• Progress in Medical Physics
• /
• v.29 no.1
• /
• pp.29-41
• /
• 2018

The objective of this study was to evaluate the chemical exchange saturation transfer (CEST) effect of amino acids and neurotransmitters, which exist in the human brain, depending on the concentration, pH, and amplitude of the saturation radiofrequency field. Phantoms were developed with asparagine (Asn), ${\gamma}-aminobutyric$ acid (GABA), glutamate (Glu), glycine (Gly), and myoinositol (MI). Each chemical had three different concentrations of 10, 30, and 50 mM and three different pH values of 5.6, 6.2, and 7.4. Full Z-spectrum CEST images for each phantom were acquired with a continuous-wave radiofrequency (RF) saturation pulse with two different $B_1$ amplitudes of $2{\mu}T$ and $4{\mu}T$ using an animal 9.4T MRI system. A voxel-based CEST asymmetry was mapped to evaluate exchangeable protons based on amide (-NH), amine ($-NH_2$), and hydroxyl (-OH) groups for the five target molecules. For all target molecules, the CEST effect was increased with increasing concentration and B1 amplitude; however, the CEST effect with varying pH displayed a different trend depending on the characteristics of the molecule. On CEST asymmetric maps, Glu and MI were well visualized around 3.0 and 0.9 ppm, respectively, and were well separated macroscopically at a pH of 7.4. The exchange rates of Asn, Glu, BABA, and Gly usually decreased with increasing pH. The CEST effect was dependent on the concentration, acidity of the target molecules, and B1 amplitude of the saturation RF pulse. The CEST effect for Asn can be observed in a 9.4T MRI system. The results of this study are based on applying the CEST technique in patients with neurodegenerative diseases when proteins in the brain are increased with disease progression.

• Applied Biological Chemistry
• /
• v.51 no.3
• /
• pp.177-182
• /
• 2008

This study was carried out to investigate the reaction of lipase-catalyst transesterification using animal fat recovered from fleshing scrap generated during leather making process. Transesterification reaction between fat and primary or secondary alcohol was carried out under the condition of immobilized enzyme catalyst. The conversion rate was the highest when 1.5 mole of methanol was injected by 4 times. As for lipase, Candida antarctica showed the highest conversion rate of 82.2% among the 4 different lipases. It was found that water contained in the fat causes lower conversion rate. The condition of 1.2wt. % of water in the fat decreased the conversion rate by 40%. It was considered that the resulted reactant, fatty acid ester could be used as raw material for biodiesel with the characteristics of not generating SOx and diminishing smoke.

• Reproductive and Developmental Biology
• /
• v.31 no.4
• /
• pp.267-272
• /
• 2007

Human embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo and have the capacity to differentiate into various types of cells in the body. Hence, these cells may potentially be an indefinite source of cells for cell therapy in various degenerative diseases including neuronal disorders. For clinical applications of human ES cells, directed differentiation of these cells would be necessary. The objective of this study is to develop the culture condition for the expansion of neural precursor cells derived from human ES cells. Human ES cells were able to differentiate into neural precursor cells upon a stepwise culture condition. Neural precursor cells were propagated up to 5000-fold in cell numbers over 12-week period of culture and evaluated for their characteristics. Expressions of sox1 and pax6 transcripts were dramatically up-regulated along the differentiation stages by RT-PCR analysis. In contrast, expressions of oct4 and nanog transcripts were completely disappeared in neural precursor cells. Expressions of nestin, pax6 and sox1 were also confirmed in neural precursor cells by immunocytochemical analysis. Upon differentiation, the expanded neural precursor cells differentiated into neurons, astrocytes, and oligodendrocytes. In immunocytochemical analysis, expressions of type III ${\beta}$-tubulin and MAP2ab were observed Presence of astrocytes and oligodendrocytes were also confirmed by expressions of GFAP and O4, respectively. Results of this study demonstrate the feasibility of long-term expansion of human ES cell-derived neural precursor cells in vitro, which can be a potential source of the cells for the treatment of neurodegenerative disorders.

