• Journal of Life Science
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• v.21 no.12
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• pp.1784-1788
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• 2011

The typical miRNA and its nearby host gene are co-expressed by sharing the same promoter. We assumed that miR-7b and its host gene FICT might use an identical promoter for their brain specific gene expression. Sequence comparison of the genomic DNA of mouse miR-7b, human miR-7-3 and their host genes by using the bioinformatic tools revealed high sequence homology and several putative transcription factor-binding sites on the promoter region. In order to probe the hypothesis we used a luciferase vector system into which we cloned the 5' upstream conserved region of miR-7b and FICT. The putative promoter region showed decreased luciferase activity, suggesting that the 5' upstream of miR-7b and FICT contain a negative regulator for gene expression.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.416-418
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• 2009

The hepatoprotective effect of Cordyceps militaris culture broth was determined using HaM/ICR strain mice. Compared to control, the intra-peritoneal injection of benzo($\alpha$)pyrene (B($\alpha$)P) remarkably increased the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the serum and the level of lipid peroxide (LPO) in liver tissue, which mean the liver was damaged by B($\alpha$)P. However, compared to B($\alpha$)P, oral administration of C. militaris culture broth showed decrement of AST, ALT, and LPO activities and increment GST activity and GSH level in liver tissue. These suggest that C. militaris culture broth recovered hepatic damage induced by B($\alpha$)P.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.5
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• pp.269-274
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• 2002

A large number of factors such as osteotropic hormones, cytokines, or growth factors are related to the bone remodeling which is characterized by the coupling of osteoclast-mediated bone resorption and osteoblast-mediated bone formation. Recent investigations have indicated that cytokines such as $interleukin-1{\beta}\;(IL-1{\beta})$ and tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ play a potential role in the bone resorption associated with a variety of pathological conditions such as inflammatory osteolytic disease. Collagen is the most abundant protein of the extracellular matrix of bone, and the participation of collagenase in bone resorption has been widely investigated. In this study, effects of $IL-1{\beta}$ and $TNF-{\alpha}$ on the release of collagenase from osteoblastic cells were measured. The gelatinase activity was also measured by gel substrate analysis (zymography) after electrophoresis of conditioned media of osteoblastic cell culture. $IL-1{\beta}$ increased the collagenase activity in ROS17/2.8 and HOS cell culture. $TNF-{\alpha}$ also increased the collagenase activity of osteoblastic cells. When two kinds of cytokines were treated simultaneously in the culture of osteoblastic cells, synergistic increase of collagenase activity was seen in ROS17/2.8 cells. $IL-1{\beta}$ and $TNF-{\alpha}$ significantly increased the collagenase activity after 6 hour treatment in the osteoblastic cell culture, and there was no additional increase according to the culture period. Osteoblastic cells released the gelatinase and molecular weight of this enzyme was measured about 70 KDa as assessed by zymogram. $IL-1{\beta}$ and $TNF-{\alpha}$ showed increase of the gelatinase activity produced by ROS17/2.8 and HOS cells. Taken together, this study suggested that $IL-1{\beta}$ and $TNF-{\alpha}$ can modulate bone metabolism, at least in part, by increased release of collagenase and gelatinase from osteoblasts.

• Korean Journal of Microbiology
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• v.38 no.3
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• pp.198-204
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• 2002

Poliovirus is a member of enterovirus which causes paralytic poliomyelitis, encephalitis and aseptic meningitis. Since poliovirus is spread by the fecal-oral route and poliovirus-contaminated water could be a potential threat for public health, detection of poliovirus in drinking water resource is important. Infectious poliovirus and poliovirus inactivated by heat or UV were used to test three detection methods such as cell culture method, reverse transcription-polymerase chain reaction (RT-PCR) and integrated cell culture (ICC)-PCR. Infectious poliovirus was detected by all three methods and ICC-PCR was the most sensitive and fast in detecting poliovirus. Inactivated polioviruses could not be detected by cell culture or ICC-PCR methods. On the other hand, heat- inactivated viruses could be detected by RT-PCR. Thus it is suggested that ICC-PCR method is the most sensitive and effective in detecting infectious polioviruses in water sample.

