• The Korean Journal of Pharmacology
• /
• v.26 no.1
• /
• pp.1-6
• /
• 1990

We established an in vitro system of central serotonergic neurons by culturing dissociated rat embryonic (El4) brainstem cells to 14 days in vitro and monitored the serotonergic neuronal growth by measuring 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) contents in the cells with hish performance liquid chromatography with electrochemical detection (HPLC-EC). We studied also tile effects of various drugs on the contents of 5-HT and 5-HIAA, confirming in vivo reports. The 5-HT content (13 ng/mg protein) and 5-HT turnover rate (17 pmol/mg protein/h) at 14 days in vitro were in good agreement with those reported in the adult rat brain. The 5-HT content was more easily depleted with p-chlorophenylalanine, a tryptophan hydroxylase inhibitor than with NSD 1015 (3-hydroxybenzylhydrazine), an aromatic L-amino acid decarboxylase (AADC) inhibitor. Incubation of the cultures with tryptophan or 5-hydroxytryptophan increased the rate of serotonin formation implying that neither tryptophan hydroxylase nor AADC is saturated with its amino acid substrate in this in vitro system . The 5-HT content was depleted by reserpine. The 5-HT and 5-HIAA contents were increased and decreased, respectively, by monoamine oxidase inhibitors. All the above results indicate that the biochemical properties of the central serotonergic neurons in this culture system reflect reliably those of central serotonergic neurons in vivo. We suggest that measuring 5-HT and 5-HIAA contents in the primary cultured dissociated brainstem-cells with HPLC-EC is useful in the study of pharmacology as well as toxicolgy of the central serotonergic neurons.

• Journal of Nutrition and Health
• /
• v.14 no.2
• /
• pp.97-104
• /
• 1981

In order to study the changes of components and enzyme activities during Chungkookjang-Koji preparation, the Kojies were prepared with Bacillus Natto, Bacillus subtilis and traditional method. The temperature of Koji materials during Koji preparation was very different according to the experimental group. The content of ethyl alcohol, reducing sugar, amino nitrogen and water soluble nitrogen were changed by the Koji preparing stage and experimental group. Amylase and protease activities showed on irregular change on standing and their activities were not remarkably different among the groups and appeared weakly.

• The Journal of Korean Academy of Prosthodontics
• /
• v.55 no.4
• /
• pp.381-388
• /
• 2017

Purpose: Unpredictable shrinkage of zirconia during sintering process causes discrepancy. Therefore, there have been attempts to reduce discrepancy by milling zirconia after sintering. However, due to the hardness of sintered zirconia, milling takes longer time, causes damage to the machine and causes chip formation. With customized zirconia block using the mean dimension of prepared natural dentition, it is expected to overcome these shortcomings. Materials and methods: The mean dimension of prepared natural dentition was analyzed as STL file after scanning of prepared teeth treated at SNUDH. The transverse, frontal and sagittal planes were set using Mimics and Photoshop. 3D volume was projected on each plane, and the outer line was measured through external tangent line, and the inner line was measured through inflection point of tangent line. Results: The mean height of prepared incisal (N = 57) is $6.60{\pm}1.05mm$, mesiodistal length is $2.98{\pm}0.73mm$, buccolingual length is $2.04{\pm}0.73mm$. The mean height of prepared premolar (N = 15) is $5.37{\pm}1.49mm$, mesiodistal length is $4.10{\pm}1.78mm$, buccolingual length is $5.86{\pm}1.55mm$. And the mean height of prepared molar (N = 13) is $5.11{\pm}1.29mm$, mesiodistal length is $6.80{\pm}1.18mm$, buccolingual length is $7.34{\pm}1.40mm$. Conclusion: Using the mean dimension of prepared natural dentition, it is expected to be able to fabricate customized zirconia block.

• The Journal of Korean Academy of Prosthodontics
• /
• v.53 no.2
• /
• pp.120-127
• /
• 2015

Purpose: The aim was to investigate the effect of implant thread designs on the stress dissipation of the implant. Materials and methods: The threads evaluated in this study included the V-shaped, buttress, reverse buttress, and square-shaped threads, which were of the same size (depth). Building four different implant/bone complexes each consisting of an implant with one of the 4 different threads on its cylindrical body ($4.1mm{\times}10mm$), a force of 100 N was applied onto the top of implant abutment at $30^{\circ}$ with the implant axis. In order to simulate different osseointegration stages at the implant/bone interfaces, a nonlinear contact condition was used to simulate immature osseointegration and a bonding condition for mature osseointegration states. Results: Stress distribution pattern around the implant differed depending on the osseointegration states. Stress levels as well as the differences in the stress between the analysis models (with different threads) were higher in the case of the immature osseointegration state. Both the stress levels and the differences between analysis models became lower at the completely osseointegrated state. Stress dissipation characteristics of the V-shape thread was in the middle of the four threads in both the immature and mature states of osseointegration. These results indicated that implant thread design may have biomechanical impact on the implant bed bone until the osseointegration process has been finished. Conclusion: The stress dissipation characteristics of V-shape thread was in the middle of the four threads in both the immature and mature states of osseointegration.

