• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.723-731
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• 1995

Type I and type II collagens are considered the major collagens of bone and cartilage respectively. Monitoring the patterns of those gene and protein expressions during development will provide a basis for the understanding of the normal and abnormal growths. This study was undertaken to investigate the expression of collagen genes and proteins involved in the developing human mandible. Fifty embryos and fetuses were studied with Alcian blue-PAS, Masson's Trichrome, reverse transcription polymerase chain reaction (RT-PCR), Western blot analysis, and Southern blot analysis. Our results showed that $pro-{\alpha}1(II)$ collagen gene expression begins in the 5th week. Type II collagen is synthesized in mesenchymal cells in advance: of overt chondrogenesis. The gene expression for type II collagen was highest during the appearance of Meckel's cartilage. There was a switch in collagen protein expression from type I to type II during the appearance stage of Meckel's cartilage. The distribution of the mRNA for type II collagen corresponded well with the pattern of type II collagen protein. The endochondral ossification was observed where there was direct replacement of cartilage by bone.

• Korean Journal of Clinical Laboratory Science
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• v.37 no.1
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• pp.35-40
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• 2005

This paper reports the morphological nature of the remodelled interface process between implants and surrounding bone after 1, 4, 6, 8 and 12 weeks of implantation of smooth machined implants into rat tibias. After 4 weeks of implantation, histochemical analysis showed that the new bone was growing in direct contact with the implant. In the forming process, the activatived osteoblast cells migrated toward the interface and colonized the surface at the contact areas. This immature woven bone, rich in osteocyte lacunae, was deposited directly onto the implant surface. Osteoblast activity was found to continue ill 12 weeks of implantation The osteoblasts in lacunar areas developed numerous processes and synthesized bone matrix, after all, surrounded by secreting matrix. At the 12th week, the amount of newly formed bone matrix between bone and implant increased in mineralization. The mineralized mature bone contained well organized collagen fibers with characteristic banding pattern bone tissue formation around the implant.

• Journal of Periodontal and Implant Science
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• v.37 no.1
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• pp.65-75
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• 2007

In this study, author examined the effect of the concentration of the inorganic polyphosphate on the process of the bone regeneration by using the 6 weeks old rabbit with the weight of 2.0kg in average. we performed the experiment by using TR-eITFE membrane filled with collagen immersed with 1%, 2%, and 4% of inorganic polyphosphate, respectively, after removing the proper sized cort-ical bones from the calvaria of rabbit. The experimental results were compared with the one of the following four groups: The control group for membrane only, experimental group I for membrane filled with collagen im-mersed with 1% of inorganic polyphosphate, experimental group II for membrane filled with collagen immerse with 2% of inorganic polyphosphate, experimental group III for membrane filled with colla-gen immersed with 4% of inorganic polyphosphate. The fragments of the tissue with membrane were obtained from each group of the sacrificed rab-bits for 4 or 8 weeks sustained after surgery, were then prestained and coated. New bone formation was assessed by histomorphometric and statistical analysis. We may draw the conclusions from these experiments as following: 1. Collagen was an excellent carrier with a minimal inflammatory reaction and sustaining the form. 2. The sample of the 8th week group has shown the best bone regeneration compared with the cases of all groups including the control group. 3. The samples of collagen immersed with 2% and 4% of inorganic polyphosphate have shown more bone regeneration relative to the sample of the 1% inorganic polyphosphate. 4. The new bone regeneration was shown actively in the group for membrane filled with collagen immersed with 4% of inorganic polyphosphate. With above results, it is strongly suggested the use of inorganic polyphosphate with vehicle under TR-eITFE membrane.

• Journal of Life Science
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• v.19 no.12
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• pp.1841-1846
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• 2009

