• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.289-294
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• 2004

This study was carried out to investigate the antioxidative enzymes and isozymes between chilling-tolerant and -susceptible varieties at the booting stage under cold water stress $(13^{\circ}C)$ in japonica rice. Total SOD, CAT, POX, and GR activities on the basis of protein were found to be important factors to defend cold water stress. Especially, SOD and CAT activities showed distinctive differences between chilling-tolerant and -susceptible varieties. Chilling-tolerant varieties were higher than chilling-susceptible varieties for SOD and CAT activities. One of eight isozyme bands for SOD was a inducible isoform. Three isozymes for CAT and one isozyme for POX were closely correlated with defense to cold water stress. Total GR activities except Stejaree 45 on the basis fresh weight and POX were increased by cold water stress, but there was no difference between chilling-tolerant and -sus­ceptible varieties.

• Journal of Microbiology
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• v.38 no.1
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• pp.18-23
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• 2000

Streptomyces coelicolor produces three kinds of catalases to cope with oxidative stress and to allow normal differentiation. Catalase A is the major vegetative catalase which functions in removing hydrogen peroxide generated during the process of aerobic metabolism. To understand the regulatory mechanism of response against oxidative stress, hydrogen peroxide-resistant mutant (HR4O) was isolated from S. coelicolor J1501 following UV mutagenesis. The mutant overproduced catalase A more than 50-fo1d compared with the wild type. The mutation locus catRI was mapped closed to the mthB2 locus by genetic crossings. An ordered cosmid library of S. coelicolor encompassing the mthB2 locus was used to isolate the regulator gene (catR) which represses catalase overproduction when introduced into HR4O. A candidate catR gene was found to encode a Fur-like protein of 138 amino acids (15319 Da).

• Korean Journal of Plant Tissue Culture
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• v.26 no.1
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• pp.53-58
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• 1999

The gamma radiation-induced changes of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in callus cultures of cassava (Manihot esculenta Crantz) selected as a high yield of cell line for SOD were investigated. In normal cultures, the cell growth reached a maximum at 30 days after subculture (DAS), followed by a rapid decrease with further cultures. The SOD and POD specific activities (units/mg protein) showed the highest at the immediately after subculture and subsequently decreased to 20 DAS, and then increased to 30 DAS, whereas the CAT activity showed the lowest at just after subculture, and it continuously increased from 15 DAS to 30 DAS, showing a good correlation with the cell growth. Irradiation of gamma-ray of 50 and 70 Gy on 7 DAS inhibited significantly the cell growth by 50% and 80% at 14 days after treatment (DAT), respectively. In the cells irradiated with 70 Gy, SOD and POD specific activities increased by 4 and 2.5 folds at 14 DAT, respectively, whereas CAT activity was not affected. The results indicate that SOD and POD may be involved in the antioxidative mechanism in relation to oxidative stresses induced by subcultures and by gamma radiation in callus cultures of cassava.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.191-195
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• 2015

A 7-year-old castrated male Korean Shorthair cat was referred with lethargy and anorexia. Laboratory examination revealed moderate degenerative changes of peripheral neutrophils on blood smear examination and decreased levels of free and total thyroxine ($T_4$) as well as bacterial growth on blood culture. Molecular analyses of the 16S ribosomal RNA gene and heat shock protein 60 gene confirmed the bacterium as Enterobacter cloacae. A minimal inhibitory concentration test showed multidrug resistance of the bacterium against 16 antibiotics. Polymerase chain reaction (PCR) and subsequent sequencing specifically for $bla_{TEM}$, $bla_{SHV}$, $bla_{CTX-M}$, and plasmid-mediated ampC genes revealed positive results to $bla_{TEM-1}$, $bla_{CTX-M-15}$, and plasmid-mediated $bla_{ACT-1}$ genes, indicating that the isolated bacterium contains plasmids containing genes encoding extended-spectrum beta-lactamase and plasmid-mediated ampC beta-lactamase. After 1 month of treatment with antibiotics and levothyroxine, the cat's condition improved; both the thyroid function test and the blood culture showed no abnormalities. This is the first report of community-acquired multidrug-resistant E. cloacae-induced euthyroid sick syndrome in a cat. By the prompt diagnostic procedures and properly selected antibiotic therapy, the cat was recovered from the multidrug-resistant bacterium-induced septicaemia.

