1.Rapid Diagnosis of Isoniazid Resistance by Detection of Mutations in katG and inhA of Mycobacterium tuberculosis from Korea.
Sang Jae KIM ; Seok Yong KIM ; Ji Youn LEE ; Sang Ryeol RYU ; Gil Han BAI
Journal of the Korean Society for Microbiology 1997;32(5):569-576
29 isoniazid (INH) resistant isolated strains and INH sensitive reference strain (H37Rv) of Mycobacterium tuberculosis were analysed by polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and NciI restriction mapping for the detection of mutations in katG gene and inhA gene. The katG gene was divided into 3 parts (Akat, Bkat, Ckat; each part is about 800 bp) and amplified, inhA gene was amplified as a whole. Each of the amplified 800 bp DNA was digested into small fragments of less than 400 bp with restriction enzymes for the direct PCR-SSCP analysis. Firstly, 10 strains were analysed. All the 10 isolates showed clearly distinct SSCP patterns in Bkat from that of the reference strain, but only two isolates showed distinct SSCP patterns in Akat, and no isolated strain showed any distinct SSCP patterns in Ckat. 10 isolates also showed distinct SSCP patterns in inhA. NciI restriction mapping of Bkat showed mutation in codon 463 in 7 strains among 10 isolated strains. With these results an early detection strategy for the INH resistant M. tuberculosis was applied to the rest of 19 isolated INH resistant strains. Firstly, isolates were screened by Ncsl mapping in Bkat, and 13 strains showed mutations in codon 463. Secondly, the rest of 6 INH resistant isolates were analysed by PCR-SSCP with restriction enzyme digestion (PCR-SSCP-RE) in Bkat, and all the strains showed distinct SSCP patterns from that of the INH sensitive reference strain. This proved our strategy as effective and economic and time saving method in early detection of INH resistant M. tuberculosis.
Codon
;
Diagnosis*
;
Digestion
;
DNA
;
Isoniazid*
;
Korea*
;
Mycobacterium tuberculosis*
;
Mycobacterium*
;
Polymorphism, Single-Stranded Conformational
;
Restriction Mapping
;
Tuberculosis
2.Calcification of Chronic Subdural Hematoma in a Child: Case Report.
Youn Seok RYU ; Kyung Uk CHO ; Soon Kie KIM ; Myong Sun MOON
Journal of Korean Neurosurgical Society 1986;15(2):287-292
Intracranial calcification is relatively common, but calcification of chronic subdural hematoma is rare condition. Nevertheless, already in 1884 Von Rokitansky had described a calcified chronic subdural hematoma found at autopsy. Subsequently Lewis(1889), Elsner(1896), and O'sullivan(1925) mentioned calcification of intracranial hematoma. In 1930, Goldham reported the first case treated by operation. A 15-year-old Korean male was admitted to this hospital because of a episode of generalized epileptic seizure, one day before admission. Past history was unknown about head injury and his past birth condition. Patient has complained weakness of right upper and lower extremely since his infant. Neurological examination revealed the left hemiparesis, but others were normal. Skull X-ray films showed dense conglomerated calcific density with surrounding rim like lucency in left fronto-parietal region. Left carotid angiogram revealed no abnormalities except hypoplasia of left hemisphere. Brain computed tomogram demonstrated hyperdense subdural mass surrounding decreased parenchymal density in left fronto-parietal region. A craniectomy was performed for removal of the calcified mass. A oval concaved bony hard mass was found in subdural space. The calcified bony hard mass was adherent with the surface of cortex by loose sonnective tissue. We removed the bony hard mass completely. The postoperative course was very satisfactory and seizure has not been appeared after discharge. Microscopic findings demonstrated ossification and fibrosis, consisting with old hematoma which showed up a calcification of chronic subdural hematoma.
Adolescent
;
Autopsy
;
Brain
;
Child*
;
Craniocerebral Trauma
;
Epilepsy
;
Fibrosis
;
Hematoma
;
Hematoma, Subdural, Chronic*
;
Humans
;
Infant
;
Male
;
Neurologic Examination
;
Paresis
;
Parturition
;
Seizures
;
Skull
;
Subdural Space
;
X-Ray Film
3.Meningioma of the Frontal and Ethmoidal Sinus: Case Report.
