• Macromolecular Research
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• 제10권3호
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• pp.168-173
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• 2002

Unstabilized low-density polyethylene (LDPE) films and films formulated with hindered amine light stabilizer (HALS) were exposed to UV-radiation; and the physicochemical changes during photooxidation processes have been investigated using tensile, FTIR spectre-photometric and thermal analytical (DSC) techniques. The dependence of tensile properties (elongation- and stress-at-break), carboxyl index and heat of fusion on UV-irradiation time have been discussed. The use of HALS is found to be effective in maintaining the UV-mechanical properties of the LDPE films. The experimental results showed that there exists no correlation between mechanical properties and carbonyl index, whereas crystallinity correlates well with carbonyl index in unstabilized and stabilized films for irradiation times greater than 100 h. The rate of formation of carbonyl groups is found to be dependent on UV exposure time. Crystallinity of the film samples is strongly influenced by both exposure time and presence of HALS.

• Bulletin of the Korean Chemical Society
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• 제21권1호
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• pp.49-55
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• 2000

A series of m-, and p-substituted phenyl 2-thiophenecarboxylates and benzoates was prepared by the reaction of the corresponding acyl chlorides and phenols. Their $^1H$ and $^{13}C$ NMR chemical shifts were analyzed using single substituent parameter (S SP) and dual substituent parameter (DSP) methods. The relative aromaticity index of thiophene was estimated to be 0.92 from the plot of the chemical shift of the carbonyl carbons of the thienoyl esters against chemical shift of the carbonyl carbons of the benzoyl esters.

• 공업화학
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• 제24권2호
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• pp.138-143
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• 2013

화학적 열화를 빠르게 유도할 수 있는 단파장의 자외선(254 nm)을 고밀도 폴리에틸렌의 표면에 조사하여, 생성된 carbonyl band의 변화로부터 기계적 물성 변화를 예측할 수 있는 지에 대한 가능성을 연구하였다. 오랜 시간이 요구되는 자연 태양광에 의한 옥외폭로시험이나, 제논-아크 광원에 의한 광 열화 대신에 광양자 에너지가 높은 UVC 램프를 사용함으로써, 유도되는 광열화의 화학적 특성이 동일한 기계적 물성 변화를 유발하는지를 확인하는 것에 본 연구의 의미가 있다. 인장시험과 크리프-파괴시험으로 진행된 고밀도 폴리에틸렌의 기계적 강도는 CI 변화에 유사한 양상을 보였으며, 특히 항복강도와 신장률은 자외선 노출시간과 밀접한 관계가 있음을 보여주었다. 따라서 빠른 표면 열화를 유발하는 UVC 램프를 활용한 카르보닐 지수와 기계적 물성 변화의 관계를 통하여 장시간이 요구되는 옥외에서의 기계적 물성변화를 보다 빠르게 파악할 수 있는 방법을 제시하였다.

• Toxicological Research
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• 제20권3호
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• pp.213-223
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• 2004

This work aimed to study the effectiveness of cellular oxidative parameter (malondial-dehyde, protein carbonyl, and 8-hydroxy-2'deoxyguanosine). The experimental groups were aluminum treated rats and control rats. Aluminum treatd rats were given intraperitoneally aluminum nitrate nonahydrate ($Al^{3+}$, 0.2 mmol/kg) daily for 30 days except Sunday. Control rats were injected 1 ml of saline. After the dose, rats were decapitated and hippocampus and cerebral cortex were removed. The measured parameters were tissue malondialdehyde (MDA, index of lipid peroxidation), protein carbonyl (index of protein oxidation), 8-hydroxy-2'-deoxy-guanosine (8-OHdG, index of DNA oxidation), reduced glutathione (GSH) levels as well as glutathione reductase (GR) and catalase. AI concentrations in the tissues were also measured. All results were corrected by tissue protein levels. The results were as followed; 1. The concentrations of AI in the cortex and hippocampus were significantly higher in the AI-treated rats than in the control rats. 2. Antioxidative enzyme's activity, catalase and GR, were significantly higher in the AI-treated rats than the control rats. GSH levels were also higher in the AI-treated rats. 3. MDA, protein carbonyl, and 8-OHdG concentration of AI-treated rats were significantly higher than those of control rats. 4. The concentrations of antioxidants, and oxidative stress parameter were correlated with the concentrations of AI in hippocampus and cerebral cortex. Catalase and GR activity were also correlated with the concentration of AI. Based on these results, it can be suggested that intraperitoneally injected AI was accumulated in the brain and induced the increase of antioxidant levels and antioxidative enzyme activity. Also, the oxidative products of cellular macromolecules are significantly related to tissue AI concentration. Therefore MDA, protein carbonyl, and 8-OHdG are useful markers for oxidative stress on cellular macromolecules.

