• Journal of Korean Neurosurgical Society
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• v.30 no.3
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• pp.263-271
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• 2001

Objective : Glioblastomas, the most common type of primary brain tumors, are highly invasive and cause massive tissue destruction at both the tumor invading edges and in areas that are not in direct contact with glioma cells. As a result, patients with high-grade gliomas are faced with a poor prognosis. Such grim statistics emphasize the need to better understand the mechanisms that underlie glioma invasion, as these may lead to the identification of novel targets in the therapy of high grade gliomas. Protein kinase C(PKC) is a family of serine/threonine kinases and an important signal transduction enzyme that conveys signals generated by ligand-receptor interaction at the cell surface to the nucleus. PKC appears to be critical in regulating many aspects of glioma biology. The purpose of this study was to assess accurately the role of PKC in the invasion regulation of human gliomas based on hypothesis that protein kinase C(PKC) is functional in the process of glial tumor cell invasion. Method : To test this hypothesis, U-87 malignant glioma cell line intracellular PKC levels were up and down regulated and their invasiveness was tested. Intracellular PKC level was characterized using PKC activity assays. Invasion assays including barrier migration and spheroid confrontation were used to study the relationship between PKC concentration and invasiveness. Result : The cell line which were treated by PKC inhibitor tamoxifen and hypericin exhibited decreased PKC activity and decreased invasive abilities dose dependently both in matrigel invasion assay and tumor spheroid fetal rat brain aggregates(FRBA) confrontation assay. However, the cell line that was treated by PKC activator 12-O-tetradecanylphorbol-13acetate(TPA) did not exhibit increases in either PKC activity or invasive ability. Conclusion : These studies suggest that PKC may be a useful molecular target for the chemotherapy of glioblastoma and other malignancies and that a therapeutic approach based on the ability of PKC inhibitors may be helpful in preventing invasion.

• Radiation Oncology Journal
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• v.17 no.4
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• pp.299-306
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• 1999

Purpose : The human genetic disorder ataxia-telangiectasia (AT) is a multisystem disease characterized by extreme radiosensitivity. The recent identification of the gene mutated in AT, ATM, and the demonstration that it encodes a homologous domain of phosphatidylinositol 3-kinase (PI3-K), the catalytic subunit of an enzyme involved in transmitting signals from the cell surface to the nucleus, provide support for a role of this gene in signal transduction. Although ionizing radiation was known to induce c-fos transcription, nothing is known about how ATM or PKCI mediated signal transduction pathway modulates the c-fos gene transcription and gene expression. Here we have studied the effect of PKCI on radiation sensitivity and c-fos transcription in normal and AT cells. Materials and Methods: Normal (LM217) and AT (AT5BIVA) cells were transfected with PKCI expression plasmid and the overexpression and integration of PKCI was evaluated by northern blotting and polymerase chain reaction, respectively. 5 Gy of radiation was exposed to LM and AT cells transfected with PKCI expression plasmid and cells were harvested 48 hours after radiation and investigated apoptosis with TUNEL method. The c-fos transcription activity was studied by performing CAT assay of reporter gene after transfection of c-fos CAT plasmid into AT and LM cells. Results: Our results demonstrate for the first time a role of PKCI on the radiation sensitivity and c-fos expression in LM and AT cells. PKCI increased radiation induced apoptosis in LM cells but reduced apoptosis in AT cells. The basal c-fos transcription activity is 70 times lower in AT cells than that in LM cells. The c-fos transcription activity was repressed by overexpression of PKCI in LM cells but not in AT cells. After induction of c-fos by Ras protein, overexpression of PKCI repressed c-fos transcription in LM cells but not in AT cells Conclusion: Overexpression of PKCI increased radiation sensitivity and repressed c-fos transcription in LM cells but not in AT cells. The results may be a. reason of increased radiation sensitivity of AT cells. PKCI may be involved in an ionizing radiation induced signal transduction pathway responsible for radiation sensitivity and c-fos transcription. The data also provided evidence for novel transcriptional difference between LM and AT cells.

