• International Journal of Molecular Medicine
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• v.45 no.2
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• pp.678-686
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• 2020

Use of bone marrow aspirate (BMA) is a clinically advantageous cell therapeutic that bypasses the need for elaborate ex vivo cell culturing. However, a low level of bone marrow-mesenchymal stem cells (BM-MSCs) in the BMA and weak survival rate of these cells post-transplantation entails an insufficient efficacy in vivo. Moreover, stem cell activity in BMA is impaired by age or background diseases. Thus, in order to enrich the BM-MSC pool and improve cell survival, novel cell preconditioning technologies are required. In this study, it has been revealed that the pretreatment of repetitive electromagnetic stimulation (rEMS) is capable of enhancing fibroblastic colony-forming units and cell proliferation in the BM-MSCs, possibly via transient nitric oxide production and extracellular signal regulated kinase 1/2 activation. Notably, this effect was more apparent in stem cells isolated from older patients than from young patients. Furthermore, the rEMS-pretreated cells showed ~53% higher cell survival, compared with the untreated cells, after cell transplantation in mice with no signs of tumorigenesis. Collectively, transient rEMS preconditioning could be utilized to enhance the activity of stem cells and thus, application of rEMS preconditioning to stem cells isolated from older patients is expected to improve the therapeutic effect of stem cells.

• Journal of Periodontal and Implant Science
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• v.8 no.1
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• pp.25.1-25.1
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• 1978

• Journal of Periodontal and Implant Science
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• v.40 no.5
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• pp.220-226
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• 2010

Purpose: This study was performed to evaluate the periodontal wound healing effect of particulate equine bone mineral on canine alveolar bone defects. Methods: Twelve adult male beagle dogs were used as study subjects. The mandibular second and fourth premolars were extracted prior to the experimental surgery, and the extraction sites were allowed to heal for 8 weeks. After periodontal probing, two-walled defects were created at the mesial and distal sides of the mandibular third premolars bilaterally, and the defects were filled with equine particulate bone with collagen membrane or bovine particulate bone with collagen membrane, or collagen membrane alone. The defects without any treatment served as negative controls. After probing depth measurement, animals were sacrificed at 10, 16, and 24 post-surgery weeks for micro-computed tomographic and histomorphometric analysis. Results: The equine particulate bone-inserted group showed significantly decreased values of probing depth and first bone contact compared to the negative control and collagen membrane alone groups at weeks 10, 16, and 24 (P<0.05). There were no significant differences in the new cementum length, newly-formed bone area, or newly-formed bone volume between equine particulate bone- and bovine particulate bone-inserted groups, both of which showed significantly increased values compared to the negative control and collagen membrane alone groups (P<0.05). Conclusions: Equine particulate bone showed significant differences in probing depth, first bone contact, new cementum length, newly formed bone area, and bone volume fraction values when compared to the negative control and collagen membrane alone groups. There were no significant differences between equine and bovine particulate bone substitutes in these parameters; therefore, we can conclude that equine particulate bone is equivalent to bovine bone for periodontal regeneration.

• Journal of Chest Surgery
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• v.29 no.7
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• pp.713-722
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• 1996

Poor long term patient survival (60% at 2 years) in lung allograft recipients are mainly due to rejection and complications associated with the use of nonspecific immunosuppressants. Better means to achieve waft acceptance is desperately needed. 1 have investigated whether mixed allogeneic chimerism in the form of bone marrow stem cell engraftment would induce donor-specific tolerance for lung allografts. Fisher (F344) and Wistar Forth (WF)rats were lethally irradiated (1100c0y) and reconstituted with a mixture of T-cell depleted syngeneic and allogeneic bone marrow (F344+WFIWF, ACI +F344- F344). After Mixed chimerism was documented by peripheral blood Ipnphocyte typing at 28 days, orthotopic left single lung transplantation was performed, using donor-s ecific or third party allografts. No immunosuppressants were administered. Graft rejection was monitored by chest rentgenography, and con- firmed by histology Mixed chimeric rats accepted lung allografts permanently, and it was not strain specific effect. Tolerance was all or none phenomenon which had nothing to do with the percentage of chimerlsm. Mixed chimeras rejected third party allografts in less than 10 days, a time course similar to that of unmanipulated controls. No acute or chronic rejection was observed in donor specific grafts more than 150 days posttransplant. These data suggest that mixed chimerism in the form of bone marrow stem cell engraftment results in stable, systemic donor-specific transplantation tolerance for lung allografts.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.62-70
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• 2005

Purpose: We compared the time how much time spent until the bone unions, when we grafted fresh frozen allograft during therapy of benign bone tumor depends on the degrees of bony unions. Materials and Methods: This study selected 29 cases, in which a curettage on the benign bone tumors was conducted and a fresh frozen allograft was transplanted. The area of the focus, the new bone formation, the recurrence of the focus and complications in the plain radiographs were observed. Results: The average time when we could find out bony unions in the radiographs is eleven weeks. The time when we could observe the unions in the radiographs are 11.4 weeks in allograft group, 10.7 weeks in allograft and autograft groups and 13.6 weeks in allograft and bone substitute. On radiologic findings, the average lesion size is 40 cm3. The time when we could find bony unions are 9.3 weeks in less than 40 $cm^3$ and 12.9 weeks in more than 40 $cm^3$. We could observe recurrences in two cases. Conclusion: The authors could get the similar results between fresh frozen allograft, allograft and autograft after curettage of benign bone tumor. We can think the ideal method which is the transplantation of autograft, but if we can’t get autograft enough, the best way which heal the defects is the transplantation of fresh frozen allograft.

