• Journal of Veterinary Clinics
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• v.29 no.6
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• pp.474-482
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• 2012

Elongation of cheek teeth roots in pet rabbits is very common, and is associated with malocclusion followed by reduced appetite, salivation, periapical abscess, and epiphora. Conservative methods including medication, drainage, irrigation, tooth trimming, intraoral and extraoral extraction, surgical treatment of periapical abscessation, and diet control have been adapted as the only treatments to resolve elongation of teeth roots. However, remaining challenges include the long-term period of cure and recurrence. This study was performed to investigate the possibility of nonvital pulp therapy on elongation of the mandibular cheek teeth roots in pet rabbits. Thirty-one pet rabbits with dental problems due to root elongation were submitted. Ten pet rabbits among them were treated by nonvital pulp therapy procedures (group A), while the others were treated by conservative methods (group B). Appetite improved within 1-5 days after nonvital pulp therapy and the treatment was discontinued 1 month postoperatively in group A. Abscess occurred in another site not treated with nonvital pulp therapy in only two rabbits. Growth of the mandibular cheek teeth treated with nonvital pulp therapy stopped, resulting in malocclusion, intraoral inflammation from the enamel spur, and abscess of the teeth roots. In the group B rabbits treated with conservative therapy, partial drainage, long term medication, recurrent oral trimming and control of repeated oral inflammation occurred. Consequently, buccotomy or tooth extraction was performed in group B. Owners were satisfied with nonvital pulp therapy preventing dental root abscess and repeated troubles including inflammation and malocclusion and reduction of the treatment period. These results suggest that nonvital pulp therapy can be performed on pet rabbits with elongation of mandibular cheek teeth roots.

• Journal of Veterinary Clinics
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• v.26 no.4
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• pp.317-323
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• 2009

This study was performed to evaluate the effect of intravenous administration of glycopyrrolate on cardiovascular and respiratory system in dogs given intravenous medetomidine (20 ${\mu}g$/kg) and intramuscular midazolam (0.3 mg/kg) (MM). Prior to administration of MM, glycopyrrolate was administered intravenously at doses of 5 ${\mu}g$/kg (Gly-5), 10 ${\mu}g$/kg (Gly-10) or 20 ${\mu}g$/kg (Gly-20), respectively. For the control group saline was administered intravenously. In the cardiovascular system, HR, BP, RAP, PAWP, CI, SI, SVR, and PVR were measured. RR, $V_T$, $P_{ETCO2}$, and arterial blood gas analysis were measured for respiratory system. Although rapid and satisfied depth of sedation was obtained by MM, life-threatening bradycardia, the outstanding side-effect on cardiovascular system in dogs were observed. This combination also decreased CO and increased SVR, RAP, and PAWP significantly. The bradycardia could be prevented in all the glycopyrrolate treated groups, but tachycardia was observed in Gly-10 and Gly-20 groups. Significant increases in blood pressure were shown in glycopyrrolate treated groups. Also, tachycardia depends on dose of glycopyrrolate, compensating the CO. However, these were not fully reserved. In conclusion, MM combination could induce rapid and satisfied depth of sedation but was not the suitable method for the deep sedation of dogs with cardiovascular or circulatory problems.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.560-566
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• 1998

Background: Bovine pericardial bioprosthesis treated with glutaraldehyde (GA) is one of the most popular prosthetic materials, but late calcific degeneration after implantation is a problem that remains unsolved. For the purpose of mitigating the calcific degeneration, we added MgCl2 into the 0.625% GA solution to compete with calcium for binding to the free aldehyde from GA and pretreated with the surfactants like sodium dodecyl sulfate (SDS) and Triton X-100 before GA fixation for preventing the phospholipid infiltration into the pericardial tissue, the first step of the calcific degeneration. Material and Method: 40 square-shaped pieces of bovine pericardia were fixed in 0.625% GA solution with 4g/L MgCl2 6H2O as a control group (group 1). 40 pieces pretreated with 1% SDS were also fixed in the same GA solution (group 2) and other 40 pieces pretreated with 1% Triton X-100 were prepared with the same method (group 3). After 1 month of fixation these were implanted into the belly of 40 Sprague-Dawley subdermally and extracted 1 month, 2 months, 3 months and 6 months after implantation. With atomic absorption spectrophotometry we measured the deposited calcium amount. Result: 1 month after implantation we could not find any differences between the three groups, but by the 2nd month calcium deposition was 0.921$\pm$0.121 mg/g in group 1, 0.481$\pm$0.037 mg/g in group 2 and 1.369$\pm$0.200 mg/g in group 3. By the 3rd month it was 0.786$\pm$0.080 mg/g in group 1, 0.584$\pm$0.054 mg/g in group 2 and 1.139$\pm$0.188 mg/g in group 3, and on the 6th month 1.623$\pm$0.601 mg/g in group 1,0.501$\pm$0.043 mg/g in group 2 and 1.625$\pm$0.382 mg/g in group 3, with statistical significance in group 2(p<0.05). Conclusion: Pretreatment with SDS showed meaningful calcium mitigation effects on subcutaneously implanted bovine pericardium in the rat models but the neutral type surfactant, Triton X-100, had no positive mitigation effect in this experiment.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.637-647
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• 1999

