• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.30-40
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• 1981

The moisture sorption and desorption isotherms of various tobaccos were obtained over a relative humidity range from 0 to 90% at $20^{\circ}C$ and $30^{\circ}C$. The hysteresis effect, constant and rate of moisture sorption and desorption, monomolecular-layer moisture content, and specific surface area were analyzed from the obtained data. The moisture sorption and desorption isotherms showed a different characteristics for different tobacco varieties. At a lower humidity range below 50% RH, Burley tobacco had higher moisture sorption and desorption figures than Hicks and Basma, while, at a higher humidity range above 50% RH, Hicks had higher values than the others. The hysteresis effect of tobacco were greater in an intermediate humidity range (40-70% RN), and Basma showed a greater effect than the others. The sorption and desorption constant (K) increased with temperature, but decreased with RH, and Burley tobacco had larger K values, while Hicks had smaller K values than others. The sorption and desorption rate of Burley tobacco were greater than the other tobaccos. The monomolecular-layer moisture was 27.8 and 51.4mg/g, and the specific surface was 101 and $186m^2/g$, for Basma and Burley, respectively.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.1920-1926
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• 2008

We investigated the C-H bond activation mechanism of aldimine by the [RhCl$(PPH_3)_3$] model catalyst using DFT B3LYP//SBKJC/6-31G*/6-31G on GAMESS. Due to their potential utility in organic synthesis, C-H bond activation is one of the most active research fields in organic and organometallic chemistry. C-H bond activation by a transition metal catalyst can be classified into two types of mechanisms: direct C-H bond cleavage by the metal catalyst or a multi-step mechanism via a tetrahedral transition state. There are three structural isomers of [RhCl$(PH_3)_2$] coordinated aldimine that differ in the position of chloride with respect to the molecular plane. By comparing activation energies of the overall reaction pathways that the three isomeric structures follow in each mechanism, we found that the C-H bond activation of aldimine by the [RhCl$(PH_3)_3$] catalyst occurs through the tetrahedral intermediate.

• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.2
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• pp.74-81
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• 2019

Freeze-dried 3^rd day of 5^th instar silkworm powder (FDSP) has been produced and consumed as functional food ingredient in Korea. Generally, FDSP is distributed in the dehumidification state. In this study, the effect of humid condition (30%, 50%, 70%, and 90% RH) on the quality characteristics of FDSP was examined. The color of FDSP, greenish yellow, becomes dark with the change of redness and yellowness. When FDSP is exposed for 4 h at 90% RH, the lightness was changed from 56 to 51, redness from -0.8 to 3.7, and yellowness from 26.5 to 21.6. The proximate composition of FDSP was not significantly changed except 90% RH condition. At that condition, moisture content (5.7%) was increased to 26.8% and crude fat (11.3%) decreased to 1.9% (3 wk 90% RH). Mineral content change during storage can be classified to 3 types; sulfur rapidly decreased, potassium mostly stable with some decreased with humidity, and sodium increased with high humid condition. Vitamins were not significantly affected. However, DNJ was abruptly decreased to 0.03 g/100g in humid condition.

• Korean Journal of Pharmacognosy
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• v.40 no.3
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• pp.238-243
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• 2009

We examined ethanol extracts prepared from 23 Korean local plants obtained in Pyeongchang, Gangwon-do for their inhibitory effects on recombinant human AKR 1 B10 (rhAKR1B10) in vitro. To do this, rhAKR1B10 was first expressed in E. coli as a biological active form and purified by using Ni-affinity chromatography followed by gel permeation chromatography. Then, rhAKR1B10 was used for screening out 23 Korean local plant extracts having an inhibitory activity against itself. Among them, six extracts showed more than 50% inhibition of rhAKR1B10 activity at the concentration of $10{\mu}g$/ml. Especially, the extracts of Ligularia fischeri var. spiciformis Nakai and Rhus trichocarpa Miq. were the most potent because their $IC_{50}$ values were 2.94 and $2.00{\mu}g$/ml, respectively.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.233-239
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• 2017

