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4 resultados encontrados para: AUTOR: Ibarra Cerdeña, Carlos Napoleón
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1.
- Libro con arbitraje
Atlas de las orquídeas del Soconusco: modelos digitales de nichos ambientales entre Centro y Sudamérica / Vincenzo Bertolini, Anne Damon, Carlos Ibarra-Cerdeña
Bertolini, Vincenzo (autor) ; Damon, Anne Asbhy (autora) ; Ibarra Cerdeña, Carlos Napoleón (autor) ;
Tapachula, Chiapas, México : El Colegio de la Frontera Sur , 2016
Disponible en línea
Clasificación: EE/584.15097275 / B4
Cerrar
SIBE Campeche
14052-60 (Disponible) , ECO040006613 (Disponible)
Disponibles para prestamo: 2
Cerrar
SIBE Chetumal
ECO030008637 (Disponible) , ECO030008636 (Disponible)
Disponibles para prestamo: 2
Cerrar
SIBE San Cristóbal
ECO010018891 (Disponible) , ECO010018890 (Disponible)
Disponibles para prestamo: 2
Cerrar
SIBE Tapachula
ECO020013617 (Disponible) , ECO020013606 (Disponible) , ECO020013616 (Disponible) , ECO020013605 (Disponible)
Disponibles para prestamo: 4
Cerrar
SIBE Villahermosa
ECO050006256 (Disponible) , ECO050006255 (Disponible)
Disponibles para prestamo: 2
Resumen en español

Esta publicación tiene un doble objetivo: difundir resultados de investigación inéditos y de vanguardia acerca de la distribución de algunas especies de orquídeas neotropicales y proporcionar esta información para que sea consultada, modificada, validada empíricamente o mejorada, gracias a la entrega multimedia de los propios modelos, listos para su utilización. Por ello, se dirige a técnicos científicos, investigadores y cualquier organización que se ocupe de la conservación ambiental en general y de la conservación de la orquideoflora del neotrópico en específico, con el propósito de que se utilice la información como una valiosa herramienta para actuar en favor de la conservación de la biodiversidad.


2.
Artículo
Geographical, landscape and host associations of Trypanosoma cruzi DTUs and lineages
Izeta Alberdi, Amaia (autor) ; Ibarra Cerdeña, Carlos Napoleón (autor) ; Moo Llanes, David Alejandro (autor) ; Ramsey Willoquet, Janine M. (autor) ;
Contenido en: Parasites & Vectors Vol. 9, no. 1 (December 2016), p. 1-20 ISSN: 1756-3305
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Resumen en: Inglés |
Resumen en inglés

Background: The evolutionary history and ecological associations of Trypanosoma cruzi, the need to identify genetic markers that can distinguish parasite subpopulations, and understanding the parasite’s evolutionary and selective processes have been the subject of a significant number of publications since 1998, the year when the first DNA sequence analysis for the species was published. Methods: The current analysis systematizes and re-analyzes this original research, focusing on critical methodological and analytical variables and results that have given rise to interpretations of putative patterns of genetic diversity and diversification of T. cruzi lineages, discrete typing units (DTUs), and populations, and their associations with hosts, vectors, and geographical distribution that have been interpreted as evidence for parasite subpopulation specificities. Results: Few studies use hypothesis-driven or quantitative analysis for T. cruzi phylogeny (16/58 studies) or phylogeography (10/13). Among these, only one phylogenetic and five phylogeographic studies analyzed molecular markers directly from tissues (i.e. not from isolates). Analysis of T. cruzi DTU or lineage niche and its geographical projection demonstrate extensive sympatry among all clades across the continent and no significant niche differences among DTUs. DTU beta-diversity was high, indicating diverse host assemblages across regions, while host dissimilarity was principally due to host species turnover and to a much lesser degree to nestedness. DTU-host order specificities appear related to trophic or microenvironmental interactions. Conclusions: More rigorous study designs and analyses will be required to discern evolutionary processes and the impact of landscape modification on population dynamics and risk for T. cruzi transmission to humans.


