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Koh JS, Cho KJ, Kim HS, Kim JC. Twelve-month medication persistence in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia. Int J Clin Pract 2014; 68:197-202. [PMID: 24372906 DOI: 10.1111/ijcp.12241] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 06/30/2013] [Indexed: 12/22/2022] Open
Abstract
AIMS This study aimed to assess patients' baseline characteristics and provider factors influencing the continuation of medication for 12 months in patients who were newly diagnosed with benign prostatic hyperplasia (BPH). METHODS This study was conducted in patients with newly diagnosed lower urinary tract symptoms (LUTS)/BPH (age ≥ 40) who received either one or a combination of the two pharmacological classes of drugs (alpha-blockers or 5-alpha-reductase inhibitors) from January 2008 to January 2010. Patient demographics and clinical data were assessed from the electronic patient records and telephone surveys. Persistence was defined as continuation of all BPH medications prescribed at the start of the first treatment. Logistic regression analysis was used to evaluate the association between 12-month persistence and patient or provider factors. RESULTS Of the 789 newly diagnosed LUTS/BPH patients, 670 (84.9%) were included in the study. Twelve-month persistence for LUTS/BPH medication was 36.6%. Independent predictors of 12-month medication persistence included larger prostate volume, higher prostate specific antigen, having an adequate income and a good patient-doctor relationship. Important reasons for discontinuation were resolved symptoms (31.1%), no improvement in symptoms (23.7%) and adverse events (20.0%). CONCLUSIONS About two-thirds of newly diagnosed LUTS/BPH patients discontinued medications within 1 year of starting treatment. We found several potential patient and provider factors associated with persistence, which could be exploited to increase continuation of treatment in future clinical settings.
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Lee SY, Baek JH, Shin MK, Koh JS. The quantitative analysis of spreadability, coverage, and adhesion effect after application of the base make-up product. Skin Res Technol 2013; 20:341-6. [DOI: 10.1111/srt.12124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2013] [Indexed: 12/01/2022]
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An SM, Ham H, Choi EJ, Shin MK, An SS, Kim HO, Koh JS. Primary irritation index and safety zone of cosmetics: retrospective analysis of skin patch tests in 7440 Korean women during 12 years. Int J Cosmet Sci 2013; 36:62-7. [PMID: 24117720 DOI: 10.1111/ics.12095] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 09/15/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Cosmetics are products used over long periods by the public, and their safety is very important. Several types of human tests are used widely for the evaluation of cosmetics including single patch tests, in-use tests, human repeated insult patch test (HRIPT). However, there is no clear and well-defined published objective and standardized criteria for primary skin irritation in regard to the large variety of cosmetic products. METHODS This study analysed human patch tests conducted from May 2001 to December 2012 with 4606 materials of prototype or finished cosmetic products on 7440 normal Korean women aged 18-60 years. The tested products were patched under occlusion for 24 or 48 h, and skin tolerance was assessed twice at 30 min and 24 h after patch removal using a 5-step scale according to the CTFA guidelines. RESULTS Human patch tests for cosmetics were performed of 4606 cases, and 30-33 subjects participated in each case. The response in each case was calculated based on total subject number, skin reaction intensity and the number of respondents. The calculated response was standardized using the z-score, and a safety zone was provided in terms of human primary irritation in accordance with the human skin reaction evaluation criteria and usage or formula of cosmetics. CONCLUSIONS This study established the safety criteria for irritation in the cosmetics field.
