• Title/Summary/Keyword: uptake

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Biosorption of Pb and Cu by Kjellmaniella crassifolia (개다시마를 이용한 Pb 및 Cu 흡착)

  • 안갑환;서근학;오창섭
    • Journal of Environmental Science International
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    • v.7 no.5
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    • pp.653-658
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    • 1998
  • Marine algaes are capable of binding a large quantity of heavy metals. We have investigated the uptake capacity of Pb and Cu by using 22 species of marine algae. collected from Korean coast. Among a variety of different marine algae types for biosorbent potential. Kjellmaniella crassifolia showed the highest uptake capacity of Pb. Metal uptake of Pb and Cu by Kjellmaniella crassifolia increase as the initial concentration rises, as long as binding sites are remained. The metal uptake parameters for Pb and Cu had been determined according to Langmuir and Freundlich model. By increasing pH, Pb uptake was increased and Cu uptake was constant. The maximum uptake capacity of Pb and Cu by Kjellmaniella crassifolia was 437 mg/g and 129 mg/g, respectively.

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Characterization of the Hepatic Uptake of l-Anilino-8-naphthalene sulfonate(ANS) by Isolated Rat Hepatocytes-Is Serum Protein Essential for Hepatic Uptake of ANS in the Liver?- (유리간세포를 사용한 ANS의 간내 이행에 관한 연구-ANS의 간내 이행과정에 단백질 매개 기구가 존재하는가?-)

  • Chung, Youn-Bok;Yuk, Dong-Yeon;Han, Kun
    • Journal of Pharmaceutical Investigation
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    • v.21 no.1
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    • pp.43-50
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    • 1991
  • The hepatic uptake of an anionic fluorescence probe, l-anilino-8-naphthalene sulfonate (ANS) was characterized using isolated rat hepatocytes. The initial uptake rate of ANS by isolated hepatocytes was determined. The uptake process of ANS was fitted well to the Michaelis-Menten equation with a saturable component. The $V_{max}$ and $K_m$ values were $2.9{\pm}0.1\;nmol/min/mg$ protein and $29.1{\pm}3.2\;{\mu}M$, respectively. The uptake clearance $(CL_{up})$ based on the ratio of $V_{max}$ to $K_m$ was 11.7 ml/min/g liver, revealing the good coincidence with that assessed from the analysis of the plasma disappearance curve in previous report. Furthermore, the effect of serum protein on the hepatic uptake of ANS into isolated hepatocytes was investigated. The permeability clearances $(PS_{inf})$ of ANS uptake were much higher than those predicted based on the unbound fractions in the presence of serum. These suggested that the hepatic uptake of extensively serum protein-bound ANS is mediated not only by the unbound form of ligand but also by the serum protein-mediated uptake mechanism.

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Analysis of Diffuse Hepatic Visualization after Iodine-131 Treatment in Patients with Thyroid Carcinoma (갑상선암 환자에서 전절제술 후 I-131 치료에서 미만성 간침착 정도의 분석)

  • Jung Jin-Hyung;Bae Keum-Seok;Kang Seong-Joon
    • Korean Journal of Head & Neck Oncology
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    • v.16 no.2
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    • pp.206-211
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    • 2000
  • Objectives: Any uptake of I-131 after total thyroidectomy means the remant thyroid tissue or distant metastasis of the thyroid cancer. However diffuse hepatic uptake of I-131 without abnormal uptake was showen in many cases on I-131 whole body scan. The aim of this study was to classify the liver uptake after I-131 scan and to evaluate the analysis of this finding. Materials and Methods: Between 1982 and 1998, 104 patients(l4 males, 90 females) with normal liver function underwent I-131 scan after total thyroidectomy. Prospectively we reviewed the films of the whole body scan and analysed the correlations between results of radioiodine uptake, pathologic diagnosis, prognostic factors, lymphatic metastasis, and thyroid function test. Result: Diffuse hepatic uptake was found in 44 of 104(42%) patients. 10 of 39(26%) patients on I-131 100mCi, and 34 of 63(54%) on I-131 150mCi showed hepatic uptake. 52 of 104(50%) patients was locally invasive thyroid cancer. The rate of the hepatic uptake was no significant differences with the thyroid hormone levels(T3, Free T4) and thyroglobulin between uptake group and non-uptake group. Conclusion: The rate of I-131 uptake was high in high-dose radioiodine treatment group. However, we can not find any correlation among the thyroid functions, the extent of metastasis or the extent of local invasion. We need further study to find out the causes of the hepatic uptake of I-131 after total thyroidectomy, besides liver metabolism of I-131 attached thyroid hormones.

