• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.338-343
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• 1990

MB4-03, an $\alpha$-amylase inhibitor was isolated from the culture broth of Streptomyces sp. DMCJ-49 and purified through ion-exchange chromatography, adsorption, and gel filtration. The results of various instrumental analyses showed that the inhibitor was one of oligosaccharides that had glucoses as its major component and that its molecular weight was about 2000. And one methyl group which seemed to be related with the inhibitory activity of this compound was identified. From the CMR spectrum, it was elucidated that this compound was composed of $\alpha$ -D-glucopyranoses which were linked together by $\alpha$ (I -, 4) bond configuration. As the inhibitory effect of this compound was reduced after incubation with $\beta$-amylase, the maltose units was seemed to exist at non-reducing terminal side of it.

• Archives of Pharmacal Research
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• v.12 no.1
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• pp.42-47
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• 1989

From the roots of Puisatiila koreana, three monodesmosides(pulsatilla saponins A, B and D) and two bisdesmosides(pulsatilla saponins F and H) were isolated. The structure of these saponins have been determined as hederagenin 3-O-${\beta}$-L-rhamnopyranosyl($1{\to}2$)- ${\alpha}$-L-arabinopyranoside(A), hederagenin 3-O-${\beta}$-D-glucopyrano syl($1{\to}4$) - ${\alpha}$-L-arabinopyranoside(B), hederagenin 3-O- ${\alpha}$-L-rhamnopyranosyl ($1{\to}2$)-[${\beta}$-D-glucopyranosyl($1{\to}4$]-${\alpha}$-L-arabinopyranoside(D), 3-O-${\alpha}$-L-rhamnopyranosyl($1{\to}2$)-{${\alpha}$-L-arabinopyranosyl hederagenin 28-O-${\alpha}$-L-rhamnopyrano syl($1{\to}4$)-${\beta}$-D-glucopyrano syl($1{\to}6$)-${\beta}$-D-glucopyranosyI ester (F) and 3-O-${\alpha}$-L-rhamnopyranosyl($1{\to}2$)-[${\beta}$-D-glucopyranosyl($1{\to}4$)]- ${\alpha}$-L-arabinopyranosyl hederagenin 28-O-${\alpha}$-L-lharnnopyranosyl($1{\to}4$)-${\beta}$-D-glucopyranosyl($1{\to}6$)-${\beta}$-D-glucop yranosyl ester(H) on the basis of chemical and spectral studies. Pulsatilla saponin B is the first report of its presence in plants but saponins A, D, F, and H have recently been isolated from the same genus p. cernua.

• Biomedical Science Letters
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• v.25 no.1
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• pp.23-31
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• 2019

The protein kinase $CK2{\alpha}$ (formerly Casein Kinase II) is implicated in tumorigenesis and transformation. However, the mechanisms of $CK2{\alpha}$ activation in breast cancer have yet to be elucidated. This study investigated the mechanisms of $CK2{\alpha}$ activation in estrogen signaling. Estrogen increased reactive oxygen species (ROS) production, $CK2{\alpha}$ activity, and protein expression in estrogen receptor positive ($ER^+$) MCF-7 human breast cancer cells, which were inhibited by the antioxidant N-acetyl-L-cysteine. $H_2O_2$ enhanced $CK2{\alpha}$ activity and protein expression. Human epidermal growth factor (EGF) increased ROS production, $CK2{\alpha}$ activity and protein expression in EGF receptor 2 (HER2)-overexpressing MCF-7 (MCF-7 HER2) cells, but not in MCF-7 cells. Estrogen induced the phosphorylation of p38 mitogen-activated protein kinase (MAPK). The p38 inhibitor, SB202190, blocked estrogen-induced increases in ROS production, $CK2{\alpha}$ activity and $CK2{\alpha}$ protein expression. The data suggest that ROS/p38 MAPK is the key inducer of $CK2{\alpha}$ activation in response to estrogen or EGF.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2204-2212
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• 2022

