Search

O processo de expansão urbana tem resultado em aglomerados populacionais desordenados, o que causa problemas para a administração municipal. A fim de mitigar este tipo de problema, uma das maneiras de reorganizar o território está no conceito de policentrismo. Nesse conceito, há duas abordagens que analisam esses problemas e que buscam soluções para eles, a funcional e a morfológica. No que diz respeito à análise pela abordagem morfológica, o este trabalho de pesquisa objetivou a realização de análises que envolve renda, demografia e relevo, fatores que possam influenciar a estrutura da forma urbana do distrito de Ipiabas, um possível subcentro localizado no munícipio de Barra do Piraí, Rio de Janeiro. Para compreender a forma do distrito, as análises consistiram em: interpolar a localização das possíveis residências, representar a renda média per capta e a densidade demográfica, bem como modelar uma superfície que mostra classes de declividade. Os resultados mostram que a característica da forma urbana do distrito de Ipiabas está relacionada a topografia e que há predominância de assentamentos populacionais entre as encostas.

Plasmodium vivax ookinete surface protein, Pvs25 is a transmission-blocking vaccine (TBV) candidate for malaria. Pvs25 has four EGF-like domains containing 22 cysteine residues forming 11 intramolecular disulfide bonds and this structural feature makes recombinant expression of Pvs25 difficult. In this study, we report the high expression of recombinant Pvs25 as a soluble form in silkworm, Bombyx mori. The Pvs25 protein was purified from hemolymphs of larvae and pupae by affinity chromatography. In the Pvs25 expressed by silkworm, no isoform with inappropriate disulfide bonds was found, requiring no further purification step which is necessary in case of Pichia pastoris based expressions systems. The Pvs25 from silkworm were confirmed to be the molecularly uniform by sodium dodecyl sulfate gel electrophoresis analysis and size exclusion chromatography analysis. To examine the immunogenicity, the Pvs25 from B. mori, was administered to BALB/c mice by the subcutaneous (s.c.) route with the oil adjuvant. The Pvs25 produced by silkworm induced potent and robust immune response, and the induced antisera correctly recognized P. vivax ookinetes in vitro, demonstrating the potency of Pvs25 from silkworm as a TBV candidate for malaria. This is the first study that to construct a mass production system for malaria TBV antigens by the silkworm to the best of our knowledge.

Control measures have significantly reduced malaria morbidity and mortality in the last two decades; however, the downward trends have stalled and have become complicated by the emergence of COVID-19. Significant efforts have been made to develop malaria vaccines, but currently only the RTS,S/AS01 vaccine against Plasmodium falciparum has been recommended by the WHO, for widespread use among children in sub-Saharan Africa. The efficacy of RTS,S/AS01 is modest, and therefore the development of more efficacious vaccines is still needed. In addition, the development of transmission-blocking vaccines (TBVs) to reduce the parasite transmission from humans to mosquitoes is required toward the goal of malaria elimination. Few TBVs have reached clinical development, and challenges include low immunogenicity or high reactogenicity in humans. Therefore, novel approaches to accelerate TBV research and development are urgently needed, especially novel TBV candidate discovery. In this mini review we summarize the progress in TBV research and development, novel TBV candidate discovery, and discuss how to accelerate novel TBV candidate discovery.

Introduction: Highly effective malaria vaccines are essential component toward malaria elimination. Although the leading malaria vaccine, RTS,S/AS01, with modest efficacy is being evaluated in a pilot feasibility trial, development of a malaria transmission-blocking vaccine (TBV) could make a major contribution toward malaria elimination. Only a few TBV antigens have reached pre-clinical or clinical development but with several challenges including difficulties in the expression of malaria recombinant proteins and low immunogenicity in humans. Therefore, novel approaches to accelerate TBV research to preclinical development are critical to generate an efficacious TBV.Areas covered: PubMed was searched to review the progress and future prospects of malaria TBV research and development. We also reviewed registered trials at ClinicalTrials.gov as well as post-genome TBV candidate discovery research including our efforts.Expert opinion: Wheat germ cell-free protein synthesis technology can accelerate TBV development by overcoming some current challenges of TBV research.

