ABSTRACT:The important properties of cellulosic fibers in the conditioned state are mainly influenced by fine structure. In particular, the development of new methods of spinning regenerated cellulosic fibers made from a cellulose/N-methylmorpholine-Noxide (NMMO)/H 2 O system require a better understanding of their fine structures in order to explain their special physical properties. The regenerated cellulosic films were made from cellulose/NMMO/H 2 O according to the degree of polymerization and solution concentration (wt %) of cellulose and the concentration (wt %) of NMMO in the coagulation bath. The quantification of crystal content was carried out by the resolution of the wide angle X-ray diffraction intensity distribution on the assumption that all diffracted intensities take the form of a symmetrical Gaussian distribution centering at its Bragg angle. The X-ray diffraction patterns resolved into individual integral intensities showed that the polymorphic structure mixed with part cellulose III and II was obtained for only coagulated cellulose films. The degree of crystallinity and apparent crystalline size of regenerated cellulosic films depended on the degree of polymerization, the solution concentration of cellulose, and the concentration of NMMO. The diameter of the microfibril decreased with an increase in the concentration of NMMO.

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It has been shown that green tea catechins (GTC) suppress proliferation of vascular smooth muscle cells (VSMCs) and that epigallocatechin-3-gallate (EGCG), which is a major constituent of GTC, selectively inhibits the platelet-derived growth factor-BB (PDGF-BB)-induced intracellular signaling transduction pathway. Vascular smooth muscle cell proliferation is one of major mechanisms of restenosis following percutaneous coronary intervention. This study tested whether GTC can inhibit VSMC proliferation and prevent neointimal formation in a rat carotid artery injury model. Vascular smooth muscle cell proliferation inhibition was analyzed with [3H]thymidine incorporation. Green tea catechins were applied to the endothelium-denuded carotid arteries of rats for 20 min. Angiography and morphometric analysis was performed after 2 weeks. Green tea catechins decreased [3H]thymidine incorporation stimulated with PDGF-BB dose dependently. In the absence of PDGF-BB, the decrement of [3H]thymidine incorporation was evident above a concentration of 10 micro g/ml of GTC. Carotid arteriographic evaluation showed that the minimum luminal diameter in the GTC-treated group (n=12) was 5.9 +/- 1.6 arbitrary units (a.u.) and was significantly larger than in the control group (4.3 +/- 1.4 a.u., n=10) ( P <0.05). The GTC-treated group also showed a significant reduction in neointimal formation compared with the control group (0.29 +/- 0.11 vs 0.42 +/- 0.10 mm2, P < 0.05). To identify the active ingredients, we performed a similar experiment using EGCG. The effects of EGCG were similar to those of GTC. Green tea catechins effectively inhibited VSMC proliferation. Neointimal formation was prevented in the rat carotid artery injury model by local delivery of GTC. As EGCG showed similar effects, it may be one of the major constituents of GTC having these effects.

ObjectiveTo determine the possibility of a new measurement tool using electromyography and ultrasonography for quantitative spasticity assessment in post-stroke patients.MethodsEight hemiplegic stroke patients with ankle plantarflexor spasticity confirmed by a Modified Ashworth Scale (MAS) were enrolled. Spasticity was evaluated using the MAS and Modified Tardieu Scale (MTS). Each subject underwent surface electromyography (sEMG) using the Brain Motor Control Assessment (BMCA) protocol and was compared with a healthy control group. Using ultrasonography, muscle architecture and elasticity index were measured from the medial gastrocnemius muscle (GCM) on the affected and unaffected sides. ResultsMAS and MTS revealed significant correlation with sEMG activity. The fascicle length and pennation angle were significantly decreased in the medial GCM on the hemiplegic side compared with the unaffected side. The elasticity index of the spastic medial GCM was significantly increased compared with the unaffected side. The MTS X and R2–R1 values were significantly correlated with the elasticity index in the hemiplegic GCM. The relationship between clinical evaluation tools and both BMCA and sonoelastography was linear, but not statistically significant in the multiple regression analysis.ConclusionThe BMCA protocol and ultrasonographic evaluation provide objective assessment of post-stroke spasticity. Further studies are necessary to conduct accurate assessment and treatment of spasticity.

Morphological and anatomical features of mature embryos and seedlings were observed at different growth stages in the parasitic angiosperm Cuscutajaponica Choisy. The spirally coiled embryos from scarified seeds had no cotyledons but possessed blunt radicles. Seeds germinated at 30~ in the dark. Although most embryo cells incubated for 16 h did not have starch grains, the shoot cells of three-day-old seedlings possessed numerous starch grains. After these seedlings were transferred to a lightened growth chamber, all the shoot apical regions of seedlings grown for 6, 8, and 10 days became greenish and hooked. Most of the shoot cells, including the green apical parts, contained abundant starch grains. The hooks opened only when one seedling made contact with another seedling, This suggested that the green and hooked shoot apical regions played an important role in searching for and twining about their host plants. In some two-day-old seedlings, the massive roots were circular or semi-circular. This enabled the shoot axes to stand erect on some substratum. It would assist the shoots in making contact with the host plant. In eight-day-old seedlings, the green apical regions also were hooked and the roots were considerably degraded.Keywords: Anatomy, Cuscuta japonica, Embryo, Morphology, Parasitic angiosperm, SeedlingThe seedlings of Cuscuta have chlorophyll that enables photosynthesize (Zimmermann, 1962;Pattee et al., 1965). Although all the Cuscuta species still contain chlorophyll a and b while exploiting their host plants (Macleod, 1963;Ismail and Obeid, 1976), the rate of photosynthesis is decreased (Pattee et al., 1965). The excised stem tips of C. campestris, grown in vitro, produce a considerable amount of chlorophyll. This probably plays an important role in maintaining the growth of the culture (Loo, 1946). Fujita (1964) has characterized the mature embryo of C. japonica as a spirally coiled, yellow cylindrical structure, with a tapering apex, no cotyledon, and having a blunt radicle without a root cap. Truscott (1966) has suggested that in embryo culture of C.gronovii, the loss of both cotyledons and roots was a single embryonic event in the evolution of Cuscuta from its autotrophic ancestors. The morphology and anatomy of early seedlings in C. pedicellata has been studied by Lyshede (1985), who has also observed the fine structures of the tuberous radicular end (Lyshede, 1986) and the one-week-old seedlings in the same species (Lyshede, 1989). However, the function of organs during their autotrophic growth *Corresponding author; fax +82-62-230-7363 e-mail leekb@mail.chosun.ac.kr period is not yet clearly understood. The present study attempts to describe some morphological and anatomical features of C. japonica embryos and seedlings at various developmental stages, and to evaluate these features in view of their parasitic roles. MATERIALS AND METHODS Seed GerminationWe scarified mature, dormant seeds of C. japonicaChoisy with concentrated sulfuric acid for 25, 35, or 45 min, then rinsed them in tap water a...