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D Marinković

Publications and source records attributed to D Marinković.

18 recordsLinked to original sources
PubMed1995

Adaptive significance of amylase polymorphism in Drosophila. X. Analysis of alpha-amylase activity of two amylase variants in individual Drosophila subobscura flies.

Experiments were designed to estimate the variation of alpha-amylase activity in Drosophila subobscura individuals homozygous for AmyS and AmyF alleles at the Amy locus. The measurements of enzyme activities in six groups of male progenies determined in each individual have shown that degree of variation differs between S and F strains. Variability of amylase activity among male progenies of S strain was substantially greater, which also had significantly higher specific amylase activity than in F strain. The analysis of amylase activity variance showed that this variance among the males is 40 times, and among the females 2.7 times smaller in F than in S strain.

Adaptation, Biological↗
PubMed1991

Neuroleptic actions on the thyroid axis: different effects of clozapine and haloperidol.

Twenty-six in-patients treated for schizophrenia, were divided in two groups. The first group received haloperidol, 20-40 mg p.d., and the second, clozapine, 150-250 mg p.d. TRH-TSH test was performed by injecting 0.2 mg TRH. Four drug-free schizophrenic patients gave normal TSH response to TRH, as well as the group of patients treated with haloperidol. Contrary to that, the clozapine-treated group showed a blunted TSH response. The results obtained are discussed in terms of the different pharmacological profiles of haloperidol and clozapine, especially regarding their dopaminergic actions, alpha-adrenergic and serotonergic control upon thyroid axis.

Adult↗
PubMed1990

Inheritance of acute appendicitis: familial aggregation and evidence of polygenic transmission.

We explored familiality as well as the heritability and possible mode(s) of inheritance of acute appendicitis in childhood and early adolescence. Our case-control study showed that a positive family history for reported appendectomy was significantly more frequent in families of 80 consecutive patients eventually proved to have histopathologic acute appendicitis than in families of surgical controls matched for sex, age, and number of siblings. The relative risk was 10.0 (95% confidence limits 4.7-21.4). The pattern of familial aggregation was further supported by the fact that the age-standardized morbidity ratio was four times greater among family members of cases than among controls. We then applied the unified mixed model of segregation analysis, as implemented in the computer program POINTER, to a new set of 100 multigenerational pedigrees of children with histopathologically confirmed acute appendicitis that were broken down into 674 nuclear families. Age-specific morbidity risk and lifetime incidence of acute appendicitis were estimated from relatives of controls matched for age and sex to probands. Complex segregation analysis supported a polygenic or multifactorial model with a total heritability of 56%. There was no evidence to support a major gene, although a rare gene could not be ruled out as the cause of a small proportion of cases. Specific studies to address genetic and environmental factors in this serious disease seem worthwhile; but, for now, a positive family history of appendicitis might join other evidence leading to improved clinical recognition of acute appendicitis.

Acute Disease↗
PubMed1990

Genetic basis of resistance to trauma in inbred strains of mice.

In this study the resistance to mechanical, thermal, and radiation trauma in four inbred strains of mice (AKR, BALB/c, CBA, and C57Bl/6) was compared with the degree of genetic resemblance, by analyzing the allozyme variabilities of these strains. It was shown that the highest degree of genetic resemblance was among CBA and AKR strains, which correlated with a similar degree of resistance to trauma. On the other hand, BALB/c and C57Bl/6 strains expressed significant differences, both genetically and with respect to the responses to trauma. The hypothesis is introduced that the genetic determination of the resistance to trauma is based on: a) a polygenic control of general physiological homeostasis, with the possibility that b) some specific genes or single loci may contribute more than others to such adaptations of the strains tested.

Alleles↗
PubMed1988

Parental age dependent changes as a source of genetic variation in Drosophila melanogaster.

It has been shown repeatedly that numerous cumulative changes occur in chromosomes of D. melanogaster, as an effect of ageing which, especially in the homozygous state, significantly affect different fitness components of their carriers. It appears that the observed age-affected events are produced by systematic and ontogenetically programmed changes in genetic loads at specific chromosomes, which are transferable to following generations. It has been suggested that such changes could be of mutational origin, and that they could be more frequent at gene loci which are epigenetically active during ontogenesis. It was demonstrated that a large sample of identical chromosomes behave quite differently in the homozygous state when obtained from aged compared to non-aged parents, producing a significant decrease in relative viability, length of preadult development, and longevity of their carriers, as well as in the frequency of recombinations of corresponding chromosomes. A specific treatment by streptomycin resulted in remarkably milder effects of ageing, which is in accordance with the statement of some authors that such a treatment may diminish the frequency of spontaneous recessive mutations in their carriers. Thus the observed age-affected changes could be an important source of developmental and evolutionary variation of living organisms.