The malaria parasite sporozoite sequentially invades mosquito salivary glands and mammalian hepatocytes; and is the Plasmodium lifecycle infective form mediating parasite transmission by the mosquito vector. The identification of several sporozoite-specific secretory proteins involved in invasion has revealed that sporozoite motility and specific recognition of target cells are crucial for transmission. It has also been demonstrated that some components of the invasion machinery are conserved between erythrocytic asexual and transmission stage parasites. The application of a sporozoite stage-specific gene knockdown system in the rodent malaria parasite, Plasmodium berghei, enables us to investigate the roles of such proteins previously intractable to study due to their essentiality for asexual intraerythrocytic stage development, the stage at which transgenic parasites are derived. Here, we focused on the rhoptry neck protein 11 (RON11) that contains multiple transmembrane domains and putative calcium-binding EF-hand domains. PbRON11 is localised to rhoptry organelles in both merozoites and sporozoites. To repress PbRON11 expression exclusively in sporozoites, we produced transgenic parasites using a promoter-swapping strategy. PbRON11-repressed sporozoites showed significant reduction in attachment and motility in vitro, and consequently failed to efficiently invade salivary glands. PbRON11 was also determined to be essential for sporozoite infection of the liver, the first step during transmission to the vertebrate host. RON11 is demonstrated to be crucial for sporozoite invasion of both target host cells - mosquito salivary glands and mammalian hepatocytes - via involvement in sporozoite motility.

Existing control measures have significantly reduced malaria morbidity and mortality in the last two decades, although these reductions are now stalling. Significant efforts have been undertaken to develop malaria vaccines. Recently, extensive progress in malaria vaccine development has been made for Plasmodium falciparum. To date, only the RTS,S/AS01 vaccine has been tested in Phase 3 clinical trials and is now under implementation, despite modest efficacy. Therefore, the development of a malaria transmission-blocking vaccine (TBV) will be essential for malaria elimination. Only a limited number of TBVs have reached pre-clinical or clinical development with several major challenges impeding their development, including low immunogenicity in humans. TBV development efforts against P. vivax, the second major cause of malaria morbidity, lag far behind those for P. falciparum. In this review we summarize the latest progress, challenges and innovations in P. vivax TBV research and discuss how to accelerate its development.

Plasmodium parasites cause malaria in mammalian hosts and are transmitted by Anopheles mosquitoes. Activated gametocytes in the mosquito midgut egress from erythrocytes followed by fertilization and zygote formation. Zygotes differentiate into motile invasive ookinetes, which penetrate the midgut epithelium before forming oocysts beneath the basal lamina. Ookinete development and traversal across the mosquito midgut wall are major bottlenecks in the parasite life cycle. In ookinetes, surface proteins and proteins stored in apical organelles have been shown to be involved in parasite-host interactions. A group of ookinete proteins that are predicted to have such functions are named PSOPs (putative secreted ookinete protein). PSOP1 is possibly involved in migration through the midgut wall, and here its subcellular localization was examined in ookinetes by immunoelectron microscopy. PSOP1 localizes to the micronemes of Plasmodium yoelii and Plasmodium berghei ookinetes, indicating that it is stored and possibly apically secreted during ookinete penetration through the mosquito midgut wall.

The main objective of this research is to evaluate the reading time of street names on dynamic egocentrically referenced maps for In-Car Route Guidance and Navigation Systems. Two different road network patterns (grid-like or non-grid-like) were considered and tasks were devised to search for street names in two different route segments (where the driver was, or where the driver would have to manoeuvre). Considering a non-grid-like road network pattern, for the task of searching for the name of a road where the driver would manoeuvre, street names aligned horizontally and next to the route were read significantly faster than street names positioned along the route. Street names positioned obliquely required more reading time than street names aligned horizontally. Dynamic maps egocentrically referenced should present street names horizontally aligned and next to the route for the segment related to where the driver will manoeuvre, for both road network patterns. Also, Street names should be positioned next to the car symbol. Resumo: O principal objetivo desta pesquisa é avaliar o tempo de leitura de nomes de vias em mapas dinâmicos referenciados egocentricamente para sistemas de navegação e guias de rotas em automóvel. Foram considerados dois padrões diferentes de rede viária (regular ou não regular) e as tarefas de leitura foram planejadas para encontrar e ler nomes de vias em dois segmentos de rota diferentes (onde o motorista estava ou onde o motorista teria que manobrar). Considerando um padrão de rede viária irregular, para a tarefa de encontrar e ler o nome de uma via onde o motorista manobraria, os nomes das vias alinhados horizontalmente e próximos à via foram lidos significativamente mais rápido do que os nomes das vias posicionados ao longo da rota. Nomes de vias posicionados obliquamente exigem mais tempo de leitura do que nomes de vias alinhados horizontalmente. Os mapas dinâmicos referenciados egocentricamente deveriam apresentar nomes de vias alinhados horizontalmente e próximos à rota para o segmento relacionado ao qual o motorista irá manobrar, para ambos os padrões de rede viária. Além disso, os nomes das vias deveriam ser posicionados próximo do símbolo do automóvel.

