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Dive into the research topics where Seon Hwa Lee is active.

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Featured researches published by Seon Hwa Lee.


Clinical Biochemistry | 1999

Comparison of fatty acid profiles in the serum of patients with prostate cancer and benign prostatic hyperplasia

Yoon Jung Yang; Seon Hwa Lee; Sung Joon Hong; Bong Chul Chung

OBJECTIVE The role of dietary fatty acids (FAs) in benign and malignant prostatic diseases was investigated by comparing the composition value of serum fatty acids in the normal controls, and patients with prostate cancer (PC) and benign prostatic hyperplasia (BPH). Also, to estimate a possible association between PC risk and PUFAs, omega-3, omega-6 and omega-3/omega-6 FA composition ratios were compared among these groups. METHODS Serum samples were obtained from 24 BPH and 19 PC patients, and from 21 age-matched normal male subjects. The serum concentration of 21 fatty acids was determined using gas chromatography/mass spectrometry. RESULT The proportional values of saturated fatty acids (SFAs) groups demonstrated no specific difference between the control subjects and the patients. In the polyunsaturated fatty acids (PUFAs), we found that the omega-3 PUFAs level was significantly decreased in patient with BPH and PC and that the omega-6 PUFAs level was increased in PC only. The ratio of omega-3/omega-6 PUFAs decreased in the following order of normal, BPH, and PC. CONCLUSION It was proposed that the changed composition level of PUFAs including omega-3 and omega-6 PUFAs have certain relationship with both prostatic diseases. Therefore, the ratio of omega-3/omega-6 PUFAs also may have an important association with the benign and malignant status of prostatic disease.


Journal of Chromatography B: Biomedical Sciences and Applications | 1997

Urinary polyamine evaluation for effective diagnosis of various cancers

Ja Won Suh; Seon Hwa Lee; Bong Chul Chung; Jongsei Park

With a newly modified analytical method, the concentrations of free and acetylated urinary polyamines were simultaneously determined in a control group (32 cases) and patients with various types of cancers (104 cases, 20 males and 84 females) by gas chromatography-nitrogen-phosphorus detection. Significant concentration differences between normal subjects and various cancer patients were found. The various types of cancers (advanced gastric carcinoma, ovarian cancer, acute myelocyte leukemia, non-Hodgkins lymphoma) gave unique patterns of urinary polyamine profile as well as significant differences of concentration. To indirectly evaluate the possible involvement of enzymes, precursor-to-product concentration ratios were compared between controls and patients with various types of cancers.


Cancer Letters | 2003

Altered urinary profiles of polyamines and endogenous steroids in patients with benign cervical disease and cervical cancer

Seon Hwa Lee; Yoon Jung Yang; Kyung Mee Kim; Bong Chul Chung

The risk of cancer of the cervix is linked with sexual behavior. Although infectious agents, such as human papillomaviruses (HPVs) are implicated, these alone may be insufficient to induce the disease. We investigated the potential role of estrogen, androgen, and polyamine metabolism as co-factors in the development of cervical cancer. We obtained urine samples from patients with benign cervical disease (n=18) and cervical cancer (n=18) and from age-matched normal female subjects (n=25). For 11 polyamine determination, an improved and sensitive gas-chromatographic with nitrogen/phosphorus-detection (GC/NPD) procedure was used. The urinary levels of 25 androgens and corticoids and 16 estrogens were quantitatively determined by gas chromatography-mass spectrometry-selected ion-monitoring (GC/MS/SIM). In the patients with cervical cancer, the ratio of 16alpha-hydroxy estrone (16alpha-OH E1)/2-hydroxy estrone (2-OH E1), putrescine (Put)/N(1)-acetylspermidine (N(1)-acSpd) and 5beta-tetrahydrocortisol (THF)/5alpha-tetrahydrocortisol (5alpha-THF) were significantly increased in comparison to the values of the normal controls. These data suggest: (1) an increase of 16alpha-hydroxylation in estrogen metabolism; (2) the high activity of polyamine oxidase (PAO) in polyamine metabolism; and (3) the low activity of 5alpha-reductase in androgen metabolism may play a significant role in the development of cervical cancer. Although additional research is necessary, the combination of 16alpha-OH E1/2-OH E1 and THF/5alpha-THF may provide a dual marker for the discrimination of benign cervical disease and cervical cancer.