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Park YH, Jeong YH, Koh JS, Kwak CH, Hwang JY. Pharmacodynamic effect of cilostazol versus clopidogrel in stented patients during proton pump inhibitor co-administration: the result of the ACCEL-PARAZOL study. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.p4912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Jeong YH, Park YH, Koh JS, Ch KWAK, Hwang JY, Gurbel PA, Tantry US. Pharmacodynamic effect of adjunctive cilostazol vs. high-dos clopidogrel in acute coronary syndrome patients according to the CYP2C19 genotype (ACCEL-GENOTYPE) study. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.p4914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Park YH, Jeong YH, Koh JS, Kwak CH, Hwang JY. Effect of rabeprazole versus famotidine on platelet inhibition in patients with normal clopidogrel responsiveness: result of the ACCEL-PROTECT randomized study. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.p4910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Jeong YH, Koh JS, Park YH, Hwang JY, Kwak CH. Influence of CYP2C19 *2 and *3 loss-of-function alleles on phenotyping and clopidogrel pharmacodynamics. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht310.p4908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lee SH, Koh JS, Ryu CW, Lee CY, Lee SJ. Successful endosaccular coiling after a balloon occlusion test of the caudal channel of a double origin of the posterior inferior cerebellar artery originating from the aneurysm neck. Interv Neuroradiol 2011; 17:183-7. [PMID: 21696656 DOI: 10.1177/159101991101700207] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Accepted: 03/19/2011] [Indexed: 11/17/2022] Open
Abstract
Therapeutic strategies for unruptured aneurysms in elective procedures must be carefully planned with respect to safety. We describe the case of a patient who presented with an unruptured aneurysm associated with a double origin of the posterior inferior cerebellar artery (DOPICA), a rare variant of aberrant origin. A three-dimensional rotational angiogram clearly showed that the aneurysm incorporated the origin of the DOPICA caudal channel, which was more dominant than the cranial one. The aneurysm was completely obliterated using detachable coils after a balloon occlusion test (BOT) of the caudal channel was conducted to confirm the tolerance of the patient following sudden interruption of the more prominent flow coming from the caudal channel of the DOPICA. This report affirms the need to suspect anomalies associated with a DOPICA that predispose to intracranial aneurysms and highlights the potential role of a BOT in pretreatment hemodynamic evaluations of unusual aneurysms accompanying a particular developmental anomaly.
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Shim YS, Pae CU, Kim SW, Kim HW, Kim JC, Koh JS. Effects of repeated dosing with Udenafil (Zydena) on cognition, somatization and erection in patients with erectile dysfunction: a pilot study. Int J Impot Res 2011; 23:109-14. [PMID: 21544084 DOI: 10.1038/ijir.2011.13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The PDE5 inhibitors have recently been found to have cognitive-enhancing effects in animal models. To investigate the efficacy of repeated dosing with a PDE5 inhibitor on cognitive function and somatization in patients with erectile dysfunction, 27 patients with erectile dysfunction received udenafil (100 mg) at 3-day intervals for 2 months. The international index of erectile function-5 (IIEF-5), a cognitive battery (the Korean version of mini-mental state examination (K-MMSE), the frontal assessment battery (K-FAB), the Seoul verbal learning test) and a physical health questionnaire-15 (PHQ-15) were performed at baseline and at 2 months, following the administration of udenafil. The patients were divided on the basis of their IIEF-5 score into responders (change>7) and non-responders. The mean IIEF-5 score was significantly increased after treatment (7.92 ± 3.83 to 16.33 ± 4.75, P<0.001). The scores of K-MMSE (27.03 ± 1.58 to 28.07 ± 1.57, P=0.001), K-FAB (13.65 ± 1.96 to 15.41 ± 1.85, P<0.001) and PHQ-15 (18.92 ± 4.96 to 17.63 ± 4.75, P=0.003) were significantly improved after treatment. In addition, the responders (n=16) had more improved cognitive function (r=0.603, P=0.001) and somatization (r=-0.402, P=0.038) than non-responders (n=11). Repeated dosing with a PDE5 inhibitor seems to improve cognitive function and somatization, as well as erectile function in patients with erectile dysfunction.
