Vertical Transmission of Zika Virus (Flaviviridae, Flavivirus) in Amazonian Aedes aegypti (Diptera: Culicidae) delays egg hatching and larval development of progeny.

Zika virus (ZIKV) has emerged as a globally important arbovirus and has been reported from all states of Brazil. The virus is primarily transmitted to humans through the bite of an infective Aedes aegypti (Linnaeus, 1762) or Aedes albopictus (Skuse, 1895). However, it is important to know if ZIKV transmission also occurs from Ae. aegypti through infected eggs to her offspring. Therefore, a ZIKV and dengue virus (DENV) free colony was established from eggs collected in Manaus and maintained until the third?fourth generation in order to conduct ZIKV vertical transmission (VT) experiments which used an infectious bloodmeal as the route of virus exposure. The eggs from ZIKV-infected females were allowed to hatch. The resulting F1 progeny (larvae, pupae, and adults) were quantitative polymerase chain reaction (qPCR) assayed for ZIKV. The viability of ZIKV vertically transmitted to F1 progeny was evaluated by cultivation in C6/36 cells. The effects of ZIKV on immature development of Ae. aegypti was assessed and compared with noninfected mosquitoes. Amazonian Ae. Aegypti were highly susceptible to ZIKV infection (96.7%), and viable virus passed to their progeny via VT. Moreover, eggs from the ZIKV-infected mosquitoes had a significantly lower hatch rate and the slowest hatching. In addition, the larval development period was slower when compared to noninfected, control mosquitoes. This is the first study to illustrate VT initiated by oral infection of the parental population by using mosquitoes, which originated from the field and a ZIKV strain that is naturally circulating in-country. Additionally, this study suggests that ZIKV present in the Ae. aegypti can modify the mosquito life cycle. The data reported here suggest that VT of ZIKV to progeny from naturally infected females may have a critical epidemiological role in the dissemination and maintenance of the virus circulating in the vector

Aspecto da interação parasito hospedeiro na infecção com Schistosoma sp : imunidade inata em Biomphalaria sp. e oncogênese no hospedeiro vertebrado

