T-cell responses associated with resistance to Leishmania infection in individuals from endemic areas for Leishmania (Viannia) braziliensis

Subclinical or asymptomatic infection is documented in individuals living in endemic areas for leishmaniasis suggesting that the development of an appropriate immune response can control parasite replication and maintain tissue integrity. A low morbidity indicates that intrinsic factors could favor resistance to Leishmania infection. Herein, leishmanial T-cell responses induced in subjects with low susceptibility to leishmaniasis as asymptomatic subjects were compared to those observed in cured cutaneous leishmaniasis (CCL) patients, who controlled the disease after antimonial therapy. All of them have shown maintenance of specific long-term immune responses characterized by expansion of higher proportions of CD4+ as compared to CD8+ Leishmania reactive T-lymphocytes. Asymptomatic subjects had lower indexes of in vitro Leishmania induced lymphoproliferative responses and interferon-gamma (IFN-gamma) production in comparison to CCL patients. On the other hand, interleukin (IL-10) production was much higher in asymptomatics than in CCL, while no differences in IL-5 levels were found. In conclusion, long lived T-cell responses achieved by asymptomatic individuals differed from those who had developed symptomatic leishmaniasis in terms of intensity of lymphocyte activation (proliferation or IFN-gamma) and regulatory mechanisms (IL-10). The absence of the disease in asymptomatics could be explained by their intrinsic ability to create a balance between immunoregulatory (IL-10) and effector cytokines (IFN-gamma), leading to parasite destruction without producing skin tissue damage. The establishment of profiles of cell-mediated immune responses associated with resistance against Leishmania infection is likely to make new inroads into understanding the long-lived immune protection against the disease.

Diverse population dynamics of three Anopheles species belonging to the Triannulatus Complex (Diptera: Culicidae)

The Triannulatus Complex of Anopheles (Nyssorhynchus) consists of at least three sibling species, namely Anopheles triannulatus s.s., Anopheles halophylus and a third undescribed member herein referred to as An. triannulatus "C". Sympatric anophelines belonging to species complexes, even though closely related, may exploit different environments such as larval habitats. In this paper we hypothesize that rainfall and seasonal flooding would distinctly influence the availability of larval habitats and consequently the seasonal population dynamics of sympatric members of the Triannulatus Complex. A reflection of this is distinct seasonal biting frequencies exhibited by three members of the Triannulatus Complex at a site in Central Brazil. Population dynamics seem to be influenced by the water level in the local rivers, although biting frequency of all three species was negatively influenced by rainfall. An. triannulatus s.s. was more abundant following the end of the rainy season, but notably 30 to 60 days after flooding. On the other hand, An. halophylus and An. triannulatus C peaked during the middle of the dry season, when water impoundments have no inflow, are somewhat reduced in size and the water becomes brackish. Differences in population dynamics were greater between An. triannulatus s.s. and An. halophylus and An. triannulatus C than between An. halophylus and An. triannulatus C. This might reflect differences in larval habitat exploitation and therefore spatial segregation among these members of the complex.

Prevalence of HIV type 1 drug resistance mutations in treatment-naïve and experienced patients from resource-limited settings with universal access to antiretroviral therapy: a survey in two small Brazilian cities

Concerns have been raised that universal availability of antiretroviral agents in resource-limited settings might lead to the emergence and spread of resistant strains. We present the largest survey on human immunodeficiency virus type 1 (HIV-1) resistance among treatment-naïve and experienced patients followed in small, relatively underprivileged cities in Brazil with universal availability to standard of care antiretroviral combinations. Samples were collected between 2004 and 2006 from 95 patients followed in the cities of Saquarema and Santo Antonio de Pádua, state of Rio de Janeiro. A proviral fragment encompassing protease and reverse transcriptase (RT) regions was generated and drug susceptibility level was inferred. Among 50 strains from drug-naïve subjects, one (2%) had intermediate-level resistance to RT inhibitors. Among 38 patients on therapy as of sampling, 28 (73.7%) had plasma viral load (PVL) below detection limit (26 of whom without evidence of resistance mutations) and 11 (28.9%) harbored strains with reduced susceptibility. Only two strains harbored both protease and RT inhibitor mutations. Among seven patients who were off-treatment as of sampling, two (28.5%) harbored strains with reduced susceptibility to RT inhibitors. The relatively high frequency of undetectable PVL among patients on treatment and the overall low prevalence of resistance-associated mutations are reassuring. Continued surveillance, however, is necessary.