3.
- Artículo con arbitraje
Resumen en: Inglés |
Resumen en inglés

Landscape interactions of Trypanosoma cruzi (Tc) with Triatoma dimidiata (Td) depend on the presence and relative abundance of mammal hosts. This study analyzed a landscape adjacent to the Calakmul Biosphere Reserve, composed of conserved areas, crop and farming areas, and the human community of Zoh Laguna with reported Chagas disease cases. Sylvatic mammals of the Chiroptera, Rodentia, and Marsupialia orders were captured, and livestock and pets were sampled along with T. dimidiata in all habitats. Infection by T. cruzi was analyzed using mtDNA markers, while lineage and DTU was analyzed using the mini-exon. 303 sylvatic specimens were collected, corresponding to 19 species during the rainy season and 114 specimens of 18 species during dry season. Five bats Artibeus jamaicensis, Artibeus lituratus, Sturnira lilium, Sturnira ludovici, Dermanura phaeotis (Dp) and one rodent Heteromys gaumeri were collected in the three habitats. All but Dp, and including Carollia brevicauda and Myotis keaysi, were infected with predominately TcI in the sylvatic habitat and TcII in the ecotone. Sigmodon hispidus was the rodent with the highest prevalence of infection by T. cruzi I and II in ecotone and domestic habitats. Didelphis viginiana was infected only with TcI in both domestic and sylvatic habitats; the only two genotyped human cases were TcII. Two main clades of T. cruzi, lineages I (DTU Ia) and II (DTU VI), were found to be sympatric (all habitats and seasons) in the Zoh-Laguna landscape, suggesting that no species-specific interactions occur between the parasite and any mammal host, in any habitat. We have also found mixed infections of the two principal T. cruzi clades in individuals across modified habitats, particularly in livestock and pets, and in both haplogroups of T. dimidiata.

Results are contradictory to the dilution hypothesis, although we did find that most resilient species had an important role as T. cruzi hosts. Our study detected some complex trends in parasite transmission related to lineage sorting within the matrix. Intriguingly, TcIa is dominant in terrestrial small wildlife in the sylvatic habitat and is the only parasite DTU found in D. virginiana in the domestic habitat, although its frequency remained constant in sylvatic and ecotone vectors. Bats have a key role in TcVI dispersal from the sylvatic habitat, while dogs, sheep, and humans are drivers of TcVI between domestic and ecotone habitats. Overall, our results allow us to conclude that T. cruzi transmission is dependent on host availability within a highly permeable landscape in Zoh Laguna.


4.
- Artículo con arbitraje
PDF PDF
Resumen en: Inglés |
Resumen en inglés

Triatoma dimidiata (Latreille) is a key vector complex of Trypanosoma cruzi, etiologic agent of Chagas disease, as it spans North, Central, and South America. Although morphological and genetic studies clearly indicate existence of at least five clades within the species, there has been no robust or systematic revision, or appropriate nomenclature change for species within the complex. Three of the clades (haplogroups) are distributed in Mexico, and recent evidence attests to dispersal of clades across previously “presumed” monotypic geographic regions. Evidence of niche conservatism among sister species of this complex suggests that geographic dispersal is possible for non-sympatric populations, although no information is available on the behavioural aspects of potential interclade interactions, for instance whether differentiation of chemical signaling or response to these signals could impede communication among the haplogroups. Methods: Volatiles emitted by disturbed bugs, Brindley’s (BGs), and metasternal (MGs) glands were identified using solid-phase micro-extraction (SPME) and gas chromatography coupled mass spectrometry (GC-MS). Volatile compounds emitted by BGs and MGs, and those secreted by disturbed nymphs and adults, of the three Mexican T. dimidiata haplogroups were tested for avoidance behaviour by conspecific nymphs and adults using an olfactometer.

Results: Triatoma dimidiata haplogroups all have three age-related alarm responses: absence of response by early stage nymphs, stage-specific response by 4-5th stage nymphs, and a shared 4-5th nymph and adult response to adult compounds. Disturbed bugs released 15 to 24 compounds depending on the haplogroup, among which were three pyrazines, the first report of these organoleptics in Triatominae. Isobutyric acid from BGs was the most abundant molecule in the response in all haplogroups, in addition to 15 (h1) to 21 (h2 and h3) MG compounds. Avoidance behaviour of disturbed bugs and volatiles emitted by BGs were haplogroup specific, while those from the MG were not. Conclusions: Discriminant and cluster analysis of BG + MG compounds indicate significant separation among the three haplogroups, while alarm response compounds were similar between h2 and h3, both distinct from h1. This latter haplogroup is ancestral phylogenetically to the other two. Our results suggest that alarm responses are a conserved behaviour in the Triatoma dimidiata complex.