• 한국균학회지
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• 제25권4호통권83호
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• pp.320-329
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• 1997

병든 오이, 토마토, 딸기로부터 분리한 Botrytis cinerea을 Paul(1928)의 형태형(morphological phenotypes) 분류 기준에 따라 포자형, 균핵형, 균사형으로 나눌 때 대부분의 균주는 균핵형으로 나타났다. Benzimidazole 및 dicarboximide계 살균제에 대한 감수성 및 저항성 반응 차이는 형태형과는 무관하였다. 포자의 표면 구조를 주사형 전자현미경으로 관찰한 결과 모두 봉상으로 형태형 간에 차이가 없었다. 형태형 간 병원성을 비교할 때, 균사형의 균주가 가장 병원성이 높았으며, 포자형은 병원성이 다른 형보다 낮게 나타났다. 병원성과 곰팡이의 phenol oxidase, pectin methyl esterases (PME), amylases, cellulases, ureases, glucosidases 및 proteinases 활성과의 관계를 조사하기 위하여 형태형이 다른 선발된 균주들의 효소 활성을 조사한 결과, Phenol oxidase, ${\beta}-glucosidase$는 각 형태형 간에 차이가 없었으나, PME, amylase, cellulase, urease, proteinase의 활성은 각 형태형간에 차이를 나타내어 병원성과 이들 효소 활성의 관련성이 있었다.

• 한국잔디학회:학술대회논문집
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• 한국잔디학회 2002년도 제15차 한국잔디학회 정기총회 및 춘계학술발표회
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• pp.3-5
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• 2002

This study was carried out to get better understandings about morphological, ecological, and genetical characteristics of annual bluegrass collected from different golf courses in Korea and eventually to establish a successful control strategy. Twenty five local lines of annual bluegrass collected from 20 golf courses in Korea were classified into annual or perennial type on the basis of morphological characteristics. Twelve local lines showing obvious morphological differences were selected and then genetically assessed using RAPD analysis. Classification of the 12 local lines through RAPD analysis were considerably similar to that determined by both of morphological differences and phenotype. Responses of the two types of annual blugrass to herbicides were also examined. Shoot growth of annual bluegrass was significantly suppressed by flazasulfuron and the annual type was more susceptible than perennial type, regardless of flazasulfuron concentrations used. By pendimethalin treatment, there was no clear difference in susceptibility between the two types of annual bluegrass. However, by the treatment of dithiopyr, annual type was more sensitive than perennial type in both shoot and root growth. Nine tree species were screened to detect their allelopathic potential on turfgrasses and annual bluegrass. Acacia (Robinia pseudo-acacia) leaves showed selective inhibition in the shoot and root growth as well as their seed germination when treated with 2% and 10%(v/v) of the extract. However, the other leaf extracts except acacia inhibited non-selectively the growth of three turfgrass species such as bentgrass, perennial ryegrass and zoysiagrass and annual bluegrass. The PAL activities of annual bluegrass increased at 24 h after treatment of acacia leaf extract and peaked at 36 h and then decreased till 60h. The highest PAL activity was observed at 36h after treatment of 10%. The highest activity of CA4H in annual bluegrass was observed at 2h after treatment of acacia extract and the level was 4 times greater than that of the control. The phenolic acids such as p-coumaric acid, salicylic acid and ferulic acid were increased with the treatment of acacia leaf extract. The chloroplast membrane and cell wall of annual bluegrass were destroyed by treatment of acacia leaf extract and its inner materials were released. The membranes in annual bluegrass cells might be destroyed by phytotoxic compounds from acacia leaf extract.

• 대한수의학회지
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• 제27권1호
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• pp.53-60
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• 1987

This experiment was performed on mice to investigate the effects of an immunopotentiator, picibanil(PC), on the immune responses such as phagocytic activity of reticuloen-dothelial(RE) system, E rosette formation rate of splenic lmphocytes and morphological changes of lymph node tissue. Groups of mice were treated with a single(1KE/kg BW) or sequential(0.1, 0.25 and 0.5KE/kg BW for successive 3 days) intravenous injections of PC. PC treated and untreated control mice were sensitized with 50% sheep erythrocyte suspension(0.2ml/mouse) at 1, 3, 5, 7 and 10 days after PC treatment. Functional and morphological examinations were carried out 5 days after sensitization. The following results were obtained: The phagocytic activity of RE system and the weight of liver and spleen were increased significantly at 3rd, 5th and 7th day. The peripheral polymorphonuclear leukocyte and percent of lymphocyte and monocyte were slightly increased. The rates of E rosette formation of splenic lymphotytes, sequential PC treated groups were more increased at 3rd and 5th day in sequential PC treated groups than in single treated groups. Thereafter it returned gradually to the control level by the time of 10th day. Microscopically primary lymph follicles with indistinct germinal center (GC) were partially disrupted and the parafollicular areas were consisted of the pyroninophilic cells in control group. In PC treated group, the parafollicular areas were markedly proliferated and developments of secondary lymph follicles with enlarged and prominent GC were more pronounced in the sequential injected groups compared to single injected groups. These results indicate that PC affected not only parafollicular area of the T-cell area, but also GC of the B-cell area. It suggests that PC may potentiate both cell mediated immunity and humoral immunity.

