• Applied Biological Chemistry
• /
• 제7권
• /
• pp.1-13
• /
• 1966

(1) 콩과 식물인 guar (Cyamopsis tetragonolobus)의 발아종자(發芽種子)에서 세 가지의 다른 다당류가수분해효소(多糖類加水分解酵素)인 ${\beta}-1$, 4-mannanase A,B,C 를 추출(抽出), 유안염석(硫安鹽析), 이온교환(交換)크로마토그래휘 및 젤여과법(濾過法)에 의하여 분리(分離), 정제(精製)하였다. (2) 이들 효소(酵素)는 작용최적(作用最適) pH, 급속이온의 영향, 분자량(分子量), ior nut mannan A에 대한 Michaelis 항수(恒數), 가수분해(加水分解)의 한도(限度) 및 생성물등(生成物等) 여러 가지 점(點)에서 다르다. (3) ${\beta}-1$, 4-Mannanase A 와 C 는 기질(基質)인 ${\beta}-1$, 4-mannanase 에 random으로 작용(作用)하여 과당류(寡糖類)를 생성(生成)하는 endo형(型) 효소(酵素)임이 밝혀졌다. 한편 ${\beta}-1$, 4-mannanase B 는 같은 기질(基質)의 비환원말단기(非還元末端基)로 부터 수차로 작용(作用)하여 단당류(單糖類)를 생성(生成)하는 exo형(型) 효소(酵素)로 추리(推理)된다. (4) Guar 종자중(種子中)의 galactomannan 인 guaran에 이들 정제효소(精製酵素)를 작용(作用)시킨 결과(結果)로부터 기질(基質)의 구조(構造) 및 guar 종자(種子)의 발아중(發芽中)에 가지는 역할(役割)과 관련시켜 논의(論議)하였다.

• International Journal of Oral Biology
• /
• 제39권2호
• /
• pp.107-114
• /
• 2014

Taste is an important sense in survival and growth of animals. The growth and maintenance of taste buds, the receptor organs of taste sense, are under the regulation of various neurotrophic factors. But the distribution aspect of neurotrophic factors and their receptors in distinct taste cell types are not clearly known. The present research was designed to characterize mRNA expression pattern of neurotrophic factors and their receptors in distinct type of taste cells. In male 45-60 day-old Sprague-Dawley rats, epithelial tissues with and without circumvallate and folliate papillaes were dissected and homogenized, and mRNA expressions for neurotrophic factors and their receptors were determined by RT-PCR. The mRNA expressions of brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3), receptor tyrosine kinase B (TrkB), exclusion of nerve growth factor (NGF), neurotrophin-4/5 (NT4/5), receptor tyrosine kinase A (TrkA), receptor tyrosine kinase C (TrkC), and p75NGFR were observed in some population of taste cell. In support of this result and to characterize which types of taste cells express NT3, BDNF, or TrkB, we examined mRNA expressions of NT3, BDNF, or TrkB in the $PLC{\beta}2$ (a marker of Type II cell)-and/or SNAP25 (a marker of Type III cell)-positive taste cells by a single taste cell RT-PCR and found that the ratio of positively stained cell numbers were 17.4, 6.5, 84.1, 70.3, and 1.4 % for $PLC{\beta}2$, SNAP25, NT3, BDNF, and TrkB, respectively. In addition, all of $PLC{\beta}2$-and SNAP25-positive taste cells expressed NT3 mRNA, except for one taste bud cell. The ratios of NT3 mRNA expressions were 100% and 91.7% in the SNAP25-and $PLC{\beta}2$-positive taste cells, respectively. However, two TrkB-positive taste cells co-expressed neither $PLC{\beta}2$ nor SNAP 25. The results suggest that the most of type II or type III cells express BDNF and NT3 mRNA, but the expression is shown to be less in type I taste cells.

• Kyungpook Mathematical Journal
• /
• 제46권1호
• /
• pp.19-29
• /
• 2006

In this paper, we obtain some inequalities similar to Hilbert type. Some new inequalities are also given.

• 대한수학회보
• /
• 제54권4호
• /
• pp.1293-1307
• /
• 2017

General (${\alpha},{\beta}$)-metrics form a rich class of Finsler metrics. They include many important Finsler metrics, such as Randers metrics, square metrics and spherically symmetric metrics. In this paper, we find equations which are necessary and sufficient conditions for such Finsler metric to be locally projectively flat. By solving these equations, we obtain all of locally projectively flat general (${\alpha},{\beta}$)-metrics under certain condition. Finally, we manufacture explicitly new locally projectively flat Finsler metrics.

