• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.268-268
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• 2006

Due to their multipotency, stem cells can differentiate into a variety of specialized cell types, such as chondrocytes, osteoblasts, myoblasts, and nerve cells. As an alternative to mature tissue cells, stem cells are of importance in tissue engineering and regenerative medicine. Since interactions between scaffold and cells play an important role in the tissue development in vitro, synthetic oligopeptides have been immobilized onto polymeric scaffolds to improve specific cell attachment and even to stimulate cell differentiation. In this study, chondrogenic differentiation of stem cells was evaluated using surface-modified PLLA scaffolds, i.e., either hydrophilic acrylic acid (AA)-grafted PLLA or RGD-immobilized one. Porous PLLA scaffolds were prepared using a gas foaming method, followed by plasma treatment and subsequent grafting of AA to introduce a hydrophilicity (PLLA-PAA). This was further processed to fix RGD peptide to make an RGD-immobilized scaffold (PLLA-PAA-RGD). Stem cells were seeded at $1{\times}10^{6}$ cells per scaffold and the cell-PLLA constructs were cultured for up to 4 weeks in the chondrogenic medium. Using these surface-modified scaffolds, adhesion, proliferation, and chondrogenic differentiation of stem cells were evaluated. The surface of PLLA scaffolds turned hydrophilic (water contact angle, 45 degrees) with both plasma treatment and AA grafting. The hydrophilicity of RGD-immobilized surface was not significantly altered. Cell proliferation rate on the either PLLA-PAA or PLLA-PAA-RGD surface was obviously improved, especially with the RGD-immobilized one as compared to the control PLLA one. Chondrogenic differentiation was clearly identified with Safranin O staining of GAG in the AA- or RGD-grafted PLLA substrates. This study demonstrated that modified polymer surfaces may provide better environment for chondrogenesis of stem cells.

• The Journal of Korean Medicine
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• v.26 no.3 s.63
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• pp.239-248
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• 2005

Objectives : Electroacupuncture (EA)-induced analgesia has been known to be mediated through the activation of opioid, noradrenergic and serotonergic receptors. However, little study on serotonergic mechanism has been performed in an animal model of chronic pain. The present study was designed to elucidate the type of serotonergic receptors responsible for EA analgesia in the chronic pain model. Methods : In rats with complete Freund's: adjuvant-induced inflammation and spinal nerve injury, spinal wide dynamic range (WDR) cell responses to graded electrical stimulation of afferent C fiber were recorded before and after spinal application of selective 5-hydroxytryptamine (5-HT) receptor antagonists. EA stimulation (2Hz, 0.5msec, 3mA) was applied to the contralateral Zusanli point for 30 min. Results : In both models of chronic pain, WDR cell responses were greatly inhibited after EA stimulation. EA-induced inhibition of WDR celt responses was significantly attenuated by spinal application of non-selective 5-HT receptor antagonist, dihydroergocristine Of 5-HT receptor antagonists tested, 5-HT1A (WAY 100635) and 5-HT2 (LY53857) receptor antagonists strongly reduced an ability of EA stimulation to inhibit WDR cell responses. However, 5-HT1B (GR55562) and 5-HT3 (LY278584) receptor antagonists also had weak but significant blocking action on EA-induced inhibitory effect on chronic pain. Conclusions : Dorsal hem cell responses, afferent C fiber stimulation, chronic pain, electroacupuncture, serotonergic receptors.

• YAKHAK HOEJI
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• v.39 no.2
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• pp.161-168
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• 1995

Brain dopamine systems play a central role in the control of movement, hormone release, and many complex behavior. The action of dopamine at its synapse is terminated predominately by high affinity reuptake into presynaptic terminals by dopamine transporter (DAT). The dopamine transporter(DAT) is membrane protein localized to dopamine-containing nerve terminals and closely related with cocaine abuse, Parkinsonism, and schizophrenia. In present study, the recombinant plasmid pRc/CMV-DAT, constructed by subcloning of a cDNA encoding a bovine DAT into eukaryotic expression vector pRc/CMV, was stably transfected into CV-1 cells(monkey kidney cell line). The DAT activities in the cell lines selected by Geneticin$^{R}$ were determined by measuring the uptake of $[^3H]$-dopamine. The transfected cell lines showed 30-50 fold higher activities than untransfected CV-1 cell line, and this result implies that DAT is well expressed and localized in transfected cells. The transfected cells accumulated $[^3H]$-dopamine in a dose-dependent manner with a $K_{m}$ of 991.6nM. Even though high doses of norepinephrine, epinephrine, serotonin, and choline neurotransmitters inhibited the uptake of $[^3H]$-dopamine, DAT in transfected cell line was proven to be much more specific to dopamine. The psychotropic drugs such as GBR12909, CFT, normifensine, clomipramine, desipramine, and imipramine inhibited significantly the dopamine uptake in tissue culture cells stably transfected with DAT cDNA. Radioactive in situ hybridization was done to map the cellular localization of DAT mRNA-containing cells in the adult rat central nervous system. The strong hybridization signals were detected only in the substantia nigra pars compacta and ventral tegmental area. The restricted anatomical localization of DAT mRNA-containing cells confirms the DAT as a presynaptic marker of dopamine-containing cells in the rat brain.