Youn Seok RYU ; Kyung Uk CHO ; Soon Kie KIM ; Myong Sun MOON
Journal of Korean Neurosurgical Society 1986;15(2):271-278
The meningioma constitutes 12 to 16 percent of all intracranial tumors. Generally, meningiomas arise from intracranial arachnoid villi and located intracranially. Extension of an intracranial meningioma onto the frontal and ethmoidal sinus occurs occassionally, but primary meningiomas of the frontal and ethmoidal sinus are extremely rare. The authors experienced a case of cystic, meningotheliomatous meningioma containing lamellated calcification involving of the lest frontal and ethmoidal sinus, which presented with protrusion of frontal bone and exophthalmos. In addition to our case, other types of extracranial meningioma are discussed with review of literature.
Arachnoid
;
Exophthalmos
;
Frontal Bone
;
Meningioma*
4.Current Progress of Next Generation Battery of Toxicology-Cellular and Molecular Toxicology, and Toxicogenomics.
Jae Chun RYU ; Seok joo YOON ; Jong Eun LEE ; Youn Jung KIM
Genomics & Informatics 2004;2(4):153-162
No abstract available.
Toxicogenetics*
;
Toxicology*
5.Tobacco Smoking Could Accentuate Epithelial-Mesenchymal Transition and Th2-Type Response in Patients With Chronic Rhinosinusitis With Nasal Polyps
Ki-Il LEE ; Younghwan HAN ; Jae-Sung RYU ; Seung Min IN ; Jong-Yeup KIM ; Joong Su PARK ; Jong-Seok KIM ; Juhye KIM ; Jubin YOUN ; Seok-Rae PARK
Immune Network 2022;22(4):e35-
Tobacco smoking (TS) has been known as one of the most potent risk factors for airway inflammatory diseases. However, there has been a paucity of information regarding the immunologic alteration mediated by TS in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). To identify the effect of TS, we harvested human tissue samples (never smoker: n=41, current smoker: n=22, quitter: n=23) and analyzed the expression of epithelialderived cytokines (EDCs) such as IL-25, IL-33, and thymic stromal lymphopoietin. The expressions of Th2 cytokines and total serum IgE showed a type-2 inflammatory alteration by TS. In addition, the epithelial marker E-cadherin and epithelial-mesenchymal transition (EMT)-associated markers (N-cadherin, α-SMA, and vimentin) were evaluated. Histological analysis showed that EDC expressions were upregulated in the current smoker group and downregulated in the quitter group. These expression patterns were consistent with mRNA and protein expression levels. We also found that the local Th2 cytokine expression and IgE class switching, as well as serum IgE levels, were elevated in the current smoker group and showed normal levels in the quitter group. Furthermore, the expressions of E-cadherin decreased while those of N-cadherin, α-SMA, and vimentin increased in the current smoker group compared those in the never smoker group. Taken together, these results indicate that TS contributes to the deterioration of pathogenesis by releasing local EDCs and Th2 cytokines, resulting in EMT in patients with CRSwNP. We verified that alterations of immunological response by TS in sinonasal epithelium can play a vital role in leading to CRSwNP.
6.Endoxifen Concentration Is Associated with Recurrence-Free Survival in Hormone-Sensitive Breast Cancer Patients
Beomki LEE ; Seok Jin NAM ; Seok Won KIM ; Jonghan YU ; Byung-Joo CHAE ; Se Kyung LEE ; Jai Min RYU ; Jeong Eon LEE ; Soo-Youn LEE
Cancer Research and Treatment 2025;57(1):140-149
Purpose:
The metabolism of tamoxifen is influenced by various cytochrome p450 enzymes, including CYP2D6 and CYP2C19, leading to variations in the levels of endoxifen, even with the same tamoxifen dose. However, the clinical significance of endoxifen for the prognosis of breast cancer patients remains controversial. This study aimed to elucidate the relevance of endoxifen level to recurrence-free survival censored with tamoxifen discontinuation (RFSt), representing the RFS for tamoxifen itself, of breast cancer patients and determine a suitable cutoff for prognostication.
Materials and Methods:
The study included 478 breast cancer patients. Tamoxifen and its metabolites, including endoxifen, were measured using liquid chromatography-tandem mass spectrometry. An optimal cutoff was determined with maximally selected rank statistics. Survival analysis and Cox regression were conducted based on this cutoff.
Results:
An endoxifen level of 21.00 ng/mL was the optimal cutoff for prognostication. Survival analysis revealed a statistically significant difference in RFSt between the low endoxifen group (≤ 21.00 ng/mL) and the high endoxifen group (> 21.00 ng/mL) (log-rank test, p=0.032). The 10-year probability of RFSt was 83.2% (95% confidence interval [CI], 77.0 to 89.9) and 88.3% (95% CI, 83.3 to 93.5) in the low and high endoxifen groups, respectively. Multivariable Cox proportional hazards regression indicated endoxifen concentration as a significant factor associated with prognosis.
