Soon Chul Myung

Expression of resistin in the prostate and its stimulatory effect on prostate cancer cell proliferation

What’s known on the subject? and What does the study add?

Fluoxetine Induces Apoptosis in Ovarian Carcinoma Cell Line OVCAR‐3 Through Reactive Oxygen Species‐Dependent Activation of Nuclear Factor‐κB

The apoptotic effect of fluoxetine (FLX), an antidepressant, against human epithelial ovarian cancer cell lines OVCAR-3 and SK-OV-3 was investigated in relation to the mitochondria-mediated cell death process and nuclear factor (NF)-kappaB activation. FLX-induced mitochondrial membrane permeability change and formation of reactive oxygen species, leading to cell death. FLX-induced increase in mitochondrial Bax levels, decrease in cytosolic Bid and Bcl-2 levels, loss of the mitochondrial transmembrane potential, cytochrome c release, caspase-3 activation and up-regulation of p53. Oxidant scavengers and Bay 11-7085 [an inhibitor of nuclear factor kappaB (NF-kappaB) activation] prevented the FLX-induced cell death, increase in phosphorylated inhibitory kappaB-alpha and NF-kappaB p65 levels, and binding of NF-kappaB p65 to DNA. Results from this study suggest that FLX may exhibit apoptotic effect against ovarian cancer cell lines by inducing the mitochondrial membrane permeability change, which leads to cytochrome c release and subsequent caspase-3 activation, through reactive oxygen species-dependent activation of NF-kappaB.

Correlation of metabolic syndrome with urinary stone composition

To determine the correlation between metabolic syndrome and the distribution of stone components in patients with urolithiasis.

The clinical significance in healthy men of the association between obesity related plasma hemodilution and tumor marker concentration.

PURPOSE We investigated the association between body mass index and the concentration of tumor markers including carcinoembryonic antigen, alpha-fetoprotein, the carbohydrate antigen 19-9 and prostate specific antigen, as well as the association between body mass index changes and tumor marker concentration changes in a population of healthy men. MATERIALS AND METHODS We evaluated data on 8,776 men screened for tumor markers (carcinoembryonic antigen, alpha-fetoprotein, carbohydrate antigen 19-9 and prostate specific antigen) at least 3 times annually during an annual examination from 2001 to 2007. We assessed the tumor marker test findings for a trend in the age, alanine aminotransferase and creatinine adjusted tumor marker concentration by body mass index. We used multivariate regression analysis to determine whether a change in body mass index was associated with a tumor marker concentration change over time using calculated tumor markers, body mass index, creatinine and alanine aminotransferase concentration change per year. RESULTS After adjusting for age, creatinine and alanine aminotransferase a higher body mass index was associated with lower prostate specific antigen (p for trend <0.001), carcinoembryonic antigen (p for trend <0.001) and carbohydrate antigen 19-9 (p for trend <0.001). On multivariate regression analysis each 1 kg/m(2) of body mass index gain per year was associated with a -0.011 ng/ml change in prostate specific antigen concentration, a -0.030 ng/ml change in carcinoembryonic antigen concentration and a -0.192 IU/ml change in carbohydrate antigen 19-9 concentration per year. CONCLUSIONS In this cohort of healthy men hemodilution from increased plasma volume may be responsible for the observed decreased tumor marker concentration in men with a higher body mass index. In addition, an increase in body mass index may predict a lower tumor marker concentration in an individual.

Relationship Between Serum Prostate-Specific Antigen Levels and Components of Metabolic Syndrome in Healthy Men

OBJECTIVES To assess the correlation between age, body mass index, systolic and diastolic blood pressure (BP), triglycerides, high-density lipoprotein (HDL), and fasting blood glucose (FBG) and the serum prostate-specific antigen (PSA) level and to determine the significant factors for predicting the serum PSA level in men with a low risk of prostate cancer. METHODS A total of 38 356 healthy male employees of the Korea Electric Power Corporation who were <60 years old and had a serum PSA level of <4 ng/mL were enrolled in this study from January 2002 to December 2006. Their BP, body weight, and body height were measured, and biochemical analyses of FBG, triglycerides, HDL, and serum PSA were performed. RESULTS The mean age +/- standard deviation was 44.38 +/- 7.90 years; the mean serum PSA level was 0.89 +/- 0.51 ng/mL; and the incidence of metabolic syndrome was 25.8%. On univariate analysis, significant correlations were noted between the serum PSA level and body mass index, diastolic BP, HDL, and FBG (P < .05). Multiple logistic regression analyses using 4 percentiles (10th, 25th, 75th, and 90th percentile) of the serum PSA level revealed trends for a positive association between older age and diastolic BP and the serum PSA level. The body mass index, HDL, and FBG correlated negatively with the serum PSA level. CONCLUSIONS These results suggest that the serum PSA level is significantly influenced by age and some components of the metabolic syndrome (obesity, diastolic BP, HDL, and FBG).

Modulation of human β-defensin-2 expression by 17β-estradiol and progesterone in vaginal epithelial cells

We investigated the expression of HBD-1 and -2 in vaginal epithelial cells treated with lipopolysaccharide (LPS) and the effects on HBD-2 expressions by 17beta-estradiol and progesterone. Primary vaginal epithelial cells were isolated from a segment of normal anterior vaginal wall obtained during vaginoplasty and were cultured in keratinocyte growth medium and were allowed to undergo their 3rd passage. Expression of HBD-1 and -2 by different stimuli using LPS 0.5 microg/ml, 17beta-estradiol 2 nM and progesterone 1 microM was measured by RT-PCR, ELISA and real-time RT-PCR, respectively. HBD-1 was produced constitutively in vaginal epithelial cells and the production of HBD-1 was not influenced by LPS, 17beta-estradiol and progesterone, but the production of HBD-2 was increased inducibly by LPS. 17beta-Estradiol and progesterone did not change the production of HBD-2 in normal state, but 17beta-estradiol increased the production of HBD-2 and progesterone suppressed the production of HBD-2 under the circumstances with infection. The HBD-2 plays an important role at innate host defense on genitourinary tract. The lacks of estrogen during menopause or uses of a progesterone-based oral contraceptive in sexually active women may influence production of HBD-2 in vaginal epithelium and may increase susceptibility to bacterial vaginitis or recurrent UTI.

