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Lee KR, Yeom IT. Evaluation of a membrane bioreactor system coupled with sludge pretreatment for aerobic sludge digestion. ENVIRONMENTAL TECHNOLOGY 2007; 28:723-30. [PMID: 17674645 DOI: 10.1080/09593332808618837] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The effects of ozone and alkaline pretreatment of sewage sludge on the performances of membrane-coupled aerobic sludge digestion were investigated. In particular, the effects of sludge pretreatment on the solubilization, sludge biodegradation and the stability of membrane filtration were evaluated. Three sets of reactors were operated under different conditions of sludge treatment; 1) ozone treatment at 0.1 g O3 g(-1) suspended solids (SS) of the influent sludge, 2) alkaline treatment at pH 11.4-12.0, 3) no treatment. Without sludge pretreatment, 27% of suspended solids (SS) reduction was obtained at the hydraulic retention time(HRT) of 5 days. With ozone and alkaline treatment, the average SS reduction increased to 83 and 76%, respectively, at the same HRT. Membrane fouling occurred earliest with the non-treated sludge, followed by the alkali-treated sludge. With ozonated sludge, stable membrane filtration for more than 150 days was possible without chemical cleaning of the membrane. The dynamic viscosity of the mixed liquor in the reactor fed with ozonated sludge was relatively low, indicating the role of ozone treatment in controlling membrane fouling. In conclusion, sludge pretreatment followed by aerobic sludge digestion in a membrane-coupled bioreactor can achieve a very high rate of sludge reduction at a relatively short HRT.
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Kim TY, Ingmar B, Bewilogua K, Oh KH, Lee KR. Wetting behaviours of a-C:H:Si:O film coated nano-scale dual rough surface. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.01.036] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Roy RK, Lee KR. Biomedical applications of diamond-like carbon coatings: A review. J Biomed Mater Res B Appl Biomater 2007; 83:72-84. [PMID: 17285609 DOI: 10.1002/jbm.b.30768] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Owing to its superior tribological and mechanical properties with corrosion resistance, biocompatibility, and hemocompatibility, diamond-like carbon (DLC) has emerged as a promising material for biomedical applications. DLC films with various atomic bond structures and compositions are finding places in orthopedic, cardiovascular, and dental applications. Cells grew on to DLC coating without any cytotoxity and inflammation. DLC coatings in orthopedic applications reduced wear, corrosion, and debris formation. DLC coating also reduced thrombogenicity by minimizing the platelet adhesion and activation. However, some contradictory results (Airoldi et al., Am J Cardiol 2004;93:474-477, Taeger et al., Mat-wiss u Werkstofftech 2003;34:1094-1100) were also reported that no significant improvement was observed in the performance of DLC-coated stainless stent or DLC-coated femoral head. This controversy should be discussed based on the detailed information of the coating such as atomic bond structure, composition, and/or electronic structure. In addition, instability of the DLC coating caused by its high level of residual stress and poor adhesion in aqueous environment should be carefully considered. Further in vitro and in vivo studies are thus required to confirm its use for medical devices.
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McLaughlin JR, Lee KR. The outcome of total hip replacement in obese and non-obese patients at 10- to 18-years. ACTA ACUST UNITED AC 2006; 88:1286-92. [PMID: 17012415 DOI: 10.1302/0301-620x.88b10.17660] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We studied a consecutive series of 285 uncemented total hip replacements in 260 patients using the Taperloc femoral component and the T-Tap acetabular component. The outcome of every hip was determined in both living and deceased patients. A complete clinical and radiological follow-up was obtained for 209 hips in 188 living patients, followed for a mean of 14.5 years (10 to 18.9). They were divided into two groups, obese and non-obese, as determined by their body mass index. There were 100 total hip replacements in 89 patients in the obese cohort (body mass index ≥ 30 kg/m2), and 109 in 99 non-obese (body mass index < 30 kg/m2) patients. A subgroup analysis of 31 patients of normal weight (body mass index 20 kg/m2 to 25 kg/m2) (33 hips) and 26 morbidly obese patients (body mass index ≥ 35 kg/m2) (30 hips) was also carried out. In the obese group five femoral components (5%) were revised and one (1%) was loose by radiological criteria. Femoral cortical osteolysis was seen in eight hips (8%). The acetabular component was revised in 57 hips (57%) and a further 17 (17%) were loose. The mean Harris hip score improved from 52 (30 to 66) pre-operatively to 89 (49 to 100) at final follow-up. Peri-operative complications occurred in seven patients (7%). In the non-obese group six (6%) femoral components were revised and one (1%) was loose. Femoral cortical osteolysis occurred in six hips (6%). The acetabular component was revised in 72 hips (66%) and a further 18 (17%) were loose. The mean Harris hip score increased from 53 (25 to 73) prior to surgery to 89 (53 to 100) at the time of each patient’s final follow-up radiograph. No statistically significant difference was identified between the obese and non-obese patients with regards to clinical and radiological outcome or complications. The subgroup analysis of patients of normal weight and those who were morbidly obese showed no statistically significant difference in the rate of revision of either component. Our findings suggest there is no evidence to support withholding total hip replacement from obese patients with arthritic hips on the grounds that their outcome will be less satisfactory than those who are not obese.
