Introdução: Parques inseridos na malha urbana de grandes metrópoles possuem potencial para manter o ciclo biológico de diversas espécies vetoras de patógenos, como as espécies Culex quinquefasciatus e Culex nigripalpus. Consideradas antropofílicas, essas espécies têm importância epidemiológica e são abundantemente encontradas na cidade de São Paulo. Porém, pouco se sabe sobre as características genéticas dessas espécies em escala microgeográfica. Visando o melhor entendimento sobre a estrutura populacional dessas espécies, foi analisado os padrões da forma alar e a caracterização genética por marcadores de microssatélites, afim de se obter informações que contribuam para o entendimento da situação populacional desses vetores dentro do município. Objetivos: (1) Analisar a variabilidade da forma alar nas populações de Cx. quinquefasciatus e Cx. nigripalpus; (2) Analisar a variabilidade genética e o fluxo gênico nas mesmas populações; (3) Testar a funcionabilidade de primers desenvolvidos para regiões de microssatélites nas populações de Cx. nigripalpus. Material e Métodos: No total, foram estudadas cinco populações de Cx. quinquefasciatus e sete populações de Cx. nigripalpus, coletados em parques urbanos da cidade de São Paulo. Análises discriminantes, como variável canônica, teste de reclassificação cruzada e dendrograma de Neighbor-joining, utilizando os software Morpho J e Past, foram realizadas para a compreensão do formato e tamanho da asa direita nas populações. Em relação ao estudo da estruturação genética, foram testados 12 pares de primers de microssatélites em mosquitos Cx. quinquefasciatus e 33 pares de primers em mosquitos Cx. nigripalpus. Resultados: Análise da morfometria geométrica alar nas populações de Cx. quinquefasciatus demonstrou homogeneidade nos formatos alares, sendo um caracter preservado nessa espécie pela cidade, contudo, há tênues diferenças na população coletada em ambiente mais silvestre. O mesmo foi observado para as populações de Cx. nigripalpus, onde foi possível visualizar uma subestruturação na forma alar dentro da população Shangrilá. Dos primers testados, 12 amplificaram de forma consistente em todas as populações de Cx. quinquefasciatus e seis primers nas populações de Cx. nigripalpus. Os resultados encontrados sugerem que ambas as espécies possuem baixa estruturação genética, com fluxo gênico moderado entre as populações de Cx. quinquefasciatus e baixo entre as de Cx. nigripalpus, apresentando alto índice de heterozigosidade, onde as únicas populações que estão em expansão são as que foram coletadas em ambientes onde a urbanização está avançando. Discussão: Processos de urbanização, somados às mudanças causadas no ambiente, beneficiam e tendem a elevar a abundância dessas espécies em ambientes antropizados. A baixa estruturação genética e morfométrica das asas dessas espécies indicam a adaptação delas na cidade, havendo segregação devido à heterogeneidade do ambiente em que as populações se encontram. Conclusão: Evidências de baixa estruturação entre as populações e indícios de expansão em populações de ambientes mais silvestres indicam que essas espécies estão atreladas ao processo de urbanização da cidade de São Paulo / Introduction: Urban parks have the potential to harbor and maintain the life cycle of several mosquitoes such as Culex quinquefasciatus and Culex nigripalpus, both are anthropophilic species with epidemiological importance and very abundant in São Paulo city. However, their genetics characteristics are poorly know. Aiming the better understanding of the population structure of these species in microregion, was evaluated the wing shape variation and selected microsatellite loci. In this way, the information obtained can contribute to the understanding of the population situation of these vectors in São Paulo city. Objectives: (1) To evaluate the wing shape variability in populations of Cx. quinquefasciatus and Cx.nigripalpus; (2) To evaluate the genetic variability and gene flow in the Cx. quinquefasciatus and Cx.nigripalpus populations (3) Test microsatellite markers functionality parameters in Cx. nigripalpus, previously used successfully in other Culex species. Material and Methods: Were studied, five populations of Cx. quinquefasciatus and seven population of Cx. nigripalpus collected in urban parks in São Paulo city. Discriminant analysis was made to evaluate the wing shape patterns, such as Canonical variate analysis, cross validated test and Neghbor-joninin dendrogram using Morpho J and Past softwares, were perfomed to understand the size and shape of the right wing in these populations. For the study of genetic structuring, there were tested 12 pairs of microsatellite loci in Cx. quinquefasciatus samples and 33 pairs of microsatellite loci in Cx. nigripalpus samples. Results: The wing shape patterns in Cx. quinquefasciatus population were homogeneous, showing a preserved character in this population, however, has been tenuous differences in the more sylvatic population. The same pattern was observed in Cx. nigripalpus