scholarly journals The Evolutionary Processes of Canine Coronaviruses

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Annamaria Pratelli
Keyword(s):  
Mutation Frequency ◽  
Diagnostic Methods ◽  
Evolutionary Processes ◽  
Pathogenetic Role ◽  
High Mutation Frequency ◽  
Canine Coronavirus ◽  
Virus Strains

Since the first identification of the virus in 1971, the disease caused by canine coronavirus (CCoV) has not been adequately investigated, and the role that the virus plays in canine enteric illness has not been well established. Only after the emergence in 2002 of SARS in human has new attention been focused on coronaviruses. As a consequence of the relatively high mutation frequency of RNA-positive stranded viruses, CCoV has evolved and, with the biomolecular techniques developed over the last two decades, new virus strains, serotypes, and subtypes have been identified in infected dogs. Considering the widespread nature of CCoV infections among dog populations, several studies have been carried out, focusing upon the epidemiological relevance of these viruses and underlining the need for further investigation into the biology of CCoVs and into the pathogenetic role of the infections. This paper reports the evolutionary processes of CCoVs with a note onto recent diagnostic methods.

scholarly journals Superoxide is a mediator of an altruistic aging program in Saccharomyces cerevisiae

2004 ◽  
Vol 166 (7) ◽  
pp. 1055-1067 ◽  
Author(s):  
Paola Fabrizio ◽  
Luisa Battistella ◽  
Raffaello Vardavas ◽  
Cristina Gattazzo ◽  
Lee-Loung Liou ◽  
...  
Keyword(s):  
Mutation Frequency ◽  
Premature Aging ◽  
Natural Environments ◽  
Computational Simulations ◽  
Changing Environments ◽  
High Mutation Frequency ◽  
Aging Program ◽  
Programmed Aging ◽  
Age Dependent

Aging is believed to be a nonadaptive process that escapes the force of natural selection. Here, we challenge this dogma by showing that yeast laboratory strains and strains isolated from grapes undergo an age- and pH-dependent death with features of mammalian programmed cell death (apoptosis). After 90–99% of the population dies, a small mutant subpopulation uses the nutrients released by dead cells to grow. This adaptive regrowth is inversely correlated with protection against superoxide toxicity and life span and is associated with elevated age-dependent release of nutrients and increased mutation frequency. Computational simulations confirm that premature aging together with a relatively high mutation frequency can result in a major advantage in adaptation to changing environments. These results suggest that under conditions that model natural environments, yeast organisms undergo an altruistic and premature aging and death program, mediated in part by superoxide. The role of similar pathways in the regulation of longevity in organisms ranging from yeast to mice raises the possibility that mammals may also undergo programmed aging.

Histopathological Proof of the Pathogenetic Role of a Rare GFAP Mutation in Alexander´s Disease with Isolated Flaccid Paraparesis

2017 ◽  
Vol 48 (S 01) ◽  
pp. S1-S45
Author(s):  
F. Brackmann ◽  
R. Coras ◽  
K. Rössler ◽  
O. Rompel ◽  
R. Trollmann
Keyword(s):  
Pathogenetic Role

Imbalance in the system L-arginin-NO in pathogenesis of obstetric complications and intrauterine growth retardation (Literature review)

2016 ◽  
pp. 43-47
Author(s):  
O.V. Basystyi ◽  
Keyword(s):  
Nitric Oxide ◽  
Literature Review ◽  
Growth Retardation ◽  
Intrauterine Growth Retardation ◽  
Obstetric Complications ◽  
Pathogenetic Role ◽  
Intrauterine Growth ◽  
System L ◽  
Nitric Oxide Deficiency

The data of domestic and foreign literature on etiology, pathogenesis and intrauterine growth retardation diagnosis are presented in the paper. It highlights pathogenetic role of nitric oxide deficiency in case of obstetric complications and intrauterine growth retardation. Key words: intrauterine growth retardation (IUGR), system L-arginin–NO, obstetric complications.

Pathogenetic role of Campylobacter pyloridis in gastric ulcer

1987 ◽  
Vol 2 (4) ◽  
pp. 309-316 ◽  
Author(s):  
WAI-MO HUI ◽  
SHIU-KUM LAM ◽  
PAT-YIM CHAU ◽  
JOANA HO ◽  
WAN-YEE LAU ◽  
...  
Keyword(s):  
Gastric Ulcer ◽  
Pathogenetic Role ◽  
Campylobacter Pyloridis

scholarly journals Human Rev1 relies on insert-2 to promote selective binding and accurate replication of stabilized G-quadruplex motifs

2021 ◽  
Author(s):  
Amit Ketkar ◽  
Lane Smith ◽  
Callie Johnson ◽  
Alyssa Richey ◽  
Makayla Berry ◽  
...  
Keyword(s):  
Amino Acids ◽  
Mutation Frequency ◽  
Control Sequence ◽  
Wild Type ◽  
Binding Properties ◽  
High Affinity ◽  
G4 Dna ◽  
G Quadruplex ◽  
Forward Mutagenesis

