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Lee JH, Lee JM, Lim KH, Kim JK, Ahn SK, Bang YJ, Hong CI. Preclinical and phase I clinical studies with Ckd-602, a novel camptothecin derivative. Ann N Y Acad Sci 2001; 922:324-5. [PMID: 11193913 DOI: 10.1111/j.1749-6632.2000.tb07055.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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1102
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Lee JH, Seo JM, Kim M, Kim JC. Cloning of cDNA for a novel fibrinogen/angiopoietin-related protein, FARP. Mol Cells 2001; 11:100-4. [PMID: 11266110] [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] Open
Abstract
Using a low abundant gene screening strategy in the human dermal papilla cell cDNA library, we isolated a novel cDNA, which was 1,872 bp of nucleotides in length and contained an open reading frame encoding 405 amino acids. We designated it 'fibrinogen/angiopoietin-related protein' (FARP) as it contained the characteristic coiled-coil domain and fibrinogen-like domain in the NH2- and COOH-terminal, which are conserved in angiopoietins. FARP has a highly hydrophobic region at the N-terminus that is typical of a secretory signal sequence. Recently, a very similar gene, HFARP, was cloned and they have a difference of only 18 amino acids in N-terminus. While HFARP was expressed only in the liver, northern blot analysis showed that FARP mRNA is abundantly expressed in the liver, placenta, prostate, and ovary in human adult tissues. It was also expressed in the fetal liver and lung carcinoma cell line. Further study will be needed to clarify the function of the FARP gene.
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1103
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Chung JG, Chen GW, Hung CF, Lee JH, Ho CC, Ho HC, Chang HL, Lin WC, Lin JG. Effects of berberine on arylamine N-acetyltransferase activity and 2-aminofluorene-DNA adduct formation in human leukemia cells. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2001; 28:227-38. [PMID: 10999441 DOI: 10.1142/s0192415x00000271] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Berberine is an alkaloid occurring in the plant genera Berberis and Coptis. Although berberine had been demonstrated to have antineoplastic function by inhibiting DNA-synthesis in activated lymphocytes, there is no available information to address berberine affects on human leukemia cell N-acetyltransferase (NAT) activity and 2-aminofluorene (AF)-DNA adduct formation. Thus, berberine was tested for inhibition of arylamine NAT activity and AF-DNA adduct formation in human leukemia cells. The NAT activity was measured by a high performance liquid chromatography assaying for the amounts of N-acetyl-2-aminofluorene (AAF) and N-acetyl-p-aminobenzoic acid (N-Ac-PABA) and the remaining AF and p-aminobenzoic acid (PABA). The NAT activity and AF-DNA adduct formation in human leukemia cells were inhibited by berberine in a dose-dependent manner, i.e. the higher the concentration of berberine, the higher the inhibition of NAT activity and AF-DNA adduct. The data also indicate that berberine decreased the apparent values of Km and Vmax from human leukemia cells in both cytosol and intact cells.
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1104
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Han HJ, Lee JH, Park SH, Choi HJ, Yang IS, Mar WC, Kang SK, Lee HJ. Effect of bee venom and its melittin on apical transporters of renal proximal tubule cells. Kidney Blood Press Res 2001; 23:393-9. [PMID: 11070419 DOI: 10.1159/000025988] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Renal failure by bee venom may be related to a malfunction of renal transporters. However, the effects of bee venom on apical membrane transporters of renal proximal tubular cells are not yet known. The aim of this study was to examine the effects of dried bee venom of Apis mellifera and its melittin on apical transporter activity of primary cultured rabbit kidney proximal tubule cells. Bee venom (1 microg/ml) decreased the cell viability and increased lactate dehydrogenase activity over 30-min treatments. Its effect was blocked by mepacrine or AACOCF(3) (10(-6) M; phospholipase A(2) inhibitors). However, there was no effect on cell viability at a concentration of 0.01 microg/ml of bee venom. Thus, we investigated the effect of bee venom (1 microg/ml) on the activity of renal transporters at 30 min. Bee venom inhibited alpha-methyl-D-glucopyranoside, Pi, and Na(+) uptakes, but increased Ca(2+) uptake. These effects of bee venom were blocked by mepacrine or AACOCF(3) (10(-6) M), and bee venom-induced stimulation of Ca(2+) uptake was also blocked by methoxyverapamil and nifedipine (L-type calcium channel blockers). In addition, bee venom increased [(3)H]-arachidonic acid release by 216 % of that of control. In all experiments, bee venom melittin (0.5 microg/ml) had an identical effect to that of bee venom itself. In conclusion, bee venom inhibited, in part, alpha-MG, Pi, and Na(+) uptakes through its melittin which increased Ca(2+) uptake and arachidonic acid release in primary cultured rabbit renal proximal tubule cells.
