Nowadays, to evaluate growth hormone(GH) deficiency-suspicious short stature, we usually use more than two kinds of provocative tests using various pharmacologic agents such as clonodine, L-dopa, insulin, etc. However, the importance of physiologic natural secretion of GH was recently approved. In the past, diagnosis of GH neurosecretory dysfunction was made by studying the 24-hour spantaneous GH secretion profile. But, because it is very clinically difficult, and so we measured and evaluated the mean GH concentrations of blood samples, obtained every 30 minutes during the first 3 hours' nocturnal sleep, instead of that. At the department of Pediatrics, Hanyang University Hospital from November, 1992 to February, 1994, we selected 34 GH deficiency-suspected children on the base of their growth data and bone age, etc. After GH stimulation with clonidine(100-150 ug/m2) and L-dopa(200-250 mg/m2), we measured their peak GH values by the immunoradiometric assay(IRMA) kit. And, we measured the mean GH concentrations of blood samples, obtained every 30 minutes during the first 3 hours noctumal sleep(22:OOPM-1:OOAM). RESULTS: 1. We analyzed the relationship between the mean of 3-hours' physiologic night-time surge of GH(X) and the phamacologically stimulated peak GH level(Y), except for the two neurosecretory dysfunction suspicious children. And so, for the 32 children, the relationship was Y=1.806X+ 3.177, r= 0.794, p<0.01. However, for all the tested children(34), the relationship is Y=1.709X+ 4.06, r=0.737, p<0.01. 2. We analyzed the relationship between the peak of 3-hours' physiologic night-time surge of GH(X) and the phamacologicaUy stimulated peak GH level(Y), except for the two neurosecretory dysfunction suspieious children. And so, for the 32 children, the relationship was Y=0.683X+ 3.686, r=737, p<0.01. CONCLUSION: For all the tested children(34), the relationship between the mean 3hr physiologic GH night time surge and stimulated peak GH value is Y=1.709X+4.06, r=0.737, p<0.01. The percentage of GH neurosecretory dysfunction is 5.8%(2/34). And, except for the two childrren, the relationship is more good, Y=1.806X+3.177, r=0,794, p<0.01. On the above relationship, the 3-hour GH night time-surge test might to give us some helpful information for the diagnosis of neurosecretory dysfunction.
Child* ; Diagnosis ; Growth Hormone* ; Humans ; Insulin ; Levodopa ; Pediatrics

The aim of this study was to identify the bacteria isolated from acute endodontic lesions by cell culture and 16S rDNA sequencing. The necrotic pulpal tissue was collected from 17 infected root canals, which were diagnosed as being either an acute pulpitis or acute periapical abscess. Samples were collected aseptically from the infected pulpal tissue of the infected root canals using a barbed broach and a paper point. The cut barbed broaches and paper points were transferred to an eppendorf tube containing 500 ul of 1 X PBS. The sample solution was briefly mixed and plated onto a BHI-agar plate containing 5% sheep blood. The agar plates were incubated in a 37degrees C anaerobic chamber for 7 days. The bacteria growing on the agar plate were identified by 16S rRNA coding gene (rDNA) cloning and sequencing at the species level. Among the 71 colonies grown on the agar plates, 56 strains survived and were identified. In dental caries involving the root canals, Streptococcus spp. were mainly isolated. Actinomyces, Clostridia, Bacteroides and Fusobacteria were isolated in the periapical lesion without dental caries. Interestingly, two new Actinomyces spp. (ChDC B639 and ChDC B631) were isolated in this study. These results showed that there was diversity among the species in endodontic lesions. This suggests that an endodontic infection is a mixed infection with a polymicrobial etiology. These results may offer the bacterial strains for pathogenesis studies related to an endodontic infection.
Actinomyces ; Agar ; Bacteria* ; Bacteroides ; Cell Culture Techniques ; Clinical Coding ; Clone Cells ; Cloning, Organism ; Coinfection ; Dental Caries ; Dental Pulp Cavity* ; DNA, Ribosomal ; Fusobacteria ; Periapical Abscess* ; Pulpitis* ; Sheep ; Streptococcus ; Tooth*

The aim of this study was to investigate the susceptibility of mutans streptococci (S. mutans and S. sobrinus) and Streptococcus anginosus, for seven antibiotics, penicillin G, amoxicillin, ciprofloxacin, cefuroxime, erythromycin, bacitracin, and vancomycin. The minimum inhibitory concentration (MIC) of seven antibiotics against 3 species (type strains) of mutans streptococci and S. anginosus, 10 strains (wild type) of S. mutans, 7 strains (wild type) of S. sobrinus, and 11 strains (wild type) of S. anginosus, were measured by broth dilution method. All of the type strains of mutans streptococci and S. anginosus had the same susceptibility for penicillin G, amoxicillin, cefuroxime and bacitracin. Type strain of S. anginosus was sensitive in ciprofloxacin, but those of mutans streptococci were not. All of the clinical isolates of mutans streptococci and S. anginosus had the same susceptibility for the seven antibiotics. Our data reveal that mutans streptococci and S. anginosus have similar antibiotic-resistant character. In addition, these results may offer the basic data to verify the antibiotic-resistant mechanism of mutans streptococci and S. anginosus.
Amoxicillin ; Anti-Bacterial Agents ; Bacitracin ; Cefuroxime ; Ciprofloxacin ; Dental Plaque* ; Erythromycin ; Microbial Sensitivity Tests ; Penicillin G ; Penicillins ; Streptococcus anginosus* ; Streptococcus* ; Vancomycin

