Biomedical subjects

Ju-Hee Song

Publications and source records attributed to Ju-Hee Song.

8 recordsLinked to original sources

PubMed2006

In vitro inhibitory effects of Polygonum cuspidatum on bacterial viability and virulence factors of Streptococcus mutans and Streptococcus sobrinus.

OBJECTIVES: Polygonum cuspidatum has been used in Korean folk medicine to improve oral hygiene. This study was performed to evaluate the effects of methanol extract from root of P. cuspidatum (MEP) on bacterial viability and the virulence factors of Streptococcus mutans and Streptococcus sobrinus. METHODS: To test the effects of MEP on bacterial viability, we determined the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) against 20 bacterial strains, including S. mutans and S. sobrinus, using a micro-dilution assay. In case of S. mutans and S. sobrinus, the assays for time-kill and bacterial growth rate at sub-MIC concentrations were also performed. To determine effects of the extract on the virulence factors of S. mutans and S. sobrinus, the assays for sucrose-dependent adherence, water-insoluble glucan formation, glycolytic acid production, and acid tolerance were performed at sub-MIC levels. Phytochemical analysis for constituents of MEP was carried out. RESULTS: MEP showed a broad antibacterial range (MIC 0.5-4 mg/ml). The MBC was two to four times higher than the MIC. The time-kill curves showed S. mutans and S. sobrinus were significantly killed after 1h of incubation. At sub-MIC levels, doubling times of S. mutans and S. sobrinus dose-dependently increased up to 211% and 123%, respectively. At sub-MIC levels, MEP also showed inhibitory effects on the virulence factors of S. mutans and S. sobrinus in a dose-dependent fashion. Phytochemical analysis revealed the presence of alkaloids, sterol/terpenes, tannins, flavonoids, and carbohydrates. CONCLUSION: These data indicate that MEP has inhibitory effects on bacterial viability at higher concentrations (> or =MIC) and the virulence factors of S. mutans and S. sobrinus at sub-MIC concentrations, suggesting that it might be useful for the control of dental plaque formation and subsequent dental caries formation.

Anti-Bacterial Agents↗

PubMed2006

In vitro anti-cariogenic activity of dichloromethane fraction from Rheum undulatum L. root.

This study aimed to evaluate in vitro effects of Rheum undulatum L. root on the development of dental caries, especially its effects on viability, dental plaque formation, and glycolytic acid production of Streptococcus mutans and Streptococcus sobrinus. Methanol extract of Rheum undulatum L. root and its fractions were prepared and tested. Among the test extract and fractions, dichloromethane fraction (DF) showed the most active antibacterial activity (inhibition zone: 13-17 mm) against S. mutans and S. sobrinus in a disc diffusion method. Minimal inhibitory concentrations (MICs) of DF against these bacteria ranged from 0.25 to 0.5 mg/mL. Furthermore, DF significantly inhibited the caries-inducing factors of these bacteria. At sub-MIC levels, DF inhibited in vitro dental plaque formation by S. mutans and S. sobrinus (IC50= 0.079 and 0.142 mg/mL, respectively), which was caused, in part, by the inhibitory effect on the activity of glucosyltransferases. A significant reduction of glycolytic acid production was found at the concentration as low as 0.032 mg/mL for S. mutans and 0.063 mg/mL for S. sobrinus. The possible bioactive compounds that are inducing in vitro anti-cariogenic activity of DF are unknown. Based on the preliminary phytochemical analysis, the activity of DF may be related to the presence of anthraquinones, cardiac glycosides, coumarines, sterols/terpenes, and phenolics. These results indicate that DF is probably useful for the control of dental plaque formation and subsequent dental caries development.

Anti-Bacterial Agents↗

PubMed2004

The polymorphisms of Tim-1 promoter region are associated with rheumatoid arthritis in a Korean population.

It has been determined that the family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is expressed on T cells. A member of the TIM family, TIM-1, is considered to be a membrane protein associated with the development of Th2-biased immune responses and selectively expressed on Th2 cells. We previously showed that the exon 4 variations of Tim-1 are associated with susceptibility to allergic diseases, as well as autoimmune diseases such as rheumatoid arthritis (RA). In this study, we assessed the association between genotype and allele frequencies of the Tim-1 gene promoter region, in both RA patients and the controls without RA, using polymerase chain reaction-restriction fragment length polymorphism and single-base extension methods. We further investigated the relationships among the genotypes of each polymorphism and C-reactive protein or rheumatoid factor levels in RA patients. The genotype and allele frequencies of the -1637A>G polymorphism in RA patients are significantly different from those in the non-RA controls (P=0.0004 and P=0.001, respectively). Our results strongly suggest that polymorphism in the Tim-1 promoter region might be associated with susceptibility to RA.

Adult↗

PubMed2004

Analysis of the polymorphisms in eotaxin gene family and their association with asthma, IgE, and eosinophil.

