Comparative immunological recognition of proteins from New Guinea "C" dengue virus type 2 prototype and from a dengue virus type 2 strain isolated in the State of Rio de Janeiro, Brazil

The protein profiles of the New Guinea "C" dengue virus type 2 (DENV-2)prototype and those of a Brazilian DENV-2 isolated in the State of Rio de Janeiro in 1995 were compared. SDS-PAGE analysis showed that the virus from Rio de Janeiro expresses NS5 (93.0 kDa), NS3 (66.8 kDa) E (62.4 kDa) and NS1 (41.2 kDa) proteins differently from the New Guinea "C" virus. The immunoblot revealed specificity and antigenicity for the NS3 protein from DENV-2 Rio de Janeiro mainly in primary infections, convalescent cases, and in secondary infections in both cases and only antigenicity for E and NS1 proteins for both viruses in primary and secondary infections.

Comparative recognition by human IgG antibodies of recombinant proteins representing three asexual erythrocytic stage vaccine candidates of Plasmodium vivax

In previous immuno-epidemiological studies of the naturally acquired antibody responses to merozoite surface protein-1 (MSP-1) of Plasmodium vivax, we had evidence that the responses to distinct erythrocytic stage antigens could be differentially regulated. The present study was designed to compare the antibody response to three asexual erythrocytic stage antigens vaccine candidates of P. vivax. Recombinant proteins representing the 19 kDa C-terminal region of MSP-1(PvMSP19), apical membrane antigen n-1 ectodomain (PvAMA-1), and the region II of duffy binding protein (PvDBP-RII) were compared in their ability to bind to IgG antibodies of serum samples collected from 220 individuals from the state of Pará, in the North of Brazil. During patent infection with P. vivax, the frequency of individuals with IgG antibodies to PvMSP1(19), PvAMA-1, and PvDBP-RII were 95, 72.7, and 44.5% respectively. Although the frequency of responders to PvDBP-RII was lower, this frequency increased in individuals following multiple malarial infections. Individually, the specific antibody levels did not decline significantly nine months after treatment, except to PvMSP1(19). Our results further confirm a complex regulation of the immune response to distinct blood stage antigens. The reason for that is presently unknown but it may contribute to the high risk of re-infection in individuals living in the endemic areas.

Recognition of the epidemiological significance of Neisseria meningitidis capsular serogroup W135 in the Rio de Janeiro region, Brazil

Neisseria meningitidis retains its ability to cause endemic and hiperendemic disease in human population living in any environment, as well as localized outbreaks and massive epidemics in civilians and military personnel. In Rio de Janeiro it has been reported in the 1990s as prolonged outbreak of serogroup B and at least one epidemic of serogroup C was well defined, both demanding quick action by the Public Health authorities. We report here the emergence of serogroup W135 meningococcal disease causing endemic and case cluster in Rio de Janeiro during the first years of this new century.

RNA polymerase I promoter and splice acceptor site recognition affect gene expression in non-pathogenic Leishmania species

Leishmania (Sauroleishmania) tarentolae has biotechnological potential for use as live vaccine against visceral leishmaniasis and as a system for the over expression of eukaryotic proteins that possess accurate post-translational modifications. For both purposes, new systems for protein expression in this non-pathogenic protozoan are necessary. The ribosomal RNA promoter proved to be a stronger transcription driver since its use yielded increased levels of recombinant protein in organisms of both genera Trypanosoma or Leishmania. We have evaluated heterologous expression systems using vectors with two different polypyrimidine tracts in the splice acceptor site by measuring a reporter gene transcribed from L. tarentolae RNA polymerase I promoter. Our data indicate that the efficiency of chloramphenicol acetyl transferase expression changed drastically with homologous or heterologous sequences, depending on the polypyrimidine tract used in the construct and differences in size and/or distance from the AG dinucleotide. In relation to the promoter sequence the reporter expression was higher in heterologous lizard-infecting species than in the homologous L. tarentolae or in the mammalian-infecting L. (Leishmania) amazonensis.