Made available in DSpace on 2020-12-12T02:21:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01. Added 1 bitstream(s) on 2021-07-15T15:26:00Z : No. of bitstreams: 1 S1982-21702020000200200.pdf: 2791642 bytes, checksum: d0c800693df1905e51104ae086117503 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Housing Market appraisal studies generally apply classic regression models, whose parameters are globally estimated. However, the use of the Geographically Weighted Regression (GWR) model, allows the parameters to be locally estimated, increasing its precision. The aim of this article is to apply the GWR model to a sample of 82 apartments, in order to create a plan of values of some districts of the West Zone of Rio de Janeiro city, Brazil. With the proposed methodology, GWR and kernel estimator, it is possible to generate a surface of values. The performance of the surface of values was assessed with (i) cross-validation between the kernel functions, with the Root-Mean Square Standardized (RMSS) error; and with (ii) the GWR adjustment factors to determine the ideal bandwidth. The contribution of generating a surface of values with geographical location via kernel estimator lies on supporting apartment pricing, such as in calculating the venal value of apartments of the West Zone of Rio de Janeiro city, besides being applied in IPTU-Imposto sobre Propriedade Predial e Territorial (The Urban Real Estate Property Tax) and ITBI-Imposto de Transmissão de Bens Imóveis (Tax on the Transfer of Real Estate) and ITBI collection. Universidade Estadual Paulista-UNESP Faculdade de Ciência e Tecnologia Departamento de Cartográfica Universidade Federal Rural do Rio de Janeiro-UFRRJ Instituto de Tecnologia Departamento de Engenharia Universidade Estadual Paulista-UNESP Faculdade de Ciência e Tecnologia Departamento de Estatística Universidade Estadual Paulista-UNESP Faculdade de Ciência e Tecnologia Departamento de Cartográfica Universidade Estadual Paulista-UNESP Faculdade de Ciência e Tecnologia Departamento de Estatística CAPES: 88882.433940/2019-01

Malaria transmission-blocking vaccines (TBVs) aim to inhibit parasite fertilization or further development within the mosquito midgut. Because TBV-immunized individuals reduce the transmission of malaria parasites to mosquito vectors, TBVs could serve as a promising strategy to eliminate malaria. We previously reported that a male specific protein, PyMiGS (Plasmodium yoelii microgamete surface protein), is localized to the surface of microgametes and anti-PyMiGS antibodies have strong transmission-blocking activity. In this study we determine a region of PyMiGS that contains epitopes inducing potent transmission-blocking antibodies. PyMiGS excluding the N-terminal signal sequence and C-terminal hydrophobic region (PyMiGS-full) was divided into five overlapping regions, named I through V, and corresponding truncated recombinant proteins were produced. Anti-region V antibody, affinity-purified from anti-PyMiGS-full rabbit antiserum, significantly reduced the number of oocysts in a mosquito membrane-feeding assay. Antibodies from mice immunized with PyMiGS-V recognized the microgamete surface and showed higher transmission-blocking efficacy than antibodies obtained by PyMiGS-full immunization. These results indicate that the major epitopes for transmission-blocking antibodies are within region V at the C-terminal region of PyMiGS. Therefore, region V of MiGS could be a promising pre-fertilization TBV candidate antigen.

Made available in DSpace on 2019-10-06T17:04:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) European Commission The development of Global Navigation Satellite Systems (GNSS) was a revolution in activities related to positioning. Currently, GLONASS (Global'naya Navigatsionnaya Sputnikovaya Sistema) and GPS (Global Positioning System) are the main systems with full constellation. The use of GPS and GLONASS combined data gained renewed attention after the GLONASS restoration and modernization plan, which enabled the system to reach full constellation in 2011. In addition to the use of combined data, several other factors can influence positioning quality, such as the methods applied and errors that can affect the transmitted signals. Concerning errors, the ionosphere is an important source, particularly for users of single frequency receivers. This requires special attention, because, in addition to degradation of positioning accuracy, there is a great interdependency between signal loss and ionospheric irregularities, such as ionospheric scintillation. In this paper, multivariate analysis techniques were applied to investigate the influence of ionospheric activity, specifically ionospheric scintillation, in positioning error. An experiment was carried out applying the point positioning method considering stations located in different places during periods of high and low ionospheric activity. The results showed high similarity between GPS and GLONASS data and significant ionosphere influence in the positioning error. S4 indexes presented correlations higher than 0.75 when considering GPS and GLONASS data. Positioning error using GPS or GPS/GLONASS data presented correlations higher than 0.93 for all stations considered. Techniques such as clustering, correspondence analysis and factor analysis were also applied in this study. São Paulo State University – UNESP, Roberto Simonsen, 305 São Paulo State University – UNESP, Roberto Simonsen, 305 CAPES: 06/04008-2

