40 research outputs found
Genetic Diversity Analysis of Mutant Lines of Oat (\u3cem\u3eAvena sativa\u3c/em\u3e L.) Based on RAPD and ISSR Analysis
The genus Avena belongs to the grass family Poaceae and has ploidy levels of diploid, tetraploid and hexaploid with basic chromosome number of 7 (n=7). Oat (Avena sativa L.) is one of the most important forage and feed crops of the world. Oat is used as green fodder, straw, hay or silage. Oat grain makes a good balanced concentrate in the rations for poultry, cattle, sheep and other animals. Green fodder contains about 10 to 13% protein and 30 to 35% dry matter. Despite being high fed fodder crop, it is now gaining importance as food due to its unique and important quality characteristics, particularly the lipid and protein in grains (Ruwali et al., 2013). The existing genetic variability for the traits of agronomic importance, such as plant vegetative cycle, is considered restricted. The narrow of the genetic base in cultivated oat varieties can be a constraint on the efficacy of genotype selection in segregating generations (Carvalho and Federizzi, 1989). Genetic variability in existing oat cultivars is not high enough; it hampers the selection of superior genotypes for breeding. Modifications in the genetic structure of plants and an organisms occurs naturally, though at low frequency, but can be increased through physical or chemical mutagens.
Advances in molecular biology have introduced an alternative for variety/genotype identification. The genetic characterization of germplasm helps in their effective conservation and reveals the extent of relationship among the accessions and the estimates of genetic diversity (Singh et al., 2012). The selection of RAPD and ISSR were based on their relative technical simplicity, level of polymorphism they detect, cost effective, easily applicable to any plant species and target those sequence which are abundant throughout the eukaryotic genome and are rapidly evolved. A series of studies have indicated that ISSR could be able to produce more reliable and reproducible bands because of the higher annealing temperature and longer sequence of ISSR primers considered superior than RAPD (Bornet et al., 2001). ISSR has proved to be useful to study of population genetic studies gene mapping germplasm identification and characterize gene bank accessions as well as to identify closely related cultivars (Cortesi et al., 2004). The present research had the following objectives: Assessment of diversity of mutant lines of oat (Avena sativa L.) based on RAPD and ISSR analysis
The Short-Term Effect of Weight Loss Surgery on Volumetric Breast Density and Fibroglandular Volume
Purpose:
Obesity and breast density are both associated with an increased risk of breast cancer and are potentially modifiable. Weight loss surgery (WLS) causes a significant reduction in the amount of body fat and a decrease in breast cancer risk. The effect of WLS on breast density and its components has not been documented. Here, we analyze the impact of WLS on volumetric breast density (VBD) and on each of its components (fibroglandular volume and breast volume) by using three-dimensional methods.
Materials and Methods:
Fibroglandular volume, breast volume, and their ratio, the VBD, were calculated from mammograms before and after WLS by using Volparaâ„¢ automated software.
Results:
For the 80 women included, average body mass index decreased from 46.0 ± 7.22 to 33.7 ± 7.06 kg/m2. Mammograms were performed on average 11.6 ± 9.4 months before and 10.1 ± 7 months after WLS. There was a significant reduction in average breast volume (39.4 % decrease) and average fibroglandular volume (15.5 % decrease), and thus, the average VBD increased from 5.15 to 7.87 % (p < 1 × 10−9) after WLS. When stratified by menopausal status and diabetic status, VBD increased significantly in all groups but only perimenopausal and postmenopausal women and non-diabetics experienced a significant reduction in fibroglandular volume.
Conclusions:
Breast volume and fibroglandular volume decreased, and VBD increased following WLS, with the most significant change observed in postmenopausal women and non-diabetics. Further studies are warranted to determine how physical and biological alterations in breast density components after WLS may impact breast cancer risk.ECU Open Access Publishing Support Fun
5'-Substituted guanosine derivatives as potential ligands at the [3H]guanosine binding site.
Adenine based acyclic-nucleotides as novel P2X3 receptor ligands
A new series of acyclic nucleotides based on the adenine skeleton and bearing in 9-position a phosphorylated four carbon chain has been synthesized. Various substituents were introduced in 2-position of the adenine core. The new compounds were evaluated on rat P2X3 receptors, using patch clamp recording from HEK transfected cells and the full P2X3 agonist R,β-meATP as reference compound. The results suggest that certain acyclic nucleotides, in particular compounds 28 and 29, are endowed with modest partial agonism on P2X3 receptors. This is an interesting property that can depress the function of P2X3 receptors, whose activation is believed to be involved in a number of
chronic pain conditions including neuropathic pain and migraine. In fact, the new acyclic nucleotides are able to persistently block (by desensitization) P2X3 receptor activity after a brief, modest activation,
yet leaving the ability of sensory neurons to mediate responses to standard painful stimuli via a lower level of signaling
Evaluation of adenine as scaffold for the development of novel P2X3 receptor antagonists
Ligands that selectively block P2X3 receptors localized on nociceptive sensory fibres may be useful for the treatment of chronic pain conditions including neuropathic pain, migraine, and inflammatory pain. With the aim at exploring the suitability of adenine moiety as a scaffold for the development of antagonists of this receptor, a series of 9-benzyl-2-aminoadenine derivatives were designed and synthesized. These new compounds were functionally evaluated at rat or human P2X3 receptors expressed in human embryonic kidney (HEK) cells and on native P2X3 receptors from mouse trigeminal ganglion sensory neurons using patch clamp recording under voltage clamp configuration. The new molecules behaved as P2X3 antagonists, as they rapidly and reversibly inhibited (IC50 in the low micromolar range) the membrane currents induced via P2X3 receptor activation by the full agonist alpha,beta-methyleneATP. Introduction of a small lipophilic methyl substituent at the 6-amino group enhanced the activity, in comparison to the corresponding unsubstituted derivative, resulting in the 9-(5-iodo-2-isopropyl-4-methoxybenzyl)-N-6-methyl-9H-purine-2,6-diamine (24), which appears to be a good antagonist on recombinant and native P2X3 receptors with IC50 = 1.74 +/- 0.21 mu M. (C) 2013 Elsevier Masson SAS. All rights reserved