• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.2
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• pp.67-75
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• 2002

The human complement receptor type 1 (CR 1, C3 b/C4b receptor) is a polymorphic membrane glycoprotein expressed on human erythrocytes, peripheral leukocytes, plasma and renal glomerular podocytes, which consists of transmembrane and cytoplasmic domains with 30 repeating homologous protein domains known as short consensus repeats (SCR). CR1 has been used as an inhibitor for inflammatory and immune system for the past several years. Recently; it is reported that CRl was found to suppress the hyper-acute rejection in xeno-transplantation and can be used to cure autoimmune diseases. A soluble form of CRl, called sCRl, is a recombinant CRl by cleaving the transmembrane domain at C-terminus and has been expressed in Chinese Hamster Ovary (CHO) cells. Several purification methods for sCR1 from CHO cells have been reported, but most of them require complicated steps at high cost. Moreover, such methods are mostly performed under the pH condition apt to denaturing sCR1 and causes sCRl losing its activity. We here report a rapid and efficient method to purify sCR1 from CHO cell. The new method consists of a two-stage of cell culture by cultivating cells in serum medium followed by serum-free medium, and a two-stage of column purification by means of heparin and gel filtration column chromatography. By using this novel method, sCR1 can be purified in a simple and effective way with high yield and purity, furthermore, the purified sCR1 was confirmed to retain its activity to suppress the complement activation in vivo and ex vivo.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.362-367
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• 1998

Thyroid hormone(T3) stimulates hepatic lipogenesis by increasing expression of genes, indluding acetyl-CoA carboxylase and fatty acid synthase. S14 protein, which is thougth to be involved in lipid metabolism , appears to respond in parallel . Effect of T3 on lipogenesis in white and brown adipose tissue are less clear, and may be complicated by indirect effects of the hormone. We developed an adipocytes system where the indirect effects of thyroid hormone are abolished and direct effects of T3 on lipogenesis could be tested. Fat accumulation was mesured by Oil-Red O staining. Insulin clearly enhanced fat accumulation by 2-fold . Isobutylemethylxanthie(IBMX) apeared to inhibit insulin -stimulated fat accumulation. Dexamethasone increased insulin-stimulatedfat accumulation about 1.3-fold. confluent adipocytes were cultured in serum-free medium or medium containing 10% fetal calf serum or 10% fetal calf serum stripped of thyroid hormone and lipogenesis, assessed by the incorporation of 3H2O , was measured. Medium without serum or supplemented with T3-depleted serum did not amplify the stimulatory effect of T3 on lipogenesis compared to medium containing 10% fetal calf seru. Dexamethasone alone led to a decrease inlopogenesis of about 50 % in white adipocytes and 25% in brown adipocytes. However, dexamethasone amplified the lipogenic respnse to T3 by about 30% in whit eadipocytes and 60% in brown adipocytes. T3(1$\mu$M) stimulated lipogenesis and acetyl-CoA carboxylase and fatty acid syntase mRNA levels up to 2 -fold in both types of adipocytes. It seems that these adipocytes systems are as useful model to study the effects of hormones on lipogenic gene expression as well as lipogenesis.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.712-720
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• 2007

To investigate clonal variations of recombinant Chinese hamster ovary(rCHO) clones in response to culture pH and temperature, serum-free suspension cultures of two antibody-producing CHO clones(clones A and B), which were isolated from the same parental clone by the limiting dilution method, were performed in a bioreactor at pH values in the range of 6.8-7.6, and two different temperatures, $33^{\circ}C\;and\;37^{\circ}C$. In regard to cell growth, clone A and clone B displayed similar responses to temperature, although their degree of response differed. In contrast, clones A and B displayed different responses to temperature in regard to antibody production. In the case of clone A, no significant increase in maximum antibody concentration was achieved by lowering the culture temperature. The maximum antibody concentration obtained at $33^{\circ}C$(pH 7.4) and $37^{\circ}C$(pH 7.0) were $82.0{\pm}2.6$ and $73.2{\pm}4.1{\mu}g/ml$, respectively. On the other hand, in the case of clone B, an approximately 2.5-fold increase in maximum antibody concentration was achieved by lowering the culture temperature. The enhanced maximum antibody concentration of clone B at $33^{\circ}C$($132.6{\pm}14.9{\mu}g/ml$ at pH 7.2) was due to not only enhanced specific antibody productivity but also to prolonged culture longevity. At $33^{\circ}C$, the culture longevity of clone A also improved, but not as much as that of clone B. Taken together, CHO clones derived from the same parental clone displayed quite different responses to culture temperature and pH with regards antibody production, suggesting that environmental parameters such as temperature and pH should be optimized for each CHO clone.

