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101.
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Parent‐of‐origin–dependent (epi)genetic factors are important determinants of prenatal development that program adult phenotype. However, data on magnitude and specificity of maternal and paternal genome effects on fetal bone are lacking. We used an outbred bovine model to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects on the fetal skeleton and analyzed phenotypic and molecular relationships between fetal muscle and bone. Analysis of 51 bone morphometric and weight parameters from 72 fetuses recovered at day 153 gestation (54% term) identified six principal components (PC1–6) that explained 80% of the variation in skeletal parameters. Parental genomes accounted for most of the variation in bone wet weight (PC1, 72.1%), limb ossification (PC2, 99.8%), flat bone size (PC4, 99.7%), and axial skeletal growth (PC5, 96.9%). Limb length showed lesser effects of parental genomes (PC3, 40.8%) and a significant nongenetic maternal effect (gestational weight gain, 29%). Fetal sex affected bone wet weight (PC1, p < 0.0001) and limb length (PC3, p < 0.05). Partitioning of variation explained by parental genomes revealed strong maternal genome effects on bone wet weight (74.1%, p < 0.0001) and axial skeletal growth (93.5%, p < 0.001), whereas paternal genome controlled limb ossification (95.1%, p < 0.0001). Histomorphometric data revealed strong maternal genome effects on growth plate height (98.6%, p < 0.0001) and trabecular thickness (85.5%, p < 0.0001) in distal femur. Parental genome effects on fetal bone were mirrored by maternal genome effects on fetal serum 25‐hydroxyvitamin D (96.9%, p < 0.001) and paternal genome effects on alkaline phosphatase (90.0%, p < 0.001) and their correlations with maternally controlled bone wet weight and paternally controlled limb ossification, respectively. Bone wet weight and flat bone size correlated positively with muscle weight (r = 0.84 and 0.77, p < 0.0001) and negatively with muscle H19 expression (r = –0.34 and –0.31, p < 0.01). Because imprinted maternally expressed H19 regulates growth factors by miRNA interference, this suggests muscle‐bone interaction via epigenetic factors. © 2014 American Society for Bone and Mineral Research.  相似文献   
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104.

Introduction

Left ventricular remodeling (LVR) is the most prognostically important consequence of acute myocardial infarction (AMI). The aim of the study was to assess the value of speckle tracking echocardiography in the prediction of left ventricular remodeling in patients after AMI and primary coronary angioplasty (PCI).

Material and methods

Eighty-eight patients (F/M = 31/57 patients; 63.6 ±11 years old) with coronary artery disease (CAD) and successful PCI were enrolled and divided into group I with ST-elevation myocardial infarction or non-ST elevation myocardial infarction and group II with stable angina pectoris. Conventional and speckle tracking echocardiography was performed 3 days (baseline), 30 days and 90 days after PCI. Patients were divided into 2 groups based on the presence of LVR (increase of LV end-diastolic and/or end-systolic volume > 20%) at 3 months follow-up.

Results

At initial presentation, 2-chamber longitudinal strain (9.4 ±3.5% vs. –11.6 ±3.6%, p < 0.04) and 4-chamber transverse strain (10.4 ±8.2% vs. 15.6 ±8%, p < 0.003) were lower in the LVR+ group compared to the LVR– group. LV wall motion score index did not differ between the two groups. After 30 days, circumferential apical and basal strain (–15.58 ±8.9% vs. –25.53 ±8.8%, p < 0.001; –15.02 ±5.6 vs. –19.78 ±6.3, p < 0.008), radial apical strain (9.96 ±8.4% vs. 14.15 ±5.5%, p < 0.03), 4-chamber longitudinal strain (–8.7 ±5.8% vs. –13.47 ±3.9%, p < 0.005), 4-chamber transverse strain (10.5 ±8.1% vs. 16.7 ±8.3%, p < 0.03), apical rotation (3.84 ±2.5° vs, 5.66 ±3.2°, p < 0.04) and torsion (6.15 ±4.1° vs. 8.98 ±4.6°, p < 0.03) were significantly decreased in the LVR+ group compared to the LVR– group. According to ROC analysis, circumferential apical strain > –15.92% (sensitivity 93%, specificity 59%, positive predictive value 90%) was the most powerful predictor of remodeling after primary PCI in AMI.