populations and was observed substructuring in the Shangrilá population. From the tested primers, 12 were functional and amplified consistently in the all five Cx. quinquefasciatus population and for Cx. nigripalpus, six primers were amplified. The results suggest both species having low genetic structure, moderate gene flow and the only populations which are expading were collected in areas that the urbanization is increasing. Discussion: Urbanization processes added to the environmental changes benefit and tend to raise the abundance of these species in anthropized locals. The low genetic structure and alar morphometry indicates the adaptation of these species in São Paulo city, there being segregated due to the environment heterogeneity which the population inhabit. Conclusion: Evidence of low structure between populations studied and signs of expansion in populations of more sylvatic environments indicate that these species are linked to urbanization process

O diptero Culex quinquefasciatus, devido ao seu interesse médico, tem sido alvo de diversas tentativas de controle populacional que acabam enfrentando como fator limitante a microevolução. Para verificar a presença de variação populacional indicativa de microevolução, foram coletadas e comparadas amostras de dois locais dentro do Estado de São Paulo: O Parque Ecológico do Tietê, no município de São Paulo e em Pariquera-Açú, no Vale do Ribeira. A análise morfométrica das asas revelou que há diferença de forma e tamanho entre as populações e que o dimorfismo sexual é evidente e a assimetria bilateral alar é pouco pronunciada nas duas populações. A micrografia de ovos mostrou diferenças interpopulacionais quanto à altura dos tubérculos do exocórion. O padrão de bandas observado na análise do DNA ribossômico foi homogêneo. O fluxo gênico entre essas populações parece reduzido, fato que reflete diretamente a dinâmica dispersional desses mosquitos, fenômeno que pode ter implicações diretas na transmissão de eventuais doenças veiculadas por esses insetos. / Culex quinquefasciatus is a pantropical synanthropic species of great medical interest. Several attempts to control this species have fail due to its microvelution of resistance to insecticides. In order to detect populational variation indicative of microevolution, two populational samples from State of São Paulo were compared: São Paulo municipality (Park Ecológico do Tietê) and Pariquera-Açú municipality. Biological parameters were wing morphometrics, exochorion micrography and ribosomal DNA. Wings characters revealed shape and size divergencies between populations. Exochorion were also interpopulationally different. Polymorphisms observed may be a result of genetic differentiation. rDNA was homogeneous intra and interpopulationally. Gene flow between populations appears to be reduced, which may be closely related to the dispersional dynamics of these mosquitoes. Such interpretation is relevant to a better understanding of transmission of diseases by these insects.

Wolbachia é uma bactéria endossimbionte que interfere na reprodução de seus hospedeiros. Dentre os efeitos estão: partenogênese, morte dos machos, feminização, alterações na aptidão reprodutiva e incompatibilidade citoplasmática. Este trabalho avalia e compara as diferenças fisiológicas e reprodutivas entre Culex quinquefasciatus infectados e não-infectados por Wolbachia. As larvas de mosquitos não-infectadas atingem o estágio adulto anteriormente. As fêmeas adultas não- infectadas têm maior capacidade de depositar ovos, depositam uma maior quantidade de ovos e estes são também mais viáveis. Em contrapartida as fêmeas infectadas vivem mais tempo quando alimentadas com sangue, e necessitam de menos tempo, após a alimentação sanguínea, para depositar ovos. O fato de os mosquitos não-infectados terem uma melhor aptidão reprodutiva pode estar relacionado a diferenças na quantidade de vitelogenina. Constatamos que o tamanho alar não é significativamente alterado com a desinfecção, porém a assimetria bilateral alar dos mosquitos infectados é mais acentuada. / Wolbachia is an endosymbiont bacterium that interferes on reproduction of their hosts. It can cause: parthenogenesis, male-killing, feminilization, alterations in reproductive fitness and cytoplasmic incompatibility. This study evaluated and compared physiological and reproductive differences between Culex quinquefasciatus infected and non-infected with Wolbachia. We noted that the mosquito larvae of non-infected mosquitoes reach the adult stage earlier. Uninfected adult females have higher ability to lay eggs, lay more eggs and those eggs have higher viability. In contrast, infected females live longer when fed with blood, and require less time after blood feeding to lay eggs. The fact that non-infected mosquitoes have better reproductive fitness may be related to differences in the amount of vitellogenin. We noted that wing size is not significantly altered by the infection, and that the infected mosquitoes showed higher bilateral wing asymmetry.

