• Archives of Pharmacal Research
• /
• 제16권2호
• /
• pp.140-146
• /
• 1993

A colostral protein that augments natural killer (NK) cell activity was isolated from bovine colostrum. This protein, designated matemal immunity enhancing factor (MIEF), increased NK cell-mediated cytotxicity against human tumor targets wheb added to cultures of resting peripheral blood lymphocytes. The NK cell stimulatory activity of the MIEF was demonstrated at the concentrations as low as 0.1-0.01 $\mu$g/ml. Purified MIEF showed an apparent molecular weight of 22,000 in SDS-polyacrylamide gel electrophoresis. The unusual biochemical characteristics of the MIEF distinguish it from other cytokines. The MIEF was soluble at a cold tgemperature, and precipitated by raising the temperature. This themal precipitability was reversible, and dependent on the concentration, pH and ionic strength. Maximal precipitation was observed at neutral pH, and higher ionic strength.

• 대한약침학회지
• /
• 제25권4호
• /
• pp.364-368
• /
• 2022

Objectives: Verbenalin is a compound found in herbs such as Cornus officinalis and Verbena officinalis. This study investigated whether verbenalin is safe by analyzing its mutagenicity. Methods: To examine the mutagenic potential of verbenalin, a bacterial reverse mutation test (Ames test) was conducted with Salmonella typhimurium and Escherichia coli strains. Experiments with and without metabolic activity were performed. Results: The mean colony number was less than double that of the control. Growth inhibition and precipitation of verbenalin were not apparent in all strains at different concentrations regardless of metabolic activity. Conclusion: Verbenalin did not show any signs of mutagenicity in this study. Additional toxicity studies including repeated oral toxicity, reproductive toxicity, and carcinogenicity tests are needed.

• Asian-Australasian Journal of Animal Sciences
• /
• 제17권10호
• /
• pp.1447-1451
• /
• 2004

An experiment was conducted to determine the effects of different dietary crude protein (CP) levels on growth performance, nutrient utilization, small intestine protease activity and immunity index of weaner to 2 month-old New Zealand rabbits. Eighty weaner rabbits were allocated in individual cages to five treatments in which they were fed diets with CP at 14%, 16%, 18%, 20% and 22%, respectively. The growth performance and nutrient digestibility of rabbits increased firstly when dietary CP increased, then decreased. The average daily gain was the highest and feed conversion rate was the lowest when dietary CP reached 20%, namely 34.9 g/d and 2.74:1, respectively. Maximum CP digestibility was 72.1% in the 18% CP group, maximum crude fiber digestibility of 28.4% occurred in the 16% CP group and was significantly different from other treatments (p<0.01), apparent digestibility of Lys and Val followed the same trend as CP digestibility, and reached their maximum when dietary CP was 18%. Apparent digestibility of Cys, Tyr, Leu and Thr also had a similar trend to CP digestibility. Nitrogen retention (RN) increased with CP level (p>0.05), and was highest for 20% CP treatment (1.5 g/d). The effect of CP level on the rate of digestible nitrogen (DN) converted RN was small. The spleen index, thymus index, chymotrypsin and trypsin activities in small intestine were highest when dietary CP was 16%, which were 1.0, 2.8, 15.7 U/g and 125.7 U/g, respectively. There was no significant difference among treatments (p>0.05). According to the above results, the appropriate dietary CP level from weaner to 2 month-old meat rabbits was 18-20%.

• 한국지구과학회지
• /
• 제27권6호
• /
• pp.591-605
• /
• 2006

본 연구는 달의 일주 운동에서 관찰되는 월면 무늬의 겉보기 회전 운동에 관해서 정량적으로 기술하고 관측 결과를 제시하여 지구과학 교과 관점에서 지구 자전 현상과의 연관성을 고찰하였다. 이러한 연구를 통하여 달의 일주 운동 관측이 지구과학 교과 영역에서 수행할 수 있는 탐구활동 소재 중의 하나로 구성될 수 있다는 것을 제시하고자 한다. 월면 무늬 회전은 지표면에 서 있는 관측자가 일주 운동하고 있는 달을 보고 있을 때 달 표면에 있는 어두운 무늬들이 지평선에 대해서 회전하고 있는 것처럼 보이는 현상이다. 이 현상은 육안으로도 쉽게 관측되므로 지구과학 탐구 요소로서 의문을 품어볼 만한 자연현상임에도 불구하고 이 현상을 지구 자전과 관련된 내용으로 소개하고 있는 지구과학 전공 영역 서적을 찾아보기가 쉽지 않다. 따라서 본 연구에서는 월면 회전 현상의 이론적인 원리를 수학적으로 상세히 유도하고, 실제관측을 통하여 이 현상이 지구과학 교과 영역의 탐구 소재로서 개발될 수 있는 가능성을 제시하였다. 또한 월면의 역회전 현상을 제시하고, 이를 수학적으로 증명하였으며 정성적인 이해가 가능하도록 설명 방법을 고안하여 소개하였다.