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Baek JH, Lee MY, Koh JS. Relationship between clinical features of facial dry skin and biophysical parameters in Asians. Int J Cosmet Sci 2011; 33:222-7. [PMID: 21338373 DOI: 10.1111/j.1468-2494.2010.00608.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
There have been few reports classifying the biophysical characteristics of Korean women with healthy skin. Consequently, the aim of this study was to find the most useful parameters for categorizing skin types based on a clinical assessment. One hundred and three female volunteers, aged 20-59, participated in this study. We conducted a self-evaluation questionnaire, a clinical assessment of the facial skin, and non-invasive measurements on the cheek under controlled environmental conditions. The questionnaire survey indicated that 72% of respondents had dry skin. However, results of the clinical assessment focusing on skin roughness and scaling of the cheek showed that 6 subjects had very dry skin (6%), 29 had dry skin (28%) and 68 had normal skin with sufficient moisture (66%). We analysed the correlation between the clinical assessment and biophysical parameters. As a result, we obtained six biophysical parameters that had relatively higher correlations with clinical assessment than other parameters. Our study provided general information about the physiological characteristics of normal skin in Korean women and suggested useful parameters for characterizing dry skin.
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Na II, Park JY, Kim KM, Cheon GJ, Choe DH, Koh JS, Baek HJ, Lee JC. Significance of smoking history and FDG uptake for pathological N2 staging in clinical N2-negative non-small-cell lung cancer. Ann Oncol 2011; 22:2068-2072. [PMID: 21257671 DOI: 10.1093/annonc/mdq693] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND This study was conducted to evaluate whether smoking history and the standardized uptake value (SUV) of 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) uptake are associated with unexpected pathological N2 status (pN2) in non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS We analyzed the data of 220 patients who underwent surgical resection with clinical N2-negative status on computed tomography (CT) and positron emission tomography (PET)-CT. The maximum SUV of primary tumor was chosen for logistic analysis. RESULTS Seventy-two patients (33%) had never smoked. The SUV ranged from 1.0 to 29.0 (median 9.1). In univariate analysis, adenocarcinomas (P = 0.019), female gender (P = 0.010), N1 on CT (P = 0.025), and N1 PET-CT (P = 0.001) were associated with a high probability of pN2. The proportion of pN2 in never smokers was higher than in ever smokers (26% versus 10% respectively; P = 0.002). The SUV remained on a multivariate logistic model (odds ratio 1.1; 95% confidence interval 1.0-1.2; P = 0.010) and it had a better predictive value in never smokers than in ever smokers (P = 0.017). CONCLUSIONS This study indicates an association between smoking history and pN2 in clinically negative N2 NSCLC. The different roles of FDG uptake were also suggested based on smoking history.
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Seo YK, Kim SJ, Boo YC, Baek JH, Lee SH, Koh JS. Effects of p-coumaric acid on erythema and pigmentation of human skin exposed to ultraviolet radiation. Clin Exp Dermatol 2010; 36:260-6. [DOI: 10.1111/j.1365-2230.2010.03983.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lee KH, Chang PC, Lie DT, Koh JS, Ong KL. An unusual case of knee locking. Singapore Med J 2010; 51:e140-e142. [PMID: 20848054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Knee locking is an incapacitating condition that requires urgent orthopaedic intervention. The most common cause is meniscal injury, followed by torn anterior cruciate ligament, osteochondral loose bodies and foreign bodies in the joint space. This report describes a patient who had an unusual case of left knee locking. After clinical examination and radiological investigations, the provisional diagnosis was a lateral meniscal tear, which was not visible on magnetic resonance imaging. Diagnostic arthroscopy of the left knee revealed a 1-cm yellowish lump on the medial meniscus, and the histology revealed pigmented villonodular synovitis. The menisci and cruciate ligaments were intact.
