• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.137-143
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• 2009

It has been reported that mechanical stimulation takes a role in improving eel/ growth in skeletal system. Various research groups have been showed their own bioreactors which stimulate cell-seed three-dimensional scaffold. In this study, we hypothesized that the various conditions of mechanical stimulation would affect cell growth and proliferation. To prove our hypothesis, we designed a custom-made bioreactor capable of applying controlled compression to cell-encapsulated scaffolds. This device consisted of a circulation system and a compression system. Each parts of the bioreactor was fabricated using the rapid prototyping technology By using the rapid prototyping technology, we can modify and improve the bioreactor very rapidly For dynamic cell-culture, cell-encapsulated agarose gel was fabricated in 2% concentration. We performed dynamic cell-culture using this agarose gel and developed bioreactor in 3 days.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1257-1262
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• 2005

MMP-9 is a metalloproteinase capable of basement membrane degradation in vivo. Expression of MMP-9 can be found in normal conditions such as trophoblasts, osteoclasts, and leukocytes and their precursors. They also occur as well as in pathological conditions, such as the invasive growth of primary tumors, metastasis, angiogenesis, rheumatoid arthritis, and periodontal diseases. MMP-9 upregulation can be highly induced by a wide range of agents. These agents include growth factors, cytokines, cell-cell, and cell-ECM adhesion molecules, and agents altering cell shape. Here, we observed that TNF-$\alpha$ stimulated human monocytic cell line, HL-60 produced MMP-9 in a dose and time dependent manner. Real time PCR results indicated transcriptional upregulation of MMP-9 as early as 3 h post TNF-$\alpha$ stimulation. To investigate the signaling pathway underlined in TNF-$\alpha$ induced MMP-9 expression, three MAP kinase inhibitors were added to cells 1 h prior to TNF-$\alpha$ treatment. The ERK inhibitor completely abolished MMP-9 expression by TNF-$\alpha$. But neither p38 MAP kinase nor JNK inhibitor had an effect on TNF-$\alpha$ induced MMP-9 expression, suggesting that ERK activation is required for the MMP-9 induction by TNF-$\alpha$. Taken together, we found that TNF-$\alpha$ stimulation facilitates ERK activation, which results in the transcriptional upregulation of MMP-9 gene and subsequent MMP-9 production and secretion.

• Child Health Nursing Research
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• v.10 no.2
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• pp.180-187
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• 2004

Purpose: This study was designed to investigate effect of sensory stimulation on the mother-infant interaction in premature infants. Method: The subjects of this study consisted of 36 pairs of premature infants and their mothers from NICU of one university hospital located in Taegu, 18 pairs for intervention group and 18 pairs for control group. The data were collected from May, 1999 to October, 2000. For the intervention group Field's sensory stimulation(tactile and kinesthetic stimulation) was applied 2 times a day for 10 days(10:00-11:00 in the morning and 7:00-8:00 in the afternoon by researcher and mother). To determine mother and infant interaction during feeding, tool developed by Kim Mi-Ye(1999) was used. Collected data were analyzed with SAS program using chi-square test and t-test. Result: Significant differences were found in mother-infant interaction between two groups(t=-5.38, p=.00). It indicates that sensory stimulation was effective in improving mother-infant interaction. In the aspects of the quality of mother-infant interaction, sensory stimulation was most effective in improving sensitivity to mother and infant's synchronic behaviors(t=-5.43. p=.00) and followed by growth fostering(t=-5.07, p=.00), sensitivity to infant's cues(t=-4.53, p=.00), clarity of infant's cues(t=-3.03, p=.00) and responsiveness to the mother's behaviors(t=-2.14, p= 0.04). Conclusion: Based on the result of this study, it is suggested that maternally administered sensory stimulation should be applied clinical practice to improve interaction of premature infants and their mothers.

• The Journal of Korean Physical Therapy
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• v.19 no.4
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• pp.33-41
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• 2007

Purpose: To investigate environmental enrichment and nerve stimulation follows in application times with the change of BDNF & Trk-B receptor in the motor cortex and spinal cord. Methods: Experimental groups were divided into the five groups. Group I: normal control group, Group II: experiment control group, Group III: sciatic never electrical stimulation after MCAO, Group IV: application of only environmental enrichment after MCAO, Group V: never electrical stimulation with environmental enrichment after MCAO. Histologic observation and coronal sections were processed individually in goat polyclonal antibody phosphorylated BDNF and rabbit polyclonal antibody Trk-B receptor. Results: In immunohistochemistric response of BDNF and Trk-B, group II were showed that lower response effect at postischemic 1 days, 3 days, and 7 days. Group V were showed that increase response effect at postischemic 3 days, 7 days and 14 days. Specially showed that the most response effect at postischemic 14 days. In neurobehavioral assessment, group V were significantly difference from other groups on between-subject effects. Conclusion: The above results suggest that combined environmental enrichment with peripheral nerve electrical stimulation in focal ischemic brain injury were more improved that the change of BDNF & Trk-B receptor expression than non treatment.

• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.119-126
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• 2015

Among the various human growth factors, epidermal growth factor (hEGF, consisting of 53 amino acids) has various effects on cell regeneration, stimulation of proliferation, migration of keratinocytes, formation of granulation tissues, and stimulation of fibroblast motility, which are important for wound healing. Owing to their multiple activities, EGFs are used as pharmaceutical and cosmetic agents. However, their low productivity, limited target specificity, and short half-life inhibit their application as therapeutic agents. To overcome these obstacles, we fused the collagen-binding domain (CBD) of Vibrio mimicus metalloprotease to EGF protein. About 18 or 12 amino acids (aa) (of the 33 total amino acids), which were essential for collagen-binding activity, were combined with the N- and C-termini of EGF. We constructed, expressed, and purified EGF (53 aa)-CBD (18 aa), EGF (53 aa)-CBD (12 aa), CBD (18 aa)-EGF (53 aa), and CBD (12 aa)-EGF (53 aa). These purified recombinant proteins increased the numbers of cells in treated specimens compared with non-treated specimens and control hEGF samples. The collagen-binding activities were also evaluated. Furthermore, CBD-hybridized hEGF induced phosphorylation of the EGF receptor. These results suggested that these fusion proteins could be applicable as small therapeutic agents in wound tissue healing.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1490-1495
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• 2009

The development of nanotechnology has penetrated the fields of biology and medicine, resulting in remarkable applications for tissue regeneration. In order to apply this technology to tissue engineering, we have developed nano-scaled 3D scaffolds consisting of growth factor-loaded heparin/poly(l-lysine) nanoparticles (NPs) attached to the surface of polymeric micro spheres via polyionic complex methods. Growth factor-loaded NPs were simply produced as polyelectrolyte complexes with diameters of 100-200 nm. They were then coated onto positively charged poly(lactic-co-glycolic acid) (PLGA) pretreated with polyethyleneimine to enable cell adhesion, proliferation, and stimulation of neurite outgrowth. Propidium iodide staining and $\beta$-tubulin analysis revealed that neuronal PC12 cells proliferated extensively, expressed significant amounts of b-tubulin, and showed well-structured neurite outgrowth on polymeric microspheres by stimulation with growth factors. These results suggest that cellular adhesion and biological functionality on prepared PLGA microspheres enabled terminal differentiation of neuronal cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.797-802
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• 2004

L-Ascorbic acid (AsA), commonly known as vitamin C, which is one of the antioxidant vitamins, plays a role in cellular oxidant quenching. Some of the biochemical reactions in which it takes part have been traced through organ culture technique. But in cell cultured system, views on stimulatory and inhibitory action of AsA on cell growth are conflicting. Therefore, this study aimed to clarify the inhibitory action of high concentration AsA on the cell growth in Primary chondrocyte isolated from rat ribs. Cells were exposed to ascorbate at various concentrations. Supplement of AsA induced stimulation of cell growth in primary cultured cells of chondrocytes. Most remarkable stimulation of cell growth by AsA was found in primary cultured chondrocytes. However, it showed that they were dead in the medium which contained AsA at the concentration higher than 1.0 mM. This lethal effect of AsA causing the cell death was inhibited by the addition of catalase in the medium. This supposed that hydroxyl radical (ㆍOH) induced from $H_2O$$_2$ was actively cytotoxic agent. Based on the results, when AsA was added in medium at normal concentrations, the cell growth was stimulated by inducing the formation of extracellular matrix. On the contrary, if added in medium at excess concentrations, the cell growth was inhibited because $H_2O$$_2$ were generated from AsA in medium. Therefore, addition of AsA at the normal concentrations stimulates cell growth, but excess concentrations of AsA induces cell death.

• The Korean Nurse
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• v.24 no.4 s.132
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• pp.21-26
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• 1985

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1411-1414
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• 2008

It is reported that mechanical stimulation takes a role in improving cell growth in skeletal system. And various research groups have showed that developed bioreactor to stimulate cell-seeded and threedimensional scaffold. In this study, we designed a custom-made bioreactor capable of applying controlled compression to cell-seeded agarose gel. This device consisted of a circulation system and compression system. In circular system, culture chamber was sealed for prohibiting contamination and media solution was circulated by pump. In compression system, mechanical stimuli were controlled by LabVIEW software and mechanical transfer system. Cell-encapsulated agarose gels were cultured for up to 7 days. There were significant differences between the number of cells grown in dynamic cell culture and in static cell culture from 3 days to 7 days.

• Journal of fish pathology
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• v.31 no.2
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• pp.109-113
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• 2018

The purpose of the present study was to determine whether the scuticocidal activity of olive flounder (Paralichthys olivaceus) head-kidney leucocytes can be enhanced by stimulation with polyinosine-polycytosine [poly (I:C)]. The growth of Miamiensis avidus was not affected by exposure to unstimulated or poly (I:C)-stimulated leucocytes alone, heat-inactivated immune serum alone, or unstimulated leucocytes plus heat-inactivated immune serum. However, leucocytes stimulated with poly (I:C) showed clearly high scuticocidal activity against M. avidus in the presence of heat-inactivated immune serum. Furthermore, numerous poly (I:C)-stimulated leucocytes occupied the surface of scuticociliates in the presence of the heat-inactivated immune serum, which led to lysis of scuticociliates. These results suggest that both of the stimulation of leukocytes and the immobilization of scuticociliates are necessary to kill scuticociliates by leukocytes.