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1.
Diagnostics (Basel) ; 12(7)2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35885610

RESUMEN

BACKGROUND: Plantar fibromatosis, known as Ledderhose disease, is a neoplastic disease characterized by a locally-aggressive bland fibroblastic proliferation. Although Pacinian corpuscles alterations are commonly described in palmar fibromatosis, there are still no references about Pacinian corpuscles alterations in the rarer plantar version. METHODS: We present a case report where a wide cutaneous resection, including the plantar fascia was performed, allowing a detailed study of Pacinian corpuscles. Pacinian corpuscles were analyzed using immunohistochemistry for neurofilament proteins, S100 protein, CD34, vimentin, glucose transporter 1, epithelial membrane antigen, neural-cell adhesion molecule, actin, desmin, type IV collagen, and high-affinity neurotrophin Trk-receptors. Moreover, the density and the size of the corpuscles were determined. RESULTS: A clear increase in the number (hyperplasia) of Pacinian corpuscles was evidenced in the Ledderhose disease plantar fascia in comparison with similarly aged normal subjects. Pacinian hypertrophy was not demonstrated, but a significant decrease in the number of corpuscular lamellae was noted, with a subsequent increase in the interlamellar spaces. Pacinian corpuscles from the pathological plantar fascia showed an abnormal structure and immunohistochemical profile, generally without identifiable axons, and also absence of an inner core or an intermediate layer. Moreover, other molecules related with trophic maintenance of corpuscles were also absent. Finally, a vascular proliferation was commonly noted in some corpuscles, which involved all corpuscular constituents. CONCLUSION: The observed Pacinian corpuscles hyperplasia could be considered a diagnostic clue of plantar fibromatosis.

2.
Mol Ecol ; 30(23): 6162-6177, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34416064

RESUMEN

Runs of homozygosity (ROH) occur when offspring inherit haplotypes that are identical by descent from each parent. Length distributions of ROH are informative about population history; specifically, the probability of inbreeding mediated by mating system and/or population demography. Here, we investigated whether variation in killer whale (Orcinus orca) demographic history is reflected in genome-wide heterozygosity and ROH length distributions, using a global data set of 26 genomes representative of geographic and ecotypic variation in this species, and two F1 admixed individuals with Pacific-Atlantic parentage. We first reconstructed demographic history for each population as changes in effective population size through time using the pairwise sequential Markovian coalescent (PSMC) method. We found a subset of populations declined in effective population size during the Late Pleistocene, while others had more stable demography. Genomes inferred to have undergone ancestral declines in effective population size, were autozygous at hundreds of short ROH (<1 Mb), reflecting high background relatedness due to coalescence of haplotypes deep within the pedigree. In contrast, longer and therefore younger ROH (>1.5 Mb) were found in low latitude populations, and populations of known conservation concern. These include a Scottish killer whale, for which 37.8% of the autosomes were comprised of ROH >1.5 Mb in length. The fate of this population, in which only two adult males have been sighted in the past five years, and zero fecundity over the last two decades, may be inextricably linked to its demographic history and consequential inbreeding depression.


Asunto(s)
Orca , Animales , Genoma , Homocigoto , Endogamia , Masculino , Polimorfismo de Nucleótido Simple , Densidad de Población , Orca/genética
3.
Mol Ecol ; 28(14): 3427-3444, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31131963

RESUMEN

Reconstruction of the demographic and evolutionary history of populations assuming a consensus tree-like relationship can mask more complex scenarios, which are prevalent in nature. An emerging genomic toolset, which has been most comprehensively harnessed in the reconstruction of human evolutionary history, enables molecular ecologists to elucidate complex population histories. Killer whales have limited extrinsic barriers to dispersal and have radiated globally, and are therefore a good candidate model for the application of such tools. Here, we analyse a global data set of killer whale genomes in a rare attempt to elucidate global population structure in a nonhuman species. We identify a pattern of genetic homogenisation at lower latitudes and the greatest differentiation at high latitudes, even between currently sympatric lineages. The processes underlying the major axis of structure include high drift at the edge of species' range, likely associated with founder effects and allelic surfing during postglacial range expansion. Divergence between Antarctic and non-Antarctic lineages is further driven by ancestry segments with up to four-fold older coalescence time than the genome-wide average; relicts of a previous vicariance during an earlier glacial cycle. Our study further underpins that episodic gene flow is ubiquitous in natural populations, and can occur across great distances and after substantial periods of isolation between populations. Thus, understanding the evolutionary history of a species requires comprehensive geographic sampling and genome-wide data to sample the variation in ancestry within individuals.


