• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.487-493
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• 2018

Cluster of differentiation 44 (CD44), a cell surface receptor for hyaluronic acid (HA), is involved in aggressive cancer phenotypes. Herein, we investigated the role of the CD44 standard isoform (CD44s) in hypoxia-inducible $factor-1{\alpha}$ ($HIF-1{\alpha}$) regulation using MCF7 overexpressing CD44s (pCD44s-MCF7). When pCD44s-MCF7 was incubated under hypoxia, levels of $HIF-1{\alpha}$, vascular endothelial growth factor, and the $HIF-1{\alpha}$ response element-derived luciferase activity were significantly increased compared to those in the control MCF7. Incubation of pCD44s-MCF7 cells with HA further increased $HIF-1{\alpha}$ accumulation, and the silencing of CD44s attenuated $HIF-1{\alpha}$ elevation, which verifies the role of CD44s in $HIF-1{\alpha}$ regulation. In addition, the levels of phosphorylated extracellular signal-regulated kinase (ERK) was higher in hypoxic pCD44s-MCF7 cells, and $HIF-1{\alpha}$ accumulation was diminished by the pharmacological inhibitors of ERK. CD44s-mediated $HIF-1{\alpha}$ augmentation resulted in two functional outcomes. First, pCD44s-MCF7 cells showed facilitated cell motility under hypoxia via the upregulation of proteins associated with epithelial-mesenchymal transition, such as SNAIL1 and ZEB1. Second, pCD44s-MCF7 cells exhibited higher levels of glycolytic proteins, such as glucose transporter-1, and produced higher levels of lactate under hypoxa. As a consequence of the enhanced glycolytic adaptation to hypoxia, pCD44s-MCF7 cells exhibited a higher rate of cell survival under hypoxia than that of the control MCF7, and glucose deprivation abolished these differential responses of the two cell lines. Taken together, these results suggest that CD44s activates hypoxia-inducible $HIF-1{\alpha}$ signaling via ERK pathway, and the $CD44s-ERK-HIF-1{\alpha}$ pathway is involved in facilitated cancer cell viability and motility under hypoxic conditions.

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.289-293
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• 1998

We investigated the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in methanol extracts of 64 cultured cell lines, which were derived from various plant species, and the ascorbate content in cell lines, which showed a high radical scavenging activity. Thirteen cell lines revealed the antioxidative activity ($IC_{50}$) by methanol extracts of less than 50 mg in cell fresh wt. Of them, six cell lines showed the same Rf value as ascorbate on the DPPH sprayed silica gel TLC. The ascorbate content in cell lines of Rosa multiflora, Scutellaria baicalensis, and Achyranthes japonica showed 48.5, 30.3, and $16.8\;\mu\textrm{g}$ per g cell fresh wt by HPLC analysis, respectively. In callus cultures of S. baicalensis, the concentration of ascorbate reached a maximun ($39{\pm}3.4\;\mu\textrm{g}/g$ cell fresh wt) on 30 days after subculture, which corresponded to the stationary growth phase, and subsequently decreased by successive culturing.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.411-419
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• 2003

The potent biosynthetic precursors, 24$\alpha$-methylcholesterol and 24$\alpha$-methylcholestanol, and the endogenous brassinosteroids (BRs), castasterone (CS) and 6-deoxocastasterone (6-deoxoCS), were identified from shoots of maize seedlings. In addition, the presence for activities of several enzymes involved in the late C6-oxida-lion pathway from 24$\alpha$-methylcholestanol to CS was demonstrated in the plants. However, activity for brassinolide (BL) synthase which catalyze the conversion of CS to BL, the last step of the late C6-oxidation pathway, was not detected in the enzyme solution obtained from the maize shoots. Together with the fact that BL was not identified from the maize shoots, these results strongly suggested that BRs in the maize shoots are biosynthesized during seedling growth and the active BR in the shoots is not BL but CS.

