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Francisco Eduardo Martin-Cano Mercedes Caso-Agundez Cristina Camello-Almaraz Francisco Juan Santos María Teresa Espin Juan Antonio Madrid Adolfo Diez-Perez Pedro Javier Camello Maria Jose Pozo 《Journal of physiology and biochemistry》2017,73(1):77-87
Urinary bladder function consists in the storage and controlled voiding of urine. Translational studies require animal models that match human characteristics, such as Octodon degus, a diurnal rodent. This study aims to characterize the contractility of the detrusor muscle and the morphology and code of the vesical plexus from O. degus. Body temperature was measured by an intra-abdominal sensor, the contractility of detrusor strips was evaluated by isometric tension recording, and the vesical plexus was studied by electrical field stimulation (EFS) and immunofluorescence. The animals showed a diurnal chronotype as judged from core temperature. The myogenic contractile response of the detrusor muscle to increasing doses of KCl reached its maximum (31.04 mN/mm2) at 60 mM. In the case of cumulative dose–response of bethanecol, the maximum response (37.42 mN/mm2) was reached at 3.2 × 10?4 M. The response to ATP was clearly smaller (3.8 mN/mm2). The pharmacological dissection of the EFS-induced contraction identified ACh and sensory fibers as the main contributors to this response. The neurons of the vesical plexus were located mainly in the trigone area, grouped in big and small ganglia. Out of them, 48.1 % of the neurons were nitrergic and 62.7 % cholinergic. Our results show functional and morphological similarities between the urinary bladder of O. degus and that of humans. 相似文献
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BackgroundHousehold contacts of active tuberculosis cases are at high risk of getting tuberculosis disease. Tuberculosis detection rate among contacts of household members is high. Hence, this study investigated household contact screening adherence and associated factors among tuberculosis patients in Amhara region, Ethiopia.MethodsA cross-sectional study was conducted from April 10 - June 30, 2013 in five urban districts of Amhara region, where 418 patients receiving treatment at tuberculosis clinic were interviewed. All patients were interviewed using structured and pre-tested questionnaire. Bringing at least one household contact to TB clinic was regarded as adherent to household contacts screening. Bivariate and multiple logistic regressions were used to investigate association.ResultsThe overall adherence to household contact screening in Amhara region was 33.7%. Adherence was higher among Muslims than Christians. Adherence was high if patient took health education from Health Care Worker [AOR: 3.22, 95% CI: 1.88 to 5.51] and 2.17 times higher if patient had sufficient knowledge on tuberculosis [AOR: 2.17, 95% CI: 1.29 to 3.67] during interview. Relationship with contact was a significant [AOR: 0.4, 95% CI: 0.2 to 0.9] social related factor.ConclusionOne third of tuberculosis patients adhered to household contact screening in health facilities during their treatment course. Promoting knowledge of tuberculosis in the community and continuous health education to tuberculosis patients are recommended. 相似文献
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V. Ordóñez M. Pascual M. Fernández-Tejedor M. C. Pineda D. Tagliapietra X. Turon 《Biological invasions》2015,17(7):2075-2085
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“Beyond GDP” initiatives flag the limits of the quantitative indicators of progress currently used for governance. Focusing on the quality assessment of quantitative information used for governance, we use some of the conceptual tools of theoretical ecology and evolutionary biology in order to identify the pre-analytical choices that determine the usefulness and pertinence of a model. Starting from the definition of a model as a formal representation of a specific and necessarily subjective observation, we show that the production of indicators is the final result of a series of decisions on what to observe and how. These choices, in turn, depend on the narrative, or set of narratives, adopted. Narratives provide causality and context to knowledge claims and are needed to select the indicators to be used for policy. Moving beyond the GDP debate requires reflexivity, that is, awareness of the key role that pre-analytical choices play in the definition of both the relevance of the chosen perceptions and narratives (determined by the normative stands of different actors – who defines wellbeing?), and the usefulness of the chosen models and data (determined by the pertinence of the resulting representation – how to measure wellbeing?). Reflexivity is essential in order to take into account the purposes for which different indicators were created and to define new purposes for the “beyond GDP” indicators. 相似文献
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Magdalena Guardiola María Jesús Uriz Pierre Taberlet Eric Coissac Owen Simon Wangensteen Xavier Turon 《PloS one》2015,10(10)
Marine sediments are home to one of the richest species pools on Earth, but logistics and a dearth of taxonomic work-force hinders the knowledge of their biodiversity. We characterized α- and β-diversity of deep-sea assemblages from submarine canyons in the western Mediterranean using an environmental DNA metabarcoding. We used a new primer set targeting a short eukaryotic 18S sequence (ca. 110 bp). We applied a protocol designed to obtain extractions enriched in extracellular DNA from replicated sediment corers. With this strategy we captured information from DNA (local or deposited from the water column) that persists adsorbed to inorganic particles and buffered short-term spatial and temporal heterogeneity. We analysed replicated samples from 20 localities including 2 deep-sea canyons, 1 shallower canal, and two open slopes (depth range 100–2,250 m). We identified 1,629 MOTUs, among which the dominant groups were Metazoa (with representatives of 19 phyla), Alveolata, Stramenopiles, and Rhizaria. There was a marked small-scale heterogeneity as shown by differences in replicates within corers and within localities. The spatial variability between canyons was significant, as was the depth component in one of the canyons where it was tested. Likewise, the composition of the first layer (1 cm) of sediment was significantly different from deeper layers. We found that qualitative (presence-absence) and quantitative (relative number of reads) data showed consistent trends of differentiation between samples and geographic areas. The subset of exclusively benthic MOTUs showed similar patterns of β-diversity and community structure as the whole dataset. Separate analyses of the main metazoan phyla (in number of MOTUs) showed some differences in distribution attributable to different lifestyles. Our results highlight the differentiation that can be found even between geographically close assemblages, and sets the ground for future monitoring and conservation efforts on these bottoms of ecological and economic importance. 相似文献
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Amit Gautam Richard J. Grainger J. Vilardell J. David Barrass Jean D. Beggs 《Nucleic acids research》2015,43(6):3309-3317
Pre-mRNA splicing involves two transesterification steps catalyzed by the spliceosome. How RNA substrates are positioned in each step and the molecular rearrangements involved, remain obscure. Here, we show that mutations in PRP16, PRP8, SNU114 and the U5 snRNA that affect this process interact genetically with CWC21, that encodes the yeast orthologue of the human SR protein, SRm300/SRRM2. Our microarray analysis shows changes in 3′ splice site selection at elevated temperature in a subset of introns in cwc21Δ cells. Considering all the available data, we propose a role for Cwc21p positioning the 3′ splice site at the transition to the second step conformation of the spliceosome, mediated through its interactions with the U5 snRNP. This suggests a mechanism whereby SRm300/SRRM2, might influence splice site selection in human cells. 相似文献
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