• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.4
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• pp.365-370
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• 2006

Viral, bacterial and fungal infections can be transmitted via allografts such as bone, skin, cornea and cardiovascular tissues. Allogenic bone grafts have possibility of transmission of hepatitis C, human immunodeficiency virus (HIV-1), human T-Cell leukaemia virus (HTLV), tuberculosis and other bacterias. The tissue bank should have a policy for obtaining information from the patient's medical report as to whether the donor had risk factors for infectious diseases. Over the past several years, improvements in donor screening criteria, such as excluding potential donor with "high risk" for HIV-1 and hepatitis infection, and donor blood testing result in the reduction of transmission of these diseases. During tissue processing, many allografts are exposed to antibiotics, disinfectants and terminal sterilization such as irradiation, which further reduce or remove the risk of transmitting diseases. Because the effectiveness of some tissue grafts such as, fresh frozen osteochondral grafts, depends on cellular viability, not all can be subjected to sterilization and processing steps and, therefore, the risk of transmission of infectious disease remains. This article is review of the transmission of considering infectious disease in allogenic bone transplantation and the processing steps of reducing the risk. The risk of viral transmission in allografts can be reduced in several standards. The most important are donor-screening tests and the removal of blood and soft tissues by processing steps under the aseptic environment. In conclusion, final sterilizations including the irradiation, can be establish the safety of allografts.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.323-336
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• 1996

This is a retrospective study on the patients with infection of the oral and maxillofacial region with the purpose of obtaining some useful data for diagnosis and treatment plan of that relatively common disease in dentistry. The used materials of study were 87 in total, including 52 male patients, 35 female patients who diagnosed and treated at the Department of the Dentistry in Hanyang Medical College Hospital for the period of Jan. 1990 to Dec. 1994. The author analyzed the distribution and incidence of sex, age, admission period, etiologic factors, etiologic teeth, treatment method of infections, pus culture, antibiotics sensibilities and medication. The result obtained as follows : 1. The developmental incidences by sex was superior in male by the ratio of 1.5 : 1 and the infection was most frequently occurred during the third decades(35.6%). 2. The number of admitted patients elevated in February, March, and April, and average of admission period was 9.8 days. 3. Main etiologic teeth showed on lower molar region in adult(63%) and upper molar region in primary dentition(46.1%). 4. Medications were administrated in all of the cases, and surgical incision and drainage were performed in 53% and extraction of the causative teeth were performed in 63.6% of all cases. 5. The most common involved fascial spaces were Buccal space(41.4%), Infraorbital space(27.6%), Submandibular space(16.1%),in order, and 9 cases(10.3%) were Ludwig's Angina. In 68.2% of the patients, and infection involved only one fascial space and in 21.8% of the patients, it involved to more fascial spaces. 6. The most causative organisms isolated from pus culture were Gram-positive facultative cocci(55.5%), and antibiotics sensitivities on the total isolated bacterial strains were exposed chloramphenicol(88.6%), Cephalothin(88.6%), Erythromycin(81.5%), Lincomycin(77.8%) in order, but it showed resistant on Gentamycin(58.3%), Tetracycline(56.5%), Methicillin(38.5%).

• Journal of Periodontal and Implant Science
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• v.39 no.sup2
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• pp.231-237
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• 2009

Purpose: Cytolethal distending toxin (CDT) is a family of heat-labile cytotoxins produced by several gram-negative mucosa-associated pathogens, including Aggregatibacter actinomycetemcomitans. CDT is well known to be capable of inducing growth arrest, morphological alterations, and eventually death in various cells. CDT belongs to a tripartite $AB_2$ toxin (CdtB: the enzymatic A subunit; CdtA and CdtC: the heterodimeric B subunit). Previous studies proposed that CdtA and CdtC together bind to a cell surface receptor and glycolipids act as a receptor for A. actinomycetemcomitans CDT (AaCDT). In this study, recombinant CdtA and CdtC proteins of AaCDT were co-expressed in a bacterial expression system and tested for their affinity for $GM_1$ ganglioside. Methods: The genes for CdtA and CdtC from A. actinomycetemcomitans Y4 were utilized to construct the expression vectors, pRSET-cdtA and pET28a-cdtC. Both CdtA and CdtC proteins were expressed in Escherichia coli BL21(DE3) and then purified using hexahistidine (His6) tag. The identity of purified protein was confirmed by anti-His6 antibody and monoclonal anti-CdtA antibody. Furthermore, the affinity of recombinant protein to $GM_1$ ganglioside was checked through ELISA. Results: Recombinant CdtA and CdtC proteins were expressed as soluble proteins and reacted to anti-His6 and monoclonal anti-CdtA antibodies. ELISA revealed that purified soluble CdtA-CdtC protein bound to $GM_1$ ganglioside, while CdtA alone did not. Conclusions: Co-expression of CdtA and CdtC proteins enhanced the solubility of the proteins in E. coli, leading to convenient preparation of active CdtA-CdtC, a critical material for the study of AaCDT pathogenesis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.1
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• pp.28-35
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• 2008

