BACKGROUND: Streptococcus viridans group (SVG) is the normal flora of the upper respiratory tract, skin and genitourinary tract, and is the major causative agent isolated in 30-40% of bacterial endocarditis patients. However, SVG has not been properly identified to the species level for lack of diagnostic system which enables the accurate identification of SVG. Poyart et al. have recently described the identification of SVG to the species level by DNA sequencing of superoxide dismutase gene (sodAint). Using this method, we report here the identification of SVG isolated from the patients in Seoul National University Hospital within recent 2 years. METHODS: According to the method by Poyart et al., a set of two oligonucleotides, D1 (5 '-CCI TAY ICI TAY GAY GCI YTI GAR CC-3 ') and D2 (5 '-ARR TAR TAI GCR TGY TCC CAI ACR TC-3 ') were used as PCR primers, and PCR products of 480-bp size were obtained. The PCR products purified by MicroSpin S-400 HR Column were sequenced using ABI-PRISM 3700 Sequence Analyzer. D1 and D2 were used as sequencing primers. The clinical isolates were respectively identified as the species showing the greatest sequence homology which was demonstrated by the BLAST program provided by NCBI(USA). RESULTS: Clinical strains isolated from 26 patients who had shown two or more positive blood cultures were analyzed by DNA sequencing of superoxide dismutase gene, which showed 6 strains of S. salivarius, five S. oralis, four S. sanguis, three S. pasteuri, three S. equisimilis, two S. gordonii, one S. constellatus, one S. luteciae, and one S. mitis. S. salivarius and S. sanguis were clearly discriminated, while S. equisimilis and S. pyogenes were not. Species identification results by conventional method seldom corresponded to those by DNA sequencing. Among 7 patients suspected to have bacterial endocarditis, S. sanguis were isolated in 4 patients, and S. gordonii, S. oralis, S. pasteuri in one, respectively. Among 17 patients with liver cirrhosis or cancer, S. salivarius were isolated in 6 patients, and S. oralis in four. CONCLUSIONS: In this study, we could identify the species of SVG isolated from the patients with bacteremia; S. sanguis were frequently isolated from patients with bacterial endocarditis, while S. salivarius from ones with malignancy. These results imply that a different group of underlying diseases could show correspondingly different group of SVG species which cause bacteremia, and we suggest that further pathophysiological study on the correlations between underlying disease and the species of SVG be performed.
Bacteremia ; Endocarditis, Bacterial ; Homosexuality, Male ; Humans ; Liver Cirrhosis ; Male ; Oligonucleotides ; Polymerase Chain Reaction ; Respiratory System ; Seoul ; Sequence Analysis ; Sequence Analysis, DNA ; Sequence Homology ; Skin ; Streptococcus* ; Superoxide Dismutase ; Viridans Streptococci*

This in vitro study evaluated the detrimental effect of acute gamma (gamma)-irradiation on rat immature hippocampal neurons. Rat immature hippocampal neurons (0.5 day in vitro) were irradiated with 0~4 Gy gamma-rays. Cytotoxicity was analyzed using a lactate dehydrogenase release assay at 24 h after gamma-irradiation. Radiation-induced cytotoxicity in immature hippocampal neurons increased in a dose-dependent manner. Pre-treatments of pro-apoptotic caspase inhibitors and anti-oxidative substances significantly blocked gamma-irradiation-induced cytotoxicity in immature hippocampal neurons. The results suggest that the caspase-dependent cytotoxicity of gamma-rays in immature hippocampal cultured neurons may be caused by oxidative stress.
Amifostine/pharmacology ; Animals ; Antioxidants/pharmacology ; Caspase 3/metabolism/radiation effects ; Catechin/analogs & derivatives/pharmacology ; Cell Survival/radiation effects ; Cells, Cultured/cytology/enzymology/*radiation effects ; Dose-Response Relationship, Radiation ; Female ; *Gamma Rays ; Hippocampus/cytology/enzymology/*radiation effects ; L-Lactate Dehydrogenase/radiation effects ; Neurons/cytology/enzymology/*radiation effects ; Poly(ADP-ribose) Polymerases/drug effects ; Pregnancy ; Rats ; Rats, Sprague-Dawley

