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51.

Objectives

Previous clinical audits of COPD have provided relevant information about medical intervention in exacerbation admissions. The present study aims to evaluate adherence to current guidelines in COPD through a clinical audit.

Methods

This is a pilot clinical audit performed in hospital outpatient respiratory clinics in Andalusia, Spain (eight provinces with more than 8 million inhabitants), including 9 centers (20% of the public centers in the area) between 2013 and 2014. Cases with an established diagnosis of COPD based on risk factors, clinical symptoms, and a post-bronchodilator FEV1/FVC ratio of less than 0.70 were deemed eligible. The performance of the outpatient clinics was benchmarked against three guidance documents available at the time of the audit. The appropriateness of the performance was categorized as excellent (>80%), good (60−80%), adequate (40−59%), inadequate (20−39%), and highly inadequate (<20%).

Results

During the audit, 621 clinical records were audited. Adherence to the different guidelines presented a considerable variability among the different participating hospitals, with an excellent or good adherence for symptom recording, MRC or CAT use, smoking status evaluation, spirometry, or bronchodilation therapy. The most outstanding areas for improvement were the use of the BODE index, the monitoring of treatments, the determination of alpha1-antitrypsin, the performance of exercise testing, and vaccination recommendations.

Conclusions

The present study reflects the situation of clinical care for COPD patients in specialized secondary care outpatient clinics. Adherence to clinical guidelines shows considerable variability in outpatient clinics managing COPD patients, and some aspects of the clinical care can clearly be improved.  相似文献   
52.
53.

Background

Researchers evaluating angiomodulating compounds as a part of scientific projects or pre-clinical studies are often confronted with limitations of applied animal models. The rough and insufficient early-stage compound assessment without reliable quantification of the vascular response counts, at least partially, to the low transition rate to clinics.

Objective

To establish an advanced, rapid and cost-effective angiogenesis assay for the precise and sensitive assessment of angiomodulating compounds using zebrafish caudal fin regeneration. It should provide information regarding the angiogenic mechanisms involved and should include qualitative and quantitative data of drug effects in a non-biased and time-efficient way.

Approach & Results

Basic vascular parameters (total regenerated area, vascular projection area, contour length, vessel area density) were extracted from in vivo fluorescence microscopy images using a stereological approach. Skeletonization of the vasculature by our custom-made software Skelios provided additional parameters including “graph energy” and “distance to farthest node”. The latter gave important insights into the complexity, connectivity and maturation status of the regenerating vascular network. The employment of a reference point (vascular parameters prior amputation) is unique for the model and crucial for a proper assessment. Additionally, the assay provides exceptional possibilities for correlative microscopy by combining in vivo-imaging and morphological investigation of the area of interest. The 3-way correlative microscopy links the dynamic changes in vivo with their structural substrate at the subcellular level.

