705 resultados para skeletal maps


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AIM/HYPOTHESIS: Endoplasmic reticulum (ER) stress, which is involved in the link between inflammation and insulin resistance, contributes to the development of type 2 diabetes mellitus. In this study, we assessed whether peroxisome proliferator-activated receptor (PPAR)β/δ prevented ER stress-associated inflammation and insulin resistance in skeletal muscle cells. METHODS: Studies were conducted in mouse C2C12 myotubes, in the human myogenic cell line LHCN-M2 and in skeletal muscle from wild-type and PPARβ/δ-deficient mice and mice exposed to a high-fat diet. RESULTS: The PPARβ/δ agonist GW501516 prevented lipid-induced ER stress in mouse and human myotubes and in skeletal muscle of mice fed a high-fat diet. PPARβ/δ activation also prevented thapsigargin- and tunicamycin-induced ER stress in human and murine skeletal muscle cells. In agreement with this, PPARβ/δ activation prevented ER stress-associated inflammation and insulin resistance, and glucose-intolerant PPARβ/δ-deficient mice showed increased phosphorylated levels of inositol-requiring 1 transmembrane kinase/endonuclease-1α in skeletal muscle. Our findings demonstrate that PPARβ/δ activation prevents ER stress through the activation of AMP-activated protein kinase (AMPK), and the subsequent inhibition of extracellular-signal-regulated kinase (ERK)1/2 due to the inhibitory crosstalk between AMPK and ERK1/2, since overexpression of a dominant negative AMPK construct (K45R) reversed the effects attained by PPARβ/δ activation. CONCLUSIONS/INTERPRETATION: Overall, these findings indicate that PPARβ/δ prevents ER stress, inflammation and insulin resistance in skeletal muscle cells by activating AMPK.

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L’objectiu d’aquest projecte és crear un sistema de seguiment d’una flota de vehicles amb GPS en temps real. A partir d’un mòdul de captació, el servidor recull la informació geogràfica dels vehicles i l’emmagatzema. I amb un mòdul de processament, es mostra i controla els vehicles, els punts d’interès i els polígons del sistema de Geofencing. En primer lloc, faig una introducció a l’estat de l’art dels sistemes de seguiment de vehicles. A continuació, analitzo els requeriments, especifico el comportament desitjat del sistema, explico el disseny i la implementació. Per últim, faig un seguit de proves per extreure’n les conclusions.

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RYR1 mutations are the most common cause of structural congenital myopathies and may exhibit both dominant and recessive inheritance. Histopathological findings are variable and include central cores, multi-minicores, type 1 predominance/ uniformity, fibre type disproportion, increased internal nucleation and fatty and connective tissue. Until recently, diagnostic RYR1 sequencing was limited to mutational hotspots due to the large size of the gene. Since the introduction of full RYR1 sequencing in 2007 we have detected pathogenic mutations in 77 families: 39 had dominant inheritance and 38 recessive inheritance. In some cases with presumably recessive inheritance, only one heterozygous mutation inherited from an asymptomatic parent was identified. Of 28 dominant mutations, 6 were novel; 37 of the 59 recessive mutations were also novel. Dominant mutations were more frequently in recognized hotspot regions, while recessive mutations were distributed throughout the coding sequence. Dominant mutations were predominantly missense, whereas recessive mutations included many nonsense and splice mutations expected to result in reduced RyR1 protein. There was wide clinical variability in patients with both dominant and recessive inheritance. As a group, those with dominant mutations were generally more mildly affected than those with recessive inheritance, who had earlier onset and were weaker with more functional limitations. Extraocular muscle involvement was almost exclusively observed in the recessive group. Bulbar involvement was also more prominent in this group, resulting in a larger number requiring gastrostomy insertion. In conclusion, genomic sequencing of the entire RYR1 leads to the detection of many novel mutations, but may miss large genetic rearrangements in some cases. Assigning pathogenicity to novel mutations is often difficult and interpretation of genetic results in the context of clinical, histological and, increasingly, muscle MRI findings is essential.

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The aim of this paper is to analyse the colocation patterns of industries and firms. We study the spatial distribution of firms from different industries at a microgeographic level and from this identify the main reasons for this locational behaviour. The empirical application uses data from Mercantile Registers of Spanish firms (manufacturers and services). Inter-sectorial linkages are shown using self-organizing maps. Key words: clusters, microgeographic data, self-organizing maps, firm location JEL classification: R10, R12, R34

