601
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Lee HS, Park KL, Choi SU, Lee CO, Jung SH. Effect of substituents on benzenesulfonyl motif of 4-phenyl-1-arylsulfonylimidazolidinones for their cytotoxicity. Arch Pharm Res 2000; 23:579-84. [PMID: 11156178 DOI: 10.1007/bf02975244] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To explore the effect of substituents' on phenyl motif on sulfonyl function of novel anticancer 4-phenyl-1-benzenesulfonylimidazolidinones (1), electron donating or withdrawing substituents were introduced at 3 or 4-position and the analogs were tested against human lung (A549) and colon (HCT-15) cancer cell lines. Quantitative structure activity relationship of the 4-substituted series shows that only STERIMOL L values are well correlated. The increment of substituent's volume enhances the activity against both cell lines. The small substituent at 3-position additionally increases the activity. However naphthyl group in place of phenyl reduces the activity. Therefore the phenyl motif with sterically large substituent at 4-position and small substituent at 3-position may be important for their activity. Integration of these substituents' effects into the structural design led to discover the more potent analog, 4-phenyl-1-(N-acetylindoline-5-sulfonyl) imidazolidinone (1n).
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602
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Yoon YS, Shin JW, Park CB, Oh YS, Lee IS, Lee HS, Lee JS. Morphological structure of accessory spleen in Chinese hamsters. J Vet Sci 2000; 1:73-5. [PMID: 14614300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Abstract
To attempt a rigorous definition of the structure of the accessory spleen (AS) in the Chinese hamster, we examined twenty-one animals, and found AS in 5 animals (23.8%), which were over 7-month-old. The AS had no connection with the main spleen and was seen as a dark red oval organ (0.7 mm x 1.5 mm), which was embedded in the adipose tissue near the tail of the pancreas. It was demarcated from the adipose tissue and some pancreatic tissue. The organ was encapsulated by thin collagenous connective tissue and smooth muscle fibers, and contained lymphatic nodules, reticular fibers, nodular central arterioles, macrophages and megakaryocytes. Notably the incidence of AS appeared to increase with age in the Chinese hamsters.
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603
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Lee HS, Lee HY, Gu HK, Han SS, Yun CH, Kim JH, Kim JA, Lee ES, Nam DH, Jeong TC. Effects of flupyrazofos on liver microsomal cytochrome P450 in the male Fischer 344 rat. Xenobiotica 2000; 30:1123-30. [PMID: 11307969 DOI: 10.1080/00498250010013917] [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: 10/16/2022]
Abstract
1. The effects of flupyrazofos on liver microsomal cytochrome P450 were investigated in the male Fischer 344 rat. When rats were treated intraperitoneally with flupyrazofos for 3 consecutive days, the activities of ethoxyresorufin O-deethylase and testosterone 2 beta-hydroxylase were significantly reduced, whereas the activities of pentoxyresorufin beta-depentylase and testosterone 6beta- and 7 alpha-hydroxylases were induced in liver microsomes. 2. Within 24 h after treatment with 50 m kg(-1) flupyrazofos, most enzyme activities were decreased, indicating the interaction of flupyrazofos with cytochrome P450. 3. In Western immunoblotting, cytochrome P4502B1/2 proteins were clearly induced by treatment with flupyrazofos, whereas P4501A1/2 and 2C6 proteins were reduced in liver microsomes. 4. The present results indicate that flupyrazofos modulates the expression of cytochrome P450 in rat.
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604
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Park KU, Lee HS, Kim CJ, Kim EC. Fungal discitis due to Aspergillus terreus in a patient with acute lymphoblastic leukemia. J Korean Med Sci 2000; 15:704-7. [PMID: 11194199 PMCID: PMC3054694 DOI: 10.3346/jkms.2000.15.6.704] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [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
We report a case of Aspergillus terreus discitis which developed in a patient with acute lymphoblastic leukemia following induction chemotherapy. A. terreus was isolated from sputum, one month earlier, but the physician did not consider it significant at the time. Magnetic resonance imaging study showed the involvement of L3-4, L4-5 and L5-S1 intervertebral discs. Etiology was established by means of histology and culturing a surgical specimen of disc materials. Our patient survived after a surgical debridement and amphotericin B administration with a total dose of 2.0 g. Discitis caused by Aspergillus terreus is a very rare event. A. terreus is one of the invasive Aspergillus species. The pathogenetic mechanism is discussed and the literature is reviewed.