Background: Ischemia-reperfusion injury is one of the major contributing causes of early graft failure in lung transplantation. It has been suggested that triiodothyronine (T3) may ameliorate ischemia-reperfusion injury to various organs in vivo and in vitro. Predicting its beneficial effect for ischemic lung injury, we set out to demonstrate it by administering T3 into the in situ canine ischemia-reperfusion model. Material and Method: Sixteen adult mongrel dogs were randomly allocated into group A and B. T3 $(3.6\mug/kg)$ was administered before the initiation of single lung ischemia in group B, whereas the same amount of saline was administered in group A. Ischemia was induced in the left lung by clamping the left hilum for 100 minutes. After reperfusion, various hemodynamic parameters and blood gases were analyzed for 4 hours while intermittently clamping the right hilum in order to allow observation of the injured left lung function. Result: Arterial oxygen partial pressure $(PaO_2)$ decreased 30 minutes after reperfusion and recovered gradually thereafter in both groups. In group B the decrease of $PaO_2$ was less marked than in group A. The recovery of $PaO_2$ was faster in group B than in group A. The differences between the two groups were statistically significant from 30 minutes after reperfusion $(125\pm34$ mmHg and $252\pm44$ mmHg, p<0.05) until the end of the experiment $(178\pm42$mmHg and $330\pm37$ mmHg, p<0.05). The differences in the arterial carbon dioxide pressure, airway pressure and lung compliance showed no statistical significance. The malondialdehyde (MDA) level, measured from the tissue obtained 240 minutes after reperfusion, was lower in group B $(0.40\pm0.04\mu$M) than in group A $(0.53\pm0.05\mu$M, p<0.05). The ATP level of group B $(0.69\pm0.07\mu$M/g) was significantly higher than that of group A $(0.48\pm0.07\mu$M/g, p<0.05). The microscopic exami nation revealed varying degrees of injury such as perivascular neutrophil infiltration, capillary hemorrhage and interstitial congestion. There were no differences in the microscopic findings between the two groups. CONCLUSION T3 has beneficial effects on the ischemic canine lung injury including preservation of oxygenation capacity, less production of lipid peroxidation products and a higher level of tissue ATP. These results suggest that T3 is effective in pulmonary allograft preservation.

• Journal of Chest Surgery
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• v.36 no.3
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• pp.131-135
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• 2003

Bovine pericardium fixed in glutaraldehyde solution (GA) has been one of the most popular surgical bioprosthesis, however, late calcific degeneration after implantation remains to be solved. To mitigate calcific degeneration, we posttreated the bovine pericardium with amino acids after GA fixation. Material and Method: 40 small pieces of bovine pericardia were fixed in 0.625% GA solution with 4 g/L $MgCl_26H_2O$as a control group (group 1). 40 pieces fixed in the same GA solution were posttreated with 2% chitosan solution (group 2) and the other 40 pieces posttreated with 8% glutamate (group 3). These were implanted into the belly of forty Fisher 344 rats subdermally and extracted at f month, 2 months, 3 months and 4 months after implantation. Result: With atomic absorption spectrophotometry we measured the deposited calcium amount and the results were as follows; 2.01 $\pm$0.13 mg/g in group 1, 2.34$\pm$0.73 mg/g in group 2, 2.49$\pm$0.15 mg/g in group 3 at 1 month after implantation, and 3.57$\pm$0.15 mg/g in group 1, 3.52$\pm$0.92 mg/g in group 2, 3.46$\pm$0.12 mg/g in group 3 at the second month. But 5.45$\pm$0.42 mg/g in group 1, 3.22 $\pm$1.31 mg/g in group 2 and 4.20$\pm$0.55 mg/g in group 3 at the 3rd month, which have statistical significance in group 2 (p<0.05). Finally at 4th month, 6.01$\pm$1.21 mg/g in group 1, 3.78$\pm$1.82 mg/g in group 2, 3.92$\pm$0.92 mg/g in group 3, which also have statistical significance (p < 0.05). Conclusion: This means posttreatment with 2% chitosan shows meaningful calcium mitigation effects after 3rd month on subcutaneously implanted bovine pericardium in the rat models but 8% glutamate shows mitigation effect after 4months in this experiment.