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2494-2498
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• 2012

Preparation of several new spirocyclic mercapto derivatives is described. Thiol protection on multi-carbonyl compounds allows of high sulfur content necessary to induce high refractive index. Condensation of 1,3-dimercapto-2-propanol and cyclohexanone followed by successive oxidation and thioacetalization affords a dispirocycle with four sulfurs. Selective S,S-protection of cyclohexane-1,4-dione is achieved with 1,3-dimercapto-2-propanol and 2,3-dimercapto-1-propanol to provide dispirocycles with four sulfurs. Olefine-oxidation of norbornene gives a useful dialdehyde intermediate which is transformed to 1,3-dithiolane for a linearly-bound-cyclic molecule. Refractive index of linearly-bound-cycles was below 1.60 and dispirocycles exhibited high refractive index of 1.57-1.69.

• 한국수산과학회지
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• 제42권2호
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• pp.104-108
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• 2009

Glycation and oxidation induce formation of carbonyl (CO) groups in proteins, which can be used to develop an index of cellular aging. Methyl glyoxal (MG) and hypochlorite anions are deleterious products of oxygen free-radical reaction. The effects of eel carnosine on protein modification mediated by MG and hypochlorite were studied. MG and hypochlorite induced formation of carbonyl groups with high molecular weight and cross-linked forms of ovalbumin. The presence of eel carnosine effectively inhibited these modifications in a concentration-dependent manner. Imidazole ring in eel carnosine might have a primary role in inhibition of protein glycation. Our data suggests that the eel carnosine may be useful as a "natural" anti-glycating agents.

• 한국연초학회지
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• 제17권2호
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• pp.139-148
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• 1995

This study was carried out to investigate the effects of super heated steam on the physical and chemical changes of burley cut tobacco. Total sugar, total alkaloid, ether extracts, crude ash, total nitrogen and pH for leaf chemical constituents were analyzed. Filling power and fineness index for physical properties, and carbonyl compounds, phenol compounds, amonia, pH, hydrogen cyanide nicotine, carbon monoxide, total volatile base and tar for smoke components were also analyzed. The cut tobacco treated with super heated steam showed significant decrease in total sugar and total alkaloid. The filling power of the sample treated with the super heated steam system was increased abruptly when heated at over 250℃. The fineness index showed similar tendency to that of common toast method. Super heated steam treatment slightly decreased carbonyl compounds, phenol compounds, hydrogen cyanide, nicotine, carbon monoxide and tar in the tobacco. Especially the decrease of ammonia was the most remarkable. The pH of smoke was a little different compared with that in the common toast. The sensory test results showed that, compared to the common conveyer moving system, the tobacco treated with super heated steam system brought out more roasted flavor, lowered impact, irritation, and sting, further improved aftertaste, and lowered bitterness. The super heated steam treatment method used in the studies is expected to give better filling power, mild taste and toasted odor of tobacco than that of the common method for toast treatment. Key words : burley tobacco, super heated steam, expansion, toast.

• 동아시아식생활학회지
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• 제16권4호
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• pp.399-407
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• 2006

We evaluated the effects of butterbur (Petasites japonicus Maxim) addition to the diet on lipid profiles and antioxidant biomarkers such as total glutathionine, TBARS value, carbonyl value, GPx, GR, SOD and paraoxonase activity in the plasma or liver of mice. The distribution of body fat deposition, total cholesterol (TC) contents, and atherogenic index in the plasma were significantly decreased in the butterbur group. The levels of GSH and the activity of GR and SOD were significantly higher in the liver of the butterbur group than in that of the control group. Lipid oxidation of the liver and kidney and protein oxidation of the liver and heart were decreased in the butterbur group. Additionally, the DNA damage, as determined using the comet assay (single cell gel assay) with alkaline electrophoresis and as quantified by measuring the tail length (TL), was decreased in the butterbur group. The results of the present study showed that a diet with added butterbur exerts degenerative disease-protective effects on oxidative DNA damage and lipid peroxidation.

• Tuberculosis and Respiratory Diseases
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• 제61권4호
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• pp.330-338
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• 2006

연구배경: 만성폐쇄성폐질환은 기도염증으로 인한 기도폐쇄를 특징으로 하는 질환이지만, 질병의 경과중에 체중감소나 근위축 같은 전신증상을 동반하게 된다. 만성 염증과 산화 스트레스가 만성폐쇄성폐질환의 병인에 중요한 역할을 하므로 신체질량지수의 감소와 관련이 있을 것으로 추측할 수 있다. 연구자 등은 안정된 만성폐쇄성폐질환 환자에서 신체질량지수와 관련된 인자를 알아보기 위해 다음과 같은 연구를 시행하였다. 방 법: 안정된 만성폐쇄성폐질환 환자 53명(남:여=49:4, 평균나이=$68.25{\pm}6.32$)과 정상 대조군 33명을 대상으로 폐기능 검사를 실시하고 전신염증인자로 혈청 IL-6, TNF-$\alpha$를 측정하고 산화 스트레스 인자로 혈청 8-iso-prostaglandin $F_2{\alpha}$와 carbonyl protein을 측정하여 비교하였다. 또한 만성폐쇄성폐질환 환자를 신체질량지수에 따라 다시 3군(<18.5, 18.5-25, >25)으로 나누어 각각의 수치들을 비교하였고 만성폐쇄성폐질환의 중증도에 따라 신체질량지수를 비교하였다. 결 과: 만성폐쇄성폐질환 환자와 정상 대조군의 혈청에서 IL-6, TNF-$\alpha$, carbonyl protein은 유의한 차이가 없었으며 8-iso-prostaglandin $F_2{\alpha}$은 각각 $456.08{\pm}574.12pg/ml$, $264.74{\pm}143.15pg/ml$로 만성폐쇄성폐질환 환자에서 유의하게 높았다(p<0.05). 만성폐쇄성폐질환에서 신체질량지수의 차이에 따라 혈청 IL-6, TNF-$\alpha$, carbonyl protein과 8-iso-prostaglandin $F_2{\alpha}$은 유의한 차이를 보이지 않았다. 신체질량지수에 따른 환자의 $FEV_1$은 각각 $0.93{\pm}0.25L$, $1.34{\pm}0.52L$, $1.72{\pm}0.41L$로 신체질량지수가 낮을수록 $FEV_1$ 값도 감소하는 경향을 보였고(p=0.002, r=0.42), 최중증 만성폐쇄성폐질환 환자의 신체질량지수는 $19.8{\pm}2.57$로 중등증의 환자의 $22.6{\pm}3.14$에 비해 유의하게 낮았다(p<0.05). 결 론: 본 연구에서 안정된 만성폐쇄성폐질환 환자의 신체질량지수는 전신염증인자와 산화 스트레스의 정도와는 관련을 보이지 않았으나 기도폐쇄의 정도와는 관련이 있을 것으로 사료된다. 만성폐쇄성폐질환 환자에서 신체질량지수의 감소와 관련된 인자에 대해서는 추가적인 연구가 필요할 것으로 사료된다.

• Nutrition Research and Practice
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• 제7권6호
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• pp.430-438
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• 2013

Increased oxidative stress in obese diabetes may have causal effects on diabetic complications, including dyslipidemia. Lipopolysccharides (LPS) along with an atherogenic diet have been found to increase oxidative stress and insulin resistance. Cranberry has been recognized as having beneficial effects on diseases related to oxidative stress. Therefore, we employed obese diabetic animals treated with an atherogenic diet and LPS, with the aim of examining the effects of cranberry powder (CP) on diabetic related metabolic conditions, including lipid profiles, serum insulin and glucose, and biomarkers of oxidative stress. Forty C57BL/KsJ-db/db mice were divided into the following five groups: normal diet + saline, atherogenic diet + saline, atherogenic diet + LPS, atherogenic diet + 5% CP + LPS, and atherogenic diet + 10% CP + LPS. Consumption of an atherogenic diet resulted in elevation of serum total cholesterol and atherogenic index (AI) and reduction of high density lipoprotein (HDL)-cholesterol. However, with 10% CP, the increase in mean HDL-cholesterol level was close to that of the group with a normal diet, whereas AI was maintained at a higher level than that of the group with a normal diet. LPS induced elevated serum insulin level was lowered by greater than 60% with CP (P < 0.05), and mean serum glucose level was reduced by approximately 19% with 5% CP (P > 0.05). Mean activity of liver cytosolic glutathione peroxidase was significantly increased by LPS injection, however it was reduced back to the value without LPS when the diet was fortified with 10% CP (P < 0.05). In groups with CP, a reduction in mean levels of serum protein carbonyl tended to occur in a dose dependent manner. Particularly with 10% CP, a reduction of approximately 89% was observed (P > 0.05). Overall results suggest that fortification of the atherogenic diet with CP may have potential health benefits for obese diabetes with high oxidative stress, by modulation of physical conditions, including some biomarkers of oxidative stress.