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1.
Parasit Vectors ; 17(1): 145, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38500121

ABSTRACT

BACKGROUND: Triatoma garciabesi, a potential vector of the parasitic protozoan Trypanosoma cruzi, which is the causative agent of Chagas disease, is common in peridomestic and wild environments and found throughout northwestern and central Argentina, western Paraguay and the Bolivian Chaco. Genetic differentiation of a species across its range can help to understand dispersal patterns and connectivity between habitats. Dispersal by flight is considered to be the main active dispersal strategy used by triatomines. In particular, the morphological structure of the hemelytra is associated with their function. The aim of this study was to understand how genetic diversity is structured, how morphological variation of dispersal-related traits varies with genetic diversity and how the morphological characteristics of dispersal-related traits may explain the current distribution of genetic lineages in this species. METHODS: Males from 24 populations of T. garciabesi across its distribution range were examined. The cytochrome c oxidase I gene (coI) was used for genetic diversity analyses. A geometric morphometric method based on landmarks was used for morpho-functional analysis of the hemelytra. Centroid size (CS) and shape of the forewing, and contour of both parts of the forewing, the head and the pronotum were characterised. Length and area of the forewing were measured to estimate the aspect ratio. RESULTS: The morphometric and phylogenetic analysis identified two distinct lineages, namely the Eastern and Western lineages, which coincide with different ecological regions. The Eastern lineage is found exclusively in the eastern region of Argentina (Chaco and Formosa provinces), whereas the Western lineage is prevalent in the rest of the geographical range of the species. CS, shape and aspect ratio of the hemelytra differed between lineages. The stiff portion of the forewing was more developed in the Eastern lineage. The shape of both portions of the hemelytra were significantly different between lineages, and the shape of the head and pronotum differed between lineages. CONCLUSIONS: The results provide preliminary insights into the evolution and diversification of T. garciabesi. Variation in the forewing, pronotum and head is congruent with genetic divergence. Consistent with genetic divergence, morphometry variation was clustered according to lineages, with congruent variation in the size and shape of the forewing, pronotum and head.


Subject(s)
Chagas Disease , Triatoma , Male , Animals , Phylogeny , Insect Vectors , Genetic Variation
2.
Folia Parasitol (Praha) ; 702023 Apr 04.
Article in English | MEDLINE | ID: mdl-37114794

ABSTRACT

Spirometra Faust, Campbell et Kellogg, 1929 is a genus of cestodes belonging to the family Diphyllobothriidae. To date, amphibians, reptiles, and mammals are known second intermediate hosts of these parasites; humans can also be infected (the zoonotic disease is known as sparganosis or spirometrosis). Although the number of phylogenetic studies on Spirometra spp. has increased worldwide in recent years, there are few in South America. Specifically in Uruguay, molecular studies have shown that tapeworms of S. decipiens (Diesing, 1850) complexes 1 and 2 are present in this country. In this study, we characterised the larvae of Spirometra present in the annual fish Austrolebias charrua Costa et Cheffe. Phylogenetic analysis of the cytochrome c oxidase subunit I (COI) sequences of these larvae showed that they belong to S. decipiens complex 1. This is the first report of teleost fishes serving as a second intermediate host for tapeworms of the genus Spirometra in nature.


Subject(s)
Cestoda , Cestode Infections , Spirometra , Animals , Humans , Spirometra/genetics , Phylogeny , Cestode Infections/veterinary , Cestode Infections/parasitology , Fishes , Mammals
3.
Front Genet ; 13: 903683, 2022.
Article in English | MEDLINE | ID: mdl-35795213

ABSTRACT

The term Annual killifish describes a short-lived and amazing group of vertebrates inhabiting temporary ponds exposed to an extremely variable environment during its short lifespan in South America and Africa, leading to the death of the entire adult population during the dry season. Austrolebias is a specious genus of the family Rivulidae, with ∼58 currently recognized species, extensively distributed in the temperate Neotropical region. Herein, we reviewed different aspects of the evolutionary biology with emphasis on the genome dynamic linked to the burst speciation process in this genus. Austrolebias constitutes an excellent model to study the genomic evolutionary processes underlying speciation events, since all the species of this genus analyzed so far share an unusually large genome size, with an average DNA content of 5.95 ± 0.45 picograms per diploid cell (mean C-value of about 2.98 pg). The drastic nuclear DNA-increasing would be associated with a considerable proportion of transposable elements (TEs) found in the Austrolebias genomes. The genomic proportion of the moderately repetitive DNA in the A. charrua genome represents approximately twice (45%) the amount of the repetitive components of the highly related sympatric and syntopic rivulinae taxon Cynopoecilus melanotaenia (25%), as well as from other rivulids and actinopterygian fish. These events could explain the great genome instability, the high genetic diversity, chromosome variability, as well as the morphological diversity in species of Austrolebias. Thus, species of this genus represent new model systems linking different evolutionary processes: drastic genome increase, massive TEs genomic representation, high chromosome instability, occurrence of natural hybridization between sister species, and burst speciation events.

