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V Roussel

Publications and source records attributed to V Roussel.

10 recordsLinked to original sources
PubMed2005

SSR allelic diversity changes in 480 European bread wheat varieties released from 1840 to 2000.

A sample of 480 bread wheat varieties originating from 15 European geographical areas and released from 1840 to 2000 were analysed with a set of 39 microsatellite markers. The total number of alleles ranged from 4 to 40, with an average of 16.4 alleles per locus. When seven successive periods of release were considered, the total number of alleles was quite stable until the 1960s, from which time it regularly decreased. Clustering analysis on Nei's distance matrix between these seven temporal groups showed a clear separation between groups of varieties registered before and after 1970. Analysis of qualitative variation over time in allelic composition of the accessions indicated that, on average, the more recent the European varieties, the more similar they were to each other. However, European accessions appear to be more differentiated as a function of their geographical origin than of their registration period. On average, western European countries (France, The Netherlands, Great Britain, Belgium) displayed a lower number of alleles than southeastern European countries (former Yugoslavia, Greece, Bulgaria, Romania, Hungary) and than the Mediterranean area (Italy, Spain and Portugal), which had a higher number. A hierarchical tree on Nei's distance matrix between the 15 geographical groups of accessions exhibited clear opposition between the geographical areas north and south of the arc formed by the Alps and the Carpathian mountains. These results suggest that diversity in European wheat accessions is not randomly distributed but can be explained both by temporal and geographical variation trends linked to breeding practices and agriculture policies in different countries.

Alleles↗
PubMed2003

Molecular diversity in French bread wheat accessions related to temporal trends and breeding programmes.

A set of 41 wheat microsatellite markers (WMS), giving 42 polymorphic loci (two loci on each chromosome), was used to describe genetic diversity in a sample of 559 French bread wheat accessions (landraces and registered varieties) cultivated between 1800 and 2000. A total of 609 alleles were detected. Allele number per locus ranged from 3 to 28, with a mean allele number of 14.5. On the average, about 72% of the total number of alleles were observed with a frequency of less than 5% and were considered to be rare alleles. WMS markers used showed different levels of gene diversity: the highest PIC value occurred in the B genome (0.686) compared to 0.641 and 0.659 for the A and D genomes, respectively. When comparing landraces with registered varieties gathered in seven temporal groups, a cluster analysis based on an F(st) matrix provided a clear separation of landraces from the seven variety groups, while a shift was observed between varieties registered before and after 1970. There was a decrease of about 25% in allelic richness between landraces and varieties. In contrast, when considering only registered varieties, changes in diversity related to temporal trends appeared more qualitative than quantitative, except at the end of the 1960s, when a bottleneck might have occurred. New varieties appear to be increasingly similar to each other in relation to allelic composition, while differences between landraces are more and more pronounced over time. Finally, considering a sub-sample of 193 varieties representative of breeding material selected during the twentieth century by the six most important plant breeding companies, few differences in diversity were observed between the different breeding programmes. The observed structure of diversity in French bread wheat collections is discussed in terms of consequences, both for plant breeders and for managers of crop genetic resources.

Alleles↗
PubMed2000

Prevalence and clinical significance of anti-phospholipid antibodies in multiple sclerosis: a study of 89 patients.

The prevalence of serum anti-phospholipid antibodies (aPL) was evaluated in multiple sclerosis (MS) patients to search for a possible association with a distinct form of the disease. Anti-cardiolipin antibodies (Ab) (aCL) and anti-beta 2 glycoprotein I Ab (abeta2GPI) were measured together with antinuclear Ab (ANA), anti-double-stranded DNA Ab (anti-ds DNA) and anti-myelin Ab in 89 patients. Twenty-nine (32.6%) patients had serum aPL, 19xaCL (15 of the IgG and four of the IgM isotype), 14 abeta2GPI (two IgG and 12 IgM) (four of these patients had both Ab). Prevalence of aCL correlated with that of ANA, which were positive in 52 patients (P=0. 005) and with anti-myelin Ab detected in two patients (P=0.046) but not with that of anti-ds DNA (mostly of the IgM class) detected in 28% of case by ELISA. No correlation could be found between aPL and age, sex, duration of the disease from diagnosis, category of MS, clinical course, clinical symptoms, serum IgM levels nor atypical lesions by magnetic resonance imaging. Hence, aCL and abeta2GPI are neither rare in MS nor associated with a specific clinical form of the disease and they cannot be a diagnosis exclusion criteria.

Adult↗
PubMed1998

Absence of anti-beta2 glycoprotein I antibodies in giant cell arteritis: a study of 45 biopsy-proven cases.

OBJECTIVE: To search for a relationship between serum anti-beta2 glycoprotein I (anti-beta2GPI) antibodies and the occurrence of ischaemic complications in giant cell arteritis (GCA), since the latter do not correlate with anti-cardiolipin antibodies (ACL), which are frequently observed in GCA. METHODS: IgG and IgM anti-beta2GPI antibodies and ACL were measured by enzyme-linked immunosorbent assays in sera, collected before treatment, from 45 unselected patients with biopsy-proven GCA, including 15 patients with ischaemic events. RESULTS: IgG and IgM anti-beta2GPI antibodies were not detected in any of the patients, contrasting with the presence of ACL in 51%, of them, without correlation with ischaemia. CONCLUSION: Anti-beta2GPI antibodies are not detectable in GCA, contrasting with the occurrence of ACL, and ischaemic complications are apparently unrelated to the most frequent anti-phospholipid antibodies.

Aged↗
PubMed1994

[Rhabdomyolysis in community-acquired pneumonia].

Several cases of rhabdomyolysis associated with pneumococcal pneumonia have been recently reported. However their significance have been poorly investigated. In this retrospective study, we have compared the patients admitted in ICU for acute community-acquired pneumonia with or without rhabdomyolysis (group A: CPK > or = 1,000 Ul/l and group B: CPK < 1,000 Ul/l). Among the 41 patients of the study, 12 (29%) belonged to the group A (CPK = 1,852 +/- 535 Ul/l) and 29 (71%) to group B (CPK = 190 +/- 35 Ul/l). Neither the initial severity, nor renal impairment were different in the two groups. However the mortality was significantly higher in the group A (4/12) than in group B (2/29) (P < 0.05). In this study, pneumonia is frequently associated with rhabdomyolysis, without etiologic significance. In patients with pneumonia, rhabdomyolysis seems to be a bad prognostic indice unrelated with renal impairment.

Adult↗