• Title/Summary/Keyword: $\mu$ synthesis

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Novel Bombesin Analogues Conjugated with DOTA-Ala(SO3H)-4 aminobenzoic acid and DOTA-Lys(glucose)-4 aminobenzoic acid: Synthesis, Radiolabeling, and Gastrin Releasing Peptide Receptor Binding Affinity

  • Lim, Jae Cheong;Choi, Sang Mu;Cho, Eun Ha;Kim, Jin Joo
    • Journal of Radiation Industry
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    • v.7 no.2_3
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    • pp.191-200
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    • 2013
  • In this study, a novel bombesin (BBN) analogues, DOTA-Ala($SO_3H$)-4 aminobenzoyl-Gln-Trp-Ala-Val-Gly-His-Leu-Met-$NH_2$ (DOTA-sBBN) and DOTA-Lys(glucose)-4 aminobenzoyl-Gln-Trp-Ala-Val-Gly-His-Leu-Met-$NH_2$ (DOTA-gluBBN), were synthesized and radiolabeled, and their binding affinities were evaluated. Peptides were prepared by a solid phase synthesis method and their purities were over 98%. DOTA is the chelating agent for $^{177}Lu$-labeling, and the DOTA-conjugated peptides were radiolabeled with $^{177}Lu$ by a high radiolabeling yield (>98%). The Log P values of DOTA-sBBN and DOTA-gluBBN were -2.20 and -2.79, respectively. 50.41% of $^{177}Lu$-DOTA-sBBN and 72.97% of $^{177}Lu$-DOTA-gluBBN were left undegraded by the serum incubation at $37^{\circ}C$ for 48 hr. A competitive displacement of $^{125}I-[Tyr^4]$-BBN on the PC-3 human prostate carcinoma cells revealed that 50% inhibitory concentration ($IC_{50}$) were 1.46 nM of DOTA-sBBN and 4.67 nM of DOTA-gluBBN indicating a highly nanomolar binding affinity for GRPR. Therefore, it is concluded that $^{177}Lu$-DOTA-sBBN and $^{177}Lu$-DOTA-gluBBN can be potential candidates as a targeting modality for the Gastrin-releasing peptide receptor (GRPR)-over-expressing tumors, and further studies to evaluate their biological and pharmacological characteristics are needed.

Study on Manufacture of High Purity TiCl4 and Synthesis of High Purity Ti Powders (고순도 TiCl4 제조 및 이를 활용한 고순도 Ti 분말 제조 공정 연구)

  • Lee, Jieun;Yoon, Jin-Ho;Lee, Chan Gi
    • Journal of Powder Materials
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    • v.26 no.4
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    • pp.282-289
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    • 2019
  • Ti has received considerable attention for aerospace, vehicle, and semiconductor industry applications because of its acid-resistant nature, low density, and high mechanical strength. A common precursor used for preparing Ti materials is $TiCl_4$. To prepare high-purity $TiCl_4$, a process based on the removal of $VOCl_3$ has been widely applied. However, $VOCl_3$ removal by distillation and condensation is difficult because of the similar physical properties of $TiCl_4$ and $VOCl_3$. To circumvent this problem, in this study, we have developed a process for $VOCl_3$ removal using Cu powder and mineral oil as purifying agents. The effects of reaction time and temperature, and ratio of purifying agents on the $VOCl_3$ removal efficiency are investigated by chemical and structural measurements. Clear $TiCl_4$ is obtained after the removal of $VOCl_3$. Notably, complete removal of $VOCl_3$ is achieved with 2.0 wt% of mineral oil. Moreover, the refined $TiCl_4$ is used as a precursor for the synthesis of Ti powder. Ti powder is fabricated by a thermal reduction process at $1,100^{\circ}C$ using an $H_2-Ar$ gas mixture. The average size of the Ti powder particles is in the range of $1-3{\mu}m$.

Inhibitory effects of crude polysaccharide fractions from Annona muricata L. on melanogenesis (그라비올라 잎(Annona muricata L.) 조다당 분획분의 멜라닌 생성 저해 효과)

  • Kim, Yi-Eun;Byun, Eui-Hong
    • Korean Journal of Food Science and Technology
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    • v.51 no.1
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    • pp.52-57
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    • 2019
  • The objective of this study was to evaluate the anti-melanogenic effects of crude polysaccharide fractions from Annona muricata L. (ALP) in 3-isobutyl-1-methylxanthine (IBMX) stimulating hormone-induced mouse B16F10 melanoma cells. The inhibitory effect of ALP on tyrosinase activity was approximately $33.88{\pm}0.79%$ at 5 mg/mL. Additionally, the B16F10 cellular tyrosinase and melanin synthesis inhibition activities by ALP were $54.21{\pm}4.76$ and $56.74{\pm}6.97%$ at $250{\mu}g/mL$, respectively. Similarly, whitening-related protein tyrosinase, tyrosinase-related protein 1 (TRP-1) and TRP-2, and microphthalmia-associated transcription factor (MITF) were reduced by ALP treatment. These results indicated that ALP could be used as a functional cosmetic ingredient after confirming its whitening activity related to melanin content.