• BMB Reports
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• 제35권5호
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• pp.482-487
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• 2002

Early activation of human peripheral blood polymorphonuclear neutrophils is characterized by their morphological changes from spherical to polarized shapes. The endotoxins from enteric pathogens (S. dysenteriae type 1, V. cholerae Inaba 569B, S. typhimurium, and K. pneumoniae) were assessed by their ability to induce morphological polarization of the neutrophils as measures of early activation. Phagocytic activity, adhesion, chemokinetic locomotion, and nitroblue tetrazolium (NBT) dye-reduction ability measured the later activation of the cells. Neutrophils showed distinct morphological polarization in suspension over a wide range of concentrations of these endotoxins when were compared with those that were induced by the standard chemotactic factor, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). It was discovered that all of the endotoxins induced locomotor responses in neutrophils in suspension that were dose- and time-dependent. The optimum concentration for the endotoxins of S. dysenteriae, V. cholerae, and K. pneumoniae was 1 mg/ml in which 71, 69, and 66% of the neutrophils were polarized. However, the S. typhimurium dose was 2 mg/ml in which 50% of the cells responded. Neutrophils that were stimulated with endotoxins also showed increased random locomotion (p<0.005) through cellulose nitrate filters, but an enhanced adhesion of the cells to glass surfaces (p<0.03). These are important functions of these cells to reach and phagocytose damaged cells, as well as invading microorganisms. Interestingly, the endotoxins had a highly-significant inhibitory effect upon the proportions of neutrophils phagocytosing opsonized yeast (p<0.01) with a small number of yeast that were engulfed by the cells (p<0.02). Further, endotoxin-treated cells showed an enhanced ability to reduce NBT dye (p<0.03). Therefore, we concluded that endotoxins of enteric pathogens are neutrophil chemotactic factors.

• Ocean and Polar Research
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• 제32권4호
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• pp.369-377
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• 2010

To characterize ecotoxicological responses to a natural estrogen, $17{\beta}$-estradiol, we evaluated the life-history of the parental ($F_0$) and first generation ($F_1$) of the harpacticoid copepod, Tigriopus japonicus sensu lato. We evaluated the survival of nauplii and copepodites, the number of days until the emergence of copepodites and adult males, the sex ratio, brooding success, and the first brooding day of adult females. No significant differences in the survival rate were noted in response to treatments with different concentrations of $17{\beta}$-estradiol. However, $17{\beta}$-estradiol induced developmental delay and skewed the sex ratio toward males. Copepod development was delayed significantly in the 0.1 and $1\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment groups relative to the control group, with a more pronounced delay in the $F_1$ group. Body length and biomass were significantly smaller in the $17{\beta}$-estradiol treated groups than in the controls. The male emergence of T. japonicus s.l. was very high in the 10 and $30\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment group. Furthermore, exposure to $17{\beta}$-estradiol resulted in morphological deformities such as shrinking and swelling of the urosome, twisted setae of the caudal rami, setal loss of swimming legs, abnormal segmentation of antennules, and dwarfism.

• 동의생리병리학회지
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• 제26권5호
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• pp.738-744
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• 2012

Gastrodia elata Blume is used for a variety of purposes including treatment of inflammation in the Korean medicine. The present study investigated whether the G. elata extracts have the anti-inflammatory effect on lipopolysaccharide(LPS)-stimulated BV-2 microglia cells. G. elata extracts showed an anti-inflammatory effects in the morphological and nitric oxide(NO) analysis, especially in hexane extract. So we investigated the hexane extract from G. elata in the following experiments. Hexane extract significantly inhibited the secretion of NO with protein level of inducible nitric oxide synthase in LPS-stimulated BV2 microglia cells. Hexane extract also inhibited LPS-stimulated inflammatory responses involving the degradation of cytosolic inhibitory(I)-${\kappa}B{\alpha}$ and the translocation of nuclear factor(NF)-${\kappa}Bp65$ to nucleus in LPS-stimulated BV-2 microglia cells by morphological analysis. Western blot analyse confirmed that I-${\kappa}B{\alpha}$ and NF-${\kappa}Bp65$ showed a similar pattern as morphological analysis. Our results suggest that G. elata extracts, especially hexane extract, may act as a therapeutic agent for inflammatory disease in the central nervous system through a selective regulation of NO production and NF-${\kappa}B$ activation.

