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Notes: Although data on chemical properties of Achillea species are numerous, morphological studies are rare. Therefore, during 1995-97, some morphological and production biological characters (height, width, number of stems, dry flower mass and leaf colour) of Achillea crithmifolia, their stability over years and generations, their dependence upon plant age and their correlations with the accumulation of essential oil were examined. The populations investigated were raised from seed materials stored in the genebank of the Department.The considerable diversity of the populations indicated a high degree of heterozygosity of these traits in natural stands. Variability was highest in number of stems (15.3-37.4 pieces) and essential oil content (0.63-1.27%). This variability did not disappear during three successive generations of inbreeding, although a decrease in variance was observed. Essential oil content was shown to have a higher heritability than other properties. Correlations of plant height, width and number of shoots were medium (r = 0.539-0.757), and their correlation with the essential oil content was also significant. Both the year of examination and age of the plants exerted a strong influence on most of the characters studied.

Notes: In harmony with international regulations the creation of poppy cultivars with high alkaloid content as well as free of alkaloids is in progress. In the course of selection procedures, five poppy cultivars of high chemical diversity, ‘Kheops’, ‘AT, ‘Tebona’, ‘Kék Gemona’ and ‘Przemko’, were selfed and crossed in two successive years (2000-01). After full ripening, both the biomass production and the alkaloid content of capsules of selfed and crossed plants were determined. When the castrated alkaloid-free cultivar ‘Przemko’ (accumulating only 0.01 mg/100 g morphine in capsules) was pollinated with cultivars rich in alkaloids, the morphine content of its capsules increased to 0.9-7.5 mg/100 g-values. Based on the well-known biosynthetic background of poppy alkaloids, this can be explained by promotion of (S)-norcoclaurine synthesis, which seems to be suppressed in alkaloid-free plants; but tissues of the developing hybrid seeds, which contain a combined gene pool of both alkaloid-free cultivar and that of the pollen donor plants, release this suppression. The chemical metaxenia also manifested itself in other combinations. In particular, the appearance of narcotine (0.1-1.1 mg/100 g) in the narcotine-free cultivars ‘Kheops’, ‘A1’ and ‘Przemko’ can be explained biochemically. If the narcotine-type plants ‘Kék Gemona’ (accumulating 11.3 mg/g narcotine) were used for pollination, the developing seed tissue, which contains the gene pool of narcotine biosynthesis, might contribute to the suppression of the activity of 1,2-dehydroreticuline reductase, which leads to the accumulation of narcotine at the cost of morphinanes.

Notes: We have studied the relationship between perturbations of fibroblast turnover in inflamed gingiva of different severities. To perform detailed spatial analyses of gingival fibroblast progenitor cells, inflammatory cell infiltrates and blood vessels, 3 Cynomolgus monkeys with healthy periodontium and 2 with naturally occurring gingivitis and ligature-induced periodontitis were pulse-labeled with 3H-thymidine. Morphometric analyses of radioautographs from mid-sagittal supra-alveolar gingival connective tissues of incisors were performed in sites subjacent to junctional, sulcular and oral epithelium, in the body of the lamina propria and just superior to the alveolar crest. The percentage of fibroblasts incorporating 3H-thymidine label, expressed as the labeling index (LI), was higher subjacent to the sulcular epithelium in periodontitis (1.73±0.37) than in healthy sites (1.06±0.22). This was not statistically significant (0.05 〈 p 〈 0.1) due to the small number of animals used. The sites subjacent to the sulcular epithelium also exhibited the largest increase in lymphocyte density from health to gingivitis (p 〈 0.01). In contrast, the LI of fibroblasts subjacent to the oral epithelium was 5-fold higher in healthy (0.82±0.17) compared to periodontitis sites (0.13 ± 0.09; p 〈 0.05). Labeled fibroblasts were found close to blood vessels in all compartments and in all disease states; distance to blood vessels was reduced in inflamed sites (p 〈 0.10). There were increased numbers of blood vessels per unit area in the lamina propria of gingivitis compared to healthy sites. However, there were no regional differences with respect to blood vessel numbers or area in sites subjacent to junctional epithelium with different disease states. The results indicate that: 1) experimentally-induced inflammation in the gingiva of Cynomolgus monkeys is associated with site-specific perturbations of cell turnover; 2) fibroblast progenitors are preferentially situated adjacent to blood vessels as in the periodontal ligament; 3) the vascular response to inflammation is a generalized increase in blood vessel numbers, but not their size; 4) reactive proliferation of fibroblasts may compensate for cell death in the lamina propria but is not detectable at the site of connective tissue attachment loss subjacent to the junctional epithelium. Failure to maintain the fibroblast progenitor population may be an important component of attachment loss in progressive periodontitis lesions.

Notes: Cells obtained from calvariae of fetal rats, human gingival connective tissue and periodontal ligament of rat molars were each co-cultured in vitro with non-demineralized and partly demineralized root slices in nutrient medium containing 50 μGg/ml ascorbic acid and 10 mM B-glyeerophosphate, in order to determine whether the root slices could affect the phenotype expressed by the cells. The cultures were examined by light and transmission electron microscopy. Nodules of bone-like tissue, resembling those previously described by others, were observed in the multilayers of cells obtained from rat calvariae. but not in the multilayers of gingival and periodontal ligament cells, after 30 days of culture. Calvaria cells associated with the root slices produced tissues exhibiting ultrastructure that resembled that of bone or cellular cementum. acellular cemenlum and afibrillar cementum in vivo when examined after the same length of time. The tissues were never found in cultures of gingival fibroblasts or periodontal ligament cells. These observations suggest, first, that cells derived from bone can express in vitro the phenotype for the cementums; second, that cells obtained from human gingival and rat periodontal ligament do not do so when cultured under similar conditions; and third, the possibility that the osteoblasts, cementoblasts and their progenitors that are found in the periodontal ligament could, at least in part, have their origin and migrate there from the endosteal spaces of the alveolar process.