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1105
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Lee JH, Park HJ, Kim YC, Cinn YW. Two cases of Kimura's disease with unusual clinical manifestations. Dermatology 2001; 201:162-4. [PMID: 11053923 DOI: 10.1159/000018463] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We report 2 cases of Kimura's disease with unusual clinical presentation. Lesions were itching nodules located at the elbow and the dorsum of the hand, and were associated with unusual laboratory values. These features may lead to problems in clinical differential diagnosis.
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1106
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Jhoo JH, Kim KW, Lee DY, Lee KU, Lee JH, Kim SY, Youn JY, Youn JC, Woo JI. Association of alpha-2-macroglobulin deletion polymorphism with sporadic Alzheimer's disease in Koreans. J Neurol Sci 2001; 184:21-5. [PMID: 11231028 DOI: 10.1016/s0022-510x(00)00494-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Alpha-2-macroglobulin (A2M) deletion polymorphism was recently reported to be associated with Alzheimer's disease (AD) in a way comparable to apolipoprotein E (APOE) polymorphism in a family-based study. However, the association of A2M deletion polymorphism with AD has not been consistently replicated in successive case-controlled studies. In order to evaluate whether this A2M polymorphism is associated with AD in Koreans, we examined the frequencies of the A2M deletion (D) allele and D-bearing genotypes in a group of Koreans composed of 100 sporadic AD patients and 203 control subjects. The frequency of the deletion (D) allele (P=0.046) was significantly different between the total group of AD patients and the controls, although the frequency of the D-bearing genotypes did not attain significance (P=0.078). When the subjects were stratified according to age at onset, there was significant difference in the frequencies of the D allele (P=0.044) and D-bearing genotypes (P=0.041) between late-onset AD patients (> or =65 years) and the controls. However, no significant difference was observed between early-onset AD patients (<65 years) and the control group. Additionally, when we divided the late-onset AD and control subjects by APOE epsilon4 status, the difference of the A2M D allelic frequency was significant only in the APOE epsilon4 negative subjects (P=0.015). In conclusion, our data suggests that the A2M D allele is a modest risk factor for late-onset sporadic AD in Koreans, and the AD risk conferred by the A2M D allele increases in APOE epsilon4 negative subjects.
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1107
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Rothbaum BO, Hodges L, Smith S, Lee JH, Price L. A controlled study of virtual reality exposure therapy for the fear of flying. J Consult Clin Psychol 2001. [PMID: 11142535 DOI: 10.1037//0022-006x.68.6.1020] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fear of flying (FOF) affects an estimated 10-25% of the population. Patients with FOF (N = 49) were randomly assigned to virtual reality exposure (VRE) therapy, standard exposure (SE) therapy, or a wait-list (WL) control. Treatment consisted of 8 sessions over 6 weeks, with 4 sessions of anxiety management training followed by either exposure to a virtual airplane (VRE) or exposure to an actual airplane at the airport (SE). A posttreatment flight on a commercial airline measured participants' willingness to fly and anxiety during flight immediately after treatment. The results indicated that VRE and SE were both superior to WL, with no differences between VRE and SE. The gains observed in treatment were maintained at a 6-month follow up. By 6 months posttreatment, 93% of VRE participants and 93% of SE participants had flown. VRE therapy and SE therapy for treatment of FOF were unequivocally supported in this controlled study.
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1108
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Yoon UC, Oh SW, Lee JH, Park JH, Kang KT, Mariano PS. Applications of phthalimide photochemistry to macrocyclic polyether, polythioether, and polyamide synthesis. J Org Chem 2001; 66:939-43. [PMID: 11430116 DOI: 10.1021/jo001457u] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Irradiation of phthalimides which contain N-linked omega-trimethylsilylmethyl-substituted polyether, polythioether, and polysulfonamide chains results in efficient production of the corresponding macrocyclic polyether, polythioether, and polysulfonamide products. These photocyclization reactions follow sequential single electron transfer (SET)-desilylation pathways. Only in the cases of phthalimides, bearing mixed ether-thioether N-substituents, do these excited-state cyclization reactions proceed with lower degrees of regioselectivity. This is a result of competitive desilylation and alpha-to-sulfur deprotonation reactions of the zwitterionic diradical intermediates formed by initial SET.
