• 제목/요약/키워드: pH dependent

검색결과 1,766건 처리시간 0.036초

Glucose Deprivation and Immunostimulation Induced Death in Rat Primary Astrocytes is Mediated by Their Synergistic Effect on the Decrease in Cellular ATP Level

  • Choi, Ji-Woong;Yoo, Byoung-Kwon;Yoon, Seo-Young;Jeon, Mi-Jin;Ko, Kwang-Ho
    • Biomolecules & Therapeutics
    • /
    • 제12권1호
    • /
    • pp.25-33
    • /
    • 2004
  • In this study we investigated whether ATP loss was involved in the potentiated death of immunostimulated rat primary astrocytes in glucose-deprived condition. Rat primary astrocytes immunostimulated with LPS plus IFN-${\gamma}$ for 48 h underwent death upon glucose deprivation, which dependent on the production of peroxynitrite. Intracellular ATP level synergistically decreased by glucose deprivation in immunostimulated astrocytes but not in control cells, and the loss of ATP occurred well ahead of the LDH release. The synergistic cell death and ATP loss by immunostimulation and glucose deprivation were inhibited by iNOS inhibitor (L-NAME and L-NNA) or peroxynitrite decomposition catalyst (also a superoxide anion scavenger), Mn(III)tetrakis(N-methyl-4'-pyridyl)porphyrin (MnTMPyP). Exogenous addition of peroxynitrite generator, SIN-l timedependently induced ATP loss and cell death in the glucose-deprived astrocytes. Depletion of intracellular glutathione (GSH) and dis겨ption of mitochondrial transmembrane potential (MTP) were also observed under same conditions. Supply cellular ATP by the addition of exogenous adenosine or ATP during glucose deprivation inhibited ATP depletion, GSH depletion, MTP disruption and cell death in SIN-l treated or immunostimulated astrocytes. This study showed that perturbation in the regulation of intracellular ATP level in immunostimulated astrocytes might make them more vulnerable to energy challenging stimuli.

한방생약재를 이용한 약선차의 항산화 및 항암효과 (Antioxidant and Anticancer Activities of Yak-Sun Tea Prepared by Oriental Medicinal Herbs)

  • 최일숙;차은정;이연리;김재근
    • 한국식품영양학회지
    • /
    • 제25권3호
    • /
    • pp.447-453
    • /
    • 2012
  • Various types of tea are consumed as a popular beverage worldwide particularly in Asian countries such as Korea, China, and Japan. The purpose of this study was to investigate the mineral contents, antioxidant properties and anticancer activity of Yak-Sun tea that is prepared by six oriental medicinal herbs. The results of the mineral contents were as follows; Ca, Mg, and Na contents were higher than those of green tea, whereas Fe, P, and K contents were lower than those of green tea. The total phenolics and flavonoid content of the Yak-Sun tea were higher than those of green and black teas. The $IC_{50}$ values of DPPH radical, hydroxyl radical, hydrogen peroxide radical scavenging of Yak-Sun tea were 0.78, 1.58, and 2.04 $mg/m{\ell}$, respectively, whereas the radical scavenging values of ${\alpha}$-tocopherol was 0.06, 0.05, and 0.09 $mg/m{\ell}$, respectively. When cancer cells were treated with Yak-Sun tea, the anticancer activity increased in a dose dependent manner. HCT116 colon cancer cell lines were dramatically increased, as compared to other cancer cell lines, such as MCF-7, H460, and MKN45 cell lines. The results of this study demonstrated that Yak-Sun tea could function as a tea to enhance health conditions for antioxidant and anticancer activity.

Effects of various receptor antagonists on the peripheral antinociceptive activity of aqueous extracts of Dicranopteris linearis, Melastoma malabathricum and Bauhinia purpurea leaves in mice

