• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.2
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• pp.61-65
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• 2009

In this paper, we report on the growth and optical characteristics of white-LED without fluorescent material. The growth of DH(double heterostructure) with AlGaN active layer was performed on a n-GaN/(0001) $Al_{2}O_{3}$ by the mixed-source HVPE and multi-sliding boat. The CRI(color rendering index) of packaging device charged in the range 72-93 with CIE chromaticity coordinates(x=$0.26{\sim}0.34$, y=$0.31{\sim}0.40$). And CCT(correlated color temperature) values was measured $5126{\sim}10406K$ with increasing injection current. The CIE point of conventional phosphor white LED shifts blue region, but cm point of non-phosphor white LED shifts opposite direction. These results show the mixed-source HVPE can be possible to newly fabricate method of phosphor free white LED with high CRI value.

• Journal of Life Science
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• v.22 no.6
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• pp.828-836
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• 2012

The objective of the current study was to determine the effects of the extracts isolated from the fruit body of Flammulina velutipes cultivated with oriental herbal plants on mouse splenocytes, B cells, and macrophages in vitro. The ethanol extracts B (EEB) directly induced the proliferation of spleen cells in a dose-dependent manner and increased IL-6, TNF-${\alpha}$, and IFN-${\gamma}$ synthesis. The EEB also increased the proliferation of B cells in a dose-dependent manner. The production of immunoglobulin M, G1, G2a, G2b, and IgG3 in the presence of the EEB increased progressively in the culture supernatant. When the EEB were used in macrophage cell line (RAW264.7) stimulation, there was a marked induction of NO synthesis in a dose-dependent manner and an increased IL-6, TNF-${\alpha}$, and GM-CSF synthesis. Intraperitoneal injection with EBB showed life prolongation effect of 16.1% in mice previously inoculated with sarcoma-180, respectively. These results suggest that the capacity of the EEB isolated from the fruit body of Flammulina velutipes cultivated with oriental herbal plants seems to act as a potent immunomodulator causing augmentation of immune cell activity, and with the absence of notable side-effects, Flammulina velutipes EEB could be used as a biological response modifier having possible therapeutic effects against immunological disorders. This study also showed that functional components of Flammulina velutipes were possibly improved by incorporating oriental herbal plants in a growth medium.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.519-525
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• 2010

Purpose: Of various effects of relaxin, we assumed that anti-fibrotic effects, neovascularization effects and vasodilatation effects of relaxin might enhance the survival rate of skin flap. In the current study, we used adenovirus expressing relaxin genes to examine whether these genes could enhance the survival rate of a skin flap. Methods: A total of 30 Sprangue-Dawley rats were divided into three groups: RLX group (10; relaxin virus injected group), CTR group (10; no gene coded virus injection group), and PBS group (10; PBS injected group). Each group was intradermally injected with the virus ($10^7$ PFU) and PBS 48 hours before and immediately before the flap elevation. A distally based flap $3{\times}9\;cm$ in size was elevated on the dorsal aspect of each rat. Following this, a flap was placed in the original location and then sutured using a #4-0 Nylon. A surviving area of the flap was measured and then compared on postoperative days 3, 7 and 10. Using a laser Doppler, the amount of blood flow was measured. On postoperative day 10, tissues were harvested for histologic examination and the number of blood vessels was counted. Results: There was a significant increase in the area of the flap survival in the RLX group on postoperative days 3 and 7. The Doppler measurement also showed significantly increased blood flow immediately after the operation and on postoperative days 7 and 10. The number of blood vessels was significantly greater in the RLX group in the tissue harvested on postoperative day 10. The VEGF concentration was significantly higher in the RLX group than others in the tissues harvested on postoperative day 10. Conclusion: Following an analysis of the effects of relaxin-secreting adenovirus on the survival of a flap, the surviving area of the flap and the blood flow also increased. A histopathology also showed an increase in the number of blood vessels and the concentration of VEGF.

• Biomolecules & Therapeutics
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• v.5 no.1
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• pp.100-105
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• 1997

DW-166HC ($^{166}$Holmium-chitosan) is a complex of $^{166}$Ho, $\beta$- and $\gamma$-ray emitter, and chitosan, a polymer of glucosamine, with radiotherapeutic potential. The current study was performed to determine the acute toxicities of $^{165}$Ho-chitosan in mice by two different routes of administration. The both sex mice were given a single intravenous bolus injection of $^{165}$Ho-chitosan complex at doses of 12, 10, 6, 5 and 4 mg/kg or subcutaneous administration at doses of 600, 500, 400 and 300 mg/kg. Chitosan was dosed to control animals as 16 and 800 mg/kg, intravenously and subcutaneously, respectively. The doses of $_{165}$Ho-chitosan complex were expressed as $_{165}$holmium nitrate pentahydrate and the ratio of $^{165}$Ho$(NO_3)_3$).$5H_2O$ to chitosan was 3/4 Severe convulsion and respiratory failure were followed by death within 10 min after intravenous dosing. Transient unilateral hindlimb hypokinesias were found in two mice of 5 mg/kg dosing group during the study period. No abnormalities were observed during the necropsy of survived animals in intravenous dosing group. Only one male animal was found dead in 500 mg/kg subcutaneously dosed group. Alopecia with or without cutaneous ulcer were found in most mice including control animals. During necropsy, omental adhesion was observed in all dose ranges and enlarged spleen was found in several animals including control group. It is suggested that the acute intravenous >).$LD_{50}s$ for male and female mice were 4.90 and 6.03 mg/kg, respectively. The lowest lethal dose in male was 500 mg/kg by subcutaneous administration.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.1
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• pp.17-22
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• 2011

