• Applied Microscopy
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• v.27 no.2
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• pp.189-196
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• 1997

The ultrastrucures of Xenopus otic vesicle from normal embryo (st. 43) and induced otic vesicle from animal cap assay with Activin A were compared. Activin A was applied to the presumptive ectoderm at various concentrations for three days at $20^{\circ}C$. The results were almost identical to the reference studies, but it was found that the otic vesicle was induced at the concentration of 10 ng/ml in to)v rate. This otic vesicle may be secondarily induced by the neural tissue showed commonly at the concentration of 10 ng/ml. Otoliths were observed as three or four-axis crystaline bodies in the lumen of otic vesicle. In electron micrograph of the normal embryo, two kinds of microvilli were observed on the apical position of hair cells. One was small and common, the other was large-sized and sparsely distributed. In both cell of otic vesicle, mitochondria, golgi apparatus and multivesicular body were rich, so, they showed a lot of similarities in ultrastructure. However, the otolith was not found and microvilli were overexpressed in the otic vesicle induced by Activin A.

• Korean Journal of Veterinary Service
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• v.22 no.2
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• pp.135-149
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• 1999

This study was concerned with assessment of dietynitrosamine (DEN) induced liver cell carcinogenesis by measurement of changes preceding the development of neoplasms. The changes of hepatic morphology in rats(Sprague-Dawley) were detected by hematoxylin-eosin stain and immunohistochemistry(PCNA). The results were as follows ; 1. Minor behavioral change, brittleness of hair and decreased amount of water and diet intake. were observed in rats 7 weeks after DEN administration. 2. Variable size of liver tumor and hepatomegaly were observed in rats treated with DEN after 10 weeks. 3. Numerous vacuoles were showed on the midzonal and or peripheral areas of hepatic lobules. The large and polymorphological hepatocytes with eosinophilic cytoplasm or densely basophilic mitotic nucleoli were showed. 4. Several proliferative small round cells were shown on vacuolated and necrotic areas in peripheral hepatic lobules or portal areas. 5. PCNA-positive cells were showed on the vacuolated portal areas and peripheral areas of hepatic lobules. Maximal positivity was 23.6% in the areas of small round cells. In conclusion, this result confirmed that the DEN was one of the potent hepatocarcinogens. In histopathological analysis, the altered foci, hyperplastic nodules, neoplastic nodules, adenomas and carcinomas were observed in liver tumors induced by administration of DEN in rats.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.1-15
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• 2004

Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public firom agents that can cause mutation anuor cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

• Korean Journal of Veterinary Service
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• v.22 no.1
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• pp.61-70
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• 1999

This study is concerned with assessment of diethylnitrosamine(DEN) induced liver cell carcinogenesis by measurement of changes preceding the development of neoplasms. Therefore, it was undertaken to investigate the changes of liver-specific enzyme activities in rats (Sprague-Dawley) by ad libitum feeding of DEN. And also, as another objective index in urine, the level of urinary biopterin was measured by high performance liquid chromatography(HPLC) method. The results were as follows ; 1. Minor behavioral change, brittleness of hair and decreased amount of water and diet intake were observed in rats 7 weeks after DEN administration. 2. The body and liver weights were significantly(p<0.05) decreased in rats 11 weeks after DEN administration. 3. The ratio of liver weight to body weight was rather stable and not significantly decreased in the all treatment groups. 4. The liver specific enzyme activities(AST, ALT,$\gamma$-GTP) were significantly(p<0.05) increased in all treatment groups compared to control group. 5. Compared to normal level, urine biopterin level was significantly (p<0.05) increased in all treatment groups(p<0.05). In conclusion, this result confirmed that the DEN was one of the potent hepatocarcinogens. In experimental model of rats exposed to DEN, the results indicated that values of liver specific enzyme activities(AST, ALT, $\gamma$-GTP) and urine biopterin level could be useful complementary tumor indices.

• Journal of Genetic Medicine
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• v.3 no.1
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• pp.11-13
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• 1999

Recently it was reported that Insertion/Deletion polymorphism in the gene coding for Angiotensin-Converting Enzyme (ACE) is associated with human capacity for physical performance. This study was performed to genotyping of the ACE gene to determine the correlation between elite endurance performance and ACE I/D gene polymorphism. DNA sample was obtained from peripheral blood, hair roots and mouth epithelial cell in 739 general population and 200 elite athletic performance students. The ACE gene was amplified by polymerase chain reaction (PCR) using allele specific oligonucleotide primers. 155, 525 bp and 237 bp PCR products indicating the presence of insertion(I) and deletion(D) alleles, respectively, were clearly resolved after electrophoresis on a 2% agarose gel with ethidium bromide. Of the 200 elite athletic performance population subjects, 68(34%) showed ACE genotype 11,100(50%) genotype ID and 32(16%) genotype DD. Of the 739 general population subjects, 259(35.1%) showed ACE genotype 11,363(49.1%) genotype ID and 117(15.8%) genotype DD. Therefore ACE I/D gene polymorphism was not associated with human capacity for physical performance.(p>0.05)

• Archives of Craniofacial Surgery
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• v.19 no.4
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• pp.275-278
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• 2018

