• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1411-1416
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• 2004

The objective of this work was to isolate a microorganism, able to produce high lactate dehydrogenase (LDH) activity, for use as a microbial feed additive. The LDH is an important enzyme for lactate conversion in the rumen, thereby possibly overcoming lactic acidosis owing to sudden increases of cereal in the diets of ruminants. In the present study, various bacterial strains were screened from a variety of environments. Among the isolated microorganisms, strain FFy 111-1 isolated from a Korean traditional fermented vegetable food called Kimchi showed the highest enzyme activity, along with retaining strong enzyme activity even in rumen fluid in vitro. Based on morphological and biochemical characteristics as well as compositions of cellular fatty acids plus API analyses, this strain was identified as Lactobacillus sp. The optimum temperature and pH for growth were found to be 30$^{\circ}C$ and pH 6.5, respectively. A maximum cell growth of 2.2 at $A_{650}$ together with LDH activity of 2.08 U per mL was achieved after 24 h of incubation. Initial characterization of FFy 111-1 suggested that it could be a potential candidate for use as a direct-fed microbial in the ruminant animals.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4295-4299
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• 2013

Background: Pretreatment serum p53 and epidermal growth factor receptor (EGFR) were assessed using enzyme-linked immunosorbent assay (ELISA) in patients with acute leukemia to analysis their roles in characterization of different subtypes of the disease. Materials and Methods: Serum samples from thirty two patients with acute myeloid leukemia (AML) and fourteen patients with acute lymphoid leukemia (ALL) were analysed, along with 24 from healthy individuals used as a control group. Results: The results demonstrated a significant increase of serum p53 and EGFR in patients with AML (p<0.0001) compared to the control group. Also, the results showed a significant increase of both markers in patients with ALL (p<0.05, p<0.0001 respectively). Sensitivities and specificities for these variables were 52% and 100% for p53, and 73.9%, 95.8% for EGFR. Serum p53 and EGFR could successfully differentiate between M4 and other AML subtypes, while these variables failed to discriminate among ALL subtypes. A positive significant correlation was noted between p53 and EGFR. Negative significant correlations were observed between these variables and both of hemoglobin (Hg) content and RBC count. Conclusions: Mutant p53 and EGFR are helpful serological markers for diagnosis of patients with AML or ALL and can aid in characterization of disease. Moreover, these markers may reflect carcinogenesis mechanisms.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.55-55
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• 2002

Occurrences of diseased sweet flag (Acorus calamus L. var. asiaticus) were found in Chonju and Buan Province, on August 2002. The typical symptoms of the disease affected the leaves, pods, and collar of the infected plants. The leaves or pods became darker brown, then dry rotted, and white fluffy mycelia formed on the lesion. The collar, of the infected plants, formed black spot. The spores grew rapidly on PDA medium. Pathogenic fungi have not been identified clearly, as of yet. These fungi were formed from developed spores, as well as, undeveloped spores. These fungi suggest that Fusarium sp. and Rhizoctonia sp.. The range of temperatures were tested from 5$^{\circ}C$ to 35$^{\circ}C$ for mycelial growth. The optimum temperature for growth was 3$0^{\circ}C$. This is the first report on the fungus disease of sweet flag by some pathogens, in Korea. We would like to do further research for single spore isolation, pathogenity, and characterization of fungi.

• JSTS:Journal of Semiconductor Technology and Science
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• v.6 no.2
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• pp.90-94
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• 2006

We report on the growth and characterization of InGaN/GaN MQWs on two different types of sapphire substrates and GaN substrates. The InGaN/GaN MQWs are grown by using metalorganic chemical vapor deposition. Our analysis of the satellite peaks in the HRXRD patterns shows, GaN substrates InGaN/GaN MQW compared to sapphire substrates InGaN/GaN MQW, more compressive strain on GaN substrates than on sapphire substrates. However, results of optical investigation of InGaN/GaN MQWs grown on GaN substrates and on sapphire substrates, which have lower Stokes-like shift of PL to GaN substrates compared to sapphire substrates, are shown to the potential fluctuation and the quantum-confined Stark effect induced by the built-in internal field due to spontaneous and straininduced piezoelectric polarizations. The InGaN/GaN MQWs are shown to quantify the Stokes-like shift as a function of x.

• Journal of Microbiology
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• v.34 no.4
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• pp.327-333
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• 1996

Yeast, like many other microbes, encounters large variations in ambient pH in their natural environments. Microorganisms capable of growing over a wide pH range require a versatile, efficient pH homeostatic mechanism protecting intracellular processes against extremes of pH. In several organisms, fusions to the bacterial lacZ gene have been extremely useful for the identification of genes expressed at different time during the life cycle or under different growth conditions. In this study, using the lacZ gene screening system, we surveyed a large number of yeast strains with lacZ insertion to identify genes regulated by pH. A yeast genomic library was constructed and inserted with lacZ by a shuttle mutagenesis procedure. The yeast transformants were individually picked up with a toothpick, replica-plated, and grown in alkaline pH medium. Among the 35,000 colonies screened, 10 candidate strains were identified initially by the $\beta$-gal assay. We finally confirmed two yeast strains carrying the genes whose expression are strictly dependent on pH of growth medium. One of the fusions showing a 10-fold induction in expression level in response to alkali pH was selected and further characterized. The pH-regulated gene was cloned by inverse PCR and a partial sequence of the gene was determined. Identification and characterization of the gene is currently under investigation.

• Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.177-185
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• 2013

The development of species-specific fish cell lines has become a valuable tool for biological research. In recent years, marine medaka Oryzias dancena has been recognized as a good experimental model fish but there are no reports of establishment of cell lines from this fish. In this study, two cell lines from O. dancena blastula embryos were established from 41 total trials (4.9%). The two cell lines displayed typical in vitro morphology and have been cultured for >121 passages, which corresponds to 293 days. The doubling times of the cell lines were 29.84 and 28.59 h, respectively, and both possessed the potential to expand in a clonal manner, albeit with significant differences between the two cell lines. The absence of any of the four main medium supplements; i.e., fish serum, fetal bovine serum, basic fibroblast growth factor, and medaka embryo extract, significantly inhibited growth. The proportion of cells possessing normal chromosome number was 45% and 46.7% of the cell lines, respectively. Taken together, two cell lines that proliferate continuously were established from marine medaka and these cell lines may provide a basic tool for characterizing the unique features of this fish species.

• KSBB Journal
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• v.28 no.4
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• pp.244-248
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• 2013

In order to investigate functional characterization of callus extracts of apple 'Hirosaki' for cosmetic materials, biological activities of its extracts including wrinkle improvement, hair growth, and anti-inflammatory effect were investigated. The callus extract showed similar activity with TGF-${\beta}$ used as positive control at 50 ${\mu}g/mL$ in the test of collagen synthesis, and increased 40% of proliferation of hair follicle dermal papilla cells. Especially, in case of anti-inflammatory effect, callus extract inhibited about 50% of COX-2 expression which was known as response for intermediating inflammation, and about 70% of eotaxin-1 production which was increased by atopy dermatitis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.4
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• pp.173-178
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• 2019

In this study, we demonstrated a characterization of ${\alpha}-Ga_2O_3$ grown on a cone-shape patterned sapphire substrate by using the halide vapor phase epitaxy. An ${\alpha}-Ga_2O_3$ was grown on different size of PSS and c-plane sapphire substrate for comparison to confirm the effect of PSS. In addition, growth time of ${\alpha}-Ga_2O_3$ was gradually increased to confirm growth mechanism of ${\alpha}-Ga_2O_3$ grown on the PSS. A growth temperature was changed to $470-550^{\circ}C$. It can be analyzed growth conditions and mechanisms on the cone-shape PSS, resulting in a significant decrease in the FWHM value of an asymmetric plane (10-14) of ${\alpha}-Ga_2O_3$, due to lateral growth that occurs during the growth process.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.10
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• pp.1508-1514
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• 2016

A series of antagonists specifically targeting growth hormone receptors (GHR) in different species, such as humans, rats, bovines, and mice, have been designed; however, there are currently no antagonists that target the porcine growth hormone (GH). Therefore, in this study, we developed and characterized a porcine GHR (pGHR) antibody antagonist (denoted by AN98) via the hybridoma technique. The results from enzyme-linked immunosorbent assay, fluorescence activated cell sorter, indirect immunoinfluscent assay, and competitive receptor binding analysis showed that AN98 could specifically recognize pGHR, and further experiments indicated that AN98 could effectively inhibit pGH-induced signalling in CHO-pGHR cells and porcine hepatocytes. In addition, AN98 also inhibited GH-induced insulin-like growth factor-1 (IGF-1) secretion in porcine hepatocytes. In summary, these findings indicated that AN98, as a pGHR-specific antagonist, has potential applications in pGH-pGHR-related research on domestic pigs.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.253-269
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• 1999

The development of telecommunication and information technology requires to develop new piezoelectric materials with small size, low impedance, wide pass band width and high thermal stability of frequency. Langasite (La3Ga5SiO14) single crystal has been researched substitute of quartz and LiNbO3 for the applications of SAW filter, BAW filter and resonator. Its single crystal growth has been carried out by Czochralski Method. So, in order to get single crystal with higher quality, in this study, lnagasite (La3Ga5SiO14) single crystal was grown by using Floating Zone (FZ) method and characterized. For the growth of langasite single crystals, the langasite powder was synthesized at 135$0^{\circ}C$ for 5hrs and the feed rod was sintered at 135$0^{\circ}C$ for 5hrs. The growing rate was 1.5mm/h and the rotation speed was 15 rpm for an upper rotation and 13 rpm for a lower rotation. In order to prevent the evaporation of gallium oxide, Ar and O2 gas mixture was flowed. The growth direction was analyzed by Laue back-scattered analysis. The composition of grown crystal was analyzed suing XRD and WDS. The electrical properties of grown crystal at various frequencies and temperature were discussed.