• Journal of dental hygiene science
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• v.6 no.1
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• pp.1-9
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• 2006

Cathepsin K (cat K) is the major cysteine protease expressed in osteoclasts and was thought to play a key role in matrix degradation during bone resorption. It was shown that the intracellular maturation of cat K was prevented by the cAMP antagonist, Rp-cAMP, and the protein kinase A (PKA) inhibitors of KT5720 and H89. In contrast, forskolin, a adenylate cyclase agonist, rather induced Cat K processing and maturation in osteoclasts. Furthermore, to determine whether cat K processing and maturation signaling involves protein kinase C (PKC), mouse total bone cells were treated with calphostin C, a specific inhibitor of PKC, however, no effect was observed, indicating that calphostin C did not affect to osteoclast-mediated cat K processing and maturation. Thus, it is indicated that the cAMP-PKA signaling pathway regulates cat K maturation in osteoclasts. Since secreted proenzymes have the potential to reenter the cell via M6P receptor, to prevent this possibility, it was tested cAMP antagonist Rp-cAMP and the PKA inhibitors KT5720 and H89 in the absence or presence of M6P. Inhibition of cat K processing by Rp-cAMP, KT5720, or H89 was observed in a dose-dependent manner. Furthermore, the addition of M6P resulted in enhanced potency of Rp-cAMP, KT5720 and H89. These dose-dependently inhibited in vitro bone resorption with a potency similar to that observed for inhibition of cat K processing.

• Journal of Life Science
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• v.20 no.10
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• pp.1483-1489
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• 2010

The purpose of this study was to investigate the effects of treadmill exercise and a protein diet on immunoglobulin and antioxidant enzymes in rats. Forty-four male Sprague-Dawley rats, 5 weeks old, were used. Experimental groups were divided into exercise with protein diet group (A, n=11), exercise group (B, n=11), protein diet group (C, n=11), and the control group (D, n=11). Exercise was administered through a treadmill running program (14~18 m/min, $0^{\circ}$ grade, 20 min/day, 5 day/wk) and these rats were given a 40% protein diet for 4 wk. The results of this study are as follows: the protein diet group showed a significant increase in IgG of immunoglobulin compared to the exercise group and control group; the exercise with protein diet group and protein diet group showed a significant increase in SOD activity of antioxidant enzymes compared to the control group; the exercise with protein diet group, exercise group and protein diet group showed a significant increase in GPx activity of antioxidant enzymes compared to the control group; the exercise with protein diet group showed a significant increase in CAT activity of antioxidant enzymes compared to the protein diet group and control group. In conclusion, treadmill exercise and a protein diet were found to help with immunoglobulin and antioxidant enzymes. Further research regarding the effects of exercise and protein diets is required.

• Microbiology and Biotechnology Letters
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• v.26 no.6
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• pp.566-568
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• 1998

Partial nucleotide sequence (nt 1-1842) of chloramphenicol resistance plasmid pKH7 has been reported previously and residual nucleotide sequence (nt 1843-4118) of pKH7 was determined and then the complete nucleotide sequence of pKH7 was obtained. pKH7 consists of 4118 bp and has three ORFs. Besides Rep and CAT proteins described in previous paper, Pre protein which mediates site-specific recombination in Staphylococcus aureus was found to be on pKH7. R $S_{A}$, a site-specific recombination site of Pre protein, and palA, a specific lagging-strand conversion signal, was also found in pKH7. Amino acid sequence of Pre protein of pKH7 was compared with those of other antibiotic resistant Staphylococcus aureus plasmids.s.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.546-552
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• 2018

