No abstract

Palaeontological data of extinct groups often sheds light on the evolutionary sequences leading to extant groups, but has failed to resolve the basal metazoan phylogeny including the origin of the Cnidaria. Here we report the occurrence of a stem-group cnidarian, Cambroctoconus orientalis gen. et sp. nov., from the mid-Cambrian of China, which is a colonial organism with calcareous octagonal conical cup-shaped skeletons. It bears cnidarian features including longitudinal septa arranged in octoradial symmetry and colonial occurrence, but lacks a jelly-like mesenchyme. Such morphological characteristics suggest that the colonial occurrence with polyps of octoradial symmetry is the plesiomorphic condition of the Cnidaria and appeared earlier than the jelly-like mesenchyme during the course of evolution.

Complex coacervates are a dense liquid phase of oppositely charged polyions formed by the associative separation of a mixture of polyions. Coacervates have been widely employed in many fields including the pharmaceutical, cosmetic, and food industries due to their intriguing interfacial and bulk material properties. More recently, attempts to develop an effective underwater adhesive have been made using complex coacervates that are based on recombinant mussel adhesive proteins (MAPs) due to the water immiscibility of complex coacervates and the adhesiveness of MAPs. MAP-based complex coacervates contribute to our understanding of the physical nature of complex coacervates and they provide a promising alternative to conventional invasive surgical repairs. Here, this review provides an overview of recombinant MAP-based complex coacervations, with an emphasis on their characterization and the uses of such materials for applications in the fields of biomedicine and tissue engineering.

No abstract

The Cambrian succession in the North China Platform comprises a mixed carbonate-siliciclastic sequence, superbly exposed in the southern part of Shandong Province, China. In order to refine the lithostratigraphy of the Cambrian succession, this paper presents detailed sedimentary logs of outcrop sections in the Jinan, Laiwu, Jining, and Linyi areas. The entire succession consists of six lithologic units: Liguan, Zhushadong, Mantou, Zhangxia, Gushan, and Chaomidian formations in ascending order. The upper boundary of the Zhushadong Formation is refined as the base of the first purple mudstone bed of the Mantou Formation. The Mantou Formation is, in turn, bounded at the top by a thick oolitic grainstone bed of the Zhangxia Formation. The upper boundary of the Gushan Formation is placed at the base of a distinct bioclastic grainstone bed of the Chaomidian Formation. The constituent members of the Zhushadong, Mantou, and Chaomidian formations are also refined. Seventeen trilobite biozones are recognized, representing the Cambrian Series 2 to the Furongian.

The current concept of the order Asaphida was proposed to accommodate some Cambrian and Ordovician trilobite clades that are characterized by the possession of a ventral median suture. The family Tsinaniidae was recently suggested to be a member of the order Asaphida on the basis of its close morphological similarity to Asaphidae. Postembryonic development of the tsinaniid trilobite, Tsinania canens, from the Furongian (late Cambrian) Hwajeol Formation of Korea, reveals that this trilobite had an adult-like protaspis. Notable morphological changes with growth comprise the effacement of dorsal furrows, sudden degeneration of pygidial spines, regression of genal spines, and loss of a triangular rostral plate to form a ventral median suture. Programmed cell death may be responsible for degenerating the pygidial and genal spines during ontogeny. Morphological changes with growth, such as the loss of pygidial spines, modification of pleural tips, and effacement of dorsal furrows, suggest that T. canens changed its life mode during ontogeny from benthic crawling to infaunal. The protaspid morphology and the immature morphology of T. canens retaining genal and pygidial spines suggest that tsinaniids bear a close affinity to leiostegioids of the order Corynexochida. Accordingly, development of a ventral median suture in T. canens demonstrates that the ventral median suture could have evolved polyphyletically, and thus the current concept of the order Asaphida needs to be revised.