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Lee S, Kong DH, Yun SH, Lee KR, Lee KP, Franzblau SG, Lee EY, Chang CL. Evaluation of a modified antimycobacterial susceptibility test using Middlebrook 7H10 agar containing 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride. J Microbiol Methods 2006; 66:548-51. [PMID: 16563534 DOI: 10.1016/j.mimet.2006.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2005] [Revised: 02/03/2006] [Accepted: 02/09/2006] [Indexed: 11/22/2022]
Abstract
A rapid and accurate antimycobacterial susceptibility test is essential for effective treatment of tuberculosis. The aim of this study was to evaluate a modified method applying 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC) to the Clinical and Laboratory Standards Institute (CLSI) guideline for susceptibility testing of Mycobacterium tuberculosis. A total of 132 clinical isolates of M. tuberculosis, forty-eight isolates showing resistance to one or more of the first-line antituberculosis drugs, and eighty-four fully susceptible isolates were collected from hospitals of a nationwide distribution from June to September 2004. The modified procedure was conducted basically according to the agar-proportion method described in the CLSI Guideline both with STC 50 mug/mL. The amount of growth in each well was recorded and graded at 2nd and 3rd weeks after inoculation. After 3 weeks of incubation, the diagnostic sensitivity and specificity for the detection of drug-resistant strains of STC-containing agar proportion methods were 100%, except ethambutol-low level resistance, of which the diagnostic sensitivity was 93.4%. After two weeks of incubation in STC-containing agar proportion methods, one hundred of the 107 strain-drug combinations have shown drug resistance, indicating the sensitivity of 93.5%. Especially, all 41 isoniazid-resistant strains and 19 of 21 rifampin-resistant strains (90.5%) could be detected after two weeks of incubation. A modification of the agar proportion method using STC resulted in a reliable and more easily interpretable data, and detected most of resistant strains a week earlier than conventional method.
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Ahn DK, Lee KR, Lee HJ, Kim SK, Choi HS, Lim EJ, Park JS. Intracisternal administration of chemokines facilitated formalin-induced behavioral responses in the orofacial area of freely moving rats. Brain Res Bull 2005; 66:50-8. [PMID: 15925144 DOI: 10.1016/j.brainresbull.2005.03.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2005] [Revised: 03/30/2005] [Accepted: 03/31/2005] [Indexed: 11/24/2022]
Abstract
The present study investigated the effects of intracisternal administration of MCP-1, Rantes or IL-8 on pain transmission in the orofacial area. We also investigated mechanisms of hyperalgesic responses produced by intracisternal administration of IL-8. An orofacial formalin test was employed to assess the effects of chemokines on nociceptive processing. For each animal, the number of behavioral responses and the time spent grooming, rubbing and/or scratching the facial region proximal to the formalin injection site was recorded for nine successive 5-min intervals. Intracisternal administration of MCP-1, Rantes or IL-8 significantly increased formalin-induced scratching behavioral responses in the orofacial area. Intracisternal pretreatment with indomethacin, a non-selective cyclooxygenase inhibitor, did not block IL-8-induced hyperalgesia. Pretreatment with 100 microg propranolol, a non-selective beta-adrenergic receptor antagonist and 50 microg atenolol, a selective beta(1)-adrenergic receptor antagonist, inhibited the number of scratches and the duration of scratching produced by 1 ng of IL-8 injected intracisternally. These results indicate that intracisternal administration of chemokines produce a hyperalgesic response with an orofacial inflammatory pain model and that the IL-8-induced hyperalgesia is mediated by central beta(1)-adrenergic receptor.
