• Journal of Korean Dental Science
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• 제4권2호
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• pp.73-78
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• 2011

Purpose: $HCO_3{^-}$ is the most important ion to buffer the acidity of saliva. The transport of $HCO_3{^-}$ is mediated by electrogenic $Na^+/HCO_3{^-}$ cotransporter 1 (NBCe1), which expressed in various tissues including salivary glands, kidney and pancreas, etc. This experiment was performed to investigate regulatory site of NBCe1involved in the pH regulation using various mutants of NBCe1. Materials and Methods: Human parotid gland NBCe1 (hpNBCe1) and mutants by deletion of 1~285 bp and 1~1,035 bp were prepared. After microinjection of each cRNA to oocytes of Xenopus laevis, they were incubated for 2~3 days. The function of each protein was tested by electrophysiological method. Results: When oocytes were exposed to the $HCO_3{^-}$ buffered solution, 1~285 bp deleted mutant hpNBCe1 evoked a marked hyperpolarization ranging from -90 mV to -160 mV (average: -134 mV; n=12) compared to the full length of hpNBCe1. Although 1~1,035 bp deleted mutant hpNBCe1 was also expressed in the plasma membrane, but it did not show any changes of membrane potentials. Conclusion: Our deletion mutant study demonstrated that 1~285 bp of the NBCe1 is the major domain to determine $HCO_3{^-}$ transport ratio.

• 한국발생생물학회지:발생과생식
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• 제22권3호
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• pp.263-273
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• 2018

Aquaporin (AQP) 3, a facilitated transporter of water and glycerol, expresses in placenta and fetal membranes, but the detailed localization and function of AQP3 in placenta remain unclear. To elucidate a role of AQP3 in placenta, we defined the expression and cellular localization of AQP3 in placenta and fetal membranes, and investigated the structural and functional differences between wild-type and AQP3 null mice. Gestational sacs were removed during mid-gestational period and amniotic fluid was aspirated for measurements of volume and composition. Fetuses with attached placenta and fetal membranes were weighed and processed for histological assessment. AQP3 strongly expressed in basolateral membrane of visceral yolk sac cells of fetal membrane, the syncytiotrophoblasts of the labyrinthine placenta and fetal nucleated red blood cell membrane. Mice lacking AQP3 did not exhibit a significant defect in differentiation of trophoblast stem cells and normal placentation. However, AQP3 null fetuses were smaller than their control litter mates in spite of a decrease in litter size. The total amniotic fluid volume per gestational sac was reduced, but the amniotic fluid-to-fetal weight ratio was increased in AQP3 null mice compared with wild-type mice. Glycerol, free fatty acid and triglyceride levels in amniotic fluid of AQP3 null mice were significantly reduced, whereas lactate level increased when compared to those of wild-type mice. These results suggest a role for AQP3 in supplying nutrients from yolk sac and maternal blood to developing fetus by facilitating transport of glycerol in addition to water, and its implication for the fetal growth in utero.

• 전기화학회지
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• 제8권4호
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• pp.177-180
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• 2005

유 무기 혼성 막의 계열은 티타니움 디옥사이드 나노파티클 함량의 체계적인 변화에 의해 조제된다. 유 무기 혼성 막의 수분함량, 메탄올 투과도와 전자 전도 특성은 무기 산화물의 함량의 기능에 따라 연구된다. 그 결과 망상구조의 무기 산화물은 전자 전도 특성과 수분함량의 감소를 보였다. 또한 무기 산화물의 함량이 증가할수록 메탄올 투과도도 감소함을 나타내었다. 형태학적인 관점에서 막은 폴리머 기반과 무기영역 사이에 균일하고 잘 점착됨을 보여준다. 혼성막의 특성은 나피온막과 비교 실험되었다.

• Membrane and Water Treatment
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• 제3권2호
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• pp.123-131
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• 2012

This study investigated the extraction and stripping performance of PIMs consisting of PVC and Aliquat 336. Extraction and stripping of three representative heavy metals - namely $Cd^{2+}$, $Cu^{2+}$, and $Zn^{2+}$ - by the synthesized membranes were evaluated as a function of sodium chloride concentration and under different stripping solutions (0.01 M $HNO_3$, Milli-Q water, 0.01 M HCl and 0.01 M NaOH), respectively. Results reported here indicate that the formation of negatively charged metal chloride complex species was responsible for the extraction of the target metal to PIMs. Experimental results and thermodynamic modeling of the speciation of chloro metal complexes further confirm that the extraction selectivity between $Cd^{2+}$, $Cu^{2+}$ and $Zn^{2+}$ can be controlled by regulating the chloride concentration of the feed solution. An acidic solution without any chloride was the most effective stripping solution, followed by Milli-Q water, and a diluted hydrochloric acid solution. On the other hand, the stripping of metals from PIMs did not occur when a basic stripping solution was used.

