• Restorative Dentistry and Endodontics
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• v.39 no.2
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• pp.79-88
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• 2014

Appropriate use of local hemostatic agent is one of the important factors on the prognosis of endodontic microsurgery. However, most investigations to date focus on the hemostatic efficacy of the agents, whereas their biologic characteristics have not received enough attention. The purpose of this paper was to review the biologic response of local hemostatic agents, and to provide clinical guidelines on their use during endodontic microsurgery. Electronic database (PUBMED) was screened to search related studies from 1980 to 2013, and 8 clinical studies and 18 animal studies were identified. Among the materials used in these studies, most widely-investigated and used materials, epinephrine, ferric sulfate (FS) and calcium sulfate (CS), were thoroughly discussed. Influence of these materials on local tissue and systemic condition, such as inflammatory and foreign body reaction, local ischemia, dyspigmentation, delayed or enhanced bone and soft tissue healing, and potential cardiovascular complications were assessed. Additionally, biological property of their carrier materials, cotton pellet and absorbable collagen, were also discussed. Clinicians should be aware of the biologic properties of local hemostatic agents and their carrier materials, and should pay attention to the potential complications when using them in endodontic microsurgery.

• Korean Journal of Head & Neck Oncology
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• v.34 no.2
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• pp.1-9
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• 2018

With the emerging knowledge about tumor biology specific for human papillomavirus (HPV)-related head and neck cancers, the classical understanding about the curative surgery in head and neck cancers are starting to progress, customized for their HPV-associations and ultimately specific for tumor biologic characteristics. The common rule for surgery should reflect the biologic characteristics of target tumors, but still, multi-institutional large-scale data could be scarce, due to the subjective feature of surgical treatment itself. However, the impact of HPV for margin determination is now being questioned by multiple groups, and typical example is European Cooperative Oncology Group (ECOG)-3311 study. Here, we review the impact of viral association for surgical decision and its biological background and implications.

• The korean journal of orthodontics
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• v.43 no.3
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• pp.120-126
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• 2013

Objective: To gain basic information regarding the biologic stability of plasma ion-implanted miniscrews and their potential clinical applications. Methods: Sixteen plasma ion-implanted and 16 sandblasted and acid-etched (SLA) miniscrews were bilaterally inserted in the mandibles of 4 beagles (2 miniscrews of each type per quadrant). Then, 250 - 300 gm of force from Ni-Ti coil springs was applied for 2 different periods: 12 weeks on one side and 3 weeks contralaterally. Thereafter, the animals were sacrificed and mandibular specimens including the miniscrews were collected. The insertion torque and mobility were compared between the groups. The bone-implant contact and bone volume ratio were calculated within 800 mm of the miniscrews and compared between the loading periods. The number of osteoblasts was also quantified. The measurements were expressed as percentages and analyzed by independent t-tests (p < 0.05). Results: No significant differences in any of the analyzed parameters were noted between the groups. Conclusions: The preliminary findings indicate that plasma ion-implanted miniscrews have similar biologic characteristics to SLA miniscrews in terms of insertion torque, mobility, bone-implant contact rate, and bone volume rate.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.6
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• pp.751-763
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• 2005

