• Nutritional Sciences
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• v.7 no.3
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• pp.144-150
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• 2004

We have investigated the effect of calcium spirulan(Ca-SP) isolated from a blue-green alga Spirulina platensis, which is a sulfated polysaccharide chelating calcium and mainly composed of rhamnose and fructose, on invasion of both B16- BL6 melanoma cells, Colon 26 carcinoma and HT-1080 fibrosarcoma cells through reconstituted basement membrane (Matrigel). Ca-SP significantly inhibited the invasion of these tumor cells through Matrigel/fibronectin-coated filters in a concentration-dependent manner. Ca-SP also inhibited the haptotactic migration of tumor cells to laminin, but it had no inhibitory effect on tumor cell migration to fibronectin-coated filters. Ca-SP prevented the adhesion of B16-BL6 cells to Matrigel- and laminin-substrates but did not affect the adhesion to fibronectin. The pretreatment of tumor cells with Ca-SP inhibited the adhesion to laminin in a concentration-dependent fashion, while the pretreatment of laminin-substrates did not. Ca-SP had no effect on the production and activation of type IV collagenase in gelatin zymography. In contraset, Ca-SP significantly inhibited degradation of heparan sulfate by purified heparanase. The experimental lung metastasis was significantly reduced by co-injection of B16-BL6 cells with Ca-SP in a dose-dependent manner. Seven intermittent ⅰ.ⅴ. injection of 100$\mu\textrm{g}$ of Ca-SP caused a marked decrease of lung tumor colonization of B16-BL6 cells in a spontaneous lung metastasis model. These results suggest that Ca-SP, a novel sulfated polysaccharide, could reduce the lung colonization of B16-BL6 melanoma cells in experimental metastasis model, by inhibiting the tumor invasion of basement membrane Matrigel, probably through the prevention of the adhesion and migration of tumor cells to laminin-substrate and of the heparanase activity.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.297-300
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• 1996

LBD-001, a recombinant human interferon $\gamma$ produced by genetically engineered yeast as a host system, was administered intraperitoneally to Sprague-Dawley male rats from premating to mating period at least for 60 days and to female rats from at least for 2 weeks before mating to early gestation period (from day 0 to 7 of gestation) at dose levels of $0.35\times10^6, 0.39\times10^6, and 1.38\times10^6$ I.U./kg/day. In the positive control group, ethynylestradiol ($EE_2$; 40 $\mu\textrm{g}$/kg/day) was subcutaneously administered only to female rats during the early gestation period. Effects of the test agents on reproductive performances of the male or female rats and embryonic development were as followings; (1) No significant changes by the treatment of LBD-001 were observed in general behaviors, body weight, food and water consumption, and necropsy of parent animals. However, significant decreases of body weight, food consumption, and water consumption were observed in ($EE_2$ -treated female rats. (2) Mating performances and fertility of parent animals were not significantly affected by the treatment of LBD-001. In ($EE_2$ -treated females, however, the fertility was completely inhibited. (3) No changes in resorption rate and external abnormality of F1 fetuses were observed by the treatment of LBD-001. The results show that LBD-001 at the dose of $1.38\times10^6$ I.U./kg/day or less does not affect general toxicity and reproductive function of parent animals and embryonic development of F1 fetuses.

• Restorative Dentistry and Endodontics
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• v.28 no.6
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• pp.491-497
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• 2003

The purpose of this study was to evaluate the correlation between hybrid layer thickness and bond strength using confocal laser scanning microscope and microtensile bond strength test of two adhesive systems. The dentin surface of human molars. sectioned to remove the enamel from the occlusal surface. Either Scotchbond Multi-Purpose(3M Dental Product, St. Paul, MN, U.S.A) or Clearfil SE Bond (Kuraray, Osaka, Japan) was bonded to the surface. and covered with resin-composite. The resin-bonded teeth were serially sliced perpendicular to the adhesive interface to measure the hybrid layer thickness by confocal laser scanning microscope. The specimen were trimmed to give a bonded cross-sectional surface area of $1\textrm{mm}^2$, then the micro-tensile bone test was performed at a cross head speed of 1.0 mm/min. All fractured surfaces were also observed by stereomicroscope. There was no significant differences in bond strengths the materials(p>0.05). However. the hybrid layers of three-step dentin adhesive system, SM, had significantly thicker than self-etching adhesive system. CS(p<0.05). Pearson's correlation coefficient showed no correlation between hybrid layer thickness and bond strengths(p>0.05). Bond strengths of dentin adhesive systems were not dependent on the thickness of hybrid layer.