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1109
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Ku SK, Lee HS, Lee JH, Park KD. An immunohistochemical study on the endocrine cells in the alimentary tract of the red-eared slider (Trachemys scripta elegans). Anat Histol Embryol 2001; 30:33-9. [PMID: 11284161 DOI: 10.1046/j.1439-0264.2001.00284.x] [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: 11/20/2022]
Abstract
The regional distribution and relative frequency of endocrine cells in the alimentary tract of the red-eared slider, Trachemys scripta elegans, were investigated by immunohistochemical methods using 10 antisera. Most of the immunoreactive cells in the intestine were spherical or spindle-like in shape (open-type cells), while round cells (closed-type cells) were occasionally found in the stomach. These immunoreactive cells were located in the basal portion of the intestine, including the oesophagus, and in the gastric glands of the stomach. Cg A-immunoreactive cells were restricted to the pylorus and duodenum and were few in number. Serotonin-immunoreactive cells, which were most commonly found in the pylorus, were found in the epithelia throughout the alimentary tract at various frequencies. Gastrin-immunoreactive cells were found in the pylorus, duodenum and jejunum at moderate, low and very low frequencies, respectively. Somatostatin-immunoreactive cells were found throughout the alimentary tract except for the rectum, at various frequencies. Glucagon-immunoreactive cells were detected in the fundus, pylorus, jejunum and ileum at low or very low frequencies. CCK-8-immunoreactive cells were found in the pylorus, fundus and duodenum at very low, low and moderate frequencies, respectively. Bombesin-immunoreactive cells were restricted to the fundus and pylorus at low frequencies. No secretin-, BPP- or VIP-immunoreactive cells were found in this study.
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1110
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Lee JH, Koh JT, Shin BA, Ahn KY, Roh JH, Kim YJ, Kim KK. Comparative study of angiostatic and anti-invasive gene expressions as prognostic factors in gastric cancer. Int J Oncol 2001; 18:355-61. [PMID: 11172604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Genes involving angiogenesis and metastasis play an important role in the progression and infiltration of cancer. We examined the expressions of various angiostatic and potential invasion/metastasis suppressor genes through RT-PCR analyses in 32 gastric cancer specimens with or without distant metastasis. The expressions of the invasion/metastasis suppressor, nm23 and E-cadherin increased much more in the cancer tissue (CT) and metastatic lymph node (MLN) than in the extraneoplastic mucosa (EM) and non-metastatic lymph node (NLN), respectively. The expressions of the angiostatic factor, angiopoietin 2 and thrombospondin 2 increased in the CT and MLN as compared with the EM and NLN, respectively. The newly cloned angiostatic factor, brain-specific angiogenesis inhibitor 1 (BAI1) decreased much more in the CT and MLN than the EM and NLN, respectively. However, BAI1 increased in the CT compared with the EM among the patients with poor prognosis and distant metastasis, such as liver or peritoneum. The expressions of the invasive factor, matrix metalloproteinase-2 and its suppressor, tissue inhibitor metalloproteinase-2 (TIMP-2) increased in the CM as compared with the EM, but the increased expression pattern of these genes in the CT became blunted among the patients with good prognosis. Our results indicate that BAI1 and TIMP-2 expressions in the extraneoplastic mucosa and non-metastatic lymph nodes were not suppressed in the patients with good prognosis, but increased expressions of angiopoietin 2, thrombospondin 2, TIMP-2, nm23 and E-cadherin in the tumor tissue did not lead to a long survival after operation. It is suggested that the extent of BAI1 and TIMP-2 expression in the gastric mucosa may be an important prognostic factor for predicting survival in gastric cancer.