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Kim SK, Lee JB, Koak JY, Heo SJ, Lee KR, Cho LR, Lee SS. An abutment screw loosening study of a Diamond Like Carbon-coated CP titanium implant. J Oral Rehabil 2005; 32:346-50. [PMID: 15842243 DOI: 10.1111/j.1365-2842.2004.01475.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of this study was to quantify the extent of abutment screw loosening and thus understand the role of frictional and wear factors in abutment screw loosening by using a cyclic loading device to compare Diamond Like Carbon (DLC)-coated and non-coated implants. The properties of DLC films, including hardness, wear resistance, chemical stability, and biocompatibility, are similar to those of real diamond materials. In this study, a 1-mum thick DLC film served to protect and lubricate a layer of commercially-pure titanium affixed to the top of a dental implant (external hexagon-shaped implant). A cyclic loading force was then applied to the top of the prosthetic portion of the implants in order to determine the difference in looseness of the titanium abutment screw between ten DLC-coated implants and ten non-coated implants. The abutment screw loosening tests were performed with 100 N of force at a frequency of 20 Hz. Data indicate that implants with a DLC coating are more resistant to an applied force (P = 0.002) than are those without the coating. We hope these results will be useful for preventing implant abutment screw loosening.
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Yeom IT, Lee KR, Choi YG, Kim HS, Kwon JH, Lee UJ, Lee YH. A pilot study on accelerated sludge degradation by a high-concentration membrane bioreactor coupled with sludge pretreatment. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2005; 52:201-10. [PMID: 16459793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A new sludge treatment process combining a high MLSS membrane bioreactor with sludge pretreatment techniques was studied in pilot-scale experiments. The membrane bioreactor (MBR) was adopted for high efficiency aerobic digestion. The combination of alkaline-ozone treatment of the mixed liquor in the MBR reactor accelerated the biodegradation process by enhancing biodegradability of the sludge. The hydraulic retention time (HRT) of the reactor was set as 3.1 days and the DO level was 1 mg/L on average. After 5 months of operation, the accumulative total solids reduction was more than 70%. Removal efficiency of volatile solids and non-volatile solids were 76% and 54%, respectively. It was found that a considerable portion of the non-volatile solids was dissolved into ions and then flushed out with the effluent. Also, about 41% and 28% of T-N and T-P in the raw sludge were removed although no biological nutrient removal process was adopted. The experiment was run smoothly without significant membrane fouling, even at the relatively high levels of MLSS concentration (11,000-25,000 mg/L). It is concluded that the newly proposed process can significantly increase the sludge reduction efficiency with much shorter retention times.
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Lee HJ, Yoo JY, Kim YG, Han SB, Lee KR. Bioequivalence of a prednisolone tablet administered as a single oral dose in healthy male volunteers. Int J Clin Pharmacol Ther 2004; 42:519-25. [PMID: 15487811 DOI: 10.5414/cpp42519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE A bioequivalence study ofprednisolone as Nisolone (test) tablets versus Delta-Cortef (reference) tablets was conducted. PATIENTS AND METHODS Eighteen healthy male Korean volunteers received both 20 mg formulations of prednisolone in this 2 x 2 crossover study with a 1-week washout period between the doses. Plasma concentrations of prednisolone were monitored over a period of 12 hours after the administration using high-performance liquid chromatography. The AUC (area under the plasma concentration-time curve from time zero to infinity) and AUCt (area under the plasma concentration-time curve from time zero to the last sampling time) were calculated using the trapezoidal rule-extrapolation method. The Cmax (maximum plasma drug concentration) and t(max) (time to reach Cmax) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC, AUCt and Cmax and untransformed t(max). RESULTS The geometric mean of AUCt was 1,786 ng/ml x h (test medication) and 1,787 ng/ml xh (reference medication). A Cmax of 409 ng/ml and 404 ng/ml was achieved for the test and the reference medication, respectively. Point estimates and 90% confidence intervals for AUCt (parametric) and Cmax (parametric) were 0.989 (0.942 approximately 1.039) and 1.013 (0.934 approximately 1.100), respectively. These results satisfy the bioequivalence criteria of the European Committee for Proprietary Medicinal Products and the US Food and Drug Administration Guidelines. The corresponding value of t(max) was -0.221 (-0.415 approximately 0.000). CONCLUSION The 2 medications of prednisolone examined are bioequivalent and, thus, may be prescribed interchangeably.
