Molecular analysis of V kappa III variable regions of polyclonal rheumatoid factors during rheumatoid arthritis

We report the first molecular characterization of V kappa regions of the main human autoantibodies occurring during rheumatoid arthritis, the polyclonal rheumatoid factors. Using two sets of polymerase chain reactions in order to amplify the cDNA derived from both peripheral blood and synovial fluid rheumatoid factor-secreting cells, nucleotide analysis of the V kappa III family usage shows the following: (a) at least three different V kappa III genes are used to encode polyclonal rheumatoid factors in a single patient, (b) each one of these genes seems more or less somatically mutated (from 1 to 14 mutations), (c) the mutation process preferentially affects the complementarity determining regions suggesting a selective pressure of antigen and (d) there is no clear difference between the mutation rates affecting the synovial fluid and peripheral blood rheumatoid factor-secreting cells. These results are able to explain some of the known idiotypic differences between monoclonal and polyclonal rheumatoid factors in humans. They also provide evidence that polyclonal autoantibodies arising during an autoimmune disease can be the products of multiple somatically mutated genes and suggest that this process is antigen driven, whether this antigen is the Fc piece of IgG or another unknown antigen.     

Investigations of red cell glyoxalase in recombinant families.

The polymorphism of the red cell glyoxalase (GLO), which has recently been found to be linked with the major histocompatibility complex (HLA) in man, was investigated in a number of selected families showing various recombinations between HLA-A, HLA-B and the third locus of the phosphoglucomutase (PGM3). In two families with a recombination between HLA-A and HLA-B, the GLO allele travels with the HLA-B locus fragment of the chromosome, indicating that GLO is located on the side of the HLA-B locus. In other families, recombinations occurred between HLA-A and B on one side and GLO and PGM3 on the other side, demonstrating that GLO and PGM3 are located on the same side of HLA. Other recombinations separated PGM3 from GLO so that it can be assumed that GLO is located between HLA-B and PGM3. Thus the immunogenetic linkage group on human chromosome C6 has been increased by yet another outside marker gene to include now the following genes in this order: HLA-A--HLA-C--HLA-B--Bf--HLA-D--GLO--PGM3.     

Initial evaluation of a continuous speech recognition program for radiology

The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.     

Extended treatment of primary osteoporosis by sodium fluoride combined with 25 hydroxycholecalciferol

Summary Nineteen patients suffering from primary osteoporosis, all having at least one vertebral collapse, initially received 50 mg of sodium fluoride alone per day for 6–18 months. Subsequently fluoride was associated with 25–50g of 25 OH cholecalciferol (calcifediol) per day for 6–18 months in 12 of these patients and 9 were treated for 31–58 months. As control group, 9 patients were given placebo for 6–18 months. The effect of the treatment was assessed by three methods: 1) the metacarpal index (MI) determined by radiogrammetry, 2) the calcium content of the hand bone (Ca) measured by local neutron activation, 3) the iliac bone histomorphometry. MI and (Ca) did not change significantly at any time in any group. In each group there was a significant increase in trabecular bone volume, osteoid volume, osteoid surfaces and a significant decrease in mineralization fronts. On the other hand, the changes in osteoblastic surfaces, osteoclastic surfaces, number of osteoclasts/mm2 were not significant in any group. No change was observed in the placebo group. These data suggest that the increase in the trabecular volume of fluorided bone is mainly due to the increase in osteoid which itself is due to a bone mineralization defect despite the association of calcifediol. This is probably one of the reasons why (Ca) does not change significantly.