Immunoregulation in human malaria: the challenge of understanding asymptomatic infection

Asymptomatic Plasmodium infection carriers represent a major threat to malaria control worldwide as they are silent natural reservoirs and do not seek medical care. There are no standard criteria for asymptomaticPlasmodium infection; therefore, its diagnosis relies on the presence of the parasite during a specific period of symptomless infection. The antiparasitic immune response can result in reducedPlasmodium sp. load with control of disease manifestations, which leads to asymptomatic infection. Both the innate and adaptive immune responses seem to play major roles in asymptomatic Plasmodiuminfection; T regulatory cell activity (through the production of interleukin-10 and transforming growth factor-β) and B-cells (with a broad antibody response) both play prominent roles. Furthermore, molecules involved in the haem detoxification pathway (such as haptoglobin and haeme oxygenase-1) and iron metabolism (ferritin and activated c-Jun N-terminal kinase) have emerged in recent years as potential biomarkers and thus are helping to unravel the immune response underlying asymptomatic Plasmodium infection. The acquisition of large data sets and the use of robust statistical tools, including network analysis, associated with well-designed malaria studies will likely help elucidate the immune mechanisms responsible for asymptomatic infection

Critical neuropsychobiological analysis of panic attack- and anticipatory anxiety-like behaviors in rodents confronted with snakes in polygonal arenas and complex labyrinths: a comparison to the elevated plus- and T-maze behavioral tests

Objective: To compare prey and snake paradigms performed in complex environments to the elevated plus-maze (EPM) and T-maze (ETM) tests for the study of panic attack- and anticipatory anxiety-like behaviors in rodents. Methods: PubMed was reviewed in search of articles focusing on the plus maze test, EPM, and ETM, as well as on defensive behaviors displayed by threatened rodents. In addition, the authors’ research with polygonal arenas and complex labyrinth (designed by the first author for confrontation between snakes and small rodents) was examined. Results: The EPM and ETM tests evoke anxiety/fear-related defensive responses that are pharmacologically validated, whereas the confrontation between rodents and snakes in polygonal arenas with or without shelters or in the complex labyrinth offers ethological conditions for studying more complex defensive behaviors and the effects of anxiolytic and panicolytic drugs. Prey vs. predator paradigms also allow discrimination between non-oriented and oriented escape behavior. Conclusions: Both EPM and ETM simple labyrinths are excellent apparatuses for the study of anxiety- and instinctive fear-related responses, respectively. The confrontation between rodents and snakes in polygonal arenas, however, offers a more ethological environment for addressing both unconditioned and conditioned fear-induced behaviors and the effects of anxiolytic and panicolytic drugs

Esquistossomose do sistema nervoso central relato de um caso

O comprometimento do sistema nervoso na esquistossomose mansônica é evento raramente diagnosticado na evolução desta parasitose. Os autores descrevem o caso de uma paciente de 23 anos, natural de São Francisco-MG, que apresentava há duas semanas quadro de ceíaléia, vômitos em jato, febre e sonolência; o exame neurológico mostrava rigidez de nuca, paresia com hipertonia muscular bilateral em membros superiores, perda de motricidade e sensibilidade em membros inferiores. Não se palpava hepato-esplenomegalia. O exame do liqüido cefalorraquidiano (LCR) mostrou hipoglicorraquia (28 mg%), hiperproteinorraquia (113 mg%) e pleocitose acentuada (949 células/mm3), com predomínio de neutrófilos (70%), além de eosinofilorraquia (9%). A reação de imunofluorescência indireta para esquistossomose, no LCR, realizada em cortes de fígado com granuloma peri-ovular foi reagente (IgG: 1/16; IgM: 1/4). As pesquisas de fungos e b.a.a.r. no LCR, assim como a cultura para b.a.a.r. (após 60 dias) e as reações imunológicas para neurocisticercose foram negativas. Uma tomografia computadorizada do cérebro e medula espinhal não evidenciou anormalidades. No exame parasitologico das fezes foi identificada a presença de ovos viáveis de S. mansoni. Instituiu-se tratamento com corticóides e praziquantel (60 mg/kg/dia; 7 dias) tendo havido regressão das alterações do LCR, permanecendo entretanto seqüelas neurológicas graves (paraplegia e bexiga neurogênica)

Metabolismo de nitrogênio em dois sistemas de cultivo de café sob veranico da estação úmida

Com o objetivo de avaliar o efeito do veranico ocorrido na estação úmida sobre o metabolismo de nitrogênio em cafeeiros em sistema a pleno sol e associados com abacateiro (Persea americana Mill.) e ingazeiro (Inga edulis Mart.), foi realizado este experimento. O estudo foi conduzido em propriedade situada no município de Barra do Choça, BA, composto por plantas de café (Coffea arabica L.), variedade Catuaí, sendo caracterizados dois campos experimentais (sistema sombreado x sistema a pleno sol). As avaliações foram realizadas em janeiro (período de veranico) e março (final da estação úmida), em cinco repetições por campo experimental. Os dados foram submetidos ao teste t por meio do programa SAEG, versão 9.1. Maior teor de NO3 - foi verificado no sistema a pleno sol, tanto no período de veranico como no final da estação úmida. Em março foi observado maior acúmulo de N-orgânico no terço superior do cafeeiro a pleno sol e no terço médio do cafeeiro sombreado. Maiores teores de nitrogênio total e a tendência de maior atividade enzimática da redutase do nitrato foram verificados nos sistemas arborizados, quando avaliados dentro do mesmo terço do cafeeiro nas duas estações

Path of infectious diseases in Brazil in the last 50 years: an ongoing challenge

ABSTRACT In this article, we comment on the main features of infectious diseases in Brazil in the last 50 years, highlighting how much of this path Revista de Saúde Pública could portray. From 1967 to 2016, 1,335 articles focusing on infectious diseases were published in Revista de Saúde Pública. Although the proportion of articles on the topic have decreased from about 50.0% to 15.0%, its notability remained and reflected the growing complexity of the research required for its control. It is noteworthy that studies design and analysis strategies progressively became more sophisticated, following the great development of epidemiology in Brazil in the recent decades. Thus, the journal has followed the success of public health interventions that permitted to control or eliminate numerous infectious diseases – which were responsible, in the past, for high rates of morbidity and mortality –, and also followed the reemergence of diseases already controlled and the emergence of until then unknown diseases, with a strong impact on the Brazilian population, establishing a little predictable and very challenging path