• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.6
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• pp.322-330
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• 2003

The unicellular green alga Haematococcus pluvialis has recently attracted great inter-est due to its large amounts of ketocarotenoid astaxanthin, 3,3'-dihydroxy-${\beta}$,${\beta}$-carotene-4,4'-dione, widely used commercially as a source of pigment for aquaculture. In the life cycle of H. pluvialis, astaxanthin biosynthesis is associated with a remarkable morphological change from green motile vegetative cells into red immotile cyst cells as the resting stage. In recent years we have studied this morphological process from two aspects: defining conditions governing astaxanthin biosynthesis and questioning the possible function of astaxanthin in protecting algal cells against environmental stress. Astaxanthin accumulation in cysts was induced by a variety of environmental conditions of oxidative stress caused by reactive oxygen species, intense light, drought, high salinity, and high temperature. In the adaptation to stress, abscisic acid induced by reactive oxygen species, would function as a hormone in algal morphogenesis from veget ative to cyst cells. Furthermore, measurements of both in vitro and in vivo antioxidative activities of astaxanthin clearly demonstrated that tolerance to excessive reactive oxygen species is greater in astaxanthin-rich cysts than in astaxanthin-poor cysts or astaxanthin-less vegetative cells. Therefore, reactive oxygen species are involved in the regulation of both algal morph O-genesis and carotenogenesis, and the accumulated astaxanthin in cysts can function as a protective agent against oxidative stress damage. In this study, the physiological roles of astaxanthin in stress response and cell protection are reviewed.

• Journal of Photoscience
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• v.9 no.2
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• pp.9-12
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• 2002

Circadian rhythms can be seen in a variety of physiological functions in insects. Light is a powerful zeitgeber not only synchronizing but also modulating the rhythm to adjust insect's temporal structure to seasonal changes in the environmental cycle. There are two general effects of the length of light phase within 24 hr light cycles on the circadian rhythms, i.e., the modulation of free-running period and the waveform. Since the photoperiodic modulation of the free-running period is induced even in the clock mutant flies, per$\^$s/, the free-running period is not fully determined genetically. In crickets, the ratio of activity (a) and rest phase (p) under the constant darkness (DD) is clearly dependent on the photoperiod under which they have been kept. When experienced the longer photoperiod it becomes smaller. The magnitude of change in a/p-ratio is dependent on the number of cycles they experienced. The neuronal activity of the optic lobe in DD shows the a/p-ratio changing with the preceding photoperiod. These data suggest that a single circadian pacemaker stores and maintains the photoperiodic information and that there is a system that accumulates the effects of single photoperiod to cause greater effects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.199-205
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• 2009

It is unclear whether Fructus ligustri Lucidi (FLL) extract anti-proliferative effect in human glioma cells. The present study was therefore undertaken to examine the effect of FLL on cell viability and to determine the underlying mechanism in A172 human glioma cells. Cell viability and cell death were estimated by MTT assay and trypan blue exclusion assay, respectively. Apoptosis was measured by Annexin-V binding assay and cell cycle analysis. Activation of kinases and caspase-3 was estimated by Western blot analysis. FLL resulted in apoptotic cell death in a dose- and time-dependent manner. FLL-induced cell death was not associated with reactive oxygen species generation. Western blot analysis showed that FLL treatment caused down-regulation of PI3K/Akt pathway, but not ERK. The PI3K/Akt inhibitor LY984002 sensitized the FLL-induced cell death and overexpression of Akt prevented the cell death. FLL induced caspase-3 activation and the FLL-induced cell death was prevented by caspase inhibitors. These findings indicate that FLL results in a caspase-dependent cell death through a P13K/Akt pathway in human glioma cells. These data suggest that FLL may serve as a potential therapeutic agent for malignant human gliomas.

• Molecules and Cells
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• v.20 no.1
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• pp.97-104
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• 2005

To investigate apoptosis in HC11 mammary epithelial cells, we compared the gene expression profiles of actively growing and serum-starved apoptotic cells using a mouse apoptosis gene array and $^{33}P$-labeled cDNA prepared from the RNA of the two cultures. Analysis of the arrays showed that expression of several genes such as clusterin, secreted frizzled related protein mRNA (sFRP-1), CREB-binding protein (CBP), and others was higher in the apoptotic cells whereas expression of certain genes including survivin, cell division cycle 2 homolog A (CDC2), and cyclin A was lower. These expression patterns were confirmed by RT-PCR and/or Northern analyses. We compared the expression of some of these genes in the mouse mammary gland under various physiological conditions. The expression levels of genes (clusterin, CBP, and M6P-R) up-regulated in apoptotic conditions were higher at involution than during lactation. On the other hand, genes (Pin, CDC2) downregulated in apoptotic conditions were relatively highly expressed in virgin and pregnant mice. We conclude that certain genes such as clusterin, sFRP-1, GAS1 and CBP are induced in apoptotic mammary epithelial cells, and others are repressed. Moreover, the apoptosis array is an efficient technique for comparing gene expression profiles in different states of the same cell type.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.209-212
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• 2003

A wide variety of cancer chemotherapeutic agents have been shown to induce programmed cell death (PCD, apoptosis) in various tumor cell fines in vitro. This study was performed to know how ginsenoside Rc affect on SK-MEL-28 cell line, and how they induce the apoptosis. SK-MEL-28 cell lines were treated with various concentrations of ginsenoside Rc and cultured for various times. At cell cycle analysis, cells arrested at G2/M phase by ginsenoside Rc and apotosis percentage increased along with increasing concentration and time. TUNEL assay was performed to know whether SK-MEL-28 cell fine die as apoptosis or necrosis by ginsenoside Rc. As a result, fluorescence increased along with increasing time and concentration. Fas expressed on SK-MEL-28 cell lines membrane by ginsenoside Rc was identified using flow cytometer. Ginsenoside Rc induced apoptosis against SK-MEL-28 cell fines, and the apoptosis mechanism was identified as Fas-mediated apotosis.