• Journal of Embryo Transfer
• /
• v.29 no.2
• /
• pp.149-155
• /
• 2014

The present study was designed to observe the oestrus responses in the indigenous ewe induced by cloprostenol sodium manufactured by two different companies ($Ovuprost^{(R)}$, BOMAC, Newzealandand $Prostenol^{(R)}$, Techno, Bangladesh). Twelve local ewes were divided into 3 groups (n= 8). The ewes in Group I and II were induced by intramuscular injection of $100{\mu}g$ (0.4 ml) of cloprostenol sodium ($Ovuprost^{(R)}$ and $Prostenol^{(R)}$), respectively. The $2^{nd}$ injection in each group was given at 9 days apart. The ewes in Group III were kept as control for observing natural oestrus characteristics and comparing the responses with induced oestrus. Hundred and 75% ewes showed oestrus following $2^{nd}$ injection of $Ovuprost^{(R)}$ and $Prostenol^{(R)}$, respectively. The average time of onset of oestrus following $1^{st}$ and $2^{nd}$ injection of $Ovuprost^{(R)}$ and $Prostenol^{(R)}$ were $50.5{\pm}3.5$ vs $48.0{\pm}0.0h$ and $49.9{\pm}1.9$ vs $49.5{\pm}1.7h$, respectively. There was no significant difference between the two types of cloprostenol sodium group on the onset of oestrus. The average duration of oestrus was $27.5{\pm}0.7$ vs $27.5{\pm}0.0h$ and $25.9{\pm}3.3$ vs $24.2{\pm}0.3h$ in $Ovuprost^{(R)}$ and $Prostenol^{(R)}$ treated ewes, respectively. For natural oestrus, the duration of oestrus was $25.2{\pm}3.3h$. There was no significant difference among the cloprostenol sodium produced by two different companies and natural oestrous ewes on the duration of oestrus. The higher percentages of cornified cells were present in induced oestrus (90 and 85%) compared with natural oestrus (80%), although there was no significant difference among them. The pregnancy rates were 75, 66.7 and 100% in $Ovuprost^{(R)}$, $Prostenol^{(R)}$ and natural oestrous ewes, respectively. The above results indicate the suitability of using cloprostenol sodium for synchronization of oestrus in indigenous ewes in Bangladesh.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.2
• /
• pp.167-176
• /
• 1999

Shoot morphological characteristics were affected by plant population densities in alfalfa. Shoots per plant, yield per shoot, yield per plant, and stem diameter increased with decreasing alfalfa population density. Winter survival was maximized at a plant population of $45plants\;m^{-2}$ or less. The grams of TNC per root increased as the stand density decreased. The lowest LT 50 occurred at the lowest stand density ($16plants\;m^{-2}$ having 25 cm plant spacing) and the highest LT 50 was attained at the highest stand density($494plants\;m^{-2}$ having 4.5 cm plant spacing). There were no differences in shoot morphology, winter survival, and cold hardiness in between 'Algonquin'and 'Vernal'. From this study, high stand density of alfalfa ($278plants\;m^{-2}$ or more) appears to be of little advantage compared to low stand density in terms of winter survival and cold hardiness.

• Applied Biological Chemistry
• /
• v.18 no.3
• /
• pp.117-122
• /
• 1975

In order to utilize the agricultural waste products for animal feeds, studies have been made concerning the production of cellulase of Irpex lacteus and its properties of crude enzyme, and summarized as follows. 1. At the production of cellulase, the culture of wheat bran added with rice bran was more active than any other cultures. 2. The optimum incubation time is 5 days in shaking culture. 3. The optimum condition of reaction in saccharification with CMC were obtained the following results. 1) The optimum pH was within the range of from 3.5 to 4.0 and stable within 3.0 to 6.0. 2) The optimum temperature was $40^{\circ}C$ and thermal stability was below $40^{\circ}C$. 3) The optimum reaction time was 2 hours. 4) The optimum crude enzyme concentration was 50%V/V and substrate concentration 1%.

• Proceedings of the KSAR Conference
• /
• 2001.03a
• /
• pp.9-9
• /
• 2001

내분비계 장애물질 중 관찰물질로 지정된 bisphenol A(BPA)의 투여가 생쥐의 번식 효율에 미치는 영향을 규명하기 위하여 웅성 ICR 생쥐에 무처리구, corn oil, 0.05, 0.5 및 5.0mg BPA/kg b.w의 BPA을 3일 간격으로 5회 투여했으며, 자성 ICR 생쥐도 웅성생쥐와 동일하게 3일 간격으로 5회 투여한 후, 웅성은 투여후 2일, 자성은 7일후에 모든검사를 실시하였다. BPA의 투여가 웅성 생쥐의 번식기관무게에 미치는 영향을 조사한 결과는 체중, 정소상체, 정낭선 및 응고선의 무게는 투여구간에 커다란 차이가 없었으며(P>0.05), 정소의 무게는 5.0mg 투여구가 여타구보다 다소 낮은 무게를 나타냈다. BPA의 투여가 웅성 생쥐의 정액성상에 미치는 영향을 조사한 결과, 생존율과 유효 정자수는 각 투여구간에 커다란 차이가 없었으나 총정자수는 각각 35.50, 35.73, 36.33, 33.13 및 29.28$\times$$10^{7}$ 정자/$m\ell$로서 5.0mg 투여구가 여타구보다 통계적으로 유의하게 낮은 결과을 나타냈다(P<0.05). 기형율은 5.0mg 투여구가 23.15%로서 무처리구(18.13%), 대조구(18.58%) 및 0.05mg 투여구(19.68%)보다 통계적으로 유의하게 높은 기형율을 나타냈다(P<0.05). 웅성 생쥐에 BPA의 투여가 혈액의 일반성분에 미치는 영향을 조사한 결과, RBC, Hb, HT, MCV, MCH 및 MCHC는 각 투여구간에 차이가 없었으며, WBC는 BPA 투여구가 무처리구 및 대조구보다 다소 낮은 수치를 나타냈으며, PLT는 BPA 투여구가 무처리구 및 대조구보다 높은 수치를 나타냈다. BPA의 투여가 자성 생쥐의 번식기관무게에 미치는 영향을 조사한 결과, 체중은 투여구간에 커다란 차이가 없었으며 자궁의 무게는 BPA 투여구가 대조구에 비해 다소 논은 무게를 나타냈다. 오른쪽 난소의 무게는 0.5mg 투여구와 5.0mg 투여구가 각각 0.0059 및 0.0061g으로 대조구(0.0081g)와 0.05mg 투여구(0.0071g)보다 낮은 무게를 나타냈으며, 왼쪽 난소의 무게는 각각 0.0076, 0.0076, 0.0058 및 0.0061g으로 0.5mg 투여구가 대조구와 0.05mg 투여구보다 낮은 무게를 나타냈다(P<0.05). BPA의 투여가 자성 생쥐의 혈구화학치에 미치는 영향을 조사한 결과, RBC, Hb, HT, MCV, MCH 및 MCHC는 각 투여구간에 차이가 없었으며, WBC는 BPA 투여구가 대조구보다 다소 높은 수치를 나타냈다. PLT는 0.5mg 투여구와 5.0mg 투여구가 대조구보다 다소 높은 수치를 나타냈다. 정소, 난소 및 자궁의 조직, 병리학적인 검사에서는 모든 투여구간에 커다란 차이가 없었다.