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1111
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Lee JH, Lee JH, Kim TW, Lee KH, Kang YK, Lee JS, Kim SH, Kim HC, Yu CS, Kim JC, Kim WK. Combination of oxaliplatin, fluorouracil, and leucovorin in the treatment of fluoropyrimidine-pretreated patients with metastatic colorectal cancer. J Korean Med Sci 2001; 16:69-74. [PMID: 11289404 PMCID: PMC3054558 DOI: 10.3346/jkms.2001.16.1.69] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There has been no standard therapy for patients with metastatic colorectal cancer who have failed to first-line fluorouracil-based treatment. The present study was designed to assess the efficacy and toxicities of a combination of oxaliplatin, 5-fluorouracil (5-FU) and leucovorin in fluoropyrimidine-pretreated patients with metastatic colorectal cancer. Chemotherapy consisted of oxaliplatin 85 mg/m2 on day 1, followed by leucovorin 20 mg/m2 and 5-FU 1,200 mg/m2 on days 1 and 2. Treatment courses were repeated every two weeks. Thirty-nine patients were enrolled in this study. All patients previously received fluoropyrimidine-based chemotherapy. Thirty-one patients were assessable for response and 33 for treatment toxicity. Six patients required dose reduction of 5-FU due to grade III/IV cytopenia. Nausea/vomiting and peripheral neuropathy were common non-hematologic toxicities. Overall response rate was 42.0% including 3 complete response and 10 partial response. The median response duration was 91 days (range, 28-224+). The median duration of progression-free survival was 132 days (range, 40-308). A combination of oxaliplatin, 5-FU, and leucovorin showed high response rate in fluoropyrimidine-pretreated patients with metastatic colorectal cancer, but the duration of response was relatively short. It may be worthwhile to explore its therapeutic potential in the first-line treatment setting.
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1112
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Abstract
BACKGROUND Livedoid vasculitis is a chronic disorder manifested as recurrent, painful, reticulated, and ulcerative lesions of the legs, which result in ivory atrophic scars with peripheral telangiectasia and hyperpigmentation. Its etiology remains obscure and therapy is difficult. In this study, we evaluated the clinical efficacy of psoralen plus UVA (PUVA) therapy and its side-effects in the treatment of livedoid vasculitis. METHODS Eight South Korean patients with livedoid vasculitis were treated with UVA and 8-methoxypsoralen (8-MOP). Systemic PUVA was started with 4 J/cm2 of UVA two or three times a week, and then the dose was increased by 0.5 or 1 J/cm2 increments at each subsequent treatment as tolerated. The effects of treatment were evaluated using photographs of before, during, and after the study. RESULTS All patients experienced rapid cessation of new lesion formation, significant symptom relief, and complete healing of primary lesions. The mean times for each of the above were 3.6, 5.9, and 10 weeks, and the mean cumulative doses of UVA for each of the above were 55.9, 96.8, and 197.9 J/cm2, respectively. The patients tolerated PUVA therapy well without unacceptable side-effects. CONCLUSIONS We propose that systemic PUVA using 8-MOP should be investigated further as an alternative treatment for patients with livedoid vasculitis.
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1113
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Lee JH, Chon CY, Ahn SH, Moon BS, Kim JH, Paik YH, Han KH, Lee JT, Lee DY, Moon YM. An ischemic skin lesion after chemoembolization of the right internal mammary artery in a patient with hepatocellular carcinoma. Yonsei Med J 2001; 42:137-41. [PMID: 11293493 DOI: 10.3349/ymj.2001.42.1.137] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A huge nodular hepatocellular carcinoma located at the anterior superior portion of the left lobe in a patient with hepatocellular carcinoma was treated with transcatheter arterial chemoembolization through the left hepatic artery. Three months later, however, there was a re-elevation of the serum alpha-fetoprotein level and evidence of a marginal recurrence at the left side of the previously embolized tumor was noted on the postembolization computed tomographic scan. Although the hepatic artery was intact in the second hepatic arteriography, we found that the right internal mammary artery was feeding the recurred hepatocellular carcinoma. This internal mammary artery was successfully treated with Lipiodol-transcatheter arterial chemoembolization. However, an ischemic lesion occurred in the skin of the anterior chest and abdominal wall several days after internal mammary artery embolization. We report here a very rare case of ischemic skin lesion on the anterior chest and abdominal wall following transcatheter arterial chemoembolization of the right internal mammary artery. This internal mammary artery was embolized because it had developed a collateral tumor feeding vessel following the initial chemoembolization of a hepatocellular carcinoma.
