• Journal of the Korea Society of Computer and Information
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• v.20 no.8
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• pp.29-33
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• 2015

This paper proposes a discrete logarithm algorithm that remarkably reduces the execution time of Pollard's Rho algorithm. Pollard's Rho algorithm computes congruence or collision of ${\alpha}^a{\beta}^b{\equiv}{\alpha}^A{\beta}^B$ (modp) from the initial value a = b = 0, only to derive ${\gamma}$ from $(a+b{\gamma})=(A+B{\gamma})$, ${\gamma}(B-b)=(a-A)$. The basic Pollard's Rho algorithm computes $x_i=(x_{i-1})^2,{\alpha}x_{i-1},{\beta}x_{i-1}$ given ${\alpha}^a{\beta}^b{\equiv}x$(modp), and the general algorithm computes $x_i=(x_{i-1})^2$, $Mx_{i-1}$, $Nx_{i-1}$ for randomly selected $M={\alpha}^m$, $N={\beta}^n$. This paper proposes 4-model Pollard Rho algorithm that seeks ${\beta}_{\gamma}={\alpha}^{\gamma},{\beta}_{\gamma}={\alpha}^{(p-1)/2+{\gamma}}$, and ${\beta}_{{\gamma}^{-1}}={\alpha}^{(p-1)-{\gamma}}$) from $m=n={\lceil}{\sqrt{n}{\rceil}$, (a,b) = (0,0), (1,1). The proposed algorithm has proven to improve the performance of the (0,0)-basic Pollard's Rho algorithm by 71.70%.

• Journal of applied mathematics & informatics
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• v.32 no.5_6
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• pp.599-607
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• 2014

In this paper, we investigate the behavior of solutions of the difference equation $$x_{n+1}=\frac{a+x_{n-1}x_{n-k}}{x_{n-1}+x_{n-k}},\;n=0,1,2,{\ldots}$$ where $k{\in}\{1,2\}$, $a{\geq}0$, and $x_{-j}$ > 0, $j=0,1,{\ldots},k$.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.680-683
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• 2002

Bovine aortic endothelial cells(BAEC) produce two variant forms of laminin with a subunit composition of AB1B2 and A'B1B2. Analyses of the intracellular assembly of these subunits revealed that the B1B2 dimer formed first, and that A or A' joined to form the AB1B2 or A'B1B2 trimer. Angiostatic steroids shifted the relative size of the A and A' monomer pool in BAEC, and competition between the A and A' subunits in joining the B1B2 dimer produced AB1B2 and A'B1B2 in different ratios. This result suggests that subunit replacement is the general mechanism for producing laminin variants by various cells for tissue morphogenesis. When laminin subunits in BAEC were cross-linked with dithio-bis-succinimidylpropionate(DSP) and immunoprecipitated with anti-Iaminin antiserum, monomeric A,A',B1 and B2 monomers and the B1B2 dimer migrated as extremely large molecules in sodium dodecyl sulfate gel electrophoresis under nonreducing conditions. When the crosslinking disulfide bonds were cleaved under reducing conditions, they migrated as the usual subunits. This result suggests that molecular chaperones were involved in the process of the assembly and replacement of laminin subunits.

• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.233-239
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• 1994

The characteristics of the bacteriophage resistant Lactococcus lactis subsp. cremoris ATCC 11602-A1, the phage-resistant mutant of Lactococcus lactis subsp. cremoris ATCC 11602, was examined. Electron microscopic study of phage adsorption to A1 revealed that after 10 min. incubation of the host-phage mixture, A1 did not show phage adsorption, and after 60 min. did not show a real burst and the release of new phage particles which could be detected in the mixture of its parent strain and phage. However, the phage adsorption rate of A1 after SDS treatment increased to 98%. Moreover, when the cell walls from A1 and parent strain, and the polysaccharide(PS) and peptidoglycan(PG) of their cell wall were mixed with phage and incubated for 15 min., PS and PG from A1 did not bind phage, but only SD-treated cell wall bound phage, and the cell wall and PS of parent strain bound phage. Both A1 and parent strain treated with 0.2 N HCl-and 5% TCA(100$$C) did not bind phage. The results suggest that the phage receptor is still present in the cell wall of the A1, but a cell wall constituent hydrolyzed by SDS blocks phage adsorption by masking the phage receptor. It also suggests that the phage receptor of parent strain is associated with PS of the cell wall.

