• 한국동물학회지
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• 제32권1호
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• pp.34-39
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• 1989

젖산수소이탈효소 동위효소의 상대적값을 변화시키기 위하여 ouabain, strychnine sulfate, caffeine sodium benzoate 및 chlorpromazine hydrochloride을 웅성 mouse에 7일, 14일 및 21일간 복강주사하였다. 뇌, 심장 및 신장조직의 이 효소를 셀룰로우즈 strip상에서 전기영동한 후 densitometry에 의하여 동위효소들의 상대적 값을 구하였다. Ouabain은 뇌좆기에서만 B$_4$동위효소를 급격히 증가시켰다. 두가지 stimulant들은 뇌조직에서 $A_4$및 B$_4$동위효소의 상대적 값을 뚜렷하게 변화시킨 반면 deprossant는 뇌조직과 심장조직의 B$_4$동위효소를 제외하고는 동위효소의 재분포를 유도시키지 않았다. 이러한 실험적 결과들로부터 Na+ 이온이나 Ca++ 이온들의 세포질내 농도변화는 젖산수소이탈효소 동위효소의 재분포의 원인이 되지 않으며 원형질막의 체제가 이 효소의 조직특이성을 나타나게 하는 한가지 요인이 될 수 있다고 사료된다.

• 한국막학회:학술대회논문집
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• 한국막학회 2001년도 춘계 총회 및 학술발표회(한국막학회)
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• pp.104-107
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• 제26권1호
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• pp.134-142
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• 2013

The effect of modified atmosphere packaging (MAP; 30% $CO_2$+70% $N_2$ or 100% $N_2$) and an additive mixture (500 ppm rosemary extract, 3,000 ppm sodium acetate and 1,500 ppm calcium lactate) on the quality of pre-cooked hamburger patties during storage at $5^{\circ}C$ for 14 d was evaluated. The addition of the additive mixture reduced aerobic and anaerobic bacteria counts in both 30% $CO_2$-MAP (30% $CO_2$+70% $N_2$) and 100% $N_2$-MAP (p<0.05). The 30% $CO_2$-MAP was more effective to suppress the microbial growth than 100% $N_2$-MAP, moreover the 30% $CO_2$-MAP combined with additive mixture resulted in the lowest bacterial counts. The hamburger patties with additive mixture showed lower CIE $L^*$ and CIE $a^*$, and higher CIE $b^*$ than those with no additive mixture. The 30% $CO_2$-MAP tended to decrease the TBARS during storage regardless of the addition of additives. The use of 30% $CO_2$-MAP in combination with additives mixture was effective for maintaining the quality and extending the shelf-life of pre-cooked hamburger patties.

• The Korean Journal of Physiology
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• 제17권2호
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• pp.125-133
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• 1983

Red cell glycolytic intermediates, metabolites and metabolic ratios were studied. Glycolytic intermediates were measured in neutralized perchloric acid extracts of red cell suspensions after 3 hr incubation at $37^{\circ}C$ in the presence and absence of saponin. Adenosine triphosphate(ATP), adenosine diphosphate(ADP), pyruvate and lactate were measured by enzymatic procedures involving stoichiometric oxidation or reduction of a pyridine nucleotide. Glucose was determined using glucose oxidase after zinc hydroxide extraction. The redox state was calculated from the lactate dehydrogenase equilibrium. Adenosine triphosphatase activity(ATPase) was measured by determining the amount of phosphate released from ATP by washed erythrocyte membranes(ghost) during 20 min. incubation. Both total hydrolysis and the amount of hydrolysis that occured in the presence of ouabain were measured. The second measurement yields Mg-ATPase and represents nonspecific ATPase activity of the membranes. The difference between total and Mg-ATPase activity can be attributed to Na-K-ATPase. For the measurement of sodium fluxes, human erythrocytes were preincubated in $^{22}Na$ for 3 hr at $37^{\circ}C$, washed and suspended in a tracer-free medium. The amount of $^{22}Na$ transported out of cells at any time was determined by analysis of supernatant samples taken at various time after addition of the labeled cells to isotope-free medium. The cells and medium were separated and the radioactivity appearing in the medium was measured. From the total radioactivity in the suspension and the radioactivity appearing in the medium at known time, the rate constant for sodium release was computed. The results are summarized as follows: 1) ATP and ATP/ADP were found to increase at every concentration of saponin tested whereas ADP declined at every cone. of saponin. The increase in pyruvate and lactate were observed at every cone, of saponin and thus $NAD^+/NADH$ computed from pyruvate/lactate also increased. Glucose utilization was stimulated by saponin. 2) $Na^+-K^+-ATPase$ activities showed a biphasic response to saponin, first increasing in lower concentration and then decreasing in higher concentration of saponin. 3) The efflux of sodium was significantly increased by saponin in the range of 5 to 10 mg%. The stimulatory effect of saponin on the rate constants for active(ouabain-sensitive) sodium efflux was inhibited by addition of ouabain.

