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121.
Maria Alícia Carrillo-Sepúlveda Graziela S. Ceravolo Cristina R. Furstenau Priscilla de Souza Monteiro Zuleica Bruno-Fortes Maria Helena Carvalho Francisco R. Laurindo Rita C. Tostes R. Clinton Webb Maria Luiza M. Barreto-Chaves 《PloS one》2013,8(4)
Hyperthyroidism is characterized by increased vascular relaxation and decreased vascular contraction and is associated with augmented levels of triiodothyronine (T3) that contribute to the diminished systemic vascular resistance found in this condition. T3 leads to augmented NO production via PI3K/Akt signaling pathway, which in turn causes vascular smooth muscle cell (VSMC) relaxation; however, the underlying mechanisms involved remain largely unknown. Evidence from human and animal studies demonstrates that the renin-angiotensin system (RAS) plays a crucial role in vascular function and also mediates some of cardiovascular effects found during hyperthyroidism. Thus, in this study, we hypothesized that type 2 angiotensin II receptor (AT2R), a key component of RAS vasodilatory actions, mediates T3 induced-decreased vascular contraction. Marked induction of AT2R expression was observed in aortas from T3-induced hyperthyroid rats (Hyper). These vessels showed decreased protein levels of the contractile apparatus: α-actin, calponin and phosphorylated myosin light chain (p-MLC). Vascular reactivity studies showed that denuded aortic rings from Hyper rats exhibited decreased maximal contractile response to angiotensin II (AngII), which was attenuated in aortic rings pre-incubated with an AT2R blocker. Further study showed that cultured VSMC stimulated with T3 (0.1 µmol/L) for 24 hours had increased AT2R gene and protein expression. Augmented NO levels and decreased p-MLC levels were found in VSMC stimulated with T3, both of which were reversed by a PI3K/Akt inhibitor and AT2R blocker. These findings indicate for the first time that the AT2R/Akt/NO pathway contributes to decreased contractile responses in rat aorta, promoted by T3, and this mechanism is independent from the endothelium. 相似文献
122.
123.
Estimating date of infection for HIV-1-infected patients is vital for disease tracking and informed public health decisions, but is difficult to obtain because most patients have an established infection of unknown duration at diagnosis. Previous studies have used HIV-1-specific immunoglobulin G (IgG) levels as measured by the IgG capture BED enzyme immunoassay (BED assay) to indicate if a patient was infected recently, but a time-continuous model has not been available. Therefore, we developed a logistic model of IgG production over time. We used previously published metadata from 792 patients for whom the HIV-1-specific IgG levels had been longitudinally measured using the BED assay. To account for patient variability, we used mixed effects modeling to estimate general population parameters. The typical patient IgG production rate was estimated at r = 6.72[approximate 95% CI 6.17,7.33]×10−3 OD-n units day−1, and the carrying capacity at K = 1.84[1.75,1.95] OD-n units, predicting how recently patients seroconverted in the interval ∧
t = (31,711) days. Final model selection and validation was performed on new BED data from a population of 819 Swedish HIV-1 patients diagnosed in 2002–2010. On an appropriate subset of 350 patients, the best model parameterization had an accuracy of 94% finding a realistic seroconversion date. We found that seroconversion on average is at the midpoint between last negative and first positive HIV-1 test for patients diagnosed in prospective/cohort studies such as those included in the training dataset. In contrast, seroconversion is strongly skewed towards the first positive sample for patients identified by regular public health diagnostic testing as illustrated in the validation dataset. Our model opens the door to more accurate estimates of date of infection for HIV-1 patients, which may facilitate a better understanding of HIV-1 epidemiology on a population level and individualized prevention, such as guidance during contact tracing. 相似文献
124.