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.295-299
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• 1998

To detect the effects of gelling agent brands and concentration on rice anther culture, anthers of rice(O. sativa L. japonica, cv, Nagdongbyeo) were inoculated on N6-Y1 basic media supplemented with 0.4~1.6% Bacto agar(Difco, 04140-01), Agarose(Sigma, Type 1) and 0.2~0.8% Gelrite(Kelco, 143364) as gelling agents. On 0.4% Bacto agar and Agarose media, the frequency of callus formation which was significantly decreased in proportion to gelling agent's concentration was 39% and 55%, respectively. On 0.6% Gelrite media, the frequency of callus formation which was not statistically significant among the 0.2~0.8% concentration was 44%. Calli derived from the higher concentration of gelling agents showed embryogenic with slow growth, small, whitish and hard shape compare to that of the lower concentration. The frequency of green plant regeneration was high not only in calli derived from the higher concentration but also in plant regeneration medium with the higher concentration after callus transfer. Calli derived from the higher concentration was effective to maintain the frequency of green plant regeneration up to 60 days after anther inoculation. Introduction of 0.6~0.8% Geltite for callus formation, then transferred 1.6% Bacto agar and Agarose or 0.8% Gelrite for green plant regeneration was effective to increase anther culture efficiency.

• Journal of Plant Biotechnology
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• v.37 no.1
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• pp.102-109
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• 2010

Fructan has been found to accumulate in various tissues during periods when light levels increased carbon fixation where low temperatures reduced growth rates while photosynthesis continued. In this study, we have cloned 1-sucrose:sucrose fructosyl transferase(1-sst) and 1-fructan: fructan fructosyl transferase (1-fft, a key enzyme for the synthesis of fuctan) from Jerusalem Artichoke (Helianthus tuberosus L.). The recombinant vector with 1-sst and 1-fft has been constructed under the control of 35S promoter of KJGV-B2 vector and transgenic plants obtained by Agrobacterium tumefaciens LBA4404. PCR analysis carried out on the putative transgenic plants for amplification of the coding region of specific gene (1-sst, 1-fft), and HPT genes. Transgenic lines carrying of 1-sst and 1-fft were confirmed for integration into the rice genome using Southern blot hybridization and RT-PCR. The transgenic plants in $T_2$ generation were selected and expression pattern analysis revealed that 1-sst and 1-fft were stable. This analysis confirmed the presence of low-molecular-weight fructan in the seedling of the transgenic rices. Therefore, cold tolerance and carbohydrate metabolism will be possible to develop resistant plants using the transgenic rice.

• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.141-146
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• 2013

This study was conducted to examine suspended embryogenic cells growth with days of culture, effects of various kinds/concentrations of osmoticum for induction of somatic embryos (SEs), following somatic embryos germination or plantlet regeneration. The proliferation pattern of embryogenic cells in suspension culture is characterized by settled cells volume (SCV) increased with the duration of culture with marked the maxium of SCV (10.1 ml) in 18 days of culture, however the SCV of cells gradually decreased after that. In comparison of kinds/concentrations of osmoticum on somatic embryo induction, the highest induction number (352.3/g FW) of the SE was showed in 0.2 M sucrose, in addition, we also observed some effects with treatments of 0.2 M maltose (203.7) and 0.3 M maltose (193.7), respectively. However, no somatic embryos produced in treatments of 7.5% PEG plus 0.15 M sucrose or maltose. In comparison of germination efficiency of SEs which occurred from the treatments of various kinds/ concentrations of osmoticum, the highest induction frequency of cotyledon (25.2%) was obtained from SEs that produced 0.3 M maltose, however, the best occurrence rates of hypocotyl (39%), radicle (30.3%) and plantlet regeneration (3.5%) were observed from the 0.2 M sucrose treatment, respectively.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.173-186
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• 2000