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Evidence for Sulfite Proton Symport in Saccharomyces cerevisiae

  • Park, Hoon;Alan T. Bakalinsky
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.967-971
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    • 2004
  • The kinetics of sulfite uptake were examined in a wild-type laboratory strain of Saccharomyces cerevisiae to determine if carrier-mediated sulfite uptake involved a proton symport, as previous studies on sulfite uptake have suggested both an active process and facilitated diffusion. Accumulation of intracellular sulfite was initially rapid and linear up to 50 sec. Uptake was saturable at final concentrations equal to or greater than 3 mM sulfite, and increased 2-fold in the presence of 2% glucose. Uptake was significantly reduced in cells pretreated with 100-500 $\mu$M carbonyl cyanide mchlorophenylhydrazone (CCCP) or 2,4-dinitrophenol (DNP), both of which dissipate proton gradients. Uptake was also significantly inhibited in the presence of 1 mM arsenate, an inhibitor of ATP synthesis. Extracellular alkalization was observed in cells incubated with 1-2 mM sulfite in a weak tartrate buffer at pH 3.5 and 4.5. These findings suggest that the bisulfite ion, $HSO_3^-$, an anionic form of sulfite, is taken up by a carrier-mediated proton symport. A met16 sull sul2 mutant, impaired in both sulfite formation and sulfate uptake, was found able to grow on a medium with sulfite as the sole Sulfur source, indicating that the sulfate transporters Sul1p and Sul2p are not required for sulfite uptake.

Uptake of a Dipeptide by the Dipeptide Transporter in the HT-29 Intestinal Cells (HT-29 장관세포에 있는 디펩티드수송체에 의한 디펩티드의 흡수)

  • Oh, Doo-Man
    • Journal of Pharmaceutical Investigation
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    • v.25 no.2
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    • pp.137-143
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    • 1995
  • The peptide transporter can be utilized for improving the bioavailability of compounds that are poorly absorbed. Characterization of the dipeptide uptake into the human intestinal epithelial cells, HT-29 was investigated. The uptake of tritiated glycylsarcosine $([^3H]-Gly-Sar,\;0.1\;{\mu}Ci/ml)$ was measured in confluent or subconfluent HT-29, Caco-2, and Cos-7 cells. Uptake medium was the Dulbecco's Modified Eagle's Media (DMEM) adjusted to pH 6.0. Both HT-29 and Caco-2 cells expressed the dipeptide transporter significantly (p<0.005) but Cos-7 did not. Certain portions of passive uptake were observed in all three cell lines. Uptake of Gly-Sar was largest at 7 days after plating HT-29 cells with significant inhibition with 25 mM cold Gly-Sar (p<0.05). but expression ratio of the dipeptide transporter was 0.7, suggesting lower expression. The effect of pH on Gly-Sar uptake was not significant in the range of pH 6 to 8. Gly-Sar uptake was also inhibited with 50 mM carnosine, 25 mM Gly-Sar, and 35 mM cephalexin significantly (p<0.05). From above results the dipeptide transporter was expressed well in HT-29 cells and was similar to that in the small intestine, suggesting that large amounts of mRNA of the transporter from the cells can be obtained.

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Rate of Oxygen Uptake in Antheraea mylitta in Various Stages of Development and during Diapause

  • Rath S. S.;Negi B. B. S.;Singh B. M. K.;Thangavelu K.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.10 no.1
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    • pp.45-49
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    • 2005
  • Respiration in Antheraea mylitta was studied using constant pressure respirometer. Oxygen uptake in different stages of life showed that moth has highest rate of oxygen uptake as compared to larva and pupa. At each stage significant sexual differentiation was observed. Depression in the rate of oxygen uptake in diapausing pupa was found to be higher in male ($65.75\%$) than female ($60.65\%$) as compared to non-diapausing counterparts. During diapause lowest oxygen uptake was recorded in the month of February, and were in the order of February < January < December < March < November < April < May < June in male, and, February < January < December < March < April < November < May < June in female. Significant sexual differentiation in oxygen uptake was recorded throughout the period of diapause (November to June) where female pupae registered lower rate of oxygen uptake than that of male. Oxygen uptake in female pupae declined upto $28.89\%$ in non-diapausing and $18.29\%$ in diapausing broods over male. Highest respiratory quotient value was recorded in the moth of November (0.68 in male and 0.70 in female) and, the lowest in the month of March in male (0.54) and May in female (0.55). Percentage loss in pupa weight always remained at a significantly higher level in male (except in February and March). The lowest oxygen uptake rate and weight loss in the month of February shows that the pupae were at peak of their dormancy during this month.