When are we going to celebrate the centenary of the discovery of efficient treatment for congenital toxoplasmosis?

In 2008, we have celebrated the centenary of the discovery of Toxoplasma gondii.Although this ubiquitous protozoan can generate devastating damage in foetuses and newborns, its treatment is the only field in which we have made little progress, despite a huge body of research, and has not yet been validated. Pregnant women who seroconvert are generally given spiramycine in order to reduce the risk of vertical transmission. However, to date, we have no evidence of the efficacy of this treatment because no randomized controlled trials have as yet been conducted. When foetal contamination is demonstrated, pyrimethamine, in association with sulfadoxine or sulfadiazine, is normally prescribed, but the effectiveness of this treatment remains to be shown. With regard to postnatal treatment, opinions vary considerably in terms of drugs, regimens and length of therapy. Similarly, we do not have clear evidence to support routine antibiotic treatment of acute ocular toxoplasmosis. We must be aware that pregnant women and newborns are currently being given empirically potentially toxic drugs that have no proven benefit. We must make progress in this field through well-designed collaborative studies and by drawing the attention of policy makers to this disastrous and unsustainable situation.

Back to the future in Chagas disease: from animal models to patient cohort studies, progress in immunopathogenesis research

Despite the wealth of information generated by trans-disciplinary research in Chagas disease, knowledge about its multifaceted pathogenesis is still fragmented. Here we review the body of experimental studies in animal models supporting the concept that persistent infection by Trypanosoma cruzi is crucial for the development of chronic myocarditis. Complementing this review, we will make an effort to reconcile seemingly contradictory results concerning the immune profiles of chronic patients from Argentina and Brazil. Finally, we will review the results of molecular studies suggesting that parasite-induced inflammation and tissue damage is, at least in part, mediated by the activities of trans-sialidase, mucin-linked lipid anchors (TLR2 ligand) and cruzipain (a kinin-releasing cysteine protease). One hundred years after the discovery of Chagas disease, it is reassuring that basic and clinical research tends to converge, raising new perspectives for the treatment of chronic Chagas disease.

The contributions of the Genome Project to the study of schistosomiasis

In this paper we review the impact that the availability of the Schistosoma mansoni genome sequence and annotation has had on schistosomiasis research. Easy access to the genomic information is important and several types of data are currently being integrated, such as proteomics, microarray and polymorphic loci. Access to the genome annotation and powerful means of extracting information are major resources to the research community.

Instrument for assessing the quality of mobile emergency pre-hospital care: content validation

OBJECTIVES To validate an instrument to assess quality of mobile emergency pre-hospital care. METHOD A methodological study where 20 professionals gave their opinions on the items of the proposed instrument. The analysis was performed using Kappa test (K) and Content Validity Index (CVI), considering K> 0.80 and CVI ≥ 0.80. RESULTS Three items were excluded from the instrument: Professional Compensation; Job Satisfaction and Services Performed. Items that obtained adequate K and CVI indexes and remained in the instrument were: ambulance conservation status; physical structure; comfort in the ambulance; availability of material resources; user/staff safety; continuous learning; safety demonstrated by the team; access; welcoming; humanization; response time; costumer privacy; guidelines on care; relationship between professionals and costumers; opportunity for costumers to make complaints and multiprofessional conjunction/actuation. CONCLUSION The instrument to assess quality of care has been validated and may contribute to the evaluation of pre-hospital care in mobile emergency services.

