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Comparative Histological Study on the Parafollicular Cells of Mammals (각종 포유동물 갑상선내의 소포방세포에 관한 비교조직학적 연구)

  • 고정식;박상윤
    • The Korean Journal of Zoology
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    • v.23 no.2
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    • pp.89-108
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    • 1980
  • Comparative studies on the parafollicular cells of the some mammalian species from five different orders were carried out; i.e., man from Primates, cattle, pig, and black goat from Artiodactyla, dog from Carnivora, rabbit from Lagomorpha, rat, mouse, and squirrel from Rodentia. For this study, various special techniques for the parafollicular cells, including Grimelius' silver impregnation method (Sawicki and Bajko, 1974), Singh's argentaffin method (Singh, 1964), HCl-toluidine blue stain (Sawicki, 1971), and HCl-lead hematoxylin stain (Solcia et al., 1969), were applied. Authors obtained the following results: 1. Number of parafollicular cells in the same area of thyroid tissues are significantly different from species to species. Number of cells were largest in dog and less cells were found in the following orders; rat, squirrel, mouse, rabbit, cattle, pig, black goat and finally the smallest number in man. 2. Distribution of parafollicular cells within thyroid gland are significantly different from portion to portion in case of cattle, rabbit, squirrel and mouse, but it is not significant in dog, man, pig, black goat and rat (see Table 1-1 and 1-2). 3. In dog, clustered parafollicular cells are located usually in the interfollicular space, and groups of parafollicular cells are located in the para-and/or inter-follicular positions in rabbit. But in the other animals parafollicular cells are found solitarily in the intra-and/or para-follicular positions. 4. The shape of parafollicular cells shows oval to round contour in dog, but it is polymorphic, for example, spindle, conical, oval, round or elongated with cytoplasmic processes, in the other animals. 5. Size of parafollicular cells is larger in cattle, dog and pig, smaller in rat, mouse and squirrel, and medium-size in rabbit, man and black goat. 6. Parafollicular cells of pig, cattle, dog and squirrel are observed to contain densely packed granules, whereas those of mouse, rat and man contain relatively scanty granules. 7. Parafollicular cells of all the mammals show more or less positive reaction to Grimelius' argyrophile silver impregnation method, HCl-toluidine blue stain and HCl-lead hematoxylin stain, whereas they show negative reaction to argentaffin method (see Table 2). 8. Considering the above finding, it is concluded that there are species differences in the distribution, location and shape of parafollicular cells, and infer that preferable staining method should be selected for reliable detection of parafollicular cells, beacuse staining methods applied on the cells in this study show variable reactions according to species.

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Seasonal Prevalence of Mosquitoes Collected with Light Trap - At a Pig Shed in the Vicinity of Daegu City, Korea- (誘蚊燈에 捕獲된 모기類의 季節的 發生消長: 大邱市隣近 한 豚舍를 對象으로)

  • 孫錫洛
    • The Korean Journal of Zoology
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    • v.27 no.2
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    • pp.117-125
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    • 1984
  • Mosquitoes were collected with light trap at a pig shed in the vicinity of Daegu city from mid-April to the end of November in 1981 and 1982. A total of 12,942 and 118,061 individuals were collected in 1981 and 1982 respectively. The collection comprised 77% females and 23% males in 1981, and 96% females and 4% males in 1982. The catches were classified into following 7 species: Culex (Culex) pipiens pallens, C. (C.) tritaeniorhynchus summorosus, Anopheles (Anopheles) sinensis, C. (C.) vagans, C. (C.) oritntelis, C. (C.) bitaeniorhynchus, Aedes (Aedimorphus) vexans nipponii. The former three species showed distinct seasonal prevalence. Arranged in the descending order in size of the catches, in 1981, Culex (Culex) pipiens pallens was 44.9% of the total collection (at sex ratio of 0.85), Anopheles (Anopheles) sinensis 42.9% (0.05), Culex (Culex) tritaeniorhynchus summorosus 12.1% (0.00). On the contrary, Culex (Culex) tritaeniorhynchus summorosus 70.4% (0.00), Anopheles (Anopheles) sinensis 25.2% (0.05), Culex (Culex) pipiens pallens 4.4% (2.19) in 1982. The monthly percentages of collected mosquitoes to the total collection were 0.1% (in 1981) and 0.0% (in 1982) in May; 3.5%, 1.3% in June; 50.0%, 33.9% in July; 37.1%, in August; 8.8%, 11.9% in September; 0.5%, 0.8% in October and 0.0% in November. As for seasonal prevalence, mosquitoes appeared in May in both years and began to increase in number from the first week of June in 1981, but from the second week of May, ahead of three weeks in 1982. The highest peak time in 1982 was the second week of August, two weeks later than the fifth week of July in 1981. Culex (Culex) pipiens pallens showed the maximum activity for the fifth week of July in 1981, but for the third week of July, ahead of two weeks in 1982. Culex (Culex) tritaeniorhynchus reached the highest peak for the second week of August in both years. Anopheles (Anopheles) sinensis showed the maximum activity for the fifth week of July in 1981, but for the third week of July, two weeks earlier in 1982. The highest peak times of three main species were compared respectively as folows. Culex (Culex) pipiens pallens had the highest peak time in common with Anopheles (Anopheles) sinensis, Culex (Culex) tritaeniorhynchus summorosus showed the maximum activity for the second week of August in 1982.

