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At least 253 records · Page 14Linked to original sources
PubMed1982

[Blood cortisol level variations in burn patients and their relation to variations in plasma amino acids. Biochemical study of 19 subjects].

Cortisolemia from burn patients is measured during 28 days. The relation between the cortisolemia and values from 16 plasma amino acids is studied on the fourth and on the seventh day after injury. Cortisolemia is higher in the severely burned patients than in mild injured patients. A correlation between the burn surface area and the cortisolemia is found on day four and on day seven. Cortisolemia is also higher in nonsurvivors than in survivors. Plasma methionine, on day four, and plasma phenylalanine, on day seven, are correlated with cortisolemia. This result suggests that hyperphenylalaninemia results from protein breakdown which is essentially cortisol-mediated. However, cortisol does not seem to have a central place in control of amino acidemia after burn injury.

Amino Acids↗
PubMed1997

Allozyme variation in Parnassius mnemosyne (L.) (Lepidoptera) populations in North-East Hungary: variation within a subspecies group.

Allozyme polymorphism was studied in 11 Parnassius mnemosyne (Linnaeus, 1758) populations in North-East Hungary. Significant departures from Hardy-Weinberg equilibrium were observed in several cases due to heterozygote deficiency. Genetic variability did not display geographical pattern; the level of genetic differentiation was similar between adjacent populations and between populations originating from different geographical regions. Even a completely isolated population was not differentiated markedly from the others. Thus, genetic drift can be expected as the main evolutionary force acting in the populations.

Journal Article↗
PubMed1999

Population structure of North American beluga whales (Delphinapterus leucas) based on nuclear DNA microsatellite variation and contrasted with the population structure revealed by mitochondrial DNA variation

Beluga whales (Delphinapterus leucas) in North American waters migrate seasonally between wintering areas in broken pack ice and summering locations in estuaries and other open water areas in the Arctic and sub-Arctic. Results from our previous investigation of beluga whale mitochondrial DNA (mtDNA) revealed genetic heterogeneity among beluga from different summering locations that was interpreted as representing a high degree of summering site philopatry. However, mtDNA is maternally inherited and does not reflect mating that may occur among beluga from different summering locations in wintering areas or during annual migrations. To test the possibility that breeding occurs among beluga from different summering locations, genetic variability at five nuclear DNA (nDNA) microsatellite loci was examined in the same animals tested in the mtDNA study. Beluga samples (n = 640) were collected between 1984 and 1994 from 24 sites across North America, mostly during the summer. Whales from the various sites were categorized into eight summering locations as identified by mtDNA analysis, as well as four hypothesized wintering areas: Bering Sea, Hudson Strait (Hudson Strait, Labrador Sea, southwest Davis Strait), Baffin Bay (North Water, east Davis Strait), and St Lawrence River. Microsatellite allele frequencies indicated genetic homogeneity among animals from summering sites believed to winter together but differentiation among whales from some of the wintering areas. In particular, beluga from western North America (Bering Sea) were clearly distinguished from beluga from eastern North America (Hudson Strait, Baffin Bay, and St Lawrence River). Based upon the combined data set, the population of North American beluga whales was divided into two evolutionarily significant units. However, the population may be further subdivided into management units to reflect distinct groups of beluga at summering locations.

Journal Article↗
PubMed2006

[Short time variation of foetal heart rate: therapeutic management and effect on heart rate variation in the context of chronic hypotension in the 27th week of gestation].

The non-stress test is the most commonly used method in prepartal surveillance. Due to the high intra- and interobserver variability involved in subjective evaluation, the computer-assisted analysis is gaining in importance. Some studies have shown that low foetal STV may be associated with higher rates of acidosis and intrauterine mortality. Other factors influencing STV are largely not known. Low STV has been found as an effect of cortisone. In this case report, we illustrate the relevance of haemodilation therapy in the context of essential hypertension in the 27 (th) week of gestation and its effect on SVT. The treatment led to a prolongation of pregnancy to the 32 (nd) week. At the start of treatment STV increased to 4.5 ms and dropped back below this value concurrently with centralisation as documented by Doppler sonography. STV correlated clearly with the foetal condition. However, STV is dependent on numerous factors which should be investigated in further studies in order to determine appropriate reference values.

Cardiotocography↗
PubMed1999

Somatic sequence variation at the Friedreich ataxia locus includes complete contraction of the expanded GAA triplet repeat, significant length variation in serially passaged lymphoblasts and enhanced mutagenesis in the flanking sequence.

The vast majority of Friedreich ataxia patients are homozygous for large GAA triplet repeat expansions in intron 1 of the X25 gene. Instability of the expanded GAA repeat was examined in 23 chromosomes bearing 97-1250 triplets in lymphoblastoid cell lines passaged 20-39 times. Southern analyses revealed 18 events of significant changes in length ranging from 69 to 633 triplets, wherein the de novo allele gradually replaced the original over 1-6 passages. Contractions and expansions occurred with equal frequency and magnitude. This behavior is unique in comparison with other large, non-coding triplet repeat expansions [(CGG)(n)and (CTG)(n)] which remain relatively stable under similar conditions. We also report a rare patient who, having inherited two expanded alleles, showed evidence of contracted GAA repeats ranging from nine to 29 triplets in DNA from two independent peripheral blood samples. The GAA triplet repeat is known to adopt a triplex structure, and triplexes in transcribed templates cause enhanced mutagenesis. The poly(A) tract and a 135 bp sequence, both situated immediately upstream of the GAA triplet repeat, were therefore examined for somatic mutations. The poly(A) tract showed enhanced instability when in cis with the GAA expansion. The 135 bp upstream sequence was found to harbor a 3-fold excess of point mutations in DNA derived from individuals homozygous for the GAA triplet repeat expansion compared with normal controls. These data are likely to have important mechanistic and clinical implications.

Base Sequence↗