• The korean journal of orthodontics
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• v.30 no.2 s.79
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• pp.197-204
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• 2000

[$K^+$]-selective ion channels were studied in excised inside-out membrane patches from human osteoblast-like cells (G292). Three classes of $K^+$channels were present and could be distinguished on the basis of conductance. Conductances were $270\pm27\;pS,\;113\pm12\;pS,\;48\pm8\;pS$ according to their approximate conductances in symmetrical 140 mM KCl saline at holding potential of -80 mV It was found that the small conductance (48 pS) $K^+$channel activation was dependent on membrane voltage. In current-voltage relationship, small conductance $K^+$channel showed outward rectification, and it was activated by the positive potential inside the membrane. In recordings, single channel currents were activayed by a negative pressure outside the membrane. The membrane pressure increased $P_{open}$ of the $K^+$ channel in a pressure-dependent manner. In the excised-patch clamp recordings, G292 osteoblast-like cells have been shown to contain three types of $K^+$ channels. Only the small conductance (48 pS) $K^+$channel is sensitive to the membrane stretch. These findings suggest that a hyperpolarizing current, mediated in part by this channel, may be associated with early events during the mechanical loading of the osteoblast. In G292 osteoblast-like cells, $K^+$channel is sensitive to membrane tension, and may represent a unique adaptation of the bone cell membrane to mechanical stress.

• Journal of Chest Surgery
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• v.36 no.9
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• pp.646-650
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• 2003

Many surgical techniques for ischemic mitral regurgitation (IMR) have been used with their excellent results and advantages. Here, we report our simple posterior annuloplasty techniques using vascular graft strip with their early results. Material and Method: Twenty two patients (13 male) underwent the operations for IMR (excluding the papillary muscle rupture) from December 2001 to January 2003. Preoperative risk factors were low ejection fraction (<35％, n=9), hypertension (n=13), diabetes (n=9), and renal failure (Cr>2.5, n=4). The wide dissection beneath the both vena cavae and interatrial groove after bicaval cannulation enabled the easy exposure of mitral valve even in the small left atrium. After eight or nine interrupted sutures in posterior annulus for anchoring the 6 mm width vascular graft strip, symmetric (n=8) or asymmetric (n=14) annuloplasty were done. Combined surgeries were CABG (n=21), Dor procedures (n=3), tricuspid valve annuloplasty (n=1), Maze operation (n=1), and aorto-right subclavian artery bypass (n=1). Result: Except for one surgical mortality, all the patients were doing well and the mean grade of regurgitation was decreased from 2.95 to 0.88, however the ejection fraction had not changed significantly just before discharge. Post-operative valve function evaluated before discharge revealed no residual regurgitation in 8 (including 1 patient with mild stenosis due to over reduction), minimal in 11, mild in 2, and mild to moderate regurgitation in 1. One patient who had ischemic cardiomyopathy and renal failure died of the arrhythmia during the hemodialysis. Conclusion: These observations suggest that the annuloplasty with vascular graft strip could be a safe and cost effective techniques for ischemic mitral regurgitation. However, the long term evaluation for the mitral valve function should be defined for the final conclusion.

• Journal of Chest Surgery
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• v.40 no.12
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• pp.837-842
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• 2007

Background: Closure of the ductus arteriosus is often delayed in premature infants, which creates a hemodynamically significant left to right shunt that exerts an adverse effect on the normal development and growth of these babies. We reviewed out experience on surgical closure of patent ductus arteriosus via axillary minithoracotomy in premature infants. Material and Method: From April 2002 to October 2006, 20 premature infants whose gestation was under 37 weeks underwent surgical closure of patent ductus arteriosus as a result of complications or contra-indications for the use of indomethacin. Their mean gestational age was 28.8+3.4 weeks, ranging from 25+3 to 34+6 weeks, and the average age at operation was $15.6{\pm}6.3$ days. The mean body weight at operation was $1,174{\pm}416\;g$, ranging from 680 to 2,100g; 16 infants were under 1,500 and 9 infants were under 1,000 g. The procedures were performed in the newborn intensive care unit via $2{\sim}3\;cm$ long axillary minithoracotomy with the infant in the lateral position with left arm abduction. The mean size of the patent ductus arteriosus was $3.8{\pm}0.3\;mm$. For the most part, the ductus was closed with clips; 2 infants in whom the ductus was ruptured while dissection was being performed underwent ductal division. Result: Ten of twelve infants who had been ventilator dependent preoperatively could be successfully weaned from the ventilator at a mean duration of 9.7 days after the operation. There was no procedure-related complication or death. Two infants eventually died of the conditions not related to the operation; one from sepsis at postoperative 131 days and the other from pneumonia at postoperative 41 days, respectively. Conclusion: Surgical closure of the patent ductus arteriosus improved the hemodynamic instability and so promoted the successful growth and normal development of premature infants. Considering the low surgical risk along with the reduced invasiveness, early and aggressive surgical intervention is highly recommended.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.347-352
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• 1999