Vegetation mapping requires information about trees and underlying vegetation to ensure proper management of the urban and forest environments. This information can be obtained using remote sensors. For instance, lightweight systems composed of Unmanned Aerial Vehicles (UAVs) as a platform, low-cost laser units and the recent miniaturized navigation sensors (positioning and orientation) have become a very feasible and flexible alternative. Low-cost UAV-ALS systems usually provide centimetric accuracy in altimetry, according to flight data configuration and quality of observations. This paper presents a feasibility study of a lightweight ALS system on-board a UAV to estimate the diameters at breast height (DBH) of urban trees using LiDAR data and linear regression model. A mathematical model correlating the crown diameter and height of the tree to estimate the DBH was developed based on a linear regression with stepwise method. The stepwise linear regression method enables the addition and the removal of predictor variables through statistical tests. The tree samples were separated in two classes (A and B), according to the diametric distribution. These sample classes were used to define two linear regression models. The regression models that best fit the samples achieved an R2 adj value above 94% for class A and B, which demonstrates the closeness between the samples and the developed mathematical models. The quality control of the proposed regression models was performed comparing the DBH values estimated and directly measured (reference). DBH of the trees were estimated with an average discrepancy of 8.7 cm.

O objetivo deste trabalho é avaliar a preferência entre mapa 2D e mapa 3D, para a tarefa de manutenção em rota durante a navegação em automóvel. Para tanto, um total de 18 mapas foi projetado a partir da consideração de três ângulos de inclinação para a câmera (89°, 45°, 30°), cada um com três variações de distância entre o carro e a manobra (500 m, 250 m, 50 m), bem como o tipo de manobra (simples ou complexo / rotatória). Um grupo de 30 motoristas experientes com sistema de navegação em automóvel participou de um experimento. Os resultados indicam que a maioria dos motoristas preferiram o mapa 3D quando estão se preparando para manobrar nas rotatórias. No entanto, os mapas 3D com baixo ângulo de inclinação da câmera (30°) foram os menos preferidos para auxiliar na manobra simples. De acordo com as razões apontadas, o mapa 2D facilitou estimar distâncias, e o mapa 3D apresentou maior quantidade de informação, relacionada ao segmento de rota a ser seguido, além de favorecer a correspondência entre a visão em perspectiva e a vista ao longo da via. As considerações encontradas podem apoiar a indústria automotiva no processo de seleção do design do mapa para diferentes tarefas de navegação em automóvel.

Plasmodium falciparum proteins involved in vascular endothelial cell adherence are transported to the surface of infected erythrocytes. These proteins are exported through parasite-derived membrane structures within the erythrocyte cytoplasm called Maurer's clefts. Skeleton binding protein 1 (SBP1) is localized in the Maurer's clefts and plays an important role in transporting molecules to the surface of infected erythrocytes. Details of the translocation pathway are unclear and in this study we focused on the subcellular localization of SBP1 at an early intraerythrocytic stage. We performed immunoelectron microscopy using specific anti-SBP1 antibodies generated by immunization with recombinant SBP1 of P. falciparum. At the early trophozoite (ring form) stage, SBP1 was detected within an electron dense material (EDM) found in the parasite cytoplasm and in the parasitophorous vacuolar (PV) space. These findings demonstrate that SBP1 accumulates in EDM in the early trophozoite cytoplasm and is transported to the PV space before translocation to the Maurer's clefts formed in the erythrocyte cytoplasm.