A comprehensive collection of proteins senses local changes in intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) and transduces these signals into responses to agonists. In the present study, we examined the effect of sphingosine-1-phosphate (S1P) on modulation of intracellular $Ca^{2+}$ concentrations in cat esophageal smooth muscle cells. To measure $[Ca^{2+}]_i$ levels in cat esophageal smooth muscle cells, we used a fluorescence microscopy with the Fura-2 loading method. S1P produced a concentration-dependent increase in $[Ca^{2+}]_i$ in the cells. Pretreatment with EGTA, an extracellular $Ca^{2+}$ chelator, decreased the S1P-induced increase in $[Ca^{2+}]_i$, and an L-type $Ca^{2+}$-channel blocker, nimodipine, decreased the effect of S1P. This indicates that $Ca^{2+}$ influx may be required for muscle contraction by S1P. When stimulated with thapsigargin, an intracellular calcium chelator, or 2-Aminoethoxydiphenyl borate (2-APB), an $InsP_3$ receptor blocker, the S1P-evoked increase in $[Ca^{2+}]_i$ was significantly decreased. Treatment with pertussis toxin (PTX), an inhibitor of $G_i$-protein, suppressed the increase in $[Ca^{2+}]_i$ evoked by S1P. These results suggest that the S1P-induced increase in $[Ca^{2+}]_i$ in cat esophageal smooth muscle cells occurs upon the activation of phospholipase C and subsequent release of $Ca^{2+}$ from the $InsP_3$-sensitive $Ca^{2+}$ pool in the sarcoplasmic reticulum. These results suggest that S1P utilized extracellular $Ca^{2+}$ via the L type $Ca^{2+}$ channel, which was dependent on activation of the $S1P_4$ receptor coupled to PTX-sensitive $G_i$ protein, via phospholipase C-mediated $Ca^{2+}$ release from the $InsP_3$-sensitive $Ca^{2+}$ pool in cat esophageal smooth muscle cells.

• Journal of Nutrition and Health
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• v.39 no.5
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• pp.476-484
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• 2006

To elucidate the relationship between blood parameters related bone metabolism and antioxidant enzyme activity in postmenopausal period 60 women residing in Iksan area were recruited. Food and nutrient intake of each individual subject were estimated by 24-hour recalls of 3 non-consecutive days. The biochemical markers including total protein, albumin, osteocalcin (intact bone gla protein; BOP), calcium, phosphorus and hemoglobin were measured in fasting blood. In addition, parameters of antioxidative capacity including the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) , catalase (CAT) and total antioxidant capacity (TA) were monitored in blood, also. The mean age, height, weight, and BM! of subjects were 64.8 years, 151.1 em, 59.5 kg $26.0\;kg/m^2$, respectively. The mean SOD, GPx, and CAT activities were 138.5 U/ml, 1,273.8 U/ml and 314.3 kU/l respectively, and TA was 1.16 mmol/l without significant difference among different age groups. BMI was positively correlated with SOD activity (p < 0.01). SOD activity and CAT activity showed positive correlation with serum albumin (p < 0.05) and hemoglobin (p < 0.01). In conclusion, this study revealed that antioxidant enzyme activity holds a significant relationship with the blood parameters like as serum albumin and hemoglobin in postmenopausal women and further systematic research is needed to investigate the their relation mechanism.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.5
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• pp.393-400
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• 2009

NO released by myenteric neurons controls the off contraction induced by electrical field stimulation (EFS) in distal esophageal smooth muscle, but in the presence of nitric oxide synthase (NOS) inhibitor, L-NAME, contraction by EFS occurs at the same time. The authors investigated the intracellular signaling pathways related with G protein and ionic channel EFS-induced contraction using cat esophageal muscles. EFS-induced contractions were significantly suppressed by tetrodotoxin ($1\;{\mu}M$) and atropine ($1\;{\mu}M$). Furthermore, nimodipine inhibited both on and off contractions by EFS in a concentration dependent meaner. The characteristics of 'on' and 'off contraction and the effects of G-proteins, phospholipase, and $K^+$ channel on EFS-induced contraction in smooth muscle were also investigated. Pertussis toxin (PTX, a $G_i$ inactivator) attenuated both EFS-induced contractions. Cholera toxin (CTX, $G_s$ inactivator) also decreased the amplitudes of EFS-induced off and on contractions. However, phospholipase inhibitors did not affect these contractions. Pinacidil (a $K^+$ channel opener) decreased these contractions, and tetraethylammonium (TEA, ${K^+}_{Ca}$ channel blocker) increased them. These results suggest that EFS-induced on and off contractions can be mediated by the activations Gi or Gs proteins, and that L-type $Ca^{2+}$ channel may be activated by G-protein ${\alpha}$ subunits. Furthermore, ${K^+}_{Ca^-}$ channel involve in the depolarization of esophageal smooth muscle. Further studies are required to characterize the physiological regulation of $Ca^{2+}$ channel and to investigate the effects of other $K^+$ channels on EFS-induced on and off contractions.