4.
BMC Genomics ; 22(1): 150, 2021 Mar 02.
Article in English | MEDLINE | ID: mdl-33653268

ABSTRACT

BACKGROUND: The irruption of Next-generation sequencing (NGS) and restriction site-associated DNA sequencing (RAD-seq) in the last decade has led to the identification of thousands of molecular markers and their genotyping for refined genomic screening. This approach has been especially useful for non-model organisms with limited genomic resources. Many building-loci pipelines have been developed to obtain robust single nucleotide polymorphism (SNPs) genotyping datasets using a de novo RAD-seq approach, i.e. without reference genomes. Here, the performances of two building-loci pipelines, STACKS 2 and Meyer's 2b-RAD v2.1 pipeline, were compared using a diverse set of aquatic species representing different genomic and/or population structure scenarios. Two bivalve species (Manila clam and common edible cockle) and three fish species (brown trout, silver catfish and small-spotted catshark) were studied. Four SNP panels were evaluated in each species to test both different building-loci pipelines and criteria for SNP selection. Furthermore, for Manila clam and brown trout, a reference genome approach was used as control. RESULTS: Despite different outcomes were observed between pipelines and species with the diverse SNP calling and filtering steps tested, no remarkable differences were found on genetic diversity and differentiation within species with the SNP panels obtained with a de novo approach. The main differences were found in brown trout between the de novo and reference genome approaches. Genotyped vs missing data mismatches were the main genotyping difference detected between the two building-loci pipelines or between the de novo and reference genome comparisons. CONCLUSIONS: Tested building-loci pipelines for selection of SNP panels seem to have low influence on population genetics inference across the diverse case-study scenarios here studied. However, preliminary trials with different bioinformatic pipelines are suggested to evaluate their influence on population parameters according with the specific goals of each study.


Subject(s)
Metagenomics , Polymorphism, Single Nucleotide , Animals , Benchmarking , Genome , Sequence Analysis, DNA
5.
Genes (Basel) ; 11(1)2020 01 17.
Article in English | MEDLINE | ID: mdl-31963477

ABSTRACT

Rhamdia quelen, a Neotropical fish with hybridization between highly divergent mitochondrial DNA (mtDNA) lineages, represents an interesting evolutionary model. Previous studies suggested that there might be demographic differences between coastal lagoons and riverine environments, as well as divergent populations that could be reproductively isolated. Here, we investigated the genetic diversity pattern of this taxon in the Southern Neotropical Basin system that includes the La Plata Basin, Patos-Merin lagoon basin and the coastal lagoons draining to the SW Atlantic Ocean, through a population genomics approach using 2b-RAD-sequencing-derived single nucleotide polymorphisms (SNPs). The genomic scan identified selection footprints associated with divergence and suggested local adaptation environmental drivers. Two major genomic clusters latitudinally distributed in the Northern and Southern basins were identified, along with consistent signatures of divergent selection between them. Population structure based on the whole set of loci and on the presumptive neutral vs. adaptive loci showed deep genomic divergence between the two major clusters. Annotation of the most consistent SNPs under divergent selection revealed some interesting candidate genes for further functional studies. Moreover, signals of adaptation to a coastal lagoon environment mediated by purifying selection were found. These new insights provide a better understanding of the complex evolutionary history of R. quelen in the southernmost basin of the Neotropical region.


Subject(s)
Adaptation, Physiological/genetics , Catfishes/genetics , Evolution, Molecular , Genetic Loci , Polymorphism, Single Nucleotide , Animals , Genetics, Population , Genomics , Selection, Genetic
6.
Genes (Basel) ; 10(10)2019 10 11.
Article in English | MEDLINE | ID: mdl-31614537

