• 한국ITS학회:학술대회논문집
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• 한국ITS학회 2002년도 제1회 정기총회 및 학술대회
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• pp.185-188
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• 2002

• 한국환경과학회지
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• 제11권10호
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• pp.1023-1030
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• 2002

The effects on photosynthesis of NaCl(0, 0.2, 0.4, 0.6, 0.8 or 1.0 M) were examined in etiolated barley seedlings. Chlorophyll(Chl) a, Chl b and carotenoid contents, Chl a fluorescence and quenching coefficients of Chl fluorescence have been determined in the primary leaves of etiolated barley seedlings cultivated under low light(60 $\mu$㏖ $m^{-2}\;s^{-1}$). Chl a, b, and carotenoid contents were decreased remarkably in comparison with the control at 0.4 M NaCl. However, the value of Fo and Fv were decreased at 0.6 M NaCl and the ratio of Fv/Fm were deceased at 1.0 M NaCl. Chlorophyll synthesis was seriously inhibited from 0.4 M NaCl, and the photosynthetic electron transport system was inhibited from 0.6 M NaCl. Quantum of photosystem II reaction center was inhibited at 1.0 M NaCl. The effects of NaCl on the Chl content were raised in a 6 hrs, but the effects of NaCl on the value of Fo, Fv and Fv/Fm were raised in 30 hrs. The value of qP was decreased in comparison with the control at all concentrations, but there was a small change in the value qE. These results provide evidence that NaCl inhibited effects of various concentration of NaCl were inhibited quinone redox, however, proton gradient between thylakoid membranes was little damaged.

• 한국식품영양과학회지
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• 제31권5호
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• pp.775-781
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• 2002

hTATl에 의해 수송되는 방향족 아미노산들의 수송특성을 밝히기 위해 hTATl의 cRNA를 미세주입한 Xenopus laevis oocyte에서 hTATl에 의 해 유도되는 방향족 아미노산의 up-take를 여러 조건 하에서 관찰하였긴. hTATl은 L-[$^{14}$ C]tryp-tophan의 uptake를 유도하였으며, 그 uptake는 $Na^{+}$-과 Cl$^{-}$-비 의존적이었다. hTATl은 L-($^{14}$ C)tryptophan의 uptake를 시간의 존적으로 유도함을 알 수 있었다. hTATl에 의한 L-($^{14}$ C) tryptophan의 uptake는 방향족 아미노산인 phenylalanine, tyrosine 및 tryptophan에 의해서 억제되었으며 , hTATl에 의한 아미노산들의 uptake 실험에서 L-($^{14}$ C)phenylalanine, L-($^{14}$ C)tyrosine 및 L-($^{14}$ C)tryptophan의 수송을 확인하였다 hTATl에 의 한 L-($^{14}$ C)tryptophan의 uptake는 포화되었으며, Km치는 452.2$\pm$27.8 UM, V$_{max}$ 값은 2.1 $\pm$0.3 pmol/oocyte/min 이었다. L-($^{14}$ C)tyrosine 및 L-[$^{14}$ C]phenylalanine의 Km치는 각각 636.3$\pm$59.4 UM과 740.5$\pm$96.7 HM이었다. 실험용액의 pH 5.5에서 8.5까지의 변화는 hTATl에 의한 L-[$^{14}$ C]tfpto- phan의 uptake에 별다른 영향을 미치지 못하였다. hTATl의 CRNA를 미 세주입한 oocyte에서 배양시간 의존적 인 L-($^{14}$ C) tryptophan의 efflux를 볼 수 있었으며, 이 efflux는 oocyte 외 용액의 tryptophan존재 유무에는 영향을 받지 않았다. 따라서 본 연구의 결과로 hTATl이 상피세포로부터 혈류로의 방향족 아미노산의 수송에 중요한 역할을 할 것으로 사료된다.

