• Proceedings of the KAIS Fall Conference
• /
• 2012.05a
• /
• pp.182-186
• /
• 2012

human tyrosinase (hTyr) catalyzes first and the rate limiting step in the synthesis of polymerized pigment, melanin which determines skin, hair and eye colors. Mutation of hTyr often brings about decrease of melanin production and further albinism. Meanwhile, a number of cosmetic companies providing skincare products for woman in Asia-Pacific region have tried to develop inhibitors to bright skin color for several decades. In this study, we built a 3D structure by comparative modeling technique based on the crystal structure of tyrosinase from bacillus megaterium as a template to serve structural information of hTyr. According to our model and sequence analysis of type 3 copper protein family proteins, two copper atoms of active site located deep inside are coordinated with six strictly conserved histidine residues coming from four-helix-bundle. Cavity which accommodates substrates was like funnel shape of which entrance was wide and expose to solvent. In addition, protein-substrate and protein-inhibitor complex were modeled with the guide of van der waals surface generated by in house software. Our model suggested that only phenol group or its analogs can fill the binding site near nuclear copper center because inside of binding site has narrow shape relatively. In conclusion, the results of this study may provide helpful information for designing and screening new anti-melanogensis agents.

• Journal of Veterinary Clinics
• /
• v.34 no.6
• /
• pp.445-448
• /
• 2017

A 1.5-year-old neutered male domestic short hair cat was presented with multiple nodular mass, and suspected mast cell tumor on the surface of the right ear, accompanied by submandibular lymph node involvement. Histopathological Examinations and KIT (CD117) immunohistochemical staining was performed after the surgical resection of the entire right ear pinna. This patient was diagnosed with an anaplastic mast cell tumor with a diffuse positive cytoplasmic expression of KIT. Imatinib mesylate was prescribed after surgical resection; the patient presented without recurrence or metastasis for 2 years. Mild leukopenia was observed as the only side effect of imatinib mesylate during medication.

• Archives of Reconstructive Microsurgery
• /
• v.25 no.1
• /
• pp.19-24
• /
• 2016

Urethral reconstruction is a problematic issue, thus its management can be challenging. Different methods using various materials were introduced for urethral reconstruction. The authors have made some changes in the groin flap surgery, affording more successful urethral reconstruction for defects of long urethra and penile soft tissue. A 45-year-old male requested both functional and cosmetic reconstruction of his defected penis, caused by an iatrogenic urethral injury and chronic infection following removal of paraffin self-injected on the penile shaft. The defect affected the full length of the penile urethra, corpus spongiosum, and prepuce. A groin flap was designed, measuring $28{\times}10cm$. The most distal flap was utilized for the construction of the luminal surface of the neourethra; relaxed length measuring 8 cm, and the lumen wide enough. Competent external meatus and neourethra was confirmed by retrograde cystogram and the patient voided with sufficient urine caliber up to 2 years follow-up. This operative technique has advantages. Donor sites have non-hair bearing skin for the neourethra and minimal or almost notrecognizable donor site morbidity. After surgery, the patient was relieved from voiding difficulties combined with psychological stress. The author would like to introduce a unique approach for the urethral and ventral phalloplasty using the groin flap.

• Biomolecules & Therapeutics
• /
• v.26 no.2
• /
• pp.182-190
• /
• 2018

The objective of this work is to evaluate the effect of polyamidoamine (PAMAM) dendrimers on electroosmotic flow (EOF) through skin. The effect of size and concentration of dendrimer was studied, using generation 1, 4 and 7 dendrimer (G1, G4 and G7, respectively). As a marker molecule for the direction and magnitude of EOF, a neutral molecule, acetoaminophen (AAP) was used. The visualization of dendrimer permeation into the current conducting pore (CCP) of skin was made using G4-fluorescein isothiocyanate (FITC) conjugate and confocal microscopy. Without dendrimer, anodal flux of AAP was much higher than cathodal or passive flux. When G1 dendrimer was added, anodal flux decreased, presumably due to the decrease in EOF by the association of G1 dendrimer with net negative charge in CCP. As the generation increased, larger decrease in anodal flux was observed, and the direction of EOF was reversed. Small amount of methanol used for the preparation of dendrimer solution also contributed to the decrease in anodal flux of AAP. Cross-sectional view perpendicular to the skin surface by confocal laser scanning microscope (CLSM) study showed that G4 dendrimer-FITC conjugate (G4-FITC) can penetrate into the viable epidermis and dermis under anodal current. The permeation route seemed to be localized on hair follicle region. These results suggest that PAMAM dendrimers can permeate into CCP and change the magnitude and direction of EOF. Overall, we obtained a better understanding on the mechanistic insights into the electroosmosis phenomena and its role on flux during iontophoresis.

• Applied Microscopy
• /
• v.1 no.1
• /
• pp.11-17
• /
• 1969

Conidio spores of Aspergillus niger (strain No. NRRL 330) cultured on potato dextrose agar media were studied by electron microscopy, using the thin sectioning techniques. Conidio spores to be sectioned were fixed by triple methods with $K_2Cr_2O_7$, Glutaraldehyde and $OsO_4$. After dehydrated with alcohol, the specimens were embedded in metacrylate and epon resin media, and thinly sectioned by Porter-Blum MT-2. After sectioned these specimens were negative-stained with uranyl acetate and observed. by Hitachi HS-6 electron microscope. The results of this experiment were summarized as follows. 1. The structures of spore ,wall system seem to be formed 4 layers; exosporium, basal layer, spore coat and unit cell membrane. The protuberance of spore surface that was looked like hair appears to be protrusived from the basal layer. 2. The 3 layers of unit cell membrane was constituted outer layer membrane, inner layer membrane and inter-mediate light layer. 3. The structures of intra cytoplasmic membrane appear as spiral form which was consisted of 3 layers membrane system; outer membrane, inner membrane, and intermediate layer, which has pits. 4. The cement substance of spore coat and cortex may be changed quantitatively by physiological state in cell. 5. In some cases, we observed that the ribosome was transformed into poly ribosome group, and the storage materials and the protein crystals were changed variously. It. has been suggested that the morphological change of some cytoplasmic materials may be caused by some specialized function of the physiological stage.