Factors influencing adherence to standard precautions among nursing professionals in psychiatric hospitals

OBJECTIVE Evaluate and correlate individual, work-related and organizational factors that influence adherence to standard precautions among nursing professionals of psychiatric hospitals in São Paulo. METHOD An exploratory cross-sectional study conducted with 35 nursing professionals, using the assessment tool for adherence to standard precautions through the Likert scale, ranging from 1 to 5. RESULTS Knowledge of the precautions received a high score (4.69); adherence received (3.86) and obstacles (3.78), while intermediaries and the scales of organizational factors received low scores (2.61). There was a strong correlation between the magnitude adherence scale and the personal protective equipment availability (r = 0.643; p = 0.000). The training scale for prevention of HIV exposure (p = 0.007) was statistically different between the nurses and nursing assistants. CONCLUSION The organizational factors negatively contributed to adherence to standard precautions, indicating that psychiatric institutions lack safe working conditions, ongoing training and management actions to control infections.

Odontopus brevirostris (Hustache, 1936) (Coleoptera, Curculionidae) associated with new host plants belonging to Annona (Annonaceae)

Odontopus brevirostris (Hustache, 1936) feeding on Annona squamosa L., A. cherimola Mill., A. glabra L., and A. muricata L. was observed. The last three host plants are recorded for the first time. The endophitic oviposition occurs in the veins of the ventral surface of the young leaves. The larvae, leaf miners, eat the parenchyma and the adults make small holes in the leaves. The pupation occurs in spherical cocoons protected by a sort of nest (pupation chamber) between the two epidermal layers.

Taxonomy and morphology of Apsil Malloch (Diptera, Muscidae, Coenosiinae, Coenosiini) with new records, description of a new species and a key to identification

Taxonomy and morphology of Apsil Malloch (Diptera, Muscidae, Coenosiinae, Coenosiini) with new records, description of a new species and a key to identification. Apsil Malloch (Diptera, Muscidae, Coenosiinae, Coenosiini) includes 10 species, most of them described from Chile, but some also from Argentina. Five of them and one new species were found at the California Academy of Sciences collection (San Francisco, California) during the course of a project developed in that institution. Almost all material studied was collected in Chile, mainly by M. E. Irwin, during the year of 1966. Brief diagnosis of the known studied species (A. apicata Malloch, A. atripes Malloch, A. dilata Malloch, A. maculiventris Malloch (female described for the first time) and A. spatulata, Malloch), the description of A. mallochi, sp. nov. and a key for the identification of all known species are given. Color illustrations of some morphological characters make easier the recognition of the species. New geographic records were assigned.

Harmonia axyridis: a threat to Brazilian Coccinellidae?

Harmonia axyridis (Pallas) (Coleoptera, Coccinellidae) is a polyphagous Asian species, well-known as a classical biological control agent of aphids around the world, introduced probably accidentally in Brazil, sampled for the first time in 2002. It is an important intraguild predator, competing for food with native coccinellids. It was studied H. axyridis alimentary sources and host plants, its abundance compared with native and established species, the influence of abiotic factors and the seasons over the abundance of H. axyridis throughout one year, and discussed the mechanisms which influence the displacement of species. Harmonia axyridis was found in 38 plant species, among them 20 were new records, feeding on 20 aphid species, eight of them new alimentary records. Between 2006/2007, eight Coccinellidae species were collected and H. axyridis was the most abundant (91.23%). Harmonia axyridis peak of abundance occurred in August and September 2007, probably influenced by the temperature and food availability. From 1999 to 2007 a reduction and variation in the diversity of collected species of Coccinellidae were observed with the predominance of H. axyridis, which may indicate their displacement.

Will the Convention on Biological Diversity put an end to biological control?