<p>Meteorological&nbsp; conditions&nbsp; have&nbsp; a&nbsp; significant influence on the time of occurrence, abundance and activity of the mosquito vector. In the current context of climate change, it is of great importance to assess the&nbsp; impact&nbsp; of&nbsp; shifts&nbsp; in&nbsp; climatic&nbsp; conditions&nbsp; on&nbsp; the suitability for the establishment and annual activity of&nbsp; the&nbsp; vector&nbsp; species.&nbsp; Moreover,&nbsp; changes&nbsp; in&nbsp; the variability&nbsp; of&nbsp; meteorological&nbsp; elements&nbsp; and&nbsp; their extremes&nbsp; can&nbsp; generate&nbsp; unexpected&nbsp; changes&nbsp; in&nbsp; the mosquito&nbsp; vector&nbsp; population&nbsp; which&nbsp; in&nbsp; turn&nbsp; have&nbsp; an&nbsp; important effect on human health. One of the ways to put&nbsp; these&nbsp; causes&nbsp; and&nbsp; effects&nbsp; into&nbsp; perspective&nbsp; is&nbsp; to simulate the activity of the vector within a processbased framework which allows for the analysis of the contribution of individual factors on the different life stages of the vector. Such analysis is presented by use of&nbsp; sophisticated&nbsp; dynamical&nbsp; models&nbsp; simulating&nbsp; the characteristics of the biological population, forced by observed&nbsp; meteorological&nbsp; data,&nbsp; capturing&nbsp; the&nbsp; localmicro-environment&nbsp; of&nbsp; the&nbsp; vector&nbsp; habitat,&nbsp; and validated by the observed entomology.Numerical&nbsp; models&nbsp; are&nbsp; being&nbsp; developed&nbsp; to&nbsp; model vector&nbsp; population&nbsp; dynamics&nbsp; and&nbsp; the&nbsp; expected circulation of the virus within a closed system. Two modelling&nbsp; approaches&nbsp; are&nbsp; standardly&nbsp; applied&nbsp; to modelling vector population dynamics: Mechanistic and&nbsp; Stochastic.&nbsp; The&nbsp; advantage&nbsp; of&nbsp; mechanistic&nbsp; over<br />statistical&nbsp; models&nbsp; is&nbsp; that&nbsp; they&nbsp; can&nbsp; provide&nbsp; a deterministic&nbsp; framework&nbsp; allowing&nbsp; for&nbsp; the&nbsp; isolated evaluation of each input parameter and their effect on the modelled system. Mechanistic dynamical models are used to describe the biophysical processes or part<br />of&nbsp; the&nbsp; process&nbsp; as&nbsp; a&nbsp; response&nbsp; to&nbsp; changes&nbsp; in&nbsp; the meteorological conditions.<br />The&nbsp; work&nbsp; carried&nbsp; out&nbsp; in&nbsp; this&nbsp; thesis&nbsp; can&nbsp; be summarized as follows: (i) Analysis of the association between&nbsp; the&nbsp; most&nbsp; important&nbsp; abiotic&nbsp; drivers influencing the population dynamics, annual activity and&nbsp; time&nbsp; of&nbsp; occurrence&nbsp; of Culex&nbsp; pipiens and Aedes aegypti;&nbsp; (ii)&nbsp; Identifying&nbsp; the&nbsp; most&nbsp; important&nbsp; climatic factors and model settings as a function of climatic characteristics of the study region; (iii) Modelling the vector population dynamics and stability analysis of the&nbsp; dynamical&nbsp; system&nbsp; (iv)&nbsp; Analysis&nbsp; of&nbsp; different verification techniques and implications in terms of model&nbsp; application;&nbsp; (v)&nbsp; Feasibility&nbsp; analysis&nbsp; of<br />improving&nbsp; the&nbsp; model&nbsp; with&nbsp; a&nbsp; Land-Surface Parametrization scheme and short-range forecasting of pest population dynamics.</p> / <p>Meteorolo&scaron;ki&nbsp; uslovi&nbsp; bitno&nbsp; utiču&nbsp; na&nbsp; vreme&nbsp; pojave, brojnost&nbsp; vektora&nbsp; i&nbsp; njihovu&nbsp; aktivnost.&nbsp; U&nbsp; uslovima evidentnih promene klime, od ogromne je važnosti sagledati&nbsp; uticaj&nbsp; očekivanih&nbsp; promena&nbsp; klime&nbsp; na pogodnost&nbsp; uslova&nbsp; na&nbsp; pojavu&nbsp; izabranih&nbsp; vektora.