Statement of problem. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. The surface quality of the implant depends on the chemical, physical, mechanical and topographical properties of the surface. The different properties will interact with each other and a change in thickness of the oxide layer may also result in a change in surface energy, the surface topography and surface, chemical composition. However, there is limited the comprehensive study with regard to changed surface and biologic behavior of osteoblast by anodization. Purpose of study. The aim of this study was to analyze the characteristics of an oxide layer formed and to evaluate the cellular biologic behaviors on titanium by anodic oxidation (anodization) by cellular proliferation, differentiation, ECM formation and gene expression. And the phospholipase activity was measured on the anodized surface as preliminary study to understand how surface properties of Ti implant are transduced into downstream cellular events. Methods and Materials. The surface of a commercially pure titanium(Grade 2) was modified by anodic oxidation. The group 1 samples had a machined surface and other three experimental specimens were anodized under a constant voltage of 270 V(Group 2), 350 V(Group 3), and 450 V(Group 4). The specimen characteristics were inspected using the following five categories; the surface morphology, the surface roughness, the thickness of oxide layer, the crystallinity, and the chemical composition of the oxide layer. Cell numbers were taken as a marker for cell proliferation. While the expression of alkaline phosphatase and Runx2 (Cbfa1) was used as early differentiation marker for osteoblast. The type I collagen production was determined, which constitutes the main structural protein of the extracellular matrix. Phospholipase $A_2$ and D activity were detected. Results. (1) The anodized titanium had a porous oxide layer, and there was increase in both the size and number of pores with increasing anodizing voltage. (2) With increasing voltage, the surface roughness and thickness of the oxide film increased significantly (p<0.01), the $TiO_2$phase changed from anatase to rutile. During the anodic oxidization, Ca and P ions were more incorporated into the oxide layer. (3) The in vitro cell responses of the specimen were also dependant on the oxidation conditions. With increasing voltage, the ALP activity, type I collagen production, and Cbfa 1 gene expression increased significantly (p<0.01), while the cell proliferation decreased. (4) In preliminary study on the relation of surface property and phospholipase, PLD activity was increased but $PLA_2$ activity did not changed according to applied voltage. Conclusion. The anodized titanium shows improved surface characteristics than the machined titanium. The surface properties acquired by anodization appear to give rise more mature osteoblast characteristics and might result in increased bone growth, and contribute to the achievement of a tight fixation. The precise mechanism of surface property signaling is not known, may be related to phospholipase D.

• Korean Journal of Clinical Pharmacy
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• v.29 no.2
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• pp.109-114
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• 2019

Background: Rheumatoid arthritis (RA) is a systemic inflammatory disease that manifests as joint damage or athletic disability via sustained inflammation of the synovial membrane. The risk of cardiovascular disease (CVD) is higher in RA patients. This study aimed at evaluating the association between CVD comorbidities and RA by comparing a pharmacotherapy group with a non-pharmacotherapy group. Methods: Patient sample data from the Health Insurance Review and Assessment Service (HIRA-NPS-2016) were used. Inverse probability of treatment weighting (IPTW) using the propensity score was used to minimize the differences in patient characteristics. Logistic regression analysis was used to evaluate the risk of CVD comorbidities. Results: The analyses included 1,207,213 patients, of which 33,122 (2.8%) had RA. The odds ratios (OR) of CVD comorbidities were increased in RA patients; ischemic heart disease (IHD: OR 1.75; 95% CI 1.73, 1.77), cerebral infarction (CERI: OR 1.28; 95% CI 1.26, 1.30), hypertension (HTN: OR 1.44; 95% CI 1.43, 1.45), diabetes mellitus (DM: OR 2.04; 95% CI 2.03, 2.06), and dyslipidemia (DL: OR 3.49; 95% CI 3.47, 3.51). The ORs of IHD, CERI, HTN, and DM in the traditional DMARD and biologic treatment groups were decreased, compared with those in the non-pharmacotherapy group. Conclusions: Thus, CVD risk was higher in RA patients, considering age, sex, and socioeconomic status. Appropriate pharmacotherapy could decrease the risk of CVD comorbidities in RA patients.

• Fibers and Polymers
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• v.2 no.2
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• pp.71-74
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• 2001

Surface characterization of materials has been considered critical in the development of biomaterials, as many unfavorable responses from the body occur at the interface between a material and the body component. The contact angle measurement is one means to characterize the surface properties and to correlate them to the biocompatibility of materials. In this paper, surface characteristics of silk fibroin/S-carboxymethyl kerateine, representative fibrous proteins, were investigated by contact angle measurements of ESCA. The biocompatibility of the blends was evaluated based on minimal interfacial free energy concept, and compared with other potential biomaterials. It was also hypothesized that the enhanced surface polarity of the blends was generated from the conformational transition of proteins. This approach to evaluate the biocompatibility of materials based on surface characteristics may find wide utility in many biomedical applications.