Asunto(s)
Flujo Génico , Genoma , Orca/genética , Alelos , Animales , Regiones Antárticas , Secuencia de Bases , Núcleo Celular/genética , ADN Mitocondrial/genética , Flujo Genético , Variación Genética , Geografía , Cadenas de Markov , Modelos Genéticos , Filogenia , Análisis de Componente Principal
4.
PLoS One ; 12(9): e0184673, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28898268

RESUMEN

The ecological role of species can vary among populations depending on local and regional differences in diet. This is particularly true for top predators such as the bottlenose dolphin (Tursiops truncatus), which exhibits a highly varied diet throughout its distribution range. Local dietary assessments are therefore critical to fully understand the role of this species within marine ecosystems, as well as its interaction with important ecosystem services such as fisheries. Here, we combined stomach content analyses (SCA) and stable isotope analyses (SIA) to describe bottlenose dolphins diet in the Gulf of Cadiz (North Atlantic Ocean). Prey items identified using SCA included European conger (Conger conger) and European hake (Merluccius merluccius) as the most important ingested prey. However, mass-balance isotopic mixing model (MixSIAR), using δ13C and δ15N, indicated that the assimilated diet consisted mainly on Sparidae species (e.g. seabream, Diplodus annularis and D. bellottii, rubberlip grunt, Plectorhinchus mediterraneus, and common pandora, Pagellus erythrinus) and a mixture of other species including European hake, mackerels (Scomber colias, S. japonicus and S. scombrus), European conger, red bandfish (Cepola macrophthalma) and European pilchard (Sardina pilchardus). These contrasting results highlight differences in the temporal and taxonomic resolution of each approach, but also point to potential differences between ingested (SCA) and assimilated (SIA) diets. Both approaches provide different insights, e.g. determination of consumed fish biomass for the management of fish stocks (SCA) or identification of important assimilated prey species to the consumer (SIA).


Asunto(s)
Delfín Mular/fisiología , Dieta , Cadena Alimentaria , Animales , Conducta Alimentaria , Peces/clasificación , Análisis Espectral , Estómago/química
5.
Mar Pollut Bull ; 109(1): 512-520, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27210556

RESUMEN

A visual monitoring of marine mammals was carried out during a seismic acquisition survey performed in waters south of Portugal with the aim of assessing the likelihood of encountering Mysticeti species in this region as well as to determine the impact of the seismic activity upon encounter. Sightings and effort data were assembled with a range of environmental variables at different lags, and a Bayesian site-occupancy modeling approach was used to develop prediction maps and evaluate how species-specific habitat conditions evolved throughout the presence or not of seismic activity. No statistical evidence of a decrease in the sighting rates of Mysticeti by comparison to source activity was found. Indeed, it was found how Mysticeti distribution during the survey period was driven solely by environmental variables. Although further research is needed, possible explanations may include anthropogenic noise habituation and zone of seismic activity coincident with a naturally low density area.


Asunto(s)
Teorema de Bayes , Cetáceos , Animales , Ecosistema , Ruido , Portugal , Análisis Espacial
6.
Sci Rep ; 6: 18573, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26766430

