• ALGAE
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• v.31 no.4
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• pp.379-390
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• 2016

When a multinucleate cell of Bryopsis plumosa was collapsed by a physical wounding, the extruded protoplasm aggregated into numerous protoplasmic masses in sea water. A polysaccharide envelope which initially covered the protoplasmic mass was peeled off when a cell membrane developed on the surface of protoplast in 12 h after the wounding. Transmission electron microscopy showed that the protoplasmic mass began to form a continuous cell membrane at 6 h after the wounding. The newly generated cell membrane repeated collapse and rebuilding process several times until cell wall developed on the surface. Golgi bodies with numerous vesicles accumulated at the peripheral region of the rebuilding cell at 24 h after the wounding when the cell wall began to develop. Several layers of cell wall with distinctive electron density developed within 48-72 h after the wounding. Proteome profile changed dramatically at each stage of cell rebuilding process. Most proteins, which were up-regulated during the early stage of cell rebuilding disappeared or reduced significantly by 24-48 h. About 70-80% of protein spots detected at 48 h after the wounding were newly appeared ones. The expression pattern of 29 representative proteins was analyzed and the internal amino acid sequences were obtained using mass spectrometry. Our results showed that a massive shift of gene expression occurs during the cell-rebuilding process of B. plumosa.

• KSBB Journal
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• v.11 no.3
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• pp.288-294
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• 1996

We have investigated the characteristics of recombinant CHO cell growth and erythropoletin(EPO) production at different concentrations of serum and inoculation density. Cell growth and EPO production were increased with the increase of serum concentration and inoculation density. Enhancement of CHO cell growth and EPO production by medium exchange using serum-free medium at the growth phase of cells was studied. It was found that the exchange of culture medium with serum-free medium was favorable for growth of cells and production of EPO. The maximum number of cell and concentration of EPO obtained by exchanging culture medium were $6.2{\times}105cells/$\textrm{cm}^2$ and 7,470units/m1, respectively, compared to $2.1{\times}105cells/\textrm{cm}^2$ and 2,380units/m1 in serum-containing medium without medium exchange. It was observed that CHO cell growth was correlated with EPO production in serum-free media.

• Journal of the Korean Institute of Gas
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• v.5 no.4 s.16
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• pp.79-84
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• 2001

In this study, the effect of polyol structure(OH-value, functionality) on the reactivity, mechanical property and cell morphology of polyurethane foam and the possibility of replacing HFC-36smfc was examined by evaluating how each blowing agent(CFC-11, HCFC-l4lb, HFC-36smfc) affects the reactivity, mechanical property and cell morphology. Results of the experiment showed that as the functionality and OH-value of polyol increased, there was an increase in the temperature profile, reaction rate, density and compressive strength. However. as the functionality and OH-value increased. the ceil size became smaller The use of different kinds of blowing agents did not appear to have and significant influence on the temperature profile, reaction rate, density and compressive strength. The foam using HFC-365mfc produced more uniform cells compared to the foam using HCFC-l4lb.

• Applied Microscopy
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• v.26 no.3
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• pp.305-313
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• 1996

Acinous gland cells (A, B, C, D and E-type cells) and duct cell (G-type cell) are observed in acinus and in duct of salivary gland of Korean Slug respectively by electron microscope. The type-A gland cells are numerous and are packed with medium electron dense granules (diameter, $3{\mu}m$) in cytoplasm. The circular shaped nucleolus and evenly developed chromatins are observed in the nucleus of type-B cell, and cytoplasm includes medium electron dense granules (diameter, $2.5X3.7{\mu}m$). The type-C gland cell has a round nucleus, and thin elongated-shaped heterochromatins are evenly distributed in the nucleoplasm and many net shaped endoplasmic reticulums and oval serous granules of middle electron density (diameter, $3.5X5{\mu}m$) fill the cytoplasm. The type-D gland cell is the largest and the most numerous of the gland cells consisting the salivary gland and heterochromatins in nucleus are well developed in the nucleoplasm. Most of granules (diameter, $0.8X2.5{\mu}m$) in cytoplasm are round, and look dark for the high electron density, and cytoplasm is filled with net-shaped endoplasmic reticulums. The type-E gland cells are rarely existent around the salivary gland, and the granules of those cells are irregular in shape and size and are vacuolized in cytoplasm. Intralobular salivary duct is composed of the high electron dense squamus endotheliums, while the other interlobular salivary duct is filled with irregular columnar epitheliums. The interlobular duct cell contains the high electron dense granules (size, $0.3{\sim}1.5{\mu}m$) in cytoplasm and those granules are secreted into cilia of salivary lumen.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.6
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• pp.495-505
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• 2006