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Establishment of the expression system of human HtrA2 in the zebrafish (Zebrafish 동물모델에서 human HtrA2의 expression system 정립에 관한 연구)

  • Cho, Sung-Won;Park, Hyo-Jin;Kim, Goo-Young;Nam, Min-Kyung;Kim, Ho-Young;Ko, In-Ho;Kim, Cheol-Hee;Rhim, Hyang-Shuk
    • Journal of Life Science
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    • v.16 no.4
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    • pp.571-578
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    • 2006
  • HtrA2/Omi, a mitochondrial trypsin-like serine protease, is pivotal in regulating apoptotic cell death. Several lines of recent evidence suggest that HtrA2 is associated with the pathogenesis of neurodegenerative disorders; however, the physiological function of HtrA2 still remains elusive. For studying physiological function of HtrA2 in depth, it is necessary to develop a suitable expression system in the model animal. We therefore utilized the zebrafish as a model animal to establish expression of human HtrA2 (hHtrA2) in vivo. For expression of mature HtrA2 as GFP fusion in zebrafish embryos, the HtrA2 (WT) or (S306A) cDNAs with the C-terminal GFP tag were inserted into the pCS2+ plasmid. Expression patterns of HtrA2 in HEK293 cells were first monitored by immunofluorescence staining and immunoblot assays, showing approximately 64 kDa of the HtrA2-GFP fusion proteins. Subsequently, the hHtrA2 plasmid DNA or in vitro transcribed mRNA was microinjected into zebrafish embryos. The expression patterns of HtrA2 in Zebrafish embryos were monitored by GFP fluorescence in 24 hours-post-fertilization (hpf). Although expression patterns of HtrA2-GFP in developing embryos were different between the injected DNA and mRNA, both nucleic acids revealed good expression levels to further study the physiological role of HtrA2 in vivo. This study provides a suitable condition for expressing hHtrA2 in the zebrafish embryos as well as a method for generating useful system to investigate physiological properties of the specific human genes.

Construction of Gene Network System Associated with Economic Traits in Cattle (소의 경제형질 관련 유전자 네트워크 분석 시스템 구축)

  • Lim, Dajeong;Kim, Hyung-Yong;Cho, Yong-Min;Chai, Han-Ha;Park, Jong-Eun;Lim, Kyu-Sang;Lee, Seung-Su
    • Journal of Life Science
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    • v.26 no.8
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    • pp.904-910
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    • 2016
  • Complex traits are determined by the combined effects of many loci and are affected by gene networks or biological pathways. Systems biology approaches have an important role in the identification of candidate genes related to complex diseases or traits at the system level. The gene network analysis has been performed by diverse types of methods such as gene co-expression, gene regulatory relationships, protein-protein interaction (PPI) and genetic networks. Moreover, the network-based methods were described for predicting gene functions such as graph theoretic method, neighborhood counting based methods and weighted function. However, there are a limited number of researches in livestock. The present study systemically analyzed genes associated with 102 types of economic traits based on the Animal Trait Ontology (ATO) and identified their relationships based on the gene co-expression network and PPI network in cattle. Then, we constructed the two types of gene network databases and network visualization system (http://www.nabc.go.kr/cg). We used a gene co-expression network analysis from the bovine expression value of bovine genes to generate gene co-expression network. PPI network was constructed from Human protein reference database based on the orthologous relationship between human and cattle. Finally, candidate genes and their network relationships were identified in each trait. They were typologically centered with large degree and betweenness centrality (BC) value in the gene network. The ontle program was applied to generate the database and to visualize the gene network results. This information would serve as valuable resources for exploiting genomic functions that influence economically and agriculturally important traits in cattle.