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1114
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Lee JH, Chung CK, Kim HJ. Cerebral dissection from syringomyelia demonstrated using cine magnetic resonance imaging. Case report. J Neurosurg 2001; 94:318-21. [PMID: 11213972 DOI: 10.3171/jns.2001.94.2.0318] [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: 11/06/2022]
Abstract
A 16-year-old boy presented at the authors' emergency department with a sudden deterioration of respiration. He had been paraparetic for 3 years and had become quadriplegic 2 days previously. Magnetic resonance images revealed a Chiari I malformation and a hydromyelic cavity extending from C-1 to T-11. Rostrally, a small cylindrically shaped lesion extended from the cervicomedullary junction to the left semioval center. The patient made a dramatic neurological recovery following suboccipital craniectomy and upper cervical laminectomies with augmentation duraplasties followed by placement of a syringoperitoneal shunt.
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1115
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Li YH, Lau PC, Lee JH, Ellen RP, Cvitkovitch DG. Natural genetic transformation of Streptococcus mutans growing in biofilms. J Bacteriol 2001; 183:897-908. [PMID: 11208787 PMCID: PMC94956 DOI: 10.1128/jb.183.3.897-908.2001] [Citation(s) in RCA: 434] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Streptococcus mutans is a bacterium that has evolved to be dependent upon a biofilm "lifestyle" for survival and persistence in its natural ecosystem, dental plaque. We initiated this study to identify the genes involved in the development of genetic competence in S. mutans and to assay the natural genetic transformability of biofilm-grown cells. Using genomic analyses, we identified a quorum-sensing peptide pheromone signaling system similar to those previously found in other streptococci. The genetic locus of this system comprises three genes, comC, comD, and comE, that encode a precursor to the peptide competence factor, a histidine kinase, and a response regulator, respectively. We deduced the sequence of comC and its active pheromone product and chemically synthesized the corresponding 21-amino-acid competence-stimulating peptide (CSP). Addition of CSP to noncompetent cells facilitated increased transformation frequencies, with typically 1% of the total cell population transformed. To further confirm the roles of these genes in genetic competence, we inactivated them by insertion-duplication mutagenesis or allelic replacement followed by assays of transformation efficiency. We also demonstrated that biofilm-grown S. mutans cells were transformed at a rate 10- to 600-fold higher than planktonic S. mutans cells. Donor DNA included a suicide plasmid, S. mutans chromosomal DNA harboring a heterologous erythromycin resistance gene, and a replicative plasmid. The cells were optimally transformed during the formation of 8- to 16-h-old biofilms primarily consisting of microcolonies on solid surfaces. We also found that dead cells in the biofilms could act as donors of a chromosomally encoded antibiotic resistance determinant. This work demonstrated that a peptide pheromone system controls genetic competence in S. mutans and that the system functions optimally when the cells are living in actively growing biofilms.
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1116
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Mason P, Escobedo I, Burgin C, Bergan J, Lee JH, Last EJ, Holub AL. Nociceptive responsiveness during slow-wave sleep and waking in the rat. Sleep 2001; 24:32-8. [PMID: 11204051 DOI: 10.1093/sleep/24.1.32] [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: 11/15/2022] Open
Abstract
Brainstem neurons that are thought to modulate pain are reported to have state-dependent discharge rates. Yet, the effect of behavioral state upon nociceptive transmission has not been well studied. Therefore, we examined responses to noxious thermal stimulation of the rat hindpaw presented during different behavioral states. Noxious thermal stimuli were applied to rats as they spontaneously cycled through waking and sleeping states. Two different methods of heating the paw - a focused light bulb ("radiant heat") and a CO2 laser ("laser heat")-were employed. Regardless of the heating method used, rats withdrew from noxious thermal stimulation when it was applied in each behavioral state tested. When rats were tested with radiant heat, the withdrawal latency from noxious heat was shorter during slow-wave sleep than during waking. In contrast, when tested with laser heat, there was no difference in either the response latency or magnitude evoked by noxious heat across sleep/wake states. Despite the fact that rats withdrew from noxious heat (using either method of application) applied during sleep, the rats quickly returned to sleep afterwards. The latency to sleep after noxious stimulation was significantly greater during waking than during sleeping. The behavioral response to noxious thermal stimulation includes both an initial motor withdrawal which is enhanced during sleep and arousal or alerting which is suppressed during sleep. Therefore, pain evokes at least two distinct reactions that are differentially modulated across sleep/wake cycles.
