• 한국미생물·생명공학회지
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• 제23권5호
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• pp.556-558
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• 1995

A strain which showed cephalosporin C resistance and 7-aminocephalosporanic acid sensitivity was isolated from nature. Among the isolates, SS5 was sensitive to cephalosporin C, penicillin G, ampicillin, 7-aminocephalosporanic acid, 6-aminopenicillanic acid, and 7-aminodeacetoxy cephatosporanic acid at concentrations of 1,000 $\mu $g/ml, 2,000 $\mu $g/ml, 3,000 $\mu $g/ml, 30 $\mu $g/ml 100 $\mu $g/ml and 100 $\mu $g/ml, respectively. But SS5 was sensitive at very low concentration of chloramphenicol, kanamycin, neomycin, streptomycin and tetracycline. Since SS5 was sensitive to 7-ACA (30 $\mu $g/ml) and didn't have $\beta $-lactamase activity on the cephalosporin C, SS5 could be useful as an indicator strain for the production of 7-ACA, which is an important precursor for the synthesis of many semisynthetic cephalosporins.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2537-2541
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• 2010

We chose a fluorescent pentapeptide sensor (-CPGHE) containing a dansyl fluorophore as a model peptide and investigated whether the selectivity and sensitivity of the peptides for heavy and transition metal ions could be tuned by changing amino acid sequence. In this process, we developed a selective peptide sensor, Cp1-d (-HHPGE, $K_d\;=\;670\;nM$) for detection of $Zn^{2+}$ in 100% aqueous solution and a selective and sensitive peptide sensor, Cp1-e (-CCHPGE, $K_d\;=\;24\;nM$) for detection of $Cd^{2+}$ in 100% aqueous solution. Overall results indicate that the selectivity and sensitivity of the metallopeptide sensors to specific heavy and transition metal ions can be tuned by changing amino acid sequence.

• 대한임상검사과학회지
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• 제53권4호
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• pp.342-352
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• 2021

제7기 국민건강영양조사 자료(2016~2018)를 이용해서 고감도 C반응성 단백(hsCRP)과 요산의 비만에 대한 위험도와 상호 작용이 있는지 알아보고자 하였다. 비만은 체질량지수(BMI)가 25 kg/m² 이상으로, 중증 비만은 BMI가 30 kg/m² 이상으로, 병적 비만은 BMI가 35 kg/m² 이상으로 정의하였다. 복합표본 다중 로지스틱 회귀분석에서 주요한 위험인자를 추가하여 보정하였음에도 불구하고 고농도의 hsCRP와 고농도의 요산이 동시에 존재하는 그룹은 기준 그룹보다 비만의 오즈비(odds ratio, OR)가 모든 단계에서 높았다(비만, OR 1.89, P<0.001 vs. 심한 비만, OR 5.04, P<0.001 vs. 병적인 비만, OR 8.20, P<0.001). 비만의 단계가 높아질수록 비만에 대한 hsCRP와 요산의 오즈비가 1.89에서 8.20으로 높아졌다, 이는 BMI가 증가된 참가자일수록 hsCRP와 요산의 관련성이 크다는 것을 암시한다. 더욱이, 복합표본 일반선형분석에서 주요한 교란 요인을 보정한 후 비만에 대한 hsCRP와 요산 사이의 상호 작용이 분석되었다(P for interaction=0.009).

• Clinical Nutrition Research
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• 제13권2호
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• pp.121-129
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• 2024

The prevalence of metabolic syndrome caused by diets containing excessive fatty acids is increasing worldwide. Patients with metabolic syndrome exhibit abnormal lipid profiles, chronic inflammation, increased levels of saturated fatty acids, impaired insulin sensitivity, excessive fat accumulation, and neuropathological issues such as memory deficits. In particular, palmitic acid (PA) in saturated fatty acids aggravates inflammation, insulin resistance, impaired glucose tolerance, and synaptic failure. Recently, adiponectin, brain-derived neurotrophic factor (BDNF), and glucose-like peptide-1 (GLP-1) have been investigated to find therapeutic solutions for metabolic syndrome, with findings suggesting that they are involved in insulin sensitivity, enhanced lipid profiles, increased neuronal survival, and improved synaptic plasticity. We investigated the effects of adiponectin, BDNF, and GLP-1 on neurite outgrowth, length, and complexity in PA-treated primary cortical neurons using Sholl analysis. Our findings demonstrate the therapeutic potential of adiponectin, BDNF, and GLP-1 in enhancing synaptic plasticity within brains affected by metabolic imbalance. We underscore the need for additional research into the mechanisms by which adiponectin, BDNF, and GLP-1 influence neural complexity in brains with metabolic imbalances.

• Animal cells and systems
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• 제7권4호
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• pp.345-348
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• 2003

The effects of acute acid stress on hatching success and hatching period of laboratory-reared hermaphroditic fish Rivulus marmoratus were examined. The effects of acute acid toxicity on mortality was also determined in three life stages of this fish. There was a significant negative effect of acid stress on hatching performance in the R. marmoratus embryos. The hatching success was only 5% at pH 3.5 compared to over 78% at pH higher than 4.0. The hatching period was also delayed by low pH treatments. The larval and juvenile stages were more sensitive to acid toxicity on mortality than the adult stage, but larvae and juveniles showed similar sensitivity. The 96-h LC50 value was pH 3.8 in larval and juvenile stages and pH 3.3 in adult stage.

• 한국환경농학회지
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• 제4권2호
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• pp.114-117
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• 1985

식물체내(植物體內) ABA의 미량분석법(微量分析法) 개발(開發)을 위(爲)하여 시험(試驗)한 결과(結果) 식물체(植物體)의 ABA 추출물(抽出物)을 pentafluorobenzyl bromide로 ester 화(化)시켜 ABA-PFB ester 형태(形態)로 GLC-ECD 분석(分析)하므로서 ABA-methyl ester 보다 높은 감도(感度)를 보여 5 pg의 ABA 까지 측정(測定)이 가능(可能)하였다.

