• 제목/요약/키워드: Natural respiration

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사문암지대의 중금속 함유 낙엽의 분해에 관한 연구 I. Microcosm 실험 (Studies on the Decomposition of Leaf Litter Containing Heavy Metals in Andong Serpentine Area, Korea I. Microcosm Experiment)

  • 류새한;김정명;심재국
    • 환경생물
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    • 제27권4호
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    • pp.353-362
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    • 2009
  • This study attempted to compare the litter decomposition rate of Arundinella hirta and Miscanthus sinensis var. purpurascens which collected from serpentine soil acting potentially toxic concentration of heavy metals and non-serpentine soil by using the microcosm method for 192 days under constant humidity and $23^{\circ}C$. The contents of Ni, Fe, Mg and Cr in the serpentine and nonserpentine soil originated litter showed high differences between them. The litter samples from serpentine site have lower C/N than non-serpentine litter, but the soluble carbohydrate content was shown almost similar between two plant litter. The mass loss rates of leaf litter from serpentine area were slower than those from non-serpentine site. During the experimental period, the remained dry weight of A. hirta and M. sinensis var. purpurascens litter collected from serpentine site were 64.7%, 65.0% of initial dry weight and litter samples from non-serpentine site showed 54.2%, 50.7%, respectively. K and Na were leached rapidly at the initial decomposition periods, but Ca showed immobilization and other metal elements reserved at the decomposing litter for a long time. The decomposing A. hirta litter from non-serpentine soil showed higher values of $CO_2$ evolution, microbial biomass-C, and microbial biomass-N than those in serpentine soil originated litter acting nutrient stresses and exhibited rapid decay rate. The microbial biomass and microbial respiration of decaying litter were positively correlated with litter decomposition rate, and these relationships showed more rapid slope in non-serpentine soil originated litter than that in serpentine soil.

Oxidative Phosphorylation계에 의한 Phosphocreatine의 생성 기작 (Evidences for Functionally Direct Coupling between Mitochondrial Phosphocreatine Formation and Oxidative Phosphorylation)

  • 김일한
    • 자연과학논문집
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    • 제5권2호
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    • pp.3-11
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    • 1992
  • ADP 농도를 증가시킴에 따라 미토콘드리아에 의한 Phosphocreatine의 생성속도는 포화 경향을 보이면서 증진되었다. 이 조건에서 Phosphocreatne 생성 속도를 측정하여 가해준 ADP에 대한 Km값을 구해본 결과 0. 0185 mM 임을 알았고, 이 Km값은 미토콘드리아의 Oxidative Phosphoryla-tion게와 연계되지 않은 (추출한) 미토콘드리아 Creatine Kinase의 ATP에 대한 Km 값인 0. 21mM보다 훨씬 낮음을 알 수 있었다. 이 외에도 ADP 존재하에 Oxidative Phosphorylation에 의한 ATP 생성에 대한 Creatine Kinase의 활성의 영향을 살펴본 결과 이 조건에서 Phosphocreatine은 반응시간에 정비례하게 생성 되었으나, 생성된 ATP는 반응시간에 무관함을 보였다. 또한 Oxidative Phosphorylation에 의해 미토콘드리아 외부 Respiration 용액 내에 이 ATP가 축적되는 속도도 미토콘드리아 Creatine Kinase의 Phosphocreatine 생성과 무관함을 알수 있었다. 이상의 결과들은 Mitochondrial Creatine Kinase가 Oxidative Phosphorylation계와 기능적으로 밀접하게 연계되어 ATP가 아닌 Phophocreatine이 에너지 전달 물질로 직접 이용될 가능성을 시사해준다.

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효모에서 발현된 유전자 재조합 인간 성장호르몬의 일반 약리작용 (General Pharmacology of Recombinant Human Growth Hormone Expressed in Saccharomyces cerevisiae)

  • 이은방;신국현;정명숙;김운자;윤기영;김정근
    • 약학회지
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    • 제34권6호
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    • pp.439-446
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    • 1990
  • The general pharmacological actions of recombinant human growth hormone (rHGH) were investigated. It had hypothermic action but neither sedative nor analgesic action. No pharmacological effects were observed in isolated guinea pig ileum and tracheal muscle and rat fundus and uterus. Slight hypotensive action with no effect on respiration was revealed at a dose of 20 IU/kg i.v. of rHGH in rabbits. The rHGH exhibited a weak inhibitory action of glucose tolerance in normal rats, significantly lowered the blood glucose contents in adrenalectomized rats 20 min after i.v. administration (80IU/kg), and produced a significant inhibitory effect on in vitro glycerol release in epinephrine-stimulated epididymal fat pad segments of rats.

