• Biomedical Science Letters
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• v.12 no.3
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• pp.289-301
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• 2006

Cardiopulmonary bypass (CPB) for cardiac surgery triggers the production and release of numerous chemotactic substances and cytokines, ensuing systemic inflammatory response that leads to postoperative major organ dysfunction. Traditionally, corticosteroids (steroid) have been administered to patients undergoing cardiac surgery to ward off these detrimental physiologic alterations. However, the majority of the studies have been performed on adult patients with high-dose steroid. We carried out a randomized, prospective, double-blind study to compare the efficacy of low-dose steroid with that of high-dose steroid and to determine the adequate dose of pretreated-steroid for prophylactic effects in pediatric cardiac surgery. Thirty pediatric patients scheduled for elective cardiac surgery were randomly assigned to two groups; fifteen patients received low-dose methylprednisolone (10mg/kg intravenously, n=15, low-dose group) and the others received high-dose methylprednisolone (30mg/kg intravenously, n=15, high-dose group) 1 hour prior to CPB. Arterial blood samples were taken before CPB (Pre-CPB), 10 minutes after start of CPB (CPB-10), and immediately after CPB-end (CPB-OFF) for measuring total leukocyte counts (T-WBC) and diff-counts, platelet counts, interleukin-6 (IL-6), myeloperoxidase (MPO), total antioxidant (TAO), neuron-specific enolase (NSE), troponin I (TNI), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and blood urea nitrogen (BUN) levels. Other parameters such as volumes of urine output, pulmonary index $(PI,\;PaO_2/FiO_2)$, mechanical ventilating period, intensive care unit (ICU)-staying period, postoperative complications (fever, wound problem), postoperative 24 hrs and total volumes in blood loss, and hospitalized days were also assessed. All parameters were compared between two groups. There were no significant differences in T-WBC counts, monocyte fraction, platelet counts, TA levels, NSE levels, creatinine levels, BUN levels, the volumes of total urine output, PI, the incidences of fever and wound problem, postoperative 24hrs- and total-blood loss volumes and ICU-staying period between two groups (P>0.05). At CPB-OFF, neutrophil fraction, MPO level, TNI level, and AST level were higher in the high-dose group than in the low-dose group (P<0.05). IL-6 level at CPB-10 was higher in the high dose-group than in the low-dose group (P<0.05). Furthermore, mechanical ventilating periods and hospitalized days of the high-dose group were significantly longer than those of low-dose group (P<0.05). The high-dose group had significantly low lymphocyte fi-action at CPB-OFF compared with the low-dose group (P<0.001). These findings suggest that pretreatment of high-dose steroid is not superior to that of low-dose steroid regrading its potential benefits in pediatric cardiac surgery. Therefore, the conventional strategy of steroid treatment, high-dose pretreatment, should be modified in the cardiac surgery with CPB. However, further studies must be performed on the larger number of patients in as much as small number of patients in this study.

• Journal of Chest Surgery
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• v.29 no.9
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• pp.989-995
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• 1996

Excessive blood loss secondary to cardiopulmonary bypass(CPB) may be encountered after open heart surgery and platelet dysfunction appears to be especially responsible for this problem. To evaluate the effect of low-dose aprotinin during hypothermic CPB on platelet aggregation, anticoagulation and clinical hemostasis,.40 patients undergoing valve replacement using hypothermic CPB procedures were randomized to give either a low dose aprotinin(2$\times$ 106 KIU in the CPB priming sol- ution, n=20) or a placebo(n=20). During postoperative 24 hours, blood and hemoglobin loss were lower in the aprotinin group (225.5 $\pm$ 121.9ml, and 11.3$\pm$2.4g) than the control group(572.2$\pm$)35.5ml and 26.3$\pm$9.8g)(P<0.01). The total blood and hemoglobin loss were lower in the aprotinin group (622.0$\pm$ 186m1 and 14.7$\pm$6.8g) than the con- trol group (102.1 $\pm$483.5ml and 39.7$\pm$ 16.4g) (P<0.01). The amonut of packed red cell needed decreased in the aprotinin group: 197.7$\pm$56.3ml vers s 651.2: 147.5ml (P<0.01). Hemoglobin concentration, platelet counts and fibrinogen checked at fixed times perioperatively did not differ between the two groups. Platelet aggregation was induced by ADP, collagen, epinephrine and ristocetin before and after CPB. Maximum platelet aggregation was significantly reduced after CPB in control group (ranging from -31 % to -58% relative to prebypass values). Significant prolongation of activated clotting time(ACT) after 5 minute and 30 minute of hypothermic CPB were observed: 955.9 $\pm$35.1 and 967.5$\pm$32.7sec versus 743.8 $\pm$ 52.1 and 731.2: 54.6sec (P<0.01). There was no complication associated with aprotinin infusion. These results demonstrate that low-dose aprotinin significantly reduces blood loss and blood requirment and provides improved postoperative hemostasis which might be related to protection of platelet aggregation capacity.

