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B Ollier

Publications and source records attributed to B Ollier.

27 records · Page 2Linked to original sources
PubMed1993

HLA allele detection using molecular techniques.

There are now many molecular biological techniques available to define HLA class I and class II alleles. Some of these are also applicable to other human polymorphic genes, in particular to those non-HLA genes encoded within the Mhc. The range of techniques available allows laboratories to choose those most suited to their purpose. The routine laboratory supporting solid organ transplants will need to type large numbers of potential recipients over a period of time, probably using PCR-SSOP while donors will be typed singly and rapidly using PCR-SSP with HLA allele compatibility determined by heteroduplex analysis. Laboratories supporting bone marrow transplantation, where time is less pressing, can choose from the whole range of techniques to determine accurately donor recipient Mhc compatibility. For disease studies, techniques defining precise HLA allele sequence polymorphisms are needed and high sample numbers have to be accommodated. When an association is established allele sequencing has to be used. In the near future, the precise role of HLA alleles in transplantation and disease susceptibility is likely to be established unambiguously.

Alleles↗
PubMed1992

Incidence of rheumatoid arthritis in a genetically predisposed population.

A follow-up study (mean duration five years) was undertaken on 370 previously unaffected first degree relatives from multicase rheumatoid arthritis (RA) families. The objectives were to determine the incidence of RA in this group and the possible predictors of disease development. In all, 14 individuals developed RA, equivalent to an incidence of 8/1000 person-years of observation. There was no control group included in this study as the intensive-follow-up required substantial compliance from highly motivated families. Population-based estimates, however, from a number of sources would suggest an annual incidence below 0.5/1000 per year, substantially less than the rate obtained in this study. The small number of incident cases precluded definitive conclusions about risk factors within these families but there were no important effects of age or sex. Possession of HLA-DR1 or DR4 explained only some of the increased risk. The increased incidence observed in the previously unaffected relatives of such families would suggest that this familial clustering did not for the most part arise by chance and that other shared genetic or environmental influences are relevant.

Adolescent↗
PubMed1992

HLA heterozygosity contributes to susceptibility to rheumatoid arthritis.

We have investigated the role of HLA-DR genotypes in 184 patients with severe rheumatoid arthritis (RA) and in 46 patients with Felty syndrome, to establish the relative contribution of the RA-associated subtypes of DR4 (Dw4, Dw14, and Dw15). There was an excess of DR4 homozygotes, particularly Dw4/Dw14 compound heterozygotes (relative risk [RR] 49). The risk associated with Dw4 depended on the other allele present--Dw4/DR1 (RR 21), Dw4/Dw4 (RR 15), and Dw4/DRX (RR 6). There was a significant risk from Dw4/Dw14 compared with Dw4/Dw4, both in those with severe RA (RR 2.9; P less than .02) and in those with Felty syndrome (RR 4.2; P less than .02). In contrast, in a further 63 known DR4 homozygotes with RA, not selected for severe disease, the excess of Dw4/Dw14 was much less striking (RR 1.4; not significant), suggesting that this genotype may be particularly associated with more severe disease. We also found four cases with the rare Dw4/Dw15 genotype (expected less than or equal to 0.5; P less than or equal to .02). Since the Dw4, Dw14, Dw15, and DR1 molecules have similar antigen-binding sites and since combinations of these alleles particularly predispose to severe RA, we suggest that synergistic mechanisms are involved. These could include an effect on T-cell repertoire selection.

Alleles↗
PubMed1991

Rheumatoid factor detection in the unaffected first degree relatives in families with multicase rheumatoid arthritis.

Rheumatoid factor (RF) was assayed in 354 unaffected first degree relatives from 59 families with multicase rheumatoid arthritis (RA), using both the latex test and ELISA for different RF isotypes. The association between HLA and presence of RF was also analyzed. In all, 39% of the relatives were positive for at least one class of RF compared to 7% positive for latex. There were no differences between the sexes in these rates. There were significant excess rates of HLA-DR4 in RF positive when compared to the RF negative relatives. The HLA-DR4 frequency in these RF positive RA negative individuals is similar to that observed in series of RA positive patients. Thus HLA status did not usefully discriminate between RA positive and RA negative but RF positive individuals in these families.

Arthritis, Rheumatoid↗
PubMed1988

HLA: linkage with rheumatoid arthritis or seropositivity.

HLA haplotype sharing was compared in sibships from multicase families with rheumatoid arthritis (RA), subdivided by rheumatoid factor status, to investigate the claim that HLA is linked more to RA severity than susceptibility. Considerable deviation from expected (Mendelian) inheritance towards greater sharing of inherited parental haplotypes was observed in the sibships as a whole and when subdivided according to the serological status of the sibship's members. Further, there was no evidence that linkage was stronger in the seropositive concordant than in the other sibships. Linkage was also demonstrated between HLA and seropositivity even in sibships where not all members expressed clinical RA. These results, therefore, do not support the existence of genetic heterogeneity between seropositive and seronegative RA, a possibility previously suggested from population studies of antigen associations.

Antibodies↗
PubMedDate not supplied

[A custom grooved impression tray].

Individual compartment trays can be used for dental impression in fixed prosthodontics and represent an original method which alleviates the pitfalls of standard technics. This method is based upon a strict adaptation of the tray to both the preparations and the dental arcade using the primary impression. Impression pastes can be used in their optimal conditions using the I.C.T. (Individual Compartment Trays) and a higher definition of cervical limits can be obtained. The use of I.C.T. reduces the risks of interposing free marginal gingival and eliminates the inconvenients of intrasulcular leakage.

Dental Impression Technique↗