A Natural Protective Mechanism Against Malaria

Malaria is an infectious disease of humans and other animals including birds, reptiles and most mammals. It is transmitted via the inoculation of Plasmodium sporozoites into the skin through the bite of an infected female Anopheles mosquito. Although every year, around 700.000 lives are perished, mainly children under the age of 3-5 years old, to Plasmodium infection this deadly parasite has a relatively low efficiency of transmission from mosquitoes into humans.(...)

Fauna of Culicidae in rural areas of Porto Velho and the first record of Mansonia (Mansonia) flaveola (Coquillet, 1906), for the state of Rondônia, Brazil

INTRODUCTION: Knowledge concerning the fauna of Culicidae in the Brazilian Amazon States contributes to current understanding of the bionomics of the insects collected and makes it possible to observe changes in the fauna over time. METHODS: The Culicidae were captured with a BG-Sentinel® trap in extra-domiciliary area of two rural regions of Porto Velho in June and July of 2007 and 2008. RESULTS: A total of 10,695 Culicidae was collected, belonging to nine genera: Coquillettidia, Culex, Mansonia, Psorophora, Aedes, Aedeomyia, Anopheles, Uranotaenia and Wyeomyia. CONCLUSIONS: The presence of Mansonia (Mansonia) flaveola was recorded in the State of Rondônia for the first time.

Evaluation of larvicidal activity and brine shrimp toxicity of rhizome extracts of Zingiber zerumbet (L.) Smith

Introduction In this study, we used dichloromethane (DCM) and methanol (MeOH) extracts of the Zingiber zerumbet rhizome to evaluate brine shrimp lethality and larvicidal activity on Aedes aegypti and Anopheles nuneztovari mosquitoes. Methods Bioassays were performed by exposing third-instar larvae of each mosquito species to the DCM or MeOH extracts. Results Probit analysis with DCM and MeOH extracts demonstrated efficient larvicidal activity against A. aegypti and A. nuneztovari larvae. Conclusions The DCM and MeOH extracts showed higher activity against A. nuneztovari larvae than against A. aegypti larvae, suggesting that the extracts have species-specific activity.

Immature mosquitoes (Diptera: Culicidae) in a eutrophic landfill tank from State of Rio de Janeiro, Brazil

Introduction To determine the faunal composition of immature culicids inhabiting a percolation tank in the landfill of Sapucaia, State of Rio de Janeiro, Brazil, immature mosquitoes were collected over a two-day period during the third weeks of April, August and October 2011. Results The species found were Culex usquatus, Lutzia bigoti, Anopheles argyritarsis and Limatus durhamii. This study is the first to report the colonization of eutrophic breeding sites by these species. Conclusions The oviposition behavior observed in this study suggests a secondary adaptation or change in habit to select eutrophic environments during the developmental stages of the observed species.

The influence of the area of the Serra da Mesa Hydroelectric Plant, State of Goiás, on the frequency and diversity of anophelines (Diptera: Culicidae): a study on the effect of a reservoir

INTRODUCTION: Bioecological aspects of anophelines (Diptera: Culicidae) near areas under the direct influence of the hydroelectric plant reservoir of Serra da Mesa in Goiás, Brazil, were analyzed. METHODS: Samples were collected at the surrounding dam area during the phases before and after reservoir impoundment. The influence of climatic and environmental factors on the occurrence of Anopheles darlingi, Anopheles albitarsis, Anopheles triannulatus, Anopheles oswaldoi and Anopheles evansae was assessed using Pearson's correlations with indicators for richness and diversity as well as the index of species abundance (ISA) and the standardized index of species abundance (SISA). RESULTS: The highest anopheline density occurred during the phase after filling the tank; however, no direct correlation with the climatic factors was observed during this stage. The reservoir formation determined the incidence of the anopheline species. An. darlingi was the predominant species (SISA = 1.00). CONCLUSIONS: The significant difference (p < 0.05) observed between the species incidence during the different reservoir phases demonstrates the environmental effect of the reservoir on anophelines.

