Genetic variation in selected acorn and seedling characteristics of northern red oak (Quercus rubra L.).

Three separate studies were conducted to evaluate genetic variation in selected acorn and seedling characteristics of northern red oak (Quercus rubra L.) and white oak (Quercus alba L.). The objective of the studies were to: (1) evaluate sources of genetic variation and genotype-environmental interaction in seedling characteristics, (2) determine occurrence and frequency of polyembryony within and among half-sib families of northern red oak and relationships between acorn size and polyembryony, and (3) determine the maximum length of time northern red oak acorns can be left under simulated orchard conditions and collection procedures and remain viable. For the first objective, seedlings from 12 genetic families of both species were grown at locations in Tennessee and Georgia. White oak was found to be very sensitive to early growing season water stress that occurred at the Tennessee location, causing cessation of seedling growth following initial germination and growth. Following increased soil moisture levels, the seedlings generally failed and set a terminal bud to recommence growth and development. The northern red oak seedlings were subjected to the same water stress, but responded to the increase in soil moisture levels. However, the seedlings failed to reach the same size as the other location. Northern red oak families exhibited wide variation between family means. A distribution analysis on number of first-order lateral roots, indicated that most seedlings will fail to meet minimum standards for planting on highly competitive upland sites. Single tree and family heritability estimates for growth characteristics were relatively similar at both locations and generally lower than combined location estimates. Acorn germination and dissections were used to determine the occurrence of polyembryony in eight open-pollinated families of northern red oak. Relationships between acorn size and polyembryony was determined between collections of two mother trees. Only seed sources from Overton County, Tennessee, produced polyembryonic acorns. Acorn germination tests revealed more embryos per acorn than acorn dissections. As acorn size increased, the number of embryos increased in families predisposed to polyembryony. The occurrence of polyembryony in northern red oak open pollinated families indicated that seed sources should be screened for polyembryony occurrence. A two year study of the relationship between acorn moisture content, weather and the number of days following natural seed fall under simulated orchard conditions. Northern red oak acorns were collected from 10 trees and were subjected to five levels of shading for a thirty day period and at two day intervals, acorn moisture content was determined. It was found that acorn moisture content did not desiccate below 25 percent under all shading regimes, indicating that viability was not affected. Results of the experiment generally indicated that other factors such as predation should be of greater importance to overall viability of acorn crops than acorn desiccation

Interferences from blood collection tube components on clinical chemistry assays

Improper design or use of blood collection devices can adversely affect the accuracy of laboratory test results. Vascular access devices, such as catheters and needles, exert shear forces during blood flow, which creates a predisposition to cell lysis. Components from blood collection tubes, such as stoppers, lubricants, surfactants, and separator gels, can leach into specimens and/or adsorb analytes from a specimen; special tube additives may also alter analyte stability. Because of these interactions with blood specimens, blood collection devices are a potential source of pre-analytical error in laboratory testing. Accurate laboratory testing requires an understanding of the complex interactions between collection devices and blood specimens. Manufacturers, vendors, and clinical laboratorians must consider the pre-analytical challenges in laboratory testing. Although other authors have described the effects of endogenous substances on clinical assay results, the effects/impact of blood collection tube additives and components have not been well systematically described or explained. This review aims to identify and describe blood collection tube additives and their components and the strategies used to minimize their effects on clinical chemistry assays

Apolipoprotein Mimetic Peptides: A New Approach for the Treatment of Asthma

New treatments are needed for severe asthmatics to improve disease control and avoid severe toxicities associated with oral corticosteroids. We have used a murine model of house dust mite (HDM)-induced asthma to identify steroid-unresponsive genes that might represent targets for new therapeutic approaches for severe asthma. This strategy identified apolipoprotein E as a steroid-unresponsive gene with increased mRNA expression in the lungs of HDM-challenged mice. Furthermore, apolipoprotein E functioned as an endogenous negative regulator of airway hyperreactivity and goblet cell hyperplasia in experimental HDM-induced asthma. The ability of apolipoprotein E, which is expressed by lung macrophages, to attenuate AHR, and goblet cell hyperplasia is mediated by low density lipoprotein (LDL) receptors expressed by airway epithelial cells. Consistent with this, administration of an apolipoprotein E mimetic peptide, corresponding to amino acids 130–149 of the LDL receptor-binding domain of the holo-apoE protein, significantly reduced AHR and goblet cell hyperplasia in HDM-challenged apoE−/− mice. These findings identified the apolipoprotein E – LDL receptor pathway as a new druggable target for asthma that can be activated by administration of apoE-mimetic peptides. Similarly, apolipoprotein A-I may have therapeutic potential in asthma based upon its anti-inflammatory, anti-oxidative, and anti-fibrotic properties. Furthermore, administration of apolipoprotein A-I mimetic peptides has attenuated airway inflammation, airway remodeling, and airway hyperreactivity in murine models of experimental asthma. Thus, site-directed delivery of inhaled apolipoprotein E or apolipoprotein A-I mimetic peptides may represent novel treatment approaches that can be developed for asthma, including severe disease

Lipoprotein lipase regulates hematopoietic stem progenitor cell maintenance through DHA supply.

