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Advances in diagnostic techniques coupled with ongoing environmental changes have resulted in intensified surveillance and monitoring of arbovirus circulation in the Amazon. This increased effort has resulted in increased detection of insect-specific viruses among hematophagous arthropods collected in the field. This study aimed to document the first isolation of Agua Salud alphavirus in mosquitoes collected within the Brazilian Amazon. Arthropods belonging to the family Culicidae were collected within a forest fragment located in the Environmental Protection Area of the metropolitan region of Belem. Subsequently, these specimens were meticulously identified to the species level. Afterward, the collected batches were macerated, and the resulting supernatant was then inoculated into C6/36 and Vero cell cultures to facilitate viral isolation. The presence of arboviruses within the inoculated cell cultures was determined through indirect immunofluorescence analysis. Furthermore, positive supernatant samples underwent nucleotide sequencing to precisely identify the viral strains present. Notably, a batch containing Culex (Melanoconion) mosquitoes was identified to be positive for the genus Alphavirus via indirect immunofluorescence. This study is the first report on insect-specific alphavirus isolation in Brazil and the first-ever description of Agua Salud alphavirus isolation within Amazon Forest remnants.

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The genus Orthopodomyia Theobald, 1904 (Diptera: Culicidae) comprises 36 wild mosquito species, with distribution largely restricted to tropical and temperate areas, most of which are not recognized as vectors of epidemiological importance due to the lack of information related to their bionomy and involvement in the cycle transmission of infectious agents. Furthermore, their evolutionary relationships are not completely understood, reflecting the scarcity of genetic information about the genus. Therefore, in this study, we report the first complete description of the mitochondrial genome of a Neotropical species representing the genus, Orthopodomyia fascipes Coquillet, 1906, collected in the Brazilian Amazon region. Using High Throughput Sequencing, we obtained a mitochondrial sequence of 15,598 bp, with an average coverage of 418.5×, comprising 37 functional subunits and a final portion rich in A + T, corresponding to the control region. The phylogenetic analysis, using Maximum Likelihood and Bayesian Inference based on the 13 protein-coding genes, corroborated the monophyly of Culicidae and its two subfamilies, supporting the proximity between the tribes Orthopodomyiini and Mansoniini, partially disagreeing with previous studies based on the use of molecular and morphological markers. The information generated in this study contributes to a better understanding of the taxonomy and evolutionary history of the genus and other groups of Culicidae.

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The genus Limatus (Diptera: Culicidae) are wild mosquitoes belonging to the Sabethini tribe that occurs in tropical countries and is related to transmission cycles of Orthobunyavirus (Bunyaviridae), particularly in the Amazon region. Given the unavailability of information related to evolutionary biology and molecular taxonomy aspects of this genus, we report here the first complete sequencing of the mitochondrial genome of Limatus durhamii Theobald, 1901. The NextSeq 500 platform was used for sample sequencing, and the mitochondrial sequence obtained was 14,875 bp long, comprising 37 functional subunits (13 PCGs, 22 tRNA and 02 rRNA). The phylogeny reconstructed by maximum likelihood based on the concatenation of all 13 PCGs corroborated the known taxonomic classification based most on aspects of the external morphology and few molecular studies. The data and information produced here may be useful in the future development of taxonomic and evolutionary studies for the genus, as well as the Culicidae family itself.

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The rapid and disorderly urbanization in the Amazon has resulted in the insertion of forest fragments into cities, causing the circulation of arboviruses, which can involve hematophagous arthropods and free-ranging birds in the transmission cycles in urban environments. This study aimed to evaluate the circulation of arboviruses in free-ranging birds and hematophagous arthropods captured in an Environmental Protection Area in the Belem metropolitan area, Brazil. Birds were captured using mist nets, and hematophagous arthropods were collected using a human protected attraction technique and light traps. The birds' sera were subjected to a hemagglutination inhibition test to detect antibodies against 29 arbovirus antigens. Arthropod macerates were inoculated into C6/36 and VERO cell cultures to attempt viral isolation and were tested using indirect immunofluorescence, subsequent genetic sequencing and submitted for phylogenetic analysis. Four bird sera were positive for arbovirus, and one batch of Psorophora ferox was positive for Flavivirus on viral isolation and indirect immunofluorescence. In addition, the Ilheus virus was detected in the sequencing and phylogenetic analysis. The presence of antibodies in sera from free-ranging birds and the isolation of Ilheus virus in Psorophora ferox indicate the circulation of arboviruses in forest remnants in the urban center of Belem.