ABSTRACT

The genus Austrolebias (Cyprinodontiformes: Rivulidae) represents a specious group of taxa following annual life cycles in the neotropical ichthyofauna. They live in temporary ponds and each generation must be completed in a few months, depending on environmental stochasticity. Annual fish survive the dry season through diapausing eggs buried in the substrate of these ponds. A hypothesized bimodal hybrid zone between two taxa of the genus, A. charrua and A. reicherti from Dos Patos Merin lagoon system, was recently proposed based on genetics and morphological analyses. However, hundreds of additional nuclear molecular markers should be used to strongly support this hypothesized bimodal pattern. In the present paper, we conducted RNA-seq-based sequencing of the transcriptomes from pools of individuals of A. charrua, A. reicherti and their putative natural hybrids from the previously characterized hybrid zone. As a result, we identified a set of 111,725 SNP (single nucleotide polymorphism) markers, representing presumably fixed allelic differences among the two species. The present study provided the first panel of 106 SNP markers as a single diagnostic multiplex assay and validated their capacity to reconstruct the patterns of the hybrid zone between both taxa. These nuclear markers combined with Cytb gene and morphological analyses detected a population structure in which some groups among the hybrid swarms showed different level of introgression towards one or the other parental species according to their geographic distribution. High-quality transcriptomes and a large set of gene-linked SNPs should greatly facilitate functional and population genomics studies in the hybrid zone of these endangered species.


Subject(s)
Cyprinodontiformes/classification , Cyprinodontiformes/genetics , Animals , Polymorphism, Single Nucleotide/genetics , Transcriptome/genetics , Exome Sequencing/methods
7.
Diagnóstico (Perú) ; 55(1): 38-41, ene.-mar. 2016. ilus
Article in Spanish | LILACS, LIPECS | ID: lil-788700

ABSTRACT

Se trata de un paciente joven que presenta trastorno del sensorio, alza térmica, lesiones petequiales y necróticas en piel, con plaquetopenia y leucocitosis que desarrolla una hemorragia intracerebral y luego distress respiratorio, es intubado, recibe antibioticoterapia y corticoides, es operado y mejora lentamente.


It is a patient with sensory impairment, high temperature, with petechial and necrotic lesions in skin, with disminish of platelets and increase of white blood cells, that developed an intracerebral hemorrhage, after a respiratory distress, was intubated and receive steroids and antibiotics, after was operated and improved slowly.


Subject(s)
Humans , Male , Adolescent , Cerebral Hemorrhage , Sepsis , Thrombocytopenia
8.
PLoS One ; 9(8): e104659, 2014.
Article in English | MEDLINE | ID: mdl-25126842

ABSTRACT

The present paper integrates phylogenetic and population genetics analyses based on mitochondrial and nuclear molecular markers in silversides, genus Odontesthes, from a non-sampled area in the SW Atlantic Ocean to address species discrimination and to define Managements Units for sustainable conservation. All phylogenetic analyses based on the COI mitochondrial gene were consistent to support the monophyly of the genus Odontesthes and to include O. argentinensis, O. perugiae-humensis and some O. bonariensis haplotypes in a basal polytomy conforming a major derivative clade. Microsatellites data revealed somewhat higher genetic variability values in the O. argentinensis-perugia populations than in O. bonariensis and O. perugia-humensis taxa. Contrasting population genetics structuring emerged from mitochondrial and microsatellites analyses in these taxa. Whereas mitochondrial data supported two major groups (O. argentinensis-perugia-humensis vs. O. bonariensis-perugiae-humensis populations), microsatellite data detected three major genetic entities represented by O. bonariensis, O. perugiae-humensis and an admixture of populations belonging to O. argentinensis-perugiae respectively. Therefore, the star COI polytomy in the tree topology involving these taxa could be interpreted by several hypothetic scenarios such as the existence of shared ancestral polymorphisms, incomplete lineage sorting in a radiating speciation process and/or reticulation events. Present findings support that promiscuous and recent contact between incipient species sharing asymmetric gene flow exchanges, blurs taxa boundaries yielding complicated taxonomy and Management Units delimitation in silverside genus Odontesthes from SW Atlantic Ocean basins.


Subject(s)
DNA, Mitochondrial/genetics , Fishes/classification , Gene Flow/genetics , Microsatellite Repeats/genetics , Mitochondria/genetics , Animals , Atlantic Ocean , Base Sequence , Evolution, Molecular , Fishes/genetics , Genetic Variation , Genetics, Population , Haplotypes/genetics , Phylogeny , Phylogeography , Sequence Analysis, DNA
9.
Finlay revista enf crón ; 3(1)2013. ilus, tab
Article in Spanish | CUMED | ID: cum-54922

ABSTRACT

Los cavernomas son tumores vasculares benignos con morfología similar a una frambuesa, comúnmente descritas dentro de las llamadas malformaciones crípticas vasculares, patologías neurológicas poco frecuentes. Constituyen un capítulo polémico dentro de las neurociencias, debido a la variabilidad clínico-topográfica de su presentación y su manejo continúa siendo controversial. Se presentan cuatro pacientes con cavernomas del neuroeje y su caracterización desde el punto vista clínico e imagenológico, hasta su desenlace final. La detección precoz, la comprensión, y el mejor manejo de los cavernomas del neuroeje son fruto del avance tecnológico contemporáneo. La revisión histórica del tema muestra la diferencia entre los pocos casos que se lograban diagnosticar clínicamente y/o por radiología convencional, y el mayor número de lesiones que se detectaban en autopsias o durante la cirugía(AU)