• Biomolecules & Therapeutics
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• v.21 no.2
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• pp.97-106
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• 2013

Chronic hepatitis C virus (HCV) infection is responsible for the development of liver cirrhosis and hepatocellular carcinoma. HCV core protein plays not only a structural role in the virion morphogenesis by encapsidating a virus RNA genome but also a non-structural role in HCV-induced pathogenesis by blocking innate immunity. Especially, it has been shown to regulate JAK-STAT signaling pathway through its direct interaction with Janus kinase (JAK) via its proline-rich JAK-binding motif ($^{79}{\underline{P}}GY{\underline{P}}WP^{84}$). However, little is known about the physiological significance of this HCV core-JAK association in the context of the virus life cycle. In order to gain an insight, a mutant HCV genome (J6/JFH1-79A82A) was constructed to express the mutant core with a defective JAK-binding motif ($^{79}{\underline{A}}GY{\underline{A}}WP^{84}$) using an HCV genotype 2a infectious clone (J6/JFH1). When this mutant HCV genome was introduced into hepatocarcinoma cells, it was found to be severely impaired in its ability to produce infectious viruses in spite of its robust RNA genome replication. Taken together, all these results suggest an essential requirement of HCV core-JAK protein interaction for efficient production of infectious viruses and the potential of using core-JAK blockers as a new anti-HCV therapy.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.1
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• pp.1-6
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• 2006

This study was performed to evaluate sleep efficiencies and conditions for comfortable sleep based on the analysis of EEGs and MST under four thermals conditions. Five female subjects who have similar life cycle and sleep patterns were participated for the sleep experiment. Their age was from 20 to 22 years old. They were healthy, and had regular sleep with consistent bed and wakeup time. It was checked whether they had a good sleep before the night of experiment. Experiments were performed in an environmental chamber of $4.1\times4.9\times2.7m$ size. EEGs were obtained from C3-A2 and C4-Al electrode sites. Sleep stages were classified, then TST, SWS latency and SWS/TST were calculated for the evaluation for sleep efficiencies on thermal conditions. As results, it was concluded that indoor thermal environments of $24\~26^{\circ}C$ was the best for comfortable and deep sleep.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.725-732
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• 2008

From old times, we think it is very important to become pregnancy with child and to give birth healthy, as the human gives not just body but also spirit. When we judge pregnancy, we usually check lady's menstrual cycle. But it is too difficult to diagnosis as pregnancy only check that. Therefore feeling pulse has been made use of knowing pregnancy or not, monthly pregnancy states and childbirth. "Haung-di-nei-jing" mentions pregnancy-pulse, for example, "Yin beats and Yang distinguishes", "Shou-shao-yin-mai moves severely", "Lady has some symptoms, but no Xie-mai". Since then, there are many opinions of schools about that. For the period of pregnancy, pulse shows special features, according as the symptoms differ from month to month. When pregnant woman is just about to bear, her pulse changes unusually. In oriental medicine, it is called as Li-jing-mai. Pregnancy-pulse is worth refering to pursue a clinical examination.

• ALGAE
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• v.26 no.1
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• pp.3-20
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• 2011

The physiology of the unicellular green alga Dunaliella salina in response to abiotic stress has been studied for several decades. Early D. salina research focused on its remarkable salinity tolerance and ability, upon exposure to various abiotic stresses, to accumulate high concentrations of $\beta$-carotene and other carotenoid pigments valued highly as nutraceuticals. The simple life cycle and growth requirements of D. salina make this organism one of the large-scale commercially exploited microalgae for natural carotenoids. Recent advances in genomics and proteomics now allow investigation of abiotic stress responses at the molecular level. Detailed knowledge of isoprenoid biosynthesis mechanisms and the development of molecular tools and techniques for D. salina will allow the improvement of physiological characteristics of algal strains and the use of transgenic algae in bioreactors. Here we review D. salina isoprenoid and carotenoid biosynthesis regulation, and also the biotechnological and genetic transformation procedures developed for this alga that set the stage for its future use as a production system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.4
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• pp.307-312
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• 2007

This study was performed to evaluate sleep efficiencies and conditions for comfortable sleep based on the analysis of sleep efficiency and MST under four thermals conditions ($22^{\circ}C,\;24^{\circ}C,\;26^{\circ}C,\;30^{\circ}C$). Five female subjects who have similar life cycle and sleep patterns were participated for the sleep experiment. Their age was from 20 to 22 years old. They were healthy, and had regular sleep with consistent bed and wakeup time. It was checked whether they had a good sleep before the night of experiment. Experiments were performed in an environmental chamber using thermo-hygrostat. The physiological signal (EEG) for sleep stage were obtained from C3-A2 and C4-Al electrode sites. Sleep stages were classified, then SWS latency and SWS/TST were calculated for the evaluation for sleep efficiencies on thermal conditions. As results, mean skin temperature for comfort sleeping was $34.5{\sim}35.4^{\circ}C$. Considering sleep efficiency and mean skin temperature, indoor room temperature of upper limit was $28.1^{\circ}C$.