Search results for "Chagas"
showing 10 items of 47 documents
ICTV Virus Taxonomy Profile: Dicistroviridae
2017
Dicistroviridae is a family of small non-enveloped viruses with monopartite, linear, positive-sense RNA genomes of approximately 8–10 kb. Viruses of all classified species infect arthropod hosts, with some having devastating economic consequences, such as acute bee paralysis virus in domesticated honeybees and taura syndrome virus in shrimp farming. Conversely, the host specificity and other desirable traits exhibited by several members of this group make them potential natural enemies for intentional use against arthropod pests, such as triatoma virus against triatomine bugs that vector Chagas disease. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on…
Microbiomes of North American Triatominae: The Grounds for Chagas Disease Epidemiology.
2018
AbstarctInsect microbiomes influence many fundamental host traits, including functions of practical significance such as their capacity as vectors to transmit parasites and pathogens. The knowledge on the diversity and development of the gut microbiomes in various blood feeding insects is thus crucial not only for theoretical purposes, but also for the development of better disease control strategies. In Triatominae (Heteroptera: Reduviidae), the blood feeding vectors of Chagas disease in South America and parts of North America, the investigation of the microbiomes is in its infancy. The few studies done on microbiomes of South American Triatominae species indicate a relatively low taxonom…
American Trypanosomiasis Chagas disease : one hundred years of research
2017
Abstract In understanding biodiversity, taxonomy and systematics work together, although the two terms are often confused. The objective of systematics is to understand the natural mechanisms responsible for the biodiversity, while the task of taxonomy is to set up a useful classification of the organisms concerned. The Triatominae (Hemiptera, Reduviidae) are the vectors of Chagas disease. Their classification faces frequent divergence between the modern concepts of systematics and the traditional, morphologically-based, classification. This chapter revises the main concepts of species in general, and their application to the Triatominae. We summarize the current classification of the vecto…
Under pressure: phenotypic divergence and convergence associated with microhabitat adaptations in Triatominae
2021
AbstractBackgroundTriatomine bugs, the vectors of Chagas disease, associate with vertebrate hosts in highly diverse ecotopes. When these blood-sucking bugs adapt to new microhabitats, their phenotypes may change. Although understanding phenotypic variation is key to the study of adaptive evolution and central to phenotype-based taxonomy, the drivers of phenotypic change and diversity in triatomines remain poorly understood.Methods/FindingsWe combined a detailed phenotypic appraisal (including morphology and morphometrics) with mitochondrialcytband nuclear ITS2 DNA-sequence analyses to studyRhodnius ecuadoriensispopulations from across the species’ range. We found three major, naked-eye phen…
Simple dialkyl pyrazole-3,5-dicarboxylates show in vitro and in vivo activity against disease-causing trypanosomatids.
2017
SUMMARYThe synthesis and antiprotozoal activity of some simple dialkyl pyrazole-3,5-dicarboxylates (compounds 2–6) and their sodium salts (pyrazolates) (compounds 7–9) against Trypanosoma cruzi, Leishmania infantum and Leishmania braziliensis are reported. In most cases the studied compounds showed, especially against the clinically significant amastigote forms, in vitro activities higher than those of the reference drugs (benznidazole for T. cruzi and glucantime for Leishmania spp.); furthermore, the low non-specific cytotoxicities against Vero cells and macrophages shown by these compounds led to good selectivity indexes, which are 8–72 times higher for T. cruzi amastigotes and 15–113 tim…
Antiprotozoal and cysteine proteases inhibitory activity of dipeptidyl enoates
2018
A family of dipeptidyl enoates has been prepared and tested against the parasitic cysteine proteases rhodesain, cruzain and falcipain-2 related to sleeping sickness, Chagas disease and malaria, respectively. They have also been tested against human cathepsins B and L1 for selectivity. Dipeptidyl enoates resulted to be irreversible inhibitors of these enzymes. Some of the members of the family are very potent inhibitors of parasitic cysteine proteases displaying k2nd (M−1s−1) values of seven orders of magnitude. In vivo antiprotozoal testing was also performed. Inhibitors exhibited IC50 values in the micromolar range against Plasmodium falciparum, Trypanosoma brucei, Trypanosoma cruzi and ev…
[1,2,3]Triazolo[1,5-a]piridinas y compuestos relacionados : aplicaciones en química supramolecular : actividad biológica
2013
Los heterociclos nitrogenados son moléculas clave dentro de numerosos campos científicos. En concreto, los triazoles han encontrado numerosas aplicaciones en química médica como antifúngicos (fluconazol, posaconazol), antidepresivos (trazodona) o anticancerígenos (triazoloacridonas). En este contexto se decidió sintetizar nuevos derivados de [1,2,3]triazolo[1,5-a]piridinas con el fin de explorar su capacidad de interaccionar con ADN y su actividad leishmanicida y antichagásica. Con este objetivo se ha utilizado la química clásica de las triazolopiridinas (reacción de litiación regioselectiva de este heterociclo, seguida de adición de un electrófilo), para obtener nuevos derivados con estruc…
Asymptomatic Leishmania infantum/chagasi infection in blood donors of western Sicily.
2007
The purpose of this study was to evaluate whether the risk of transfusion-transmitted visceral leishmaniasis was present in an area of western Sicily where the incidence of the disease is higher than the regional average. From May to December 2005, 1449 blood donors from Agrigento district (Sicily, Italy) were screened for the presence of anti-Leishmania antibodies by an indirect immunofluorescent antibody test (IFAT). Blood samples from IFAT-positive donors were examined by PCR to detect Leishmania DNA. Anti-Leishmania antibodies were found in 11 (0.75%) cases, among which Leishmania DNA was detected from four (36.4%). Particular techniques to inactivate different pathogens would be consid…
Novel [1,2,3]triazolo[1,5-a]pyridine derivatives are trypanocidal by sterol biosynthesis pathway alteration.
2019
Aim: To study a new series of [1,2,3]triazolo[1,5-α]pyridine derivatives as trypanocidal agents because current antichagasic pharmacologic therapy is only partially effective. Materials & methods: The effect of the series upon Trypanosoma cruzi epimastigotes and murine macrophages viability, cell cycle, cell death and on the metabolites of the sterol biosynthesis pathway was measured; also, docking in 14α-demethylase was analyzed. Results: Compound 16 inhibits 14α-demethylase producing an imbalance in the cholesterol/ergosterol synthesis pathway, as suggested by a metabolic control and theoretical docking analysis. Consequently, it prevented cell proliferation, stopping the cellular cy…
[Diagnostic performance of surface electrocardiogram in early detection of chagasic cardiomyopathy].
2013
Contrast-enhanced cardiac magnetic resonance imaging (CMR) allows early detection of myocardial involvement by Trypanosoma cruzi infection. The aim of our study was to assess the diagnostic performance of the surface electrocardiogram (ECG) in the early detection of Chagas' cardiomyopathy (CCM) compared with CMR.We included 43 asymptomatic patients (30 women, 42 ± 9.8 years), diagnosed of Chagas disease. The sample was divided into 2 groups according to the presence (n=17) or absence (n=26) of electrocardiographic abnormalities. All patients underwent CMR and late gadolinium enhancement (LGE) was used as a marker of early myocardial involvement.Six (14%) patients had a LGE significantly hig…