• Journal of Periodontal and Implant Science
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• v.37 no.2
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• pp.237-249
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• 2007

This study was performed to evaluate the effect of membrane exposure on new bone formation when guided bone regeneration with perforated titanium membrane on atrophic alveolar ridge. The present study attempted to establish a GBR model for four adult beagle dog premolar. Intra-marrow penetration defects were created on the alveolar ridge(twelve weeks after extraction) on the mandibular premolar teeth in the beagle dogs. Space providing perforated titanium membrane with various graft material were implanted to provide for GBR. The graft material were demineralized bovine bone(DBB), Irradiated cancellous bone(ICB) and demineralized human bone powder(DFDB). The gingival flap were advanced to cover the membranes and sutured. Seven sites experienced wound failure within 2-3weeks postsurgery resulting in membrane exposure. The animals were euthanized at 4 weeks postsurgery for histologic and histometric analysis. The results of this study were as follows: 1. There was little new bone formation at 4 weeks postsurgery. irrespectively of membrane exposure. 2. There was significant relationship between membrane exposure and bone graft resorption(P<0.05), but no relation between membrane exposure and infiltrated connective tissue. 3. There was much bone graft resorption on DFDB than ICB and DBB. 4. The less exposure was on the perforated titanium membrane, the more dense infiltrated connective tissue was filled under the membrane when grafted with ICB and DBB. but there was no relationship between the rate of membrane exposure and the percentage of infiltrated connective tissue area and no relationship between the percentage of the area in the infiltrated connective tissue and in the residual bone graft. Within the above results, bone formation may be inhibited when membrane was exposed and ICB and DBB were more effective than DFDB as a bone graft material when guided bone regeneration.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.539-546
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• 1999

Bone is a complex tissue in which resorption and formation continue throughout life. The bone tissue contains various types of cells, of which the bone forming osteoblasts and bone resorbing osteoclasts are mainly responsible for bone remodeling. Periodontal disease represents example of abnormal bone remodeling. Osteoclasts are multinucleated cells present only in bone. It is believed that osteoclast progenitors are hematopoietic origin, and they are recruited from hematopoietic tissues such as bone marrow and circulating blood to bone. Cells present in the osteoclast microenvironment include marrow stromal cells, osteoblasts, macrophages, T-lymphocytes, and marrow cells. These cells produce cytokines that can affect osteoclast formation. In vitro model systems using bone marrow cultures have demonstrated that $IL-l{\beta},\;IL-3,\;TNF-{\alpha},$ bFGF can stimulate the formation of osteoclasts. In contrast, IL-4 inhibits osteoclast formation. Knowledge of cytokines and bFGF that affect osteoclast formation and their capacity to modulate the bone-resorbing process should provide critical insights into normal calcium homeostasis and disorders of bone turnover such as periodontal disease, osteoporosis and Paget's disease.

• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.355-362
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• 2008

Purpose: The carrier for the delivery of bone morphogenetic proteins(BMPs) should also serve as a scaffold for new bone growth. In addition, predictable bone formation in terms of the volume and shape should be guaranteed. This study evaluated the ectopic bone formation of recombinant human BMP-2(rhBMP-2) using a micro macroporous biphasic calcium phosphate (MBCP: mixture of ${\beta}TCP$ and HA) block as a carrier in a rat subcutaneous assay model. Materials and Methods: Subcutaneous pockets were created on the back of 40 male Sprague-Dawley rats. In the pockets, rhBMP-2/MBCP and MBCP alone were implanted. The blocks were evaluated by histological and histometric parameters after a healing interval of 2 weeks (each 10 rats; MBCP and rhBMP-2/MBCP) or 8 weeks (each 10 rats; MBCP and rhBMP-2/MBCP). Results: The shape and volume of the block was maintained stable over the healing period. No histological bone forming activity was observed in the MBCP alone sites after 2 weeks and there was minimal new bone formation at 8 weeks. In the rhBMP-2/MBCP sites, new bone formation was evident in the macropores of the block. The new bone area at 8 weeks was greater than at 2 weeks. There was a further increase in the quantity of new bone with the more advanced stage of remodeling. Conclusions: A MBCP block could serve as a carrier system for predictable bone tissue engineering using rhBMPs.

