• Microbiology and Biotechnology Letters
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• v.24 no.5
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• pp.553-559
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• 1996

We have designed nucleotide sequences of hEGF structural gene to eliminate the N-terminal methionine residue incorporated during the translation initiation step, and constructed recombinant human epidermal growth factor (rhEGF) secretion plasmids pYHB101, and pYHB2 in which pelB signal sequence-hEGF gene was expressed under the control of the T7, and tac promoter, respectively. We also constructed pYHB1 vector which contains rhEGF gene controlled by T7 promoter. The transformant with pYHB101 showed relatively slow growth pattern compared to the transformant with pYHB1. However, we observed that the transformant with pYHB101 secreted rhEGF of 13 mg/l significantly after 5 hr induction with 1 mM IPTG and that the T7 promoter was more effective than tac promoter when connected to pelB signal sequence. The amount of rhEGF was 14 mg/l under the sub-optimized condition.

• Applied Microscopy
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• v.44 no.4
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• pp.111-116
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• 2014

This study investigates the developmental pattern of adhesive discs (ADs) to highlight the ontogeny and structural changes that occur during the growth of Boston ivy. Initiation to postmortem features of ADs were examined through light and scanning electron microscopy. The study also reveals a new finding of the dislocation of peripheral tissues of adaxial origin. Four phases of attachment are suggested with regards to its climbing behavior: 1) pre-attachment, 2) upon attachment, 3) after attachment, and 4) final attachment. During initiation, several ADs originate from tendril primordia without epidermal differentiation. However, different growth rates in the epidermis results in completely different ADs. ADs were discerned by size, shape, and color during expansion, but cells in the adaxial surface remained alive longer than the other side. Upon contact, the ADs demonstrate simultaneous growth and deterioration, but once attachment is established the latter process subdues to final stages. Epidermal transformation, adhesive secretion, cellular disruption, and mechanical stress were essential for the self-clinging nature of Boston ivy. The post-attachment sequence is also believed to be critical in achieving maximum mechanical strength to provide extensive support. The developmental process of ADs is prompted by tactile stimulation but in a highly organized and systematic manner.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.245-249
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• 2008

Epidermal growth factor is a single-chain polypeptide consisting of 53 amino acids and has a potent mitogenic activity that stimulates proliferation of various normal and neoplastic cells through the interaction with its specific receptor(epidermal growth factor receptor, EGFR). Pleomorphic adenoma is the most common salivary benign tumor and histologically, it contains the epithelial cell, the myo-epithelial cell and mesenchymal ingredient, which is various aspect. Adenoid cystic carcinoma is an infiltrative malignant salivary gland tumor with three different histological patterns: cribriform, tubular or solid. The tumor cell structure composed of modified myoepithelial cell, and basaloid cell. In this study, we used an immunohistochemical technique to investigate the expression of EGF in 6 specimens of adenoid cystic carcinoma and 10 specimens of pleomorphic adenoma taken from patients treated at Dept. of Oral and Maxillofacial Surgery, Dankook University. The results were as follows. 1. In pleomorphic adenoma, ductal structure and scattered spindle cells in hyalinized stroma, disclosing myxoid stroma and hyalin, cartilage formation were observed. Immunohistologically, weak EGF expression in ductal structure and negative in stromal area were observed. 2. Cribriform type of adenoid cystic carcinoma showed numerous pseudocyst surrounded by dark small neoplastic cells in the back-ground of fibrous connective tissue and moderate EGF expression of dark cells adjacent to pseudo lumen in cribriform pattern, while weak expression in other most cells. 3. Tubular type of adenoid cystic carcinoma showed numerous ductal pattern surrounded by two layered neoplastic cells in the back-ground of fibrous connective tissue and strong EGF expression in luminal cells of ductal structure, while weak expression in outer cells. From the results obtained, we suggest that EGF is mainly biosynthesized in cells forming duct like structures of tubulo-ductal type or cribriform adenoid cystic carcinoma and it may play a role, as a cell mitogen in adenoid cystic carcinoma growth.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.225-235
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• 1988