This study examined whether amifostine (WR-2721) could attenuate memory impairment and suppress hippocampal neurogenesis in adult mice with the relatively low-dose exposure of acute radiation syndrome (ARS). These were assessed using object recognition memory test, the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, and immunohistochemical markers of neurogenesis [Ki-67 and doublecortin (DCX)]. Amifostine treatment (214 mg/kg, i.p.) prior to irradiation significantly attenuated the recognition memory defect in ARS, and markedly blocked the apoptotic death and decrease of Ki-67- and DCX-positive cells in ARS. Therefore, amifostine may attenuate recognition memory defect in a relatively low-dose exposure of ARS in adult mice, possibly by inhibiting a detrimental effect of irradiation on hippocampal neurogenesis.
Acute Radiation Syndrome/drug therapy/*immunology/psychology ; Amifostine/*pharmacology/therapeutic use ; Animals ; Apoptosis/immunology ; Gamma Rays/*adverse effects ; Hippocampus/immunology ; Immunohistochemistry ; In Situ Nick-End Labeling ; Male ; Memory/*radiation effects ; Mice ; Mice, Inbred ICR ; Neurogenesis/immunology ; Radiation-Protective Agents/*pharmacology/therapeutic use

PURPOSE: Preformed circulating donor-specific antibodies (DSAs) immunologically challenge vascular endothelium and the bile duct. However, the liver is an immune-tolerant organ and can avoid immunological challenges. This study was undertaken to analyze the effects of DSAs after adult living donor liver transplantation (LDLT). METHODS: We retrospectively reviewed 219 LDLT patients' records treated at our center. RESULTS: Of the 219 patients, 32 (14.6%) were DSA (+) and 187 (85.4%) were DSA (-). Class I DSAs were present in 18 patients, class II in seven patients, and both in seven patients. Seven patients (3.2%) showed DSA to HLA-A, four (1.8%) to HLA-B, seven (3.2%) to HLA-DR, and 14 (6.4%) to two or more HLAs. More DSAs were observed in female recipients than male recipients in the DSA (+) group. The DSA (+) group showed significantly higher levels of class I and II panel reactive antibody (PRA) than did the DSA (-) group. No significant intergroup differences were found between incidences of primary nonfunction, acute rejection, vascular complication, or biliary complication. There were no significant differences in graft survival rates between the two groups. However, the recipients with multiple DSAs tended to have more acute rejection episodes and events of biliary stricture and lower graft survival rates than did patients in the DSA (-) group. CONCLUSION: In LDLT, the presence of multiple DSAs and high PRA seemed to be associated with poor graft outcomes, although our results did not reach statistical significance. Large cohort studies are necessary to clarify the impact of DSA and PRA in LDLT.
Adult ; Antibodies* ; Bile Ducts ; Cohort Studies ; Constriction, Pathologic ; Endothelium, Vascular ; Female ; Graft Survival ; HLA-A Antigens ; HLA-B Antigens ; HLA-DR Antigens ; Humans ; Incidence ; Liver Transplantation ; Liver* ; Living Donors* ; Male ; Retrospective Studies ; Transplantation* ; Transplants

Inhibin, which is important for normal gonadal function, acts on the pituitary gonadotropins to suppress folliclestimulating hormone (FSH) secretion. The level and cellular localization of the inhibin isotypes, alpha, beta(A) and beta(B), in the testis of mice were examined during postnatal development in order to determine if inhibin expression is related to testicular maturation. Mouse testes were sampled on postnatal days (PNDs) 1, 3, 6, 18, 48 and 120, and analyzed by Western blotting and immunofluorescence. Western blot analysis showed very low levels of inhibin alpha, beta(A) and beta(B) expression in the testes at days 1 to 6 after birth. The levels then increased gradually from PND 18 to 48-120, and there were significant peaks at PND 48. Inhibin alpha, beta(A) and beta(B) were detected in testicular cells during postnatal development using immunohistochemistry. The immunoreactivity of inhibin alpha was rarely observed in testicular cells during PND 1 to 6, or in the cytoplasmic process of Sertoli cells surrounding the germ cells and interstitial cells during PND 18 to 120. Inhibin beta(A) and beta(B) immunoreactivity was rarely observed in the testis from PND 1 to 6. On the other hand, it was observed in some spermatogonial cells, as well as in the interstitial space between PND 48 and PND 120. We conclude that the expression of inhibin isotypes increases progressively in the testis of mice with increasing postnatal age, suggesting that inhibin is associated with a negative feedback signal for FSH in testicular maturation.
Aging/*physiology ; Animals ; Gene Expression Regulation/*physiology ; Inhibin-beta Subunits/genetics/*metabolism ; Inhibins/genetics/*metabolism ; Male ; Mice ; Mice, Inbred ICR ; Protein Isoforms/metabolism ; Protein Transport/*physiology ; Testis/*metabolism