Red Ginseng Alters Lipid Metabolism through AMPK Activation in Liver and Adipose Tissues of High-Fat Diet-Fed Mice (홍삼 복합 추출물의 AMPK 활성화를 통한 고지혈증 개선)

  • Jeong, Ha Jin;Oh, Seung Tack;Liu, Quan Feng;Choi, Yura;Lee, Seoungmi;Jeon, Songhee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.8
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    • pp.910-918
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    • 2017
  • Hyperlipidemia is known as a glucose and lipid metabolism-related disorder that is increasing in incidence in modern society. Red ginseng (RG) is a natural herb candidate with a positive effect on regulation of cholesterol and lipids. To observe the effects of RG on regulation of lipids, cholesterol, glucose, and oxidative stress, we examined the in vitro and in vivo effects of Chamdahan RG on differentiated 3T3-L1 adipocytes and high-fat diet-fed mice. RG ($50{\mu}g/mL$) significantly inhibited lipid synthesis in 3T3-L1 cells. In addition, a low concentration of RG (880 mg/kg/d) resulted in the lowest total blood cholesterol level. Moreover, high density lipoprotein-cholesterol quantity increased in RG-treated groups, consequently lowering the cardiovascular risk factor and atherosclerosis index. Moreover, RG increased activity of AMP-activated protein kinase, as a regulator of lipid and cholesterol synthesis, in adipose and liver tissues. Cumulatively, this paper suggests that RG has a positive effect on reducing the amounts of cholesterol and lipids and may be a good candidate for treating hyperlipidemia.

Synthesis of TiO2 Fine Powder by Sol-Gel Process and Reaction Mechanism(II) : Hydrolysis of Titanium n-Propoxide (졸-겔법에 의한 TiO2미분말 합성과 반응메카니즘(II): Titanium n-propoxide의 가수분해)

  • Myung, Jung-Jae;Park, Jin-koo;Chung, Yong-Sun;Kyong, Jin-Bum;Kim, Ho-Kun
    • Applied Chemistry for Engineering
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    • v.8 no.5
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    • pp.777-783
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    • 1997
  • $TiO_2$ powders were synthesized via hydrolysis reaction of titanium n-propoxide in n-propanol solvent and the reaction rates were studied by use of UV-vis spectroscopic method. Concentration of water, reaction temperature, reaction time and acid-base effects of the solution were investigated to determine the optimum conditions for $TiO_2$ powder synthesis. The reaction were controlled to proceed to pseudo-first orders reaction in the presence of excess water in n-propanol solvent. The rate constants which varied with temperature and concentration of water were calculated by Guggenheim method. Reaction using $D_2O$ was also carried out to determine the catalytic character of water. $TiO_2$ powders were synthesized only in the neutral and basic solution and those were almost spheric forms having average particle size of $0.4-0.7{\mu}m$ diameter. Particle size decreased with increasing concentration of water and reaction temperature, however, increased with increasing reaction time. Associative $S_N2$ mechanism for the hydrolysis was proposed from the data of n-value in the transition state and thermodynamic parameter. $D_2O$ solvent isotope effect showed that $H_2O$ molecules reacted as nucleophilic catalysis.

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Optimization of Glycosyl Aesculin Synthesis by Thermotoga neapolitana β-Glucosidase Using Response-surface Methodology (반응표면분석법을 이용한 Thermotoga neapolitana β-glucosidase의 당전이 활성을 통한 glycosyl aesculin 합성 최적화)

