Showing papers by "Chung-Ang University published in 2000"
TL;DR: Immediate intervention for acute alkali burns with AM as a temporary patch promotes wound healing by inhibiting proteinase activity and PMNs infiltration.
331 citations
TL;DR: In this paper, thin film composite membranes were prepared by the interfacial polymerization with various acyl chloride solutions and amine solutions containing poly(m-aminostyrene), (PmAS).
178 citations
TL;DR: Results indicate that boldine may exert an inhibitory effect on STZ-induced oxidative tissue damage and altered antioxidant enzyme activity by the decomposition of reactive oxygen species and inhibition of nitric oxide production and by the reduction of the peroxidation-induced product formation.
164 citations
TL;DR: The present study strongly suggests interspecific cross-hybridization between the two species coexisting in Korea, and indicates an existence of different alleles at the loci.
145 citations
TL;DR: Infertile women showed significant increases intrait anxiety and depressive symptoms than the fertile women, and demographic factors such as religion and husband cooperation were not related to the experience of stress.
Abstract: Purpose: The objectives of this study were to compare average stress levels in infertile women to fertile women, to determine the stress levels whether the patients was pregnant or not pregnant, and to examine for a cross-section of infertile patients in different stages of medical investigation for the infertility. Methods: One hundred thirty-eight women receiving medical treatment for infertility attended the program. The State Trait Anxiety Inventory (STAI) and the Beck Depression Inventory (BDI) ofperceived stress associated with the infertility was the outcome measure. Results: Infertile women showed significant increases in trait anxiety and depressive symptoms than the fertile women. Anxiety and depression in the in vitro fertilization (IVF)-failed women were significantly higher than the IVF-success women. According to the duration of infertility, STAI and BDI were moderately elevated in the first stage (< 3 year). There was a trend of a decreasing psychological stress with an advanced infertility duration. On depression scales, the intermediate and final duration of infertility patients showed less symptomatology than the first-stage patients. Contrary to the expectation, demographic factors such as religion and husband cooperation were not related to the experience of stress. Conclusions: We must pay an attention to the infertile patient, especially from the initial infertility workup. We recommend psychological counselling for IVF-failed patients.
140 citations
TL;DR: In this article, the authors outline the indigenous psychologies approach within the context of three research traditions in cross-cultural psychology: the universalist, contextualist, and integrationist approaches.
Abstract: This article outlines the indigenous psychologies approach within the context of three research traditions in cross-cultural psychology: the universalist, contextualist, and integrationist approaches. The first section outlines the limitations of the universalist and contextualist approaches. The second section overviews the two integrationist approaches: the derived etics approach and the indigenous psychologies approach. In comparison to the former approach, the indigenous psychologies approach advocates a bottom-up, model-building paradigm that examines generative capabilities of human beings. It investigates human actions that occur in meaningful context. In this transactional approach, human consciousness, intentions, and goals are central aspects of the research design.
140 citations
TL;DR: This study provides the first evidence, to the authors' knowledge, for occurrence and gravitropic activity of BRs in plant roots and indicates that brassinosteroids (BRs) might be involved in auxin-mediated processes for the grav itropic response.
Abstract: Exogenously applied brassinolide (BL, 10 −9 –10 −5 m) increased gravitropic curvature in maize ( Zea mays ) primary roots. The BL-enhanced gravitropic curvature was clearly promoted in the presence of indole-3-acetic acid (IAA, 10 −10 –10 −8 m), indicating that BL is interactive with IAA during the gravitropic response. The interactive effect between BL and IAA was completely diminished by treatment of p -chlorophenoxy isobutric acid, an auxin action antagonist. The activation of the gravitropic response by BL in the absence and in the presence of IAA was nullified by application of 2,3,5-triiodobenzoic acid, a polar auxin transport inhibitor. The data indicate that brassinosteroids (BRs) might be involved in auxin-mediated processes for the gravitropic response. Gas chromotography-selected ion-monitoring analysis revealed that maize primary roots contained approximately 0.3 ng g −1 fresh weight castasterone as an endogenous BR. Exogenously applied castasterone also increased the gravitropic response of maize roots in an IAA-dependent manner. This study provides the first evidence, to our knowledge, for occurrence and gravitropic activity of BRs in plant roots.
