• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.52-66
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• 1983

The brown planthopper, N. lugens (Stal), has become a serious pest of rice in tropical Asia during the last decade. At high pest density, its feeding damage causes 'hopperburn' or complete wilting and drying of the rice plant. It also transmits grassy and ragged stunt virus diseases. The estimated losses caused by the pest in tropical Asia exceed $US\$300$ millions. While cultivation of resistant rice varieties has proved to be highly effective against the pest, their long-term stability is threatened because of the evolution of prolific biotypes which can destroy these varieties. At present, identification of biotypes is based principally on the differential reactions of host rice varieties to the pest and on host-mediated behavioral and physiological responses of the pest. Recent findings of morphological differences in adult rostrum, legs, and antennae, body parts that possess receptors for host plant location and discrimination, and cytological differences in N. lugens populations maintained as stock cultures strongly complement other biotype studies. So far, three N. lugens biotypes have been identified in the Philippines. Biotype I can survive on and damage varieties that do not carry and genes for resistance, while Biotype 2 survives on resistant varieties carrying Bph 1 gene and Biotype 3 on varieties carrying gene bph 2. However, none of these biotypes can survive on varieties with genes Bph 3 or bph 4. Several varieties which are resistant in the Philippines are susceptible in India and Sri Lanka as the South Asian biotypes of N. lugens are more virulent than Southeast Asian biotypes. To monitor the pest biotypes in different geographical regions and to identify new sources of resistance, an International Brown Planthopper Nursery has been established in many cooperating countries. The evolution of biotypes is an exceedingly complex process which is governed by the interactions of genetic and biological factors of the pest populations and the genetic makeup of the cultivated varieties. While the strategy for sequential release of varieties with major resistance genes has been fairly successful so far, the monegenic resistance of these varieties makes them vulnerable to the development of the pest biotypes. Therefore, present breeding endeavors envisage utilizing both major and minor resistance genes for effective control of the pest.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2004.06a
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• pp.60-61
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• 2004

Metabolic engineering is now a well established discipline, used extensively to determine and execute rational strategies of strain development to improve the performance of micro-organisms employed in industrial fermentations. The basic principle of this approach is that performance of the microbial catalyst should be adequately characterised metabolically so as to clearlyidentify the metabolic network constraints, thereby identifying the most probable targets for genetic engineering and the extent to which improvements can be realistically achieved. In order to harness correctly this potential, it is clear that the physiological analysis of each strain studied needs to be undertaken under conditions as close as possible to the physico-chemical environment in which the strain evolves within the full-scale process. Furthermore, this analysis needs to be undertaken throughoutthe entire fermentation so as to take into account the changing environment in an essentially dynamic situation in which metabolic stress is accentuated by the microbial activity itself, leading to increasingly important stress response at a metabolic level. All too often these industrial fermentation constraints are overlooked, leading to identification of targets whose validity within the industrial context is at best limited. Thus the conceptual error is linked to experimental design rather than inadequate methodology. New tools are becoming available which open up new possibilities in metabolic engineering and the characterisation of complex metabolic networks. Traditionally metabolic analysis was targeted towards pre-identified genes and their corresponding enzymatic activities within pre-selected metabolic pathways. Those pathways not included at the onset were intrinsically removed from the network giving a fundamentally localised vision of pathway functionality. New tools from genome research extend this reductive approach so as to include the global characteristics of a given biological model which can now be seen as an integrated functional unit rather than a specific sub-group of biochemical reactions, thereby facilitating the resolution of complexnetworks whose exact composition cannot be estimated at the onset. This global overview of whole cell physiology enables new targets to be identified which would classically not have been suspected previously. Of course, as with all powerful analytical tools, post-genomic technology must be used carefully so as to avoid expensive errors. This is not always the case and the data obtained need to be examined carefully to avoid embarking on the study of artefacts due to poor understanding of cell biology. These basic developments and the underlying concepts will be illustrated with examples from the author's laboratory concerning the industrial production of commodity chemicals using a number of industrially important bacteria. The different levels of possibleinvestigation and the extent to which the data can be extrapolated will be highlighted together with the extent to which realistic yield targets can be attained. Genetic engineering strategies and the performance of the resulting strains will be examined within the context of the prevailing experimental conditions encountered in the industrial fermentor. Examples used will include the production of amino acids, vitamins and polysaccharides. In each case metabolic constraints can be identified and the extent to which performance can be enhanced predicted