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The genus Aedes (Diptera: Culicidae) includes species of great epidemiological relevance, particularly involved in transmission cycles of leading arboviruses in the Brazilian Amazon region, such as the Zika virus (ZIKV), Dengue virus (DENV), Yellow fever virus (YFV), and Chikungunya virus (CHIKV). We report here the first putatively complete sequencing of the mitochondrial genomes of Brazilian populations of the species Aedes albopictus, Aedes scapularis and Aedes serratus. The sequences obtained showed an average length of 14,947 bp, comprising 37 functional subunits, typical in animal mitochondria (13 PCGs, 22 tRNA, and 2 rRNA). The phylogeny reconstructed by Maximum likelihood method, based on the concatenated sequences of all 13 PCGs produced at least two non-directly related groupings, composed of representatives of the subgenus Ochlerotatus and Stegomyia of the genus Aedes. The data and information produced here may be useful for future taxonomic and evolutionary studies of the genus Aedes, as well as the Culicidae family.

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The Culicidae family is distributed worldwide and comprises about 3587 species subdivided into the subfamilies Anophelinae and Culicinae. This is the first description of complete mitochondrial DNA sequences from Aedes fluviatilis, Aedeomyia squamipennis, Coquillettidia nigricans, Psorophora albipes, and Psorophora ferox. The mitogenomes showed an average length of 15,046 pb and 78.02% AT content, comprising 37 functional subunits (13 protein coding genes, 22 tRNAs, and two rRNAs). The most common start codons were ATT/ATG, and TAA was the stop codon for all PCGs. The tRNAs had the typical leaf clover structure, except tRNASer1. Phylogeny was inferred by analyzing the 13 PCGs concatenated nucleotide sequences of 48 mitogenomes. Maximum likelihood and Bayesian inference analysis placed Ps. albipes and Ps. ferox in the Janthinosoma group, like the accepted classification of Psorophora genus. Ae. fluviatilis was placed in the Aedini tribe, but was revealed to be more related to the Haemagogus genus, a result that may have been hampered by the poor sampling of Aedes sequences. Cq. nigricans clustered with Cq. chrysonotum, both related to Mansonia. Ae. squamipennis was placed as the most external lineage of the Culicinae subfamily. The yielded topology supports the concept of monophyly of all groups and ratifies the current taxonomic classification.

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Insects have evolved multiple mechanisms to adapt to variations in environmental temperatures, including postural control of solar input, variations in diurnal activity, external morphological structures and selecting/generating microhabitats. Foam produced by Mahanarva fimbriolata nymphs (also known as root spittlebugs) was found to aid in creating a constant thermal microhabitat despite environmental temperature fluctuations. The temperature within the foam was found to be similar to that of soil during the day and remained constant despite fluctuating external temperatures. In chemically analysing the composition of the foam, palmitic and stearic acids, carbohydrates and proteins were detected. These substances have previously been shown to act as a surfactant to stabilize and modulate foams. Since the immature ancestor of the spittlebug developed below ground, it is speculated that the foam may function as an 'extension' of the soil and, thus, may have enabled the spittlebug to emerge from the soil and adopt an epigean lifestyle.

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OBJETIVO: Avaliar a duração do efeito residual de piretróides sobre a mortalidade de anofelinos e verificar sua efetividade na borrifação intradomiciliar em regiões da Amazônia Brasileira. OBJETIVO: O estudo foi desenvolvido no conjunto habitacional, município de Belém, Pará, em 2003. Foram sorteadas 12 casas, três de cada uma das quatro áreas estabelecidas. Foram aplicados nas paredes internas das casas os inseticidas: piretróides cipermetrina pó molhável, deltametrina suspensão concentrada, lambdacialotrina pó molhável e etofemprox pó molhável. Seu efeito sobre a mortalidade de anofelinos foi avaliado durante os meses de julho a novembro. Utilizou-se a técnica de prova biológica de parede com a utilização de cones plásticos e mosquitos selvagens do município de Peixe Boi. RESULTADOS: A taxa de mortalidade variou de acordo com o tipo de parede e inseticida aplicado. Os aplicados em madeira e paredes de tijolo sem reboco foram mais estáveis e duradouros. O lambdacialotrina apresentou efeito mais curto que os demais inseticidas e o etofemprox apresentou efeito residual de quatro meses e foi mais efetivo em paredes de tijolo sem reboco. Não houve diferença estatística entre deltametrina e cipermetrina em todas as superfícies testadas, e a duração do efeito residual foi satisfatória até três meses após a borrifação. CONCLUSÕES: Os inseticidas deltametrina e etofemprox apresentaram melhor desempenho quando comparados aos demais. Para esses inseticidas e formulações, deve considerar-se seguro o intervalo de três meses entre aplicações sucessivas. Em comunidades com predomínio de casas de alvenaria rebocadas, deve ser considerada a menor efetividade das formulações, bem como a pertinência do emprego da borrifação residual como método para o controle vetorial na área.