Conclusions

The improved zebrafish fin regeneration model with advanced quantitative analysis and optional 3-way correlative morphology is a promising in vivo angiogenesis assay, well-suitable for basic research and preclinical investigations.  相似文献   
54.
The selection of roosts is considered a critical factor to the survival of Noctilio albiventris. Thus, we located and identified N. albiventris day roosts in the Pantanal, near the Miranda River. We identified four species of tree: Banara arguta, Inga vera, Ocotea diospyrifolia and Vitex cymosa. Additional studies are important to understand the impact of specific requirements in the selection of roosts for Noctilio albiventris and to compare the observed patterns in different environments.  相似文献   
55.
We assessed the relationship between habitat heterogeneity and bird species richness and composition within wetlands of the floodplain of the Middle Paraná River, Argentina. Given the high habitat heterogeneity in these wetland systems, we sought to determine whether (i) there was a positive relationship between bird species richness and habitat heterogeneity; (ii) whether bird species richness was associated with certain types of individual habitat types; (iii) whether there was a pattern of species nestedness and turnover between sites as a function of habitat heterogeneity and composition, respectively; and (iv) whether individual species exhibited associations with habitat heterogeneity. Point counts were used to survey birds at 60 sites. We estimated the area of eight habitat types found within a 200‐m radius from the centre of each site and calculated number and Pielou's evenness of habitat types. These indices, together with area proportion of each habitat type, were used as explanatory factors of bird species richness in linear regression models. Habitat heterogeneity per se rather than area of individual habitat types was a more important predictor of species richness in these fluvial wetlands. Sites with more habitat types supported more bird species. Results showed that individual bird species were associated with different habitat types and, therefore, sites that contained more habitat types contained more species. Number of habitat types accounted for species nestedness between sites whereas composition of habitat types accounted for species turnover between sites. Results suggest that selection of heterogeneous sites by individual species could help explain the positive heterogeneity–species richness relationship. Our findings highlight the importance of habitat heterogeneity per se resulting from flood disturbances in maintaining bird richness in fluvial systems.  相似文献   
56.
Patterns of genomic divergence between hybridizing taxa can be heterogeneous along the genome. Both differential introgression and local adaptation may contribute to this pattern. Here, we analysed two teosinte subspecies, Zea mays ssp. parviglumis and ssp. mexicana, to test whether their divergence has occurred in the face of gene flow and to infer which environmental variables have been important drivers of their ecological differentiation. We generated 9,780 DArTseqTM SNPs for 47 populations, and used an additional data set containing 33,454 MaizeSNP50 SNPs for 49 populations. With these data, we inferred features of demographic history and performed genome wide scans to determine the number of outlier SNPs associated with climate and soil variables. The two data sets indicate that divergence has occurred or been maintained despite continuous gene flow and/or secondary contact. Most of the significant SNP associations were to temperature and to phosphorus concentration in the soil. A large proportion of these candidate SNPs were located in regions of high differentiation that had been identified previously as putative inversions. We therefore propose that genomic differentiation in teosintes has occurred by a process of adaptive divergence, with putative inversions contributing to reduced gene flow between locally adapted populations.  相似文献   
57.
The study aim was to identify consumer segmentation based on nonhuman animal welfare (AW) attitudes and their relationship with demographic features and willingness to pay (WTP) for welfare-friendly products (WFP) in Mexico. Personal interviews were conducted with 843 Mexican consumers who stated they purchased most of the animal products in their home. Respondents were selected using a quota sampling method with age, gender, education, and origin as quota control variables. The multivariate analysis suggested there were three clusters or consumer profiles labeled “skeptical,” “concerned,” and “ethical,” which helped explain the association between AW attitudes, some demographic variables, and WTP for WFP. This study is one of the first to address consumer profiling in Latin America, and the findings could have implications for the commercialization of WFP. Hence, customers should receive information to consider welfare innovations when deciding to purchase animal products. The growth of the WFP food market establishes an element of a far more multifaceted phenomenon of sustainable consumption and support of a new paradigm called responsible marketing in emerging markets such as Mexico.  相似文献   
58.
The stimulation of membrane receptors coupled to the phopholipase C pathway leads to activation of the Ca(2+) release-activated Ca(2+) (CRAC) channels. Recent evidence indicates that ORAI1 is an essential pore subunit of CRAC channels. STIM1 is additionally required for CRAC channel activation. The present study focuses on the genomic organization, tissue expression pattern, and functional properties of the murine ORAI2. Additionally, we report the cloning of the murine ORAI1, ORAI3, and STIM1. Two chromosomal loci were identified for the murine orai2 gene, one containing an intronless gene and a second locus that gives rise to the splice variants ORAI2 long (ORAI2L) and ORAI2 short (ORAI2S). Northern blots revealed a prominent expression of the ORAI2 variants in the brain, lung, spleen, and intestine, while ORAI1, ORAI3, and STIM1 appeared to be near ubiquitously expressed in mice tissues. Specific antibodies detected ORAI2 in RBL 2H3 but not in HEK 293 cells, whereas both cell lines appeared to express ORAI1 and STIM1 proteins. Co-expression experiments with STIM1 and either ORAI1 or ORAI2 variants showed that ORAI2L and ORAI2S enhanced substantially CRAC current densities in HEK 293 but were ineffective in RBL 2H3 cells, whereas ORAI1 strongly amplified CRAC currents in both cell lines. Thus, the capability of ORAI2 variants to form CRAC channels depends strongly on the cell background. Additionally, CRAC channels formed by ORAI2S were strongly sensitive to inactivation by internal Ca(2+). When co-expressed with STIM1 and ORAI1, ORAI2S apparently plays a negative dominant role in the formation of CRAC channels.  相似文献   
59.
The muO-conotoxins MrVIA and MrVIB are 31-residue peptides from Conus marmoreus, belonging to the O-superfamily of conotoxins with three disulfide bridges. They have attracted attention because they are inhibitors of tetrodotoxin-insensitive voltage-gated sodium channels (Na(V)1.8) and could therefore serve as lead structure for novel analgesics. The aim of this study was to elucidate the molecular mechanism by which muO-conotoxins affect Na(V) channels. Rat Na(V)1.4 channels and mutants thereof were expressed in mammalian cells and were assayed with the whole-cell patch-clamp method. Unlike for the M-superfamily mu-conotoxin GIIIA from Conus geographus, channel block by MrVIA was strongly diminished after activating the Na(V) channels by depolarizing voltage steps. Searching for the source of this voltage dependence, the gating charges in all four-voltage sensors were reduced by site-directed mutagenesis showing that alterations of the voltage sensor in domain-2 have the strongest impact on MrVIA action. These results, together with previous findings that the effect of MrVIA depends on the structure of the pore-loop in domain-3, suggest a functional similarity with scorpion beta-toxins. In fact, MrVIA functionally competed with the scorpion beta-toxin Ts1 from Tityus serrulatus, while it did not show competition with mu-GIIIA. Ts1 and mu-GIIIA did not compete either. Thus, similar to scorpion beta-toxins, muO-conotoxins are voltage-sensor toxins targeting receptor site-4 on Na(V) channels. They "block" Na(+) flow most likely by hindering the voltage sensor in domain-2 from activating and, hence, the channel from opening.  相似文献   
60.
BACKGROUND: Classification and analysis of congenital heart defects (CHD) in etiologic studies is particularly challenging because of diversity of cardiac phenotypes and underlying developmental mechanisms. We describe an approach to classification for risk assessment of CHD based on developmental and epidemiologic considerations, and apply it to data from the National Birth Defect Prevention Study (NBDPS). METHODS: The classification system incorporated the three dimensions of cardiac phenotype, cardiac complexity, and extracardiac anomalies. The system was designed to facilitate the assessment of simple isolated defects and common associations. A team with cardiologic expertise applied the system to a large sample from the NBDPS. RESULTS: Of the 4,703 cases of CHDs in the NBDPS with birth years 1997 through 2002, 63.6% were simple, isolated cases. Specific associations of CHDs represented the majority of the remainder. The mapping strategy generated relatively large samples for most cardiac phenotypes and provided enough detail to isolate important subgroups of CHDs that may differ by etiology or mechanism. CONCLUSIONS: Classification of CHDs that considers cardiac and extracardiac phenotypes is practically feasible, and yields manageable groups of well-characterized phenotypes. Although best suited for large studies, this approach to classification and analysis can be a flexible and powerful tool in many types of etiologic studies of heart defects.  相似文献   
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