• 한국초지조사료학회지
• /
• 제34권1호
• /
• pp.15-20
• /
• 2014

To investigate lignification process and its physiological significance under water-deficit condition, the responses of peroxidases, polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) in relation to leaf water status to the short term of water deficit treatment in the leaves with different maturities in forage rape were measured. The significant decrease in relative water content (RWC) and leaf osmotic potential (${\Psi}{\pi}$) were apparent after 5 d of water-deficit treatment. The activity of guaiacol peroxidase (GPOD), ascorbate peroxidase (APOD), coniferyl alcohol peroxidase (CPOD), and syringaldazine peroxidase (SPOD) was depressed especially in middle and old leaves when compared with that of control leaves. On the other hand, in young leaves, a significant increase in CPOD (+34%) and SPOD (+24%) activity as affected by water-deficit treatment was apparent. The activation of PAL and PPO was observed in middle and old leaves for PAL and in young and middle leaves for PPO. These results suggest that peroxidases in middle and old leaves did not involve in lignification under mild water-deficit stress, whereas CPOD and SPOD in young leaves participate in lignification by a coordination with PAL and PPO to incorporate phenol and lignin into the cell walls.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제9권6호
• /
• pp.423-427
• /
• 2004

A simple purification procedure of bioactive human granulocyte macrophage colony stimulating factor (hGM-CSF) secreted in rice cell suspension culture has previously been described. In this study the protein was purified to apparent homogeneity with an overall yield of $80.1\%$ by ammonium sulfate precipitation and a single chromatographic step involving FPLCanion exchange chromatography. The purified hGM-CSF revealed at least five glycosylated forms ranging from $21.5{\~}29$ kDa, and its biological activity was independent of the glycosylation pattern. This is the first purification report of recombinant hGM-CSF to apparent homogeneity from rice cell suspension cultures.

• 한국재료학회지
• /
• 제26권8호
• /
• pp.406-411
• /
• 2016

In order to reuse the photocatalyst and enhance the photolysis efficiency, we have used atmospheric pressure dielectric barrier discharge (APDBD) to clean and activate $TiO_2$ powder. The photocatalytic activity of the $TiO_2$ powder before and after APDBD treatment was evaluated by the degradation of methylene blue (MB) in aqueous solution. The apparent reaction rate constant of photolysis of the first sample of reused $TiO_2$ cleaned by APDBD improved to a level up to 0.32h-1 higher than the 30 % value of the initial $TiO_2$ powder. As the number of photolysis reactions and APDBD cleanings increased, the apparent rate constants gradually decreased; however, the fourth photolysis reaction still showed a value that was greater than 10% of the initial value. In addition, APDBD treatment enhanced the process by which $TiO_2$ effectively adsorbed MB at every photolysis stage.

• BMB Reports
• /
• 제32권5호
• /
• pp.429-435
• /
• 1999

Unlike the mammalian glucose transporter GLUT1, little is known about the nature of the endogenous sugar transporter(s) in insect cells. In order to establish the transport characteristics and other properties of the sugar transport proteins of Sf9 cells, a series of kinetic analyses was performed. A saturable transport system for hexose uptake has been revealed in the insect cells. The apparent affinity of this transport system(s) for 2-deoxy-D-glucose was relatively high, the $K_m$ for uptake being <0.5 mM. To further investigate the substrate and inhibitor recognition properties of the insect cell transporter, the ability of other sugars or drugs to inhibit 2-deoxy-D-glucose transport was examined by measuring inhibition constants ($K_j$). Transport was inhibited by D-mannose, D-glucose, and D-fructose. However, the apparent affinity of the C-4 epimer, D-galactose, for the Spodoptera transporter was relatively low, implying that the hydroxyl group at the C-4 position may play a role in the strong binding of glucose and mannose to the transporter. The results also showed that transport was stereoselective, being inhibited by D-glucose but not by L-glucose. It is therefore concluded that insect cells contain an endogenous glucose transport activity that in several aspects resembles the human erythrocyte glucose transporter. However, the mammalian and insect transporters were different in some of their kinetic properties, namely, their affinities for fructose and for cytochalasin B.

• Journal of Nutrition and Health
• /
• 제30권3호
• /
• pp.266-276
• /
• 1997

To investigate the effects of dietary protein and calcium levels on calcium and bone metabolism Sprague-Dawley male growing rats weighting approximately 91.4g were divided into four groups and fed one of the following four experimental diets-15% protein 0.2% calcium ; 15% protein 0.5% calcium ; 30% protein 0.2% calcium ; 30% protein 0.5% calcium-for five weeks. Calcium intake and excretion, apparent calcium absorption were measured and bone densities and mineral contents of femur and scapula were analyzed. Calcium excretion through feces and urine was significantly greater in animals receiving diets of higher calcium. Fecal calcium but not urinary calcium excretion was greater when the protein level was increased from 15% to 30%. Apparent calcium absorption rate was significantly higher with lower calcium intakes. Serum alkaline phosphatase activity was significantly higher in 0.2% calcium group than in 0.5% calcium group, while urinary hydroxyproline excretion was essentially same among all experimental groups. Weights and mineral contents or protein. Bone weights were greater, but calcium and ash contents of femur and scapula were lower in animals on the diet containing low calcium and high protein, which suggests that bone metabolism may be affected by the interaction between calcium and protein intake. These results indicate that during growth high protein intake might be beneficial to bone health if the diet is sufficient in calcium, however, if the diet fails to provide an optimum amount of calcium, such practice might be detrimental.

• BMB Reports
• /
• 제31권1호
• /
• pp.77-82
• /
• 1998

To purify the geranylgeranyl protein transferase type I (GGPT-I) efficiently, a gene expression system using the pGEX-4T-1 vector was constructed. The cal1 gene, encoding the ${\beta}$ subunit of GGPT-I, was subcloned into the pGEX-4T-1 vector and co-transformed into E. coli cells harboring the ram2 gene, the ${\alpha}$ subunit gene of GGPT-I. GGPT-I was highly expressed as a fusion protein with glutathione S-transferase (GST) in E. coli, purified to homogeneity by glutathione-agarose affinity chromatography, and the GST moiety was excised by thrombin treatment. The purified yeast GGPT-I showed a dose-dependent increase in the transferase activity, and its apparent $K_m$ value for an undecapeptide fused with GST (GST-PEP) was $0.66\;{\mu}M$ and the apparent value for geranylgeranyl pyrophosphate (GGPP) was $0.071\;{\mu}M$.