• Journal of Sericultural and Entomological Science
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• v.4
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• pp.41-46
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• 1965

Author investigated the effects of a grate type mounting on. the pupae, moth and deposit of silkworm eggs. The results are as follows. 1) The grate type mounting was more useful for the silkworms to spin the cocoons transversely than the other type. 2) Many abnormal pupae appeared in the control, and in next generation all the silkworm characters of them were poor. 3) The fact which many dead pupae occurred in the control seems to be that the cocoons spun vertical1y did harm to the physiological reactions of the pupae. 4) The moth rate emerging out of the cocoons was higher in the grate type mounting than in the control. 5) Many moths which laid normal eggs were in the grate type mounting, and also laid a lot of eggs. Therefor, author made an infference that the grate type mounting had accelerated the laying eggs. 7) The total weight of eggs produced from 1000 cocoons was heavier in the grate type mounting(index=100) than in the control (index=85). As shown in table of analysis of vanriace, above phenomenon might be relative with one of the reasons why the cocoon spun transversely could be more produced in the grate type mounting than in the control. 8) Even though the grate type mounting costs higher than the other one, it may be available because the egg weight per unit was considerably heavier in its treatment. So the cost of egg production will become cheaper.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.239-244
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• 2002

Okbyungpoongsan-Gami (OG) has been used for the treatment of excessive sweating with general weakness and allergic rhinitis recently. Anal therapy is another way of taking Oriental medicine. It is an important pathway but not available in common clinical situation. This experiment was performed in order to study the inhibitory effect of immediate-type allergic reaction of OG by anal therapy. In addition, the experiment was practised by 1 H-NMR spectroscopy to examine molecular structure of OG. The results were obtained as follows : OG concentration-dependently inhibited compound 48/80- induced immediate type systemic allergic reaction with concentrations of 0.01-1.0g/kg by anal administration 1 h before injection of compound 48/80. OG also concentration-dependently inhibited compound 48/80- induced ear swelling response with concentrations of 0.01-1g/kg by anal administration 1h before injection of compound 48/80. OG also inhibited the passive cutaneous anaphylaxis activated by anti-dinitrophenyl (DNP) IgE antibody concentration- dependently at concentrations ranging from 0.01 to 1g/kg. When OG was pretreated at concentrations ranging from 0.01 to 1g/ℓ, the histamine release from the rat peritoneal mast cells induced by compound 48/80 was reduced in a concentration-dependent manner. OG (0.1-1g/ℓ) had a significant inhibitory effect on histamine release from IgE-induced activated mast cells. OG is seen to be a biochemical compound certainly by 1 H-NMR spectroscopy According to above results, anal therapy of OG may be beneficial in the treatment of systemic and local immediate-type allergic reactions by inhibition of histamine release from mast cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1179-1185
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• 2004

The Korean traditional medicine, Seonghyangjeonggisan (SHJGS) has long been used for acute cerebral infarction (Cl). However, scientific investigation has been carried out a little. Cytokines, involved in the regulation of inflammatory reactions and immune responses, may play an important role in the pathogenesis of Cl. The aim of this study is to investigate the effects of SHJGS on the production of various cytokines in the patients with acute Cl. Peripheral blood mononuclear cells (PBMC) obtained from the patients with acute Cl were cultured for 24hr in the presence or absence of lipopolysaccharide (LPS) and phytohaemagglutinin (PHA). The amount of TNF-α, IL-1β, IL-6 and IL-8, in PBMC culture supernatant, was significantly increased in the LPS and PHA treated cells, compared with unstimulated cells (P<0.05). This study showed that increased TNF-α, IL-1β, IL-6 and IL-8 level stimulated by LPS and PHA was inhibited by SHJGS (0.01-1 ㎎/㎖) in a dose-dependent manner but IL-8 level was not inhibited significantly at 1㎎/㎖ (P>0.05). The maximal inhibition rate of TNF-α, IL-1β, IL-6 and IL-8 by SHJGS (1㎎/㎖) was 68% (P<0.05), 53.9% (P<0.05), 45.5% (P<0.05), 46.7% (P>0.05) respectively. These results suggest that SHJGS might have anti-inflammatory effects through cytokine modulation. which might explain its beneficial effects in the treatment of acute Cl.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.1
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• pp.83-91
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• 2013

