• Development and Reproduction
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• v.25 no.2
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• pp.83-91
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• 2021

The present study was performed to investigate the effect of maternal hypothyroidism and puberty onset in female rat pups. To do this, we employed propylthiouracil (PTU) to prepare a hypothyroid rat model. Pregnant rats were treated with PTU (0.025%) in drinking water from gestational day 14 to postnatal day 21 of offspring. Comparison of general indices such as body and tissue weights and puberty indices such as vaginal opening (VO) and tissue histology between control and PTU-treated rats were conducted. There was no significant difference in the date of VO between control and PTU group. The body weights of the PTU group were significantly lower, only 36.8% of the control group (p<0.001). Although the absolute thyroid weight was not changed by PTU treatment, the relative weight increased significantly about 2.8 times (p<0.001), indicating that hypothyroidism was successfully induced. On the other hand, the absolute weights of the ovary and uterus were markedly decreased by PTU administration (p<0.001), and the relative weight was not significantly changed. The ovarian histology of PTU group revealed the advanced state of differentiation (i.e., presence of corpora lutea). Inversely, the uterine histology of PTU group showed underdeveloped structures compared those in control group. Taken together, the present study demonstrates that our maternal hypothyroidism model resulted in minimal effect on pubertal development symbolized by VO despite of huge retardation in somatic growth. More sophisticatedly designed hypothyroidism model will be helpful to achieve a better understanding of pubertal development and related disorders.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.2
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• pp.101-123
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• 2011

Objectives : The aim was to study the effect of bee venom pharmacopuncture therapy with different concentration on rheumatoid arthritis rat model. Methods : We enforced a bee venom pharmacopuncture therapy with different concentration on rheumatoid arthritis rat model by the intradermal injection of chicken type II collagen emulsified. 14 days after the onset of the rheumatoid arthritis rat model, a fixed volume of bee venom was daily injected to ST-35 acupoint in the rat's knee joint for 2-3 weeks. The hind paw volume, arthritic index, arthritic flexion pain test, pain threshold, and serum analysis (CRP, $PGE_2$, ALT, AST) were analyzed, and the expression profiles of COX-2, c-fos, and substance-P at the dorsal horn region of the spinal cord and subchondral bone of the knee joint were also analyzed by using the immunohistochemistry. Results : After the treatment of rheumatoid arthritis rats with bee venom pharmacopuncture, the paw volume of edema of arthritic rats were almost restored to the level of normal group, and behavior tests were very effective. Also the evaluation on the blood serum analysis was remarkable. COX-2, c-fos, and substance-P positive cells in the immunohistological section of dorsal horn region of the spinal cord and subchondral bone of the knee joints were significantly decreased. also the bee venom pharmacopuncture was effective to alleviate their rheumatoid arthritic inflammation cytokine inhibition as regards to the behavior tests and joint histological appearance. Conclusions : Based on the results in this study, bee venom pharmacopuncture with concentrated treatment condition was very effective in low fixed quantity and progressive low increased quantity.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.739-745
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• 2001

Of all pesticides, carbamates are known to be most common, since alternatives such as organophosphates have long lifetime and are extremely toxic to produce a delayed neurotoxic effect. Although a number of studies about toxicity of carbofuran, a most widely used carbamate, have been reported, its cardiovascular toxicity has not yet been studied. In the present study, we investigated its cardiovascular toxic effect in anesthetized rat in vivo and in isolated Langendorff rat heart, In anesthetized rat model, carbofuran (10 mg/kg) significantly reduced heart rate, and transiently increased blood pressure. In isolated rat heart, carbofuran (10${\mu}{\textrm}{m}$) caused a significant depression in the left ventricular developed pressure (LVDP), indicating contractile dysfunction by carbofuran. Carbofuran (10${\mu}{\textrm}{m}$) also decreased coronary flow rate (CFR) in isolated heart, indicating carbofuran-induced coronary dysfunction. These results suggest that carbofuran can cause cardiac dysfunction in rat in vivo and vitro.