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Kim BM, Suh SH, Park SI, Shin YS, Chung EC, Lee MH, Kim EJ, Koh JS, Kang HS, Roh HG, Won YS, Chung PW, Kim YB, Suh BC. Management and clinical outcome of acute basilar artery dissection. AJNR Am J Neuroradiol 2008; 29:1937-41. [PMID: 18687744 DOI: 10.3174/ajnr.a1243] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND PURPOSE There have been inconsistencies on the prognosis and controversies as to the proper management of acute basilar artery dissection. The aim of this study was to evaluate acute basilar artery dissection and its outcome after management. MATERIALS AND METHODS A total of 21 patients (mean age, 53 years; range, 24-78 years) with acute basilar artery dissection were identified between January 2001 and October 2007. Clinical presentation, management, and outcomes were retrospectively evaluated. RESULTS The patients presented with subarachnoid hemorrhage (n = 10), brain stem ischemia (n = 10), or stem compression sign (n = 1). Ruptured basilar artery dissections were treated by stent placement with coiling (n = 4), single stent placement (n = 3), or conservatively (n = 3). Of the patients treated with endovascular technique, 6 had favorable outcome (modified Rankin scale [mRS], 0-2) and the remaining patient, who was treated by single stent placement, died from rebleeding. All 3 conservatively managed patients experienced rebleeding, of whom 2 died and the other was moderately disabled. Unruptured basilar artery dissections were treated conservatively (n = 7) or by stent placement (n = 4). Of the patients with unruptured basilar artery dissection, 9 had favorable outcome and the remaining 2 patients, both of whom were conservatively managed, had poor outcome because of infarct progression. The group with the ruptured basilar artery dissection revealed a higher mortality rate than the group with the unruptured dissection (30% vs 0%). The group treated with endovascular means revealed more favorable outcome than the group that was treated with conservative measures (90.9% vs 50%). CONCLUSION The ruptured basilar artery dissections were at high risk for rebleeding, resulting in a grave outcome. Stent placement with or without coiling may be considered to prevent rebleeding in ruptured basilar dissections and judiciously considered in unruptured dissections with signs of progressive brain stem ischemia.
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Koh JS, Lee SS, Baek HJ, Kim YI. No association of high-risk human papillomavirus with esophageal squamous cell carcinomas among Koreans, as determined by polymerase chain reaction. Dis Esophagus 2008; 21:114-7. [PMID: 18269645 DOI: 10.1111/j.1442-2050.2007.00726.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The incidence of esophageal squamous cell carcinoma varies greatly with race and geographic location. It has been suggested that human papillomavirus (HPV) is involved in the pathogenesis of esophageal cancers, and that the incidence of esophageal cancers associated with HPV depends on the geographic location of the patient population. In studies performed on tumor specimens collected from areas with a low incidence of esophageal squamous cell carcinomas, HPV infection was detected in only a small percentage of tumors, whereas studies performed on specimens obtained from areas with a high incidence of esophageal squamous cell carcinomas provided strong evidence that HPV plays a significant role in esophageal carcinogenesis. To elucidate the putative role of HPV infection in the etiology of esophageal cancer in Korea, a total of 129 formalin-fixed, paraffin-embedded tumor specimens, eight fresh tumor tissues and 40 normal esophageal tissues were screened for HPV infection by polymerase chain reaction using consensus primers for HPV types 16, 18, 31, 33, 35, 52b and 58 and type 16-specific primers. SiHa cell line, formalin-fixed, paraffin-embedded cervical squamous cell carcinoma specimens were used as positive controls for HPV infection. Fragments of human beta-globin gene, which served as the internal controls, were successfully amplified from 102 of the 129 cancer specimens and from all the normal and fresh cancer tissues, while consensus and type 16-specific primers failed to detect HPV DNA sequences in any of the esophageal samples. The DNA extracted from the SiHa cell line and uterine cervical cancers were positive when both the consensus and type-specific primers were used. The results of this study suggest that HPV is not associated with esophageal carcinogenesis in Korea.