• The Korean Journal of Physiology
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• 제27권2호
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• pp.227-232
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• 1993

The temperature dependence of $Na^+-dependent$ succinate uptake was studied in brush border (BBMV) and basolateral (BLMV) membrane vesicles isolated from the rabbit kidney cortex. The succinate uptake was markedly altered by temperature in a similar fashion in both membranes. The temperature dependence was characterized by a nonlinear Arrhenius plot with a break point at 22 and $25^{\circ}C$ for BBMV and BLMV, respectively. The activation energy was 3.91 and 17.09 kcal/mole at above and below the break point respectively, far BBMV; 2.65 and 14.05 kcal/mole, respectively, for BLMV. When temperature increased f개m 20 to $35^{\circ}C$, the Vmax of succinate transport increased from $3.49{\pm}0.11\;to\;5.90{\pm}0.86\;nmole/mg/5\;sec$ for BBMV and from $2.86{\pm}0.25\;to\;3.63{\pm}0.32\;nmole/mg/5\;sec$ for BLMV, with no change in Km in both membranes. These results suggest that renal dicarboxylate transport is similarly sensitive to a change in membrane physical state in BBMV and BLMV.

• Applied Microscopy
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• 제17권1호
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• pp.29-46
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• 1987

To study hexavalent chromium effects on mitochondrial electron transport, the activities of electron transport enzymes and conformational change of mitochondria treated with $40{\mu}M$ of sodium dichromate ($Na_{2}Cr_{2}O_{7}\;2H_{2}O$) were investigated. And so were those of liver mitochondria isolated from mouse intraperitoneally injected with sodium dichromate, 40mg per kg body weight. On both treatment with chromium(VI), the activities of electron transfer enzymes (Complex I and IV) were increased to some extent and the ultrastructural transformation of mitochondria from a condensed to an orthodox conformation was inhibited under State IV respiration. These results represent' inhibitory effect of hexavalent chromium on electron transport without inhibiting electron transfer enzymes (Complex I and IV) in mitochondria. On intraperitoneal treatment with hexavalent chromium as sodium dichromate and trivalent chromium as chromic chloride, containing 37.5 mg of chromium per kg body weight, respectively, the activities of electron transfer enzymes of liver isolated from mouse with chromium(VI) was reduced, but that with chromium(III) was not affected. And with chromium(VI), all mice after 12 hours of treatment died, only after 6 hours survived. With chromium(III), however, all survived. This indicates that hexavalent chromium is more toxic than trivalent chromiumin mouse liver.

• 한국의류학회지
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• 제14권3호
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• pp.229-240
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• 1990

The purpose of this study was to investigate the effect of hydrophilicity of the fiber on the water vapor transport properties of the fabric by using double layered fabrics of natural and synthetic fibers such as cotton, wool, nylon, dacron, orlon and polypropylene. Wickability and absorption rate were measured to determine the absorbancy of the fabrics. Dynamic and steady state water vapor transport properties were measured by cobaltous chloride method and evaporation method, respectively. Absorption was in the order of orlon> cotton > wool > nylon > polypropylene > dacron. Dynamic surface wetness of synthetic fabrics were faster than that of natural fabrics. For the double layered fabrics, higher water vapor transport was resulted when the natural fabric was exposed to lower vapor pressure and synthetic fabric was exposed to higher vapor pressure than when the fabrics were layered the other way around. Opposite result was obtained for orlon, which suggested that when the fabric of high absorbancy is exposed to the environment and lower absorbancy is to the skin, higher water vapor transpont could be resulted.

• Journal of Electrochemical Science and Technology
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• 제14권3호
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• pp.205-214
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• 2023

Soil salinity is becoming one of the most devastating environmental hazards over the years. Soil investigation involves fast, low cost and non disturbing methods to measure soil characteristics for both construction projects as well as for agricultural use. The electrical resistivity of saline soils is greatly governed by salt concentration and the presence of moisture in soil matrix. Experimental results of this investigation highlight that there is a significant relationship between the electrical resistivity of soil samples mixed with chloride solutions (NaCl, KCl, and MgCl₂) at various concentrations, and soil physical properties. Correlations represented by quadratic functions were obtained between electrical resistivity and soil characteristics, namely, water content, degree of saturation and salt concentration. This research reveals that the obtained correlations between electrical resistivity, salt concentration, water content and degree of saturation are effective for predicting the characteristics of salt affected soils in practice, which constitute a governing element in the assessment of saline lands sustaining infrastructure.