The eotaxin gene family (eotaxin, eotaxin-2, and eotaxin-3) has been implicated in the recruitment of eosinophils, basophiles, and Th2 lymphocytes that is a central aspect of allergic diseases such as asthma. To determine whether the single nucleotide polymorphisms (SNPs) of eotaxin gene family are associated with susceptibility to asthma, we scanned 225 asthma patients and 294 non-asthmatic controls using the direct sequencing method. We further investigated the relationships among each SNP, eosinophils, and serum total IgE levels in asthma patients. Eleven SNPs were identified in the eotaxin gene family. We found that EoB179T > C (P = 0.0001), EoB275C > T (P = 0.018) of the eotaxin-2 and EoA2497T > G (P = 0.003) of the eotaxin-3 were significantly associated with the susceptibility of asthma. Furthermore, our data demonstrated for the first time that EoA2497T > G (P = 0.005) is related to serum total IgE level while EoA77C > T (P = 0.035) and EoA2497T > G (P = 0.033) are related to the peripheral blood eosinophil counts in asthma. Our results suggest that the polymorphisms of the eotaxin gene family are associated with the susceptibility of asthma and Eotaxin-3 might play the critical role for the recruitment of eosinophils and the maintenance of IgE levels.

Adult↗

PubMed2004

Molecular variations in Th1-specific cell surface gene Tim-3.

The family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is identified to be expressed on T cells. A member of Tim family, Tim-3 (T cell immunoglobulin mucin 3) is selectively expressed on the surface of differentiated Th1 cells. Tim-3 might have an important role in the induction of autoimmune diseases by regulating macrophage activation and interacts with Tim-3 ligand to regulate Th1 responses. To determine the variation sites in the coding and promoter region of human Tim-3 gene, we performed variation scanning by direct sequencing using the genomic DNA isolated from the patients with asthma or allergic rhinitis and healthy controls without asthma and allergic rhinitis. We identified four single nucleotide polymorphisms (SNPs) including one novel SNPs (-1541C>T) and two variation sites (-1292_-1289delTAAA and -1282_-1278dupTAAAA) in the coding and promoter region of human Tim-3 gene in both the patients and healthy groups.

Asthma↗

PubMed2004

The exon 4 variations of Tim-1 gene are associated with rheumatoid arthritis in a Korean population.

The family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is identified to be expressed on T cells. A member of Tim family, TIM-1, is considered as a membrane protein that is associated with the development of Th2 biased immune responses and selectively expressed on Th2 cells. In the present study, we analyzed the association of genotype and allele frequencies between rheumatoid arthritis (RA) patients and the controls without RA using large samples size at 5383_5397del and 5509_5511delCAA variations of Tim-1 gene. We further investigated the relationships among these variations to C-reactive protein (CRP) and rheumatoid factor (RF) levels in RA patients. Although these factors were not associated with exon 4 variations in RA patients, the genotype and allele frequencies of 5383_5397del variation site (P = 0.015 and 0.014, respectively) as well as 5509_5511delCAA variation site (P = 0.0002 and 0.0001, respectively) in RA patients were significantly different from those in the non-RA controls. Our results strongly suggest that the variations of Tim-1 exon 4 might be associated with the susceptibility to RA.

Adult↗

PubMed2003

The association of the exon 4 variations of Tim-1 gene with allergic diseases in a Korean population.

The family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is identified to be expressed on T cells. A member of Tim family, TIM-1, is considered as a membrane protein that is associated with the development of Th2 biased immune responses and may be selectively expressed on Th2 cells. In the present study, we analyzed the association of allele and genotype frequencies between asthma or atopy patients and the controls without asthma and atopy using large sample size at 5383_5397del and 5509_5511delCAA variations of Tim-1 gene. Although the allele frequency of 5509_5511delCAA variation in asthma was not significantly different (P=0.085), the genotype of 5509_5511delCAA variation in asthma was significantly associated with the susceptibility to asthma (P=0.037). The genotype and allele frequencies of 5383_5397del variation in atopic dermatitis were significantly different from those in the non-asthmatic and non-atopic controls (P=0.005 and P=0.002, respectively). Our results strongly suggest that the 5383_5397del variation site of Tim-1 exon 4 might be associated with atopic dermatitis susceptibility.

Asthma↗

PubMed2003

Molecular variations in the promoter and coding regions of human Tim-1 gene and their association in Koreans with asthma.

The family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is identified to be expressed on T cells. A member of Tim family, TIM-1, was considered as a membrane protein that is associated with the development of helper T cell (Th2) biased immune responses, and may be selectively expressed on Th2 cells. In the present study we performed single nucleotide polymorphism (SNP) scanning of the coding and promoter regions of human Tim-1 gene. We identified a total of ten SNPs including five novel SNPs (-1166C>G, -416G>C, -232A>G, 5365C>T, and 5529A>G) in the coding and promoter regions, one novel variation site (-2278_-2276dupATT) in the promoter region and three variations (5383_5397del, 5387_5389insAAC, and 5509_5511delCAA) in exon 4 of human Tim-1 gene. Our results suggest that the exon 4 variation site in human Tim-1 gene is associated with the susceptibility of allergic disease.

Asthma↗