Myocardial dysfunction in the periinfarct and remote regions following anterior infarction in rats quantified by 2D radial strain echocardiography: An observational cohort study

<p>Abstract</p> <p>Background</p> <p>Heart failure from adverse ventricular remodeling follows myocardial infarction, but the contribution of periinfarct and remote myocardium to the development of cardiomyopathy remains poorly defined. 2D strain echocardiography (2DSE) is a novel and sensitive tool to measure regional myocardial mechanics. The aim is to quantify radial strain in infarcted (I), periinfarct (PI) and remote (R) myocardial regions acutely and chronically following anterior infarction in rats.</p> <p>Methods</p> <p>The left anterior coronary artery of male Sprague-Dawley rats (270–370 g) were occluded for 20–30 minutes and 2DSE was performed in the acute setting (n = 10; baseline and 60 minutes post-reperfusion) and in the chronic setting (n = 14; baseline, 1, 3 and 6 weeks). Using software, radial strain was measured in the mid-ventricle in short axis view. The ventricle was divided into 3 regions: I (anteroseptum, anterior and anterolateral), PI – (inferoseptum and inferolateral) and R – (inferior). Infarct size was measured using triphenyl tetrazolium chloride in the acute group.</p> <p>Results</p> <p>Following infarct, adverse remodeling occurred with progressive increase in left ventricular size, mass and reduced fractional shortening within 6 weeks. Radial strain decreased not only in the infarct but also in the periinfarct and remote regions acutely and chronically (I, PI, R, change vs. baseline, 60 minutes -32.7 ± 8.7, -17.4 ± 9.4, -13.5 ± 11.6%; 6 weeks -24.4 ± 8.2, -17.7 ± 8.3, -15.2 ± 8.4% respectively, all p < 0.05). Reduced radial strain in periinfarct and remote regions occurred despite minimal or absent necrosis (area of necrosis I, PI, R: 48.8 ± 23, 5.1 ± 6.6, 0 ± 0%, p < 0.001 vs. I).</p> <p>Conclusion</p> <p>Following left anterior coronary occlusion, radial strain decreased at 60 minutes and up to 6 weeks in the periinfarct and remote regions, similar to the reduction in the infarct region. This demonstrates early and chronic myopathic process in periinfarct and remote regions following myocardial infarction that may be an under recognized but important contributor to adverse left ventricular remodeling and progression to ischemic cardiomyopathy.</p

Characterization of barley (Hordeum vulgare L.) NAC transcription factors suggests conserved functions compared to both monocots and dicots

<p>Abstract</p> <p>Background</p> <p>The NAC transcription factor family is involved in the regulation of traits in both monocots and dicots of high agronomic importance. Understanding the precise functions of the NAC genes can be of utmost importance for the improvement of cereal crop plants through plant breeding. For the cereal crop plant barley (<it>Hordeum vulgare </it>L.) only a few <it>NAC </it>genes have so far been investigated.</p> <p>Results</p> <p>Through searches in publicly available barley sequence databases we have obtained a list of 48 barley <it>NAC </it>genes (<it>HvNACs</it>) with 43 of them representing full-length coding sequences. Phylogenetic comparisons to Brachypodium, rice, and Arabidopsis NAC proteins indicate that the barley NAC family includes members from all of the eight NAC subfamilies, although by comparison to these species a number of <it>HvNACs </it>still remains to be identified. Using qRT-PCR we investigated the expression profiles of 46 <it>HvNACs </it>across eight barley tissues (young flag leaf, senescing flag leaf, young ear, old ear, milk grain, late dough grain, roots, and developing stem) and two hormone treatments (abscisic acid and methyl jasmonate).</p> <p>Conclusions</p> <p>Comparisons of expression profiles of selected barley <it>NAC </it>genes with the published functions of closely related <it>NAC </it>genes from other plant species, including both monocots and dicots, suggest conserved functions in the areas of secondary cell wall biosynthesis, leaf senescence, root development, seed development, and hormone regulated stress responses.</p

A meta-analysis of long-term effects of conservation agriculture on maize grain yield under rain-fed conditions

Conservation agriculture involves reduced tillage, permanent soil cover and crop rotations to enhance soil fertility and to supply food from a dwindling land resource. Recently, conservation agriculture has been promoted in Southern Africa, mainly for maize-based farming systems. However, maize yields under rain-fed conditions are often variable. There is therefore a need to identify factors that influence crop yield under conservation agriculture and rain-fed conditions. Here, we studied maize grain yield data from experiments lasting 5 years and more under rain-fed conditions. We assessed the effect of long-term tillage and residue retention on maize grain yield under contrasting soil textures, nitrogen input and climate. Yield variability was measured by stability analysis. Our results show an increase in maize yield over time with conservation agriculture practices that include rotation and high input use in low rainfall areas. But we observed no difference in system stability under those conditions. We observed a strong relationship between maize grain yield and annual rainfall. Our meta-analysis gave the following findings: (1) 92% of the data show that mulch cover in high rainfall areas leads to lower yields due to waterlogging; (2) 85% of data show that soil texture is important in the temporal development of conservation agriculture effects, improved yields are likely on well-drained soils; (3) 73% of the data show that conservation agriculture practices require high inputs especially N for improved yield; (4) 63% of data show that increased yields are obtained with rotation but calculations often do not include the variations in rainfall within and between seasons; (5) 56% of the data show that reduced tillage with no mulch cover leads to lower yields in semi-arid areas; and (6) when adequate fertiliser is available, rainfall is the most important determinant of yield in southern Africa. It is clear from our results that conservation agriculture needs to be targeted and adapted to specific biophysical conditions for improved impact