Purpose: The nitric oxide (NO) release by inducible nitric oxide synthase (iNOS) is the key events in macrophage response to lipopolysaccharide (LPS) which is suggested to be a crucial mediator for inflammatory and innate immune responses. NO is an important mediator involved in many host defense action and may also lead to a harmful host response to bacterial infection. However, given the importance of iNOS in a variety of pathophysiological conditions, control of its expression and signaling events in response to LPS has been the subject of considerable investigation. Materials and Methods: The Raw264.7 macrophage cell line was used to observe LPS-stimulated iNOS expression. The expression of iNOS is observed by Western blot analysis and real-time RT-PCR. Protein kinase C $(PKC)-{\alpha}$ overexpressing Raw264.7 cells are established to determine the involvement of $PKC-{\alpha}$ in LPS-mediated iNOS expression. $NF-{\kappa}B$ activity is measured by $I{\kappa}B{\alpha}$ degradation and $NF-{\kappa}B$ luciferase activity assay. Results: We found that various PKC isozymes regulate LPS-induced iNOS expression at the transcriptional and translational levels. The involvement of $PKC-{\alpha}$ in LPS-mediated iNOS induction was further confirmed by increased iNOS expression in $PKC-{\alpha}$ overexpressing cells. $NF-{\kappa}B$ dependent transactivation by LPS was observed and $PKC-{\alpha}$ specific inhibitory peptide abolished this activation, indicating that $NF-{\kappa}B$ activation is dependent on $PKC-{\alpha}$. Conclusion: Our data suggests that $PKC-{\alpha}$ is involved in LPS-mediated iNOS expression and that its downstream target is $NF-{\kappa}B$. Although $PKC-{\alpha}$ is a crucial mediator in the iNOS regulation, other PKC isozymes may contribute LPS-stimulated iNOS expression. This finding is needed to be elucidated in further study.

• Journal of Pharmacopuncture
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• v.19 no.3
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• pp.213-224
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• 2016

Objectives: Ginseng Rh2+ is enzyme-treated ginseng extract containing high amounts of converted ginsenosides, such as compound k, Rh2, Rg3, which have potent anticancer activity. We conducted general and genetic toxicity tests to evaluate the safety of ginseng Rh2+. Methods: An acute oral toxicity test was performed at a high-level dose of 4,000 mg/kg/day in Sprague-Dawley (SD) rats. A 14-day range-finding study was also conducted to set dose levels for the 90-day study. A subchronic 90-day toxicity study was performed at dose levels of 1,000 and 2,000 mg/kg/day to investigate the no-observed-adverse-effect level (NOAEL) of ginseng Rh2+ and target organs. To identify the mutagenic potential of ginseng Rh2+, we conducted a bacterial reverse mutation test (Ames test) using amino-acid-requiring strains of Salmonella typhimurium and Escherichia coli (E. coli), a chromosome aberration test with Chinese hamster lung (CHL) cells, and an in vivo micronucleus test using ICR mice bone marrow as recommended by the Korean Ministry of Food and Drug Safety. Results: According to the results of the acute oral toxicity study, the approximate lethal dose (ALD) of ginseng Rh2+ was estimated to be higher than 4,000 mg/kg. For the 90-day study, no toxicological effect of ginseng Rh2+ was observed in body-weight changes, food consumption, clinical signs, organ weights, histopathology, ophthalmology, and clinical pathology. The NOAEL of ginseng Rh2+ was established to be 2,000 mg/kg/day, and no target organ was found in this test. In addition, no evidence of mutagenicity was found either on the in vitro genotoxicity tests, including the Ames test and the chromosome aberration test, or on the in vivo in mice bone marrow micronucleus test. Conclusion: On the basis of our findings, ginseng Rh2+ is a non-toxic material with no genotoxicity. We expect that ginseng Rh2+ may be used as a novel adjuvant anticancer agent that is safe for long-term administration.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.312-317
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• 2002

Indigenous lactobacilli were isolated from vaginas of Korean women for possible use in ecological treatment of bacterial vaginosis. Vaginal swab samples were obtained from a gynecological clinic and streaked on Rogosa SL agar plates to select the most predominant lactobacilli in each sample. The preliminary identification of the isolates as lactobacilli was based on microscopic observation of Gram-positive rod-shaped cell morphology. The initial characterization was performed on 108 isolates in terms of their cell surface hydrophobicity (CSH), antimicrobial activity, and hydrogen peroxide (H₂O₂) production capability, and 10 isolates were then selected for further molecular identification. For a rapid procedure to identify lactobacilli, polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses of the l6S rRNA genes were applied. The 10 selected lactobacilli and 9 different reference strains of Lactobacillus spp. were characterized by PCR-RFLP where the amplified l6S rDNA was digested with 7 different restriction endonucleases prior to analysis. DNA sequencing of the 16S rRNA gene of one particular isolate, KLB 46, that had been identified as L. crispatus by the PCR-RFLP analysis, further confirmed its identity as L. crispatus.