Identification of the cpsA gene as a specific marker for the discrimination of Streptococcus pneumoniae from viridans group streptococci.

Streptococcus pneumoniae, the aetiological agent of pneumonia and non-gonococcal urethritis, shares a high degree of DNA sequence identity with the viridans group of streptococci, particularly Streptococcus mitis and Streptococcus oralis. Although their clinical and pathological manifestations are different, discrimination between S. pneumoniae and its close viridans cocci relatives is still quite difficult. Suppression subtractive hybridization was performed to identify the genomic differences between S. pneumoniae and S. mitis. Thirty-four resulting S. pneumoniae-specific clones were examined by sequence determination and comparative DNA sequence analysis using blast. S. pneumoniae-specific primers were subsequently designed from one of the clonal DNA sequences containing the cps gene (coding for capsular polysaccharide biosynthesis). The primer specificities were evaluated using 49 viridans streptococci including 26 S. pneumoniae, 54 other streptococci, 14 Lactococcus species, 14 Enterococcus species and three Vagococcus species, and compared with the specificities of previously described autolysin (lytA), pneumolysin (ply), Spn9802 and Spn9828 primers. The newly designed cpsA-specific primer set was highly specific to S. pneumoniae and was even better than the existing primers. These findings may help improve the rapid identification and differentiation of S. pneumoniae from closely related members of the viridans group streptococci.

Association between serum prostate-specific antigen level, liver function tests and lipid profile in healthy men

To assess the association between serum prostate‐specific antigen (PSA) level and age, liver function tests (LFTs) including alkaline phosphatase (ALP), total bilirubin (TB), lipid profile (total cholesterol, TC, triglycerides, TG, high‐density lipoprotein, HDL) and fasting blood sugar (FBS), and to determine the significant factors for predicting the serum PSA level in men with a low risk of having prostate cancer.

Flavobacterium ponti sp. nov., isolated from seawater

A Gram-stain-negative, non-flagellated, non-gliding, yellow-pigmented and rod-shaped bacterial strain, designated GSW-R14(T), was isolated from seawater of Geoje Island in the South Sea, Korea. Strain GSW-R14(T) grew optimally at 25 °C, at pH 7.0-8.0 and in the presence of 2 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain GSW-R14(T) belonged to the genus Flavobacterium, joining Flavobacterium gelidilacus LMG 21477(T) by a bootstrap resampling value of 100 %. Strain GSW-R14(T) exhibited 97.6 % 16S rRNA gene sequence similarity to F. gelidilacus LMG 21477(T) and similarities of 91.2-95.2 % to other members of the genus Flavobacterium. Strain GSW-R14(T) contained MK-6 as the predominant menaquinone. The fatty acid profile of strain GSW-R14(T) was similar to that of F. gelidilacus LMG 21477(T). The DNA G+C content of strain GSW-R14(T) was 31.4 mol% and its DNA-DNA relatedness with F. gelidilacus LMG 21477(T) was 31 %. Strain GSW-R14(T) could be distinguished from F. gelidilacus and the other species of the genus Flavobacterium by its phylogenetic and genetic distinctiveness and by several phenotypic properties. On the basis of these data, strain GSW-R14(T) is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium ponti sp. nov. is proposed; the type strain is GSW-R14(T) (=KCTC 22802(T) =CCUG 58402(T)).

Impact of Changing Trends in Medical Therapy on Surgery for Benign Prostatic Hyperplasia Over Two Decades

Purpose Following the introduction of medical therapy for benign prostatic hyperplasia (BPH), we determined the effect of the change in trends in medical therapy on the indication and outcome of surgical intervention for BPH. Materials and Methods We compared the basic characteristics of, weight of resected tissue of, transfusions in, and postoperative complications of patients who underwent surgery between 1985 and 1989 (before the advent of medical therapy for BPH), between 1995 and 1999 (when medical therapy was developed and became widely used as alternative treatment), and between 2005 and 2009 (when medical therapy superseded surgical intervention to become first-line treatment and when combination therapy became widely adopted). Results At our institution, the mean age and BMI of patients increased over the past two decades (p<0.001). Hypertension, operation history, and other comorbidities also increased significantly (p<0.001, p=0.005, and p<0.001, respectively). The indications for surgery in 1985 to 1989, 1995 to 1999, and 2005 to 2009 were as follows: acute urinary retention in 34.7%, 20.2%, and 15.1% of patients and symptomatic deterioration in 61.1%, 72.3%, and 73.0% of patients, respectively. Prostate volume and the weight of resected tissue increased from 34.4±14.5 ml to 61.3±32.4 ml and from 7.2±6.4 g to 10.8±7.6 g, respectively, over two decades. Patients who underwent surgery in 2005 to 2009 had their catheters removed earlier (p<0.001). Secondary hemorrhage within four postoperative weeks and repeat transurethral resection of the prostate within 1 year decreased significantly (p=0.03 and p=0.003, respectively). No statistically significant change in impaired detrusor contractility was found (p=0.523). Conclusions Although patients who underwent surgery were older after widespread use of medical therapy for BPH, advancements in surgical techniques have benefitted these patients.