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.58-64
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• 2006

We successfully isolated human anagen hair follicles from human scalp skin by microdissection and tried to culture them under various conditions. First we confirmed negative effect of serum on human hair follicle organ culture. As a next step serum-free medium compositions, Philpott medium, IMDM, and DHGM (Dongguk hair growth medium) were tried. Philpott medium is a general medium for hair organ culture based on Williams' E medium and DHGM is a special self-developed medium containing high amino acids and vitamins (B group) composition. As results, hair follicle in Philpott medium and IMDM showed anagen phase morphological structure, but rapid loss of hair elongation, low alkaline phosphatase expression, and very low expression of CK19. It is thought these hair follicles rapidly regressed from apoptosis. However, hair follicles in DHGM showed long term anagen phase morphological structure, continuous hair elongation, high alkaline phosphatase, and CK19 expression. These results demonstrate that high amino acids and vitamins (B group) composition are essential to in vitro long term human hair follicle organ culture and this culture medium will be useful in basic study of hair biology or application study to the development of alopecia treatment drugs.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.181-186
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• 2005

This experiment was conducted to investigate effects of the two different in vitro production systems, serumcontaining system (IVM, IVF and IVC; TCM199, TALP and CR1aa) and serum-free system (IVM, IVF and IVC; IVMD101, IVMD100 and IVMD101), on the development of in vitro fertilized or DNA-microiniected embryos. We also examined the effect of DNA dosage and its expression pattern in embryos. The DNA used for microinjection was a green fluorescence protein gene. The development rates to $\geq$ 2cell, 8cell and blastocyst stage were significantly higher in vitro fertilized embryos than those in DNA-microinjected embryos. The development rate to the 8-cell stage was significantly higher in serum-free system than in serum-containing system (p<0.05; $3.3\%\;vs.\;15.5\%\;and\;21.4\%$, respectively). The development rates to the blastocyst stage of in vitro fertilzed or DNA-microinjected embryos between two different culture system ($2.7\%\;vs.\;2.3\%\;and\;23.0\%\;vs.\;23.6\%$, respectively) were not different. The development rates of embryos injected 2 ng/uL DNA was higher. than those of embryos injected 4 or 8 ng/uL DNA. The GFP expression rate of 1-cell embryos was significantly higher than that of 2-cell and 4-cell embryos, whereas the rates were not different between 4-cell and blastocyst-stage embryos.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1557-1563
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• 2005

Ovarian follicular fluid contains both stimulatory and inhibitory agents that influence the growth and maturation of oocyte. In the present study, an attempt was made to isolate and study the biological properties of ovarian follicular fluid peptide(s) in buffaloes. Bubaline ovarian follicular was made steroid- and cell-free. A protein fraction was obtained by saturation (30-35% level) of the follicular fluid with ammonium sulfate. The protein fraction was purified with Sephadex-G 50 gel filtration chromatography and a single peak was obtained in the eluant volume, which was lyophilized. SDS-PAGE of the lyophilized fraction revealed a single band and the molecular weight of the peptide was 26.6 kDa. The peptide stimulated the cumulus cell expansion and in vitro maturation rate of oocytes in buffaloes in a dose dependent manner when it was incorporated at different dose levels (0, 10, 25, 50, 100 and 1,000 ng $ml^{-1}$ of maturation medium). The basic culture medium consisted of TCM 199 with Bovine serum albumin (0.3%). The in vitro maturation rates were comparable to those obtained with a positive control medium (TCM 199+20 ng EGF $ml^{-1}$+steer serum (20%)). Further purification and biological assays may throw more light on the nature and functions of this peptide.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1562-1570
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• 2014

The effects of Lactobacillus mucosae (L. mucosae), a potential direct fed microbial previously isolated from the rumen of Korean native goat, on the rumen fermentation profile of brewers grain were evaluated. Fermentation was conducted in serum bottles each containing 1% dry matter (DM) of the test substrate and either no L. mucosae (control), 1% 24 h broth culture of L. mucosae (T1), or 1% inoculation with the cell-free culture supernatant (T2). Each serum bottle was filled anaerobically with 100 mL of buffered rumen fluid and sealed prior to incubation for 0, 6, 12, 24, and 48 h from which fermentation parameters were monitored and the microbial diversity was evaluated. The results revealed that T1 had higher total gas production (65.00 mL) than the control (61.33 mL) and T2 (62.00 mL) (p<0.05) at 48 h. Consequently, T1 had significantly lower pH values (p<0.05) than the other groups at 48 h. Ammonia nitrogen ($NH_3$-N), individual and total volatile fatty acids (VFA) concentration and acetate:propionate ratio were higher in T1 and T2 than the control, but T1 and T2 were comparable for these parameters. Total methane ($CH_4$) production and carbon dioxide ($CO_2$) were highest in T1. The percent DM and organic matter digestibilities were comparable between all groups at all times of incubation. The total bacterial population was significantly higher in T1 (p<0.05) at 24 h, but then decreased to levels comparable to the control and T2 at 48 h. The denaturing gradient gel electrophoresis profile of the total bacterial 16s rRNA showed higher similarity between T1 and T2 at 24 h and between the control and T1 at 48 h. Overall, these results suggest that addition of L. mucosae and cell-free supernatant during the in vitro fermentation of dried brewers grain increases the VFA production, but has no effect on digestibility. The addition of L. mucosae can also increase the total bacterial population, but has no significant effect on the total microbial diversity. However, inoculation of the bacterium may increase $CH_4$ and $CO_2$ in vitro.