• Journal of Chest Surgery
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• v.36 no.10
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• pp.721-727
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• 2003

Background: Parenteral tetracycline is no longer available for pleural sclerosing agent for pleurodesis in Korea due to the discontinuation of the production. The purposes of this study were to determine whether oral doxycycline (ODC) could be used as an effective sclerosing agent for pleurodesis, and to compare the effectiveness of ODC to other agents, such as homologous blood and talc. Material and Method: Twenty male rats were divided into four groups (A to D). Following agents were given to each group intrapleurally; 10 $m\ell$/kg of 0.9% saline to group A, 10 mg/kg of ODC to group B, 2 $m\ell$/kg of homologous blood to group e, and 70 mg/kg of talc slurry to group D. All animals were sacrificed 28 days after instillation. The pleural spaces were assessed grossly and microscopically and were graded from 0 to 3, and the thicknesses of the pleura were measured. Result: The gross score of group A was 0.0, group B was 1.4$\pm$0.9, group e was 1.0$\pm$0.7, and group D was 2.2$\pm$0.8. Significant adhesion were examined in group B and D grossly (p < 0.05). The pleural thickness of group A was 0.7$\pm$0.2 /10$^2$ mm, group B was 1.2$\pm$0.4 /10$^2$ mm, group C was 1.4$\pm$0.4 /10$^2$ mm, and group D was 3.5$\pm$0.9 /10$^2$ mm. Group D showed pleural thickening significantly (p < 0.05). The microscopic score of group A was 1.0, group B was 1.7$\pm$0.5, group e was $1.5\pm$0.4, and group D was 2.8$\pm$0.4. Group B and D showed significant inflammations and depositions of collagen (p < 0.05). Conclusion: ODC showed significant pleurodesis grossly and microscopically, and homologous blood did not show adhesion. Talc was a significant sclerosing agent for pleurodesis causing extensive inflammation and collagen depisotion.

• Journal of Chest Surgery
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• v.38 no.10 s.255
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• pp.661-668
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• 2005

Background: We have hypothesized that, if a low resistant gravity-flow membrane oxygenator is used, then the twin blood sacs of TPLS can be located at downstream of the membrane oxyenator, which may double the pulse rate at a given pump rate and increase the pump output. The purpose of this study was to determine the optimal configuration for the ECLS circuits by using the concept of pulse energy and pump output. Material and Method: Animals were randomly assigned to 2 groups in a total cardiopulmonary bypass model. In the serial group, a conventional membrane oxygenator was located between the twin blood sacs. In the parallel group, the twin blood sacs were placed downstream of the gravity-flow membrane oxygenator. Energy equivalent pressure (EEP) and pump output were collected at pump-setting rates of 30, 40, and 50 BPM. Result: At the given pump-setting rate, the pulse rate was doubled in the parallel group. Percent changes of mean arterial pressure to EEP were $13.0\pm1.7,\; 12.0\pm1.9\;and\;7.6\pm0.9\%$ in the parallel group, and $22.5\pm2.4,\; 23.2\pm1.9,\;and\;21.8\pm1.4\%$ in the serial group at 30, 40, and 50 BPM of pump-setting rates. Pump output was higher in the parallel circuit at 40 and 50 BPM of pump-setting rates $(3.1\pm0.2,\;3.7\pm0.2L/min\;vs.\;2.2\pm0.1\;and\;2.5\pm0.1L/min,\;respectively,\;p=0.01)$. Conclusion: Either parallel or serial circuit configuration of the ECLS generates effective pulsatility. As for the pump out, the parallel circuit configuration provides higher flow than the serial circuit configuration.

• Journal of Chest Surgery
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• v.32 no.5
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• pp.413-421
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• 1999

