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Toxoplasma gondii's propensity to infect its host and cause disease is highly dependent on its ability to modulate host cell functions. One of the strategies the parasite uses to accomplish this is via the export of effector proteins from the secretory dense granules. Dense granule (GRA) proteins are known to play roles in nutrient acquisition, host cell cycle manipulation, and immune regulation. Here, we characterize a novel dense granule protein named GRA83, which localizes to the parasitophorous vacuole (PV) in tachyzoites and bradyzoites. Disruption of GRA83 results in increased virulence, weight loss, and parasitemia during the acute infection, as well as a marked increase in the cyst burden during the chronic infection. This increased parasitemia was associated with an accumulation of inflammatory infiltrates in tissues in both acute and chronic infections. Murine macrophages infected with ∆gra83 tachyzoites produced less interleukin-12 (IL-12) in vitro, which was confirmed with reduced IL-12 and interferon-gamma in vivo. This dysregulation of cytokines correlates with reduced nuclear translocation of the p65 subunit of the nuclear factor-κB (NF-κB) complex. While GRA15 similarly regulates NF-κB, infection with ∆gra83/∆gra15 parasites did not further reduce p65 translocation to the host cell nucleus, suggesting these GRAs function in converging pathways. We also used proximity labeling experiments to reveal candidate GRA83 interacting T. gondii-derived partners. Taken together, this work reveals a novel effector that stimulates the innate immune response, enabling the host to limit the parasite burden. Importance Toxoplasma gondii poses a significant public health concern as it is recognized as one of the leading foodborne pathogens in the United States. Infection with the parasite can cause congenital defects in neonates, life-threatening complications in immunosuppressed patients, and ocular disease. Specialized secretory organelles, including the dense granules, play an important role in the parasite's ability to efficiently invade and regulate components of the host's infection response machinery to limit parasite clearance and establish an acute infection. Toxoplasma's ability to avoid early clearance, while also successfully infecting the host long enough to establish a persistent chronic infection, is crucial in allowing for its transmission to a new host. While multiple GRAs directly modulate host signaling pathways, they do so in various ways highlighting the parasite's diverse arsenal of effectors that govern infection. Understanding how parasite-derived effectors harness host functions to evade defenses yet ensure a robust infection is important for understanding the complexity of the pathogen's tightly regulated infection. In this study, we characterize a novel secreted protein named GRA83 that stimulates the host cell's response to limit infection.

Uma série de fatores sociais, ambientais, psicológicos e genéticos estão associados à dependência da nicotina e às doenças tabaco-relacionadas. A relação entre raça e tabagismo talvez seja um dos tópicos mais inexplorados e menos discutidos no âmbito do controle do tabaco no Brasil. Este trabalho realizou uma análise qualitativa retrospectiva, a fim de verificar os dados disponíveis na literatura sobre a relação entre raça/etnicidade e tabagismo no Brasil. Os resultados encontrados demonstraram que as pessoas de origem africana têm maior risco de se tornarem tabagistas e de desenvolverem doenças tabaco-relacionadas. Apesar desse risco, foi verificado que poucos estudos, a respeito dessa relação, foram publicados no Brasil e se, por um lado, os determinantes sociais podem influenciar tal associação, por outro, estudos apontam também uma possível influência de fatores genéticos no tabagismo. Mais estudos seriam necessários para entender a relação raça e tabagismo e para se pensar políticas mais efetivas contra o tabagismo. Os resultados também apontam que possivelmente, em virtude do racismo estrutural, a população com ancestralidade africana no Brasil se tornou “invisível” para pesquisadores e formuladores de políticas de controle do tabaco.

The development of molecular genetics has greatly enhanced the study of the biology and pathology associated with parasites of the phylum Apicomplexa. While the molecular tools are highly developed for the apicomplexan Toxoplasma gondii, the closely related parasite Neospora caninum lacks efficient tools for genetic manipulation. To enable efficient homologous recombination in N. caninum, we targeted the Ku heterodimer DNA repair mechanism in the genomic reference strain, Nc-Liverpool (NcLiv), and show that deletion of Ku80 results in a destabilization and loss of its partner Ku70. Disruption of Ku80 generated parasites in which genes are efficiently epitope tagged and only short homology regions are required for gene knockouts. We used this improved strain to target novel nonessential genes encoding dense granule proteins that are unique to N. caninum or conserved in T. gondii. To expand the utility of this strain for essential genes, we developed the auxin-inducible degron system for N. caninum using parasite-specific promoters. As a proof of concept, we knocked down a novel nuclear factor in both N. caninum and T. gondii and showed that it is essential for survival of both parasites. Together, these efficient knockout and knockdown technologies will enable the field to unravel specific gene functions in N. caninum, which is likely to aid in the identification of targets responsible for the phenotypic differences observed between these two closely related apicomplexan parasites. IMPORTANCE Neospora caninum is a parasite with veterinary relevance, inducing severe disease in dogs and reproductive disorders in ruminants, especially cattle, leading to major losses. The close phylogenetic relationship to Toxoplasma gondii and the lack of pathogenicity in humans drives an interest of the scientific community toward using N. caninum as a model to study the pathogenicity of T. gondii. To enable this comparison, it is important to develop efficient molecular tools for N. caninum, to gain accuracy and save time in genetic manipulation protocols. Here, we have developed base strains and protocols using the genomic reference strain of N. caninum to enable efficient knockout and knockdown assays in this model. We demonstrate that these tools are effective in targeting known and previously unexplored genes. Thus, these tools will greatly improve the study of this protozoan, as well as enhance its ability to serve as a model to understand other apicomplexan parasites.