RESUMEN

Organochlorine (OC) pesticides and the more persistent polychlorinated biphenyls (PCBs) have well-established dose-dependent toxicities to birds, fish and mammals in experimental studies, but the actual impact of OC pollutants on European marine top predators remains unknown. Here we show that several cetacean species have very high mean blubber PCB concentrations likely to cause population declines and suppress population recovery. In a large pan-European meta-analysis of stranded (n = 929) or biopsied (n = 152) cetaceans, three out of four species:- striped dolphins (SDs), bottlenose dolphins (BNDs) and killer whales (KWs) had mean PCB levels that markedly exceeded all known marine mammal PCB toxicity thresholds. Some locations (e.g. western Mediterranean Sea, south-west Iberian Peninsula) are global PCB "hotspots" for marine mammals. Blubber PCB concentrations initially declined following a mid-1980s EU ban, but have since stabilised in UK harbour porpoises and SDs in the western Mediterranean Sea. Some small or declining populations of BNDs and KWs in the NE Atlantic were associated with low recruitment, consistent with PCB-induced reproductive toxicity. Despite regulations and mitigation measures to reduce PCB pollution, their biomagnification in marine food webs continues to cause severe impacts among cetacean top predators in European seas.


Asunto(s)
Delfines , Bifenilos Policlorados/efectos adversos , Contaminantes del Agua/efectos adversos , Contaminación Química del Agua , Orca , Animales , Europa (Continente) , Femenino , Geografía , Masculino , Dinámica Poblacional , Análisis Espacio-Temporal
7.
Lima; s.n; 2014. 74 p. tab, graf.
Tesis en Español | LIPECS | ID: biblio-1113838

RESUMEN

Objetivo: Determinar el nivel de actividad física de los estudiantes de la Escuela de Tecnología Médica de la Facultad de Medicina de la Universidad Nacional Mayor de San Marcos, año 2013. Materiales y Métodos: Se realizó un estudio observacional, descriptivo, correlacional, de corte transversal. La muestra estuvo constituida por 259 estudiantes de la Escuela de Tecnología Médica de la Facultad de Medicina de la Universidad Nacional Mayor de San Marcos en el mes de Diciembre del 2013, obtenido por muestreo probabilístico aleatorio estratificado por asignación proporcional; teniendo en cuenta asimismo los criterios de inclusión y exclusión. El procedimiento consistió en aplicar el Cuestionario Global de Actividad Física (GPAQ). Para el análisis estadístico se empleó el software Microsoft Excel y IBM SPSS Statistics versión 19. Resultados: 55.2 por ciento de los estudiantes presenta Bajo nivel de actividad física. De las cuatro áreas académicas, Terapia Física y Rehabilitación y Terapia Ocupacional tienen mayor porcentaje de estudiantes con nivel elevado de actividad física respecto a las otras dos áreas (p=0,043). Los varones presentan mayor actividad física que las mujeres (p=0,014), Respecto a la conducta sedentaria, los estudiantes de Terapia Física y Rehabilitación pasan menos horas sentados por día y Radiología es el área con mayor conducta sedentaria. Concusiones: La mayoría de los estudiantes presenta Bajo nivel de actividad física, independientemente del área académica, año de estudios, edad y sexo.


Objective: To determine the level of physical activity of students of the School of Medical Technology, Faculty of Medicine National University of San Marcos, 2013. Materials and Methods: An observational descriptive, correlational, cross-sectional study. The sample consisted of 259 students from the School of Medical Technology, Faculty of Medicine National University of San Marcos in December, 2013, obtained by stratified random probability sampling, proportional allocation; also taking into account the criteria for inclusion and exclusion. The procedure consisted of applying the Global Physical Activity Questionnaire (GPAQ). For statistical analysis, Microsoft Excel and IBM SPSS software version 19 was used. Results: 55.2 per cent of students present low level of physical activity. Of the four academic areas, Physical Therapy and Rehabilitation and Occupational Therapy have a higher percentage of students with high level of physical activity compared to the other two areas (p=0.043). Males have greater physical activity than women (p=0.014). Regarding sedentary behavior, students of Physical Therapy and Rehabilitation spend fewer hours per day sitting and Radiology is the area most sedentary behavior. Conclusions: The majority of students, regardless of academic area, year of study, age and sex, perform low level of physical activity.


Asunto(s)
Masculino , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Actividad Motora , Estudiantes del Área de la Salud , Ejercicio Físico , Estudios Observacionales como Asunto , Estudios Transversales
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