Desenvolvimento de um teste de diagnóstico rápido para a deteção de malária em amostras clínicas

A malária é uma doença infeciosa transmitida através da picada de um mosquito fêmea Anopheles infetado com o parasita protozoário do género Plasmodium (P.), sendo o P. falciparum a espécie mais mortal. É responsável pela morte de milhares de pessoas por ano, nomeadamente nos países em vias desenvolvimento, países esses que não detêm as condições necessárias para a prática da microscopia ótica em larga escala, que continua nos dias de hoje a ser a técnica de eleição para o diagnóstico da doença. A conceção de testes de baixo custo e de fácil utilização tais como os testes de diagnóstico rápido (TDR) são uma mais-valia no diagnóstico deste tipo de doenças. A presente dissertação centra-se no desenvolvimento de um TDR num formato competitivo, baseado em nanopartículas de ouro (AuNP) funcionalizadas com ácido mercaptoundecanoico (MUA) ou com o pentapétido Cys-Ala-Leu-Asn-Asn (CALNN) e conjugadas com um anticorpo monoclonal anti-PfHRP2 que reconhece especificamente a proteína rica em histidina 2 produzida pelo P. falciparum (PfHRP2). Para isso, utilizou-se uma tecnologia inovadora na conceção do TDR, a tecnologia lab on paper, que utiliza o papel Whatman nº1. Os estudos de estabilidade de AuNP funcionalizadas com citrato de sódio, MUA ou CALNN por variação da força iónica e pH do meio mostraram que o pentapéptido CALNN é o agente de revestimento mais resistente a oscilações de força iónica, comparativamente com o citrato de sódio e o MUA e que apenas as AuNP revestidas com citrato de sódio atingiram o ponto de agregação ao pKa da molécula de revestimento. Os principais resultados obtidos aquando do desenvolvimento do TDR revelaram que o valor de diluição ótima de anticorpo anti-IgG (solução mãe a 11 mg.mL-1) imobilizado na linha de controlo é de 1:40 e 1:90, utilizando para deteção os bionanoconjugados AuNP-MUA-Anticorpo e AuNP-CALNN-Anticorpo, respetivamente. Com a aplicação da solução AuNP-CALNN-Anticorpo visualizou-se o aparecimento de cor vermelha na linha de teste, o que demonstra a deteção do antigénio pelos bionanoconjugados. A deteção ocorreu com a aplicação de 2,5 μL de PfHRP2 a 1,5 mg.mL-1. Numa análise global após a aplicação de culturas de sangue não infetadas ou infetadas com o parasita da malária, obteve-se cor na linha de controlo com uma diluição de 1:20 do anticorpo anti-IgG imobilizado. Em relação à linha de teste, na presença de culturas não infetadas, obteve-se sinal na mesma aplicando bionanoconjugados AuNP-MUA-Anticorpo e 2,5 μL de PfHRP2 a 2,6 mg.ml-1.

Mediadores Pró-inflamatórios como factores preditivos de malária grave em crianças

A malária é uma doença potencialmente fatal, causada pelo parasita Plasmodium e transmitida ao ser humano pela picada do mosquito Anopheles, sendo endémica em 106 países, principalmente dos trópicos. É responsável por uma grande mortalidade e morbilidade em termos globais, principalmente em crianças com menos de cinco anos, continuando por esclarecer muitos dos mecanismos que contribuem para o seu espectro de gravidade. O presente trabalho teve como objectivo geral o estudo do perfil de mediadores pró-inflamatórios como possíveis factores preditivos de malária grave, definida pelos critérios da OMS, numa amostra de crianças da vila de Bor, na Guiné-Bissau. Procedeu-se à determinação dos níveis de anticorpos totais e IgG e IgM anti- P. falciparum, determinação dos níveis de óxido nítrico (NO) e estudo do processo de activação do sistema complemento pela determinação dos níveis de anafilatoxina C5a e proteína C reactiva (CRP). Cumpriram os critérios iniciais de inclusão no estudo, treze crianças, tendo para a fase final do mesmo, sido considerados doze crianças, com uma mediana de idades de cinco anos, oriundos na sua maioria de famílias com baixo nível socioeconómico. As principais manifestações clínicas de malária grave foram a prostração, icterícia e a dispneia e todas as crianças foram tratadas com quinino endovenoso. Verificou-se um óbito. Nesta amostra de doentes, observou-se na maioria dos casos, um aumento dos mediadores inflamatórios doseados, nomeadamente as IgGs totais, IgG e IgM anti- P. falciparum, CRP, C5a e NO. Apesar do reduzido tamanho da amostra, pretendeu-se com este estudo contribuir para uma melhor compreensão dos mecanismos fisiopatológicos e clínicos da malária grave em crianças de uma zona endémica como é a Guiné-Bissau.

