BACKGROUND: The action of the volatile anesthetics on various organs in the body is not well known. Since Furchgott (1980) discovered endothelium derived relaxing factor (EDRF) from endothelium, many studies have been tried. Many investigators were studied about the relationship between the EDRF and the effect of the volatile anesthetics on blood vessels too. But the effect of volatile anesthetics and the site of action on the blood vessel were still controversial. In this study, we evaluated that the effect and the action site of halothane and isoflurane on isolated aortic rings of the rabbit. METHODS: Each of obtained thoracic aorta from rabbits (1.5~2.5 Kg) was divided into 3~5 mm sized rings, and a half of that were denuded. All of the aortic rings were preconstricted with phenylephrine 1.5 10-7 Mole in warm organ bath filled with modified Krebs' solution, and then LNAME (inhibitor of nitric oxide synthase, 3 10-4Mole) was administered to one group of aortic rings. MB (inhibitor of soluble guanylate cyclase, 2 10-5Mole) was administered to another one group and neither of LNAME nor MB was administered to the other group. And then isoflurane or halothane was administered (1~4%) to all of aortic rings. The polygraph recorded the changes of tension of aortic ring which was transmitted through the force transducer. RESULTS: It was proved that basal EDRF was released from endothelium by the fact that intact aortic rings were more constricted after LNAME or MB administration. The intact aortic rings were constricted in all concentration of isoflurane and both intact and denuded rings were relaxed in 4% concentration of halothane. CONCLUSION: It is concluded that isoflurane in all concentrations has an endothelium -mediated vasoconstriction and 4% halothane produced vascular relaxation directly independent of existence of the endothelium of vessel.
Anesthetics ; Aorta, Thoracic ; Arginine* ; Baths ; Blood Vessels ; Endothelium ; Endothelium-Dependent Relaxing Factors ; Guanylate Cyclase ; Halothane* ; Humans ; Isoflurane* ; Methylene Blue ; Nitric Oxide Synthase ; Phenylephrine ; Rabbits ; Relaxation ; Research Personnel ; Transducers ; Vasoconstriction

BACKGROUND: Desflurane is a new inhaled anesthetic with the lowest blood/gas partition coefficient and enflurane is one of the major anesthetics in these days. But the effect of volatile anesthetics and the site of action on the blood vessel are still controversial. Since Furchgott (1980) discovered endothelium derived relaxing factor (EDRF) from endothelium, many investigators have studied about the relationship between the EDRF and the effect of the volatile anesthetics on blood vessels. In this study, we evaluated that the effect and the action site of enflurane and desflurane on isolated aortic rings of the rabbit. METHODS: Each of obtained thoracic aorta from rabbits (1.5~2.5 kg) was divided into 4~6 mm rings, and a half of that were denuded. All of the aortic rings were preconstricted with phenylephrine 1.5 10-7 Mole in warm organ bath filled with modified Krebs' solution, and then LNAME (inhibitor of nitric oxide synthase, 3 10-4Mole) was administered to one group of aortic rings. MB (inhibitor of soluble guanylyl cyclase, 2 10-5Mole) was administered to another one group and neither of LNAME nor MB was administered to the other group. And then enflurane (1%, 2%, 3%, 4%) or desflurane (6%, 9%, 12%) was administered to all of aortic rings. The polygraph recorded the changes of tension of aortic ring which was transmitted through the force transducer. RESULTS: It was proved that basal EDRF was released from endothelium by the fact that intact aortic rings were more constricted after LNAME or MB administration. The intact aortic rings were constricted in all concentration of enflurane and both intact and denuded rings were maintained from control tension in all concentrations of desflurane. CONCLUSION: It is concluded that enflurane in all concentrations has an endothelium-mediated vasoconstriction effect and desflurane in all concentrations has no effect on isolated aortic rings of rabbit.
Anesthetics ; Aorta, Thoracic ; Arginine* ; Baths ; Blood Vessels ; Endothelium ; Endothelium-Dependent Relaxing Factors ; Enflurane* ; Guanylate Cyclase ; Humans ; Nitric Oxide Synthase ; Phenylephrine ; Rabbits ; Research Personnel ; Transducers ; Vasoconstriction

No abstract available.
Animals ; Hindlimb Suspension* ; Hindlimb*

BACKGROUND: Chronic cutaneous lupus erythematosus(CCLE) is a well-known disease entity. But there has been no data about its clinical behavior and histopathologic features in Korea. OBJECTIVES: This study was conducted to elucidate the clinical, laboratory, and histopathologic features of CCLE, and the relationship between CCLE and SLE. MATERIALS AND METHODS: We investigated 48 cases of CCLE that visited the department of dermatology at the Seoul National University Hospital from January 1990 to June 1997. Medical records and biopsy slides were reviewed.
Biopsy ; Dermatology ; Korea ; Lupus Erythematosus, Cutaneous* ; Medical Records ; Seoul