<br />Takodje, značajne promene kolebanja meteorolo&scaron;kih elemenata&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; vi&scaron;egodi&scaron;nji&nbsp; prosek&nbsp; i&nbsp; sve če&scaron;će pojave nepovoljnih vremenskih prilika dovode do neočekivanog pona&scaron;anja populacije komarca &scaron;to značajno&nbsp; utiče&nbsp; na&nbsp; kvalitet&nbsp; života&nbsp; i&nbsp; zdravlje&nbsp; ljudi. Jedini&nbsp; način&nbsp; da&nbsp; se&nbsp; sagledaju&nbsp; uzroci&nbsp; i&nbsp; posledice navedenih pojava zasniva se na simulaciji aktivnosti i&nbsp; brojnosti&nbsp; vektora&nbsp; uz&nbsp; mogućnost&nbsp; testiranja&nbsp; uticaja svakog&nbsp; pojedinačnog&nbsp; faktora.&nbsp; Ovu&nbsp; mogućnost pružaju samo visoko sofistikovani dinamički modeli koju su pro&scaron;li proces kalibracije i validacije zasnovan<br />na izmerenim vrednostima meteorolo&scaron;kih elemenata i karakteristika biolo&scaron;ke populacije.<br />Sofistikovani&nbsp; modeli&nbsp; za&nbsp; simulaciju&nbsp; dinamike populacije vektora i očekivane cirkulacije vektorskih transmisivnih bolesti se koriste sa ciljem modeliranja potencijalnog rizika od zaraze i epidemije. Modeli zasimulaciju dinamike vektora mogu da se podele na dve&nbsp; glavne&nbsp; grupe:&nbsp; Mehanističke&nbsp; i&nbsp; Statističke. Prednost&nbsp; mehanističkih&nbsp; modela&nbsp; nad&nbsp; statističkim&nbsp; je &scaron;to&nbsp; mogu&nbsp; da&nbsp; se&nbsp; koriste&nbsp; za&nbsp; evaluaciju&nbsp; uticaja izolovanog&nbsp; faktora&nbsp; na&nbsp; dinamički&nbsp; sistem&nbsp; i odgovarajuće promene brojnosti unutar svake faze u razvoju&nbsp; vektora.&nbsp; Mehanistički&nbsp; dinamički&nbsp; sistemi&nbsp; se koriste&nbsp; kako&nbsp; bi&nbsp; se&nbsp; opisao&nbsp; mehanizam&nbsp; biofizičkog procesa&nbsp; ili&nbsp; dela&nbsp; procesa&nbsp; u&nbsp; zavisnosti&nbsp; od&nbsp; forsirajuće veličine.<br />Predmet&nbsp; istraživanja&nbsp; u&nbsp; ovom&nbsp; radu&nbsp; jeste identifikovanje&nbsp; najznačajnijih&nbsp; biolo&scaron;kih&nbsp; i&nbsp; fizičkih procesa&nbsp; kao&nbsp; i&nbsp; odgovarajućih&nbsp; faktora&nbsp; koji&nbsp; utiču&nbsp; na brojnost i aktivnost vektora roda Aedes i Culex. Ciljevi istraživanja mogu da se sumiraju na sledeći način: (i)<br />analiza najznačajnijih meteorolo&scaron;kih parametara koji utiču na vreme pojave, brojnost i aktivnost vektora Aedes&nbsp; i&nbsp; Culex&nbsp; roda;&nbsp; (ii)&nbsp; definisanje&nbsp; najznačajnijih klimatskih&nbsp; faktora&nbsp; i&nbsp; stepena&nbsp; osetljivosti&nbsp; procesa&nbsp; na njih; (iii) modeliranje dinamike populacije vektora i analiza&nbsp; stabilnosti&nbsp; dinamičkog&nbsp; sistema;&nbsp;&nbsp; (iv) verifikacija&nbsp; i&nbsp; analiza&nbsp; metoda&nbsp; verifikacije&nbsp; i&nbsp; validacije dinamičkog&nbsp; modela;&nbsp; (v)&nbsp; kratkoročna&nbsp; prognoza dinamike&nbsp; populacije&nbsp; komarca&nbsp; i&nbsp; formulacija hidrolo&scaron;kog modula upotrebom SURFEX povr&scaron;inske<br />&scaron;eme sa ECOCLIMAP fiziogeografskim podacima.</p>

Field studies were conducted in southwestern Virginia to determine the bionomics and ovipositional preferences of Culex restuans Theobald and Culex pipiens Linnaeus using ovitraps and gravid traps. Both species have been implicated as enzootic and epizootic vectors of West Nile virus (WNV) and these studies provide information on the relative abundance of gravid mosquitoes. Ovitraps were used in the summers of 2002 and 2003 to measure the oviposition activity of Culex mosquitoes, mainly Cx. restuans and Cx. pipiens. In 2002, 1,345 egg rafts were collected from 5 traps set at different locations in the New River Valley (NRV). Cx. restuans constituted 93.2% of the catch; the remainder was Cx. pipiens (6.7%) and Cx. salinarius (<1%). In 2003, 4 ovitraps were placed at each of 6 locations in the NRV. Of 9,794 egg rafts collected, Cx. restuans comprised 92.8%, Cx. pipiens 6.5%, and Cx. salinarius <1%. Oviposition patterns were similar in both years. Cx. restuans oviposition was detected about mid-May, and raft numbers were highest in late June and the middle of July and then showed a steady decline throughout the remainder of each season. Cx. pipiens oviposition activity began later in the season and gradually increased, reaching its peak in August. Although the number of egg rafts of Cx. restuans