• Genomics & Informatics
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• v.16 no.2
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• pp.36-41
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• 2018

Kawasaki disease (KD) is an acute febrile vasculitis predominately affecting infants and children. The dominant incidence age of KD is from 6 months to 5 years of age, and the incidence is unusual in those younger than 6 months and older than 5 years of age. We tried to identify genetic variants specifically associated with KD in patients younger than 6 months or older than 5 years of age. We performed an age-stratified genome-wide association study using the Illumina HumanOmni1-Quad BeadChip data (296 cases vs. 1,000 controls) and a replication study (1,360 cases vs. 3,553 controls) in the Korean population. Among 26 candidate single nucleotide polymorphisms (SNPs) tested in replication study, only a rare nonsynonymous SNP (rs4365796: c.1106C>T, p.Thr369Met) in the lymphoid enhancer binding factor 1 (LEF1) gene was very significantly associated with KD in patients younger than 6 months of age (odds ratio [OR], 3.07; $p_{combined}=1.10{\times}10^{-5}$), whereas no association of the same SNP was observed in any other age group of KD patients. The same SNP (rs4365796) in the LEF1 gene showed the same direction of risk effect in Japanese KD patients younger than 6 months of age, although the effect was not statistically significant (OR, 1.42; p = 0.397). This result indicates that the LEF1 gene may play an important role as a susceptibility gene specifically affecting KD patients younger than 6 months of age.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.605-610
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• 2003

According to the Leukemia and Lymphoma Society, leukemia is a malignant disease (cancer) that originates in a cell in the marrow. It is characterized by the uncontrolled growth of developing marrow cells. There are two major classifications of leukemia: myelogenous or lymphocytic, which can each be acute or chronic. The terms myelogenous or lymphocytic denote the cell type involved. Thus, four major types of leukemia are: acute or chronic myelogenous leukemia and acute or chronic lymphocytic leukemia. Leukemia, lymphoma and myeloma are considered to be related cancers because they involve the uncontrolled growth of cells with similar functions and origins. The diseases result from an acquired (not inherited) genetic injury to the DNA of a single cell, which becomes abnormal (malignant) and multiplies continuously. In the United States, about 2,000 children and 27,000 adults are diagnosed each year with leukemia. Treatment for cancer may include one or more of the following: chemotherapy, radiation therapy, biological therapy, surgery and bone marrow transplantation. The most effective treatment for leukemia is chemotherapy, which may involve one or a combination of anticancer drugs that destroy cancer cells. Specific types of leukemia are sometimes treated with radiation therapy or biological therapy. Common side effects of most chemotherapy drugs include hair loss, nausea and vomiting, decreased blood counts and infections. Each type of leukemia is sensitive to different combinations of chemotherapy. Medications and length of treatment vary from person to person. Treatment time is usually from one to two years. During this time, your care is managed on an outpatient basis at M. D. Anderson Cancer Center or through your local doctor. Once your protocol is determined, you will receive more specific information about the drug(s) that Will be used to treat your leukemia. There are many factors that will determine the course of treatment, including age, general health, the specific type of leukemia, and also whether there has been previous treatment. there is considerable interest among basic and clinical researchers in novel drugs with activity against leukemia. the vast history of experience of traditional oriental medicine with medicinal plants may facilitate the identification of novel anti leukemic compounds. In the present investigation, we studied 31 kinds of anti leukemic medicinal plants, which its pharmacological action was already reported through many experimental articles and oriental medical book: 『pharmacological action and application of anticancer traditional chinese medicine』 In summary: Used leukemia cellline are HL60, HL-60, Jurkat, Molt-4 of human, and P388, L-1210, L615, L-210, EL-4 of mouse. 31 kinds of anti leukemic medicinal plants are Panax ginseng C.A Mey; Polygonum cuspidatum Sieb. et Zucc; Daphne genkwa Sieb. et Zucc; Aloe ferox Mill; Phorboc diester; Tripterygium wilfordii Hook .f.; Lycoris radiata (L Her)Herb; Atractylodes macrocephala Koidz; Lilium brownii F.E. Brown Var; Paeonia suffruticosa Andr.; Angelica sinensis (Oliv.) Diels; Asparagus cochinensis (Lour. )Merr; Isatis tinctoria L.; Leonurus heterophyllus Sweet; Phytolacca acinosa Roxb.; Trichosanthes kirilowii Maxim; Dioscorea opposita Thumb; Schisandra chinensis (Rurcz. )Baill.; Auium Sativum L; Isatis tinctoria, L; Ligustisum Chvanxiong Hort; Glycyrrhiza uralensis Fisch; Euphorbia Kansui Liou; Polygala tenuifolia Willd; Evodia rutaecarpa (Juss.) Benth; Chelidonium majus L; Rumax madaeo Mak; Sophora Subprostmousea Chunet T.ehen; Strychnos mux-vomical; Acanthopanax senticosus (Rupr.et Maxim.)Harms; Rubia cordifolia L. Anti leukemic compounds, which were isolated from medicinal plants are ginsenoside Ro, ginsenoside Rh2, Emodin, Yuanhuacine, Aleemodin, phorbocdiester, Triptolide, Homolycorine, Atractylol, Colchicnamile, Paeonol, Aspargus polysaccharide A.B.C.D, Indirubin, Leonunrine, Acinosohic acid, Trichosanthin, Ge 132, Schizandrin, allicin, Indirubin, cmdiumlactone chuanxiongol, 18A glycyrrhetic acid, Kansuiphorin A 13 oxyingenol Kansuiphorin B. These investigation suggest that it may be very useful for developing more effective anti leukemic new dregs from medicinal plants.

