• Title/Summary/Keyword: Cell Resistance

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Antioxidant Activities of Hot Water Extract from Cornus walteri Wanger against Oxidative Stress Induced by tert-Butyl Hydroperoxide in HepG2 Cells (tert-Butyl Hydroperoxide로 산화 스트레스가 유도된 HepG2 세포에서 말채나무 열수추출물의 항산화 활성)

  • Yeon, Seong Ho;Ham, Hyeonmi;Sung, Jeehye;Kim, Younghwa;Namkoong, Seulgi;Jeong, Heon-Sang;Lee, Junsoo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1525-1532
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    • 2013
  • The objective of this study was to investigate the effect of hot water extract from Cornus walteri Wanger (CWE) on tert-butyl hydroperoxide (TBHP)-induced oxidative stress in HepG2 cells. Generation of reactive oxygen species (ROS), concentrations of cellular lipid peroxidation products and reduced glutathione, and antioxidant enzyme activity were used as biomakers of cellular oxidative status. Cells pretreated with CWE (25~200 ${\mu}g/mL$) showed an increased resistance to oxidative stress in a dose-dependent manner, as revealed by a higher percentage of surviving cells compared to control cells. ROS generation induced by TBHP was significantly reduced when cells were pretreated with 200 ${\mu}g/mL$ CWE for 4 h. Pretreatment with CWE (5~50 ${\mu}g/mL$) prevented the decrease in reduced glutathione and the increase in malondialdehyde and ROS evoked by TBHP in HepG2 cells. Finally, CWE pretreatments prevented the significant increase of glutathione peroxidase, catalase, glutathione reductase, and superoxide dismutase activities induced by TBHP. These results show that CWE has significant protective ability against a TBHP-induced oxidative insult and that the modulation of antioxidant enzymes by CWE may have an important antioxidant effect on TBHP-induced oxidative stress in HepG2 cells.

Gender Differences in Physiological Effects of a Transient Exposure to Experimental Noise

  • Hyun, Kyung-Yae;Kim, Chong-Rak;Kim, Hwa-Il;Kim, Young-Hwal;Choi, Seok-Cheol
    • Biomedical Science Letters
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    • v.12 no.4
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    • pp.375-383
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    • 2006
  • The physiological responses following stress are different in individual or personality. We performed this study to clarify gender differences in influences of noise stress on physiological factors. 70 healthy subjects, which was divided man (n=30) and woman (n=40) groups, were exposed to 85 decibels of excavator noise for 15 minutes. Cardiac factors such as heart rate (HR), systolic and diastolic blood pressures (SBP and DBP, respectively), and heart rate-systolic pressure product (RPP) were determined. Transcranial Doppler ultrasound (TCD) was used to measure mean blood flow velocity (Vm), pulsatility index (PI), and resistance index (RI) in the middle, anterior and posterior cerebral arteries (MCA, ACA and PCA, respectively) before and during noise exposure. Cortisol level and hematological variables were also measured before (baseline) and immediately after the end of noise exposure. In the both groups HR, SBP, and RPP significantly decreased during noise exposure (P<0.05) but not significantly different between two groups (P>0.05). Vms of three cerebral arteries in man group decreased, whereas Vm of PCA in woman group fell during noise exposure (P<0.05). Vm, PI and RI in MCA and ACA during noise exposure were low in man group compared with woman group (P<0.05). Vm of PCA was low, whereas PI and RI of PCA were high in man group compared with woman group during noise exposure (P<0.05). Total leukocyte and red blood cell (RBC) counts slightly decreased during noise exposure but not significant (P>0.05). Levels in hematological variables decreased but not significant changed following noise exposure. Decreased rate of total leukocyte in man group was higher (P<0.05). Cortisol levels in the both groups decreased immediately after the end of noise exposure, while the decreased rate in man group was greater than that in woman group (p<0.05). These findings indicate that a transient exposure to experimental excavator noise may cause decreased changes in cardiac factors, cerebral hemodynamics and cortisol levels and the changes may be greater in men than in women.