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1117
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Reddy DK, Moore HL, Lee JH, Saran R, Nolph KD, Khanna R, Twardowski ZJ. Chronic peritoneal dialysis in iron-deficient rats with solutions containing iron dextran. Kidney Int 2001; 59:764-73. [PMID: 11168960 DOI: 10.1046/j.1523-1755.2001.059002764.x] [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: 11/20/2022]
Abstract
BACKGROUND We evaluated the effects of different concentrations of iron dextran administered through the intraperitoneal route, in iron-deficient rats, on hematocrit (Hct in percentage), serum iron (mg/dL), total iron binding capacity (TIBC in mg/dL), and the function and histology of the peritoneal membrane. METHODS Seventy-two male Sprague-Dawley rats weighing 85 to 110 g were divided into two groups and seven subgroups. Group I consisted of rats on iron-deficient chow, and group II consisted of rats on normal chow. Both groups contained dialysis control subgroups (N = 12: IA, IID), dialyzed with Dianeal solution, and tissue control subgroups (N = 6: IE, IIN), in which rats were not dialyzed and catheters were not implanted. Study group I contained the following study subgroups (N = 12): (B) rats dialyzed with Dianeal solution containing 2 mg/L of iron dextran and (C) rats dialyzed with Dianeal solution containing 1 mg/L of iron dextran. Group IID was dialyzed with Dianeal solution containing 2 mg/dL of iron dextran. Study duration was 12 weeks with peritoneal equilibration tests (PETs) performed at baseline, 6 weeks, and 12 weeks. Prior to baseline, rats were placed on iron-deficient chow or normal chow for three weeks. Dialysis was performed with three 25 mL volume exchanges per day. Hematocrit (Hct), serum iron (Fe), and total iron binding capacity (TIBC) were determined for each study interval. After the final PET, the animals were sacrificed, and the peritoneal membrane was evaluated by gross inspection and light microscopy. RESULTS Rats on an iron-deficient diet developed severe iron-deficiency anemia after three weeks of the diet (Hct 27; Fe 21 to 23; TIBC 799 to 806). After 12 weeks, the rats remained anemic in groups A (Hct 34 +/- 0.9; Fe 16 +/- 2; TIBC 998 +/- 27) and IE (Hct 38 +/- 2.7), whereas the rats corrected anemia in group B (Hct 45.8 +/- 1.8; Fe 115 +/- 15; TIBC 546 +/- 77). The results were not significantly different from those of group IID (Hct 47.1 +/- 1.6; Fe 94 +/- 19; TIBC 516 +/- 46). In group C, Hct (44.8 +/- 2.1) and Fe (94 +/- 19) did not differ significantly from group IID, but TIBC (734 +/- 76) remained significantly higher than that in the group IID. Peritoneal iron deposits were not detected. The morphometric analysis of the submesothelial space did not reveal any difference in thickness between dialysis groups. PETs were not significantly different among groups. CONCLUSIONS Intraperitoneal iron dextran supplementation in concentrations of 2 mg/L of dialysis solution is nontoxic to the peritoneum and effective in correcting iron deficiency in rats maintained on an iron-deficient diet. Iron dextran in concentration of 1 mg/L of dialysis solution may be sufficient for correcting a lesser degree of iron deficiency.
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1118
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Pai H, Kim J, Kim J, Lee JH, Choe KW, Gotoh N. Carbapenem resistance mechanisms in Pseudomonas aeruginosa clinical isolates. Antimicrob Agents Chemother 2001; 45:480-4. [PMID: 11158744 PMCID: PMC90316 DOI: 10.1128/aac.45.2.480-484.2001] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
In order to define the contributions of the mechanisms for carbapenem resistance in clinical strains of Pseudomonas aeruginosa, we investigated the presence of OprD, the expressions of the MexAB-OprM and MexEF-OprN systems, and the production of the beta-lactamases for 44 clinical strains. All of the carbapenem-resistant isolates showed the loss of or decreased levels of OprD. Three strains overexpressed the MexAB-OprM efflux system by carrying mutations in mexR. These three strains had the amino acid substitution in MexR protein, Arg (CGG) --> Gln (CAG), at the position of amino acid 70. None of the isolates, however, expressed the MexEF-OprN efflux system. For the characterization of beta-lactamases, at least 13 isolates were the depressed mutants, and 12 strains produced secondary beta-lactamases. Based on the above resistance mechanisms, the MICs of carbapenem for the isolates were analyzed. The MICs of carbapenem were mostly determined by the expression of OprD. The MICs of meropenem were two- to four-fold increased for the isolates which overexpressed MexAB-OprM in the background of OprD loss. However, the elevated MICs of meropenem for some individual isolates could not be explained. These findings suggested that other resistance mechanisms would play a role in meropenem resistance in clinical isolates of P. aeruginosa.
