• Korean Journal of Clinical Laboratory Science
• /
• v.38 no.1
• /
• pp.34-37
• /
• 2006

Beta-hemolytic streptococci (BHS) are frequently isolated pathogens in clinical microbiology laboratories. Among them, Group C, G and F streptococci infrequently cause respiratory infections, but they often invade other sites. Patients with underlying diseases are prone to be infected by the organisms and some of them can be fatal. Therefore, combination tests of serological and biochemical tests are needed to correct the identification of non-A, B streptococci because to various species belong to this species. The aim of this study was to investigate the isolation rates of strains and distribution of serogroup C, G and F streptococci at Wonju Hospital during the period of 2003-2004. 133 clinical isolates of group C, G and F streptococci were examined. Of them, 13 (9.8%) were group C, 41 (31.8%) were group F, 79 (59.4%) were group G. The prevalent isolation of the strains by serogroup were: group C, Streptococcus constellatus (38.5%); group F, Streptococcus anginosus (56.1%), Streptococcus constellatus (26.9%); group G, Streptococcus anginosus (54.4%), Streptococcus dysgalatiae subsp. equisimilis (26.5%). Overall, the most frequently isolated BHS was Streptococcus anginosus (51.2%).

• Korean Journal of Microbiology
• /
• v.53 no.3
• /
• pp.225-226
• /
• 2017

Streptococcus mitis is a Gram-positive, facultative anaerobic, alpha-hemolytic, and nonmotile cocci. S. mitis is a viridans streptococci and a normal commensal of throat, nasopharynx, and mouse and is associated with infective endocarditis, septicemia, and meningitis. S. mitis KCOM 1350 (= ChDC B183) was isolated from a human mandibular osteomyelitis lesion. Here, we present the complete genome sequence of S. mitis KCOM 1350.

• Pediatric Infection and Vaccine
• /
• v.2 no.2
• /
• pp.180-185
• /
• 1995

1. Purpose The accurate diagnosis and proper treatment of group A streptococcus should be emphasized concerning about possible development of late sequelae, such as acute rheumatic fever and acute glomerulonephritis. We would like to know the recover rate of beta-hemolytic streptococci by throat swab culture at the in-patient 2. Methods The throat swab cultures and filled up flow-sheets were undertaken on 619 children who had admitted to hospital, KyungHee university hospital from may 1994 to april 1995 prospectively. At the same time on admission, throat culture was performed. 3. Results The highest recover rate of BHS(Beta-Hemolytic Streptococci)and GAS(Group A Streptococci) were seen in above 10 years old, as 9.1% and 1.9%. BHS were obtained in 39 cases(6.3%) among 619 children while GAS was obtained in 3 cases (0.4%). Among 39 specimens of BHS, 33 specimens were classified as non-grouping streptococcus. 4. Conclusion The poor recovery rate of GAS inpatient compared with normal carrier rate is likely due to possible antibiotic abuse, errors in processing samples, and epidemiologic factors such as seasons and geographic areas. It is necessary to evaluate the clinical significance of non-A,B,C,G streptococcal infections and carriers.

• Journal of Veterinary Clinics
• /
• v.23 no.2
• /
• pp.158-163
• /
• 2006

This work describes an outbreak of strangles due to Streptococcus equi subsp. equi in 1 to 2 years old Thoroughbred horses. A total of 7 samples were collected from 5 horses in two different horse farms during 2003. Six ${\beta}$-hemolytic colonies selected from each sample were identified by biochemical tests using API STREPTO followed by PCR amplification which is able to recognize unique region of SeM gene of S. equi subsp. equi. All colonies selected from the ruptured lymphadenitis of 2 horses in farm A were identified as S. dysgalactiae subsp. equisimillis. It seems to be secondary infection because the sampling sites have been already opened and the horses have been treated with antibiotics for a week. All colonies from 2 submandibular lymphadenitis samples in Farm B were S. equi subsp. equi while the isolates from 3 nasal discharges in this farm were mixed with S. equi subsp. zooepidemicus.

