• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.5
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• pp.418-425
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• 2006

Purpose: This study was aimed at evaluating the histological changes of new bone and expression of osteopontin (OPN) after mandibular distraction osteogenesis. Materials and Methods: Unilateral mandibular distraction (0.5 mm twice per day for 10 days) was performed in eight adult dogs. Two animals were sacrificed at 7, 14, 28 and 56 days after completion of distraction, respectively. The distracted bones and contralateral non-distracted control bones were harvested and processed for histological and immunohistochemical examinations. Results: The new bone was arranged to tension direction after distraction osteogenesis. 7 days after distraction, numerous osteoblasts lining the immature trabecular bone and fibroblast-like cells in the fibrous intrezone were observed. 14 days after distraction, the new formed trabecular bones were thickened compared with 7 days after distraction. 28 days after distraction, the fibrous interzone was almost filled with newly calcified bone, and it was more hardened at 56 days after distraction. Increased OPN signals detected in the osteoblasts lining the trabecular bone and fibroblast-like cells in the fibrous interzone at 7 and 14 days after distraction. At 28 days after distraction, the OPN was weakly expressed in the osteoblasts, and it was not detected in all cellular components of distracted bone at 56 days later of distraction. Conclusions: After distraction osteogenesis, the distracted zone was completely calcified during the 56 days of consolidation period. In this study, the staining intensity of OPN increased in the osteoblasts and fibroblast-like cells at 7 and 14 days after distraction. The expression pattern of this protein shown here suggested that OPN play an important role in the osteogenesis during the early consolidation period.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.180-185
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• 2005

Purpose: To purpose of this study is to evaluate the clinical and radiological results of arthroscopic meniscus repair using Rapid Loc device. Materials and Methods: A retrospective study was performed on 44 cases which had been turned out longitudinal tear without degeneration. We repaired all cases with Rapid Loc device. Patients were evaluated using clinical examination, Orthopaedische Arbeitsgemeinschaft Knie (OAK) scheme, and MRI. We regarded patients with joint line tenderness, swelling or McMurray positive test as clinical failure. Results: A mean age was 33.3 years and follow-up period was average 15 months. Clinical results were excellent 15 cases(34.1%), good 20 cases(45.5%), fair 7 cases(15.9%), poor 2 cases(4.5%). MRI showed grade 115 cases(33.3%), grade II 22 cases(50%), grade III 7 cases(16.7%). Clinical failures were 8 cases and only one complication was developed. Conclusion: Rapid Loc device showed the excellent results in meniscus repair. We regard it has a lot of advantages in safety, softness, ease, ability to control tension at repair site.

• The Korean Journal of Physiology
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• v.29 no.2
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• pp.279-289
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• 1995

This study was designed 1) to develop a hypertensive animal model in which the blood pressures (BPs) of symmetric regions (right and left upper extremities) are significantly different and 2) to test the effect of BP per se on the contractility and endothelium-dependent relaxation of vascular smooth muscle. Rabbits were anesthetized with sodium pentobarbital and ventilated with room air via animal respirator. The transverse aorta was exposed through the left second intercostal space and the lumen of the aorta was narrowed partially by ligation using 3-0 silk and a probe at a point between the origins of the brachiocephalic trunk and the left subclavian artery. Four to eight weeks postoperatively, BPs were measured in the carotid artery as the high BP area (proximal to coactation site) and in the femoral artery as the low BP area (distal to coarctation site). In the animal model, pressure-overload hypertension was developed and the BP of the right subclavian artery was higher than that of the left subclavian artery. The concentrations of circulating epinephrine, norepinephrine, angiotensin I, and angiotensin II were measured. The right and left subclavian arteries and their branches were used for isometric tension recording in organ baths and their responsiveness to phenylephrine, serotonin, acetylcholine, and sodium nitroprusside were examined. The BPs of carotid and femoral artery in control animals were $116{\pm} 12/75{\pm}9\;mmHg (mean ${\pm}SEM$) and $130{\pm}16/68{\pm}9\;mmHg$ respectively, while those of carotid and femoral artery in the hypetensive animals were $172{\pm}6/111{\pm}10\;mmHg$ and 136{\pm} 4/100 {\pm}9\;mmHg$ respectively. There were no significant differences in the concentrations of circulating epinephrine, norepinephrine, angiotensin I, and angiotensin II between controls and the animal models. No significant differences were found in the vascular sensitivities to phenylephrine and serotonin between the high pressure-exposed vessels and the low pressure-exposed vessels. However, the endothelium-dependent relaxation to acetylcholine and nitroprusside-induced relaxation showed significant differences between the high pressure-exposed and the low pressure-exposed subclavian arteries. From the above results, we suggest that the contractility of vascular smooth muscle is unchanged by the elevated pressure per se. However, the endothelium-dependent relaxation to acetylcholine and the nitroprusside-induced relaxation are attenuated by pressure.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.259-265
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• 1994