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The peroxisome proliferator-activated receptors (PPARs) are involved in the regulation of most of the pathways linked to lipid metabolism. PPARalpha and PPARbeta isotypes are known to regulate muscle fatty acid oxidation and a reciprocal compensation of their function has been proposed. Herein, we investigated muscle contractile and metabolic phenotypes in PPARalpha-/-, PPARbeta-/-, and double PPARalpha-/- beta-/- mice. Heart and soleus muscle analyses show that the deletion of PPARalpha induces a decrease of the HAD activity (beta-oxidation) while soleus contractile phenotype remains unchanged. A PPARbeta deletion alone has no effect. However, these mild phenotypes are not due to a reciprocal compensation of PPARbeta and PPARalpha functions since double gene deletion PPARalpha-PPARbeta mostly reproduces the null PPARalpha-mediated reduced beta-oxidation, in addition to a shift from fast to slow fibers. In conclusion, PPARbeta is not required for maintaining skeletal muscle metabolic activity and does not compensate the lack of PPARalpha in PPARalpha null mice.

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In legal medicine, the post mortem interval (PMI) of interest covers the last 50 years. When only human skeletal remains are found, determining the PMI currently relies mostly on the experience of the forensic anthropologist, with few techniques available to help. Recently, several radiometric methods have been proposed to reveal PMI. For instance, (14)C and (90)Sr bomb pulse dating covers the last 60 years and give reliable PMI when teeth or bones are available. (232)Th series dating has also been proposed but requires a large amount of bones. In addition, (210)Pb dating is promising but is submitted to diagenesis and individual habits like smoking that must be handled carefully. Here we determine PMI on 29 cases of forensic interest using (90)Sr bomb pulse. In 12 cases, (210)Pb dating was added to narrow the PMI interval. In addition, anthropological investigations were carried out on 15 cases to confront anthropological expertise to the radiometric method. Results show that 10 of the 29 cases can be discarded as having no forensic interest (PMI>50 years) based only on the (90)Sr bomb pulse dating. For 10 other cases, the additional (210)Pb dating restricts the PMI uncertainty to a few years. In 15 cases, anthropological investigations corroborate the radiometric PMI. This study also shows that diagenesis and inter-individual difference in radionuclide uptake represent the main sources of uncertainty in the PMI determination using radiometric methods.

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Cataracts are the leading cause of blindness in most countries. Although most hereditary cases appear to follow an autosomal dominant pattern of inheritance, autosomal recessive inheritance has been clearly documented and is probably underrecognized. We studied a large family-from a relatively isolated geographic region-whose members were affected by autosomal recessive adult-onset pulverulent cataracts. We mapped the disease locus to a 14-cM interval at a novel disease locus, 9q13-q22 (between markers D9S1123 and D9S257), with a LOD score of 4.7. The study of this progressive and age-related cataract phenotype may provide insight into the cause of the more common sporadic form of age-related cataracts.

