• Macromolecular Research
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• 제16권2호
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• pp.163-168
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• 2008

Polystyrene/gold nanoparticle (PS/AuNP) composite fibers were fabricated using an electrospinning technique. Transmission electron microscopy (TEM) showed that the diameters of the naphthalenethiol-capped gold nanoparticles (prior to incorporation into the PS fibers) ranged from 2 to 5 nm. UV-vis spectroscopy revealed the surface plasmon peaks of the gold nanoparticles centered at approximately 512 nm, indicating that nano-sized Au particles are well-dispersed in solution. This was consistent with the TEM observations. The electrospun nanofibers of PS/AuNP composites were approximately 60-3,000 nm in diameter. The surface morphology of the PS/AuNP composite and the dispersability of the Au nanoparticles inside of PS after electrospinning process were investigated by SEM and TEM. The thermal behavior of the pure PS and PS/AuNP nanocomposites and fibers were examined by DSC.

• 폴리머
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• 제34권2호
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• pp.144-149
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• 2010

Ag/polystyrene(PS) 나노복합체를 110 $^{\circ}C$의 가열법에 의하여 silver 2-ethylhexylcarbamate(Ag-CB) 복합체의 환원과 동시에 라디칼 중합을 진행하여 제조하였다. 또한, 이러한 전통적인 가열법과는 대조적으로 마이크로파를 조사하여 스티렌 단량체의 중합이 진행됨이 없이 은 나노입자가 잘 분산된 콜로이드 스티렌 용액을 제조할 수 있었다. 이렇게 단지 마이크로파를 조사하여 은 나노입자를 제조하는 방법은 반응기 내의 전체 용액 속에서 균일하고 빠르게 진행되어 매우 입자가 작고 균일한 은 나노콜로이드 용액을 제조할 수 있었다. 또한, 연속적으로 얻어진 은 나노입자를 포함하는 단량체 용액을 라디칼 중합시킴으로써 PS 고분자 매트릭스에 은 나노입자가 잘 분산된 Ag/PS 나노복합체를 얻을 수 있었다. Ag/PS(0.1/100) 나노복합체는 Ag/PS(4.0/100)를 마스터배치로 사용하여 용융-혼합 방법에 의하여 성공적으로 제조할 수 있었으며 그러한 나노복합체를 UV-VIS spectroscopy, TEM, 그리고 XRD를 이용하여 확인하였다.

• 공업화학
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• 제9권5호
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• pp.754-757
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• 1998

본 연구는 탈묵펄프 공정의 과산화수소 보존표백시 과산화수소 안정제 Versenate PS에 의한 silicate 대체효과를 검토하였다. 대체 가능성을 파악하기 위하여 silicate 및 Versenate PS 처리 표백시 전처리와 가성소다의 최적화 실험을 시행한 후 잔류 과산화수소의 함량과 백색도를 측정하였다. 얻은 결과를 요약하면 다음과 같다. 1. Silicate 처리 표백시 가성소다의 최적농도는 2.5~3.0%였다. 2. Versenate PS처리 표백시 가성소다의 최적농도는 1.0~1.5%였다. 3. Versenate PS 단독 처리만으로는 만족할 만한 표백효과를 나타내지 못했다. 4. Versenate PS 처리 표백시에는 silicate양을 상당량 줄일 수 있다. 5. DTPA로 전처리 하는 것이 좀 더 높은 표백효율을 나타내었다.

• Biomolecules & Therapeutics
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• 제12권2호
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• pp.79-84
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• 2004

02PS15 extracts (BuOH, $H_2O$, and crude extracts) significantly inhibited IL-4 and IL-6 secretion from the phytohemagglutinin (PHA)-plus phorbol 12-myristate 13-acetate (PMA)-induced peripheral blood mononuclear cleas (P<0.05). 02PS15 extracts (BuOH and crude extracts) also significantly inhibited the histamine release from rat peritoneal mast cells (P<0.05). Significant reduced levels (P<0.05) of PMA- and A23187-induced IL-8 were observed in the human mast cell line, HMC-1, with O2PS15 extracts (BuOH and crude extracts). 02PS15 extracts (BuOH and crude extract) downregulated the expression of IL-6 and IL-8 in the activated HMC-1. These results suggest that O2PS15 has the inhibitory effect of atopic allergic reaction anil this might be useful for clinical application to treat several allergic diseases such as atopic dermatitis.