Cavernous malformations are benign vascular tumors, with a raspberry-like morphology, commonly described as part of the group of the so called cryptic vascular malformations, which are rare neurological presentations. They are considered to be a controversial chapter in neuroscience due to the clinical-topographic variability of their presentation. Their management remains controversial. We present the cases of four patients with neuraxis cavernomas who are characterization from clinical and imaging standpoint, up to their final outcome. Early detection, understanding, and better management of the neuraxis cavernous malformations are the result of contemporary technological advances. The historical review on the subject shows the difference between the few cases that could be clinically diagnosed through conventional radiology and the largest number of lesions detected at autopsy or during surgery(AU)


Subject(s)
Humans , Hemangioma, Cavernous, Central Nervous System/diagnosis , Hemangioma, Cavernous, Central Nervous System/physiopathology , Hemangioma, Cavernous, Central Nervous System/therapy , Early Diagnosis
10.
Article in Spanish | CUMED | ID: cum-49702

ABSTRACT

Paciente de 65 años, con antecedentes de hipertensión arterial y cardiopatía isquémica, que asistió a consulta en el departamento de Neurooftalmología, con protrusión del globo ocular izquierdo de aproximadamente 1 año de evolución, no dolorosa, además cierta disminución de la agudeza visual en dicho ojo. El fondo de ojo arrojó una discreta elevación del sector nasal inferior del disco en OI. Se realizó tomografía axial computarizada de órbita y resonancia magnética nuclear de órbitas. En ambas se apreció lesión en porción media superior de órbita izquierda, que comprimía el músculo recto superior. Se realizó cirugía orbitaria para extraer la lesión y se concluyó el diagnóstico histológico como un hemangioma cavernoso orbitario(AU)


A patient aged 65, with a history of hypertension and ischemic heart disease, who attended the consultation in the Department of Neuro-Ophthalmology with a non painful protrusion of left eyeball presenting about 1 year of evolution and certain decrease in the eyes visual acuity. Fundus of the eyes examination showed a slightly elevated inferior nasal sector of the disk in the left orbit. We performed computed tomography and magnetic resonance of the orbits. In both tests, an injury was detected in the upper middle portion of the left orbit compressing the superior rectus muscle. Orbital surgery was performed to remove the tumor. Histological diagnosis was concluded as an orbital cavernous hemangioma(AU)


Subject(s)
Humans , Male , Aged , Hemangioma, Cavernous/complications , Hemangioma, Cavernous/surgery , Hemangioma, Cavernous , Eye Neoplasms/complications , Eye Neoplasms/diagnosis , Eye Neoplasms/surgery , Exophthalmos/surgery , Exophthalmos/etiology
11.
CES odontol ; 16(2): 37-41, jul.-dic. 2003. graf
Article in Spanish | LILACS | ID: lil-468488

ABSTRACT

El propósito de estudio fue determinar el perfil psicológico de los pacientes con Síndrome de Disfunción Doloroso Temporomandibular (SDDTM), por medio de diferentes test psicológicos: Inventario de Ansiedad de Beck, Cuestionario de Personalidad EPQR-Abreviado. Cuestionario de depresión CD, Inventario de Hostilidad-IRA e Inventario de Estrés Diario. Se incluyeron 20 sujetos con diagnostico de SDDTM, con normo oclusión y sin desarreglo interno y se comparan con un grupo control de 20 pacientes sin diagnostico de SDDTM. Se encontraron diferencias significativas entre las escalas de ansiedad y los patrones de personalidad; no se encontraron diferencias significativas en las variables de ira, depresión y estrés diario, pero se observó una tendencia de los niveles de las variables a ser mayor en le grupo experimental. Se concluye que el perfil psicológico de los pacientes con SDDTM incluye un grado alto de ansiedad, una baja autoestima, propensión a la depresión, irritabilidad, además nuestra dificultad en sus relaciones interpersonales, las cuales manejan conflictivamente, los pacientes mas mentiras por apariencia y manejan un grado de estrés mas alto, sin embargo estas características no llegan a ser patológicas como se encontró en diversas investigaciones...


Subject(s)
Dental Anxiety , Temporomandibular Joint Dysfunction Syndrome , Dentistry , Psychology
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