The Anopheles albitarsis complex with the recognition of Anopheles oryzalimnetes Wilkerson and Motoki, n. sp. and Anopheles janconnae Wilkerson and Sallum, n. sp. (Diptera: Culicidae)

The Anopheles (Nyssorhynchus) albitarsis complex includes six species: An. albitarsis, Anopheles oryzalimnetes Wilkerson and Motoki, n. sp., Anopheles marajoara, Anopheles deaneorum, Anopheles janconnae Wilkerson and Sallum, n. sp. and An. albitarsis F. Except for An. deaneorum, species of the complex are indistinguishable when only using morphology. The problematic distinction among species of the complex has made study of malaria transmission and ecology of An. albitarsis s.l. difficult. Consequently, involvement of species of the An. albitarsis complex in human Plasmodium transmission is not clear throughout its distribution range. With the aim of clarifying the taxonomy of the above species, with the exception of An. albitarsis F, we present comparative morphological and morphometric analyses, morphological redescriptions of three species and description of two new species using individuals from populations in Brazil, Paraguay, Argentina and Venezuela. The study included characters from adult females, males, fourth-instar larvae, pupae and male genitalia of An. albitarsis, An. marajoara, An. deaneorum and An. oryzalimnetes n. sp. For An. janconnae n. sp. only characters of the female, male and male genitalia were analyzed. Fourth-instar larvae, pupae and male genitalia characteristics of all five species are illustrated. Bionomics and distribution data are given based on published literature records.

Participation of N-acetyl-D-glucosamine carbohydrate moieties in the recognition of Schistosoma mansoni sporocysts by haemocytes of Biomphalaria tenagophila

Lectin-carbohydrate binding may be involved in the recognition of Schistosoma mansoni sporocysts by haemocytes of Biomphalaria; therefore, we tested if this interaction is associated with snail resistance against Schistosoma infection. In vitro data showed that most of the S. mansoni sporocysts cultured with haemocytes from Biomphalaria glabrata BH, a highly susceptible snail strain, had a low number of cells that adhered to their tegument and a low mortality rate. Moreover, the addition of N-acetyl-D-glucosamine (GlcNAc) did not alter this pattern of adherence and mortality. Using haemocytes and haemolymph of Biomphalaria tenagophila Cabo Frio, we observed a high percentage of sporocysts with adherent cells, but complete encapsulation was not detected. Low concentrations of GlcNAc increased haemocyte binding to the sporocysts and mortality, which returned to basal levels with high concentrations of the carbohydrate. In contrast, haemocytes plus haemolymph from B. tenagophila Taim encapsulated cellular adhesion index of level 3 and destroyed over 30% of the S. mansoni sporocysts in culture. Interestingly, the addition of GlcNAc, but not mannose, to the culture medium resulted in the significant inhibition of cellular adhesion to the parasite tegument and the reduction of parasite mortality, suggesting that GlcNAc carbohydrate moieties are important to the recognition of S. mansoni by B. tenagophila Taim.

Recognition of enteroinvasive Escherichia coli and Shigella flexneri by dendritic cells: distinct dendritic cell activation states

The innate and adaptive immune responses of dendritic cells (DCs) to enteroinvasive Escherichia coli (EIEC) infection were compared with DC responses to Shigella flexneri infection. EIEC triggered DCs to produce interleukin (IL)-10, IL-12 and tumour necrosis factor (TNF)-α, whereas S. flexneri induced only the production of TNF-α. Unlike S. flexneri, EIEC strongly increased the expression of toll like receptor (TLR)-4 and TLR-5 in DCs and diminished the expression of co-stimulatory molecules that may cooperate to inhibit CD4+ T-lymphocyte proliferation. The inflammation elicited by EIEC seems to be related to innate immunity both because of the aforementioned results and because only EIEC were able to stimulate DC transmigration across polarised Caco-2 cell monolayers, a mechanism likely to be associated with the secretion of CC chemokine ligands (CCL)20 and TNF-α. Understanding intestinal DC biology is critical to unravelling the infection strategies of EIEC and may aid in the design of treatments for infectious diseases.

