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1.
Olendzenski L Liu L Zhaxybayeva O Murphey R Shin DG Gogarten JP 《Journal of molecular evolution》2000,51(6):587-599
Members of the Deinococcaceae (e.g., Thermus, Meiothermus, Deinococcus) contain A/V-ATPases typically found in Archaea or Eukaryotes which were probably acquired by horizontal gene transfer. Two methods were used to quantify the extent to which archaeal or eukaryotic genes have been acquired by this lineage. Screening of a Meiothermus ruber library with probes made against Thermoplasma acidophilum DNA yielded a number of clones which hybridized more strongly than background. One of these contained the prolyl tRNA synthetase (RS) gene. Phylogenetic analysis shows the M. ruber and D. radiodurans prolyl RS to be more closely related to archaeal and eukaryal forms of this gene than to the typical bacterial type. Using a bioinformatics approach, putative open reading frames (ORFs) from the prerelease version of the D. radiodurans genome were screened for genes more closely related to archaeal or eukaryotic genes. Putative ORFs were searched against representative genomes from each of the three domains using automated BLAST. ORFs showing the highest matches against archaeal and eukaryotic genes were collected and ranked. Among the top-ranked hits were the A/V-ATPase catalytic and noncatalytic subunits and the prolyl RS genes. Using phylogenetic methods, ORFs were analyzed and trees assessed for evidence of horizontal gene transfer. Of the 45 genes examined, 20 showed topologies in which D. radiodurans homologues clearly group with eukaryotic or archaeal homologues, and 17 additional trees were found to show probable evidence of horizontal gene transfer. Compared to the total number of ORFs in the genome, those that can be identified as having been acquired from Archaea or Eukaryotes are relatively few (approximately 1%), suggesting that interdomain transfer is rare. 相似文献
2.
Wouter Coppieters Juliette Riquet Juan-José Arranz Paulette Berzi Nadine Cambisano Bernard Grisart Latifa Karim Fabienne Marcq Laurence Moreau Carine Nezer Patricia Simon Pascal Vanmanshoven Danny Wagenaar Michel Georges 《Mammalian genome》1998,9(7):540-544
A whole genome scan was undertaken in a granddaughter design comprising 1158 progeny-tested bulls in order to map QTL influencing
milk yield and composition. In this paper we report the identification of a locus on the centromeric end of bovine Chromosome
(Chr) 14, with major effect on fat and protein percentage as well as milk yield. The genuine nature of this QTL was verified
using the grand2-daughter design, that is, by tracing the segregating QTL alleles from heterozygous grandsires to their maternal grandsons
and confirming the predicted QTL allele substitution effect.
Received: 30 December 1997 / Accepted: 21 February 1998 相似文献
3.
Juan G. Navedo David Arranz Alejandro G. Herrera Pablo Salmón José A. Juanes José A. Masero 《Biodiversity and Conservation》2013,22(9):1895-1907
Coastal pastures are common agroecosystems adjacent to estuarine areas that can provide valuable habitat for wildlife, particularly for migratory shorebirds. Disentangling the factors that influence coastal pasture use by wintering shorebirds will provide new insights into its role for buffering human disturbances and habitat loss in intertidal areas. We examined whether numbers of two shorebirds (Eurasian curlew and Black-tailed godwit) foraging actively on coastal pastures was affected by weather conditions, tidal stage (low/high tide) and number of harvesters at intertidal areas throughout winter. Both species frequently used coastal pastures and most individuals foraged actively there. The average percentage of the total wintering population of curlews and godwits foraging on coastal pastures was 27.4 and 7.8 %, respectively, and was significantly higher during high tide compared to low tide. The number of harvesters on mudflats also had a positive significant effect in explaining the presence of curlews, and to a lesser extent for godwits, on coastal pastures, and accumulated rainfall had a positive effect for both species too. These supratidal areas were consistently used as alternative foraging grounds during low tide by curlews, as well as supplementary foraging areas during high tide by wintering populations of both large shorebirds. By supplementary foraging, wintering curlews, and probably godwits, seemed to compensate for a negative effect of the presence of harvesters on their foraging activity. We recommend managing of those coastal agricultural fields adjacent to intertidal foraging grounds in order to increase the availability of supratidal foraging habitats for declining shorebird populations. These habitats may thus have a beneficial role in sustaining populations of wintering shorebirds, but further studies are needed to estimate if birds can compensate for any shortfall in daily energy budget by supplementary foraging on coastal pastures, thus providing insights into whether they are involved in large-scale population regulation of migratory birds. 相似文献
4.
