• Title/Summary/Keyword: Rb2

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The Comparison of Radiactive Elements $Li^+,Rb^+,Cs^+$Effect on the Growth Circadian Rhythm in Neurospora crassa (방사선 물질 $Li^+,Rb^+,Cs^+$이 Neurospora crassa의 성장 일주기에 미치는 영향)

  • 한상진
    • Environmental Analysis Health and Toxicology
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    • v.8 no.1_2
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    • pp.11-17
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    • 1993
  • Radioactive elements Li/sup +/, Rb/sup +/and Cs/sup +/ effect the period shortening in proportion to the higher concentration on the growth of Neurospora crassa. 1 mM LiCl presented the result of the period length 0.52 h shorter than average circadian rhythm 21.66 h. 1 mM RbCl reduced the period length 1.13 h than control period 21.89 h and 1 mM CsCl reduced 2.12 h than control period 21.89 h. In the equal concentration Cs/sup +/ had an extreme effect. Fatal doses of Li/sup +/, Rb/sup +/ and Cs/sup +/ are 20mM, 30mM and 20mM. In the fatal concentration Neurospora didn't develop more after 7 days and the formation of spores were not given in regular order. Circadian length of Neurospora decreased generally at the last cycle of the growth.

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Effect of Ascorbic Acid and Cysteine for Quality Characteristics of Rice Bread (Ascorbic acid 및 Cysteine이 쌀 식빵의 품질에 미치는 영향)

  • Kim Seon-Jae;Kim Du-Woon
    • Food Science and Preservation
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    • v.13 no.4
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    • pp.450-456
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    • 2006
  • The favorable effect of ascorbic acid and cysteine on the improvement of rice bread quality was investigated by creating and comparing 6 experimental rice breads(RB-1 to RB-6). The RB-3 showed a relatively higher loaf volume, specific loaf volume and bread yield than the other breads. Crust and crumb color of breads were measured using a Hunter celery meter. The RB 5 and RB 6 showed the higher cut L-value than the other broads. As the proportion of the rice in the experimental breads increased, both the crust L-value and the crumb L-value showed higher values. According to the texture profile analysis, the hardness of the RB-1 to RB-3 were lower than those of the other breads. The springness of the experimental broads increased as the percentage of the rice in the breads increases. However, less proportions of rice to breads provided significantly lower level of the chewiness. The cohesiveness did not show any specific pattern by the proportion of rice to breads. The degree of retrogradation of the breads was accelerated when the breads contained more rice or when the breads had neither ascorbic acid nor cysteine. Therefore, RB 3, which contained ascorbic acid and cysteine and less rice, showed the highest retardation in the degree of retrogradation. In addition, the RB 3 showed the highest overall acceptance scores by sensory evaluation.

Overexpression of Rb and E2F-1 in Ataxia-Telangiectasia Lymphocytes

  • Varghese, Susan;Jung, Mi-Ra
    • Archives of Pharmacal Research
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    • v.21 no.6
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    • pp.640-644
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    • 1998
  • AT cells exhibit defective cell cycle regulation following DNA damage. Previous studies have shown that induction of p53 and p2i proteins are delayed in response to ionizing rad iation, resulting in the failure of G1/S checkpoint in AT cells. In this study, further investigation of the molecular mechanisms underlying G1/S phase progression in AT cells was conducted. Exponentially growing normal and AT cells were exposed to 2 Gly of ionizing radiation and the expression levels and functional activities of Rb and E2F-1 proteins were determined. We observed overexpression of hyperphosphorylated Rb and E2F-1 proteins in AT cells, which was unaffected post-irradiation. Furthermore, gel shift assays showed that E2F-1-DNA binding was constitutive in AT cells, whereas it was inhibited in control cells following exposure to ionizing radiation. The data suggests that abnormalities in the function of Rb and E2F-1 proteins may also be responsible for the failure of AT cells to arrest in the G1/S checkpoint in response to DNA damage.