Quercetin mainly exists in the skin of colored fruits and vegetables as one of flavonoids. Recent studies show that quercetin, like other flavonoids, has diverse pharmacological actions. However, relatively little is known about quercetin effects in the regulations of ligand-gated ion channels. In the previous reports, we have shown that quercetin regulates subsets of homomeric ligand-gated ion channels such as glycine, 5-$HT_{3A}$ and ${\alpha}7$ nicotinic acetylcholine receptors. In the present study, we examined quercetin effects on heteromeric neuronal ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor channel activity expressed in Xenopus oocytes after injection of cRNA encoding bovine neuronal ${\alpha}3$ and ${\beta}4$ subunits. Treatment with acetylcholine elicited an inward peak current ($I_{ACh}$) in oocytes expressing ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor. Co-treatment with quercetin and acetylcholine inhibited $I_{ACh}$ in oocytes expressing ${\alpha}3{\beta}4$ nicotinic acetylcholine receptors. The inhibition of $I_{ACh}$ by quercetin was reversible and concentration-dependent. The half-inhibitory concentration ($IC_{50}$) of quercetin was $14.9{\pm}0.8\;{\mu}M$ in oocytes expressing ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor. The inhibition of $I_{ACh}$ by quercetin was voltage-independent and non-competitive. These results indicate that quercetin might regulate ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor and this regulation might be one of the pharmacological actions of quercetin in nervous systems.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.265-271
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• 2014

Interleukin-7 (IL-7) is a potent anti-apoptotic cytokine that enhances immune effector cell functions and is essential for lymphocyte survival. While it known to induce differentiation and proliferation in some haematological malignancies, including certain types of leukaemias and lymphomas, little is known about its role in solid tumours, including breast cancer. In the current study, we investigated whether IL-7 could enhance the in vivo antitumor activity of tumor-reactive $CD8^+$ T cells with induction of IFN-${\gamma}$ in a murine breast cancer model. Human IL-7 cDNA was constructed into the eukaryotic expression plasmid pcDNA3.1, and then the recombinational pcDNA3.1-IL-7 was intratumorally injected in the TM40D BALB/C mouse graft model. Serum and intracellular IFN-${\gamma}$ levels were measured by ELISA and flow cytometry, respectively. $CD8^+$ T cell-mediated cytotoxicity was analyzed using the MTT method. Our results showed that IL-7 administration significantly inhibited tumor growth from day 15 after direct intratumoral injection of pcDNA3.1-IL-7. The anti-tumor effect correlated with a marked increase in the level of IFN-${\gamma}$ and breast cancer cells-specific CTL cytotoxicity. In vitro cytotoxicity assays showed that IL-7-treatment could augment cytolytic activity of $CD8^+$ T cells from tumor bearing mice, while anti-IFN-${\gamma}$ blocked the function of $CD8^+$ T cells, suggesting that IFN-${\gamma}$ mediated the cytolytic activity of $CD8^+$ T cells. Furthermore, in vivo neutralization of $CD8^+$ T lymphocytes by CD8 antibodies reversed the antitumor benefit of IL-7. Thus, we demonstrated that IL-7 exerts anti-tumor activity mainly through activating $CD8^+$ T cells and stimulating them to secrete IFN-${\gamma}$ in a murine breast tumor model. Based on these results, our study points to a potential novel way to treat breast cancer and may have important implications for clinical immunotherapy.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.4
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• pp.195-201
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• 2011