Recently, the demand for alpha imaging detectors for quantifying the distributions of alpha particles has increased in various fields. This study aims to reconstruct a high-resolution image from an alpha imaging detector by applying a super-spatial resolution method combined with the maximum-likelihood expectation maximization (MLEM) algorithm. To perform the super-spatial resolution method, several images are acquired while slightly moving the detector to predefined positions. Then, a forward model for imaging is established by the system matrix containing the mechanical shifts, subsampling, and measured point-spread function of the imaging system. Using the measured images and system matrix, the MLEM algorithm is implemented, which converges towards a high-resolution image. We evaluated the performance of the proposed method through the Monte Carlo simulations and phantom experiments. The results showed that the super-spatial resolution method was successfully applied to the alpha imaging detector. The spatial resolution of the resultant image was improved by approximately 12% using four images. Overall, the study's outcomes demonstrate the feasibility of the super-spatial resolution method for the alpha imaging detector. Possible applications of the proposed method include high-resolution imaging for alpha particles of in vitro sliced tissue and pre-clinical biologic assessments for targeted alpha therapy.

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.27-32
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• 2007

This study was conducted to examine the effects of prostaglandin $F_2{\alpha}(PGF_2{\alpha})$ and prostaglandin $E_2 (PGE_2)$ on the expansion and hatching of bovine embryos. During the in vitro culture, embryos were cultured with the following groups: (1) 0, 1, 10 and 100ng/ml $PGF_2{\alpha}$ (2) 0, 1, 10 and 100 ng/ml $PGF_2{\alpha}$, (3) low concentration of $PGF_2{\alpha}$ ; low concentration of $PGF_2{\alpha}$, (1ng/ml : 1ng/ml), (4) low concentration of $PGF_2{\alpha}$ : high concentration of $PGF_2{\alpha}$ (1ng/ml : 10ng/ml) (5) high concentration of $PGF_2{\alpha}$ : low concentration of $PGE_2$ (10ng/ml 1ng/ml) (6) high concentration of $PGF_2{\alpha}$ : high concentration of $PGE_2$(10 ng/ml : 10ng/ml). In the results of this study, treatment of $PGF_2{\alpha}$ or $PGE_2$ did not affect in vitro development to blastocysts. However, the hatching rates of embryos cultured with 10ng/ml $PGE_2$(10.3%) and 1ng/ml $PGF_2{\alpha}$ 10ng/ml $PGE_2$(22.2%) were significantly (P<0.05) higher than in control (4.3% and 12.7%) and other treatment groups. All groups treated with high concentrations of $PGF_2{\alpha}$ showed decreased hatching rates. Thus, this results suggested that $PGF_2{\alpha}\;and\;PGE_2$ were concerned with the hatching in bovine embryos, and their effects on hatching were different by the concentrations.

• Journal of Veterinary Clinics
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• v.29 no.5
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• pp.361-367
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• 2012

Diabetes-related complications in human and veterinary medicine have been shown to be associated with hyperglycemia-induced inflammation. It has been recently suggested that the onset of insulin resistance may be caused by over-production of inflammatory cytokines such as tumor necrosis factor (TNF)-${\alpha}$ from immune cells. Conjugated linoleic acid (CLA) regulates inflammatory response through modulation of TNF-${\alpha}$ expression. The objective of this study was to examine the effect of CLA on nuclear factor kappaB (NF-${\kappa}B$) p65 binding activity, inhibitory kappaB ($I{\kappa}B$)-${\alpha}$ expression, and TNF-${\alpha}$ production from high glucose-treated RAW 264.7 cells. CLA was added to RAW cells that had been previously cultured with low or high concentration of glucose. The levels of TNF-${\alpha}$ protein in the culture supernatant of RAW cells exposed to high concentrations of glucose were higher than those of cells exposed to low concentrations of glucose. The treatment with the high concentration of glucose in RAW cells increased levels of NF-${\kappa}B$ p65 binding activity and the decreased $I{\kappa}B-{\alpha}$ expression when compared with those of low glucose. The treatments in combination with CLA and glucose (low and high) glucose in RAW cells increased TNF-${\alpha}$ production when compared with that glucose alone. These treatments with CLA increased TNF-${\alpha}$ production in high glucose-treated RAW cells than those with low glucose. These treatments of CLA also showed higher NF-${\kappa}B$ p65 binding activity and lower $I{\kappa}B-{\alpha}$ expression in high glucose than those in low glucose condition. This suggests that CLA can increase NF-${\kappa}B$ p65 binding activity and TNF-${\alpha}$ production from high glucose-treated RAW 264.7 cells and is likely to promote hyperglycemia-induced inflammation.