A transmission-blocking vaccine (TBV) against Plasmodium falciparum is likely to be a valuable tool in a malaria eradication program. Pfs230 is one of the major TBV candidates, and multiple Pfs230-based vaccines induced antibodies, which prevented oocyst formation in mosquitoes as determined by a standard membrane-feeding assay (SMFA). Pfs230 is a >300 kDa protein consisting of 14 cysteine motif (CM) domains, and the size and cysteine-rich nature of the molecule have hampered its production as an intact protein. Except for one early study with maltose-binding protein fusion Pfs230 constructs expressed in Esherichia coli, all other studies have focused on only the first four CM domains in the Pfs230 molecule. To identify all possible TBV candidate domains, we systematically produced either single-CM-domain (a total of 14), 2-CM-domain (7), or 4-CM-domain (6) recombinant protein fragments using a eukaryotic wheat germ cell-free expression system (WGCFS). In addition, two more constructs which covered previously published regions, and an N-terminal prodomain construct spanning the natural cleavage site of Pfs230 were produced. Antisera against each fragment were generated in mice and we evaluated the reactivity to native Pfs230 protein by Western blots and immunofluorescence assay (IFA), and functionality by SMFA. All 30 WGCFS-produced Pfs230 constructs were immunogenic in mice. Approximately half of the mouse antibodies specifically recognized native Pfs230 by Western blots with variable band intensities. Among them, seven antibodies showed higher reactivities against native Pfs230 determined by IFA. Interestingly, antibodies against all protein fragments containing CM domain 1 displayed strong inhibitions in SMFA, while antibodies generated using constructs without CM domain 1 showed no inhibition. The results strongly support the concept that future Pfs230-based vaccine development should focus on the Pfs230 CM domain 1.

Made available in DSpace on 2018-11-12T17:28:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-08-01. Added 1 bitstream(s) on 2018-11-12T17:36:59Z : No. of bitstreams: 1 S1982-21702018000300383.pdf: 869855 bytes, checksum: 24ab650287d6395c9b6d1753c59183a7 (MD5) Resumo Ruídos nos processos de comunicação da informação em interfaces de sistemas de navegação têm sobrecarregado o sistema de processamento cognitivo dos motoristas e aumentado as chances de acidentes de trânsito. Esse trabalho avalia a usabilidade de mapas em diferentes escalas para um protótipo de sistema de navegação e guia de rota em automóvel. Projetou-se mapas de acordo com os princípios da comunicação cartográfica, tal como segregação de figura-fundo e agrupamento perceptivo, bem como na demanda do usuário ao realizar a tarefa tática. Duas escalas foram adotadas, 1:3.000 a 1:6.000, e os mapas implementados no protótipo. Um total de 52 motoristas (26 homens e 26 mulheres) participaram de um experimento em simulador de direção. Os mapas representaram uma rota em área urbana composta por 13 manobras simples e 13 complexas. A carga mental de trabalho dos motoristas foi quantificada em termos de demanda visual, erro navegacional e preferência subjetiva. Os resultados mostram que a usabilidade dos mapas é influenciada pela variação da escala cartográfica, e isto está relacionado a complexidade da manobra. Além disso, a demanda visual está associada ao gênero do motorista, e isto tem relação com a habilidade espacial. Mais implicações são apresentadas e discutidas. Abstract Noise from the information communication process produced by the interfaces of navigation systems has overloaded drivers' cognitive processing systems and increased the probability of traffic accidents. This work evaluates the usability of maps of different scales in a prototype route guidance and navigation system. The maps were designed on basic cartographic communication principles, such as perceptive grouping and figure-ground segregation, as well drivers’ requirements for performing a tactical task. Two different scales were adopted, 1:3,000 and 1:6,000, and the maps implemented in the prototype. A total of 52 subjects (26 males and 26 females) participated in an experiment performed in a driving simulator. The maps describe an urban route composed of 13 simple and complex maneuvers. The drivers’ mental workload was measured in terms of visual demand, navigational error and subjective preference. Results reveal that the usability of maps is influenced by map scale variation, and this is related to maneuver complexity. Also, an association between drivers’ visual demand and gender was found, and this was related to drivers’ spatial ability. More implications are presented and discussed. Universidade do Oeste Paulista Pós-Graduação em Meio Ambiente e Desenvolvimento Regional Universidade Estadual Paulista Departamento de Cartografia Universidade Estadual Paulista Departamento de Cartografia