  • Zakaria, Zainul Amiruddin;Sodri, Nurul Husna;Hassan, Halmy;Anuar, Khairiyah;Abdullah, Fatimah Corazon
    • 셀메드
    • /
    • 제2권4호
    • /
    • pp.38.1-38.6
    • /
    • 2012
  • The present study aimed to determine the possible mechanisms of the peripheral antinociception of the aqueous extracts of Dicranopteris linearis (AEDL), Melastoma malabathricum (AEMM) and Bauhinia purpurea (AEBP) leaves in mice. Briefly, the antinociceptive profile of each extract (300, 500, and 1000 mg/kg; subcutaneous (s.c.)), was established using the abdominal constriction test. A single dose (500 mg/kg) of each extract (s.c.) was pre-challenged for 10 min with various pain receptors' antagonists or pain mediators' blockers and 30 min later subjected to the antinociceptive assay to determine the possible mechanism(s) involved. Based on the results obtained, all extracts exerted significant (p < 0.05) antinociceptive activity with dose-dependent activity observed only with the AEMM. Furthermore, the antinociception of AEDL was attenuated by naloxone, atropine, yohimbine and theophylline; AEMM was reversed by yohimbine, theophylline, thioperamide, pindolol, reserpine, and 4-chloro-DL-phenylalanine methyl ester hydrochloride; and of AEBP was inhibited by naloxone, haloperidol, yohimbine and reserpine. In conclusion, the antinociceptive activity of those extracts possibly involved the activation of several pain receptors (i.e. opioids, muscarinic, ${\alpha}_2$-adrenergic and adenosine receptors, adenosine, H3-histaminergic and $5HT_{1A}$, dopaminergic receptors).

레토르트 Crab Analog의 살균 최적화 및 품질 특성 (Optimum Sterilization Conditions and Quality Characteristics of the Retort-Sterilized Crab Analog)

  • 윤재웅;오동훈;김병균;안병수;최종덕;오광수
    • 한국수산과학회지
    • /
    • 제44권1호
    • /
    • pp.31-36
    • /
    • 2011
  • This study developed a normal temperature-circulatable retort-sterilized crab analog (RSCA) with a long shelf-life by retort sterilization. We examined the optimum sterilization conditions and quality characteristics of the RSCA. A central composite design for response surface methodology (RSM) was adopted to optimize of the retort sterilization. The central composite design consisted of 11 samples: four factorial points, four star points, and three central points. The sterilization temperature and $F_0$-value for retort sterilization were the independent variables, and the shearing force, whiteness, and sensory score for texture were the dependent variable. The RSM analysis of the multiple response optimization for the RSCA using the Minitap statistical programing gave an $F_0$-value of 3.3 min. at $117.5^{\circ}C$. The RSM analysis also indicated that the sterilization temperature during retort sterilization was the most influential factor, while the $F_0$-value had little effect on the quality of the RSCA. The moisture, pH and volatile basic nitrogen contents of the RSCA product were 73.1%, 7.3 and 17.2 mg/100 g, respectively, and viable cells count was >18 CFU/g. And sensory quality characteristics of this RSCA was similar to those of a commercial crab analog.

Magnetic properties of micro-patterned array of anti-dots in Co/Ni bilayer

  • Deshpande, N.G.;Seo, M.S.;Zheng, H.Y.;Lee, S.J.;Rhee, J.Y.;Kim, K.W.;Lee, Y.P.
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
    • /
    • pp.276-276
    • /
    • 2010
  • Large-area micropatterned array of Co/Ni bilayer anti-dots was fabricated using photolithography and wet etching process. The surface morphology as well as the surface topography was checked by scanning electron microscopy and atomic force microscopy, whereas the magnetic properties were studied by magneto-optical Kerr effect (MOKE) and magnetic force microscopy (MFM). Systematic studies of the magnetic-reversal mechanism, the in-plane anisotropy and the switching field properties were carried out. To get a comprehensive knowledge about the domain configuration, we also employed OOMMF simulations. It was found from the MOKE measurements that a combined effect of configurational and the magneto-crystalline anisotropy simultaneously works in such micropatterned bilayer structures. In addition, the inclusion of holes in the uniform magnetic film drastically affected the switching field. The MFM images show well-defined domain structures which are periodic in nature. The micromagnetic simulations indicate that the magnetization reversal of such a structure proceeds by formation and annihilation of domain walls, which were equally manifested by the field-dependent MFM images. The observed changes in the magnetic properties are strongly related to both the patterning that hinders the domain-wall motion and to the magneto-anisotropic bilayered structure.

  • PDF

Methanol 자화세균에 관한 생물학적 연구 (A Biological Study on the Methanol-Utilizing Bacteria)