• The Korean Journal of Physiology and Pharmacology
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• 제3권5호
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• pp.529-538
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• 1999

This study was undertaken to examine the effect of ethanol on $Na^+ -dependent$ phosphate $(Na^+-P_i)$ uptake in opossum kidney (OK) cells, an established renal proximal tubular cell line. Ethanol inhibited ^Na^+-dependent$ component of phosphate uptake in a dose-dependent manner with $I_{50}$ of 8.4%, but it did not affect $Na^+-independent$ component. Similarly, ethanol inhibited $Na^+-dependent$ uptakes of glucose and amino acids (AIB, glycine, alanine, and leucine). Microsomal $Na^+-K^+-ATPase$ activity was not significantly altered when cells were treated with 8% ethanol. Kinetic analysis showed that ethanol increased $K_m$ without a change in $V_{max}$ of $Na^+-P_i$ uptake. Inhibitory effect of n-alcohols on $Na^+-P_i$ uptake was dependent on the length of the hydrocarbon chain, and it resulted from the binding of one molecule of alcohol, as indicated by the Hill coefficient (n) of 0.8-1.04. Catalase significantly prevented the inhibition, but superoxide dismutase and hydroxyl radical scavengers did not alter the ethanol effect. A potent antioxidant DPPD and iron chelators did not prevent the inhibition. Pyrazole, an inhibitor of alcohol dehydrogenase, did not attenuate ethanol-induced inhibition of $Na^+-P_i$ uptake, but it prevented ethanol-induced cell death. These results suggest that ethanol may inhibit $Na^+-P_i$ uptake through a direct action on the carrier protein, although the transport system is affected by alterations in the lipid environment of the membrane.

• 한국식품영양과학회지
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• 제34권9호
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• pp.1367-1374
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• 2005

사람의 정상 골모세포 FOB에서 아미노산 수송계 L의 발현 및 이들 수송계 L을 통한 아미노산 수송특성을 밝히기 위하여, FOB 세포에서 RT-PCR, western blot 분석 및 아미노산 uptake 실험 등을 수행하여 다음과 같은 결과들을 얻었다. FOB 세포에서 아미노산 수송계 L의 두 아형인 LAT1, LAT2및 그들의 보조인자 4F2hc의 발현을 확인할 수 있었다. FOB 세포에서 $_{L}-leucine$의 수송은 $Na^+$-비의존적이었다. FOB 세포에서 $_{L}-leucine$의 수송은 아미노산 수송계 L의 선택적 억제제인 BCH에 의해 완전히 차단되었다. FOB 세포에서 여러 아미노산들에 의한 L-leucine수송억제 실험결과는 Xenopus oocyte에서 시행되어 보고되어진 LAT1과 LAT2 수송억제 실험 결과의 특성을 모두 포함하였다. 본 연구의 결과로 사람의 정상 골모세포주인 FOB에서 는 세포성장 및 증식을 위한 중성 아미노산의 수송에 아미노산 수송계 L의 두 아형인 LAT1과 LAT2가 중요한 역할을 하고 있음을 확인할 수 있었다.

• Korean Journal of Acupuncture
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• 제23권1호
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• pp.45-57
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• 2006

Objective : This study was undertaker to determine if Juglandis Semen herbal acupuncture (JSA) exerts protective effect against alterations in membrane transport function in rabbits with mercury-induced acute renal failure. Methods : Nephrotoxicity was induced by subcutaneous administration of Hg(a single dose of 10mg/kg) and JSA was performed at both sides of Shenshu($(BL_{23})$, Sinsu) for 7 days. Results: The administration of Hg at a subcutaneous single dose of 10 mg/kg caused a reduction in GFR to 12% of the basal value and an increase in fractional $Na^+$ excretion to 8.9-fold, indicating generation of acute renal failure. When JSA were given for 7 days prior to Hg administration, such changes were significantly attenuated. The fractional excretion of glucose and phosphate was increased to approximately 102- and 35-fold, respectively, in rabbits treated with Hg alone. The increase in rabbits treated with Hg following ISA are significantly lower than that in animals treated with Hg alone. Uptakes of glucose and phosphate in purified isolated brush-border membrane and $Na^+-K^+-ATPase$ activity in microsomal fraction were inhibited in rabbits treated with Hg alone, suggesting that impairment in proximal reabsorption of glucose and phosphate is resulted from a direct damage of membrane transport carriers and disruption of the normal $Na^+$ gradient. Such changes were prevented by JSA. Conclusion These results indicate that the administration of Hg causes impairment in reabsorption of solutes in the proximal tubule via the generation of reactive oxygen species. JSA provides the protection against the Hg-induced impairment in proximal reabsorption, and its effect may be resulted from its antioxidant action.