999 resultados para animal anatomy
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BACKGROUND: Elucidating disease and developmental dysfunction requires understanding variation in phenotype. Single-species model organism anatomy ontologies (ssAOs) have been established to represent this variation. Multi-species anatomy ontologies (msAOs; vertebrate skeletal, vertebrate homologous, teleost, amphibian AOs) have been developed to represent 'natural' phenotypic variation across species. Our aim has been to integrate ssAOs and msAOs for various purposes, including establishing links between phenotypic variation and candidate genes. RESULTS: Previously, msAOs contained a mixture of unique and overlapping content. This hampered integration and coordination due to the need to maintain cross-references or inter-ontology equivalence axioms to the ssAOs, or to perform large-scale obsolescence and modular import. Here we present the unification of anatomy ontologies into Uberon, a single ontology resource that enables interoperability among disparate data and research groups. As a consequence, independent development of TAO, VSAO, AAO, and vHOG has been discontinued. CONCLUSIONS: The newly broadened Uberon ontology is a unified cross-taxon resource for metazoans (animals) that has been substantially expanded to include a broad diversity of vertebrate anatomical structures, permitting reasoning across anatomical variation in extinct and extant taxa. Uberon is a core resource that supports single- and cross-species queries for candidate genes using annotations for phenotypes from the systematics, biodiversity, medical, and model organism communities, while also providing entities for logical definitions in the Cell and Gene Ontologies. THE ONTOLOGY RELEASE FILES ASSOCIATED WITH THE ONTOLOGY MERGE DESCRIBED IN THIS MANUSCRIPT ARE AVAILABLE AT: http://purl.obolibrary.org/obo/uberon/releases/2013-02-21/ CURRENT ONTOLOGY RELEASE FILES ARE AVAILABLE ALWAYS AVAILABLE AT: http://purl.obolibrary.org/obo/uberon/releases/
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Resumo: O objetivo deste trabalho foi propor modelos que considerem estrutura irregular dos dados e avaliá-los em relação a modelos utilizados com tempos regulares. Foram considerados os modelos de crescimento Gompertz, Logístico e Von Bertalanffy com estruturas regular e irregular para os erros. A metodologia foi exemplificada com o uso de dados reais e simulados. Foram utilizados 16 pesos médios de 160 animais da raça Hereford, com pesagens do nascimento até aproximadamente 2 anos de idade. Para cada modelo, os parâmetros do melhor ajuste foram utilizados para simulação. O ajuste dos modelos melhora quando a estrutura original dos dados é levada em consideração, com redução na soma de quadrados dos resíduos e no valor do critério de Akaike.
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Converging evidence favors an abnormal susceptibility to oxidative stress in schizophrenia. Decreased levels of glutathione (GSH), the major cellular antioxidant and redox regulator, was observed in cerebrospinal-fluid and prefrontal cortex of patients. Importantly, abnormal GSH synthesis of genetic origin was observed: Two case-control studies showed an association with a GAG trinucleotide repeat (TNR) polymorphism in the GSH key synthesizing enzyme glutamate-cysteine-ligase (GCL) catalytic subunit (GCLC) gene. The most common TNR genotype 7/7 was more frequent in controls, whereas the rarest TNR genotype 8/8 was three times more frequent in patients. The disease associated genotypes (35% of patients) correlated with decreased GCLC protein, GCL activity and GSH content. Similar GSH system anomalies were observed in early psychosis patients. Such redox dysregulation combined with environmental stressors at specific developmental stages could underlie structural and functional connectivity anomalies. In pharmacological and knock-out (KO) models, GSH deficit induces anomalies analogous to those reported in patients. (a) morphology: spine density and GABA-parvalbumine immunoreactivity (PV-I) were decreased in anterior cingulate cortex. KO mice showed delayed cortical PV-I at PD10. This effect is exacerbated in mice with increased DA from PD5-10. KO mice exhibit cortical impairment in myelin and perineuronal net known to modulate PV connectivity. (b) physiology: In cultured neurons, NMDA response are depressed by D2 activation. In hippocampus, NMDA-dependent synaptic plasticity is impaired and kainate induced g-oscillations are reduced in parallel to PV-I. (c) cognition: low GSH models show increased sensitivity to stress, hyperactivity, abnormal object recognition, olfactory integration and social behavior. In a clinical study, GSH precursor N-acetyl cysteine (NAC) as add on therapy, improves the negative symptoms and decreases the side effects of antipsychotics. In an auditory oddball paradigm, NAC improves the mismatched negativity, an evoked potential related to pre-attention and to NMDA receptors function. In summary, clinical and experimental evidence converge to demonstrate that a genetically induced dysregulation of GSH synthesis combined with environmental insults in early development represent a major risk factor contributing to the development of schizophrenia
