• Microbiology and Biotechnology Letters
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• v.22 no.4
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• pp.360-367
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• 1994

The effect of various nutrients for the production of the anti-complementary polysaccha- ride by Flammulina velutipes, was examined and the partial purification of the polysaccharide was carried out. The culture conditions and medium compositions considerably influenced the anti-complementary activity of the polysaccharides. When a culture was carried out at 23$\circ$C and pH 5.5 for 6 days in the synthetic medium supplemented with galactose and NaNO$_{3}$, the production of the anti-complementary polysaccharide was maximized. The crude polysaccharide, FV-1 was isolated from the culture broth and partially purified into two fractions, FV-1-II and FV-1-III by gel filtration using Sephadex G-100. FV-1-II was mainly consisted of xylose, mannose, galactose and glucose, and rhamnose, mannose and galactose, for FV-1-III. Also, the anti-complementary activity of FV-1-III was reduced partially in the absence of the Ca ion. When crossed immunoelect- rophoresis using anti-human C3 serum was carried out after incubation of normal human serum with the FV-1-III in the Ca ion free condition, a cleavage of C3 precipitin line was observed. These results indicate that the mode of complement activation by polysaccharide from Flammulina velutipes is via not only the classical pathway but also the alternative pathway.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.19-23
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• 2010

Recently, marine organisms are emerging as a leading group for identifying and extracting novel bioactive substances. These substances are known to possess a potential regarding not only as a source of pharmaceutical products but also their beneficial effects on humans. Among the substances, antimicrobial peptides (AMPs) specifically have attracted considerable interest for possible use in the development of new antibiotics. AMPs are characterized by relatively short cationic peptides containing the ability to adopt a structure in which cationic or hydrophobic amino acids are spatially scattered. Although a few reports address novel marine organisms-derived AMPs, their antimicrobial mechanism(s) are still remain unknown. In this review, we summarized the peptides previously investigated, such as Pleurocidin, Urechistachykinins, Piscidins and Arenicin-1. These peptides exhibited significant antimicrobial activities against human microbial pathogens without remarkable hemolytic effects against human erythrocytes, and their mode of actions are based on permeabilization of the plasma membrane of the pathogen. Therefore, the study of antimicrobial peptides derived from marine organisms may prove to be useful in the design of future therapeutic antimicrobial drugs.

• Proceedings of the Plant Resources Society of Korea Conference
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• 1999.10a
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• pp.58-64
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• 1999

As indicated by Chinese letters "사혁" (sha-ji) is the ripe fruit of Seabuckthron (Hippophae rhamnoides Linneus) Family Flaeagnaceae is one of ancient natural medicine used by the Tibetan and Mongolian nationallites with ancient methods to treat desease, It is an effectiv Traditional Tibetan medicine. Bud only now are they beginning to be understood in the world of modern medicine. Hippophae was written in the book of Traditional Tibetan Medicine - "Somalaza" (8th century), "Sibuyidian" (1840) and "Jingzhubencao" (Qing Dynasty). The "Sibuyidien" was trnslated in to the Russian and published at 1903 in the Russian. Then the Russian bigan to study on Hippophae and they have achieved great successes. The Chinese scientists began to study on the chemical constituent and medical action with modern technique at 1952. With more than 40 years painstaking eport they have conceived and used a wide variety of experimental screening systems, achieved successes. Finally the)1 with one's own tests has keen verified that the crude drug being various kind of bioactive substance could Inhibits tumor, increase immunity, wipe out free radical, prevent disease of cardiovascular system, have anti-radiation, anti-inflammeutory effects. At 1977 the Hippophae rhamnoides was written in Chinase Pharmacopoeia.e rhamnoides was written in Chinase Pharmacopoeia.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.312-315
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• 2014

So as to evaluate its use an immune stimulator in humans, the toxicity and action against immune cells by an anti-yeast substance (AYS), a bacterial proteoglycan, were investigated. The AYS did not possess hemolytic activity with human red blood cells (hRBC). Nor did it exhibit cytotoxicity against human peripheral blood mononuclear cells (hPBMC). In addition, the AYS did not induce hPBMC proliferation, but it did agglutinate hPBMCs in vitro. Moreover, hPBMC induced inflammatory cytokines such as IL-6, IL-5, IFN-${\gamma}$ and TNF-${\alpha}$ with the AYS during culture. Compared with alum, the AYS as an adjuvant has an increased antibody production rate against bovine serum albumin (BSA) in mice.

• Carbon letters
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• v.8 no.2
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• pp.115-119
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• 2007

Properties of carbon blacks and carbon black/SBR rubber composites filled by surface modified carbon blacks were examined. Although the specific surface area of carbon blacks increased after the surface modifications with heat, acid, and base, there were no obvious changes in resistivity. The composites filled by heat treated carbon blacks showed a higher tensile strength and elongation than those filled by raw blacks. The acid and base treated carbon blacks filled composites also showed higher tensile strength but similar elongation values with those filled by raw blacks. With increasing loading ratio, both tensile strength and elongation increased, and appeared a maximum value at 30-40 phr. Modulus at 300% strain remained increasing with further loading of carbon blacks. At the same loading, the heat treated black filled composites showed similar modulus values with composites filled by raw blacks but for base and acid treated black filled composites much higher values were obtained. After the surface modification, the functional groups which played an important role in reinforcement action were changed.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.207-210
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• 2014

Viral infections are capable of inducing reactive oxygen species (ROS) production in the infected cells and antioxidants have been reported to have antiviral activities against many viruses. In this study, an antiviral assay using the cytopathic effect (CPE) reduction method revealed that gallic acid possesses good anti-coxsackievirus B3 (CB3) and coxsackievirus B4 (CB4) activities, reducing the formation of visible CPE. However, ribavirin did exhibit weak anti-CB3 and CB4 activities and was unable to prevent CPE. Therefore, we conclude that the inhibition of CB3 or CB4 production by gallic acid may be due to its general action as an antioxidant.

