• Journal of the korean academy of Pediatric Dentistry
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• v.7 no.1
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• pp.75-83
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• 1980

Rickets is not the deposite of minerals in the skeletal tissue and the retardation of skeletal growth in growing in growing animals. This study was undertaken to investigate the histologic effects of experimental rickets on the dental structure of the albino rats, and to show the relationship between the histological effects and the pulpal disease which induced premature loss of the primary teeth. This study was based on material obtained from 40 white rats that were placed on a rachitogenic diet for a period 1 to 56 days after weaning (at 24 days). In addition, a study was made of 25 litter mates, 24 to 80 days, that were fed a normal diet. The following results were obtained: 1. Enamel formation and calcification showed no significant changes and no hypoplasia. 2. Dentin formation and calcification was retarded and disturbed. In the experimental group, predentin/calcified dentin was remarkablly increased. 3. Newly formed dentin showed interglobular texture (less homogenous calcification) and the predentin was significantly wider and thicker, and there was an irregular wave in the basal portion of the rat's incisors. 4. In cementum, Matrix formed at almost a normal rate but calcification was defective. So cementoid tissue was increasesd. 5. The formation of the alveolar bone was at almost a normal rate but calcification was retarded. The trabecular bone was filled with osteoid tissue and thicker than in normal groups.

• Restorative Dentistry and Endodontics
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• v.12 no.2
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• pp.101-108
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• 1987

The purpose of this study was to investigate the pulpal responses of dental adhesive resins. A total of 40 cavities of the permanent healthy teeth from 4 dogs were prepared. In the experimental group, the cavities were etched for 1 minute with citric acid and filled with experimental resins (ie. Super-Bond C & B$^{(R)}$). In the control group, the cavities were filled with calcium hydroxide base materials (ie. Dycal$^{(R)}$) without etching. The dogs were sacrificed at one, two, three and four weeks after the time of filling and the specimens were routinely prepared and stained with Hematoxylin-Eosin. The microscopic findings were as follows: Infiltration of inflammatory cells was not observed in both experimental and control groups. Change in the odontoblastic layer was not observed in all control groups but severe swelling was observed in deep dental pulp tissue of the control two and three week cases. Pulp tissue was recovered with plenty of fibrous component in the control four week case and reparative dentin formation was not occurred in all cases. Slight changes of the odontoblastic layer beneath the cavity were observed in the experimental one week case. In experimental two and three week cases, swelling of deep pulp tissue was increased and localized reparative dentin formation was observed. In the experimental four week case, odontoblastic layer was recovered with regular appearance and fibrous component of the pulp was increased, but reparative dentin formation was not evident.

• BMB Reports
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• v.55 no.10
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• pp.500-505
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• 2022

Uncoupling protein 2 (Ucp2) was first introduced as a member of Uncoupling protein family and a regulator of ROS formation; however, its role in adipose tissue is not fully understood. In the present study, we have investigated the role of Ucp2 against high-fat diet (HFD)-induced obesity in epididymal white adipose tissue (eWAT) and browning of inguinal white adipose tissue (iWAT). Diet-induced obesity is closely related to macrophage infiltration and the secretion of pro-inflammatory cytokines. Macrophages surround adipocytes and form a crown-like-structure (CLS). Some reports have suggested that CLS formation requires adipocyte apoptosis. After 12 weeks of HFD challenge, Ucp2 knockout (KO) mice maintained relatively lean phenotypes compared to wild-type (WT) mice. In eWAT, macrophage infiltration, CLS formation, and inflammatory cytokines were reduced in HFD KO mice compared to HFD WT mice. Surprisingly, we found that apoptotic signals were also reduced in the Ucp2 KO mice. Our study suggests that Ucp2 deficiency may prevent diet-induced obesity by regulating adipocyte apoptosis. However, Ucp2 deficiency did not affect the browning capacity of iWAT.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.16 no.3
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• pp.231-238
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• 1994

Tissue expansion has now been widely used in various soft tissue defects and deformities. It is to reconstruct the lesion site by providing donor tissue of the same color, texture, and similar thickness and sensation with minimal scar formation and minor donor site morbidity. It is achieved through using a temporary expander capable of accumulating normal saline. Internal pressure from expander exerts its force on the flap, which gradually expands to provide additional tissue for reconstruction. We have applied tissue expander in three patients. The first case was soft tissue loss on the left forehead. The second case was multiple scar formation on the left mandibular angle and upper cervical area. The third case was scar contraction on the right cheek. All cases have been successfully reconstructed without complications.