• Journal of Life Science
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• v.30 no.6
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• pp.555-562
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• 2020

This study analyzed the total polyphenol (TP), total flavonoid (TF), and protein content, the Absorbance at 400 nm (A400), and the antioxidant and hemolytic activities of 150 Korean honey products, including 41 chestnut (CH), 42 acacia (AH), 62 multi-floral (MH), and five Styrax japonica (TH) varieties. Our results showed that the components and antioxidant activities of honey are dependent on botanical origin rather than farming area or farmer. CH showed the highest levels of TP (88.6±29.8 mg/100 g) and TF (1.20±0.82 mg/100 g), whereas TH had the highest protein (21.5±5.1 mg/100 g). A400 was the highest in CH (0.161±0.044). All of the honey products exhibited negligible hemolytic activity against human red blood cells up to 1 mg/ml. Potent radical scavenging activities for 1,1-diphenyl-2-picryl hydrazyl (DPPH), 2,2-azobis(3-ethylbenzothiazoline-6- sulfonate) (ABTS), nitrite and reducing power were also observed in CH. Correlation coefficients (CCs) between analysis parameters were calculated and the highest was identified between TP and ABTS scavenging activity (0.726). The CCs between A400 and TP and A400 and ABTS scavenging activity were 0.644 and 0.661, respectively, suggesting that A400 could be used as a quality indicator for the polyphenol content and antioxidant activity of particular honeys. Future research on polyphenol by flower origin and the identification of compounds for A400 is necessary.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.49-58
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• 1984