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Dans le contexte climatique actuel, les régions méditerranéennes connaissent une intensification des phénomènes hydrométéorologiques extrêmes. Au Maroc, le risque lié aux inondations est devenu problématique, les communautés étant vulnérables aux événements extrêmes. En effet, le développement économique et urbain rapide et mal maîtrisé augmente l'exposition aux phénomènes extrêmes. La Direction du Développement et de la Coopération suisse (DDC) s'implique activement dans la réduction des risques naturels au Maroc. La cartographie des dangers et son intégration dans l'aménagement du territoire représentent une méthode efficace afin de réduire la vulnérabilité spatiale. Ainsi, la DDC a mandaté ce projet d'adaptation de la méthode suisse de cartographie des dangers à un cas d'étude marocain (la ville de Beni Mellal, région de Tadla-Azilal, Maroc). La méthode suisse a été adaptée aux contraintes spécifiques du terrain (environnement semi-aride, morphologie de piémont) et au contexte de transfert de connaissances (caractéristiques socio-économiques et pratiques). Une carte des phénomènes d'inondations a été produite. Elle contient les témoins morphologiques et les éléments anthropiques pertinents pour le développement et l'aggravation des inondations. La modélisation de la relation pluie-débit pour des événements de référence, et le routage des hydrogrammes de crue ainsi obtenus ont permis d'estimer quantitativement l'aléa inondation. Des données obtenues sur le terrain (estimations de débit, extension de crues connues) ont permis de vérifier les résultats des modèles. Des cartes d'intensité et de probabilité ont été obtenues. Enfin, une carte indicative du danger d'inondation a été produite sur la base de la matrice suisse du danger qui croise l'intensité et la probabilité d'occurrence d'un événement pour obtenir des degrés de danger assignables au territoire étudié. En vue de l'implémentation des cartes de danger dans les documents de l'aménagement du territoire, nous nous intéressons au fonctionnement actuel de la gestion institutionnelle du risque à Beni Mellal, en étudiant le degré d'intégration de la gestion et la manière dont les connaissances sur les risques influencent le processus de gestion. L'analyse montre que la gestion est marquée par une logique de gestion hiérarchique et la priorité des mesures de protection par rapport aux mesures passives d'aménagement du territoire. Les connaissances sur le risque restent sectorielles, souvent déconnectées. L'innovation dans le domaine de la gestion du risque résulte de collaborations horizontales entre les acteurs ou avec des sources de connaissances externes (par exemple les universités). Des recommandations méthodologiques et institutionnelles issues de cette étude ont été adressées aux gestionnaires en vue de l'implémentation des cartes de danger. Plus que des outils de réduction du risque, les cartes de danger aident à transmettre des connaissances vers le public et contribuent ainsi à établir une culture du risque. - Severe rainfall events are thought to be occurring more frequently in semi-arid areas. In Morocco, flood hazard has become an important topic, notably as rapid economic development and high urbanization rates have increased the exposure of people and assets in hazard-prone areas. The Swiss Agency for Development and Cooperation (SADC) is active in natural hazard mitigation in Morocco. As hazard mapping for urban planning is thought to be a sound tool for vulnerability reduction, the SADC has financed a project aimed at adapting the Swiss approach for hazard assessment and mapping to the case of Morocco. In a knowledge transfer context, the Swiss method was adapted to the semi-arid environment, the specific piedmont morphology and to socio-economic constraints particular to the study site. Following the Swiss guidelines, a hydro-geomorphological map was established, containing all geomorphic elements related to known past floods. Next, rainfall / runoff modeling for reference events and hydraulic routing of the obtained hydrographs were carried out in order to assess hazard quantitatively. Field-collected discharge estimations and flood extent for known floods were used to verify the model results. Flood hazard intensity and probability maps were obtained. Finally, an indicative danger map as defined within the Swiss hazard assessment terminology was calculated using the Swiss hazard matrix that convolves flood intensity with its recurrence probability in order to assign flood danger degrees to the concerned territory. Danger maps become effective, as risk mitigation tools, when implemented in urban planning. We focus on how local authorities are involved in the risk management process and how knowledge about risk impacts the management. An institutional vulnerability "map" was established based on individual interviews held with the main institutional actors in flood management. Results show that flood hazard management is defined by uneven actions and relationships, it is based on top-down decision-making patterns, and focus is maintained on active mitigation measures. The institutional actors embody sectorial, often disconnected risk knowledge pools, whose relationships are dictated by the institutional hierarchy. Results show that innovation in the risk management process emerges when actors collaborate despite the established hierarchy or when they open to outer knowledge pools (e.g. the academia). Several methodological and institutional recommendations were addressed to risk management stakeholders in view of potential map implementation to planning. Hazard assessment and mapping is essential to an integrated risk management approach: more than a mitigation tool, danger maps represent tools that allow communicating on hazards and establishing a risk culture.

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Intense inflammatory lesions and early development of interstitial fibrosis of the myocardium and skeletal muscle with spontaneous regression, have been described in Calomys callosus infected with Trypanosoma cruzi. The genetic types of collagen present in this model were investigated through immunohistochemistry using specific antibodies, combined with histopathology and Picro-Sirius staining of collagen. Thirty-five calomys were infected with the Colombian strain of T. cruzi and sacrificed at 24, 30, 40, 60 and 90 days post-infection. Inflammatory lesions and fibrogenesis were prominent at the early phase of infection and significantly decreased during late infection. Immunoisotyping of the matrix components was performed by indirect immunofluorescence on 5 µm thick cryostat sections using specific antibodies against laminin, fibronectin and isotypes I, III and IV of collagen. In the early phase, positive deposits of all the matrix components were present, with predominance of fibronectin, laminin and collagens types I and III in the myocardium and of types III and IV in the skeletal muscles. From the 40th day, type IV collagen predominates in the heart. At the late phase of infection (60th to 90th day), a clear fragmentation and decrease of all the matrix components were detected. Findings of the present study indicate that a modulation of the inflammatory process occurs in the model of C. callosus, leading to spontaneous regression of fibrosis independent of the genetic types of collagen involved in this process.

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AIMS: A high-fructose diet (HFrD) may play a role in the obesity and metabolic disorders epidemic. In rodents, HFrD leads to insulin resistance and ectopic lipid deposition. In healthy humans, a four-week HFrD alters lipid homoeostasis, but does not affect insulin sensitivity or intramyocellular lipids (IMCL). The aim of this study was to investigate whether fructose may induce early molecular changes in skeletal muscle prior to the development of whole-body insulin resistance. METHODS: Muscle biopsies were taken from five healthy men who had participated in a previous four-week HFrD study, during which insulin sensitivity (hyperinsulinaemic euglycaemic clamp), and intrahepatocellular lipids and IMCL were assessed before and after HFrD. The mRNA concentrations of 16 genes involved in lipid and carbohydrate metabolism were quantified before and after HFrD by real-time quantitative PCR. RESULTS: HFrD significantly (P<0.05) increased stearoyl-CoA desaturase-1 (SCD-1) (+50%). Glucose transporter-4 (GLUT-4) decreased by 27% and acetyl-CoA carboxylase-2 decreased by 48%. A trend toward decreased peroxisomal proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) was observed (-26%, P=0.06). All other genes showed no significant changes. CONCLUSION: HFrD led to alterations of SCD-1, GLUT-4 and PGC-1alpha, which may be early markers of insulin resistance.