Apoptotic Cell Death by Pectenotoxin-2 in p53-Deficient Human Hepatocellular Carcinoma Cells (종양억제유전자 p53 결손 인체간암세포에서 Pectenotoxin-2에 의한 Apoptosis 유도)

  • Shin, Dong-Yeok;Kim, Gi-Young;Choi, Byung-Tae;Kang, Ho-Sung;Jung, Jee-H.;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1447-1451
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    • 2007
  • Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.

Characterization and Purification of the Bacteriocin Produced by Bacillus licheniformis Isolated from Soybean Sauce (간장에서 분리한 Bacillus licheniformis가 생산하는 박테리오신의 특성 및 정제)

  • Jung, Sung-Sub;Choi, Jung-I;Joo, Woo-Hong;Suh, Hyun-Hyo;Na, Ae-Sil;Cho, Yong-Kweon;Moon, Ja-Young;Ha, Kwon-Chul;Paik, Do-Hyeon;Kang, Dae-Ook
    • Journal of Life Science
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    • v.19 no.7
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    • pp.994-1002
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    • 2009
  • A bacteriocin-producing bacterium identified as Bacillus licheniformis was isolated from soybean sauce. Antibacterial activity was confirmed by paper disc diffusion method, using Micrococcus luteus as a test organism. The bacteriocin also showed antibacterial activities against Bacillus sphaericus, Lactobacillus bulgaricus, Lactobacillus planiarum, Paenibacillus polymyxa, and Pediococcus dextrinicus. Optimal culture conditions for the production of bacteriocin was attained by growing the cells in an MRS medium at a pH of 6.5~ 7.0 and a temperature of 37$^\circ$C for 36$\sim$48 hr. Solvents such as chloroform, ethanol, acetone, and acetonitrile had little effect on bacteriocin activity. However, about 50% of bacteriocin activity diminished with treatment of methanol and isopropanol at the final concentration of 50% at 25$^\circ$C for 1 hr. It was stable against a pH variation range from 3.0 and 7.0, but the activity reduced to 50% at a pH range from 9.0 to 11.0. It's activity was not affected by heat treatment at 100$^\circ$C for 30 min and 50% of activity was retained after heat treatment at 100$^\circ$C for 60 min, showing high thermostability. The bacteriocin was purified to a homogeneity through ammonium sulfate precipitation, SP-Sepharose ion-exchange chromatography, and reverse-phase high-performance liquid chromatography (HPLC). The entire purification protocol led to a 75-fold increase in specific activity and a 13.5% yield of bacteriocin activity. The molecular weight of purified bacteriocin was estimated to be about 2.5 kDa by tricine-SDS-PAGE.

Photosynthetic and Growth Responses of Chinese Cabbage to Rising Atmospheric CO2 (대기 중 CO2 농도의 상승에 대한 배추의 광합성과 생장 반응)

