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Bunching onion (Allium fistulosum L.; 2n = 16), bulb onion (Allium cepa L. Common onion group), and shallot (Allium cepa L. Aggregatum group) cultivars were inoculated with rust fungus, Puccinia allii, isolated from bunching onion. Bulb onions and shallots are highly resistant to rust, suggesting they would serve as useful resources for breeding rust resistant bunching onions. To identify the A cepa chromosome(s) related to rust resistance, a complete set of eight A. fistulosum--shallot monosomic alien addition lines (MAALs) were inoculated with P. allii. At the seedling stage, FF+1A showed a high level of resistance in controlled-environment experiments, suggesting that the genes related to rust resistance could be located on shallot chromosome 1A. While MAAL, multichromosome addition line, and hypoallotriploid adult plants did not exhibit strong resistance to rust. In contrast to the high resistance of shallot, the addition line FF+1A+5A showed reproducibly high levels of rust resistance. Key words: Allium fistulosum, Allium cepa, bunching onion, shallot, rust resistance, monosomic addition lines. Des cultivars de la ciboule (Allium fistulosum L.; 2n = 16), de l'oignon (Allium cepa L. groupe de l'oignon commun) et de l'echalote (Allium cepa L. groupe Aggregatum) ont ete inocules avec le champignon qui cause la rouille, Puccinia allii, isole a partir de la ciboule. Les oignons et les echalotes etaient tres resistants a la rouille, ce qui suggere qu'ils pourraient servir de source de resistance pour developper des ciboules resistantes a la rouille. Afin d'identifier le(s) chromosome(s) de l'A. cepa portant la resistance a la rouille, un jeu complet de huit lignees d'addition monosomiques (MAAL) A fistulosum - echalote ont ete inoculees avec le P. allii. Au stade plantule, la lignee FF+1A a affiche une grande resistance lors d'inoculations en conditions controlees, ce qui suggere que les genes conferant la resistance a la rouille seraient situes sur le chromosome 1A de l'echalote. Contrairement a la grande resistance presente chez l'echalote, les plantes adultes des MAAL, des lignees d'additions chromosomiques multiples ou hypoallotriploides n'affichaient pas une grande resistance a la rouille. Seule une lignee d'addition FF+1A+5A affichait une grande resistance a la rouille de maniere reproductible. [Traduit par la Redaction] Mots-cles : Allium fistulosum, Allium cepa, ciboule, echalote, esistance a la rouille, lignees d'addition monosomiques., Introduction In Japan, bunching onion (Allium fistulosum L.) is one of the most important vegetable crops and has the highest annual output (134 billion yen) of all Allium crops (Ministry [...]

The ability of opaque porcelain to conceal the color of noble alloy or nickel-chromium substructures was compared. A 0.5-mm layer of opaque porcelain was fused to the sample metals and chromatic analyses were carried out with a color analyzer. Color measurements were made as the thickness of porcelain was reduced in 0.1-mm increments. The true color of the opaque porcelain was apparent in ceramic thicknesses greater than 0.3 mm. The opaque porcelain was more efficient at covering noble alloys than nickel-chromium alloys. [ABSTRACT FROM AUTHOR]

This paper describes the utility of three-dimensional (3D) images obtained with cone beam computed tomography (CBCT) for prediction of successful clinical outcome in two cases of intentional tooth replantation (IR). IR was performed for teeth affected by vertical root fracture and root perforation with local application of blood clot and oxy-tetracycline antibiotic. High-resolution 3D images demonstrated no evidence of ankylosis, but did reveal the presence of alveolar bone regeneration, suggesting a good long-term prognosis. Our observations in these cases suggested that local application of the above two materials might help to induce the regeneration of lost periodontal tissues in IR. [ABSTRACT FROM AUTHOR]

