• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.661-670
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• 1998

Dopamine has been generally known to exert antinociceptive action in behavioral pain test, such as tail flick and hot plate test, but there appears to be a great variance in the reports on the antinociceptive effect of dopamine depending on the dosage and route of drug administration and type of animal preparation. In the present study, the effects of dopamine on the responses of wide dynamic range (WDR) cells to mechanical, thermal and graded electrical stimuli were investigated, and the dopamine-induced changes in WDR cell responses were compared between animals with an intact spinal cord and the spinal animals. Spinal application of dopamine (1.3 & 2.6 mM) produced a dose-dependent inhibiton of WDR cell responses to afferent inputs, the pinch-induced or the C-fiber evoked responses being more strongly depressed than the brush-induced or the A-fiber evoked responses. The dopamine-induced inhibition was more pronounced in the spinal cat than in the cat with intact spinal cord. The responses of WDR cell to thermal stimulation were also strongly inhibited. Dopamine $D_2$ receptor antagonist, sulpiride, but not $D_1$ receptor antagonist, significantly blocked the inhibitory action of dopamine on the C-fiber and thermal responses of dorsal horn cells. These findings suggest that dopamine strongly suppresses the responses of WDR cells to afferent signals mainly through spinal dopamine $D_2$ receptors and that spinal dopaminergic processes are under the tonic inhibitory action of the descending supraspinal pathways.

• BMB Reports
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• v.36 no.2
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• pp.196-200
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• 2003

Previously, we reported the biochemical properties of RGA1 that is expressed in Escherichia coli (Seo et al., 1997). The activities of RGA1 that hydrolyzes and binds guanine nucleotide were dependent on the $MgCl_2$ concentration. The steady state rate constant ($k_{cat}$) for GTP hydrolysis of RGA1 at 2 mM $MgCl_2$ was $0.0075{\pm}0.0001\;min^{-1}$. Here, we examined the effects of pH and cations on the GTPase activity. The optimum pH at 2 mM $MgCl_2$ was approximately 6.0; whereas, the pH at 2 mM $NH_4Cl$ was approximately 4.0. The result from the cation dependence on the GTPase (guanosine 5'-triphosphatase) activity of RGA1 under the same condition showed that the GTP hydrolysis rate ($k_{cat}=0.0353\;min^{-1}$) under the condition of 2mM $NH_4Cl$ at pH 4.0 was the highest. It corresponded to about 3.24-fold of the $k_{cat}$ value of $0.0109\;min^{-1}$ in the presence of 2 mM $MgCl_2$ at pH 6.0.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.791-796
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• 2014

Cryopreservation of epididymal sperm is an effective technique to preserve genetic materials of domestic cats and wild felids when they unexpectedly die. However, this technique inevitably causes detrimental changes of cryopreserved-thawed spermatozoa, for example, by physical damage and excessive oxidative stress. L-carnitine is an antioxidant that has been used to improve sperm motility in humans and domestic animals. This study aimed to investigate the effects of L-carnitine on cat epididymal sperm quality following cryopreservation and thawing. After routine castration, cauda epididymides were collected from 60 cat testes. The epididymal spermatozoa from 3 cauda epididymides were pooled as 1 replicate. Spermatozoa samples (16 replicates) were examined for spermatozoa quality and then randomly divided into 4 groups: 0 mM L-carnitine (control), 12.5 mM, 25 mM and 50 mM L-carnitine. The sperm aliquots were then equilibrated and conventionally frozen. After thawing, sperm motility, plasma membrane integrity, DNA integrity and acrosome integrity were evaluated. The 25 mM L-carnitine significantly improved sperm motility compared with a control group (p<0.05), although this was not significantly different among other concentrations. In conclusion, supplementation of 25 mM L-carnitine in freezing extender improves cauda epididymal spermatozoa motility. The effects of L-carnitine on the levels of oxidative stress during freezing and thawing remains to be examined.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.789-795
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• 2004

A promoter-probe shuttle vector pSK1Cat was constructed for the isolation of transcriptional signal sequences from Corynebacterium glutamicum. Besides conferring resistance to kanamycin in Escherichia coli and C. glutamicum, the vector carried a promoterless cat gene to confer resistance to chloramphenicol upon insertion of the appropriate transcriptional signals in the multiple cloning site. By utilizing the vector, a series of transcriptionally active fragments were isolated from the genome of C. glutamicum. The clones, ranging from 200 bp to 1 kb in size, were grouped into 3 classes of strong, medium, and weak, based on the chloramphenicol acetyltransferase (CAT) activity and sensitivity to the chloramphenicol of the clone-carrying C. glutamicum cells. C. glutamicum cells carrying the $P_{19}$ clone, a representative in the strong class, were able to grow on minimal agar plates containing over $40 mg/mell$ chloramphenicol, and showed CAT activity of 10 m㏖/mgㆍmin, performing slightly better than the cells carrying $P_{tac}$ , a strong E. coli promoter. Subcloning analysis of the $P_{19}$ clone identified a 180 bp intergenic fragment ($P_{180}$), which was located upstream of a gene encoding a hypothetical membrane protein. The expression conferred by $P_{180}$ was not affected by either the kinds of carbon sources or changes in temperature. These properties make the $P_{180}$ clone useful for the deregulated expression of biosynthetic genes in C. glutamicum during amino acid fermentation.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.95-95
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• 1995