Filumena Maria Gomes S. V. Subramanian Ana Maria de Ulh?a Escobar Maria Helena Valente Sandra Josefina Ferraz Ellero Grisi Alexandra Brentani Günther Fink 《PloS one》2013,8(6)
Background
A growing literature suggests that low birth weight increases the risk of poor health outcomes in adulthood. We tested this hypothesis among young adults living in São Paulo State, Brazil.Methods and Findings
To identify the effects of low birth weight on young adulthood outcomes, a medical assessment of 297 individuals born between 1977 and 1989 was conducted at a primary care unit in São Paulo State, Brazil. We analyzed body mass index (BMI), waist-hip ratio, blood pressure, fasting glucose and total cholesterol levels using linear and logistic regressions. Low birth was negatively associated with BMI (β = −2.0, 95% CI: −3.69, −0.27, p = 0.02), fasting glucose levels (β = −1.9, 95% CI: −3.9, −0.07, p = 0.05), waist-hip ratio (β = −0.03, 95% CI: −0.07, −0.01, p = 0.10), systolic blood pressure (β = −3.32, 95% CI: −7.60, 0.96, p = 0.12), and total cholesterol levels (β = −3.19, 95% CI: −16.43, 10.05, p = 0.636). Low birth weight was also associated with lower odds of young adults being overweight and obese, but neither association was statistically significant. Weight gain in the first 12 months of life was associated with higher adult BMI (β = 0.79, 95% CI: −0.0455, 1.623, p = 0.064) and blood pressure (β = 2.79, 95% CI: 0.22, 5.35, p = 0.034). No associations were found between low birth weight and early life (catch-up) growth.Conclusions
Low birth weight was not associated with poor health outcomes among young adults in Brazil. These results appear inconsistent with the original Barker hypothesis, but will need to be corroborated in larger samples with longer follow-ups to allow a more general evaluation of the validity of the hypothesis in low and middle income countries. 相似文献125.
Xabier Urra Helena Ari?o Laura Llull Sergio Amaro Víctor Obach álvaro Cervera ángel Chamorro 《PloS one》2013,8(3)
Introduction
In up to one third of patients with mild stroke suitable to receive systemic thrombolysis the treatment is not administered because the treating physicians estimate a good spontaneous recovery. However, it is not settled whether the fate of these patients is equivalent to those who are thrombolysed.Methods
We analyzed 203 consecutive patients (134 men and 69 women, mean age 69±14 years) without premorbid disability and a NIHSS score ≤5 at admission [median 3 (IQR 2–4)]. Intravenous thrombolysis was administered within 4.5 hours from stroke onset (n = 119), or it was withheld (n = 84) whenever the treating physician predicted a spontaneous recovery. The baseline risk factors, clinical course, infarction volume, bleeding complications, and functional outcome at 3 months were analyzed and declared to a Web-based registry which was accessible to the local Health Authorities.Results
Expectedly, not thrombolysed patients had the mildest strokes at admission [median 2 (IQR 1–3.75)]. At day 2 to 5, the infarct volume on DWI-MRI was similar in both groups. There were no symptomatic cerebral bleedings in the study. An ordinal regression model adjusted for baseline stroke severity showed that thrombolysis was associated with a greater proportion of patients who shifted down on the modified Rankin Scale score at 3 months (OR 2.66; 95% CI 1.49–4.74, p = 0.001).Conclusions
Intravenous thrombolysis seems to be safe in patients with mild stroke and may be associated with improved outcome compared with untreated patients. These results support the evaluation of the efficacy of intravenous thrombolysis in mild stroke patients in randomized clinical trials. 相似文献126.
Kevin Kurt Jean-Philippe Rasigade Frederic Laurent Richard V. Goering Helena ?emli?ková Ivana Machova Marc J. Struelens Andreas E. Zautner Silva Holtfreter Barbara Br?ker Stephen Ritchie Sin Reaksmey Direk Limmathurotsakul Sharon J. Peacock Christiane Cuny Franziska Layer Wolfgang Witte Ulrich Nübel 《PloS one》2013,8(3)
We investigated the population structure of Staphylococcus aureus clonal complex CC121 by mutation discovery at 115 genetic housekeeping loci from each of 154 isolates, sampled on five continents between 1953 and 2009. In addition, we pyro-sequenced the genomes from ten representative isolates. The genome-wide SNPs that were ascertained revealed the evolutionary history of CC121, indicating at least six major clades (A to F) within the clonal complex and dating its most recent common ancestor to the pre-antibiotic era. The toxin gene complement of CC121 isolates was correlated with their SNP-based phylogeny. Moreover, we found a highly significant association of clinical phenotypes with phylogenetic affiliations, which is unusual for S. aureus. All isolates evidently sampled from superficial infections (including staphylococcal scalded skin syndrome, bullous impetigo, exfoliative dermatitis, conjunctivitis) clustered in clade F, which included the European epidemic fusidic-acid resistant impetigo clone (EEFIC). In comparison, isolates from deep-seated infections (abscess, furuncle, pyomyositis, necrotizing pneumonia) were disseminated in several clades, but not in clade F. Our results demonstrate that phylogenetic lineages with distinct clinical properties exist within an S. aureus clonal complex, and that SNPs serve as powerful discriminatory markers, able to identify these lineages. All CC121 genomes harboured a 41-kilobase prophage that was dissimilar to S. aureus phages sequenced previously. Community-associated MRSA and MSSA from Cambodia were extremely closely related, suggesting this MRSA arose in the region. 相似文献
127.