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Lee HK, Seo YK, Baek JH, Koh JS. Comparison between ultrasonography (Dermascan C version 3) and transparency profilometry (Skin Visiometer SV600). Skin Res Technol 2007; 14:8-12. [DOI: 10.1111/j.1600-0846.2007.00257.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lim YJ, Lee CY, Koh JS, Kim TS, Kim GK, Rhee BA. Seizure control of Gamma Knife radiosurgery for non-hemorrhagic arteriovenous malformations. ACTA NEUROCHIRURGICA. SUPPLEMENT 2006; 99:97-101. [PMID: 17370773 DOI: 10.1007/978-3-211-35205-2_19] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
OBJECTIVES Although radiosurgery has been found to be a safe and effective alternative treatment, seizure outcome of arteriovenous malformation (AVM) radiosurgery has not been documented in detail. We report the effect of Gamma Knife radiosurgery (GKRS) on seizures associated with AVMs and discuss the various factors that influence the prognosis. MATERIAL AND METHODS Between 1992 and 2004, 246 patients were treated with GKRS for AVMs at Kyung-Hee medical center. Forty five (17.0%) patients have non-hemorrhagic AVMs and presenting symptom was seizure. Two patients of all were excluded from this study due to loss of follow-up after radiosurgery. In this study, retrospective analysis of clinical characteristics, radiologic findings, radiosurgical seizure outcome were performed. RESULTS There were 32 male and 11 female with age ranging from 10 to 74 years (mean 35 years). Type of seizure included: general tonic clonic (n = 28); focal motor or sensory (n = 7); partial complex (n = 8). The location of AVM was temporal (n = 18); frontal (n = 9); deep seated (n = 7): parietal (n = 5); occipital (n = 4). Follow-up period was from 8 months to 12 years (mean 46 months). Mean volume was 6.2 cc (2.7-20), mean marginal and maximal dosage was 19.5 (17-26) and 36.6 Gy (13-50). During follow-up after radiosurgical treatment, 23 (53.5%) of 43 patients were seizure-free, 10 (23.3%) had significant improvement, were unchanged in 8 (18.6%) and aggravated in 2 (4.6%) patients. In 33 patients, follow-up angiography or MRI was performed. Complete obliteration was achieved in 16 (49.0%) patients, partial obliteration in 13 (39.0%). Four were unchanged (12.0%). Of 33 patients with follow-up performed, 26 were followed for over 2 years. Eleven (84.6%) of 13 patients with complete obliteration were seizure-free (p < 0.005). Four (36.3%) of 13 with partial obliteration and unchanged remained seizure-free. Fifteen patients had experienced intractable seizure before radiosurgery. After radiosurgery, seizures disappeared in 8 (53%) patients. Seizure frequently decreased in 5 (33%) and 2 patients (14%) were unchanged but none was aggravated. Five (71%) of 7 patients with complete obliteration were seizure-free and 2 (40%) of 5 patients with partial obliteration were seizure-free. CONCLUSION Up to now, controversy about resective surgery or radiosurgery as treatment of seizure related to AVMs still remains. In this study, we experienced that Gamma Knife radiosurgery is commonly performed to treat AVMs and can improve symptomatic seizure associated with AVMs. To clarify the mechanism of seizure control in AVMs radiosurgery is difficult, but it seems to be closely related to hemodynamic effects after radiosurgery.
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Koh JS, Trent J, Chen L, El-Naggar A, Hunt K, Pollock R, Zhang W. Gastrointestinal stromal tumors: overview of pathologic features, molecular biology, and therapy with imatinib mesylate. Histol Histopathol 2004; 19:565-74. [PMID: 15024716 DOI: 10.14670/hh-19.565] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. These tumors develop at any site but are most commonly reported in the stomach. They originate from the neoplastic transformation of the intestinal pacemaker cell, the interstitial cell of Cajal. GISTs strongly express the receptor tyrosine kinase KIT and have mutations in the KIT gene, most frequently in exon 11 encoding the intracellular juxtamembranous region. Expression of KIT is seen in almost all GISTs, regardless of the site of origin, histologic appearance, or biologic behavior, and is therefore regarded as one of the key diagnostic markers. Distinction from smooth muscle tumors, such as leiomyosarcomas, and other mesenchymal tumors is very important because of prognostic differences and therapeutic strategies. Predicting the biologic behavior of GISTs is often difficult by conventional pathologic examination; tumor size and mitotic rate are the most important prognostic indicators. The prognostic significance of KIT mutations is controversial and thus far has not been clearly linked with biologic behavior. KIT mutations are associated with tumor development, and cytogenetic aberrations are associated with tumor progression. The pathogenesis of GISTs involves a gain-of-function mutation in the KIT proto-oncogene, leading to ligand-independent constitutive activation of the KIT receptor. KIT-wild-type GISTs have shown mutually exclusive platelet-derived growth factor receptor (PDGFR) mutation and activation. The use of imatinib mesylate (also known as Gleevec or STI-571) has greatly increased the therapeutic efficacy for this otherwise chemotherapy-resistant tumor. GISTs with very low levels of KIT expression may respond to imatinib mesylate therapy if the receptors are activated by specific mechanisms. KIT-activating mutations fall into two groups: the regulatory type and the enzymatic site type. The regulatory type of mutation is conserved at the imatinib binding site, whereas the enzymatic site mutation has a structurally changed drug-binding site, resulting in drug resistance. Resistance to the drug is the major cause of treatment failure in cancer therapy, emphasizing the need for researchers to understand KIT signaling pathways so as to identify new therapeutic targets. This review summarizes the pathologic features of GISTs, recent advances in understanding their molecular and biologic features, and therapy with imatinib mesylate.
