• Journal of Mechanical Science and Technology
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• v.14 no.3
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• pp.338-349
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• 2000

Neck muscle forces and spinal loads at the C4/5 level were estimated that result from isometric voluntary ramp efforts gradually developing to maximums in flexion, extension, left lateral bending and right lateral bending. Electromyographic (EMG) activities, a three-dimensional anatomic data of the neck and a hybrid model, EMG-assisted optimization (EMGAO) model, were used. The model computed the cervical loads at 25%,50%,75%, and 100% of peak moments. The highest model-predicted C4/5 joint compressive forces occurred during flexion; $361\;({\pm}164)\;N,\;811\;({\pm}288)\;N,\;1207\;({\pm}491)\;N\;and\;1674\;({\pm}319)\;N$ in 25%, 50%, 75% and 100% of peak moment respectively. Variations in load distribution among the agonistic muscles and co-contractions of antagonistic muscles were estimated during ramp efforts. Results suggest that higher C4/5 joint loads than previously reported are possible during isometric, voluntary muscle contractions. These higher physiological loads at C4/5 level must be considered possible during orthopedic reconstruction at this level.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.98-103
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• 1995

During the screening of antifungal antibiotics from microbial metabolites, we selected Pseudomonas aeruginosa KGM-100 showing powerful antagonistic activity against various phytopathogenic fungi. Antibiotics KGM-100A and KGM-100B were purified from the culture broth of Pseudomonas aeruginosa KGM-100 by diaion HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, preparative TLC and recrystallization. KGM-100A which was recrystallized in MeOH showed antimicrobial activities against a broad spectrum of fungi and bacteria. Physico-chemical properties of KGM-100A were determined and identified to be phenazine-l-carboxylic acid by UV, IR, $^{1}$H-NMR, $^{13}$C-NMR, mass spectrum, and elemental analyses.

• Natural Product Sciences
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• v.20 no.4
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• pp.281-284
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• 2014

In this study, twenty-one oleanane-type triterpenoid saponins were isolated from a methanol extract of the roots of Pulsatilla koreana. Antagonistic activities were measured in these compounds by the aequorin based cellular functional assay system for the corticotropin releasing factor receptor (CRF1). Of them, compounds 7 - 10 showed the highest degree of CRF1 inhibition further at the concentration of $10{\mu}M$. Moreover, by the analysis based on the structure-activity relationship of isolated saponins, a sugar chain at C-3 and a carboxyl group at C-28, as well as a methyl group at C-23 seems to be key functional elements. To our knowledge, this is the first report on CRF1 inhibition of saponins from P. koreana.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.103-108
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• 1995

Antibiotic and physico-chemical properties of an active compound from actinomycetes isolate G-37, of which the culture filtrate had an inhibitory effect against tobacco mosaic virus(W) infection, were examined. The active compound, which was purified by ethylacetate extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography, showed strong antibacterial activities especially against Gram-positive bacteria including Bacillus subtillis, Sarcina lutea and Staphylococcus aureus. From the IH-NMR, FAB/RfS, UV spectral data, and physicochemical properties, the active compound of G-37 appears to belong to a peptide antibiotic group. Among the known peptide antibiotics in the antibiotic group, No. 280, A-30912, and Taitomycin showed molecular weights and ultra violet spectrum similar to those of the active compound from G-37, but was not identical to the compound, which suggests that it may be a new peptide antibiotics.

• Journal of Plant Biology
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• v.11 no.1
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• pp.22-26
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• 1968

Hypocotyl segments of shade-grown soybean sprouts(var. Kumdo) were floated in solutions of various substances at physiological levels and grown for either 24 hours at 28$^{\circ}C$ or 72 hours at $25^{\circ}C$. Increased length of the segments beyond 20mm (the original length) was obtained as a measure of the present studies. At the room temperature, Ca and DNP strongly inhibited elongation of the hypocotyl segments, whereas K, IAA, GA and EDTA in general promoted it. There were, however, no such differences in the effects at relatiely low temperature. This indicated that the elongation process not only involves stretching of wall materials, but also does synthesis of the materials. Ca was found to be antagonistic to the promotive action of GA in the elongation, and the IAA action involves metabolic energy. EDTA seemed to act as a widely known chelator removing Ca already existed in the hypocotyl tissue, thus shwoed a promotion in the elongation.

• Korean Journal of Pharmacognosy
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• v.31 no.4
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• pp.407-411
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• 2000

Antibacterial activities of magnolol (MGL) and honokiol (HKL) in combination with four representative antibiotics-amoxicillin (AMPC), oxytetracyclin (OTC), gentamicin (GM) and chloramphenicol (CAP)-were evaluated against four bacterial strains. When tested by disk-plate method, five out of eight combinations such as HKL-AMPC, HKL-CAP, MGL- AMPC, MGL-OTC, and MGL-CAP showed additive to synergistic interaction against gram- negative bacterium Salmonella typhimureum. Of these, MGL-AMPC combination turned out to be antagonistic against Sarcina lutea and Bacillus thurungiensis. Against these two grain-positive bacteria, only HKL-GM combination showed additivity to synergism. All the other combinations showed no interactions. Despite these results, however, no synergism was observed in checkerboard titration assay.

