• Journal of Periodontal and Implant Science
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• v.46 no.3
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• pp.152-165
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• 2016

Purpose: This study investigated the effects of bone density and crestal cortical bone thickness at the implant-placement site on micromotion (relative displacement between the implant and bone) and the peri-implant bone strain distribution under immediate-loading conditions. Methods: A three-dimensional finite element model of the posterior mandible with an implant was constructed. Various bone parameters were simulated, including low or high cancellous bone density, low or high crestal cortical bone density, and crestal cortical bone thicknesses ranging from 0.5 to 2.5 mm. Delayed- and immediate-loading conditions were simulated. A buccolingual oblique load of 200 N was applied to the top of the abutment. Results: The maximum extent of micromotion was approximately $100{\mu}m$ in the low-density cancellous bone models, whereas it was under $30{\mu}m$ in the high-density cancellous bone models. Crestal cortical bone thickness significantly affected the maximum micromotion in the low-density cancellous bone models. The minimum principal strain in the peri-implant cortical bone was affected by the density of the crestal cortical bone and cancellous bone to the same degree for both delayed and immediate loading. In the low-density cancellous bone models under immediate loading, the minimum principal strain in the peri-implant cortical bone decreased with an increase in crestal cortical bone thickness. Conclusions: Cancellous bone density may be a critical factor for avoiding excessive micromotion in immediately loaded implants. Crestal cortical bone thickness significantly affected the maximum extent of micromotion and peri-implant bone strain in simulations of low-density cancellous bone under immediate loading.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.1
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• pp.85-92
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• 2005

Reconstruction of defect in the anterior part of the maxilla to enable implant placement or prothesis is a complicated treatment due to the anatomical position and lack of soft tissues. Two cases are presented in which autogenous iliac PMCB(particulate marrow and cancellous bone) with titanium mesh were used for premaxilla reconstruction and alveolar bone repair of the anterior maxillas prior to denture and implants fixation respectively. Cancellous bone from the anterior iliac crest was compressed and placed against a titanium mesh fixed to the bone of palate in a patient with severe defect of the anterior maxilla. There were no problem in the healing, and the anterior maxillas of two patients had increased height and width during the initial healing and remodeling. The clinical reports describe the use of titanium mesh for reconstruction of premaxilla. Autogenous bone grafts were harvested from the iliac crest and were loaded on a titanium mesh that were left in the patient's maxilla for 6 months before they were removed respectively. The radiographic analysis demonstrated that a 10mm vertical ridge augmentation had been achieved. In guided bone regeneration, the quantity of bone regenerated under the barrier has been demonstrated to be directly related to the amount of the space under the membrane. This space can diminish as a result of membrane collapse. To avoid this problem which involved the use of a titanium mesh barrier to protect the regenerating tissues and to achieve a rigid fixation of the bone segments, were used in association with autologous bone in 2 cases. The aim of this study was to evaluate the capability of a configured titanium mesh to serve as a mechanical and biologic device for restoring a vertically defected premaxilla.

• Journal of Periodontal and Implant Science
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• v.46 no.5
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• pp.291-302
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• 2016

Purpose: The aim of the present study was to evaluate the effectiveness of using a mineralized bone cortical allograft (MBCA), with or without a resorbable collagenous membrane derived from bovine pericardium, on alveolar bone remodeling after immediate implant placement in a dog model. Methods: Six mongrel dogs were included. The test and control sites were randomly selected. Four biradicular premolars were extracted from the mandible. In control sites, implants without an allograft or membrane were placed immediately in the fresh extraction sockets. In the test sites, an MBCA was placed to fill the gap between the bone socket wall and implant, with or without a resorbable collagenous membrane. Specimens were collected after 1 and 3 months. The amount of residual particles and new bone quality were evaluated by histomorphometry. Results: Few residual graft particles were observed to be closely embedded in the new bone without any contact with the implant surface. The allograft combined with a resorbable collagen membrane limited the resorption of the buccal wall in height and width. The histological quality of the new bone was equivalent to that of the original bone. The MBCA improved the quality of new bone formation, with few residual particles observed at 3 months. Conclusions: The preliminary results of this animal study indicate a real benefit in obtaining new bone as well as in enhancing osseointegration due to the high resorbability of cortical allograft particles, in comparison to the results of xenografts or other biomaterials (mineralized or demineralized cancellous allografts) that have been presented in the literature. Furthermore, the use of an MBCA combined with a collagen membrane in extraction and immediate implant placement limited the extent of post-extraction resorption.