Invasion of host cells by apicomplexan parasites is mediated by proteins released from microneme, rhoptry, and dense granule secretory organelles located at the apical end of parasite invasive forms. Microneme secreted proteins establish interactions with host cell receptors and induce exocytosis of the rhoptry organelle. Rhoptry proteins are involved in target cell invasion as well as the formation of the parasitophorous vacuole in which parasites reside during development within the host cell. In Plasmodium merozoites, the rhoptry neck protein (RON) complex consists of RON2, RON4, and RON5, and interacts with apical membrane antigen 1 (AMA1) as a critical structure of the invasion moving junction. PfRON12 is known to localize to the rhoptry neck of merozoites, but its function remains obscure. The roles of RON proteins are largely unknown in sporozoites, the second invasive form of Plasmodium which possesses a conserved apical end secretory structure. Here, we confirm that RON12 is expressed in the rhoptry neck of merozoites in rodent malaria parasites, whereas in contrast we show that RON12 is localized to the rhoptry body in sporozoites. Phenotypic analysis of Plasmodium berghei ron12-disrupted mutants revealed that RON12 is dispensable for sporogony, invasion of mosquito salivary glands and mouse hepatocytes, and development in hepatocytes.

Malaria transmission-blocking vaccines aim to inhibit the development of malaria parasites in mosquitoes by inducing antibodies targeting surface proteins of sexual stage parasites. We have recently identified PyMiGS, a protein specifically expressed in the osmiophilic body of male gametocytes of Plasmodium yoelii (Py). PyMiGS is translocated to the surface of microgametes, and potent transmission-blocking activity was observed in mosquitoes fed on mice passively immunized with antibodies against PyMiGS. Here we demonstrate using a direct feeding assay that recombinant PyMiGS successfully induces anti-PyMiGS antibodies in mice and that the antibodies block parasite development in mosquitoes. We also show using the membrane-feeding assay that rabbit anti-PyMiGS antibody inhibits parasite development in mosquitoes in a dose-dependent manner without complement involvement. To investigate the mode of action of anti-PyMiGS antibodies against parasite development, we observed exflagellation after mixing Py gametocytes with activation medium containing anti-PyMiGS or anti-GST control antibodies. Whereas most microgametes were released from activated male gametocytes in the control group, a significantly reduced number of microgametes were released in the anti-PyMiGS group, with most of the microgametes left attached to the activated male gametocytes. Moreover, anti-PyMiGS antibodies shortened the duration of the active movement of microgametes after the onset of exflagellation. Taken together, these findings suggest that anti-PyMiGS antibodies bind to the microgamete surface immediately after exflagellation, thereby reducing microgamete motility and inhibiting microgamete release from the activated male gametocytes. These results strongly suggest that PyMiGS orthologues in Plasmodium falciparum and Plasmodium vivax can be promising TBV candidates.

Apical organellar proteins in Plasmodium falciparum merozoites play important roles upon invasion. To date, dense granule, the least studied apical organelle, secretes parasite proteins across the parasitophorous vacuole membrane (PVM) to remodel the infected erythrocyte. Although this phenomenon is key to parasite growth and virulence, only five proteins so far have been identified as dense granule proteins. Further elucidation of dense granule molecule(s) is therefore required. P. falciparum Exported Protein (EXP) 1, previously reported as a parasitophorous vacuole membrane (PVM) protein, is considered essential for parasite growth. In this study, we characterized EXP1 using specific anti-EXP1 antibodies generated by immunization of wheat germ cell-free produced recombinant EXP1. Immunofluorescence microscopy (IFA) demonstrated that EXP1 co-localized with RESA, indicating that the protein is initially localized to dense granules in merozoites, followed by translocation to the PVM. The EXP1 localization in dense granule of merozoites and its translocation to the PVM after invasion of erythrocytes were further confirmed by immunoelectron microscopy. Here, we demonstrate that EXP1 is one of the dense granule proteins in merozoites, which is then transported to the PVM after invasion.

