The dermal leishmaniases of Brazil, with special reference to the eco-epidemiology of the disease in Amazonia

Six species of Leishmania are at present known to cause cutaneous and/or mucocutaneous leishamniasis in Brazil, and they are all to be found in the Amazon region of this country. The eco-epidemiology of each is discussed, with the observation that the Amazonian leishmaniases are all zoonoses, with their source in silvatic mammals and phlebotomine sandfly vectors. With man's destruction of the natural forest in southern Brazil, some sandfly species have survived by adapting to a peridomestic or domiciliary habitat in rural areas. Some domestic animals, such as dogs and equines are seemingly now involved in the epidemiology of the disease. No such process has yet been reported in the Amazon region, but may well take place with the continuing devastation of its forest.

Taxonomy of the genus Leishmania: present and future trends and their implications

The application of different taxonomic methods (Cladistic, Evolutionary Taxonomy and Numerical Taxonomy) to the taxonomy of the Genus Leishmania are reviewed. The major groupings of the most recent classifications obtained using the cladistical approach agree with the major divisions of previous classifications which used traditional taxonomy (Evolutionary Taxonomy). The advantage of the cladistical approach is that it produces cladograms whose branches indicate more accurately levels of relationships between the different taxa. Numerical Taxonomy is useful for identification but not as good as the cladistical approach for classification. The ancient division of this monophyletic genus into two major evolutionary lines supports the use of the subgeneric names Leishmania and Viannia.

A Mitochondrial DNA Phylogeny Indicates Close Relationships between Populations of Lutzomyia whitmani (Diptera: Psychodidae, Phlebotominae) from the Rain-forest Regions of Amazônia and Northeast Brazil

Phylogenetic analysis of all 31 described mitochondrial (cytochrome b) haplotypes of Lutzomyia whitmani demonstrated that new material from the State of Rondônia, in southwest Amazônia, forms a clade within a lineage found only in the rain-forest regions of Brazil. This rain-forest lineage also contains two other clades of haplotypes, one from eastern Amazônia and one from the Atlantic forest zone of northeast Brazil (including the type locality of the species in Ilhéus, State of Bahia). These findings do not favour recognizing two allopatric cryptic species of L. whitmani, one associated with the silvatic transmission of Leishmania shawi in southeast Amazônia and the other with the peridomestic transmission of Le. braziliensis in northeast Brazil. Instead, they suggest that there is (or has been in the recent past) a continuum of inter-breeding populations of L. whitmani in the rain-forest regions of Brazil.

Recent observations on the sand fly (Diptera: Psychodidae) fauna of the State of Rondônia, Western Amazônia, Brazil: the importance of Psychdopygus davisi as a vector of zoonotic cutaneous leishmaniasis

Sand flies were collected in the central region of the state of Rondônia (W 64º30' to 63º00' and S 10º00'to 11º00') using Shannon and CDC light traps from October 1997 to August 2000. A total of 85,850 specimens representing 78 named species were captured. Of these 14 were new records for Rondônia. The proportion of males/females was 1/1.131. Trypanosomatids, that are presently being identified, were detected in 11 species. Leishmania (Viannia) naiffi was recorded from Psychodopygus davisi and P. hirsutus. In the present study the dominant species was P. davisi (39.6%) followed by Lutzomyia whitmani (13.1%), P. carrerai (11.6%), and P. hirsutus (10.2%). The importance of P. davisi as a vector of zoonotic cutaneous leishmaniasis is discussed.