OBJECTIVE: To evaluate the residual effect of pyrethroids on the mortality rates of Anopheles in order to check their efficacy in indoor residual spraying in the Amazon Region, Brazil. METHODS: The study was conducted in public housing unities in the city of Belem, Northern Brazil, in 2003. Twelve houses were randomly chosen, three in each of the four established areas. Pyrethroids cypermethrin wettable powder, deltamethrin suspension concentrate, lambda-cyhalothrin wettable powder, and etofenprox wettable powder, were sprayed on the indoor wall surface of local houses. Their effects on the mortality of Anopheles were assessed from July to November. Wall bioassay was performed using plastic cones attached to insecticide and wild mosquitoes from the town of Peixe Boi. RESULTS: Mortality rate varied according to the type of wall that received the insecticide. Those inseticides applied to wood and non-plastered brick surfaces were more stable and lasted longer. Lambda-cyhalothrin presented shorter effect than the other insecticides, and Etofenprox had residual effects up to four months and was more effective in non-plastered brick surfaces. There was no statistical difference between the effect of deltamethrin and cypermethrin in all surfaces tested, and the duration of the residual effect was satisfactory up to three months after spraying. CONCLUSIONS: Deltamethrin and Etofenprox presented grater performance when compared to the others. For these insecticides and formulations, a three- month interval between successive applications can be considered safe. In communities with predominance of houses with plastered brick surfaces, the smaller effectiveness of formulations should be considered, together with the importance of residual spraying as a vector control method in the area.

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OBJECTIVE: To evaluate the residual effect of pyrethroids on the mortality rates of Anopheles in order to check their efficacy in indoor residual spraying in the Amazon Region, Brazil. METHODS: The study was conducted in public housing units in the city of Belem, Northern Brazil, in 2003. Twelve houses were randomly chosen, three in each of the four established areas. Pyrethroids cypermethrin wettable powder, deltamethrin suspension concentrate, lambda-cyhalothrin wettable powder, and etofenprox wettable powder, were sprayed on the indoor wall surface of local houses. Their effects on the mortality of Anopheles were assessed from July to November. Wall bioassay was performed using plastic cones attached to insecticide and wild mosquitoes from the town of Peixe Boi. RESULTS: Mortality rate varied according to the type of wall that received the insecticide. Those insecticides applied to wood and non-plastered brick surfaces were more stable and lasted longer. Lambda-cyhalothrin presented shorter effect than the other insecticides, and etofenprox had residual effects up to four months and was more effective in non-plastered brick surfaces. There was no statistical difference between the effect of deltamethrin and cypermethrin in all surfaces tested, and the duration of the residual effect was satisfactory up to three months after spraying. CONCLUSIONS: Deltamethrin and etofenprox presented greater performance when compared to the others. For these insecticides and formulations, a three-month interval between successive applications can be considered safe. In communities with predominance of houses with plastered brick surfaces, the smaller effectiveness of formulations should be considered, together with the importance of residual spraying as a vector control method in the area.

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As siliconas polimerizadas por adiçäo, säo cada vez mais utilizadas para obtençäo de moldagens pelos Cirurgiöes-Dentistas, pois näo necessitam que o mesmo construa seu modelo de trabalho dentro da primeira hora, após a obtençäo do molde. Nesta pesquisa procuramos verificar a necessidade, ou näo, de realizar alívios no molde com silicona pesada e qual sua influência sobre a fidelidade de reproduçäo de um corpo de prova padräo

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O efeito da fluidez de uma soluçäo endurecedora na expansäo de presa do gesso pedra melhorado, foi estudado em 2 marcas comerciais usando-se espatulaçäo manual e mecânica e 4 diferentes líquidos de mistura: água de abastecimento, água mineral e duas soluçöes endurecedoras de fluidez diferentes. Foram usados 80 corpos de prova nos 4 grupos, formando 16 subgrupos. A expansäo média apresentou diferenças quanto ao tipo de espatulaçäo e o líquido usado, mas näo quanto à marca comercial. A expansäo média obtida com os diferentes líquidos apresentou a seguinte ordem soluçäo endurecedora fluída (0,1375), água de abastecimento (0,1078), água mineral (0,0999) e soluçäo endurecedora menos fluída (0,0782). É possível concluir que uma soluçäo endurecedora menos fluída diminui a expansäo de presa do gesso estudado

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