To investigate the effects of protein concentration, heat treatment and pH on the foaming properties of sodium caseinate, surface tension, apparent viscosity, turbidity, foaming ability and foam stability at 1.0, 3.0, 5.0, 7.0 and 10.0% (W/V), at 55 and $65^{\circ}C$ and at pH 6.0, 7.0 and 8.0 were examined. The conditions of protein concentrations for the foaming abilities were $3.0{\sim}7.0%$ (W/V). Foam stabilities of heated sodium caseinates were worse than those of unheated sodium caseinates (control) at pH6.0 and 7.0 (p<0.05), while the heated one were better than the unheated at pH 8.0, 10.0% concentrations (p<0.05). Also foam stabilities of sodium caseinate at pH 6.0 were higher than those at pH 7.0 and 8.0. Foaming ability and foam stability were inconsistently effected by changing protein concentration, heat treatment and pH.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.434-439
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• 1993

To investigate the effects of neutral salts on the foaming properties of sodium caseinate, turbidity, surface tension, absolute viscosity, foaming ability and foam stability of the caseinate solutions(5%, w/v) with added NaF, $Na_2SO_4$, NaCl, $NaNO_3$, and NaSCN at concentrations of 0.1, 0.5, 1.0, 1.5 and 2.0 M were examined. NaCl and $NaNO_3$ improved the foaming ability compared to sodium caseinate without salt, and also $Na_2SO_4$ and NaF did the foaming ability at the concentrations of 0.1M and 0.5M, while NaSCN did not improve the foaming ability. For foaming ability optimal concentrations of the salts were 0.5, 1.5, and 1.0 M in $Na_2SO_4$, NaCl, and NaSCN, respectively. Additions of $Na_2SO_4$, NaF and $NaNO_3$ at 0.5 M concentrations improved the foam stability of sodium caseinate by 825%, 615%, and 53% compared to control, while those of NaSCN reduced foam stability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.486-493
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• 2017

This study examined the stress reaction, resilience levels, and the effects of the stress reaction on the resilience among dental hygiene students. From July 11, 2016 to July 29, 2016, questionnaires were collected from 274 dental hygiene students in several areas. The collected data were analyzed by descriptive statistics, t-test, One-way ANOVA, Pearson correlation coefficient, and multiple regression using SPSS Statistics ver.21.0. The stress reaction level of dental hygiene students was found to be 2.59 out of 5 points and the resilience level was 4.47 out of 7 points. The stress reaction and resilience showed a significant negative correlation in Fatigue, Tension, Frustration, Anger, Depression, Aggression(p>0.001), and stomatization(p>0.05). In other words, the lower the resilience, the higher the stress reaction.The factors of stress reaction influencing the resilience were depression and somatization, which explained 25.6%(R2=0.256). Therefore, to enhance the resilience of dental hygiene students, it is important to investigation the stress reaction and there should be more concern with students who have higher depression and stomatization. In addition, efforts to control the stress reaction are needed.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.6
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• pp.605-611
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• 2016

Ketamine is an anesthetic with hypertensive effects, which make it useful for patients at risk of shock. However, previous ex vivo studies reported vasodilatory actions of ketamine in isolated arteries. In this study, we reexamined the effects of ketamine on arterial tones in the presence and absence of physiological concentrations of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) by measuring the isometric tension of endothelium-denuded rat mesenteric arterial rings. Ketamine little affected the resting tone of control mesenteric arterial rings, but, in the presence of 5-HT (100~200 nM), ketamine ($10{\sim}100{\mu}M$) markedly contracted the arterial rings. Ketamine did not contract arterial rings in the presence of NE (10 nM), indicating that the vasoconstrictive action of ketamine is 5-HT-dependent. The concentration-response curves (CRCs) of 5-HT were clearly shifted to the left in the presence of ketamine ($30{\mu}M$), whereas the CRCs of NE were little affected by ketamine. The left shift of the 5-HT CRCs caused by ketamine was reversed with ketanserin, a competitive 5-$HT_{2A}$ receptor inhibitor, indicating that ketamine facilitated the activation of 5-$HT_{2A}$ receptors. Anpirtoline and BW723C86, selective agonists of 5-$HT_{1B}$ and 5-$HT_{2B}$ receptors, respectively, did not contract arterial rings in the absence or presence of ketamine. These results indicate that ketamine specifically enhances 5-$HT_{2A}$ receptor-mediated vasoconstriction and that it is vasoconstrictive in a clinical setting. The facilitative action of ketamine on 5-$HT_{2A}$ receptors should be considered in ketamine-induced hypertension as well as in the pathogenesis of diseases such as schizophrenia, wherein experimental animal models are frequently generated using ketamine.