• Toxicological Research
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• v.2 no.2
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• pp.79-87
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• 1986

Water extracts of 21 traditional Korean herbal drugs were prepared, and a dose range of 100 mg/kg to 400 mg/kg was administered orally into mice once a day for five days. Changes of serum enzyme activities of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), blood urea nitrogen (BUN), alkaline phosphatase, body weight changes and histo pathological examination of various organs were investigated. Water extract of Ephedra Herba caused severe body weight loss at a dose of 100 mg/kg and death from a dose level of 200 mg/kg by oral administration. Angelica koreanae Radix and Anthrisci Radix showed a slight body weight loss and damages to liver and kidney.

• Biomolecules & Therapeutics
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• v.9 no.4
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• pp.307-310
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• 2001

The hair-growth effect of Illite was suggested by some people who were using Illite as a beautifying material. We investigated the hair-growth effect of Illite powder. The hair-growth effects were investigated by two methods; the activity of hair-growth after shaving the hairs on the black mouse (C57BL/6) and the recovery activity of hair-growth after hair-loss induced by cyclophosphamide treatment. Suspension of Illite powder was applied to the back of the black mouse by method of skin paste. Illite promoted significantly the hair growth of mouse in both conditions of shaving and hair-loss. And then we investigated the toxicity which may be induced by Illite when it was administrated orally as a single dose. We could not fond out any significant toxicity induced by single dose oral administration of Illite.

• The Korean Journal of Pharmacology
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• v.7 no.1
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• pp.21-27
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• 1971

The effects of 5 different drugs (amphetamine, caffeine, serotonin, sod. salicylate and pentazocine) on the duration of action of two barbiturates (thiopental and pentobarbital) and an intravenous anesthetic (propanidid) were determined in rats. Duration of action was determined by the time elapsing between loss and return of the righting reflexes. All drugs were injected intraperitoneally except propanidid which was administered by the intravenous route. Preliminary experiments indicated that at a dose of 40 mg/kg either of the two barbiturates or propanidid produced loss of the righting reflexes without death. At this dose, however, the duration of action of propanidid was extremely short. However, this dose was selected for subsequent studies. 1. At the dose employed amphetamine shortened the sleeping time of three compounds. 2. Caffeine and theophylline shortened the sleeping time of thiopental and prolonged the duration of action of pentobarbital. 3. Serotonin had no effect on duration of action of the barbiturates but prolonged the sleeping time produced by propanidid. 4. Sod. salicylate significantly prolonged the sleeping time of the barbiturates whereas pentazocine exhibited this effect only in relation to thiopental.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.214-215
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• 2002

Generally uniform dose distribution is assumed to be formed in a target region when a conventional dose formation method using a broad proton beam, a fixed modulation technique, a bolus and an aperture is employed. However, actual situations differ. We usually find non-uniformity in the target region. This is due to the insertion of a range-compensating bolus before the patient. Since the range-compensating bolus has an irregular shape, the scattering in the bolus depends on the lateral position. Dose distribution is overlapping results of dose distribution of pencil-proton beams traversing different lateral positions of the bolus. The lateral extent of dose distribution of each pencil beam traversing the different position differs each other at the same depth in the target object. This is a cause of the non-uniformity of the dose distribution. Therefore the same lateral extent of dose distribution should be attained for different pencil beams at the same depth to obtain a uniform dose distribution. For that purpose, we propose here a bi-material bolus. The bi-material bolus consists of a low-Z material determining mainly the range loss and a high-Z material defining mainly the scattering in the bolus. After passing through the bi-material bolus, protons traversing different lateral positions will have different residual range yet with the same lateral spread at a certain depth. Using the optimized bi-material bolus, we can obtain a more uniform dose distribution in the target region as expected.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.11-19
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• 1983