• 한국재료학회:학술대회논문집
• /
• 한국재료학회 1999년도 추계학술발표강연 및 논문개요집
• /
• pp.95-95
• /
• 1999

• Applied Microscopy
• /
• 제22권2호
• /
• pp.84-96
• /
• 1992

Turtle bladder 상피세포(上皮細胞)의 수송기작(輸送機作)을 in vitro에서 효과적으로 연구하기 위하여 Lucite chamber 한가운데 상피조직을 두고 전압고정법(電壓固定法)을 적용하여 상피 세포층의 막전위(膜電位)를 측정한 후 급속 동결(凍結)하고 투과 및 주사형 전자현미경(電子顯微鏡)으로 탄산 탈수효소를 함유하는 세포의 표면막 특성을 분석(分析)하였다. 방광(膀胱)의 점막층(粘膜層)은 두 타입의 탄산탈수효소를 함유한 세포가 특징적인데 정단부(丁端部)와 기저부(基底部) 세포막에서는 각기 다른 수송의 특성을 나타내고 있다. 즉 ${\alpha}$ 및 ${\beta}$형 탄산탈수효소가 풍부한 세포는 정단세포막(丁端細胞膜)의 proton 펌프를 이용하여 $H^+$ 분필(分泌)에 관여하거나 bicarbonate의 재흡수(再吸收) 기능을 가지는 것으로 믿어진다. 본 연구에서 탄산탈수효소를 함유한 ${\alpha}$형의 세포의 proton 분필수송(分泌輸送)과 세포막 투과성 변화와의 상관관계를 관찰하였는 바, 이들 세포에서 $H^+$을 분비하는 과정에서 정단부의 표면세포막(表面細胞膜) P-face에는 특이한 구조로서 세포막내(細胞膜內) 입자(粒子)들이 다량으로 분포하였다. 이와같은 세포막내(細胞膜內) 입자(粒子)들은 proton 펌프를 함유하는 것으로 생각되며 ${\beta}$형의 세포에서는 기저세포막(基底細胞膜)에서 관찰되고 있다. 이와같은 결과는 방광상피(膀胱上皮) 세포내 탄산탈수효소는 $H^+$과 $HCO_{3}^{-}$의 생성에 관여하지만, 특히 ${\alpha}$형 세포에서 정단세포막의 proton 펌프를 이용한 $H^{+}$ 분필수송(分泌輸送)과 기저세포막을 통한 bicarbonate의 재흡수(再吸收) 기능을 설명해 주는 중요한 사실로서 사료된다.

• Mycobiology
• /
• 제38권2호
• /
• pp.144-148
• /
• 2010

$\beta$-Glucans have been known to exhibit antitumor activities by potentiating host immunity by an unknown mechanism. The C-type lectin dectin-1, a $\beta$-glucan receptor, is found on the macrophage and can recognize various $\beta$-glucans. Previously, we demonstrated the presence of $\beta$-glucan receptor, dectin-1, on the Raw 264.7 cells as well as on murine mucosal organs, such as the thymus, the lung, and the spleen. In order to investigate immunopotentiation of innate immunity by $\beta$-glucan, we stimulated a murine macrophage Raw 264.7 cell line with $\beta$-glucans from Pleurotus ostreatus, Saccharomyces cerevisiae, and Laminaria digitata. Then, we analyzed cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6 by reverse transcription-polymerase chain reaction (RT-PCR). In addition we analyzed gene expression patterns in $\beta$-glucan-treated Raw 264.7 cells by applying total mRNA to cDNA microarray to investigate the expression of 7,000 known genes. When stimulated with $\beta$-glucans, the macrophage cells increased TNF-$\alpha$ expression. When co-stimulation of the cells with $\beta$-glucan and lipopolysaccharide (LPS), a synergy effect was observed by increased TNF-$\alpha$ expression. In IL-6 expression, any of the $\beta$-glucans tested could not induce IL-6 expression by itself. However, when co-stimulation occurred with $\beta$-glucan and LPS, the cells showed strong synergistic effects by increased IL-6 expression. Chip analysis showed that $\beta$-glucan of P. ostreatus increased gene expressions of immunomodulating gene families such as kinases, lectin associated genes and TNF-related genes in the macrophage cell line. Induction of TNF receptor expression by FACS analysis was synergized only when co-stimulated with $\beta$-glucan and LPS, not with $\beta$-glucan alone. From these data, $\beta$-glucan increased expressions of immunomodulating genes and showed synergistic effect with LPS.

