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Biomedical subjects

L Ollivier

Publications and source records attributed to L Ollivier.

49 records · Page 3Linked to original sources

Femoral infarction following intraarterial chemotherapy for osteosarcoma of the leg: a possible pitfall in magnetic resonance imaging.

Bone infarction of the distal femur is reported in two patients with osteosarcoma of the leg (1 tibia, 1 fibula) treated by preoperative chemotherapy including intraarterial chemotherapy (IAC) by Cis-platinum. Both patients were examined by magnetic resonance imaging before chemotherapy and again prior to limb salvage surgery. The location of these lesions in the distal femur must suggest bone infarction especially if the tumor has decreased in size under treatment.

Adult↗

Membrane proteins of the myocytes in cardiac overload.

Hypertrophy of the cardiac myocytes resulting from a mechanical overload may be responsible for major membraneous modifications, either at a sarcolemmal or at a sarcoplasmic level. In the present report, evaluation of several sarcolemmal markers such as beta-receptors, muscarinic receptors or (Na+,K+)-ATPase has been realized on an experimental model of cardiac hypertrophy performed on adult rats. Special attention has been taken to compare results expressed in densities or expressed in number of receptors present at the cellular level. For example, the beta-receptors density was 30% decreased whereas calculations of number of receptors present in the myocytes revealed an unchanged number (around 20,000 in both groups). The unmodified number could suggest a non regulation for the genes coding for the receptors.

Animals↗

Membrane proteins of the myocytes in cardiac overload.

1. Hypertrophy of the cardiac myocytes resulting from a mechanical overload may be responsible for major membraneous modifications, either at the sarcolemmal or at the sarcoplasmic level. In this study several sarcolemmal markers such as beta-adrenoceptors, muscarinic receptors or (Na+, K+)-ATPase were investigated in an experimental model of cardiac hypertrophy, the chronic aortic stenosis in adult rats. 2. Left ventricular beta-adrenoceptor density (expressed in fmol mg-1 protein) was decreased in the aortic stenosis group by about 30%; however, when expressed in number of receptors per cardiac cell beta-adrenoceptor number in the hypertrophied myocytes was unchanged. 3. Similarly, the number of muscarinic receptors in the hypertrophied cells, expressed as number of receptors per cardiac cell, was unchanged. 4. The number of (Na+, K+)-ATPase molecules with high affinity for ouabain was markedly increased in the hypertrophied myocytes, while those with low affinity for ouabain were not. 5. These results indicate the necessity in chronic hypertrophy to calculate receptors not only in density (fmol mg-1 protein) but also in number per cardiac cell. The unchanged number of beta-adrenergic and muscarinic receptors present on the hypertrophied myocytes suggests a non-regulation for the genes coding for these receptors.

Animals↗

[Influence of mineral diet of the sow on the sex ratio of the newborn].

This paper reports a study on sows to check the theory of Stolkowski which hypothesizes that mineral imbalance in the diet of the female before fertilization affects the sex ratio of the progeny. Relative excess of Na+ and K+ ions (NaK diet) would favour the birth of males, while relative excess of Ca2+ and Mg2+ ions (CaMg diet) would favour the birth of females. We carried out two successive experiments. In the first, sows were given the diet for about 34 days, the molar Na + K/Ca + Mg ratios being 2.1 for the NaK diet and 0.7 for the CaMg diet. Out of a total of 677 births, the sex ratio was 55.7 with the NaK diet and 48.3 with the CaMg diet. In the second experiment, the sows were treated for about 53 days and the molar ratios were 3.9 for the NaK diet and 0.5 for the CaMg diet. Out of a total of 869 piglets, the sex ratios were 50 and 53.5, respectively. Thus, the difference observed in experiment 1 (0.05 less than P less than 0.10), which agrees with the above mentioned theory, was reversed in experiment 2, the diet-experiment interaction being significant (P less than 0.05). Overall, the diet did not affect the sex ratio; the contradictory results of the two experiments showed no reproducible effect of dietary mineral imbalance on the sex ratio in pigs. There was also a significant diet-experiment interaction (P less than 0.05) as to litter size, and a nearly significant negative relationship between sex ratio and litter size was observed.

Animals↗

[The "hitch-hiking" effect of a selected gene and gamete combination (linkage disequilibrium): the example of 2 closely linked loci in the swine, Hal (halothane sensitivity) and PHI (phosphohexose isomerase)].

The observation of two lines of pigs selected differently for four generations confirms a recent theoretical work (Thomson, 1977) showing that a possible source of linkage disequilibrium may be the hitch-hiking effect of a selected locus (Hal) on another closely linked neutral locus (PHI).

Alleles↗

[Blood characteristics of some french pig populations. Relationships with the malignant hyperthermia syndrome (author's transl)].

Lactic acid, glucose, creatine phosphokinase (CPK) and some mineral components were determined in the blood of piglets before and after a halothane test of five minutes (only before for CPK). Two different experimental groups were studied: 222 Pietrain piglets from an INRA experimental herd, and 325 piglets from the Large White, French Landrace and Belgian Landrace breeds entering performance testing stations. Animals reacting positively to halothane ("MHS" piglets) have significantly higher blood levels of lactic acid and potassium before anesthesia than normal animals. CPK is also higher, except for the Belgian Landrace: in this breed CPK shows the same average value and distribution in the two groups of piglets (normal and MHS). There are also breed differences in blood magnesium, independently of the reaction to halothane. But the breed differences observed in lactic acid and CPK are related to the proportion of MHS piglets in each breed. Anesthesia by means of halothane lowers the measured blood characteristics--except for glucose--in normal animals, and rises them--except for potassium--in MHS piglets. The results are discussed in view of the incomplete discrimination between the two types of pigs, with a 5 minutes test, and, particularly, considering possible breed differences in that respect.

