• The Korean Journal of Physiology and Pharmacology
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• v.1 no.5
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• pp.495-504
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• 1997

Water transport is mediated by two distinct pathways, diffusional and channel-mediated water transport. The first molecular water channel was identified from human erythrocytes in 1992. Genetically-related proteins from other mammalian tissues have subsequently been identified to transport water, and the group is referred to as th "Aquaporins". Aquaporin-4 (AQP4) is most abundant in the brain, which may be involved in CSF reabsorption and osmoregulation. However, ontogeny and regulatory mechanisms of AQP4 channels have not been reported. Northern blot analysis showed that AQP4 mRNA began to be expressed in the brain just before birth and that its expression gradually increased by PN7 and then decreased at adult level. AQP4 was expressed predominantly in the ependymal cells of ventricles in newborn rats. And then its expression decreased in ependymal cells and increased gradually in other regions including supraoptic and paraventricular nuclei. AQP4 is also expressed in the subfornical organ, in which the expression level is not changed after birth. Cryogenic brain injury did not affect expression of AQP4 mRNA, while ischemic brain injury decreased it. Osmotic water permeability of AQP4 channel expressed in Xenopus oocytes was inhibited by the pretreatment of BAPTA/AM and calmidazolium, a $Ca^{2+}/Calmodulin$ kinase inhibitor, in a dose-dependent manner. These results indicate that the expression and the function of AQP4 channel are regulated by developmental processes and various pathophysiological conditions. These results will contribute to the understanding of fluid balance in the central nervous system and the osmoregulatory mechanisms of the body.

• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.311-316
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• 2008

A 7-year-old female Shih Tzu dog with lots of masses in the whole mammary gland was presented to the surgery department of the Veterinary Teaching Hospital in the Cheju National University. After surgical excision, all mammary samples were referred to Pathology Department of Veterinary Medicine. Grossly, masses were measuring up to $6.5{\times}4{\times}1cm$ and on cut surface of masses in right 1st, 3rd, 4th, 5th and left 1st, 3rd, 4th, 5th mammary masses were well delineated and firm, sulphur yellow, solid round to oval shape. Microscopically, most neoplastic sweat glands were severely proliferated in dermis and subcutis. Most tubules were lined by round to oval shaped epithelium with eosinophilic cytoplasm, hyperchromatic nuclei with high mitotic figures and severe central necrosis. The neoplastic epithelium also had PAS-positive diastase-resistant cytoplasmic granules, but negative with Perls iron stain. The left 2nd mass was well delineated, and had several dark brown areas and yellowish white glittered areas. Mass was well circumscribed with dense connective tissue. Neoplastic areas contained irregular sized mammary gland with papillary grown luminal epithelial cells in single or double cells layer with mitotic figures and small amounts of proliferated myoepithelial cells. Proliferated myoepithelial cells also produced slightly basophilic mucinous materials. Based on the gross, histopathologic and special staining characteristics, this dog was diagnosed as 90% of apocrine sweat gland aenocarcinoma and 10% mammary. complex adenomas in mammary masses. In our best knowledge, this is the first report for concurrent occurrence of apocrine sweat gland adenocarcinoma and mammary gland complex adenoma in mammary masses of the same dog.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.64.2-64.2
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• 2016

Optical variability is one way to probe the nature of the central engine of AGN at smaller linear scales and previous studies have shown that optical variability is more prevalent at longer timescales and at shorter wavelengths. Especially, intra-night variability can be explained through the damped random walk model but small samples and inhomogeneous data have made constraining this model hard. To understand the properties and physical mechanism of optical variability, we are performing the KMTNet Active Nuclei Variability Survey (KANVaS). Test data of KMTNet in the COSMOS field was obtained over 2 separate nights during 2015, in B, V, R, and I bands. Each night was composed of 5 and 9 epochs with ~30 min cadence. To find AGN in the COSMOS field, we applied multi-wavelength selection methods. Different selection methods means we are looking different region in unification model of AGN, and 100~120, 400~500, 50~100 number of AGN are detected in X-ray, mid-infrared, and radio selection of AGN, respectively. We performed image convolution to reflect seeing fluctuation, then differential photometry between the selected AGN and nearby stars to achieve photometric uncertainty ~0.01mag. We employed one of the standard time-series analysis tools to identify variable AGN, chi-square test. Preliminarily results indicate that intra-night variability is found for X-ray selected, Type1 AGN are 23.6%, 26.4%, 21.3% and 20.7% in the B, V, R, and I band, respectively. The majority of the identified variable AGN are classified as Type 1 AGN, with only a handful of Type 2 AGN showing evidence for variability. The work done so far confirms that there are type and wavelength dependence of intra-night optical variability of AGN.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.530-534
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• 2011