뇌신경 변성 / 퇴행과 관련된 중요한 병인론 중의 하나는 변성 과정에서 형성된 유리기(free radical)로 인한 항산화계의 평형 소실로 알려져 있다. Aspalatone (APT)의 예상되는 항산화 효능을 검정하기 위하여 본 실험에서는 Kainic acid (KA) 유발 뇌변성 모델을 적용하였다. KA 모델은 변연계의 간질성 경련과 신경세포 변성에 대하여 재현성 있는 병변 모델을 제공해 주며, 이와 같은 신경세포의 병독 기전에 산소 유리기가 관여함이 강력히 시사되고 있기 때문이다. KA 투여로 인하여 지속적이고도 전형적인 간질성 경련이 관찰되고 1일 이내에 높은 치사율을 보였으나 APT으로 인하여 그 간질성 경련 행위와 비율이 억제되고 KA 유발 치사율도 억제되었다. 최종 KA 투여 3일 후에 얻어진 흰쥐 해마 및 대뇌 피질에서 항산화 효소인 Superoxide dismutase (SOD), Catalase (Cat.), Glutathione peroxidase (GSH-PX) 및 과산화지질의 지표인 Malondialdehyde (MDA)를 검정하였다. 대조군에 비하여 KA는 뇌조직의 SOD-1을 유도하였으나, Cat.와 GSH-PX의 활성은 현저히 유도되지 않았고, 반면에 MDA 치는 현저히 증가하였다. 즉, Cat., GSH-PX와 같은 $H_2O$$_2$중화제가 동반 유도하지 않는 SOD의 유도는 세포내 축적되는 $H_2O$$_2$로 인하여 Fenton/Haber-Weiss 반응을 가속화하여 과산화지질화를 촉진함을 시사한다. APT 병용 투여로 SOD는 현저히 유도되지 않았으나 특히 Cat.가 현저히 유도되어지고 MDA는 억제되었다. 이와 같은 생화학적인 결과는 다음의 형태학적인 소견과 일치한다. Fos 관련 항원 (FRA)와 SOD-1을 면역세포화학 (Immunocytochemistry)적 방법으로 이중 표식 (double-labelling) 하였다. FRA는 KA로 인한 신경세포의 자극에 대한 지표로 응용하였고, SOD-1은 퇴행성 뇌질환에서 산화적 손상의 지표로 사용하였다. KA 투여로 해마의 dentate gyrus (DG) 내에 강한 면역환성 (immunoreactivity)이 나타났고 pyramidal cell layer (PCL)와 glia에 SOD-1이 강하게 염색되었다. APT 병용 투여로 상당수의 경련이 일어나지 않은 흰쥐는 해마의 DG에 FRA가 경미하게 염색되었고, PCL에 SOD-1도 경미하게 나타났으나, 경련이 나타난 쥐에서는 KA만을 투여한 흰쥐와 구별되지 않았다. 이상의 APT의 항산화 효과는 KA로 인한 뇌세포 변성 개선에 중요한 인자로 작용할 것으로 사료되나, 보다 명확한 APT의 기전을 검색하고 직접 임상에 응응하기 위하여는 보다 다양한 실험 조건이 보완되어야 찰 것으로 생각된다.

• The Korean Journal of Physiology
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• v.14 no.2
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• pp.21-28
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• 1980

In order to investigate the effect of cholinergic substance on the electrical and the mechanical activities of the stomach muscle, 10 isolated cat stomachs were studied. At various sites of a stomach muscle preparation, the electrical activity was monopolarly recorded by using capillary electrodes containing chlorided silver wires, and the isometric contractile activity was recorded simultaneously at the terminal portion of the antrum in Krebs solution$(36^{\circ}C)$ which was aerated with a gas mixture consisting of 95% $O_2$ and 5% $CO_2$. The recording of these activities were performed before (control period) and after acetylcholine$(10^{-5}M)$ and atropine $(10^{-6}M)$ administrations serially. Following results were obtained: 1) The mean frequency of the slow wave was $4.36{\pm}0.22\;cycles/min$ at all the various sites of the cat stomach. The slow wave was propagated caudad in sequence and its velosity of propagation increased as the slow wave approached the pylorus in normal Krebs solution. 2) After acetylcholine administration, the frequency of the slow wave increased transiently and the increase of slow wave frequency was followed by the isometric contraction of antral muscle in association with the second potential which succeeded the slow wave. 3) By atropine administration, the stimulatory effect of acetylcholine on the antral muscle contraction was abolished completely, and the frequency of the slow wave decreased significantly compared with that of the control period, which tendency was more prominent in the antrum. The above results suggest that the transient increase in the frequency of gastric slow wave by acetylcholine may have some influence upon the contraction mechanism of the cat antral muscle.