• Journal of Periodontal and Implant Science
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• v.49 no.3
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• pp.193-204
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• 2019

Purpose: The reaction of cells to a titanium implant depends on the surface characteristics of the implant which are affected by decontamination. The aim of this study was to evaluate the cytocompatibility of titanium disks treated with various decontamination methods, using salivary bacterial contamination with dental pellicle formation as an in vitro model. Methods: Sand-blasted and acid-etched (SA) titanium disks were used. Three control groups (pristine SA disks [SA group]; salivary pellicle-coated SA disks [pellicle group]; and biofilm-coated, untreated SA disks [NT group]) were not subjected to any decontamination treatments. Decontamination of the biofilm-coated disks was performed by 14 methods, including ultrasonic instruments, rotating instruments, an air-powder abrasive system, a laser, and chemical agents. MG63 cells were cultured in the presence of the treated disks. Cell proliferation assays were performed on days 2 and 5 of cell culture, and cell morphology was analyzed by immunofluorescence and scanning electron microscopy (SEM). A vascular endothelial growth factor (VEGF) assay was performed on day 5 of culture. Results: The cell proliferation assay revealed that all decontaminated disks, except for the 2 groups treated using a plastic tip, showed significantly less cell proliferation than the SA group. The immunofluorescence and SEM analyses revealed that most groups showed comparable cell density, with the exception of the NT group, in which the cell density was lower and bacterial residue was observed. Furthermore, the cells grown with tetracycline-treated titanium disks showed significantly lower VEGF production than those in the SA group. Conclusions: None of the decontamination methods resulted in cytocompatibility similar to that of pristine SA titanium. However, many methods caused improvement in the biocompatibility of the titanium disks in comparison with the biofilm-coated, untreated titanium disks. This suggests that decontamination is indispensable for the treatment of peri-implantitis, even if the original biocompatibility cannot be restored.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.29-36
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• 2021

Among natural products, the shells of black walnut(Juglans nigra), which are not used commercially and mostly discarded, were examined to investigate the physiological activity and the efficacy for the cosmetic application. DPPH radical scavenging activity of hot water extract of black walnut shells was 76.06% at 300 ㎍/mL. ABTS radical scavenging activity of the extract was 61% at 1000 ㎍/mL, showing excellent antioxidant activity. When the black walnut shell extract was applied to HaCaT cells, a skin keratinocyte, the viability of the cells was 92.6% at 250 ㎍/mL, showing a remarkably low effect on cell viability. At the concentration of 500 ㎍/mL, 67.35% of nitric oxide(NO) production was inhibited. It also showed an inhibitory effect on Hyaluronidase 31 times higher than that of Vitamin C at 100 ㎍/mL concentration. In conclusion, the black walnut shell extract showed high potentials for the cosmeceutical applications, suggesting the possibility of using it as a high value-added natural material in various industries such as food, fragrance, healthcare, and pharmaceuticals.

• Journal of Periodontal and Implant Science
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• v.52 no.1
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• pp.77-87
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• 2022

Purpose: This pilot study assessed the immediate in vivo effect of high peak pulse power neodymium-doped yttrium aluminum garnet (Nd:YAG) laser monotherapy on selected red/orange complex periodontal pathogens in deep human periodontal pockets. Methods: Twelve adults with severe periodontitis were treated with the Laser-Assisted New Attachment Procedure (LANAP®) surgical protocol, wherein a free-running, digitally pulsed, Nd:YAG dental laser was used as the initial therapeutic step before mechanical root debridement. Using a flexible optical fiber in a handpiece, Nd:YAG laser energy, at a density of 196 J/cm² and a high peak pulse power of 1,333 W/pulse, was directed parallel to untreated tooth root surfaces in sequential coronal-apical passes to clinical periodontal probing depths, for a total applied energy dose of approximately 8-12 joules per millimeter of periodontal probing depth at each periodontal site. Subgingival biofilm specimens were collected from each patient before and immediately after Nd:YAG laser monotherapy from periodontal pockets exhibiting ≥6 mm probing depths and bleeding on probing. Selected red/orange complex periodontal pathogens (Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia/nigrescens, Fusobacterium nucleatum, Parvimonas micra, and Campylobacter species) were quantified in the subgingival samples using established anaerobic culture techniques. Results: All immediate post-treatment subgingival biofilm specimens continued to yield microbial growth after Nd:YAG laser monotherapy. The mean levels of total cultivable red/orange complex periodontal pathogens per patient significantly decreased from 12.0% pretreatment to 4.9% (a 59.2% decrease) immediately after Nd:YAG laser monotherapy, with 3 (25%) patients rendered culture-negative for all evaluated red/orange complex periodontal pathogens. Conclusions: High peak pulse power Nd:YAG laser monotherapy, used as the initial step in the LANAP® surgical protocol on mature subgingival biofilms, immediately induced significant reductions of nearly 60% in the mean total cultivable red/orange complex periodontal pathogen proportions per patient prior to mechanical root instrumentation and the rest of the LANAP® surgical protocol.