In this study we evaluate the effects of bFGF-BB and PDGF on in vitro proliferation, differentiation and mineralization of mesenchymal stem cells (MSCs) from rat. MSCs were prepared from the bone marrow of 6 or 7-week-old male rats with a technique previously described by Maniatopoulos et al. in 1988. Lineage differentiation to osteogenesis, chondrogenesis and adipogenesis were performed. At first, we characterized the cultured cell on passage 1, 3, 5, 7 with immunocytochemical staining using CD29, 44, 34, 45, ${\alpha}$-SMA and type I collagen. And to study the effects of bFGF and PDGF-BB on proliferation, differentiation and mineralization, we seeded the expanded cell at a density of 6 $6{\times}10^3\;cells/cm^2$ to 100-mm dish for evaluation of cell proliferation and MTT assay was carried out on day 2, 4, 7, 9. We also resuspended the cells with same density $(6{\times}10^3\;cells/cm^2)$ to 24 well plates for subculture. On the following day, the attached cells were exposed to 2.5ng/ml bFGF and/or 25ng/ml PDGF-BB daily during 5 days. The osteocalcin (OC) level was assessed and mineral contents were evaluated with alizarin red S staining on subculture day 2, 7, 14, 21. We identified the mesenchymal stem cell from the bone marrow derived cells of rat through their successful multi-differentiation and stable display of its phenotype. And bFGF and PDGF-BB showed the effect that inhibited osteoblastic differentiation and mineralization mildly in above concentration at in vitro culture. This study was supported by grant 04-2004-0120 from the Seoul National University Hospital Research Fund.

• Molecules and Cells
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• v.19 no.3
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• pp.382-390
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• 2005

Calcium-binding proteins are thought to play important roles in calcium buffering. The present study investigated the effects of ischemia and reperfusion on calbindin D28K, calretinin, and parvalbumin immunoreactivity in the ganglion cell layer of the rabbit. Rabbits were administered ischemic damage by increasing the intraocular pressure. After 60 and 90 min of ischemia, reperfusion (7 d) was allowed to occur. The b-wave of the electroretinogram (ERG) was reduced by more than 50% and almost 80% in retina given ischemia for 60 and 90 min, respectively. The oscillatory potential (OPs) wave was reduced approximately 50% at 60 min ischemia and 70% at 90 min ischemia. In both normal and ischemic-treated retina, calcium-binding protein immunoreactivity was seen in many cells in the ganglion cell layer. In eyes subjected to 60 min ischemia, there was a decrease of the density of calbindin D28K- (8.29%), calretinin- (14.44%), and parvalbumin- (26.83%) immunoreactive (IR) cells compared to the control retina. In eyes subjected to 90 min ischemia, there was a higher decrease of the density of calbindin D28K- (18.48%), calretinin- (33.59%), and parvalbumin- (54.26%) IR cells than at 60 min. Some calcium-binding protein-IR neurons, especially calretinin-IR neurons, showed aggregations that were abnormally packed together in retina subjected to ischemia for 90 min. The results show that calbindin D28K-, calretinin-, and parvalbumin-IR cells in the ganglion cell layer are susceptible to ischemic damage and reperfusion. The degree of reduction varied among different calcium-binding proteins and ischemic damage times. These results suggest that calbindin D28K-containing neurons are less susceptible to ischemic damage than calretinin- and parvalbumin-containing neurons in the ganglion cell layer of rabbit retina.

• KSBB Journal
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• v.13 no.4
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• pp.404-410
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• 1998

Three types of adsorbents were developed by immobilizing synthetic zeolite, Philipsite-Gismonine, in alginate, cellulose acetate and dialysis membrane for the in situ removal of ammonium ion which inhibits growth and productivity of animal cells such as CHO cells producing tPA. Ammonium ion removal efficiency and cell growth promoting effect with various immobilized adsorbents were evaluated and the membrane type was selected as an optimal immobilized adsorbent. The experiments were then simulated by adding 8mM ammonium chloride and immobilized adsorbent in order to validate the removal effect under high density cell cultures. The results showed increase in maximum cell density by three times, in cell viability, and in tPA productivity by 40%. And it was found that the promoting effects were more significant in case of high ammonium ion concentration system. It was also found that the optimum addition time for immobilized adsorbents was 48 hr in the absence of ammonium chloride addition and 72 hr in the presence of ammonium chloride addition.

