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Uptake of Radionuclides by Some Fungi

  • Mahmoud, Yehia A.G.
    • Mycobiology
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    • v.32 no.3
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    • pp.110-114
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    • 2004
  • Mycobiota including Alternaria alternata, Fusarium verticillioides and Aspergillus pulverulents were tested for their ability to uptake radiocobalt(Co-60) and radiocesium(Cs-137) from radionuclide containing medium. A. alternata was the most efficient fungal species for uptake of radioisotopes, followed by A. pulverulents, whereas F. verticilliodies came in the last rank. The conditions of radioisotope uptake were optimized such as the form of the fungal organism either spores or mycelium, inoculum age and pH of growing medium. Furthermore the total pigments of the tested fungi were extracted and tested for their ability to bind with radioisotope, where melanin of A. alternata produced about 60% for radioisotope uptake out of total added radioisotope radioactivity. Moreover, transmission electron microscopic examination of radioisotope exposed spores showed high precipitation of melanin granules in the spore wall and within the cell as comparing to untreated spores.

EFFECT OF BUTYLATED HYDROXYTOLUENE (BHT) AND ITS METABOLITE ON THE UPTAKE OF TAUROCHOLATE IN PRIMARY CULTURE OF ADULT RAT HEPATOCYTES

  • Dong, Mi-Sook;Choe, Suck-Young;Yang, Kyu-Hwan
    • Toxicological Research
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    • v.5 no.1
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    • pp.9-15
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    • 1989
  • The effect of butylated hydroxytoluene (BHT) and its major metabolite, 3, 5-di-tert-butyl-4-hydroxybenzoic acid (BHT-acid) on the uptake of taurocholate into hepatocytes was studied using the primary culture of rat hepatocytes. Hepatocyte were isolated by an in situ collagenase perfusion technique and maintained as a monolayer in serum-free meadia for 24 hours before use. The uptake of taurocholate was saturable with an apparent Km of 12.8+2.8 MuM and Vmax of 0.18+0.01 nmol/mg/min. Both BHT and BHT-acid inhibited the hepatocellular uptake of taurocholate when they were added to the culture.

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High FDG Uptake in Sclerosing Hemangioma (경화성 혈관종에서의 높은 FDG 섭취)

  • Lee, Jong-Jin;Kang, Won-Jun;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.3
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    • pp.212-213
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    • 2005
  • A 42 years old woman underwent F-18 FDG PET because of the incidentally detected lung mass on chest X-ray. PET/CT showed hypermetabolic lesion in the lung right upper lobe and the lung cancer was suspected because of the high FDG uptake. However, pathologic diagnosis was sclerosing hemangioma. There are few reports on the evaluation of sclerosing hemangioma using FDG PET. A report showed a slightly increased uptake (standardized uptake ratio of 1.8) (1), and another report showed unsatisfactory result (2). We suggest that sclerosing hemangioma could be seen as hypermetabolic lesion on the FDG PET.

Characterization of Putrescine Uptake in Hamster Amelanocytic Melanoma AMEL-3 Cells

  • Garcia-Fernandez, Antonio J.;Rodriguez, Rosa A.;Perez-Pertejo, Yolanda;Balana-Fouce, Rafael
    • Molecules and Cells
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    • v.20 no.1
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    • pp.127-135
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    • 2005
  • The uptake of putrescine, spermidine and spermine by Fortner's hamster amelanocytic melanoma AMEL-3 cells was observed in this study to be time-dependent, temperature-sensitive, pH-dependent and saturable. Metabolic poisons nullified polyamine uptake, an indication that this is an energy-requiring mechanism. The presence of $Na^+$ ions was found to be requisite to full activity. Valinomycin, gramicidin, monensin and the calcium ionophore calcimycin were also observed to inhibit the process substantially. The transporter active site would seem to contain sulfhydryl groups. Other diamines and polyamine analogues, as well as cationic diamidines, suppressed putrescine uptake. The presence of the ornithine decarboxylase inhibitor DFMO in the culture medium induced putrescine inflows. Putrescine, in turn, induced the negative expression of the carrier, thus suggesting that this influx mechanism is governed by up/down regulation. The cationic diamidine CGP 40215A and its analogue CGP039937A competitively inhibited putrescine transport, with Ki values of 1.9 and $15{\mu}M$, respectively. The role of polyamine uptake in these cultures is discussed.

