No abstract available.
Myocardium* ; Protein Kinase C* ; Protein Kinases*

BACKGROUND: Ischemic preconditioning(a prior short period of coronary artery occlusion) has been known to have protective effects on ischemia-induced myocardial injury. The purpose of this study was to investigate the effects of hypoxic preconditioning or ischemic preconditioning on the
Animals ; Anoxia ; Arrhythmias, Cardiac* ; Cats* ; Coronary Vessels ; Heart* ; Hypoventilation ; Ischemic Preconditioning ; Methods ; Reperfusion ; Tachycardia, Ventricular ; Thoracotomy ; Ventilation ; Ventricular Fibrillation

In the case of crush injury, the failure rate of replantation of free tissue transfer is high. Recently, the freezing of intact and repaired microarteries has been known to relieve spasm without inducing thrombosis in vivo. Therefore, the author thought that the vascular freezing of crushed vein showing only unrecognized endothelial damage after adequate debridement of a damaged vessel can also relieve spasm without inducing thrombosis and improve the patency rate of microvascular anastomosis. In this study, the process of vascular freezing was investigated in veins with acutely damaged endothelium using ethly chloride in a rat model. Two experiments were performed in 30 Sprague-Dawley rats, weighing about 250 gm. In the first experiment, a new crush model was established on the femoral vein of the rats. The degree of vessel injury was evaluated as crush energy. The proper crush energy was determined only by the endothelial damage without inducing thrombosis(0.037 J). In the second experiment, femoral veins were crushed with the energy of 0.037 J on the left side and then frozen after inflicted crush injury with the same energy on the right side. The gross and pathologic findings and patency rates were observed at postoperative day 2, 10 and 30. Patency in both the crushed and crush-freezing group was 100%. Pathlolgic findings in the crush-freezing group were more severe loss of the intima and most parts of the media, as well as cellular depopulation of the media when compared to the crushed group. Microthrombi adherent to the wall were demonstrated in several crush-freezing specimens, but the crush-freezing group showed relief of crush-induced vasopasm and endothelial regeneration. In conclusion, the freezing of microveins with acute endothelial damage relieves spasm without inducing thrombosis. Therefore, this study presents the posslbility of clinical application of vascular freezing in a case of crush injury requiring microvascualr anastomosis.
Animals ; Debridement ; Endothelium* ; Femoral Vein* ; Freezing* ; Models, Animal ; Rats* ; Rats, Sprague-Dawley ; Regeneration ; Replantation ; Spasm ; Thrombosis ; Veins

The presence of epicanthal folds in Asian eyelids is one of their unique features, in combination with the lack of supratarsal folds. Western culture has influenced many people to prefer to eliminate the prominent epicanthal fold. A number of surgical techniques have been suggested for their correction. However, difficulty with design, excessive and prominent scarring of medial canthal and nasal area, recurrence, and rigidity of application are potential problems associated with many procedures. This paper describes a epicanthoplasty with three-dimensional Z-plasty. Through epicanthal fold incision, the medial canthal tecdon is medially advanced and sutured to the periosteum of nasal bone. After the transposition of the flaps, trimming of the flap is usually required. Three-dimensional Z-plasty crates the attactive eyes. From March, 1995 to March, 1997, the technique was applied to 37 patients with epicanthal fold and was performed with or without double-fold operation. There were 34 females and 3 males with ages ranging from 17 to 30 years. Through 2 years follow-up, this techniques has delivered esthetically good results with minimal postoperative scar and could made the reduction of ICD from 40 +/- 2.13mm to 34 +/- 1.98mm. The advantages of epicanthoplasty procedure using three-dimensional Z-plasty(Yoon's method) are as follows; 1) simple in design 2) minimal postoperative scar in the medial canthal area 3) versatile in its application 4) no recurrence 5) no hypertrophic scar 6) preserving ethnic identity.
Asian Continental Ancestry Group ; Cicatrix ; Cicatrix, Hypertrophic ; Eyelids ; Female ; Follow-Up Studies ; Humans ; Male ; Nasal Bone ; Periosteum ; Recurrence