• Journal of Chest Surgery
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• v.27 no.7
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• pp.563-570
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• 1994

Effect of ischemic preconditioning on left ventricular function after cardiac arrest in isolated rat heart.Ischemic preconditioning reduces infarct size caused by sustained ischemia. However, the effects of preconditioning on post ischemic cardiac function are not well-known. The objective of the present study was to determine whether preconditioning would improve the recovery of left ventricular functions after cardiac arrest in isolated rat heart model.Isolated rat hearts were allowed to equilibrate for 20 minutes and were then subjected to either 5 minutes of global, normothermic transient ischemia [Group 2 and 4] or not [Group 3]. A stabilization period of perfusion lasting 5 minutes after the termination of transient ischemia was followed by a standard global, normothermic 20 minute-ischemia and 35-minute reperfusion challenge [Group 3 and 4]. These following results were odtained.1. The recovery of left ventricular developed pressures showed no significant differences between Group 3 and Group 4 at 50 [P>0.3] and 85 minute [P>0.2].2. Heart rates showed no significant differences throughout all the course of experiment and between groups [P>0.5].3. The recovery of left ventricular maximum dP/dt showed no significant differences between Group 3 and Group 4 at 50 [P>0.1] and 85 minute [P>0.2].4. The recovery of pressure-rate products showed no significant differences between Group3 and Group 4 at 50 [P>0.5] and 85 minute [P>0.1].These results suggest that ischemic preconditioning does not provide significant benefit for the postischemic left ventricular functions in isolated rat hearts.

• Journal of Chest Surgery
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• v.24 no.5
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• pp.429-437
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• 1991

Beta hydroxytrimethylammonium butyrate[L-carnitine] is highly concentrated in myocardium and it is essential substance for transfer of fatty acids into the mitochondria. We respect that L-carnitine has protective action to myocardium during ischemia. I studied coronary flow and CK - MB isoenzyme of coronary effluent of Langendorff`s isolated rat heart model. As a control group 5 Sprague-Dowley species rat hearts were connected to Langendorff`s isolated rat heart model and perfused for 30 minutes with Kreb-Henseleit buffer solution. After cessation of perfusion for 30 minutes they were reperfused for 30 minutes. In experimental group 10 Sprague-Dowley species rat hearts were perfused with 10mmole /L of L-carnitine contained in Kleb-Henseleit buffer solution. In equilibrium state, coronary flow was 1.7 times greater in experimental group. During reperfusion, both group showed equally decreased flow amount of about 60% of that of equilibrium state. CK-MB isoenzyme level of perfused coronary fluid showed no significant difference in equilibrium state. In reperfusion. CK-MB isoenzyme levels of control group were 17.61$\pm$8. 68U/L at 25 minutes, 23.32$\pm$4.15U /L at 30 minutes; and in experimental group, 13.63$\pm$6. 08U/L at 15 minutes and 13.6$\pm$8.41U /L at 30 minutes respectively. Those values in both states showed significantly lower CK-MB level in experimental group. In conclusion, L-carnitine prevent ischemic myocardial damage during ischemic and reperfusion state of Langendorff`s isolated rat hearts and also I suggest the L-carnitine act potent coronary vasodilator during preischemic and postischemic states of rat hearts.

• Journal of Korea Water Resources Association
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• v.47 no.10
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• pp.959-972
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• 2014

In this study, a space-time rainfall grid field generation model based on multifractal theory was verified using nine flood events in the upstream watershed of Chungju dam in South Korea. For this purpose, KMA radar rainfall data sets were analyzed for the space-time multifractal characteristics. Simulated rainfall fields that represent the multifractal characteristics of observed rainfall field were reproduced using the space-time rainfall grid field generation model with log-Poisson distribution and three-dimension wavelet function. Simulated rainfall fields were applied to the S-RAT model as input data and compared with both observed rainfall fields and low-resolution rainfall field runoff. Error analyses using RMSE, RRMSE, MAE, SS, NPE and PTE indicated that the peak discharge increases about 20.03% and the time to peak decreases about 0.81%.

