9 research outputs found
Midgut microbiota of the malaria mosquito vector Anopheles gambiae and Interactions with plasmodium falciparum Infection
The susceptibility of Anopheles mosquitoes to Plasmodium infections relies on complex interactions between the insect vector and the malaria parasite. A number of studies have shown that the mosquito innate immune responses play an important role in controlling the malaria infection and that the strength of parasite clearance is under genetic control, but little is known about the influence of environmental factors on the transmission success. We present here evidence that the composition of the vector gut microbiota is one of the major components that determine the outcome of mosquito infections. A. gambiae mosquitoes collected in natural breeding sites from Cameroon were experimentally challenged with a wild P. falciparum isolate, and their gut bacterial content was submitted for pyrosequencing analysis. The meta-taxogenomic approach revealed a broader richness of the midgut bacterial flora than previously described. Unexpectedly, the majority of bacterial species were found in only a small proportion of mosquitoes, and only 20 genera were shared by 80% of individuals. We show that observed differences in gut bacterial flora of adult mosquitoes is a result of breeding in distinct sites, suggesting that the native aquatic source where larvae were grown determines the composition of the midgut microbiota. Importantly, the abundance of Enterobacteriaceae in the mosquito midgut correlates significantly with the Plasmodium infection status. This striking relationship highlights the role of natural gut environment in parasite transmission. Deciphering microbe-pathogen interactions offers new perspectives to control disease transmission.Institut de Recherche pour le Developpement (IRD); French Agence Nationale pour la Recherche [ANR-11-BSV7-009-01]; European Community [242095, 223601]info:eu-repo/semantics/publishedVersio
Infection state of Pantoea agglomerans in the rice water weevil Lissorhoptrus oryzophilus (Coleoptera: Curculionidae)
Estrogen- and stress-induced DNA damage in breast cancer and chemoprevention with dietary flavonoid
Sinonasal cancer
International audienceSinonasal cancer, the cancer of the nose and paranasal cavities, is rare with an incidence below 2/100,000 person-year; the incidence is lowest among women and with distinct differences between countries. These variations in incidence are mostly explained by differences in occupational exposure, in particular exposure to wood dust, which is by far the major risk factor. This chapter gives an overview of epidemiological studies on sinonasal cancer dealing with epidemiological evidence for various occupational risk factors, exposure characteristics, tumor pathology, findings from experimental and human studies contributing to understanding of cancer mechanisms, and, finally, with molecular alterations observed in sinonasal cancer tissue available as potential molecular markers. The main studies and their findings as well as the principal pathological features of sinonasal tumors are summarized in tables and exemplified in illustrations. © Springer Nature Switzerland AG 2020