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951.
Jorge Luis Olivares Graciela Inés Olivi Carina Verdasco Valeria Analia Ortiz Marcos Alejandro Mayer Juan Carlos Cresto 《Endocrinología y nutrición》2012,59(5):326-330
IntroductionIodine is considered to be an essential micronutrient in pregnant women. Iodine placental transport to the embryo-fetus is essential for hormone synthesis and is crucial for nervous system development. However, the relationship between iodine intake and placental weight and its potential implications for the newborn have not been studied.Material and methodsIodine intake was analyzed in 77 pregnant women based on urinary iodine excretion (UIE) levels, measured using Pinós modified method (normal value, ≥ 150 μg/L). Placental weight was measured (PW: normal, ≥500 g). In the newborn, weight, height, and head perimeter (HP) were also measured. Placental index (PI: placental weight/newborn weight) was calculated, and was considered normal if ≥0.15.ResultsUIE was normal in 50 pregnant women (mean ± SD, 279 μg/L ± 70.22 μg/L) and decreased in 27 (94 μg/L ± 31.49 μg/L). Newborns of mothers with low UIE had a similar weight (3357 g ± 416.30 g; n: 27) to those of mothers with normal UIE (3489 g ± 560.59 g; n: 50). Forty-four percent of mothers with low UIE had PW <500 g, and statistically lower HPs were found in newborns of mothers with low PW (PW3500 g: 36.05 cm ± 0.55 cm, n: 54; PW <500 g: 33.93 cm ± 15 cm, n:23, p < 0.019). Similar results were found with PI, but they did not reach statistical significance (0,17 ± 0,04; p = 0.066). No differences were seen in all other parameters.ConclusionThe study suggests the existence of a relationship between PW and HP. This finding may be related to iodine intake during pregnancy. 相似文献
952.
An understanding of why adenine (A) pairs with thymine (T) and cytosine (C) with guanine (G) in DNA is very useful in the
design of sensors and other related devices. We report the use of dissociation energies, geometries and molecular electrostatic
potentials (MEPs) to justify the canonical (AT and CG) Watson-Crick pairs. We also analyze all mismatches in both configurations—cis
and trans—with respect to their glycoside bonds. As expected, we found that the most stable pair configuration corresponds
to CG, providing an energy criterion for that preferred configuration. The reason why A gets together with T is much more
difficult to explain as the energy of this pair is smaller than the energy of some other mismatched pairs. We tested MEPs
to see if they could shed light on this problem. Interestingly, MEPs yield a unique pattern (shape) for the two canonical
cases but different shapes for the mismatches. A tunnel of positive potential surrounded by a negative one is found interconnecting
the three H-bonds of CG and the two of AT. This MEP tunnel, assisted partially by energetics and geometrical criteria, unambiguously
determine a distinctive feature of the affinity between A and T as well as that between G and C. 相似文献
953.
Bermúdez-Lugo JA Perez-Gonzalez O Rosales-Hernández MC Ilizaliturri-Flores I Trujillo-Ferrara J Correa-Basurto J 《Journal of molecular modeling》2012,18(6):2301-2310
Epigenetic therapy is an important focus of research for drug development in the treatment of cancer. Valproic acid (VPA) is an HDAC inhibitor that has been evaluated in clinical studies. Despite its success in treating cancer, the mechanism of inhibition of VPA in HDAC is unknown. To this end, we have used docking and molecular dynamic simulations to investigate VPA binding to HDAC, employing both native and rebuilt 3-D structures. The results showed that VPA, via its carboxyl group, coordinates the Zn atom and other local residues (H141-142 and Y360) located at the catalytic site (CS) of HDAC. This causes electrostatic and hydrogen bonding interactions while having little interaction with the hydrophobic side chains, resulting in a low affinity. However, after several docking studies on different native HDAC 3-D structures and after using several snapshots from MD simulations, it became apparent that VPA bound with highest affinity at a site located at the acetyl-releasing channel, termed the hydrophobic active site channel (HASC). The affinity of VPA for HASC was due to its highly hydrophobic properties that allow VPA to take part in van der Waals interactions with Y18, I19, Y20, V25, R37, A38, V41, H42, I135 and W137, while VPA's carboxylate group has several hydrogen bonding interactions with the backbones of S138, I19, N136 and W137. MD simulations showed that the HASC door continuously opened and closed, which affected the affinity of VPA to the HASC, but the affinity toward the HASC was consistently higher than that obtained for the CS, suggesting that the HASC could be involved in the mechanism of inhibition. 相似文献
954.
