Transcriptional cellular responses in midgut tissue of Aedes aegypti larvae following intoxication with Cry11Aa toxin from Bacillus thuringiensis

BACKGROUND: Although much is known about the mechanism of action of Bacillus thuringiensis Cry toxins, the target tissue cellular responses to toxin activity is less understood. Previous transcriptomic studies indicated that significant changes in gene expression occurred during intoxication. However, most of these studies were done in organisms without a sequenced and annotated reference genome. A reference genome and transcriptome is available for the mosquito Aedes aegypti, and its importance as a disease vector has positioned its biological control as a primary health concern. Through RNA sequencing we sought to determine the transcriptional changes observed during intoxication by Cry11Aa in A. aegypti and to analyze possible defense and recovery mechanisms engaged after toxin ingestion. RESULTS: In this work the changes in the transcriptome of 4(th) instar A. aegypti larvae exposed to Cry11Aa toxin for 0, 3, 6, 9, and 12 h were analyzed. A total of 1060 differentially expressed genes after toxin ingestion were identified with two bioconductoR packages: DESeq2 and EdgeR. The most important transcriptional changes were observed after 9 or 12 h of toxin exposure. GO enrichment analysis of molecular function and biological process were performed as well as Interpro protein functional domains and pBLAST analyses. Up regulated processes include vesicular trafficking, small GTPase signaling, MAPK pathways, and lipid metabolism. In contrast, down regulated functions are related to transmembrane transport, detoxification mechanisms, cell proliferation and metabolism enzymes. Validation with RT-qPCR showed large agreement with Cry11Aa intoxication since these changes were not observed with untreated larvae or larvae treated with non-toxic Cry11Aa mutants, indicating that a fully functional pore forming Cry toxin is required for the observed transcriptional responses. CONCLUSIONS: This study presents the first transcriptome of Cry intoxication response in a fully sequenced insect, and reveals possible conserved cellular processes that enable larvae to contend with Cry intoxication in the disease vector A. aegypti. We found some similarities of the mosquito responses to Cry11Aa toxin with previously observed responses to other Cry toxins in different insect orders and in nematodes suggesting a conserved response to pore forming toxins. Surprisingly some of these responses also correlate with transcriptional changes observed in Bti-resistant and Cry11Aa-resistant mosquito larvae. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-2240-7) contains supplementary material, which is available to authorized users

Socio-Economic Variations Determine the Clinical Presentation, Aetiology and Outcome of Infective Endocarditis: a Prospective Cohort Study from the ESC-EORP EURO-ENDO (European Infective Endocarditis) Registry

Background: Infective endocarditis (IE) is a life-threatening disease associated with high mortality and morbidity worldwide. We sought to determine how socio-economic factors might influence its epidemiology, clinical presentation, investigation and management, and outcome, in a large international multi-centre registry. Methods: The EurObservationalProgramme (EORP) of the European Society of Cardiology (ESC) EURO-ENDO registry comprises a prospective cohort of 3113 adult patients admitted for IE in 156 hospitals in 40 countries between January 2016 and March 2018. Patients were separated in 3 groups, according to World Bank economic stratification (Group 1 - high income [75.6%]; Group 2 - upper-middle income [15.4%]; Group 3 - lower-middle income [9.1%]). Results: Group 3 patients were younger (median age [IQR]: Group 1 - 66 [53-75] years; Group 2 - 57 [41-68] years; Group 3 - 33 [26-43] years; p<0.001) with a higher frequency of smokers, intravenous drug use and human immunodeficiency virus (HIV) infection (all p<0.001) and presented later (median [IQR) days since symptom onset: Group 1 - 12 [3-35]; Group 2 - 19 [6-54]; Group 3 - 31 [12-62]; p<0.001) with a higher likelihood of developing congestive heart failure (13.6%; 11.1%; and 22.6%, respectively; p<0.001) and persistent fever (9.8%; 14.2%; 27.9%; p<0.001). Among 2157 (69.3%) patients with theoretical indication for cardiac surgery, surgery was performed less frequently in Group 3 patients (75.5%, 76.8% and 51.3%, respectively p<0.001) who also demonstrated the highest mortality (15.0%, 23.0% and 23.7%, respectively; p<0.001). Conclusions: Socio-economic factors influence the clinical profile of patients presenting with IE across the world. Despite younger age, patients from the poorest countries presented with more frequent complications and higher mortality associated with delayed diagnosis and lower use of surgery