ELECTROPHORETIC ANALYSIS OF 11 ENZYMES IN NATURAL POPULATIONS OFROOT, 1926 (DIPTERA: CULICIDAE) IN THE AMAZON REGION

Of eleven proteins analyzed in four Amazonian populations, the esterases showed the greatest variation, with five activity zones. EST1, EST2 and EST5 showed variation in each of the populations studied. EST1 and EST2 are each controlled by two, and EST5 by four, codomi-nant alleles. LAP presented six activity zones, with codominant variation in LAP5and LAP6.oc—GPDH was monomorphic with one activity band on starch gel and two on polyacrylamide gel. 1DH presented two activity zones, with variation in the IDHl region. PGM had a single activity zone, with variation in all populations. The Ariquemes populations showed five alleles and the other populations three, all of then codominant. Three activity zones with two codominant alleles were observed for ODH. Aldehyde Oxidase showed two activity zones, with variation in AOl only in the Ariquemes and Porto Velho/Samuel populations. 6-PGDH showed only one activity zone and variation only in the Ariquemes population. The remaing systems - XDH, G-6-PDH and GDH. was monomorphic.

Culicidae (Diptera: Culicomorpha) da Amazônia Ocidental Brasileira: Querari

Foram coletados adultos e imaturos de Culicidae (Diptera: Culicomorpha) em Querari, Município de São Gabriel da Cachoeira, Estado do Amazonas. Brasil. Os adultos foram capturados utilizando armadilhas (CDC e Malaise) e com puçá (varredura). Os imaturos foram coletados em poças de água (no solo e em pedras) e nas axilas de bromélias epífitas e terrestres. Apresenta-se uma lista das espécies da família Culicidae, incluindo 42 novos registros de distribuição para a região. As espécies encontradas pertencem aos gêneros Ochlerotatus, Anopheles, Coquillettidia, Culex, Haemagogus, Johnbelkinia, Limatus, Psorophora, Sabethes, Trichoprosopon, Uranotaenia e Wyeomyia.

Estudo de anofelinos antropofílicos peridomiciliares da Praia da Saudade na Ilha de Cotijuba: uma área endêmica de malária em Belém, Pará

Apesar da sua localização perto de Belém, Pará, a Ilha de Cotijuba tem sido assolada por surtos de malária durante os últimos anos, principalmente nos meses de abril a maio. A ilha faz parte de um arquipélago situado às margens da baía do Marajó, a 29 km de Belém, constituindo uma parte insular dessa cidade. Cotijuba possui uma área de cerca de 60 km² e uma costa com 20 km de praias, que corresponde a 66% da área total da ilha. Por causa das repetidas epidemias de malária, nosso interesse voltou-se para conhecer as espécies de anofelinos vetoras. Nos anos de 2002 a 2004 foram realizadas coletas periódicas de mosquitos adultos utilizando-se o método de captura manual com atrativo humano no peridomicílio. Foram realizadas seis coletas bimensais com duração de 6 horas com o registro de apenas duas espécies em atividade atacando o homem, Anopheles (Nyssorhynchus) aquasalis e Anopheles (Anopheles) intermedius. Verificou-se que as condições climáticas, o comportamento dos residentes e a falta de recursos para o efetivo lcontrole dos vetores da doença, favorecem a persistência de malária na Ilha de Cotijuba.

Bromeliad-associated mosquitoes from Atlantic forest in Santa Catarina Island, southern Brazil (Diptera, Culicidae), with new records for the State of Santa Catarina

Bromeliad-associated mosquitoes (Diptera: Culicidae) in Atlantic Forest in Florianópolis, Santa Catarina, southern Brazil, were studied, examining plants of Vriesea philippocoburgi Wawra and Aechmea lindenii (E. Morren) Baker var. lindenii at secondary Atlantic rain forest, and A. lindenii and Vriesea friburgensis Mez var. paludosa (L. B. Smith) at "restinga" per month, during 12 months. No immature forms of mosquitoes were collected from A. lindenii in the secondary forest. Collections obtained 368 immature mosquitoes, none of them from A. lindenii from rain forest. Culex (Microculex) spp. constituted 79.8% of the total, Wyeomyia (Phoniomyia) spp. 17.93%, and Anopheles (Kerteszia) cruzii (Dyar & Knab, 1908) only 1.36%. The study shows the great predominance of species of medical importance not yet proved, and the small number of immature stages of anopheline mosquitoes. The rainfall, but not the mean temperatures, significantly influenced the quantity of mosquitoes from V. philippocoburgi. Significant differences between the quantities of immature forms of all the bromeliad species were found, and the shape of the plants could be important to the abundance of mosquitoes. All six species of Cx. (Microculex) found are recorded for the first time in the State of Santa Catarina, and all six species of Wyeomyia (Phoniomyia) are recorded for the first time in bromeliads in this state.