• Journal of Korean Neurosurgical Society
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• v.47 no.1
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• pp.26-29
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• 2010

Objective: Recurrent lumbar disc herniation has been reported to occur in 5% to 15% of surgically treated primary lumbar disc herniation cases. We investigated the molecular biologic characteristics of primary herniated discs and recurrent discs to see whether the recurrent discs has the similar biological features with primary herniated discs. Methods: Primary hemiated disc and recurrent disc cells were obtained by discectomy of lumbar disc patients and cells were isolated and then taken through monolayer cultures. We compared chondrogenic and osteogenic mRNA gene expression, and western blot between the two groups. Results: The mRNA gene expression of recurrent disc cells were increased 1.47* times for aggrecan, 1.38 times for type I collagen, 2.04 times for type II collagen, 1.22 times for both Sox-9 and osteocalcin, and 1.31 times for alkaline phosphatase, respectively, compared with the primary herniated lumbar disc cells (*indicates p < 0.05). Westem blot results for each aggrecan, type I collagen, type II collagen, Sox-9, osteocalcin, and alkaline phosphatase were similar between the primary herniated disc cells and recurrent disc cells. Conclusion: These results indicate that the recurrent disc cells have similar chondrogenic and osteogenic gene expression compared to primary herniated disc cells. Therefore, we assumed that the regeneration of remaining discs could fill the previous discectomy space and also it could be one of the factors for disc recurrence especially in the molecular biologic field.

• Journal of Oral Medicine and Pain
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• v.32 no.3
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• pp.273-281
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• 2007

Zinc compounds have been used in various fields - cosmetics, medicine, and dentistry -because of its effective functions to human tissues or organs. Especially, it is well known that zinc has many biologic effects in oral cavity. Zinc ion can affect various oral microorganisms, resulting in reduction of oral bacteria, dental plaque, and dental caries. Also, zinc ion has an ability to reduce amounts of oral anaerobic bacteria and oral VSC and can reduce oral malodor. The author summarized the characteristics and toxicity of zinc, several forms of zinc compounds applied in human tissues, and reviewed biologic effects of Zinc in oral cavity (anti-bacterial effects, anti-plaque effects, anti-caries effects, and anti-VSC effects of zinc). Because of many advantages of zinc in oral cavity, it can be concluded that application of zinc compound to various oral diseases will be extended and activated, and promising.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1993.05a
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• pp.85-85
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• 1993

The clinical staging system for laryngeal cancers is not sufficient for prognosticator due to different biologic characteristics and their microenvironment according to primary sites. For determining the prognosticators, the authors peformed immunohistochemical staining to EGFR, p53 protein, and pRB in 40 cases of surgically treated squamous cell carcinomas of larynx in our institute during the past 5 years. The results are as followings; 1. The positive expression rate of p53 protein and negative expression rate of pRB showed correlations with clinical parameters. 2. The three-year survival rate for p53 protein positive cases was worse than the p53 protein negative cases. 3. Expression rate of EGFR was not correlated with the clinical parameters. As a conclusion, expression rates of p53 protein and pRB not only reflect well the biologic behavior of laryngeal cancer, but correlate closely with the tumor factors. Therefore they may be useful as the prognosticator to predict the malignant potency of laryngeal squamous cell carcinomas.

• Journal of Yeungnam Medical Science
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• v.34 no.1
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• pp.1-10
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• 2017

The life history of man is summarized as a birth-aging-disease-death. Man eventually ages and dies. How long can humans live? What is aging? Why do we age? Is aging inevitable? Can we rejuvenate? Recent researches on biological aging suggest that humans might overcome aging and rejuvenate. In this paper, we review the biologic characteristics of aging and the latest results of biological aging research, implicating that aging can be controlled, further treated, and that humans can ultimately be rejuvenated.