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Knowledge of the pathological diagnosis before deciding the best strategy for treating parasellar lesions is of prime importance, due to the relative high morbidity and side-effects of open direct approaches to this region, known to be rich in important vasculo-nervous structures. When imaging is not evocative enough to ascertain an accurate pathological diagnosis, a percutaneous biopsy through the transjugal-transoval route (of Hartel) may be performed to guide the therapeutic decision.The chapter is based on the authors' experience in 50 patients who underwent the procedure over the ten past years. There was no mortality and only little (mostly transient) morbidity. Pathological diagnosis accuracy of the method revealed good, with a sensitivity of 0.83 and a specificity of 1.In the chapter the authors first recall the surgical anatomy background from personal laboratory dissections. They then describe the technical procedure, as well as the tissue harvesting method. Finally they define indications together with the decision-making process.Due to the constraint trajectory of the biopsy needle inserted through the Foramen Ovale, accessible lesions are only those located in the Meckel trigeminal Cave, the posterior sector of the cavernous sinus compartment, and the upper part of the petroclival region.The authors advise to perform this percutaneous biopsy method when imaging does not provide sufficient evidence of the pathological nature of the lesion, for therapeutic decision. Goal is to avoid unnecessary open surgery or radiosurgery, also inappropriate chemo-/radio-therapy.
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This paper presents a general expression to predict breeding values using animal models when the base population is selected, i.e. the means and variances of breeding values in the base generation differ among individuals. Rules for forming the mixed model equations are also presented. A numerical example illustrates the procedure.
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Chemical reactions in living cells are under strict enzyme control and conform to a tightly regulated metabolic program. However, uncontrolled and potentially deleterious endogenous reactions occur, even under physiological conditions. Aging, in this chemical context, could be viewed as an entropic process, the result of chemical side reactions that chronically and cumulatively degrade the function of biological systems. Mitochondria are a main source of reactive oxygen species (ROS) and chemical sidereactions in healthy aerobic tissues and are the only known extranuclear cellular organelles in animal cells that contain their own DNA (mtDNA). ROS can modify mtDNA directly at the sugar-phosphate backbone or at the bases, producing many different oxidatively modified purines and pyrimidines, as well as single and double strand breaks and DNA mutations. In this scenario, natural selection tends to decrease the mitochondrial ROS generation, the oxidative damage to mtDNA, and the mitochondrial mutation rate in long-lived species, in agreement with the mitochondrial oxidative stress theory of aging.
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Aim of study: To identify species of wood samples based on common names and anatomical analyses of their transversal surfaces (without microscopic preparations). Area of study: Spain and South America Material and methods: The test was carried out on a batch of 15 lumber samples deposited in the Royal Botanical Garden in Madrid, from the expedition by Ruiz and Pavon (1777-1811). The first stage of the methodology is to search and to make a critical analysis of the databases which list common nomenclature along with scientific nomenclature. A geographic filter was then applied to the information resulting from the samples with a more restricted distribution. Finally an anatomical verification was carried out with a pocket microscope with a magnification of x40, equipped with a 50 micrometers resolution scale. Main results: The identification of the wood based exclusively on the common name is not useful due to the high number of alternative possibilities (14 for “naranjo”, 10 for “ébano”, etc.). The common name of one of the samples (“huachapelí mulato”) enabled the geographic origin of the samples to be accurately located to the shipyard area in Guayaquil (Ecuador). Given that Ruiz y Pavon did not travel to Ecuador, the specimens must have been obtained by Tafalla. It was possible to determine correctly 67% of the lumber samples from the batch. In 17% of the cases the methodology did not provide a reliable identification. Research highlights: It was possible to determine correctly 67% of the lumber samples from the batch and their geographic provenance. The identification of the wood based exclusively on the common name is not useful.
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Stockton 1789