Conclusion
Endoxifen could serve as a marker for appropriate tamoxifen treatment with a cutoff of 21.00 ng/mL. Based on this cutoff, therapeutic drug monitoring would benefit patients displaying suboptimal endoxifen concentrations.
7.Endoxifen Concentration Is Associated with Recurrence-Free Survival in Hormone-Sensitive Breast Cancer Patients
Beomki LEE ; Seok Jin NAM ; Seok Won KIM ; Jonghan YU ; Byung-Joo CHAE ; Se Kyung LEE ; Jai Min RYU ; Jeong Eon LEE ; Soo-Youn LEE
Cancer Research and Treatment 2025;57(1):140-149
Purpose:
The metabolism of tamoxifen is influenced by various cytochrome p450 enzymes, including CYP2D6 and CYP2C19, leading to variations in the levels of endoxifen, even with the same tamoxifen dose. However, the clinical significance of endoxifen for the prognosis of breast cancer patients remains controversial. This study aimed to elucidate the relevance of endoxifen level to recurrence-free survival censored with tamoxifen discontinuation (RFSt), representing the RFS for tamoxifen itself, of breast cancer patients and determine a suitable cutoff for prognostication.
Materials and Methods:
The study included 478 breast cancer patients. Tamoxifen and its metabolites, including endoxifen, were measured using liquid chromatography-tandem mass spectrometry. An optimal cutoff was determined with maximally selected rank statistics. Survival analysis and Cox regression were conducted based on this cutoff.
Results:
An endoxifen level of 21.00 ng/mL was the optimal cutoff for prognostication. Survival analysis revealed a statistically significant difference in RFSt between the low endoxifen group (≤ 21.00 ng/mL) and the high endoxifen group (> 21.00 ng/mL) (log-rank test, p=0.032). The 10-year probability of RFSt was 83.2% (95% confidence interval [CI], 77.0 to 89.9) and 88.3% (95% CI, 83.3 to 93.5) in the low and high endoxifen groups, respectively. Multivariable Cox proportional hazards regression indicated endoxifen concentration as a significant factor associated with prognosis.
Conclusion
Endoxifen could serve as a marker for appropriate tamoxifen treatment with a cutoff of 21.00 ng/mL. Based on this cutoff, therapeutic drug monitoring would benefit patients displaying suboptimal endoxifen concentrations.
8.Endoxifen Concentration Is Associated with Recurrence-Free Survival in Hormone-Sensitive Breast Cancer Patients
Beomki LEE ; Seok Jin NAM ; Seok Won KIM ; Jonghan YU ; Byung-Joo CHAE ; Se Kyung LEE ; Jai Min RYU ; Jeong Eon LEE ; Soo-Youn LEE
Cancer Research and Treatment 2025;57(1):140-149
Purpose:
The metabolism of tamoxifen is influenced by various cytochrome p450 enzymes, including CYP2D6 and CYP2C19, leading to variations in the levels of endoxifen, even with the same tamoxifen dose. However, the clinical significance of endoxifen for the prognosis of breast cancer patients remains controversial. This study aimed to elucidate the relevance of endoxifen level to recurrence-free survival censored with tamoxifen discontinuation (RFSt), representing the RFS for tamoxifen itself, of breast cancer patients and determine a suitable cutoff for prognostication.
Materials and Methods:
The study included 478 breast cancer patients. Tamoxifen and its metabolites, including endoxifen, were measured using liquid chromatography-tandem mass spectrometry. An optimal cutoff was determined with maximally selected rank statistics. Survival analysis and Cox regression were conducted based on this cutoff.
Results:
An endoxifen level of 21.00 ng/mL was the optimal cutoff for prognostication. Survival analysis revealed a statistically significant difference in RFSt between the low endoxifen group (≤ 21.00 ng/mL) and the high endoxifen group (> 21.00 ng/mL) (log-rank test, p=0.032). The 10-year probability of RFSt was 83.2% (95% confidence interval [CI], 77.0 to 89.9) and 88.3% (95% CI, 83.3 to 93.5) in the low and high endoxifen groups, respectively. Multivariable Cox proportional hazards regression indicated endoxifen concentration as a significant factor associated with prognosis.
Conclusion
Endoxifen could serve as a marker for appropriate tamoxifen treatment with a cutoff of 21.00 ng/mL. Based on this cutoff, therapeutic drug monitoring would benefit patients displaying suboptimal endoxifen concentrations.