Tumor invasion is an important step in the sequential process of metastasis and is subdivided into three steps, including tumor cell adhesion, migration and enzymatic degradation of the extracellular matrix and basement membrane. 1)Tumor metastasis is a major cause of death in cancer patients.2) Therefore, the discovery of agents with anti-metastatic activity, which would enable cancer patients to live longer, is a popular research objective. 3)Ginsenoside Rh1 (G-Rh1), G-Rh2, G-Rg3 and G-Rg5 are all minor saponin components with anti-tumor activity that are derived from Red ginseng. [4][5][6] Of these components, GRg5 is reported to have the most potent anti-tumor activity, but this compound is chemically unstable, which limits its potential for development into a potent anti-cancer agent. 7)Ginseng-derived saponins have no in vivo toxicity according to safety tests. Nonetheless, the development of biologicallyactive ginsenosides for food or medicinal purposes is limited and unqualified for patent status, since the components are widely known. Because of the stated limits of plant-derived ginsenosides, we aimed to synthesize novel ginsenoside-originated compounds with improved stability and anti-cancer activity without increasing toxicity. Given these goals, GRp1 was prepared on a large scale from crude ginsenosides (e.g., G-Rg5 and G-Rk1) by means of a reduction with hydrogenation. Indeed, G-Rp1 proved to be stable, had improved solubility.8,9) Furthermore, the fact that G-Rp1 displays a chemopreventive action 8) drove us to evaluate its antitumor activity in terms of anti-metastatic potential. Therefore, in this study, we examined the inhibitory activity of GRp1 on aspects of tumor metastasis using relevant in vitro and in vivo assays. MATERIALS AND METHODSMaterials G-Rp1 (Fig. 1) of 97% purity was prepared using established protocols.9) Matrigel was purchased fromMca-peptide) was purchased from Bachem (Bubendorf, Switzerland). Matrix metalloproteinase (MMP)-2 was obtained from Boehringer Mannheim (Mannheim, Germany). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole (MTT) and 4-aminophenyl-mercuric acetate (APMA) were purchased from Sigma (St. Louis, MO, U.S.A.). Antibodies to CD29 (MEM 101A, IgG1) 10) and CD43 IgG1) 11) were used in the cell-cell adhesion assays.Animals Four-week-old male C57BL/6 mice were purchased from the Korea Research Institute of Chemical Technology (Daejeon, Korea). They were maintained under conventional conditions. Laboratory pellet chow (Samyang, Inc., Daejeon, Korea) and water were administered ad libitum.Cell Line and Culture The mouse melanoma cell line (B16-F10), human umbilical vein endothelial cells (HUVECs), A549 and HCT15 cells were obtained from the American Type Culture Collection (ATCC, Manassas, VA, U.S.A.). A549, HCT15, B16-F10 and U937 cells were maintained in RPMI 1640 medium supplemented with 10% fetal bovine serum (FBS) (Gibco, Grand Island, NY, U.S.A.) and Box 115, Yusong, Daejeon 305-333, Korea. Received April 17, 2008; accepted June ...

The monophyly of the trilobite Order Asaphida has been challenged. The Superfamily Remopleuridioidea was included in the Order Asaphida, based on the ventral median suture and highly bulbous protaspis of the late Furongian–Tremadocian representatives of the group. The remopleuridioid,Haniwa quadrataKobayashi, 1933 from the Furongian (late Cambrian) Hwajeol Formation of Korea, represents a primitive morphology of the Remopleuridioidea. This trilobite does not have a typical globular morphology of asaphoid protaspis, and the free cheeks remained yoked together during the whole of the development. This supports the previous proposition that the Superfamily Remopleuridioidea should be excluded from the Order Asaphida. In addition, the evolution of a highly globular protaspis of the Ordovician remopleuridioid trilobites from the less bulbous protaspis corroborates the possibility of multiple evolutions of a highly globular protaspis. It can be argued that the possession of a highly globular protaspis does not guarantee the membership of the Order Asaphida, and thus the concept of the Order Asaphida should be emended.