Menopause is often associated with the incidence of several chronic diseases including osteoporosis, cardiovascular disease, and obesity. Hormone replacement therapy (HRT) is an effective regimen that has been found to prevent these diseases in postmenopausal women. However, HRT is accompanied by an increased risk of unfavorable outcomes. Therefore, this study was conducted to evaluate the effects of Ecklonia cava, a kind of seaweed, extract on bone turnover markers in symptomatic menopausal women. For this study, the following four groups of 9-week-old Sprague-Dawley rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (OVX-CON) and ovariectomized rats that were treated with Ecklonia cava extracts. The optimum extraction temperature and solvent of Ecklonia cava were found to be $80^{\circ}C$ and 80% ethanol. We measured the osteocalcin and CTx content, enzyme ALP activity in serum and collagen content in the cartilage, bone, skin and lungs. We found that the levels of indicators of bone metabolism such as ALP, osteocalcin and CTx were lower in rats in the Ecklonia cava extract group than the OVX-CON group. In addition, the collagen contents in the bone, cartilage, skin and lungs decreased in response to ovariectomy, but the levels of collagen were greater in the bone of rats that were treated with Ecklonia cava extract than in the bone of rats in the OVX-CON group. According to these results, we were able to know the effects of Ecklonia cava extract on bone aging in ovariectomized rats. Consequently, we expect Ecklonia cava extract to have an effect on bone aging in postmenopausal women.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.111-116
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• 2007

The aim of this study was to evaluate the effect of Lycii fructus (LF) on serum lipid and the collagen content of the connective tissues in ovariectomized rats. From day 2 until day 37 after the ovariectomy, Sprague-Dawley female rats were randomly assigned to the following groups : sham-operated rat (Sham), ovariectomized control rat (OVX-control), and ovariectomized rats supplemented with the LF 50mg/kg bw/day (OVX-LF). The LF ethanol extract were orally administrated 1ml per day. Body weight gain was not significantly different in groups. Although total-cholesterol and triglyceride were increased in the ovariectomized control, supplementation with the LF extract decreased the levels. Moreover, the serum HDL-cholesterol levels were significantly increased after supplementation with the LF extract(p<0.05). Supplementation with the LF extract prevented a decrease in the collagen level in bone and cartilage tissues. These results are consistent with the conclusions based on the estrogenic activities of LF. Therefore, it may be used to possibly improve the quality of life in menopausal women.

• International Journal of Industrial Entomology and Biomaterials
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• v.34 no.2
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• pp.32-37
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• 2017

The purpose of this study was (1) to demonstrate the anti-microbial properties of 4-hexylresorcinol (4HR) loaded silk mat and (2) comparison of bone formation between 4HR incorporated silk mat and collagen membrane. Anti-microbial properties of 4HR incorporated silk mat was done after sterilization of silk mat (autoclaving and ethylene oxide gas). For the evaluation of bone formation, bilateral bony defects (size: 8 mm) were prepared in the parietal bone of the rabbits (n=10). 4HR incorporated silk mat (size: $10{\times}10mm$) was applied on the right defect. For the comparative purpose, the same size of commercial collagen membrane was applied on the left defect. The anti-microbial properties of 4HR incorporated silk mat were maintained after sterilization process. When compared bone mineral density and bone volume, there was no statistically significant difference between groups at 4 weeks and 8 weeks after operation (p>0.05). In conclusion, 4HR incorporated silk mat could be autoclaved without concern of anti-microbial properties loss. In addition, 4HR incorporated silk mat showed similar bone regeneration to collagen membrane. Therefore, 4HR incorporated silk mat might be considered for the application of open membrane technique.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.142-151
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• 2003

To induce bone formation at ectopic site by tissue engineering and gene therapy, we transplanted collagen sponges containing rhBMP-7 transduced HEK 293 cells in the hypodermis of nude mice. Bone formation was investigated by histological and electron microscopic method at 3, 6, and 9 weeks after transplantation. At 9 weeks after transplantation, eosinophilic bony tissue was observed in the implanted collagen sponge and was confirmed as bone tissue by Von Kossa stain. In the transmission electron microscopic observation, the cells in newly formed bone tissue had eccentrically located nucleus and well developed rough endoplasmic reticulum (rER). Therefore, the cells were evaluated as osteoblasts. Those results suggest that it is possible to form a bone tissue in the ectopic site by transplantation of rhBMP-7 transduced HEK 293 cells. This will be contributed to push more advanced gene therapy for bone formation. However, the HEK 293 cell is unable to apply to the clinical gene therapy. Therefore it is worth to find more compatible cells for clinical application. In addition, collagen sponge is considered as an excellent scaffold and/or carrier for gene therapy and a good biomaterial for tissue engineering.

