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161.
Yaping Hao Jian Zhou Mi Zhou Xiaojing Ma Zhigang Lu Meifang Gao Xiaoping Pan Junling Tang Yuqian Bao Weiping Jia 《PloS one》2013,8(8)
Background
The fibroblast growth factor 19 (FGF19) has been implicated in recent studies as a potential regulator of glucose and lipid metabolism, which may lead to atherosclerosis. Here, we investigated the association of FGF19 with the presence and severity of coronary artery disease (CAD) in a Chinese population.Methods
A total of 315 patients with suspected or established CAD, including 205 males and 110 postmenopausal females, were enrolled and assessed by coronary angiography. CAD severity was determined by the Gensini score. Serum FGF19 was measured by quantitative sandwich ELISA.Results
FGF19 levels were not significantly different between male and female patients (median [interquartile range], 143.40 [87.96–250.80] vs. 141.60 [87.13–226.32] pg/mL, P = 0.773). CAD patients had lower levels of FGF19 than those without CAD (128.20 [80.62–226.58] vs. 188.00 [105.10–284.70] pg/mL, P = 0.007). FGF19 was negatively correlated with 2hPG (r = –0.150, P = 0.008), FINS (r = –0.169, P = 0.004), HOMA-IR (r = –0.171, P = 0.004), and the Gensini score (r = –0.141, P = 0.012), but positively correlated with HDL-c (r = 0.116, P = 0.041) and adiponectin (r = 0.128, P = 0.024). Moreover, FGF19 was found to be independently correlated with 2hPG (β = –0.146, P = 0.022) and adiponectin (β = 0.154, P = 0.016). After adjusting for other CAD risk factors, FGF19 was demonstrated to be an independent factor for Gensini score (β = –0.140, P = 0.019) and the presence of CAD (β = –1.248, P = 0.036).Conclusions
Serum FGF19 is associated with the presence and severity of CAD in a Chinese population. 相似文献162.
163.
Seung Mi Lee Jeong Woo Park Byoung Jae Kim Chan-Wook Park Joong Shin Park Jong Kwan Jun Bo Hyun Yoon 《PloS one》2013,8(12)
Background
The objective of this study was to determine whether acute histologic chorioamnionitis is associated with adverse neonatal outcomes in late preterm infants who were born after preterm PROM.Methodology/Principal Findings
The relationship between the presence of acute histologic chorioamnionitis and adverse neonatal outcome was examined in patients with preterm PROM who delivered singleton preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Nonparametric statistics were used for data analysis. The frequency of acute histologic chorioamnionitis was 24% in patients with preterm PROM who delivered preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Newborns born to mothers with histologic chorioamnionitis had significantly higher rates of adverse neonatal outcome (74% vs 51%; p<0.005) than those without histologic chorioamnionitis. This relationship remained significant after adjustment for gestational age at preterm PROM, gestational age at delivery, and exposure to antenatal corticosteroids.Conclusions/Significance
The presence of acute histologic chorioamnionitis is associated with adverse neonatal outcome in late preterm infants born to mothers with preterm PROM. 相似文献164.
Raeann Mettler H. Martin Schaefer Nikita Chernetsov Wolfgang Fiedler Keith A. Hobson Mihaela Ilieva Elisabeth Imhof Arild Johnsen Swen C. Renner Gregor Rolshausen David Serrano Tomasz Weso?owski Gernot Segelbacher 《PloS one》2013,8(11)
Migratory divides are thought to facilitate behavioral, ecological, and genetic divergence among populations with different migratory routes. However, it is currently contentious how much genetic divergence is needed to maintain distinct migratory behavior across migratory divides. Here we investigate patterns of neutral genetic differentiation among Blackcap (Sylvia atricapilla) populations with different migratory strategies across Europe. We compare the level of genetic divergence of populations migrating to southwestern (SW) or southeastern (SE) wintering areas with birds wintering in the British Isles following a recently established northwesterly (NW) migration route. The migratory divide between SW and SE wintering areas can be interpreted as a result of a re-colonization process after the last glaciation. Thus we predicted greater levels of genetic differentiation among the SW/SE populations. However, a lack of genetic differentiation was found between SW and SE populations, suggesting that interbreeding likely occurs among Blackcaps with different migratory orientations across a large area; therefore the SW/SE migratory divide can be seen as diffuse, broad band and is, at best, a weak isolating barrier. Conversely, weak, albeit significant genetic differentiation was evident between NW and SW migrants breeding sympatrically in southern Germany, suggesting a stronger isolating mechanism may be acting in this population. Populations located within/near the SW/SE contact zone were the least genetically divergent from NW migrants, confirming NW migrants likely originated from within the contact zone. Significant isolation-by-distance was found among eastern Blackcap populations (i.e. SE migrants), but not among western populations (i.e. NW and SW migrants), revealing different patterns of genetic divergence among Blackcap populations in Europe. We discuss possible explanations for the genetic structure of European Blackcaps and how gene flow influences the persistence of divergent migratory behaviors. 相似文献
165.
