CTSK distribution in the developing molars of mouse at E18 and P1.

<p>Immunopositive staining for CTSK is not detectable in the second molar germ <b>(A)</b>, or the first molar germ <b>(B)</b> at E18. <b>(C)</b> Higher magnification of the frame in <b>(B)</b>. Immunopositive staining for CTSK couldn’t be detected in the second molar germ <b>(D)</b> at P1. However, weak staining could be observed in the first molar germ <b>(E)</b> at P1. <b>(F)</b> Higher magnification of the frame in <b>(E)</b>. Abbreviations: de, dentin; df, dental follicle; dp, dental papilla; iee, inner enamel epithelium; oee, outer enamel epithelium; Pre-am, pre-ameloblasts; sr, stellate reticulum.</p

The role of CTSK in degrading enamel matrix protein.

<p>(A) Emdogain zymograms of CTSK. Areas of proteolysis appear as clear regions within the gel. Lane 1, marker; lane 2–6, the gels were immersed for 2, 6, 12, 24, 48 hrs respectively in the incubation buffer at 37°C. (B) Digestion of AMELX (2 μg) by CTSK (0.15 μg). Lane 1, marker; lane 2, standard aliquots of AMELX; lane 3, standard aliquots of AMELX incubated without CTSK at 37°C for 24 hrs; lane 4–10, digestion of AMELX by CTSK for 0, 2, 4, 8, 12, 24 and 48 hrs respectivelyat 37°C in the incubation buffer; lane 11, standard aliquots of CTSK. (C) Digestion of AMELX (2 μg) by CTSK (0.025 μg). Lane 1, marker; lane 2, standard aliquots of AMELX; lane 3, standard aliquots of AMELX incubated without CTSK at 37°C for 24 hrs; lane 4–11, digestion of AMELX by CTSK for 0, 2, 4, 8, 12, 24, 36 and 48 hrs at 37°C in incubation buffer, respectively.</p

Comparison of the matrix composition in fourkinds of mineralized tissues.

<p>Comparison of the matrix composition in fourkinds of mineralized tissues.</p

Comparison between ruffle-ended ameloblasts and osteoclasts(summarized according to the description in Smith, 1998).

<p>Comparison between ruffle-ended ameloblasts and osteoclasts(summarized according to the description in Smith, 1998).</p

Diterpene Alkaloids with an Aza-<i>ent</i>-kaurane Skeleton from <i>Isodon rubescens</i>

Two compounds belonging to a new group of diterpene alkaloids, kaurines A and B (<b>1</b> and <b>2</b>), and an alkaloid bearing a succinimide moiety (<b>3</b>) were obtained from <i>Isodon rubescens</i>. Their structures and absolute configurations were determined by spectroscopy and quantum-chemical computational ¹³C NMR and ECD data analysis. These alkaloids differ from known diterpene alkaloids and diterpenoids and are presumably biosynthesized from <i>ent</i>-kaurane diterpenoids

Bioactive Enmein-Type <i>ent</i>-Kaurane Diterpenoids from <i>Isodon phyllostachys</i>

Thirty-two enmein-type <i>ent</i>-kaurane diterpenoids, including 13 new compounds, were isolated from the aerial parts of <i>Isodon phyllostachys</i>. Compounds <b>1</b> and <b>2</b> are the first examples of 3,20:6,20-diepoxyenmein-type <i>ent</i>-kauranoids, and the structures of these new compounds were established mainly by analyzing NMR and HREIMS data. The absolute configurations of <b>1</b> and <b>8</b> and the relative configuration of <b>9</b> were determined using single-crystal X-ray diffraction. Compounds <b>11</b>, <b>15</b>, <b>20</b>, and <b>21</b> were active against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480), with IC₅₀ values ranging from 1.2 to 5.0 μM. Compounds <b>3</b>, <b>11</b>, <b>15</b>, <b>17</b>, <b>20</b>, <b>21</b>, <b>25</b>, and <b>29</b> strongly inhibited NO production in LPS-stimulated RAW264.7 cells, with IC₅₀ values ranging from 0.74 to 4.93 μM

Structural Characterization of Kadcoccinin A: A Sesquiterpenoid with a Tricyclo[4.4.0.0^3,10]decane Scaffold from <i>Kadsura coccinea</i>

Kadcoccinin A (<b>1</b>), a cage-like sesquiterpenoid possessing a tricyclo­[4.4.0.0^3,10]­decane scaffold, and the biosynthetically related kadcoccinin B (<b>2</b>) were isolated from the stems of <i>Kadsura coccinea</i>. Their structures and absolute configurations were determined from extensive spectroscopic analysis and quantum chemical calculations. Additionally, their cytotoxic and antifungal effects were initially evaluated, and a plausible biosynthetic pathway was proposed

Bioactive <i>ent</i>-Kaurane Diterpenoids from <i>Isodon rosthornii</i>

Isorosthin A (<b>1</b>), the first 20-<i>nor-</i>enmein<i>-</i>type diterpenoid, and 15 new <i>ent</i>-kauranoids, isorosthins B–P (<b>2</b>–<b>16</b>), along with 22 known analogues were isolated from the aerial parts of <i>Isodon rosthornii</i>. The structures of <b>1</b>–<b>16</b> were elucidated by means of spectroscopic analysis. The relative configuration of <b>2</b> and the absolute configuration of <b>3</b> were determined by single-crystal X-ray diffraction. Cytotoxicity evaluation against five human tumor lines showed inhibitory effects by several of the compounds tested. Furthermore, 12 of the isolates exhibited inhibitory activity against nitric oxide production in LPS-activated RAW264.7 macrophages

Laxiflorolides A and B, Epimeric Bishomoditerpene Lactones from <i>Isodon eriocalyx</i>

Laxiflorolides A (<b>1</b>) and B (<b>2</b>), two unprecedented epimeric bishomoditerpene lactones with a unique C₂₂ framework, along with laxiflorins P–R (<b>3</b>–<b>5</b>), maoecrystal P (<b>6</b>), maoecrystal C (<b>7</b>), and eriocalyxin B (<b>8</b>), were isolated from the leaves of <i>I</i>. <i>eriocalyx</i> var. <i>laxiflora.</i> The structures of <b>1</b> and <b>2</b>, including the absolute configurations, were determined by spectroscopic methods and single-crystal X-ray diffraction analysis. All of the compounds isolated were evaluated for their cytotoxicity against five tumor cell lines. Compounds <b>3</b>, <b>6</b>, and <b>8</b> showed remarkable cytotoxic activity against certain cell lines compared with the positive control

Cytotoxic <i>ent</i>-Kaurane Diterpenoids from <i>Isodon wikstroemioides</i>

Phytochemical investigation of EtOAc extracts of the aerial parts of <i>Isodon wikstroemioides</i> afforded 18 new <i>ent</i>-kaurane diterpenoids (wikstroemioidins E–V, <b>1</b>–<b>18</b>), along with 17 known analogues (<b>19</b>–<b>35</b>). The absolute configurations of <b>1</b> and <b>16</b> were confirmed by single-crystal X-ray diffraction analysis. The isolates were screened against five human tumor cell lines; compounds <b>3</b>, <b>4</b>, <b>9</b>, <b>11</b>–<b>13</b>, <b>23</b>, <b>25</b>–<b>28</b>, and <b>33</b> exhibited significant cytotoxic activity against all five, with IC₅₀ values ranging from 0.4 to 5.1 μM. In addition, 17 of the isolates strongly inhibited nitric oxide production in LPS-activated RAW264.7 macrophages