Cancer Letters | 1998

Estrogens and polyamines in breast cancer: their profiles and values in disease staging

Seon Hwa Lee; Soon Ok Kim; Hy-De Lee; Bong Chul Chung

The urinary concentrations of 16 estrogens and 11 polyamines were quantitatively determined by gas chromatography-mass spectrometry and gas chromatography with nitrogen-phosphorus detection. Samples from patients with stages I-IV of breast cancer (35 cases, aged 27-65 years) as well as from age-matched normal female subjects (25 cases, aged 22-61 years) were tested. Also, the ratios of precursor to product metabolite including 16alpha-OH E1 to 2-OH E1, which are linked to estrogen and polyamine biosynthetic pathways, were determined to explore enzyme involvement in breast cancer and to evaluate the potential usefulness of these ratios and concentrations as disease staging markers. It was confirmed that major estrogens and 16a-OH E1 were positively associated with breast cancer and catechol estrogens including 2-OH E1 were inversely associated with breast cancer. The ratios of N1-acSp/Spd and 16alpha-OH E1/2-OH E1 might be a useful dual marker for staging of breast cancer. From the variation of the relative ratios of polyamines, it is suggested that alteration in polyamine oxidase (PAO) activity may play an important role in the development of breast cancer.


Cancer Letters | 1998

Polyamine profiles in the urine of patients with leukemia

Seon Hwa Lee; Ja Won Suh; Bong Chul Chung; Soon Ok Kim

Eleven urinary polyamine levels were determined in controls (32 cases) and 43 patients with varying stages of leukemia including initial, relapse and complete remission, using gas chromatography nitrogen-phosphorus detection. Also, to indirectly evaluate the possible involvement of enzymes, precursor to product concentration ratios were compared between controls and patients with each stage of leukemia. As a result, it is confirmed that the ratio of N1-acSpd/N8-acSpd could be used as a diagnostic marker and the level of N1,N12-diacetylspermine could be used for determining disease stage and as a malignancy marker for leukemia. An altered metabolic pathway related to leukemia is also proposed in which N1,N12-diacetylspermine can be produced directly from spermine and N1,N12-diacetylspermine is a major source of N1-acetylspermidine.


Cancer Letters | 2003

Estrogens in female thyroid cancer: alteration of urinary profiles in pre- and post-operative cases.

Seon Hwa Lee; Kyung Mee Kim; Byung Hwa Jung; Woung Youn Chung; Cheong Soo Park; Bong Chul Chung

To evaluate the potential effect of estrogens in premenopausal female thyroid cancer, the concentrations of 14 estrogens were quantitatively determined in the urine of pre- and post-operative patients with thyroid papillary cancer (18 patients case, 26 approximately 54 years) and normal female subjects (20 cases, 31 approximately 52 years). The highly sensitive gas chromatography-mass spectrometry-selected ion-monitoring method was used for estrogens analysis. And an estrogen-oxidative metabolism and 16alpha-hydroxyestrone to 2-hydroxyestrone (16alpha-OH E1/2-OH E1) which is the two primary and competing site of estrogen-oxidation, were determined. Catechol estrogens, including 2-OH E1, were also increased without significant changes of the other estrogen metabolites in pre-operative patients with thyroid papillary cancer compared with normal subjects. The lowest mean value of 16alpha-OH E1/2-OH E1 was remarked in pre-operative patients, and it was significantly different from the ratio of post-operative cases. As a result, it is suggested that the increase of 2-hydroxylation in estrogen metabolism may have a significant association with female thyroid cancer.


Journal of Chromatography B: Biomedical Sciences and Applications | 1998

Gas chromatographic–mass spectrometric determination of urinary oxoacids using O-(2,3,4,5,6-pentafluorobenzyl)oxime-trimethylsilyl ester derivatization and cation-exchange chromatography

Seon Hwa Lee; Soon Ok Kim; Bong Chul Chung

We introduced a new combined method to isolate, purify and quantify oxoacids in human urine. Preparation of O-(2,3,4,5,6-pentafluorobenzyl) oximes of oxoacids at pH 2 to 3 was followed by cation-exchange column chromatography for removing the biological interferences. The effluent with water was extracted with ethyl acetate and the oxoacids were quantitatively converted into their trimethylsilyl derivatives for detection by gas chromatography-mass spectrometry. Good quality control data were obtained through precision and accuracy tests. Analytical recoveries (53.5-99.8%) were quantitative for a wide variety of oxoacids. This method was used for the measurement of 18 oxoacids in the urine of healthy volunteers.


Clinical Biochemistry | 1999

Androgen imbalance in premenopausal women with benign breast disease and breast cancer.