Mi Kyung Kwak Daniel T. Johnson Chunfang Zhu Suk Hyung Lee Ding-Wei Ye Richard Luong Zijie Sun 《PloS one》2013,8(1)
The PTEN tumor suppressor gene is frequently inactivated in human prostate cancer. Using Osr1 (odd skipped related 1)-Cre mice, we generated a novel conditional Pten knockout mouse strain, PtenLoxP:Osr1-Cre. Conditional biallelic and monoallelic Pten knockout mice were viable. Deletion of Pten expression was detected in the prostate of PtenLoxP/LoxP:Osr1-Cre mice as early as 2 weeks of age. Intriguingly, PtenLoxP/LoxP:Osr1-Cre mice develop high-grade prostatic intraepithelial neoplasms (PINs) with high penetrance as early as one-month of age, and locally invasive prostatic tumors after 12-months of age. PtenLoxP/+:Osr1-Cre mice show only mild oncogenic changes after 8-weeks of age. Castration of PtenLoxP/LoxP:Osr1-Cre mice shows no significant regression of prostate tumors, although a shift of androgen receptor (AR) staining from the nuclei to cytoplasm is observed in Pten null tumor cells of castrated mice. Enhanced Akt activity is observed in Pten null tumor cells of castrated PtenLoxP/LoxP:Osr1-Cre. This study provides a novel mouse model that can be used to investigate a primary role of Pten in initiating oncogenic transformation in the prostate and to examine other genetic and epigenetic changes that are required for tumor progression in the mouse prostate. 相似文献
166.
Jianjie Mi Alisa E. Shaw Chi W. Pak Keifer P. Walsh Laurie S. Minamide Barbara W. Bernstein Thomas B. Kuhn James R. Bamburg 《PloS one》2013,8(12)
Filament bundles (rods) of cofilin and actin (1:1) form in neurites of stressed neurons where they inhibit synaptic function. Live-cell imaging of rod formation is hampered by the fact that overexpression of a chimera of wild type cofilin with a fluorescent protein causes formation of spontaneous and persistent rods, which is exacerbated by the photostress of imaging. The study of rod induction in living cells calls for a rod reporter that does not cause spontaneous rods. From a study in which single cofilin surface residues were mutated, we identified a mutant, cofilinR21Q, which when fused with monomeric Red Fluorescent Protein (mRFP) and expressed several fold above endogenous cofilin, does not induce spontaneous rods even during the photostress of imaging. CofilinR21Q-mRFP only incorporates into rods when they form from endogenous proteins in stressed cells. In neurons, cofilinR21Q-mRFP reports on rods formed from endogenous cofilin and induced by all modes tested thus far. Rods have a half-life of 30–60 min upon removal of the inducer. Vesicle transport in neurites is arrested upon treatments that form rods and recovers as rods disappear. CofilinR21Q-mRFP is a genetically encoded rod reporter that is useful in live cell imaging studies of induced rod formation, including rod dynamics, and kinetics of rod elimination. 相似文献
167.
Sławomir J. Grabowski 《Journal of molecular modeling》2013,19(11):4713-4721
MP2(full)/6-311++G(3df,3pd) calculations were carried out on complexes linked through various non-covalent Lewis acid – Lewis base interactions. These are: hydrogen bond, dihydrogen bond, hydride bond and halogen bond. The quantum theory of ´atoms in molecules´ (QTAIM) as well as the natural bond orbitals (NBO) method were applied to analyze properties of these interactions. It was found that for the A-H…B hydrogen bond as well as for the A-X…B halogen bond (X designates halogen) the complex formation leads to the increase of s-character in the A-atom hybrid orbital aimed toward the H or X atom. In opposite, for the A…H-B hydride bond, where the H-atom possesses negative charge, the decrease of s-character in the B-atom orbital is observed. All these changes connected with the redistribution of the electron charge being the effect of the complex formation are in line with Bent´s rule. The numerous correlations between energetic, geometrical, NBO and QTAIM parameters were also found. Figure
QTAIM atomic radii for NH4 +…HMgH and Na+…HBeH 相似文献
168.
The structure of a two-dimensional film formed by adsorbed polymer chains was studied by means of Monte Carlo simulations. The polymer chains were represented by linear sequences of lattice beads and positions of these beads were restricted to vertices of a two-dimensional square lattice. Two different Monte Carlo methods were employed to determine the properties of the model system. The first was the random sequential adsorption (RSA) and the second one was based on Monte Carlo simulations with a Verdier-Stockmayer sampling algorithm. The methodology concerning the determination of the percolation thresholds for an infinite chain system was discussed. The influence of the chain length on both thresholds was presented and discussed. It was shown that the RSA method gave considerably lower thresholds for longer chains. This behavior can be explained by a different pool of chain conformations used in the calculations in both methods under consideration. Figure
The percolation cluster (in red) in the system consisting of long flexible chains 相似文献
169.
170.