The process of domestication in Triatominae

International audienc

Wing symmetry and flight activity

We compared bilateral structures (wings) of flying versus non-flying insects in two lines of #P. megistus$ which differed only by their laboratory maintenance time : PM1 (more than five generations in insectarium) and PM2 (one or two generations under laboratory conditions). Insects were processed according to Schofield (1980) and observed through a period of 30 days. During this time the insects that had flight (gf, for "good" flyers) and their wings extracted for morphometry. At the end of this period the same number of insects that did not fly (bf, for "bad" flyers), were used as a control and submitted to the same analysis. Fluctuating asymmetry (FA) was estimated at nine distances (A, B, C, D, E, H, 1, 2 and 3). FA occurs as a result of random deviations in the developement of bilaterally symmetric traits, and is considered as a useful trait for monitoring stress in the laboratory and in natural environments (Parsons, 1990). For each sample, FA values were calculated for each character as the sum of the squared signed differences between sides divided by the number of individuals sampled, i.e., ((Li-Ri)2)/N). This is equivalent to index 5 of Palmer and Strobek (1986) which they state is best able to discriminate true differences in FA. As the index to estimate asymmetry is a variance, differences between samples were tested for significance using tests of homogeneity of variances (Ho : s1=s2). Due to low sample size, statistical analysis was not applied to PM2 females (only two individuals). The PM1 bf females (6 insects) were more asymmetric than their gf counterparts (5 insects) at four wings traits (2,3 in PM1 and 2 in PM2) (gf=7 insects and bf=7 insects). Conversely, one character out of nine was found more asymmetric in gf either from PM1 (character 3 for PM1 females and E for PM1 males) or PM2 males (character D). (Résumé d'auteur

Observational study of adherence to European clinical practice guidelines for the management of acute coronary syndrome in revascularized versus non-revascularized patients – the CONNECT Study

SummaryBackgroundThe CONNECT study compared clinician adherence to guideline-recommended secondary prevention therapies prescribed at discharge for patients hospitalized for acute coronary syndrome (ACS) in those managed initially with percutaneous coronary intervention (PCI; revascularized) and those who did not undergo revascularization.MethodsPatients aged greater than or equal to 18 years, hospitalized for a documented ST-segment elevation or non-ST-segment elevation ACS, were enrolled consecutively over 1 month at 238 sites in France.ResultsCompared with revascularized patients (n=870), non-revascularized patients (n=706) were significantly older, and a greater proportion were women, had high-blood pressure, type-2 diabetes or a history of atherothrombotic or cardiac disease, but a smaller proportion had a history of coronary angioplasty. On discharge, non-revascularized patients were prescribed beta-blockers, aspirin, statins, angiotensin-converting enzyme inhibitors or adenosine diphosphate receptor antagonists less frequently than revascularized patients. An adherence score greater than or equal to 80% (at least four of the five recommended agents prescribed at discharge) was found in 96.7% of revascularized patients and 74.4% of non-revascularized patients (P<0.001).ConclusionsDespite a similar or even higher level of cardiovascular risk, non-revascularized ACS patients were prescribed guideline-recommended secondary prevention therapy less frequently than revascularized patients

Cambios morfométricos de Triatoma flavida Neiva, 1911 (Hemiptera:Triatominae) que ocurrieron cuando fueron llevados desde su hábitat selvático al laboratorio

The one-generational metric changes occurring in Triatoma flavida (Hemiptera: Triatominae) when carried from its wild habitat (caves) to laboratory, were examined using traditional morphometric techniques. As for other species of Triatoma, Rhodnius or Panstrongylus studied in similar conditions, a significant reduction of head, thorax and wing size was observed. Sexual dimorphism of the wings, while present in the wild sample, was not detected anymore in the laboratory individuals. Biological significance and epidemiological importance are discussed.Fueron examinados los cambios morfométricos que ocurrieron en la primera generación de Triatoma flavida cuando fueron llevados desde su hábitat selvático (cuevas) al laboratorio, mediante el uso de técnicas morfométricas tradicionales. Se observó una reducción significativa del tamaño de la cabeza, tórax y alas, como ocurre en otras especies de Triatoma, Rhodnius o Panstrongylus estudiados en condiciones similares. El dimorfismo sexual de tamaño en las alas, aunque presente en los individuos selváticos, no se detectó en los de laboratorio. La significación biológica y la importancia epidemiológica son discutidas

Inter-relation of sylvatic and domestic transmission of Trypanosoma cruzi in areas with and without domestic vectorial transmission in Minas Gerais, Brazil

During the period 1980-1986, we captured triatomine bugs and mammalian reservoir hosts from sylvatic and domestic situations in different municipalities of the State of Minas Gerais. Trypanosoma cruzi was isolated from captured bugs, mammals and patients. After cultivation in LIT medium, the electrophoretic enzyme profiles were determined. We obtained a total of 32 parasite isolates from regions with active domestic transmission, and 24 isolates from areas under control. For the first areas the results suggest introduction of T. cruzi from sylvatic habitats, through incursion of infected opossums and/or sylvatic T. sordida, which appears to have given rise to at least one acute human infection. Of particular interest is the finding of sylvatic opossums and a T. sordida nymph infected with ZB, that could indicate return of parasites from chronic human infections to sylvatic transmission cycles. For the areas under control we also interpret the results as interaction between sylvatic and domestic cycles of transmission, here through the invasion of houses by bugs carrying the Z1 zymodeme from the sylvatic environment. The Multivariate Correspondence Analysis gives a spatial description between the different parasite isolates and confirms the existence of a bridge in the opposite direction in the region with active vectorial transmission including the exporting of Z2 through the peridomestic environment into the sylvatic cycle. For the other areas this bridge corresponds especially to Panstrongylus megistus, importing Z1 into the domestic environment

Evolutionary and geographical history of the Leishmania donovani complex with a revision of current taxonomy.

Leishmaniasis is a geographically widespread severe disease, with an increasing incidence of two million cases per year and 350 million people from 88 countries at risk. The causative agents are species of Leishmania, a protozoan flagellate. Visceral leishmaniasis, the most severe form of the disease, lethal if untreated, is caused by species of the Leishmania donovani complex. These species are morphologically indistinguishable but have been identified by molecular methods, predominantly multilocus enzyme electrophoresis. We have conducted a multifactorial genetic analysis that includes DNA sequences of protein-coding genes as well as noncoding segments, microsatellites, restriction-fragment length polymorphisms, and randomly amplified polymorphic DNAs, for a total of approximately 18,000 characters for each of 25 geographically representative strains. Genotype is strongly correlated with geographical (continental) origin, but not with current taxonomy or clinical outcome. We propose a new taxonomy, in which Leishmania infantum and L. donovani are the only recognized species of the L. donovani complex, and we present an evolutionary hypothesis for the origin and dispersal of the species. The genus Leishmania may have originated in South America, but diversified after migration into Asia. L. donovani and L. infantum diverged approximately 1 Mya, with further divergence of infraspecific genetic groups between 0.4 and 0.8 Mya. The prevailing mode of reproduction is clonal, but there is evidence of genetic exchange between strains, particularly in Africa