Submitted by Nuzia Santos ([email protected]) on 2019-07-15T17:53:06Z No. of bitstreams: 1 T-2017_Rafael Pimenta.pdf: 8867805 bytes, checksum: f31c1d267a6f48834abec544b0b04d50 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2019-07-15T17:57:26Z (GMT) No. of bitstreams: 1 T-2017_Rafael Pimenta.pdf: 8867805 bytes, checksum: f31c1d267a6f48834abec544b0b04d50 (MD5)Made available in DSpace on 2019-07-15T17:57:26Z (GMT). No. of bitstreams: 1 T-2017_Rafael Pimenta.pdf: 8867805 bytes, checksum: f31c1d267a6f48834abec544b0b04d50 (MD5) Previous issue date: 2017Fundação Oswaldo Cruz. Instituto René Rachou. Belo Horizonte, MG, Brasil.Atualmente existem cerca de 200 milhões de pessoas infectadas em 74 países com uma das cinco espécies de Schistosoma sp. A compatibilidade entre o parasito e o hospedeiro intermediário tem como componente fundamental o sistema de defesa interno do caramujo, fato este que determina a susceptibilidade ou a resistência à infecção. Este estudo avaliou a resposta do processo de infecção de B. glabrata “primados” (infectados por S. mansoni e curados por quimioterapia) e reinfectados. Avaliou-se se a hemolinfa de caramujos primados atuam em caramujos normais após infecção, através da transferência da hemolinfa. Também analisou-se como linhagens de células epiteliais humanas do fígado e da ureta reagem a ovos de S. mansoni e S. haematobium. A resposta dos hemócitos e fatores solúveis de B. glabrata primados contra os esporocistos teve uma predominância de esporocistos em comparação com os exemplares controle (infectados uma vez). Quando a hemolinfa de B. glabrata primados foi transferida para caramujos normais, a quantidade de cercarias liberadas foi menor após 5 semanas comparando com o controle. Já na 6 semanas após a infecção, os caramujos que receberam a hemolinfa de B. glabrata tiveram o número de cercárias reduzido. Porém, o grupo de B. glabrata que recebeu hemolinfa primado continuou liberando menos cercárias. A resposta contra S. mansoni ocorreu de forma mais rápida quando se transferiu hemolinfa de B. glabrata primados, após re-infecção por S. mansoni. Nossos resultados mostram pela primeira vez uma imunidade parcial em B. glabrata completamente curados de uma infecção primária e infectados novamente. A outra parte do estudo mostra a indução de crescimento de ovos de S. mansoni e S. haematobium com linhagens de células humanas e a análise de expressão gênica após contato inicial (2h) e contato prolongado (24h) das células com os ovos. Observamos que ambas as espécies estimulam crescimento celular em linhagens de células epiteliais da ureta causando morte celular em linhagens de células de colangiócitos. Os ovos de S. mansoni induziram a via de sinalização do câncer coloretal no tempo de 2 h após interação com as células urotelias. No tempo de 24 h ambas as espécies causaram a inibição da via de supressor de tumor P53. Porém, os genes responsáveis por essa inibição variaram dependendo da espécie de Schistosoma. Nos colangiócitos foi observado a morte das células após a interação com os ovos. Os resultados mostram que a resposta proliferativa ou o declínio de crescimento é influenciado não somente pela espécie de Schistosoma mas também pela origem de células epiteliais.There are currently about 200 million people infected in 74 countries with one of five species of Schistosoma sp. The compatibility between the parasite and the intermediate host has as its fundamental component the internal defense system of the snail, a fact that determines the susceptibility or resistance to infection. This study evaluated the response of the infection process of "primed" B. glabrata (infected with S. mansoni and cured by chemotherapy) and reinfected. It was evaluated whether the hemolymph of primate snails act on normal snails after infection, by transferring hemolymph. We also analyzed how human epithelial cell lines from the liver and urethra react to S. mansoni and S. haematobium eggs. The response of hemocytes and soluble factors of B. glabrata against sporocysts had a predominance of sporocysts compared to control (infected only once). When the hemolymph of primed B. glabrata was transferred to normal snails, the amount of cercariae released was lower after 5 weeks compared to the control. As early as 6 weeks after infection, the snails that received the hemolymph of B. glabrata had a reduced number of cercariae. However, the group of B. glabrata that received hemolymph primate continued to release less cercariae. The response to S. mansoni occurred more rapidly when transferring hemolymph from primed B. glabrata after re-infection by S. mansoni. Our results show for the first time a partial immunity in B. glabrata completely cured from a primary infection and infected again. The other part of the study shows the induction of growth of S. mansoni and S. haematobium eggs with human cell lines and the analysis of gene expression after initial contact (2h) and prolonged contact (24h) of the cells with the eggs. We observed that both species stimulate cell growth in urethra epithelial cell lines causing cell death in the cell lines. S. mansoni eggs induced the colorectal cancer signaling pathway at 2 h after interaction with urothelial cells. At the time of 24 h both species caused inhibition of the P53 tumor suppressor pathway. However, the genes responsible for this inhibition varied depending on the species of Schistosoma. Cholangiocytes were observed to kill the cells after interaction with the eggs. The results show that the proliferative response or the growth decline is influenced not only by the Schistosoma species but also by the origin of epithelial cells

Anti-Plasmodium Activity of Angiotensin II and Related Synthetic Peptides

Plasmodium species are the causative agents of malaria, the most devastating insect-borne parasite of human populations. Finding and developing new drugs for malaria treatment and prevention is the goal of much research. Angiotensins I and II (ang I and ang II) and six synthetic related peptides designated Vaniceres 1-6 (VC1-VC6) were assayed in vivo and in vitro for their effects on the development of the avian parasite, Plasmodium gallinaceum. Ang II and VC5 injected into the thoraces of the insects reduced mean intensities of infection in the mosquito salivary glands by 88 % and 76%, respectively. Although the mechanism(s) of action is not completely understood, we have demonstrated that these peptides disrupt selectively the P.gallinaceum cell membrane. Additionally, incubation in vitro of sporozoites with VC5 reduced the infectivity of the parasites to their vertebrate host. VC5 has no observable agonist effects on vertebrates, and this makes it a promising dru

Schistosoma mansoni in susceptible and resistant snail strains Biomphalaria tenagophila: in vivo tissue response and in vitro hemocyte interactions.