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.37-46
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• 1981

This study was undertaken to evaluate the pulpal responses to the pulp-capping materials such as glutaraldehyde and formocresol in pulpotomy technique, especially in the primary dentition. Mandibular primary canines and molars of 5 dogs (aged about 8-9 weeks)were selected for this study. The intervals of observation for histologic study of pulpotomized primary teeth with 2% glutaraldehyde, formocresol and calcium hydroxide in the usual manner ranged from 2 hours, 1 week, 2 weeks, 3 weeks and 5 weeks after experiments respectively. Each specimens were fixed with 10% formalin and decalcified in 5% nitric acid. All slides were stained with Hematorylin-Eosin and examined histopathologically. The results were as follows; 1. In calcium hydroxide groups, formation of dentin bridge was initiated in 1 week after experiments and completed in 5 weeks after experiments. 2. Formation of dentin bridge was not seen, whereas necrosis of pulp tissue was noted, in formocresol and glutaraldehyde groups. 3. Duration of tissue reactions and tissue changes were similar, in formocresol and glutaraldehyde groups. 4. In formocresol and glutaraldehyde groups, amputation surfaces of the pulp were covered with blood clots, beneath which coagulation necrois was noted, but inflammatory cells were not prominent, in 2 hours and 1 week after experiments. But coagulation necrosis was proceeded to the apical portion, accompanied by infiltration of inflammatory cells, since 2 weeks after experiments. And suppuration or gangrene of the pulp tissue were noted in 3 weeks and 5 weeks groups. 5. Suppuration or gangrene of pulp seemed to provoke the resorption of dentin wall, and inflammatory changes and resorption of roots were noted in the periodontal membrane near the periapical region. 6. As compared with calcium hydroxide groups, resorption of the root was pronounced in form or cresol and glutaraldehyde groups. Effects of medicaments to the succedaneous tooth germ were not seen.

• Archives of Plastic Surgery
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• v.39 no.5
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• pp.463-468
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• 2012

Background In the extremities of premature infants, the skin and subcutaneous tissue are very pliable due to immaturity and have a greater degree of skin laxity and mobility. Thus, we can expect wounds to heal rapidly by wound contraction. This study investigates wound healing of full-thickness defects in premature infant extremities. Methods The study consisted of 13 premature infants who had a total of 14 cases of full-thickness skin defects of the extremities due to extravasation after total parenteral nutrition. The wound was managed with intensive moist dressings with antibiotic and anti-inflammatory agents. After wound closure, moisturization and mild compression were performed. Results Most of the full-thickness defects in the premature infants were closed by wound contraction without granulation tissue formation on the wound bed. The defects resulted in 3 pinpoint scars, 9 linear scars, and 2 round hypertrophic scars. The wounds with less granulation tissue were healed by contraction and resulted in linear scars parallel to the relaxed skin tension line. The wounds with more granulation tissue resulted in round scars. There was mild contracture without functional abnormality in 3 cases with a defect over two thirds of the longitudinal length of the dorsum of the hand or foot. The patients' parents were satisfied with the outcomes in 12 of 14 cases. Conclusions Full-thickness skin defects in premature infants typically heal by wound contraction with minimal granulation tissue and scar formation probably due to excellent skin mobility.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.351-358
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• 2011

Purpose: The inflammatory phase is considered an integral part of adult wound healing, but fetal wound healing studies have shown scarless healing results in the absence of the inflammation process. The COX-2 pathway is an essential component of inflammation. The purpose of this study is to identify the effect of a topical selective COX-2 inhibitor on inflammation in rabbit skin wound healing and scarring. Methods: Full-thickness wounds were made on 6 New Zealand rabbits' ears. Topical 5% celecoxib + vehicle (experimental tissue) and vehicle only (controlled tissue) were applied daily for 14d on each side of the ears. Scar samples were harvested at 2 wks, 4 wks, and 8 wks after the wounding. Each sample was stained with hematoxylin and eosin and the Masson's trichrome stain to evaluate inflammation and scar formation. Results: Histological analysis demonstrated a significant reduction of inflammation, neovascularization, and scar elevation in the experimental tissue as compared to the control. Additionally, experimental tissue exhibited faster improvement of collagen organization similar to that of normal tissue. Conclusion: This study suggests that the topical application of a selective COX-2 inhibitor on a rabbit ear wound resulted in decreased inflammation and had a positive effect on the reduction of scar formation.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.485-488
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• 2010

