• Communications for Statistical Applications and Methods
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• v.31 no.3
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• pp.263-277
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• 2024

This paper proposes new parameterizations of the tilted beta binomial distribution, obtained from the combination of the binomial distribution and the tilted beta distribution, where the beta component of the mixture is parameterized as a function of their mean and variance. These new parameterized distributions include as particular cases the beta rectangular binomial and the beta binomial distributions. After that, we propose new linear regression models to deal with overdispersed binomial datasets. These new models are defined from the proposed new parameterization of the tilted beta binomial distribution, and assume regression structures for the mean and variance parameters. These new linear regression models are fitted by applying Bayesian methods and using the OpenBUGS software. The proposed regression models are fitted to a school absenteeism dataset and to the seeds germination rate according to the type seed and root.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.647-654
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• 1992

In order to study the physiological properties of the intestinal bacteria, we isolated the intestinal bacteria of Koreans and tested the enzymatic patterns. Isolated Bifidobacterium sp. Int-57 had the higher activity of $\alpha$-glucosidase, $\beta$-glucosidase, $\alpha$-galactosidase, $\beta$-galactosidase. $\beta$-xylosidase and $\alpha$-arabinofuranosidase than other intestinal microorganisms. The effect of the carbon sources on the production of each enzymes of Bijidobacterium sp. Int-57 was investigated. The most suitable carbon source for the production of $\beta$-glucosidase was maltose, for a-glucosidase cellobiose, for $\alpha$-galactosidase raffinose, for $\beta$-galactosidase lactose, and for $\beta$-xylosidase and $\alpha$-arabinofuranosidase xylose, respectively. In addition, we investigated the optimal conditions and pH stability of each crude enzymes. The optimal condition of a-glucosidase was pH 6.0 and $40^{\circ}C$. that of Jj-glucosidase pH 7.0 and 50oe, that of $\beta$-galactosidase pH 7.0 and $50^{\circ}C$, that of $\beta$-xylosidase pH 6.0 and $40^{\circ}C$ , and that of $\alpha$-arabinofuranosidase pH 5.0 and $50^{\circ}C$. respectively. a-Glucosidase was stable at pH 4.0-9.0. Jj-glucosidase at pH 4.0-7.0. $\beta$-galactosidase at pH 4.0-9.0, $\beta$-xylosidase at pH 4.0-6.0, and /3-arabinofuranosidase at pH 7.0-9.0, respectively.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.299-304
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• 2003

A strain YB-9 was isolated from soil as a producer of the extracellular ${\beta}-D-galactosidase$, which catalyzes the hydrolysis of lactose. The strain YB-9 was identified as Streptomyces sp. on the basis of its cultural, morphological and physiological properties. After treating culture supematant of the isolate with ammonium sulfate $(15{\sim}70%)$, the precipitated protein was used as a crude ${\beta}-galactosidase$ for analyzing its reaction properties with $para-nitrophenyl-{\beta}-D-galactoside$ $(pNP-{\beta}Gal)$ and lactose as substrates. The {\beta}-galactosidase showed its maximal activity at pH $6.0{\sim}6.5$ and $60^{\circ}C$. The hydrolyzing activity of ${\beta}-galactosidase$ for both $pNP-{\beta}Gal$ and lactose was decreased by galactose. Its hydrolyzing activity for lactose was slightly decreased by glucose, but the activity for $pNP-{\beta}Gal$ was increased to 1.3-folds by glucose. Especially, its hydrolyzing activity was not affected for lactose and was increased to 1.6-folds for $pNP-{\beta}Gal$ by xylose.

• Biomedical Science Letters
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• v.11 no.2
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• pp.175-183
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• 2005

The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.136-140
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• 2000

Two steroidal saponins were isolated from MeOH extract of the rhizomes of Asparagus oligoclonos. Using the spectroscopic techniques of $^1H,\;^{13}C$ NMR and 2D NMR, they were identified as $3-O-[{\beta}-D-glucopyranosyl-(1{\rightarrow}2)-{\beta}-D-glucopyranosyl]-(25S)-spirostan-3{\beta}-ol$ and $3-O-{{\beta}-D-glucopyranosyl-(1{\rightarrow}2)-[{\beta}-D-xylopyranosyl-(1{\rightarrow}4)]-{\beta}-D-glucopyranosyl}-(25S)-spirostan-3{\beta}-ol$, respectively. They were first isolated from A. oligoclonos. The in vitro antibacterial activities as well as antibacterial spectrums against 20 bacteria strains were investigated with MIC test. Both saponins inhibited the growth of 10 bacteria strains at the concentration of$100\;{\mu}g/ml$.

• Development and Reproduction
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• v.3 no.1
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• pp.59-67
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• 1999

To investigate the role of interleukin-l$\beta$ (IL-1$\beta$) in the embryonic development, in vivo and in vitro expression patterns of IL-1$\beta$ gene in the preimplantation mouse embryos were examined by RT-PCR, and the effects of explanted mouse ovi-duct and uterine epithelial cells on the expression of IL-1$\beta$ gene in the pleimplantation mouse embryos were examined by co-culture. IL-1$\beta$ mRNA was detected in the embryos from 4-cell stage to blastocyst stage in vivo and from morula stage to hatching blastocyst stage in vitro. This transcript was not detected from the GV stage to late 2-cell stage in vivo, and not at the 4-cell and 8-cell stages in vitro. For the co-culture of late 2-cell embryos with the explanted mouse oviduct and uterine epithelial cells, oviducts and uterine epithelial cells were isolated at 48 hour alter the hCG injection. The explanted oviduct and uterine epithelial cells in co-culture groups facilitated the IL-1$\beta$ gene expression of the mouse embryos in comparison with the control. Taken together these results suggest that the presence of IL-1$\beta$ plays an important role in preimplantation embryonic development. In addition, the up-regulation of IL-1$\beta$ gene expression by the explanted oviduct and uterine epithelial cells demonstrates that embryonic expression of IL-l$\beta$ gene may be regulated by the interaction with oviductal and uterine factor (s).