Raphanus sativus (2n = 2x = 18) is a widely cultivated member of the family Brassicaceae, for which genomic resources are available only to a limited extent in comparison to many other members of the family. To promote more genetic and genomic studies and to enhance breeding programmes of R. sativus, we have prepared genetic resources such as complementary DNA libraries, expressed sequences tags (ESTs), simple sequence repeat (SSR) markers and a genetic linkage map. A total of 26 606 ESTs have been collected from seedlings, roots, leaves, and flowers, and clustered into 10 381 unigenes. Similarities were observed between the expression patterns of transcripts from R. sativus and those from representative members of the genera Arabidopsis and Brassica, indicating their functional relatedness. The EST sequence data were used to design 3800 SSR markers and consequently 630 polymorphic SSR loci and 213 reported marker loci have been mapped onto nine linkage groups, covering 1129.2 cM with an average distance of 1.3 cM between loci. Comparison of the mapped EST-SSR marker positions in R. sativus with the genome sequence of A. thaliana indicated that the Brassicaceae members have evolved from a common ancestor. It appears that genomic fragments corresponding to those of A. thaliana have been doubled and tripled in R. sativus. The genetic map developed here is expected to provide a standard map for the genetics, genomics, and molecular breeding of R. sativus as well as of related species. The resources are available at http://marker.kazusa.or.jp/Daikon. [ABSTRACT FROM PUBLISHER]

Background: Protogenin (Prtg) has been identified as a gene which is highly expressed in the mouse mandible at embryonic day 10.5 (E10.5) by a cDNA subtraction method between mandibles at E10.5 and E12.0. Prtg is a new member of the deleted in colorectal carcinoma (DCC) family, which is composed of DCC, Neogenin, Punc and Nope. Although these members play an important role in the development of the embryonic central nervous system, recent research has also shed on the non-neuronal organization. However, very little is known regarding the fetal requirement of the non-neuronal organization for Prtg and how this may be associated with the tooth germ development. This study examined the functional implications of Prtg in the developing tooth germ of the mouse lower first molar. Results: Ptrg is preferentially expressed in the early stage of organogenesis. Prtg mRNA and protein were widely expressed in the mesenchymal cells in the mandible at E10.5. The oral epithelial cells were also positive for Prtg. The expression intensity of Prtg after E12.0 was markedly reduced in the mesenchymal cells of the mandible, and was restricted to the area where the tooth bud was likely to be formed. Signals were also observed in the epithelial cells of the tooth germ. Weak signals were observed in the inner enamel epithelial cells at E16.0 and E18.0. An inhibition assay using a hemagglutinating virus of Japan-liposome containing Prtg antisensephosphorothioated- oligodeoxynucleotide (AS-S-ODN) in cultured mandibles at E10.5 showed a significant growth inhibition in the tooth germ. The relationship between Prtg and the odontogenesis-related genes was examined in mouse E10.5 mandible, and we verified that the Bmp-4 expression had significantly been decreased in the mouse E10.5 mandible 24 hr after treatment with Prtg AS-S-ODN. Conclusion: These results indicated that the Prtg might be related to the initial morphogenesis of the tooth germ leading to the differentiation of the inner enamel epithelial cells in the mouse lower first molar. A better understanding of the Prtg function might thus play a critical role in revealing a precious mechanism in tooth germ development. [ABSTRACT FROM AUTHOR]

Background: Age-dependent morphological and cell kinetic changes of the gingival tissue seem lo be related to the occurrence of periodontal disease. The purpose of this study was to investigate the age-dependent changes in the distribution of BrdU- and TUNEL-positive cells in murine gingival tissue. Methods: Gingival tissue of the lower first molar region of 2-, 3-, 5-, 7-, 10-, 15-, 20-, 30-, 40-, 50-, 50-, 70- and 80-week-old mice was used in this study. BrdU- and TUNEL-positive cells were evaluated at the following 4 sites: 1) gingival epithelium (GE); 2) junctional epithelium (JE); 3) submucosal connective tissue of the gingival epithelium (GECT); and 4) submucosal connective tissue of the junctional epithelium (JECT). Results: No significant differences in the mean number of BrdU-positive cells at each site were demonstrated among the various age groups. No significant change in the mean number of TUNEL-positive cells was demonstrated in either the GE or JE groups among the various age groups. Meanwhile, a significant increase in the TUNEL-positive cells was observed in the GECT of mice 40 weeks or older, and in the JECT of mice 20 weeks or older. Conclusions: These results indicate that no age-dependent change in the cell proliferation or cell death occurred in the gingival and junctional epithelial layers as well as in the cell proliferation in the submucosal connective tissue. Meanwhile, a significant decrease in the cellular component of the submucosal connective tissue of both gingival and junctional epithelial layers caused by apoptosis occurred with aging. The decreased cellular component in the submucosal connective tissue thus seems to be related to either gingival recession or to the apical migration of the JE with aging. These morphological changes with aging possibly occur in humans and may be related to the susceptibility to periodontal disease in aged individuals. [ABSTRACT FROM AUTHOR]