Expression of non-TLR pattern recognition receptors in the spleen of BALB/c mice infected with Plasmodium yoelii and Plasmodium chabaudi chabaudi AS

The spleen plays a crucial role in the development of immunity to malaria, but the role of pattern recognition receptors (PRRs) in splenic effector cells during malaria infection is poorly understood. In the present study, we analysed the expression of selected PRRs in splenic effector cells from BALB/c mice infected with the lethal and non-lethal Plasmodium yoelii strains 17XL and 17X, respectively, and the non-lethal Plasmodium chabaudi chabaudi AS strain. The results of these experiments showed fewer significant changes in the expression of PRRs in AS-infected mice than in 17X and 17XL-infected mice. Mannose receptor C type 2 (MRC2) expression increased with parasitemia, whereas Toll-like receptors and sialoadhesin (Sn) decreased in mice infected with P. chabaudi AS. In contrast, MRC type 1 (MRC1), MRC2 and EGF-like module containing mucin-like hormone receptor-like sequence 1 (F4/80) expression decreased with parasitemia in mice infected with 17X, whereas MRC1 an MRC2 increased and F4/80 decreased in mice infected with 17XL. Furthermore, macrophage receptor with collagenous structure and CD68 declined rapidly after initial parasitemia. SIGNR1 and Sn expression demonstrated minor variations in the spleens of mice infected with either strain. Notably, macrophage scavenger receptor (Msr1) and dendritic cell-associated C-type lectin 2 expression increased at both the transcript and protein levels in 17XL-infected mice with 50% parasitemia. Furthermore, the increased lethality of 17X infection in Msr1 -/- mice demonstrated a protective role for Msr1. Our results suggest a dual role for these receptors in parasite clearance and protection in 17X infection and lethality in 17XL infection.

Antibody recognition of Plasmodium falciparum infected red blood cells by symptomatic and asymptomatic individuals in the Brazilian Amazon

In the Amazon Region, there is a virtual absence of severe malaria and few fatal cases of naturally occurring Plasmodium falciparum infections; this presents an intriguing and underexplored area of research. In addition to the rapid access of infected persons to effective treatment, one cause of this phenomenon might be the recognition of cytoadherent variant proteins on the infected red blood cell (IRBC) surface, including the var gene encoded P. falciparum erythrocyte membrane protein 1. In order to establish a link between cytoadherence, IRBC surface antibody recognition and the presence or absence of malaria symptoms, we phenotype-selected four Amazonian P. falciparum isolates and the laboratory strain 3D7 for their cytoadherence to CD36 and ICAM1 expressed on CHO cells. We then mapped the dominantly expressed var transcripts and tested whether antibodies from symptomatic or asymptomatic infections showed a differential recognition of the IRBC surface. As controls, the 3D7 lineages expressing severe disease-associated phenotypes were used. We showed that there was no profound difference between the frequency and intensity of antibody recognition of the IRBC-exposed P. falciparum proteins in symptomatic vs. asymptomatic infections. The 3D7 lineages, which expressed severe malaria-associated phenotypes, were strongly recognised by most, but not all plasmas, meaning that the recognition of these phenotypes is frequent in asymptomatic carriers, but is not necessarily a prerequisite to staying free of symptoms.

Etnografia: esteatégia metodológica utilizada para contextualizar o cenário cultural do CTI de um hospital universitário

O presente trabalho é parte de um estudo etnográfico realizado em um CTI de um hospital universitário que teve o objetivo de descrever a cultura dos intensivistas. São apresentados domínios e taxonomias culturais elaborados a partir dos relatos dos intensivistas. Os resultados aqui apresentados demostraram que a etnografia é uma estratégia metodológica adequada para contextualização do cenário cultural sob o ponto de vista de quem vivencia o cotidiano do trabalho na terapia intensiva.

O processo de cuidar da pessoa que sofreu queimaduras: significado cultural atribuído por familiares

Os objetivos deste estudo etnográfico foram identificar o significado cultural atribuído por familiares à participação no processo de cuidar da pessoa ultima de queimadura; identificar as estratégias de cuidado que os familiares focalizam frente à participação no cuidado. Os dados foram coletados mediante entrevistas semi-estruturadas com 25 familiares de clientes que sofreram queimaduras, admitidos em uma Unidade de Queimados e observações participantes. Os resultados mostram que o significado cultural atribuído por familiares de pessoas vítimas queimaduras ao processo de cuidar tem duas dimensões: a física e a moral e gera principalmente medo.