134 citations
TL;DR: The authors compare three research traditions in psychology: universalist, contextualist, and integrationist approaches, concluding that the search for universals should include the content and context of culture and rejecting absolute universalism and relativism.
Abstract: This paper compares indigenous, cultural, and cross-cultural psychology by examining their theoretical, conceptual, and epistemological foundations. They have been influenced by the three research traditions in psychology: (1) universalist, (2) contextualist, and (3) integrationist approaches. The goal of the universalist approach is to test and verify universality of existing psychological theories. Cultural psychologists, in contrast, point out that presumed universals are actually Western impositions and not universals. They affirm the contextualist approach and argue that every culture possesses its own unique characteristics, and they should be understood from within the culture. Integrationists argue that search for universals should include the content and context of culture, and they reject absolute universalism and relativism. In cross-cultural psychology, two integrationist approaches can be identified: the derived etic approach (Berry, 1980) and the indigenous psychologies approach (Kim, Park, & Park, 1999). In the derived etic approach, researchers adapt and integrate existing theories to fit local knowledge. Indigenization as articulated by Sinha (1997) represents this approach. In the indigenous psychologies approach, the primary goal is to understand how people think, feel, and behave in a particular context. It advocates a bottom-up model-building paradigm that examines the generative capabilities of human beings. Detailed analysis of the indigenous psychologies approach is provided.
120 citations
TL;DR: In this article, the hydrodynamic properties of a pair of long floating pontoon breakwaters of rectangular section are investigated theoretically, where the structures are partially restrained by linear symmetric moorings fore and aft.
117 citations
TL;DR: This letter is concerned with a frequency offset estimation technique for OFDM based transmission systems that utilizes a repetitive signal structure inside of a OFDM symbol which is used to enlarge the range and increase the accuracy of offset estimation.
Abstract: This letter is concerned with a frequency offset estimation technique for OFDM based transmission systems. The frequency estimation technique utilizes a repetitive signal structure inside of a OFDM symbol which is used to enlarge the range and increase the accuracy of offset estimation. Also, an averaged decision-directed channel estimation (ADDCE) technique suitable for burst data is proposed.
105 citations
18 Sep 2000
TL;DR: An efficient channel estimation technique for orthogonal frequency-division multiplexing (OFDM) systems with transmitter diversity using "comb-type" training symbols is proposed, reduced dramatically, compared with the previous minimum mean-squared error technique.
Abstract: We propose an efficient channel estimation technique for orthogonal frequency-division multiplexing (OFDM) systems with transmitter diversity. The proposed technique estimates uniquely all channel frequency responses needed in space-time coded OFDM systems using "comb-type" training symbols. The computational complexity of the proposed technique is reduced dramatically, compared with the previous minimum mean-squared error (MMSE) technique, due to the all the processing being done in the frequency-domain. Also, several other techniques for mitigating the random noise effect and tracking channel variation are discussed to further improve the performance of the proposed approach. The performances of the proposed approach are demonstrated by computer simulation for mobile wireless channels.
TL;DR: The cationic lipid emulsion/DNA complex has physicalstability and serum resistant properties for gene transfer and facilitated the transfer of DNA in the presence of up to 90% serum.
Abstract: Purpose. To develop a non-viral gene delivery system in the form ofan oil-in-water (o/w) lipid emulsionMethod. Cationic lipid emulsions were formulated with soybean oil,1,2-dioleoyl-sn-glycero-3-trimethylammonium-propane (DOTAP) as acationic emulsifier and other co-emulsifiers. The physicalcharacteristics of the lipid emulsion and the emulsion/DNA complex weredetermined. The in vitro transfection efficiency of the emulsion/DNAcomplex was determined in the presence of up to 90% serum.
TL;DR: This article analyzed the nature of epistemological beliefs about learning (learning beliefs) in Korea and the United States and found that US students' learning beliefs are significantly related with the independent self-construal, but not with the interdependent selfconstruality.