The differential diagnosis of atypical mycobacteriosis caused by atypical mycobacteria (with the exception of Mycobacterium tuberculosis, Mycobacterium bovis, and Mycobacterium leprae) which are widly distributed in soil and water, from pulmonary tuberculosis is possible only when atypical mycobacteria are isolated and identified. In this investigation, attempts were made to isolate atypical mycobacteria from persons registered as tuberculosis patients in the Anyang Health Center in Anyang City, Kyungki province, Korea. Biological and biochemical tests were performed for the atypical mycobacteria isolated from these patients, also retrospective analysis of clinical and X-ray findings of the patients with bacteriologically confirmed atypical mycobacteriosis were done. The results can be summarized as follows: 1. 103 strains of mycobacteria were isolated among 334 sputum samples from patients. 2. Among the isolated mycobacteria, 10 strains (9.7%) were found to be a atypical mycobacteria and 93 strains (90.3%) were tubercle bacilli of human type. 3. On the basis of Runyon's grouping of atypical mycobacteria, there were 3 strains (30.0 %) of scotochromogen and nonphotochromogen respectively, 4 strains (40.0%) of rapid grower, and no photochromogen. 4. By biochemical tests, 3 strains of scotochromogen were identified as Mycobacterium scrofulaceum (2 strains) and Mycobacterium szulgai (1 strain) 3 strains of nonphotochromogen were Mycobacterium avium-complex (2 strains) and Mycobacterium terriae (1 strain), and 4 strains of rapid grower were Mycobacterium fortuitum (3 strains) and Mycobacterium chelonei. 5. In drug sensitivity tests, all 10 strains isolated atypical mycobacteria showed resistance to various concentration of INH and SM and low concentration (10mcg, 40mcg and 50mcg) of EB, TH, and CS, and were sensitive to only high concentration (20mcg and 100mcg) of EB, TH, CS, and RFP. 6. In analysis of clical findings by the patients with bacteriologically confirmed atypical mycobacteriosis, it was found that clinical symptoms of these patients appeared not to be mild than those of patients with pulmonary tuberculosis. The patients with atypical mycobacteriosis had been treated for pulmonary tuberculosis for a long time and they showed no improvement.

• Journal of Periodontal and Implant Science
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• v.37 no.sup2
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• pp.447-463
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• 2007

Periodontal ligament (PDL) cells have been known as multipotential cells, and as playing an important rolesin periodontal regeneration. The PDL cells are composed of heterogeneous cell populations which have the capacity to differentiate into either cementoblasts or osteoblasts, depending on needs and conditions. Therefore, PDL cells have the capacity to produce mineralized nodules in vitro in mineralization medium which include ascorbic acid, ${\beta}$-glycerophosphate and dexamethasone. In spite of these well-known osteoblast like properties of PDL cells, very little is known about the molecules involved in the formation of the mineralized nodules in the PDL cells. In the present study, we analysed gene-expression profiles during the mineralization process of cultured PDL cells by means of a cDNA microarray consisting of 3063 genes. Nodules of mineralized matrix were strongly stained with alizarin red S on the PDL cells cultured in the media with mineralization supplements. Among 3,063 genes analyzed, 35 were up-regulated more than two-fold at one or more time points in cells that developed matrix mineralization nodules, and 38 were down-regulated to less than half their normal level of expression. In accord with the morphological change we observed, several genes related to calcium-related or mineral metabolism were induced in PDL cells during osteogenesis, such as IGF-II and IGFBP-2. Proteogycan 1, fibulin-5, keratin 5, ,${\beta}$-actin, ${\alpha}$-smooth muscle actin and capping protein, and cytoskeleton and extracellular matrix proteins were up-regulated during mineralization. Several genes encoding proteins related to apoptosis weredifferentially expressed in PDL cells cultured in the medium containing mineralization supplements. Dkk-I and Nip3, which are apoptosis-inducing agents, were up-regulated, and Btf and TAXlBP1, which have an anti-apoptosis activity, were down-regulated during mineralization. Also periostin and S100 calciumbinding protein A4 were down-regulated during mineralization.

• Asia pacific journal of information systems
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• v.18 no.4
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• pp.57-81
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• 2008