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.207-213
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• 2012

The present study examined the effects of krill-derived phosphatidylserine (Krill-PS) on the learning and memory function and the neural activity in rats with trimethyltin (TMT)-induced memory deficits. The rats were administered vehicle (medium-chain triglyceride: MCT) or Krill-PS (50, 100 mg/kg, p.o.) daily for 21 days. The cognitive improving efficacy of Krill-PS in TMT-induced amnesic rats was investigated by assessing the Morris water maze test and by performing choline acetyltransferase (ChAT), acetylcholinesterase (AChE) and cAMP responsive element binding protein (CREB) immunohistochemistry. The rats with TMT injection showed impaired learning and memory of the tasks and treatment with Krill-PS produced a significant improvement of the escape latency to find the platform in the Morris water maze at the $2^{nd}$ and $4^{th}$ day compared to that of the MCT group (p<0.05). In the retention test, the Krill-PS+MCT groups showed increased time spent around the platform compared to that of the MCT group. Consistent with the behavioral data, Krill-PS 50+MCT group significantly alleviated the loss of acetylcholinergic neurons in the hippocampus and medial septum compared to that of the MCT group. Treatment with Krill-PS significantly increased the CREB positive neurons in the hippocampal CA1 area as compared to that of the MCT group. These results suggest that Krill-PS may be useful for improving the cognitive function via regulation of cholinergic marker enzyme activity and neural activity.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권6호
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• pp.43-51
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• 2012

Rreactivity of persulfate (PS) for oxidation of TCE under various conditions such as heat, $Fe^{2+}$, and UV was investigated. It was found that degradation rate of TCE increased with increasing temperature from 15 to $35^{\circ}C$. At pH 7.0, the rate constants (k) at 15, 25, 30, and $35^{\circ}C$ were 0.07, 0.30, 0.74, and $1.30h^{-1}$, respectively. For activation by $Fe^{2+}$, removal efficiency of TCE increased with increasing $Fe^{2+}$ concentration from 1.9 mM to 11 mM. The maximum removal efficiency of TCE was approximately 85% when pH of the solution dropped from 7.0 to 2.5. Degradation of TCE by UV-activated PS was the most effective, showing that the degradation rate of TCE increased with inreasing PS dosage; the rate constants (k) at 0.5, 2.5, and 10 mM were 34.2, 40.5, and $55.9h^{-1}$, respectively. Our results suggest that PS activation by UV/PS process could be the most effective in activation processes tested for TCE degradation. For oxidation process by PS, however, pH should be observed and adjusted to neutral conditions (i.e., 5.8-8.5) if necessary.

• 생약학회지
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• 제14권4호
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• pp.178-192
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• 1983

Polygalae Radix was used as diuretics, analgesics and expertorants in oriental medicine. The root of Polygala tenuifolia Willd. (Polygalaceae) is comprised saponin (Onjisaponin A,B,C,D,E,F and G) polygalitol, onsitin and sugars. The pharmacological action of crude Polygala-saponin (PS) obtained from the roots are studied. The following results were obtained; 1) The median lethal dose $(LD_{50})$ of PS in mice is presented 71.1mg/kg s.c. and 694. 5mg/kg p.o.. 2) PS demonstrated diuretic action of relatively long acting duration in mice. 3) The diuretic mechanism of PS was found due to inhibitory effect of renal tubular reabsorption of electrolytes and glomerular vascular dilatation. 4) The group, administered simultaneously PS and cefadroxil monobydrate was significantly increased with PS alone group on diuretic action. Synergistic effect cefadroxil monohydrate on the diuretic action of PS seems due to competitive inhibition of plasma protein binding with PS. 5) PS demonstrated analgesic action by the acetic acid stimulating method and Randall-Selitto test in mice. 6) PS presented antipyretic action against febrile treated with the typhoid vaccine. 7) PS was significantly prolonged against the hypnotic duration of pentobarbital in mice. 8) Onset time convulsion and death induced by picrotoxin and strychnine in mice were not delayed. According to the above results, the PS was identified as a pharmacological active component obtained from roots of Polygala tenuifolia Willd.

• 한국식품위생안전성학회지
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• 제13권3호
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• pp.305-312
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• 1998