Background: Ischemia reperfusion injury is known to contribute to the major causes of the early graft failure in lung transplantation. Triiodothyronine (T3) has been suggested to ameliorate ischemia reperfusion injury from both in vivo and in vitro experiments of various organs. Prospecting its beneficial effect for pulmonary allograft preservation, we made a new solution by adding T3 into the extracellular type dextran solution. Material and Method: Twelve adult mongrel dogs underwent left lung allotransplantation. Six donor dogs were flushed with the new solution(Group 1, n=6), and the remaining six were flushed with Euro-Collins solution to serve as controls(Group 2, n=6). Allografts were stored in each preservation solution for 20 hours at 4$^{\circ}C$. Left single lung transplantations were performed. The right pulmonary artery and the right main bronchus were clamped at 15 minutes after the reperfusion and maintained throughout the experiment to evaluate the transplanted left lung function. Result: Arterial carbon dioxide tension was better in group 1 than in group 2 throughout the experiment period and the difference was statistically significant at 2 hours after reperfusion(28.0${\pm}$3.0 mmHg and 53.1${\pm}$17.4 mmHg, p<0.05). The differences of arterial oxygen partial pressure, peak airway pressure and pulmonary vascular resistance showed no statistical significance. The malondialdehyde(MDA) level, measured from tissue obtained at 120 minutes after reperfusion showed no statistically significant difference. The tissue wet/dry ratio of group 1(649${\pm}$27 %) was significantly lower than that of group 2(686${\pm}$71 %, p<0.05). The microscopic examination revealed varying degrees of injury represented mainly by findings such as perivascular neutrophil infiltration, capillary hemorrhage and interstitial congestion. These findings were less severe in group 1 than those in group 2. Conclusion: The new solution demonstrated superior allograft preservation after 20 hour ischemia compared to Euro-Collins solution in canine single left lung transplantation model, these results suggest that T3 might be a promising agent for pulmonary allograft preservation.

• Journal of Chest Surgery
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• v.36 no.12
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• pp.894-903
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• 2003

Protection against ischemia-reperfusion injury is crucial for successful transplantation of the lung. It has been known that nitric oxide has many favorable effects on the donor lungs but at the same time, has some potential side effects of cytotoxicity. In this regards, we investigated whether the administration of nitroglycerin could decrease ischemia-reperfusion injury in isolated rat lung reperfusion model for the confirmation of the effect of nitroglycerin, a donor of nitric oxide, on lung transplantation. Material and Method: 35 Sprague-Dawley species male white rats were used for this experiment. For nitroglycerin group (n=18), nitroglycerin was administered intravenously followed by mixed in flushing solution for preservation. As a control group (n=17), we used the same amount of normal saline. To evaluate the effect of nitroglycerin on the lung, heart-lung block was obtained, weighed and stored in University of Wisconsin Solution at 1$0^{\circ}C$ for 24 hours. In each group of the isolated lungs, reperfusion was carried out with Krebs-Hensleit-diluted human blood for 60 minutes. As parameters of the state of the isolated lung, peak inspiratory and pulmonary arterial pressures were continuously recorded. Oxygen and carbon dioxide tension of reperfusing blood were measured before and after 30, 60 minutes of reperfusion. After sixty minutes of reperfusion, protein content in bronchoalveolar lavage fluid was measured also for the evaluation of the degree of alveolar flooding. Lung myeloperoxidase activity was determined to verify the accumulation of neutrophils. Results: Although statistically significant differences were not noted in peak inspiratory and pulmonary arterial pressure between control and nitroglycerin group, latter group showed lowering tendency of pulmonary arterial pressure during the entire reperfusion period. Oxygen tension was higher (p<0.05) in nitroglycerin group compared with that of the control group, in contrast, there were no differences in carbon dioxide tension, protein content in bronchoalveolar lavage fluid and myeloperoxidase activity between the groups. In the examination of ultrastructural changes, nitroglycerin denoted the protective effect on the pulmonary architecture compared with that of control group. Conclusion: Collectively, on the bases of these experimental results, prior treatment of donor lung with nitroglycerin could result in better preservation of the lung. Consequently, these nitroglycerin preserved lungs are thought to be more suitable for successful transplantation of the lung.

• The Korean Journal of Nuclear Medicine
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• v.32 no.6
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• pp.525-533
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• 1998

Purpose: Radiation adaptive response in human peripheral lymphocytes and mouse bone marrow cells was investigated using both metaphase analysis and micronucleus assay. We assessed the correlation between both tests. Materials and Methods: Two groups of the human peripheral lymphocytes and mouse bone marrow cells were exposed to low dose (conditioning dose, 0,18 Gy) or high dose (challenging dose, 2 Gy) ${\gamma}$-rays. The other 4 groups were exposed to low dose followed by high dose after several time intervals (4, 7, 12, and 24 hours, respectively). The frequencies of chromosomal aberrations in metaphase analysis and micronuclei in micronucleus assay were counted. Results: Chromosomal aberrations and micronuclei of preexposed group were lower than those of the group only exposed to high dose radiation. Maximal reduction in frequencies of chromosomal aberrations were observed in the group to which challenging dose was given at 7 hour after a conditioning dose (p<0.001). Metaphase analysis and micronucleus assay revealed very good correlation in both human lymphocytes and mouse bone marrow cells (r=0.98, p<0.001 ; r=0.99, p=0.001, respectively). Conclusion: Radiation adaptive response could be induced by low dose irradiation in both human lymphocytes and mouse bone marrow cells. There was a significant correlation between metaphase analysis and micronucleus assay.