Search results for "Genetic Variation"
showing 10 items of 836 documents
VP7 and VP4 Sequence Analyses of Rotavirus Strains From Italian Children With Viraemia and Acute Diarrhoea
2010
Background: Rotavirus has a high genetic variability. Point mutations, accumulating at a high rate, and genetic reassortment events have been well-documented. Viremia occurs commonly in children with acute rotavirus diarrhoea. However, information on genetic characterization of strains associated with systemic infection is poor. Objective: We evaluated prospectively children hospitalized for acute rotavirus diarrhoea and genotyped strains obtained from blood and stool samples. Nucleotide sequences within the VP4 ad VP7 genes of strains obtained from blood and stool specimens of the same patient were compared. Methods: Study subjects were 11 children admitted with acute rotavirus diarrhoea, …
Genetic heterogeneity of porcine enteric caliciviruses identified from diarrhoeic piglets
2008
Enteric caliciviruses (noroviruses and sapoviruses) are responsible for the majority of non-bacterial gastroenteritis in humans of all age groups. Analysis of the polymerase and capsid genes has provided evidence for a huge genetic diversity, but the understanding of their ecology is limited. In this study, we investigated the presence of porcine enteric caliciviruses in the faeces of piglets with diarrhoea. A total of 209 samples from 118 herds were analysed and calicivirus RNA was detected by RT-PCR in 68 sample (32.5%) and in 46 herds (38.9%), alone or in mixed infection with group A and C rotaviruses. Sequence and phylogenetic analysis of the calicivirus-positive samples characterized t…
GENETIC AND ENVIRONMENTAL VARIATION IN ANTIBODY AND T-CELL MEDIATED RESPONSES IN THE GREAT TIT
2006
Host parasite coevolution assumes pathogen specific genetic variation in host immune defense. Also, if immune function plays a role in the evolution of life history, allocation to immune function should be heritable. We conducted a cross-fostering experiment to test the relative importance of genetic and environmental sources of variation in T-cell mediated inflammatory response and antigen specific antibody responses in the great tits Parus major. Cell mediated response was measured during the nestling period and antibody response against two novel antigens was measured in two-month-old juveniles raised in a laboratory. We found no effect of nest of origin, but a strong effect of rearing e…
Simultaneous bilateral occurrence of a M. extensor digiti medii and a M. extensor digitorum brevis.
1993
Summary For the first time, the simultaneous and bilateral occurrence of two variants of the extensors of the fingers, M. extensor digiti medii and M. extensor digitorum brevis, is reported. The extensor of the middle finger arises from the distal fourth of the radius and runs to the base of the proximal phalanx. The short extensor of the fingers arises from the metacarpal region and inserts into the dorsal aponeurosis. Both muscles are innervated by the R. profundus n. radialis.
Association between Opioid Receptor mu 1 (OPRM1) Gene Polymorphisms and Tobacco and Alcohol Consumption in a Spanish Population.
2015
Evidence gained from animals and humans suggests that the encephalic opioid system might be involved in the development of drug addiction through its role in reward. Our aim is to assess the influence of genetic variations in the opioid receptor mu 1 on alcohol and tobacco consumption in a Spanish population. 763 unrelated individuals (465 women, 298 men) aged 18-85 years were recruited between October 2011 and April 2012. Participants were requested to answer a 35-item questionnaire on tobacco and alcohol consumption, as well as to complete the AUDIT and Fagerström tests. Individuals were genotyped for three polymorphisms in the opioid receptor mu 1 (OPRM1) gene, using a TaqMan® protocol. …
Hepatocytes--the choice to investigate drug metabolism and toxicity in man: in vitro variability as a reflection of in vivo.
2007
The pharmaceutical industry is committed to marketing safer drugs with fewer side effects, predictable pharmacokinetic properties and quantifiable drug-drug interactions. Drug metabolism is a major determinant of drug clearance and interindividual pharmacokinetic differences, and an indirect determinant of the clinical efficacy and toxicity of drugs. Progressive advances in the knowledge of metabolic routes and enzymes responsible for drug biotransformation have contributed to understanding the great metabolic variations existing in human beings. Phenotypic as well genotypic differences in the expression of the enzymes involved in drug metabolism are the main causes of this variability. How…
Increasing growth temperature alters the within-host competition of viral strains and influences virus genetic variation
2020
AbstractThe emergence of viral diseases in plant crops hamper the sustainability of food production, and this may be boosted by global warming. Concurrently, mixed viral infections are becoming common in plants, of which epidemiology are unpredictable due to within-host virus-virus interactions. However, the extent in which the combined effect of variations in the abiotic components of the plant ecological niche (e.g., temperature) and the prevalence of mixed infections (i.e., within-host interactions among viruses) affect the evolutionary dynamics of viral populations is not well understood. Here, we explore the interplay between ecological and evolutionary factors during viral infections,…
Genetic variability of the blue and red shrimp Aristeus antennatus in the Western Mediterranean Sea inferred by DNA microsatellite loci
2011
Genetic variation at eight microsatellite loci was studied in nine populations of the blue and red shrimp Aristeus antennatus to investigate whether distinct stocks are present in the Western Mediterranean Sea. A high level of gene flow and no evidence of genetic partitioning were discovered. No significant variation was found (FST = 0.00673, P-value = 0.067) even when shrimps from exploited and those from deep-water unexploited grounds were compared. No evidence of reduction or expansion of population size in the recent past was found, as indicated by the bottleneck and interlocus g-tests. Our results are consistent with previous studies using mitochondrial gene methods and allozymes, indi…
Population dynamic of the extinct European aurochs: genetic evidence of a north-south differentiation pattern and no evidence of post-glacial expansi…
2010
International audience; Abstract Background The aurochs ( Bos primigenius ) was a large bovine that ranged over almost the entirety of the Eurasian continent and North Africa. It is the wild ancestor of the modern cattle ( Bos taurus ), and went extinct in 1627 probably as a consequence of human hunting and the progressive reduction of its habitat. To investigate in detail the genetic history of this species and to compare the population dynamics in different European areas, we analysed Bos primigenius remains from various sites across Italy. Results Fourteen samples provided ancient DNA fragments from the mitochondrial hypervariable region. Our data, jointly analysed with previously publis…
Variation in spawning time promotes genetic variability in population responses to environmental change in a marine fish.
2015
Common-garden experiments suggest that the response of Atlantic cod larvae to temperature differs among populations that spawn at different times of year. Populations appear to be adapted to the temperatures experienced during the larval stage at a small spatial scale, despite a lack of physical barriers to gene flow.