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Monitoring soil respiration using an automatic operating chamber in a Gwangneung temperate deciduous forest

  • Lee, Jae-Seok
    • Journal of Ecology and Environment
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    • 제34권4호
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    • pp.411-423
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    • 2011
  • This study was conducted to quantify soil $CO_2$ efflux using the continuous measurement method and to examine the applicability of an automatic continuous measurement system in a Korean deciduous broad-leaved forest. Soil respiration rate (Rs) was assessed through continuous measurements during the 2004-2005 full growing seasons using an automatic opening/closing chamber system in sections of a Gwangneung temperate deciduous forest, Korea. The study site was an old-growth natural mixed deciduous forest approximately 80 years old. For each full growth season, the annual Rs, which had a gap that was filled with data using an exponential function derived from soil temperature (Ts) at 5-cm depth, and Rs values collected in each season were 2,738.1 g $CO_2$ $m^{-2}y^{-1}$ in 2004 and 3,355.1 g $CO_2$ $m^{-2}y^{-1}$ in 2005. However, the diurnal variation in Rs showed stronger correlations with Ts (r = 0.91, P < 0.001 in 2004, r = 0.87, P < 0.001 in 2005) and air temperature (Ta) (r = 0.84, P < 0.001 in 2004, r = 0.79, P < 0.001 in 2005) than with deep Ts during the spring season. However, the temperature functions derived from the Ts at various depths of 0, -2, -5, -10, and -20 cm revealed that the correlation coefficient decreased with increasing soil depth in the spring season, whereas it increased in the summer. Rs showed a weak correlation with precipitation (r = 0.25, P < 0.01) and soil water content (r = 0.28, P < 0.05). Additionally, the diurnal change in Rs revealed a higher correlation with Ta than that of Ts. The $Q_{10}$ values from spring to winter were calculated from each season's dataset and were 3.2, 1.5, 7.4, and 2.7 in 2004 and 6.0, 3.1, 3.0, and 2.6 in 2005; thus, showing high fluctuation within each season. The applicability of an automatic continuous system was demonstrated for collecting a high resolution soil $CO_2$ efflux dataset under various environmental conditions.

계절변화에 따른 한국산 미꾸리, Misgurnus anguillicaudatus 피부의 조직학적 연구 (Seasonal Change of the Skin Morphology of Muddy Loach, Misgurnus anguillicaudatus(Cobitidae) from Korea)

  • 오민기;박종영
    • 한국어류학회지
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    • 제20권2호
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    • pp.90-96
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    • 2008
  • 미꾸리 M. anguillicaudatus의 등, 후두부, 체측 부위에서 적출한 피부조직의 형태를 분석하여 계절의 변화에 따른 각 부위 조직의 형태변화를 관찰하였다. 각 피부조직은 점액세포를 포함한 상피세포들로 구성된 표피층과 결합조직의 진피층으로 구성되어 있었으며, 표피와 진피층의 경계에 모세혈관이 분포하고 있었다. 표피의 middle layer에 분포하는 점액세포는 수온이 낮아짐에 따라 그 형태가 원형에서 타원형 또는 장타원형으로 변화하였고, 단위면적당 세포의 개수와 크기 및 분비량이 증가하였는데, 특히 후두부에서 그 변화양상이 가장 크게 나타났다. 또한, 등과 체측 부위의 비늘이 존재하는 진피층에서는 eosin에 염색되는 염기성 물질이 상당량 분비되어 진피층의 두께가 두꺼워지는 경향을 보였다. 계절변화에 따른 이러한 피부조직의 구조적 변화를 미꾸리의 동면, 피부호흡 및 점액의 기능과 관련하여 고찰하였다.

신우황청심원의 뇌허혈 및 중추신경계에 대한 약효 (Pharmacological Actions of New Woohwangchungsimwon Pill on Cerebral Ischemia and Central Nervous System)

  • 조태순;이선미;이은방;조성익;김용기;신대희;박대규
    • 약학회지
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    • 제41권6호
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    • pp.817-828
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    • 1997
  • In order to investigate pharmacological properties of New Woohwangchungsimwon Pill (NWCH) and Woohwangchungsimwon Pill(WCH), effects of NWCH and WCH on cerebral ischemia and central nervous system were compared. Cerebral ischemia insult was performed using unilateral carotid artery occlusion in Mongolian gerbils. The histological observations showed preventive effect of NWCH and WCH treatments with ischemia-induced brain damage. The ATP in brain tissue was decreased in vehicle-treated ischemic gerbils. This decrease was prevented by NWCH and WCH treatment. In contrast to what was seen with ATP, the lactate and lipid peroxide were both elevated in vehicle-treated ischemic gerbils. This elevation was inhibited by NWCH and WCH treatments. In central nervous system, NWCH and WCH had sedative effect in rotarod and spontaneous activity test, but no effects on the hexobarbital-induced sleeping time. And, NWCH and WCH had weak anticonvulsion effects in electric shock- and pentetrazol-induced convulsion test. NWCH and WCH increased the respiration rate, but decreased the respiration depth in rats. Furthermore, NWCH and WCH showed antistress effect. Our findings suggest that the pharmacological profiles of NWCH on cerebral ischemia and central nervous system are similar to that of WCH.

