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Moon MW, Park SY, Kim HK, Yum DY, Kwak HS, Oh TK, Lee JK. Cloning and expression of the ccpA gene encoding catabolite control protein from Thermoactinomyces sp. E79. Biosci Biotechnol Biochem 2000; 64:2254-8. [PMID: 11129608 DOI: 10.1271/bbb.64.2254] [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: 11/08/2022]
Abstract
The gene ccpA encoding the catabolite control protein A (CcpA) of Thermoactinomyces sp. E79 has been cloned and characterized. Nucleotide sequence analysis of the CcpA clone showed that the cloned fragment contained the full structural gene for a protein of 346 amino acids. The predicted amino acid sequence shows similarity to the transcriptional regulators of the Lacl-GalR family; a highly conserved helix-turn-helix motif, which might bind to DNA, was identified through comparison with regulator proteins in this family. The highest sequence identity was obtained when it was compared with the CcpA of Bacillus subtilis (60%) or Bacillus megaterium (60%). The expression of ccpA in Thermoactinomyces sp. E79 was dependent on glucose, which is contrast to the cases of B. subtilis, B. megaterium and S. xylosus. The complementation experiment with the B. megaterium ccpA mutant indicated that the cloned gene was a ccpA.
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Yasui K, Kada K, Hojo M, Lee JK, Kamiya K, Toyama J, Opthof T, Kodama I. Cell-to-cell interaction prevents cell death in cultured neonatal rat ventricular myocytes. Cardiovasc Res 2000; 48:68-76. [PMID: 11033109 DOI: 10.1016/s0008-6363(00)00145-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVES Loss of cardiac cells and the anatomical or functional remodeling of intercellular coupling occur under several pathological conditions. We have assessed the significance of intercellular coupling for cell death. METHODS AND RESULTS Ventricular cells obtained from 1 day old Wistar rats were cultured. Apoptosis was detected by nick-end labeling. Cells were plated at low and high cell density (3x10(4)/ml and 12x10(4)/ml, respectively). Cultured myocytes died spontaneously by apoptosis in a time dependent manner. The increase of the apoptotic cell population in a culture with high cell density on day 4 (1+/-1.2%, n=4) was significantly lower than that in a culture with low cell density (20+/-5.5%, n=4). The progression of apoptosis in the culture of low cell density was prevented in part after application of the medium extract from the culture of high cell density; the apoptotic cell population on day 6 decreased from 57+/-8.0% (n=4) to 36+/-3.8% (n=4). Treatment of the cultured myocytes at high cell density with antisense oligonucleotide for connexin43 (Cx43) for 24 h on day 2 resulted in a significant decrease in Cx43 expression as judged by Western blot, dye transfer and immunocytochemistry using mouse monoclonal antibody for Cx43. In association with the down-regulation of Cx43, the progress of apoptosis was accelerated; the apoptotic cell population on day 5 in the antisense-treated cultures (27+/-5.7%, n=4) was significantly higher than the sense-treated cultures (5+/-1.1%, n=4). The effect of Cx43 antisense treatment to promote apoptosis was not reversed by application of high cell-density culture medium. CONCLUSIONS These findings suggest that cell-cell communication through gap junction formation and some humoral factors play important roles in the survival of cultured myocytes.
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Sun SS, Tsai SC, Hsu NY, Shih CS, Lee JK, Kao CH. Preoperative and postoperative lymphoscintigraphy using Tc-99m sulfur colloid in the repair of a lymphatic leak in a patient with traumatic chylothorax. Clin Nucl Med 2000; 25:840-1. [PMID: 11043737 DOI: 10.1097/00003072-200010000-00027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Boger DL, Lee JK. Development of a solution-phase synthesis of minor groove binding bis-intercalators based on triostin A suitable for combinatorial synthesis. J Org Chem 2000; 65:5996-6000. [PMID: 10987932 DOI: 10.1021/jo000382r] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The development of a solution phase synthesis of azatriostin A (2) suitable for the preparation of combinatorial libraries enlisting only liquid-liquid acid/base extractions for the isolation and purification of all intermediates and the final product is disclosed.
