737 research outputs found
A simple method to estimate the significance level of the catch probability in the catch removal method in riverf ish populations
This work presents a method for estimating the signi®cance level of the capture probability when the capture removal
method is used in riverine ®sh populations. The method is based on adjustment of the linear relationship between capture
probability and an index of capture ef®cacy. With this method the population size, the statistic 2 and the signi®cance level of
the capture probability can be estimated. This is a simple technique which can be applied in the ®eld at the time of sampling. It
does not require the use of computers and can determine in situ whether the catch is valid to calculate the population density
A contribution to attenuation of health problems in Bolivia : bioactive natural compounds from native plants reported in traditional medicine
MicroRNA Profiling and Bioinformatics Target Analysis in Dorsal Hippocampus of Chronically Stressed Rats: Relevance to Depression Pathophysiology
Indexación: Scopus.1Laboratory of Neuroplasticity and Neurogenetics, Faculty of Chemical and Pharmaceutical Sciences, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago, Chile, 2National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Durham, NC, United States, 3Centro de Genómica y Bioinformática, Facultad de Ciencias, Universidad Mayor, Santiago, Chile, 4Millennium Institute for Integrative Biology (iBio), FONDAP Center for Genome Regulation, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Santiago, Chile, 5Department of Kinesiology, Faculty of Health Sciences, Universidad Católica del Maule, Talca, Chile, 6Escuela de Química y Farmacia, Facultad de Medicina, Universidad Andres Bello, Santiago, Chile.This study was supported by the following grants: FONDECYT 1120528 (JLF), Fondo Central de Investigación, Universidad de Chile ENL025/16 (JLF), ES090079 (JAC). Research in RG and EV laboratories is funded by Instituto Milenio iBio – Iniciativa Científica Milenio MINECON.Studies conducted in rodents subjected to chronic stress and some observations in humans after psychosocial stress, have allowed to establish a link between stress and the susceptibility to many complex diseases, including mood disorders. The studies in rodents have revealed that chronic exposure to stress negatively affects synaptic plasticity by triggering changes in the production of trophic factors, subunit levels of glutamate ionotropic receptors, neuron morphology, and neurogenesis in the adult hippocampus. These modifications may account for the impairment in learning and memory processes observed in chronically stressed animals. It is plausible then, that stress modifies the interplay between signal transduction cascades and gene expression regulation in the hippocampus, therefore leading to altered neuroplasticity and functioning of neural circuits. Considering that miRNAs play an important role in post-transcriptional-regulation of gene expression and participate in several hippocampus-dependent functions; we evaluated the consequences of chronic stress on the expression of miRNAs in dorsal (anterior) portion of the hippocampus, which participates in memory formation in rodents. Here, we show that male rats exposed to daily restraint stress (2.5 h/day) during 7 and 14 days display a differential profile of miRNA levels in dorsal hippocampus and remarkably, we found that some of these miRNAs belong to the miR-379-410 cluster. We confirmed a rise in miR-92a and miR-485 levels after 14 days of stress by qPCR, an effect that was not mimicked by chronic administration of corticosterone (14 days). Our in silico study identified the top-10 biological functions influenced by miR-92a, nine of which were shared with miR-485: Nervous system development and function, Tissue development, Behavior, Embryonic development, Organ development, Organismal development, Organismal survival, Tissue morphology, and Organ morphology. Furthermore, our in silico study provided a landscape of potential miRNA-92a and miR-485 targets, along with relevant canonical pathways related to axonal guidance signaling and cAMP signaling, which may influence the functioning of several neuroplastic substrates in dorsal hippocampus. Additionally, the combined effect of miR-92a and miR-485 on transcription factors, along with histone-modifying enzymes, may have a functional relevance by producing changes in gene regulatory networks that modify the neuroplastic capacity of the adult dorsal hippocampus under stress. © 2018 Muñoz-Llanos, García-Pérez, Xu, Tejos-Bravo, Vidal, Moyano, Gutiérrez, Aguayo, Pacheco, García-Rojo, Aliaga, Rojas, Cidlowski and Fiedler.https://www.frontiersin.org/articles/10.3389/fnmol.2018.00251/ful
Necrosis aséptica de astrágalo: presentación de un caso en la infancia
Se presenta un caso de necrosis aséptica de astrágalo en la infancia de origen
idiopático que, hasta donde sabemos, resulta único en la literatura mundial. Se trata
de una niña con un síndrome de Klippel-Trenaunay que debuta a la edad de 8 años con
un cuadro de dolor e inflamación intermitente en tobillo derecho. Se realiza estudio mediante
radiografías simples, RNM y gammagrafía con "Tc, llegando al diagnóstico de necrosis
avascular de astrágalo. Se trata mediante descarga del miembro durante 3 meses,
realizando la paciente vida normal con mínimas molestias a los 3 años del diagnósticoWe present one case of idiopathic avascular necrosis of the talus in a child.To our knowledge, this is the first case reported in the literature. The patient is a girl diagnosed of Klippel-Trenaunay syndrome of the ipsilateral limb. When she was 8 years old began with pain and swelling in the right ankle. Simple X-ray, isotopic bone scan and MRI were done, and she was diagnosed of avascular necrosis of the talar dome. The treatment was no weight bearing for three months. She has no sympthoms three years after diagnosis