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The Influence of the Sympathetic Nervous System on the Development and Progression of Cancer (교감신경계가 암의 발전과 진행에 미치는 영향)

  • Park, Shin-Hyung;Chi, Gyoo-Yong;Choi, Yung Hyun
    • Journal of Life Science
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    • v.28 no.1
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    • pp.116-129
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    • 2018
  • Living creatures possess long-conserved mechanisms to maintain homeostasis in response to various stresses. However, chronic and continuous exposure to stress can result in the excessive production of stress hormones, including catecholamines, which have harmful effects on health. Studies on the relationship between the sympathetic nervous system (SNS) and cancer have been conducted based on the traditional hypothesis that stress can promote cancer progression. Many preclinical and epidemiological studies have suggested that the regulation of ${\beta}$-adrenergic signaling, which mediates SNS activity, can suppress the progression of solid tumors. SNS activation has highly pleiotropic effects on tumor biology, as it stimulates oncogenes, survival pathways, the epithelial - mesenchymal transition, and invasion. Moreover, it inhibits DNA repair and programmed cell death and regulates the tumor microenvironment, including immune cells, endothelial cells, the extracellular matrix, mesenchymal cells, and adipocytes. Although targeted therapies on the molecular basis of tumor proliferation are currently receiving increased attention, they have clinical limitations, such as the compensatory activation of other signaling pathways, emergence of drug resistance, and various side effects, which raise the need for pleiotropic cancer regulation. This review summarizes the effects of the SNS on the development and progression of cancer and discusses the clinical perspectives of ${\beta}$-blockade as a novel therapeutic strategy for this disease.

The Anti-obesity Effect of Aureobasidium pullulans SM-2001 Extract (Polycan®) on 3T3-L1 Preadipocytes and Adipocytes (3T3-L1세포에서 흑효모 SM-2001 추출물(Polycan®)의 항비만 효과)

  • Kim, Young-Suk;Lim, Jong-Min;Ku, Bon-Hwa;Moon, Seung-Bae;Cho, Hyung-Rae;Lee, Seon-Min;Kwon, Jung-Hee
    • Journal of Life Science
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    • v.30 no.10
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    • pp.835-843
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    • 2020
  • Obesity, the world's leading metabolic disease, is a serious health problem in both industrialized and developing countries. Natural substances are of great interest in preventative medicine, especially in the field of metabolic syndromes-from insulin resistance to obesity and diabetes. In the present study, we investigated the effect of A. pullulans SM-2001 Extract (Polycan®) on the adipocyte differentiation of 3T3-L1 preadipocytes and the anti-obesity effect of 3T3-L1 adipocytes. Although β-glucan has been found to have health benefits in the regulation of the immune system and blood cholesterol levels, its role in obesity has not been fully investigated. Polycan® suppressed lipid accumulation and glycerol-3-phosphate dehydrogenase (GPDH) activity without affecting cell viability in 3T3-L1 preadipocytes and adipocytes. Polycan® also inhibited cellular lipid accumulation through down-regulation of transcription factors, such as PPARγ and C/EBPα, and induced dose-dependent phosphorylation of AMP-activated protein kinase (AMPK)-a cellular energy sensor-while the total AMPK protein content remained unchanged. Taken together, this shows that the activation of AMPK by Polycan® in adipocytes plays a critical role in Polycan®-induced inhibition of adipocyte differentiation. Our results show that Polycan® has an anti-obesity action in vitro, suggesting a potential novel preventative agent for obesity and other metabolic diseases.