• Korean Journal of Microbiology
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• v.55 no.1
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• pp.58-60
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• 2019

Anaerobic Gram-negative bacterium Prevotella intermedia is a part of normal flora of the oral cavity and associated with various types of oral and systemic diseases. We present here a draft genome sequence of P. intermedia ATCC 15032, originally isolated from cervicofacial actinomycosis. The genome is 2,848,426 bp in length and has a GC content of 43.45%. The genome includes 2,358 protein-coding genes, 5 rRNAs, and 43 tRNA. The sequence information will provide important clues in understanding the genome diversity within the bacterial species, and genetic basis for phenotypic differences among P. intermedia strains.

• Korean Journal of Organic Agriculture
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• v.30 no.1
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• pp.103-118
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• 2022

Photorhabdus is a bacterial symbiont of entomopathogenic nematodes of the genus Heterorhabditis in the family Heterorhabditidae. Photorhabdus is known to have nematicidal activity in addition to insecticidal activity. P. temperata isolated from Korean indigenous H. megidis Gwangju strain also produced high control efficacy against root-knot nematode Meloidogyne incognita and root-lesion nematode Pratylenchus penetrans. P. temperata has drawn interest as a potential bionematicide for the control of root-knot nematodes thereby. For the registration as an organic agricultural material, the toxicity of P. temperata was assessed by the acute toxicity test in carp (Cyprinus carpio) and acute oral and dermal toxicity tests in Sprague-Dawley rat (Rattus norvegicus) in compliance with the guidelines of the Rural Development Administration (RDA). In the acute toxicity test in fish, neither lethality nor abnormal responses of carp were observed. Body length and weight of carp and changes in DO concentrations and pH values were not significantly different between the treated group and the untreated control. In the acute oral and dermal toxicity tests, clinical signs, abnormal behavior, mortality, and pathological findings were not observed in all the experimental rats. The weight increment of all rats was normal. Acute toxicity results of P. temperata in fish and rats belonged to categories III, IV, and IV of RDA, respectively. Toxicity results of the present study indicated that P. temperata could be a safe and promising bionematicide against root-knot nematodes and root lesion nematode.

• The korean journal of orthodontics
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• v.53 no.2
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• pp.125-136
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• 2023

Before progress was recently made in the application of temporary anchorage devices (TADs) in bio-mechanical design, orthodontists were rarely able to intrude molars to reduce upper posterior dental height (UPDH). However, TADs are now widely used to intrude molars to flatten the occlusal plane or induce counterclockwise rotation of the mandible. Previous studies involving clinical or animal histological evaluation on changes in periodontal conditions after molar intrusion have been reported, however, studies involving human histology are scarce. This case was a Class I malocclusion with a high mandibular plane angle. Upper molar intrusion with TADs was performed to reduce UPDH, which led to counterclockwise rotation of the mandible. After 5 months of upper molar intrusion, shortened clinical crowns were noticed, which caused difficulties in oral hygiene and hindered orthodontic tooth movement. The mid-treatment cone-beam computed tomography revealed redundant bone physically interfering with buccal attachment and osseous resective surgeries were followed. During the surgeries, bilateral mini screws were removed and bulging alveolar bone and gingiva were harvested for biopsy. Histological examination revealed bacterial colonies at the bottom of the sulcus. Infiltration of chronic inflammatory cells underneath the non-keratinized sulcular epithelium was noted, with abundant capillaries being filled with red blood cells. Proximal alveolar bone facing the bottom of the gingival sulcus exhibited active bone remodeling and woven bone formation with plump osteocytes in the lacunae. On the other hand, buccal alveolar bone exhibited lamination, indicating slow bone turnover in the lateral region.

• Journal of Korean Academy of Dental Administration
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• v.6 no.1
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• pp.11-18
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• 2018

The aim of this study was to evaluate the competency of the Easyperio test, a genetic test method based on real time PCR for the detection of bacteria that cause dental caries and periodontal disease. To verify the validity of this text, various dental health evaluations were administered to 33 boys between the ages of 12 to 14, as this age group commonly experiences dental caries. These evaluations included a dental caries experience survey, a first molar health evaluation, the Dentocult Streptococcus mutans (SM) strip mutans, the Dentocult Lactobacillus spp (LB) test, and the Easyperio test. The correlation coefficients between the level of the Dentocult SM strip mutans and the dental caries experience were DT (R=0.570, p=0.001), DMFT (R=0.376, p=0.031), and first molar health (R=-0.395, p=0.023). The correlation coefficients between the amount of SM in the Easyperio test and dental caries experience were DT (R=0.528, p=0.002), DMFT (R=0.369, p=0.035), and first molar health (R=-0.426, p=0.013). The correlation coefficients between the level of the dentocult SM strip mutans and the SM amounts of the Easyperio test were S.mi (R=0.564 p=0.001) and S.mu (R=0.621, p=0.002). The correlation coefficients between the level of the Dentocult LB test and the SM amount of Easyperio test was S.mi (R=0.495, p=0.003). In conclusion, Easyperio test may be an easy and effective method for the differentiation and diagnosis of dental caries through quantitative and qualitative analysis of oral bacteria.