Abstract We previously reported that human Rev1 (hRev1) bound to a parallel-stranded G-quadruplex (G4) from the c-MYC promoter with high affinity. We have extended those results to include other G4 motifs, finding that hRev1 exhibited stronger affinity for parallel-stranded G4 than either anti-parallel or hybrid folds. Amino acids in the αE helix of insert-2 were identified as being important for G4 binding. Mutating E466 and Y470 to alanine selectively perturbed G4 binding affinity. The E466K mutant restored wild-type G4 binding properties. Using a forward mutagenesis assay, we discovered that loss of hRev1 increased G4 mutation frequency >200-fold compared to the control sequence. Base substitutions and deletions occurred around and within the G4 motif. Pyridostatin (PDS) exacerbated this effect, as the mutation frequency increased >700-fold over control and deletions upstream of the G4 site more than doubled. Mutagenic replication of G4 DNA (±PDS) was partially rescued by wild-type and E466K hRev1. The E466A or Y470A mutants failed to suppress the PDS-induced increase in G4 mutation frequency. These findings have implications for the role of insert-2, a motif conserved in vertebrates but not yeast or plants, in Rev1-mediated suppression of mutagenesis during G4 replication.

scholarly journals SPONTANEOUS UNSTABLE UNC-22 IV MUTATIONS IN C. ELEGANS VAR. BERGERAC

Genetics ◽  
1984 ◽  
Vol 108 (4) ◽  
pp. 859-877
Author(s):  
D G Moerman ◽  
R H Waterston
Keyword(s):  
Mutation Frequency ◽  
Spontaneous Mutation ◽  
Phenotypic Effect ◽  
C Elegans ◽  
High Mutation Frequency ◽  
Mutator Activity ◽  
Discrete Site ◽  
Unstable Mutations ◽  
Spontaneous Mutation Frequency ◽  
Forward Mutation

ABSTRACT This paper describes a mutator system in the nematode Caenorhabditis elegans var. Bergerac for the gene unc-22. Of nine C. elegans and two C. briggsae strains tested only the Bergerac BO strain yielded mutant animals at a high frequency and the unc-22 IV gene is a preferred mutational target. The forward spontaneous mutation frequency at the unc-22 locus in Bergerac BO is about 1 × 10-4, and most of these spontaneous unc-22 mutations revert at frequencies between 2 × 10-3 and 2 × 10-4. Both the forward mutation frequency and the reversion frequency are sensitive to genetic background. Spontaneous unc-22 mutations derived in a Bergerac background and placed in a primarily Bristol background revert at frequencies of <10-6. When reintroduced into a Bergerac/Bristol hybrid background the mutations once again become unstable. The mutator activity could not be localized to a discrete site in the Bergerac genome. Nor did mutator activity require the Bergerac unc-22 gene as a target since the Bristol unc-22 homolog placed in a Bergerac background also showed high mutation frequency. Intragenic mapping of two spontaneous unc-22 alleles, st136 and st137, place both mutations in the central region of the known unc-22 map. However, these mutations probably recombine with one another, suggesting that the unstable mutations can occur in more than one site in unc-22. Examination of the phenotypic effect of these mutations on muscle structure indicates that they are less severe in their effect than a known amber allele. We suggest that this mutator system is polygenic and dispersed over the nematode genome and could represent activity of the transposable element Tc1.

scholarly journals NKCC1 and NKCC2: The pathogenetic role of cation-chloride cotransporters in hypertension

2015 ◽  
Vol 2 (2) ◽  
pp. 186-196 ◽  
Author(s):  
Sergei N. Orlov ◽  
Svetlana V. Koltsova ◽  
Leonid V. Kapilevich ◽  
Svetlana V. Gusakova ◽  
Nickolai O. Dulin
Keyword(s):  
Pathogenetic Role ◽  
Cation Chloride Cotransporters

Clinical and pathogenetic role of state of prooxidant-antioxidant regulation in patients with purulent meningitis in the dynamics of disease

2014 ◽  
Vol 18 (4 (72)) ◽  
Author(s):  
D. A. Zadyraka ◽  
E. V. Riabokon
Keyword(s):  
Free Radical ◽  
Conventional Treatment ◽  
Free Radical Oxidation ◽  
Oxidative Modification ◽  
Blood Proteins ◽  
Radical Oxidation ◽  
Pathogenetic Role ◽  
Purulent Meningitis ◽  
Laboratory Changes

The paper shows, that patients with purulent meningitis on the background of severe clinical and laboratory changes had a disturbance of prooxidant-antioxidant regulation with a shift towards activation of free radical oxidation. In the dynamics of the disease, after 7-10 days of conventional treatment, against the background of a reduction of cephalic and meningeal syndromes intensity, a normalization of liquor and hemogram indices, in most patients there was a further decrease in catalase activity and an increase of nitrites, of parameters of spontaneous and induced oxidative modification of blood proteins that remained when the patients were discharged, compared with healthy people.

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