Human Amniotic Fluid Induces Spontaneous Hardening of the Zona Pellucida of Mouse Immature Oocytes During Maturation In Vitro (인간양수에 의한 생쥐 난자 투명대의 정자수용능력 억제의 관찰)

  • Park, Kee-Sang;Lee, Taek-Hoo;Song, Hai-Bum;Chun, Sang-Sik
    • Clinical and Experimental Reproductive Medicine
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    • v.27 no.1
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    • pp.23-29
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    • 2000
  • Objective: Zona pellucida (ZP) has been thought to be the barrier of egg to sperm penetration before and after fertilization. The phenomenon of ZP hardening has been considered as a post-fertilization event until now, and it is generally accepted that it is caused by the secretory products of cortical granules released during the cortical reaction. Hardening of ZP could occur "spontaneously" in mammalian oocytes in standard culture conditions, and that it is probably not a consequence of cortical reaction. The purpose of our study was to investigate the effect of human amniotic fluid (HAF) on nuclear maturation (NM) and fertilization ability of mouse immature oocytes. Methods: HAF was obtained from patients undergoing amniocentesis at $16{\sim}20$ weeks of gestation. HAF from five to ten patients was centrifuged and the supernatants was pooled. Cumulusenclosed mouse immature oocytes were incubated in the medium containing HAF, and examined to confirm NM and fertilization. Female ICR mice (about 3 weeks old) were stimulated with 7.5 IU PMSG. Immature oocytes were isolated at $48{\sim}52$ hrs post PMSG injection and cultured in TCM-199 supplemented with 20% HAF for 18 hrs. FBS was used as a control for the examination. Matured oocytes (MII) were fertilized with sperms collected from the epididymis of male mice (over 10 weeks old). Fertilization was in conducted T6 medium containing 15 mg/ml BSA, and confirmed at 6 hrs post-insemination. Fertilization rate was assessed in zona-intact or zona-free oocytes (denuded by trypsin). Evaluation of NM and fertilization was carried out by rapid staining method. ZP hardening was evaluated by incubating cumulus cell-free mature oocytes in 0.001% chymotrypsin at $37^{\circ}C$ for 10 min. Results: There was no significant difference between the effects of HAF (86.6%) and FBS (87.7%) supplements on NM of immature oocytes. When maturation medium was supplemented with HAF, total fertilization rates (7%) were significantly lower (p<0.01) than that of FBS (85.1%). In HAF group, fertilization rate was increased (p<0.01) in zona-free oocytes (7% versus 100%). The resistance of mouse oocyte ZP to digestion by chymotrypsin after maturation in vitro was significantly higher (p<0.01) in HAF group (86.7%) than in FBS (6.7%). To culture oocytes in FBS were very effective in preventing ZP hardening. However cultured oocytes in HAF showed high rate of ZP hardening (p<0.01). Conclusions: These results suggest that HAF can be used as a supplement for the NM of mouse immature oocytes in vitro. However, HAF induces spontaneous hardening of ZP of mouse immaure oocytes during maturation in vitro.

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Pink Pigmented Facultative Methylotrophic Bacteria(PPFMs): Introduction to Current Concepts (분홍색 색소를 형성하는 methylotrophic acteria(PPFMs): 최근 경향소개)

  • Munusamy, Madhaiyan;Sa, Tongmin;Kim, Jai-Joung
    • Korean Journal of Soil Science and Fertilizer
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    • v.37 no.4
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    • pp.266-287
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    • 2004
  • The non infecting, plant associated bacteria have attracted increased attention for stimulating plant growth and as environmental friendly plant protecting agents. Pink-pigmented facultatively methylotrophic bacteria (PPFMs), classified as Methylobacterium spp., are persistent colonizers of plant leaf surfaces. As the leaves of most or all plants harbor PPFMs that utilize leaf methanol as their sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. Although they are not well known, these bacteria are co-evolved, interacting partners in plant metabolism. This claim is supported, for example, by the following observations: (1) PPFMs are seed-transmitted, (2) PPFMs are frequently found in putatively axenic cell cultures, (3) Low numbers of seed-borne PPFMs correlate with low germinability, (4) Plants with reduced numbers of PPFM show elevated shoot/root ratios, (5) Foliar application of PPFMs to soybean during pod fill enhances seed set and yield, (6) Liverwort tissue in culture requires PPFM-produced vitamin B12 for growth, (7) treated plants to suppress or decrease disease incidence of sheath blight caused by Rhizoctonia solani in rice, and (8) the PPFM inoculation induced number of stomata, chlorophyll concentration and malic acid content, they led to increased photosynthetic activity. Methylobacterium spp. are bacterial symbionts of plants, shown previously to participate in plant metabolism by consuming plant waste products and producing metabolites useful to the plant. There are reports that inform about the beneficial interactions between this group of bacteria and plants. Screening of such kind of bacteria having immense plant growth promoting activities like nitrogen fixation, phytohormone production, alleviating water stress to the plants can be successfully isolated and characterized and integration of such kind of organism in crop production will lead to increased productivity.