  • Park, Hyunsu;Park, Young-Don;Cha, Jaeho
    • Journal of Life Science
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    • v.27 no.1
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    • pp.38-43
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    • 2017
  • Glycosyl aesculin, a potent anti-inflammatory agent, was synthesized by transglycosylation reaction, catalyzed by Thermotoga neapolitana ${\beta}-glucosidase$, with aesculin as an acceptor. The key reaction parameters were optimized using response-surface methodology (RSM) and $2{\mu}g$ of the enzyme. As shown by a statistical analysis, a second-order polynomial model fitted well to the data (p<0.05). The response surface curve for the interaction between aesculin and other parameters revealed that the aesculin concentration and reaction time were the primary factors that affected the yield of glycosyl aesculin. Among the tested factors, the optimum values for glycosyl aesculin production were as follows: aesculin concentration of 9.5 g/l, temperature of $84^{\circ}C$, reaction time of 81 min, and pH of 8.2. Under these conditions, 61.7% of glycosyl aesculin was obtained, with a predicted yield of 5.86 g/l. The maximum amount of glycosyl aesculin was 6.02 g/l. Good agreement between the predicted and experimental results confirmed the validity of the RSM. The optimization of reaction conditions by RSM resulted in a 1.6-fold increase in the production of glycosyl aesculin as compared to the yield before optimization. These results indicate that RSM can be effectively used for process optimization in the synthesis of a variety of biologically active glycosides using bacterial glycosidases.

Study of Skin Depigmenting Mechanism of the Ethanol Extract of Fagopyrum esculentum (교맥 에탄올 추출물의 피부 미백기전 연구)

  • No, Seong-Taek;Kim, Dae-Sung;Lee, Seong-Jin;Park, Dae-Jung;Lee, Jang-Cheon;Lim, Kyu-Sang;Woo, Won-Hong;Mun, Yeun-Ja
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.5
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    • pp.1243-1249
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    • 2007
  • The aim of this study was to investigate the effect of ethanol extract of Fagopyrum esculentum on the melanogenesis. To determine whether ethanol extract of Fagopyrum esculentum suppress melanin synthesis in cellular level, B16F10 melanoma cells were cultured in the presence of different concentrations of Fagopyrum esculentum ethanol extract. In the present study, we examined the effects of Fagopyrum esculentum ethanol extract on cell proliferation, melanin contents, tyrosinase activity, expression of melanogenic enzyme proteins including tyrosinase, tyrosinase-related protein 1 (TRP-1) and tyrosinase-related protein 2 (TRP-2). Cell proliferation was slightly increased by treatment with ethanol extract of Fagopyrum esculentum $(25-200 {\mu}g/m{\ell}).$ The ethanol extract of Fagopyrum esculentum effectively suppressed melanin contents at a dose of $100 {\mu}g/m{\ell}).$ It was observed that the color of cell pellets was totally whitened compared with the control. The ethanol extract of Fagopyrum esculentum inhibited tyrosinase activity, regulate melanin biosynthesis as the key enzyme in melanogenesis. Using western blot analysis, the ethanol extract of Fagopyrum esculentum dose-dependently decreased tyrosinase and TRP-1 protein levels, and tyrosinase and TRP-1 were detected in similar manner. ${\alpha}-MSH$ leads to a stimulation of melanin synthesis through increase of tyrosinase activity, melanin contents and cytoplasmic dendricity. In this study, ethanol extract of Fagopyrum esculentum down-regulated the ${\alpha}-MSH$-induced tyrosinase activity, melanin contents and cytoplasmic dendricity. Regarding protein levels of the melanogenic enzymes, the amounts of tyrosinase and TRP-1 was increased after incubation with a-MSH. The treatment of ethanol extract of Fagopyrum esculentum decreased the ${\alpha}-MSH$-induced expression levels of tyrosinase and TRP-1. These results suggest that the ethanol extract of Fagopyrum esculentum exerts its depigmenting effects through the suppression of tyrosinase, TRP-1 and cytoplasmic dendricity. And it may be a potent depigmetation agent in hyperpigmentation condition.

Profile Analysis of Proteins Related with Hydrogen Peroxide Response in Strep-tomyces coelicolor (Muller) (Streptomyces coelicolor (Muller)의 과산화수소 대응 반응에 관련된 단백질 양상의 분석)

  • 정혜정;노정혜
    • Korean Journal of Microbiology
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    • v.31 no.2
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    • pp.166-174
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    • 1993
  • Streptomyces coeUc%r (Muller) cells were treated with $100 \mu$M hydrogen peroxide for I hour and proteins synthesized during hydrogen peroxide stress were labeled with L-[$^{35}S$]-methionine. Total cellular proteins were extracted and analyzed by two-dimensional polyacrylamide gel electrophoresis. In exponential growth phase, synthesis of about 100 proteins was increased by hydrogen peroxide treatment. These proteins were named as Pin (£eroxide-inducib]e) proteins and classified into 4 subgroups according to their induction time after hydrogen peroxide treatment. About 60 of them were found to be induced within 20 minutes and maintained throughout I hour of treatment. In stationary growth phase. synthesis of 62 proteins was increased by hydrogen peroxide and 21 of them were the same Pins found in exponential growth phase. Proteins from the mutants which are resistant to hydrogen peroxide were obtained in exponential growth phase and compared with those from the wild type on two-dimensional gel. The three mutants, N7, N9. and N24, were found to have higher constitutive leve]s of ]5, 17, and 15 Pin proteins respectively, than the wild type. 9 of these Pin proteins (D74.7a, E76.0c, E23.3. F50.7, F47.2a. F25.5, G39.6b, G24.0, H39.6a) increased in two of the three mutants and 3 proteins (F39.7, H6I.7. 120.8) increased in all of the three mutants. These proteins might play important roles in the response of S. coelic%r to hydrogen peroxide.