Schistosomiasis is a parasitic disease that is highly prevalent, especially in developing countries. Biomphalaria tenagophila is an important invertebrate host of Schistosoma mansoni in Brazil, with some strains (e.g. Cabo Frio) being highly susceptible to the parasite, whereas others (e.g. Taim) are completely resistant to infection. Therefore, B. tenagophila is an important research model for studying immune defense mechanisms against S. mansoni. The internal defense system (IDS) of the snail comprises hemocytes and hemolymph factors acting together to recognize self from non-self molecular patterns to eliminate the threat of infection. We performed experiments to understand the cellular defenses related to the resistance and/or susceptibility of B. tenagophila to S. mansoni. During the early stages of infection, fibrous host cells of both snail strains were arranged as a thin layer surrounding the sporocysts. However, at later stages of infection, the cellular reactions in resistant snails were increasingly more intense, with thicker layers surrounding the parasites, in contrast to susceptible strains. All parasites were damaged or destroyed inside resistant snails after 10 h of infection. By contrast, parasites inside susceptible snails appeared to be morphologically healthy. We also performed experiments using isolated hemocytes from the two strains interacting with sporocysts. Hemocyte attachment started as early as 1 h after initial infection in both strains, but the killing of sporocysts was exclusive to hemocytes from the resistant strain and was time course dependent. The resistant strain was able to kill all sporocysts. In conclusion, our study revealed important aspects of the initial process of infection related to immune defense responses of strains of B. tenagophila that were resistant to S. mansoni compared with strains that were susceptible. Such information is relevant for the survival or death of the parasites and so is important in the development of control measures against this parasite

Schistosoma mansoni in susceptible and resistant snail strains Biomphalaria tenagophila: in vivo tissue response and in vitro hemocyte interactions

Submitted by Nuzia Santos ([email protected]) on 2014-06-06T16:44:11Z No. of bitstreams: 1 Schistosoma mansoni in susceptible and resistant snail strains Biomphalaria tenagophila.pdf: 2901781 bytes, checksum: 96c4b0f3ef87d7b200bb246bbdd16ad7 (MD5)Made available in DSpace on 2014-06-06T16:44:12Z (GMT). No. of bitstreams: 1 Schistosoma mansoni in susceptible and resistant snail strains Biomphalaria tenagophila.pdf: 2901781 bytes, checksum: 96c4b0f3ef87d7b200bb246bbdd16ad7 (MD5) Previous issue date: 2012Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Entomologia Médica. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Esquistossomose. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Entomologia Médica. Belo Horizonte, MG, BrasilUniversidade Federal de Sergipe. Laboratório de Entomologia e Parasitologia Tropical. Aracajú, SE, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Entomologia Médica. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Esquistossomose. Belo Horizonte, MG, BrasilSchistosomiasis is a parasitic disease that is highly prevalent, especially in developing countries. Biomphalaria tenagophila is an important invertebrate host of Schistosoma mansoni in Brazil, with some strains (e.g. Cabo Frio) being highly susceptible to the parasite, whereas others (e.g. Taim) are completely resistant to infection. Therefore, B. tenagophila is an important research model for studying immune defense mechanisms against S. mansoni. The internal defense system (IDS) of the snail comprises hemocytes and hemolymph factors acting together to recognize self from non-self molecular patterns to eliminate the threat of infection. We performed experiments to understand the cellular defenses related to the resistance and/or susceptibility of B. tenagophila to S. mansoni. During the early stages of infection, fibrous host cells of both snail strains were arranged as a thin layer surrounding the sporocysts. However, at later stages of infection, the cellular reactions in resistant snails were increasingly more intense, with thicker layers surrounding the parasites, in contrast to susceptible strains. All parasites were damaged or destroyed inside resistant snails after 10 h of infection. By contrast, parasites inside susceptible snails appeared to be morphologically healthy. We also performed experiments using isolated hemocytes from the two strains interacting with sporocysts. Hemocyte attachment started as early as 1 h after initial infection in both strains, but the killing of sporocysts was exclusive to hemocytes from the resistant strain and was time course dependent. The resistant strain was able to kill all sporocysts. In conclusion, our study revealed important aspects of the initial process of infection related to immune defense responses of strains of B. tenagophila that were resistant to S. mansoni compared with strains that were susceptible. Such information is relevant for the survival or death of the parasites and so is important in the development of control measures against this parasite