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Kim JS, Jang JH, Lee JW, Kang SO, Kim KS, Lee JK. Identification of cis site involved in nickel-responsive transcriptional repression of sodF gene coding for Fe- and Zn-containing superoxide dismutase of Streptomyces griseus. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1493:200-7. [PMID: 10978523 DOI: 10.1016/s0167-4781(00)00178-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A sodF gene coding for iron- and zinc-containing superoxide dismutase (FeZnSOD) of Streptomyces griseus was cloned and sequenced. A 5' end of 0.8-kb sodF transcript was mapped at the 57 nucleotides upstream from an ATG initiation codon. Employing expressions of sodF::xylE fusions in trans in Streptomyces lividans, nickel-responsive transcriptional repression was found to be relieved if mutations were introduced into an operator sequence of inverted-repeat, TTGCAN(7)TGCAA, which traverses the 5' end (+1, G) of the sodF mRNA. Nickel-dependent interaction between cell extracts and sodF regulatory DNA, monitored through gel-mobility shift assay, was abolished when the operator was mutated. Recombinant sodF operon having operator mutations showed protein level and enzyme activity, which were no longer repressed by nickel, suggesting that nickel-responsive repression of FeZnSOD is regulated mainly at the level of transcription through the operator.
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Choi YH, Lee JK, Lee CH, Cho SH. cDNA cloning and expression of an aminoalcoholphosphotransferase isoform in Chinese cabbage. PLANT & CELL PHYSIOLOGY 2000; 41:1080-4. [PMID: 11100782 DOI: 10.1093/pcp/pcd030] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Aminoalcoholphosphotransferase (AAPT) catalyzes the synthesis of phosphatidylcholine and phosphatidylethanolamine from diacylglycerol plus a CDP-aminoalcohol such as CDP-choline or CDP-ethanolamine. Previously we reported the cloning of a cDNA encoding this enzyme from Chinese cabbage roots, and suggested the presence of possible isoforms [Min et al. (1997) J. Plant Biol. 40: 234]. We now report the cDNA cloning and expression analysis of a second AAPT from Chinese cabbage. This AAPT cDNA, AAPT2, contains an open reading frame of 1,170 bp coding for a protein of 389 amino acids. It shares 95% identity and 96% similarity with Chinese cabbage AAPT1 at the deduced amino acid level. The results from reverse transcriptase-PCR indicate that expression of AAPT2 is regulated temporally and up-regulated by low temperature.
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Lee JK, Kim GH, Kim JS, Kim KK, Lee MC, Yoo HW. Identification of four novel mutations in five unrelated Korean families with Fabry disease. Clin Genet 2000; 58:228-33. [PMID: 11076046 DOI: 10.1034/j.1399-0004.2000.580311.x] [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: 11/23/2022]
Abstract
Fabry disease is a X-linked recessively inherited metabolic disorder, which results from the deficient activity of the lysosomal hydrolase alpha-galactosidase A leading to the systemic deposition of glycosphingolipids with terminal alpha-galactosyl moieties. Single-strand conformation polymorphism (SSCP) analysis was performed, followed by DNA sequencing of PCR amplified exons of the human alpha-galactosidase A gene in 5 unrelated Korean patients with classic Fabry disease. Five different mutations were identified; two nonsense mutations (Y86X and R342X), one missense mutation (D266N), and two small deletions (296del2 and 802del4). Except for R342X mutation, four were novel mutations (Y86X, D266N, 296del2, 802del4). A T to G transversion at nucleotide position 5157 in exon 2 caused a tyrosine-to-stop substitution at codon 86. A G to A transition at position 10287 in exon 5 substituted an asparagine for an aspartate at codon 266. Mutation 296del2 in exon 2 resulted in a frame shift with a stop signal at the 22th codon downstream from the mutation, whereas mutation 802del4 resulted in a stop codon at the site of 4 bp deletion. In addition, the 802del4 was found to be a de novo mutation. This is the first report on mutation analysis of the human alpha-galactosidase A gene in Korean patients with Fabry disease.