Purpose: Paragonimiasis is infectious disease occurred by Paragonimus Westermani, which invades into human body as a final host. Habitual eating the freshwater crab or crawfish unboiled is one of the reason of infection. Paragonimiasis raged in 1970s in Korea, Japan, China and other Asian countries but the incidence decreased rapidly. Once people eat infected second host, parasite penetrates the duodenal wall and migrates to the lung. During this migration period, the parasite can migrate to other organ, such as brain, spinal cord, liver and subcutaneous tissue, but the cases are rarely reported. The objective of our study is to present our experience of the ectopic migration of parasite to the subcutaneous tissue of the abdomen, which was easily treated with excision and Praziquantel medication. Methods: A 59-year-old woman who likes eating unboiled freshwater crab was diagnosed as Paragonimiasis 15 months ago. Her symptoms were fever and cough, and she was treated with Praziquantel medication. 3 months after discharge, she visited our hospital with left pleuritic chest pain, cough with fever, and palpable mass formation on left lower quadrant of the abdomen. Wedge resection of the left lung and Praziquantel medication was maintained for a week. Nevertheless, fever persisted after the treatment. The patient received total excision of the abdominal soft tissue mass, and the fever was relieved. Results: Pathologic findings of the mass showed multiple cyst and abscess formation with crystal structure which is suspicious parts of the parasite or calcified egg shells. Uncontrolled fever was relieved after the operation, and there was no evidence of recurrent Paragonimiasis and ectopic migration for 1 year follow up period. Conclusion: Ectopic migration of Paragonimus is rare, but multiple organ can be involved. Patient with Paragominiasis who was refractory in fever control after Praziquantel medication or surgical evaluation of the lung should be considered as ectopic migration of the Paragonimiasis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.25 no.4
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• pp.350-355
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• 1999

Purpose : The purpose of this study was 1) to find nerve damage after inferior alveolar nerve transposition and 2) to examine whether the soft tissue or bone changes around the nerve produce the compression to the nerve in the healing period. Materials and Method : Inferior alveolar nerve was exposed through the bony window and the scratch was made in the bone to be thought as the inferior alveolar canal. Suture was made after the nerve was repositioned. The nerve and surrounding tissues were examined with the light microscope and the fluorescent microscope before surgery and at 1 month, 3 months, and 5 months after surgery. Results : After surgery, the epineurium was damaged and the nerve was divided to several fascicles covered with the perineurium The newly formed fibrous connective tissue and vessels were seen around fascicles. There was new bone formation. However the nerve was not compressed by the connective tissue or the new bone. Conclusion : The results of this study suggest that neurosensory disturbances after inferior alveolar nerve transposition are resulted by the direct trauma in surgery rather than the compression to the nerve by the scar or new bone formation in the healing period.

• BMB Reports
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• v.48 no.3
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• pp.184-189
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• 2015

Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2) is known to protect neurons from neurodegeneration during ischemia/reperfusion injury. We recently reported that ROS-mediated oxidative stress promotes phosphorylation of endogenous SHP-2 in astrocytes and complex formation between caveolin-1 and SHP-2 in response to oxidative stress. To examine the region of SHP-2 participating in complex formation with caveolin-1, we generated three deletion mutant constructs and six point mutation constructs of SHP-2. Compared with wild-type SHP-2, binding of the N-SH2 domain deletion mutant of SHP-2 to p-caveolin-1 was reduced greatly, using flow cytometric competitive binding assays and surface plasmon resonance (SPR). Moreover, deletion of the N-SH2 domain of SHP-2 affected $H_2O_2$-mediated ERK phosphorylation and Src phosphorylation at Tyr 419 in primary astrocytes, suggesting that N-SH2 domain of SHP-2 is responsible for the binding of caveolin-1 and contributes to the regulation of Src phosphorylation and activation following ROS-induced oxidative stress in brain astrocytes.

• Journal of Plant Biotechnology
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• v.8 no.1
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• pp.15-19
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• 2006

An efficient protocol for in vitro multiple shoot bud induction and plant regeneration from mature green cotyledon derived callus tissues of Acacia sinuata has been developed. Callus formation occurs at all the concentrations of thidiazuron (TDZ) in Murashige and Skoog's (MS) medium, but 0.6 ${\mu}M$ proved to be the best with maximum callus formation frequency. Supplementation of TDZ in combination with indole-acetic acid (IAA) in MS media accelerates shoot bud organogenesis in differentiating callus tissues with 60-70% conversion of shoot buds into shoot Most efficient shoot organogenesis was recorded when TDZ induced calli were subcultured at different concentrations of 6-benzyla-denine (BA). Optimum shoot bud induction and plant regeneration from callus was achieved when 0.6 ${\mu}M$ (TDZ) induced calli were subcultured at 3.0 ${\mu}M$ (BA) where $16.6{\pm}0.74$ shoots/unit callus on obtained. Rooting in in vitro differentiated shoots was achieved when transferred to medium containing different concentration of indole-3-butyric acid (IBA) in full & half strength MS medium. The well rooted plantlets were hardened and transferred to net house with 90% survival rate.