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Inhibitory effect of Gastrodia elata Blume extract on alpha-melanocyte stimulating hormone-induced melanogenesis in murine B16F10 melanoma

  • Shim, Eugene;Song, Eunju;Choi, Kyoung Sook;Choi, Hyuk-Joon;Hwang, Jinah
    • Nutrition Research and Practice
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    • v.11 no.3
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    • pp.173-179
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    • 2017
  • BACKGROUND/OBJECTIVES: Gastrodia elata Blume (GEB), a traditional herbal medicine, has been used to treat a wide range of neurological disorders (e.g., paralysis and stroke) and skin problems (e.g., atopic dermatitis and eczema) in oriental medicine. This study was designed to investigate whether GEB extract inhibits melanogenesis activity in murine B16F10 melanoma. MATERIALS/METHOD: Murine B16F10 cells were treated with 0-5 mg/mL of GEB extract or $400{\mu}g/mL$ arbutin (a positive control) for 72 h after treatment with/without 200 nM alpha-melanocyte stimulating hormone (${\alpha}$-MSH) for 24 h. Melanin concentration, tyrosinase activity, mRNA levels, and protein expression of microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein (Trp)1, and Trp2 were analyzed in ${\alpha}$-MSH-untreated and ${\alpha}$-MSH-treated B16F10 cells. RESULTS: Treatment with 200 nM ${\alpha}$-MSH induced almost 2-fold melanin synthesis and tyrosinase activity along with increased mRNA levels and protein expression of MITF, tyrosinase, Trp1 and Trp2. Irrespective of ${\alpha}$-MSH stimulation, GEB extract at doses of 0.5-5 mg/mL inhibited all these markers for skin whitening in a dose-dependent manner. While lower doses (0.5-1 mg/mL) of GEB extract generally had a tendency to decrease melanogenesis, tyrosinase activity, and mRNA levels and protein expression of MITF, tyrosinase, Trp1, and Trp2, higher doses (2-5 mg/mL) significantly inhibited all these markers in ${\alpha}$-MSH-treated B16F10 cells in a dose-dependent manner. These inhibitory effects of the GEB extract at higher concentrations were similar to those of $400{\mu}g/mL$ arbutin, a well-known depigmenting agent. CONCLUSIONS: These results suggest that GEB displays dose-dependent inhibition of melanin synthesis through the suppression of tyrosinase activity as well as molecular levels of MITF, tyrosinase, Trp1, and Trp2 in murine B16F10 melanoma. Therefore, GEB may be an effective and natural skin-whitening agent for application in the cosmetic industry.

The Effects of Paeonia Lactiflora Pallas on Inhibition of Oxygen Free Radical, Anti-inflammation and MMP-1 Inhibitory Activity (적작약 꽃 추출물의 활성산소 억제와 항염증 및 MMP-1 발현 억제능 효과에 관한 연구)

  • Leea, Jae-Nam;Kim, Young-Sam
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.3
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    • pp.797-806
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    • 2018
  • This study attempted to investigate the effects of Paeonia Lactiflora Pallas (P. lactiflora) on the inhibition of oxygen free radical, anti-inflammation and MMP-1 inhibitory activity and examine its possibility as a functional cosmetic material. For test methods, the inhibition of oxygen free radical after measuring reactive oxygen species (ROS) in the cell, cytotoxicity assessment and anti-inflammation were measured, and MMP-1 inhibitory effects in the HDF cell were measured. According to the test, the inhibition of ROS was confirmed in RAW 264.7 and HDF cells. In terms of cytotoxicity assessment, 90% or higher cell viability was detected at $5/10{\mu}g/mL$ Paeonia Lactiflora Pallas extract while it was 80% or higher at other concentration levels in both RAW 264.7 and HDF cells. In addition, NO production was inhibited in the RAW 264.7 cell while MMP-1 was significantly inhibited in the HDF cell. The above results reveal a possibility of Paeonia Lactiflora Pallas extract as a functional cosmetic material after confirming the inhibition of ROS synthesis in the cell, antioxidant and anti-inflammatory effects by inhibiting NO synthesis, low toxicity on skin cells and anti-aging effect through MMP-1 inhibition.