Electronic properties of Fe(2-10) clusters and their ions are described by an all-electron ab initio density functional theory computational analysis using the Handy's OPTX exchange and the gradient-corrected correlation functional of Perdew, Burke and Ernzerhof with a triple-zeta valence basis set plus polarization functions. Ground state structures, magnetic moments, dissociation energies, binding energies, IR vibrational spectra, vertical and adiabatic ionization energies, and electron affinities are reported. Two possible states for Fe(2) which are separated by 81.54 meV are described as possible Fe(2), while the septet (ground state) yields an accurate bond distance (error of 0.02??); the nonet yields a precise vibrational frequency (error of 10.1?cm(-1)). Fe(2) binding energy (0.05 eV/atom error) more closely resembles experimental data than any other previously reported computational methods. In addition, the Fe(6) is found to be the most stable cluster within our set being analyzed. 相似文献
955.
956.
Graciela Piñeiro Jorge Ferigolo Alejandro Ramos Michel Laurin 《Comptes Rendus Palevol》2012,11(5):379-391
The Early Permian mesosaurids are the oldest known aquatic amniotes with an exclusively Gondwanan distribution. Although several hundred of complete skeletons have been discovered and intensively studied, the anatomy and taxonomic composition of the group, as well as its phylogenetic relationships remain controversial. Several well-preserved mesosaurid specimens found in Uruguay justify a new anatomical reconstruction of the skull of Mesosaurus tenuidens, differing from earlier ones especially in the presence of a lower temporal fenestra. The significance of this structure for the evolution of temporal fenestration in amniotes is evaluated according to the two most recent phylogenetic hypotheses, in which mesosaurids are basalmost sauropsids or basalmost parareptiles. A synapsid-like fenestration may be the primitive condition for Amniota, and it may be also a basal condition for parareptiles, because recent phylogenies suggest a basal position for mesosaurids and lanthanosuchoids within that group, and both possess a lower temporal fenestra. Our results also give a moderately strengthened support for diapsid affinities of turtles. 相似文献
957.
Dastani Z Hivert MF Timpson N Perry JR Yuan X Scott RA Henneman P Heid IM Kizer JR Lyytikäinen LP Fuchsberger C Tanaka T Morris AP Small K Isaacs A Beekman M Coassin S Lohman K Qi L Kanoni S Pankow JS Uh HW Wu Y Bidulescu A Rasmussen-Torvik LJ Greenwood CM Ladouceur M Grimsby J Manning AK Liu CT Kooner J Mooser VE Vollenweider P Kapur KA Chambers J Wareham NJ Langenberg C Frants R Willems-Vandijk K Oostra BA Willems SM Lamina C Winkler TW Psaty BM Tracy RP Brody J Chen I Viikari J Kähönen M 《PLoS genetics》2012,8(3):e1002607
Circulating levels of adiponectin, a hormone produced predominantly by adipocytes, are highly heritable and are inversely associated with type 2 diabetes mellitus (T2D) and other metabolic traits. We conducted a meta-analysis of genome-wide association studies in 39,883 individuals of European ancestry to identify genes associated with metabolic disease. We identified 8 novel loci associated with adiponectin levels and confirmed 2 previously reported loci (P = 4.5×10−8–1.2×10−43). Using a novel method to combine data across ethnicities (N = 4,232 African Americans, N = 1,776 Asians, and N = 29,347 Europeans), we identified two additional novel loci. Expression analyses of 436 human adipocyte samples revealed that mRNA levels of 18 genes at candidate regions were associated with adiponectin concentrations after accounting for multiple testing (p<3×10−4). We next developed a multi-SNP genotypic risk score to test the association of adiponectin decreasing risk alleles on metabolic traits and diseases using consortia-level meta-analytic data. This risk score was associated with increased risk of T2D (p = 4.3×10−3, n = 22,044), increased triglycerides (p = 2.6×10−14, n = 93,440), increased waist-to-hip ratio (p = 1.8×10−5, n = 77,167), increased glucose two hours post oral glucose tolerance testing (p = 4.4×10−3, n = 15,234), increased fasting insulin (p = 0.015, n = 48,238), but with lower in HDL-cholesterol concentrations (p = 4.5×10−13, n = 96,748) and decreased BMI (p = 1.4×10−4, n = 121,335). These findings identify novel genetic determinants of adiponectin levels, which, taken together, influence risk of T2D and markers of insulin resistance. 相似文献
958.
