Microsatellite markers for the grapevine pathogen, Eutypa lata.

We isolated and characterized nine polymorphic microsatellite markers for Eutypa lata, a fungal pathogen responsible for Eutypa dieback of grapevine, in populations from two California vineyards (24 isolates per vineyard). Allele frequency ranged from two to 11 alleles per locus and haploid gene diversity ranged from 0.33 to 0.83. All samples comprised unique haplotypes. Our results suggest that there is sufficient allelic polymorphism to estimate fine-scale spatial structure, and to identify possible sources of inoculum from habitats outside of vineyards.

Microsatellite markers for the diploid basidiomycete fungus Armillaria mellea.

We isolated and characterized 12 microsatellite markers for two North American populations (California, Pennsylvania) of Armillaria mellea, a fungal pathogen responsible for Armillaria root disease of numerous woody plants. Allele frequency ranged from two to nine alleles per locus, and gene diversity ranged from 0.05 to 0.86. Of the 12 loci, eight loci were polymorphic in the California and Pennsylvania populations, and showed no evidence of heterozygote deficiencies or severe linkage disequilibrium. Our results suggest that we have isolated and characterized variable loci to estimate genotypic diversity, gene flow and migration, and to determine population structure of North American A. mellea.

Tissue levels of bone resorptive cytokines in periodontal disease.

The levels of 3 bone resorptive cytokines, interleukin 1 alpha (IL-1 alpha), IL-1 beta, and tumor necrosis factor alpha (TNF alpha), were assessed in tissues from sites of periodontal disease. As determined by ELISA of tissue extracts, IL-1 beta and TNF alpha were detected in all diseased sites, whereas IL-1 alpha was present in 8/22 sites, IL-1 beta was present in highest concentration (mean +/- SEM: 11,695 +/- 2,888 pg/ml; 672 pM), followed by TNF alpha (434 +/- 135 pg/ml; 26 pM), and IL-1 alpha (342 +/- 160 pg/ml; 20 pM). The levels of all 3 mediators were significantly lower in clinically healthy tissues. There was a highly significant correlation between levels of IL-1 beta and TNF alpha (rs = 0.61, P less than 0.001), suggesting coordinated expression of these 2 mediators. The numbers of cells containing each mediator was also determined by indirect immunofluorescence on frozen tissue sections. Consistent with findings from tissue extracts, IL-1 beta-containing cells were present in approximately 5-fold higher numbers than TNF alpha-containing cells, and 40-fold higher numbers than IL-1-alpha-containing cells. Taken together with previous findings, these results indicate that IL-1 beta is likely to be an important mediator in the pathogenesis of periodontal disease.

Levels of interleukin 1 beta in tissue from sites of active periodontal disease.

Interleukin 1 beta is a potent bone resorptive cytokine which also mediates soft tissue destruction through the stimulation of prostaglandin production, and the induction of collagenase and other proteases. This constellation of activities suggests a role for IL-1 beta in the pathogenesis of human periodontitis. Levels of IL-1 beta were therefore determined in tissue obtained from (1) diseased, active (2) diseased, inactive and (3) healthy sites from 12 patients with destructive adult periodontitis. Disease activity was defined as attachment loss of greater than or equal to 2.5 mm, as determined by sequential probing and the tolerance method. IL-1 beta was extracted from homogenates of tissue biopsies taken at surgery, and levels were quantified by ELISA. IL-1 beta was found to be present in most patient tissue samples, with levels ranging from 0-82 ng/ml. Disease active sites had higher IL-1 beta levels (p less than 0.05) than inactive and healthy sites. Diseased inactive sites were divided into 2 groups, those losing small amounts of attachment (0.5-2.0 mm, worsening sites) and those which showed no change or attachment gain (stable sites). Stable diseased sites had IL-1 beta levels which were comparable to those found in healthy sites, and which were significantly different from active sites (p less than 0.02). Worsening sites had IL-1 beta levels intermediate between the levels in stable and active sites. Detection of disease activity occurred more frequently at sites with IL-1 beta levels greater than 25 ng/ml (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)