9.Coronary Artery Size in Korean: Normal Value and its Determinants.
Eung Ju KIM ; Ji Youn YOO ; Won Seok CHEON ; Sung Woo HAN ; Young Jin CHOI ; Kyu Hyung RYU ; Chong Yun RHIM
Korean Circulation Journal 2005;35(2):115-122
BACKGROUND AND OBJECTIVES: Although the size of the coronary artery is known to be closely related to the outcome of coronary artery bypass grafting and percutaneous coronary intervention, its normal value and determinants have not been examined in Koreans. SUBJECTS AND METHODS: One hundred and twenty seven normal coronary arteriograms were carefully selected from 3,412 studied consecutively. Of these, 53 women and 23 men, with no abnormalities in their cardiac function and not using nitrates, were studied. The lumen diameter was measured at 10 segments in the epicardial coronary arteries. RESULTS: For men, the mean lumen diameter of the proximal left anterior descending and left circumflex coronary arteries were 3.88+/-0.39 and 3.45+/-0.47 mm, respectively, and were not affected by the anatomic dominance. However, the left main and proximal right coronary arteries varied between 4.44+/-0.49 and 5.18+/-0.32 mm (p<0.05) and 3.29+/-0.60 and 4.05+/-0.42 mm (p<0.05), respectively, by the anatomic dominance. Women had a smaller mean coronary artery size than men [for diameter, -7% (p<0.01);for cross-sectional area, -13% (p<0.01)], and the left ventricular (LV) mass was significantly associated with coronary artery diameter (p<0.05). From a multiple linear regression analysis, gender was an only independent predictor of the coronary artery size (p<0.05). CONCLUSION: We revealed normal coronary artery dimensions in Koreans. Although, body size, hypertension, use of calcium channel blockers, anatomic dominance and age had no effect on the size of the coronary artery, but the LV mass and gender were shown to have an effect. The multivariate regression analysis showed gender was an only independent predictor of the coronary artery size.
Asian Continental Ancestry Group
;
Body Size
;
Calcium Channel Blockers
;
Coronary Artery Bypass
;
Coronary Vessels*
;
Female
;
Humans
;
Hypertension
;
Linear Models
;
Male
;
Nitrates
;
Percutaneous Coronary Intervention
;
Reference Values*
10.The Clinicopathological Features and Postoperative Complications of Completion Thyroidectomy for Recurrent Papillary Thyroid Carcinoma.
Chang Woo KIM ; So Hee LEE ; Haeng Rang RYU ; Kang Young RHEE ; Sang Wook KANG ; Jong Joo JUNG ; Kee Hyun NAM ; Hang Seok CHANG ; Woong Youn CHUNG ; Cheong Soo PARK
Korean Journal of Endocrine Surgery 2009;9(3):161-166
PURPOSE: A completion thyroidectomy after less than total thyroidectomy is needed for the treatment of recurrent papillary thyroid carcinoma (PTC). The aim of this study is to evaluate the clinicopathological features and the postoperative complications of completion thyroidectomy for patients with recurrent PTC. METHODS: A total 94 PTC patients who had undergone prior less than total thyroidectomy underwent completion thyroidectomy for recurrence from March 1986 to June 2009. We retrospectively analyzed the clinicopathological features and postoperative complications. RESULTS: At the initial operation, the patients' mean age was 38.2 years old. Central node metastasis was found in 37 cases and extrathyroidal invasion was found in 12 cases. The mean interval time between the initial operation to the completion thyroidectomy was 76.6 months. Fifty six patients underwent completion thyroidectomy only and 38 underwent a completion thyroidectomy combined with a modified radical neck dissection. In the combined group, central neck node metastasis and extrathyroidal invasion at the time of the initial operation were significantly more frequent than those in the completion thyroidectomy only group. The postoperative complications were 14 cases of transient hypocalcemia and 8 cases of permanent hypocalcemia and there were no significant differences between the two groups. CONCLUSION: When performing completion thyroidectomy, it is important to check the lateral neck nodes for metastasis when central neck node metastasis or extrathyroidal invasion were present at the initial operation, and this can be done safely without severe complications even though it is combined with modified radical neck dissection.
Humans
;
Hypocalcemia
;
Neck
;
Neck Dissection
;
Neoplasm Metastasis
;
Postoperative Complications*
;
Recurrence
;
Retrospective Studies
;
Thyroid Gland*
;
Thyroid Neoplasms*
;
Thyroidectomy*