• Biomedical Science Letters
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• v.23 no.3
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• pp.230-237
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• 2017

Changes in the activity of alkaline phosphatase (ALP) isoenzymes and isoforms in human serum have a major diagnostic value, therefore the regulation of ALP activities is a valuable target for therapeutic interventions. To assess the pharmacological activity of retinoids, i.e., all-trans retinoic acid and 13-cis retinoic acid, their tissue-specific inhibitory effect on human serum ALP activity was elucidated by chemical inhibition methods, heat-sensitive inactivation, and wheat-germ lectin precipitation test. Retinoids showed significant inhibition of the total ALP activity in human serum at a concentration of 5 mM. All-trans retinoic acid (5 mM) and 13-cis retinoic acid (5 mM) inhibited ALP activities by up to 12% and 15%, respectively, compared to that by guanidine hydrochloride (200 mM). L-phenylalanine (100 mM) and urea (30 mM) had no further inhibitory effect on ALP activities in human serum pretreated with retinoids (5 mM). Retinoids significantly inhibited ALP activities by up to 20% compared with that of tetramisole (30 mM). The ALP activities in retinoid-pretreated serum remained unchanged after the heat inactivation process. These results suggest that retinoids are inhibitors of the intestinal ALP isoenzyme. Remarkably, retinoids revealed potent inhibitory activities against ALP in wheat-germ lectin precipitant serum, indicating that they also function as inhibitors of the bone ALP isoform. The results show that retinoids inhibit the specific tissue-derived human serum ALP activities, moreover, the inhibitory effect of retinoids against bone ALP activity suggests their clinical utility as monitoring and prevention of metastasis of bone cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6501-6506
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• 2015

There are numerous clinical cases indicating that long-term use of bevacizumab may increase the invasiveness of tumors. However, to date, little is known about underlying molecular mechanisms. Therefore, the purpose of our study was to investigate effects of bevacizumab in four cancer cells lines (WSU-HN6, CAL27, Tca83, and HeLa). It was found to promote migration and invasion in the WSU-HN6 and Tca83 cases, while exerting inhibitory effects in CAL27 and HeLa cells. The signal transducer and activator of transcription (STAT) 3 inhibitors niclosamide and S3I-201 inhibited the STAT3 signal pathway, which is activated by bevacizumab. These inhibitors also substantially blocked bevacizumab-induced migration of WSU-HN6 and Tca83 cells. Bevacizumab upregulated interleukin (IL)-6 and phosphorylated (p)-STAT3 expression time-dependently. Therefore, we propose that bevacizumab has differential effects on the migration of different cancer cell lines and promotes migration via the IL-6/STAT3 signaling pathway.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.100-105
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• 2007

Cockayne syndrome is a rare autosomal recessive disorder characterized by cachectic dwafism, mental retardation, loss of facial subcutaneous adipose tissue, microcephaly and photosensitive dermatitis. It is associated with renal abnormalities characterized by hyalinization of glomeruli, atrophy of tubules and interstitial fibrosis. To our knowledge, this is the first report of a case of Cockayne syndrome with FSGS in Korea. A 7-year old boy was admitted for evaluation of hypertension and proteinuria, which were detected 2 month ago. He was followed for short stature(<3 percentile), mental retardation(IQ 55), strabismus and dental caries since 3 years ago. He also showed microcephaly, a bird-like face and relatively large hands and feet. Laboratory findings showed decreased creatinine clearance($C_{Cr}$ 76.1 mL/min/$1.73m^2$) and proteinuria(1,548 mg/day). Renal biopsy demonstrated focal segmental glomerulosclerosis of the hilar type with large hyaline deposits, moderate tubular atrophy and interstitial fibrosis. His cardinal features, mental retardation, and renal biopsy findings were consistent with Cockayne syndrome. We report here a very rare case of Cockayne syndrome with FSGS presenting with proteinuria and hypertension.

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2141-2147
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• 2016

As one of the most complex human-associated microbial habitats, the oral cavity harbors hundreds of bacteria. Halitosis is a prevalent oral condition that is typically caused by bacteria. The aim of this study was to analyze the microbial communities and predict functional profiles in supragingival plaque from healthy individuals and those with halitosis. Ten preschool children were enrolled in this study; five with halitosis and five without. Supragingival plaque was isolated from each participant and 16S rRNA gene pyrosequencing was used to identify the microbes present. Samples were primarily composed of Actinobacteria, Bacteroidetes, Proteobacteria, Firmicutes, Fusobacteria, and Candidate phylum TM7. The ${\alpha}$ and ${\beta}$ diversity indices did not differ between healthy and halitosis subjects. Fifteen operational taxonomic units (OTUs) were identified with significantly different relative abundances between healthy and halitosis plaques, and included the phylotypes of Prevotella sp., Leptotrichia sp., Actinomyces sp., Porphyromonas sp., Selenomonas sp., Selenomonas noxia, and Capnocytophaga ochracea. We suggest that these OTUs are candidate halitosis-associated pathogens. Functional profiles were predicted using PICRUSt, and nine level-3 KEGG Orthology groups were significantly different. Hub modules of co-occurrence networks implied that microbes in halitosis dental plaque were more highly conserved than microbes of healthy individuals' plaque. Collectively, our data provide a background for the oral microbiota associated with halitosis from supragingival plaque, and help explain the etiology of halitosis.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.2
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• pp.89-98
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• 2018