Polyphenon 60 refers to the mixture of catechins present in green tea. The aim of this study was to investigate the antimicrobial activities of polyphenon 60 against 4 strains of Streptococcus mutans and 2 strains of Streptococcus sorbrinus, which are the major causative bacteria of dental caries. The minimum bactericidal concentration (MBC) values of polyphenon 60 for S. mutans and S. sobrinus were determined and the effect of biofilm formation inhibition of that was evaluated. The MBC value of polyphenon 60 against the bacterial strains was 2.5 mg/ml except for one particular strain, S. mutans KCOM 1128 for which the value was 1.25 mg/ml. The results of biofilm formation inhibition assay revealed that polyphenon 60 inhibited biofilm formation more than 90% at a concentration of 2.5 mg/ml. It was apparent that polyphenon exhibited biofilm formation inhibition activity along with bactericidal effect against S. mutans and S. sobrinus. Therefore, it is proposed that polyphenon 60 as one of the components of bactericidal agents could be useful in developing oral hygiene products, toothpaste or gargling solution.
Bacteria ; Biofilms ; Catechin ; Dental Caries ; Oral Hygiene ; Streptococcus mutans ; Streptococcus sobrinus ; Streptococcus ; Tea ; Toothpastes

This study aimed to develop Lautropia mirabilis-specific quantitative real-time polymerase chain reaction (qPCR) primers based on the sequence of DNA-directed RNA polymerase subunit beta gene. The PrimerSelect program was used in designing of the qPCR primers, RTLam-F4 and RTLam-R3. The specificity of the qPCR primers were performed by conventional PCR with 37 strains of 37 oral bacterial species, including L. mirabilis. The sensitivity of the primers was determined by qPCR with the serial dilution of purified genomic DNA of L. mirabilis KCOM 3484, ranged from 4 ng to 4 fg. The data showed that the qPCR primers could detect only L. mirabilis strains and as little as 40 fg of genome DNA of L. mirabilis KCOM 3484. These results indicate that this qPCR primer pair (RTLam-F4/ RTLam-R3) may be useful for species-specific detection of L. mirabilis in epidemiological studies of oral bacterial infectious diseases such as periodontal disease.

This study aimed to develop Lautropia mirabilis-specific quantitative real-time polymerase chain reaction (qPCR) primers based on the sequence of DNA-directed RNA polymerase subunit beta gene. The PrimerSelect program was used in designing of the qPCR primers, RTLam-F4 and RTLam-R3. The specificity of the qPCR primers were performed by conventional PCR with 37 strains of 37 oral bacterial species, including L. mirabilis. The sensitivity of the primers was determined by qPCR with the serial dilution of purified genomic DNA of L. mirabilis KCOM 3484, ranged from 4 ng to 4 fg. The data showed that the qPCR primers could detect only L. mirabilis strains and as little as 40 fg of genome DNA of L. mirabilis KCOM 3484. These results indicate that this qPCR primer pair (RTLam-F4/ RTLam-R3) may be useful for species-specific detection of L. mirabilis in epidemiological studies of oral bacterial infectious diseases such as periodontal disease.

The aim of this study was to identify strain KCOM 1265 isolated from subgingival plaque at the species level by comparing 16S ribosomal RNA gene (16S rDNA) and genome sequences. The whole genome of strain KCOM 1265 was extracted using the phenol–chloroform extraction method. 16S rDNA was amplified using polymerase chain reaction and sequenced using the dideoxy chain termination method. Pairwise genome comparison was performed using average nucleotide identity (ANI) and genome-to-genome distance (GGD) analyses. The data showed that the percent similarity of 16S rDNA sequence of strain KCOM 1265 was 99.6% as compared with those of Fusobacterium polymorphum ATCC 10953T and Fusobacterium hwasookii KCOM 1249T. The ANI values of strain KCOM 1265 with F. polymorphum ATCC 10953T and F. hwasookii KCOM 1249T were 95.8% and 93.0%, respectively. The GGD values of strain KCOM 1265 with F. polymorphum ATCC 10953T and F. hwasookii KCOM 1249T were 63.9% and 49.6%, respectively. These results indicate that strain KCOM 1265 belongs to F. polymorphum.