Glutamine Deprivation Inhibits Invasion of Human Prostate Carcinoma LnCap Cells through Inactivation of Matrix Metalloproteinases and Modulation of Tight Junctions (글루타민 결핍에 따른 Tight Junction 및 MMPs 활성 조절을 통한 전립선 암세포의 침윤 억제 현상)

  • Shin, Dong Yeok;Choi, Yung Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.8
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    • pp.1167-1174
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    • 2013
  • Cancer cells exhibit increased demand for glutamine-derived carbons to support anabolic processes. Indeed, the spectrum of glutamine-dependent tumors and the mechanisms through which glutamine supports cancer metabolism remain areas of active investigation. In the present study, we investigated the effects of glutamine deprivation on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in human prostate carcinoma LnCap cells. Glutamine deprivation markedly inhibited cell motility and invasiveness in a time-dependent manner. The anti-invasive activity of glutamine deprivation was associated with an increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance (TER). The activities of matrix metalloproteinase (MMP)-2 and MMP-9 were inhibited in a time-dependent fashion by glutamine deprivation, which was correlated with a decrease in expression of their mRNA and proteins and up-regulation of tissue inhibitors of metalloproteinases (TIMPs) expression. Furthermore, glutamine deprivation repressed the levels of the claudin family members, which are major components of TJs that play a key role in the control and selectivity of paracellular transport. Moreover, the levels of E-cadherin, a type I transmembrane glycoprotein, and snail, an epithelial to mesenchymal transition regulator and zinc finger transcription factor, were markedly modulated by glutamine deprivation. Taken together, these findings suggest that TJs and MMPs are critical targets of glutamine deprivation-induced anti-invasion in human prostate carcinoma LnCap cells.

Probiotic Characterization of Acid- and Bile-tolerant Lactobacillus salivarius subsp. salivarius from Korean Faeces

  • Bae, H.C.;Nam, M.S.;Lee, J.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.12
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    • pp.1798-1807
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    • 2002
  • This study was conducted to investigate lactobacillus salivarius subsp. salivarius having probiotic properties to be used as the health adjuncts with fermented milk products. Acid- and bile-tolerant lactobacillus salivarius subsp. salivarius was isolated with lactobacilli MRS broth from faeces of 80 healthy persons (infants, children and adults). It was used as a probiotic strain in fermented milk products. The pH of fermented milk decreased from pH 6.7 to 5.0 and titratable acidity increased from 0.3% to 1.0% by L. salivarius subsp. salivarius (isolation strain 20, 35, and 37), when incubated for 36 h at 37$^{\circ}C$. The number of viable cell counts of fermented milk was maximized at this incubation condition. The SDS-PAGE evidenced no significant change of casein but distinct changes of whey protein were observed by isolated L. salivarius subsp. salivarius for titratable acidity being incubated by 0.9-1.0% at 37$^{\circ}C$. All of the strains produced 83.43 to 131.96 mM of lactic acid and 5.39 to 26.85 mM of isobutyric acid in fermented products. The in vitro culture experiment was performed to evaluate ability to reduce cholesterol levels and antimicrobial activity in the growth medium. The selected L. salivarius subsp. salivarius reduced 23-38% of cholesterol content in lactobacilli MRS broth during bacterial growth for 24 h at 37$^{\circ}C$. All of the isolated L. salivarius subsp. salivarius had an excellent antibacterial activity with 15-25 mm of inhibition zone to E. coli KCTC1039, S. enteritidis KCCM3313, S. typhimurium M-15, and S. typhimurium KCCM40253 when its pH had not been adjusted. Also, all of the isolated L. salivarius subsp. salivarius had partial inhibition zone to E. coli KCTC1039, E. coli KCTC0115 and S. enteritidis KCCM3313 when it had been adjusted to pH 5.7. The selected strains were determined to have resistances of twelve antibiotic. Strains 27 and 35 among the L. salivarius subsp. salivarius showed the highest resistance to the antibiotics. These results indicated that some of the L. salivarius subsp. salivarius (strain 27 and 35) are considered as effective probiotic strains with a potential for industrial applications, but the further study is needed to establish their use as probiotics in vivo.