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Sun SS, Hsieh JF, Tsai SC, Ho YJ, Lee JK, Kao CH. Detection of esophageal carcinoma using single photon emission computed tomography with technetium-99m tetrofosmin. Anticancer Res 2000; 20:3641-5. [PMID: 11268432] [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
Technetium-99m tetrofosmin (Tc-TF) a thallium-201 (Tl-201) and technetium-99m methoxy-isobutyl-isonitrile (Tc-MIBI) competitor, being used as a new radiopharmaceuticalfor myocardial imaging was assessed to understand its value in detecting esophageal carcinoma (Eso-Ca). Forty patients with Eso-Ca underwent Tc-TF single photon emission computed tomography (SPECT) of the chest. Meanwhile 15 controls also accepted Tc-TF SPECT of the chest for comparison. Among the 40 patients Tc-TF chest SPFCT detected Eso-Ca in 33 (82.5%) but not in 7 (17.5%). In contrast all 15 normal controls (100.0%) had negative Tc-TF chest SPECT Detection sensitivities were higher for tumors located in the middle portion of the esophagus for epidermoid ca and for tumors with poor differentiation when compared with tumors in the upper or lower portion for adenocarcinoma and tumors with moderate differentiation. However, the differences were not significant (p values < 0.05). Significantly higher detection sensitivity was found for tumors of larger size than for tumors of smaller size (p value < 0.05). Our results suggest that Tc-TF chest SPECT is a helpful test for detecting Eso-Ca especially larger tumors.
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311
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Lee JK, Sara TT. Experience in snuffbox arteriovenous fistulae for hemodialysis. THE MEDICAL JOURNAL OF MALAYSIA 2000; 55 Suppl C:35-8. [PMID: 11200042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Sixty-five patients with "Snuffbox" arteriovenous fistulae for hemodialysis were reviewed. The procedure was performed under local anaesthesia as an outpatient procedure. It was done as a "standby" procedure for 41.5% of patients with Chronic Ambulatory Peritoneal Dialysis. 58.5% of patients had the procedure done for primary hemodialysis. Patency was assessed as presence of an engorged vein and presence of thrill. This was assessed routinely at 4 to 6 weeks after the procedure. Patency rate was noted to be 83%. The commonest complication was thrombosis of the arteriovenous anastomosis. Some patients required repeated procedure at a more proximal site. Further study to determine the blood flow rate provided by the anastomosis, and comparison with other anatomical sites is necessary.
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Hong YJ, Lee JK, Lee GH, Hong SI. Influence of glutathione S-transferase M1 and T1 genotypes on larynx cancer risk among Korean smokers. Clin Chem Lab Med 2000; 38:917-9. [PMID: 11097350 DOI: 10.1515/cclm.2000.134] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Glutathione S-transferase (GST) isoenzymes are involved in the detoxification of major carcinogens present in tobacco smoke. It is thus conceivable that deficiency in GST activity due to homozygous deletions of the GSTM1 and GSTT1 genes (the null genotypes) may modulate susceptibility to smoking-induced cancers. The influence of the GSTM1 and GSTT1 null genotypes on larynx cancer risk among the Korean population were evaluated using peripheral blood DNA from 82 larynx cancer patients and 63 healthy controls, all of whom were male current smokers. Increased larynx cancer risk was related to the GSTM1 null genotype (odds ratio (OR)=3.53, 95% confidence interval (CI)=1.27-9.83). The OR associated with the GSTT1 null genotype was also increased, but did not reach statistical significance (OR=1.83, 95% CI=0.70-4.79). Individuals lacking both the GSTM1 and GSTT1 genes were at a significantly higher risk for larynx cancer than individuals with both genes present (OR=4.04, 95% CI=1.33-12.30). These data confirm that the GSTM1 null genotype is an important risk modifier for larynx cancer among Korean smokers and combined GSTM1 and GSTT1 null genotypes could be a useful predictor of genetic susceptibility to larynx cancer.