Human periodontal ligament fibroblast(hPDLF) is very important to cure periodontal tissue because it can be diverged into various cells. This study examined the expression of MMP-1, TIMP-1, periodontal ligament specific PDLs22, Type I collagen, Fibronectin, TIMP-2, telomerase mRNA in a replicative senescence of hPDLF. The periodontal ligament tissue was obtained from periodontally healthy and non-carious human teeth extracted for orthodontic reasons at the Chosun University Hospital of Dentistry with the donors' informed consent. The hPDLF cells were cultured in a medium containing Dulbecco's modified Eagle medium(DMEM, Gibco BRL, USA) supplemented with 10% fetal bovine serum(FBS, Gibco BRL, USA) at 37C in humidified air with 5% CO2. For the reverse transcription-polymerase chain reaction(RT-PCR) analysis, the total RNA of the 2, 4, 8, 16, 18, and 21 passage cells was extracted using a Trizol Reagent(Invitrogen, USA) in replicative hPDL cells. Two passage cells, i.e. young cells, served as the control, and beta-actin served as the internal control for RT-PCR The results of this study about cell morphology and gene expression according to aging of hPDLF using RT-PCR method are as follows: 1. The size of hPDLF was increased with aging and it was showed that the hPDLF was dying in the final passage. 2. PDLs22 mRNA was expressed in young hPDLF of the two, four, and six passage. 3. TIMP-1 mRNA was expressed in young hPDLF of the two and four passage. 4. There was a tendency that MMP-1 mRNA was weakly expressed over eighteen. 5. Type 1 collagen mRNA was expressed in almost all passages, but it was not expressed in the final passage. 6. Fibronectin mRNA was observed in all passages and it was weakly expressed in the final passage. 7. TIMP-2 and telomerase mRNA were not expressed in this study. Based on above results, it was observed that PDLs22, Type 1 collagen, Fibronectin, MMP-1. and TIMP-1 mRNA in hPDLF were expressed differently with aging. The study using the hPDLF that is collected from healthy patients and periodontitis patients needs in further study.
Humans

Human periodontal ligament fibroblast(hPDLF) is very important to cure periodontal tissue because it can be diverged into various cells. This study examined the expression of MMP-1, TIMP-1, periodontal ligament specific PDLs22, Type I collagen, Fibronectin, TIMP-2, telomerase mRNA in a replicative senescence of hPDLF. The periodontal ligament tissue was obtained from periodontally healthy and non-carious human teeth extracted for orthodontic reasons at the Chosun University Hospital of Dentistry with the donors' informed consent. The hPDLF cells were cultured in a medium containing Dulbecco's modified Eagle medium(DMEM, Gibco BRL, USA) supplemented with 10% fetal bovine serum(FBS, Gibco BRL, USA) at 37C in humidified air with 5% CO2. For the reverse transcription-polymerase chain reaction(RT-PCR) analysis, the total RNA of the 2, 4, 8, 16, 18, and 21 passage cells was extracted using a Trizol Reagent(Invitrogen, USA) in replicative hPDL cells. Two passage cells, i.e. young cells, served as the control, and beta-actin served as the internal control for RT-PCR The results of this study about cell morphology and gene expression according to aging of hPDLF using RT-PCR method are as follows: 1. The size of hPDLF was increased with aging and it was showed that the hPDLF was dying in the final passage. 2. PDLs22 mRNA was expressed in young hPDLF of the two, four, and six passage. 3. TIMP-1 mRNA was expressed in young hPDLF of the two and four passage. 4. There was a tendency that MMP-1 mRNA was weakly expressed over eighteen. 5. Type 1 collagen mRNA was expressed in almost all passages, but it was not expressed in the final passage. 6. Fibronectin mRNA was observed in all passages and it was weakly expressed in the final passage. 7. TIMP-2 and telomerase mRNA were not expressed in this study. Based on above results, it was observed that PDLs22, Type 1 collagen, Fibronectin, MMP-1. and TIMP-1 mRNA in hPDLF were expressed differently with aging. The study using the hPDLF that is collected from healthy patients and periodontitis patients needs in further study.
Humans

The purpose of this study is to survey the frequency of mutans streptococci species and biotypes isolated from dental plaque in Korean adolescents and adults and the relationship between species of mutans streptococci and DMFT index. The dental plaque samples were collected from the anterior and molar teeth of both of jaws in the 47 human subjects (aged 14 to 29.3 years, average age was 20.2 years). A dental examination was performed for DMFT with the WHO caries diagnostic criteria. The mutans streptococci were cultured selectively on mitis-salivarius bacitracin (MSB) agar plates. The bacterial colonies growing on the MSB plates were then identified with biochemical tests (for biotyping) as well as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) targeting dextranase gene (dex) (for the determination of species). The data showed that the prevalence of Streptococcus mutans, S. sobrinus, and S. downei were 93.6%, 12.8%, and 8.5%, respectively. The biotype I (87.4%) and biotype IV (19.1%) were the most frequently detected. The DMFT scores of adolescents and adults harboring both S. mutans and S. sobrinus were significantly higher than those for S. mutans alone (p < 0.05). Above results revealed that S. mutans and biotype I were frequently detected in Korean adolescents and adults. In addition, the results suggest that subjects having plaques compared of both S. mutans and S. sobrinus may be more susceptible to caries than those having S. mutans alone.
Adolescent* ; Adult* ; Agar ; Bacitracin ; Dental Plaque* ; Dextranase ; Humans ; Jaw ; Molar ; Prevalence ; Streptococcus mutans ; Tooth