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Lee H, Lee J, Lee S, Shin Y, Jung W, Kim JH, Park K, Kim K, Cho HS, Ro S, Lee S, Jeong SW, Choi T, Chung HH, Koh JS. A novel class of highly potent, selective, and non-peptidic inhibitor of Ras farnesyltransferase (FTase). Bioorg Med Chem Lett 2001; 11:3069-72. [PMID: 11714612 DOI: 10.1016/s0960-894x(01)00624-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Design, synthesis and structure-activity relationship of a class of aryl pyrroles as farnesyltransferase inhibitors are described. In vitro and in vivo evaluation of a panel of these inhibitors led to identification of 2 (LB42908) as a highly potent (IC(50)=0.9 nM against H-Ras and 2.4 nM against K-Ras) antitumor agent that is currently undergoing preclinical studies.
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Lee H, Lee J, Shin Y, Jung W, Kim JH, Park K, Ro S, Chung HH, Koh JS. 3-Aryl-4-aryloyl-1-(1H-imidazol-5-yl)methylpyrrole, a novel class of farnesyltransferase inhibitors. Bioorg Med Chem Lett 2001; 11:2963-5. [PMID: 11677136 DOI: 10.1016/s0960-894x(01)00593-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Design, synthesis and structure-activity relationship of a class of 3-aryl-4-aryloyl-1-(1H-imidazol-5-yl)methylpyrroles as farnesyltransferase inhibitors are described. Compound 7 inhibits farnesyltransferase with an IC(50) value of 4.6 nM.
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Lieberthal W, Fuhro R, Andry CC, Rennke H, Abernathy VE, Koh JS, Valeri R, Levine JS. Rapamycin impairs recovery from acute renal failure: role of cell-cycle arrest and apoptosis of tubular cells. Am J Physiol Renal Physiol 2001; 281:F693-706. [PMID: 11553517 DOI: 10.1152/ajprenal.2001.281.4.f693] [Citation(s) in RCA: 223] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The immunosuppressive effect of rapamycin is mediated by inhibition of interleukin-2-stimulated T cell proliferation. We report for the first time that rapamycin also inhibits growth factor-induced proliferation of cultured mouse proximal tubular (MPT; IC(50) ~1 ng/ml) cells and promotes apoptosis of these cells by impairing the survival effects of the same growth factors. On the basis of these in vitro data, we tested the hypothesis that rapamycin would impair recovery of renal function after ischemic acute renal failure induced in vivo by renal artery occlusion (RAO). Rats given daily injections of rapamycin or vehicle were subjected to RAO or sham surgery. Rapamycin had no effect on the glomerular filtration rate (GFR) of sham-operated animals. In rats subjected to RAO, GFR fell to comparable levels 1 day later in vehicle- and rapamycin-treated rats (0.25 +/- 0.08 and 0.12 +/- 0.05 ml. min(-1). 300 g(-1), respectively) (P = not significant). In vehicle-treated rats subjected to RAO, GFR increased to 0.61 +/- 0.08 ml. min(-1). 300 g(-1) on day 3 (P < 0.02 vs. day 1) and then rose further to 0.99 +/- 0.09 ml. min(-1). 300 g(-1) on day 4 (P < 0.02 vs. day 3). By contrast, GFR did not improve in rapamycin-treated rats subjected to RAO over the same time period. Rapamycin also increased apoptosis of tubular cells while markedly reducing their proliferative response after RAO. Furthermore, rapamycin inhibited activation of 70-kDa S6 protein kinase (p70(S6k)) in cultured MPT cells as well as in the renal tissue of rats subjected to RAO. We conclude that rapamycin severely impairs the recovery of renal function after ischemia-reperfusion injury. This effect appears to be due to the combined effects of increased tubular cell loss (via apoptosis) and profound inhibition of the regenerative response of tubular cells. These effects are likely mediated by inhibition of p70(S6k).