• The Journal of the Korean dental association
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• v.52 no.4
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• pp.218-233
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• 2014

Bispbosphonates are a class of pharmaceutic agents, which induce apoptosis of osteoclast as well as impair osteoclastic activity to suppress bone resorption. Thus, bisphophonates are effectively used to treat osteoporosis, multiple myeloma and to prevent bone metastases of malignant cancer. However, recently dental disease have been reported associated with Bisphosphonates. Thus, there are a number of discussions about proper prevention and treatment of bisphosphonate-related osteonecrosis of jaw(BRONJ). Marshall R. Urist in 1965 made the seminal discovery that a specific protein, BMP(bone morphogenetic protein), found in the extracellular matrix of demineralized bone could induce bone formation newly when implanted in extraosseous tissues in a host. BMPs are multi-functional growth factors which are members of the transforming growth factor-beta super family and their ability is that plays a pivotal roll in inducing bone. About 18 BMP family members have been identified and characterized. Among of them, BMP-2 and BMP-7 have significant importance in bone development. In this study, patients of BRONJ were recieved who visited Department of oral and maxillofacial surgery, school of dentistry, Wonkwang university for past 3 years from 2011 to 2013. We focused on the results of the surgical intervention. We suggest that new strategy of treatment used to rhBMP-2 and LFA(Lidocaine-Fibrinogen-Aprotinin)-collagen scaffold for patients of BRONJ. The purpose of this paper is to give a brief overview of BMPs and to critically review the clinical data currently available on rhBMP-2 and LFA collage scaffold.

• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.475-488
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• 2002

The purpose of this study is to evaluate histologically the resorption and tissue response of various resorbable collagen membranes used for guided tissue regeneration and guided bone regeneration, using a subcutaneous model on the dorsal surface of the rat. In this study, 10 Sprague-Dawley male rats (mean BW 150gm) were used and the commercially available materials included acellular dermal matrix allograft, porcine collagen membrane, freeze-dried bovine dura mater. Animals were sacrificed at 2,6 and 8 weeks after implantation of various resorbable collagen membranes. Specimens were prepared with Hematoxylin-Eosin stain for light microscopic evaluation. The results of this study were as follows: 1. Resorption : Inner portion of porcine collagen membrane was resorbed a lot at 6 weeks, but its function was being kept for infiltration of another tissues were not observed. Freeze-dried bovine dura mater and acellular dermal allograft were rarely resorbed and kept their structure of outer portion for 8 weeks. 2. Inflammatory reactions : Inflammatory reaction was so mild and foreign body reaction didn't happen in all of resorbable collagen membranes, which showed their biocompatibility. 3. In all of resorbable collagen membranes, multinuclcated giant cells by foreign body reactions were not observed. Barrier membranes have to maintain their function for 4-6 weeks in guided tissue regeneration and at least 8 weeks in guided bone regeneration. According to present study, we can find all of the resorbable collagen membranes kept their function and structure for 8 weeks and were rarely resorbed. Foreign body reaction didn't happen and inflammatory reaction was so mild histologically. Therefore, all of collagen membranes used in this experiment were considered proper resorbable membranes for guided tissue regeneration and guided bone regeneration.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.156-162
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• 2007

Purpose: In the previous in vitro studies the bone marrow stromal cells(BSCs) have shown the superior effect for wound healing activity than fibroblasts, which includes cell proliferation, type I collagen synthesis, and the production of bFGF, VEGF and TGF-${\beta}$ in chronic wound healing. The aim of this study is to compare the effects of BSCs and fibroblasts on wound healing activity in vivo, especially on collagen synthesis. Methods: The fibroblasts and BSCs were harvested from patients and cultured. The cultured cells were infiltrated into the pores of polyethylene discs. These discs were divided into three groups according to the mixed cells. In groups I, II and III the discs were loaded with no cells, fibroblasts and BSCs, respectively. Twelve discs per group(total 36 discs) were made for this study. After creating 6 pockets in the back of each rats, each discs was implanted into each pockets. At three time intervals from 1 to 3 weeks, the implanted discs were harvested for the histological and quantitative analysis. The amount of collagen produced was evaluated using ELISA. Statistical comparisons were made using the Mann-Whitney U-test. Results: There was great difference in the collagen synthesis among the three groups by the 1st and 2nd weeks. The BSC group showed highest collagen level, followed by fibroblast group and no cell group(p<0.05). The 3rd week specimens also showed greater collagen amount in BSC and fibroblast groups compared to those of no cell group(p<0.05). However, there was little difference between BSC and fibroblast groups. Conclusion: This result demonstrates that BSC has superior effect on stimulating wound healing than fibroblast, which is currently used for wound healing.