• Journal of Soil and Groundwater Environment
• /
• v.14 no.6
• /
• pp.65-70
• /
• 2009

Reduction of groundwater surface tension prior to air sparging (SEAS, surfactant-enhanced air sparging) was known to increase air saturation in the aquifer under influence, possibly enhancing the removal rates of volatile contaminants. Although SEAS was known to be efficient for increasing air saturation, little information is available for different hydrogeological settings including soil particle sizes and the depth of aquifer. We investigated water saturations in the sparging influence zone during SEAS using one-dimensional column packed with sands of different particle sizes and different aquifer depths. An anionic surfactant was used to suppress the surface tension of water. Two different sands were used; the air entry pressures of the sands were measured to be $15.0\;cmH_2O$, and $36.3\;cmH_2O$, respectively. No significant difference was observed in the water saturation-surface tension relationship for sands with different particle sizes. As the surface tension decreased, the water saturation decreased to a lowest point and then it increased with further decrease in the surface tension. Both sands reached their lowest water saturations when the surface tension was set approximately at 42 dyne/cm. SEAS was conducted at three different aquifer depths; 41 cm, 81 cm, and 160 cm. Water saturation-surface tension relationship was consistent regardless of the aquifer depth. The size of sparging influence zone during SEAS, measured using two-dimensional model, was found to be similar to the changes in air saturation, measured using one-dimensional model. Considering diverse hydrogeological settings where SEAS to be applied, the results here may provide useful information for designing SEAS process.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.6
• /
• pp.814-821
• /
• 2014

As a natural plant ingredients, glasswort (Salicornia herbacea L.) contains various physiological activities, mainly anti-oxidative and anti-diabetic activities. However, only a few studies have been carried out on its anti-adipogenic effect. This study investigated the anti-obesity effects of Salicornia herbacea L. on 3T3-L1 adipocytes. As adipogenesis of preadipocytes to adipocytes involves proliferation and differentiation of cells, we treated three concentrations (125, 250, and $500{\mu}g/mL$) of Salicornia herbacea L. water extracts (SLW) in both pre-processing and post-processing stages. When 3T3-L1 adipocytes were differentiated and dyed with Oil Red O, adipocytes size and the value of relative Oil Red O staining were reduced by all concentrations of SLW in post-processing stage. Following adipogenic differentiation, the concentration of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in the cell supernatant significantly increased upon treatment with $125{\mu}g/mL$ of SLW and further rose at concentrations of 250 and $500{\mu}g/mL$ during post-processing stage. There was no significant difference in glycerol production upon SLW treatment. Leptin production significantly decreased at all SLW concentrations during post-processing stage, whereas peroxisome proliferator activated receptor-${\gamma}$ (PPAR-${\gamma}$) and adiponectin secretions were significantly enhanced. Overall results showed that SLW might have an anti-adipogenic effect via enhancement of TNF-${\alpha}$ production, which causes dedifferentiation and inhibits lipid accumulations in adipocyte. Furthermore, SLW might prevent diabetes and cardiovascular disease, as it reduces leptin secretion and enhances production of both PPAR-${\gamma}$ and adiponectin. However, further research is needed to elucidate the exact mechanism and bioactive compounds of glasswort.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.6
• /
• pp.783-788
• /
• 2016

Excessive intake of trans fats is a risk factor for cardiovascular diseases. Previously, we showed that green tea extract lowers intestinal absorption of cholesterol and elaidic acid in rats. This study was conducted to investigate a possible role for sorghum extract on lymphatic absorption of trans fat and cholesterol in rats. Adult male rats with lymph cannulae were infused at a rate of 3.0 mL/h for 8 h via a duodenal catheter with a lipid emulsion containing $146.4{\mu}mol$ of trielaidin, $36.8{\mu}mol$ of trilinoelaidin, $452.0{\mu}mol$ of triolein, $1.0{\mu}Ci$ cholesterol labeled with $^{14}C$ ($^{14}C-cholesterol$), $20.7{\mu}mol$ of cholesterol, and $396.0{\mu}mol$ of Na-taurocholate without or with 100.0 mg of sorghum extract in phosphate-buffered saline buffer (pH 6.4). Lymph was collected hourly for 8 h. No significant difference was noted in lymph flow. However, the lymphatic absorption of elaidic acid and linoelaidic acid for 8 h was significantly lower in rats infused with sorghum extract than in those infused with no sorghum extract. Further, lymphatic absorption of $^{14}C-cholesterol$ was reduced by sorghum extract, which was observed previously. These data indicate that sorghum extract has an inhibitory effect on the intestinal absorption of trans fat and cholesterol. The mechanism(s) by which sorghum extract lowers intestinal absorption of trans fat warrants further study.