A sexualidade como uma construção cultural: reflexões sobre preconceitos e mitos inerentes a um grupo de mulheres rurais

Este artigo apresenta a sexualidade como uma construção cultural. Para fundamentar tal assertiva, é relatada uma pesquisa realizada com um grupo de onze mulheres de uma comunidade rural, no interior do Rio Grande do Sul. Os dados foram coletados por meio de entrevistas semi-estruturadas e as narrativas foram analisadas qualitativamente, buscando, via ótica cultural, o significado dos depoimentos. A sexualidade é, aqui, contemplada a partir das vivências individuais, dos valores, das crenças, dos mitos e dos preconceitos, construídos ao longo da socialização de cada colaboradora. No final do texto, foram acrescentadas algumas reflexões que salientam a importância de tal interpretação cultural sobre os eventos, especialmente sobre a sexualidade para as enfermeiras.

Adaptação cultural e validação do instrumento demandas de atenção dirigida

Este estudo tem como objetivos traduzir e validar o instrumento Requirement for Directed Attention (RDA), desenvolvido por Guirardello, para a cultura brasileira. É um instrumento composto de 39 itens que aborda situações no ambiente de trabalho de unidades de cuidados críticos e médico-cirúrgica que demandam atenção dirigida do enfermeiro. O procedimento metodológico constituiu nas etapas de: a) tradução do instrumento para a língua portuguesa; b) back-translation; c) avaliação por um grupo de juízes e d) pré-teste da versão final do instrumento. O instrumento na versão em Português foi aplicado a um grupo de 44 enfermeiros. Os dados resultaram em alta consistência interna para o total dos itens (a = 0,91) e para os domínios: Ambiente Físico (a = 0,78), Psicológico (a = 0,85) e Comportamental (a = 0,80). Apenas o domínio Informação obteve um a de 0,12. Esses resultados sugerem que a versão em Português do RDA pode ser usada para avaliar as demandas de atenção do enfermeiro.

O conflito como realidade e desafio cultural no exercício da gerência do enfermeiro

O exercício da gerência do enfermeiro é permeado de conflitos que podem ser interpretados pelos referenciais de cultura. O presente estudo tem como objetivo denotar especificidades culturais, analisadas segundo a Teoria Interpretativa da Cultura de Geertz, que se expressam como conflitos no âmbito da gerência do enfermeiro num Hospital Universitário. Os resultados denotam a incorporação de elementos ideológicos e de mecanismos de controle e de poder, que manifestam sua origem na forma de organização do trabalho. Percebe-se a efetivação de políticas alicerçadas em valores da própria profissão. As práticas exercidas destacam uma construção cultural que elucida algumas compreensões dos processos cognitivos, sociais e comportamentais, pois estes organizam as interpretações e as respostas para os eventos da prática gerencial do enfermeiro. Os resultados deste estudo apontam para a importância da cultura organizacional no exercício da gerência na enfermagem diante das incertezas laborais, na complexidade do ambiente hospitalar

Conhecimento e significado cultural da menopausa para um grupo de mulheres

Este estudo etnográfico, realizado junto a um grupo de mulheres, teve como objetivo verificar o nível de conhecimento sobre a menopausa e compreender como ocorre a vivência deste estágio biológico próprio do sexo feminino. Para a coleta dos dados, usou-se a observação participante, a entrevista, mediante uso de gravador, além de desenhos previamente reproduzidos. A análise foi efetuada com base nos pressupostos teóricos, de método etnográfico e de alguns pressupostos do interpretativismo biográfico. Das narrativas coletadas, extraíram-se as categorias e os temas culturais. Assim, foi possível verificar que o processo da menopausa era entendido como resultante de uma construção singular, estando integrado a uma rede de significados, instituídos pelo grupo, os quais condicionam o conhecimento e a vivência dentro de determinados padrões culturais, entre eles, o fato de que a menopausa significa deixar de ser mulher.