서울시내 약수에서 Pseudomonas속균의 균종분포, 생화학적 특성, 혈청학적 특성 및 항생제 감수성을 조사하기 위하여 약수 57개소에 대하여 봄, 여름, 가을에 걸쳐 조사하였다. 총 57개 약수를 조사한 결과, 33개 (57.9%)의 약수에서 Pseudomonas속균이 검출되었다. 봄, 여름, 가을에 모두 검출된 곳은 1곳(1.8%) 이었으며, 2회에 걸쳐 검출된 곳은 9곳 (15.8%)이었으며, 1회만 검출된 곳은 13곳 (22.8%)이었다. 지역별로는 청계산이 50%의 검출율을 나타내었으며, 북한산, 35.7&, 대모산 33.3%, 도봉산 29.6%, 수락산 25.9%, 우면산 22.2%, 불암산 7.4% 순이었다. 분리된 균종은 Ps. putidark 22주(50%)로 가장 많았으며, Ps. aeruginosa, Ps. fluorescens 및 Ps. mendocins 각 6주(13.6%), Ps.aureofaciens 4주(9.1%)이었다. 분리된 Ps. aeruginosa6주의 혈청형은 모두 5종으로 A형 2주 , B, C,E 및 G형 각 2주씩이었다. 분리된 Ps. aeruginosa의 항생제에 대한 내성은 Amoxicillin 90.9%, Chloramphenicol 84.1%, Carbenicillin 81.8%, Nalidixic acid 68.2%, Neomycin 38.6%, Streptomycin 31.8%, Gentamicin 4.6%, Kanamycin 4.6% 그리고 Colistin 2.3%이었다. Ps.aeruginosa는 다른 슈도모나스균에 비해 carbenicillin에 대한 감수성이 있으나 kanamycin에 대한 내성이 높았다. Ps. aureofaciens는 다른 슈도모나스균에 비해 streptomycin에 대하여 내성이 없었다. 분리된 Ps.aeruginosa의 항생제에 대한 다제내성양상은 5제내성이 31.8%로 가장 높았으며, 내성양상에서는 NA-CB-CTE-AMC가 18.2%로 가장 높게 나타났다.

• 동의생리병리학회지
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• 제23권3호
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• pp.599-607
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• 2009

Prunellae Spica is the spike or whole plant of Prunella vulgaris Linne, which has been used for clearing heat from the liver, brightening the eyes and treating headache in traditional oriental medicines. This study was conducted to evaluate the inhibitory effects of the aqueous extract of Prunellae Spica (PSE; PS extract) on the production of NO and PGE2 in LPS-activated Raw 264.7 cells. Cell viability was determined by MTT assay, and all three doses of PS extract (0.03, 0.1 and 0.3 mg/ml) had no significant cytotoxicity during the entire experimental period. The cells were treated with 1 ${\mu}g/ml$ of LPS 1 h before adding PS extract, and increased NO and PGE2 production were detected in LPS-activated cells compared to control. However, these increases were dose-dependently attenuated by treatment with PS extract. The inhibition of NO by PS extract was due to the suppression of iNOS expression via inhibition of $NF{\kappa}B$ nuclear translocation and proteolytic degradation of $I{\kappa}B{\alpha}$. The decreased level of PGE2 was derived from inhibition of COX-2 activity, but expression of COX-2 protein was not affected by PS extract. Moreover, PS extract reduced the elevated production of IL-${\beta}$ and IL-6 by LPS. These results demonstrate that PS extract has inhibitory effects on the production of NO and PGE2 as a consequence of the reduction of proinflammatory cytokines, especially IL-${\beta}$ and IL-6 in LPS-activated Raw 264.7 cells.

• KSBB Journal
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• 제31권3호
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• pp.158-164
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• 2016

Plant growth promoting (PGP) hormones, which are produced in a small quantity by bacteria, affect in plant growth and development. PGPs play an important role on the crop productivity in agricultural field. In this study, a photosynthetic bacterial strain producing the PGP was isolated from paddy soil. Bacterial isolate was gram negative, rod-shaped and motility positive. From the 16s rRNA gene sequence analysis, the isolate was identified as Rhodobacter capsulatus PS-2. The mass cultivation of R. capsulatus PS-2 was optimized by considering of the carbon, nitrogen and inorganic salt sources. Optimal medium composition was determined as Na-succinate 4.5 g, yeast extract 5 g, $K_2HPO_4$ 1 g, $MgSO_4$ 5 g, per liter. From the result of 500 L fermentation for 2 days using the optimal medium, the viable cells were $8.7{\times}10^9cfu/mL$. R. capsulatus PS-2 strain produced the carotenoid and indole-3-acetic acid (IAA). The carotenoid extraction and quantitative analysis were performed by HCl-assisting method. Total carotenoid contents from R. capsulatus PS-2 culture broth were measured as $7.02{\pm}0.04$ and $6.93{\pm}0.05mg/L$ under photoheterotrophic and chemoheterotrophic conditions, respectively. To measure the productivity of IAA, colorimetric method was employed using Salkowski reagent at optical density 535 nm. The results showed that the highest content of IAA was $197.44{\pm}5.92mg/L$ in the optimal medium supplemented with 0.3% tryptophan.