• Journal of the Korean Magnetics Society
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• v.7 no.6
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• pp.299-307
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• 1997

NdFeB films have been grown onto Si(100) substrate by a KrF pulsed laser ablation of the targets of $Nd_xFe_{90.98-x}B_{9.02}$ (x=17.51~27.51) at the substrate temperature of 620~700 $^{\circ}C$ and the laser beam energy density of 2.75~5.99 J/$\textrm{cm}^2$. The films exhibit no preferred orientation, however, good hard magnetic properties were produced from as-deposited condition : $4{\pi}M_s$=7 kG, $4{\pi}M_r$=4 kG, and $H_c$=300~1000 Oe. The depositon rate was not greatly influenced by changing the substrate temperature, but it increases linearly by increasing the beam energy density. The beam energy density of 3 J/$\textrm{cm}^2$ gave the optimal condition to have the highest $4{\pi}M_r$ and $H_c$ as well. The higher content of Nd induces a higher coercivity and $4{\pi}M_r$ at the same time without prominent change in $4{\pi}M_s$.

• Investigative Magnetic Resonance Imaging
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• v.4 no.2
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• pp.94-99
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• 2000

Purpose : With the use of localized, water-suppressed in vivo $^1H$ magnetic resonance spectroscopy (MRS), we evaluated the proton metabolic alterations in patients with chronic alcoholism and healthy normal controls. Material and Methods : Patients with chronic alcoholism (N = 10) and normal control subjects (N = 10) underwent MRS examinations using a stimulated echo acquisition mode (STEAM) pulse sequence with $2{\times}2{\times}2{\;}\textrm{cm}^3$ volume of interest (VOI) in the left cerebellum and basal ganglia. Proton metabolite ratios relative to creative (Cr) were obtained using a Marquart algorithm. Results : The specific feature in patients with chronic alcoholism was a significant decrease of N-acetylaspartate (NAA)/Cr ratio in the left cerebellum, compared with normal controls. No clear correlation of other metabolite ratios such as choline (Cho)/Cr and inositols (Ins)/Cr was established. Conclusion : Our preliminary study suggests that the reduction of NAA/Cr ratio may indicate neuronal loss in patients with chronic alcoholism. Thus, in vivo 1H MRS may be a useful modality in the clinical evaluation of patients with chronic alcoholism based on the proton metabolite ratios.

• Restorative Dentistry and Endodontics
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• v.28 no.1
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• pp.11-22
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• 2003

This study compared the dentin adhesion to composite resin according to air-dry, blot dry, application of rewetting agent on air-dry or blot dry dentin surface by microleakag test and SEM observation. For microleakage test, class V cavity preparations with dentinal margins were prepared on both buccal and lingual surfaces of 40 extracted human molars. For SEM observation, occlusal dentin of 20 extracted human molars were exposed. After etched the dentin, prepared teeth were randomly divided into four groups; D group: air dry for 10-15 sec., B group: blot dry with moist cotton pellet, D-R group: air dry and rewet with Aqua-Prep F for 20 sec., B-R group: blot dry and rewet with Aqua-Prep F for 20 sec. Treated cavities and surfaces were filled or constructed using One-Step adhesives and Aelitefil composite resins. Specimens were stored in distilled water for 24 hours. For microleakage test, the specimens were thermocycled and soaked into 2% methylene blue. The specimens were sectioned longitudinally and evaluated for microleakage under steromicroscope. The data were statistically analysed by Kuskal-Wallis Test, Mann-Whitney and Wilcoxon signed ranked tests. For SEM observation, the specimens were bisectioned mesiodiatally. After decalcified and deproteinized, specimens were observed under SEM. The results of this study were as follows; 1. The microleakges on dentinal margin were the highest in D group compared with B group, D-R group, and B-R group(p<0.05). But there was no significant difference between B group, D-R group and B-R group. 2. D group showed gap and a few resin tags between dentin and composite resin. 3 B group, D-R group, and B-R groups showed close adaptation between dentin and composite resin. It showed that resin rags in B group were numerous and long, in D-R group were few and short, in B-R group were numerous and short or long. 4. Adhesive layer showed in D-R group ($10{\;}\mu\textrm{m}$) and B-R group ($3{\;}\mu\textrm{m}$) In conclusion, use of rewetting agent to dry dentin was efficient to dentin adhesion, also it did not provide reverse effect on blot dry dentin.

• Microbiology and Biotechnology Letters
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• v.7 no.1
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• pp.23-30
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• 1979

Fungi which produce red pigment were isolated from tapioca chips, Korean Koji, air, and plant leaves. Among the Fungi, T-1 strain was selected as test strain. This strain was identified as a Monatcus sp. by the morphological propeties. Various culture conditions, and physical and physiological characteristics of red pigment were studied. According to the studies of culture conditions, optimum condition was found to be pH 6.5; 4 days of incubation; temperature, 32~33 c: 3.5％ of Tapioca chips powder as carbon source, 0.2％ of sodium nitrate as nitrogen source and 100 ml of medium in the 500 ml Erlenmyer flask at a rotary shaker (rpm180) as aeration condition. Also effective levels of vitamins, amino acids and inorganic compounds was found to be l$\mu\textrm{g}$/ml of folic acid and niacin; 0.3％ of L-arginine, L-glutamic acid and L-proline; and 0.001％ of manganese dioxide giving good results.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.33-41
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• 1999