Yashbir Dewan Edward O Komolafe Jorge H Mejía-Mantilla Pablo Perel Ian Roberts Haleema Shakur 《Trials》2012,13(1):1-14
Background
Single-limb knee extension exercises have been found to be effective at improving lower extremity exercise capacity in patients with chronic obstructive pulmonary disease (COPD). Since the positive local physiological effects of exercise training only occur in the engaged muscle(s), should upper extremity muscles also be included to determine the effect of single limb exercises in COPD patients.Methods/design
Trial design: a prospective, assessor-blind, block randomized controlled, parallel-group multicenter trial. Participants: stage II-IV COPD patients, > 40?years of age, ex-smokers, with stable medical treatment will be included starting May 2011. Recruitment at three locations in Sweden. Interventions: 1) high-repetitive single limb exercise (HRSLE) training with elastic bands, 60 minutes, three times/week for 8?weeks combined with four sessions of 60 minutes patient education, or 2) the same patient education alone. Outcomes: Primary: determine the effects of HRSLE on local muscle endurance capacity (measured as meters walked during 6-minute walk test and rings moved on 6-minute ring and pegboard test) and quality of life (measured as change on the Swedish version of the Chronic Respiratory Disease Questionnaire). Secondary: effects on maximal strength, muscular endurance, dyspnea, self-efficacy, anxiety and depression. The relationship between changes in health-related variables and changes in exercise capacity, sex-related differences in training effects, feasibility of the program, strategies to determine adequate starting resistance and provide accurate resistance for each involved movement and the relationship between muscle fatigue and dyspnea in the different exercise tests will also be analyzed. Randomization: performed by a person independent of the recruitment process and using a computer random number generator. Stratification by center and gender with a 1:1 allocation to the intervention or control using random block sizes. Blinding: all outcome assessors will be blinded to group assignment.Discussion
The results of this project will contribute to increase the body of knowledge regarding COPD and HRSLE.Trial registration
ClinicalTrials.gov Identifier: NCT01354067. Registration date: 2011-05-11. First participant randomized: 2011-09-02 相似文献959.
M Armayones MA Vilaseca J Cutillas J Fàbrega JJ Fernández M García N Egea M Pousada B Gómez-Zuñiga J Pérez-Payarols R Artuch F Palau M Serrano 《Orphanet journal of rare diseases》2012,7(1):53
ABSTRACT: Web-based interventions are effective on the patient empowerment. Guiametabolica.org constitutes an interface for people involved in inherited metabolic diseases, trying to facilitate access to information and contact with professionals and other patients, offering a platform to develop support groups. Guiametabolica.org is widely considered for Spanish-speaking patients and caregivers with inherited metabolic diseases. Preliminary evaluations show changes in their habits, decrease in their senses of isolation and improvement regarding self-efficacy. Specific inherited metabolic diseases websites, especially participative websites, should be considered as a complement to more traditional clinical approaches. Their contribution lies in patient's general well-being, without interfering with traditional care. 相似文献
960.
Elda?I?Espa?a-Gamboa Javier?O?Mijangos-Cortés Galdy?Hernández-Zárate Jorge?A?Domínguez?Maldonado Liliana?M?Alzate-GaviriaEmail author 《Biotechnology for biofuels》2012,5(1):82