  • Oh, Soonja;Son, In-Chang;Wi, Seung Hwan;Song, Eun Young;Koh, Seok Chan
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.4
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    • pp.357-365
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    • 2016
  • The effects of elevated atmospheric $CO_2$ on photosynthesis and growth of Chinese cabbage (Brassica campestris subsp. napus var. pekinensis) were investigated to predict productivity in highland cropping in an environment where $CO_2$ levels are increasing. Vegetative growth, based on fresh weight of the aerial part, and leaf characteristics (number, area, length, and width) of Chinese cabbage grown for 5 weeks, increased significantly under elevated $CO_2$ ($800{\mu}mol{\cdot}mol^{-1}$) compared to ambient $CO_2$ ($400{\mu}mol{\cdot}mol^{-1}$). The photosynthetic rate (A), stomatal conductance ($g_s$), and water use efficiency (WUE) increased, although the transpiration rate (E) decreased, under elevated atmospheric $CO_2$. The photosynthetic light-response parameters, the maximum photosynthetic rate ($A_{max}$) and apparent quantum yield (${\varphi}$), were higher at elevated $CO_2$ than at ambient $CO_2$, while the light compensation point ($Q_{comp}$) was lower at elevated $CO_2$. In particular, the maximum photosynthetic rate ($A_{max}$) was higher at elevated $CO_2$ by 2.2-fold than at ambient $CO_2$. However, the photosynthetic $CO_2$-response parameters such as light respiration rate ($R_p$), maximum Rubisco carboxylation efficiency ($V_{cmax}$), and $CO_2$ compensation point (CCP) were less responsive to elevated $CO_2$ relative to the light-response parameters. The photochemical efficiency parameters ($F_v/F_m$, $F_v/F_o$) of PSII were not significantly affected by elevated $CO_2$, suggesting that elevated atmospheric $CO_2$ will not reduce the photosynthetic efficiency of Chinese cabbage in highland cropping. The optimal temperature for photosynthesis shifted significantly by about $2^{\circ}C$ under elevated $CO_2$. Above the optimal temperature, the photosynthetic rate (A) decreased and the dark respiration rate ($R_d$) increased as the temperature increased. These findings indicate that future increases in $CO_2$ will favor the growth of Chinese cabbage on highland cropping, and its productivity will increase due to the increase in photosynthetic affinity for light rather than $CO_2$.

The Diversity of Reproductive and Foraging Behaviors on Breeding Season of Eurasian Oystercatcher (Haematopus ostralegus) (검은머리물떼새의 번식행동 및 번식기 섭식행동의 다양성)

  • Yoon, Moo-Boo
    • The Korean Journal of Ecology
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    • v.27 no.6 s.122
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    • pp.383-390
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    • 2004
  • This study was conducted in three sites, Si-Hwa Lake, Dongman and Seoman island and Janguyeop island, from march, 1999 to september, 2002. The behaviors of pre-breeding season, territorial behaviors, reproductive ecology, foraging sites and behaviors, and the competition of reproduction and foods between intraspecific or interspecific of Eurasian Oystercatcher (Haematopus ostralegus) were observed in each studying sites. The breeding of Eurasian Oystercatcher started on the middle of April in Si-Hwa Lake and on the middle of May in Dongman and Seoman island and Janguyeop island. For intension of pair bond on pre-breeding season, Eurasian Oystercatcher foraged with pair and behaved male-female chasing flight behavior. The pair foraged with male and female before copulation. If other pairs and individuals approached in feeding site of pair, this pair attacked them with piping calling and intruder chasing flight. If continuos serial behaviors were not observed, the discrimination of male-female chasing flight and intruder chasing flight was difficult. Territorial behaviors classified four types; butterfly flight, calling behavior, chasing behavior, fight behavior. The important foraging sites in Si-Hwa Lake are the land place in Daeboo island, tidal flat of Bangameori, tidal flat a front of a stationary net for catching fishes and tidal flat a front of a view station for bird watching. Eurasian Oystercatcher foraged at tidal flat on low water of the tide and foraged at feeding sites near island on flood tide in Dongman and Seoman island. Eurasian Oystercater in Janguyeop island usually foraged feeding sites near island, because water level was not different between low water of the tide and flood tide. Eurasian Oystercatcher competed on foods of intraspecific and interspecific. They chased for taking foods by force in feeding sites and drove out intruders in feeding sites. The foods interspecific competition happened with Black-tailed Gull (Larus crassirostris). Eurasian Oystercatcher was robbed of foods and attacked by Black-tailed Gull. The individual of food competition with Black-tailed Gull was low foods intake rate comparison with other feeding sites and this individual flied out other feeding sites.