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Koh JS, Cheng CW, Foo KT. Spectrum of prostate cancer in the Singapore General Hospital (1980 to 1985). ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2001; 30:513-5. [PMID: 11603136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
INTRODUCTION Serum prostate specific antigen (PSA) testing has contributed to a dramatic rise in the incidence of prostate cancer diagnosed in the last decade in the West as well as in Singapore. Now prostate cancer is ranked as the sixth commonest cancer among men in Singapore. To form the basis for comparisons and to assess the trends and impact of these changes, we analysed the presentation, disease characteristics and outcome of treatment of patients with prostate cancer diagnosed in the pre-PSA era at the Singapore General Hospital (SGH). MATERIALS AND METHODS Of the 149 patients (1980 to 1985) registered in the database, 134 (90%) records with full follow-up data were available for the analysis. All patients were diagnosed and managed at SGH. Follow-up and death data were collected through clinic visit, phone interviews of the patients, relatives, family physicians and the death registry. Survival analysis was carried out using the Kaplan-Meier product limit method. RESULTS The mean age at diagnosis was 69.8 years. There were no significant changes with reference to each year during 1980 to 1985 and the mean number of diagnoses per year was 22.3. Of the 134 patients, 86% had either retention of urine or severe lower urinary tract symptoms and 14% had metastatic disease at presentation. Most histological diagnosis was made during prostatectomy; wherein 82% was found with transurethral resection of the prostate (TURP) and 12% in open prostatectomy, respectively. Pathological analysis during diagnosis revealed that 72.4% patients had metastatic disease. Of which, 57.5% had high-grade (Gleason > 7) tumours. Among these, 82% underwent TURP to relieve urinary obstruction, while 26.1% received local irradiation to the prostate. Majority had hormone therapy shortly after diagnosis in the form of orchidectomy or oral diethylstilbestrol (76.1%). The median crude survival (26 months) was minimal for metastatic patients. CONCLUSION The spectrum of prostate cancer in the pre-PSA era was characterised by high stages of high-grade disease, with very limited opportunity for successful treatment and hence survival.
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Koh JS, Chung JH, Kweon MS, Lee SS, Lee SY, Lee JH. Fine needle aspiration cytology of late-stage callus in stress fracture. A case report. Acta Cytol 2001; 45:445-8. [PMID: 11393083 DOI: 10.1159/000327647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Fine needle aspiration cytology (FNAC) is effective in the diagnosis of bone lesions when combined with careful radiologic and clinical evaluation. The cytologic features of callus have not been described before in the English-language literature. CASE An 18-year-old female presented with a pain in the right lower leg that had been present for two months. Clinical and radiologic findings suggested either stress fracture or periosteal osteosarcoma. The aspiration specimen showed individually scattered, oval cells with moderate amounts of pale pink cytoplasm. The cells contained a single eccentrically located nucleus with evenly distributed, fine chromatin. Osteoclastic giant cells were scattered in the smears. A cytologic diagnosis of benign bone-forming lesion, compatible with callus in fracture, was made. The diagnosis of late-stage callus was confirmed by subsequent histologic examination. CONCLUSION Typical cases of stress fracture do not need histologic examination, but some cases may be confused with benign and malignant bone tumors. The typical and unique cytologic features of late-stage callus combined with clinical and radiologic findings may prevent the use of more invasive diagnostic procedures and can be a choice for management.