Deleterious effects of litter on marine life
In this review we report new findings concerning interaction between marine debris and wildlife. Deleterious effects and consequences of entanglement, consumption and smothering are highlighted and discussed. The number of species known to have been affected by either entanglement or ingestion of plastic debris has doubled since 1997, from 267 to 557 species among all groups of wildlife. For marine turtles the number of affected species increased from 86 to 100 % (now 7 of 7 species), for marine mammals from 43 to 66 % (now 81 of 123 species) and for seabirds from 44 to 50 % of species (now 203 of 406 species). Strong increases in records were also listed for fish and invertebrates, groups that were previously not considered in detail. In future records of interactions between marine debris and wildlife we recommend to focus on standardized data on frequency of occurrence and quantities of debris ingested. In combination with dedicated impact studies in the wild or experiments, this will allow more detailed assessments of the deleterious effects of marine debris on individuals and populations
Some histopathological and clinical correlations in oral squamous cell carcinoma
Oral squamous cell carcinoma (SCC) is an important health problem that causes high mortality and morbidity. Correlations between some clinical and histopathological parameters were studied in 37 oral SCC. Some interesting aspects in oral SCC arising from precancerous lesions were found such as smaller size and a lower TNM stage at the moment of diagnosis. Histological and clinical differences were also found between tumors invading deep tissues by little groups of dissociated malignant cells and those invading by big masses of malignant cells. The possible significance of the intensity of peritumoral eosinophilic infiltrate was also studied.Le carcinome squameux de la cavité orale constitue un problème important de santé, qui est responsable d’une mortalité et d’une morbidité élevées. Nous avons étudié 37 carcinomes squameux de la cavité orale à travers un suivi clinique et une étude des corrélations entre les variables cliniques et histopathologiques. Nous avons relevé différents aspects intéressants en ce qui concerne les carcinomes squameux de la cavité orale qui procédaient de lésions précancéreuses comme leur petite dimention et le bas stade TNM au moment du diagnostic. Nous avons également trouvé des différences cliniques et histopathologiques entre les tumeurs qui envahissent les tissus adjecents en petits groupes et ceux qui le font en grandes masses de cellules malignes. Finalement, nous avons étudié la signification possible de l’intensité de l’infiltrat à eosinophiles peritumoral
Fulmar Litter EcoQO monitoring in the Netherlands - Update 2012 and 2013
Fulmars are purely offshore foragers that ingest all sorts of litter from the sea surface and do not regurgitate poorly degradable diet components like plastics. Initial size of ingested debris is usually in the range of millimetres to centimeters, but may be considerably larger for flexible items as for instance threadlike or sheetlike materials. Items must gradually wear down in the muscular stomach to a size small enough for passage to the intestines. During this process, plastics accumulate in the stomach to a level that integrates litter levels encountered in their foraging area for a period of probably up to a few weeks. The Dutch monitoring approach using beached fulmars was developed for international implementation by OSPAR
Transmission properties of a single metallic slit: From the subwavelength regime to the geometrical-optics limit
In this work we explore the transmission properties of a single slit in a
metallic screen. We analyze the dependence of these properties on both slit
width and angle of incident radiation. We study in detail the crossover between
the subwavelength regime and the geometrical-optics limit. In the subwavelength
regime, resonant transmission linked to the excitation of waveguide resonances
is analyzed. Linewidth of these resonances and their associated electric field
intensities are controlled by just the width of the slit. More complex
transmission spectra appear when the wavelength of light is comparable to the
slit width. Rapid oscillations associated to the emergence of different
propagating modes inside the slit are the main features appearing in this
regime.Comment: Accepted for publication in Phys. Rev.
Fracturas de estrés en la infancia
Aportamos 13 casos de fracturas de estrés diagnosticadas en nuestro centro en los
últimos 5 años ocurridas en niños entre 4 y 15 años de edad. Encontramos una mayor incidencia
en el sexo masculino (9 de los 13 casos), así como un claro predominio de la localización en el tercio
proximal de la diáfisis tibial (7 casos), hallazgos que concuerdan con los referidos en la literatura.
Uno de los aspectos más interesantes de este tipo de fracturas es su similitud tanto clínica
como radiológica con procesos de origen infeccioso y neoplásico, por lo que la realización de un
correcto diagnóstico diferencial, apoyado en las radiografías simples, tomografías, gammagrafía,
TAC y, más recientemente, RMN, resulta crucial.We present 13 cases of stress fractures in children, collected in our center during
the last 5 years. The age of patients ranged from 4 to 15 years old. In agreement with literature,
we found a greater incidence on males (9 of 13 cases), and a predominant location on the proximal
shaft of the tibia (7 cases). One of the most interesting aspects of this type of fractures is their
clinical and radiological similarity with infections and tumors. Therefore, it is essential to achieve
a right diagnosis based on standard radiographs, tomography, radionuclide bone scan, CT-scan
and, most recently, MRI
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