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Lee JK, Choi HY, Lee SW, Baek SY, Kim HY. Usefulness of T1-weighted image with fast inversion recovery technique in intracranial lesions: comparison with T1-weighted spin echo image. Clin Imaging 2000; 24:263-9. [PMID: 11331152 DOI: 10.1016/s0899-7071(00)00229-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
To evaluate the usefulness of T1-weighted images using the fast inversion recovery (T1FIR) technique as compared with routine T1-weighted spin echo (T1SE) images in various intracranial lesions. Routine spin echo and T1FIR images were performed in 15 consecutive patients with 18 lesions, cerebral infarction in five, astrocytoma in four, vascular lesion in three, encephalomalacia and hemorrhage in each two, arachnoid cyst and meningioma in each one. T1FIR images were performed with 1.5-T Signa [repetition time (TR)/echo time (TE)/inversion time (TI) was 2000/34/800 in 14, 4000/34/1200 in four lesions] and qualitatively compared with the T1SE images in signal intensity, lesion detectability, determination of lesion extent and conspicuity, contrast between lesion and background. Additionally, gray-to-white matter and cerebrospinal fluid (CSF)-to-white matter contrast were evaluated. The signal intensity of the lesions was similar on both T1FIR and T1SE images in all cases. The lesion detectability was similar on both sequences in 15 lesions, and the determination of the lesion extent was definitely higher in 16 lesions on the T1FIR images. Lesion conspicuity was superior in 11, similar in 5, and inferior in 2 patients on the T1FIR images. And also, contrast of lesion-to-background, gray-to-white matter, and CSF-to-white matter was superior on the T1FIR images. The T1FIR technique improved the determination of lesion extent and lesion conspicuity and was qualitatively superior for image contrast as compared with T1SE, but it takes more time than T1SE. The clinical application of T1FIR images depends on whether the superior aspect of the T1FIR images outweighs the disadvantage of the longer time required for this technique.
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Jung S, Lee JK, Kim SH, Kim JH, Kang SS, Lee JH. Parietal sinus pericranii: case report and technical note. SURGICAL NEUROLOGY 2000; 54:270-2; discussion 273. [PMID: 11118576 DOI: 10.1016/s0090-3019(00)00225-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Sinus pericranii is a rare vascular anomaly that is defined as a group of abnormal communications between the extracranial and intracranial venous systems, usually involving the superior sagittal sinus. Different surgical techniques have been used to manage this anomaly. Surgical technique and radiologic findings are discussed. CLINICAL PRESENTATION A case of parietal sinus pericranii is presented that was developed spontaneously. This 33-year-old woman presented with a soft fluctuant mass in the right parietal region adjacent to the midline. She complained of headache and dizziness. The preoperative radiologic findings of simple skull X-ray, computed tomography, bone scan, and direct venogram are presented. The lesion was removed completely and then multiple small vascular channels through the underlying skull were obliterated by air-powered diamond drilling. The presence of vascular endothelium in the pathologic specimen suggested a congenital origin. CONCLUSION We think this method is very easy and useful for managing the multiple small fenestrations of the sinus pericranii without recurrence.
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315
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Lee JK, Kim DB, Kim JI, Kim PY. In vitro cytotoxicity tests on cultured human skin fibroblasts to predict skin irritation potential of surfactants. Toxicol In Vitro 2000; 14:345-9. [PMID: 10906441 DOI: 10.1016/s0887-2333(00)00028-x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cultured human skin cells are a potentially useful model for skin irritancy testing. We have investigated the use of human skin fibroblasts for in vitro screening for skin toxicity. To assess the cytotoxic effects of surfactants, cell viability was measured by the NRU (neutral red uptake) assay and AB (Alamar blue) assay as in vitro methods. The skin irritation potential of surfactants by human skin patch test was assessed as in vivo methods. The close relationship was found between AB assay with human skin fibroblasts and human patch test (r=0.867). There was a relatively good agreement between the NRU and in vivo patch test (r=0.648). These results suggest that AB and NRU assay using cultured human fibroblast could be predictable methods for the irritancy of various surfactants in human.