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Anti-apoptotic Activity of Ginsenoside Rb1 in Hydrogen Peroxide-treated Chondrocytes: Stabilization of Mitochondria and the Inhibition of Caspase-3

  • Na, Ji-Young;Kim, Sok-Ho;Song, Ki-Bbeum;Lim, Kyu-Hee;Shin, Gee-Wook;Kim, Jong-Hoon;Kim, Bum-Seok;Kwon, Young-Bae;Kwon, Jung-Kee
    • Journal of Ginseng Research
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    • v.36 no.3
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    • pp.242-247
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    • 2012
  • Chondrocyte apoptosis has been recognized as an important factor in the pathogenesis of osteoarthritis (OA). Hydrogen peroxide ($H_2O_2$), which produces reactive oxygen species, reportedly induces apoptosis in chondrocytes. The ginsenoside $Rb_1$ (G-$Rb_1$) is the principal component in ginseng and has been shown to have a variety of biological activities, such as anti-arthritis, anti-inflammation, and anti-tumor activities. In this study, we evaluated the effects of G-$Rb_1$ on the mitochondrial permeability transition (MPT) and caspase-3 activity of chondrocyte apoptosis induced by $H_2O_2$. Cultured rat articular chondrocytes were exposed to $H_2O_2$ with or without G-$Rb_1$ and assessed for viability, MPT, Bcl-xL/Bax expression, caspase-3 activity, and apoptosis. The co-treatment with G-$Rb_1$ showed an inhibition of MPT, caspase-3 activity, and cell death. Additionally, the levels of the apoptotic protein Bax were significantly lower and the levels of the anti-apoptotic protein Bcl-xL were higher compared with $H_2O_2$ treatment alone. The results of this study demonstrate that G-$Rb_1$ protects chondrocytes against $H_2O_2$-induced apoptosis, at least in part via the inhibition of MPT and caspase-3 activity. These results demonstrate that G-$Rb_1$ is a potentially useful drug for the treatment of OA patients.

Expression of Cell Cycle Related Genes in HL60 Cells Undergoing Apoptosis by X-irradiation (HL60 세포주에서 방사선 조사에 의한 Apoptosis와 세포 주기 관련 유전자의 발현 변화)

  • Kim, Jin-Hee;Park, In-Kyu
    • Radiation Oncology Journal
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    • v.16 no.4
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    • pp.377-388
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    • 1998
  • Purpose : To evaluate changes in expression of cell cycle related genes during apoptosis induced in HL60 cells by X-irradiation to understand molecular biologic aspects in mechanism of radiation therapy. Material and Methods : HL-60 cell line (promyelocytic leukemia cell line) was grown in culture media and irradiated with 8 Gr by linear accelerator (6 MV X-ray). At various times after irradiation, ranging from 3 to 48 hours were analyzed apoptotic DNA fragmentation assay for apoptosis and by western blot analysis and semi-quantitative RT-PCR for expression of cell cycle related genes (cyclin A, cyclin B, cyclin C, cyclin Dl, cyclin E, cdc2, CDK2, CDK4, $p16^{INK4a}$, $p21^{WAF1}$, $p27^{KIP1}$, E2F, PCNA and Rb). Results : X-irradiation (8 Gy) induced apoptosis in HL-60 cell line. Cycline A protein increased after reaching its peak 48 h after radiation delivery and cyclin E, E2F, CDK2 and RB protein increased then decreased after radiation. Radiation induced up-regulation of the expression of E2F is due to mostly increase of Phosphorylated retinoblastoma proteins (ppRb). Cyclin Dl, PCNA, CDC2, CDK4 and $p16^{INK4a}$ protein underwent no significant change at any times after irradiation. There was not detected $p21^{WAF1}$ and $p27^{KIP1}$ protein. Cyclin A, B, C mRNA decreased immediately after radiation and then increased at 12 h after radiation. Cyclin Dl mRNA increased immediately and then decreased at 48 h after radiation. After radiation, cyclin E mRNA decreased with the lapse of time. CDK2 mRNA decreased at 3h and increased at eh after radiation. CDK4 mRNA rapidly increased at 6 to 12 h after radiation. There was no change of expression of $p16^{INK4a}$ and not detected in expressin of $p21^{WAF1}$ and $p27^{KIP1}$ mRNA. Conclusion : We suggest that entry into S phase may contribute to apoptosis of HL60 cells induced by irradiation. Increase of ppRb and decrease of pRb protein are related with radiation induced auoptosis of HL60 cells and tosis of HL60 cells induced by irradiation. Increase of ppRb and decrease of PRb protein are related with radiation induced apoptosis of HL60 cells and this may be associated with induction of E2F and cyclinE/CDK2. These results support that $p21^{WAF1}$ and $p27^{KIP1}$ are not related with radiation induced-apoptosis.