No abstract available.
Anencephaly* ; Autopsy*

We developed an animal model to recreate the condition of an open fracture in communication with the maxillary sinus. We then studied wound healing of the sinus wall structures following fracture in the presence of autogenous bone and alloplastic implant. This model is designed to simulate the repair of an orbital floor fracture in humans. The New Zealand White rabbit was used as the animal model. Standardized 8mm defects were made bilaterally in the maxillary sinuses to include bone and mucosa in 36 rabbits. Two different implants and autogenous calvarial bone graft were placed in the soft-tissue pockets to obturate the defects, exposing one surface of the implant to the open sinus. Medpor porous polyethylene, silicone and calvarial bone implant were compared. Animals were killed at 1, 2 and 8 weeks after implantation. Gross examination of the specimens for the amount of mucosal closure and implant tissue fixation was performed. Histological sections were evaluated for bone and soft-tissue morphology juxtaposed to the implant. Complete closure of the mucosal defect was demonstrated with each type of implant. Medpor implants showed both vascular and soft-tissue ingrowth into pores by week 1. Bone ingrowth was seen by week 2. Closure of the Medpor obturated defects occurred more rapidly than in the silicone group. The Medpor implants and calvarial bone demonstrated bone and soft-tissue fixation, callus formation and maturation, while mature overlying mucosa was reconstituted over the defects. Silicone implants demonstrated a fibrous tissue reaction within 1 week of implantation and they never became fixed to bone or soft tissue. Maxillary sinus wall regeneration occurred in all defects. This study supports clinical observations of maxillary sinus wall regeneration in humans.
Animals ; Bony Callus ; Fractures, Open ; Humans ; Maxillary Sinus ; Models, Animal ; Mucous Membrane ; New Zealand ; Orbit ; Polyethylene ; Rabbits ; Regeneration ; Silicones ; Tissue Fixation ; Transplants ; Wound Healing

BACKGROUND: Exercise testing is an importnat diagnostic and prognostic procedure in the assessment of patients with ischemic heart disease. But standard ST-segment depression criteria was not high enough to estimate coronary srtery disease. Recently, the heart rate adjustment of ST segment depression, ST segment/heart rate slope and index, have been proposed as a more accurate criteria for diagnosing significant coronary artery disease. The objective of this study was to compare the discriminating power of proposed ST segment/heart rate slope and index with that of a standard method of assessing exercise-induced ST segment depression for estimating coronary artery disease. METHODS: Sixty nine patients with ischemic heart disease were studied with exercise treadmill testing and coronary angiography. Computer-measured ST-segment amplitudes were obtained and analysis of the heart rate-adjusted ST segment depression(ST/HR slope and big up tri, Delta ST/HR index) was done. The sensitivity, specificity, and extent of coronary artery disease on each criteria were compared. RESULTS: 1) The sensitivity of big up tri, Delta ST/HR index partition of 1.6uV/beats/min was slightly higher(83%) and the specificity of ST/HR slope partition of 2.4uV/beats/min was higher(87%) than the standard exercise electrocardiographic criteria. 2) Early onset of ischemic ST-segment depression, profound ST-segment depression(> or =2mm), and downsloping ST-segment were associated with more extensive coronary artery disease. 3) On ST/HR slope, no CAD was 1.7+/-0.26uV/beats/min, one vessel disease was 2.6+/-0.34 uV/beats/min, two vessel disease was 2.7+/-1.36uV/beats/min, one vessel disease was 2.8+/-0.35uV/beats/min, and on big up tri, Delta ST/HR index, no CAD was 1.8+/-0.38uV/beats/min, one vessel disease was 2.8+/-1.36uV/beats/min, two vessel disease 3.4+/-1.44uV/beats/min, and three vessel disease was 3.7+/-2.95uV/beats/min. The increment of ST/HR slope and big up tri, Delta ST/HR index were associated with the coronary artery disease and its severity, but the correlations were not high enough. CONCLUSION: The heart rate adjustment of ST segment depression was not high enough for improved detection of coronary artery disease, compared with standard ST-segment depression criteria. But these indexes can be improved the clinical usefulness of the treadmill exercise test for coronary aretry disease.
Coronary Angiography ; Coronary Artery Disease* ; Coronary Vessels* ; Depression* ; Electrocardiography ; Exercise Test ; Heart Rate* ; Heart* ; Humans ; Myocardial Ischemia* ; Sensitivity and Specificity

Platelet-rich plasma (PRP) has been known to increase the rate and degree of bone formation by virtue of growth factors in concentrated platelets. Although its great healing effect on bone defect or pre-implantation site preparation in conjunction with bone substitute has been reported, the effect associated with implant is unknown. The purpose of this study was to investigate the effect of PRP on rapid osseointegration of endosseous dental implants in the rabbit tibiae. Twenty two adult female New Zealand white rabbits, weighing approximately 2.7-3.3kg, were used for this study. Twelve of the 22 animals were used for histomorphometric analysis and ten of the 22 were for removal torque test. Each animal received two implants in each tibia (two treated with PRP and two as control) and was given fluorochrome intramuscularly. For histomorphometric analysis, rabbits were divided into four groups according to the healing period. At 1 week, 2 weeks, 4 weeks and 8 weeks postoperatively, each three animals were sacrificed serially and the amount and rate of bone formation around dental implant were examined on the undecalcified sections under fluorescent microscope, polarized microscope and light microscope connected to a personal computer equipped with image analysis system. For removal torque test, rabbits were divided into two groups and removal torque tests were performed at 4 weeks, 10 weeks after implant placement. In total, 88 screw shaped, commercially pure titanium implants (Neoplant, Neobiotech, Seoul, Korea) were used in this study. Labeling pattern reflected differences of two groups in bone formation rate at each period. Histomorphometrically, PRP group showed significantly higher bone volume within threads compared to control group at 2 weeks (70.30+/-4.96% vs. 50.68+/-6.33%; P<.01) and 4 weeks (82.59+/-5.94% vs. 72.94+/-4.57%; P<.05). PRP group at 1, 2 and 4 weeks revealed similar degree of bone volume formation comparable to control group at 2, 4 and 8 weeks, respectively. On the other hand, while PRP group showed higher bone-implant contact (47.37+/-8.09%) than control group (33.16+/-13.47%) at 2 weeks, there were no significant differences between PRP group and control group for any experimental period. Removal torque values also showed no significant differences between PRP group and control group at any experimental period (P>.05). These findings imply that PRP could induce rapid, more bone formation around implant during early healing period and get faster secondary stability for reducing healing period, though it has not induced bone maturation enough to resist functional loading.
Adult ; Animals ; Bone Substitutes ; Dental Implants* ; Female ; Hand ; Humans ; Intercellular Signaling Peptides and Proteins ; Microcomputers ; Osseointegration ; Osteogenesis* ; Platelet-Rich Plasma* ; Rabbits ; Seoul ; Tibia ; Titanium ; Torque* ; Virtues

STATEMENT OF PROBLEM: The survival rate of wide diameter implants was lower than of 3.75-mm implants in some clinical researches. PURPOSE: The purpose of this study was to investigate the influence of implant diameter on the osseointegration of implants in the rabbit femoral condyle and tibial metaphyses by means of removal torque measurements and histomorphometric analysis. MATERIAL AND METHOD: Ten adult New Zealand White rabbits were used in this study. Two 3.75-mm diameter implants were inserted through one cortical layer in the tibial metaphyses and one 3.75-mm diameter implant was inserted in the femoral condyle. 5.0-mm diameter implants were inserted in the other leg in the same manner. A total of 60 implants (3.75-mm diameter implants:30 ; 5.0-mm diameter implants:30) were installed. After a healing time of 4 and 12 weeks, the peak removal torque values required to shear off the implants were recorded. From the removal torque values (Ncm) obtained, the mean shear stress (N/mm2) was calculated. And the percentage of direct bone-to-implant contact and the percentage of bone area inside the thread were measured by Kappa Image Base-metreo. The Student's t-test was undertaken for statistical analysis (p<0.05). RESULTS: The removal torque value of 5.0-mm diameter implants was higher than of 3.75-mm diameter implants (p<0.05). The difference of shear stress value between 3.75-mm and 5.0-mm diameter implants was not statistically significant (p>0.05). The percentage direct bone-to-implant contact had no statistical difference between two groups (p>0.05). The percentage of bone area inside the thread had no statistical difference between two groups (p>0.05). CONCLUSION: It is concluded that the quality of osseointegration is not influenced by increasing implant diameter.
Adult ; Humans ; Leg ; Osseointegration* ; Rabbits* ; Survival Rate ; Torque

No abstract available.
Epidermolysis Bullosa* ; Epidermolysis Bullosa, Junctional*