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Lee JK, Hong YJ, Han CJ, Hwang DY, Hong SI. Clinical usefulness of serum and plasma vascular endothelial growth factor in cancer patients: which is the optimal specimen? Int J Oncol 2000. [PMID: 10853032 DOI: 10.3892/ijo.17.1.149] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is secreted by various human cancer cells and plays a key role in cancer angiogenesis and metastasis. Recently, evidence of VEGF storage in blood cells including platelets has been reported. The serum VEGF levels were reported to increase during clotting as a result of its release from platelets, and plasma sample instead of serum was recommended for measuring the circulating VEGF more accurately. However, platelets have been implicated in tumor metastasis since circulating tumor cells forming aggregates with platelets were observed. The purpose of this study was to clarify which is an optimal specimen to measure VEGF in cancer patients, serum or plasma. We measured serum and plasma VEGF levels and platelet counts in 173 cancer patients and 42 healthy people, and found that serum VEGF levels were significantly higher than matched plasma VEGF and the VEGF difference (serum VEGF - plasma VEGF) correlated with platelet counts (r=0.624, p<0.05) in both cancer patients and healthy controls. We selected cancer patients with normal platelet counts (130-400x103/microl, Plt-normal cancer group). Interestingly, serum VEGF levels were higher in Plt-normal cancer group than in healthy controls. The theoretical platelet-derived VEGF in serum, calculated based on actual blood platelet counts (pg per 106 platelets), was also significantly higher in Plt-normal cancer group than in normal controls. It is, therefore, suggested that, although the serum VEGF levels are affected by blood platelets, platelet-derived VEGF also reflect biology of cancer cells, and that serum would be the more useful specimen for measurement of circulating VEGF in cancer patients for prognosis.
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Park SY, Kim HK, Yoo SK, Oh TK, Lee JK. Characterization of glk, a gene coding for glucose kinase of Corynebacterium glutamicum. FEMS Microbiol Lett 2000; 188:209-15. [PMID: 10913707 DOI: 10.1111/j.1574-6968.2000.tb09195.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The glk gene from Corynebacterium glutamicum was isolated by complementation using Escherichia coli ZSC113 (ptsG ptsM glk). We sequenced a total of 3072 bp containing the 969-bp open reading frame encoding glucose kinase (Glk). The glk gene has a deduced molecular mass of 34.2 kDa and contains a typical ATP binding site. Comparison with protein sequences revealed homologies to Glk from Streptomyces coelicolor (43%) and Bacillus megaterium (35%). The glk gene in C. glutamicum was inactivated on the chromosome via single crossover homologous recombination and the resulting glk mutant was characterized. Interestingly, the C. glutamicum glk mutant showed poor growth on rich medium such as LB medium or brain heart infusion medium in the presence or absence of glucose, fructose, maltose or sucrose as the sole carbon source. Growth yield was reduced significantly when maltose was used as the sole carbon source using minimal medium. The growth defect of glk mutant on rich medium was complemented by a plasmid-encoded glk gene. A chromosomal glk-lacZ fusion was constructed and used to monitor glk expression, and it was found that glk was expressed constitutively under all tested conditions with different carbon sources.