• Archives of Plastic Surgery
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• v.39 no.5
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• pp.452-456
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• 2012

Background Phosphatidylcholine (PPC) and deoxycholate (DCA) compound has been recently used for the purpose of partial lipolysis and is valued for its efficacy and lower invasiveness compared to liposuction and dermolipectomy used previously. In this article, the authors discuss the efficacy of the PPC dissolved in DCA via an experimental rat study model, along with suggesting a useful animal experimental model for the study of adipose tissue and lipolysis. Methods Bilateral inguinal fat pads of an experimental rat were elevated with the deep inferior epigastric vessel as the sole vascular pedicle. Normal saline was injected on one side as a control group and a PPC and DCA compound was injected on the other side. After 4 days, the rats were euthanized for microscopic tissue examination. The pathology was scored by a sem-iquantitative system in 4 categories: normal fat amount, fat necrosis, inflammatory activity, and stage of fibrosis. A Wilcoxon signed-rank test powered by SPSS packet program was used for statistical analysis and to determine significance. Results Microscopic examination was performed on the obtained samples, and the experimental data of all four categories showed significant histologic differences compared to the control group. All of the data also showed statistical significance by the Wilcoxon signed-rank test (P<0.01). Conclusions In the inguinal fat pad rat model, the control group and the experimental group had a differed significantly in the amount of normal fat tissue, inflammation, necrosis, and fibrosis. We recommend the rat inguinal fat pad model used in this study, as it is likely to be useful in related research.

• Journal of Acupuncture Research
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• v.20 no.3
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• pp.117-130
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• 2003

To study the analgesic and effect and its mechanism of eletroacupunture(EA) on the chronic inflammatory pain 50 rats were induced with arthralgesia by injecting complete freund's adjuvant(CFA). Two weeks after the injection of CFA, EA stimulation(2Hz, 0.07mA, 0.3ms) was delivered to Jogsamni($ST_{36}$) for 20 minutes. Analgesic effect was evaluated by using the tail flick latency(TFL) and the analgesic mechanism was observed by applying TFL with the pretreatment with naloxone and yohimbine. The results were as follows ; 1. TFL level for the model of adjuvant-induced arthritis decreased as time went by and it induced the hyperalgesia. 2. EA stimulation delivered to Jogsamni($ST_{36}$) for 20 minutes in the rat model of adjuvant-induced arthritis brought analgesic effect and its effect had lasted for 40 minutes after the stimulation. 3. The analgesic effect of Jogsamni($ST_{36}$) EA in the rat model of adjuvant-induced arthritis was blocked by pretreatment with naloxone(2mg/kg,i.p). This result suggests that the EA effect on the chronic inflammatory pain can be related to the endogenous opioid mechanism. 4. The analgesic effect of Jogsamni($ST_{36}$) EA in the rat model of adjuvant-induced arthritis was blocked by pretreatment with naloxone(2mg/kg,i.p). This result suggests that the EA effect on the chronic inflammatory pain can be related to the ${\alpha}_2$-adrenergic mechanism.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.147-147
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• 2002

This experimental study was carried out to investigate on the safety of Nog-yong aqua-acupuncture solution in primary culture of adult rat hepatocytes. Primary culture of adult rat hepatocytes has been considered as a ideal model for toxicological studies because cultured hepatocytes maintained many liver-specific functions. In this research, we investigated the effects of Nog-yong aqua-aqupunture(1-10$\mu\textrm{g}$/ml) on cytotoxicites in primary culture of adult rat hepatocytes using LDH release assays. Hepatic glutathione level. glutathione-S-transferase activity, and albumin synthesis were not affected by treatment with Nog-yong aqua-aqupuntur alone. Nog-yong aqua-aqupuncoure solution(0.5-$10{\mu}\textrm{g}$/ml) on cytotoxicites in primary culture of adult rat hepatocytes using LDH release not significantly affected normal functional charaterists.

• Progress in Superconductivity
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• v.12 no.2
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• pp.124-128
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• 2011

We have developed a high-$T_C$ SQUID magnetometer system to measure magnetocardiograms of laboratory rats. White noise of the measurement system was about 50 fT/$Hz^{1/2}$ when measured in a magnetically shielded box. We optimized the measurement position to obtain clear MCG wave from rat's small heart by using grid measurements. With the optimization, the MCG signal was successfully detected with the peak amplitude of about 50 pT. We could observe well defined P-, QRS-, and T-wave from the rat MCG. The results suggest that the developed system has a strong potential to monitor the progress of heart disease model using laboratory rat.