• Mycobiology
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• v.49 no.5
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.398-402
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• 2013

This study was to investigate beneficial effects of microbial mixture on red pepper which was capable of promoting plant growth by solubilizing insoluble phosphate as well as protecting plants from pathogenic attack. Saccharomyces sp. L13 was isolated for phosphate solubilizing activity on aluminium phosphate, tricalcium phosphate, calcium hydrophosphate, and magnesium hydrophosphate. On the other hand, Bacillus sp. L32 was isolated for antagonistic activity against Phytophthora capsisi and Colletotrichum gloeosporioides, causing Phytophthora blight and Anthracnose disease in pepper, respectively. The strain L32 exhibited antagonistic activities both under dual culture assays and detached leaves assays. The each strain under the condition of mixed cultivation exhibited the same growth rates as one under pure cultivation. In greenhouse study, the mixed culture showed the both effect of plant growth promotion and reduction of disease symptom development against P. capsisi and C. gloeosporioides providing a potential as effective microbial agent for plant husbandry.

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.135-141
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• 2002

This study was carried out to isolate antagonistic bacterium against Sclerotium cepivorum causing Allium fistulosum white rot. Total of 146 strains were isolated from A. fistulosum roots. The isolates were screened for antagonism to S. cepivorum and the isolated strain No. AL-1 was selected among these bacteria. It was identified as Serratia plymuthica based on morphological and physiological characteristics according to the Bergey's mannual of systematic bacteriology and 16S rDNA sequences methods. Serratia plymuthica AL-1 showed broad spectrum of antifungal activities against plant pathogenic fungi Alternaria altrata, Colletotrichum gleosporioids, Phoma sp., Rhizoctonia solani, Sclerotinia sclerotiorum, Stemphylium solani, Fusarium oxysporium niveum but not inhibited Didymella bryoniae. When S. plymuthica AL-1 cultivated in the TSB medium containing 1％ colloidal chitin, the high molecular fraction (>10 kDa) have chitinase activity (3.2 units/ml) and the low molecular fraction (<10 kDa) have not chitinase activity. Oppositely, after heat treatment (80℃ for 30 min) of the cultivation supernatant, the high molecular fractions have not antifungal activity but the low molecular fractions have antifungal activity.

• Journal of Veterinary Clinics
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• v.12 no.1
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• pp.799-818
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• 1995

This study was performed to examine the general anesthetic efficacy of tiletamine-zolazepam, a mixture of phencyclidine-derived tiletamine and benzodiazepine-related zolazepam. The antagonistic activities of doxapram and yohimbine to the anesthetic effects of tiletamine-zolazepam were also studied. Thirty healthy mongrel dogs were divided into three groups (each of 10) twenty minutes after being anesthetized with tiletamine-zolazepam : T-Z-S group(tiletamine-zolazepam-saline), T-Z-D group (tiletamine -zolazepam-doxapram), T-Z-Y group (tiletamine-zolaz.pam-yohim bine). Various parameters wert evaluated in terms of the onset and recovery time of analgesia, respiration rates, hear rates, body temperature, electrocardiogram, blood chemistry, and lymphocyte blastogenesis. The results obtained through these experiment could be summarized as follows: 1. he anesthetic efficacy of tiletamine-zolazepam was considered desirable, with the onset time of anesthesia being as short as 0.23-0.24 minutes. 2. Both of the antagonistic effects of yohimbine and doxapram on the anesthesia induced by liletamine-zolazepan were evaluated statistically significant(p<0.05) as the recovery time was shortened from 39.3$\pm$4.9 min(T-Z-S group) to 25.3$\pm$2.9 nin(T-Z-Y group) and 29.9$\pm$8.8min(T-Z-D group), respectively. 3. Respiration rates were not changed by the treatments of both doxapram and yohimbine, with the only transient increase in the T-Z-D group. The changes in the respiration rate were not observed during the whole time course of the experiment. 4. Yohimbine(T-Z-Y group) increased the heart rate significantly from 30 minutes after the adminstration compared to the T-Z-S group and T-Z-D group (p<0.05). 5. The decreases in th, body temporature were observed from 30 minutes in the T-Z-S group(p<0.05) and 40 minutes in th, T-Z-D group(p<0.05), after the adminstration. On the other hand, there was no hypothermia in the T-Z-Y group. 6. In the all experimental groups of the T-Z-S, T-Z-D and T-Z-Y, there were no specific findings on the electrocardiograph incept slight shift to the tachycardia in all cases. 1. We could not find any differences in the blood chemistry between all experimental groups (T-Z-S, T-Z-D and T-Z-Y). 8. the inhibition of the lymphocyte blastogenesis shown in the T-Z-S with 3 hours decreasing and thereafter restoring to the normal values up to the point 5 hours were not occurred in the T-Z-D and T-Z-Y groups. With the above results, we could conclude that both doxapram and yohimbine can be clinically used as recovery agents towards anesthesia by tiletamine- zolazepam fi:on the efficacy point of view, but yohimbine is more recommendable in this case if considering the recovery time and lymphocyte blastogenesis.