Developmental biology of the Brazilian ‘Armed’ spider Phoneutria nigriventer (Keyserling, 1891): Microanatomical and molecular analysis of the embryonic stages

Submitted by Nuzia Santos ([email protected]) on 2015-01-07T15:57:56Z No. of bitstreams: 1 Developmental biology of the Brazilian Armed spider Phoneutria nigriventer (Keyserling, 1891).pdf: 1650087 bytes, checksum: 8b1cd36df9ed709b2f1716264889b9b2 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2015-01-07T16:04:51Z (GMT) No. of bitstreams: 1 Developmental biology of the Brazilian Armed spider Phoneutria nigriventer (Keyserling, 1891).pdf: 1650087 bytes, checksum: 8b1cd36df9ed709b2f1716264889b9b2 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2015-01-07T16:09:20Z (GMT) No. of bitstreams: 1 Developmental biology of the Brazilian Armed spider Phoneutria nigriventer (Keyserling, 1891).pdf: 1650087 bytes, checksum: 8b1cd36df9ed709b2f1716264889b9b2 (MD5)Made available in DSpace on 2015-01-07T16:09:20Z (GMT). No. of bitstreams: 1 Developmental biology of the Brazilian Armed spider Phoneutria nigriventer (Keyserling, 1891).pdf: 1650087 bytes, checksum: 8b1cd36df9ed709b2f1716264889b9b2 (MD5) Previous issue date: 2011Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratorio de Entomologia médica. Belo Horizonte, MG, Brasil /Universidade Federal de Minas Gerais. Departamento de Morfologia. Belo Horizonte, MG, Brasil/Fundação Ezequiel Dias. Centro de Pesquisa e Desenvolvimento. Belo Horizonte, MG, BrasilFundação Ezequiel Dias. Centro de Pesquisa e Desenvolvimento. Belo Horizonte, MG, BrasilFundação Ezequiel Dias. Centro de Pesquisa e Desenvolvimento. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratorio de Entomologia médica. Belo Horizonte, MG, Brasil/Universidade de Montes Claros. Montes Claros, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratorio de Entomologia médica. Belo Horizonte, MG, BrasilFundação Ezequiel Dias. Centro de Pesquisa e Desenvolvimento. Belo Horizonte, MG, BrasilFundação Ezequiel Dias. Centro de Pesquisa e Desenvolvimento. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Laboratorio de Entomologia médica. Belo Horizonte, MG, Brasil/Universidade Federal de Minas Gerais. Departamento de Morfologia. Belo Horizonte, MG, BrasilPhoneutria (Ctenidae) is among the most dangerous venomous spiders in Brazil. Its venom is composed of a mixture of pharmacologically active components, some of which have been quite extensively studied due to their potentiality as models for new pharmaceutical drugs. Nevertheless, literature data on the venom-producing glands are very limited. In the present study, we follow the biological development of intra-cocoon stages of Phoneutria nigriventer spiders, mainly regarding the formation of the venomous apparatus and venom production. The results showed that the venom glands of Phoneutria are already present in the early 1st pre-larva stage. The venomous apparatus is completely formed in the larva, a stage that precedes the spider eclosion from the cocoon. At embryo stages, transcripts of a vertebrate-active neurotoxin (PhTx1) were shown to be present, as well as, unidentified venom proteins that were immunolabeled by anti-venom antibodies. It seems that venom toxins play roles in the protection and survival of those early developmental stages of Phoneutria spiders

Histological sections showing distinct views of <i>S. mansoni</i> sporocysts.