OBJECTIVE: It has been suggested that the occurrence of persistent pain signal during the early postnatal period may alter an individual's response to pain later in life. The aim of this study is to assess whether neonatal nerve injury resulted in long-lasting consequences on nociceptive system in the rat. METHODS: We examined whether neuropathic pain behaviors and the changes of spinal neuropeptides (SP, CGRP, VIP and VIP) induced by peripheral nerve injury within 1 day after birth (Neonate group) were different from those at 8 weeks after birth (Mature group). RESULTS: The Neonate group showed more robust and long-lasting pain behaviors than the Mature group. Immunohistochemical findings demonstrated that spinal SP- & CGRP-immunoreactivities(ir) of the ipsilateral to the contralateral side increased in the Neonate group, whereas those decreased in the Mature group. In addition, increase in spinal VIP- & NPY-ir of the ipsilateral to the contralateral side was more robust in the Mature group than in the Neonate group. CONCLUSION: These results suggest that peripheral nerve injury in the early postnatal period may result in long-lasting and potentially detrimental alterations in nociceptive pathways.
Animals ; Humans ; Hyperalgesia ; Infant, Newborn ; Neuralgia* ; Neuropeptides* ; Parturition ; Peripheral Nerve Injuries* ; Peripheral Nerves* ; Rats*

The present study was performed to observe the time course of behavioral signs of painful sensations in sciatic neurectomy animal model and to test the effects of sympathectomy and saphenous nerve section on these behavioral signs. Sciatic nerve was ligated and cut at the mid-thigh level under gaseous anesthesia. The application of von Frey filaments to the medial plantar surface of foot revealed weak and long-lasting mechanical allodynia (until end of test period, 20 weeks PO). Acetone application to the plantar surface of foot was used ti measure the sensitivity to cold stimulation. Cold allodynia which is interpreted as increased response to acetone application developed fairly well and lasted the end of test period (20 weeks PO). The cumulative duration of foot lifts off neutral or cold plate was used to test spontaneous, ongoing pain and was increased until 16 weeks PO and 20 weeks PO respectively. These results suggest that sciatic neurectomy which has been widely used as chronic pain model shows behavioral signs suggsting painful sensations except autotomy, which has been used as index of pain in experimental animal. Surgical sympathectomy performed 1 week after sciatic neurectomy partially reduced the behavioral signs of mechanical allodynia and cold allodynia, suggesting behavioral changes developed following section of sciatic nerve was partially sympathetic dependent. Saphenous nerve section 1 week after sciatic neurectomy almost completely reduced mechanical allodynia and cold allodynia, but did not change spontaneous, ongoing pain. These results suggest that evoked responses such as mechanical and cold allodynia are mediated by saphenous nerve activity and activating and/or maintaining mechanisms of spontanous, ongoing pain and evoked pain may be different.
Acetone ; Anesthesia ; Animals ; Chronic Pain ; Cold Temperature ; Foot ; Hyperalgesia ; Models, Animal ; Neuralgia ; Rats ; Sciatic Nerve ; Sensation ; Sympathectomy

STATEMENT OF PROBLEM: A tenderness of the dentin after tapering of teeth for dental prosthesis is a common phenomenon. In practice, the alternative desensitizer may be used for minor pain after tapering of teeth. PURPOSE: In this study, the desensitizers were used to investigate the affect decreasing of shear bond strength according to the use of various cement, such as resin, Glass Ionomer, and phosphate cement. MATERIAL AND METHOD: Three different desensitizers were used on this study. Compositions of two dentin desensitizers were HEMA(hydroxyethylmethacrylate) and glutaraldehyde. The other one is oxalic acid. Three dentin desensitizers applied on 12 degrees taper teeth. Then, Ni-Cr crowns were bonded with Resin cement, Zinc Phosphate (ZPC) cement and Glass Ionomer (GIC) cement. 120 human premolar teeth were used for specimens. The specimens were divided into four group as the reference and the empirical each with thirty specimens, then further divided into 12 group according to type of desensitizers and cement types. The shear bond strength were measured by Instron multi task instrument. RESULTS: According to the result, the measured shear bond strength in order from the weakest to the strongest in general was ZPC, Resin, and GIC. And it is found that the application of desensitizers on dentin surface does not affect the shear bond strength. CONCLUSION: Dentin desensitizers that alleviate or prevent a dentin tenderness, usually contains HEMA and glutaraldehyde compounds. Such desensitizers are widely used in clinical studies. By applying the dentin desensitizer on the exposed dentin surface, the dentin capillary are blocked and periodontal membrane and cementum can not be drawn in pulp cavity. Since HEMA and glutaraldehyde may cause harm to the pulp cavity, an alternative desensitizer was developed.
Bicuspid ; Capillaries ; Crowns ; Dental Cements* ; Dental Cementum ; Dental Prosthesis ; Dentin* ; Glass ; Glutaral ; Humans ; Membranes ; Oxalic Acid ; Resin Cements ; Tooth ; Zinc

