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Effects of Apolipoprotein A-I on Apoptosis and Cytokine Production in Human Neutrophils (인간 호중구의 세포사멸과 시토카인 분비에 대한 아포지방단백 A-I의 영향)

  • Kang, Hyung-Kon;Choi, Jae-Hyung;Huh, Jae-Taeck
    • Journal of Life Science
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    • v.21 no.1
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    • pp.22-30
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    • 2011
  • Apolipoprotein A-I (apoA-I) has anti-inflammatory and anti-oxidative properties. This study was designed to investigate whether apoA-I affects apoptosis and cytokine production of human blood neutrophils in an in vitro culture system. Spontaneous apoptosis of neutrophils was significantly delayed by apoA-I. In addition, high density lipoprotein containing apoA-I also delayed apoptosis of neutrophils. Apoptosis of neutrophils was inhibited by anti-scavenger receptor type B-I antibodies. The amounts of interleukin-8, interferon (IFN)-inducible protein 10 (IP-10), and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) in the supernatants of cultured neutrophils treated with apoA-I were significantly increased. Combined treatment of neutrophils with IFN-$\gamma$ and apoA-I produced higher amounts of IP-10 and TNF-$\alpha$ than did treatment with IFN-$\gamma$ or apoA-I alone. The present study reveals that apoA-I activates neutrophils to produce cytokines and delays spontaneous apoptosis of neutrophils. These findings suggest that apoA-I, although a well-known negative acute-phase protein, has a pro-inflammatory effect in neutrophils.

The Effect of the IGF-I treated Gingival and Periodontal Ligament Fibroblast on Osteoblasts (IGF-I으로 처리한 치은 및 치주인대 섬유모세포가 골모세포에 미치는 영향)

  • Kim, Mi-Jeong;Yang, Won-Sik
    • The korean journal of orthodontics
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    • v.31 no.6 s.89
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    • pp.589-600
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    • 2001
  • Insulin-like growth factor I (IGF-I) has the local tissue regulating actions. In bone, IGF-I increases the replication of osteoblastic lineage, probably preosteoblasts, and enhances osteoblastic collagen synthesis and matrix composition rates. The purpose of this study was to investigate the local regulatory effect of IGF-I on periodontium totally, both in an autocrine and paracrine manner. To examine the effect of IGF-I directly on osteoblast (OB) of test rats, and indirectlv on OB via periodontal ligament fibroblast (PDLF), and the effect of gingival fibroblast (GF) on OB via cellular paracrine manner for the understanding of humoral action of adjacent tissue, GF and PDLF were obtained from male Sprague-Dawley rats of six to eight weeks of age. OB was obtained iron frontal and parietal calvarial bone of Sprague-Dawley 21day-old-fetus. After each tell was Incubated 24 hours, for collecting conditioned medium, different concentrations of IGF-I (1,10,100 ng/ml,1ml/well) was adding in the GF, PDLF cells, and the supernatant from these cultures was put into the primary OB culture with $1{\times}10^4$cell/ml/well. The experimental group was divided into six groups control OB, IGF-I treated OB, OB culture with conditioned medium from PDLF, OB culture with conditioned medium from IGF-I treated PDLF, OB culture with conditioned medium from GF, OB culture with conditioned medium from IGF-I treated GF. After final IGF-I treatment, OB was Incubated for 24 hours, and alkaline phosphatase activity assay, BMP expression, cell proliferation measurement using MTT assay, total protein measurement, Collagen synthesis assay using western blot, and examination of bone nodule synthesis were done. Alkaline phosphatase expressions were increased in the group of PDLF-IGF-I supernatant treatment. Direct IGF-I treatment with concentrations of 100ng/m1 showed increased viable tell number measured by MTT assay. And IGF-I treatment did not increase total protein amount. The entire experimental group showed BMP2, 4 expression in western blot, and there was no significant difference between control and experimental groups. These results suggested that supernatant from PDLF effects on increasing cellular activities of OB regardless of IGF-I, and at high concentration, IGF-I increases OB tell proliferation.

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Numerical Solution for Nonlinear Klein-Gordon Equation by Using Lagrange Polynomial Interpolation with a Trick (라그란제 보간을 사용한 비선형 클라인 고든 미분방적식의 수치해)

  • Lee In-Jung
    • The KIPS Transactions:PartA
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    • v.11A no.7 s.91
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    • pp.571-576
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    • 2004
  • In this paper, by using Lagrange polynomial interpolation with a trick such that for $f(x)^{3}$ we shall use $f(x_i)^{3}I_i(x)^{3}$ instead of $I(x)^{3}$ where $I{x}{\;}={\;}\sum_{i}^{f}(x_i)I_i(x)$. We show the convergence and stability and calculate errors. These errors are approximately less than $C(\frac{1}{N})^{N-1} hN(N-1)(\frac{N}{2})^{N-1} /(\frac{N}{2})!$ where N is a polynomial degree.