This study was carried out to compare distribution and isozyme pattern of nonspecific esterase, acid phosphatase and alkaline phosphatase on developing sparganum and adult of Spinometra erinacei by using enzyme-histochemical method and electrophoresis The sparganum and adult were recovered from rats and cat that were infected by sparganum. The results obtained were as follows: Nonspecific esterase had a strong activity in the parenchymal musculature of sparganum and adult, but no detectable level in ihe tegument. A total of 7 and 8 nonspecific esterase bands were detectable in sparganum and adult, respectively. Of these bands, band 3 and 4 were major bands in sparganum and adult. Acid phosphatase had a strong activity in the tegument and the epidermal musculature of sparganum, but no detectable level in the parenchymal musculature. A total of 3 bands were detectable in sparganum and adult. Of these bands, band 3 was major band in sparganum and adult. Alkaline phosphatase had a strong activity in the tegument and the epidennal musculature of sparganum and of adult, but no detectable level in the parenchymal musculature. A total of 2 and 4 bands were detectable in sparganum and adult. Of these bands, band 2 was major band in sparganum and adult. Based on the present results isozyme band patterns showed qualitative and quantitative changes in each tissues of sparganum and of adult during the development.

• Korean Journal of Veterinary Service
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• v.41 no.1
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• pp.57-61
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• 2018

Canine peripheral nerve sheath tumors (PNSTs) are spindle cell tumors that arise from Schwann cells, perineural cells, fibroblasts or all of them. Based on the morphology and biologic behavior, PNSTs are divided into benign PNST (BPNST) and malignant PNST (MPNST) forms. The aim of this study is to diagnose the two cases of neoplastic tissue samples with features of PNSTs by the histopathology and immunohistochemistry. The study was performed using two specimens from small animal clinic. The first case, A was a mass, 3~4 cm in diameter, extruded from vaginal mucosa of 10-year-old spayed female mixed-breed dog. And the second case, B was a subcutaneous mass, 1.5 cm in diameter, which is originated from right hind leg of 9-year-old castrated male mixed-breed dog. Two cases were stained with hematoxylin and eosin (H&E) for histopathological examination. And also immunohistochemistry (IHC) was performed by the avidin-biotin peroxidase complex (ABC) method with antibodies specific for the following proteins: S-100 protein, smooth muscle actin (SMA) and epidermal growth factor receptor (EGFR). In results, Antoni B schwannoma pattern characterized by pleomorphic, round and fusiform polygonal cells was seen in A. In B, Antoni A pattern, densely packed spindle cells arranged in interlacing bundles was seen in addition to Antoni B pattern. In IHC, cytoplasms of neoplastic cells were diffusely labeled for S-100 expression in A and B. For SMA, both A and B show negative expression. And for EGFR, A shows negative expression but B shows partially positive expression in areas of Antoni B schwannoma pattern. The histopathologic features of two cases coupled with the S-100 immunoreactivity led to a diagnosis of PNST. For SMA, both A and B show negative expression. The diagnosis of A will be a BPNST with the negative result and B will be a MPNST with the positive result for EGFR.

• Journal of Photoscience
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• v.9 no.2
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• pp.217-220
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• 2002

Ultraviolet B (UVB) radiation may activate or deteriorate cultured human epidermal melanocytes, depending on the doses and culture conditions. In this study, we examined whether apoptosis of melanocytes can be induced by physiologic doses of UVB irradiation. PI staining for DNA condensation and flow cytometric analyses demonstrated the apoptotic cell death of melanocytes after UVB irradiation. The level of p53 and Bax revealed a dose-dependent increase with increasing dose of UVB, but the level of Bcl-2 remained unchanged. Confocal microscopic examination showed that Bax moved trom a diffuse to a punctate distribution after UVB irradiation. However, there were no changes in the pattern of Bcl-2. We next examined the downstream targets of apoptosis. Our results showed that a precursor form of caspase-3 disappeared with increasing doses of UVB. We also observed cleavage of poly(ADP-ribose) polymerase (PARP) after UVB irradiation. In addition, UVB irradiation resulted in a remarkable activation of c-Jun N-terminal kinase (JNK). These results indicate that UVB may induce apoptosis via JNK activation in human melanocytes.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1279-1287
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• 2006

The purpose of this paper is to present a new algorithm for extracting the consensus pattern, or motif from sequence belonging to the same family. Two methods are considered for feature interval partitioning based on equal probability and equal width interval partitioning. C2H2 zinc finger protein and epidermal growth factor protein sequences are used to demonstrate the effectiveness of the proposed algorithm for motif extraction. For two protein families, the equal width interval partitioning method performs better than the equal probability interval partitioning method.