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.180-185
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• 2007

This study demonstrates that pork cholesterol levels are reduced in fattening stage swine fed $\beta-cyclodextrin({\beta}-cyclodextrin)$. The study subjects were 120 swine fed their respective chow diets containing 0, 5, 7, or 10% $\beta$-cyclodextrin for 35 consecutive days. Plasma total lipids, triglyceride and total cholesterol of the $\beta$-cyclodextrin treated group were significantly lower than those of the control group (p<0.05). The levels of plasma lipid were significantly decreased by 63.22 mg, 73.98 mg, and 82.12 mg in the fattening swine group fed $\beta$-cyclodextrin at 5%, 7%, and 10%, respectively, compared to those in the control group (p<0.05). When 5, 7, and 10% $\beta$-cyclodextrin was administered to fattening swine, the triacylglyceride levels were decreased by 56.24 mg, 55.48 mg, and 60.02 mg, and total cholesterol concentration was reduced by 25.05 mg, 27.17 mg, and 30.19 mg, respectively, compared to those in the control group (p<0.05). Excretion of total steroid significantly (p<0.05) increased with the increasing amount of $\beta$-cyclodextrin supplementation. The cholesterol levels of swine back fat, belly, loin, and ham were significantly decreased with increasing $\beta$-cyclodextrin supplementation (p<0.05). The pork cholesterol was significantly (p<0.05) reduced by 15.31% in the $\beta$-cyclodextrin treated group, compared to that of the control group. These results suggest that feeding $\beta$-cyclodextrin to fattening swine may produce novel functional pork with low cholesterol levels.

• Journal of Life Science
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• v.29 no.2
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• pp.256-264
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• 2019

Lymphotoxin ${\beta}$ receptor ($LT{\beta}R$), a member of the tumor necrosis factor receptor family, plays an important role in lymphoid tissue's architecture and organogenesis. In contrast, MLCK and ROCK play critical roles in the regulation of stress fiber (SF) formation in cells. To determine whether $LT{\beta}R$ stimulation in fibroblastic reticular cells (FRCs) is involved in these signaling pathways, myosin light chain kinase inhibitor-7 (ML-7) was used to inhibit them. ML7-treated FRCs completely blocked SFs and showed retraction and shrinkage processes comparable to those observed in agonistic anti-$LT{\beta}R$ antibody-treated cells. The inhibition of ROCK activity with Y27632-induced changes in actin cytoskeleton organization and cell morphology in FRCs. Actin bundles rearranged into SFs, and phospho-myosin light chain (p-MLC) co-localized in FRCs. We checked the level of Rho-guanosine diphosphate (RhoGDP)/guanosine triphosphate (GTP) exchange activity using FRC lysate. When $LT{\beta}R$ was stimulated with agonistic anti-$LT{\beta}R$ antibodies, Rho-GDP/GTP exchange activity was markedly reduced. Regarding $LT{\beta}R$ signaling with a focus on MLCK inhibition, we showed that the phosphorylation of MLCs was reduced by $LT{\beta}R$ stimulation in FRCs. Cytoskeleton components, such as tubulin, b-actin, and phospho-ezrin proteins acting as membrane-cytoskeleton linkers, were produced in de-phosphorylation, and they reduced expression in agonistic anti-$LT{\beta}R$ antibody-treated FRCs. Collectively, the results suggested that MLCK and ROCK were simultaneously responsible for SF regulation triggered by $LT{\beta}R$ signaling in FRCs.

• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.255-259
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• 1996

$\beta$-Glucosidase was known to be involved in the mutagenic activation of $\beta$-glucosides. The level of $\beta$-glucosidase in the feces of adults was 2.7 times higher than that of infants. There was no difference in the percentage of $\beta$-glucosidase positive strains among Bifidobacterium isolates between adults and infants, corresponding to 90 and 92$%$, respectively. However, the strains from adults showed 1.9 times higher enzyme activity than those from infants when grown in Brain Heart Infusion medium. $\beta$-Glucosidase negative strains could not ferment $\beta$-glucosidase substrates, such as cellobiose, salicin, naringin, esculin and arbutin. Presence of $\beta$-glucosidase in Bifidobacterium did not alter the degree of growth in reconstituted skim milk. The $\beta$-glucosidase level was much lower in milk and vegetable medium, although cells grew above $10^8$cfu/ml, than in BHI medium. This study suggests that metabolic activation of the $\beta$-glucosides by Bifidobacterium $\beta$-glucosidase varies significantly depending on types of growth medium.

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.364-368
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• 1987

The addition reactions of thioglycolic acid, benzenethiol and benzylmercaptan to ${\beta}-acetyl-{\beta}-benzoylstyrene$ were investigated. ${\beta}-Acetyl-{\beta}-benzoylstyrene$ derivatives easily underwent addition reactions with thioglycolic acid, benzenethiol, and benzylmercaptan to form five(2-acetyl-2-benzoyl-1-phenylethyl) thioglycolic acid derivatives (IIa-IIe), five (2-acetyl-2-benzoyl-1-phenylethyl)benzenethiol (IIIa-IIIe) derivatives and five (2-acetyl-2-benzoyl-1-phenylethyl)benzylmercaptan derivatives (IVa-IVe), respectively.