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Lee CS, Kim TY, Lee KR, Ahn JP, Hyun Yoon K. Nanocomposite ta-C films prepared by the filtered vacuum arc process using nanosized Ni dots on a Si substrate. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.09.081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Kim HK, Song KS, Park YS, Kang YH, Lee YJ, Lee KR, Kim HK, Ryu KW, Bae JM, Kim S. Elevated levels of circulating platelet microparticles, VEGF, IL-6 and RANTES in patients with gastric cancer: possible role of a metastasis predictor. Eur J Cancer 2003; 39:184-91. [PMID: 12509950 DOI: 10.1016/s0959-8049(02)00596-8] [Citation(s) in RCA: 310] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The activation of coagulation, angiogenesis and inflammatory cytokines are considered to be related with tumour growth and metastasis. We investigated the plasma levels of platelet microparticles (PMP), vascular endothelial growth factor (VEGF), IL-6, and the chemokine RANTES in patients with gastric cancer (n=109) and in healthy controls (n=29). The plasma levels of PMP, IL-6 and RANTES were significantly higher in the patients than in the healthy controls, and plasma levels of PMP, VEGF, IL-6 and RANTES were significantly higher in patients with stage IV disease than those in patients with stage I or stage II/III. In terms of predicting distant metastasis, the sensitivities of PMP, VEGF, IL-6 and RANTES were 93.3%, 56.7%, 70.0% and 81.8%, respectively, and the corresponding specificities were 91.1%, 64.6%, 79.7% and 50.0%. Among these parameters, PMP had the highest diagnostic accuracy. Significant correlations were found between PMP, VEGF, IL-6 and RANTES. This study demonstrates that the plasma levels of PMP, VEGF, IL-6 and RANTES were markedly increased in patients with stage IV disease, and that these increased plasma levels of IL-6, RANTES, and especially PMP, might be useful for identifying metastatic gastric patients.
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Kim HK, Song KS, Lee ES, Lee YJ, Park YS, Lee KR, Lee SN. Optimized flow cytometric assay for the measurement of platelet microparticles in plasma: pre-analytic and analytic considerations. Blood Coagul Fibrinolysis 2002; 13:393-7. [PMID: 12138366 DOI: 10.1097/00001721-200207000-00003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Platelet microparticles (PMP) are submicroscopic membrane vesicles released by platelets during activation. Flow cytometry is the most widely used method for quantifying PMP, but the optimization of the technical method has not yet been fully evaluated. This study was designed to assess the pre-analytical variables including blood sampling conditions, and to evaluate the analytical variations including effect of the platelet-specific antibodies and quantitative beads, precision, linearity and accuracy in comparison with beta-thromboglobulin, which is one of the platelet activation markers. Numbers of PMP collected into citrate-theophylline-adenosine-dipyridamole (CTAD) tubes were increased with time, but to a lesser extent than when collected into sodium citrate tubes. The precision of the PMP assay was relatively high. Excellent linear correlation was observed for dilution linearity. Regarding the platelet-specific antibodies used, anti-CD41a-labeled samples resulted in higher PMP levels than those labeled with anti-CD61 and anti-CD42a. There was no significant difference of PMP counts according to the quantitative beads. The PMP assay is well correlated with beta-thromboglobulin levels. Our findings suggest that blood samples for the PMP assay should be collected in a CTAD tube and delayed measurement is not allowed to avoid artefactual platelet activation. The PMP assay can be used successfully as a useful marker of the detection of in vivo platelet activation, provided that pre-analytical and technical points are optimally taken into consideration.