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Sun SS, Hsieh JF, Tsai SC, Ho YJ, Lee JK, Kao CH. Monitoring the effect of anticoagulants on left atrial thrombi in patients with rheumatic heart disease: assessment with 111In-oxine-labelled platelet heart scintigraphy and transoesophageal echocardiography. Nucl Med Commun 2000; 21:627-30. [PMID: 10994665 DOI: 10.1097/00006231-200007000-00005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
111In-oxine-labelled platelet heart scintigraphy (In-plt) was used to evaluate the activity of left atrial thrombi detected by transoesophageal echocardiography (TEE) in 16 cases of rheumatic heart disease. The effect of anticoagulants on the therapeutic intervention of these patients was evaluated by In-plt and TEE. In-plt was performed in all patients in serial pre- and post-anticoagulant therapy studies with anterior, 45 degrees left anterior oblique and left lateral views taken daily from the second to sixth day after injection of labelled platelets. After discontinuing anticoagulants for at least 1 week, only nine cases of left atrial thrombi were detected among the 16 cases by initial In-plt. After anticoagulants were again used for at least 3 weeks, all nine positive cases became negative on repeat In-plt. These results suggest that the diagnostic sensitivity of In-plt is lower than that of TEE. However, In-plt is more suitable and useful for evaluating the activity of left atrial thrombi after antithrombotic agent therapy and for monitoring the effect of anticoagulant therapy on left atrial thrombi in patients with rheumatic heart disease.
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319
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Magin RL, Lee JK, Klintsova A, Carnes KI, Dunn F. Biological effects of long-duration, high-field (4 T) MRI on growth and development in the mouse. J Magn Reson Imaging 2000; 12:140-9. [PMID: 10931573 DOI: 10.1002/1522-2586(200007)12:1<140::aid-jmri15>3.0.co;2-d] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The effects of long-duration, high-field magnetic resonance imaging (MRI) on fetal growth and postnatal development in mice were studied. Seven experimental groups of pregnant ICR mice were exposed for 9 hours on day 9 and/or day 12 post coitus (pc) to magnetic fields (4 T static, 5 T/sec switched gradient, and 0.2 W/kg radiofrequency at 170 MHz) associated with MRI conditions. Two experimental groups (sham and exposure groups) were exposed to a combination of ultrasound (day 9 pc, 3.25 MHz, focused) and MRI-associated fields (day 12 pc). No statistically significant changes in fetal growth were observed in the animals exposed to only MRI or ultrasound fields. However, in the combined ultrasound and MRI-exposed group, the fetal weight and crown-rump length were reduced compared with the sham and cage controls. These results suggest that MRI and ultrasound exposure well in excess of current clinical conditions can exert biological effects if applied at sensitive stages of fetal development.
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320
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Kensler TW, Dolan PM, Gange SJ, Lee JK, Wang Q, Posner GH. Conceptually new deltanoids (vitamin D analogs) inhibit multistage skin tumorigenesis. Carcinogenesis 2000; 21:1341-5. [PMID: 10874012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Development of vitamin D analogs (deltanoids) as chemopreventive agents requires separation of desirable antiproliferative and pro-differentiating activities from the undesirable calcemic activity also found in the hormone calcitriol (1 alpha, 25-dihydroxyvitamin D(3)). Therefore, several conceptually new deltanoids were synthesized with modifications to the 1alpha- and/or 25-hydroxyl groups, positions traditionally considered essential for stimulating biological responses. In this study, 1 beta-hydroxymethyl-3-epi-25-hydroxyvitamin D(3), a non-calcemic CH(2) homolog of the natural hormone with antiproliferative activity in vitro, was ineffective as an inhibitor of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced induction of ornithine decarboxylase activity in mouse epidermis. However, a hybrid analog incorporating not only the calcemia-ablating 1 beta-hydroxymethyl alteration, but potentiating C,D ring 16-unsaturation and side chain 24,24-fluorination and 26, 27-homologation was found to be as effective as calcitriol. Several non-calcemic 24- or 25-t-butyl sulfones, some containing side chain fluorination but all lacking the 25-hydroxyl group, were also shown to be active in this assay. Three sulfones and the 1 beta-hydroxymethyl hybrid were evaluated as inhibitors of multistage carcinogenesis in mouse skin. Female CD-1 mice were initiated with a single dose of 7,12-dimethylbenz[a]anthracene and then promoted twice weekly for 20 weeks with TPA. Deltanoids were applied topically 30 min before TPA. Unlike calcitriol, none of the atypical deltanoids affected body weight gain in these animals. Minimal effects on urinary calcium excretion were observed following chronic treatment with these analogs. All deltanoids inhibited the incidence and multiplicity of papilloma formation, with the hybrid analog showing the greatest efficacy. With this deltanoid, tumor incidence was significantly reduced by 28% and tumor multiplicity by 63%. These results, coupled with the rich chemical diversity available in side chain sulfur-containing deltanoids, particularly when combined with A ring modifications such as 1 beta-hydroxylalkyl groups, provide important new advances in the fundamental understanding of chemical structure-biological activity relationships as well as more potent and safe vitamin D analogs for cancer chemoprevention and other medicinal uses.