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1119
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Lee SH, Shin MS, Kim HS, Lee HK, Park WS, Kim SY, Lee JH, Han SY, Park JY, Oh RR, Kang CS, Kim KM, Jang JJ, Nam SW, Lee JY, Yoo NJ. Somatic mutations of TRAIL-receptor 1 and TRAIL-receptor 2 genes in non-Hodgkin's lymphoma. Oncogene 2001; 20:399-403. [PMID: 11313970 DOI: 10.1038/sj.onc.1204103] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2000] [Revised: 11/08/2000] [Accepted: 11/09/2000] [Indexed: 11/08/2022]
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand-receptor 1 (TRAIL-R1) and tumor necrosis factor-related apoptosis-inducing ligand-receptor 2 (TRAIL-R2) are cell-surface receptors involved in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced cell-death signaling. TRAIL-R1 and TRAIL-R2 genes have recently been mapped to chromosome 8p21-22, which is a frequent site of allelic deletions in many types of human tumors, including non-Hodgkin's lymphoma (NHL). Because TRAIL/TRAIL receptor system plays an important role in lymphocyte homeostasis, we hypothesized that the mutations of TRAIL-R1 and TRAIL-R2 may be involved in the development of NHL and that such mutations may be responsible for the allelic losses of 8p21-22 in NHL. In this study, we analysed the entire coding region of TRAIL-R2 gene and the death domain region of TRAIL-R1 gene for the detection of the somatic mutations in a series of 117 human NHLs using polymerase chain reaction (PCR)-based single strand conformation polymorphism (SSCP) analysis. Overall, eight tumors (6.8%) were found to have two TRAIL-R1 gene mutations or six TRAIL-R2 gene mutations. Interestingly, of the eight mutations, six missense mutations (two TRAIL-R1 and four TRAIL-R2) were detected in the death domains and one nonsense mutation of TRAIL-R2 was detected just before the death domain. Our data suggest that somatic mutations of TRAIL-R1 and TRAIL-R2 genes may play a role in the pathogenesis of some NHLs and that TRAIL-R1 and TRAIL-R2 genes might be the relevant genes to the frequent loss of chromosome 8p21-22 in human NHL.
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1120
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Kim D, Koh WK, Kim JU, Lee JH, Hong HN. Okadaic acid-induced upregulation of nitrotyrosine and heme oxygenase-1 in rat cortical neuron cultures. Neurosci Lett 2001; 297:33-6. [PMID: 11114478 DOI: 10.1016/s0304-3940(00)01661-x] [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: 10/18/2022]
Abstract
Hyperphosphorylation of tau is a characteristic feature of the neurodegenerative pathology in Alzheimer's disease (AD). Okadaic acid (OA) is currently used in models of AD research to increase the phosphorylation of tau. Using immunocytochemistry and fluorescent study, we found that markers of oxidative activity such as nitrotyrosine, c-jun, 2',7'-dichlorofluorescein diacetate (DCF), and heme oxygenase-1 (HO-1) were altered in OA-treated culture. Immunoreactivity of nitrotyrosine and c-jun, and DCF-oxidation were increased in degenerating neurons, while HO-1 expression was increased in astrocyte in response to OA. The data suggest that tau phosphorylation and oxidative damage be implicated in OA-induced neurodegeneration.