Malaria transmission-blocking vaccines (TBV) aim to interfere with the development of the malaria parasite in the mosquito vector, and thus prevent spread of transmission in a community. To date three TBV candidates have been identified in Plasmodium vivax; namely, the gametocyte/gamete protein Pvs230, and the ookinete surface proteins Pvs25 and Pvs28. The Plasmodium falciparum gametocyte/gamete stage proteins Pfs48/45 and Pfs47 have been studied as TBV candidates, and Pfs48/45 shown to induce transmission-blocking antibodies, but the candidacy of their orthologs in P. vivax, Pvs48/45 (PVX_083235) and Pvs47 (PVX_083240), for vivax TBV have not been tested. Herein we investigated whether targeting Pvs48/45 and Pvs47 can inhibit parasite transmission to mosquitoes, using P. vivax isolates obtained in Thailand. Mouse antisera directed against the products from plasmids expressing Pvs48/45 and Pvs47 detected proteins of approximately 45- and 40-kDa, respectively, in the P. vivax gametocyte lysate, by Western blot analysis under non-reducing conditions. In immunofluorescence assays Pvs48/45 was detected predominantly on the surface and Pvs47 was detected in the cytoplasm of gametocytes. Membrane feeding transmission assays demonstrated that anti-Pvs48/45 and -Pvs47 mouse sera significantly reduced the number of P. vivax oocysts developing in the mosquito midgut. Limited amino acid polymorphism of these proteins was observed among 27 P. vivax isolates obtained from Thailand, Vanuatu, and Colombia; suggesting that polymorphism may not be an impediment for the utilization of Pvs48/45 and Pvs47 as TBV antigens. In one Thai isolate we found that the fourth cysteine residue in the Pvs47 cysteine-rich domain (CRD) III (amino acid position 337) is substituted to phenylalanine. However, antibodies targeting Pvs47 CRDI-III showed a significant transmission-reducing activity against this isolate, suggesting that this substitution in Pvs47 was not critical for recognition by the generated antibodies. In conclusion, our results indicate that Pvs48/45 and Pvs47 are potential transmission-blocking vaccine candidates of P. vivax.

The classification is an important step in the extraction of geometric primitives from LiDAR data. Normally, it is applied for the identification of points sampled on geometric primitives of interest. In the literature there are several studies that have explored the use of eigenvalues to classify LiDAR points into different classes or structures, such as corner, edge, and plane. However, in some works the classes are defined considering an ideal geometry, which can be affected by the inadequate sampling and/or by the presence of noise when using real data. To overcome this limitation, in this paper is proposed the use of metrics based on eigenvalues and the k-means method to carry out the classification. So, the concept of principal component analysis is used to obtain the eigenvalues and the derived metrics, while the k-means is applied to cluster the roof points in two classes: edge and non-edge. To evaluate the proposed method four test areas with different levels of complexity were selected. From the qualitative and quantitative analyses, it could be concluded that the proposed classification procedure gave satisfactory results, resulting in completeness and correctness above 92% for the non-edge class, and between 61% to 98% for the edge class. Resumo: A classificação é uma importante etapa na extração de primitivas geométricas sobre dados LiDAR. Normalmente, a classificação é utilizada para identificar os pontos amostrados sobre primitivas de interesse. Na literatura são encontrados vários trabalhos que exploram o uso dos autovalores para classificar os pontos LiDAR em diferentes estruturas ou classes, tais como: quina, borda, e plano. Entretanto, alguns trabalhos desenvolvidos se baseiam em parâmetros obtidos a partir de uma geometria ideal, que pode fornecer resultados não adequados quando a amostragem for insuficiente ou quando da presença de ruídos. Para contornar esta limitação, é proposto o uso de métricas estimadas a partir de autovalores e do uso do método k-médias. O conceito de análise de componentes principais é utilizado para determinar os autovalores e algumas métricas derivadas, enquanto que o método k-médias é aplicado para agrupar os pontos de telhados em duas classes: borda e não borda. Para avaliar a metodologia foram selecionadas quatro áreas teste com diferentes níveis de complexidade. A partir dos resultados, foi possível concluir que o procedimento de classificação apresentou resultados satisfatórios, obtendo-se nível de acerto e completeza acima de 92% para os pontos da classe não borda e entre 61% e 98% para a classe borda.

The target molecules of antibodies against falciparum malaria remain largely unknown. Recently we have identified multiple proteins as targets of immunity against Plasmodium falciparum using African serum samples. To investigate whether potential targets of clinical immunity differ with transmission intensity, we assessed immune responses in residents of low malaria transmission region in Thailand. Malaria asymptomatic volunteers (Asy: n = 19) and symptomatic patients (Sym: n = 21) were enrolled into the study. Serum immunoreactivity to 186 wheat germ cell-free system (WGCFS)-synthesized recombinant P. falciparum asexual-blood stage proteins were determined by AlphaScreen, and subsequently compared between the study groups. Forty proteins were determined as immunoreactive with antibody responses to 35 proteins being higher in Asy group than in Sym group. Among the 35 proteins, antibodies to MSP3, MSPDBL1, RH2b, and MSP7 were significantly higher in Asy than Sym (unadjusted p < 0.005) suggesting these antigens may have a protective role in clinical malaria. MSP3 reactivity remained significantly different between Asy and Sym groups even after multiple comparison adjustments (adjusted p = 0.033). Interestingly, while our two preceding studies using African sera were conducted differently (e.g., cross-sectional vs. longitudinal design, observed clinical manifestation vs. functional activity), those studies similarly identified MSP3 and MSPDBL1 as potential targets of protective immunity. This study further provides a strong rationale for the application of WGCFS-based immunoprofiling to malaria vaccine candidate and biomarker discovery even in low or reduced malaria transmission settings.

