• Journal of Ginseng Research
• /
• 제11권2호
• /
• pp.101-110
• /
• 1987

인삼(Panax ginseng C.A. Meyer) 엽소병에서 chorophyll의 bleaching 현상에 대한 생리적 반응기작을 조사, 분석한 결과 chorophyll의 bleaching 현상은 singlet oxygen ($^1O_2$)에 의한 photooxidation 과 catalase와 peroxidase의 inactivation에 의한 $H_2O_2$의 autooxidation이었다. Chorophyll의 bleaching 현상에 원인으로 추리된 $H_2O_2$를 농도별로 인삼잎 절편에 처리하였던 바, chorophyll의 함량과 chorophyll의 흡수스펙트럼은 자연광 처리시 유발된 bleaching 현상과 일치하였으며, saponin 첨가로 인하여 bleaching 현상은 현저히 촉진되었다.

• Preventive Nutrition and Food Science
• /
• 제19권4호
• /
• pp.363-366
• /
• 2014

Zinc is considered to be involved in maintaining healthy vascular condition. Atherosclerotic calcification of vascular smooth muscle cells (VSMCs) occurs via the mechanism of cell death; therefore, cell viability is a critical factor for preventing VSMC calcification. In this study, we tested whether zinc affected VSMC viability under both normal physiological non-calcifying (0 mM P) and atherosclerotic calcifying conditions (3 and 5 mM P), since VSMC physiological characters change during the VSMC calcification process. The study results showed that an optimal zinc level ($15{\mu}M$) restored the decreased VSMC viability which was induced under low zinc levels (0 and $1{\mu}M$) and calcifying conditions (3 and 5 mM P) at 9 and 15 days culture. This zinc-protecting effect for VSMC viability is more prominent under atherosclerotic calcifying condition (3 and 5 mM P) than normal condition (0 mM P). Also, the increased VSMC viability was consistent with the decreased Ca and P accumulation in VSMC cell layers. The results suggested that zinc could be an effective biomineral for preventing VSMC calcification under atherosclerotic calcifying conditions.

• 대한한의진단학회지
• /
• 제16권3호
• /
• pp.33-40
• /
• 2012

Objectives: Existing cardiovascular simulators are used to evaluate artificial organs such as artificial hearts, prosthetic valves, and artificial blood vessels, and pulses are typically triggered using artificial hearts. However, the forms of pulse waves vary according to the location of arteries, and for precise assessment of artificial blood vessels, the development of simulators that generate diverse pressure pulse waves is necessary. This study developed a novel cardiovascular simulator that generates different forms of pulse waves. Methods: This simulator consists of a stepping motor, a slider-crank mechanism that transforms the rotation movement of a motor into the straight-line motion of a piston, a piston that generates pulsatile flows, a water tank that supplies fluids, an elastic tube made of silicon, and a device that adjusts the terminal resistance of fluids. Results & Conclusion: This study examined motor rotation and its operation under conditions similar to the physiological conditions of the heart. The simulator developed in this study produced diverse forms of waves, and the generated pressure waves well satisfied physiological conditions.

• 한국작물학회지
• /
• 제49권2호
• /
• pp.126-130
• /
• 2004

This study is to identify the physiological traits of submergence-tolerant varieties of rice plants (Oryza sativa L.) in Yeongnam area, southeastern part of Korea, where the reduction of rice yield due to submergence is remarkably severe. In the present study, two tolerant varieties of rice plants were selected from over 30 rice varieties grown in under a 10-day period. The tolerant varieties selected from a submerged paddy field. As a control, one intolerant variety of rice plant was chosen. Of the tolerant variety Samgangbyeo, rather than Haepyungbyeo, had a lower dissolved oxygen consumption and maintained a higher dry weight than the intolerant variety. The leaf photosynthetic rates (LPS) of the two tolerant varieties were significantly higher than that of the intolerant-variety after four days of submergence treatment. These results indicate that lower dissolved oxygen consumption in a limited pool is prevented by ethylene formation in the tolerant varieties, which may be a mechanism of submergence tolerance.

