• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.818-825
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• 2013

We isolated and functionally characterized the ${\alpha}$- and ${\beta}$-subunits (ApCpnA and ApCpnB) of a chaperonin from Aeropyrum pernix K1. The constructed vectors pET3d-ApCpnA and pET21a-ApCpnB were transformed into E. coli Rosetta (DE3), BL21 (DE3), or CodonPlus (DE3) cells. The expression of ApCpnA (60.7 kDa) and ApCpnB (61.2 kDa) was confirmed by SDS-PAGE analysis. Recombinant ApCpnA and ApCpnB were purified by heat-shock treatment and anion-exchange chromatography. ApCpnA and ApCpnB were able to hydrolyze not only ATP, but also CTP, GTP, and UTP, albeit with different efficacies. Purified ApCpnA and ApCpnB showed the highest ATPase, CTPase, UTPase, and GTPase activities at $80^{\circ}C$. Furthermore, the addition of ApCpnA and ApCpnB effectively protected citrate synthase (CS) and alcohol dehydrogenase (ADH) from thermal aggregation and inactivation at $43^{\circ}C$ and $50^{\circ}C$, respectively. In particular, the addition of ATP or CTP to ApCpnA and ApCpnB resulted in the most effective prevention of thermal aggregation and inactivation of CS and ADH. The ATPase activity of the two chaperonin subunits was dependent on the salt concentration. Among the ions we examined, potassium ions were the most effective at enhancing the ATP hydrolysis activity of ApCpnA and ApCpnB.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.1
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• pp.24-30
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• 2005

The flow of saliva is controlled entirely by nervous stimuli. The present study was aimed to explore the role of sympathetic and parasympathetic nerves in the regulation of sodium transporters and water channels in the salivary gland. Rats were denervated of their sympathetic and parasympathetic nerves to the submandibular gland, and the expression of sodium transporters and water channels was determined. The expression of either ${\alpha}-1$ or ${\beta}-1$ subunit of Na, K-ATPase was not significantly affected by the sympathetic denervation. On the contrary, the expression of both subunits was decreased by the parasympathetic denervation. The expression of ${\alpha}-,\;{\beta}-$, and ${\gamma}$-subunits of ENaC was not significantly affected by the sympathetic denervation, but was increased by the parasympathetic denervation. On the contrary, the expression of NHE3 was markedly decreased by both the sympathetic and the parasympathetic denervation. The sympathetic denervation significantly increased the expression of AQP1, while the parasympathetic denervation was without effect. The sympathetic and parasympathetic denervation significantly increased the expression of AQP4. The sympathetic denervation did not affect the expression of AQP5, but the parasympathetic denervation significantly decreased it. These results suggest that sympathetic and parasympathetic nerves have tonic effects on the regulation of sodium transporters and AQP water channels in the salivary gland. The sympathetic and parasympathetic denervation may then result in alterations of secretory rate and electrolyte composition of the saliva.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.4
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• pp.223-230
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• 2005

The purpose of the present study was to examine the effect of naltrexone, an opioid antagonist, on secretion of catecholamines (CA) evoked by cholinergic nicotinic stimulation and membrane-depolarization from the isolated perfused rat adrenal gland and to establish the mechanism of its action. Naltrexone $(3{\times}10^{-6}M)$ perfused into an adrenal vein for 60 min produced time-dependent inhibition in CA secretory responses evoked by ACh $(5.32{\times}10^{-3}M)$ , high $K^+$ $(5.6{\times}10^{-2}M)$ , DMPP ($10^{-4}$ M) and McN-A-343 $(10^{-4}M)$ . Naltrexone itself did also fail to affect basal CA output. In adrenal glands loaded with naltrexone $(3{\times}10^{-6}M)$ , the CA secretory responses evoked by Bay-K-8644, an activator of L-type $Ca^{2+}$ channels and cyclopiazonic acid, an inhibitor of cytoplasmic $Ca^{2+}-ATPase$, were also inhibited. However, in the presence of met-enkephalin $(5{\times}10^{-6}M)$ , a well-known opioid agonist, the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were also significantly inhibited. Collectively, these experimental results demonstrate that naltrexone inhibits greatly CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as that by membrane depolarization. It seems that this inhibitory effect of naltrexone does not involve opioid receptors, but might be mediated by blocking both the calcium influx into the rat adrenal medullary chromaffin cells and the uptake of $Ca^{2+}$ into the cytoplasmic calcium store, which are at least partly relevant to the direct interaction with the nicotinic receptor itself.