This paper reports two cases of schwannomas arising from the oral cavity. One is an intraoral ancient schwannoma located at the left cheek, which evolved over a period of 13 years. The tumor was a well-demarcated buccal mass, which was located in the left lower first premolar area, with an obliterated the buccal vestibule, leaving the overlying mucosa intact. The second case was a central intraosseous schwannoma located from the left lower 1st molar periapical area to the left 3rd molar periapical area. Pathologically, the first mass was composed of the spindle shaped tumor cells with wavy nuclei beneath the fibroconnective tissue of the gingiva but second case mass was not. Occasional nuclear pleomorphism was observed but mitosis or necrosis was absent. There were Antoni A and B areas along with strong, diffuse staining with the S-100 protein. Ancient schwannomas were diagnosed. Schwannoma is a slow-growing benign tumor, and an ancient schwannoma that shows cellular atypism is a variant of a schwannoma caused by purely degenerative changes. To date, only limited cases of ancient schwannomas in the oral cavity have been reported.

• Molecules and Cells
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• v.37 no.7
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• pp.526-531
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• 2014

Human PARP family consists of 17 members of which PARP-1 is a prominent member and plays a key role in DNA repair pathways. It has an N-terminal DNA-binding domain (DBD) encompassing the nuclear localisation signal (NLS), central automodification domain and C-terminal catalytic domain. PARP-1 accounts for majority of poly-(ADP-ribose) polymer synthesis that upon binding to numerous proteins including PARP itself modulates their activity. Reduced PARP-1 activity in ageing human samples and its deficiency leading to telomere shortening has been reported. Hence for cell survival, maintenance of genomic integrity and longevity presence of intact PARP-1 in the nucleus is paramount. Although localisation of full-length and truncated PARP-1 in PARP-1 proficient cells is well documented, subcellular distribution of PARP-1 fragments in the absence of endogenous PARP-1 is not known. Here we report the differential localisation of PARP-1 Nterminal fragment encompassing NLS in PARP-$1^{+/+}$ and PARP-$1^{-/-}$ mouse embryo fibroblasts by live imaging of cells transiently expressing EGFP tagged fragment. In PARP-$1^{+/+}$ cells the fragment localises to the nuclei presenting a granular pattern. Furthermore, it is densely packaged in the midsections of the nucleus. In contrast, the fragment localises exclusively to the cytoplasm in PARP-$1^{-/-}$ cells. Flourescence intensity analysis further confirmed this observation indicating that the N-terminal fragment requires endogenous PARP-1 for its nuclear transport. Our study illustrates the trafficking role of PARP-1 independently of its enzymatic activity and highlights the possibility that full-length PARP-1 may play a key role in the nuclear transport of its siblings and other molecules.

• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.715-725
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• 1994

The ultrastructural investigations of the parotid gland of Korean native goat were carried out by transmission electron microscopy. The results were as follows; 1. The acini of parotid gland were composed of light and dark acinar cells. 2. In the light acinar cells, the secretory granules were classified into three types according to their electron densities and dense bodies. One type of granules was low electron density and had no dense bodies. Another type was low electron density and had dense bodies, and the other type was low electron density and had granular dense bodies. 3. The secretory granules of dark acinar cells showed high electron density and were also calssified into three types by dense bodies as the same way as in the light acinar cells. 4. The intercalated ducts consisted of simple cuboidal epithelium. The nuclei of epithelial cells were oval or round form, located at the central part, and had infolding nuclear membranes and one or two nucleoli. 5. The cells of both of the striated and excretory ducts were composed of light cells, dark cells, specific light cells and basal cells. 6. The nerve terminals were distinguished into two types. One had large granular synaptic vesicles, and another had small agranular synaptic vesicles.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.45.1-45.1
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• 2017