Plasmodium parasites cause malaria in mammalian hosts and are transmitted by Anopheles mosquitoes. Gametocytes, which differentiate from asexual-stage parasites, are activated by environmental changes when ingested into the mosquito midgut, and are rapidly released from erythrocytes prior to fertilization. Secretory proteins localized to osmiophilic bodies (OBs), organelles unique to gametocytes, have been reported to be involved in female gametocyte egress. In this study, we investigate the dynamics of OBs in activated gametocytes of Plasmodium falciparum and Plasmodium yoelii using the female OB-specific marker protein, G377. After activation, female gametocyte OBs migrate to the parasite surface and fuse to form large vesicles beneath the parasite plasma membrane. At the marginal region of female gametocytes, fused vesicles secrete contents by exocytosis into the parasitophorous vacuole space, prior to parasite egress via the break-down of the erythrocyte membrane. This is the first detailed description of how proteins are transported through osmiophilic bodies.

Malaria parasites proliferate by repeated invasion of and multiplication within erythrocytes in the vertebrate host. Sexually committed intraerythrocytic parasites undergo sexual stage differentiation to become gametocytes. After ingestion by the mosquito, male and female gametocytes egress from erythrocytes and fertilize within the mosquito midgut. A complex signaling pathway likely responds to environmental events to trigger gametogenesis and regulate fertilization; however, such knowledge remains limited for malaria parasites. Several pseudokinases are highly transcribed at the gametocyte stage and are possible multi-functional regulators controlling critical steps of the life cycle. Here we characterized one pseudokinase, termed PypPK1, in Plasmodium yoelii that is highly expressed in schizonts and male gametocytes. Immunofluorescence assays for parasites expressing Myc-tagged PypPK1 confirmed that PypPK1 protein is expressed in schizonts and sexual stage parasites. Transgenic ΔpPK1 parasites, in which the PypPK1 gene locus was deleted by the CRISPR/Cas9 method, showed significant growth defect and reduced virulence in mice. In the blood stage, ΔpPK1 parasites were able to egress from erythrocytes similar to wild type parasites; however, erythrocyte invasion efficacy was significantly reduced. During sexual stage development, no clear changes were seen in male and female gametocytemias as well as gametocyte egress from erythrocytes; but, the number of exflagellation centers and oocysts were significantly reduced in ΔpPK1 parasites. Taken together, PypPK1 has an important role for both erythrocyte invasion and exflagellation center formation., Parasitology International, 76, art.no.102056; 2020

O objetivo foi analisar a qualidade de vida de participantes de um programa de Ginástica Laboral. O estudo observou 48 indivíduos, pertencentes do programa Saúde Integral do Trabalhador, com idade entre 36 e 67 anos ( =50,0±8,9 anos), sendo 11 mulheres e 37 homens. Para avaliação da Qualidade de Vida, foi utilizado o instrumento genérico Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Após a aplicação dos questionários, as informações coletadas foram armazenadas em único banco de dados em Epi Info 2000. Foram observadas as variáveis relatadas por sintomas de “dor, aspectos sociais e funcionais”. A amostra analisada mostrou valores de pontuação acima de 50 pontos (mediana). Além disso, o domínio “dor” foi o único a apresentar valores inferiores ao ponto estabelecido pela mediana. Concluímos que o programa de ginástica laboral pode contribuir para a melhora destes aspectos, principalmente naqueles que demonstram menores valores.

Malaria causes about 216 million clinical cases and 0.7 million deaths annually. One promising route to address malaria is vaccination. However, so far, not even a single licensed malaria vaccine has been developed. Even the effectiveness of RTS,S, the world's most advanced malaria vaccine candidate (MVC) in clinical trials, is less than 50% efficacy against the disease. This backdrop indicates that the search for a truly effective vaccine is far from over and galvanizes us to expand the arsenal of promising MVC antigens to include in a next generation subunit vaccine. In our previous proof of principle studies, we have found that the wheat germ cell-free protein synthesis system (WGCFS) is one of the optimal tools for synthesis of quality malaria proteins and hence the identification of novel MVCs. This review summarizes the initial progresses so far made regarding the identification of novel MVCs using WGCFS.