Background: Nephrotoxicity is the major side effect in cisplatin chemotherapy. Previously, we reported that the ginsenosides Rk3 and Rh4 reduced cisplatin toxicity on porcine renal proximal epithelial tubular cells (LLC-PK1). Here, we aimed to evaluate the protective effect of ginsenosides Rk3 and Rh4 on kidney function and elucidate their antioxidant effect using in vitro and in vivo models of cisplatin-induced acute renal failure. Methods: An enriched mixture of ginsenosides Rk3 and Rh4 (KG-KH; 49.3% and 43.1%, respectively) was purified from sun ginseng (heat processed Panax ginseng). Cytotoxicity was induced by treatment of $20{\mu}M$ cisplatin to LLC-PK1 cells and rat model of acute renal failure was generated by single intraperitoneal injection of 5 mg/kg cisplatin. Protective effects were assessed by determining cell viability, reactive oxygen species generation, blood urea nitrogen, serum creatinine, antioxidant enzyme activity, and histopathological examination. Results: The in vitro assay demonstrated that KG-KH ($50{\mu}g/mL$) significantly increased cell viability (4.6-fold), superoxide dismutase activity (2.8-fold), and glutathione reductase activity (1.5-fold), but reduced reactive oxygen species generation (56%) compared to cisplatin control cells. KG-KH (6 mg/kg, per os) also significantly inhibited renal edema (87% kidney index) and dysfunction (71.4% blood urea nitrogen, 67.4% creatinine) compared to cisplatin control rats. Of note, KG-KH significantly recovered the kidney levels of catalase (1.2-fold) and superoxide dismutase (1.5-fold). Conclusion: Considering the oxidative injury as an early trigger of cisplatin nephrotoxicity, our findings suggest that ginsenosides Rk3 and Rh4 protect the kidney from cisplatin-induced oxidative injury and help to recover renal function by restoring intrinsic antioxidant defenses.

• Korean Journal of Animal Reproduction
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• v.27 no.4
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• pp.299-307
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• 2003

The effects of additions/deletions in glycosylated residues of recombinant human EPO (rhEPO) produced in CHO-K1 on their secretion were examined. hEPO cDNA was amplified from human liver mRNA and cloned into the pCR2.1 TOPO. Using overlapping-extension site-directed mutagenesis method, glycosylation sites at 24th, 38th, 83rd, and 126th were respectively or accumulatively removed by substituting its asparagine (or serine) with glutamine. To add novel glycosylation sites, 69 and 105th leucine was mutated to asparagine. Mutant and wild type rhEPO constructs were cloned into the pcDNA3 expression vector with CMV promoter and transfected into CHO cell line, CHO-K1, to produce mutant rhEPO mutant rhEPO proteins. Enzyme-linked immunosorbant assay (ELISA) and Western analysis with monoclonal anti-EPO antibody were performed using supernatants of the cultures showing transient and stable expressions respectively. Addition of novel glycosylation reduced rhEPO secretion dramatically while deletion mutants had little effect except some double deletion mutants ($\Delta$24/83 and $\Delta$38/83) and triple mutant ($\Delta$24/38/83). This fact suggests that not single but combination of changes in glycosyl groups affect secretion of rhEPO in cell culture, possibly via changes in their conformations.

• KSBB Journal
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• v.21 no.3
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• pp.204-211
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• 2006

For the production of the recombinant human interferon-gamma(rhIFN-${\gamma}$) in Escherichia coli, human glucagon and ferritin heavy chain were used as fusion partners. Even though rhIFN-${\gamma}$ is expressed as an inclusion body form in E. coli because of strong hydrophobicity of itself, over 50% of fused rhIFN-${\gamma}$ was expressed as soluble form in E. coli $Origami^{TM}$(DE3) harboring pT7FH(HE)-IFN-${\gamma}$ which encodes ferritin heavy chain-fused rhIFN-${\gamma}$. In the case of using glucagon-ferritin heavy chain hybrid mutant as a fusion partner, 6X His-tag was additionally introduced to N-terminus of GFHM(HE)-IFN-${\gamma}$ for enhancing purification yields of rhIFN-${\gamma}$. Fusion protein HGFHM(HE)-IFN-${\gamma}$ with two 6X His-tag was more effectively bound to Ni-NTA agarose bead than GFHM(HE)-IFN-${\gamma}$ with a 6X His-tag. rhIFN-${\gamma}$ was completely purified from enterokinase-treated HGFHM(HE)-IFN-${\gamma}$ by Ni-NTA affinity column. For high-level production of rhIFN-${\gamma}$, glucose was used as the sole carbon source with simple exponential feeding rate($2.4{\sim}7.2g/h$) in fed-batch process. The effective lactose concentration for the expression of the rhIFN-${\gamma}$ was $10{\sim}20mM$. Under the fed-batch culture conditions, rhIFN-${\gamma}$ production yield reached 11 g DCW/L for 6 hours after lactose induction.