• The Korean Journal of Physiology and Pharmacology
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• 제1권1호
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• pp.35-43
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• 1997

Cis-dichlorodiammine platin${\mu}M$II (Cisplatin), an effective chemotherapeutic agent, induces acute renal failure by unknown mechanisms. To investigate direct toxic effects of cisplatin on the renal proximal tubular transport system, LLC-$PK_1$ cell line was selected as a cell model and the sugar transport activity was evaluated during a course of cisplatin treatment. Cells grown to confluence were treated with cisplatin for 60 min, washed, and then incubated for up to 5 days. At appropriate intervals, cells were tested for sugar transport activity using ${\alpha}-methyl-D-[^{14}C]glucopyranoside$ (AMG) as a model substrate. In cells treated with 100 ${\mu}M$ cisplatin, the AMG uptake was progressively impaired after 3 days. The viability of cells was not substantially changed with cisplatin of less than 100 ${\mu}M$, but it decreased markedly with 150 and 200 ${\mu}M$. In cisplatin-treated cells, the $Na^+$ -dependent AMG uptake was drastically inhibited with no change in the $Na^+$ -independent uptake. Kinetic analysis indicated that Vmax was suppressed, but Km was not altered. The $Na^+$ -dependent phlorizin binding was also decreased in cisplatin-treated cells. However, the AMG efflux from preloaded cells was not apparently retarded by cisplatin treatment. These data indicate that the cisplatin treatment impairs $Na^+$ -hexose cotransporters in LLC-$PK_1$ cells and suggest strongly that defects in transporter function at the luminal plasma membrane of the proximal tubular cells constitute an important pathogenic mechanism of cisplatin nephrotoxicity.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.194-194
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• 2017

Camelina (Camelina sativa L.) is a potential bio-energy crop that has short life cycle about 90 days and contains high amount of unsaturated fatty acid which is adequate to bio-diesel production. Enhancing environmental stress tolerance is a main issue to increase not only crop productivity but also big mass production. CsRCI2s (Rare Cold Inducible 2) are cold and salt stress related protein that localized at plasma membrane (PM) and assume to be membrane potential regulation factor. These proteins can be divide into C-terminal tail (CsRCI2D/E/F/G) or no-tail group (CsRCI2A/B/C/H). However, function of CsRCI2s are less understood. In this study, physiological responses and functional characterization of CsRCI2s of Camelina under salt stress were analyzed. Full-length CsRCI2s (A/B/E/F) and CsPIP2;1 sequences were confirmed from Camelina genome browser. Physiological investigations were carried out using one- or four-week-old Camelina under NaCl stress with dose and time dependent manner. Transcriptional changes of CsRCI2A/B/E/F and CsPIP2;1 were determined using qRT-PCR in one-week-old Camelina seedlings treated with NaCl. Translational changes of CsRCI2E and CsPIP2;1 were confirmed with western-blot using the antibodies. Water transport activity and membrane potential measurement were observed by cRNA injected Xenopus laevis oocyte. As results, root growth rate and physiological parameters such as stomatal conductance, chlorophyll fluorescence, and electrolyte leakage showed significant inhibition in 100 and 150 mM NaCl. Transcriptional level of CsPIP2;1 did not changed but CsRCI2s were significantly increased by NaCl concentration, however, no-tail type CsRCI2A and CsRCI2B increased earlier than tail type CsRCI2E and CsRCI2F. Translational changes of CsPIP2;1 was constitutively maintained under NaCl stress. But, accumulation of CsRCI2E significantly increased by NaCl stress. CsPIP2;1 and CsRCI2A/B/E/F co-expressed Xenopus laevis oocyte showed decreased water transport activity as 61.84, 60.30, 62.91 and 76.51 % at CsRCI2A, CsRCI2B, CsRCI2E and CsRCI2F co-expression when compare with single expression of CsPIP2;1, respectively. Moreover, oocyte membrane potential was significantly hyperpolarized by co-expression of CsRCI2s. However, higher hyperpolarized level was observed in tail-type CsRCI2E and CsRCI2F than others, especially, CsRCI2E showed highest level. It means transport of $Na^+$ ion into cell is negatively regulated by expression of CsRCI2s, and, function of C-terminal tail is might be related with $Na^+$ ion influx. In conclusion, accumulation of NaCl-induced CsRCI2 proteins are related with $Na^+$ ion exclusion and prevent water loss by CsPIP2;1 under NaCl stress.