• Plant Resources
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• v.3 no.1
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• pp.93-97
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• 2000

As indicated by Chinese letters “沙赫” (sha-ji) is the ripe fruit of Seabuckthron(Hippophae rhamnoides Linneus) family Flaeagnaceae is one of ancient natural medicine used by the Tibetan and Mongolian nationallites with ancient methods to treat desease. It is an effectiv Traditional Tibetan medicine. Bud only now are they beginning to be understood in the world of modern medicine. Hippophae was written in the book of Traditional Tibetan Medicine - “Somalaza” (8th century), “Sibuyidian” (1840) and “Jingzhubencao” (Qing Dynasty). The “Sibuyidien” was trnslated in to the Russian and published at 1903 in the Russian. Then the Russian bigan to study on Hippophae and they have achieved great successes. The Chinese scientists began to study on the chemical constituent and medical action with modern technique at 1952. With more than 40 years painstaking eport they have conceived and used a wide variety of experimental screening systems, achieved successes. Finally they with one's own tests has keen verified that the crude drug being various kind of bioactive substance could inhibits tumor, increase immunity, wipe out free radical, prevent disease of cardiovascular system, have anti-radiation, anti-inflammeutory effects. At 1977 the Hippophae rhamnoides was written in Chinase Pharmacopoeia.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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• pp.43-53
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• 2019

The anticancer activity of guava (Psidium guajava L.) leaf extract (GLE) occurs via the induction of apoptosis in cancer cells. However, the mechanism behind GLE-induced apoptosis in the human hepatocellular carcinoma cell line HepG2 remains unclear. In the present study, we investigated the apoptotic effects and mechanism of action of GLE in cultured HepG2 cells. The results showed that GLE induced reactive oxygen species (ROS) synthesis and disrupted the mitochondrial membrane potential (${\Delta}{\Psi}m$). Moreover, GLE increased the expression of apoptotic pathway proteins, such as the cleaved forms of caspase-3, -8, and -9; the translocation of Bax and cytochrome c (cyt-c) from the mitochondria to the cytosol; and the downregulation of Bcl-2. In addition, p53 protein expression was increased upon GLE treatment. These observations indicate that the GLE-induced apoptosis in HepG2 cells is mediated by mitochondrial ROS generation, followed by caspase activation and cyt-c release, suggesting that GLE may be a promising candidate for the development of novel drugs for the treatment of liver cancers.

• Biomedical Science Letters
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• v.27 no.4
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• pp.270-276
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• 2021

Physiological agents trigger a signaling process called "inside-out signaling" and activated platelets promote adhesion, granule release, and conformational changes of glycoprotein IIb/IIIa (αIIb/β₃). Activated αIIb/β₃ interacts with fibrinogen and initiates a second signaling step called "external signaling". These two signaling pathways can cause hemostasis or thrombosis, and thrombosis is a possible medical problem in arterial and venous vessels, and platelet-mediated thrombosis is a major cause of cardiovascular disease (CVD). Therefore, modulating platelet activity is important for platelet-mediated thrombosis and cardiovascular disease. Esculetin is a coumarin-based physiologically active 6,7-dihydroxy derivative known to have pharmacological activity against obesity, diabetes, renal failure and CVD. Although some studies have confirmed the effects of esculetin in human platelet activation and experimental mouse models, it is not clear how esculetin has antiplatelet and antithrombotic effects. We confirmed the effect and mechanism of action of escultein on human platelets induced by collagen. As a result, esculetin decreased Ca²⁺ recruitment through upregulation of inositol 1, 4, 5-triphosphate receptor. In addition, esculetin upregulates cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP)-dependent pathways and inhibits fibrinogen binding and thrombus contraction. Our results demonstrate the antiplatelet effect and antithrombotic effect of esculetin in human platelets. Therefore, we suggest that esculetin could be a potential phytochemical for the prevention of thrombus-mediated CVD.

• Restorative Dentistry and Endodontics
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• v.47 no.2
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• pp.18.1-18.9
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• 2022

Objectives: This study evaluated alterations in neuronal conductivity related to calcium silicate cements (CSCs) by investigating compound action potentials (cAPs) in rat sciatic nerves. Materials and Methods: Sciatic nerves were placed in a Tyrode bath and cAPs were recorded before, during, and after the application of test materials for 60-minute control, application, and recovery measurements, respectively. Freshly prepared ProRoot MTA, MTA Angelus, Biodentine, Endosequence RRM-Putty, BioAggregate, and RetroMTA were directly applied onto the nerves. Biopac LabPro version 3.7 was used to record and analyze cAPs. The data were statistically analyzed. Results: None of the CSCs totally blocked cAPs. RetroMTA, Biodentine, and MTA Angelus caused no significant alteration in cAPs (p > 0.05). Significantly lower cAPs were observed in recovery measurements for BioAggregate than in the control condition (p < 0.05). ProRoot MTA significantly but transiently reduced cAPs in the application period compared to the control period (p < 0.05). Endosequence RRM-Putty significantly reduced cAPs. Conclusions: Various CSCs may alter cAPs to some extent, but none of the CSCs irreversibly blocked them. The usage of fast-setting CSCs during apexification or regeneration of immature teeth seems safer than slow-setting CSCs due to their more favorable neuronal effects.