• Applied Microscopy
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• v.26 no.1
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• pp.67-77
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• 1996

Pancreases obtained from native Korean goats were used, and examined by immunoelectron microscopy using several antisera. Five types cells, glucagon (A), insulin (B), somatostatin (D), and pancreatic polypeptide (PP-I and PP-II) cells, were identified in the pancreatic islets. The morphologies of A, B, and D cells corresponded to the typical charateristics described in previous reports on other mammals. Serotonin immunoreactivity was observed in the D cells on the basis of the granular profiles. Two types of PP cells could be distinguished on the basis of the granular profile: the first type was formed by round, homogeneous secretory granules ($220{\sim}400nm$) having a narrow halo between the dense core and limiting membrane, while the other type consisted of cells whose secretory granules ($240{\sim}440\;nm$ in the major axis, $150{\sim}200nm$ in the minor axis) were pleomorphic, having a dense core and a closely fitting limiting membrane. From these results, we suggest that the pancreatic islets of the native Korean goat consist of five types of endocrine cells, A, B, D, PP-I and PP-II cells. Among these, PP-I type cells may correspond to the classical PP of other mammalian pancreases, while PP-II type cells may correspond to the enterochromaffin cells in other species.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.6
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• pp.878-885
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• 2017

Objective: Glucose is an essential fuel in the energy metabolism and synthesis pathways of all mammalian cells. In lactating animals, glucose is the major precursor for lactose and is a substrate for the synthesis of milk proteins and fat in mammary secretory (alveolar) epithelial cells. However, clear utilization of glucose in mammary cells during lactogenesis is still unknown, due to the lack of in vitro analyzing models. Therefore, the objective of this study was to test the reliability of the mammary alveolar (MAC-T) cell as an in vitro study model for glucose metabolism and lactating system. Methods: Undifferentiated MAC-T cells were cultured in three types of Dulbecco's modified Eagle's medium with varying levels of glucose (no-glucose: 0 g/L, low-glucose: 1 g/L, and high-glucose: 4.5 g/L) for 8 d, after which differentiation to casein secretion was induced. Cell proliferation and expression levels of apoptotic genes, Insulin like growth factor-1 (IGF1) receptor, oxytocin receptor, ${\alpha}S1$, ${\alpha}S2$, and ${\beta}$ casein genes were analyzed at 1, 2, 4, and 8 d after differentiation. Results: The proliferation of MAC-T cells with high-glucose treatment was seen to be significantly higher. Expression of apoptotic genes was not affected in any group. However, expression levels of the mammary development related gene (IGF1 receptor) and lactation related gene (oxytocin receptor) were significantly higher in the low-glucose group. Expressions of ${\alpha}S1-casein$, ${\alpha}S2-casein$, and ${\beta}-casein$ were also higher in the low-glucose treated group as compared to that in the no-glucose and high-glucose groups. Conclusion: The results demonstrated that although a high-glucose environment increases cell proliferation in MAC-T cells, a low-glucose treatment to MAC-T cells induces higher expression of casein genes. Our results suggest that the MAC-T cells may be used as an in vitro model to analyze mammary cell development and lactation connected with precise biological effects.

• Applied Microscopy
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• v.19 no.2
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• pp.119-137
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• 1989

It has been shown in this and earlier investigation that the turtle bladder mucosa has three main cell types on their mucosal surface. They are the granular cells, ${\alpha}$ CA cells, and ${\beta}$ CA cells. The three major transport mechanisms that occurs in the turtle bladder are sodium reabsorption, proton secretion, and bicarbonate secretion. In the present work the trans-port mechanisms by bladder epithelial cells of freshwater turtle, Pseudemys scripta, are summarized as follows. 1. The granular cells play an important role in sodium transport, while the ${\alpha}$ and ${\beta}$ CA cells do not appear to play a determining role in sodium transport. 2. It appears that the active sodium transport in the granular cells occurs in two-step process, implying that first, sodium diffuses into the cells, followed by an energy-dependent efflux step, which is catalyzed by the ouabain-sensitive Na-K ATPase. 3. The ${\alpha}$ type of CA cells are responsible for the proton secretion using the proton pump on the apical plasma membrane, while the ${\beta}$ type of CA cells are believed to be responsible for bicarbonate secretion. 4. When looked at under freeze-fracture electron microscopy, the apical plasma membrane of ${\alpha}$ cells have a characteristic population of rod-shaped intramembranous particles which are believed to be components of the proton pumps. Conversely, ${\beta}$ type of CA cells show rod-shaped particles in their basolateral plasma membranes, which is consistent with the proton absorptive, bicarbonate secretory mechanism. 5. In the turtle bladder, the ${\alpha}$ and ${\beta}$ type of cells are believed to be both responsible for proton transport, but in opposite directions.