Will the Convention on Biological Diversity put an end to biological control? Under the Convention on Biological Diversity countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties. This also applies to species collected for potential use in biological control. Recent applications of access and benefit sharing principles have already made it difficult or impossible to collect and export natural enemies for biological control research in several countries. If such an approach is widely applied it would impede this very successful and environmentally safe pest management method based on the use of biological diversity. The International Organization for Biological Control of Noxious Animals and Plants has, therefore, created the "Commission on Biological Control and Access and Benefit Sharing". This commission is carrying out national and international activities to make clear how a benefit sharing regime might seriously frustrate the future of biological control. In addition, the IOBC Commission members published information on current regulations and perceptions concerning exploration for natural enemies and drafted some 30 case studies selected to illustrate a variety of points relevant to access and benefit sharing. In this article, we summarize our concern about the effects of access and benefit sharing systems on the future of biological control.

On the nesting biology of Pirhosigma Giordani Soika (Hymenoptera, Vespidae, Eumeninae), with special reference to the use of vegetable matter

On the nesting biology of Pirhosigma Giordani Soika (Hymenoptera, Vespidae, Eumeninae), with special reference to the use of vegetable matter. The use of vegetable matter in nest building is not widespread among the Eumeninae, and is reported for the first time for the two species of potter wasps Pirhosigma superficiale and P. limpidum. These wasps make mostly spherical mud nests over which they attach small pieces of unmasticated plant matter. Use of plant fragments in this group of wasps is interpreted as camouflage behavior.

Nest plasticity of Cornitermes silvestrii (Isoptera, Termitidae, Syntermitinae) in response to flood pulse in the Pantanal, Mato Grosso, Brazil

Nest plasticity of Cornitermes silvestrii (Isoptera, Termitidae, Syntermitinae) in response to flood pulse in the Pantanal, Mato Grosso, Brazil. The Pantanal is one of the largest wetlands in the world. Since many areas in Pantanal are flooded during part of the year, it is expected that plants and animals would have mechanisms for their survival during the flooded period. This study investigated the existence of differences in nest shape and inquilines of Cornitermes silvestrii in areas influenced by the flood pulse. We measured the volume, height, width, and height/width ratio of 32 nests in flooded areas and 27 in dry areas, and performed an one-way-Anova with the quasi-Poisson distribution to determine if there were differences in the nest measurements between the points. To analyze the relationship of nest inquilines to flood pulse and nest shape, we performed a regression with a Poisson distribution with the inquiline richness and flood pulse, and the above measurements. The nests of C. silvestrii in flooded areas were significantly higher than nests in dry areas, and had a larger height/width ratio. Colonies in periodically flooded areas would probably make a larger effort to extend their nests vertically, to maintain at least some portion of the structure out of the water and prevent the entire colony from being submerged. Neither the size of the nest nor the flood pulses influenced the assemblage of 11 species found in nests of C. silvestrii.

Spatial and temporal dynamics of drosophilid larval assemblages associated to fruits

The study of organisms and their resources is critical to further understanding population dynamics in space and time. Although drosophilids have been widely used as biological models, their relationship with breeding and feeding sites has received little attention. Here, we investigate drosophilids breeding in fruits in the Brazilian Savanna, in two contrasting vegetation types, throughout 16 months. Specifically, larval assemblages were compared between savannas and forests, as well as between rainy and dry seasons. The relationships between resource availability and drosophilid abundance and richness were also tested. The community (4,022 drosophilids of 23 species and 2,496 fruits of 57 plant taxa) varied widely in space and time. Drosophilid assemblages experienced a strong bottleneck during the dry season, decreasing to only 0.5% of the abundance of the rainy season. Additionally, savannas displayed lower richness and higher abundance than the forests, and were dominated by exotic species. Both differences in larval assemblages throughout the year and between savannas and gallery forests are consistent with those previously seen in adults. Although the causes of this dynamic are clearly multifactorial, resource availability (richness and abundance of rotten fruits) was a good predictor of the fly assemblage structure.