• Journal of Hydrogen and New Energy
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• v.21 no.1
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• pp.12-18
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• 2010

Photobiological hydrogen production using Rhodobacter sphaeroides KD131 was studied on the effect of light intensities and nitrogen sources. Media containing malate and glutamate were shown higher hydrogen production rate than that containing succinate and $(NH_4)_2SO_4$ at the $110\;W/m^2$ illumination by halogen lamp at $30^{\circ}C$. Media lacking glutamate as the nitrogen source exhibited higher hydrogen production than that containing glutamate. Initial cell concentration was optimized to 1.0 at the absorbance of 660 nm. Hydrogen production was increased by increasing the light intensity from 0 to $216\;W/m^2$ but the increasing rate declined over $108\;W/m^2$.

• Biomolecules & Therapeutics
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• v.2 no.2
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• pp.131-135
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• 1994

The effect of ginsenoside (GS) from Panax ginseng on basal and nitro-L-arginine suppressed nitric oxide (NO) production was studied in rat kidney. NO production was determined by conversion to [$^{14C}$]=L-citrulline from [$^{14C}$]-L-arginine both in whole kidney and three renal segments; glomerulus, cortex excluding glomerulus (cortex-) and medulla. Nitro-L-arginine (total dose of 30 mg/kg/3 days, i.p.) significantly reduced NO production in whole kidney, which was prevented by GS pretreatment (30 mg/kg/3 days, i.p.). Relative high dose of GS (120 mg/kg/4 days, i.p..) selectively increased NO production in glomerulus and cortex-. Protein content, on wet weight basis, in cortex- and glomerular DNA content were significantly reduced by GS. Our results confirm the existence of constitutive nitric oxide synthase in kidney and it seems that target nephron segment for volume expansion due to GS'NO-mediated vasodilation and for NO production stimulated by GS is cortex including glomerulus.lus.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.51-62
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• 2007

Objective : The aim of this study is to assess the effect of Schizandrae Fructus on melanin synthesis inhibition and whitening effect. Methods : We assessed inhibitory effects of Schizandrae Fructus on melanin-release from B16F10, on melanin production in B16F10, on mushroom tyrosinase activity in vitro, on tyrosinase activity in B16F10 and effect of Schizandrae Fructus on the expression tyrosinase, TRP-1, TRP-2, PKA, ERK-1 ERK-2, AKT-1, MITF in B16F10. Results and Conclusion : 1. Schizandrae Fructus inhibited melanin-release, melanin production in B16F10. 2. Schizandrae Fructus inhibited tyrosinase activity in vitro and in B16F10. 3. Schizandrae Fructus suppressed the expression of tyrosinase, TRP-1, TRP-2, PKA, ERK-2 in B16F10.

• Economic and Environmental Geology
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• v.57 no.2
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• pp.129-141
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• 2024

This study derived production-production multipliers using a regional input-output table and estimated the induced effect of aggregates through the non-metallic minerals sector and the concrete products sector. In deriving the induced effect of aggregates, it is difficult to use the regional input-output table due to the sector classification problem. This study analyzed the non-metallic mineral sector, including aggregates, as aggregates sector, and the concrete products sector, which uses most of the aggregate production. By analyzing this, we attempted to alleviate difficulties caused by sector classification restrictions. In the process of estimating the induced effect, it was assumed that there was a decrease in aggregate production, and in the process of analyzing the concrete products sector, the effect of the decrease in concrete product production due to the decrease in aggregate production, that is, the decrease in production of one unit of aggregate was 0.8511 in the concrete product sector. The analysis was conducted on the premise of a decrease in unit production. Inducing effects within and between regions were calculated for the 17 metropolitan cities and provinces classified by the regional input-output table. The employment effect was also calculated, assuming a 10% production decrease to show differences according to the size of the aggregate and concrete product sectors in each region.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.5
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• pp.397-402
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• 2014

Microglia are activated by inflammatory and pathophysiological stimuli in neurodegenerative diseases, and activated microglia induce neuronal damage by releasing cytotoxic factors like nitric oxide (NO). Activated microglia synthesize a significant amount of vitamin $D_3$ in the rat brain, and vitamin $D_3$ has an inhibitory effect on activated microglia. To investigate the possible role of vitamin $D_3$ as a negative regulator of activated microglia, we examined the effect of 25-hydroxyvitamin $D_3$ on NO production of lipopolysaccharide (LPS)-stimulated microglia. Treatment with LPS increased the production of NO in primary cultured and BV2 microglial cells. Treatment with 25-hydroxyvitamin $D_3$ inhibited the generation of NO in LPS-activated primary microglia and BV2 cells. In addition to NO production, expression of 1-${\alpha}$-hydroxylase and the vitamin D receptor (VDR) was also upregulated in LPS-stimulated primary and BV2 microglia. When BV2 cells were transfected with 1-${\alpha}$-hydroxylase siRNA or VDR siRNA, the inhibitory effect of 25-hydroxyvitamin $D_3$ on activated BV2 cells was suppressed. 25-Hydroxyvitamin $D_3$ also inhibited the increased phosphorylation of p38 seen in LPS-activated BV2 cells, and this inhibition was blocked by VDR siRNA. The present study shows that 25-hydroxyvitamin $D_3$ inhibits NO production in LPS-activated microglia through the mediation of LPS-induced 1-${\alpha}$-hydroxylase. This study also shows that the inhibitory effect of 25-hydroxyvitamin $D_3$ on NO production might be exerted by inhibiting LPS-induced phosphorylation of p38 through the mediation of VDR signaling. These results suggest that vitamin $D_3$ might have an important role in the negative regulation of microglial activation.

