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951.
Alejandro A Diaz Farbod N Rahaghi James C Ross Rola Harmouche Juerg Tschirren Raul San José Estépar George R Washko for the COPD Gene investigators 《Respiratory research》2015,16(1)
Background
Computed tomographic (CT) airway lumen narrowing is associated with lower lung function. Although volumetric CT measures of airways (wall volume [WV] and lumen volume [LV]) compared to cross sectional measures can more accurately reflect bronchial morphology, data of their use in never smokers is scarce. We hypothesize that native tracheobronchial tree morphology as assessed by volumetric CT metrics play a significant role in determining lung function in normal subjects. We aimed to assess the relationships between airway size, the projected branching generation number (BGN) to reach airways of <2mm lumen diameter –the site for airflow obstruction in smokers- and measures of lung function including forced expiratory volume in 1 second (FEV1) and forced expiratory flow between 25% and 75% of vital capacity (FEF 25–75).Methods
We assessed WV and LV of segmental and subsegmental airways from six bronchial paths as well as lung volume on CT scans from 106 never smokers. We calculated the lumen area ratio of the subsegmental to segmental airways and estimated the projected BGN to reach a <2mm-lumen-diameter airway assuming a dichotomized tracheobronchial tree model. Regression analysis was used to assess the relationships between airway size, BGN, FEF 25–75, and FEV1.Results
We found that in models adjusted for demographics, LV and WV of segmental and subsegmental airways were directly related to FEV1 (P <0.05 for all the models). In adjusted models for age, sex, race, LV and lung volume or height, the projected BGN was directly associated with FEF 25–75 and FEV1 (P = 0.001) where subjects with lower FEV1 had fewer calculated branch generations between the subsegmental bronchus and small airways. There was no association between airway lumen area ratio and lung volume.Conclusion
We conclude that in never smokers, those with smaller central airways had lower airflow and those with lower airflow had less parallel airway pathways independent of lung size. These findings suggest that variability in the structure of the tracheobronchial tree may influence the risk of developing clinically relevant smoking related airway obstruction.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0181-y) contains supplementary material, which is available to authorized users. 相似文献952.
Bruna Zafalon‐Silva Frederico Acio Carvalho Soares Saulo Petinatti Pavarini Miúriel de Aquino Goulart Gustavo Geraldo Medina Snel Flix Hilrio Diaz Gonzlez Dayana Bittencourt Vaz Bruna Correa Lopes Moira Ansolch da Silva Oliveira Marcelo Meller Alievi 《Journal of medical primatology》2019,48(2):129-132
A brown howler monkey (Alouatta guariba clamitans) was presented with lethargy, hyporexia, cough and heart murmur. The complementary tests and necropsy revealed pleuropneumonia, bacterial endocarditis and interventricular septal defect. To the best of our knowledge, this is the first report of increased cardiac troponin I levels in this species. 相似文献
953.
William R. Miller Truc T. Tran Lorena Diaz Rafael Rios Ayesha Khan Jinnethe Reyes Amy G. Prater Diana Panesso Yousif Shamoo Cesar A. Arias 《Molecular microbiology》2019,111(3):811-824
The lipopeptide antibiotic daptomycin (DAP) is a key drug against serious enterococcal infections, but the emergence of resistance in the clinical setting is a major concern. The LiaFSR system plays a prominent role in the development of DAP resistance (DAP‐R) in enterococci, and blocking this stress response system has been proposed as a novel therapeutic strategy. In this work, we identify LiaR‐independent pathways in Enterococcus faecalis that regulate cell membrane adaptation in response to antibiotics. We adapted E. faecalis OG1RF (a laboratory strain) and S613TM (a clinical strain) lacking liaR to increasing concentrations of DAP, leading to the development of DAP‐R and elevated MICs to bacitracin and ceftriaxone. Whole genome sequencing identified changes in the YxdJK two‐component regulatory system and a putative fatty acid kinase (dak) in both DAP‐R strains. Deletion of the gene encoding the YxdJ response regulator in both the DAP‐R mutant and wild‐type OG1RF decreased MICs to DAP, even when a functional LiaFSR system was present. Mutations in dak were associated with slower growth, decreased membrane fluidity and alterations of cell morphology. These findings suggest that overlapping stress response pathways can provide protection against antimicrobial peptides in E. faecalis at a significant cost in bacterial fitness. 相似文献
954.
955.
956.