Aging↗
PubMed1987

Correlations between development rates, enzyme activities, ribosomal DNA spacer-length phenotypes, and adaptation in Drosophila melanogaster.

Selection for "fast" preadult development rate among the progeny of flies collected in a natural population of Drosophila melanogaster produced a line that developed more rapidly than a line selected for "slow" preadult development rate. Assays for enzyme activity levels showed that the activities of alpha-glycerophosphate dehydrogenase, alcohol dehydrogenase, and malic enzyme were higher in the fast than in the slow line, but that the activity of superoxide dismutase was lower in the fast line. Differences in the frequencies of spacer-length phenotypes of X chromosome-linked rRNA genes (rDNA), which developed between the lines during the selection process, are larger than can be explained on the basis of genetic drift alone. Long rDNA spacers had high frequency in the fast line; short spacers, in the slow line. We conclude that enzyme levels affected adaptation under the selective regimes imposed and that the different X-linked rDNA spacer-length phenotypes are either adaptive in themselves or that they mark chromosomal segments carrying genes relevant to adaptation.

Adaptation, Physiological↗
PubMed1979

Erythropoietin in patients with anaemia in rheumatoid arthritis.

Iron status and erythropoietin (Ep) level in serum and urine were determined in 30 patients with anaemia in rheumatoid arthritis. The anaemia in these patients was mild and fulfilled the criteria for anaemia of chronic disorders. The iron status of these patients differed from the iron status in patients with sideropenic anaemia. Serum Ep, level, measured indirectly by the polycythaemic mouse bioassay, was either not detected or when detected it did not correspond to the degree of anaemia. The data suggest that the failure to produce sufficient amount of Ep, among other causes, could be important in the pathogenesis of anaemia in rheumatoid arthritis.

Adult↗
PubMed1975

Fitness of allozyme variants in Drosophila pseudoobscura. I. Selection at the PGM-1 and Me-2 loci.

We have studied in Drosophila pseudoobscura the effect of allozyme variation on seven fitness components: female fecundity, egg hatchability, egg-to-adult survival under near-optimal and under competitive conditions, rate of development under near-optimal and under competitive conditions, and mating capacity of males. Three genotypes at each of two loci, Pgm-1 and Me-2, have been studied in various combinations. These two loci are highly polymorphic in natural populations of D. pseudoobscura. Statistically significant differences involving one or more genotypes exist for all components of fitness. No single genotype is best for all fitness components; rather the relative fitnesses of genotypes are reversed when different parameters are considered, or when they are studied in different environmental conditions. Also, the average egg-to-adult survival and rate of development are better when different genotypes are reared together than when they occur in pure culture. Four different modes of selection have been uncovered by our experiments. These forms of selection may account for the persistence of the two allozyme polymorphisms in nature, and for previously observed seasonal fluctuations of the allelic frequencies in natural populations.

Animals↗
PubMedDate not supplied

Variability of haptoglobin and alpha 2-macroglobulin in Albino Oxford and Dark Augustin inbred strains of rats before and after trauma.

Increased synthesis of acute-phase proteins (APP) in the liver represents the most prominent aspect of acute phase reaction (APR). Haptoglobin (Hp) and alpha 2-macroglobulin (alpha 2-M) are among the most important APP in rats. In this study AO (Albino Oxford) and DA (Dark Augustin) inbred strains of rats, with different resistance to trauma, were used to compare concentrations of Hp, alpha 2-M, IL-1, IL-6 and TNF, before and after tourniquet trauma. Cytokines IL-1, IL-6 and TNF have an important role in APP gene expression. Our results showed that before trauma, more resistant AO rats had higher concentrations of Hp and alpha 2-M compared to DA rats. The influence of genetic elements of these differences is significant. Tourniquet trauma caused an early increase of IL-1, IL-6 and TNF activities in the serum which preceded the increase in the Hp and alpha 2-M concentrations but differences between strains were not found.

Animals↗
PubMedDate not supplied

[Man and his genes].

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Chromosome Mapping↗