Jose L. López-Campos Maria Abad Arranz Carmen Calero-Acu?a Fernando Romero-Valero Ruth Ayerbe-García Antonio Hidalgo-Molina Ricardo I. Aguilar-Pérez-Grovas Francisco García-Gil Francisco Casas-Maldonado Laura Caballero-Ballesteros María Sánchez-Palop Dolores Pérez-Tejero Alejandro Segado Jose Calvo-Bonachera Bárbara Hernández-Sierra Adolfo Doménech Macarena Arroyo-Varela Francisco González-Vargas Juan J. Cruz-Rueda 《PloS one》2016,11(3)
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5.
6.
7.
A new fourier transform approach for protein coding measure based on the format of the Z curve 总被引:2,自引:0,他引:2
MOTIVATION: At the core of most protein gene-finding algorithms are the
coding measures used to make a decision on coding/non-coding. Of the
protein coding measures, the Fourier measure is one of the most important.
However, due to the limited length of the windows usually used, the
accuracy of the measure is not satisfactory. This paper is devoted to
improving the accuracy by lengthening the sequence to amplify the
periodicity of 3 in the coding regions. RESULTS: A new algorithm is
presented called the lengthen-shuffle Fourier transform algorithm. For the
same window length, the percentage accuracy of the new algorithm is 6-7%
higher than that of the ordinary Fourier transform algorithm. The resulting
percentage accuracy (average of specificity and sensitivity) of the new
measure is 84.9% for the window length 162 bp. AVAILABILITY: The program is
available on request fromC.- T. Zhang. Contact: ctzhang@tju.edu.cn
相似文献
8.
Size‐based interactions and trophic transfer efficiency are modified by fish predation and cyanobacteria blooms in Lake Mývatn,Iceland 下载免费PDF全文
Zeynep Ersoy Erik Jeppesen Serena Sgarzi Ignasi Arranz Miguel Cañedo‐Argüelles Xavier D. Quintana Frank Landkildehus Torben L. Lauridsen Mireia Bartrons Sandra Brucet 《Freshwater Biology》2017,62(11):1942-1952
9.
Gomariz RP Arranz A Juarranz Y Gutierrez-Cañas I Garcia-Gomez M Leceta J Martínez C 《Peptides》2007,28(9):1825-1832
The contribution of VIP immune functions to the regulation of homeostasis and health is well known. Modulation of immune responses through new therapeutics is one of the main goals of physicians and scientists seeking to control inflammatory/autoimmune diseases in humans. Initial therapeutic strategies targeted adaptive immune responses; discovery of Toll-like receptors (TLR) has widened the horizon to include targeting the innate immune system. In this review we have summarized recent information about VIP modulation of TLR function, and we suggest that VIP represents a new therapeutic option in the management of several pathologies. 相似文献
10.
Costa MA Elesgaray R Caniffi C Fellet A Arranz C 《Biochemical and biophysical research communications》2007,359(1):180-186
The aims were to evaluate the role of cardiovascular nitric oxide (NO)-system in C-type natriuretic peptide (CNP) actions and to investigate receptor types and signaling pathways involved in this interaction. Wistar rats were infused with saline or CNP. Mean arterial pressure (MAP) and nitrites and nitrates (NOx) excretion were determined. NO synthase (NOS) activity and NOS expression (Western blot) were analyzed in atria, ventricle and aorta. CNP decreased MAP and increased NOx excretion. CNP estimulated NOS activity, inducing no changes on cardiac and vascular endothelial NOS expression. NOS activity induced by CNP was abolished by suramin and calmidazoliumand but it is not modified by anantin. CNP would interact with NPR-C receptor coupled via G proteins leading to the activation Ca(2+)-calmodulin dependent endothelial NOS, increasing NO production which would induce the reduction in cardiac myocyte contractility and ANP synthesis and secretion in right atria and the relaxation of vascular smooth muscle. 相似文献