Purpose : This study was designed to examine the blood glucose control and increase immunity effects of ${\beta}-glucan$ added cooked barley noodle in streptozotocin-induced diabetes mice with a high-fat diet. Method : Forty-eight male ICR mice (6-week-old) were fed AIN-93 diet for 4 weeks. Mice were divided into six groups: normal, diabetic, cooked barley noodle, ${\beta}-glucan$ (5 %) control and two experimental groups (${\beta}-glucan$ 2.5 % and 5 %, cooked barley noodle contained diet with ${\beta}-glucan$ 2.5 % and 5 % w/w). Diabetes mellitus was induced by intraperitoneal injection of streptozotocin (150 mg/kg). Result : Blood glucose level was significantly decreased in groups consuming cooked barley noodles, but no significant difference was exhibited in diabetic and ${\beta}-glucan$ control group. These results were in accordance with the result of oral glucose tolerance test. Blood interfereon $(IFN)-{\gamma}$ was measured in order to identify increase immunity effect of ${\beta}-glucan$ in diabetic mice. Inhibited $IFN-{\gamma}$ concentration was recovered in cooked barley noodle and ${\beta}-glucan$ control group. Moreover, $IFN-{\gamma}$ concentration was dramatically elevated in ${\beta}-glucan$ contained cooked barley noodle groups in a dose dependent manner. Streptozotocin induced AST and ALT activities were decreased in ${\beta}-glucan$ contained cooked barley noodle groups with a strong lipid lowering effect. Conclusion : Although addition of ${\beta}-glucan$n did not give any significant synergistic effect on cooked barley noodle in blood glucose regulation, suppressed $IFN-{\gamma}$ production by STZ was dramatically enhanced by ${\beta}-glucan$ supplementation in a dose dependent manner. Liver function and blood lipid profile were also in accordance with the increase immunity effect of ${\beta}-glucan$. Consequently, ${\beta}-glucan$ added cooked barley noodle can be consumed as good diets for patients with chronic diseases with reduced immunity.

• Pediatric Infection and Vaccine
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• v.25 no.2
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• pp.107-112
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• 2018

Staphylococcus aureus is now a major community-acquired pathogen worldwide, notably associated with skin and soft tissue infections. Staphylococci are present in the form of colonizers or environmental contaminants at home and increase the risk of recurrent infection. We are describing recurrent familial furunculosis caused by Panton-Valentine Leukocidin-positive methicillin susceptible S. aureus ST1 in Korea. An infant, his father and mother had furunculosis due to methicillin-sensitive S. aureus (MSSA) infection with identical susceptibility patterns. ST1 accounted for all 3 isolates and they were confirmed of having agr group I. Both sec and seh were detected in all isolates using polymerase chain reaction (PCR) assays, and all isolates contained Panton-Valentine leukocidin (PVL) genes. Risk factors for the household spread of S. aureus include skin conditions and close physical contact among household members. The relationship between S. aureus colonization of household contacts and the occurrence of S. aureus infection should be studied into more detail.

• Macromolecular Research
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• v.17 no.9
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• pp.703-708
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• 2009

Silk fibroin scaffolds were examined as a biomaterial option for tissue-engineered cartilage-like tissue. In tissue engineering for cartilage repair using a scaffold, initial chondrocyte-material interactions are important for the following cell behaviors. In this study, the surface of nanofibrous silk fibroin (NSF) meshes was modified by a microwave-induced argon plasma treatment in order to improve the cytocompatibility of the meshes used as cartilaginous grafts. In addition, the effects of a plasma treatment on the cellular behavior of chondrocytes on NSF were examined. The plasma treatment resulted in an increase in the hydrophilicity of NSF meshes suggesting that the cytocompatibility of the mesh might be improved. Furthermore, the human articular chondrocytes showed higher viability on the surface-modified NSF meshes. These results suggest that the surface modification of NSF meshes by plasma can enhance the cellular behavior of chondrocytes and may be used in tissue engineering.