Effect of t-butylhydroperoxide on $Na^+-dependent$ Glutamate Uptake in Rabbit Brain Synaptosome

  • Lee, Hyun-Je;Kim, Yong-Keun
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.4
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    • pp.367-376
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    • 1997
  • The effect of an organic peroxide, t-butylhydroperoxide (t-BHP), on glutamate uptake was studied in synaptosomes prepared from cerebral cortex. t-BHP inhibited the $Na^+-dependent$ glutamate uptake with no change in the $Na^+-independent$ uptake. This effect of t-BHP was not altered by addition of $Ca^{2+}$ channel blockers (verapamil, diltiazem and nifedipine) or $PLA_2$ inhibitors (dibucaine, butacaine and quinacrine). However, the effect was prevented by iron chelators (deferoxamine and phenanthroline) and phenolic antioxidants (N,N'-diphenyl-phenylenediamine, butylated hydroxyanisole, and butylated hydroxytoluene). At low concentrations (<1.0 mM), t-BHP inhibited glutamate uptake without altering lipid peroxidation. Moreover, a large increase in lipid peroxidation by $ascorbate/Fe^{2+}$ was not accompanied by an inhibition of glutamate uptake. The impairment of glutamate uptake by t-BHP was not intimately related to the change in $Na^+-K+-ATPase$ activity. These results suggest that inhibition of glutamate uptake by t-BHP is not totally mediated by peroxidation of membrane lipid, but is associated with direct interactions of glutamate transport proteins with t-BHP metabolites. The $Ca^{2+}$ influx through $Ca^{2+}$ channel or $PLA_2$ activation may not be involved in the t-BHP inhibition of glutamate transport.

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Precipitation Decreases Methane Uptake in a Temperate Deciduous Forest (온대 낙엽 활엽수림에서의 강수량에 따른 메탄 흡수 감소)

  • Khokhar, Nadar Hussain;Park, Jae-Woo
    • Journal of Soil and Groundwater Environment
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    • v.24 no.1
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    • pp.24-34
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    • 2019
  • Soil moisture regulates the fate of methane ($CH_4$) in forest soil via biological and chemical processes. The instant effect of variable precipitation on $CH_4$ uptake is, however, unclear in the forest ecosystems. Here, we measured $CH_4$ flux in a temperate forest soil immediately after variable volume of water applications equivalent to 10, 20 40, and $80mm\;m^{-2}day^{-1}$ precipitation. $CH_4$ uptake was significantly higher when the water was not applied. The $CH_4$ uptake decreased significantly with increasing water application. $CH_4$ uptake was linked with air filled porosity and water filled porosity. $CH_4$ uptake response to actual precipitation intensity was in agreement with $CH_4$ uptake results in this study. $CH_4$ uptake decreased 55% at highest precipitation intensity. Since annual $CH_4$ flux is calculated with interpolation of weekly or biweekly field observations, instant effect of precipitation can mislead the interpolated annual results.

Correlation between 5-Minute $^{99m}Tc-Pertechnetate$ Uptake and 24-Hour $^{131}I$ Uptake in Patients with Thyroid Disease (갑상선환자에서의 5분 $^{99m}Tc-Pertechnetate$ 섭취율과 방사성옥소섭취율의 상관관계)

  • Lee, Chan-Woo;Won, Kyu-Chang;Yoon, Hyun-Dae;Cho, In-Ho;Kim, Tae-Nyeun;Shin, Dong-Gu;Lee, Hyoung-Woo;Shim, Bong-Sup;Lee, Hyun-Woo
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.2
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    • pp.280-289
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    • 1992
  • The 20-minute $^{99m}Tc-pertechnetate$ uptake became readily available for routine use and it replaced $^{131}I$ for thyroid imaging. However measuring thyroid uptake during a 5-minute minimizes pertechnetate uptake by the salivary glands and presence of contaminated saliva from those glands in to the pharynx and esophagus. A study was carried out to determine the suitability of the utility of a S-minute and 20-minute interval from administration of $^{99m}Tc-pertechnetate$ to imaging and uptake measurement as a replacement for the 24 hour standard originally established with $^{131}I$, and to evaluate the relationship between 5-minute $^{99m}Tc-pertechnetate$ uptake and other thyroid functions. A 5-minute and 20-minute uptake of $^{99m}Tc-pertechnetate$ were measured in 70 patients with thyroid disease at Yeungnam University Hospital from March 1, 1991 to Feb. 29, 1992. The results were as follows. 1) The 5-minute $^{99m}Tc-pertechnetate$ uptake in Graves' disease, Hashimoto's thyroiditis, simple goiter, non toxic nodular goiter, subacute thyroiditis and euthyroid were 18.2%, 14.6%, 2.8%, 3.2%, 1.2% and 1.1%, respectively. There was a significant difference between the mean of the euthyroid group and the mean of the Graves' disease. So differenciation between them can be easily made. 2) The 5 minute $^{99m}Tc-pertechnetate$ thyroid uptake was well correlated with 24 hour $^{131}I$ thyroid uptake (r=0.75, p<0.001). These data provided an equation for estimating the 24 hour uptake of iodide given the 5 minute pertechnetate uptake: Estimated 24-hour $^{131}I$ thyroid Uptake= 7.188*ln (5 minute $^{99m}Tc-pertechnetate$ uptake)+16.94 3) The 20-minute $^{99m}Tc-pertechnetate$ thyroid uptake was well correlated with 24-hour $^{131}I$ uptake (r=0.72, p<0.001) and 5-minute $^{99m}Tc-pertechnetate$ thyroid uptake (r=0.96, p<0.001). 4) In the Graves' disease, The 5-minute $^{99m}Tc-pertechnetate$ thyroid uptake was well correlated with serum $T_3-resin$ uptake (r=0.46, p<0.01), serum total $T_3$ (r=0.55, p<0.05), serum total $T_4$ (r=0.46, p<0.05). These results suggest that 5-minute ${99m}Tc-pertechnetate$ thyroid uptake has been found at least as useful as 24-hour $^{131}I$ uptake for diagnostic confirmation at our hospital, the logistical advantages of completing the diagnosis. The exam in 5-minutes led us to abandon the 24-hour study in the majority of patients, but the 24-hour $^{131}I$ uptake is still obtained in patients with planned or potential radioiodine therapy.