Sobre o preparo dos parasitas da malária em distensões espessas, especialmente em amostras supersecas

I) the A. presents a method developed for the preparation of thick blood films, specially old desiccated smears. The observations are based on the experience of more than 53000 blood samples collected in the laboratory of the “Serviço de Malaria do Nordeste” as well as in the research department of the “Serviço de Malaria da Baixada Fluminenese”. II) As in introductory matter, he emphasizes the value of the obstacles presented by overdrying of the thick blood films occurring systematically in great malaria control organizations in which the laboratory receives materials from more or less remote localities, particularly in the Brazilian northeast, in regions invaded by Anopheles gambiae. III) An analysis of the causes of failure of the methods of Chorine and Knowles recorded in the literature for such purposes is given, as well as its adaptability for the simultaneous preparation of large numbers of samples. IV) The method is based the protective action of a previous fixation by a dilute solution of formalin, which, without preventing further dehemoglobinization, prevents morphological alterations in the parasites by the action of Knowles solution which is retained in this metod without modification. V) For washing out the acids of the dehemoglobinizating solution as well as for diluting the Giemsa stain, the A. proposes a very simple technique, extremely convenient for such purpose, which consists in adding acetic acid to the distilled water in the proportion of 1 drop for each 10cc of water, and then increasing the hydrogeni-on concentration to pH 7.2 with a 2% sol. of sodium carbonate. As indicator a 0.02% solution purple-bromcresol prepared in accordante to Medalia, is used. In this reaction there is the formation of the acetic acid ↔ sodium acetate, buffer system very suitable for giving a convenient pH and for preventing the precipitation of the dye, which can be used for two or three batches of 700 or 800 slides each, without changing the staining solution. VI) – The method can be summarized as follow: For a small number of samples, Coplin’s or any other staining jar can be used. Large number of slides must be placed in groups of 10 or 15 units each, the slides being separated by a piece of cardboard, according to Barber & Komp. A) Fix in dilute formalin (2%), during 5 minutes. b) Without washing, put in Knowles solution (see the formula in the text), no more than 20 minutes. c)Two successive washings in distilled water, buffered as explained above (which can be used several times). d) Dry and stain with Giemsa solution, prepared by using 1 drop of the stain for each c. c. of buffered distilled water. Time: 1 hour. E) Was in distilled water and dry.

Uma estação biológica para o estudo dos mosquitos e dos outros animaes silvestres relacionados com a febre amarela

The outbreak of the jungle or forest yellow fever, through the adapta¬tion, quite recently of the yellow fever virus o the forest mosquitoes, brou¬ght the necessity of ecological researches on hese mosquitoes, as well as on the wild animals they bite, some of them being susceptible to the desease. This has been done by the special yellow fever Service of the State of Sao Paulo, in a special Biological Station in Perús, São Paulo, which has been built in the midst of the jungle. This station was made with plain materials, and covered with straw, but was confortable enough for the technical work, i nthe early months of 1938. During the months in which the investigations were being carried on, the following interesting results were obtained: 1. As we have already pointed out in other places, the forest mosquitoes biting us during daytime, are always new born insects, having not yet sucked blood, as it is the general rule with all mosquitoes, and therefore also, with the anopheles and stegomyia, and this explains why nobody gets malaria or yellow fever, transmitted by anofeles or by aedes aegypti during the day. We think therefore, the jungle yellow fever, got during daytime is not due to the infected jungle or forest mosquito biting, but to infection through the human skin coming into close contact with tre virus, which the forest mosquitoes lay with their dejections, on the leaves of the trees where they remain sitting du¬ring the day. 2. As it is the rule with anopheles, stegomyia and other mosquitoes, the insects once having sucked blood, take nocturnal habits and, therefore, bite us, only during the night, so it happens with the forest mosquito, and insects with developped eggs and blood in stomach have been caught within the sta¬tion house, during the night. During the day, these mosquitoes do not bite, but remain quite still on the leaves of the trees, in the damp parts of the woods. 3. Jungle or forest mosquitoes can easely bite wild animals, some with more avidity then ethers, as it has bee npointed out to the opossum (didei-phis) and other animals. They also bite birds having very thin skin and only exceptionally, cold bloods animals. 5. Is has hot been possible to ascertain how forest mosquitoes are able to live, from onde season to another, through winter, when temperature drops near and even below zero. They have not been found in holes of the terrain, of trees and of animals, as it is the rule in cold countries. During winter, in the forest, it is possible to find larvs in the holes of bambus and trees full of water. As wild animals do not harbour the yellow fever virus for a long time in their body, it is diffcult to explain how the desease lasts from one season to another. Many ecological features on the mosquito, remains yet to be explained and therefore it in necessary to go on with the investigations, in bio¬logical stations, such as that one built up in Perús, São Paulo.