This experiment was carried out to investigate the tendency of incident diseases in pre- and post- weaning piglets which ages were 1 to 7 weeks old by laboratory diagnosis and in order to minimize death in preweaning piglets and of stunted growth in postweaning piglets. The result of this experiment used as the basic data for the preventive programs in pre- and post- weaning piglets and were as follows: 23 different diseases diagnosed in 331 cases were studied in relation to age, season, and etiology. The most prevelent diseases of pre- and post- weaning piglet were Colibacillosis(79 case, 23.9%) and the major diseases were Salmonellosis(44 cases, 13.3%), Anemia(37 cases, 11.2%). Unknown viral disease(20 case, 6.1%), Rota viral infection(19 case, 5.8%), Porcine reproductive & respiratory syndrome(PRRS; 15 case 4.5%), Transmissible gastroenteritis(TGE; 12 case, 3.6%). The gastrointestinal disease, such as Colibacillosis, Salmonellosis, Swine dysentery, Clostridial infection, Rotaviral infection, TGE, Porcine epidemic diarrhea(PED) and Ballantidiosis occured pro- dominently in the period of pre- and post- weaning, which were 178 cases(53.8%) and not related to occurrence according to age and season. The respiratory diseases were Atrophic rhinitis(AR), Swine enzootic pneumonia, Pneumonic pasteurellosis, Pleuropneumonia, Branchopneumonia, PRRS and which were 48 cases(14.5%) and higher prevalent in spring and summer. The viral diseases was 73 cases(22.1%) that occurred in the period of 5 weeks piglet and prevalent mainly in spring. The bacterial diseases were 188 cases(56.8%) that were not related to occurrence according to age and season. Salmonellosis was prevalent in 3 to 5 weeks piglet and mainly occurred in summer. Viral septicemia and rotaviral infection occurred after 5 weeks piglets intensively and 3 to 5 weeks, respectively. And the both occurred without relation with season. PRRS occurred after 4 weeks piglet and prevalent in summer. TGE occurred 1 to 7 days old piglets and prevalent in spring and winter. Hematologic values of anemia was decrease in number of Red Blood Cell, concentration of Hemoglobin and Hematocrit. Amikacin, cephalothin, colistin, norfloxacin were effective to E coli, and amikacin, cephalothin, nortloxacin, neomycin were effective to Salmonellra spp. but clindamycin, erythromycin, penicillin, sulfonamides were resistant to E coli and Salmonella spp.

• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.247-256
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• 1999

A disease of young Holstein calves characterized by recurrent pneumonia, ulcerative and granulomatous stomatitis, enteritis with bacterial overgrowth, periodontitis, delayed wound healing, persistent neutrophilia and death at an early age had been originally described in 1983 and again in 1987. Most of these calves had stunted growth and a persistent, progressive neutrophilia (often exceeding 100,000/ml). By investigation of pedigrees, all of the affected calves have now been traced to a common sire and confirmed by polymerase chain reaction (PCR) diagnostic DNA testing to be homozygous carriers of a defective allele for bovine CD18. Neutrophils from these calves have several functional deficits and, most importantly, fail to adhere in a ${\beta}_2$-integrin dependent manner. The ${\beta}_2$-integrins represent a family of glycoproteins which participate in various leukocyte adhesion reactions during host defense. The presence or absence of ${\beta}_2$-integrin molecules can be demonstrated on the surface of neutrophils, monocytes and lymphocytes from normal or affected calves using specific monoclonal antibodies and flow cytometry, or by colloidal gold immunolabeling and scanning electron microscopy in backscatter mode. Deficiency of the ${\beta}_2$-integrins on all leukocyte types in Holstein calves is analogous to leukocyte adhesion deficiency (LAD) seen in humans. Neutrophils in bovine (BLAD) and human LAD patients are unable to adhere to the endothelial lining of the cardiovascular system thus interrupting egression of neutrophils into infected tissues. Other leukocytes, while still deficient in expression of the ${\beta}_2$-integrins, are still able to efficiently egress from the blood stream due to interactions of other adhesion molecules that are not as highly expressed on neutrophils. Both BLAD cattle and LAD children (who do not receive bone marrow transplants) often die at an early age as a result of the failure of neutrophils to extravasate into infected tissues. In 1991, Shuster, et $al^{27}$, identified two point mutations within the alleles encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency. One mutation causes an aspartic acid to glycine substitution at amino acid 128 (D128G) in an extracellular region of this adhesion glycoprotein that is highly conserved (> 95% identity) between humans, cattle and mice. The other mutation is silent. Numerous calves with clinical symptoms of leukocyte adhesion deficiency have since been tested and all have been found homozygous for the D128G allele. In addition, calves homozygous far the D128G allele have been identified during widespread DNA testing in the United States. All cattle with the mutant allele are related to one bull, who through artificial insemination (A.I.), sired many calves in the 1950's and 1960's. The carrier frequency of the D128G CD18 allele among U.S. Holstein cattle had reached approximately 15% among active A.I. bulls and 8% among cows. By 1993, the organization of the dairy industry and the diagnostic test developed to genotype cattle, enabled virtually complete eradication of bovine leukocyte adhesion deficiency among current and future A.I. bulls.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.247-254
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• 1996

