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Effect of palmitoleic acid on the differentiation of bovine skeletal muscle satellite cells

  • Zhang, Junfang;Li, Qiang;Nogoy, Kim Margarette Corpuz;Sun, Jianfu;Sun, Bin;Wang, Ying;Tang, Lin;Yu, Jia;Jin, Xin;Li, Xiangzi;Choi, Seong-Ho
    • Journal of Animal Science and Technology
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    • v.63 no.4
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    • pp.919-933
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    • 2021
  • We hypothesized that the unsaturated fatty acid palmitoleic acid (POA) could promote the expression of adipogenic/lipogenic genes in bovine skeletal muscle satellite cells (BSCs). The BSCs were cultured in a growth medium containing 10% fetal bovine serum. When the cells reached 80%-90% confluence, we used the differentiation medium with 5% horse serum for differentiation for 96 h. The differentiation medium contained 50 µM, 100 µM and 200 µM POA. Control BSC were cultured only in differentiation media. Compared with the control BSC, the POA BSC significantly up-regulated the expression of paired box 3 (Pax3) and paired box 7 (Pax7) and down-regulated myogenin gene expression (p < 0.01), which indicates a depression in muscle fiber development. However, all POA treatments up-regulated the expression of the adipocyte transcription factors peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein alpha and beta (C/EBP α and C/EBP β), and other genes (p < 0.01) and increased the expression of PAT-family proteins and the concentration of adiponectin in the media. These results indicate that POA can convert part of BSCs into adipocytes.

Cascode Low Noise Amplifiers with Coplanar Waveguide Structure for Wireless LAN Application

  • Kim, Jong-Ho;Kim, Ki-Byoung;Lee, Jong-Chul;Kim, Jong-Heon;Lee, Byungje;Kim, Nam-Young
    • Journal of electromagnetic engineering and science
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    • v.3 no.1
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    • pp.12-16
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    • 2003
  • In this paper, low noise amplifiers with coplanar waveguide structure are presented for Wireless LAN data communication application. For comparison of microwave performance, LNAs of cascode type and balanced type using cascode cell with the same substrate and same bias conditions are designed and implemented. A cascode type of LNA shows the gain of 12.45 ㏈, input return loss of 11.63 ㏈, and noise figure of 1.52㏈. A balanced type of LNA using cascode cell shows the gain of 6.58 ㏈, input return loss of 16.6 ㏈, and noise figure of 1.18 ㏈.

Genetic Modification of Coffee Plants

  • Shinjiro Ogita;Hirotaka Uefuji;Park, Yong-Eui;Tomoko Hatanaka;Mikihiro Ogawa;Yube Yamaguchi;Nozomu Koizumi;Hiroshi Sano
    • Journal of Plant Biotechnology
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    • v.4 no.3
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    • pp.91-94
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    • 2002
  • An efficient molecular breeding technique for coffee plants was developed. In order to produce transgenic coffee plants, we established a model transformation procedure via Agrobacterium method. We isolated a gene encoding a protein possessing 7-methylxanthine methyltransferase (theobromine synthase) activity, and it was designated as Coffea arabica 7-methylxanthine methyl transferase; CaMXMT. Using this clone, we produced transgenic coffee plants, in which the expression of CaMXMT is suppressed by double-stranded RNA interference (RNAi) andlor anti-sense methods. The expression pattern of CaMXMT was analyzed by reverse transcription-PCR method and we found that, in the transformed cell lines, the level of transcripts were obviously suppressed by RNAi. The endogenous level of caffeine in the transformed cells was dramatically reduced in comparison with non-transformed cells.

Flocculation Effect of Alkaline Electrolyzed Water (AEW) on Harvesting of Marine Microalga Tetraselmis sp.

  • Lee, Su-Jin;Choi, Woo-Seok;Park, Gun-Hoo;Kim, Tae-Ho;Oh, Chulhong;Heo, Soo-Jin;Kang, Do-Hyung
    • Journal of Microbiology and Biotechnology
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    • v.28 no.3
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    • pp.432-438
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    • 2018
  • Microalgae hold promise as a renewable energy source for the production of biofuel, as they can convert light energy into chemical energy through photosynthesis. However, cost-efficient harvest of microalgae remains a major challenge to commercial-scale algal biofuel production. We first investigated the potential of electrolytic water as a flocculant for harvesting Tetraselmis sp. Alkaline electrolyzed water (AEW) is produced at the cathode through water electrolysis. It contains mineral ions such as $Na^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ that can act as flocculants. The flocculation activity with AEW was evaluated via culture density, AEW concentration, medium pH, settling time, and ionic strength analyses. The flocculation efficiency was 88.7% at 20% AEW (pH 8, 10 min) with a biomass concentration of 2 g/l. The initial biomass concentration and medium pH had significant influences on the flocculation activity of AEW. A viability test of flocculated microalgal cells was conducted using Evans blue stain, and the cells appeared intact. Furthermore, the growth rate of Tetraselmis sp. in recycled flocculation medium was similar to the growth rate in fresh F/2 medium. Our results suggested that AEW flocculation could be a very useful and affordable methodology for fresh biomass harvesting with environmentally friendly easy operation in part of the algal biofuel production process.

New Harmonic Suppressed Microstirp Ring Bandpass Filters

  • Park, Hyun-Joo;Kim, Jae-Hyuk;Park, Ji-Yong;Lee, Jong-Chu;Kim, Jong-Heon;Lee, Byung-Je;Kim, Nam-Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.5
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    • pp.697-706
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    • 2000
  • In this paper, new bandpass filters that are composed of microstrip ring resonators with the center frequency of 5.775 GHz and the bandwidth of 100 MHz are presented. For the suppression of the unnecessary harmonics, lowpass filters are inserted into the feedlines and ring resonator itself, respectively These bandpass filters show good microwave characteristics with the harmonic suppression ratio of about 39 dB and 35 dB, respectively. Also, the varactor-tuned microstip ring bandpass filter with harmonic suppression is suggested and the tuning bandwidth of more than 450 MHz is obtained.

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