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Federle MP, Chezmar JL, Rubin DL, Weinreb JC, Freeny PC, Semelka RC, Brown JJ, Borello JA, Lee JK, Mattrey R, Dachman AH, Saini S, Harmon B, Fenstermacher M, Pelsang RE, Harms SE, Mitchell DG, Halford HH, Anderson MW, Johnson CD, Francis IR, Bova JG, Kenney PJ, Klippenstein DL, Foster GS, Turner DA. Safety and efficacy of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. multicenter phase III clinical trials (safety). J Magn Reson Imaging 2000; 12:186-97. [PMID: 10931579 DOI: 10.1002/1522-2586(200007)12:1<186::aid-jmri21>3.0.co;2-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The short-term safety of mangafodipir trisodium (MnDPDP) injection was studied in 546 adults with known or suspected focal liver lesions. An initial contrast-enhanced computed tomography examination was followed by unenhanced magnetic resonance imaging (MRI), injection of MnDPDP (5 micromol/kg), and enhanced MRI. Adverse events were reported for 23% of the patients; most were mild to moderate in intensity, did not require treatment, and were not drug related. The most commonly reported adverse events were nausea (7%) and headache (4%). The incidence of serious adverse events was low (nine events in six patients) and not drug related. Injection-associated discomfort was reported for 69% of the patients, and the most commonly reported discomforts included heat (49%) and flushing (33%). Changes in laboratory values and vital signs were generally transient, were not clinically significant, and did not require treatment. There were no clinically significant short-term risks from exposure to MnDPDP.
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322
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Hahm JK, Park YW, Lee JK, Choi JY, Sul JH, Lee SK, Cho BK, Choe KO. Magnetic resonance imaging of unroofed coronary sinus: three cases. Pediatr Cardiol 2000; 21:382-7. [PMID: 10865020 DOI: 10.1007/s002460010087] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Unroofed coronary sinus is a rare cardiac anomaly in which communication occurs between the coronary sinus and the left atrium due to the partial or complete absence of the roof of the coronary sinus. It is usually associated with other cardiovascular anomalies, especially persistent left superior vena cava. It is often not discovered during cardiac catheterization without clinical suspicion. We report three cases of unroofed coronary sinus which were incidentally detected by magnetic resonance imaging.
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Lee JK, Hong YJ, Han CJ, Hwang DY, Hong SI. Clinical usefulness of serum and plasma vascular endothelial growth factor in cancer patients: which is the optimal specimen? Int J Oncol 2000; 17:149-52. [PMID: 10853032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) is secreted by various human cancer cells and plays a key role in cancer angiogenesis and metastasis. Recently, evidence of VEGF storage in blood cells including platelets has been reported. The serum VEGF levels were reported to increase during clotting as a result of its release from platelets, and plasma sample instead of serum was recommended for measuring the circulating VEGF more accurately. However, platelets have been implicated in tumor metastasis since circulating tumor cells forming aggregates with platelets were observed. The purpose of this study was to clarify which is an optimal specimen to measure VEGF in cancer patients, serum or plasma. We measured serum and plasma VEGF levels and platelet counts in 173 cancer patients and 42 healthy people, and found that serum VEGF levels were significantly higher than matched plasma VEGF and the VEGF difference (serum VEGF - plasma VEGF) correlated with platelet counts (r=0.624, p<0.05) in both cancer patients and healthy controls. We selected cancer patients with normal platelet counts (130-400x103/microl, Plt-normal cancer group). Interestingly, serum VEGF levels were higher in Plt-normal cancer group than in healthy controls. The theoretical platelet-derived VEGF in serum, calculated based on actual blood platelet counts (pg per 106 platelets), was also significantly higher in Plt-normal cancer group than in normal controls. It is, therefore, suggested that, although the serum VEGF levels are affected by blood platelets, platelet-derived VEGF also reflect biology of cancer cells, and that serum would be the more useful specimen for measurement of circulating VEGF in cancer patients for prognosis.