• Korean Journal of Head & Neck Oncology
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• v.19 no.1
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• pp.67-70
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• 2003

Out of entire salivary tumor, 1.7% are malignant lymphoma developed in salivary gland and it is usually mucosa associated lymphoid tissue (MALT) lymphoma developed in salivary gland. In the case of Non-Hodgkin lymphoma, the most frequently involved extanodal sites of diffuse large B cell lymphoma are bone, skin, thyroid, gastrointestinal tract, and lung. Development in salivary gland is very rare. A 69 years old male patient who have found Lt. submandibular gland (SMG) mass a month ago is suspected of malignancy from his FNA result, so histologic exam by SMG resection was operated. According to histopathologic exam, large B cell lymphocyte infiltratration were generally shown as diffuse and lymphoepitheliallesion were not found. In immunostaining, CD79a showed positive and CD3, CAM5.2 showed negative which diagnosed as diffuse large B cell lymphoma. As Ann Arbor stage I, CEOP-B chemotherapy was used 3 times as treatment without any recurrence. In the case of malignant lymphoma in salivary gland, it develops as painless mass in ipsilateral side. If found in parotid gland, it is rare to have facial nerve falsy and pathologically diagnosed as lymphocytes of abnormal type of monoclonal immunostaining must be provided as evidence. Combined therapy is known as most effective treatment for intermediate grade.

• Herbal Formula Science
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• v.7 no.1
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• pp.131-141
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• 1999

In order to eludidate the mechanism of oxidative stress in cultured spinal motor neurons damaged by oxygen free radicals, cytoxicity was assesed by MTT assay and NR assay after spinal motor neurons from mouse were cultured in media containing various concentrations of xanthine oxidase(XO) and hypoxanthine(HX) for 3 hours. In addition, neuroprotective effects of several herb extracts on oxidant-induced neurotoxicity were examined in these cultures, compared with nerve growth factors such as basic fibroblast growth factor(bFGF). XO/HX decreased cell viability in dose- and time dependent manners on cultured mouse spinal motor neurons, and MTT50 and NR50 values were measured at 20mU/ml XO and 0.1mM HX for 3 hours in these cultures. bFGF significantlt increased cell viability. In neuroprotective of herb extracts, Epimedium Koreanum Nakai(EK) and Alpinia oxphylla Mig(IJI) was very effective in the prevention of the neurotoxicity induced by XO/HX in cultured mouse spinal motor neurons. From the above results, it is suggested that XO/HX shows toxic effect in cultured mouse spinal motor neurons and selective herb extracts such as Epimedium Koreanum Nakai(EK) and Alpinia oxphylla Mig(IJI) were very effective in the increase of cell viability against the neurotoxicity induced by oxygen radicals in these cultures.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.233-238
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• 2002

Moxibustion is one of major healing technique in oriental medicine. It has been widely used in many diseases such as rheumatoid arthritis, Hashimoto disease, breech presentation, etc. However, till now, effects of moxibustion on NK cell activity and relations between sympathetic nerve system(SNS) and the immune alteration induced by moxibustion were not well studied. This study was designed to evaluate effects of moxibustion on NK cell activity and the intervention of SNS in the alteration of NK cell activity induced by moxibustion. Splenic NK cytotoxity was measured in a standard 4-h 51Cr release assay. We measured the NK cytotoxity at after moxibustion stimulation for 1,3,5, and 7 days, and also measured the NK cell cytotoxity after 3 and 7 days burn stimulation with similar temperature. IL-2, IL-4, INF-γ in serum were measured by rat IL-2, IL-4, INF-γ ELISA TEST KIT. To evaluate the effects of sympathectomy on alteration of NK cell cytotoxity, 6-hydroxydopamine(6-OHDA : 5Omg/kg) was used. We showed that NK cell activity of moxibustion stimulation group increased at the 3rd day, and declined at 7th day in comparison with that of contol group. In moxibustion stimulation group, NK cell activity of 3 day stimulation group was significantly higher than sham group. On the contrary, in burn stimulation group, NK cell activity was significantly higher than that of sham groups at 3rd, 7th days. Patterns between moxibustion and burns were different. INF- γ level of 3 days moxibustion stimulation group significantly higher than sham group. IL 2 level among groups were not different. IL-4 was not detected in serum with this method. Sympathectomy abolished the NK cell activity alteration induced by moxibustion. The results suggest that moxibustion induces the alteration of NK cell activity, along with INF-γ and SNS is related to these effects.