• 동의생리병리학회지
• /
• 제20권5호
• /
• pp.1285-1289
• /
• 2006

Hominis placenta (HP) has been used as an agent for promoting physiological function in traditional asian medicine. The present study was peformed to investigate whether HP acupuncture treatment in an experimental tumor mice model inhibit tumor growth through immunomodulatory effects. Mice were inoculated subcutaneously with colon26-L5 cells on the back. Three days after tumor inoculation, HP herbal acupuncture treatment was conducted on BL18 acupoint every other day for three weeks. HP Herbal acupuncture treatment significantly suppressed the primary tumor growth and prolonged survival rate. To evaluate immunomodulatory effect of HP acupuncture, splenocytes proliferation assay, fluorescence-activated cell sorting (FACS) and ELISA for IFN- ${\gamma}$, and IL-4 cytokine level. HP herbal acupuncture enhanced the mitogenic activity of Balb/c whole splenocytes induced by various mitogenic stimuli and increased immune cell population such as T cell, B cell, Th cell, Tc cell and Macrophages. HP herbal acupuncture caused a marked increase of production of Th1 cytokine (IFN- ${\gamma}$ ,) and decrease of production of Th2 cytokine (IL-4). These results indicated that HP herbal acupuncture suppresses tumor growth through a mechanism leading to a Th1 dominant immune state.

• Plant Biotechnology Reports
• /
• 제5권4호
• /
• pp.309-315
• /
• 2011

Rice grown in anaerobic waterlogged soil accumulates ammonium as a major source of nitrogen (N). We have compared the physiological symptoms of rice seedlings subjected to N-starvation stress with those receiving sufficient N, based on measurements of shoot/root length and weight and an analysis of protein expression patterns. N starvation marginally increased root growth but notably decreased shoot biomass. N uptake was reduced by >50% in the roots and shoots of N-starved seedlings. To better understand the mechanism of N starvation in rice, we performed a comparative proteome analysis of proteins isolated from rice leaves. Twenty-five differentially expressed proteins were analyzed by matrixassisted laser desorption/ionization time-of-flight (TOF) mass spectrometry and electron spray ionization quadrupole TOF. Functional analysis of the N-starvation response proteins suggested their involvement in protein synthesis and fate, metabolism, and defense. These results indicate that these proteins may play important roles in regulating the plant's complex adaptation responses for N use during N starvation. The proteins may be useful for further characterization of protein function in plant N nutrition.

• 한국초지조사료학회지
• /
• 제43권3호
• /
• pp.177-182
• /
• 2023

Iron (Fe) is a vital element for plants and other organisms, involving in several physiological processes including respiration, chlorophyll biosynthesis, and photosynthesis. Unfortunately, how Fe accumulation regulates in response to light quality has not been well established in plants. Therefore, the aim of the study was to explore the mechanism of Fe homeostasis by light quality. In this study, we found morpho-physiological attributes were significantly improved in response to blue (λmax: 450) compared to white (λmax: 500) and red (λmax: 660) light. The root-shoot length, plant biomass, photosynthesis efficiency (Fv/Fm) and leafgreen (SPAD) significantly declined in response to white and red light. However, these parameters were improved and iron deficiency was substantially alleviated by blue light exposure in alfalfa seedlings. This study might be useful to the forage breeders and farmers for improving alfalfa yield and nutritional benefits.

• The Korean Journal of Physiology
• /
• 제22권2호
• /
• pp.179-187
• /
• 1988

This study was conducted to investigate the effects of epinephrine and norepinephrine on basal gastric acid secretion and plasma gastrin and secretin concentration in the conscious rat. One hundred and eighty-four albino rats with gastric cannula were used after 18 hours or more of fast, with water ad libitum. In a restraint cage for collection of gastric juice, physiological saline (0.9% NaCl) was continuously infused into the jugular vein through a catheter for one hour at a rate of 1 ml/hr (control period). Immediately after the control period, epinephrine (1, 2, 4, 8 and $16{\mu}g/ml/hr)$, norepinephrine (1, 2, 4, 8 and $16{\mu}g/ml/hr)$ or physiological saline (1 ml/hr) was infused for another one hour. Gastric juice was collected at one hour interval for two hours infusion period. Adrenergic antagonists, phentolamine and propranolol were injected into the jugular vein 5 min prior to the infusion of epinephrine or norepinephrine at a dose of 0.2 mg/0.1 ml. Blood was sampled from the jugular vein for the radioimmunoassay of plasma gastrin and secretin after the collection of gastric juice. The results were as follows: 1) Both epinephrine and norephinephrine significantly increased gastric acid output in a dosedependent manner. 2) The effects of epinephrine and norepinephrine on the gastric acid secretion were antagonized by the pretreatment with phentolamine and propranolol. 3) Plasma gastrin and secretin concentrations were not significantly affected by the intravenous infusion of epinephrine and norepinephrine. It can be inferred from the above results that epinephrine and norepinephrine facilitate gastric acid secretion in conscious rats and the mechanism of which is attributed to ${\alpha}\;and\;{\beta}$ adrenergic receptors rather than gastrin and secretin.