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.895-902
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• 2002

Monocytes and macrophages playa major role in defense mechanism of the host response to tumor, in part through the secretion of several potent products and macrophage cytokines. Monocytes and tissue macro phages produce at least two groups of protein mediators of inflammation, interleukin 1 (IL-1) and tumor necrosis factor (TNF). Recent studies emphasizes that TNF and IL-1 modulate the inflammatory function of endothelial cells, leukocytes, and fibroblasts. In this study, our work is directed toward studying the in vitro effects of Korean propolis on the ability to induce cellular and secretory responses in murine macrophage cell line, RAW 264.7. It was found that Water Extract of Korean Propolis (WEP) could activate macro phages by producing cytokines. The production of the macrophage cytokines, IL-1 and TNF-$\alpha$, by RAW 264.7 treated with WEP was examined from 2.5 $\mu\textrm{g}$/ml up to 25 $\mu\textrm{g}$/ml with dose dependent manner. Nitric oxide (NO) production was also increased when cells were exposed to combination of LPS and WEP from 2.5 $\mu\textrm{g}$/ml up to 25 $\mu\textrm{g}$/ml. At high dose of WEP (50 to 100 $\mu\textrm{g}$/ml) used to prescribe for anti-inflammatory and analgesic medicine showed inhibition of NO production in LPS-stimulated macrophage. Besides cytokine production, NO release, surface molecule expression and cell morphologic antigen expression were increased in response to the stimulation by WEP. These results suggested WEP may function through macrophage activation.

• Applied Microscopy
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• v.14 no.2
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• pp.29-37
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• 1984

Morphological changes of the epithelium of the endometrium by prolonged treatment of $17{\beta}$-estradiol or progesterone in ovariectomized rats was studied at the ultrastructural level. The epithelium of the endometrium in ovariectomized rats was characterized by the appearance of a number of vacuoles which was contained with the membraneous structures, lipid droplets and the others. The epithelium was low cuboidal, and a few short microvilli were present at the cell surface. Secretory granules are rarely found. After estradiol treatment, the epithelium was high columnar in shape. The mitochondria was appeared throughout the cytoplasm, however, long or swelling mitochondria was often found. Golgi apparatus and rER were relatively well-developed. Relatively long and sparse microvilli were present at the cell surface. After progesterone treatment, the epithelium was characterized by the appearance of numerous vesicles at the apical region and numerous lipid droplets at the subnuclear region. At the cell surface a number of short and blunt microvilli were found. These data indicated that the endometrium was dependent on estrogen and progesterone for changes in both its morphological and functional state and suggested that each hormone exerted a unique effect on the epithelial cells.

• Molecules and Cells
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• v.19 no.2
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• pp.185-190
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• 2005

The chicken oviduct is a dynamic organ that produces secretory proteins such as ovalbumin and its cells undergo cell proliferation and differentiation. There has been no study of the cellular mechanism involved in cell death in the chicken oviduct. Therefore, this study has focused on the study of apoptosis in primary oviduct cells. Because ceramide is known to activate apoptosis in tumor cells and is produced in the oviduct, we used an exogenous ceramide analog to induce cell death. The viability of ceramide-treated chicken oviduct cells decreased in a dose-dependent manner and apoptotic cells were detected by staining with annexin V. The expression of apoptosis-related genes was assessed by RT-PCR and bcl-2 mRNA was found to decrease after exposure to ceramide while Bcl-x mRNA increased 12 h post-treatment. In addition, caspase-3 was expressed strongly in the early stages of apoptosis, while caspase-1 and -9 transcripts increased at later times. We conclude that ceramide induces apoptosis in oviduct-derived primary cells via a caspase- and bcl-2-dependent pathway.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.113-121
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• 2011