Several growth factors have been used in tissue regeneration therapy. Here we describe the use of an autologous blood clot combined with gelatin for teeth affected by severe periodontitis and vertical root fracture treated using three oral surgical procedures: periodontal flap surgery, intentional tooth replantation (IR), and tooth autotransplantation. Treatment with a blood clot improved the condition of the periodontal tissue, including reduction of pocket depth. Radiographical images demonstrated no evidence of ankylosis, and revealed the presence of alveolar bone regeneration. Our successful clinical outcome suggests that use of an autologous blood clot combined with gelatin is clinically effective for regeneration of lost periodontal tissue.

Periodontal tissue deteriorates under persistent oxidative stress induced by inflammatory reactions in the microflora of the oral cavity. This study aimed to evaluate the cellular properties of mouse gingival fibroblasts (MGFs) in the presence of oxidative stress. MGFs from 10-, 30- and 52-week-old mice were used to evaluate the changes in the cellular properties with aging. The study investigated the effects of oxidative stress on the cellular properties of MGFs from 10-week-old mice. The expression of p53, p21 and murine double minute 2 (Mdm2) in the MGFs in response to oxidative stress was also examined. By day 8, the number of MGFs increased in culture. However, the increase was markedly lower in MGFs derived from aged mice. Oxidative stress due to hydrogen peroxide (H2O2)-induced morphological changes characterized by a round shape with enlarged nuclei and expanded cytoplasm. The cell number of MGFs was decreased subsequent to treatment with 50 µM or a higher concentration of H₂O₂. MGFs treated with H₂O₂ at 20 µM showed a similar cell growth curve as the one seen in 52-week-old mice. Phosphorylated p53 protein was increased in MGFs subsequent to treatment with 20 µM H2O2, along with an upregulated transcription of p21 and Mdm2 mRNAs. These results suggest that treatment with a lower concentration of H₂O₂ in MGFs induces cell cycle arrest, resulting in stress-induced premature senescence, possibly correlated with the development of periodontal diseases.

This study examined the antimicrobial/antifungal ability of a tissue conditioner containing a photocatalyst for Escherichia coli, Streptococcus mutans, Staphylococcus aureus and Candida albicans. The photocatalyst was mixed with tissue conditioners powders at concentrations of 0, 10, 15, and 20 wt%. Tissue conditioners powders containing a photocatalyst were mixed with liquid to make test specimens. Test specimens inoculated by each microorganism were irradiated by ultraviolet light for 0-, 2- and 4 hours. The antimicrobial/antifungal effects were evaluated by the CFU technique. The CFU values of each microorganism for tissue conditioners containing a photocatalyst showed significant decrease following UV-irradiation. The improvement in antimicrobial/antifungal effects was concomitant with the increase of the mixing ratio and the irradiation time. Therefore, the results indicated that tissue conditioners containing a photocatalyst might have photocatalytic ability.

This study examined the ability of a photocatalyst mixed in a denture base resin to decompose organic substances which adhered to the denture base resin surface. The photocatalyst was mixed with denture base resin at concentrations of 0, 5, 10, and 15% (w/w). Decomposition test, bending test, and surface roughness measurement were performed at 1, 7, 30, 90, and 180 days after polymerization. Decomposition ability was evaluated based on the residual amount of methylene blue (MB) dissolved in ethanol after UV irradiation for 12 hours. As the mixing ratio increased, the amount of MB in the solution decreased. Meanwhile, no changes in the amount of MB in the immersion solution were observed in the photocatalyst-free resin specimen. Therefore, the results indicated that a denture base resin containing a photocatalyst might have a photocatalytic ability.