Interaction between high energyelectrons and matters had many complex reactions and the high energy electrons lost their energies with collision and scattering, therefore, electrons distribution in matters was shown as various situation by scattering, exciting and ionizing with moleculars. We experimentally studies with 13 MeV Linear Accelerator and thermoluminescence dosimeter using aluminium and Teflon, etc., and measured energy loss of electrons, electron range, electron scattering and dose distribution in matter. We compared the results with theoretical formular, between 4-qw MeV, the energy loss of electrons was decreased by 2 MeV per $1g/cm^2$ but under 1MeV it was rapidly decreased. Electron range in matter reached to $0.5/cm^2$ per 1MeV of incident energy at 6-12MeV. The dose distribution in matter was increased slightly to some depth by total distribution i.e., the combined intensity of primary and secondary radiant and it was rapidly decreased near the maximum range of electrons. Energy loss of electrons and electron range measured by experiment were coincided with theoretical equations of L. Landau and Feather under 5 and 3% errors respectively. The dose distribution of electrons in matter was similar to L.V. Spencer formular, however, we had found that it was quite different in accordance with the field size and that new formular of dose distribution was induced as empirical function contained experimental factors according to field size.

• Nuclear Engineering and Technology
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• v.21 no.2
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• pp.63-72
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• 1989

An analysis for the gamma radiation fields in the research reactor MAPLE-X10 facility has been peformed under the assumption of partial loss of reactor and service pool water to assess the safety from the view point of design. Four photon source terms considered in the analysis were calculated using the ORIGEN-S code. Gamma dose rate calculations over the reactor and service pools during the water-loss accident conditions were performed using QAD-CG code. MCNP code (Monte Carlo Neuron and Photon Transport code), also, was used to assess the scattered radiation fields away from the pools, which is appropriate for calculating the scattered photon dose rates outside of the solid angle subtended by the source and pool walls.

• Journal of Veterinary Clinics
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• v.20 no.4
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• pp.449-457
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• 2003

To investigate the renal effects of enrofloxacin administration on rats induced with dehydration or hyperoxaluria, male rats were treated with enrofloxacin of 50 mg to 500 mg/kg b.w.. The microscopical observations of kidney and urine sediment were carried out in the experimental groups. The result obtained were as follows; The male rats deprived of water for 72 hours and administered with enrofloxacin. As enrofloxacin administration dose was increased, clinical signs such as loss of appetite, depression, weakness, and loss of urine output became more severe. In the histopathological findings, there were hyperemia and hemorrhage in renal cortex, vacuolation and necrosis of renal tubular epithelia, proteinous casts within renal tubules. The male rats were orally administered with sodium oxalate and injected with enrofloxacin for 7days. As enrofloxacin administration dose was increased, clinical signs such as the loss of appetite and water consumption, and weakness became more severe. In the histopathological findings, there are hemorrhage of glomeruli and cortical hyperemia, vacuolation and necrosis of tubular epithelia, proteinous casts in renal tubules. In the microscopical findings of urine sediment, there are calcium oxalate crystal (diamond-like type) and magnesium ammonium phosphate crystals (rhomboid). The male rats were intraperitoneally injected with sodium oxalate and administered with enrofloxacin for 7days. As enrofloxacin administration dose was increased, clinical signs such as the loss of appetite and water consumption, weakness were more severe. In the histopathological findings, there were hyperemia and hemorrhage in both glomeruli and renal cortex. Severe necrosis of renal tubular epithelia, bluish materials within renal tubules were also found. In the microscopical findings of urine sediment, there were many calcium oxalate crystals. The present results suggest that enrofloxacin has some injurious effects in rats having dehydration or hyperoxaluria, and clinically, we should consider these renal injury effects when we use enrofloxacin in patients accompanied renal disease, dehydration and hyperoxaluria conditions.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.564-567
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• 2012

Optical fibers are going to be used for telecommunication, image fibers, sensors under irradiation in nuclear power plants and various irradiation facilities. Especially, Temperature detection sensors using Raman light scattering, temperature or strain sensors using fiber gratings, magnet-optical sensors using photo-magnetic effect, are already commercialized. However, When fibers are exposed to ionizing radiation, color centers are formed in fibers which reduces their light transmission, and it is limited in applying under radiation environments. In this study, $Co^{60}$ gamma-ray induced optical attenuation on Ge-doped single mode(SM) fiber has been measured. Gamma-ray is irradiated for 4hours at the dose rate of 0.5kGy/hr, 2kGy/hr, 8kGy/hr. Consequently, gamma-ray induced loss based on radiation effects in Ge-doped SM fiber occur precisely. Furthermore, dose rate effect that the higher dose rate in the same total dose, the more increase loss of optical fiber and annealing effect that the higher the loss after irradiation, the more increase the recovery rate of the loss are observed in the fiber. This results plan to make use of bases in the study of the radiation-hardened optical fiber.