• Journal of Life Science
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• v.10 no.1
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• pp.40-44
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• 2000

The SNF2/SW ATPase/helicase family comprises proteins form a variety of species with in vivo functions, such as transcriptional regulation, maintenance of chromosome stability during mitosis, and various types of DNA repair. Here, we reported the characterization of h게2+gene which was iolated by PCR amplification using the conserved domain of SNF2 motifs. Sequence analysis of PCR product showed striking evolutionary conservation among the SNF2 family of proteins. Two transcripts of 6.7 and 3.4 Lb were detected by Northern blot analysis. furthermore, the intensities of these two bands were increased by ultraviolet(UV) irradiation. These results indicate that the hrp2+ is a novel member of the SNF2 family of proteins and is one of the UV-inducible genes in S. pombe. To determine the level of transcripts of hrp2+ gene during cellular growth, Northern blot analysis were performed. This result indicates that the level of hrp2+transcript reached its maximum before cells entered the exponential growth phase. This suggests that hrp2+ gene is experssed mainly at the early stage of cell growth.

• The Korean Journal of Ecology
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• v.6 no.4
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• pp.243-249
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• 1983

Absorption pattern of potassium, calcium, phosphate and nitrate ions, and the pH change during ion-absorption at pH 3.0-11.0 by Oryza sativa L. were studied to investigate indirectly the evidence of H^+-efflux by ATPase. The rice seedlings which were grown either in $L^{\circ} -dark or in L^+-sunlight$, were used both in each ion-absorption to compare with one another. The uptake rate of these ions appeared to favor more in $L^+than in L^{\circ}$, over all range in pH, nearly with the same pattern. The absorption of potassium resulted in bell shape and that of calcium increased linearly to the alkali range. The shape of phosphate-absorption showed nearly the t-distribution curve with high value in acid range and the uptake of nitrate resulted in the dual peaks, but higher in acid range. The pH of the external solution changed from the range of 3.5-11.0 to 3.5-7.0 after lhr-absorptioin, and further acidified after 3hr-absorption. It is suggested that the pH change of the external solution be affected by $ H^+-efflux$ which may be caused by the ATP-hydrolysis.

• Environmental Analysis Health and Toxicology
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• v.7 no.1_2
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• pp.17-34
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• 1992

The object of this study is to investigate the toxicity of S-biol (d-allethron-d-transchrysanthemate) and the mode of action between other synthetic pyrethroid insecticides and S-biol in rats. Rats were treated daily with S-biol (25 mg/kg, 50 mg/kg, 100mg/kg) by oral administration for 5 weeks. The experimental results were summerized as follows: Biochemical parameters such as LDH and Glucose in serum were much more increased in control groups. No significant hematological change excepts for MCHC in rats treated with S-biol 100 mg/kg were observed in all groups compared to control groups. In animals treated with S-biol for 4∼5 weeks, the levels of cytochrome P-450 in the liver were significantly increased. In renal microsomal fractions, however, no significant changes of cytochrome P-450 contents were observed. The activitis of ATPase in groups treated with S-biol (50 mg/kg, 100 mg/kg) were decreased compared to those in other groups. TBA values and activities of glucose-6-phosphatase in the liver were increased a little in the groups treated with S-biol (100 mg/kg) for 5 weeks. The activities of cholinesterase in hepatic and serum were not significantly changed in all groups but slightly decreased in animals treated with high dose of S-biol (100 mg/kg). The activities of carboxylesterase in serum and in the liver were slightly increased but not significantly changed.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.700-704
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• 2004

Chinese-style pork jerky is a typical intermediate moisture meat product obtained by curing, drying and roasting pork samples. The chemical, physical and microbiological characteristics of pork jerky were evaluated throughout processing. The moisture content varied from 72.5% to 23.4 or 19.6% and aw varied form 0.97 to 0.74 or 0.72 in accordance with processing steps. The pork jerky roasted at $200^{\circ}C$ had higher shear value than roasted at $150^{\circ}C$ because the moisture content and aw of the former sample was lower than the later sample. The nitrite losses during whole processing steps amount to nearly 50%. The TBA value of pork jerky varied from 0.34 to 9.25 or 9.83 mg of malonaldehyde depended on processing steps. The VBN value of pork jerky ranging from 0.25 to 22.4 or 23.5 mg/kg depended upon processing steps. The ATPase activity of myofibrillar proteins during processing steps were partly or entirely denatured by the heat-drying or heat-roasting treatment. A gradual decrease in microorganism count during processing of pork jerky was also observed.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.184-184
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• 1998

