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61.
Olivier Maurin Artemis Anest Sidonie Bellot Edward Biffin Grace Brewer Tristan Charles-Dominique Robyn S. Cowan Steven Dodsworth Niroshini Epitawalage Berta Gallego Augusto Giaretta Renato Goldenberg Deise J.P. Gonçalves Shirley Graham Peter Hoch Fiorella Mazine Yee Wen Low Catherine McGinnie Fabián A. Michelangeli Sarah Morris Darin S. Penneys Oscar Alejandro Pérez Escobar Yohan Pillon Lisa Pokorny Gustavo Shimizu Vanessa G. Staggemeier Andrew H. Thornhill Kyle W. Tomlinson Ian M. Turner Thais Vasconcelos Peter G. Wilson Alexandre R. Zuntini William J. Baker Félix Forest Eve Lucas 《American journal of botany》2021,108(7):1087-1111
62.
Aetosaur specimens from Howard County, Texas, USA, namedTypothorax meadei by Sawin (1947) represent a new genus here namedLongosuchus (type and only species -L. meadei). Longosu-chus is characterised by the possession of seven dentary teeth, a dentary excluded from the ventral margin of the lateral mandibular fenestra and by the angular, spinose lateral scutes throughout the dorsal region with lateral horns which have faceted sides.Longosuchus is found in mid-late Carnian strata in Texas, New Mexico and North Carolina, USA. Aetosaurs can be used to distinguish three successive biochrons in Late Triassic strata of the American Southwest, which are, in ascending order of age, theLongosuchus biochron, theStagonolepis biochron and theTypothorax biochron. 相似文献
63.
Oral Antibiotic Treatment of Mice Exacerbates the Disease Severity of Multiple Flavivirus Infections
64.
Francesca Spyrakis Fátima Lucas Axel Bidon-Chanal Cristiano Viappiani Victor Guallar F. Javier Luque 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(9):1957-1967
This study reports a comparative analysis of the topological properties of inner cavities and the intrinsic dynamics of non-symbiotic hemoglobins AHb1 and AHb2 from Arabidopsis thaliana. The two proteins belong to the 3/3 globin fold and have a sequence identity of about 60%. However, it is widely assumed that they have distinct physiological roles. In order to investigate the structure–function relationships in these proteins, we have examined the bis-histidyl and ligand-bound hexacoordinated states by atomistic simulations using in silico structural models. The results allow us to identify two main pathways to the distal cavity in the bis-histidyl hexacoordinated proteins. Nevertheless, a larger accessibility to small gaseous molecules is found in AHb2. This effect can be attributed to three factors: the mutation Leu35(AHb1) → Phe32(AHb2), the enhanced flexibility of helix B, and the more favorable energetic profile for ligand migration to the distal cavity. The net effect of these factors would be to facilitate the access of ligands, thus compensating the preference for the fully hexacoordination of AHb2, in contrast to the equilibrium between hexa- and pentacoordinated species in AHb1. On the other hand, binding of the exogenous ligand introduces distinct structural changes in the two proteins. A well-defined tunnel is formed in AHb1, which might be relevant to accomplish the proposed NO detoxification reaction. In contrast, no similar tunnel is found in AHb2, which can be ascribed to the reduced flexibility of helix E imposed by the larger number of salt bridges compared to AHb1. This feature would thus support the storage and transport functions proposed for AHb2. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins. 相似文献
65.
Descriptive analysis of high birth prevalence rate geographical clusters of congenital anomalies in South America 下载免费PDF全文
66.
Cavin K. Ward-Caviness Lucas M. Neas Colette Blach Carol S. Haynes Karen LaRocque-Abramson Elizabeth Grass Elaine Dowdy Robert B. Devlin David Diaz-Sanchez Wayne E. Cascio Marie Lynn Miranda Simon G. Gregory Svati H. Shah William E. Kraus Elizabeth R. Hauser 《PloS one》2016,11(4)
There is a growing literature indicating that genetic variants modify many of the associations between environmental exposures and clinical outcomes, potentially by increasing susceptibility to these exposures. However, genome-scale investigations of these interactions have been rarely performed particularly in the case of air pollution exposures. We performed race-stratified genome-wide gene-environment interaction association studies on European-American (EA, N = 1623) and African-American (AA, N = 554) cohorts to investigate the joint influence of common single nucleotide polymorphisms (SNPs) and residential exposure to traffic (“traffic exposure”)—a recognized vascular disease risk factor—on peripheral arterial disease (PAD). Traffic exposure was estimated via the distance from the primary residence to the nearest major roadway, defined as the nearest limited access highways or major arterial. The rs755249-traffic exposure interaction was associated with PAD at a genome-wide significant level (P = 2.29x10-8) in European-Americans. Rs755249 is located in the 3’ untranslated region of BMP8A, a member of the bone morphogenic protein (BMP) gene family. Further investigation revealed several variants in BMP genes associated with PAD via an interaction with traffic exposure in both the EA and AA cohorts; this included interactions with non-synonymous variants in BMP2, which is regulated by air pollution exposure. The BMP family of genes is linked to vascular growth and calcification and is a novel gene family for the study of PAD pathophysiology. Further investigation of BMP8A using the Genotype Tissue Expression Database revealed multiple variants with nominally significant (P < 0.05) interaction P-values in our EA cohort were significant BMP8A eQTLs in tissue types highlight relevant for PAD such as rs755249 (tibial nerve, eQTL P = 3.6x10-6) and rs1180341 (tibial artery, eQTL P = 5.3x10-6). Together these results reveal a novel gene, and possibly gene family, associated with PAD via an interaction with traffic air pollution exposure. These results also highlight the potential for interactions studies, particularly at the genome scale, to reveal novel biology linking environmental exposures to clinical outcomes. 相似文献
67.