Annexin I Stimulates Insulin Secretion through Regulation of Cytoskeleton and PKC Activity

  • Kang, Na-Na;Won, Jong-Hak;Park, Young-Min
    • Animal cells and systems
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    • v.13 no.1
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    • pp.17-23
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    • 2009
  • In previous studies, we found that Annexin I (Anx I) was co-secreted with insulin in response to glucose, and that extracellular Anx I stimulated the release of insulin via the Anx I binding site in rat pancreatic islets and the &-cell line. However, the role that Anx I plays in the insulin secretion was not established. Therefore, in this study, we evaluated the insulin secretion pattern in response to Anx I and the involvement of the cytoskeleton or PKC in Anx Istimulated insulin secretion in MIN6N8a cells. The peak time of insulin secretion in response to Anx I treatment corresponded with the second phase insulin secretion by glucose in the perifused pseudoislets. In addition, Anx I-stimulated insulin secretion was not affect by readily releasable pool depletion. Taken together, these findings indicate that Anx I treatment was associated with movement of the reserve pool of insulin. Furthermore, Anx I-stimulated insulin secretion was attenuated by treatment with a microfilament inhibitor, cytochalasin B, as well as by PKC down regulation. These results indicate that Anx I may be a regulator of second phase insulin secretion.

A Novel Compensation Scheme for I/Q Mismatch in an OFDM Direct-Conversion Architecture (OFDM 전송방식 기반의 Direct-Conversion 수신기에서 I/Q 불균형 보상을 위한 새로운 방법 제안)

  • Bae, Jung-Hwa;Park, Jin-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.12C
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    • pp.1265-1272
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    • 2006
  • This paper proposes a compensation method that can alleviate the problem of I/Q mismatch generated in the direct-conversion receiver of OFDM systems. In the proposed method, the amount of I/Q mismatch is estimated using null-carriers in transmitted signals, and it is subtracted from received symbols to suppress I/Q mismatch effects. Simulations show experiments that the proposed method can effectively eliminate the I/Q mismatch effects.

Analyzing the Impact of Supply Noise on Jitter in GBPS Serial Links on a Merged I/O-Core Power Delivery Network

  • Tan, Fern-Nee;Lee, Sheng Chyan
    • Journal of the Microelectronics and Packaging Society
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    • v.20 no.4
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    • pp.69-74
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    • 2013
  • In this paper, the impact of integrating large number of I/O (Input-Output) and Core power Delivery Network (PDN) on a 6 layers Flip-Chip Ball Grid Array (FCBGA) package is investigated. The impact of core induced supply noise on high-speed I/O interfaces, and high-speed I/O interface's supply noise coupling to adjacent high-speed I/O interfaces' jitter impact are studied. Concurrent stress validation software is used to induce SSO noise on each individual I/O interfaces; and at the same time; periodic noise is introduced from Core PDN into the I/O PDN domain. In order to have the maximum coupling impact, a prototype package is designed to merge the I/O and Core PDN as one while impact on jitter on each I/O interfaces are investigated. In order to understand the impact of the Core to I/O and I/O to I/O noise, the on-die noise measurements were measured and results were compared with the original PDN where each I/O and Core PDN are standalone and isolated are used as a benchmark.

GOODNESS-OF-FIT TEST USING LOCAL MAXIMUM LIKELIHOOD POLYNOMIAL ESTIMATOR FOR SPARSE MULTINOMIAL DATA

  • Baek, Jang-Sun
    • Journal of the Korean Statistical Society
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    • v.33 no.3
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    • pp.313-321
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    • 2004
  • We consider the problem of testing cell probabilities in sparse multinomial data. Aerts et al. (2000) presented T=${{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2$ as a test statistic with the local least square polynomial estimator ${{p}_{i}}^{*}$, and derived its asymptotic distribution. The local least square estimator may produce negative estimates for cell probabilities. The local maximum likelihood polynomial estimator ${{\hat{p}}_{i}}$, however, guarantees positive estimates for cell probabilities and has the same asymptotic performance as the local least square estimator (Baek and Park, 2003). When there are cell probabilities with relatively much different sizes, the same contribution of the difference between the estimator and the hypothetical probability at each cell in their test statistic would not be proper to measure the total goodness-of-fit. We consider a Pearson type of goodness-of-fit test statistic, $T_1={{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2/p_{i}$ instead, and show it follows an asymptotic normal distribution. Also we investigate the asymptotic normality of $T_2={{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2/p_{i}$ where the minimum expected cell frequency is very small.