Knowledge is an essential strategic weapon for sustaining competitive advantage and is the key determinant for organizational growth. When knowledge is shared and disseminated throughout the organization, it increases an organization's value by providing the ability to respond to new and unusual situations. The growing importance of knowledge as a critical resource has forced executives to pay attention to their organizational knowledge. Organizations are increasingly undertaking knowledge management initiatives and making significant investments. Knowledge sourcing is considered as the first important step in effective knowledge management. Most firms continue to make an effort to realize the benefits of knowledge management by using various knowledge sources effectively. Appropriate knowledge sourcing strategies enable organizations to create, acquire, and access knowledge in a timely manner by reducing search and transfer costs, which result in better firm performance. In response, the knowledge management literature has devoted substantial attention to the analysis of knowledge sourcing strategies. Many studies have categorized knowledge sourcing strategies into intemal- and external-oriented. Internal-oriented sourcing strategy attempts to increase firm performance by integrating knowledge within the boundary of the firm. On the contrary, external-oriented strategy attempts to bring knowledge in from outside sources via either acquisition or imitation, and then to transfer that knowledge across to the organization. However, the extant literature on knowledge sourcing strategies focuses primarily on large organizations. Although many studies have clearly highlighted major differences between large and small firms and the need to adopt different strategies for different firm sizes, scant attention has been given to analyzing how knowledge sourcing strategies affect firm performance in small firms and what are the differences between small and large firms in the patterns of knowledge sourcing strategies adoption. This study attempts to advance the current literature by examining the impact of knowledge sourcing strategies on small firm performance from a holistic perspective. By drawing on knowledge based theory from organization science and complementarity theory from the economics literature, this paper is motivated by the following questions: (1) what are the adoption patterns of different knowledge sourcing strategies in small firms (i,e., what sourcing strategies should be adopted and which sourcing strategies work well together in small firms)?; and (2) what are the performance implications of these adoption patterns? In order to answer the questions, this study developed three hypotheses. First hypothesis based on knowledge based theory is that internal-oriented knowledge sourcing is positively associated with small firm performance. Second hypothesis developed on the basis of knowledge based theory is that external-oriented knowledge sourcing is positively associated with small firm performance. The third one based on complementarity theory is that pursuing both internal- and external-oriented knowledge sourcing simultaneously is negatively or less positively associated with small firm performance. As a sampling frame, 700 firms were identified from the Annual Corporation Report in Korea. Survey questionnaires were mailed to owners or executives who were most erudite about the firm s knowledge sourcing strategies and performance. A total of 188 companies replied, yielding a response rate of 26.8%. Due to incomplete data, 12 responses were eliminated, leaving 176 responses for the final analysis. Since all independent variables were measured using continuous variables, supermodularity function was used to test the hypotheses based on the cross partial derivative of payoff function. The results indicated no significant impact of internal-oriented sourcing strategies while positive impact of external-oriented sourcing strategy on small firm performance. This intriguing result could be explained on the basis of various resource and capital constraints of small firms. Small firms typically have restricted financial and human resources. They do not have enough assets to always develop knowledge internally. Another possible explanation is competency traps or core rigidities. Building up a knowledge base based on internal knowledge creates core competences, but at the same time, excessive internal focused knowledge exploration leads to behaviors blind to other knowledge. Interestingly, this study found that Internal- and external-oriented knowledge sourcing strategies had a substitutive relationship, which was inconsistent with previous studies that suggested complementary relationship between them. This result might be explained using organizational identification theory. Internal organizational members may perceive external knowledge as a threat, and tend to ignore knowledge from external sources because they prefer to maintain their own knowledge, legitimacy, and homogeneous attitudes. Therefore, integrating knowledge from internal and external sources might not be effective, resulting in failure of improvements of firm performance. Another possible explanation is small firms resource and capital constraints and lack of management expertise and absorptive capacity. Although the integration of different knowledge sources is critical, high levels of knowledge sourcing in many areas are quite expensive and so are often unrealistic for small enterprises. This study provides several implications for research as well as practice. First this study extends the existing knowledge by examining the substitutability (and complementarity) of knowledge sourcing strategies. Most prior studies have tended to investigate the independent effects of these strategies on performance without considering their combined impacts. Furthermore, this study tests complementarity based on the productivity approach that has been considered as a definitive test method for complementarity. Second, this study sheds new light on knowledge management research by identifying the relationship between knowledge sourcing strategies and small firm performance. Most current literature has insisted complementary relationship between knowledge sourcing strategies on the basis of data from large firms. Contrary to the conventional wisdom, this study identifies substitutive relationship between knowledge sourcing strategies using data from small firms. Third, implications for practice highlight that managers of small firms should focus on knowledge sourcing from external-oriented strategies. Moreover, adoption of both sourcing strategies simultaneousiy impedes small firm performance.