The purpose of Maturity Models (MMs) is to assess, by focusing on skills, the level of performance of organizations, projects, or processes. In the civil construction sector, MMs were investigated with a view to evaluating the integration of sustainability in single/multifamily housebuilding projects. However, these models were found to be insufficient to evaluate projects in a balanced way, which take the three pillars of sustainability into consideration throughout their life cycle. In addition, there was a need to incorporate the evaluation of technical elements, thereby enabling opportunities to be identified for improving technologies, information systems and materials, which would result in maximizing operational efficiency. In this context, this article presents a management tool to evaluate the performance of sustainability in single/multifamily building projects. Using a mixed methods research approach, a systematic literature review was conducted to identify the main sustainable practices adopted in civil construction. Based on this, the Sustainable Building Site Management Maturity Model (SBSM4) was developed, which underwent refinements using a consultation process with six experts, using the Delphi method. It encompasses 4 dimensions, 16 categories and 61 assessment attributes, covering the planning, design, construction, and post-construction stages. An application was carried out in a project that aimed to build 5,000 single-family houses. This tool can perform a complete analysis of the practices adopted, thus providing a deeper understanding of the level of sustainability achieved. The SBSM4 contributes to advancing sustainable management in the civil construction sector and provides a solid basis for decision-making and the continuous improvement of projects toward more sustainable civil construction. [ABSTRACT FROM AUTHOR]

[This corrects the article DOI: 10.3389/fmicb.2016.01456.].

This paper has been retracted at the request of the authors.

With customers looking for the highest level of services and reduction of cost on international trade of goods, shippers have recently begun to focus on the inland leg of containerized import/export, making the competition advance between 'seaport against seaport' to 'seaport-hinterland against seaport-hinterland'. Bearing this in mind, this paper seeks to assess the logistic costs and the import process time in order to identify how these factors influence seaport-hinterland customer's choice and what is the effect of these factors on the main actors' competitiveness. In terms of time, the findings indicate that dry ports have been operationally more efficient, with customs and delivery process faster than in seaports and extended gates. In terms of cost we have applied Monte-Carlo simulation in a case study in Brazil to assess stochastically the import cost considering multiple actors as options. The study makes practical contributions, showing the cost-efficient zone for each macro region in the studied area and simulating a hypothetical scenario, where multimodal transportation is a delivery option. Lastly, the study makes theoretical contributions, discussing the competitiveness environment in light of the literature, bringing relevant insights to aid customers' and practitioners decision-making. [ABSTRACT FROM AUTHOR]

Due to the high prevalence and economic impact of neosporosis, the development of safe and effective vaccines and therapies against this parasite has been a priority in the field and is crucial to limit horizontal and vertical transmission in natural hosts. Limited data is available regarding factors that regulate the immune response against this parasite and such knowledge is essential in order to understand Neospora caninum induced pathogenesis. Mitogen-activated protein kinases (MAPKs) govern diverse cellular processes, including growth, differentiation, apoptosis, and immune-mediated responses. In that sense, our goal was to understand the role of MAPKs during the infection by N. caninum. We found that p38 phosphorylation was quickly triggered in macrophages stimulated by live tachyzoites and antigen extracts, while its chemical inhibition resulted in upregulation of IL-12p40 production and augmented B7/MHC expression. In vivo blockade of p38 resulted in an amplified production of cytokines, which preceded a reduction in latent parasite burden and enhanced survival against the infection. Additionally, the experiments indicate that the p38 activation is induced by a mechanism that depends on GPCR, PI3K and AKT signaling pathways, and that the phenomena here observed is distinct that those induced by Toxoplasma gondii's GRA24 protein. Altogether, these results showed that N. caninum manipulates p38 phosphorylation in its favor, in order to downregulate the host's innate immune responses. Additionally, those results infer that active interference in this signaling pathway may be useful for the development of a new therapeutic strategy against neosporosis.