Abstract: The present study analyzed the nature of epistemological beliefs about learning (learning beliefs) in Korea and the United States. Learning beliefs are implicit assumptions held by learners about the source and certainty of knowledge and the ways to obtain knowledge. For the comparative analysis of both the model and the nature of learning beliefs across two countries that differ in emphasis on individualism and collectivism, two attempts were made. First, Jehng, Johnson, and Anderson's (1993) study was replicated with university students from the US (N=496) and Korea (N=487). Second, the relationship between US students' learning beliefs and the two aspects of their self-construal (independent and interdependent) was analyzed by using a scale developed by Singelis (1994) which measures cultural orientation of individualism and collectivism at the individual level. Factor analyses of the US sample confirmed the conceptual model proposed by Jehng et al. The factor structure of the Korean sample, however, showed significant variation reflecting the collectivistic values of Korea. MANCOVA indicated that the two developmental factors, age and the amount of formal education, were related with American students' beliefs, but they were not with those of Korean students. MANCOVA revealed that US students' beliefs are significantly related with the independent self-construal, but not with the interdependent self-construal. The differences between the two samples in terms of the impact of formal education and self-construal on learning beliefs will be further discussed by focusing on the cultural differences between the two countries.
TL;DR: The acetone extract of the roots of Rhodiola sachalinensis has furnished six phenolic compounds which exhibited significant scavenging effects against DPPH free radical.
Abstract: The acetone extract of the roots of Rhodiola sachalinensis has furnished six phenolic compounds which exhibited significant scavenging effects against DPPH free radical. The structures of these compounds were identified and determined as gallic acid (1), (-)-epigallocatechin 3-O-gallate (2), kaempferol (3), kaempferol 7-O-alpha-L-rhamnopyranoside (4), herbacetin 7-O-alpha-L-rhamnopyranoside, (5) and rhodiolinin (6) by physico-chemical and spectral evidences.
TL;DR: The results suggest that EB1089 inhibits growth of NCI‐H929 cells via G1 cell cycle arrest as well as apoptosis by activating p38 kinase and suppressing ERK activity.
Abstract: EB1089, a novel 1,25-dihydroxyvitamin D3 analogue, has been known to have potent antiproliferative properties in a variety of malignant cells both in vitro and in vivo. In the present study, we analysed the effect of EB1089 on NCI-H929 human myeloma cells. EB1089 inhibited cell growth of NCI-H929 and efficiently induced the G1 phase arrest of the cell cycle in a dose-dependent manner. We could also detect apoptosis in NCI-H929 cells exposed to EB1089 (1 x 10-7 M for 72 h) using the sub-G1 group of the cell cycle by FACS and annexin V binding assays. Induction of apoptosis by EB1089 was associated with down-regulation of the Bcl-2 protein without change of the Bax protein. Regarding caspase activity, which plays a crucial role in apoptosis, EB1089-treated NCI-H929 cells revealed an increased activity of caspase 3 protease accompanied by degradation of the PARP protein in a dose- and time-dependent manner. In addition, EB1089 caused the down-regulation of p44 extracellular signal-related kinase (ERK) activity and up-regulation of the p38 kinase activity during apoptosis of NCI-H929 cells. These results suggest that EB1089 inhibits growth of NCI-H929 cells via G1 cell cycle arrest as well as apoptosis by activating p38 kinase and suppressing ERK activity.
TL;DR: The proposed algorithm for adaptive beamforming in the OFDM system is derived by calculating the pilot error signals in the frequency domain, transforming the frequency-domain error signals into time- domain error signals, and updating the filter coefficients of the adaptive beamformer in the direction of minimizing the MSE.
Abstract: This paper presents an adaptive beamforming algorithm for an OFDM system with an adaptive array antenna. The proposed algorithm for adaptive beamforming in the OFDM system is derived by (1) calculating the pilot error signals in the frequency domain, (2) transforming the frequency-domain error signals into time-domain error signals, (3) updating the filter coefficients of the adaptive beamformer in the direction of minimizing the MSE. The convergence behavior and performance improvement of the proposed approach are investigated through computer simulation by applying it to the conventional OFDM system.
TL;DR: Two cases in which a tuberculous aneurysm of the abdominal aorta was successfully repaired using endovascular stent grafts are reported, one of which is a 42-year-old woman with a large suprarenal abdominal aortsm and a right psoas abscess.
Abstract: Tuberculous aneurysm of the aorta is exceedingly rare. To date, the standard therapy for mycotic aneurysm of the abdominal aorta has been surgery involving in-situ graft placement or extra-anatomic bypass surgery followed by effective anti-tuberculous medication. Only recently has the use of a stent graft in the treatment of tuberculous aortic aneurysm been described in the literature. We report two cases in which a tuberculous aneurysm of the abdominal aorta was successfully repaired using endovascular stent grafts. One case involved is a 42-year-old woman with a large suprarenal abdominal aortic aneurysm and a right psoas abscess, and the other, a 41-year-old man in whom an abdominal aortic aneurysm ruptured during surgical drainage of a psoas abscess.