<p>(<b>A</b>) Longitudinal section of the sporocyst medial plane showing the main internal organelles: germinal cells (gc), neural mass (nm), terebratorium (t) and several vesicles (v). The two dotted lines delimit the anterior (A) and posterior (P) regions of the parasite. (<b>B</b>) Transversal section of the anterior region of the parasite showing the gc. (<b>C</b>) Transversal section of the posterior region of the parasite, showing several types of v. (<b>D</b>) Oblique section of the anterior region of the parasite, showing the t, gc and nm. (<b>E</b>) Oblique sequential section of the anterior region of the parasite showing the large area of the t, as well as the apical glands (ag) and gc. Magnification 40X.</p

Interaction between hemocytes from the <i>B. tenagophila</i> Taim strain and <i>S. mansoni</i> sporocysts.

<p>(<b>A</b>) After 1 h of interaction, showing a sporocyst with normal morphology and no attached hemocyte. Various germinal cells are present (white arrows). Magnification 40X. (<b>B,C</b>) After 1 h of interaction, showing sporocysts with a few attached hemocytes (arrowheads). ‘h’ indicates free hemocytes. Magnification 40X. (<b>D,E</b>) After 5 h of interaction, showing porocysts with several attached (arrowheads) and free h. There is also a great quantity of cellular debris (arrows). Magnification 40X. (<b>F,G</b>) After 10 h of interaction, several attached hemocytes (arrowheads) are seen on the sporocyst. The parasite morphology is showing disturbance of the internal organelles (asterisks). Cellular debris can also be seen (arrows). Magnification 40X. (<b>H</b>) After 10 h of interaction detailing the anterior region of the sporocyst. There is a hemocyte adhered to the surface (arrowheads) and the disarrangement of the syncytial layer on the surface of the parasite. Magnification 63X. (<b>I</b>,<b>J</b>) After 10 h of interaction. sporocysts with a few attached hemocytes (arrowheads) can be seen, as well as a large amount of cellular debris around the parasite (arrows). The sporocyst in (J) is completely destroyed and is now in several parts (asterisks). Magnification 40X.</p

Histological sections of uninfected host <i>B. tenagophila</i> (control).

<p>(<b>A</b>) General view of the heat-foot region of <i>B. tenagophila</i>. Observe the mouth (Mo) near the anterior region (A), posterior region (P) and the mantle (m) that covers the heat-foot region (Cr). Magnification 2.5X. (<b>B</b>) Details of the region between the cr and the m. The lateral m region shows several types of vesicle (v) with distinct stain densities. Magnification 40X. (<b>C</b>) Details of the heat-foot region. Observe the ciliar cylindrical epithelium (Ep) and just below it the dense connective tissue (Ct) that is supported by the muscular connective tissue (Mt) comprising a network of muscle fibers (white arrow). A large crypt is seen that is similar to a large epithelial fold (large arrow). Small arrows indicate the cilia. Magnification 100X. (<b>D</b>) Detail of the heat-foot region, showing the Ep with several crypts (arrows) and moat-like invaginations. Key: Ct, connective tissue; Mt, muscle tissue; arrows, muscle fibers; arrowheads, crypts. Magnification: 40X. (<b>E</b>) Large magnification showing details of one crypt (large arrow) deep into the Ep. Details of the cilia on the epithelium are shown (arrowheads) Magnification: 100X. (<b>F</b>) Posterior area of the heat-foot region. Notice the presence of numerous v in the Ct supported by Mt. The Ep shows several crypts (arrowheads) Magnification 40X.</p