Molecular characterization of midgut microbiota of Aedes albopictus and Aedes aegypti from Arunachal Pradesh, India.

BACKGROUND: Microbiota inhabiting midguts of mosquitoes play a key role in the host - parasite interaction and enhance vectorial capacity of viral diseases like dengue and chikungunya fevers. Mosquito midgut is considered to be an important site for host-pathogen interaction and pathogen survival is thought to be an outcome of this interaction. In the present study we examined the bacterial community in the midgut of Aedes mosquitoes in Arunanchal Pradesh, India, a subtropical zone where dengue fever is reported to be emerging. METHOD: Larvae and pupa of Aedes mosquitoes were collected from a biodiversity hotspot, Bhalukpong, Arunachal Pradesh, India. 16S rRNA gene sequences were used for identification of isolated bacterial population from each species of mosquitoes. We used various diversity indices to assess the diversity and richness of the bacterial isolates in both mosquito species. RESULT: On the basis of 16S rRNA gene sequence analysis a total of 24 bacterial species from 13 genera were identified belonging to 10 families of four major phyla. Phylum Proteobacteria was dominant followed by Firmicutes, Bacteroidetes and Actinobacteria. The midgut bacteria belonging to the phylum Proteobacteria and Firmicutes were isolated from both Ae. albopictus and Ae. aegypti, whereas, bacteria belonging to phylum Bacteroidetes and Actinobacteria were isolated only from Ae. albopictus and Ae. aegypti respectively. Enterobacter cloacae was the dominant bacterial species in both Ae. albopictus (33.65%) and Ae. aegypti (56.45%). Bacillus aryabhattai (22.78%) was the second most common bacterial species in Ae. albopictus whereas, in Ae. aegypti the second most common bacterial species was Stenotrophomonas maltophilia (7.44%). CONCLUSION: The family Enterobacteriaceae of phylum Proteobacteria was dominant in both species of Aedes mosquitoes. To the best of our knowledge, this is the first attempt to study midgut microbiota from a biodiversity hotspot in Northeastern India. Some bacterial genera Enterobacter and Acinetobacter isolated in this study are known to play important roles in parasite-vector interaction. Information on midgut microflora may lead towards the development of novel, safe, and effective strategies to manipulate the vectorial capacity of mosquitoes.

Hepatitis viruses and non-Hodgkin's lymphoma: A review.

Non-Hodgkin's lymphoma (NHL) is among the haematological malignancies with high prevalence worldwide, causing estimated 355 900 new cases and 191 400 deaths in 2008. High prevalence of NHL is documented in economically more developed areas while low prevalence is observed in less developed areas of the globe. A wide array of environmental factors have been reported to be either directly involved or in modifying the risk of NHL development. In addition to these factors, a number of infectious agents, chiefly viruses have also been implicated in the development of NHL. This article reviews the available literature to discuss the role of hepatitis viruses in NHL development, possible mechanisms of lymphomagenesis and also identify the areas in which further research is required to better understand this disease. A brief discussion on the clinical aspects such as classification, staging, treatment approaches have also been included in this article.