$\alpha$-Glucosidase Inhibition and Glucose-uptake Stimulation by Ethanol Extracts from Edible Mushroom Hinmogi (Tremella fuciformis)

  • Jeong, Hye-Jin;Yoon, Seon-Joo;Pyun, Yu-Ryang
    • Food Science and Biotechnology
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    • v.17 no.2
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    • pp.274-278
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    • 2008
  • Ethanol extracts from the edible mushroom hinmogi (Tremella fuciformis, TF) were used in the investigation of effects on $\alpha$-glucosidase in vitro and on glucose-uptake in 3T3-L1 mature adipocytes. Addition of the extract significantly inhibited $\alpha$-glucosidase from small intestine of porcine and of rat (about 42 and 35% of control, respectively), and stimulated glucose uptake (about 100% of control), of which activity was higher than that of maitake (Grifola frondosa) X-fraction, a well known anti-diabetic substance. When the ethanol extracts were further partitioned successively by organic solvents and purified by silica gel chromatography, the non-polar layer (F-7) from hexane layer showed highest stimulatory activity of glucose-uptake among layers tested. The major components of the F-7 were 1-monooleoylglycerol and 1-monopalmitoylglycerol. Our report is the first description of TF with stimulatory activity of glucose-uptake. These results suggest that TF extracts may constitute a new source of glucose transport activator and could be employed as a potential anti-diabetic material for treatment and preventing diabetes.

Factors Affecting Oxygen Uptake by Yeast Issatchenkia orientalis as Microbial Feed Additive for Ruminants

  • Lee, J.H.;Lim, Y.B.;Park, K.M.;Lee, S.W.;Baig, S.Y.;Shin, H.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1011-1014
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    • 2003
  • The objective of this work was to evaluate a thermotolerant yeast Issatchenkia orientalis DY252 as a microbial feed additive for ruminants. In the present study, the influence of volatile fatty acids (VFA) and temperature on oxygen uptake rate by I. orientalis DY 252 was investigated. It was evident that the oxygen uptake rate was decreased gradually as the VFA concentrations increased in a range of 30 to 120 mM. Although the oxygen uptake rate was not greatly affected by temperature in the range 37 to $43^{\circ}C$, a maximum value of $0.45mg\;O_2/g$ cell/ min was obtained at $39^{\circ}C$. With regard to the oxygen uptake rate by yeast, viability was found to be less important than the metabolic activity of yeast.

Biosorption of Heavy Metal Sons by Biomass of Marine Brown Algae in Cheju using Their immobilization Techniques: Biosorption of Copper by Undaria pinnatifida

  • Sang-Kyu Kam;Min-Gyu Lee
    • Journal of Environmental Science International
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    • v.1 no.2
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    • pp.157-166
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    • 1992
  • The biosorptlon perFormances of copper were Investigated by the immobilized biomass of nonliving marine brown algae Undaria pinnatifida by each of the Ca-alginate method(Ca-ALG), Ba-alginate method(Ba-ALG), polyethylene glycol method(PEG), and carrageenan method (CARR). The copper removal performance increased but the copper uptake decreased as the biomass amount was increased. However, the copper uptake by the immobilized biomass increased with increasing initial copper concentration. Among the immobilization methods, the copper uptake decreased in the following sequence: Ca-ALG > Ba-ALG > PEG > CARR. The pattern of copper uptake by the immobilized biomass fitted the Langmuir isotherm better than the Freundlich isotherm. Desorption of deposited copper with 0.05 ~0.5M HCI, resulted in no changes of the copper uptake capacity of the immobilized biomass by the immobilization methods except for PEG, through five subsequent biosorptioydesorption cycles. There was no damage to the immobilized biomass which retained its macroscopic appearance in repeated copper uptake/elution cycles.