• Molecules and Cells
• /
• 제19권2호
• /
• pp.219-222
• /
• 2005

The a-subunit of Escherichia coli tryptophan synthase (${\alpha}TS$), a component of the tryptophan synthase ${\alpha}_2{\beta}_2$ complex, is a monomeric 268-residues protein (Mr = 28,600). ${\alpha}TS$ by itself catalyzes the cleavage of indole-3-glycerol phosphate to glyceraldehyde-3-phosphate and indole, which is converted to tryptophan in tryptophan biosynthesis. Wild-type and P28L/Y173F double mutant ${\alpha}$-subunits were overexpressed in E. coli and crystallized at 298 K by the hanging-drop vapor-diffusion method. X-ray diffraction data were collected to $2.5{\AA}$ resolution from the wild-type crystals and to $1.8{\AA}$ from the crystals of the double mutant, since the latter produced better quality diffraction data. The wild-type crystals belonged to the monoclinic space group C2 ($a=155.64{\AA}$, $b=44.54{\AA}$, $c=71.53{\AA}$ and ${\beta}=96.39^{\circ}$) and the P28L/Y173F crystals to the monoclinic space group $P2_1$ ($a=71.09{\AA}$, b=52.70, $c=71.52{\AA}$ and ${\beta}=91.49^{\circ}$). The asymmetric unit of both structures contained two molecules of ${\alpha}TS$. Crystal volume per protein mass ($V_m$) and solvent content were $2.15{\AA}^3\;Da^{-1}$ and 42.95% for the wild-type and $2.34{\AA}^3\;Da^{-1}$ and 47.52% for the double mutant.

• Archives of Pharmacal Research
• /
• 제14권2호
• /
• pp.137-142
• /
• 1991

The structure of a $\beta$-allyl type phenylpropanoid was determined by single crystal X-ray diffraction analysis. The compound was recrystallized from a mixture of n-hexane and benzene in monoclinic crystal system with a = 24.782 (2), b = 10.537 (1), c = 7.871 (1) ${\AA}, \beta=95.74$ (1)$^\circ, $D_x$=1.216, $D_m$=1.22g/$cm^3$, space group $P2_1/a$, and Z=4. The structure was solved by direct method and refined by least-squares procedure to the final R value of 0.054 for 2824 observed reflections {$F{\geq}3\sigma(F)$}. The molecular geometry shows a most stable trans-form with respect to the bulky phenyls, and this conformation is settled by an intramolecular hydrogen bond. In the crystal, the molecules are arranged along with the screw axis, and stabilized by the $O{\cdot}H{\cdots}O$ type intermolecular hydrogen bonds. The other intermolecular contacts appear to be the normal van der Waals' interactions. The compound is a dimeric phenylpropanoid, and belongs to the neolignan analogues.

• 센서학회지
• /
• 제23권3호
• /
• pp.170-172
• /
• 2014

$CO_2$ sensor was used only one solid electrolyte in many cases. To improve the sensing characteristics of $CO_2$ sensors, solid electrolyte $CO_2$ sensor has been developed by bi-electrolyte type sensor using Na-Beta-alumina and YSZ. However, in many further studies, bi-electrolyte type sensor was made by pellet pressed by press machine and additional treatment for formation of interface. In the aspect of mass production, using thick film and additional treatment is not suitable. In this study, $CO_2$ sensor was fabricated by bi-electrolyte structure which was made by an NBA paste layer deposited on YSZ pellet and fired at $1650^{\circ}C$ for 2 hour. The formation of stable interface between YSZ and NBA were confirmed by SEM image. When the type IV electrochemical cell arrangement represented by $CO_2,O_2,Pt{\mid}Li_2CO_3-CaCO_3{\parallel}NBA{\parallel}YSZ{\mid}O_2,Pt$ is used to measure the $CO_2$ concentration in air. This sensor EMF should depend only on the concentration of $CO_2$ by logarithmic. Also, sensor shows $P_{CO_2}$ and EMF relationship like nerstian reaction at a temperature of $450^{\circ}C$.