A total of 191 Campylobacterjejuni and 125 Campylobacter coli were isolated from the intestinal content of 398 chickens, 421 cattle, and 203 pigs. All 108 chicken isolates and 73 of 80 cattle isolates were C. jejuni, but 115 of the 118 pig isolates were C. coli. A total of 84% of the C. jejuni and 64% of the C. coli isolates were typed on the basis of thermostable antigens with 20 antisera prepared against frequently occurring serotypes in Campylobacter enteritis in man (15 C. jejuni, 6 C. coli serotypes). A total of 96% of the chicken isolates and 67% of the cattle isolates belonged to 11 C. jejuni serotypes that occur most frequently in human cases of enteritis (serotypes 1, 2, 3, 4, 5, 13/16, 18, 21, 23, 31, and 36). Serotype 8, a relatively common human isolate, was not recovered. The C. coli isolates from pigs belonged to serotypes uncommon among human isolates.

We have previously localized a locus causing familial nonspecific dementia to the centromeric region of chromosome 3 in a pedigree from the Jutland area of Denmark. This pedigree shows anticipation. Here we present further analysis of these anticipation data which are suggestive of trinucleotide repeat expansion involvement. We also outline our strategies to clone the mutant gene via its putative associated trinucleotide repeat sequence.

We have used a cDNA clone for human phosphoglycerate kinase (PGK) to examine the chromosomal localization of three members of the human PGK gene family. Using somatic cell hybrids segregating portions of several X-autosome translocations as well as a clone panel of hybrids segregating radiation-induced fragments of the human X chromosome, we assign a PGK pseudogene to the region Xq11-Xq13, proximal to the functional X-linked PGK gene located in Xq13. In addition, using a panel of 24 somatic cell hybrids, we assign an autosomal PGK-related DNA sequence to human chromosome 19.

We have created somatic cell hybrids between the temperature-sensitive mouse cell line tsA1S9 and human cell lines in order to localize the human gene (A1S9T) complementing the cell cycle defect of the murine line. Segregation of the human X chromosome is completely concordant with growth at the nonpermissive temperature. Hybrids retaining the X chromosome are temperature-resistant, whereas those without a human X are temperature-sensitive. Further hybrids made using human cell lines with X-autosome translocations indicate that the A1S9T gene is located on the short arm of the human X chromosome.

Serologically defined strains of Campylobacter jejuni and Campylobacter coli from healthy and diarrheic animals were examined for the occurrence of plasmid DNA in association with the antibiotic susceptibility of the bacterial host and the health status of the animal host. Of all campylobacter organisms surveyed, 53% (116 of 200) contained plasmid DNA. A plasmid occurrence rate of 73.8% was obtained for C. coli from healthy pigs, contrasted by lower plasmid occurrence rates for C. coli from diarrheic pigs (30%) and from all diarrheic animals (21.4%). For C. jejuni, in contrast, only 13.6% of healthy cattle contained plasmid DNA, contrasted by a higher plasmid occurrence rate of 31.2% from diarrheic cattle. A high plasmid occurrence rate of 75.8% was observed for C. jejuni from healthy chickens. Campylobacter plasmids ranged in size from '1 to 86 megadaltons. Antibiotic susceptibility for 52 animal isolates (excluding chickens) indicated that most isolates were susceptible to kanamycin, erythromycin, gentamicin, tetracycline, and compound sulfonamide, whereas few were susceptible to bacitracin (19.2%); approximately half were susceptible to ampicillin (55.8%) and streptomycin (51.9%), and no isolates were susceptible to penicillin G. More isolates containing plasmids were resistant to ampicillin, tetracycline, and gentamicin than were isolates not carrying plasmids, there being a statistically significant difference for tetracycline and gentamicin, which suggested that these two antibiotics were probably plasmid mediated. The antibiotic susceptibility patterns of 21 chicken isolates of C. jejuni, by contrast, were different in that most were susceptible to ampicillin in addition to kanamycin, erythromycin, and gentamicin, whereas few were susceptible to compound sulfonamide, streptomycin, and tetracycline in addition to penicillin G and bacitracin. A 30or 39-megadalton plasmid, or both, common to many of the chicken isolates was usually associated with tetracycline resistance. Campylobacter jejuni and to a lesser extent Campylobacter coli have been associated with both human and animal diseases, most commonly causing gastroenteritis (4, 5, 9, 17, 19, 25, 34). Campylobacter spp. now have been isolated from a wide range of hosts (34, 37, 42, 44), and it * Corresponding author. commonly are carried on plasmids, as are virulence properties such as attachment factors, toxin production, and invasiveness (11). Although C. jejuni and C. coli are known to carry plasmids (2, 7, 40, 41), no plasmid yet has been correlated to pathogenicity and only tetracycline resistance has been shown to be carried on a transferable 38megadalton (MDa) plasmid (40, 42). In this study, C. jejuni 339