• Development and Reproduction
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• v.10 no.3
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• pp.159-168
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• 2006

Rodents and many other mammals have two chemosensory systems that mediate responses to pheromones, the main and accessory olfactory system, MOS and AOS, respectively. The chemosensory neurons associated with the MOS are located in the main olfactory epithelium, while those associated with the AOS are located in the vomeronasal organ(VNO). Pheromonal odorants access the lumen of the VNO via canals in the roof of the mouth, and are largely thought to be nonvolatile. The main pheromone receptor proteins consist of two superfamilies, V1Rs and V2Rs, that are structurally distinct and unrelated to the olfactory receptors expressed in the main olfactory epithelium. These two type of receptors are seven transmembrane domain G-protein coupled proteins(V1R with $G_{{\alpha}i2}$, V2R with $G_{0\;{\alpha}}$). V2Rs are co-expressed with nonclassical MHC Ib genes(M10 and other 8 M1 family proteins). Other important molecular component of VNO neuron is a TrpC2, a cation channel protein of transient receptor potential(TRP) family and thought to have a crucial role in signal transduction. There are four types of pheromones in mammalian chemical communication - primers, signalers, modulators and releasers. Responses to these chemosignals can vary substantially within and between individuals. This variability can stem from the modulating effects of steroid hormones and/or non-steroid factors such as neurotransmitters on olfactory processing. Such modulation frequently augments or facilitates the effects that prevailing social and environmental conditions have on the reproductive axis. The best example is the pregnancy block effect(Bruce effect), caused by testosterone-dependent major urinary proteins(MUPs) in male mouse urine. Intriguingly, mouse GnRH neurons receive pheromone signals from both odor and pheromone relays in the brain and may also receive common odor signals. Though it is quite controversial, recent studies reveal a complex interplay between reproduction and other functions in which GnRH neurons appear to integrate information from multiple sources and modulate a variety of brain functions.

• Biomolecules & Therapeutics
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• v.2 no.3
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• pp.270-280
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• 1994

This study was conducted to evaluate the repeated dose toxicity of DA-3030, a recombinant human granulocyte colony stimulating factor(rhG-CSF), in rats. DA-3030 was administered intravenously once a day for 4 weeks to 20 males and 20 females per group at doses of 0(control), 115 and 1150 $\mu\textrm{g}$/kg, and to 15 males and 15 females per group at doses of 1.15 and 11.5$\mu\textrm{g}$/kg. After the administration period, 5 males and 5 females per group in the 0,115 and 1150 $\mu\textrm{g}$/kg groups were placed on withdrawal for 2 weeks. Through-out the study, all the rats survived. The administration of DA-3030 induced, a marked increase in the number of peripheral neutrophils, elevation of serum alkaline phosphatase activity, and splenomegaly in the rats of both sexes receiving 115 or 1150 $\mu\textrm{g}$/kg. Histopathologic examination revealed extramedullary granulopoiesis in spleen and liver, and increase in the number of activated macrophages in spleen in rats of both sexes in 115 and 115 $\mu\textrm{g}$/kg groups, and increased M/E ratio in 11.5, 115 and 1150$\mu\textrm{g}$/kg groups. Most of the changes produced by DA-3030 were thought to be attributable to exaggerated pharmacological effect of the drug, and subsided or disappeared after the recovery period. Under the present condition, no effect dose of DA-3030 is estimated at 1.15 $\mu\textrm{g}$/kg/day.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.5
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• pp.475-485
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• 2017

The present study aimed to explore the neuroprotective effect and possible mechanisms of rhGLP-1 (7-36) against transient ischemia/reperfusion injuries induced by middle cerebral artery occlusion (MCAO) in type 2 diabetic rats. First, diabetic rats were established by a combination of a high-fat diet and low-dose streptozotocin (STZ) (30 mg/kg, intraperitoneally). Second, they were subjected to MCAO for 2 h, then treated with rhGLP-1 (7-36) (10, 20, $40{\mu}g/kg$ i.p.) at the same time of reperfusion. In the following 3 days, they were injected with rhGLP-1 (7-36) at the same dose and route for three times each day. After 72 h, hypoglycemic effects were assessed by blood glucose changes, and neuroprotective effects were evaluated by neurological deficits, infarct volume and histomorphology. Mechanisms were investigated by detecting the distribution and expression of the nuclear factor erythroid-derived factor 2 related factor 2 (Nrf2) in ischemic brain tissue, the levels of phospho-PI3 kinase (PI3K)/PI3K ratio and heme-oxygenase-1 (HO-l), as well as the activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA). Our results showed that rhGLP-1 (7-36) significantly reduced blood glucose and infarction volume, alleviated neurological deficits, enhanced the density of surviving neurons and vascular proliferation. The nuclear positive cells ratio and expression of Nrf2, the levels of P-PI3K/PI3K ratio and HO-l increased, the activities of SOD increased and the contents of MDA decreased. The current results indicated the protective effect of rhGLP-1 (7-36) in diabetic rats following MCAO/R that may be concerned with reducing blood glucose, up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD.