• BMB Reports
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• 제35권1호
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• pp.127-133
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• 2002

Nitrosative stress can prevent or induce apoptosis. It occurs via S-nitrosylation by the interaction of nitric oxide (NO) with the biological thiols of proteins. Cellular redox potential and non-heme iron content determine S-nitrosylation. Apoptotic cell death is inhibited by S-nitrosylation of the redox-sensitive thiol in the catalytic site of caspase family proteases, which play an essential role in the apoptotic signal cascade. Nitrosative stress can also promote apoptosis by the activation of mitochondrial apoptotic pathways, such as the release of cytochrome c, an apoptosis-inducing factor, and endonuclease G from mitochondria, as well as the suppression of NF-${\kappa}B$ activity. In this article we reviewed the mechanisms whereby S-nitrosylation and nitrosative stress regulate the apoptotic signal cascade.

• Clinical and Experimental Pediatrics
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• 제49권11호
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• pp.1223-1226
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• 2006

철적모구성 빈혈은 heme 대사의 이상으로 혈청철의 증가와 소구성 저색소성 빈혈을 보이며, 골수 소견에서 적혈구계 과다형성과 함께 환상 철적모구가 많이 나타나는 것이 특징이다. 저자들은 2세 남아에서 드문 질환인 철적모구성 빈혈과 승모판 탈출증에 의한 승모판 역류가 동시에 있는 증례를 경험하였다. 환아는 철적모구성 빈혈에 의해 수혈에 따른 철분의 과잉 침착과 만성 빈혈에 의한 심계 항진에 의한 심근 기능 장애가 발생할 가능성이 있는데다, 동반된 승모판 탈출증으로 심기능의 장애의 위험이 증가할 것으로 사료된다. 현재 환아는 pyridoxine 투약 후 전신 상태와 혈색소 수치가 안정적으로 유지되고 있다.

• 한국식생활문화학회지
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• 제37권2호
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• pp.171-177
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• 2022

This study evaluated the nutritional composition and quality traits of rabbit meat as compared to chicken meat. Samples of loin (M. longissimus dorsi) and breast meats were collected from rabbit and chicken carcasses, respectively. The meats were then analyzed for the proximate composition, collagen and energy contents, fatty acid composition, myoglobin and heme iron contents, pH value, water-holding capacity (WHC), cooking loss, meat color, Warner-Bratzler shear force (WBSF) value, and texture profile. Compared to chicken breast meat, lower (p<0.05) protein content and higher (p<0.05) ash and collagen contents were obtained in rabbit loin meat. Rabbit meat remarkably had higher (p<0.05) total polyunsaturated fatty acids (PUFA) and linolenic acid contents and lower (p<0.05) n-6/n-3 PUFA ratio as compared to chicken meat. The pH value and WHC were lower (p<0.05) in rabbit meat than in chicken meat (p<0.05). Rabbit meat exhibited lower (p<0.05) L^* value and higher (p<0.05) a^* and b^* values compared to chicken meat (p<0.05). The WBSF value, hardness, and gumminess were higher (p<0.05) in rabbit meat than in chicken meat (p<0.05). These findings suggest that rabbit meat has higher essential n-3 PUFA, darker color, and firmer texture as compared to chicken meat.

• Nutritional Sciences
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• 제7권2호
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• pp.113-120
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• 2004

This study was conducted to investigate variables related to dietary fiber intake among sixth grade children in an elementary school in Daejon city. One hundred and forty-seven children completed a questionnaire for determining their socioeconomic background and their food habits. Anthropometric measurements were taken, and a 24-hour diet recall method was used to collect three-day food intakes. The socioeconomic status of the children's families belonged to the upper middle class; 53.0% of their fathers and 25.8% of their mothers had completed college or higher degrees. 27.9% of the mothers had jobs, including part-time jobs. Approximately 30% of the children skipped breakfast, 66.4% of the children preferred animal foods to plant foods, and 52.4% of the children preferred green vegetables to yellow or pale vegetables. Grilled meat dishes, such as Grilled beef rib with seasoning, Bulgogi, grilled pork belly and beef steaks, were the most popular types of food eaten outside home by the children. Daily dietary fiber intake was 14.5 g in boys and 14.5 g in girls, and these intakes are low compared to the standard guidelines. The average intakes of energy and protein of the children were 84.5% and 114.0% of the Korean Recommended Dietary Allowances (RDAs), respectively. Besides energy, riboflavin, iron and calcium intakes were below the RDAs, and especially calcium intake was only 50% of the RDAs. On the other hand, thiamin, niacin, ascorbic acid, protein and phosphorus intakes exceeded the Korean RDAs. Family income or the children's body mass index (BMI) was not directly related to dietary fiber intakes. However, higher dietary fiber intakes tended to be related to higher intakes of green vegetables and fruits. Children with higher dietary fiber intake tended to prefer plant foods to animal foods. Energy and most nutrients, except heme iron and retinol, showed positive relationships with dietary fiber intake. Especially potassium and plant origin protein and calcium were highly correlated with dietary fiber intakes(r＞0.6). From these results, it is concluded that dietary fiber intakes of these sixth grade elementary school children were less than the standard reference and it is anticipated to decrease further in the future with increased incomes. Therefore, increased intakes of dietary fiber by elementary school children should be promoted through nutrition education, together with the development of cooking methods and recipes utilizing green vegetables and fruits.

• Applied Biological Chemistry
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• 제44권3호
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• pp.143-147
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• 2001

Hemoglobin(Hb) 가수분해도(degree of hydrolysis, DH)를 간편하고 신속하게 측정하고자 보편적으로 이용되는 TNBS법(trinitrobenzene sulfonic acid method)에 의한 가수분해도와 osmometer를 이용한 방법의 상관관계를 효소반응 조건에 따라 조사하였다. 다양한 ph 범위$(pH\;7.5{\sim}10.0)$에서 DH에 대한 두 방법의 상관계수($R^2$값)는 $0.974{\sim}0.991$로 매우 높은 값을 보였으며, 각각 측정한 DH 사이의 비율($DH_{OSM}/DH_{TNBS}$은 $1.438{\sim}1.656$의 범위에 있었다. Hb을 가수분해하여 heme-iron을 얻기 위한 특정 반응조건인 pH 7.5, $50^{\circ}C$에서 Esperase와 Fla-vourzyme을 각각 사용한 경우와 Esperase와 Flavourzyme을 혼용한 경우에서도 두 방법간의 DH 비율은 효소의 종류 및 처리방법에 무관하게 1.658을 나타내어 Esperase만을 사용한 경우와 매우 유사하였고 두 방법간의 상관계수는 0.982이었다. 따라서, 두 방법간의 상관관계식으로부터 osmometer를 이용한 Hb의 가수분해도를 간편하고 신속하게 측정할 수 있었다.

• Journal of Veterinary Science
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• 제23권5호
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• pp.74.1-74.16
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• 2022

Background: Previous studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood. Objectives: We aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action. Methods: Hemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model. Results: In Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model. Conclusions: We demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.

• BMB Reports
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• 제28권4호
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• pp.293-300
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• 1995

The radical centers detected in the reaction of metmyoglobin (MetMb) with hydrogen peroxide ($H_2O_2$) have been studied by using a spin trapping technique. A broad 5-line asymmetric electron spin resonance (ESR) spectrum, with $2A_{max}=4.07\;mT$ and $2A_{min}=2.97\;mT$, obtained after incubation of MetMb with $H_2O_2$ in the presence of a spin trap, 5,5-dimethyl pyrroline-N-oxide (DMPO) was gradually weakened with time and disappeared completely by 6 min after addition of guanidine-HCl (14 M). When a higher concentration (6 M) of the agent was added, the signal disappeared within 40 see and the DMPO/OH signal appeared immediately. Then, a new 8-line signal with similar intensities grew gradually and was fixed by 45 min, coexisting with the DMPO/OH signal. This new signal was found to be composite, consisting of two different radical species. One of the 6-line signals, with $a_N$ 1.49 mT and $a_H$ 0.988 mT, was assigned to the DMPO/phenoxyl radical adduct. The second 6-line signal with $a_N$ 1.55 mT and $a_H$ 2.22 mT was assigned to carbon-centered radical adduct. When 3,3,5,5-tetramethylpyrrolin-N-oxide (TMPO), was employed in the place of DMPO, another broad asymmetric 5-line signal was detected with $2A_{max}=3.99\;mT$ and $2A_{min}=3.04\;mT$, which is virtually identical to that obtained from the DMPO system The shape of the spectrum of the TMPO adduct changed drastically, with lapse of time resulting in a broad singlet after 40 min. The broad singlet was assigned to the porphyrin radical adduct. Incubation of globin with Fenton reagent in the presence of DMPO initially gave a DMPO/OH signal. Then, a new 12-line signal began to grow after one minute and fixed after 15 min. coexisting with the DMPO/OH signal, This 12-line signal was assigned to DMPO/phenoxyl with $a_N$ 1.47 mT, $a_{{\beta}H}$ 0.99 mT and $a_{{\gamma}H}$ 0.13 mT. A minor concentration of carbon-centered radical adduct was also detected. This radical composition is identical to that of guanidine HCl treated MetMb/DMPO/$H_2O_2$ system, indicating that the radical producing conditions are somehow common in both systems. Heme iron can be released by excess $H_2O_2$ in the MetMb/$H_2O_2$ system, providing for Fenton reagent. When MetMb was pretreated with tyrosine blocking agent, $KI_3$ the broad 5.line MetMb-derived signal was not detected in the MetMb/DMPO/$H_2O_2$ system, whereas no such effect was detected on such system of Hb in which the radical center was assigned to cysteine residue not tyrosine, indicating that tyrosine residue is a main radical center produced in the MetMb/$H_2O_2$ system Thus, the present data strongly support the previous indication that the apomyoglobin-derived radical center formed in the reaction of MetMb with $H_2O_2$ is a tyrosine residue.