• The Journal of Advanced Prosthodontics
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• v.6 no.6
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• pp.521-527
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• 2014

This case series evaluated the clinical efficacy of autogenous tooth bone graft material (AutoBT) in alveolar ridge preservation of an extraction socket. Thirteen patients who received extraction socket graft using AutoBT followed by delayed implant placements from Nov. 2008 to Aug. 2010 were evaluated. A total of fifteen implants were placed. The primary and secondary stability of the placed implants were an average of 58 ISQ and 77.9 ISQ, respectively. The average amount of crestal bone loss around the implant was 0.05 mm during an average of 22.5 months (from 12 to 34 months) of functional loading. Newly formed tissues were evident from the 3-month specimen. Within the limitations of this case, autogenous tooth bone graft material can be a favorable bone substitute for extraction socket graft due to its good bone remodeling and osteoconductivity.

• Archives of Craniofacial Surgery
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• v.24 no.5
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• pp.244-249
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• 2023

Fibrous dysplasia (FD) is a rare skeletal disorder characterized by abnormal fibro-osseous connective tissue replacing normal bone. Despite its benign behavior, craniofacial FD can cause morphological disfigurement, headache, and even blindness as a result of the produced mass effect. Surgical resection is recommended when the patient shows apparent clinical symptoms or aggravating facial asymmetry. Postoperative complications have been reported, such as hematoma, surgical site infection, abscess formation, resorption of the bone graft used for reconstruction, and recurrence. An aneurysmal bone cyst (ABC) is a rare benign bony lesion that can occur secondary to preexisting bone tumor. Secondary ABCs in craniofacial FD are extremely rare in the literature, accounting for less than 30, all of which are either case reports or series. We report an extremely rare case of symptomatic secondary ABC arising from craniofacial FD that had been misdiagnosed with abscess formation or recurrence and was surgically removed. Notably, 17 years elapsed between the primary surgery and the complication of secondary ABC. The patient underwent total removal of secondary ABC. After surgery, symptoms were relieved, with no recurrence observed during a 6-month follow-up.

• Clinical and Experimental Pediatrics
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• v.50 no.6
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• pp.519-523
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• 2007

Aplastic anemia is a rare disease, which is characterized by pancytopenia and hypocellular bone marrow without infiltration of abnormal cells or fibrosis. The incidence in Asia is higher than in the West and new cases are diagnosed at a rate of 5.1 per million pediatric populations per year in Korea. The pathophysiology is understood roughly by defective hematopoiesis, impaired bone marrow micro-environment and immune mechanism. Treatments are performed on basis of pathogenesis and selected depending on the severity. Immunosuppressive therapy with antilymphocyte or antithymocyte globulin and cyclosporine is effective in the majority of patients but has some problems including relapse or clonal evolution. Recently, there have been clinical trials of immunosuppression with hematopoietic growth factors or other drugs. Allogeneic hematopoietic stem cell transplantation (HSCT) is curative in children with severe aplastic anemia. The overall survival in HSCT from HLA-identical sibling is higher than alternative donor, including HLA matched unrelated donor or cord blood. We have to consider quality of life after HSCT because of high survival rate. However, chronic graft versus host disease and graft failure are important factors that affect the quality of life and overall survival. We need further investigation to make new regimens aimed at overcoming these risk factors and perform clinical trials.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.36-44
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• 1999

No one really doubts that the hottest area of dentistry in 21st century would most likely be 'implant'. With the support of a vast amount of research, implant has been successfully and rapidly absorbed into the field of general dentistry including private practitioners. For teeth with hopeless(or refractory) periodontitis or periapical pathosis, with no hesitation most dentists would think extraction as the sole treatment option followed by prosthodontic replacement possibly including implant. Not many dentists would take Trasplantation/Replantation as another treatment option for a particular condition. Dentistry is often more focused on 'Restoration' than 'Preservation' of natural dentition. 'Biologic Implant' is obviously much closer to the concept of 'Preservation'. Many different types of biologic implant system have been introduced to clinical dentistry so far. Many of those have failed to earn reasonable acknowledgement despite of the clinical success they brought. For some reason biologic implant has rather been alienated for long time. RPI(Ring Pin Implant) is designed to improve the prognosis and success rate of transplanted/replanted teeth. RPI is a Ti-based custom made implant system. It is fabricated either by electric casting or milling process. The major feature RPI gas is the 'ring & hole' structure. The hole should be no less than 1mm diameter to allow bone bridge formation thru it. The ring structure and bone bridge formation creates anti-torque activity, which largely increases the 'initial stability' of the transplanted/replanted teeth. It is also reported that RPI is beneficial in the aspect of resisting root resorption following replantation/transplantation procedure.

• Journal of Microbiology
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• v.39 no.3
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• pp.226-228
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• 2001

Human lymphotropic herpesvirus is known to be a major pathogen associated with various diseases in bone marrow transplantation (BMT) recipients. A multiplex nested-polymerase chain reaction (PCR) method was developed for the simultaneous detection of human lymphotropic herpesviruses, including Ebstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpesvirus 6 variants A and B (HHV6-A, HHV6-B). To demonstrate the usefulness of multiplex PCR for the analysis of clinical samples, peripheral blood mononuclear cells and serum from BMT recipients were analysed. The results skewed that a clear detection could be made between EBV, HCMV and HHV-6. This multiplex PCR assay is an efficient and cost-effective approach to the analysis of large numbers of samples to determine the epidemiological importance of EBV HCMV and HHV-6.