Aaron C. Hartmann Kristen L. Marhaver Anke Klueter Michael T. Lovci Collin J. Closek Erika Diaz Valrie F. Chamberland Frederick I. Archer Dimitri D. Deheyn Mark J. A. Vermeij Mnica Medina 《Molecular ecology》2019,28(1):141-155
Theory suggests that the direct transmission of beneficial endosymbionts (mutualists) from parents to offspring (vertical transmission) in animal hosts is advantageous and evolutionarily stable, yet many host species instead acquire their symbionts from the environment (horizontal acquisition). An outstanding question in marine biology is why some scleractinian corals do not provision their eggs and larvae with the endosymbiotic dinoflagellates that are necessary for a juvenile's ultimate survival. We tested whether the acquisition of photosynthetic endosymbionts (family Symbiodiniaceae) during the planktonic larval stage was advantageous, as is widely assumed, in the ecologically important and threatened Caribbean reef‐building coral Orbicella faveolata. Following larval acquisition, similar changes occurred in host energetic lipid use and gene expression regardless of whether their symbionts were photosynthesizing, suggesting the symbionts did not provide the energetic benefit characteristic of the mutualism in adults. Larvae that acquired photosymbionts isolated from conspecific adults on their natal reef exhibited a reduction in swimming, which may interfere with their ability to find suitable settlement substrate, and also a decrease in survival. Larvae exposed to two cultured algal species did not exhibit differences in survival, but decreased their swimming activity in response to one species. We conclude that acquiring photosymbionts during the larval stage confers no advantages and can in fact be disadvantageous to this coral host. The timing of symbiont acquisition appears to be a critical component of a host's life history strategy and overall reproductive fitness, and this timing itself appears to be under selective pressure. 相似文献
957.
Jiajie Wei Rigel J. Kishton Matthew Angel Crystal S. Conn Nicole Dalla-Venezia Virginie Marcel Anne Vincent Frédéric Catez Sabrina Ferré Lilia Ayadi Virginie Marchand Devin Dersh James S. Gibbs Ivaylo P. Ivanov Nathan Fridlyand Yohann Couté Jean-Jacques Diaz Shu-Bing Qian Jonathan W. Yewdell 《Molecular cell》2019,73(6):1162-1173.e5
958.
Cristina Romero‐Diaz Julio A. Rivera Alison G. Ossip‐Drahos Jos Jaime Zúiga‐Vega Cuauhcihuatl Vital‐García Diana K. Hews Emília P. Martins 《Journal of evolutionary biology》2019,32(4):320-330
Colour signalling traits are often lost over evolutionary time, perhaps because they increase vulnerability to visual predators or lose relevance in terms of sexual selection. Here, we used spectrometric and phylogenetic comparative analyses to ask whether four independent losses of a sexually selected blue patch are spectrally similar, and whether these losses equate to a decrease in conspicuousness or to loss of a signal. We found that patches were lost in two distinct ways: either increasing reflectance primarily at very long or at very short wavelengths, and that species with additional colour elements (UV, green and pink) may be evolutionary intermediates. In addition, we found that patch spectral profiles of all species were closely aligned with visual receptors in the receiver's retina. We found that loss of the blue patch makes males less conspicuous in terms of chromatic conspicuousness, but more conspicuous in terms of achromatic contrast, and that sexual dimorphism often persists regardless of patch loss. Dorsal surfaces were considerably more cryptic than were ventral surfaces, and species in which male bellies were the most similar in conspicuousness to their dorsal surfaces were also the most sexually dimorphic. These results emphasize the consistent importance of sexual selection and its flexible impact on different signal components through evolutionary time. 相似文献
959.
Genome Sequencing and Analysis of Geographically Diverse Clinical Isolates of Herpes Simplex Virus 2
Ruchi M. Newman Susanna L. Lamers Brian Weiner Stuart C. Ray Robert C. Colgrove Fernando Diaz Lichen Jing Kening Wang Sakina Saif Sarah Young Matthew Henn Oliver Laeyendecker Aaron A. R. Tobian Jeffrey I. Cohen David M. Koelle Thomas C. Quinn David M. Knipe 《Journal of virology》2015,89(16):8219-8232
960.
Opposite selection on behavioural types by active and passive fishing gears in a simulated guppy Poecilia reticulata fishery
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This study assessed whether fishing gear was selective on behavioural traits, such as boldness and activity, and how this was related with a productivity trait, growth. Female guppies Poecilia reticulata were screened for their behaviour on the shy–bold axis and activity, and then tested whether they were captured differently by passive and active fishing gear, here represented by a trap and a trawl. Both gears were selective on boldness; bold individuals were caught faster by the trap, but escaped the trawl more often. Boldness and gear vulnerability showed weak correlations with activity and growth. The results draw attention to the importance of the behavioural dimension of fishing: selective fishing on behavioural traits will change the trait composition of the population, and might eventually affect resilience and fishery productivity. 相似文献