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Yeom IT, Lee KR, Ahn KH, Lee SH. Effects of ozone treatment on the biodegradability of sludge from municipal wastewater treatment plants. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2002; 46:421-425. [PMID: 12361042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effects of ozone pretreatment on the biodegradability of municipal wastewater sludge were determined. Three types of experiments were conducted: anaerobic digestion, aerobic biodegradation, and denitrification using ozone-treated sludge as a carbon source. For 5 days, ozonated sludge at 0.1 gO3/g-SS showed about 2-3 times greater biodegradation compared to the raw sludge in both aerobic and anaerobic conditions. In anaerobic experiments, biodegradation increased with ozone dosage up to 0.2 gO3/g-SS. Further increase of ozone dosage did not improve the biodegradation. In aerobic condition, about 77% of the ozonated sludge at 0.1 gO3/g-SS could be biodegraded after 15 days and is compared with 36% degradation of the untreated sludge. Most of the biodegradation of the ozonated sludge occurred within 5 days while the raw sludge was biodegraded steadily throughout the experimental period. The biodegradation enhancement of ozonated sludge was confirmed in batch denitrification experiments.
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Lee KR, Castrillon DH, Nucci MR. Pathologic findings in eight cases of ovarian serous borderline tumors, three with foci of serous carcinoma, that preceded death or morbidity from invasive carcinoma. Int J Gynecol Pathol 2001; 20:329-34. [PMID: 11603215 DOI: 10.1097/00004347-200110000-00003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We sought to assess the frequency of previously reported adverse histopathologic findings in ovarian serous borderline tumors (SBTs) in cases that preceded a patient's death or caused serious morbidity due to invasive carcinoma. SBTs with foci of invasive carcinoma that occupied a minority of the tumor and were associated with similar outcomes were also studied for potential additional insights. Eight cases were found over a 22-year period. Ten tumors in 5 patients were purely SBT; at initial staging, 1 patient had invasive peritoneal implants; 3 had noninvasive peritoneal implants; 1 was stage I. At last follow-up 3 of the 5 patients had died of carcinoma, 1 was alive with carcinoma, and 1 had no clinical evidence of disease 4 years after a sigmoid colectomy for invasive serous carcinoma of the bowel wall. Four tumors in 3 patients had foci of invasion that were more than microinvasive; at initial staging, all 3 patients had invasive peritoneal implants, and all died of carcinoma. All 14 of the ovarian tumors in the 8 cases had surface involvement by tumor cells, and in 8 tumors in 5 cases they were confined primarily to the ovarian surface. Foci of "micropapillary serous carcinoma" accompanied more obvious areas of infiltrative carcinoma in 2 of the 4 ovarian tumors, the peritoneal implants in 1 of the cases with purely SBTs, and a recurrence in this case and 1 other case. No morphologic finding in the 10 purely SBTs was predictive of subsequent malignant behavior. We conclude that extraovarian invasive serous carcinomas, either following or concurrent with an ovarian SBT, develop from borderline foci that may originate in the ovary, but frequently are likely to have arisen independently in the peritoneum. The carcinomas may be preceded or accompanied by noninvasive-appearing micropapillary foci in the peritoneum in some cases, but micropapillary foci in the ovarian tumors are infrequent and not a necessary antecedent.
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Ren Y, Raitz EN, Lee KR, Pingleton SK, Tawfik O. Pulmonary small lymphocytic lymphoma (mucosa-associated lymphoid tissue type) associated with pulmonary hyalinizing granuloma. Chest 2001; 120:1027-30. [PMID: 11555545 DOI: 10.1378/chest.120.3.1027] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
A case of pulmonary hyalinizing granuloma (PHG) and concomitant low-grade, small lymphocytic lymphoma of the lung is presented. This is the first occurrence of pulmonary lymphoma in patients with PHG ever reported. The infiltrates around a left lower lobe nodule with left pleural effusion and thickening seen on chest CT were histologically proven to be lymphomatous infiltrates of the lung, pleura, and chest wall muscle. We believe that the lymphoma developed around the nodule and spread to the pleura and muscle in our patient. When infiltrates around the nodules, pleural effusion, or adenopathy are developed in a patient with proven PHG, close follow-up, biopsy, or careful cytology should be seriously considered to rule out a developing lymphoma.