Verificação, em condiçoes naturais, da infecção de mais três hematófagos (Anophelineos, Flebótomos e Simulídeos) em leprosos

The A. went last August to the State of Minas Gerais to continue his studies on transmission of leprosy by insects. He selected ten lepers (all L3 cases) for his experiments. It happened in the middle of August, a few day after freezing temperature. Practically there were no day mosquitoes, even near a river where in March there were very many. Bringing the patients to a wood, near the Peixe River (Fish River), at the dawn they were attacked by very many Anopheles, some flebotomus, a few Simulium and very rare Culex scapularis. All these insects became infected, in different degrees, by biting such patients. CONCLUSIONS. 1. Two species of Anopheles (A. albitarsis and A. tarsimaculatus) became strongly infected by Hansen bacilli. 2. By dissection done by Dr. Oliveira Castro were found lepra bacilli in various points of the proboscis of two Flebotomus (F. intermedius) and in their stomachs. 3. By smearing were found lepra bacilli in two specimens of Simulium sp. (probably pertinax). 4. It was confirmed also the verification done last March, at the same Leper Colony, that Phthirius pubis can be also a carrier of lepra bacillus. 5. There was confirmed also natural infection of nymphs of Amblyomma cajennense in lepers. Dr. Oliveira Castro is dissecting the Anopheles to locate the bacilli in their organisms and he started, with the cooperation of the Director of Colonia Santa Fé, Dr. José Mariano, attenpts to re-infect a group of negative-nerve cases of leprosy with infected mosquitoes.

Os anofelinos do sub-gênero kerteszia em relação à distribuição das bromeliáceas em comunidades florestais do município de Brusque, Estado de Santa Catarina

The present work is part of the studies realized under the authority of the National Service of Malaria (Brazil), with the collaboration of scientists of the Oswaldo Cruz Institute, in some forests of the southern part of Brazil.This is the first of a series and its subject is the development of the Anopheles mosquitoes of the kerteszia in water collected in Bromeliaceae leaves. The ecology of Bromeliaceae was studied in a previous work. The botanical material was classified by specialists from several botanical institutions from Europe and the United States of America. The most important ecological relations of the “bromeliad-kerteszia” problem were presented through four indices: 1st Positivity index – Relative frequency of bromeliad with watery forms in the bromeliad examined. 2nd Larval index – Mean number of watery forms in the positive bromeliad. 3rd Ovoposition index – Product of the Positivy index by the Larval index. 4th MK index – Product of the Ovoposition index by the total number of bromeliad, positive or not, in a unity of area (1.000 m²). The capture of flying forms in relation to the relative humidity was also studied. From the several forests of the Brusque region we have selected one community of each type, which were the most representative forests in Southern Brazil. Conclusions on the “bromeliad-kerteszia” problem – From a general point of view only a few factors are really important and these are listed below: 1°) The volum of water on the bromeliad. 2°) The level where the bromeliad is fixed. 3°) The number of bromeliad in unity of area. The distribution of microclimas in the forest through the considered levels has a direct influence on the species of subgenus Kerteszia (qualitative influence) and an indirect influence through the ecological distribution of the more frequent bromeliad with best qualities as biotope for the watery forms (qualitative influence). The MK index is roughly proportional to the square of half the total number of Bromeliaceae in a certain type of forest. Then the MK index would be a certain function of the ecological type of the forest and of the total number of bromeliad in a unity of area. MK approximately α x (x/10)² . x = n° of bromeliad in a unity of área (1.000 m²); α = qualitative factor. It would be interesting to see if this proportion is maintained when we have examined a greater number of forests of different types.