• The Korean Journal of Physiology and Pharmacology
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• 제6권3호
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• pp.155-160
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• 2002

It is not known whether gender differences play a role in susceptibility to ischemic acute renal failure. Thus, we examined if there were any differences in susceptibility between male and female mice to kidney ischemic injury, and if so, whether it is due to differences in mitogen activated protein kinases (MAPKs) or inflammatory responses to ischemia. Female mice were protected against kidney ischemia when compared with males. Thirty minutes of bilateral ischemia resulted in marked functional and morphological damages in males, but not in females. The ischemia-induced phosphorylation of c-jun N-terminal stress-activated protein kinases (JNKs) was higher in males than in females. Phosphorylation of extracellular signal-regulated kinases (ERKs) was lower in males than in females. Post- ischemia medullary infiltration of RAW 264.7 cell, a monocyte-macrophage cell, and intercellular adhesion molecule-1 (ICAM-1) were greater in males than in females. In conclusion, males were much more susceptible to ischemia than females. The enhanced propensity to ischemic injury in males was correlated with greater activation of JNKs, greater expression of ICAM-1, and greater trapping of leukocytes in the medulla.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.49-49
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• 2017

Sugar palm (Arenga pinnata (Wurmb.) Merr.) grows naturally under shading of tree canopy, therefore shading levels take a main role for an optimal growth of sugar palm seedlings. The study was conducted to examine the effect of shading levels on the seedlings growth of sugar palm for up to 11 months under four shading levels: S0 (100% of full sunlight or non-shading), S1 (32% shading level), S2 (56% shading level), and S3 (64% shading level). Sugar palm seedlings grown under the shade (32, 56, and 64%) showed better plant height, stem diameter, leaf size, petiole and rachis length, chlorophyll content, root fresh and dry weights, root volume, and total biomass than those grown without shading. Although there were no significant different responses among the shading treatments on plant height, biomass dry weight, leaf morphological characters, chlorophyll content, and SPAD value, the S2 treatment showed a significant effect on a better root characters. Therefore, it can be concluded that the S2 treatment, 56% shading level, is an optimal shading condition for sugar palm seedlings.

• ALGAE
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• 제38권4호
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• pp.203-215
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• 2023

Oomycete pathogens are one of the most serious threats to the rapidly growing global algae aquaculture industry but research into how they spread and how algae respond to infection is unresolved, let alone a proper classification of the pathogens. Even the taxonomy of the genera Pythium and Olpidiopsis, which contain the most economically damaging pathogens in red algal aquaculture, and are among the best studied, needs urgent clarification, as existing morphological classifications and molecular evidence are often inconsistent. Recent studies have reported a number of genes involved in defense responses against oomycete pathogens in red algae, including pattern-triggered immunity and effector-triggered immunity. Accumulating evidence also suggests that calcium-mediated reactive oxygen species signaling plays an important role in the response of red algae to oomycete pathogens. Current management strategies to control oomycete pathogens in aquaculture are based on the high resistance of red algae to abiotic stress, these have environmental consequences and are not fully effective. Here, we compile a revised list of oomycete pathogens known to infect marine red algae and outline the current taxonomic situation. We also review recent research on the molecular and cellular responses of red algae to oomycete infection that has only recently begun, and outline the methods currently used to control disease in the field.

• Journal of Microbiology and Biotechnology
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• 제9권4호
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• pp.422-428
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• 1999

Aromatic hydrocarbons can be utilized as carbon and energy sources by some microorganisms at lower concentrations. However, they can also act as stresses to these organisms at higher concentrations. Pseudomonas sp. DJ-12 is capable of degrading 0.5 mM concentration of benzoate and 4-chlorobenzoate (4CBA). In this study, the exposure of Pseudomonas sp. DJ-12 to the pollutant stresses of benzoate and 4CBA at various concentrations was comparatively studied for its cellular responses, including survival tolerance, degradability of the aromatics, and morphological changes. Pseudomonas sp. DJ-12 utilized 0.5 to 1.0mM benzoate and 4CBA as carbon and energy sources for growth. However, the organism could not degrade the aromatics at concentrations of 3 mM or higher, resulting in reduced cell viability due to the destruction of the cell envelopes. Pseudomonas sp. DJ-12 cells produced stress-shock proteins such as DnaK and GroEL when treated with benzoate and 4CBA at concentrations of 0.5mM, or higher as sublethal dosage; Yet, there were differing responses between the cells treated with either benzoate or 4CBA. 4CBA affected the degradability of the cells more critically than benzoate. The DnaK and GroEL stress-shock proteins were produced either by 1mM benzoate with 5 min treatment or by higher concentrations after 10min. The proteins were also induced by 0.5mM 4CBA, however, it needed at least 20min treatment or longer. These results indicate that the chlorination of benzoate increased the recalcitrance of the pollutant aromatics and changed the conditions to lower concentrations and longer treatment times for the production of stress-shock proteins. of stress-shock proteins produced by the aromatics at sublethal concentrations functioned interactively between the aromatics for survival tolerance to lethal concentrations.