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Hur JY, Soh Y, Kim BH, Suk K, Sohn NW, Kim HC, Kwon HC, Lee KR, Kim SY. Neuroprotective and neurotrophic effects of quinic acids from Aster scaber in PC12 cells. Biol Pharm Bull 2001; 24:921-4. [PMID: 11510486 DOI: 10.1248/bpb.24.921] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aster scaber T. (Asteraceae) has been used to treat bruises, snakebite, headache, and dizziness in traditional Chinese medicine. In the present study, the neuroprotective effect of four quinic acid derivatives from A. scaber on amyloid Abeta-induced PC12 cell toxicity was investigated. When cells were treated with quinic acid derivatives prior to Abeta, cell toxicity was significantly diminished. Among quinic acid derivatives, (-)4,5-dicaffeoyl quinic acid (1) gave the highest protection against Abeta-induced cell toxicity. In addition, the neurotrophic effects of compounds were evaluated by microscopically monitoring their potency to induce neurite outgrowth in PC12 cells. Four quinic acid derivatives from A. scaber promoted neurite outgrowth in PC12 cells. Interestingly, a novel quinic acid, (-)3,5-dicaffeoyl-muco-quinic acid (2) was more effective than the other compounds in promoting neurite outgrowth. Unlike nerve growth factor, the withdrawal of quinic acids did not result in any significant decrease in cell viability. The results suggest that quinic acid derivatives from A. scaber might potentially be used as a therapeutic agent in Alzheimer disease.
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Abstract
Repeated column chromatographic separation of the CH2Cl2 extract of Artemisia stolonifera (Asteraceae) led to the isolation of a triterpene (I), a sesquiterpene (II), two aromatic compounds (III and IV) and a benzoquinone (V). Their structures were determined by spectroscopic means to be simiarenol (I), (1S,7S)-1beta-hydroxygermacra-4(15),5,10(14)-triene (II), 3'-methoxy-4'-hydroxy-trans-cinnamaldehyde (III), vanillin (IV) and 2,6-dimethoxy-1,4-benzoquinone (V), respectively. Among these products, compound V showed significant cytotoxicity against five human tumor cell lines in vitro, A549 (non small cell lung adenocarcinoma), SK-OV-3 (ovarian), SK-MEL-2 (skin melanoma), XF498 (CNS) and HCT15 (colon) with ED50 values ranging from 1.33-4.22 microg/ml.
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Jung CM, Kwon HC, Seo JJ, Ohizumi Y, Matsunaga K, Saito S, Lee KR. Two new monoterpene peroxide glycosides from Aster scaber. Chem Pharm Bull (Tokyo) 2001; 49:912-4. [PMID: 11456102 DOI: 10.1248/cpb.49.912] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aerial part of Aster scaber Thunb. (Asteraceae) yielded two new monoterpene peroxide glycosides, (3S)-3-O-(3',4'-diangeloyl-beta-D-glucopyranosyloxy)-7-hydroperoxy-3,7-dimethylocta-1,5-diene (1) and (3S)-3-O-(3',4'-diangeloyl-beta-D-glucopyranosyloxy)-6-hydroperoxy-3,7-dimethylocta-1,7-diene (2), and five known compounds, alpha-spinasterol (3), germacra-4(15),5,10(14)-triene-1-beta-ol (4), 7-methoxy-4(15)-oppositen-1-beta-ol (5), 6alpha-methoxy-4(15)-eudesmane-1beta-ol (6) and alpha-spinasterol 3-O-beta-D-glucopyranoside (7). The structures were established by chemical and spectroscopic methods.
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Kwon HC, Lee KR. An acetylene and a monoterpene glycoside from Adenocaulon himalaicum. PLANTA MEDICA 2001; 67:482-484. [PMID: 11488471 DOI: 10.1055/s-2001-15806] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The methanolic extract of the aerial parts of Adenocaulon himalaicum (Asteraceae) has yielded a new acetylene, 1-O-feruloyl-tetradeca-4E,6E,12E-triene-8,10-diyne (1), a new monoterpene glycoside, 9-hydroxylinaloyl-3-O-(4-O-coumaroyl)-beta-D-glucopyranoside (2), and eight known compounds. Their structures were established by chemical and spectroscopic methods.