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1121
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1122
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Hwang BY, Kim HS, Lee JH, Hong YS, Ro JS, Lee KS, Lee JJ. Antioxidant benzoylated flavan-3-ol glycoside from Celastrus orbiculatus. JOURNAL OF NATURAL PRODUCTS 2001; 64:82-84. [PMID: 11170672 DOI: 10.1021/np000251l] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A new flavan-3-ol glycoside, (-)-epicatechin-5-O-beta-D-glucosyl-3-benzoate (1), and two known compounds, (-)-epicatechin and (-)-epiafzelechin, were isolated from an EtOAc extract of Celastrus orbiculatus aerial parts that exhibited significant antioxidant effect in a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical assay. The structure of 1 was elucidated by spectroscopic analyses, and compound 1 and its aglycon, (-)-epicatechin-3-benzoate (2), were found to be moderately active as antioxidants in the DPPH assay.
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1123
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Lee JH, Ko WS, Kim YH, Kang HS, Kim HD, Choi BT. Anti-inflammatory effect of the aqueous extract from Lonicera japonica flower is related to inhibition of NF-kappaB activation through reducing I-kappaBalpha degradation in rat liver. Int J Mol Med 2001; 7:79-83. [PMID: 11115613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
We investigated the anti-inflammatory effects of aqueous extract from Lonicera japonica flower (AELJ), a traditional skin rash drug, in lipopolysaccharide (LPS)-induced rat liver sepsis. Immunoblot analysis showed that the level of nuclear factor (NF)-kappaBp65 was rapidly up-regulated and inhibitory (I)-kappaBalpha was down-regulated by LPS challenge. However, AELJ inhibited the increase of NF-kappaBp65 and degradation of I-kappaBalpha in the liver of LPS-challenged rats. Immunohistochemical analysis of rat hepatocytes showed that LPS-induced inflammatory responses, involving degradation of I-kappaBalpha and induction of NF-kappaBp65, tumor necrosis factor (TNF)-alpha and inducible nitric oxide synthase (iNOS), are partially inhibited by pretreatment with AELJ. These results suggest that AELJ may act as a therapeutic agent for inflammatory disease through a selective regulation of NF-kappaB activation.
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Jeong DH, Lee SJ, Lee JH, Bae IH, Jeong KS, Jang JJ, Lim IK, Kim MR, Lee MJ, Lee YS. Subcellular redistribution of protein kinase C isozymes is associated with rat liver cirrhotic changes induced by carbon tetrachloride or thioacetamide. J Gastroenterol Hepatol 2001; 16:34-40. [PMID: 11206314 DOI: 10.1046/j.1440-1746.2001.02364.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIMS Protein kinase C (PKC) plays a key role in the alteration of signal transduction in the liver, which may contribute to the development of liver cirrhosis. The aim of the present study was to examine the subcellular redistribution of PKC isozymes in rat liver cirrhosis, which is induced by two different cirrhotic chemical agents, carbon tetrachloride (CCl4) and thioacetamide (TAA). METHODS AND RESULTS Thioacetamide and CCl4 were administered to rats for 8 and 30 weeks, respectively before rats were killed and autopsies performed at 9, 20 and 30 weeks later. The TAA induced a fibrotic pattern in the liver that differed from that produced by CCl4, notably in the formation of fibrous connective tissue and the proliferation of bile ductule cells. Cholangiofibrosis and clear-cell foci were also observed in TAA-treated rats at 30 weeks. Histological examination revealed that severe cirrhotic changes were present 9 weeks after the commencement of CCl4 treatment and 30 weeks after TAA treatment. DISCUSSION When the subcellular redistribution of PKC isozymes (PKCalpha, -beta1, -delta, and -epsilon) was examined, all the PKC isozymes in CCl4-treated rats were found to be translocated to the membrane fraction, which may mean PKC activation, and then downregulated by proteolytic degradation after 9 weeks of treatment, which coincided with peak cirrhotic changes. All rats treated with CCl4 recovered to the control level after 20 weeks of treatment. In the case of TAA-treated rats, PKC isozymes were translocated to the particulate fraction of the liver after 9 weeks of treatment and this persisted in most of the rats for the duration of the experiment. CONCLUSIONS From these results, it would appear that PKC translocation preceded morphologic changes, and that an altered subcellular distribution of the PKC isozyme may be associated with the response to liver damage and carcinogenesis.
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1125
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Lee JH, Ko WS, Kim YH, Kang HS, Kim HD, Choi BT. Anti-inflammatory effect of the aqueous extract from Lonicera japonica flower is related to inhibition of NF-kappaB activation through reducing I-kappaBalpha degradation in rat liver. Int J Mol Med 2001. [DOI: 10.3892/ijmm.7.1.79] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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