TL;DR: A middle-aged man with Nutcracker syndrome accompanied by renal enlargement, persistent haematuria, proteinuria and hypertension with a new intravascular stent is satisfactorily treated.
Abstract: The clinical syndrome caused by impingement of the left renal vein (LRV ) between the superior mesenteric artery (SMA) and abdominal aorta has been termed Nutcracker syndrome [1]. Although often asymptomatic, it may result in varicocele, ovarian vein syndrome, haematuria, flank or abdominal pain, LRV hypertension, and pelviureteral varices. Surgical approaches for Nutcracker syndrome include nephrectomy, nephropexy, renocaval reimplantation, or auto-transplantation. We satisfactorily treated a middle-aged man with Nutcracker syndrome accompanied by renal enlargement, persistent haematuria, proteinuria and hypertension with a new intravascular stent.
TL;DR: The parasite Clonorchis sinensis was determined to utilize a large amount of external glucose to carry its energy metabolism, and PGK, a glycolytic enzyme found in many parasites, has been identified as one of the candidate molecules distinguished from human counterparts for vaccine and drug developments.
TL;DR: The authors empirically examined several major determinants of American Depositary Receipts (ADRs) and their underlying stock returns for the period of 1990-1996 and discuss implications for international diversification and market segmentation.
TL;DR: The results suggest that EB1089 can inhibit the proliferation of human myeloma cells, especially NCI-H929 cells, via a G(1) block in association with the induction of p27 and the reduction of CDK2 activity.
TL;DR: It was concluded that amitriptyline blocked the two types of Na(+) channels in rat sensory neurons by modulating the activation and the inactivation kinetics.
TL;DR: Two known diarylheptanoids, oregonin and hirsutanonol, showed significant inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cyclooxygenase-2 (COX-2) expression in immortalized human breast epithelial MCF10A cells.
Abstract: Two known diarylheptanoids, oregonin (1), (5S)-1, 7-bis-(3, 4-dihydroxyphenyl)-heptane-3-one-5-O-β-D-xylopyranoside and hirsutanonol (2), (5S)-1, 7-bis-(3, 4-dihydroxyphenyl)-5-hydroxyheptane-3-one isolated from the bark of Alnus hirsuta var. sibirica, showed significant inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cyclooxygenase-2 (COX-2) expression in immortalized human breast epithelial MCDF10A cells.
TL;DR: Menopause itself is associated with the elevation of HDL-C level, and the postmenopausal increase of coronary artery disease is not related to post menopause change of HDL -C level.
Abstract: It has been generally accepted that high density lipoprotein cholesterol (HDL-C) level decreases with menopause in women. However, recent reports show different results. There is very little data concerning perimenopausal women. To verify these findings, lipids and lipoprotein(a) [Lp(a)] levels were compared among pre-, peri- and postmenopausal women of similar mean ages. Postmenopausal women had higher HDL-C levels than premenopausal women (p<0.001) and there was no difference between peri- and postmenopausal women. LDL-C level in perimenopausal women was lower than in postmenopausal women (p<0.001) and higher than in premenopausal women with borderline significance (p=.051). Total cholesterol levels showed stepwise elevation from premenopause to postmenopause. Perimenopausal women had lower Lp(a) levels than postmenopausal women (p<0.0005) and similar levels to premenopausal women. Lp(a) levels between 0.1 to 10.0 mg/dL were the most prevalent in pre- and perimenopausal women, and those between 10.1 to 20.0 mg/dL in postmenopausal women. In conclusion, menopause itself is associated with the elevation of HDL-C level, and the postmenopausal increase of coronary artery disease is not related to postmenopausal change of HDL-C level. Perimenopausal status, although transient, may favor Lp(a) and lipid profiles for delaying atherosclerosis.
TL;DR: The results suggest that ginsenosides produce antinociceptive effects through their action at the spinal and/or supraspinal site(s), not at nociceptors in the periphery, and that these effects are not mediated by opioid receptors.