Effects of camptothecin on the expression of DNA topoisomerase I and c-myc in HL-60 human leukemia cells (HL-60 사람 백혈병 세포에서 camptothecin이 DNA topoisomerase l과 c-myc의 발현에 미치는 영향)

  • 정인철;정대성;류경자;박장수;조무연
    • Journal of Life Science
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    • v.10 no.6
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    • pp.621-629
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    • 2000
  • Camptothecin (CPT) is an antitumor alkaloid that has been isolated from the Chinese tree, Camptotheca acuminata. The cytotoxicity of CPT has been correlated to its inhibition of DNA topoisomerase (Topo) I by stabilizing drug-enzyme-DNA “cleavable complex" resulting in DNA single-strand breaks and DNA-protein crosslinks. This studies were designed to elucidate whether CPT regulates Topo I mediated by CPT in DNAs containing c-myc protooncogene. We have conducted experiments on Topo I purification, pUC-MYC I cloning and Topo I assay using electrophoresis, quantitative RT-PCR and Northern blotting techniques. CPT ingibited the relaxation activity of Topo I in pUC19 DNA at various concentrations (1-1000 $\mu$M), while it enhanced the cleavage of Topo I in the pUC-MYC I by forming a cleavable complex at relatively high concentrations (100-1000 $\mu$M). In HL-60 cells treated with CPT, the expression of c-myc gene was decreased over that in the control group with no changes in the expression of Topo I mRNA. Our results suggest that Topo I is the target of CPT cytotoxicity but it does not affect Topo I extression, and the suppression of c-myc mRNA expression by CPT is due to c-myc damage resulted from formation of a cleavable complex with CPT. CPT.

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FUNCTIONAL EQUATIONS ASSOCIATED WITH INNER PRODUCT SPACES

  • Park, Choonkil;Huh, Jae Sung;Min, Won June;Nam, Dong Hoon;Roh, Seung Hyeon
    • Journal of the Chungcheong Mathematical Society
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    • v.21 no.4
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    • pp.455-466
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    • 2008
  • In, [7], Th.M. Rassias proved that the norm defined over a real vector space V is induced by an inner product if and only if for a fixed integer $n{\geq}2$ $$n{\left\|{\frac{1}{n}}{\sum\limits_{i=1}^{n}}x_i{\left\|^2+{\sum\limits_{i=1}^{n}}\right\|}{x_i-{\frac{1}{n}}{\sum\limits_{j=1}^{n}x_j}}\right\|^2}={\sum\limits_{i=1}^{n}}{\parallel}x_i{\parallel}^2$$ holds for all $x_1,{\cdots},x_{n}{\in}V$. Let V,W be real vector spaces. It is shown that if a mapping $f:V{\rightarrow}W$ satisfies $$(0.1){\hspace{10}}nf{\left({\frac{1}{n}}{\sum\limits_{i=1}^{n}}x_i \right)}+{\sum\limits_{i=1}^{n}}f{\left({x_i-{\frac{1}{n}}{\sum\limits_{j=1}^{n}}x_i}\right)}\\{\hspace{140}}={\sum\limits_{i=1}^{n}}f(x_i)$$ for all $x_1$, ${\dots}$, $x_{n}{\in}V$ $$(0.2){\hspace{10}}2f\(\frac{x+y}{2}\)+f\(\frac{x-y}{2} \)+f\(\frac{y}{2}-x\)\\{\hspace{185}}=f(x)+f(y)$$ for all $x,y{\in}V$. Furthermore, we prove the generalized Hyers-Ulam stability of the functional equation (0.2) in real Banach spaces.

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An Empirical Study on the Factors that Affect the Continuous Use Intention of i-PIN (아이핀(i-PIN)의 지속적 사용의도에 영향을 미치는 요인에 관한 실증적 연구)

  • Im, Hyuk;Kim, Tae-Sung
    • Journal of Information Technology Applications and Management
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    • v.22 no.4
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    • pp.159-179
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    • 2015
  • In 2005, Korean government created the Internet Personal Identification Number (i-PIN) for a new online personal identification system to protect citizens' personal information against criminal abuse. However, i-PINs have not been widely in use over a decade. Although many people joined the i-PIN service, its actual use rate has been low. This study intends to identify the factors necessary to boost the continuous use of i-PINs. It was shown that government support and perceived security had a positive effect on the perceived ease of use and perceived usefulness of the i-PIN, respectively. Perceived security also directly affected the continuous use intention of the i-PIN. The perceived ease of use significantly affected the perceived usefulness, but it did not affect the intention to continuously use the i-PIN. The factor that had the most significant influence on the continuous use intention of the i-PIN was perceived usefulness. To increase the i-PIN use rate, Korean government must reduce users' anxiety through strict security functions, and must attempt to help people use the i-PIN easily.