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324
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Lee JK, Choi MR, Paek SH, Song DK, Huh SO, Kim YH, Suh HW. Differential effects of cholera toxin and pertussis toxin on the c-fos and c-jun mRNA expression in rat C6 glioma cells. Mol Cells 2000; 10:325-30. [PMID: 10901171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Cholera toxin (CTX) increased c-fos mRNA level whereas it down-regulated the c-jun mRNA level in rat C6 glioma cells. In contrast to the action of CTX, pertussis toxin (PTX) did not affect either c-fos or c-jun mRNA level. The elevated c-fos mRNA level induced by CTX was significantly inhibited by the co-treatment with dexamethasone (DEX). However, DEX did not affect CTX-induced down-regulation of c-jun mRNA level. Cycloheximide (CHX) increased c-fos and c-jun mRNA levels. CHX caused a super-induction of CTX-induced c-fos mRNA level. Our results suggest that CTX-, but not PTX-, sensitive G-proteins may play an important role for c-fos mRNA up-regulation and c-jun mRNA down-regulation. In addition, DEX appears to have a selective inhibitory action against c-fos mRNA expression regulated by CTX. Ongoing protein synthesis inhibition is required for the superinduction of c-fos, but not c-jun, mRNA induced by CTX.
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MESH Headings
- Animals
- Blotting, Northern
- Cholera Toxin/metabolism
- Cholera Toxin/pharmacology
- Culture Media, Serum-Free
- Cycloheximide/pharmacology
- DNA, Complementary
- Dexamethasone/pharmacology
- GTP-Binding Proteins/metabolism
- Gene Expression Regulation/drug effects
- Genes, fos
- Genes, jun
- Neuroglia/cytology
- Neuroglia/metabolism
- Pertussis Toxin
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Time Factors
- Tumor Cells, Cultured
- Virulence Factors, Bordetella/metabolism
- Virulence Factors, Bordetella/pharmacology
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325
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Ho YJ, Hsieh JF, Tasi SC, Lee JK, Kao CH. Tissue polypeptide specific antigen and squamous cell carcinoma antigen for early prediction of recurrence in lung squamous cell carcinoma. Lung 2000; 178:75-80. [PMID: 10773133 DOI: 10.1007/s004080000010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
One of the major problems in the follow-up of patients with lung cancer is the early detection of recurrent disease. Tumor markers have been found helpful in detecting early recurrent disease. The aims of this study were to evaluate and compare the clinical usefulness of serial and simultaneous measurement of tissue polypeptide antigen (TPS) and squamous cell carcinoma (SCC) antigen for the early prediction of recurrence in patients with SCC of the lung. Sixty patients with SCC of the lung, including 25 patients with recurrence and 35 patients without recurrence after 1 year's follow-up after surgery, were enrolled in this study. The serial serum levels of TPS and SCC antigen were measured before surgery and 1 week, 1 month, 3 months, 6 months, 9 months, and 12 months after the operation for early detection of recurrence. The results revealed that (1) the mean serum values of TPS were significantly greater at all times after surgery in the 25 patients with recurrent SCC compared with the 35 patients without recurrent SCC, and (2) the mean serum values of SCC antigen were significantly greater only at 9 and 12 months after surgery in the 25 patients with recurrent SCC compared with the 35 patients without recurrent SCC. We conclude that TPS is a better marker than SCC antigen for early prediction of SCC recurrence in the lung.
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