• Journal of Photoscience
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• 제7권2호
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• pp.39-44
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• 2000

To examine the chilling tolerance lipids, we compared the chilling susceptibility of photosystem II of wild type tobacco plants with that of transgenic tobacco plants, in which the sensitivity to chilling had been enhanced by genetic modification of fatty acid unsaturation of chloroplast membrane lipids. The transgenic tobacco plants were found to contain reduced levels of unsaturated membrane fatty acids by being tansformed with cDNA for glycerol-3-phosphate acyltransferase from squash. For the purpose of studying on the functional integrity of photosystem II during low-temperature photoinhibition, the photochemical efficiency was measured as the ration of the maximun fluorescence of chlorophyll (Fv/Fm) of photosystem II. In parallel with an investigation on the transgenic plants, susceptibility of chilling-resistant species, such as spinah and pea, and of chilling-sensitive ones, such as squash and sweet potato, to low-temperature photoinhibition was also compared in terms of room temperature-induced chlorophyll fluorescence from photosystem II. When leaf disks from the two genotypes of tobacco plants were exposed to light at 5$^{\circ}C$, the transgenic plants showed more rapid decline in photochemical activity of photosysytme II than wild-type plants. When they were pretreated with lincomycin, an inhibitor of chloroplast-encoded protein synthesis, the extent of photoinhibition was even more accelerated. More impottantly, they showed a comparable extent of photoinhibition in the presence of lincomycin, making a clear contrast to the discrepancy observed in the discrepancy observed in the absence of lincomycin. Restoration of Fv/Fm during recovery from low-temperature photoinhibition occurred more slowly in the transgenic tobacco plants than the wild-type. These findings are discussed in relation to fatty acid unsaturation of membrane phosphatidylglycerol. It appears that the ability of plants to rapidly regenerate the active photosystem II complex from might explain, in part, why chilling-resistant plants can toleratlow-temperature photoinhibition.

• Journal of Nutrition and Health
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• 제35권7호
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• pp.754-762
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• 2002

This study was performed to investigate the effect of sodium intake on blood pressure and blood parameters. 20 young adult women were fed the diets containing 290.5 mEq (high-Na diet) and 51.3 mEq (low-Na diet) Na for 6 days, respectively. BMI, DBP, and MBP were significantly lower in low-Na diet than those in high-Na diet. 20 subjects were divided into 3 groups according to the salt-sensitivity. In salt-sensitive group, decreases in SBP, DBP, and MBP by low-Na diet were shown. And there were not significant difference in blood pressure of salt-resistant group between high- and low-Na diet. In count-reactive group, MBP in low-Na diet was significantly higher than that in high-Na diet. Hemoglobin, creatinine, uric acid, and haptoglobin levels in serum were significantly higher in low-Na diet than those in high-Na diet. Among groups with different salt-sensitivity, increments of haptoglobin by low-Na diet were shown in salt-sensitive and counter-reactive groups. Actually, low sodium diet affects not only the blood pressure, but other biochemical parameters which in turn affect an individual overall health. Also salt-sensitivity should be considered as an important determinant. Therefore, for the patients who need restricted Na diet, it would be suggested that various biochemical changes and individual salt-sensitivity should be carefully considered along with dietary Na manipulation.

• 한국재료학회지
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• 제3권4호
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• pp.319-326
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• 1993

Hydroxide법으로 ${\alpha}$-주산산(stannic acid)을 만든후, 하고온도를 $500^{\circ}C$~$1100^{\circ}C$로 조정하여 일차입자(Crystallite)크기가 8-54nm인 $SnO_2$ 분말을 제작하였다. 분말의 입자(drystalite)클기에 따른 분말특성와 $H_2$, CO가스(0.5v/o)에 대한 감응성 미치공기중에서의 저상변화특성에 미치는 영향을 조사하였다. 입자크기가 감소함에 따라, 분말의 FTIR 흡습특성은 증가하였으나, 격자상수는 일정하였다. 후막소자에서, $H_2$가스에 대해 최대감도를 나타내는 온도와 공기중에서 최소저항을 나타내는 온도는 입자크기가 미세해짐에 따라 점차 낮아졌다. 최소저항점과 최대감도점의 온도저하를 산소흡착종의 활성화에너지의 감소라고 유추하였고, 이러한 에너지의 감소가 미세입자에 의한 감도향상요인 중의 한가지라고 제의하였다.

• Macromolecular Research
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• 제17권12호
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• pp.1025-1031
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• 2009

Several kinds of biodegradable hydrogels were prepared via in situ photopolymerization of Pluronic F127/poly($\varepsilon$-caprolactone) macromer and acrylic acid (AA) comonomer in aqueous medium. The swelling kinetics measurements showed that the resultant hydrogels exhibited both thermo- and pH-sensitive behaviors, and that this stimuli-responsiveness underwent a fast reversible process. With increasing pH of the local buffer solutions, the pH sensitivity of the hydrogels was increased, while the temperature sensitivity was decreased. In vitro hydrolytic degradation in the buffer solution (pH 7.4, $37^{\circ}C$), the degradation rate of the hydrogels was greatly improved due to the introduction of the AA comonomer. The in vitro release profiles of bovine serum albumin (BSA) in-situ embedded into the hydrogels were also investigated: the release mechanism of BSA based on the Peppas equation was followed Case II diffusion. Such biodegradable dual-sensitive hydrogel materials may have more advantages as a potentially interesting platform for smart drug delivery carriers and tissue engineering scaffolds.