• Restorative Dentistry and Endodontics
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• v.6 no.1
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• pp.27-35
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• 1980

This study was to evaluate the effectiveness of a few disinfectant on amputated pulps of domestic dogs. The materials employed for the purpose were zinc oxide eugenol paste, calcium hydroxide as control groups and guaiacol (1%, 5%, 10% by weight) added zinc oxide eugenol paste and formaldehyde (1%, 5%, 10% by weight) added calcium hydroxide as experimental groups. Following were the results obtained throngh histo-pathological examination. 1) In calcium hydroxide-formaldehyde groups, secondary dentin formation was observed in the 2 weeks, but the remaining pulp tissue was severely atrophied according to the concentration of formaldehyde and the time increased. 2) In zinc oxide eugenol-guaiacol groups, the first evidence of secondary dentin formation was observed in the 3 weeks. It seems that the concentration variety of guaiacol influenced very little to the potential ability of dentin formation. 3) Except 1% formaldehyde containing calcium hydroxide group, every group showed severe pulp degeneration. In all groups of zinc oxide eugenol-guaiacol cases revealed the tendency of recovery.

• BMB Reports
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• v.42 no.4
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• pp.189-193
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• 2009

During development lymphoid tissue inducer (LTi) cells are the first hematopoietic cells to enter the secondary lymphoid anlagen and induce lymphoid tissue neogenesis. LTi cells induce lymphoid tissue neogensis by expressing a wide range of proteins that are associated with lymphoid organogenesis. Among these proteins, membrane-bound lymphotoxin (LT) $\alpha1\beta2$ has been identified as a critical component to this process. LT$\alpha1\beta2$ interacts with the LT$\beta$-receptor on stromal cells and this interaction induces up-regulation of adhesion molecules and production of chemokines that are necessary for the attraction, retention and organization of other cell types. Constitutive expression of LT$\alpha1\beta2$ in adult LTi cells can result in the formation of a lymphoid-like structure called tertiary lymphoid tissue. In this review, we summarize the function of fetal and adult LTi cells and their involvement in secondary and tertiary lymphoid tissue development in murine models.

• Fibers and Polymers
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• v.2 no.2
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• pp.51-57
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• 2001

Tissue engineering is one exciting approach to treat patients who need a new organ or tissue. A critical element in this approach is the polymer scaffold, as it provides a space for new tissue formation and mimics many roles of natural extra-cellular matrices. In this review, we describe several design parameters of polymer matrices that can significantly affect cellular behavior, as well as various polymers which are frequently used to date or potentially useful in many tissue engineering applications. Interactions between cells and polymer scaffolds, including specific receptor-ligand interactions, physical and degradation feature of the scaffolds, and delivery of soluble factors, should be considered in the design and tailoring of appropriate polymer matrices to be used in tissue engineering applications, as these interactions control the function and structure of engineered tissues.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.673-691
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• 2003