Conclusions

Our results suggest that impaired indices of LV deformation detected 3 days and 30 days after AMI may provide important predictive value in LV remodeling and patients’ follow-up.  相似文献   
105.
The engineering practices for applying the microbial precipitation of carbonates require a design of the blending biocement solution (BCS). The BCS is usually blended with concentrated strains NO-A10, reaction media, such as urea and CaCl2, and a solvent, i.e., water or seawater. To characterize the BCS, the unknown microbial characteristics, such as the cell viability, are complex factors. Therefore, the optical density (OD) was redefined as Rcv OD*, in which OD* was the tentative OD of the BCS used and Rcv was the conversion rate concerning the cell viability. To determine Rcv values, a standard precipitation curve based on the precipitation rate at 24 h was determined. It was found that the curve was expressed by λ1 OD+ λ2 OD2, in which λ1 and λ2 were 8.46 M and −17.633 M, respectively. With this, the Rcv and OD values of unknown BCS were estimated from the results of precipitation tests using arbitrary OD* values. By extending the testing time, the second order term of OD or OD* was negligible. Accordingly, the precipitation amount is expressed as 8.46 OD, in which the OD can be estimated by precipitation tests using arbitrary OD* values of BCSs. Unless the Ca2+ value is dominant, the optimum blending of BCS can be determined by OD. Thus, it is concluded that the blending design of BCS is achieved using 8.46 OD, or 8.46 Rcv OD*, and the standard precipitation curve was defined in this study.  相似文献   
106.
Our research focuses on phenomena accompanying adsorption of mesityl oxide (4-methylpent-3-en-2-one) on the surface of heterogeneous supported gold catalysts: Au/CeO2, Au/TiO2 and Au/SiO2. We have studied reduction in the gas phase of (volatile) α,β-unsaturated carbonyl compounds (R-(V)ABUCC) which mesityl oxide is a basic model of. In situ infrared (IR) spectroscopy was employed to establish that the most active catalysts allow adsorption of conjugated ketones or aldehydes in the enolate (i.e. bridge-like adsorption through the oxygen from the carbonyl group and the β-carbon) and carboxylic form or with the αC Created by potrace 1.16, written by Peter Selinger 2001-2019 βC double bond on a Lewis acidic site. Reductive properties of the catalysts and pure supports were studied by temperature-programmed reduction (TPR). We show that cerium(iv) oxide (CeO2, ceria) and titanium(iv) oxide (TiO2, titania) when decorated with gold nanoparticles (AuNP) can interact with hydrogen at temperatures approx. 150 °C lower than typical for pure oxides what includes even cyclic adsorption and instant release of H2 below 100 °C in the case of gold–ceria system. Morphology and structure characterisation by transmission electron microscopy (TEM) and powder X-ray diffraction (PXRD) confirms that, with the obtained Au loadings, we achieved excellent dispersion of AuNPs while maintaining their small size, preferably below 5 nm, even though the Au/CeO2 catalyst contained broad distribution of AuNPs sizes.

We deliver spectroscopic IR data describing the adsorption phenomena accompanying reduction of conjugated carbonyl compounds aided by heterogeneous catalysts.  相似文献   
107.
Torrefaction is one of the methods of thermal treatment of biomass, which allows obtaining a product of better quality in the form of biochar. The aim of the paper was to analyze the possibility of using goldenrod (Solidago canadensis, Solidago gigantea) for the production of biochar. The torrefaction process involved the vegetative and generative parts as well as the whole plant at temperatures of 250 °C and 275 °C, for 3 h. Next, the physicochemical properties of the raw material and biochar were determined, namely moisture content, ash content, volatile matter content, calorific value, and heat of combustion. The bulk density of raw biomass and biochar was also determined. It was found that after biomass torrefaction, the ash content, calorific value, and heat of combustion increased, while volatile matter content decreased. It has been observed that in both the case of raw biomass and biochar, the plant species and the sampled parts have a significant impact on the ash content, volatile matter content, calorific value, and heat of combustion.  相似文献   
108.
Non-thermal endovenous ablations, due to the lowest probability of complications, are the new method of treating chronic venous insufficiency—one of the most common diseases globally. The Flebogrif system (Balton Sp. z o.o., Warsaw, Poland) is a new mechano-chemical ablation system causing the mechanical damage of endothelium that allows for better sclerosant penetration into its wall. The purpose of the article is to provide mechanical characteristics in the form of force–displacement dependence for a single cutting element, and a bundle of cutting elements of Flebogrif as a whole for different levels of protrusion of the bundle of cutting elements. A TA.HD plus (Stable Micro Systems, Godalming, UK) analyzer equipped with special handles, was used for characteristics testing. The head movement speed used was 5 mm·s−1. The Flebogrif system was tested for three cutting element protrusion levels: L = Lmax, L = 0.9·Lmax, and L = 0.8·Lmax. Before testing, geometric measurement of the spacing of the cutting elements for three proposed protrusions was performed. It was established that decreasing the working length of the cutting elements will increase their rigidity, and, as a result, increase the force exerted on the internal surface of the vein wall. The obtained characteristics will allow for specifying contact force variability ranges and the corresponding diameter ranges of operated veins.  相似文献   
109.
So far, there are no results for research on the biomechanical parameters of giant miscanthus stalks taking into account both the influence of moisture content and the internode, from which the samples were taken. Therefore, the aim of the research was to comprehensively investigate the influence of the internode number (NrNod) and water content (MC) on the values of selected biomechanical parameters (modulus of elasticity and maximum stress) determined using various stress tests (three-point bending and compression along the fibers). The research was carried out for dry stalks of different humidities and for different internodes. The results obtained in this study proved that the independent variables of the water content and the internode number cause a statistically significant influence on the values of the examined biomechanical parameters of the miscanthus stem: the modulus of elasticity in compression, the maximum stress in compression, the modulus of elasticity in bending and the maximum stress in bending. The values of the modulus of elasticity (MOE) increase when increasing the NrNod. For individual internodes, MOE values are higher with a higher MC. The values of the maximum stress (σ) also increase when increasing the internode number. For individual internodes, the σ values are lower with a higher MC.  相似文献   
110.
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