Elena Bellou Maria Maraki Faidon Magkos Helena Botonaki Demosthenes B. Panagiotakos Stavros A. Kavouras Labros S. Sidossis 《PloS one》2013,8(3)
Background
Acute reduction in dietary energy intake reduces very low-density lipoprotein triglyceride (VLDL-TG) concentration. Although chronic dietary energy surplus and obesity are associated with hypertriglyceridemia, the effect of acute overfeeding on VLDL-TG metabolism is not known.Objective
The aim of the present study was to investigate the effects of acute negative and positive energy balance on VLDL-TG metabolism in healthy women.Design
Ten healthy women (age: 22.0±2.9 years, BMI: 21.2±1.3 kg/m2) underwent a stable isotopically labeled tracer infusion study to determine basal VLDL-TG kinetics after performing, in random order, three experimental trials on the previous day: i) isocaloric feeding (control) ii) hypocaloric feeding with a dietary energy restriction of 2.89±0.42 MJ and iii) hypercaloric feeding with a dietary energy surplus of 2.91±0.32 MJ. The three diets had the same macronutrient composition.Results
Fasting plasma VLDL-TG concentrations decreased by ∼26% after hypocaloric feeding relative to the control trial (P = 0.037), owing to decreased hepatic VLDL-TG secretion rate (by 21%, P = 0.023) and increased VLDL-TG plasma clearance rate (by ∼12%, P = 0.016). Hypercaloric feeding increased plasma glucose concentration (P = 0.042) but had no effect on VLDL-TG concentration and kinetics compared to the control trial.Conclusion
Acute dietary energy deficit (∼3MJ) leads to hypotriglyceridemia via a combination of decreased hepatic VLDL-TG secretion and increased VLDL-TG clearance. On the other hand, acute dietary energy surplus (∼3MJ) does not affect basal VLDL-TG metabolism but disrupts glucose homeostasis in healthy women. 相似文献128.
Marcelo Magioli Katia Maria Paschoaletto Micchi de Barros Ferraz Eleonore Zulnara Freire Setz Alexandre Reis Percequillo Michelle Viviane de Sá Santos Rondon Vanessa Villanova Kuhnen Mariana Cristina da Silva Canhoto Karen Evelyn Almeida dos Santos Claudia Zukeran Kanda Gabriela de Lima Fregonezi Helena Alves do Prado Mitra Katherina Ferreira Milton Cezar Ribeiro Priscilla Marqui Schmidt Villela Luiz Lehmann Coutinho Márcia Gonçalves Rodrigues 《European Journal of Wildlife Research》2016,62(4):431-446
129.
Acardiac twin pregnancies part II: Fetal risk of chorangioma and sacrococcygeal teratoma predicted by pump/acardiac umbilical vein diameters 下载免费PDF全文
130.
Alexander Nagy Lenka ?erníková Eli?ka Vitásková Vlastimil K?ivda ádám Dán Zuzana Dirbáková Helena Ji?incová Bohumír Procházka Kamil Sedlák Martina Havlí?ková 《PloS one》2016,11(3)
In the present work, we optimised and evaluated a qPCR system integrating 6-FAM (6-carboxyfluorescein)-labelled TaqMan probes and melting analysis using the SYTO 82 (S82) DNA binding dye in a single reaction. We investigated the influence of the S82 on various TaqMan and melting analysis parameters and defined its optimal concentration. In the next step, the method was evaluated in 36 different TaqMan assays with a total of 729 paired reactions using various DNA and RNA templates, including field specimens. In addition, the melting profiles of interest were correlated with the electrophoretic patterns. We proved that the S82 is fully compatible with the FAM-TaqMan system. Further, the advantages of this approach in routine diagnostic TaqMan qPCR were illustrated with practical examples. These included solving problems with flat or other atypical amplification curves or even false negativity as a result of probe binding failure. Our data clearly show that the integration of the TaqMan qPCR and melting analysis into a single assay provides an additional control option as well as the opportunity to perform more complex analyses, get more data from the reactions, and obtain analysis results with higher confidence. 相似文献