• Journal of Veterinary Clinics
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• v.37 no.4
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• pp.208-212
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• 2020

A 6-year-old castrated male Russian Blue cat was presented for evaluation of dyschezia. Abdominal ultrasound revealed hyperechoic nodules in both kidneys, heterogeneous mass in abdomen, and extensive mesenteric thickening with multiple hypoechoic nodules. Computed tomography showed multiple hypodense lesions in both kidneys and diffuse nodular infiltration around the mesentery. Fine needle aspirates (FNA) acquired under ultrasound guidance from the mesentery consisted of large lymphocytes which have round to irregular nuclei with granular chromatin, prominent nucleoli and a small amount of basophilic cytoplasm. Polymerase chain reaction (PCR) for antigen receptor gene rearrangement result of FNA sample revealed a T-cell malignancy. The cat died from acute renal failure after 1 cycle of modified Madison-Wisconsin L-CHOP protocol. Postmortem examination revealed bilaterally enlarged lumpy-bumpy shaped kidneys. Histopathologic examination showed an infiltration of malignant lymphocytes into the renal parenchyma and mesentery. Immunohistochemical staining of the renal sample displayed a negative expression of CD3, PAX5, MUM-1, and CD79. The clinical features and prognosis of the cat with renal lymphoma with mesenteric lymphomatosis have been described in this report.

• Journal of Nutrition and Health
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• v.33 no.5
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• pp.507-516
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• 2000

The purpose of this study was to investigate the effect of vitamin C and vitamin E supplementation on the iron contents and oxidative stress of the rats. Rats were fed 18g ascorbic acid and 300IU $\alpha$-tocopherol/kg diet, respectively. Rats were sacrificed at 1, 3, 5 and 7 month of age. The blood, liver and brain were selected for the quantitation of iron and malondialdehyde(MDA) contents, glutathione peroxidase(GSHPx), superoxided dismutase(SOD) and catalase(CAT) activity. Iron and MDA contents and GSHPx activities were increased with aging. Vitamin C and Vitamin E supplementation increased iron contents of the plasma. Vitamin C raised iron contents, but vitamin E decreased iron contents of the liver. In the brain vitamin C and vitamin E did not affect the iron level. MDA levels were decreased with vitamin C and vitamin E supplementation in the erythrocyte and liver, and vitamin C supplementation elevated MDA levels in the brain. GSHPx activity was increased with vitamin C and vitamin E supplementation. SOD activities of erythroucyte and brain were not affected with age, but in the liver, SOD activity was raised with age and vitamin C supplementation. Vitamin C and vitamin E supplementation promoted CAT activity of erythroucyte and liver, and CAT activity of brain was eleveated with vitamin addition but was decreaed with vitamin E addition. Vitamin C and vitamin E decreased iron contents of blood plasma, MDA contents of plasma and liver, and CAT activity of erythrocyte. Above results indicated that iron contents and biomarkers of oxidative stress were more affected by age than antioxidant action of vitamin C and vitamin E.

• Journal of Environmental Science International
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• v.28 no.11
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• pp.983-991
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• 2019

This study investigated the use of a hydroxyl-radicals-generated microbubble/catalyst (MB/Cat) system for removing organic pollutants, nitrogen, and phosphorous from liquid fertilizer produced by livestock wastewater treatment. Use of the MB/Cat system aims to improve the quality of liquid fertilizer by removing pollutants originally found in the wastewater. In addition, a reduction effect has been reported for antibiotics classified as representative non-biodegradable matter. Samples of liquid fertilizer produced by an aerobic biological reactor for swine wastewater treatment were first analyzed for initial concentrations of pollutants and antibiotics. When the MB/Cat system was applied to the liquid fertilizer, TCOD, TOC, $BOD_5$, and $NH_3-N$, and $PO_4-P$ removal efficiencies were found to be approximately 52%, 51%, 30%, 21%, and 66%, respectively. Additionally, Amoxicillin hydrate was removed by 10%, and Chlortetracycline HCl and Florfenicol were not present at detectable levels These findings confirm that the MB/Cat system can be used with livestock wastewater treatment to improve liquid fertilizer quality and to process wastewater that is safe for agricultural re-use.

• Design Convergence Study
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• v.17 no.3
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• pp.1-19
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• 2018

Hand rehabilitation training tools are used in hospitals and at home for patients and users who require recovery of disabled hands and improvement in overall hand function. However, existing training tools are not organized into a progressive system, and they lead to repeatability operations over a period of time. As a result, patients feel free and cannot be motivated by rehabilitation, and continuous rehabilitation training is difficult. Based on this argument, the study combines one of the elements of the game called the "Cat's cradle" to enable the user to feel achievement through play and to achieve natural rehabilitation through unconsciousness. After examining the characteristics of the tool, the user's environment, the relevance of the Cat's cradle game to the training tool and to the patient's continued rehabilitation was established. And design elements were derived through professional interviews. Later, design guidelines and prototypes have been created to complement the problems associated with guidelines and prototypes by conducting usability testing and design element assessment.