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141.
Jordi Sala Stéphanie Gascón David Cunillera-Montcusí Miguel Alonso Francisco Amat Luís Cancela da Fonseca Margarida Cristo Margarita Florencio Juan García-de-Lomas Margarida Machado Maria Rosa Miracle Alexandre Miró José Luis Pérez-Bote Joan Lluís Pretus Florent Prunier Javier Ripoll Juan Rueda María Sahuquillo Laura Serrano Marc Ventura David Verdiell-Cubedo Dani Boix 《Hydrobiologia》2017,784(1):81-91
The deficiency in the distributional data of invertebrate taxa is one of the major impediments acting on the bias towards the low awareness of its conservation status. The present study sets a basic framework to understand the large branchiopods distribution in the Iberian Peninsula and Balearic Islands. Since the extensive surveys performed in the late 1980s, no more studies existed updating the information for the whole studied area. The present study fills the gap, gathering together all available information on large branchiopods distribution since 1995, and analysing the effect of human population density and several landscape characteristics on their distribution, taking into consideration different spatial scales (100 m, 1 km and 10 km). In overall, 28 large branchiopod taxa (17 anostracans, 7 notostracans and 4 spinicaudatans) are known to occur in the area. Approximately 30% of the sites hosted multiple species, with a maximum of 6 species. Significant positive co-occurring species pairs were found clustered together, forming 4 different associations of large branchiopod species. In general, species clustered in the same group showed similar responses to analysed landscape characteristics, usually showing a better fit at higher spatial scales. 相似文献
142.
Sessions A Burke E Presting G Aux G McElver J Patton D Dietrich B Ho P Bacwaden J Ko C Clarke JD Cotton D Bullis D Snell J Miguel T Hutchison D Kimmerly B Mitzel T Katagiri F Glazebrook J Law M Goff SA 《The Plant cell》2002,14(12):2985-2994
A collection of Arabidopsis lines with T-DNA insertions in known sites was generated to increase the efficiency of functional genomics. A high-throughput modified thermal asymmetric interlaced (TAIL)-PCR protocol was developed and used to amplify DNA fragments flanking the T-DNA left borders from approximately 100000 transformed lines. A total of 85108 TAIL-PCR products from 52964 T-DNA lines were sequenced and compared with the Arabidopsis genome to determine the positions of T-DNAs in each line. Predicted T-DNA insertion sites, when mapped, showed a bias against predicted coding sequences. Predicted insertion mutations in genes of interest can be identified using Arabidopsis Gene Index name searches or by BLAST (Basic Local Alignment Search Tool) search. Insertions can be confirmed by simple PCR assays on individual lines. Predicted insertions were confirmed in 257 of 340 lines tested (76%). This resource has been named SAIL (Syngenta Arabidopsis Insertion Library) and is available to the scientific community at www.tmri.org. 相似文献
143.
144.
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
145.
Ca2+ fluxes through ionotropic glutamate receptors regulate a variety of developmental processes, including neurite outgrowth and naturally occurring cell death. In the CNS, NMDA receptors were originally thought to be the sole source of Ca2+ influx through glutamate receptors; however, AMPA receptors also allow a significant influx of Ca2+ ions. The Ca2+ permeability of AMPA receptors is regulated by the insertion of one or more edited GluR2 subunits. In this study, we tested the possibility that changes in GluR2 expression regulate the Ca2+ permeability of AMPA receptors during a critical period of neuronal development in chick lumbar motoneurons. GluR2 expression is absent between embryonic day (E) 5 and E7, but increases significantly by E8 in the chick ventral spinal cord. Increased GluR2 protein expression is correlated with parallel changes in GluR2 mRNA in the motoneuron pool. Electrophysiological recordings of kainate-evoked currents indicate a significant reduction in the Ca2(+)-permeability of AMPA receptors between E6 and E11. Kainate-evoked currents were sensitive to the AMPA receptor blocker GYKI 52466. Application of AMPA or kainate generates a significant increase in the intracellular Ca2+ concentration in E6 spinal motoneurons, but generates a small response in older neurons. Changes in the Ca(2+)-permeability of AMPA receptors are not mediated by age-dependent changes in the editing pattern of GluR2 subunits. These findings raise the possibility that Ca2+ influx through Ca(2+)-permeable AMPA receptors plays an important role during early embryonic development in chick spinal motoneurons. 相似文献
146.
147.
Admixture in Mexico City: implications for admixture mapping of Type 2 diabetes genetic risk factors
Martinez-Marignac VL Valladares A Cameron E Chan A Perera A Globus-Goldberg R Wacher N Kumate J McKeigue P O'Donnell D Shriver MD Cruz M Parra EJ 《Human genetics》2007,120(6):807-819
Admixture mapping is a recently developed method for identifying genetic risk factors involved in complex traits or diseases
showing prevalence differences between major continental groups. Type 2 diabetes (T2D) is at least twice as prevalent in Native
American populations as in populations of European ancestry, so admixture mapping is well suited to study the genetic basis
of this complex disease. We have characterized the admixture proportions in a sample of 286 unrelated T2D patients and 275
controls from Mexico City and we discuss the implications of the results for admixture mapping studies. Admixture proportions
were estimated using 69 autosomal ancestry-informative markers (AIMs). Maternal and paternal contributions were estimated
from geographically informative mtDNA and Y-specific polymorphisms. The average proportions of Native American, European and,
West African admixture were estimated as 65, 30, and 5%, respectively. The contributions of Native American ancestors to maternal
and paternal lineages were estimated as 90 and 40%, respectively. In a logistic model with higher educational status as dependent
variable, the odds ratio for higher educational status associated with an increase from 0 to 1 in European admixture proportions
was 9.4 (95%, credible interval 3.8–22.6). This association of socioeconomic status with individual admixture proportion shows
that genetic stratification in this population is paralleled, and possibly maintained, by socioeconomic stratification. The
effective number of generations back to unadmixed ancestors was 6.7 (95% CI 5.7–8.0), from which we can estimate that genome-wide
admixture mapping will require typing about 1,400 evenly distributed AIMs to localize genes underlying disease risk between
populations of European and Native American ancestry. Sample sizes of about 2,000 cases will be required to detect any locus
that contributes an ancestry risk ratio of at least 1.5. 相似文献
148.