Seon Hwa Lee; Soon Ok Kim; Sung Won Kwon; Bong Chul Chung

OBJECTIVE The alteration of steroid hormonal status in premenopausal breast disease (benign and malignant) were investigated by comparing the urinary profile of androgens and corticoids. METHODS The urinary concentrations of 25 androgens and corticoids were quantitatively determined by a gas chromatographymass spectrometry system in patients with benign breast disease (35 cases, 20-54 years), breast cancer (34, 27-54), and healthy controls of similar age (25, 22-51). RESULTS In premenopausal patients with breast cancer, a significantly lower rate of excretion of 11-deoxy-17-ketosteroids and their metabolites was found in comparison with normal females. These levels were also inversely associated with benign breast disease. No significant differences were found between the three groups for the concentration of 11-oxy-17-ketosteroids, 17-hydroxy-corticoids and their metabolites. The urinary ratio of adrenal androgen metabolites to cortisol metabolites [(11-DOKS & M)/11-OKS] declined in the order of normal female control (4.04 +/- 0.72; mean +/- SD), breast benign mass (2.29 +/- 0.42) and breast cancer (0.94 +/- 0.27). CONCLUSION Our data suggest that the hormonal imbalance of androgen deficiency and/or corticoid sufficiency is closely associated with the benign and malignant conditions of premenopausal breast disease and the ratio of (11-DOKS & M)/11-OKS may be an effective discriminant factor of these groups.


Clinical Biochemistry | 1998

ALTERED PROFILE OF ENDOGENEOUS STEROIDS IN THE URINE OF PATIENTS WITH PROLACTINOMA

Seon Hwa Lee; Su Youn Nam; Bong Chul Chung

OBJECTIVE The aim of this study was to investigate the possible effect of prolactin on the metabolism of androgens and estrogens in patients with prolactinoma. To accomplish this, prolactin, urinary androgen, and estrogen metabolite levels were determined. In order to indirectly evaluate the possible involvement of enzymes, the concentration ratios of precursor metabolite to product metabolite were also compared with controls. METHODS Urine samples were obtained from 27 female patients with prolactinoma (macro, micro, and idiopathic) and from 31 age-matched normal female subjects. Urinary metabolites of 21 androgens and corticoids and 20 estrogens were analyzed by a gas chromatography-mass spectrometry system. RESULTS In patients with prolactinoma, urinary 17-ketosteroids, and all estrogen metabolite concentrations were elevated. The ratios of delta 5/delta 4-steroids and 5 beta/5 alpha-hydrogensteroids were higher in the patients with prolactinoma than in normal female controls. In addition, no significant differences between patients and controls were observed in the precursor metabolite to product metabolite ratios relating to estrogen metabolism. CONCLUSION Our data suggests that enhanced PRL levels have a direct effect on urinary steroid secretion and metabolism, probably due to lowered activities of 5 alpha-reductase and 3 beta-hydroxysteroid dehydrogenase in the patients with prolactinoma.


Food Additives & Contaminants Part B-surveillance | 2014

Simultaneous analysis of phthalates, adipate and polycyclic aromatic hydrocarbons in edible oils using isotope dilution-gas chromatography–mass spectrometry

Min Seok Oh; Seon Hwa Lee; Myeong Hee Moon; Dong Soo Lee; Hyun Mee Park

A method for simultaneous determination of 12 priority phthalates, adipate and polycyclic aromatic hydrocarbons (PAHs) in edible oils by isotope dilution-gas chromatography–mass spectrometry (ID-GC–MS) was developed for fast, accurate and trace analysis. The extraction and clean-up procedures were optimised, and using stable isotope-labelled internal standards for each analyte, relative standard deviations (RSDs) of 0.92–10.6% and spiked sample recoveries of 80.6–97.8% were obtained. Limits of detection for PAHs were in the range of 0.15–0.77 µg/kg and those for phthalates were in the range of 4.6–10.0 µg/kg. The calibration curves exhibited good linearities with regression coefficients of R2 ≥ 0.99. Twelve edible oils were examined to evaluate the efficiency of this method. Among the 12 analytes, dibutyl phthalates (DBP), diethylhexyl phthalates (DEHP), diethylhexyl adipate (DEHA), benzo[a]anthracene (B[a]A), chrysene (Chry) and benzo[b]fluoranthene (B[b]F) were detected in the range of 1.17–806 µg/kg.

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Bong Chul Chung

Korea Institute of Science and Technology

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Yoon Jung Yang

Korea Institute of Science and Technology

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Ja Won Suh

Korea Institute of Science and Technology

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Soon Ok Kim

Sungshin Women's University

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Jongsei Park

Korea Institute of Science and Technology

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Kyung Mee Kim

Korea Institute of Science and Technology

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Tae-Wook Kim

Korea Institute of Science and Technology

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Byung Hwa Jung

Korea Institute of Science and Technology

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