Foot-and-mouth disease (FMD) is a severe vesicular disease of cloven-hoofed animals including domesticated ruminants and pigs. Acute clinical signs may be mild in sheep and goats but are associated with lameness in pigs and mouth lesions with vesicles in cattle. The required condition for a successful pathogen appears to be the ability to counteract both the host innate and adaptive immune response. FMD virus (FMDV) inhibits the induction of antiviral molecules and interferes with the secretory pathway in the infected cell. The surface expression of Major Histocompatibility Complex (MHC) class I molecules is reduced in infected cells. Thus, the ability of the host to recognize and eliminate virus infected cells is decreased. Furthermore, FMDV infection results in a rapid, but transient lymphopenia, reducing the number of T and B cells, and affecting T cell function. The virus appears to premature apoptosis-mediated cell death because it has a very short replication cycle and is able to rapidly produce large amounts of virus. FMDV engages the host protective response at multiple steps to ensure its effective replication and pathogenesis. This review describes the recent pathological and immunological studies to overcome the powerful abilities of FMDV to counteract defense mechanism of host.

• Korean Journal of Ichthyology
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• v.28 no.3
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• pp.147-155
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• 2016

This study describes the cell type, ultrastructure and histochemical characteristics as a preliminary study for the research on integument of the smooth lumpsucker, Aptocyclus ventricosus in accordance with the physiological and environmental changes using light and electron microscopes. The SEM revealed the presence of well-developed finger printing structure in the skin surface. The skin surface of the smooth lumpsucker showed an irregular folds in cross section of light microscope. Integument is composed of outer epidermal and inner dermal layer. The epidermal layer is a stratified layer composed of epithelial cells, mucous cells, vacuolar cells, and granular cells. Epithelial cells are classified into superficial, intermediated, and basal cell. The superficial cells were the squamous with well-developed microridges on the free surface, and the microridges were covered with glycocalyx. The mucous cells of unicellular gland were mainly distributed in the apical layer of epidermis and contained mucosal materials of neutral glycoprotein. The vacuolar cells of unicellular gland were mainly distributed in the mid and basal layer of epidermis. The proportion of mucous cells and vacuolar cells were $7.0({\pm}1.07)%$ and $40.6({\pm}3.31)%$ of epidermal area, respectively. The granular cells contained membrane bounded secretory granules with high electron density and developed cell organelles in the cytoplasm. The dermal layer was loose connective tissue layer and composed of mainly collagen fibers. It also contained blood vessels and chromatophores of melanophores and reflecting platelets.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.2
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• pp.149-154
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• 2005

Secretion of the expressed heterologous proteins can reduce the stress to the host cells and is beneficial to their recovery and purification. In this study, fed-batch cultures of Escherichia coli YK537 (pAET-8) were conducted in a 5-L fermentor for the secretory production of human epidermal growth factor (hEGF) whose expression was under the control of alkaline phosphatase promoter. The effects of feeding of glucose and complex nitrogen sources on hEGF production were investigated. When the fed-batch culture was conducted in a chemically de-fined medium, the cell density was 9.68 g/L and the secreted hEGF was 44.7 mg/L in a period of 60 h. When a complex medium was used and glucose was added in pH-stat mode, the secreted hEGF was improved to 345 mg/L. When the culture was fed with glucose at a constant specific rate of $0.25\;gg^{-1}h^{-1}$, hEGF reached 514 mg/L. The effects of adding a solution containing yeast extract and tryptone were further studied. Different rate of the nitrogen source feeding resulted in different levels of phosphate and acetic acid formation, thus affected hEGF expression. At the optimal feeding rate, hEGF production achieved 686 mg/L.

• Applied Microscopy
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• v.29 no.2
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• pp.231-239
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• 1999

Morphological changes of Drosophila ocellar corneagenous cells were studied to the development with electron microscopy, and the movement of produced proteins was traced with autoradiography. Corneagenous cells of immediate postemergence showed very active secretion pattern. However, a few days after the emergence, the secretory activity of corneagenous cell was supposed to be dropped suddenly. In autoradiography, almost of proteins that produced by corneagenous cells moved toward lens. From this, it was supposed that the corneagenous cells do not function in photoreceptor cells rather in the formation of lens at the postemergence stage. Corneagenous cells of pupal stage were well developed. In the period of lens formation, rER of corneagenous cells were well developed and it suggested very active material metabolism. Granules and microtubules were also frequently observed and the later would be a pathway of the movement of materials. In conclusion, corneagenous cells were well developed at vigorous lens forming stage. After emergence, when the lens formation was completed, both the function and the size of corneagenous cells were reduced.