Citlali Trueta Sergio Snchez‐Armass Miguel A. Morales Francisco F. De‐Miguel 《Developmental neurobiology》2004,61(3):309-316
We analyzed the contribution of calcium (Ca2+)‐induced Ca2+ release to somatic secretion in serotonergic Retzius neurons of the leech. Somatic secretion was studied by the incorporation of fluorescent dye FM1‐43 upon electrical stimulation with trains of 10 impulses and by electron microscopy. Quantification of secretion with FM1‐43 was made in cultured neurons to improve optical resolution. Stimulation in the presence of FM1‐43 produced a frequency‐dependent number of fluorescent spots. While a 1‐Hz train produced 19.5 ± 5.0 spots/soma, a 10‐Hz train produced 146.7 ± 20.2 spots/soma. Incubation with caffeine (10 mM) to induce Ca2+ release from intracellular stores without electrical stimulation and external Ca2+, produced 168 ± 21.7 spots/soma. This staining was reduced by 49% if neurons were preincubated with the Ca2+‐ ATPase inhibitor thapsigargin (200 nM). Moreover, in neurons stimulated at 10 Hz in the presence of ryanodine (100 μM) to block Ca2+‐induced Ca2+ release, FM1‐43 staining was reduced by 42%. In electron micrographs of neurons at rest or stimulated at 1 Hz in the ganglion, endoplasmic reticulum lay between clusters of dense core vesicles and the plasma membrane. In contrast, in neurons stimulated at 20 Hz, the vesicle clusters were apposed to the plasma membrane and flanked by the endoplasmic reticulum. These results suggest that Ca2+‐induced Ca2+ release produces vesicle mobilization and fusion in the soma of Retzius neurons, and supports the idea that neuronal somatic secretion shares common mechanisms with secretion by excitable endocrine cells. © 2004 Wiley Periodicals, Inc. J Neurobiol, 2004 相似文献
149.
We model the optimal foraging strategies for 2 nectarivore species,differing in the length of their proboscis, that exploit thenectar provided by 2 types of flowers, differing in the depthsof their corollas. When like flowers appear in clumps, nectarivoresmust decide whether to forage at a patch of deep or shallowflowers. If nectarivores forage optimally, at least one flowertype will be used by a single nectarivore species. Long-tonguedforagers will normally visit deep flowers and short-tonguedforagers shallow flowers, although extreme asymmetries in metaboliccosts may lead to the opposite arrangement. When deep and shallowflowers are randomly interspersed, nectarivores must decide,on encounter with a flower, whether to collect its nectar orcontinue searching. At low nectarivore densities, the optimalstrategy involves exploiting every encountered flower; however,as nectarivore densities increase and resources become scarce,long-tongued individuals should start concentrating on deepflowers and short-tongued individuals on shallow flowers. Therefore,regardless of the spatial distribution of flowers, corolla depthcan determine which nectarivore species exploit the nectar fromeach flower type in a given community. It follows that corollaelongation can evolve as a means to keep nectar thieves at bayif short-tongued visitors are less efficient pollinators thanlong-tongued visitors. 相似文献
150.
Sureda A Box A Enseñat M Alou E Tauler P Deudero S Pons A 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2006,144(2):191-196
Exposure of marine animals to certain toxic compounds can enhance reactive oxygen species production with subsequent damage to macromolecules and alterations in oxidant defenses levels. Caulerpenyne is the major metabolite synthesized by Caulerpa species, used as chemical defense affecting several cellular and molecular targets. We assessed the changes produced by the presence of Caulerpa spp. in the activities of antioxidant enzymes as well as lipid peroxidation levels in liver of the teleost Coris julis. Fish were captured at two stations with Caulerpa species-Caulerpa taxifolia and Caulerpa prolifera-and at a region with the seagrass Posidonia oceanica as negative control. Caulerpenyne concentration was significantly higher in C. prolifera than in C. taxifolia (p<0.05). Glutathione S-transferase, glutathione peroxidase and glutathione reductase activities were significantly higher in both Caulerpa stations compared to the P. oceanica (p<0.05). No statistical difference (p>0.05) existed in catalase activity between groups. Glutathione reductase activity is significantly higher in C. prolifera station than in C. taxifolia (p<0.05). Despite the variations in the antioxidant enzyme activities, there was no significant difference in malondialdehyde concentration. In conclusion, the production of caulerpenyne by Caulerpa species could induce an antioxidant adaptation in the liver of C. julis in order to prevent oxidative damage. 相似文献