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Koh JS, Chung JH, Lee SY, Lee JH. Chondrosarcoma of the proximal femur with myxoid degeneration mistaken for chondromyxoid fibroma in a young adult. A case report. Acta Cytol 2001; 45:254-8. [PMID: 11284314 DOI: 10.1159/000327285] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Fine needle aspiration cytology (FNAC) is effective in the diagnosis of bone tumors when combined with careful radiologic and clinical evaluation. However, cases where clinical or radiologic findings are atypical or unusual may lead to an erroneous diagnosis. CASE A 19-year-old male presented with a pain in the left hip area that had been slowly progressive over a 10-month period. Clinical and radiologic findings suggested either giant cell tumor or chondroblastoma. The smeared aspiration specimen showed loosely cohesive, oval to round cells with moderate amounts of pale pink cytoplasm admixed with pinkish-blue, chondromyxoid material. The individual cells contained a single nucleus with evenly distributed, fine chromatin. A few osteoclastic giant cells were scattered in the smears. A cytologic diagnosis of myxoid lesion with a few giant cells, suspicious for chondromyxoid fibroma, was made. The diagnosis of chondrosarcoma was made by subsequent histologic examination. CONCLUSION Absence of the usual clinicoradiologic features of chondrosarcoma combined with an unusual cytologic presentation in this case led to a misdiagnosis. In most centers, FNAC has achieved undisputed status as a diagnostic tool, and cytologic diagnosis often forms the basis of the therapeutic protocol. However, at some sites FNAC diagnosis is more problematic. Awareness of the limitations and pitfalls of FNAC is just as important as knowledge of the scope of FNAC in bone tumors. Tumors with chondromyxoid features provide particular difficulties.
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Koh JS, Wang Z, Levine JS. Cytokine dysregulation induced by apoptotic cells is a shared characteristic of murine lupus. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:4190-201. [PMID: 11035051 DOI: 10.4049/jimmunol.165.8.4190] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Of the multiple murine models of autoimmunity, the three most closely resembling human systemic lupus erythematosus (SLE) are the MRL/lpr, New Zealand Black/White F(1), and male BXSB. Although these strains share many disease characteristics, no common cellular defect has previously been found in prediseased mice from all these strains. We show in this study that macrophages from prediseased mice of all three SLE-prone strains, as well as macrophages from mice whose genomes contribute to the development of SLE (MRL/+, New Zealand White, New Zealand Black, female BXSB, and LG/J), have an identical and profound defect in cytokine expression that is triggered by apoptotic cells. Strikingly, none of 13 nonautoimmune strains tested exhibited this defect. Given that apoptotic Ags have been increasingly recognized as the target of autoantibodies, a defect in cytokine expression that is triggered by apoptotic cells has broad potential to upset the balance between tolerance and immunity.
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MESH Headings
- Animals
- Apoptosis/immunology
- Cells, Cultured
- Culture Media, Conditioned
- Culture Media, Serum-Free
- Cytokines/biosynthesis
- Cytokines/deficiency
- Cytokines/metabolism
- Disease Models, Animal
- Disease Susceptibility
- Female
- Fetal Blood/immunology
- Interleukin-1/biosynthesis
- Interleukin-1/deficiency
- Interleukin-1/metabolism
- Lipids/immunology
- Lupus Erythematosus, Systemic/immunology
- Lupus Erythematosus, Systemic/metabolism
- Lupus Erythematosus, Systemic/pathology
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- Macrophages, Peritoneal/pathology
- Male
- Mice
- Mice, Inbred AKR
- Mice, Inbred BALB C
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Inbred CBA
- Mice, Inbred MRL lpr
- Mice, Inbred NZB
- Signal Transduction/immunology
- Species Specificity
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