The current interest in periodontal tissue regeneration has lead to research in bone graft, root surface treatments, guided-tissue regeneration, and the administration of growth factors as possible means of regenerating lost periodontal tissue. Several studies have shown that a strong correlation between platelet-rich plasma and the stimulation of remodeling and remineralization of grafted bone exists, resulting in a possible increase of 15-30% in the density of bone trabeculae. The purpose of this study was to study the histopathological correlation between the use of platelet-rich plasma and a bone xenograft used in conjunction with a non-resorbable guided-tissue membrane, e-PTFE, compared to a control group with regards to bone regeneration at the implant fixture site. Implant fixtures were inserted and graft materials placed into the left femur of in the experimental group, while the control group received only implant fixtures. In the first experimental group, platelet-rich plasma and BBP xenograft were placed at the implant fixture site, and the second experimental group had platelet-rich plasma, BBP xenograft, and the e-PTFE membrane placed at the fixture site. The degree of bone regeneration adjacent to the implant fixture was observed and compared histopathologically at 2 , 4, and 8 weeks after implant fixture insertion. The results of the experiment are as follows: 1. The rate of osseointegration to the fixture threads was found to be greater in the first experimental group compared to the control group. 2. The histopathological findings of the second experimental group showed rapid resorption of BBP with subsequent new bone formation replacing the resorbed BBP. 3. The second experimental group showed new bone formation in the area adjacent to the fixture threads beginning two weeks after fixture implantation, with continued bone remodeling in the areas mesial and distal to the fixture. 4. Significant new bone formation and bone remodeling was observed in both experimental groups near the implant fixture sites. 5. The rate of osseointegration at the fixture threads was greater in the second experimental group compared to the first group, and the formation of new bone and trabeculae around the fixture site occurred after the fourth week in the second experimental group. The results of the experiment suggest that a greater degree of new bone formation and osseointegration can occur at the implant fixture site by utilizing platelet-rich plasma and bone xenografts, and that these effects can be accelerated and enhanced by concurrent use of a non-resorbable guided tissue membrane.

• Journal of Life Science
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• v.24 no.5
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• pp.573-587
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• 2014

Angiogenesis, the formation of new capillary blood vessels, is a tightly regulated process. Under normal physiological conditions, angiogenesis only takes place during embryonic development, wound healing, and female menstruation. Dysregulation of angiogenesis is associated with many diseases, such as cancer, rheumatoid arthritis, psoriasis, and proliferative retinopathy. The growth and expansion of adipose tissue require the formation of new blood vessels. Adipose tissue is probably the most highly vascularized tissue in the body, as each adipocyte is surrounded by capillaries, and the angiogenic vessels supply nutrients and oxygen to adipocytes. Accumulating evidence shows that capillary endothelial cells communicate with adipocytes via paracrine signaling pathways, extracellular components, and direct cell-cell interactions. Activated adipocytes produce multiple angiogenic factors, including VEGF, FGF-2, leptin, and HGF, which either alone or cooperatively stimulate the expansion and metabolism of adipose tissue by increasing adipose tissue vasculature. Recently, it was demonstrated that antiangiogenic herbal Ob-X extracts and Korean red ginseng extracts reduce adipose tissue mass and suppress obesity by inhibiting angiogenesis in obese mice. Thus, angiogenesis inhibitors provide a promising therapeutic approach for controlling human obesity and related disorders.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.526-530
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• 2010

Purpose: With the recent recognition of the importance of soft-tissue fillers, fat grafting has been assumed an increasingly important role as both an adjunctive and a primary procedure in aesthetic and reconstructive surgery. The main problem in achieving long-term soft-tissue augmentation is partial absorption of the injected fat and hence the need for overcorrection and re-injection. The purpose of this study is to improve the viability of the injected fat by the use of Lipo-PGE1. Methods: Human adipose tissue, obtained by suctionassisted lipectomy, was re -injected into the subcutaneous layer in the scalp of ICR mice. Lipo-PGE1 ($0.5{\mu}g$/kg) was injected intravenously in experimental group for 7 days from the operation day and saline was injected in control group. There were 5 animals in each group. The animals were euthanized 4 weeks after the procedure. Graft weight and volume were measured and histologic evaluation was performed. Result: Histologic analysis demonstrated significantly less cyst formation and less inflammatory reaction in the group treated with Lipo-PGE1. No significant difference was found between the groups regarding graft volume or the other histologic parameters investigated. Significant differences were demonstrated in microvascular density count. Conclusion: Less cyst formation, less inflammation, more angiogenesis indicating improved quality of the injected fat can be obtained by the addition of Lipo-PGE1. Further studies of various dosages of Lipo-PGE1 and their long-term effect are required before these encouraging results could be applied clinically.