• The korean journal of orthodontics
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• v.37 no.5
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• pp.351-363
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• 2007

The aim of this study was to evaluate pulp and periodontal changes following rapid tooth retraction by periodontal distraction after bone undermining surgery in young adult dogs. Methods: Alter extraction of second premolars, the interseptal bone mesial to the upper 3rd premolar was undermined. After activating the distraction appliance at 0.5 mm/day for six days, the dogs were sacrificed at 0, 1, 3, 5, 7, and 9 weeks during the consolidation period. Tissue changes of periodontium and pulp were evaluated radiologically, histologically, and immunohistochemically. Results: Digital subtraction radiography showed active bone formation in the stretched periodontal ligament from 0 - 4 weeks. Resorption of the alveolar bone, appearance of osteoclasts, and infiltration of inflammatory cells were observed just after the activation period at the pressure side, and distinctive bone formation was seen in the tension side of the periodontal ligament from 1 week. New bone formation was active at 1 - 3 weeks. The expression of calcitonin gene-related peptide in the experimental group was increased at the alveolar bone and pulp, and periodontal ligament at the pressure side from 0 - 1 week, and it decreased after 5 weeks to become similar to that of the control group. Conclusions: The results showed that rapid tooth movement using periodontal distraction can be new form of orthodontic tooth movement for accelerating normal bone formation.

• Journal of architectural history
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• v.12 no.1 s.33
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• pp.25-41
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• 2003

This paper is a study of Le Corbusier's trace regulateur of the 1920s, particularly its role in the design of the Villas La Roche-Jeanneret and Stein-de Monzie. It proceeds on the basis of the following three themes: first, the relation between the regulating line and the dom-ino frame; second, its status as a proportional device based not on a module system but one that defines relations; third, its function as an essential practical device in the design process. In the Villa La Roche-Jeanneret, the embedded horizontal planes of the dom-ino frame were constant, but the vortical lines of the columns were altered according to the changes in plan. Initially, a left-hand bay window formed a symmetry with the right-hand bay window, the only constant in the design process. With subsequent changes, mullion sections of the horizontal window and roof elements came to provide the reference points for the regulating line. Eventually, a regulating line different from the one that controlled the bay window and the elongated volume came to control the entrance hall of Villa La Roche, resulting in three different kinds of regulating lines in the final version. In contrast to the Villa La Roche-Jeanneret, a singular and consistent regulation line was anticipated in the earliest design stages of the Villa Stein-de Monzie. The repetition of its A:B grid and the standard $2.5m{\times}1.0m$ sliding window determined the proportions of both its plan and elevation, and thus the regulating line became 'automatic,' losing its viability as a practical tool. Though the regulating titles of the La Roche-Jeanneret look as if they were an afterthought, drawn after the design was complete, they were most active, requiring tenacity and discipline in their application. On the other hand, the seemingly 'redundant' regulating line of the Villa Stein-de Monzie gains its raison d'etre from the dom-ino frame. Its cantilevers and uninterrupted horizontal window could be used in decisive fashion because of the guarantee that the correct proportion would always be maintained. Thus we discover that Le Corbusier's discipline of the 1920s had a certain spectrum of flexibility. His 'parti' ranged from the extremely loose and malleable grid of the Villa La Roche-Jeanneret to the fixed grid of the Villa Stein-de Monzie. In different ways, these projects retain the tension between the dom-ino frame and the regulating line. For Le Corbusier, as much as the grid was an object with fixed attributes, it was also an active medium manipulated by the will of the architect.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.118-126
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• 2008

Dental fear is one of the main barriers to the use of dental services, leading patients to avoid periodical dental check-ups or treatments, thus making oral health worse, and sometimes becoming the reason that dental professionals fail control the behavior of patients. Therefore, a dental fear must be controlled carefully in order to promote oral health and effective dental treatment. This study was taken from 313 people 13 to 18 year olds to measure their levels of dental fear. After analyzing the characteristics of dental fear and its related factors, as well as other factors which influence dental fear, we acquired the following results. 1. The level of dental fear was high, compared with advanced countries with relatively good oral health. 2. The strongest physiological response experienced during a dental treatment was the tension of muscles. These dental fears were mainly related to anesthetic needles and drills. 3. Levels of dental fear became higher, the number of times for the dental services utilization had reduced, avoid regular dental examination and perceived oral disease symptoms increased. 4. One of the biggest influences on dental fears turns out to be direct painful experiences and beliefs about dentists.