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605
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Kang JL, Pack IS, Hong SM, Lee HS, Castranova V. Silica induces nuclear factor-kappa B activation through tyrosine phosphorylation of I kappa B-alpha in RAW264.7 macrophages. Toxicol Appl Pharmacol 2000; 169:59-65. [PMID: 11076697 DOI: 10.1006/taap.2000.9039] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It was previously reported that protein tyrosine kinase (PTK) but not protein kinase C or A plays an important role in silica-induced activation of NF-kappa B in macrophages. The question is raised whether PTK stimulation and NF-kappa B activation in silica-stimulated macrophages are directly connected through tyrosine phosphorylation of I kappa B-alpha. Results indicate that stimulation of macrophages with silica led to NF-kappaB activation through tyrosine phosphorylation without serine phosphorylation. Specific inhibitors of protein tyrosine kinase, such as genistein and tyrophostin AG126, prevented tyrosine phosphorylation of I kappa B-alpha in response to silica. I kappa B-alpha protein levels remained relatively unchanged for up to 60 min after silica stimulation. Moreover, inhibition of proteasome proteolytic activity did not affect NF-kappa B activation by silica. Antioxidants, such as superoxide dismutase (SOD), N-acetylcysteine (NAC), and pyrrolidine dithiocarbamate (PDTC), blocked tyrosine phosphorylation of I kappa B-alpha induced by silica, suggesting reactive oxygen species (ROS) may be important regulatory molecules in NF-kappa B activation through tyrosine phosphorylation of I kappa B-alpha. The results suggest that tyrosine phosphorylation of I kappa B-alpha represents a proteasome proteolytic activity-independent mechanism for NF-kappa B activation that directly couples NF-kappa B to cellular tyrosine kinase in silica-stimulated macrophages. This proposed mechanism of NF-kappa B activation induced by silica could be used as a target for development of antiinflammatory and antifibrosis drugs.
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606
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Abstract
In paternity test using the DNA evidence, the analysis of the deficient case that the DNA profiles of mother or alleged father are not available is different from that of the trio case analyzed routinely. However, the motherless case that the genotypes of mother is not available has been requested and analyzed like the trio case. In this paper, we compared the motherless case and the trio case through the mean exclusion chance describing the probability of exclusion for a genetic marker system and the distribution of the probability of paternity calculated using the three current methods. We have also shown a case which can be falsely discriminated if it were requested in the analysis of the motherless case, and conclude that the analysis of the motherless case should be carefully conducted and the level for the discrimination should be different from that of the trio case.
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607
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Lee JH, Kim JH, Hwang SW, Lee WJ, Yoon HK, Lee HS, Hong SS. High-level expression of antimicrobial peptide mediated by a fusion partner reinforcing formation of inclusion bodies. Biochem Biophys Res Commun 2000; 277:575-80. [PMID: 11061996 DOI: 10.1006/bbrc.2000.3712] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A gene expression system for antimicrobial peptides, which could be effectively used for various studies or applications of the antimicrobial peptides, has been developed. To avoid the harmful effects on an expression host, Escherichia coli, the antimicrobial peptides were expressed as fusion proteins with a polypeptide F4, which is a truncated PurF fragment that highly tends to form inclusion bodies. Seven different kinds of antimicrobial peptides have been successfully expressed by this expression system and the resulting expression level of fusion proteins reached up to 30% of total cell proteins. To confirm the identity of the recombinant peptide, MSI-344 was selected as a model peptide and purified to homogeneity, and we could obtain the recombinant MSI-344 of a high purity and with a good yield, which was identical to the authentic peptide in the aspects of the chemical and antimicrobial properties. These results show that the neutral fusion partner, which reinforces the formation of inclusion bodies, could mediate a high-level expression of the antimicrobial peptides.
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608
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Kim J, Lee S, Lee HS, Lee B. Cross talk in holographic memories with lensless phase-conjugate holograms. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2000; 17:2056-2060. [PMID: 11059602 DOI: 10.1364/josaa.17.002056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Recently holographic memory with lensless phase-conjugate holograms has attracted much attention because it opens up the possibility of compact holographic memories. We investigate cross-talk noise in compact holographic memories with angular multiplexing. It turns out that the optimum angular separation is the same as that for the Fourier plane hologram in the leading order and that the noise-to-signal ratio is independent of the positions in the output plane, similar to the case of the image plane hologram.
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609
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Kim YA, Lee HS, Park YC, Lee YT. A convenient method for oxidation of organophosphorus pesticides in organic solvents. ENVIRONMENTAL RESEARCH 2000; 84:303-309. [PMID: 11097804 DOI: 10.1006/enrs.2000.4099] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Since organophosphorus pesticides can be oxidized to oxons in vivo and in the environment and their determination based on inhibition of cholinesterases can be more sensitive after their oxidation to oxons, development of an efficient method for their in vitro oxidation is important for their toxicological and analytical studies. This study demonstrated that treatment of organophosphorus pesticides with 10 molar excess bromine in acetonitrile is a rapid and efficient method for their oxidation. For the nine organophosphorus pesticides tested, the reaction was complete within a few seconds. All reactions gave the respective oxons as single major product, except that of fenthion, which gave two major products, the respective oxon and another product from further oxidation of the oxon. The yields of the oxons were 82-100%. The inhibitory power of the pesticides on acetylcholinesterase before and after oxidation was measured and, for all pesticides tested, the power after oxidation was much higher than that before oxidation. Inhibition calibration curves for both unoxidized and oxidized forms of fenitrothion and parathion were obtained. The sensitivity of the detection of these pesticides was much higher after oxidation.