Trichoblastic carcinoma usually occurs as a malignant transformation of the trichoblastoma, but is very rare. A 25-year-old man was admitted with trichoblastoma in the nuchal area with frequent recurrences since birth. The preoperative neck magnetic resonance image revealed lobulated soft tissue lesions involving superficial fascia and infiltrating into both proximal trapezius muscles. In our department, wide excision and reconstruction with a free anterolateral thigh flap were performed. Histological examination revealed skin adnexal carcinoma, originating from the hair follicles, consistent with trichoblastic carcinoma. There was no palpable mass 5 years postoperatively, and there was no recurrence on follow-up positron emission tomography-computed tomography. Trichoblastic carcinomas are rare and difficult to diagnose, but histopathological findings include atypical basaloid keratinocytes with crowded, hyperchromatic nuclei, and increased mitotic activity. The presence of hypercellular stroma is a criterion for distinguishing trichoblastic carcinoma from basal cell carcinoma. A rare giant trichoblastic carcinoma was reported, which was the biggest one in the literature.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.1
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• pp.63-67
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• 2019

Interaction between epidermis and dermis plays an important role in wound healing and hair follicle formation. This study focused on investigating the potency of ethanol extract of Puerariae Radix (EPR) as cosmetic ingredient using human dermal fibroblasts (hDFn). Our results revealed that EPR suppressed collagenase activity dose-dependently. EPR inhibited activity of $5{\alpha}$-reductase I and II at the final concentration of $25{\mu}g/ml$ in hDFn cells. Also, EPR promoted the proliferation and the ERK activation of cells. ERK phosphorylation by EPR was blocked by specific inhibitor of ERK, PD98059. EPR-induced cell proliferation was blocked by PD98059. This means that EPR could promote the proliferation of hDFn cells via the activation ERK. Collectively, these results suggest that EPR may be used as a new cosmetic ingredient.

• Molecules and Cells
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• v.45 no.4
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• pp.169-176
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• 2022

A primary cilium, a hair-like protrusion of the plasma membrane, is a pivotal organelle for sensing external environmental signals and transducing intracellular signaling. An interesting linkage between cilia and obesity has been revealed by studies of the human genetic ciliopathies Bardet-Biedl syndrome and Alström syndrome, in which obesity is a principal manifestation. Mouse models of cell type-specific cilia dysgenesis have subsequently demonstrated that ciliary defects restricted to specific hypothalamic neurons are sufficient to induce obesity and hyperphagia. A potential mechanism underlying hypothalamic neuron cilia-related obesity is impaired ciliary localization of G protein-coupled receptors involved in the regulation of appetite and energy metabolism. A well-studied example of this is melanocortin 4 receptor (MC4R), mutations in which are the most common cause of human monogenic obesity. In the paraventricular hypothalamus neurons, a blockade of ciliary trafficking of MC4R as well as its downstream ciliary signaling leads to hyperphagia and weight gain. Another potential mechanism is reduced leptin signaling in hypothalamic neurons with defective cilia. Leptin receptors traffic to the periciliary area upon leptin stimulation. Moreover, defects in cilia formation hamper leptin signaling and actions in both developing and differentiated hypothalamic neurons. The list of obesity-linked ciliary proteins is expending and this supports a tight association between cilia and obesity. This article provides a brief review on the mechanism of how ciliary defects in hypothalamic neurons facilitate obesity.

• Anatomy and Cell Biology
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• v.56 no.3
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• pp.404-408
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• 2023

In arctic zone of West Siberia, native people's bodies were sometimes mummified inside the medieval graves. In 2013 to 2017, we conducted the excavations of medieval graves at Zeleny Yar cemetery in Yamalo-Nenets Autonomous Okrug. Among the burials, current report deals with the mummy grave #79. During the investigation, bronze plate and strips, woven or fur clothing, leather strap, beads, bronze bracelets, and iron knife etc. were collected. Anatomical and radiological research showed that the mummy was found intact with hair, skin, and skeletons, but the preservation status of soft tissue differed greatly depending on the area. The brain and eyes were well preserved, but the chest and abdominal organs almost disappeared. The arms were preserved to some extent, but only the bones remained in the legs. The West Siberian mummy could be a great resource for anthropologists to reveal the biological aspects of arctic indigenous people.

• Journal of Life Science
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• v.30 no.9
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• pp.819-825
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• 2020

All living organisms exhibit the characteristics of aging, such as skin wrinkle formation, muscle degeneration, cataracts, and hair graying as the number of aged cells increases over time. Senescence, which is known as a key cause of aging, is directly related to the aging of living organisms because cells are aged by external and internal factors and eventually cell proliferation is stopped. Senescence is caused by the gradual shortening of the telomere with cell division, and lifespan is determined by the length of the telomere. Recently, it has been found that the histone deacetylase, which can influence gene expression, is not only involved in yeast but also deeply involved in anti-aging mechanisms in both C. elegans and humans. It was also discovered that old cells play a decisive role in the aging phenomenon, and it has been reported that it is possible to promote the proliferation of young cells and delay aging by removing these senescent cells from the inside. Therefore, in order to develop potential anti-aging agents in the future, research should begin with an in-depth study of telomerase activators, sirtuin activators, and senolytics.