• Journal of Aquaculture
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• v.6 no.2
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• pp.107-123
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• 1993

To define the effects of various levels $(0\~1.5\%)$ of dietary n-3HUFA on the physiological changes in the Korean rockfish, variations in blood variables and hepatocytes were studied. Biochemical serum analyses, lactate dehydrogenase (LDH) activity of the liver cytosol and ATPase activity of the liver microsomal membrane were also studied. The haematological values (red blood cell, hemoglobin, hematocrit, MCHC, MCV and MCH) were not significantly different in the experimental groups $(P\geq0.05)$. The total protein and glucose levels in the serum were affected by dietary n-3HUFA levels. These levels in groups fed n-3HUFA insufficient diets were significantly lower than those of n-3HUFA sufficient groups (P<0.05). Serum levels of total cholesterol, free cholesterol, glutamic pyruvic transaminase (GPT) and glutamic oxaloacetatic transaminase (GOT) showed significantly higher values in the fish fed n-3HUFA deficient diets (P<0.05). The LDH in the serum was dropped with increasing dietary n-3HUFA levels, but the LDH activity of the liver cytosol was elevated. Histologically, the hepatic cell in the fish fed n-3HUFA free diet was abnormal and showed a necrotic condition. $Ca^{2+}-ATPase$ activities of the liver microsomal membrane were significantly lower in the fish fed n-3HUFA deficient diets than in those fed n-3HUFA sufficient diets (p<0.005). These results suggested that the liver cell membrane was affected by dietary fatty acid compositions and cell membrane of the fish fed n-3HUFA insufficient diets showed abnormalities.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.3
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• pp.163-170
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• 2002

This report describes the use of a transtubular bioreactor to study the relative effects of diffusion versus perfusion of medium on antibody production by a hybridoma cell line. The study was performed with a high-density cell culture maintained in a serum-free, low-protein medium for 77 days. It was determined that the reactor possessed a macro-mixing pattern residence time distribution similar to a continuous stirred tank reactor (CSTR), However, due to the arrangement of the medium lines in the reactor, the flow patterns for nutrient distribution consist of largely independent medium path lengths ranging from short to long. When operated with cyclic, reversing, transtubular medium flow, some regions of the reactor (with short residence times) are more accessible to medium than others (with long residence times). From this standpoint, the reactor can be divided into three regions: a captive volume, which consists of medium primarily delivered via diffusion; a lapped volume, which provides nutrients through unilateral convection; and a swept volume, which operates through bilateral convection. The relative sizes of these three volumes were modified experimentally by changing the period over which the direction of medium flow was reversed from 15 min (larger captive volume) to 9 h (larger swept volume). The results suggest that antibody concentration increases as the size of the diffusion-limited (captive) volume is increased to a maximum at around 30 min with a sharp decrease thereafter. As reflected by changes in measured consumption of glucose and production of lactate, no significant difference in cellular metabolism occurred as the reactor was moved between these different states. These results indicate that the mode of operation of the transtubular bioreactor may influence antibody productivity under serum-free, low-protein conditions with minimal effects on cellular metabolism.

• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.220-226
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• 1996

To investigate the effect of long chain n-3 polyunsaturated fatty acids on breast cancer cell growth, estrogen-dependent MCF-7 human breast cancer cells were cultured serum-free DMEM media containing 0.5$\mu\textrm{g}$/ml of differnet kinds of fatty acids; linoleic acid(LA), arachidonic acid(AA), eicosapentaenoic acid(EPA) and docosahexaenoic acid acid(DHA) and 1, 0.1, 0.2, 0.5and 1.0ng/ml 17$\beta$-estradiol as well as 10$\mu\textrm{g}$/mi insulin and 1.25 mg/ml delipidized bovine serum albumin for 3 days. Cell growth monitored by MTT assay was lower in DHA and EPA treatments as compared to LA treatment, but not with AA treatment. Estrogen concentrations at which cell growth was initially stimulated were 0.1ng/ml for LA and DHA treatments and 0.2ng/ml for EPA and AA treatments, but the degree of stimulation was 25~30% lower in DHA and EPA treatments than in LA treatment. Fatty acid analysis showed that each fatty acid in culture medium was well incoporated into celluar lipid. Protein kinase C activity of cells was most elevated in LA treatment from 2 to 8 hours of culture followed by DHA, EPA, and AA treatments. It is concluded that inhibitions of n-3 DHA and EPA on breast cancer cell growth as compard with n-6 LA is mediated via changes in membrane fatty acid composition reducing estrogen sensitivity and increasing protein kinase C activity.