• 한국축산식품학회지
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• 제30권4호
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• pp.685-694
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• 2010

The present study investigated the combined effects of modified atmosphere packaging (MAP) and organic acid salts on the quality and shelf-life of Hanwoo ground beef patties. The ground beef containing 500 ppm of ascorbic acid was prepared with air-packaging (Air-P), high oxygen-MAP (70% $O_2$+30% $CO_2$/OxyMAP), and nitrogen-MAP (100% $N_2$/NitroMAP), in combination with organic acid salts (1500 ppm of sodium acetate and 500 ppm of calcium lactate). The samples were stored for 11 d at $5^{\circ}C$. The pH value of ground beef patties decreased during storage in all the treatments. The ground beef patties with organic acid salts showed relatively higher level of pH during storage compared with non-added patties (p<0.05). Lipid oxidation was accelerated in OxyMAP while it was delayed in NitroMAP treated with organic acid salts. Nitro-MAP treated with organic acid salts was effective in stabilizing the color characteristics of lightness (CIE $L^*$) and redness (CIE $a^*$) during storage. Oxygen content in MAP was shown to be a more important factor affecting color stability and lipid oxidation of ground beef than organic acid salts. The aerobic and anaerobic bacterial counts were reduced both in OxyMAP and NitroMAP (p<0.05), and the lactic acid bacteria was inhibited by Oxy-MAP (p<0.05). Coliform bacteria decreased during storage as pH value was decreased in all treatments. According to the sensory evaluation, the ground beef patties in NitroMAP showed the best quality among all treatments during storage. Therefore, Hanwoo ground beef patties added with sodium acetate and calcium lactate and packed with NitroMAP showed better quality characteristics than other treatments. This packaging method is recommended and could be utilized for packaging hanwoo ground beef patties for improving quality and extending shelf-life.

• Journal of Radiation Protection and Research
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• 제43권2호
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• pp.66-74
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• 2018

Background: Tumor response to anticancer therapies can much be influenced by microenvironmental factors. In this study, we determined the effect of these microenvironmental factors on DNA methylation using A549 human lung adenocarcinoma cell line. Materials and Methods: We subjected A549 cells to various conditions mimicking tumor microenvironment including hypoxia, acidosis (sodium lactate), oxidative stress ($H_2O_2$), bystander effect (supernatant from doxorubicin (Dox)-treated or irradiated cells), and immune cell infiltration (supernatant from THP-1 or Jurkat T cells). Genomic DNA was isolated from these cells and analyzed for DNA methylation. Clonogenic cell survival, gene expression, and metabolism were analyzed in cells treated with some of these conditions. Results and Discussion: We found that DNA methylation level was significantly decreased in A549 cells treated with conditioned media from Dox-treated cells or Jurkat T cells, or sodium lactate, indicating an active transcription. To determine whether the decreased DNA methylation affects radiation sensitivity, we exposed cells to these conditions followed by 6 Gy irradiation and found that cell survival was significantly increased by sodium lactate while it was decreased by conditioned media from Dox-treated cells. We further observed that cells treated with conditioned media from Dox-treated cells exhibited significant changes in expression of genes including BAX and FAS (involved in apoptosis), NADPH dehydrogenase (mitochondria), EGFR (cellular survival) and RAD51 (DNA damage repair) while sodium lactate increased cellular metabolism rather than changing the gene expression. Conclusion: Our results suggest that various tumor microenvironmental factors can differentially influence DNA methylation and hence radiosensitivity and gene expression in A549 cancer cells.

