• 한국잡초학회지
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• 제30권1호
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• pp.43-49
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• 2010

본 시험은 2008년에 경상북도 농업기술원 벼 재배포장에서 최근 담수직파답에서 제초제 저항성 잡초로 가장 문제시 되고 있는 잡초 중 올챙이고랭이를 대상으로 잡초 밀도별 벼와의 경합력을 구명하고 Rectangular hyperbola 모델을 기초로 잡초의 밀도에 따른 쌀 수량 감소를 예측하여 경제적인 방제 필요수준을 구명하고자 실시하였다. 잡초를 완전 방제 했을 경우를 가상한 벼 수량은 올챙이고랭이에서 10a당 466kg으로 피의 457kg보다 다소 높았으며, 벼와 잡초의 경합력은 올챙이고랭이에서 0.00188로 피의 0.02402 보다 낮았고, 수량 예측식은 올챙이고랭이가 y = 466/(1+0.00188x), $R^2$ = 0.933, 피가 y = 458/(1+0.02402x), $R^2$ = 0.973로 나타났다. 제초제 구입 비용을 10a당 12,492원, 제초제 살포 인건비를 9,936원, 쌀의 가격을 kg당 2,000원, 제초제 방제가 95%로 적용하여 구한 경제적 피해 한계 밀도는 잡초 완전 방제시 수량이 10a당 466kg이고 잡초 1본당 수량 감수정도가 0.001884인 올챙이고랭이는 평방미터당 13.4본, 잡초 완전 방제시 수량이 458kg이고 잡초 1본당 수량 감수 정도가 0.02402인 피는 평방미터당 1.07본이었다.

• 한국환경보건학회지
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• 제37권6호
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• pp.450-459
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• 2011

Objectives: Biomarkers in urine are important in assessing exposures to environmental or occupational chemicals and for evaluateing renal function by exposure from these chemicals. Spot urine samples are needed to adjust the concentration of these biomarkers for variations in urine dilution. This study was conducted to evaluate the suitability of adjusting the urinary concentration of cadmium (uCd) and arsenic (uAs) by specific gravity (SG) and urine creatinine (uCr). Methods: We measured the concentrations of blood cadmium (bCd), uCd, uAs, uCr, SG and N-acetyl-${\beta}$-D-glucosaminidase (NAG) activity, which is a sensitive marker of tubular damage by low dose Cd exposure, in spot urine samples collected from 536 individuals. The value of uCd, uAs and NAG were adjusted by SG and uCr. Results: The uCr levels were affected by gender (p < 0.01) and muscle mass (p < 0.01), while SG levels were affected by gender (p < 0.05). Unadjusted uCd and uAs were correlated with SG (uCd: r = 0.365, p < 0.01; uAs: r = 0.488, p < 0.01), uCr (uCd: r = 0.399, p < 0.01; uAs: r = 0.484, p < 0.01). uCd and uAs adjusted by SG were still correlated with SG (uCd: r = 0.360, p < 0.01, uAs: r = 0.483, p < 0.01). uCd and uAs adjusted by uCr and modified uCr ($M_{Cr}$) led to a significant negative correlation with uCr (uCd: r = -0.367, p < 0.01; uAs: r = -0.319, p < 0.01) and $M_{Cr}$ (uCd: r = -0.292, p < 0.01; uAs: r = -0.206, p < 0.01). However, uCd and uAs adjusted by conventional SG ($C_{SG}$) were disappeared from these urinary dilution effects (uCd: r = -0.081; uAs: r = 0.077). Conclusions: $C_{SG}$ adjustment appears to be more appropriate for variations in cadmium and arsenic in spot urine.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1359-1366
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• 2000