• Reproductive and Developmental Biology
• /
• v.30 no.2
• /
• pp.143-156
• /
• 2006

Major characteristics of embryonic stem cells (ESCs) are sustaining of sternness and pluripotency by self-renewal. In this report, transcriptional profiles of the molecules in the developmentally important signaling pathways including Wnt, BMP4, $TGF-\beta$, RTK, Hh, Notch, and JAK/STAT signaling pathways were investigated to understand the self-renewal of mouse ESCs (mESCs), J1 line, and compared with the NIH3T3 cell line and mouse embryonic fibroblast (MEF) cells as controls. In the Wnt signaling pathway, the expression of Wnt3 was seen widely in mESCs, suggesting that the ligand may be an important regulator for self-renewal in mESCs. In the Hh signaling pathway, the expression of Gli and N-myc were observed extensively in mESCs, whereas the expression levels of in a Shh was low, suggesting that intracellular molecules may be essential for the self-renewal of mESCs. IGF-I, IGF-II, IGF-IR and IGF-IIR of RTK signaling showed a lower expression in mESCs, these molecules related to embryo development may be restrained in mESCs. The expression levels of the Delta and HESS in Notch signaling were enriched in mESCs. The expression of the molecules related to BMP and JAK-STAT signaling pathways were similar or at a slightly lower level in mESCs compared to those in MEF and NIH3T3 cells. It is suggested that the observed differences in gene expression profiles among the signaling pathways may contribute to the self-renewal and differentiation of mESCs in a signaling-specific manner.

• Analytical Science and Technology
• /
• v.31 no.5
• /
• pp.185-194
• /
• 2018

At the end of November 2010, livestock infected with foot and mouth disease (FMD) were buried, increasing concern about secondary pollution of drinking water and groundwater with odor. Hence, measures to reduce pollution of drinking water and groundwater are needed. In this study, based on livestock type and soil texture, five pilot-scale burial sites were monitored for the past three years from Feb 2012 to 2015. Leachate from the site was analyzed for 90 compounds. A detailed investigation has been completed, looking into organic matter decomposition characteristics of the buried bodies, relevant trace elements thereof, and in particular metabolite concentration changes such as the degree of decomposition of a carcass. From the results, no detectable heavy metals, including cadmium and arsenic, were measured. Among animal types, the rate of cattle decomposition is faster than swine decomposition, and the decomposition of the bodies were performed in sequence from sand, clay loam, sandy loam.

• Journal of Bio-Environment Control
• /
• v.15 no.3
• /
• pp.283-288
• /
• 2006

Characteristics of the rootstock formation and flower bud differentiation according to sowing time for production of the high quality rootstock in Chicory (Cichorium intybus L.) was investigated. The flower bud initiation was on the 17th of July after sowing in April, the 2nd of July after sowing in May, the 30th of July after sowing in June and the 1st of October after sowing in July. But they didn't differentiate after sowing in August and September. The days required from germination to flower bud initiation and accumulated temperature depended on the weather. If the outside air temperature was high, the days required were less, If the outside air temperature was low, the days required were greater, the accumulated temperature was similar to the days required in this experement, too. The rootstock sown from April to July wasn't good enough to be use because the flower bud differentiation was generated before harvestable weight. the weight of rootstock was sown in September wasn't heavy enough in weight because the outside air temperature was too low for it to grow well. The plant grows slow and steady through out winter. The rootstock sown in August was havestable 200g in 90 days after sowing before the flower bud differentiated. The best sowing time for the production of high quality rootstock of Chico in the climate of Korea is researched to be August.