A novel COMP mutation in a pseudoachondroplasia family of Chinese origin

<p>Abstract</p> <p>Background</p> <p>Pseudoachondroplasia (PSACH) is caused exclusively by mutations in the gene for cartilage oligomeric matrix protein (<it>COMP</it>). Only a small number of studies have documented the clinical phenotype and genetic basis in Chinese PSACH patients.</p> <p>Case presentation</p> <p>We investigated a four-generation PSACH pedigree of Chinese Han origin. Two patients and two unaffected individuals were recruited for clinical evaluation and molecular genetic analysis. The genomic DNA was extracted from peripheral blood leukocytes. Polymerase chain reaction (PCR) was adopted to amplify the 8-19 exons of <it>COMP </it>gene. Then the products were sequenced bi-directionally for screening mutation. Clinical evaluation revealed that PSACH patients in this pedigree had a severe disproportionate short stature (-10SD). A heterozygous TGTCCCTGG insertion in exon 13, between nucleotide 1352T and 1353G, were identified in the patients except the unaffected individuals, which resulted in a three-amino-acid insertion (451V_452P ins VPG) in the sixth calmodulin-like repeat of the <it>COMP </it>protein.</p> <p>Conclusion</p> <p>This c. 1352_1353ins TGTCCCTGG is a novel mutation responsible for severe familial PSACH.</p

Evaluation of porcine epidemic diarrhea virus transmission and the immune response in growing pigs

Citation: Crawford, K., Lager, K., Miller, L., Opriessnig, T., Gerber, P., & Hesse, R. (2015). Evaluation of porcine epidemic diarrhea virus transmission and the immune response in growing pigs. Veterinary Research, 46, 9. doi:10.1186/s13567-015-0180-5Clinical disease associated with porcine epidemic diarrhea virus (PEDV) infection in naive pigs is well chronicled; however, information on endemic PEDV infection is limited. To characterize chronic PEDV infection, the duration of infectious virus shedding and development of protective immunity was determined. On Day 0 (D0), a growing pig was challenged with PEDV and 13 contacts were commingled. On D7, 9 contact pigs (principal virus group (PG)), were selected, moved to a separate room and commingled with one sentinel pig (S1). This process was repeated weekly with S2, S3 and S4. The PG was PEDV-positive by PCR from D3-11, with some pigs intermittently positive to D42. Pigs S1 and S2 were PEDV-positive within 24 hours of commingling. Antibodies were detected in all PG by D21 and by 7 days post-contact in S1 and S2. Pigs S3 and S4 were PCR and antibody negative following commingling. To evaluate protective immunity, 5 naive pigs (N) and the PG were challenged (N/C, PG/C) with homologous virus on D49. All N/C pigs were PEDV PCR-positive by D52 with detection out to D62 in 3/5 N/C pigs. All PG/C pigs were PEDV PCR-negative post-challenge. By D63, all N/C seroconverted. Although PEDV RNA was demonstrated in pigs after primary infection until D42, infectious PEDV capable of horizontal transmission to naive pigs was only shed 14-16 days after infection to age-matched pigs. Homologous re-challenge 49 days post initial PEDV exposure did not result in re-infection of the pigs. This demonstrates potential for an effective PEDV vaccine

Next Generation Mapping of Enological Traits in an F2 Interspecific Grapevine Hybrid Family

In winegrapes (Vitis spp.), fruit quality traits such as berry color, total soluble solids content (SS), malic acid content (MA), and yeast assimilable nitrogen (YAN) affect fermentation or wine quality, and are important traits in selecting new hybrid winegrape cultivars. Given the high genetic diversity and heterozygosity of Vitis species and their tendency to exhibit inbreeding depression, linkage map construction and quantitative trait locus (QTL) mapping has relied on F1 families with the use of simple sequence repeat (SSR) and other markers. This study presents the construction of a genetic map by single nucleotide polymorphisms identified through genotyping-by-sequencing (GBS) technology in an F2 mapping family of 424 progeny derived from a cross between the wild species V. riparia Michx. and the interspecific hybrid winegrape cultivar, ‘Seyval’. The resulting map has 1449 markers spanning 2424 cM in genetic length across 19 linkage groups, covering 95% of the genome with an average distance between markers of 1.67 cM. Compared to an SSR map previously developed for this F2 family, these results represent an improved map covering a greater portion of the genome with higher marker density. The accuracy of the map was validated using the well-studied trait berry color. QTL affecting YAN, MA and SS related traits were detected. A joint MA and SS QTL spans a region with candidate genes involved in the malate metabolism pathway. We present an analytical pipeline for calling intercross GBS markers and a high-density linkage map for a large F2 family of the highly heterozygous Vitis genus. This study serves as a model for further genetic investigations of the molecular basis of additional unique characters of North American hybrid wine cultivars and to enhance the breeding process by marker-assisted selection. The GBS protocols for identifying intercross markers developed in this study can be adapted for other heterozygous species