• Bulletin of the Korean Chemical Society
• /
• 제35권3호
• /
• pp.858-864
• /
• 2014

Recently, many researches have shown that even photosynthetic light-harvesting pigment-protein complexes can have quantum coherence in their excitonic energy transfer at cryogenic and physiological temperatures. Because the protein supplies such noisy environment around pigments that conventional wisdom expects very short lived quantum coherence, elucidating the mechanism and searching for an applicability of the coherence have become an interesting topic in both experiment and theory. We have previously studied the quantum coherence of a phycocyanin 645 complex in a marine algae harvesting light system, using Poisson mapping bracket equation (PBME). PBME is one of the applicable methods for solving quantum-classical Liouville equation, for following the dynamics of such pigment-protein complexes. However, it may suffer from many defects mostly from mapping quantum degrees of freedom into classical ones. To make improvements against such defects, benchmarking targets with more accurately described dynamics is highly needed. Here, we fall back to reduced hierarchical equation of motion (HEOM), for such a purpose. Even though HEOM is known to applicable only to simplified system that is coupled to a set of harmonic oscillators, it can provide ultimate accuracy within the regime of quantum-classical description, thus providing perfect benchmark targets for certain systems. We compare the evolution of the density matrix of pigment excited states by HEOM against the PBME results at physiological temperature, and observe more sophisticated changes of density matrix elements from HEOM. In PBME, the population of states with intermediate energies display only monotonically increasing behaviors. Most importantly, PBME suffers a serious issue of wrong population in the long time limit, likely generated by the zero-point energy leaking problem. Future prospects for developments are briefly discussed as a concluding remark.

• 한국음향학회:학술대회논문집
• /
• 한국음향학회 1999년도 학술발표대회 논문집 제18권 1호
• /
• pp.269-273
• /
• 1999

Combination of mental stress task with noise background is a traditional tool employed in psychophysiology. However, intensity of background noise is a factor affecting both performance on test and psychophysiological responses associated with stress evoked by mental load in noisy environment. In the current study on 7 subjects we analyzed the influence of white noise (WN) intensity (55, 70, and 85 dB[A] ) on psychophysiological responses during word recognition test performed on noise background. There were recorded following physiological variables: electrodermal activity (EDA) , namely, skin conductance level (SCL), skin conductance response (SCR) amplitude (SCR-A), rise time and total number of SCRs (N-SCR); cardiovascular activity, e.g., heart rate (HR), respiratory sinus arrhythmia (RSA) index, pulse transit time (PTT), finger pulse volume (PV), skin temperature (SKT) and respiratory activity, such as respiration rate (RESP-R) and inspiration wane amplitude (RESP-A) during baseline resting state and 40 s long performance on 3 similar Korean word recognition tests with different WN intensity (55, 70, and 85 dB). Electrodermal responses (SCR-A, SCL, N-SCR) demonstrated gradual increment with increased intensity of noise, and this increase of response magnitude with higher intensity of noise was typical also for r skin temperature (phasic SKT decrease) and pulse volume (phasic and tonic PV decrease). However, some cardiovascular and respiratory responses did not exhibit same tendency of gradual increase of reactivity , namely HR, as well as RESP-R and RESP-A showed decrement of response magnitudes. Important finding in terms of cardiovascular reactivity was that 55 and 70dB evoked similar profiles, while 85dB WN resulted in significantly different profile of reactions, suggesting that there exists a threshold level after which intensive auditory stimulation elicits psychophyslological responses pattern of different quality. There are discussed potential autonomic mechanism involved in mediation of observed physiological responses.