All issues
Successor
Volume 43 (2001)
- Issue 6 Pages 653-
- Issue 4 Pages 343-
- Issue 3 Pages 229-
- Issue 2 Pages 105-
- Issue 1 Pages 1-
Predecessor
Volume 43, Issue 6
Displaying 1-6 of 6 articles from this issue
- |<
- <
- 1
- >
- >|
-
Ki-ichiro Tanaka, Toshio Ono, Takeshi Kobayakawa2001 Volume 43 Issue 6 Pages 653-658
Published: December 20, 2001
Released on J-STAGE: June 11, 2010
JOURNAL FREE ACCESSWhen a rat tail tendon swollen after incubation in guanidine hydrochloride was soaked in an artificial calcification solution, its calcification was promoted. X-ray small angle scattering of the tendon suggested the formation of cracks in the tendon collagen. The cracks may provide the location and sites for nucleations of calcium phosphate crystals. Decorin, a powerful inhibitor of calcification, is eluted out by the guanidine hydrochloride treatment.View full abstractDownload PDF (2232K) -
Tomokazu Nakajima, Ryuichi Fujisawa, Yoshinori Kuboki2001 Volume 43 Issue 6 Pages 659-665
Published: December 20, 2001
Released on J-STAGE: June 11, 2010
JOURNAL FREE ACCESSPhosphophoryn (PP) is a unique phosphoprotein of dentin. Previous investigators have reported that PP degrades during tooth maturation, but its degradation mechanism has not been determined. In this study, we attempted to examine the susceptibility of PP to proteases, using SDS-PAGE with sensitive staining, and we discussed the mechanisms of PP degradation. A human molar, divided into crown and root, was analyzed by SDS-PAGE. The crown fragment contained more lower molecular weight components than the root fragment, indicating that human PP is degraded in vivo during maturation. To examine the mechanisms of the degradation, we investigated the susceptibility of PP to proteases and heat treatment. Rat PP preparations were subjected to matrix metalloproteinase-2 (MMP-2), trypsin or heat treatment. Major bands of rat PP were observed at 74 and 70kDa. These two bands were clearly observed in the sample treated with MMP-2 or trypsin, but in the heat-treated sample, the proteins corresponding to the major bands were degraded and only diffuse staining was observed. Enzymatic PP degradation was not observed for MMP-2 and trypsin. The non-enzymatic degradation, such as β elimination, as well as enzymatic processes by other MMPs, might contribute to PP degradation.View full abstractDownload PDF (2265K) -
Hiroshi Inokuchi, Masako Mizuno-Kamiya, Atsushi Fujita2001 Volume 43 Issue 6 Pages 666-675
Published: December 20, 2001
Released on J-STAGE: June 11, 2010
JOURNAL FREE ACCESSThe enzymatic characteristics of Ca2+-independent phospholipase A2 activities in an apical enriched plasma membrane fraction (A-PM) were compared with those in a secretory granular fraction (SG) from the rat parotid gland: They showed similar substrate specificities. Both enzymes preferred neutral phospholipids such as phosphatidylcholine and phosphatidylethanolamine to acidic ones. 1, 2-Diacyl-sn-glycero-3-phosphocholine was a better substrate for both enzymes than 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholine although the two enzymes hardly distinguished the fatty acyl species at the sn-1 position. A similar specificity was also observed even when two kinds of substrates were present in mixed micelles. The various well-documented inhibitors of phospholipase A2s, arachidonyl trifluoromethyl ketone, methyl arachidonyl fluorophosphate and dithiothreitol, did not inhibit the phospholipase A2 activities in A-PM and SG. These findings indicated that the two Ca2+-independent phospholipase A2s in A-PM and in SG had similar biological properties, suggesting that they may belong to the same group.View full abstractDownload PDF (2219K) -
New Findings on Acinar Atrophy and RegenerationHideo Yagishita, Minoru Uchida, Shigeo Aiyama2001 Volume 43 Issue 6 Pages 676-689
Published: December 20, 2001
Released on J-STAGE: June 11, 2010
JOURNAL FREE ACCESSThe present study was conducted to clarify the histological changes in the acinar and myoepithelial cells of the rat submandibular gland after ligation of the main excretory duct for one week, and also the regenerative movements of these cells after ligation release. Tissue specimens were subjected to immunostaining and TUNEL staining, and examined by light microscopy. Some of the samples were prepared for transmission electron microscopy by a routine method. Duct-like structures covered with myoepithelial cells were not detected in normal rats, but were frequently observed after ligation of the main excretory duct. A few TUNEL-positive acinar cells, apparently apoptotic, were observed by light microscopy, but could not be identified by electron microscopy. Therefore, we consider that only a limited number of cells underwent apoptosis, if any. Almost normal acinar cells were detected throughout the entire submandibular gland 4 weeks after the loosening of the ligature. These findings suggest that duct-like structures may become acini, resulting in recovery.View full abstractDownload PDF (7584K) -
Kazuyuki Saito, Yoshinobu Asada2001 Volume 43 Issue 6 Pages 690-699
Published: December 20, 2001
Released on J-STAGE: June 11, 2010
JOURNAL FREE ACCESSThe purpose of this study was to identify the major candidate chromosome and to detect the region that included the candidate gene (s) causing absence of the third molars in EL/sea mice. The candidate chromosomal analysis was performed on genetic crosses using two strains of mice, EL with absence of the third molars, and DDY with a normal complement of teeth. Linkage analysis by interval mapping with microsatellite markers suggested that mouse chromosome 13 was one of the candidate chromosomes and therefore this chromosome was investigated in detail by individual genotyping of F 2 intercross mice with missing third molars. The highest scores were found at D13Mit78 and D13Mit35 markers (xx2=11.8, p< 0.01). Based on these findings, it is suggested that the gene causing absent third molars in EL mice maps close to these microsatellite loci.View full abstractDownload PDF (1635K) -
Atsuko Igarashi, Mitsunori Monya, Shuichi Nomura2001 Volume 43 Issue 6 Pages 700-703
Published: December 20, 2001
Released on J-STAGE: June 11, 2010
JOURNAL FREE ACCESSDownload PDF (665K)
- |<
- <
- 1
- >
- >|