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CONTEXT: Sarcopenia is thought to be associated with mitochondrial (Mito) loss. It is unclear whether the decrease in Mito content is consequent to aging per se or to decreased physical activity. OBJECTIVES: The objective of the study was to examine the influence of fitness on Mito content and function and to assess whether exercise could improve Mito function in older adults. DESIGN AND SUBJECTS: Three distinct studies were conducted: 1) a cross-sectional observation comparing Mito content and fitness in a large heterogeneous cohort of older adults; 2) a case-control study comparing chronically endurance-trained older adults and sedentary (S) subjects matched for age and gender; and 3) a 4-month exercise intervention in S. SETTING: The study was conducted at a university-based clinical research center. OUTCOMES: Mito volume density (MitoVd) was assessed by electron microscopy from vastus lateralis biopsies, electron transport chain proteins by Western blotting, mRNAs for transcription factors involved in M biogenesis by quantitative RT-PCR, and in vivo oxidative capacity (ATPmax) by (31)P-magnetice resonance spectroscopy. Peak oxygen uptake was measured by graded exercise test. RESULTS: Peak oxygen uptake was strongly correlated with MitoVd in 80 60- to 80-year-old adults. Comparison of chronically endurance-trained older adults vs S revealed differences in MitoVd, ATPmax, and some electron transport chain protein complexes. Finally, exercise intervention confirmed that S subjects are able to recover MitoVd, ATPmax, and specific transcription factors. CONCLUSIONS: These data suggest the following: 1) aging per se is not the primary culprit leading to Mito dysfunction; 2) an aerobic exercise program, even at an older age, can ameliorate the loss in skeletal muscle Mito content and may prevent aging muscle comorbidities; and 3) the improvement of Mito function is all about content.

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Estudi teòric sobre els Sistemes d'Informació Geogràfica (GIS) i sobre les especificacions que està publicant el Open Geospatial Consortium (OGC) com estàndards oberts que permetin les comunicacions entre distints GIS.

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Amb l'evolució de les noves tecnologies, els Sistemes d'Informació Geogràfica (SIG) es basen cada vegada menys en plataformes propietàries (únicament a l'abast de grans companyies). L'objectiu que persegueix el Open Geospatial Consortium (OGC) és que tot el món pugui beneficiar-se de la informació geogràfica, fent que els serveis estiguin disponibles en qualsevol xarxa, aplicació o sistema.

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Calomys callosus, a sylvatic reservoir of Trypanosoma cruzi, when infected with the Colombian strain (Biodeme Type III, T. cruzi I ) develops necrotic-inflammatory lesions and intense early fibrogenesis in the heart and skeletal muscles, that spontaneously regress. Participation of pro-inflammatory and pro-fibrogenic cytokines, such as tumor necrosis factor-alpha (TNF-alpha), gamma interferon (IFN-gamma) , and tumor growth factor-beta (TGF-beta), in the pathogenesis of the lesions is herein studied. Eighty C. callosus weighing 20 to 30 g were used. Seventy of them were inoculated with the Colombian strain (10(5) blood forms) and 10 were maintained as intact non-infected controls. After infection, C. callosus were sacrificed at different time-points from 15 to 70 days. The heart and skeletal muscle were processed for histopathology and cryopreserved for immunohistochemistry. Early necrotic lesions of parasitized skeletal muscle and myocardium with intense inflammatory lesions were present. Search for the in situ presence of TNF-alpha and IFN-gamma, was performed using rat-IgG anti-mouse antibodies against these cytokines. For the in situ search of TGF-beta, rabbit IgG anti-mouse antibodies were used. Immunolabeling of the cytokines in tissues of infected C. callosus was successful. The cytokines TNF-alpha, IFN-gamma , and TGF-beta were detected in the cytoplasm of macrophages and in the necrotic material from 15 to 45 days post-infection, decreasing their intensity until complete disappearance by the 65th day, which correlated with subsiding histopathological lesions. These findings suggest the participation of these cytokines in the control of parasite multiplication, in the development of an early fibrogenesis and in the regression of fibrotic-inflammatory lesions observed in C. callosus.