• Proceedings of the Ginseng society Conference
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• 1980.09a
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• pp.71-76
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• 1980

Aortic strips were prepared from rabbits, and the tensions were maintained by administration of norepinephrine into the incubation chamber. The application of diol or triol induced relaxation of the aortic strip, as indicated by the decreased aortic tension. Triol, in a concentration of $30\;mg\%\;causes\;approximately\;50\%$ of muscle relaxation, whereas a similar degree of relaxation is induced by $50\;mg\%$ of diol. This indicates that both triol and diol cause relaxation of the aorta, but that triol is about $170\%$ more potent than diol. It is well established that blood-vessel smooth-muscle tone is regulated by the available intracellular $Ca^{++}$ concentration, which in turn is profoundly influenced by interaction of the cellular membrane and sarcoplasmic reticulum in the smooth muscle. Thus, any agent which modifies the smooth-muscle tone is expected to interfere with the $Ca^{++}$ binding or uptake of sarcolemma and sarcoplasmic reticulum. In the following experiments sarcoplasmic reticulum and sarcolemma were prepared from the ventricle of rabbit heart, and the active $Ca^{++}$ uptake by these cellular components was measured employing $Ca^{45}$ in the presence of triol and diol. It was found that the active $Ca^{++}$ uptake in the presence of ATP by sarcoplasmic reticulum was inhibited by both triol and diol. Panaxatriol, in a concentration of $80\;mg\;\%,$ inhibited $Ca^{++}$ uptake by $30\%,$ whereas panaxatriol in the same concentration inhibited uptake by $20\%.$ It is clear that triol is a more potent inhibitor of active $Ca^{++}$ transport in sarcoplasmic reticulum than diol. The $Ca^{++}$ binding of the cellular membrane was also studied employing Ca45 and milipore techniques. It was found that triol in a concentration of $80\;mg\;\%,$ decreased $Ca^{++}$ binding by $29\%.$ Diol in the same concentration decreased the binding by $17\%.$ It is clear that both triol and diol inhibit $Ca^{++}$ binding to the cellular membrane, but triol is approximately $180\%$ more potent than diol.

• Journal of Periodontal and Implant Science
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• v.49 no.4
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• pp.258-267
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• 2019

Purpose: Increased bone regeneration has been achieved through the use of stem cells in combination with graft material. However, the survival of transplanted stem cells remains a major concern. The purpose of this study was to evaluate the viability of transplanted mesenchymal stem cells (MSCs) at an early time point (24 hours) based on the type and form of the scaffold used, including type I collagen membrane and synthetic bone. Methods: The stem cells were obtained from the periosteum of the otherwise healthy dental patients. Four symmetrical circular defects measuring 6 mm in diameter were made in New Zealand white rabbits using a trephine drill. The defects were grafted with 1) synthetic bone (${\beta}$-tricalcium phosphate/hydroxyapatite [${\beta}-TCP/HA$]) and $1{\times}10^5MSCs$, 2) collagen membrane and $1{\times}10^5MSCs$, 3) ${\beta}-TCP/HA+collagen$ membrane and $1{\times}10^5MSCs$, or 4) ${\beta}-TCP/HA$, a chipped collagen membrane and $1{\times}10^5MSCs$. Cellular viability and the cell migration rate were analyzed. Results: Cells were easily separated from the collagen membrane, but not from synthetic bone. The number of stem cells attached to synthetic bone in groups 1, 3, and 4 seemed to be similar. Cellular viability in group 2 was significantly higher than in the other groups (P<0.05). The cell migration rate was highest in group 2, but this difference was not statistically significant (P>0.05). Conclusions: This study showed that stem cells can be applied when a membrane is used as a scaffold under no or minimal pressure. When space maintenance is needed, stem cells can be loaded onto synthetic bone with a chipped membrane to enhance the survival rate.

• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.263-270
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• 2002

The Pacific oysters, Crassostrea gigas, were stressed with different concentrations of benzo(a) pyrene and depurated to determine the hemocyte lysosomal membrane stability and hydrolytic enzymatic activity as a biomarker candidate to the chemical, using NRR (neutral red retention) and API ZYM System, respectively. The membrane damage measured as NRR decrease was significant with the increase of chemical concentration and exposure time (P<0.05), providing a possible tool for biomarker. Interestingly, the control showed intrinsic stress probably due to captive life in the laboratory, and a recovering trend was also found during the depuration. The benzo(a)pyrene-exposed oysters showed increased enzyme activities in alkaline phosphatase, esterase (C4), acid phosphatase, naphthol-AS-BI-phospho­hydrolase, $\beta$-galactosidase, $\beta$-glucuronidase, and N-acetyl- $\beta$-glucosaminidase. Of them, only two enzymes, acid phosphatase and alkaline phosphatase, showed some potential available for the generation of enzymatic biomarker in the oyster. The results are suggestive of the potential availability of the cellular and enzymatic properties as a biomarker. However, considering that a robust biomarker should be insensitive to natural stress coming from normal physiological variation, but sensitive to pollutants, a concept of intrinsic stress the animal possesses should be taken into consideration. This reflects the necessity of further research on the intrinsic stress affecting the cellular and enzymatic properties of the chemical­stressed oysters prior to using the data as a biomarker.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.289-294
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• 2002

Cellulose production by Acetobacter pasteurianus was investigated in static culture using four bioreactors with silicone rubber membrane submerged in the medium. The shape of the membrane was flat sheet, flat sack, tube and cylindrical balloon. Production rate of cellulose as well as its yield on consumed glucose by the bacteria grown on the flat type membranes was approximately ten-fold greater than those on the non-flat ones in spite of the same membrane thickness. The membrane reactor using flat sacks of silicone rubber membrane as support of bacterial pellicle can supply greater ratio of surface to volume than a conventional liquid surface culture and is promising for industrial production of bacterial cellulose in large scale.

• Membrane Journal
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• v.2 no.2
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• pp.91-103
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• 1992

Synthetic membrane processes are being increasingly integrated into existing reaction, isolation, and recovery schemes for the production of valuable biological molecules. In many cases they are replacing traditional unit processes. The properties of membrane systems which are most often exploited for both upstream and downstream processing and their permselectivity, high surface area per unit volume, are their potential for controlling the level of contact and/or mixing between two separate phases. Advances in both membrane materials and module design and operation have led to better control of concentration polarization and membrane fouling. After presenting some recent advances in membrane materials and fluid mechanics, we demonstrate how membranes have been integrated into cellular and enzymatic reaction schemes. This is followed by a review of established and emerging synergism between biological processes and synthetic membranes.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.49-55
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• 2018

In this study, we investigated the cellular protective effects and mechanisms of nicotiflorin and its aglycone kaempferol isolated from Annona muricata. The protective effect of these components against $^1O_2$-induced cell damage was also studied by using L-ascorbic acid and (+)-${\alpha}$-tocopherol as controls. Kaempferol exhibited the most potent protective effect, followed by (+)-${\alpha}$-tocopherol and nicotiflorin. L-Ascorbic acid did not exhibit any cellular protective effects. To elucidate the mechanism underlying protective effects, the quenching rate constant of the singlet oxygen, free radical-scavenging activity, ROS-scavenging activity, and uptake ratio of the erythrocyte membrane were measured. The results showed that the cell membrane penetration is a key factor determining the cellular protective effect of kaempferol and its glycoside nicotiflorin. The result from L-ascorbic acid demonstrated that the cellular protective effect of a compound depends on its ability to penetrate the cell membrane and is independent of its antioxidant capacity. In addition, it is suggested that cellular protective effects of kaempferol and (+)-${\alpha}$-tocopherol depend not only on the cell permeability, but also on free radical- and ROS-scavenging activities. These results indicate that the cell permeability and free radical- and ROS- scavenging activities of antioxidants are major factors affecting the protection of cell membranes against the oxidative damage induced by photosensitization reaction.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.143-150
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• 1996