Optical variability is one way to probe the nature of the central engine of AGN at smaller linear scales, and previous studies have shown that optical variability of AGN is more prevalent at longer timescales and at shorter wavelengths. To understand the properties and physical mechanism of variability, we are performing the KMTNet Active Nuclei Variability Survey (KANVaS). Especially, we investigated intra-night variability of AGN with KMTNet data which observed COSMOS field during 3 separate nights from 2015 to 2016 in B, V, R, and I bands. Each night was composed of 5, 9, and 11 epochs with 20-30 min cadence. To find AGN in the COSMOS field, we applied multi-wavelength selection methods. Using X-ray, mid-infrared, and radio selection methods, 50-60, 130-220, 20-40 number of AGN are detected, respectively. Achieving photometric uncertainty ~0.01mag by differential photometry, we employed a standard time-series analysis tool to identify variable AGN, chi-square test. Preliminary results indicate that there is no evidence of intra-night optical variability of AGN. It is possible that previous studies discovered intra-night variability used inappropriate photometric error. However, main reason seems that our targets have fainter magnitude (higher photometric error) than that of previous studies. To discover variability of AGN, we will investigate longer timescale variability of AGN.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.3
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• pp.95-99
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• 2008

Calcium ($Ca^{2+}$) is an intracellular second messenger associated with neuronal plasticity of the central nervous system. The calcium-binding proteins regulate the $Ca^{2+}$-mediated signals in the cytoplasm and buffer the calcium concentration. This study examined temporal changes of three calcium-binding proteins (calretinin, calbindin and parvalbumin) in the medial vestibular nucleus (MVN) during vestibular compensation after unilateral labyrinthectomy (UL) in rats. Rats underwent UL, and the changes in the expression of these proteins at 2, 6, 12, 24, 48, and 72 h were examined by immuno-fluorescence staining. The expression levels of all three proteins increased immediately after UL and returned to the control level by 48 h. However, the level of calretinin showed changes different from the other two proteins, being expressed at significantly higher level in the contralateral MVN than in the ipsilateral MVN 2 h after UL, whereas the other two proteins showed similar expression levels in both the ipsilateral and contralateral MVN. These results suggest that the calcium binding proteins have some protective activity against the increased $Ca^{2+}$ levels in the MVN. In particular, calretinin might be more responsive to neuronal activity than calbindin or parvalbumin.

• Korean Journal of Veterinary Research
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• v.49 no.2
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• pp.157-161
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• 2009

A 11-year-old female mixed cat with subcutaneous mass around the left 5th mammary glands was presented to local animal hospital. According to history taking, the mass recurred 2 times on the same site of abdomen. After surgical excision, subcutaneous mass was referred to Pathology Department of Veterinary Medicine in the Jeju National University. Grossly, round to oval, milky yellow or pale red nodules, measuring 0.1${\sim}$1 cm in diameter, were occupied in the subcutis. Microscopically, the most neoplastic sweat glands were proliferated in the dermis and subcutis. Most tubules were lined by round to oval shaped epithelium with eosinophilic cytoplasm, hyperchromatic nuclei with high mitotic figures and severe central necrosis. The neoplastic epithelium also had periodic acid-Schiff-positive diastase-resistant cytoplasmic granules, but was negative for Perl's iron stain. Based on the gross, histopathologic and special staining, this cat was diagnosed as apocrine sweat gland adenocarcinoma. In our best knowledge, this is the first report of apocrine sweat gland adenocarcinoma around abdominal mammary gland in a cat.

• Journal of Biomedical Engineering Research
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• v.23 no.1
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• pp.39-47
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• 2002

The objective of this study is to provide a Precise form of spatial normalization with affine transformation. The quantitative comparison of the brain architecture across different subjects requires a common coordinate system. For the common coordinate system, not only global brain but also a local region of interest should be spatially normalized. Registration using mutual information generally matches the whose brain well. However. a region of interest may not be normalized compared to the feature-based methods with the landmarks. The hybrid method of this Paper utilizes feature information of the local region as well as intensity similarity. Central gray nuclei of a brain including copus callosum, which is used for feature in Schizophrenia detection, is appropriately normalized by the hybrid method. In the results section. our method is compared with mutual information only method and Talairach mapping with schizophrenia Patients. and is shown how it accurately normalizes feature .