RÉSUMÉ
Abstract Brachychiton populneus (Schott & Endl.) R.Br., Malvaceae, is one of five Brachychiton species cultivated in Egypt. Little information was found concerning the morphological, phytochemical and biological investigations of B. populneus. Morphological investigations of B. populneus were performed on fresh and dried leaves. Air-dried, ground leafy branches were extracted with 70% methanol/water yielding B. populneus extract. Seventeen flavonoids were isolated and identified using different chromatographic and spectroscopic techniques; eleven of them were reported for the first time from this plant. Potential activity of B. populneus extract against alloxan inducing oxidative stress and diabetes in male rats was preliminary investigated (four groups of ten rats /group). B. populneus extract (500 mg/kg bw i.p.) exhibited significant acute anti-hyperglycemic activity with blood glucose levels of 227.3 and 157.6 mg/dl after 4 and 24 h, respectively, compared to alloxan and standard Diamicron (5 mg/kg bw p.o.) groups, as well as to a normoglycemic control group at p < 0.05. The extract reverted the body weight values of the alloxan-induced diabetic rats to that of control animals after 24 h. In addition, B. populneus extract counteracted the effect of the oxidative stress induced by alloxan causing significantly increase in the glutathione content level (2.35 mmol/l) and relative decrease in the malondialdehyde level (21.31 nmol/l) and nitric oxide content (1.98 µmol/l) in serum after 24 h of treatment compared to alloxan-induced diabetic rats (1.01 mmol/l, 118.9 nmol/l, 4.69 µmol/l, respectively) and to normoglycemic control at p < 0.05. These effects appear to be related to the flavonoid principles. The intergeneric relationship of the genus Brachychiton and other related genera assessed well-supported differentiation between them. Furthermore, a significant dissimilarity was observed at interspecific level.
RÉSUMÉ
Complete understanding of the exterior and interior structure of the tooth would be prerequisite to the successful clinical results, especially in the restorative and endodontic treatment. Although three-dimensional reconstruction method using x-ray microtomography could not be used in clinical cases, it may be the best way to reconstruct the morphologic characteristics of the tooth structure in detail without destructing the tooth itself. This study was done to three dimensionally reconstruct every teeth in the arch in order to increase the understanding about the endodontic treatment and to promote the effective restorative treatment by upgrading the knowledge of the tooth morphology. After placing tooth between the microfocus x-ray tube and the image intensifier to obtain two-dimensional images of each level, scanning was done under the condition of 80 keV, 100 microA, 16.8 magnification with the spot size of 8 microm. Cross-section pixel size of 16.28 microm and 48.83 cross-section to cross-section distance were also used. From the results of this study, precise three dimensional reconstructed images of every teeth could be obtained. Furthermore, it was possible to see image that showed interested area only, for example, enamel portion only, pulp and dentin area without enamel structure, pulp only, combination image of enamel and pulp, etc. It was also possible to see transparent image without some part of tooth structure. This image might be used as a guide when restoring and preparing the full and partial crown by showing the positional and morphological relationship between the pulp and the outer tooth structure. Another profit may be related with the fact that it would promote the understanding of the interior structure by making observation of the auto-rotating image of .AVI file from the various direction possible.