Vane Shear Test on Nakdong River Sand (베인 전단시험기를 이용한 낙동강모래의 마찰각에 관한 연구)

  • Park, Sung-Sik;Zhou, An;Kim, Dong-Rak
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.3
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    • pp.463-470
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    • 2016
  • A vane shear test (VST) is a simple testing method for determining an undrained shear strength of cohesive soils by minimizing soil disturbance. In this study, the VST was used to determine a shear strength of sand. Dry Nakdong River sand was prepared for loose and dense conditions in a cell and then pressurized with 25, 50, 75 or 100 kPa from the surface of sand. A vane (5 cm in diameter and 10 cm in height) was rotated and a torque was measured within sand. When a torque moment by vane and friction resistance moment by sand is assumed to be equalized, a friction angle can be obtained. When a vane rotates within clay, a uniform undrained shear strength is assumed to be acting on cylindrical failure surface. On the other hand, when it is applied for sand, the failure shape can be assumed to be an octagonal or square column. The relationship between measured torque and resistant force along assumed failure shapes due to friction of sand was derived and the internal friction angle of sand was determined for loose and dense conditions. For the same soil condition, a series of direct shear test was carried out and compared with VST result. The friction angle from VST was between 24-42 degrees for loose sand and 33-53 degrees for dense sand. This is similar to those of direct shear tests.

Study on inhibition effects on metastasis and recurrence of Traditional Herb Medicine(THM) (한약의 전이재발억제 효과에 관한 연구)

  • Lee, Sang-Seob;Yoo, Hwa-Seung;Cho, Jung-Hyo;Son, Chang-Kyu;Lee, Yeon-Weol;Cho, Chong-Kwan
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.9 no.1
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    • pp.75-87
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    • 2003
  • Recently, the occurrence and death rates of cancer have increased rapidly. Metastasis and recurrence is the most important factor of death from cancer. So inhibition of recurrence and metastasis can increase the cure rate of cancer disease. At the basic chinese traditional medicine(TCM), there are a lot of theory related to neoplasm treatment. The metastasis and recurrence of neoplasm was the basis of yudu(餘毒) on remained neoplasm cell and stagnation of blood, thermotoxo, phlegm, asthenia of healthy enerngy and stagnation of vital energy. The principles therapy of neoplasm on metastasis and recurrence was based on knowledge of the method of support the healthy energy and strengthen the body resistance, promote blood circulation to remove blood stasis, clear away heat and toxic materials, dissipate phlegm and disperse the accumulation of evils. But the major clinical features of neoplasm was to be considered in developing a treatment plan include (1) distinguish between clinical and pathologic staging - acute and chronic, (2) classification of pathologic pattern, and (3) distingction of body situation : for examples asthenia - sthenia etc. It was most important to distinguish between supporting the healthy and eliminating the evil factors and to treat differently at the root and the branch cause of a neoplasm. This paper's results indicate that identification and effective use of THM can inhibite netastasis and recurrence and then it will help increasing survival rate. Also as BioTechnology(BT) has developed rapidly nowadays, as genes related to cancer have revealed. So it will give rise to the development of searching the mechanism of herb medicines which have inhibition effects of metastasis and recurrence.

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