  • 이영녹;배광성;박정호
    • 미생물학회지
    • /
    • 제16권4호
    • /
    • pp.170-179
    • /
    • 1978
  • By the successive enrichment culture, more than 250 methanol-utilizing bacteria were isolated from various samples such as soil, waste water and sewage. Two strains of which were selected and tentatively identified as Acinetobacter sp. and Pseudomonas sp. experiments were carried out to determine the growth conditions for the higher biomass yield and to demonstrate the difference to protein composition dependent upon carbon sources of these two species. the results were as follows ; 1. the optimum pH was determined as 8 in the both species. The optimum temperature in Acinetobacter sp. was $25^{\circ}C{\sim}30^{\circ}C$ and pseudomonas sp. was $30^{\circ}C-35^{\circ}C$. The optimum initial concentration of mthanol was determined as 1-2% in Acinetobacter sp. and 2-3% in pseudomonas sp. 2. The optimum concnetrations of nitrogen source, micro-elements, and vitamins such as biotin and thiamine-HCl in Acnetobactar sp. were 1g $(NH_4)_3SO4,\;1{\sim}3mg\;Mn^{++},\;4mg\;Fe^{++},\;10{\mu}g\;biotin,\;and\;100{\mu}g$ thiamine-HCl per liter medium. In the Pseudomonas sp., 2g $(NH_4)_3SO4,\;1mg\;Mn^{++},\;trace\;amounts\;of\;Fe^{++},\;5{\mu}g\;biotin,\;and\;100{\mu}g$ thiamine HCl per liter were effective. Maximum biomass yield was 2.5g/l in Acinetobacter sp. and 4.8g/l in Pseudomonas sp. 3. Protein composition of the two strains exhibited that alkai-labile protein was higher than alkali-stable protein. In Pseudomonas sp., the contents of acid soluble fraction and alkali-stable protein of the cells grown in the methanol medium were higher than in sucrose medium. On the other hand, in Acinetobacter sp., alkalilabile protein of the cells grown in sucrose medium was higher than in methanol medium.

  • PDF

Fermentation-Mediated Enhancement of Ginseng's Anti-Allergic Activity against IgE-Mediated Passive Cutaneous Anaphylaxis In Vivo and In Vitro

  • Hwang, Seon-Weon;Sun, Xiao;Han, Jun-Hyuk;Kim, Tae-Yeon;Koppula, Sushruta;Kang, Tae-Bong;Hwang, Jae-Kwan;Lee, Kwang-Ho
    • Journal of Microbiology and Biotechnology
    • /
    • 제28권10호
    • /
    • pp.1626-1634
    • /
    • 2018
  • Ginseng (the root of Panax ginseng Meyer) fermented by Lactobacillus plantarum has been found to attenuate allergic responses in in vitro and in vivo experimental models. Ginseng has been reported to also possess various biological functions including anti-inflammatory activity. The present study was aimed at comparing the anti-allergic effect of ginseng and fermented ginseng extracts on IgE-mediated passive cutaneous anaphylaxis in vitro in a murine cell line and in vivo in mice. Fermented ginseng extract (FPG) showed higher inhibitory effect against in vitro and in vivo allergic responses when compared with ginseng extract (PG). The secretion of ${\beta}$-hexosaminidase and interleukin (IL)-4 from the IgE-DNP-stimulated RBH-2H3 mast cells were significantly (p < 0.05) inhibited by FPG treatment, and this effect was concentration-dependent. Further, MKK4 activation and subsequent JNK phosphorylation were attenuated by FPG treatment. The inhibitory effect of FPG on the in vitro allergic response was verified in vivo against IgE-DNP-induced passive cutaneous anaphylaxis in a mouse model. These data indicated that the fermentation of ginseng with L. plantarum enhanced its anti-allergic effects both in vitro and in vivo. We predict that compositional changes in the ginsenosides caused by the fermentation may contribute to the change in the anti-allergic effects of ginseng. The results of our study highlight the potential of the use of FPG as a potential anti-allergic agent.

구강암 세포주에서 실망초 추출물의 항암효능 (Anticancer effect of methanol extract of Erigeron bonariensis on oral cancer cells)

  • 장분실;임선아
    • 한국치위생학회지
    • /
    • 제20권5호
    • /
    • pp.763-771
    • /
    • 2020
  • Objectives: Erigeron bonariensis is a type of Erigeron found throughout the tropical and subtropical areas as one of the perennial plants or pioneer plants. It is known to show detoxifying, antipyretic, and anticancer effects for various cancers. However, there are no reports on the anticancer effect of E. bonariensis on oral cancer cells. In the present study, we investigated the effects of the methanol extract of Erigeron bonariensis (MEEB) on the inhibition of cell growth and induction of apoptosis in mucoepidermoid carcinoma (MEC) cell lines, including the MC3 and YD15 oral cancer cells. Methods: MC3 Cells were treated by dimethyl sulfoxide (DMSO) or methanol extracts of 20 various natural products 20 ㎍/mL for 48 hours and cell viability were analyzed as Trypan blue exclusion assay. The effects of MEEB treatment on the cell viability of MC3 and YD15 cells, for 48 h, were analyzed by Trypan blue exclusion assay. The anticancer efficacy and apoptosis of oral cancer cell lines were analyzed by western blot analysis. The statistical significance of differences between groups was analyzed by Student's two-tailed t-test. A value of P<0.05 compared to the vehicle control was considered statistically significant. Results: Among 20 different naturally derived products, MEEB significantly inhibited cell viability and increased cleaved poly [ADP-ribose] polymerase 1 (PARP) protein in the MC3 and YD15 cells in a concentration-dependent manner. Conclusions: These results suggest that MEEB can be used as a natural anticancer drug for the treatment of human oral cancer.