Serial ultrasonographic examinations were performed on 9 pregnant Korea Jin-do dog from days 15 to 60 to determine the size of gestational structures throughout pregnancy. Gestational age was timed from the day of ovulation (Day 0), which was estimated to occur when plasma progesterone concentration was first increased above 4.0 ng/ml. Extra-fetal structures were measureable from days 17 to 49. Outer uterine diameter increased from $7.0{\pm}0.7$ ($mean{\pm}SD$)mm at day 17 to $54.0{\pm}2.2mm$ at day 49 and inner chorionic cavity diameter increased from $3.0{\pm}0.7mm$ at day 17 to $37.5{\pm}0.6mm$ at day 49. Uterine wall thickness increased from $2.8{\pm}0.4mm$ at day 17 to $8.3{\pm}0.5mm$ at day 49, placental thickness increased from $1.0{\pm}0.1mm$ at day 22 to $5.7{\pm}0.2mm$ at day 49 and length of chorionic cavity or zonary placenta increased from $5.5{\pm}1.3mm$ at day 20 to $52.3{\pm}2.2mm$ at day 49. Inner chorionic cavity diameter, outer uterine diameter and placental length each increased at a linear rate through day 37, after which time, each had a marked plateau in growth. Of the extra-fetal structures, inner chorionic cavity diameter was the most accurate for estimation of gestational age until day 37. Fetal structures were measureable from days l7 to 60. Crown-rump length, increased from $3.0{\pm}0.7mm$ at day 22 to $118.7{\pm}3.1mm$ at day 49, fetal body diameter increased from $4.0{\pm}0.7mm$ at day 25 to $55.8{\pm}1.7mm$ at day 60 and fetal head diameter increased from $4.3{\pm}0.6mm$ at day 26 to $29.8{\pm}0.8mm$ at day 60. Of the fetal structures, fetal head diameter was the most accurate for estimation of gestational age from day 37 until day 60.

• Korean Journal of Veterinary Research
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• v.35 no.1
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• pp.187-195
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• 1995

The present study carried out to determine the developmental capacity of bovine oocytes matured in epidermal growth factor(EGF)-containing medium, the developmental competence of bovine embryos using synthetic oviduct fluid(SOF) and the effect of glucose on the development of bovine embryos. In experiment 1, oocytes, obtained from abattoir ovaries, were matured in EGF-containing medium for 24 hours, followed by exposure to Korean native cattle spermatozoa for 18 hours and cultured by utilizing co-culture system with bovine oviduct epithelial cells(BOEC) in TCM199. In experiment 2, early bovine embryos were cultured in SOF with or without BOEC and compared with those in TCM199 with BOEC. In experiment 3, bovine embryos were cultured in the presence or absence of glucose. Seven and ten days after in vitro fertilization, developmental competence of embryos were evaluated. The rate of cleavage was significantly(P<0.05) higher in EGF-containing maturation medium(70.0%) than in control(57.7%). The rates of development to morulae and blastocysts were 30.6% and 23.3% there was no significant difference between them. The rates of in vitro fertilized embryos to morulae and blastocysts cultured in SOF with BOEC(30.4%) and in TCM199 with BOEC(38.0%) were significantly(P<0.01) higher than cultured in SOF without BOEC(13.4%) at seven days after in vitro fertilization. The rates of embryos to blastocysts cultured in SOF with BOEC(29.4%) and in TCM199 with BOEC(35.9%) were significantly(P<0.05) higher than cultured in SOF without BOEC(13.4%) at ten days after in vitro fertilization. The rates of early embryos to morulae and blastocysts cultured in the presence or absence of glucose were 12.2% and 17.5% each other, there was no significant difference between them. The results show that bovine oocytes matured in the presence of EGF can cleave better, SOF with BOEC can replace serum containing complex media, TCM199 with BOEC in bovine embryo culture and glucose have little effect on the culture of early bovine embryos.