An experiment was carried out to study plasma levels of hormones and metabolites of crossbred Holstein cattle during late pregnancy (28 days pre partum), early lactation (30 days post partum), mid-lactation (120 days post partum) and late lactation (210 days post partum). Two breed types of Holstein $Friesian{\times}Red$ Sindhi (50:50 = 50%HF) and Holstein $Friesian{\times}Red$ Sindhi (87.5:12.5 = 87.5%HF) were divided into four groups of four animals each. Two groups of each breed were fed with either rice straw treated with 5% urea or pangola hay (Digitaria decumbens) as the source of roughage throughout the experiments. There were a substantial increases in the mean levels of total triiodothyronine ($T_3$), insulin and glucagon at the onset of lactation, and maintained in a high levels during lactation advance for all groups of experiments. The mean levels of prolactin and thyroxine ($T_4$) were not significantly different among groups of animals, but the plasma cortisol concentration was slightly higher in both groups of 50%HF in comparison with those of 87.5%HF animals. The mean levels of plasma growth hormone (GH) of both groups of 87.5%HF animals feeding on either hay or urea treated rice straw markedly rose in the early period of lactation and markedly reduced in mid- and late lactation. These changes were accompanied with changes of milk yield. In contrast to 50%HF animals, plasma GH levels were considerably higher in the late pregnant period than in the early period of lactation and it remained constant as its value at the early lactation throughout the experimental period. The high levels of both plasma progesterone and estradiol concentration significantly declined after parturition and remained low through lactating period. The plasma glucose level in the 50%HF animals feeding on either hay or urea treated rice straw was higher than the 87.5%HF animals in all periods of experiments. Changes in plasma FFA levels of both types of crossbred animals were depended on the endocrine status during late pregnancy and lactation. The levels of plasma FFA of 50%HF animals were significantly higher (p<0.05) than those of 87.5%HF animals during late pregnancy. Both plasma ${\beta}$-hydroxybutyrate and lactate concentrations were not affected by feeding on either hay or urea treated rice straw during late pregnancy and lactation. These data demonstrate that there were no differences in the physiological performances in the same crossbred animals fed either hay or urea treated rice straw. The 87.5%HF animal has the genetic potential for a high milk yield and homeorhetic adaptation for mammary function differed from 50%HF animals during periods of lactation. Altering lactation persistency in 87.5%HF is regulated mainly by chronically acting growth hormones through the period of lactation.

• The Korean Journal of Physiology and Pharmacology
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• 제9권2호
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• pp.103-108
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• 2005

To study the direct effect of somatostatin (SS) on calcium channel current ($I_{Ba}$) in guinea-pig gastric myocytes, $I_{Ba}$ was recorded by using whole-cell patch clamp technique in single smooth muscle cells. Nicardipine ($1{\mu}M$), a L-type $Ca^{2+}$ channel blocker, inhibited $I_{Ba}$ by $98{\pm}1.9$% (n=5), however $I_{Ba}$ was decreased in a reversible manner by application of SS. The peak $I_{Ba}$ at 0 mV were decreased to $95{\pm}1.5$, $92{\pm}1.9$, $82{\pm}4.0$, $66{\pm}5.8$, $10{\pm}2.9$% at $10^{-10}$, $10^{-9}$, $10^{-8}$, $10^{-7}$, $10^{-5}$ M of SS, respectively (n=3∼6; $mean{\pm}SEM$). The steady-state activation and inactivation curves of $I_{Ba}$ as a function of membrane potentials were well fitted by a Boltzmann equation. Voltage of half-activation ($V_{0.5}$) was $-12{\pm}0.5$ mV in control and $-11{\pm}1.9$ mV in SS treated groups (respectively, n=5). The same values of half-inactivation were $-35{\pm}1.4$ mV and $-35{\pm}1.9$ mV (respectively, n=5). There was no significant difference in activation and inactivation kinetics of $I_{Ba}$ by SS. Inhibitory effect of SS on $I_{Ba}$ was significantly reduced by either dialysis of intracellular solution with $GDP_{\beta}S$, a non-hydrolysable G protein inhibitor, or pretreatment with pertussis toxin (PTX). SS also decreased contraction of guinea-pig gastric antral smooth muscle. In conclusion, SS decreases voltage-dependent L-type calcium channel current ($VDCC_L$) via PTXsensitive signaling pathways in guinea-pig antral circular myocytes.

• The Korean Journal of Physiology and Pharmacology
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• 제22권6호
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• pp.661-670
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• 2018

Fimasartan, a new angiotensin II receptor antagonist, reduces myocyte damage and stabilizes atherosclerotic plaque through its anti-inflammatory effect in animal studies. We investigated the protective effects of pretreatment with fimasartan on ischemia-reperfusion injury (IRI) in a mouse model of ischemic renal damage. C57BL/6 mice were pretreated with or without 5 (IR-F5) or 10 (IR-F10) mg/kg/day fimasartan for 3 days. Renal ischemia was induced by clamping bilateral renal vascular pedicles for 30 min. Histology, pro-inflammatory cytokines, and apoptosis assays were evaluated 24 h after IRI. Compared to the untreated group, blood urea nitrogen and serum creatinine levels were significantly lower in the IR-F10 group. IR-F10 kidneys showed less tubular necrosis and interstitial fibrosis than untreated kidneys. The expression of F4/80, a macrophage infiltration marker, and tumor necrosis factor $(TNF)-{\alpha}$, decreased in the IR-F10 group. High-dose fimasartan treatment attenuated the upregulation of $TNF-{\alpha}$, interleukin $(IL)-1{\beta}$, and IL-6 in ischemic kidneys. Fewer TUNEL positive cells were observed in IR-F10 compared to control mice. Fimasartan caused a significant decrease in caspase-3 activity and the level of Bax, and increased the Bcl-2 level. Fimasartan preserved renal function and tubular architecture from IRI in a mouse ischemic renal injury model. Fimasartan also attenuated upregulation of inflammatory cytokines and decreased apoptosis of renal tubular cells. Our results suggest that fimasartan inhibited the process of tubular injury by preventing apoptosis induced by the inflammatory pathway.