TL;DR: F Forced expression of urea cycle enzymes in the CHO cells revealed that both the expression of CPS I and OTC can reduce the accumulation of ammonium ion in the culture media.
TL;DR: An expression plasmid, pHis-Tyrosinase, which contains the entire coding sequence except the signal sequence of a human tyrosin enzyme was constructed and expressed in Escherichia coli and had the same electrophoretic mobility as the native enzyme from human melanoma cell.
Abstract: To carry out biochemical characterizations of human tyrosinase and to provide an unlimited source of the enzyme for further study, an expression plasmid, pHis-Tyrosinase, which contains the entire coding sequence except the signal sequence of a human tyrosinase was constructed and expressed in Escherichia coli . The expressed enzyme was simply purified by an immobilized metal affinity chromatography. The recombinant enzyme had the same electrophoretic mobility as the native enzyme from human melanoma cell and cross-reacted with the polyclonal antibody raised against the native enzyme. The recombinant enzyme retained its catalytic function with both hydroxylating and oxidative activities. K m values for l -tyrosine and l -3,4-dihydroxy-phenylalanine of the recombinant enzyme were 0.17 and 0.36 mM, respectively. The activity of the recombinant enzyme was optimal at pH 7.5. Glutathione notably inhibited the enzymatic activity. This work is a further enzymatic characterization of human tyrosinase.
Journal Article•
TL;DR: A chain reaction, the production of superoxide radicals and functional impairment of eNOS may be a major cause of the functional impairment in the early stages of hypercholesterolemia.
Abstract: We have done consecutive studies to investigate the effects of impaired lipid metabolism on the contractile and relaxation response of cavernous smooth muscles and to elucidate its pathogenesis: 1) incidence of hyperlipidemia in impotent patients; 2) erection response to intracavernous injection of papaverine in impotent patients with hyperlipidemia; 3) relaxation responses of isolated cavernosal smooth muscles to endothelium-independent and endothelium-dependent vasodilators in impotent patients with hypercholesterolemia or hypertriglyceridemia; 4) involvement of superoxide radical in the impaired endothelium-dependent relaxation of cavernous smooth muscle in hypercholesterolemic rabbits; 5) effects of isolated lipoproteins and triglyceride, combined oxidized LDL plus triglyceride, and combined oxidized LDL plus HDL on contractile and relaxation response of rabbit cavernous smooth muscles; 6) involvement of e-NOS in the impaired endothelium-dependent relaxation of cavernous smooth muscle in hypercholesterolemic rabbit. Hypercholesterolemia may cause impairment of endothelium-dependent relaxation. Oxidized LDL is the major causative cholesterol of the impaired relaxation response. A chain reaction, the production of superoxide radicals and functional impairment of eNOS may be a major cause of the functional impairment in the early stages of hypercholesterolemia.
TL;DR: It is suggested that exposure to MFs inhibits the increase of pain thresholds at night time and produces hyperalgesia at daytime with the involvement of opioid and benzodiazepine systems.
Abstract: 1 We studied the effects of extremely low frequency (ELF, 60 Hz) magnetic fields (MFs) on pain thresholds using the hot plate test. The implication of opioid and benzodiazepine system in the MFs-induced alteration of pain thresholds was also studied.
2 There was an increase at night time and a decrease at daytime of pain thresholds in normal mice. Exposure of MFs (24 h, 20 gauss (G)) inhibited the increase of pain thresholds at night time and even produced hyperalgesia at daytime.
3 The increase of pain thresholds induced by melatonin at daytime was inhibited by exposure to MFs (24 h, 20 G) or opioid antagonist naloxone. The MFs and naloxone synergically inhibited hypoalgesia produced by melatonin. The hyperalgesia at daytime after MFs exposure was potentiated by the benzodiazepine agonist, diazepam, and inhibited by the benzodiazepine antagonist, flumazenil. There was no significant difference in all rotarod performance we tested.
4 From these results, it is suggested that exposure to MFs inhibits the increase of pain thresholds at night time and produces hyperalgesia at daytime with the involvement of opioid and benzodiazepine systems.
TL;DR: In this article, the damping coefficients for a single and double chamber absorbing-type caisson breakwaters are derived based on a single perforated-wall breakwater and a methodology is proposed to enable the estimation of damping coefficient for a breakwater with two chambers.