The flavonoid quercetin is a low molecular weight compound generally found in apple, gingko, tomato, onion and other red-colored fruits and vegetables. Like other flavonoids, quercetin has diverse pharmacological actions. However, relatively little is known about the influence of quercetin effects in the regulation of ligand-gated ion channels. Previously, we reported that quercetin regulates subsets of nicotinic acetylcholine receptors such as ${\alpha}3{\beta}4$, ${\alpha}7$ and ${\alpha}9{\alpha}10$. Presently, we investigated the effects of quercetin on muscle-type of nicotinic acetylcholine receptor channel activity expressed in Xenopus oocytes after injection of cRNA encoding human fetal or adult muscle-type of nicotinic acetylcholine receptor subunits. Acetylcholine treatment elicited an inward peak current ($I_{ACh}$) in oocytes expressing both muscle-type of nicotinic acetylcholine receptors and co-treatment of quercetin with acetylcholine inhibited $I_{ACh}$. Pre-treatment of quercetin further inhibited $I_{ACh}$ in oocytes expressing adult and fetal muscle-type nicotinic acetylcholine receptors. The inhibition of $I_{ACh}$ by quercetin was reversible and concentration-dependent. The $IC_{50}$ of quercetin was $18.9{\pm}1.2{\mu}M$ in oocytes expressing adult muscle-type nicotinic acetylcholine receptor. The inhibition of $I_{ACh}$ by quercetin was voltage-independent and non-competitive. These results indicate that quercetin might regulate human muscle-type nicotinic acetylcholine receptor channel activity and that quercetin-mediated regulation of muscle-type nicotinic acetylcholine receptor might be coupled to regulation of neuromuscular junction activity.

• Resources Recycling
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• v.27 no.1
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• pp.45-54
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• 2018

This study aimed to investigate the effects of mechanical factors such as agitation speed and air rate in fly ash flotation. Specifically, we used thermal power plant fly ash with unburned carbon content of 3.4 to 3.7%. The effect of pH, agitation speed, collector dosage, and frother dosage - the key factors of froth flotation - showed unburned carbon recovery and unburned carbon content of 63% and 34%, respectively, when the dosage of safflower oil used as collector was 800 g/ton, pH was 7, agitation speed was 1,200 rpm, and frother dosage was 400 g/ton. The SEM/EDS analysis of fly ash in that case indicated that the spherical fly ash particles lowered the unburned carbon content as they floated with the air bubbles without being dissolved in the unburned carbon or settled in the ore solution. The other experiment of changing the mechanical factors such as agitation speed and air rate resulted in unburned carbon recovery and unburned carbon content of 74% and 67%, respectively, at air rate of 8 L/min and agitation speed of 900 rpm. The recovery and unburned carbon content increased as the low agitation speed and additional air injection decreased the strength of the eddy current in the ore solution and consequently prevented the floating of fine fly ash particles with unburned carbon. In addition, the recovery rate and unburned carbon increased further to 80% and 70%, respectively, showing the best performance when the agitation speed and air rate were lowered to 800 rpm and 6 L/min, respectively.

• Mycobiology
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• v.40 no.4
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• pp.236-243
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• 2012

Pleurotus nebrodensis is an edible and commercially available mushroom in Korea. This study was conducted in order to evaluate the anticancer and immunopotentiating activities of crude polysaccharides, extracted in methanol, neutral saline, and hot water (hereafter referred to as Fr. MeOH, Fr. NaCl, and Fr. HW, respectively) from the fruiting bodies of P. nebrodensis. ${\beta}$-Glucan and protein contents in Fr. MeOH, Fr. NaCl, and Fr. HW extracts of P. nebrodensis ranged from 23.79~36.63 g/100 g and 4.45~6.12 g/100 g, respectively. Crude polysaccharides were not cytotoxic against sarcoma 180, HT-29, NIH3T3, and RAW 264.7 cell lines at a range of $10{\sim}2,000{\mu}g/mL$. Intraperitoneal injection with crude polysaccharides resulted in a life prolongation effect of 11.76~27.06% in mice previously inoculated with sarcoma 180. Treatment with Fr. NaCl resulted in an increase in the numbers of spleen cells by 1.49 fold at the concentration of $50{\mu}g/mL$, compared with control. Fr. HW improved the immuno-potentiating activity of B lymphocytes through an increase in alkaline phosphatase activity by 1.65 fold, compared with control at $200{\mu}g/mL$. Maximum production of nitric oxide ($14.3{\mu}M$) was recorded in the Fr. NaCl fraction at $200{\mu}g/mL$. Production of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), and interleukin-6 (IL-6) was significantly higher, compared to control, and IL-6 production was highest, in contrast to TNF-${\alpha}$, IL-$1{\beta}$, and positive control, concanavalin at the tested concentration of the various fractions. Results of the current study suggest that polysaccharides extracted from P. nebrodensis have a strong anticancer effect and may be useful as an ingredient of biopharmaceutical products for treatment of cancer.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.4
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• pp.162-165
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• 2006

The selective growth of InCaN/AlGaN light emitting diodes was performed by mixed-source hydride vapor phase epitaxy (HVPE). In order to grow the InGaN/AlGaN heterosturcture consecutively, a special designed multi-sliding boat was employed in our mixed-source HVPE system. Room temperature electroluminescence spectum of the SAG-InGaN/AlGaN LED shows an emission peak wavelength of 425 nm at injection current 20 mA. We suggest that the mixed-source HVPE method with multi-sliding boat system is possible to be one of the growth methods of III-nitrides LEDs.