Background: The atrial fibrillation in patients with mitral valvular heart disease is frequently converted to sinus rhythm after the mitral valve surgery. This sinus restoration implies an important meaning in that it not only helps postoperative convalescence in patients with unstable hemodynamics but also reduces the rate of postoperative thromboembolism. Material and Method: We retrospectively analyzed 184 patients who received mitral valve surgery from June 1986 to December 1996 to investigate the trend of rhythm change following mitral valve surgery and thus to clarify the predisposing factors of postoperative sinus rhythm conversion and its maintenance. Result: The sinus rhythm was restored after the operation in 54 out of 139 patients with atrial fibrillation preoperatively(38.8%). However, the atrial fibrillation recurred in 41 patients at the time of discharge showing a recurrence rate of 75.9 percent. The mean duration of sinus rhythm in patients with eventual atrial fibrillation recurrence was 8.2${\pm}$5.9 days. Only 15 patients were in sinus rhythm at the time of late follow-up with the mean follow-up period of 84.4${\pm}$34.7 months. While the age, duration of symptoms, duration of atrial fibrillation, left atral size, and pulmonary artery pressure were thought to be the predisposing factors for sinus conversion after the operation, only the duration of atrial fibrillation and ejection fraction were considered risk factors for the recurrence of the atrial fibrillation following sinus conversion. Conclusion: This study suggests that the early operation is mandatory for the satisfactory result regarding postoperative rhythm. Moreover, additional operative measure in adjunct to the intervention of mitral valve should be considered for the maintenance of restored sinus rhythm as reflected by high postoperative recurrence rate of atrial fibrillation.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.358-363
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• 1999

Background: Recently, many cardiac centers have been using aprotinin to reduce operative bleeding in cardiac operations using cardiopulmonary bypass. A variety of reports have confirmed the effectiveness of the drug in cardiac operations. In addition to the operations which could be considered to cause severe operative bleeding such as redo operation, long cardiopulmonary bypass operation and etc, the use of aprotinin is increasing in the field of primary cardiac operations. Varying doses of regimen have been introduced since the first report by Royston et al, and also various opinions on the effectiveness and safeness of the each regimen have been reported. We reviewed our own experience of the full dose aprotinin regimen(Hammersmith regimen) retrospectively. Material and Method: From October 1994 to February 1998, 40 cases of cardiac operative patients were randomized into two groups: aprotinin group(20 patients) which received a full dose aprotinin regimen and control group(20 patients) which did not receive aprotinin. To evaluate the degree of bleeding decrease, we analysed and compared the amount of postoperative 6 hours and 24 hours bleeding in the each group. To confirm the renal dysfunction, we measured the postoperative creatinine level. Result: In the amount of postoperative 6 hours bleeding, a statistically significant bleeding decrease was demonstrated in the aprotinin group compared to the control group(aprotinin group: 186${\pm}$40cc, control group:409${\pm}$69cc, P=0.010). Similar result was observed in the postoperative 24 hours(aprotinin group:317${\pm}$53cc, control group: 671${\pm}$133cc, P=0.024). Conclusion: We concluded that full dose regimen of aprotinin can remarkably reduce postoperative bleeding in cardiac operations without significant renal dysfunctions.

• Journal of Chest Surgery
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• v.37 no.8
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• pp.672-683
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• 2004

Background: The treatment results of the advanced lung carcinoma is not satisfactory with the present therapeutic modalities: surgical resection, anti-cancer chemotherapy, and radiotherapy or combination therapy. To predict the prognosis of the non-small-cell lung carcinoma, TNM classification has been was as the basic categorization; however, it has been not satisfactory. It is necessary to consider the causes and the prognosis of the lung carcinoma from another points of view rather the conventional methods. We intended to find out the relationship between the major apoptotic factor, p53 gene and the prognosis of the patient with lung carcinoma. Material and Method: Three hundreds and fifty-nine patients with lung carcinoma who underwent surgery were analysed. We observed p53 protein accumulated in the cellular nuclei. The p53 protein was detected by immuno-histo-chemical method. We collected information of the patient retrospectively. Result: p53 protein densities were observed in 40% in average as a whole. The protein density was 44 percent in man, 25 percent in woman, 49 percent in the squamous cell carcinoma, and 38 percent in the adenocarcinoma. There were significant correlations between the p53 protein density and the mortality in the squamous cell carcinoma (p=0.025), follow-up duration in TNM stage I group (p=0.010), and follow-up duration in the lobectomy patient group (p=0.043), and tumor cell differentiation (p=0.009). p53 protein densities were significantly different between the lobectomy and the pneumonectomy group (p=0.044). Conclusion: The authors found that p53 protein had some correlations with the prognosis of the lung cancer partially in some factors. We suggest the p53 protein density could be used as a marker of prognosis in the non-small-cell lung carcinoma.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.4
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• pp.204-213
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• 2023

Invasive or non-invasive reduction of fractures could be conducted as treatments of traumatic maxillofacial bone fractures. But when suboptimal reduction or malunion of maxillofacial bone fracture occurs, malocclusion could occur as a result of the lost relationship of the mandible and midface. This malocclusion is called post-traumatic malocclusion and orthognathic surgery, orthodontic treatment, selective grinding and prosthetic reconstruction are suggested as treatments for post-traumatic malocclusion after securement of stable TMJ. Stable TMJ is essential for occlusal rehabilitation to prevent occlusal change and relapse of malocclusion. Centric relation and adapted centric posture are suggested as start points of occlusal rehabilitation because they are most stable TMJ position. This case report presents a case in which post-traumatic malocclusion occurred after reduction of panfacial fracture. To rehabilitate full mouth occlusion, selective grinding and prosthetic reconstruction of implant supported fixed prostheses were conducted in centric relation and showed satisfying results in functional and occlusal aspects.