• Journal of Veterinary Clinics
• /
• v.25 no.1
• /
• pp.19-22
• /
• 2008

Adenomyosis is a nonneoplastic proliforation of uterine glands characterized by multicentric infiltration of endometrial tissues into the myometrium. A female domestic short hair cat with unknown age was referred to local animal hospital in Busan for ovariohysterectomy to prevent the unwanted offspring. At the time of surgery, the uterus was enlarged with multiple nodular protrusion on the serosa. On the cut surface of uterus, elevation of the endometrium and hypertrophied myometrium were observed. Microscopically, the uterus was characterized by severe proliforation of endometrial glands into the lumen and within the myometrium. The intra-myometrial endometrium is circumferentially surrounded by bundles of hypertrophic smooth muscle cells. These endometrial glands had tall columnar epithelium lacking nuclear atypia and mitoses. In our best knowledge, this is the first report of feline adenomyosis in Korea.

• Korean Journal of Plant Taxonomy
• /
• v.40 no.4
• /
• pp.251-254
• /
• 2010

We describe a new taxon of Goodyera (Orchidaceae), G. ${\times}$ tamnaensis N.S. Lee, K.S. Lee, S.H. Yeau & C.S. Lee, sp. nov., from Jeju Island. This taxon is presumed to be a hybrid between G. schlechtendaliana and G. velutina based on several morphological characteristics, i.e., leaf venation, a patterned leaf surface and raised leaf epidermal cells, the color of the flower and the bract, the lateral sepal shape, and the hair length. The morphological characteristics and illustrations of the species based on the holotype are provided together with photographs of the habitat.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.28 no.3
• /
• pp.299-304
• /
• 1983

It has been ascertained by a few researchers that soil conditions under which the rice plants were cultivated have some effects upon the root formation of the rice plants. But, much is not known about the root formation of the rice plants cultivated in the saline paddy fields. The goal of the present investigation is to study morphological effects of the soil salinity on the development of the rice root system. The following results were obtained: 1. Under the conditions of higher soil salinity, root systems developed well at surface soil, however, root systems developed well and distributed evenly through surface and sub-soil at the saline fields where soil salinity was lower. 2. The rice plants cultivated in the higher soil salinity form less crown roots than the rice plants which cultivated at the lower soil salinity. 3. As for the formation of the stunted roots, it was found out that relatively rice plant cultivated in higher soil salinity forms more stunted roots than the rice plants cultivated in lower soil salinity. 4. The crown root cultivated in the higher soil salinity forms more lateral roots per unit langth than the root cultivated in lower soil salinity. 5. As for the root hair formation, the crown root cultivated in higher soil salinity bears less haired epidermis and shorter root hairs than the root cultivated in lower soil salinity.

• Korean Journal of Plant Taxonomy
• /
• v.32 no.4
• /
• pp.481-489
• /
• 2002

Unrecorded fern species of Korean flora, Thelypteris interrupta (Willd.) K. Iwats. (Thelypteridaceae) and Dryopteris subexaltata (H. Christ) C. Chr. (Dryopteridaceae), were collected from Jeju island off the south coast of Korean peninsula and reported here. T. interrupta is most similar to T. acuminata (Houtt.) C. V. Morton in morphology, however, the two species are readily distinguishable by the plant color including rhizome, stipe base and spore, and the presence of glandular hair as well as the distribution pattern of sorus on lower leaf surface. D. subexaltata is also well distinguishable from its relatives, D. sparsa (D. Don) Kuntze, D. sabaei (Franch. & Sav.) C. Chr., and D. yakusilvicola Sa. Kurata by the presence of proliferation, shape of pinnae, distribution pattern of sori on lower leaf surface, and shape of indusium.

• Korean Journal of Veterinary Pathology
• /
• v.7 no.1
• /
• pp.63-65
• /
• 2003

A 10-year-old Korean native female Jin-do dog revealed two growing subcutaneous masses measuring 7.0 ${\times}$ 7.0 ${\times}$ 2.5 cm and 5.0 ${\times}$ 4.0 ${\times}$ 2.0 cm in the left shoulder and lower part of chest, respectively. Grossly tumor masses were well-circumscribed and exhibited ulcerated surface and purulent exudate on the cut surface. Histologically tumor masses were characterized by cystic structures some of which were fused together. Although the cells of cyst wall differentiated to those similar to infundibulum, isthmus, inferior segment of hair follicles, respectively, the most cyst wall consisted of cells similar to infundibulum The luminal content of cysts depended on the cells of cysts; infundibulum-like cyst contained lamellar keratin, isthmus-like cyst was amorphous keratin, and inferior segment-like cyst had shadow cells. From these results, these tumor masses were diagnosed as multiple trichoepithelioma. To our knowledge, this is the first report of canine multiple trichoepthelioma in a dog in Korea.