• The korean journal of orthodontics
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• v.53 no.1
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• pp.16-25
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• 2023

Objective: We aimed to evaluate the cell viability and antimicrobial effects of orthodontic bands coated with silver or zinc oxide nanoparticles (nano-Ag and nano-ZnO, respectively). Methods: In this experimental study, 30 orthodontic bands were divided into three groups (n = 10 each): control (uncoated band), Ag (silver-coated band), and ZnO (zinc oxide-coated band). The electrostatic spray-assisted vapor deposition method was used to coat orthodontic bands with nano-Ag or nano-ZnO. The biofilm inhibition test was used to assess the antimicrobial effectiveness of nano-Ag and nano-ZnO against Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. Biocompatibility tests were conducted using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The groups were compared using oneway analysis of variance with a post-hoc test. Results: The Ag group showed a significantly higher reduction in the number of L. acidophilus, C. albicans, and S. mutans colonies than the ZnO group (p = 0.015, 0.003, and 0.005, respectively). Compared with the control group, the Ag group showed a 2-log₁₀ reduction in all the microorganisms' replication ability, but only S. mutants showed a 2-log₁₀ reduction in replication ability in the ZnO group. The lowest mean cell viability was observed in the Ag group, but the difference between the groups was insignificant (p > 0.05). Conclusions: Coating orthodontic bands with nano-ZnO or nano-Ag induced antimicrobial effects against oral pathogens. Among the nanoparticles, nano-Ag showed the best antimicrobial activity and nano-ZnO showed the highest biocompatibility.

• Restorative Dentistry and Endodontics
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• v.49 no.1
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• pp.4.1-4.9
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• 2024

Objectives: This study aims to correlate caries-causing microorganism load, lactic acid estimation, and blood groups to high caries risk in diabetic and non-diabetic individuals and low caries risk in healthy individuals. Materials and Methods: This study includes 30 participants divided into 3 groups: Group A, High-risk caries diabetic individuals; Group B, High-risk caries non-diabetic individuals; and Group C, Low-risk caries individuals. The medical condition, oral hygiene, and caries risk assessment (American Dental Association classification and International Caries Detection and Assessment System scoring) were documented. Each individual's 3 mL of saliva was analyzed for microbial load and lactic acid as follows: Part I: 2 mL for microbial quantity estimation using nutrient agar and blood agar medium, biochemical investigation, and carbohydrate fermentation tests; Part II: 0.5 mL for lactic acid estimation using spectrophotometric analysis. Among the selected individuals, blood group correlation was assessed. The χ² test, Kruskal-Wallis test, and post hoc analysis were done using Dunn's test (p < 0.05). Results: Group A had the highest microbial load and lactic acid concentration, followed by Groups B and C. The predominant bacteria were Lactobacilli (63.00 ± 15.49) and Streptococcus mutans (76.00 ± 13.90) in saliva. Blood Group B is prevalent in diabetic and non-diabetic high-risk caries patients but statistically insignificant. Conclusions: Diabetic individuals are more susceptible to dental caries due to high microbial loads and increased lactic acid production. These factors also lower the executing tendency of neutrophils, which accelerates microbial accumulation and increases the risk of caries in diabetic individuals.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.261-267
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• 2016

The present study examined the effect of the dietary administration of a halophilic bacterium Bacillus sp. Mk22 on the growth improvement of black tiger shrimp, Penaeus monodon, and reduced shrimp infection by Vibrio parahaemolyticus and white spot syndrome virus (WSSV). The shrimp were fed 45 days using three experimental diets: no addition (control), commercial probiotic, and Bacillus sp. Mk22. The shrimp treated with the halophilic bacterium Mk22 showed a significant improvement of growth (7.1 ± 0.21 g), survival (94.3 ± 0.58%), weight gain (178 ± 4.93 g), and reduced feed conversion rate (0.8 ± 0.03 g) compared with the shrimp in the other groups. The shrimp treated with Bacillus sp. Mk22 also showed a lower Vibrio count (0.02 ± 0.01 × 10² CFU/ml) in the shrimp culture water compared with the other groups. The shrimp in the three groups were challenged with either Vibrio or WSSV. For the Vibrio infection, no mortality was observed from water infection or oral feeding infection in the commercial probiotic group and Mk 22 group. For the WSSV infection, a 68% survival rate from water infection and 20% survival rate from oral feeding infection was observed on day 45 in the Mk22 group, while 100% mortalities were recorded at a much earlier time in both the control and commercial probiotic groups. The antioxidant enzyme activities, indicators of oxidative stress, such as catalase and superoxide dismutase, significantly decreased in both the Vibrio and WSSV-infected Mk22 groups compared with the other groups, indicating that Bacillus sp. Mk22 was effective in reducing oxidative stress, possibly due to the reduced infection.