decreased in August and September while the number of Cx. pipiens egg rafts increased, a crossover in the relative abundance of the two species never occurred. In 2003, the attractiveness of four infusions (cow manure, straw, grass, and rabbit chow) were compared in oviposition traps. For Cx. restuans, the manure infusions collected more egg rafts than the other three infusions for the first four weeks, with two of the weeks showing significance. During week 1, the manure infusions collected significantly more egg rafts than straw (P<0.01), grass (P<0.01), and rabbit (P<0.001). During week 2, manure collected more than grass (P<0.05) and rabbit (P<0.01). The straw and grass infusions yielded the most egg rafts after week 2, and only three weeks showed any significance. When traps began to collect Cx. pipiens, the majority were collected in the straw and grass infusions. During week 6, the hay infusions had significantly more egg rafts when compared to manure (P<0.001) and rabbit infusions (P<0.001) and the grass infusions had significantly more when compared to manure (P<0.05) and rabbit (P<0.01). Week 9 also showed significance when the hay infusions collected significantly more egg rafts than manure and rabbit (P<0.01 and P<0.01, respectively). The attractiveness of the cow manure and straw infusions were also compared in gravid traps. Because it is difficult to accurately discriminate between Cx. pipiens and Cx. restuans that have been collected as adults in gravid traps, these collections were combined into Culex. More Culex mosquitoes were collected in the manure infusions for the first two weeks (P<0.05). No significant differences were found between the numbers of mosquitoes captured in the traps baited with the different infusions after the second week. The shift observed in oviposition preference for both types of traps may have been due to cooler temperatures in the early part of the season. The straw infusions were aged outdoors for 3 days prior to use, and a sufficient incubation temperature to generate the bacteria producing the attractant chemicals may not have been attained. In addition, the manure lagoon had been drawn down and the consistency of the remaining manure became much drier by this time. No chemicals were ever added to the lagoon, but the draw down may have affected the attractiveness of the manure. / Master of Science

Introduction: Vector-borne infectious diseases represent a major public health problem in both developing and developed nations. In particular, West Nile Virus (WNV), a mosquito-borne disease that can lead to severe disease and death in humans, caused over 2,100 reported cases in the United States last year (CDC, 2016). In Maricopa County, Arizona WNV has caused 474 reported cases during the last five years, with a case-fatality rate at 7.8%. Aim: To examine the association between weather patterns and incidence of WNV in Maricopa County, AZ from 2007 to 2013. Methods: We analyzed weekly data on climatological variables and WNV incidence from Maricopa County, AZ. The specific independent variables of interest were precipitation, minimum temperatures, mean temperatures, and maximum temperatures. A full model was generated using multiple linear regression, and a stepwise selection procedure yielded a minimal model. Results: The full multiple linear regression model explains 45.30% of the observed variance in WNV incidence. The variable showing a significant impact on WNV incidence in this model was rainfall (p <0.0001). Stepwise selection results explained 45.16% of the variance observed in the data. This model included two significant predictors: precipitation and maximum temperature. Conclusion: Climatic variables, particularly the amount of rainfall and maximum temperatures, significantly influence WNV dynamics in Maricopa County, Arizona. These findings are in line with prior studies and could be useful to guide mosquito control programs in the state of Arizona.