Meisha Holloway‐Phillips Lucas A. Cernusak Margaret Barbour Xin Song Alexander Cheesman Niels Munksgaard Hilary Stuart‐Williams Graham D. Farquhar 《Plant, cell & environment》2016,39(11):2414-2427
The process of evaporation results in the fractionation of water isotopes such that the lighter 16O isotope preferentially escapes the gas phase leaving the heavier 18O isotope to accumulate at the sites of evaporation. This applies to transpiration from a leaf with the degree of fractionation dependent on a number of environmental and physiological factors that are well understood. Nevertheless, the 18O enrichment of bulk leaf water is often less than that predicted for the sites of evaporation. The advection of less enriched water in the transpiration stream has been suggested to limit the back diffusion of enriched evaporative site water (Péclet effect); however, evidence for this effect has been varied. In sampling across a range of species with different vein densities and saturated water contents, we demonstrate the importance of accounting for the relative ‘pool’ sizes of the vascular and mesophyll water for the interpretation of a Péclet effect. Further, we provide strong evidence for a Péclet signal within the xylem that if unaccounted for can lead to confounding of the estimated enrichment within the mesophyll water. This has important implications for understanding variation in the effective path length of the mesophyll and hence potentially the δ18O of organic matter. 相似文献
68.
Raquel Chatkin José Miguel Chatkin Lucas Spanemberg Daniela Casagrande Mario Wagner Cláudio Mottin 《PloS one》2015,10(5)
IntroductionWhile the association between cigarette smoking and abdominal fat has been well studied in normal and overweight patients, data regarding the influence of tobacco use in patients with morbid obesity remain scarce. The aim of this study is to evaluate body fat distribution in morbidly obese smokers.MethodsWe employed a cross-sectional study and grouped severely obese patients (body mass index [BMI] >40 kg/m2 or >35 kg/m2 with comorbidities) according to their smoking habits (smokers or non-smokers). We next compared the anthropometrical measurements and body composition data (measured by electric bioimpedance) of both groups. We analyzed the effect of smoking on body composition variables using univariate and multiple linear regression (MLR); differences are presented as regression coefficients (b) and their respective 95% confidence intervals.ResultsWe included 536 morbidly obese individuals, 453 (84.5%) non-smokers and 83 (15.5%) smokers. Male smokers had a higher BMI (b=3.28 kg/m2, p=0.036), larger waist circumference (b=6.07 cm, p=0.041) and higher percentage of body fat (b=2.33%, p=0.050) than non-smokers. These differences remained significant even after controlling for confounding factors. For females, the only significant finding in MLR was a greater muscle mass among smokers (b=1.34kg, p=0.028). No associations were found between tobacco load measured in pack-years and anthropometric measures or body composition.DiscussionPositive associations between smoking and BMI, and waist circumference and percentage of body fat, were found among male morbidly obese patients, but not among females. To the best of our knowledge, this study is the first investigation of these aspects in morbidly obese subjects. We speculate that our findings may indicate that the coexistence of morbid obesity and smoking helps to explain the more serious medical conditions, particularly cardiovascular diseases and neoplasms, seen in these patients. 相似文献
69.
Ram lambs and bull calves were immunized against LH-RH by injections given in weeks 0, 6, 12 and 28 (ram lambs, week 0 = 16 to 20 weeks of age) and weeks 0, 6, 12 and 18 (bull calves, week 0 = approximately 4 weeks of age). The testis size of LH-RH-immunized animals was significantly less than that of controls from week 13 onwards in ram lambs and from week 15 onwards in bull calves. When ram lambs were sampled in week 17 and bull calves in week 20, mean plasma gonadotrophin and testosterone concentrations were consistently lower in LH-RH-immunized animals than in controls. Single intravenous injection of synthetic LH-RH or an analogue of LH-RH in week 27 failed to induce LH or testosterone responses in LH-RH-immunized ram lambs. Motile semen samples could not be obtained from any of the LH-RH-immunized ram lambs in weeks 24, 25 and 26 or from 7 of 10 in week 72, but samples of moderate motility were obtained in week 72 from three rams in which LH-RH antibody titres had fallen. No attempt was made to obtain semen from bull calves. After castration there was no increase in plasma LH in LH-RH-immunized rams and only a small increase in LH-RH-immunized bull calves. Mean testis weight was significantly lower in LH-RH-immunized animals than in controls of both species. Thus the normal development of the reproductive system in ram lambs and bull calves was blocked by active immunization against LH-RH. Some evidence was obtained for natural reversal of the effects with time and falling antibody titres. These findings demonstrate the potential of LH-RH immunization as an alternative to castration. 相似文献
70.