrated that viable T. vaginalis parasites release large vesicles (LVs), membrane structures larger than 1 µm that are able to interact with other parasites and with the host cell. Finally, we show that both populations of vesicles present on the surface of T vaginalis are induced in the presence of host cells, consistent with a role in modulating cell interactions.