Protective Effect of a Herbal Preparation (HemoHIM) on the Self-Renewal Tissues and Immune System against γ-Irradiation (방사선에 대한 생약복합조성물(HemoHIM)의 재생조직 및 면역계 방호 · 회복촉진 효과)

  • Jo, Sung-Kee;Park, Hae-Ran;Jung, Uhee;Oh, Heon;Kim, Sung-Ho;Yee, Sung-Tae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.6
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    • pp.805-813
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    • 2005
  • In our previous study, a novel herb mixture (HIM-I) of Angelim gigas radix, Cnidium officinale rhizoma, and Paeonia japonica radix was developed to protect the intestinal and immune systems and promote its recovery against radiation damage. In this study, a new herbal preparation (HemoHIM) with the high immune modulating activity was developed from HIM-I. HIM-I was fractionated into ethanol fraction (HIM-I-E) and polysaccharide fraction (HIM-I-P). And HemoHIM was prepared by adding HIM-I-P to HIM-I. The protective activities against $\gamma$ -irradiation were compared among HemoHIM, HIM-I and the fractions. HemoHIM and HIM-I significantly decreased the radiation-induced DNA damage in vitro, and scavenged hydroxyl radicals in a dose-dependent manner. HemoHIM showed similar activity to HIM-I. In vitro proliferation assay with mouse lymphocytes and bone marrow cells showed that HIM-I-P was remarkably higher than HIM-I and HIM-I-E in cell proliferating activity. HemoHIM showed higher activity than HIM-I and this might be associated with the higher polysaccharide content. The in vivo protective effects of HemoHIM and HIM-I were investigated in $\gamma$-irradiated mice. HemoHIM increased the surviving intestinal crypts to a similar extent compared with HIM-I. In contrast, HemoHIM appeared to be more effective than HIM-I in endogenous spleen colony formation assay. The recovery of white blood cells and lymphocytes in irradiated mice were significantly enhanced by the administration of HemoHIM. Also HemoHIM administration prolonged the survival of irradiated mice. These results showed that the novel herbal preparation, HemoHIM, effectively protected the self-renewal tissues and immune system, and promoted the survival of irradiated mice. Moreover, in comparison with HIM-I, HemoHIM maintained similar activity in the reduction of oxidative damage of self-renewal tissue but exhibited the higher activity in protection and proliferation of immune and hematopoietic cells. These results suggested that HemoHIM might be more effective than HIM-I in immune modulation as well as radioprotection.

Early Responses of Planted Quercus serrata Seedlings and Understory Vegetation to Artificial Gap Treatments in Black Locust Plantation (아까시나무림에서 인공 숲틈 처리에 대한 졸참나무 식재목 및 하층식생의 초기 반응)

  • Cho, Yong-Chan;Kim, Jun-Soo;Lee, Jung-Hyo;Lee, Heon-Ho;Ma, Ho-Seob;Lee, Chang-Seok;Cho, Hyun-Je;Bae, Kwan-Ho
    • Journal of Korean Society of Forest Science
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    • v.98 no.1
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    • pp.94-105
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    • 2009
  • Black locust (Robinia pseudoacacia) stand is representative lowland exotic plantation with low ecological quality and arrested succession in South Korea. To facilitate succession and restore natural vegetation, small canopy gaps (${\sim}57m^2$), which can modify minimally structural variables and reduce restoration related disturbances on stand, was established in the black locust stand, and oak (Quercus serrata) seedlings were introduced in the gap. Two types of varying levels were introduced for gap creation; cutting (C) and girdling (G) on canopies. Understory removal (CU and GU) treatment was applied as subtypes of structural modification. Growth (diameter, height and leaf area) of target species and responses (species composition, diversity and coverage) of understory community were monitored during study years (2007~2008). Canopy openness was different significantly among treatments but not for light availability. Based on the result of logistic regression, growth of height and leaf area of seedlings were significant variables on seedling survival. Height and leaf area of seedlings were increased during study years, although radial growth was reduced. During study years, there were no significant differences in species composition and diversity, and total coverage increased about 20%. Increase of resources by gap creation and understory removal likely affect growth of target species. Small gap creation was effective to reduce understory responses in composition and diverstiy. Synthesized, growth of target species and responses of understory community to small canopy gap creation exhibited, in short term, possibility of utilization in alternative forest restoration and management option. Long-term monitoring is necessary to certificate effect of artificial gap creation on forest restoration.