• Journal of fish pathology
• /
• v.36 no.2
• /
• pp.277-286
• /
• 2023

Korean rockfish, Sebastes schlegelii, is a representative bony fish that belongs to the family Scorpaenidae and the order Scorpaeniformes. It has high ecological and economic value and is widely cultivated in many East Asian countries, including South Korea, Japan and China. One of streptococci, Streptococcus iniae, is Gram-positive cocci with a negative reaction for catalase and oxidase. The Korean rockfish shows clinical signs when infected with S. iniae, such as body darkening, bleeding, enlarged kidneys, blurred eyes, abdominal distension, etc., ultimately leading to death. The Korean rockfish causes significant economic losses every year in South Korea due to streptococcosis. In this study, we identified bacteria from the fish using polymerase chain reaction and conducted analyses of hemolytic activity and biochemical tests using API 20 STREP and API ZYM systems. Results of confirming the hemolytic activity (n=4) observed in alpha-type hemolysis (25%), beta-type hemol- ysis (50%), and gamma-type hemolysis (25%) of isolates. The biochemical test results exhibited sig- nificant variation among S. iniae. Additionally, we performed intraperitoneal injection with S. iniae in the fish and analyzed the phylogenetic tree using housekeeping genes of S. iniae, including cpsD, arcC, glnA, groEL, gyrB, mutS, pheT, prkC, rpoB, and tkt, via multilocus sequence typing (MLST). The lethal dose (LD₅₀) showed strong pathogenicity, such as 3.34 × 10 colony-forming unit (CFU)/ml for 23FBStr0601 strain and 7.16 × 10 CFU/ml for 23FBStr0602 strain. 23FBStr0603 strain showed relatively low pathogenicity at 1.73 × 10⁵ CFU/ml. The strains 23FBStr0601 and 23FBStr0602, which showed strong pathogenicity, clustered into one monophyletic group. The 23FBStr0603 strain showed weak pathogenicity and formed a monophyletic group with KCTC 3657.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.16 no.1
• /
• pp.104-111
• /
• 1994

Necrotizing fascitis is a severe soft tissue infection characterized by extensive necrosis of superficial fascia, suppurative fascitis, vascular thrombosis, widespread undermining of surrounding tissues. Associated systemic problems are widespread undermining of surrounding tissues, Associated systemic problems are common, with chronic alcoholism and diabetes being most prominent. Most commonly this disease presents in the extremities, trunk, and perineum. Necrotizing fascitis of dental origing is rare and its fulminating clinical course is not well documented in the dental literature. The present report is a case of necrotizing fascitis following vital extirpation of the pulp in a patient with uncontrolled diabetes mellitus and liver cirrhosis. Originally throught to be caused by hemolytic streptococcus organism or stphylococcus aureus, advances in anaerobic culturing have shown it to be a synergistic bacterial infection involving aerobic and ovligate anaerobes. it is relatively rare in relatively rare in haea and neck regions. If it was not diagnosed and treated in early stages, necrotizing fascitis can be potentially fetal, with a mortality rate approaching 40%. It's treatment requires early recognition, prompt and aggressive surgical debriment and proper supportive cares, such as, antibiotic therapy, fluid resuscitation and correction of metabolic and electrolyte disorder, resolving of the underlying systemic disease. Recently, we experienced two cases of necrotizing fascitis in cervicofacial region, One patient was 60 years old male with uncontrolled Diabetes Mellitus and other patient was 48 years old with steroid therapy during 30 years. Local surgical wound healing was successful but, patients were died after admission, because of lung abscess, gastrointestinal bleeding, septic shock and respiration hold.

• Pediatric Infection and Vaccine
• /
• v.6 no.2
• /
• pp.194-202
• /
• 1999

Background : Group B ${\beta}$-hemolytic Streptococcus(GBS) has been the major pathogen of neonatal sepsis in western country. In contrast, GBS has played little role in neonatal sepsis in Korea. But recently, neonatal GBS infections are encountered more frequently. It is important to characterize the clinical and epidemiological features of GBS infection in Korean children. Methods: We reviewed retrospectively the medical records of twenty-seven infants and children with GBS infection experienced at the Seoul National University Children's Hospital during 14 year-period from June, 1985 to June, 1999. Fourteen strains isolated from blood and cerebrospinal fluid were serotyped. Minimum inhibitory concentrations of 10 strains were determined by agar dilution method for penicillin, ampicillin, ampicillin with sulbactam, cefarolin, cefuroxime, and cefuiaxone. Results: The numbers of cases with GBS infection increased in 1990s. Among twenty seven cases, twenty-five cases were under three months of age and both of two cases with underlying disease occurred at three years of age. All neonatal infections were late-onset type and meningitis predominated. Serotypes were III(6 strain), Ib(4), Ia(l) and V(2). All of the strain were susceptible to all of the antibiotics tested. Conclusion: GBS infections in infants were increasingly recognized. GBS should be considered as an etiological agent of neonatal sepsis or meningitis in Korea. Maternal screening and prophylactic antibiotic therapy may be considered.