• The Journal of Korean Medicine
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• v.41 no.4
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• pp.27-40
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• 2020

Objectives: This study was conducted to evaluate the hair growth-promoting effects by Rumex japonicas Houttuyn ethanol extract (RJHEE) in C57BL/6N mice and HaCaT cells. Methods: The hair growth effect was examined by topical application of RJHEE on the shaved dorsal skin of C57BL/6 mice. Six-week old mice were depilated and separated in 4 groups; CON (vehicle treatment), MXD (2% Minoxidil), and RJHEE (2% and 4%). The treatments were applied daily for 17 days. The hair growth was determined photographically and the hair density, thickness and length were identified by Folliscope. In dorsal skin tissue, the expression of hair growth-related protein was analyzed by Western blotting. In HaCaT cells, the cell proliferation and the protection against H₂O₂-induced cell damage by RJHEE were analyzed. Results: Our results indicate that RJHEE promote the hair growth, hair density, thickness and length. RHE activate the Wnt/𝛽-catenin signaling and induced the expression of cell survival-related proteins, such as pERK/ERK and Bcl-2/Bax. In HaCaT, RJHEE accelerated the cell proliferation and protected the H₂O₂-induced cell damage. Conclusions: Our results strongly suggest that RJHEE promotes hair growth by regulating the activation of Wnt/𝛽-catenin signaling and cell survival signaling and protects oxidative stress-induced hair damage. Therefore, RJHEE has a hair growth activity and can be useful for the treatment of alopecia.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.163-172
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• 2004

Mast cells (MCs) have been implicated in the pathogenesis of tissue fibrosis. However, the role of MC in the development of liver fibrosis has not been fully elucidated. Stem cell factor (SCF) is known to recruit MCs to the liver following injury as it induces mast cell proliferation, survival and differentiation from resident tissue precursors. This study examines the interaction between activated hepatic stellate cells (HSCs) and MCs in rat fibrotic liver, and SCF production by HSCs during culture in vitro. Rats were studied 4, 7, 14 and 21 days after bile duct ligation (BDL). Fibrogenesis was assessed by a measurement of collagen stained with sirius red F3B. Activated HSCs and MCs were identified by ${\alpha}$-smooth muscle actin (${\alpha}-SMA$) immunohistochemical and alcian blue staining and measured by a computerized image analysis system. SCF production was determined in rat HSC cultures using Western blotting. Mild fibrotic changes were noted in BDL rat livers as early as 4 days after induction of cholestasis. Significant expansion and organization of fibrous tissue has occurred in day 14 BDL rats which progressed to bridging fibrosis by day 21. In BDL rats, both a large number of activated HSCs and MCs were detected in portal tracts and fibrous septa. Both area of activated HSCs infiltration and density of MCs were significantly higher in all BDL group compared with Shams. In BDL rats, both areas of activated HSCs infiltration and density of MCs were no significant difference between day 4 and 7 and were significantly higher in day 14. However, the areas of activated HSCs infiltration were significantly lesser in day 21 and the densities of MCs were significantly higher in day 21 compared with day14 BDL. In BDL rats, both areas of activated HSCs infiltration and density of MCs were highly correlated with areas of fibrosis. Western blotting showed that SCF protein was consistently produced in activated HSCs by culture on plastic and freshly isolated HSCs expressed relatively little 30kD SCF compared to late primary culture activated HSCs (day 14) and passaged HSCs. These results suggest that HSCs activated in vitro produce SCF, and may play an important role in recruiting mast cells to the liver during injury and fibrosis.

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.245-250
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• 1992

This study was performed to demonstrate the presence of large granular lymphocyte(LGL) in Sprague-Dawley(SD) rats and morphologically observe NK cell and also establish the method of isolation of natural killer cell in SD rats. By percoll discontinuous density gradients centrifugation, highly enriched LGL population were shown to fraction 2(border line between 44.2% and 50.8%). LGL were shown to bind selectively to YAC1 mouse lymphoma cell. This fraction expressed very high NK cell cytolysis. Therefore, we thought that LGL have NK activity in SD rats. The Morphology of rat LGL is very similar to that of human LGL. These cells have an eccentric kidney-shaped nucleus. Their most distinctive feature was their cytoplasmic azurophilic granules. Another distinguishing feature of rat LGL was their high cytoplasmic : nuclear ratio. It was concluded that LGL played a role part in mediating natural killer activity in this species.