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Garrett AP, Lee KR, Colitti CR, Muto MG, Berkowitz RS, Mok SC. k-ras mutation may be an early event in mucinous ovarian tumorigenesis. Int J Gynecol Pathol 2001; 20:244-51. [PMID: 11444200 DOI: 10.1097/00004347-200107000-00007] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We explored the possible pathogenetic pathway for mucinous ovarian tumorigenesis by examining the k-ras mutational patterns in ovarian mucinous tumors (OMTs) with benign, borderline, and invasive epithelium in which the different types of mucinous epithelium are in close proximity. Sixteen patients with ovarian mucinous borderline tumors (OMBTs) and 4 patients with grade 1 ovarian mucinous adenocarcinomas (OMCs) were selected for the presence of a single histologic section which contained a clear "transition" zone from benign mucinous epithelium to borderline mucinous epithelium, and in four cases, to invasive epithelium. A PixCell II Laser Capture Microscope was used to microdissect and retrieve benign, borderline, and invasive epithelium separately from the 20 OMTs. Normal ovarian stroma from the same histologic section in each case was also microdissected and retrieved for use as a control. k-ras mutations were detected in these samples by PCR-SSCP analysis followed by direct PCR cycle sequencing. k-ras mutations were found in 8/16 (50%) of the OMBTs and 2/4 (50%) of the grade 1 OMCs. In 6 of these 10 cases (4 in OMBTs, 2 in grade 1 OMCs), the same k-ras mutation was found in both the benign and borderline (and invasive) regions. In 3 cases in which k-ras mutations were identified, the mutation was found in either the benign or borderline tissue samples alone, and in one case, two distinct mutations were found. No k-ras mutations were identified in the normal ovarian stroma. The presence of a k-ras mutation in adjacent benign and borderline regions of a single OMT may suggest a progression in the development of OMTs from benign to borderline and grade 1 OMCs. k-ras mutations, when they occur, are likely early genetic changes but may not alone be sufficient for malignant transformation of ovarian epithelium.
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Lee HI, Lee JS, Shin EH, Lee WJ, Kim YY, Lee KR. Malaria transmission potential by Anopheles sinensis in the Republic of Korea. THE KOREAN JOURNAL OF PARASITOLOGY 2001; 39:185-92. [PMID: 11441506 PMCID: PMC2721096 DOI: 10.3347/kjp.2001.39.2.185] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To evaluate the factors that determine the transmission level of vivax malaria using vectorial capacity, entomological surveys were conducted from June to August, 2000. From 6 nights of human-bait collection in Paju, the human biting rate (ma) was counted as 87.5 bites/man/night. The parity of Anopheles sinensis from human baiting collections fluctuated from 41% to 71% (average 48.8%) of which the rate gradually increased as time passed on: 35.2% in Jun.; 55.0% in July; 66.2% in Aug. From this proportion of parous, we could estimate the probability of daily survival rate of An. sinensis to be 0.79 assumed with 3 days gonotrophic cycle and the expectancy of infective life through 11 days could be defined as 0.073. Blood meal analysis was performed using ELISA to determine the blood meal source. Only 0.8% of blood meals were from human hosts. We could conclude that An. sinensis is highly zoophilic (cow 61.8%). Malaria is highly unstable (stability index < 0.5) in this area. From these data, vectorial capacity (VC) was determined to be 0.081. In spite of a high human biting rate (ma), malaria transmission potential is very low due to a low human blood index. Therefore, we could conclude that malaria transmission by An. sinensis is resulted by high population density, not by high transmission potential. For this reason, we need more effort to decrease vector population and vector-human contact to eradicate malaria in Korea.
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Abstract
The phytochemical study of the aerial parts of Artemisia japonica ssp. littoricola (Asteraceae) led to the isolation of two acetylenic compounds, (3R)-dehydrofalcarinol (2) and (3R)-dehydrofalcarindiol (6), two sesquiterpenes, 1beta, 6alpha-dihydroxy-4(15)-eudesmene (5) and oplodiol (8), and four phenolic compounds, eugenol (1), vanillin (3), 3'-methoxy-4'-hydroxy-trans-cinnamaldehyde (4) and p-hydroxyacetophenone (7). Their structures were determined by chemical and spectroscopic methods.