• The Journal of Pediatrics of Korean Medicine
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• v.29 no.2
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• pp.26-36
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• 2015

Objectives In this study, effect of Geumsuyukgunjeon (GYJ) on the increase in airway epithelial mucosubstances of rats with acute bronchitis and EGF-induced MUC5AC mucin production from human airway epithelial cells were investigated. Materials and Methods Hypersecretion of airway mucus was induced by exposure of rats to SO2 during 3 weeks. Effect of orally-administered GYJ during 2 weeks on increase in airway epithelial mucosubstances from tracheal goblet cells of rats was assesed using histopathological analysis after staining the epithelial tissue with PAS-alcian blue. Possible cytotoxicity of GYJ was assessed by examining the potential damage of kidney and liver functions by measuring serum GOT/GPT activities and serum BUN and creatinine concentrations of rats and the body weight gain during experiment, after administering GYJ orally. Effect of GYJ on EGF-induced MUC5AC mucin production from human airway epithelial cells (A549) was investigated. Confluent A549 cells were pretreated for 30 min in the presence of GYJ and treated with EGF (25 ng/ml) for 24 hrs, to assess the effect of GYJ on EGF-induced MUC5AC mucin production using enzyme-linked immunosorbent assay (ELISA). Results (1) GYJ decreased the amount of intraepithelial mucosubstances of trachea of rats. (2) GYJ did not show kidney and liver toxicities and did not affect body weight gain of rats during experiment. (3) GYJ significantly inhibited EGF-induced MUC5AC mucin production from A549 cells. Conclusions The result from the present study suggests that GYJ might control both the mucus hypersecretion in vivo and do not show in vivo toxicity to liver and kidney functions after oral administration and the production of pulmonary mucin.

• KSBB Journal
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• v.25 no.2
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• pp.173-178
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• 2010

Antifungal effect of Ginkgo biloba leaves extracts conducted for Pityrosporum ovale. Antifungal effect verified by diffusion test, optical density test and colony counting test under various concentration. Extract of ginkgo biloba leaves performed with 40% ethanol and 60% water solution at $60^{\circ}C$ and major components analyzed by HPLC. The concentrated extract have bilobalide and ginkgolide A and ginkgolide B and their concentration were 153.0 mg/L, 8403.5 mg/L and 2723.0 mg/L respectively. Ginkgo biloba leaves extracts gave 99.1% of antifungal effect for Pityrosporum ovale examined by colony counting method.

• Advances in Traditional Medicine
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• v.6 no.1
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• pp.39-44
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• 2006

Ji-Jang-Soo (JJS) is known to have a detoxification effect. However, it is still unclear how JJS has these effects in experimental models. In this study, we investigated the effect of JJS on the viability of cells and production of cytokines in human T-cell line, MOLT-4 cells, and human mast cell line, HMC-1 cells. The MOLT-4 cells were cultured for 24 h in the presence or absence of JJS. As the result, JJS (1/100 dilution) significantly increased the cell viability about 78% (P < 0.05) and also increased the interleukin (IL)-2, and interferon $(IFN)-{\gamma}$ production compared with media control at 24 h. But had no effect on IL-4 production. Hypoxia mimic compound, desferroxamine (DFX) decreased the immune cell viability. Cell viability decreased by DFX was increased by JJS. In conclusion, these data indicate that JJS may have an immune-enhancing effect.

• Journal of Korea Trade
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• v.25 no.1
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• pp.133-151
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• 2021

Purpose - This study examines the effects of expatriate transfer on foreign affiliate's labor productivity. Design/methodology - Using Korean-owned foreign affiliate-level data, we estimate the effect of expatriate transfer on foreign affiliate's labor productivity using the system generalized method of moments model. We also consider foreign affiliate- and host country-specific contingencies and test how they are associated with expatriates in enhancing foreign affiliate's labor productivity. Findings - We consider foreign production intensity and cultural distance between the home (i.e., South Korea) and host countries as key contingencies that influence the effect of expatriates on foreign affiliate's labor productivity. We find that expatriates are effective in enhancing the labor productivity of less production-intensive foreign affiliates. This effect is strengthened as expatriates are deployed to countries that share cultural similarities with the home country. Originality/value - Considering that previous studies provide mixed results on the effect of expatriates, our findings suggest that foreign affiliate-specific operational orientation and cultural distance should be considered jointly to understand the true effect of expatriate staffing on foreign affiliate performance.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.57-58
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• 2000

Production of dye-decolorizing enzyme was investigated with the cultivation of Geotrichum candidum Dec1 (abbreviated to Dec1) using molasses as a cheap raw materials. Molasses was found to stimulate the enzyme production as well as a role of carbon source, because the production increased with molasses content up to 50 g/L. However, the severe inhibition of dye-decolorizing enzyme activity was observed even at low concentration of molasses 10 g/L when purified decolorizing peroxidase was used. Its inhibitory effect was reduced through the cultivation of Dec1. The fractions of molasses separated by a gel chromatography showed the different degrees of inhibition. As a way to reduce the inhibitory effect, the dilution of culture broth was examined, and the total decolorizing activity for Reactive blue 5 increased 7 times as much as that of original culture broth by 30 times dilution. On the basis of result, we proposed a process scheme which can fully utilize both positive and negative effect of molasses in dye-decolorizing process using molasses.