• The Pure and Applied Mathematics
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• v.11 no.2
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• pp.167-173
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• 2004

Given vectors x and y in a separable Hilbert space $\cal H$, an interpolating operator is a bounded operator A such that Ax = y. In this article, we investigate Hilbert-Schmidt interpolation problems for vectors in a tridiagonal algebra. We show the following: Let $\cal L$ be a subspace lattice acting on a separable complex Hilbert space $\cal H$ and let x = ($x_{i}$) and y = ($y_{i}$) be vectors in $\cal H$. Then the following are equivalent; (1) There exists a Hilbert-Schmidt operator A = ($a_{ij}$ in Alg$\cal L$ such that Ax = y. (2) There is a bounded sequence {$a_n$ in C such that ${\sum^{\infty}}_{n=1}\mid\alpha_n\mid^2 < \infty$ and $y_1 = \alpha_1x_1 + \alpha_2x_2$ ... $y_{2k} =\alpha_{4k-1}x_{2k}$ $y_{2k=1} = \alpha_{4kx2k} + \alpha_{4k+1}x_{2k+1} + \alpha_{4k+1}x_{2k+2}$ for K $\epsilon$ N.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.1145-1150
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• 2015

Associations of GSTT1, GSTM1 and CYP1A1 gene variants with risk of developing oral cancer were evaluated in this study. A case-control study was conducted in Pashtun population of Khyber Pakhtunkhwa province of Pakistan in which 200 hospital based oral cancer cases and 151 population based healthy controls exposed to similar environmental conditions were included. Sociodemographic data were obtained and blood samples were collected with informed consent for analysis. GSTM1 and GSTT1 were analysed through conventional PCR method while specific RT-PCR method was used to detect CYP1A1 polymorphisms. Results were analyzed for conditional logistic regression model by SPSS version 20. The study shows that patients with either GSTM1 or GSTT1 null genotypes have significantly higher risk of oral cancer (adjusted odds (OR): (3.019 (1.861-4.898) and 3.011(1.865-4.862), respectively), which further increased when either one or both null genes were present in combination (adjusted odds (OR): (3.627 (1.981-6.642 and 9.261 (4.495-19.079), respectively). CYP1A1 rs4646903 gene variants individually showed weak association OR: 1.121 (0.717-1.752); however, in the presence of GSTM1 and/or GSTT1 null genotypes further increasing the association (adjusted odds (ORs): 4.576 (2.038-10.273), 5.593 (2.530-12.362) and 16.10 (3.854-67.260 for GSTM/GSTT null and CYP1A1 wild type, GSTM/GSTT either null and CYP1A1 variant alleles, and all 3 gene polymorphisms combinations, respectively). Our findings suggest that presence of GSTM1 and/or GSTT1 null genotypes along with variant alleles of CYP1A1 may be the risk alleles for oral cancer susceptibility in Pashtun population.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.303-310
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• 2009

Background: Elevated expression of cyclooxygenase-2 (COX-2) and Polo-like kinase-1 (PLK-1) is observed in a wide variety of cancers. Augmented expression of COX-2 and enhanced production of prostaglandin $E_2(PGE_2)$ are associated with increased tumor cell survival and malignancy; COX-2 has been implicated in the control of human non-small cell lung carcinoma (NSCLC) cell growth. PLK-1 siRNA induced the cell death of lung cancer cells and the systemic administration of PLK-1 siRNA/atelocollagen complex inhibited the growth of lung cancer in a liver metastatic murine model. COX-2 and PLK-1 are involved in proliferation and in cell cycle regulation, and there is a significant correlation between their interaction in prostate carcinoma. Methods: In this study, we investigated the pattern of COX-2 and PLK-1 expression in NSCLC, after treatment with IL-1$\beta$, COX-2 inhibitor and PLK-1 siRNA. Results: Expression of PLK-1 was decreased in A549 COX-2 sense cells, and was increased in A549 COX-2 anti-sense cells. Knock out of PLK-1 expression by PLK-1 siRNA augmented COX-2 expression in A549 and NCl-H157 cells. When A549 and NCI-H157 cells were treated with COX-2 inhibitor on a dose-dependent basis, PLK-1 and COX-2 were reduced. However, when the expression of COX-2 was induced by IL-1$\beta$, the production of PLK-1 decreased. Conclusion: These results demonstrate that COX-2 and PLK-1 are regulated and inhibited by each other in NSCLC, and suggest that these proteins have a reverse relationship in NSCLC.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6507-6512
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• 2013