Functional Anaylsis of sprD Gene Encoding Streptomyces griseus Protease D(SGPD) in Streptomyces griseus

  • Choi Si-Sun;Kim Joung-Hoon;Kim Jong-Hee;Kang Dae-Kyung;Kang Sang-Soon;Hong Soon-Kwang
    • Journal of Microbiology and Biotechnology
    • /
    • 제16권2호
    • /
    • pp.312-317
    • /
    • 2006
  • The chromosomal sprD gene encoding Streptomyces griseus protease D (SGPD), a chymotrypsin-like protease, was disrupted in Streptomyces griseus by insertion of the neomysin-resistance gene. The production of chymotrypsin activity of sprD disruptant was not completely abolished, but delayed by 24 h, compared with that of wild-type strain. The aerial mycelial formation of sprD disruptant was retarded, and specifically the formation of spores was not observed in the central region of colonies. However, normal morphological development into spores was observed in the marginal region of colonies. In addition, the production of yellow pigment that might be dependent on A-factor was also decreased in the sprD disruptant, compared with that of the wild-type strain. Introduction of the sprD gene, which was placed on a high copy-numbered plasmid into S. griseus ${\Delta}sprD$, partially restored the ability of morphological development, and a significant level of sporulation was observed. When the overexpression vector for sprD, pWHM3-D, was introduced in S. griseus, there was no significant change in the chymotrypsin activity or colonial morphology, in contrast to Streptomyces lividans, indicating the presence of a tight regulation system for the overexpression of the sprD gene in S. griseus.

Properties of Spontaneous Activity in Gastric Smooth Muscle

  • Suzuki, H.;Yamamoto, Y.;Hirst, G.D.S.
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제3권2호
    • /
    • pp.119-125
    • /
    • 1999
  • Mammalian gastric smooth muscles generate spontaneous rhythmic contractions which are associated with slow oscillatory potentials (slow waves) and spike potentials. Spike potentials are blocked by organic $Ca^{2+}-antagonists,$ indicating that these result from the activation of L-type $Ca^{2+}-channel.$ However, the cellular mechanisms underlying the generation of slow wave remain unclear. Slow waves are insensitive to $Ca^{2+}-antagonists$ but are blocked by metabolic inhibitors or low temperature. Recently it has been suggested that Interstitial Cells of Cajal (ICC) serve as pacemaker cells and a slow wave reflects the coordinated behavior of both ICC and smooth muscle cells. Small segments of circular smooth muscle isolated from antrum of the guinea-pig stomach generated two types of electrical events; irregular small amplitude (1 to 7 mV) of transient depolarization and larger amplitude (20 to 30 mV) of slow depolarization (regenerative potential). Transient depolarization occurred irregularly and membrane depolarization increased their frequency. Regenerative potentials were generated rhythmically and appeared to result from summed transient depolarizations. Spike potentials, sensitive to nifedipine, were generated on the peaks of regenerative potentials. Depolarization of the membrane evoked regenerative potentials with long latencies (1 to 2 s). These potentials had long partial refractory periods (15 to 20 s). They were inhibited by low concentrations of caffeine, perhaps reflecting either depletion of $Ca^{2+}$ from SR or inhibition of InsP3 receptors, by buffering $Ca^{2+}$ to low levels with BAPTA or by depleting $Ca^{2+}$ from SR with CPA. They persisted in the presence of $Ca^{2+}-sensitive$ $Cl^--channel$ blockers, niflumic acid and DIDS or $Co^{2+},$ a non selective $Ca^{2+}-channel$ blocker. These results suggest that spontaneous activity of gastric smooth muscle results from $Ca^{2+}$ release from SR, followed by activation of $Ca^{2+}-dependent$ ion channels other than $Cl^-$ channels, with the release of $Ca^{2+}$ from SR being triggered by membrane depolarization.

  • PDF