• Analytical Science and Technology
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• v.17 no.3
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• pp.199-210
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• 2004

A new polystyrene-divinylbenzene chelating resin containing 4,5-dihydroxy-naphthalene-2,7-disulfonic acid (chromotropic acid : CTA) as functional group has been synthesized and characterized. The sorption and desorption properties of this chelating resin for Cr(III) ion and Cr(VI) ion including nine metal bloodstain. As a results, FOB test kit could be effectively applied to identification of human blood at chelating resin was stable in acidic and alkaline solution. The Cr(VI) ion is selectively separated from Cr (III) ion at pH 2 and the maximum sorption capacity of Cr(VI) ion is 1.2 mmol/g. In the presence of anions such as $F^-$, $SO{_4}^{2-}$, $CN^-$, $CH_3COO^-$, $NO{_3}^-$, the sorption of Cr(VI) ion was reduced but anions such as $PO{_4}^{3-}$ and $Cl^-$ revealed no interference effect. The elution order of metal ions obtained from breakthrough capacity and overall capacity at pH 2 was Cr(VI)>Sn(II)>Fe(III)>Cu(II)>Cd(II)${\simeq}Pb(II){\simeq}Cr(III){\simeq}Mn(II){\simeq}Ni(II){\simeq}Al(III)$. Desorption characteristics for Cr(VI) ion was investigated with desorption agents such as $HNO_3$, HCl, and $H_2SO_4$. It was found that the ion showed high desorption efficiency with 3 M HCl. As the result, the chelating resin, XAD-16-CTA was successfully applied to separation and preconcentration of Cr (VI) ion from several metal ions in metal finishing works.

• The Journal of Dong Guk Oriental Medicine
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• v.8 no.2
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• pp.131-154
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• 2000

Nan Jing(Difficult Classic), as a catechism, describes in detail and deeply the ideas in Nei Jing(Huangdi's Internal Classic). The description of Nan Jing is focused on basic theories including theories about some disease and is excellent in identification and analysis. The contents of Nan Jing are as follows: 1-23 Nan-pulse and pulse condition, 24~29 Nan-channels and collaterals, 30~47 Nan-viscera and bowels(Zang Fu organs), 48~61 Nan-disease, 62~68 Nan-acupuncture points, 69~91 Nan-acupuncture. Especially, diagnosis techniques in Nan Jing make 'Only method of cunkou pulse taking' that is a technique for feeling the pulse widely applied in these days in Oriental medicine clear. Thus, this book adjusts the theory of pulse and pulse condition given in 1~23 Nan of 'The Study of Nan Jing' in order to enhance an understanding about the theory of pulse and pulse condition. The text of 1~23 Nan about pulse lore centers on all pulse of human body interconnected each other and cunkou, both ends of the pulse, and contrasts regular pulse with irregular pulse. 1. 10 Nan describes the theory about five kinds of evils and hardness and softness, and unique pulse condition of each bowels. 2. 13 Nan explains that the relative difficulty of medical treatment is determined by the degree of balance or unbalance among three factors-colors, pulse and pulse condition, flesh shape. 3. 14 Nan divides pulse and pulse condition into slow pulse and rapid pulse, and explains separately abnormality, great loss of semen, death caused by slow pulse, and abnormality, great loss of semen, death caused by rapid pulse. 4. 15 Nan about taut pulse(弦), full pulse(鉤), floating pulse(毛), deep pulse(石脈) describes that pulse and pulse condition differs according to four seasons. Therefore, Nan Jing establishes clearly techniques of feeling the pulse in 'Only method of cunkou pulse taking(獨取寸口)' and advances the theory of Nei Jing. Futhermore, Nan Jing is more valuable in that it suggests unique theory different with Nei Jing.