• Journal of Aquaculture
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• v.16 no.1
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• pp.37-43
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• 2003

The present study reports morphology and developmental pattern off siliquosa cultured in a laboratory condition. The zygote was spherical with a diameter of 85 ${\mu}{\textrm}{m}$. During development the polarized zygote divided horizontally and the lower daughter cell divided horizontally into 2 cells. The upper cell was divided repeatedly in horizontal and vertical directions to form a cylinder-like structure, which subsequently developed into secondary and tertiary dichotomous branches. Optimum temperature for zygote release and fertilization was 25C. Injury inflicted by slicing was cured by epidermal differentiation, and adventitious branches; the branches emerging from the pith cells, however, developed no rhizoid. Adventitious branch formation rate was over 88% in all plates supplemented with 0.5 mg/L IAA and peaked at 98% under 0.5 mg/L IAA plus 0.5-5.0 mg/L NAA treatment. NAA stimulated the differentiation of adventitious branches at a wide range of concentrations, while IAA, 2,4-D and kinetin exhibited dose-dependent stimulation.

• Animal cells and systems
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• v.6 no.4
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• pp.301-304
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• 2002

In our previous study, we have shown that Fgf-8 is expressed in the basal layer of the apical epithelial cap (AEC) and in the underlying thin layer of mesenchymal tissue of the regenerating limbs of Mexican axolotl, Amby-stoma mexicanum. Our present RT-PCR data also demonstrate that Fgf-8 transcript is localized both in the mesenchymal and epidermal tissues. To understand the effect of retinoic acid (RA) on the expression of Fgf-8 in the regenerating axolotl limbs, RA was injected intraperitoneally at the dediffer-entiation stage of limb regeneration. The RA treatment caused 8 change in the Fgf-8 expression profile of the regenerating limbs. In RA-treated limbs, duration of Fgf-8 expression was prolonged and a high level of expression was maintained during dedifferentiation and blastema formation stages. These results suggest that Fgf-8 is an important molecule in the process of pattern duplication of regenerating salamander limbs evoked by RA treatment.

• Korean Journal of Plant Taxonomy
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• v.37 no.3
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• pp.239-254
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• 2007

A comparative micromorphological study was examined on the leaves of the genus Glechoma and related genera (Nepetinae, Lamiaceae) by scanning electron microscopy (SEM) in order to evaluate their significance in the taxonomy. The leaves of taxa Marmoritis, Nepeta sect. Glechomanthe, G. hederacea var. longituba (Korea) are revealed amphistomatic type, while the remnants of taxa had hypostomatic type. The size range of the guard cells is $12.50-28.75{\times}9.17-21.25{\mu}m$: the smallest one was found in M. pharicus ($12.50-15.83{\times}9.17-11.25{\mu}m$), while the largest one was measured to G. hederacea var. longituba (Korea: $28.75-28.88{\times}21.25-21.38{\mu}m$). The stomatal type of genera Agastache, Dracocephalum was mostly diacytic, however for the rest rarely together with anisocytic and anomocytic, except G. hederaca var. longituba (Korea), Meehania urticifolia by having combined with diacytic and anomocytic. The shapes of epidermal cells are differ from in abaxial and adaxial side, and dived with two types (e.g., platelet, stripe pattern). Five types (three glandular, two non-glandular hairs) of trichomes are distributed in leaves. Among trichomes, long and stalk capitates glandular trichome, subsessile glands are different from studied taxa so that leaf micromorphological characters are significance features in the taxonomy.