The purpose of this study was to evaluate the associations of CYP1A1 genetic polymorphisms with the risk of developing esophageal cancer (EC). A case-control study was carried out in a Chinese population in which 157 hospital based EC cases and 157 population based healthy controls with 1:1 match by age and sex were included. PCR based restriction fragment length polymorphisms (PCR-RFLP) were used to detect genotypes in case and control groups. For the CYP1A1 Ile/Val polymorphism, comparing with wild genotype Ile/Ile, both the heterozygote genotype Ile/Val and the combined variant genotype Ile/Val+Val/Val increased the risk of esophageal cancer (OR: 2.05, 95%CI: 1.19-3.54, OR: 1.86, 95%CI: 1.11-3.12). No significant association was found between the CYP1A1 MspI polymorphism and EC. According to analysis of combined genotypes, the TC/AG combined genotype which contained both variant alleles of these two polymorphisms increased the risk of developing EC (OR: 2.12, 95%CI: 1.16-3.85). Our results suggested that genetic polymorphisms of CYP1A1 may increase the susceptibility to EC.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.6
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• pp.525-532
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• 2021

We have investigated the relative roles of α₁-adrenoceptors and purinoceptors in contractions to low and high frequency stimulation of the mouse vas deferens, in terms of the time course of responses. In separate experiments, isometric contractile responses were obtained to 10 pulses at 1 Hz and 40 pulses at 10 Hz. Responses to 1 Hz stimulation consisted of a series of discrete peaks. The α_1A-adrenoceptor antagonist RS100329 (10^-9M-10^-7M) significantly reduced the response to the first pulse, the α_1D-adrenoceptor antagonist BMY7378 (10^-7M-10^-6M) significantly reduced the response to the first two pulses, and the non-selective α₁-adrenoceptor antagonist prazosin (10^-8M) reduced the response to the first 4 pulses at 1 Hz. Responses to 10 Hz stimulation consisted of an early peak response and a maintained plateau response. RS100329 significantly reduced the peak response but did not significantly affect the plateau response. Prazosin, significantly reduced both the peak and plateau responses. The α_1A-adrenoceptor antagonist RS17053 in high concentrations reduced mainly the plateau response leaving a clear early peak response. The plateau response of contraction was almost abolished by the purinoceptor antagonist suramin. These results suggest that there is a relatively minor early α_1D-adrenoceptor and a larger early α_1A-adrenoceptor component to stimulationevoked contractions of mouse vas deferens, but the major α₁-adrenoceptor component is revealed by prazosin to be α_1B-adrenoceptor mediated. α_1B-Adrenoceptor activation probably facilitates contractions mediated by other α₁-adrenoceptors and by purinoceptors. These results suggest that combined non-selective α₁-adrenoceptor blockade, particularly α_1B-adrenoceptor blockade, in addition to P2X1-purinoceptor blockade is useful in reducing male fertility.

• Journal of agricultural medicine and community health
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• v.38 no.4
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• pp.217-228
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• 2013

Objective: This study was performed to identify associations between the practice of health behaviors and awareness of metabolic syndrome (MetS) among adults aged 19 to 64 years in the Gwangju-Jeonnam area. Methods: This study utilized data from the 2010 Community Health Survey (CHS). Health behaviors considered in this study were smoking, alcohol drinking, physical activity, low-salt diet, and perception of stress. The index for the health behaviors was calculated as the sum of the practice of each health behavior (range: 0-5). The analysis was weighted with a complex sampling design, and the chi-square test and multiple logistic regression analysis were used to identify the association between the practice of health behaviors and awareness of MetS. Results: A total of 19.8% of the population were aware of MetS. The perception of MetS was statistically significantly associated with healthy behaviors, including nonsmoking (aOR = 1.33, 95% CI = 1.14-1.56), non-high-risk drinking (aOR = 1.54, 95% CI = 1.27-1.88), engagement in physical activity (aOR = 1.48, 95% CI = 1.28-1.72), and a low-salt diet (aOR = 1.30, 95% CI = 1.13-1.51). The ORs of the perception of MetS were significantly higher in patients with a health behavior index of 2 to 3 (aOR = 1.64, 95% CI = 1.01-2.66) and in those with an index of ${\geq}4$ (aOR = 2.47, 95% CI = 1.51-4.04) than in those with an index of 0. Among all health behaviors, physical activity had the highest OR for the perception of MetS (aOR = 1.50, 95% CI = 1.29-1.74). Conclusions: This study revealed associations between health behaviors, especially physical activity, and awareness of MetS. Therefore, integrated health promotion programs may be needed to enhance awareness of MetS and to effectively prevent MetS and non-communicable diseases.