Lipoprotein lipase (LPL) mediates hydrolysis of triglycerides (TGs) to supply free fatty acids (FFAs) to tissues. Here, we show that LPL activity is also required for hematopoietic stem progenitor cell (HSPC) maintenance. Knockout of Lpl or its obligatory cofactor Apoc2 results in significantly reduced HSPC expansion during definitive hematopoiesis in zebrafish. A human APOC2 mimetic peptide or the human very low-density lipoprotein, which carries APOC2, rescues the phenotype in apoc2 but not in lpl mutant zebrafish. Creating parabiotic apoc2 and lpl mutant zebrafish rescues the hematopoietic defect in both. Docosahexaenoic acid (DHA) is identified as an important factor in HSPC expansion. FFA-DHA, but not TG-DHA, rescues the HSPC defects in apoc2 and lpl mutant zebrafish. Reduced blood cell counts are also observed in Apoc2 mutant mice at the time of weaning. These results indicate that LPL-mediated release of the essential fatty acid DHA regulates HSPC expansion and definitive hematopoiesis

High-density lipoprotein revisited: biological functions and clinical relevance

Previous interest in high-density lipoproteins (HDLs) focused on their possible protective role in atherosclerotic cardiovascular disease (ASCVD). Evidence from genetic studies and randomized trials, however, questioned that the inverse association of HDL-cholesterol (HDL-C) is causal. This review aims to provide an update on the role of HDL in health and disease, also beyond ASCVD. Through evolution from invertebrates, HDLs are the principal lipoproteins, while apolipoprotein B-containing lipoproteins first developed in vertebrates. HDLs transport cholesterol and other lipids between different cells like a reusable ferry, but serve many other functions including communication with cells and the inactivation of biohazards like bacterial lipopolysaccharides. These functions are exerted by entire HDL particles or distinct proteins or lipids carried by HDL rather than by its cholesterol cargo measured as HDL-C. Neither does HDL-C measurement reflect the efficiency of reverse cholesterol transport. Recent studies indicate that functional measures of HDL, notably cholesterol efflux capacity, numbers of HDL particles, or distinct HDL proteins are better predictors of ASCVD events than HDL-C. Low HDL-C levels are related observationally, but also genetically, to increased risks of infectious diseases, death during sepsis, diabetes mellitus, and chronic kidney disease. Additional, but only observational, data indicate associations of low HDL-C with various autoimmune diseases, and cancers, as well as all-cause mortality. Conversely, extremely high HDL-C levels are associated with an increased risk of age-related macular degeneration (also genetically), infectious disease, and all-cause mortality. HDL encompasses dynamic multimolecular and multifunctional lipoproteins that likely emerged during evolution to serve several physiological roles and prevent or heal pathologies beyond ASCVD. For any clinical exploitation of HDL, the indirect marker HDL-C must be replaced by direct biomarkers reflecting the causal role of HDL in the respective disease

Improving Understanding of Geometric Swimmer Locomotion

This work seeks to improve the knowledge surrounding geometric snake swimmers through both theoretical and practical means. To begin, manufacturing techniques for a silicon-based pneumatic actuator were validated through experimentation. When inflated, the actuators exhibited an unanticipated elongation. In an attempt to confirm theoretical displacement predictions, a more accurate dynamic model was created which included curvature-coupled extension. The resulting model was simulated with varying degrees of extension and corresponding optimized gaits. Results suggest that the pneumatic actuator’s efficiency does improve, although serpenoid systems used as a baseline comparison decreased in efficiency when extension was added. For the second stage of this work, it was assumed that a system’s theoretical model would be either completely unknown or unreasonable to calculate, thus another motion prediction method would be required. This method, referred to as Data-Driven or Empirical Local Connection Derivation, requires the system to execute a gait which adequately spans the desired shape space while its position and velocity are tracked through motion capture. This process is demonstrated using two different locomotors. Finally, these methods are integrated into a continually updated MATLAB extregistered{} graphical user interface (GUI) titled Geometric System Plotter. The aim of this software is to provide geometric system evaluation techniques without requiring background knowledge in geometric mechanics. In addition to the projects described here, other tools and general performance improvements have been integrated into the software for future releases

Determinants of HDL Cholesterol Efflux Capacity after Virgin Olive Oil Ingestion: Interrelationships with Fluidity of HDL Monolayer

Scope: Cholesterol efflux capacity of HDL (CEC) is inversely associated with cardiovascular risk. HDL composition, fluidity, oxidation, and size are related with CEC. We aimed to assess which HDL parameters were CEC determinants after virgin olive oil (VOO) ingestion. Methods and results: Post‐hoc analyses from the VOHF study, a crossover intervention with three types of VOO. We assessed the relationship of 3‐week changes in HDL‐related variables after intervention periods with independence of the type of VOO. After univariate analyses, mixed linear models were fitted with variables related with CEC and fluidity. Fluidity and Apolipoprotein (Apo)A‐I content in HDL was directly associated, and HDL oxidative status inversely, with CEC. A reduction in free cholesterol, an increase in triglycerides in HDL, and a decrease in small HDL particle number or an increase in HDL mean size, were associated to HDL fluidity. Conclusions: HDL fluidity, ApoA‐I concentration, and oxidative status are major determinants for CEC after VOO. The impact on CEC of changes in free cholesterol and triglycerides in HDL, and those of small HDL or HDL mean size, could be mechanistically linked through HDL fluidity. Our work points out novel therapeutic targets to improve HDL functionality in humans through nutritional or pharmacological interventions.Fil: Fernández Castillejo, Sara. Universitat Rovira I Virgili; EspañaFil: Rubió, Laura. Universitat Rovira I Virgili; España. Universidad de Lleida; EspañaFil: Hernáez, Álvaro. Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición; EspañaFil: Catalán, Úrsula. Universitat Rovira I Virgili; EspañaFil: Pedret, Anna. Universitat Rovira I Virgili; EspañaFil: Valls, Rosa M.. Universitat Rovira I Virgili; EspañaFil: Mosse, Juana Inés. Universidad de Lleida; España. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Covas, Maria Isabel. Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición; EspañaFil: Remaley, Alan T.. National Institutes of Health; Estados UnidosFil: Castañer, Olga. Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición; EspañaFil: Motilva, Maria José. Universidad de Lleida; EspañaFil: Solá, Rosa. Universitat Rovira I Virgili; Españ