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Kim EJ, Jin HK, Kim YK, Lee HY, Lee SY, Lee KR, Zee OP, Han JW, Lee HW. Suppression by a sesquiterpene lactone from Carpesium divaricatum of inducible nitric oxide synthase by inhibiting nuclear factor-kappaB activation. Biochem Pharmacol 2001; 61:903-10. [PMID: 11274976 DOI: 10.1016/s0006-2952(01)00538-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Excessive nitric oxide (NO) produced by inducible NO synthase (iNOS) acts as a causative regulator in various inflammatory disease states. Carpesium divaricatum has been used in Korean traditional herbal medicine for its antipyretic, analgesic, vermifugic, and anti-inflammatory properties. We investigated the molecular mechanism for the suppression of lipopolysaccharide/interferon-gamma (LPS/IFN-gamma)-induced NO production in RAW 264.7 macrophages by the sesquiterpene lactone 2beta,5-epoxy-5,10-dihydroxy-6alpha-angeloyloxy-9beta-isobutyloxy-germacran-8alpha,12-olide (C-1), which has been identified recently as a new compound from C. divaricatum. C-1 decreased NO production in LPS/IFN-gamma-stimulated RAW 264.7 cells in a concentration-dependent manner, with an IC50 of approximately 2.16 microM; however, it had no direct effect on the iNOS activity of fully LPS/IFN-gamma-stimulated RAW 264.7 cells. Furthermore, treatment with C-1 led to a decrease in iNOS protein and mRNA. These effects appear to be due to inhibition of nuclear factor-kappaB (NF-kappaB) activation through a mechanism involving stabilization of the NF-kappaB/inhibitor of the kappaB (I-kappaB) complex, since inhibition of NF-kappaB DNA binding activity by C-1 was accompanied by a parallel reduction of nuclear translocation of subunit p65 of NF-kappaB and I-kappaBalpha degradation. Taken together, the results suggest that the ability of C-1 to inhibit iNOS gene expression may be responsible, in part, for its anti-inflammatory effects.
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Krane JF, Granter SR, Trask CE, Hogan CL, Lee KR. Papanicolaou smear sensitivity for the detection of adenocarcinoma of the cervix: a study of 49 cases. Cancer 2001; 93:8-15. [PMID: 11241260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
BACKGROUND Papanicolaou smear sensitivity for cervical adenocarcinoma (CVCA) is not well established. Also uncertain are the relative contributions to falsely negative diagnoses of sampling, screening, and interpretive errors. METHODS Papanicolaou smears were identified from all patients at our institutions with biopsy-proven cervical adenocarcinoma from 1988-1998. All available negative and unsatisfactory smears were reviewed. RESULTS Of 49 patients with CVCA, 66 smears initially diagnosed as negative and 4 smears initially diagnosed as unsatisfactory from 30 patients were identified. Thirty-two negative smears and 4 unsatisfactory smears from 19 patients were available for review. The retrospective diagnoses in the cases initially called negative were: unsatisfactory in 2, negative in 15, and atypical glandular cells consistent with either adenocarcinoma in situ (AIS) or CVCA in 15. Three of four smears initially called unsatisfactory had neoplastic glandular cells identified retrospectively. The 18 falsely negative or falsely unsatisfactory smears were from 13 patients obtained up to 5 years before biopsy diagnosis. These smears contained neoplastic cells likely to have been mistaken for lower segment endometrial cells (LUS) or endocervical cells with tubal metaplasia (TM) in 11, reactive endocervical cells in 6, and both in 1. In 16 of the 18 smears, the abnormal cells were abundant, although preservation was suboptimal in 6. CONCLUSIONS Sensitivity of a single Papanicolaou smear for CVCA was between 45% and 76% depending on the classification of negative slides that were not available for review, comparable to previously reported sensitivity for AIS. The diagnostic false-negative or false-unsatisfactory rate in reviewed smears was 50% (18 of 36). Diminished sensitivity is due to the under recognition of glandular neoplasia resembling LUS, TM, or reactive endocervical cells. Cancer (Cancer Cytopathol)
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