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Preparation and Cellular Uptake of Hydrophobic Quantum Dots Encapsulated in Poly-L-Lactic Acid Film (소수성 양자점을 함유한 Poly-L-Lactic Acid film의 제조 및 세포흡수 연구)

  • Lee, Ji-Sook;Woo, Kyoung-Ja;Chung, He-Sson
    • Journal of Pharmaceutical Investigation
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    • v.39 no.1
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    • pp.1-6
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    • 2009
  • To overcome the stability problem of hydrophilic quantum dot (Q-dot), cellular uptake of hydrophobic instead of hydrophilic Q-dot was studied in the hope to find a simple method to use Q-dot as a cellular imaging probe. Hydrophobic Q-dot and poly-L-lactic acid (PLLA) were co-dissolved in chloroform to prepare stable films. Due to the cellular compatibility of PLLA, adherent cells were cultured on the film to observe the degree of Q-dot uptake and cytotoxicity of the prepared films. The results show that Q-dots were absorbed into NIH3T3 and EMT6 cells. Cellular uptake was also observed when hydrophobic Q-dots were coated directly on a glass plate. PLLA/Q-dot film and Q-dot coated on glass plate did not show major cytotoxicity. In vivo tumor model was also used to show the uptake of Q-dot from the PLLA/Q-dot film to the tumor site.

FUNCTIONAL EXPRESSION OF A PEPTIDE TRANSPORTER IN XENOPUS OOCYTES

  • Oh, Doo-Man
    • Journal of Pharmaceutical Investigation
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    • v.23 no.3
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    • pp.31-40
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    • 1993
  • It is essential to clone the peptide transporter in order to obtain better understanding of its molecular structure, regulation, and substrate specificity. Characteristics of an endogenous peptide transporter in oocytes were studied along with expression of an exogenous proton/peptide cotransporter from rabbit intestine. And further efforts toward cloning the transporter were performed. The presence of an endogenous peptide transporter was detected in Xenopus laevis oocytes by measuring the uptake of $0.25\;{\mu}M\;(10\;{\mu}Ci/ml)\;[^3H]-glycylsarcosine$ (Gly-Sar) at pH 5.5 with or without inhibitors. Uptake of Gly-Sar in oocytes was significantly inhibited by 25 mM Ala-Ala, Gly-Gly, and Gly-Sar (p<0.05), but not by 2.5 mM of Glu-Glu, Ala-Ala, Gly-Gly, Gly-Sar and 25 mM glycine and sarcosine. This result suggests that a selective transporter is involved in the endogenous uptake of dipeptides. Collagenase treatment of oocytes used to strip oocytes from ovarian follicles did not affect the Gly-Sar uptake. Changing pH from 5.5 to 7.5 did not affect the Gly-Sar uptake significantly, suggesting no dependence of the endogenous transporter on a transmembrane proton gradient. An exogenous $H^+/peptide$ cotransporter was expressed after microinjection of polyadenylated messenger ribonucleic acid $[poly\;(A)^+-mRNA]$ obtained from rabbit small intestine. The Gly-Sar uptake in mRNA-injected oocytes was 9 times higher than that in water-injected oocytes. Thus, frog oocytes can be utilized for expression cloning of the genes encoding intestinal $H^+/peptide$ cotransporters. Using the technique size fractionation of mRNA was sucessfully obtained.

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Nitrate Uptakes by Microorganisms Isolated from the Soils of Greenhouse

  • Cho, Kwang-Hyun;Lee, Gyeong-Ja;Ahn, Hae-Jin;Kim, Young-Kee
    • Journal of Applied Biological Chemistry
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    • v.48 no.1
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    • pp.11-15
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    • 2005
  • Salinity of soils in greenhouse has been increased by massive application of fertilizers. Nitrogen fertilizer was most popular, and thus nitrate became the majority of soil salinity. Accumulation of nitrate led to deleterious effects on the growth and development of crops and vegetables. Microbial strains able to utilize nitrate and thus remove excess nitrate from farm land soils were isolated from 15 different soils of greenhouses and plastic film houses. Four strains able to grow in medium containing 50 mM $KNO_3$ were isolated, among which only E0461 showed high capacity of nitrate uptake. Nitrate uptake by E0461 was dependent on culture medium and was increased by addition of tryptone and peptone. Although E0461 was able to grow without tryptone and peptone, growth was slow, and no nitrate uptake was observed. Nitrate appeared to facilitate E0461 growth in the presence of tryptone and peptone. Through kinetic analysis, nitrate uptake was measured at various concentrations of nitrate, and half-life was calculated. Nitrate concentration decreased with increasing incubation period, and plot between half-lives and initial concentrations of nitrate fitted to single exponential function. These results suggest one major factor plays an important role in microbial nitrate uptake.