• Korean Journal of Microbiology
• /
• v.48 no.4
• /
• pp.314-318
• /
• 2012

Most types of collagen used for biomedical applications, such as cell therapy and tissue engineering, are derived from animal tissues. Therefore, special precautions must be taken during the production of these proteins in order to assure against the possibility of the products transmitting infectious diseases to the recipients. The ability to remove and/or inactivate known and potential viral contaminants during the manufacturing process is an ever-increasingly important parameter in assessing the safety of biomedical products. The purpose of this study was to evaluate the efficacies of the 70% ethanol treatment and pepsin treatment at pH 2.0 for the inactivation of bovine viruses during the manufacture of collagen type I from bovine hides. A variety of experimental model viruses for bovine viruses including bovine herpes virus (BHV), bovine viral diarrhea virus (BVDV), bovine parainfluenza 3 virus (BPIV-3), and bovine parvovirus (BPV), were chosen for the evaluation of viral inactivation efficacy. BHV, BVDV, BPIV-3, and BPV were effectively inactivated to undetectable levels within 1 h of 70% ethanol treatment for 24 h, with log reduction factors of ${\geq}5.58$, ${\geq}5.32$, ${\geq}5.11$, and ${\geq}3.42$, respectively. BHV, BVDV, BPIV-3, and BPV were also effectively inactivated to undetectable levels within 5 days of pepsin treatment for 14 days, with the log reduction factors of ${\geq}7.08$, ${\geq}6.60$, ${\geq}5.60$, and ${\geq}3.59$, respectively. The cumulative virus reduction factors of BHV, BVDV, BPIV-3, and BPV were ${\geq}12.66$, ${\geq}11.92$, ${\geq}10.71$, and ${\geq}7.01$. These results indicate that the production process for collagen type I from bovine hides has a sufficient virus-reducing capacity to achieve a high margin of virus safety.

• Journal of Distribution Research
• /
• v.13 no.2
• /
• pp.29-57
• /
• 2008

Empirical model was developed to test the building mechanism of trust dimensions and loyalty with the suppliers' bonding tactics to service firms. And interactive effects between suppliers' bonding tactics and service firms' store age was hypothesized in the trust-loyalty building processes. The model was tested in the context of animal clinics which belong to Korean Animal Hospital Association (KAHA). The data was analysed using structural equation model (SEM). The findings are as follows. First, two different relational bonding tactics play different roles in their effects on building trust dimensions toward suppliers. While supplier's social bonding tactic significantly influences on both the affective and cognitive trust of service firms, suppliers' structural bonding tactic only influences significantly on affective trust of service firms. Second, while suppliers' social bonding tactic influences on building service firms' loyalty significantly, suppliers' structural bonding tactic doesn't influence on building their loyalty. Suppliers' structural bonding tactic influences on building their loyalty indirectly through affective trust. Third, while service firms' affective trust influences on building loyalty significantly, cognitive trust doesn't. Their cognitive trust influences on building loyalty indirectly through affective trust. Fourth, the higher the firms' store age is, the more suppliers use social bonding tactics to build trust and loyalty directly. While the shorter the firms' store age is, the more suppliers partially use both the social and structural bonding tactics to build trust and loyalty. In conclusion, in the context of animal clinics' distribution channels, suppliers' relational bonding tactics with service firms differently influence to build trust sub-dimensions and loyalty. And, suppliers should take note of the interactive role of service firms' store age in the utilization of the different bonding tactics to build service firms' trust and loyalty toward suppliers. At the end of the paper, managerial implications, limitations, and future research directions are suggested.

• The Korean Journal of Pharmacology
• /
• v.32 no.1
• /
• pp.13-21
• /
• 1996

Intracellular calcium concentration ($[Ca^{2+}]_i$) may play a crucial role in a variety of neuronal functions. Here we report that in primary culture of mouse cerebellar granule cells nicotinic acetylcholine receptors (nAChRs) are expressed in a specific developmental stage and involved in the regulation of intracellular calcium homeostasis. Nicotine-mediated calcium responses were measured using $^{45}Ca^{2+}$ or fluorometrically using the calcium-sensitive fluorescent dye fura-2. Maximal uptake of $^{45}Ca^{2+}$ evoked by nicotine in mouse cerebellar granule cells were revealed $8{\sim}12$ days in culture. In contrast, nicotine did not alter the basal $^{45}Ca^{2+}$ uptake in cultured glial cells. In cerebellar granule cells nicotine-evoked $^{45}Ca^{2+}$ uptake was largely blocked by the NMDA receptor antagonists. Glutamate pyruvate transaminase (GPT). which removes endogenous glutamate, also prevented nicotine effects, implying the indirect involvement of glutamate in nicotine-mediated calcium responses. Fluorometric studies using fura-2 showed two phases of nicotine-evoked $[Ca^{2+}]_i$ rises: the initial rising phase and the later plateau phase. Interestingly, the NMDA receptor antagonists and GPT appeared to inhibit only the later plateau phase of nicotine-evoked $[Ca^{2+}]_i$ rises. The present results imply that nicotine mediated $^{45}Ca^{2+}$ uptake and $[Ca^{2+}]_i$ rises are attributed to the calcium fluxes through both nAchRs and NMDA receptors in a time-dependent manner. Consequently, nAChRs may play an important role in neuronal development by being expressed in a specific developmental stage and regulating the intracellular calcium homeostasis.