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Regulation of Wnt/β-catenin Signal Transduction in HT-29 Colon Cancer Cells by a Rhododendron brachycarpum Fraction (홍만병초 분획물에 의한 HT-29대장암 세포의 Wnt/β-catenin 신호전달 조절)

  • Sim, Bo Ram;Nam, Young Sun;Lee, Ja Bok
    • Journal of Life Science
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    • v.29 no.8
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    • pp.871-878
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    • 2019
  • The aim of this study was to determine the anticancer activities of an 80% methanol extract and various fractions of Rhododendron brachycarpum (RB). The n-hexane fraction of RB showed the highest inhibitory activity (Inhibit concentration $50%=20.2{\pm}1.2{\mu}g/ml$) in HT-29 cells. Colony- and sphereforming abilities were significantly correlated with a decrease in the cell count and size. A TOP/FOP flash reporter assay revealed that the inhibitory activity of the n-hexane fraction of RB ($0.22{\pm}0.02$ fold change) was lower than that of the 80% methanol extract and that of other fractions. The n-hexane and ethyl acetate fractions of RB were predominantly dependent on the expression levels of intracellular ${\beta}-catenin$. Western blotting using $p-GSK3{\beta}$ with only the n-hexane fraction of RB was conducted to examine whether these secondary metabolites reduced ${\beta}-catenin$ degradation. Intracellular ${\beta}-catenin$ regulation resulted in quantitative changes in the nucleus. In summary, these results demonstrate the potential of the n-hexane fraction of RB as a natural anticancer agent.

MDM2, p53 and pRb Expression Prior to Definitive Chemoradiotherapy in Esophageal Carcinoma (식도암에서 MDM2, p53, pRb 발현과 동시적 항암화학방사선요법의 결과)

  • Yoon, Mee-Sun;Lee, Jae-Hyuk;Cho, Sang-Hee;Song, Ju-Young;Ahn, Sung-Ja;Chung, Ik-Joo;Chung, Woong-Ki;Nah, Byung-Sik;Nam, Taek-Keun
    • Radiation Oncology Journal
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    • v.25 no.4
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    • pp.193-200
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    • 2007
  • Purpose: This study evaluated the pretreatment expression patterns of MDM2, p53, and pRb proteins to determine if the expression patterns could predict the outcome of concurrent chemoradiotherapy (CCRT) for esophageal squamous cell carcinoma and aid in the decisions for the selection of treatment modalities. Materials and Methods: Fifty-one patients that were treated with definitive chemoradiotherapy for stage $I{\sim}IVa$ esophageal squamous cell carcinoma were selected for this study. Radiotherapy was administered with daily $1.8{\sim}2\;Gy$ fractions up to a median dose of 54 Gy for primary tumors, and with four cycles of cisplatin/5-fluorouracil chemotherapy that was administered every 4 weeks, the first two cycles of which were administered concurrently with radiotherapy. Expression of MDM2, p53, and pRb was investigated by immunohistochemical analysis using pretreatment biopsy specimens. Results: MDM2, p53, and pRb were detected with high immunoreactivity in 19.6%, 27.5%, and 66.7% of the patients, respectively. However, there was no significant correlation between expression of these factors and clinical outcome. By the use of multivariate analysis with nine covariates-age, tumor location, tumor length, stage, pathological response, clinical response, MDM2 expression, p53 expression, and pRb expression, only pathological response and stage were significant factors for cause-specific survival. Conclusion: Expression of MDM2, p53, and pRb was not found to be clinically significant for predicting outcomes after CCRT in this study. Further studies with a larger patient population and longer follow-up periods are needed to re-evaluate the expression pattern and to identify new predictors for CCRT response.

Ginsenosides Inhibit Endothelium - dependent Contraction in the Spontaneously Hypertensive Rat Aorta isn vitro (선천성 고혈압 랫드에서 ginsenosides에 의한 내피의존성수축의 억제작용)

  • 김낙두;최원선
    • Journal of Ginseng Research
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    • v.21 no.2
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    • pp.125-132
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    • 1997
  • Our previous study showed that in vivo treatment of spontaneously hypertensive rats (SHR) with protopanaxatriol ginsenosides (PPT) reduces the blood pressure and inhibits the con- tractions induced by endothelium-derived contracting factor (prostaglandin endoperoxide ($PGH_2$) and superoxide anion) in aorta isolated from SHR. The aim of the present study is to examine whether PPT improves endothelial functions in the isolated thoracic aorta of SHR in vitro. Treatments of aortic rings with PPT, purified ginsenoside $Rg_1$ ($Rg_1$) or indomethacin normalized endotheliuln-dependent relaxation to acetylcholine, but not with protopanaxadiol ginsenosides (PPD) and purified ginsenoside Rb1 (Rb1). The effects of PPT were dose-dependent. PGH,- and oxygen free radical-inducted contractions in rat aorta without endothelium were inhibited by PPT or $Rg_1$, but not by PPD or $Rb_1$. Contractions induced by PGF2$\alpha$, U-46619, a stable thromboxane A2 agonist or KCI (60 mM) were not inhibited by PPT, $Rg_1$ or $Rb_1$. These findings demonstrate that PPT but not PPD scavenges the oxygen-derived free radicals and/or antagonize the effects of $PGH_2$ in the vascular smooth muscle and may explain the hypotensive effect of ginseng in the SHR.

