• The Korean Journal of Physiology
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• v.30 no.2
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• pp.279-288
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• 1996

Chronic exposure to cadmium impairs various renal tubular functions, including organic acid (anion) secretion. To investigate the mechanism of cadmium-induced alterations in the organic anion transport system, kinetics of p-aminohippurate (PAH) uptake was studied in renal cortical basolateral membrane vesicles (BLMV) isolated from cadmium-intoxicated rats (adult male Sprague-Dawley). Cadmium intoxication was induced by subcutaneous injections of $CdCl_{2}$ (2 mg Cd/kg per day) for 3 weeks. The renal plasma membrane vesicles were prepared by Percoll gradient centrifugation. The vesicular uptake of $^{14}C$-PAH was determined by rapid filtration technique using Millipore filter. Cadmium intoxication resulted in a marked attenuation of $Na^{+}$-dependent, ${\alpha}$-ketoglutarate (${\alpha}$KG)-driven PAH uptake with no changes in $Na^{+}$ and ${\alpha}$KG-independent transport component. Kinetic analysis indicated that Vmax, but not Km, of the $Na^{+}$-dependent, ${\alpha}$KG-driven component was reduced. A similar reduction of $Na^{+}$-dependent, ${\alpha}$KG-driven PAH uptake was observed in normal membrane vesicles directly exposed to inorganic cadmium in vitro, and this was accompanied by an inhibition of both $Na^{+}$-dependent ${\alpha}$KG uptake and ${\alpha}$KG-PAH exchange activity. These results indicate that during chronic exposure to cadmium, free cadmium ions liberated in the proximal tubular cytoplasm directly interact with the basolateral membrane and impair the active transport capacity for organic anions, most likely due to an inhibition of both $Na^{+}$-dicarboxylate cotransporter and dicarboxylate-organic anion antiporter activities.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.346-349
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• 2004

Black colored rice has long been consumed in Oriental countries and is considered to be a healthy food. Extracts from rice with three different colors (white, black, and green) were prepared by using 80% MeOH and subjected to biological screening activities. The levels of antioxidative activity of black colored rice cultivars such as C3GHi and Heugjinjubyeo in radical scavenging activity were higher than those of the related white and green rice ones. When the effect of the extracts on thrombin time inhibition was analyzed, the extract from Heugjinjubyeo showed a dose-dependent suppressive activity. In addition, all the extracts tested did not inhibit the cyclooxygenase activity. Therefore the health benefits of the colored rice are attributed in part to their unique phytochemical composition such as high level of anthocyanin pigments with other minor strong antioxidant components for potential use in neutraceutical or functional food formulations.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.2
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• pp.80-88
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• 1997

Malignant tumors of extremeties involving major neurovascular structures have been treated by amputation. However recent development of diagnostic tools(CT, MRI etc.), surgical techniques, anticancer chemotherapeutic agents, and radiation techniques allow surgeons to treat malignant tumors in the limb without amputation. It has been reported that a local application of low-heat to the tissue with tumor can kill tumor cells. It is, however, not known if the attendant neural and vascular injuries may be recovered. The present study was, therefore, undertakn to address this question in rabbit sciatic nerves. A low-heat injury to the sciatic nerve was induced by perfusing the nerve with $60^{\circ}C$ saline for 30 minutes and the courses of functional and morphological recovery of the nerve were evaluated for 16 weeks. The results are summerized as follows : 1. In the electromyographic nerve conduction test the average amplitude was markedly attenuated at 4 and 8 weeks after the low-heat treatment, but it progressively increased to the level 89.5% of the control at 16 week post-treatment. The average latency in the control group was 0.62 msec. The latency in the experimental group was much longer than this at 4 and 8 week post-treatment, but it progressively reverted to the control level, showing 0.622 msec at 16 weeks. 2. In the needle EMG, many fibrillation potentials and positive sharp waves were appeared until 8 weeks post-treatment. After 16 weeks, however, no fibrillation potential was observed. 3. In the early phase of post-treatment period, the myelinated nerve fibers contained many vacuoles and the number of myelinated nerve fibers appeared to be considerably reduced. However, as time goes myelinated nerve fibers were regenerated, such that after 16 weeks the histologic appearance of the nerve was similar to that of the control group.