Partial peripheral nerve injury occasionally results in neuropathic pain, including spontaneous burning pain and increased sensitivity to sensory stimuli such as hyperalgesia and allodynia. The pathophysiological mechanisms underlying this disease are poorly understood and the available treatments unsatisfactory. Presently, the neuropathic pain is believed to result from an increase in the excitability of the dorsal horn neurons (central sensitization), which is induced by abnormal signals from injured afferents. PKC-gamma is known to play a pivotal role in central sensitization following peripheral nerve injury. In the present study, we examine the expression of PKC-gamma mRNA of the spinal dorsal horn after neuropathic injury. There was no significant difference of PKC-gamma mRNA between lesion and control sides. These results suggest that PKC-gamma mRNA is not a key factor for the generation of neuropathic pain.
Animals ; Burns ; Central Nervous System Sensitization ; Horns ; Hyperalgesia ; Models, Animal* ; Neuralgia* ; Peripheral Nerve Injuries ; Posterior Horn Cells ; Protein Kinases* ; Rats* ; RNA, Messenger* ; Spinal Cord*

Although reoxygenation is the best way to salvage hypoxic tissues, reduced oxygen species (ROS) generated during reoxygenation are known to cause further tissue injuries and the induction of heat shock proteins (HSPs). The present study was undertaken to determine any causal relationship between the severity of hypoxia and the opposite outcomes, either beneficial or detrimental, of the subsequent reoxygenation by measuring the HSP72. To this aim, one group (6 male cats, 2.5 ~ 3.5 kg) was subjected to a 5-min episode of hypoventilation (H, ventilation rate: 5/min) for the induction of slight hypoxia and the other group (6 male cats, 2.4-3.7 kg) was subjected to a 5-min episode of apnea (A) for severe hypoxia. Each 3 animals from both groups received a 10-min episode of ventilation with 95% O2 (O), whereas the remainder did not. After these procedures, all animals were allowed to be ventilated within physiological range for 1, 4, or 8 hours (1H, 1HO, 4H, 4HO, 8H, 8HO, 1A, 1AO, 4A, 4AO, 8A and 8AO groups). Control animals did not receive any manipulation. The arterial blood pCO2 was significantly higher just after apnea than hypoventilation, while pO2 and pH were significantly lower just after apnea than hypoventilation. Western blot analysis revealed that the magnitude of HSP72 synthesis is larger in 1H, 4H and 8H groups than in 1HO, 4H and 8HO groups, respectively. In contrast, 1AO, 4AO and 8AO groups more induced HSP72 than 1A, 4A and 8A groups, respectively. These results suggest that the reoxygenation is beneficial after slight hypoxia but detrimental after severe hypoxia.
Animals ; Anoxia* ; Apnea ; Blotting, Western ; Cats* ; Heat-Shock Proteins ; Humans ; Hydrogen-Ion Concentration ; Hypoventilation ; Lung* ; Male ; Oxygen ; Ventilation

OBJECTIVE: To evaluate the effect of clonidine on the experimental neuropathic pain model and to observe whether neuropathic pain is related to the sympathetic nervous system in this model by reversal of allodynia with administration of epinephrine. METHOD: The neuropathic pain was produced by unilateral transection of the superior caudal trunk innervating the rat's tail. Tail withdrawal responses based on mechanical (withdrawal frequency to bending force of von Frey hair 2.0 g) and the thermal (withdrawal latency to tail immersion in a 4degrees C or 40degrees C water with a cut-off time of 15 seconds) stimuli were used. Experiments were performed two weeks after surgery when neuropathic pain had fully been developed. Experimental group by administration of clonidine was examined by tail withdrawal responses at Day 1, Day 3 and Day 5. After one week of wash-out period, reversal of allodynia by administration of epinephrine was examined by the same test. RESULTS: Clonidine significantly decreased the frequency of withdrawal with the mechanical stimuli compared with control (P<0.01), but did not significantly decrease with the cold or warm stimuli. Epinephrine tended to aggravate the mechanical allodynia, but it was not significant compared with the control. CONCLUSION: Clonidine may relieve mechanical allodynia in neuropathic pain, but the mechanism of neuropathic pain that is related to the sympathetic nervous system in this experimental model may be unreliable.
Clonidine* ; Epinephrine* ; Hair ; Hyperalgesia ; Immersion ; Models, Animal* ; Models, Theoretical ; Neuralgia* ; Peripheral Nervous System Diseases* ; Sympathetic Nervous System ; Tail ; Water