Pruritus is a unpleasant symptom in the skin that provokes the act of or desire to scratch. Mast cells are important effector cells in allergic reactions such as pruritus and inflammation. The purpose of this study was undertaken to investigate the synergic anti-pruritic and anti-inflammatory effects of Scutellariae Radix (SB) plus Flos Loncerae (FL) extracts in rat peritoneal mast cells (RPMCs), pruritogen-induced scratching mice and 2,4-dinitrofluorobenzene (DNFB)-induced allergic mice. We investigated the effect of SB, FL and SB plus FL extracts on the production of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$, and histamine in RPMCs, on the scratching behavior in ICR mice, and skin clinical serverity and inflammatory mediators in DNFB-induced allergic hairless mice. RPMCs stimulated with PMA plus A23187 or compound 48/80 significantly increased TNF-${\alpha}$, IL-$1{\beta}$ or histamine production compared with media control. However, TNF-${\alpha}$ IL-$1{\beta}$ or histamine levels increased by PMA plus A23187 or compound 48/80 treatment were significantly inhibited by SB, FL in a dose-dependent manner. Especially, SB plus FL pretreatment had a synergic inhibitory effects on stimulator-induced cytokines (TNF-${\alpha}$ and IL-$1{\beta}$) and histamine production. Moreover, SB plus FL administration had a synergic inhibitory effects on the scratching behavior induced by pruritogen (compound 48/80, histamine, serotonin, substance P) in ICR mice. Furthermore, SB plus FL administration had a synergic inhibitory effects on skin damage, inflammatory mediators, leukocyte and mast cell infiltration induced by DNFB in hairless mice. These results suggest that SB plus FL administration has a potential use as a medicinal plant for treatment against itching and inflammation-related skin disease.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.101-108
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• 2006

YNB54 strain which shows inhibitory activities specific to the plant pathogenic Phytophthora sp. on potato dextrose agar medium was screened among lots of strains isolated from Korean soils. To identify taxonomy of the Phytophthora specific antagonistic bacteria YNB54, 165 rDNA sequence, MIDI fatty acid composition, DNA-DNA hybridization, GC content, and commercial multitest systems such as API 20E and Biolog GN were performed. Results of commercial kits including lots of biochemical and physiological reactions showed that this strain was closely related to taxa including Enterobacter cloacae and Enterobacter cancerogenus species than other genera(Citerobacter Klebsiella, Leclercia). Also, analysis of its MIDI, G+C contents, and DNA-DNA hybridization suggests that this strain was more similiar to the Genus Enterobacter than other genera (Citerobacter Klebsiella, Leclercia). This strain was potentially identified as Enterobacter sp. by these results. But our 16S ribosomal DNA sequences (rDNA) analysis confirmed that it was more closely related to the cluster of Citerobacter freundii ATCC 29935 than any other Enterobacter species. In the absence of defined phylogenetic critia for delineating genera, the results observed with Citrobacter and Enterobacter species suggest that further studies are needed to clarify their relationships. This investigation demonstrates that YNB54 strain is genetically diverse and potentially more taxonomically complex than hitherto realized. Further study is necessary to confirm their taxonomic positions.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.5
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• pp.1106-1115
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• 2009