• BMB Reports
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• v.53 no.10
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• pp.491-499
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• 2020

The extracellular matrix is a critical component of every human tissue. ECM not only functions as a structural component but also regulates a variety of cellular processes such as cell migration, differentiation, proliferation, and cell death. In addition, current studies suggest that ECM is critical for the pathophysiology of various human diseases. ECM is composed of diverse components including several proteins and polysaccharide chains such as chondroitin sulfate, heparan sulfate, and hyaluronic acid. Each component of ECM exerts its own functions in cellular and pathophysiological processes. One of the interesting recent findings is that ECM is involved in inflammatory responses in various human tissues. In this review, we summarized the known functions of ECM in neuroinflammation after acute injury and chronic inflammatory diseases of the central nerve systems.

• Applied Microscopy
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• v.25 no.4
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• pp.9-16
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• 1995

Ultrastructure of stemmata(larval eye) of 5th-instar larval in cabbage butterfly, Pieris rapae L, was morphologically investigated with light microscope, scanning electron microscope and transmission electron microscope Six stemmata are on each side of the head. Stemmata V and VI have a Y-shaped sulcus on the surface of their corneal lenses, the others have a columnar shaped process and smooth globular surface. The visual type of stemmata is resembled a single ommatidium of compound eye. The dioptric apparatus are a biconvex shaped cornea and crystalline cone. As a photoreceptor, each stemmata consists of 7 retinular cells arranged into 2 tiers. The first ceil tier of 3 distal retinular cells has formed a V-shaped cup rhabdome and the second cell tier of 4 basal retinular cells has formed a H-shaped fused rhabdome. Each retinular cell filled with pigment granules and contained multivesiclular bodies, coated vesicle and common organelles. The peripheral parts of retinular cells are enveloped by neuroglia cells and retinular cells are surrounded by 3 corneagenous cells. The distal portions of the 3 corneagenous cells contact each other, but the Y-shaped stemmata is separated from each other immediately under the cornea. The 7 axons from each stemma congregate into a bundle and each 7-axon group joins to form a stemmatal nerve, consisting of 42 retinular axons.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.6
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• pp.455-461
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• 2000

Zinc contained in the neurons of central nervous system is activity-dependently released and then attenuates NMDA (N-methyl-D-aspartate)-induced neurotoxicity while augmenting non-NMDA-induced neurodegeneration. Zinc also has been reported to produce antinociceptive action on the inflammation- and nerve injury-induced hyperalgesia in the behavioral test. In this study, we investigated the effects of zinc on the responses of dorsal horn cells to NMDA, kainate and graded electrical stimulation of C-fibers. In the majority of WDR cells (70.6%), zinc current-dependently inhibited WDR cell responses to NMDA and in the remaining cells, produced biphasic responses; excitation followed by inhibition. Zinc augmented the responses of WDR cells to iontophoretical application of kainate. The dominant effect of $Zn^{2+}$ on the responses of WDR cells to C-fiber stimulation was excitatory, but inhibition, excitation-inhibition and no change of the responses to C-fiber stimulation were induced. $Ca^{2+}-EDTA$ antagonized the excitatory or inhibitory effects of $Zn^{2+}$ on the WDR cell responses. These experimental findings suggest that $Zn^{2+}$ modulates the transmission of sensory information in the rat spinal cord.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.349-359
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• 1994

To elucidate pathogenicity to hamster of encephalomyocarditis virus $K_3$ strain that was isolated in Korea from the swine with reproductive failures, adult male syrian hamsters were experimentally infected intraperitoneally with the virus at $10^{7.0}\;TCID_{50}/0.1ml$ and pathological and immunohistochemical studies were performed. The results obtained through the experiment were as follows. 1. Clinical signs such as depression, unkempt hair and bilateral parlysis of hind limbs were observed. 2. At necropsy, mild congestion was observed in the cerebrum, liver, kidney and lung, and atrophy was evident in testis. 3. In microscopic observation, degeneration and necrosis of the nervous cells and perivascular mononuclear cell infiltration were manifested in central nerve system, and various degrees of degeneration and necrosis of parenchymal cells were detected in pancreas, lacrimal gland, liver, kidney and testis. 4. In immunohistochemical observation, strong positive reactions were observed in degenerated parenchymal cell of testis, and weak positive reactions, in hepatocytes.