• 한국식품영양과학회지
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• 제30권5호
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• pp.858-864
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• 2001

젖산나트륨과 복합지방대체제가 저지방 볼로나의 품질과 냉장 중 저장안정성에 미치는 영향에 관하여 조사하였다. 유화형 볼로나를 대조구로 하여 일반성분을 분석한 결과 수분 600%, 지방 22% 및 단백질 함량이 12.4%를 함유하는, 반면 저지방 볼로나는 수분 73~76%, 지방 ~2% 및 단백질함량이 14~15%로 기존의 유화형 볼로나에 비하여 고단백, 저지방 소시지이었다. 저장 중 유화형 및 저지방(<3%) 볼로나의 유리수분량과 진공감량이 증가함에 따라 조직의 경도가 감소하였고(p<0.05), 총균수는 증가하였으나, 냉장 8주에 모두 가식 부위에 있었다. 젖산나트륨과 지방대체제를 첨가한 저지방 볼로나가 기존의 유화형 볼로나에 비해 가열 감량이 낮았으며(p<0.05) 경도를 비롯한 조직감은 높았다. 저지방 볼로나는 젖산나트륨의 첨가량이 증가할수록 유리수분량과 경도가 증가하였고, TBA값은 오히려 낮은 결과를 보여주었다. 냉장저장 중 젖산나트륨의 첨가에 따른 총균수에 영향이 나타났으며, 3.3% 젖산나트륨을 첨가한 처리구는 처리하지 않은 처리구보다 미생물의 성장억제 작용이 현저했다. 결론적으로 복합 지방대체제를 첨가한 저지방 볼로나의 젖산나트륨의 첨가량에 딸라 품질에 영향을 미쳤으며, 총균수와 TBA값을 낮출 수 있었다. 차후의 연구로 저지방 소시지에서 오염될 수 있는 Listeria monocytogenes 등과 같은 특정균을 일정균수($10^3$CFU/g) 접종함으로써 젖산나트륨의 특정미생물억제 효과에 관한 연구가 필요하다고 사료된다.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1433-1441
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• 2018

고강도 운동 시 산성화의 과정은 수소이온의 방출과 젖산 나트륨염을 형성하는 젖산의 생산 증가에 따른 것이라 설명되어져 왔다. 이 설명에 의하면, 젖산의 생산 비율이 세포내의 수소이온 완충능력을 초과하였을 때 세포의 수소이온 농도는 증가한다고 한다. 이러한 생화학적 과정을 젖산의 산성화라 한다. 이 이론에 따라 고강도 운동 시 젖산의 생산이 대사적 산성화와 피로의 원인이 되는 것으로 해석되어져 왔다. 그러나, 본 고찰에서는 젖산의 생산이 산성화와 피로의 원인이라는 어떠한 생화학적 근거가 없음을 명확히 제시하고 있다. 오히려 젖산의 생산은 해당과정에서 필요한 $NAD^+$의 지속적인 공급을 위해 필수적이며 수소이온을 소비하는 대사과정이다. 젖산의 축적은 세포와 혈중의 수소이온 농도의 증가를 알려주는 좋은 지표가 될 수는 있지만 그것이 산성화의 직접적인 원인은 아니다.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2002년도 정기총회 및 제29차 춘계국제 학술발표대회
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• pp.147-147
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• 2002

• The Korean Journal of Physiology and Pharmacology
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• 제11권2호
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• pp.45-55
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• 2007

We elucidated the effects of various components of ischemic medium on the outcome of simulated ischemia-reperfusion injury. Hypoxia for up to 12 hours induced neither apoptotic bodies nor LDH release. However, reoxygenation after 6 or 12 hours of hypoxia resulted in a marked LDH release along with morphological changes compatible with oncotic cell death. H9c2 cells were then subjected to 6 hours of simulated ischemia by exposing them to modified hypoxic glucose-free Krebs-Henseleit buffer. Lowered pH (pH 6.4) of simulated-ischemic buffer resulted in the generation of apoptotic bodies during ischemia, with no concomitant LDH release. The degree of reperfusion-induced LDH release was not affected by the pH of ischemic buffer. Removal of sodium bicarbonate from the simulated ischemic buffer markedly increased cellular damages during both the simulated ischemia and reperfusion. Addition of lactate to the simulated ischemic buffer increased apoptotic cell death during the simulated ischemia. Most importantly, concomitant acidosis and high lactate concentration in ischemic buffer augmented the reperfusion-induced oncotic cell death. These results confirmed the influences of acidosis, bicarbonate deprivation and lactate on the progression and outcome of the simulated ischemia-reperfusion, and also demonstrated that concomitant acidosis and high lactate concentration in simulated ischemic buffer contribute to the development of reperfusion injury.