Apresenta-se estudo da secção Spissipes de Culex (Melanoconion), baseado em caracteres morfológicos do cibário feminino. Após tecer considerações, incluindo o histórico, sobre os estudos taxonômicos do subgênero, considera-se a oportunidade do presente estudo, visando o encontro de novos elementos à taxonomia do grupo. De início procede-se à descrição morfológica geral do cibário, assinalando as diversas estruturas passíveis de serem utilizadas na caracterização taxonômica. Segue-se a descrição concernente a 14 (quatorze) espécies das 21 (vinte e uma) atualmente incluídas na secção Spissipes. O trabalho termina com discussão sobre os resultados obtidos. Estes vieram revelar a utilidade, a nivel específico, dos caracteres estudados. Boa parte deles, revelou-se passível de emprego a nivel de grupo. Nesse sentido, apresentaram aspectos característicos as seguintes espécies: Culex faurani Duret, Cx.lopesi Sirivanakarn e Jakob, Cx.nicaroensis Duret, Cx., ocossa Dyar e Knab, Cx. Spissipes Theobald e Cx.taeniopus Dyar e Knab. O trabalho conclui apresentando chave tentativa para identificação mediante o emprego desses caracteres. / The present paper describes some characters of the female cibarium, specially the cibarial armature of certain mosquitoes species commonly placed in the Spissipes section of the Culex (Melanoconion). After giving an account of the subgenus taxonomic history, the opportunity to find new subgeneric characters for taxonomic studies, is taken into consideration. Firstly is given a detailed description of the cibarium anatomy. Then are pointed out those structures of the bucal cavity, which may be useful to support the subgeneric classification. After this, descriptions of the adults female cibaria of 14 species, included in the Spissipes section, are given. Taxonomic implications of the cibarial characters are discussed. Our studies have shown that they may be useful in the subgeneric classification at specific level, as well as at group level. Particularly, characteristics features have been shown by some species as: Culex faurani Duret, Cx.lopesi Sirivanakarn and Jakob, Cx.nicaroensis Duret, Cx.ocossa Dyar and Knab, Cx. Spissipes Theobald and Cx.taeniopus Dyar e Knab. Finally, a tentative identification key is presented.

Submitted by Dominick Jesus (dominickdejesus@hotmail.com) on 2015-11-06T19:31:35Z No. of bitstreams: 2 Dissertação_Rafaela Augusta Mouzinho Bordalo.pdf: 3519525 bytes, checksum: c2c6204c8420d2aff0e7e7a06f977edb (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-06T19:31:35Z (GMT). No. of bitstreams: 2 Dissertação_Rafaela Augusta Mouzinho Bordalo.pdf: 3519525 bytes, checksum: c2c6204c8420d2aff0e7e7a06f977edb (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2011-03-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / It conducted a taxonomic study for the Culex species nigripalpus based on analyzes imorfológicas and molecular analysis with the "barcode" region of the COI gene. The analysis indicated that individuals in the US and Brazil do not differ as to infer that make up a species complex. In this case, the wide geographic distance did not represent a high genetic and morphological divergence. / Foi realizado um estudo taxonômico para a espécie Culex nigripalpus com base em análises morfológicas e moleculares, com a região "barcode" do gene COI. As análises indicaram que os indivíduos dos EUA e do Brasil não diferem entre si a ponto de inferir que compõem um complexos de espécies. Neste caso, a ampla distância geográfica não representou uma elevada divergência genética e morfológica.

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Identifying the molecular interactions of pathogens in different mosquito species is critical for understanding how mosquitoes transmit diseases. In this study, the role of the Jak-STAT immune signalling pathway in two different mosquito species, (Aedes aegypti L.) and (Culex quinquefasciatus L.) was assessed. Using in silico analysis tools, cell culture, and molecular techniques, changes in gene expression were assessed during lipopolysaccharide (LPS) challenge and West Nile virus (WNV) infection in the two species. It was found that activation of the Jak-STAT pathway occurred more quickly in Ae. aegypti cells compared to Cx. quinquefasciatus cells during LPS exposure. During WNV infections, no significant differences were observed, although preliminary evidence suggests that differential activation of the Jak-STAT pathway may exist between the two species. This research extends our understanding of the mosquito immune system while demonstrating the critical importance of vector-virus interactions across different mosquito species.