• Korean Journal of Medicinal Crop Science
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• v.15 no.1
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• pp.30-37
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• 2007

It is well-known that Korean mistletoe (Viscum album) extract has an immune activity and anticancer effect. In this study, Korean mistletoe extract, M11C (non-lectin components), was used to examine whether this extract might activate human peripheral monocyte to produce tumor necrosis $factor-\alpha$ $(TNF-\alpha)$. To examine the effect of M11C on the production of $TNF-\alpha$ from monocyte, the monocyte were stimulated by the M11C, and then collected the supernatant (M11C stimulated monocyte-conditioned media; MCM). MCM was treated to the $TNF-\alpha$ sensitive L929 cells, and then L929 cytotoxicity was measured by means of MTT. MCM had cytotoxic effect on L929. And the cytotoxic effect of MCM on L929 was almost abolished by $anti-TNF-\alpha$ antibody. These data indicated that MCM contained $TNF-\alpha$, suggesting the $TNF-\alpha$ generation from M11C-stimulated monocyte. This suggestion was confirmed from the data that $TNF-\alpha$ was highly detected in MCM by immunoblotting technique. M11C effect on $TNF-\alpha$ production from monocyte was in the dose and stimulating time dependent manners. Also the effect of M11C on the expression of $TNF-\alpha$ mRNA from monocyte was shown in the dose and stimulating time dependent manners. As a result, Korean mistletoe extract, M11C, could be used for an immunostimulator.

• Honam Mathematical Journal
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• v.35 no.3
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• pp.343-350
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• 2013

In this paper we prove that if Toeplitz operators $T^{\alpha}_u$ with symbols in RW satisfy ${\parallel}uk^{\alpha}_z{\parallel}_{s,{\alpha}{\rightarrow}0$ as $z{\rightarrow}{\partial}\mathbb{D}$ then $T^{\alpha}_u$ is compact and also prove that if $T^{\alpha}_u$ is compact then the Berezin transform of $T^{\alpha}_u$ equals to zero on ${\partial}\mathbb{D}$.

• Journal of applied mathematics & informatics
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• v.2 no.2
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• pp.83-95
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• 1995

Given a closed subset of the family $S^{*}(\alpha)$ of functions starlike of order $\alpha$, a continuous Frechet differentiable functional J, is constructed with this collection as the solution set to the extremal problem ReJ(f) over $S^{*}(\alpha)$. The support points of $S^{*}(\alpha)$ is completely characterized and shown to coincide with the extreme points of its convex hulls. Given any finite collection of support points of $S^{*}(\alpha)$ a continuous linear functional J, is constructed with this collection as the solution set to the extremal problem ReJ(f) over $S^{*}(\alpha)$.

• Communications of the Korean Mathematical Society
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• v.27 no.3
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• pp.603-611
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• 2012

We introduce the concept of fuzzy $r$-minimal ${\alpha}$-open set on a fuzzy minimal space and some basic properties. We also introduce the concepts of fuzzy $r$-M ${\alpha}$-continuous and fuzzy $r$-M($M^*$) ${\alpha}$-open mappings, and investigate characterization for such mappings.