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논에 서식하는 미꾸라지 피부구조의 계절적 변화 (Seasonal Variation of Skin Structure in a Ricefield-dwelling Mud Loach Misgurnus mizolepis (Cobitidae) from Korea)

  • 오민기;박종영
    • 한국어류학회지
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    • 제21권2호
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    • pp.87-92
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    • 2009
  • 논에 서식하는 미꾸라지의 등, 체측, 후두부 피부조직에 대한 조직학적 연구를 통해 계절변화에 따른 점액세포의 변화여부를 조사하였다. 계절이 변화함에 따라 표피조직의 일반적인 형태에는 변화가 없었으나 상피조직에 존재하는 점액세포의 단위면적당 개수와 크기가 유동적으로 변화하였다. 비록 점액세포의 발달정도는 겨울철에 크게 증가하고 여름철에 감소하는 경향을 보였지만, 농지경작을 위해 관개를 실시한 봄(3~4월)과 추수를 위해 물을 배수시켜 미꾸라지의 피부가 공기에 노출되었던 가을(8~9월)에 점액세포의 월별 변화율이 가장 크게 조사되었다. 또한 농지 수온이 급격하게 높았던 6월에 점액세포가 일시적으로 발달하는 모습이 관찰되었다. 계절에 따른 점액세포의 변화는 유동적인 농지환경에 대한 능동적 행동이자 피부호흡을 하기 위함으로 여겨진다.

Ginsenosides attenuate bioenergetics and morphology of mitochondria in cultured PC12 cells under the insult of amyloid beta-peptide

  • Kwan, Kenneth Kin Leung;Yun, Huang;Dong, Tina Ting Xia;Tsim, Karl Wah Keung
    • Journal of Ginseng Research
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    • 제45권4호
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    • pp.473-481
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    • 2021
  • Background: Mitochondrial dysfunction is one of the significant reasons for Alzheimer's disease (AD). Ginsenosides, natural molecules extracted from Panax ginseng, have been demonstrated to exert essential neuroprotective functions, which can ascribe to its anti-oxidative effect, enhancing central metabolism and improving mitochondrial function. However, a comprehensive analysis of cellular mitochondrial bioenergetics after ginsenoside treatment under Aβ-oxidative stress is missing. Methods: The antioxidant activities of ginsenoside Rb1, Rd, Re, Rg1 were compared by measuring the cell survival and reactive oxygen species (ROS) formation. Next, the protective effects of ginsenosides of mitochondrial bioenergetics were examined by measuring oxygen consumption rate (OCR) in PC12 cells under Aβ-oxidative stress with an extracellular flux analyzer. Meanwhile, mitochondrial membrane potential (MMP) and mitochondrial dynamics were evaluated by confocal laser scanning microscopy. Results: Ginsenoside Rg1 possessed the strongest anti-oxidative property, and which therefore provided the best protective function to PC12 cells under the Aβ oxidative stress by increasing ATP production to 3 folds, spare capacity to 2 folds, maximal respiration to 2 folds and non-mitochondrial respiration to 1.5 folds, as compared to Aβ cell model. Furthermore, ginsenoside Rg1 enhanced MMP and mitochondrial interconnectivity, and simultaneously reduced mitochondrial circularity. Conclusion: In the present study, these results demonstrated that ginsenoside Rg1 could be the best natural compound, as compared with other ginsenosides, by modulating the OCR of cultured PC12 cells during oxidative phosphorylation, in regulating MMP and in improving mitochondria dynamics under Aβ-induced oxidative stress.

Effect of Slowly Forced Expiration on Abdominal Muscle Activity During Cross Knee Curl-Up Exercise

  • Yoon, Tae-Lim;Kim, Ki-Song
    • 한국전문물리치료학회지
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    • 제21권1호
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    • pp.63-69
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    • 2014
  • Cross knee curl-up is an ideal variation of abdominal curl up exercise to strengthen abdominal musculature without excessive lumbar flexion which can increase the loads on the disc and ligaments. In addition, slowly forced expiration can facilitate the activation of the abdominal musculature. The purpose of this study was to determine the effects of slowly forced expiration on activity of abdominal muscles, such as rectus abdominis (RA), external oblique (EO), and transverse abdominis/internal oblique (TrA/IO), while cross knee curl-up. Eleven young and healthy subjects (6 males and 5 females) participated. All subjects performed the cross knee curl-up slowly forced expiration and natural breathing. Paired t-test was performed in normalized electromyogram (EMG) muscle activity of the bilateral RA, EO, and TrA/IO to compare the differences between the cross curl-up with slowly forced expiration and natural breathing. Statistical significance was set at .05. There were no significant differences in normalized EMG muscle activity of the bilateral RA, EO, and TrA/IO between the cross curl-up with slowly forced expiration and natural breathing. The finding of this study designates that slowly forced expiration does not induce increasing activity of abdominal muscle in cross knee curl-up; hence, learning step of breathing control might not be necessary to strengthen abdominal muscle in cross knee curl-up.