• 멤브레인
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• 제10권1호
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• pp.39-46
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• 2000

분리막 접촉기를 통한 이산화탄소의 흡수거동 예측을 위한 공정모사를 위해 시스템의 흡수제로 탄산칼륨 수용액을 선정하였고, 시스템에서의 이산화탄소와 관련된 가역반응을 고려하였으며, 사용된 반응속도상수, 평형상수, 용해도 그리고 확산계수는 탄산이온의 농도와 온도의 함수로 사용하였다. 또한 분리막 접촉기 공정모사를 위한 조작 조건으로 중공사막의 기공상태는 비젖음성 조건을 선택하였으며, 이러한 조작조건하에서 이산화탄소 분리거동을 다양한 공정변수 즉, 흡수제의 농도와 유속, 혼합기체의 압력변화에 대해 고찰하였다. 흡수제의 농도가 증가함에 따라 촉진수송에 의한 이산화탄소의 흡수거동을 확인할 수 있었고, 흡수제의 유속 증가에 따라 이산화탄소의 흡수속도가 점차 증가함을 확인할 수 있었으며, 분리막 접촉기에서 혼합기체의 압력변화가 흡수속도에 미치는 영향 및 흡수제의 재사용에 따른 흡수속도를 확인할 수 있었다. 이러한 공정모사를 통해 분리막 접촉기의 구성 및 조작에 필요한 각각의 인자들이 흡수속도에 미치는 영향과 예측, 이를 통한 적절한 조작조건의 도출 가능성을 확인할 수 있었다.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.37-43
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• 1997

Triphenylmethane was decolorized rapidly by enterbacter cloacae MG 82 at initial reaction time. The spheroplast showed higher activity of triphenylmentane decolorization than that of intact cell suspension. The outer part of the bacterial cell envelope and the peptidoglycan are important for the function of transport barrier of triphenylmethane. In intact cell, decolorization activity was higher at 37$\circ $C than at $\circ $C, indicating that triphenylmethane decolorization is due to the enzyme reaction. Culture filtrate showed no decolorization activity, while cell-free extract appeared high activity of 1.45 units, clearly showing that decolorization activity was due to the cell-free extract. Comparing decolorization activities of cell fractions, it was found that decolorization activity was located at the compartment of cytoplasmic membrane. The enzyme activity was also shown to be Mg$^{++}$-dependent. The optimum pH and temperature of enzyme activity were 7.0 and 50$\circ $C, respectively. The thermostability of this enzyme at 35$\circ $C was kept to 58% for 3 hours.

• Applied Microscopy
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• 제20권2호
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• pp.117-126
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• 1990

Structural changes of the vitelline envelopes during oogenesis of a polychaete, Nectoneanthes oxypoda, were examined with a scanning electron micrscope. Oocytes grow in the same coelomic fluid to the final stage, but the surface appears to change in the structure during oogenesis. Projections, which were identified to be microvilli, change in shape, number and size. Short microvilli, which cover the surface of oocyte of $33{\mu}m$ diameter densely, grow in length, reaching a maximum at the stage of $73{\mu}m$. The number of microvilli increases with the stages of oogenesis, reaching a plateau at the stage of $82{\mu}m$. The observations suggest that control of material transport including yolk precursor proteins may be correlated with the structural changes in the microvilli.

• Journal of Pharmaceutical Investigation
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• 제7권1_4호
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• pp.22-27
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• 1977

Absorption of sulfisoxazole after oral administration was significantly increased by small dose(60mg/kg) of alloxan but not increased significantly by large dose (160mg/kg) of alloxan from that of normal rabbits. Pretreatment with alloxan did not give any effect on clearance of sulfisoxazole. As the results, It could come to conclusion that in creased absorption of the sulfisoxazole administered small dose of the alloxan was influenced by transport of intestinal membrane or intestinal enzyme activation or increase of intestinal absorption function.