Aldose reductase(AR), a rate-limiting enzyme in the polyol pathway, has been demonstrated to cause the intracellular accumulation of sorbitol or galactitol and hence to play key roles not only in the cataract formation in the lens but also in the pathogenesis of diabetic complications such as neuropathy, retinopathy and nephropathy, etc. In a series of investigations to evaluate potential AR inhibitors from medicinal plants, we have shown that some hot water extracts exhibited a significant inhibition of a significant inhibition of bovine lens AR in vitro. Among active plants, the roots of Angelica dahuria (Umbelliferae) were shown to have relatively potent AR inhibitory activity. Systematic fractionation of the ether soluble fraction monitored by bioassay led to isolation of two furanocoumarins, byakangelicin(I) and ter-O-methyl byakangelicin( II), were identified as potential AR inhibitors, their $IC_{50}$ values being 6.2 M and 2.8 M, respectively.

• Applied Microscopy
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• v.22 no.1
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• pp.113-127
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• 1992

The present study was investigated to elucidate the effects of chlorambucil the heart tissue of various-aged rats. The male rats ranging from 3 to 36 months were used. The cytochemical and biochemical changes in myocardium of the rats were studied in the aspect of free radical roles in aging process. With the goals of evaluating the potential roles of free radicals in aging process, evidence was shought for alterations of myocardial lipid peroxide levels in control and chlorambucil treated rats. The result are summarized as follows: 1. Cytochemical studies showed that the activities of $Mg^{++}$-ATPase and succinic dehydrogenase increased with age. However, these enzyme activities were decreased with treatment of chlorambucil, when compared with control group. Interestingly it was observed that chlorambucil treatment increased the activity of acid phosphatase from 6 months upto 18 months, and decreased after 18 months. 2. The lipid peroxide level in myocatdium was increased with age; chlorambucil-treated group was higher than that of control group. 3. Age-dependent increase in activities of monoamine oxidase, xanthine oxidase and catalase was observed. But the increase of catalase activity was higher than that of monoamine oxidase and xanthine oxidase activity in control group. However, in chlorambucil-treated group, age-dependent decrease of these enzyme activities was observed, and catalase activity was more significant particularly with regard to other enzymes. In consequently, the morphological alterationsof myocardium due to chlorambucil treatment was exclusively observed. We demonstrate that this alteration is occured by lipid peroxidation upon chlorambucil treatment.

• Journal of Food Hygiene and Safety
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• v.8 no.4
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• pp.195-204
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• 1993

Basolateral and brush border membrane (BLM and BBM) vesicles of renal proximal tubules were prepared from adult male New Zealand White rabbits to evaluate as a potential model for assessment of nephrotoxicity. PAH uptakes using BLMV, glucose and leucine uptakes using BBMV were measured in the rabbits treated cephaloridine. In addition, urinalysis and histopathological studies were performed to investigate the correlationship with membrane vesicle uptakes. The results were as follows: (1) the activite of Na+, K+ -ATPase was enriched 12.3-fold in vasolateral memvrane vesicles (BLMV) and the specific activity of alkaline phosphatase in purified brush border memvrane vesicles (BBMV) was enriched 10.1-fold compared with each of microsomal homogenate. (2) In the uptake experiments, cephaloridine decreased initial and probenecid-sensitive PAH uptakes in BLMV. (3) Cephaloridine tested decreased initial and phlorizin-sensitive glucose uptakes in BBMV. (4) Cephaloridine tested decreased initial and Na+-dependent leucine uptakes in BBMV. (5) Cephaloridine tested significantly increased the urinary excretion of glucose and activity of ${\gamma}$-GTP. (6) Cephaloridine tested caused moderate necrotic changes in renal tubular cells and formation of urinary cast in the lumina of Henle's loop and collecting tubules besides the swelling of renal tubules.