Nitric oxide and the resolution of inflammation: implications for atherosclerosis

The ubiquitous free radical, nitric oxide (NO), plays an important role in many biological processes including the regulation of the inflammatory response. Alterations in NO synthesis by endogenous systems likely influence inflammatory processes occurring in a wide range of diseases including many in the cardiovascular system (e.g. atherosclerosis). Progression of inflammatory conditions depends not only upon the recruitment and activation of inflammatory cells but also upon their subsequent removal from the inflammatory milieu. Apoptosis, or programmed cell death, is a fundamental process regulating inflammatory cell survival and is critically involved in ensuring the successful resolution of an inflammatory response. Apoptosis results in shutdown of secretory pathways and renders effete, but potentially highly histotoxic, cells instantly recognisable for non-inflammatory clearance by phagocytes (e.g., macrophages). However, dysregulation of apoptosis and phagocytic clearance mechanisms can have drastic consequences for development and resolution of inflammatory processes. In this review we highlight the complexities of NO-mediated regulation of inflammatory cell apoptosis and clearance by phagocytes and discuss the molecular mechanisms controlling these NO mediated effects. We believe that manipulation of pathways involving NO may have previously unrecognised therapeutic potential for limiting or resolving inflammatory and cardiovascular disease.

The leishmaniases - survival and expansion in a changing world: a mini-review

The number of cases of visceral and cutaneous leishmaniasis is increasing globally at an alarming rate irrespective of the region and the leishmaniases are amongst the top emergent diseases in spite of control measures. In the present review attention is drawn to some of the reasons for this. The leishmaniases have expanded beyond their natural ecotopes due to the ecological chaos caused by man and this in turn affects the levels of his exposure to the vectors. Examples of how different phenomana (such as war, civilian migration, immuno-suppression caused by medication and viral infections, globalization of work and leisure and transmission outside endemic areas) contribute to the spread and increase of the disease are discussed.

Should reproductively isolated populations of Lutzomyia longipalpis sensu lato receive taxonomically valid names?

A group of 18 research workers involved in different aspects of the biology of Lutzomyia longipalpis discussed whether or not it is important to give taxonomically valid names to populations that have been defined by biological, biochemical and molecular methods to be reproductively isolated. The type material of this medically important species has been lost and because of this it was recommended that a colony should be established from insects captured in the region of the type area and that their description should serve as the basis for future descriptions. It was pointed out that there is a lack of uniformity in the naming of closely related American sand flies and that some of the differences between populations of Lu. longipalpis are greater than those between accepted species. The majority of the participants agreed that the populations that have been defined in the literature as sibling species should be named.

Species diversity of sandflies (Diptera: Psychodidae) during different seasons and in different environments in the district of Taquaruçú, state of Tocantins, Brazil

Phlebotomine sandflies are the vectors for the protozoan parasites that cause leishmaniasis. The present study investigated the species composition of sandfly fauna in the rural district of Taquaruçú, municipality of Palmas, state of Tocantins, Brazil and compared the diversity of species among intradomicile, peridomicile and forest environments during the dry and rainy seasons. Sandflies were collected using CDC light traps over the course of three months during the dry and rainy seasons. A total of 767 specimens were captured, belonging to different 32 species. The most abundant species were Micropygomyia goiana (Martins, Falcão & Silva), Sciopemyia sordellii (Shannon & Del Ponte), Evandromyia carmelinoi (Ryan Fraiha, Lainson & Shaw), Evandromyia termitophila (Martins, Falcão & Silva), Nyssomyia whitmani (Antunes & Coutinho) and Lutzomyia longipalpis (Lutz & Neiva). The highest species diversity (30) and the greatest percentage of specimens (78.3%) were obtained during the rainy season. During the dry season, the species richness and abundance were greater in domestic environments. However, during the rainy season, the forest displayed the highest species richness and the domestic environment exhibited the greatest species abundance. Several important vector species are reported in this study.

The main sceneries of Chagas disease transmission. The vectors, blood and oral transmissions - A comprehensive review

This review deals with transmission ofTrypanosoma cruziby the most important domestic vectors, blood transfusion and oral intake. Among the vectors,Triatoma infestans,Panstrongylus megistus, Rhodnius prolixus,Triatoma dimidiata, Triatoma brasiliensis,Triatoma pseudomaculata, Triatoma sordida,Triatoma maculata, Panstrongylus geniculatus,Rhodnius ecuadoriensis and Rhodnius pallescens can be highlighted. Transmission of Chagas infection, which has been brought under control in some countries in South and Central America, remains a great challenge, particularly considering that many endemic countries do not have control over blood donors. Even more concerning is the case of non-endemic countries that receive thousands of migrants from endemic areas that carry Chagas disease, such as the United States of America, in North America, Spain, in Europe, Japan, in Asia, and Australia, in Oceania. In the Brazilian Amazon Region, since Shaw et al. (1969) described the first acute cases of the disease caused by oral transmission, hundreds of acute cases of the disease due to oral transmission have been described in that region, which is today considered to be endemic for oral transmission. Several other outbreaks of acute Chagas disease by oral transmission have been described in different states of Brazil and in other South American countries.