Whereas as selective inhibitor of monoamine oxidase type B, ${\ell}-deprenyl$ (selegiline), is now widely used in the treatment of Parkinson's disease, the precise action mechanism of the drug remains elusive. In this study, to investigate protective effect of ${\ell}-deprenyl$ against the dopamine depletion induced by 6-hydroxydopamine (6-OHDA), the changes in tissue contents of dopamine, serotonine (5-HT) and their metabolites by ${\ell}-deprenyl$ were examined in intact and 6-OHDA-lesioned rat brain. In intact rats, a single intraperitoneal (i.p.) administration of ${\ell}-deprenyl$ showed a no change in striatal dopamine and its metabolites at low concentrations (0.25 and 1 mg/kg), but significantly inhibited dopamine metabolism at a higher concentration (10 mg/kg). The repeated administration of ${\ell}-deprenyl$ (0.25 and 1 mg/kg, i.p., for 21 consecutive days) reduced the contents of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA) in dose-dependent manners without changes in dopamine content. Bilateral intracerebroventricular (i.c.v) infusion of 6-OHDA ($100{\;}\mu\textrm{g}/10{\;}{\mu}{\ell}/hemisphere$) depleted dopamine in striatum and septum by 81% and 90% respectively. When rats were pretreated with ${\ell}-deprenyl$ before 6-OHDA administration, the striatal and septal dopamine levels were significantly increased by about 3.0-fold and 3.4-fold, respectively, compared to the untreated 6-OHDA-lesioned rat. Pretreatment of ${\ell}-deprenyl$ also significantly enhanced the dopmaine metabolites, DOPAC, HVA and 3-methoxytyramine, in the striatum, and DOPAC in the septum. These results indicate that a ${\ell}-deprenyl$ pretreatment prevents 6-OHDA-induced depletion of striatal dopamine and its metabolites.

• Restorative Dentistry and Endodontics
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• v.29 no.3
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• pp.281-287
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• 2004

The purposes of this study were to evaluate the effect of adhesive property on microtensile bond strength and to determine the failure mode. Flat occlusal dentin surfaces were prepared using low-speed diamond saw. The dentin was etched with 37％ phosphoric acid. The following adhesives were applied to the etched dentin to manufacturer's directions： Scotchbond Multi-Purpose in group SM, Prime＆Bond NT in group NT, Scotchbond Multi-Purpose followed by Tetric-flow in group TR. After adhesive application, a cylinder of resin-based composite was built up on the occlusal surface. Each tooth was sectioned vertically to obtain the $1{\;}{\times}{\;}1\textrm{mm}^2$ "sticks". Microtensile bond strength were determined. Each specimen was observed under stereomicroscope and scanning electron microscope (SEM) to examine the failure mode. Data were analyzed using one way ANOVA. The results of this study were as follows：1. The microtensile bond strength value were：group SM ($18.98{\pm}3.01MPa$). group NT ($16.01{\pm}4.82MPa$) and group TR ($17.56{\pm}3.22MPa$). No significant statistical differences were observed among the groups (P>0.05). 2. Most of specimens showed mixed failure. In group TR, there was a higher number of specimens showing areas of cohesive failure in resin.

• Reproductive and Developmental Biology
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• v.28 no.2
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• pp.113-117
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• 2004

The present study was carried out to examine the effects of $O_2$ concentrations and culture media (North Carolina State University (NCSU)-23, porcine zygote medium(PZM)-3 or PZM-4) on in vitro development of porcine IVM/IVF embryos. Porcine oocyte-cumulus complexes were cultured in BSA-free NCSU-23 medium containing porcine follicular fluid (10%), cysteine (0.9 mM), $\beta$-mercaptoethanol (25 $\mu\textrm{g}$/$m\ell$), epidermal growth factor (10 ng/$m\ell$) and hormonal supplements (PMSG and hCG: 10 IU/$m\ell$) for 20∼22 h. They were then cultured in the same medium but without hormonal supplements for an additional 20∼22 h. After culture, cumulus-free oocyte were coincubated with liquid boar spermatozoa for 5∼6h. Putative zygotes were transferred to NCSU-23, PZM-3 and PZM-4 medium under the condition of 5% $O_2$ or 20% $O_2$ concentrations. At 48 h, no mean differences were found in cleavage rates. However, the rates of blastocyst formation at day 7 after in vitro fertilization were significantly higher in PZM-3 medium under the condition of 5% $O_2$ concentration than other treatments (19.9$\pm$2.4 vs. 11.1$\pm$2.0 to 16.0$\pm$2.5%, P<0.05). The total cell numbers of blastocysts were significantly higher in 5% $O_2$ than in 20% O2 (P<0.05). However, no differences was found among the culture media within each $O_2$ concentrations. In conclusion, the use of PZM-3 medium in 5% $O_2$ concentration was effective on in vitro development of porcine IVM/IVF embryos.