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Effects of insulin and IGF on growth and functional differentiation in primary cultured rabbit kidney proximal tubule cells - Effects of IGF-I on Na+ uptake - (초대배양된 토끼 신장 근위세뇨관세포의 성장과 기능분화에 대한 insulin과 IGF의 효과 - Na+ uptake에 대한 IGF-I의 효과 -)

  • Han, Ho-jae;Park, Kwon-moo;Lee, Jang-hern;Yang, IL-suk
    • Korean Journal of Veterinary Research
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    • v.36 no.4
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    • pp.783-794
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    • 1996
  • It has been suggested that ion transport systems are intimately involved in mediating the effects of growth regulatory factors on the growth of a number of different types of animal cells in vivo. The functional importance of the apical membrane $Na^+/H^+$ antiporter in the renal proximal tubule is evidenced by estimates that this transporter mediates the reabsorption of approximately one third of the filtered load of sodium and the bulk of the secretion of hydrogen ions. This study was designed to investigate the pathway utilized by IGF-I in regulating sodium transport in primary cultured renal proximal tubule cells. Results were as follows : 1. $Na^+$ was observed to accumulate in the primary cells as a function of time. Raising the concentration of extracellular NaCl induced an decrease in $Na^+$ uptake compared with control cells in a dose dependent manner. The rate of $Na^+$ uptake into the primary cells was about two times higher in the absence of NaCl($40.11{\pm}1.76pmole\;Na^+/mg\;protein/min$) than in the presence of 140mM NaCl($17.82{\pm}0.94pmole\;Na^+/mg\;protein/min$) at the 30 minute uptake. 2. $Na^+$ uptake was inhibited by IAA($1{\times}10^{-4}M$) or valinomycin($5{\times}10^{-6}M$) treatment($50.51{\pm}4.04$ and $57.65{\pm}2.27$ of that of control, respectively). $Na^+$ uptake by the primary proximal tubule cells was significantly increased by ouabain($5{\times}10^{-5}M$) treatment($140.23{\pm}3.37%$ of that of control). When actinomycin D($1{\times}10^{-7}M$) or cycloheximide($4{\times}10^{-5}M$) was applied, $Na^+$ uptake was decreased to $90.21{\pm}2.39%$ or $89.64{\pm}3.69%$ of control in IGF-I($1{\times}10^{-5}M$) treated cells, respectively. 3. Extracellular cAMP decreased $Na^+$ uptake in a dose-dependent manner($10^{-8}-10^{-4}M$). IBMX($5{\times}10^{-5}M$) also inhibited $Na^+$ uptake. Treatment of cells with pertussis toxin(50pg/ml) or cholera toxin($1{\mu}g/ml$) inhibited $Na^+$ uptake. Extracellular PMA decreased $Na^+$ uptake in a dose-dependent manner(1-100ng/ml). 100 ng/ml PMA concentration significantly inhibited $Na^+$ uptake in IGF-I treated cells. However, staurosporine($1{\times}10^{-7}M$) had no effect on $Na^+$ uptake. When PMA and staurosporine were added together, the inhibition of $Na^+$ uptake was not observed. In conclusion, sodium uptake in primary cultured rabbit renal proximal tubule cells was dependent on membrane potentials and intracellular energy levels. IGF-I stimulates sodium uptake through mechanisms that involve some degree of de novo protein and/or RNA synthesis, and cAMP and/or PKC pathway mediating the action mechanisms of IGF-I.

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