• 한국산학기술학회논문지
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• 제18권8호
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• pp.285-293
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• 2017

본 연구의 목적은 다면적 인성검사(MMPI-2)의 임상척도와 뇌기능지수 중 자기조절지수와의 관련성을 알아보고자 하는데 있다. 연구는 상담센터에 내원한 20세 이상의 성인 남녀 중 자원한 41명을 대상으로 진행하였다. 자기보고식 검사지인 다면적 인성검사(MMPI-2)를 이용해 검사를 진행했으며, 2채널 뇌파측정기를 이용해 Fp1,과 Fp2에서 뇌파를 측정하였다. 연구결과는 다면적 인성검사(MMPI-2)의 임상척도인 척도2(D)와 자기조절지수 중 휴식 즉, 알파파와 음의 상관을 보였으며, 다면적 인성검사(MMPI-2) 척도3(Hy)은 집중력 즉, 저베타파와 양의 상관성을 보였고, 척도 7(Pt)은 휴식과 음의 상관성을 보였다. 상담현장에서 다면적 인성검사(MMPI-2)와 SQR을 상호 보완하여 사용할 수 있다는데 본 연구의 의의가 있다. 이러한 결과는 세 가지 시사점을 갖는 것으로 해석 가능하다. 첫째, 우울한 정서를 가진 사람들은 타인의 시선과 평가에 민감하여 대인관계를 맺을 시 많은 에너지를 사용하게 되어 휴식이 유지되지 못하기 때문에 피로도가 상승할 수 있다. 둘째, 지나치게 타인의 관심을 얻으려고 하고 쾌활한 모습을 지닌 사람들은 활동력이 높을 것으로 여겨진다. 셋째, 불안과 긴장 상태로 스트레스가 높아진 사람들은 쉽게 지치고 짜증과 불쾌감이 상승할 수 있다는 것을 시사한다.

• The Korean Journal of Physiology and Pharmacology
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• 제18권3호
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• pp.255-261
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• 2014

Essential fatty acid (EFA) is known to be required for the body to function normally and healthily. However, the effect of EFA on glucose uptake in skeletal muscle has not yet been fully investigated. In this study, we examined the effect of two EFAs, linoleic acid (LA) and ${\alpha}$-linolenic acid (ALA), on glucose uptake of C2C12 skeletal muscle cells and investigated the mechanism underlying the stimulatory effect of polyunsaturated EFAs in comparison with monounsaturated oleic acid (OA). In palmitic acid (PA)-induced insulin resistant cells, the co-treatment of EFAs and OA with PA almost restored the PA-induced decrease in the basal and insulin-stimulated 2-NBDG (fluorescent D-glucose analogue) uptake, respectively. Two EFAs and OA significantly protected PA-induced suppression of insulin signaling, respectively, which was confirmed by the increased levels of Akt phosphorylation and serine/threonine kinases ($PKC{\theta}$ and JNK) dephosphorylation in the western blot analysis. In PA-untreated, control cells, the treatment of $500{\mu}M$ EFA significantly stimulated 2-NBDG uptake, whereas OA did not. Phosphorylation of AMP-activated protein kinase (AMPK) and one of its downstream molecules, acetyl-CoA carboxylase (ACC) was markedly induced by EFA, but not OA. In addition, EFA-stimulated 2-NBDG uptake was significantly inhibited by the pre-treatment of a specific AMPK inhibitor, adenine 9-${\beta}$-D-arabinofuranoside (araA). These data suggest that the restoration of suppressed insulin signaling at PA-induced insulin resistant condition and AMPK activation are involved at least in the stimulatory effect of EFA on glucose uptake in C2C12 skeletal muscle cells.

• Nutrition Research and Practice
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• 제1권2호
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• pp.105-112
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• 2007