The membrane fatty acid composition of tumor cell can be modified either in cell by altering the lipid composition of the medium of during growth in animals by changing the dietaty fat composition. These modifications are associated with changes in membrane physical properties and certain cellular functions, including carrier-mediated transport and enzyme contained within the membrane. Such effects influence the transport of nutrients and chemotherapeutic agents in cancer cells .Fatty acid modification also can enhance the sensitivity of the neoplastic cell to chemotherapy. The alteration in plasma membrane composition will be affected through dietary supplementations and the potential value to cancer patients could be a better understanding of the effects of diet on responsiveness of neoplasms to chemotherapy, i.e. cancer patients' chances for a "cure" can be improved by diet changes prior to treatment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.4
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• pp.274-279
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• 2002

The purpose of this study is to evaluate the critical maintenance period of absorbable membrane for guided bone regeneration. Fortynine Sprague-Dawley rats weighing about 300g were divided into seven groups. An 8 mm circular full-thickness defect in calvarial bone was made and then cellular acetate porous filter (Millipore $filter^{(R)}$.) was placed on the calvarial bone defect. The filter was removed at 2, 3, 4, 5, 6, 8 and 11 weeks after placement. Rats were sacrificed at 12 weeks the placement of cellular acetate porous filter. The specimens were stained with Hematoxylin-Eosin and observed under light microscope. The amount of regenerated bone was measured from both margin of calvarial bone defect (unit : mm). The results were as follows. Bone regeneration of each experimental group was increased gradually and the bond defect was almost completely filled with new bone in 5-, 6-, 8-, and 11-week experimental group. Histologic findings showed mild inflammatory response and granulation tissue formation without apparent adverse effects on the healing process. In 11-week experimental group, the bone defect was completely filled with new bone containing abundant osteoid which was oriented to the dural side and contribute to bony thickening. We suggest that non-absorbable membrane and bioabsorbable membrane presumably should remain intact for longer than 5 weeks to be effective.

• BMB Reports
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• v.52 no.10
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• pp.601-606
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• 2019

Arginine methylation plays crucial roles in many cellular functions including signal transduction, RNA transcription, and regulation of gene expression. Protein arginine methyltransferase 8 (PRMT8), a unique brain-specific protein, is localized to the plasma membrane. However, the detailed molecular mechanisms underlying PRMT8 plasma membrane targeting remain unclear. Here, we demonstrate that the N-terminal 20 amino acids of PRMT8 are sufficient for plasma membrane localization and that oligomerization enhances membrane localization. The basic amino acids, combined with myristoylation within the N-terminal 20 amino acids of PRMT8, are critical for plasma membrane targeting. We also found that substituting Gly-2 with Ala [PRMT8(G2A)] or Cys-9 with Ser [PRMT8(C9S)] induces the formation of punctate structures in the cytosol or patch-like plasma membrane localization, respectively. Impairment of PRMT8 oligomerization/dimerization by C-terminal deletion induces PRMT8 mis-localization to the mitochondria, prevents the formation of punctate structures by PRMT8(G2A), and inhibits PRMT8(C9S) patch-like plasma membrane localization. Overall, these results suggest that oligomerization/dimerization plays several roles in inducing the efficient and specific plasma membrane localization of PRMT8.

• The Korean Journal of Cytopathology
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• v.12 no.1
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• pp.31-37
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• 2001

Whlie cytologic characteristics of squamous dysplasia, carcinoma in situ, and invasive squamous cell carcinoma of the uterine cervix are well documented, relatively few studios have dealt with the cellular features of microinvasive carcinoma. In order to describe the cellular characteristics of microinvasive squamous cell carcinoma, we retrospectively reviewed 45 cervovaginal smears(15 carcinoma in situ, 15 microinvasive cancer, 15 invasive cancer) which were confirmed by histologic examination of specimens obtained by hysterectomy at the Seoul National University Hospital during S years from 1995 to 1999. The cytologic features about tumor diathesis, inflammatory background, ceil arrangement, anisonucleosis, nuclear membrane irregularity, nuclear chromatin pattern, and nucleoli were observed. The cytologlc characteristics of microinvasive squamous cell carcinoma of the uterine cervix are syncytial pattern, mild tumor diathesis, the irregularity of nuclear membrane, irregularly distributed nuclear chromatin, and occurrence of micronucleoli. But, correlation between the depth of Invasion and the cytologic feature had limited value.