• Journal of fish pathology
• /
• v.4 no.2
• /
• pp.71-77
• /
• 1991

From August to October of 1991, a bacterial disease occurred in cultured flounder, of 0 age Paralichthys olivaceus, in Cheju-do. Typical symptoms of the diseased fish were the hemorrage of the opercle, discoloration of the body, exophthalmus and hemorrhage of the eyes. The causative organism isolated from diseased fish was identified as a $\beta$-hemolytic Streptococcus. This bacterium was not identical with any known Streptococcus species listed in Bergey's Manual of Determinative Bacteriology 8th edition. However there was a close similarity between this species and Streptococcus sp. isolated from flounder and reported by Tashio (1983). The isolated bacteria streptococcus sp. showed very high sensitivity to the SM and EM, however, it resisted to the high concentration of Penicillin. In the pathagenicity analysis, about $1.1{\times}10^9$, $1.1{\times}10^7$, $1.1{\times}10^5$, $1.1{\times}10^3$, $1.1{\times}10^1cells$/100g B.W of isolated bacteria were injected percutaneouly. The results showed that this inoculation size $1.1{\times}10^3cells$/100g B.W was the threshold for the induction of mortality in pathogenicity analysis.

• Journal of fish pathology
• /
• v.19 no.1
• /
• pp.73-82
• /
• 2006

Streptococcal infections were considered as a serious problem because of significant economic losses in fish farm industry. We evaluated the efficacies of Streptococcus iniae vaccines in olive flounder, Paralichthys olivaceus. The vaccines were prepared from 10% neutral buffered formalin to give a final concentration of 0.3% or 3%, respectively. Fish were immunized by intraperitoneal injection of the experimental vaccines once or twice. Neither of the vaccines gave rise to any significant side effects. The antibody titers of booster immunized groups were significantly higher than those of prime immunized groups with both of the vaccines. According to formalin dosage, significantly increased antibody titers were produced by 3% formalin-killed cells (FKC) at 4weeks and 8weeks after prime and booster vaccination, respectively. Although the different levels of antibody production were showed by the vaccinated fish, the good protection obtained in challenge trials of the both vaccines. Fish immunized with 0.3% FKC once or twice had the relative percent survival (RPS) of 66.7% and 87.5%, respectively. Similarly, fish immunized with 3% FKC once or twice had the RPS of 70.0% and 77.0%, respectively. Further experiments are needed to study not only correlation between the antibody titers and RPS against S. iniae but also the side effects of high dose of formalin on antigenicity.

• Journal of Life Science
• /
• v.28 no.11
• /
• pp.1301-1315
• /
• 2018

We purified an antimicrobial peptide from the acidified hemocyte extract of Mytilus coruscus by $C_{18}$ reversed-phase high-performance liquid chromatography (RP-HPLC). The peptide was 4041.866 Da based on matrix-assisted laser desorption ionization time-of-flight mass spectrophotometer (MALDI-TOF/MS) and the 25 amino acids of the N-terminus sequence were identified. Comparison of this sequence of the purified peptide with the N-terminus sequences of other antimicrobial peptides revealed 100% identity with the mytilin B precursor of Mytilus coruscus. We also identified a 312 bp open-reading frame (ORF) encoding 103 amino acids based on the obtained amino acid residues. The nucleotide sequence of this ORF and the amino acid sequence also revealed 100% identity with the mytilin B precursor of Mytilus coruscus. We synthesized two antimicrobial peptides with an alanine residue in the C-terminus, and designated them mytilin B1 and B2. These two antimicrobial peptides showed antimicrobial activity against gram-positive bacteria, including Bacillus cereus and Streptococcus parauberis (minimal effective concentration, MECs $41.6-89.7{\mu}g/ml$), gram-negative bacteria, including Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Providencia stuartii, Pseudomonas aeruginosa, and Vibrio ichthyoenteri (MECs $7.4-39.5{\mu}g/ml$), and the fungus Candida albicans (MECs $26.0-31.8{\mu}g/ml$). This antimicrobial activity was stable under heat and salt conditions. Furthermore, the peptides did not exhibit significant hemolytic activity or cytotoxic effects. These results suggest that mytilin B could be applied as alternative antibiotic agent, and they add to the understanding of the innate immunity of hard-shelled mussels.