Ascorbic acid has been reported to extend replicative life span of human embryonic fibroblast (HEF). Since the detailed molecular mechanism of this phenomenon has not been investigated, we attempted to elucidate. Continuous treatment of HEF cells with ascorbic acid at ($200{\mu}M$) from 40 population doubling (PD) increased maximum PD numbers by 18% and lowered $SA-{\beta}-gal$ positive staining, an aging marker, by 2.3 folds, indicating that ascorbic acid extends replicative life span of HEF cells. Ascorbic acid treatment lowered DCFH by about 7 folds and Rho123 by about 70%, suggesting that ascorbic acid dramatically decreased ROS formation. Ascorbic acid also increased aconitase activity, a marker of mitochondrial aging, by 41%, indicating that ascorbic acid treatment restores age-related decline of mitochondrial function. Cell cycle analysis by flow cytometry revealed that ascorbic acid treatment decreased G1 population up to 12%. Further western blot analysis showed that ascorbic acid treatment decreased levels of p53, phospho-p53 at ser 15, and p21, indicating that ascorbic acid relieved senescence-related G1 arrest. Analysis of AP (apurinic/apyrimidinic) sites showed that ascorbic acid treatment decreased AP site formation by 35%. We also tested the effect of hydrogen peroxide treatment, as an additional oxidative stress. Continuous treatment of $20{\mu}M$ of hydrogen peroxide from PD 40 of HEF cells resulted in premature senescence due to increased ROS level, and increased AP sites. Taken together, the results suggest that ascorbic acid extends replicative life span of HEF cells by reducing mitochondrial and DNA damages through lowering cellular ROS.

• 농약과학회지
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• 제9권2호
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• pp.140-145
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• 2005

정량적 구조 활성관계 모델링은 물리적인 성질과 생물학적 활성이 관계 있다는 것을 전제로 한다. 그러나, 퍼센트 활성과 같은 데이터들은 모델링에 많이 활용되지 않았다. 이것의 중요한 이유중의 하나는 이러한 값들이 정량적이 아니고 정성적인 데에 있다. 본 연구에서는 분자모델링에 퍼센트활성 데이터를 활용하기 위하여 데이터 값들을 2개의 계층으로 분류하고 CoMFA(비교분자장)를 판별함수로 활용하였다. 즉, 베타-케토아세트아닐라이드 유도체들의 토마토 역병균에 대한 항균력 시험의 퍼센트 활성 데이터를, 한 계층은 활성이 있는 것, 다른 계층은 활성이 없는 것으로 나누었다. 특히, CoMFA를 활용함으로써 화학적인 이해에 중요한 3차원적인 정보를 얻을 수 있었다. 이 모델은 주어진 데이타를 98%의 정확도로 설명하였으며, LOO 검증을 해본 결과 예측력은 약 69% 정도였다 이 결과는 활성 데이터를 근사적으로 2개의 계급으로 나누고 CoMFA를 활용하는 방식이 구조활성관계를 이해하고 화합물 유도체를 합성하는데 활용될 수 있음을 보여준다.

• IMMUNE NETWORK
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• 제3권3호
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• pp.201-210
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• 2003

Objective: The role of prostaglandin $E_2$ (PGE2) in the etiopathogenesis of immune and inflammatory diseases has become the subject of recent debate. To determine the role of PGE2 in rheumatoid arthritis (RA), we tested the effect of exogenous PGE2 on the production of cyclooxygenase-2 (COX-2) by rheumatoid synoviocytes. Methods: Fibroblast-like synoviocytes (FLS) were prepared from the synovial tissues of RA patients, and cultured in the presence of PGE2. The COX-2 mRNA and protein expression levels were determined by RT-PCR and Western blot analysis, respectively. The PGE2 receptor subtypes in the FLS were analyzed by RT-PCR. Electrophoretic mobility shift assay (EMSA) was used to measure the NF-${\kappa}B$ binding activity for COX-2 transcription. The in vivoeffect of PGE2 on the development of arthritis was also tested in collagen induced arthritis (CIA) animals. Results: PGE2 ($10^{-11}$ to $10^{-5}M$) dose-dependently inhibited the expression of COX-2 mRNA and the COX-2 protein stimulated with IL-$1{\beta}$, but not COX-1 mRNA. NS-398, a selective COX-2 inhibitor, displayed an additive effect on PGE2-induced COX-2 downregulation. The FLS predominantly expressed the PGE2 receptor (EP) 2 and EP4, which mediated the COX-2 suppression by PGE2. Treatment with anti-IL-10 monoclonal antibodies partially reversed the PGE2-induced suppression of COX-2 mRNA, suggesting that IL-10 may be involved in modulating COX-2 by PGE2. Experiments using an inducer and an inhibitor of cyclic AMP (cAMP) suggest that cAMP is the major intracellular signal that mediates the regulatory effect of PGE2 on COX-2 expression. EMSA revealed that PGE2 inhibited the binding of NF-${\kappa}B$ in the COX-2 promoter via a cAMP dependent pathway. In addition, a subcutaneous injection of PGE2 twice daily for 2 weeks significantly reduced the incidence and severity of CIA as well as the production of IgG antibodies to type II collagen. Conclusion: Our data suggest that overproduced PGE2 in the RA joints may function as an autocrine regulator of its own synthesis by inhibiting COX-2 production and may, in part, play an anti-inflammatory role in the arthritic joints.