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Component analysis of cultivated ginseng, cultivated wild ginseng, and wild ginseng and the change of ginsenoside components in the process of red ginseng (인삼.산양삼.자연산 산삼의 ginsenoside 함량 분석 및 홍삼화 후의 변화 관찰)

  • Jeong, H.S.;Lim, C.S.;Cha, B.C.;Choi, S.H.;Kwon, K.R.
    • Journal of Pharmacopuncture
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    • v.13 no.1
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    • pp.63-77
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    • 2010
  • Objectives: The aim of this experiment is to provide an objective differentiation of cultivated ginseng, cultivated wild ginseng, and wild ginseng through component analysis, and to know the change of ginsenoside components in the process for making red ginseng. Methods: Comparative analysis of ginsenoside $Rb_1,\;Rb_2$, Rc, Rd, Re, Rf, $Rg_1,\;Rg_3,\;Rh_1$ and $Rh_2$ from the cultivated ginseng 4 and 6 years, cultivated wild ginseng, and wild ginseng were conducted using High Performance Liquid Chromatography(hereafter HPLC). And the same analyses were conducted in the process of red ginseng. Results: 1. For content comparison of ginsenoside $Rb_1$, Rc, Rd, Rf, $Rg_1$ and $Rh_1$, wild ginseng showed high content, followed cultivated ginseng 4 and 6 years, cultivated wild ginseng showed low content than any other samples. 2. For content comparison of ginsenoside $Rb_2$ and Re, cultivated ginseng 4 years showed high content, followed wild ginseng and cultivated ginseng 6 years, cultivated wild ginseng showed low content than any other samples. 3. For content comparison of ginsenoside $Rg_3$, wild ginseng and cultivated wild ginseng were only showed low content. 4. For content comparison of ginsenoside $Rh_2$, cultivated wild ginseng was only showed low content. 5. In the process of red ginseng, ginsenoside $Rb_1,\;Rb_2$, Rc, Rd, $Rg_3$ and $Rh_1$ were increased, and ginsenoside Re and $Rg_1$ were decreased in cultivated wild ginseng. 6. In the process of red ginseng, ginsenoside $Rg_3$ and $Rh_1$ were increased, and ginsenoside $Rb_2$, Rc, and Re were decreased in cultivated ginseng 4 years. 7. In the process of red ginseng, ginsenoside $Rb_1,\;Rb_2$, Rf and $Rh_1$ were increased, and ginsenoside Rc and Rd were decreased in cultivated ginseng 6 years. Conclusions: Distribution of ginsenoside contents to the cultivated ginseng, cultivated wild ginseng, and wild ginseng was similar and was not showed special characteristics between samples. And the change of ginsenoside to the process of red ginseng, cultivated ginseng and cultivated wild ginseng were showed different aspect.

Human Safety of rbST Contained in Milk (우유중 함유된 rbST의 인체에 대한 안전성)

  • 송지용
    • Proceedings of the Korean Society of Food Hygiene and Safety Conference
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    • 1994.12a
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    • pp.15-26
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    • 1994
  • Bovine somatotropin(bST) or bovine growth hormone (bGH) is a protein of 191 amino acids produced by the anterior pituitary gland of cattle. Recombinant bovine somatotropin(rbST) is biosynthetic versions of the naturally occurring pituitary hormone in cows. The use of rbST in dairy cows promises to improve the efficiency of milk production around the world. Using recombinant DNA technology, bST can now be produced in commercial quantities. The recombinant bST(rbST) is biologically identical to the found in the bovine pituitary. Milk from rbST-treated cows has been found to have the same nutritional value and composition as milk from untreated cows. In November of 1993, rbST finally was approved by the FDA, nearly 10 years after filing a licence applica-tion. rbST has been one of the most extensively studied animal drug products to be reviewed by the agency. Three scientific facts will help to reassure the public about the safety of the milk suppy.: 1. rbST has no biological activity in humans when indigested orally or when given by intramuscular injection. 2. Insulin-like growth factor 1(IGF-1) is not orally active. Any changes in IGF-1 levels in milk are well within normal variation and are lower than those reported in human milk. 3. All cow's milk contains bST, and no significant change in bST levels in milk occurs as a result of giving cows supplemental bST. Based on the scientific evidence, the public can be confident that milk and meat from rbST-treated cows is safe to consumers.

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