Anesthesia↗

Genetic diversity of eleven European pig breeds.

A set of eleven pig breeds originating from six European countries, and including a small sample of wild pigs, was chosen for this study of genetic diversity. Diversity was evaluated on the basis of 18 microsatellite markers typed over a total of 483 DNA samples collected. Average breed heterozygosity varied from 0.35 to 0.60. Genotypic frequencies generally agreed with Hardy-Weinberg expectations, apart from the German Landrace and Schwäbisch-Hällisches breeds, which showed significantly reduced heterozygosity. Breed differentiation was significant as shown by the high among-breed fixation index (overall F(ST)= 0.27), and confirmed by the clustering based on the genetic distances between individuals, which grouped essentially all individuals in 11 clusters corresponding to the 11 breeds. The genetic distances between breeds were first used to construct phylogenetic trees. The trees indicated that a genetic drift model might explain the divergence of the two German breeds, but no reliable phylogeny could be inferred among the remaining breeds. The same distances were also used to measure the global diversity of the set of breeds considered, and to evaluate the marginal loss of diversity attached to each breed. In that respect, the French Basque breed appeared to be the most "unique" in the set considered. This study, which remains to be extended to a larger set of European breeds, indicates that using genetic distances between breeds of farm animals in a classical taxonomic approach may not give clear resolution, but points to their usefulness in a prospective evaluation of diversity.

Journal Article↗

Detection of quantitative trait loci for growth and fatness in pigs.

A quantitative trait locus (QTL) analysis of growth and fatness data from a three-generation experimental cross between Meishan (MS) and Large White (LW) pig breeds is presented. Six boars and 23 F1 sows, the progeny of six LW boars and six MS sows, produced 530 F2 males and 573 F2 females. Nine growth traits, i.e. body weight at birth and at 3, 10, 13, 17 and 22 weeks of age, average daily gain from birth to 3 weeks, from 3 to 10 weeks and from 10 to 22 weeks of age, as well as backfat thickness at 13, 17 and 22 weeks of age and at 40 and 60 kg live weight were analysed. Animals were typed for a total of 137 markers covering the entire porcine genome. Analyses were performed using two interval mapping methods: a line-cross (LC) regression method where founder lines were assumed to be fixed for different QTL alleles and a half-/full-sib (HFS) maximum likelihood method where allele substitution effects were estimated within each half-/full-sib family. Both methods revealed highly significant gene effects for growth on chromosomes 1, 4 and 7 and for backfat thickness on chromosomes 1, 4, 5, 7 and X, and significant gene effects on chromosome 6 for growth and backfat thickness. Suggestive QTLs were also revealed by both methods on chromosomes 2 and 3 for growth and 2 for backfat thickness. Significant gene effects were detected for growth on chromosomes 11, 13, 14, 16 and 18 and for backfat thickness on chromosome 8, 10, 13 and 14. LW alleles were associated with high growth rate and low backfat thickness, except for those of chromosome 7 and to a lesser extent early-growth alleles on chromosomes 1 and 2 and backfat thickness alleles on chromosome 6.

Adipose Tissue↗

Selection for litter size in pigs. II. Efficiency of closed and open selection lines.

A selection experiment on litter size in the pig was carried on for seventeen generations in an Inra experimental herd. The founder population was made up of 10 males and 120 females from the Large White breed. Selection was first performed for ten generations in a closed line, compared to a control line derived from the same founder population. Selection was carried on within sire family on the total number of piglets born in the first two litters of the dam (TB1 + TB2). After ten generations, the selection criterion became dam TB1 only. The control line was then discontinued and a panel of frozen semen from the 11th generation boars was created for later comparisons. The selected line was opened to gilt daughters of hyperprolific boars and sows, at a rate of 1/8 per generation, and the same selection procedure was applied irrespective of the origin of the gilt. During the whole experiment, the number of ova shed (OS) and the number of live embryos (LE) at 30 days in the 3rd pregnancy were recorded. These two parts of the experiment were analysed using REML estimation of genetic parameters and a BLUP-Animal Model in order to estimate the responses to selection. Significant heritabilities for TB1, TB2, OS and LE were obtained, i.e. 0.10, 0.05, 0.43 and 0.19, respectively. Significant common environment variances and covariances were estimated for nearly all traits. Significantly positive BLUP responses per generation were observed from G0 to G17 for TB1 (+0.086), TB2 (+0.078), OS (+0.197) and LE (+0.157). However, the responses were 3- to 4-fold higher in the G12-G17 interval compared to G0-G11, and they were also in fair agreement with previous estimates based on standard least-squares procedures, using the control line and the control frozen semen panel. Since G11, the selection intensity was increased by nearly 80 p. cent compared to the previous generations, and the proportion of hyperprolific ancestry increased up to 65 p. cent in the sows of the last generation. The total genetic gain of about 1.4 piglets at birth per litter could be shared between a gain due to immigration, of about 0.8 piglets per litter, and a within-line selection gain of about 0.6 piglets. Thus by combining selection and immigration in the second part of the experiment, advantage could be taken from both the genetic superiority of the immigrants and the higher internal selection intensity made possible by immigration.

Animals↗