Atividade da amilase em rã-touro durante a fase pós-metamórfica

O objetivo deste trabalho foi avaliar a atividade da amilase no quimo da rã-touro, Rana catesbeiana Shaw 1802 (3,6 a 200 g). Oitenta e sete animais foram distribuídos em baias-testes com temperatura e fotoperíodo controlados. As rãs selecionadas na fase pós-metamórfica receberam ração comercial extrusada ad libitum. Durante 87 dias de experimento, foram efetuadas 29 coletas em intervalos de 1 a 8 dias. As coletas do conteúdo intestinal foram feitas mediante a insensibilização das rãs em gelo e água e isolamento posterior do intestino delgado das mesmas. Para os testes da atividade da amilase, foram utilizados kits enzimáticos comerciais. A atividade da amilase foi observada a partir do terceiro dia e apresentou aumento até alcançar estabilidade, quando os animais pesavam 4,35 g. Do sétimo dia até o final do experimento, ocorreu a manutenção da estabilidade da atividade (137,44 UI) e atividade específica da amilase (14.688 UI mg-1).

Fenologia de floração e polinização de espécies ornitófilas de bromeliáceas em uma área de campo rupestre da Chapada Diamantina, BA, Brasil

(Fenologia de floração e polinização de espécies ornitófilas de bromeliáceas em uma área de campo rupestre da Chapada Diamantina, BA, Brasil). Beija-flores são os principais polinizadores de bromeliáceas e a floração sequencial propicia a manutenção local destas aves. Neste estudo investigamos as estratégias fenológicas de floração e os visitantes florais de cinco bromeliáceas ornitófilas em uma área de campo rupestre na Chapada Diamantina, Bahia. Os dados sobre fenologia de floração foram coletados pelo acompanhamento mensal da fenofase de floração de indivíduos no período entre julho de 2006 e dezembro de 2007. Os visitantes florais foram registrados em observações naturalísticas de fevereiro de 2002 a dezembro de 2003 e de julho de 2006 a dezembro de 2007. A maioria das espécies floresceu no fim da estação seca e no início da estação chuvosa; Hohenbergia ramageana Mez apresentou floração contínua na área. A comunidade de bromélias estudada apresentou floração seqüencial e contínua, proporcionando recursos para a manutenção dos polinizadores na área ao longo do ano. Seis troquilídeos, um cerebídeo e três espécies de abelhas visitaram flores das bromélias. Chlorostilbon lucidus (Shaw, 1812), Phaethornis pretrei (Lesson & Delattre, 1839) e Coereba flaveola (Linnaeus, 1759) foram os principais polinizadores das plantas na área. Neoregelia bahiana (Ule) L. B. Sm., de corola de tubo longo é a espécie mais especializada, tendo P. pretrei como seu único polinizador, enquanto H. ramageana, com corola de tubo curto, é a mais generalista, considerada como um importante recurso para os beija-flores da área

Bancos públicos em sistemas financeiros maduros: perspectivas teóricas e desafios para os países em desenvolvimento

The paper discusses two theoretical approaches to the role of public banks (PBs): the Shaw-McKinnon model and an alternative Keynesian view. In the former, the PBs still in operation in less developing countries would be near to become fully unnecessary, in view of the advance of their financial development in the last twenty years. In the Keynesian approach this hypothesis is unlikely. Financial markets are viewed as structurally inefficient and "incomplete" for the requirements of the process of economic development. Nevertheless, it is undeniable that economic and financial development will require a definition of new strategies for PBs. The paper is concluded with a brief discussion of this issue.