Sequence analysis of Potato leafroll virus isolates reveals genetic stability, major evolutionary events and differential selection pressure between overlapping reading frame products.
ABSTRACT In order to investigate the genetic diversity of Potato leafroll virus (PLRV), seven new complete genomic sequences of isolates collected worldwide were compared with the five sequences available in GenBank. Then, a restricted polymorphic region of the genome was chosen to further analyse new sequences. The sequences of PLRV open reading frames (ORFs) 3 and 4 were also compared with those of two other poleroviruses and the non-synonymous to synonymous substitution ratio distribution was analysed in overlapping and non-overlapping regions of the genome using maximum-likelihood models. Results confirmed that PLRV sequences from around the world are very closely related and showed that the region encoding protein P0 allowed the detection of three groups of isolates. When compared to other poleroviruses, PLRV was the most conserved in both ORFs 3 and 4. However, the results suggest that important events, such as deletion, mutation at a stop codon and intraspecific homologous recombination events, have occurred during the evolution of PLRV. Finally, it was shown that the translation products of ORFs 0 and 3 are significantly more conserved than those of the overlapping ORFs 1 and 4, respectively. All together, the results allow the proposal of new hypotheses to explain the apparent genetic stability of PLRV and its evolution.
Article: Sweet Chestnut (Castanea sativa Mill.) Bark Extract: Cardiovascular Activity and Myocyte Protection against Oxidative Damage.[show abstract] [hide abstract]
ABSTRACT: This work was aimed at evaluating the cardioprotective effects of Castanea sativa Mill. (CSM) bark extract characterized in its phenolic composition by HPLC-DAD-MS analysis. The study was performed using primary cultures of neonatal rat cardiomyocytes to investigate the antioxidant and cytoprotective effects of CSM bark extract and isolated guinea pig left and right atria, left papillary muscle, and aorta to evaluate its direct effect on cholinergic and adrenergic response. In cultured cardiomyocytes the CSM bark extract reduced intracellular reactive oxygen species formation and improved cell viability following oxidative stress in dose-dependent manner. Moreover, the extract decreased the contraction induced by noradrenaline (1 μ M) in guinea pig aortic strips and induced transient negative chronotropic and positive inotropic effects without involvement of cholinergic or adrenergic receptors in the guinea pig atria. Our results indicate that CSM bark extract exhibits antioxidant activity and might induce cardioprotective effect.Oxidative medicine and cellular longevity 01/2013; 2013:471790. · 2.84 Impact Factor
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ABSTRACT: Ischemic heart disease (IHD) is one of the leading causes of death in Western countries. Prevention rather than treatment of heart disease can significantly improve patients' quality of life and reduce health care costs. Flavonoids are widely distributed in vegetables, fruits and herbal medicines. Regularly consuming botanicals, especially those containing flavonoids, has been associated with a reduction in cardiovascualar disease; thus, it is important to investigate how flavonoids improve cardiac resistance to heart disease and their related mechanisms of action. It has been shown that cardiomyocyte injury and death can result from ischemia-reperfusion, which is pathognomonic of ischemic heart disease. Massive reactive oxygen species (ROS) release at the onset of reperfusion produces cell injury and death. "Programming" the heart to either generate less ROS or to increase strategic ROS removal could reduce reperfusion response. Additionally, profuse nitric oxide (NO) release at reperfusion could be protective in "preconditioning" models. Botanical flavonoids induce preconditioning of the heart, thereby protecting against ischemia-reperfusion injury. In this article, we will discuss two herbs containing potent flavonoids, Scutellaria baicalensis and grape seed proanthocyanidin, which can potentially offer cardiac protection against ischemic heart disease.The American Journal of Chinese Medicine 01/2011; 39(4):661-71. · 1.98 Impact Factor
Conference Proceeding: Towards Automatic Detecting of Overlapping Genes - Clustered BLAST Analysis of Viral Genomes.Evolutionary Computation, Machine Learning and Data Mining in Bioinformatics, 8th European Conference, EvoBIO 2010, Istanbul, Turkey, April 7-9, 2010. Proceedings; 01/2010