Mori Ramulus has multiple applications in Korean traditional medicine prescription because it has antioxidant and anti-inflammatory effects by reducing macrophage activities. Yet, no studies on the anti-arthritic activity of EMR (extract of Mori Ramulus) have been reported in vitro and in vivo. Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic inflammation characterized by hyperplasia of synovial cells in affected joints, which ultimately leads to the destruction of cartilage and bone. Because collagen-induced arthritis (CIA) is similar to RA in pathological symptoms and immune reactions, there have been several reports concerning RA using CIA mouse model. Here, we investigated the effects of Mori Ramulus on RA using CIA mice. The importance of CD4+ Th1 cells in RA progress was previously indicated and studies further showed that Th17 cells play a prime role in severity of disease. Accordingly, the present study was focused on CIA associated with CD4+ Th1 cells and Th1 7 cells. DBA/1OlaHsd mice were immunized with bovine type II collagen (CII). After a second collagen immunization, mice were treated with EMR once a day for 4 weeks. The severity of arthritis within the paw joints was evaluated by histological assessment of cartilage destruction and pannus formation. Immune cells in peripheral blood mononuclear cells (PBMC), draining lymph node (DLN) and paw joints, cytokine production and gene expression were assessed from CIA mouse using ELISA, FACS and real-time PCR analysis. Administration of EMR significantly suppressed the progression of CIA and inhibited the production of TNF-$\alpha$, IL-6 and IL-17 in the serum. The erosion of cartilage was dramatically reduced in mouse knees after treatment with EMR. In conclusion, our results demonstrate that EMR significantly suppressed the progression of CIA and that this action was mediated by the decreased production of TNF-$\alpha$, IL-6, IL-17 and collagen II-specific antibody in the serum. EMR suppressed Th17 cells and reduced level of IL-6 via B cell suppression, and thus, the levels of autoantibodies produced from B cells were decreased. Furthermore, EMR suppressed NKT cells which directly stimulate B cells and develop imbalance of Th1/Th2 cell. Oral administration of EMR (100 mg/kg or 200 mg/kg) significantly suppressed the progression of CIA, which is comparable to that of methotrexate (MTX, 0.3 mg/kg) used as a positive control. We are currently studying the mechanism underlying the therapeutic role for EMR in CIA mice.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.2
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• pp.217-222
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• 2014

Lonicerae Flos containing formulation, Geumeumyoungji-tang (GYT), is an herbal prescription prepared using 5 different herbal drugs, namely, Lonicerae Flos, Ganoderma, Lactucae Herba, Xanthii Fructus, and Smilacis Rhizoma. This study was focused on the investigation of the pharmacological effects of GYT on allergic reactions. As the first step of the study, GYT was administered BALB/c mice which were sensitized by 2,4-dinitrofluorobenzene (DNFB). As the result GYT ameliorated dermatitis provoked by DNFB. The serum IgE level of the DNFB sensitized-mouse was significantly decreased when GYT was administered. In order to confirm the moderating effect of this prescription on allergic reaction, GYT was pretreated to human mast cells (HMC-1) before they were stimulated by phorbol-12-myristate 13-acetate plus calcium ionophore A23187 (PMACI). GYT suppressed secretion of inflammatory cytokines, interleukin (IL)-6 and IL-8, from HMC-1. Additionally, pretreatment of GYT showed regulating effect on COX-2 expression. Collectively, these findings provide insights into the pharmacological actions of GYT as a potential agent for treatment of allergic dermatitis.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.21-32
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• 2010

This study investigated the effects of contiguity and reading mode on cognitive load factors measured by Galvanic Skin Response(GSR). In this study two experimental conditions were imposed to participants to measure cognitive load with the high contiguity picture and low contiguity picture. Thirty-four college students participated to this experiment(experiment group=17, control group=17), and spilt-plot factorial design was applied to control individual difference in galvanic skin response. Tasks of this experiment were reading and summary. The dependent variables were skin conductance response, and perceived difficulty. The independent variables were the degree of contiguity of visual material(high contiguity vs. low contiguity). The major result of this study was identification of a significant difference of GSR with low contiguity condition. Indeed it was identified that more complex reading condition required more cognitive loads. This finding supported that different cognitive process might require different amounts of cognitive loads. For the further research, this study discussed the validity of applying physiological signals to assess cognitive loads and relationships the associated affective reactions.