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610
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Suh DH, Lee HS, Kim SD, Cho KH, Kim KH, Park KC. Coexistence of disseminated superficial porokeratosis in childhood with congenital linear porokeratosis. Pediatr Dermatol 2000; 17:466-8. [PMID: 11123781 DOI: 10.1046/j.1525-1470.2000.01823.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Porokeratosis is a genodermatosis characterized by abnormal epidermal keratinization with the histologic finding of cornoid lamella. To date, five clinical variants have been identified. However, the coexistence of these variants in a single patient has been described only rarely. We report a 5-year-old girl with the simultaneous occurrence of porokeratotic lesions in linear and disseminated patterns. Linear lesions were detected at birth and the disseminated lesions developed at the age of 3 years. Histologically the lesions had cornoid lamella, which is typical of this condition.
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611
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Pae HO, Seo WG, Oh GS, Shin MK, Lee HS, Lee HS, Kim SB, Chung HT. Potentiation of tumor necrosis factor-alpha-induced apoptosis by mistletoe lectin. Immunopharmacol Immunotoxicol 2000; 22:697-709. [PMID: 11105782 DOI: 10.3109/08923970009016433] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Mistletoe lectins (MLs) constitute the active principle in extract preparations from mistletoe, commonly used as immunomodulator in adjuvant tumor therapy. MLs, classified as type II ribosome inactivating proteins, inhibit protein synthesis. Inhibitors of protein synthesis may modify cancer cell response to tumor necrosis factor-alpha (TNF). In the present study, we have hypothesized that the anticancer efficacy of TNF may be potentiated by MLs. In deed, simultaneous treatment of human cervix carcinoma HeLa or breast carcinoma MCF-7 cells with MLs isolated from European or Korean mistletoe rendered them more sensitive to induction of apoptosis by TNF. The mechanism by which MLs amplify the effect of TNF may involve suppression of the survival protein synthesis.
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612
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Abstract
Aspirin is a widely used drug and perceived by most physicians to be inexpensive. High rates of concurrent gastroprotective agents are reported from a study of cardiology outpatients. Aspirin takers are more likely to also be taking a proton pump inhibitor, H(2) antagonist, or antacid than non-aspirin takers. They are more than 10 times as likely to be experiencing upper gastrointestinal symptoms. Although aspirin is inexpensive, it is emphasised that the overall cost implications for therapy can be significant and it is suggested that it may be more appropriate to consider the use of alternative antiplatelet agents in patients who tolerate aspirin poorly.
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613
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Lin RY, Curry A, Pesola GR, Knight RJ, Lee HS, Bakalchuk L, Tenenbaum C, Westfal RE. Improved outcomes in patients with acute allergic syndromes who are treated with combined H1 and H2 antagonists. Ann Emerg Med 2000; 36:462-8. [PMID: 11054200 DOI: 10.1067/mem.2000.109445] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
STUDY OBJECTIVE Although the addition of H(2) blockers to H(1) antagonists has been promoted for use in anaphylaxis, there have been no large studies establishing the advantage of this approach in treating acute allergic syndromes. In this study we tested the hypothesis that combined H(1) and H(2) blockage results in improved outcomes in patients treated for acute allergic syndromes compared with treatment with H(1) blockade alone. METHODS In a randomized, double-blind, placebo-controlled trial, 91 adult patients with acute allergic syndromes were treated with either 50 mg of diphenhydramine and saline solution (control group) or with 50 mg of diphenhydramine and 50 mg of ranitidine (active group). These patients were treated with parenteral administration. Patients were recruited from an emergency department at an urban academic medical center. The primary endpoints were resolution of urticaria, angioedema, or erythema at 2 hours after protocol treatment. Areas of cutaneous involvement, heart rates, blood pressures, respiratory findings, and symptom scores were also assessed at baseline, 1 hour, and 2 hours. RESULTS There were significantly more patients without urticaria at 2 hours among the patients in the active group compared with those in the control group. Both groups had similar proportions of urticaria at baseline. Logistic regression models to predict resolution of urticaria, which accounted for baseline urticarial involvement, showed odds ratios in favor of the active group treatment. Similar findings were observed when the absence of both urticaria and angioedema was considered as the dependent variable. There was not a significant difference between the 2 groups with regard to the absence of erythema or angioedema (irrespective of the presence of urticaria) at 2 hours. Blood pressure and symptoms did not show differences between the 2 groups over time. Lower heart rates were observed 1 hour after treatment in the active treatment group (mean reduction 10 beats/min) compared with those found in the placebo group (mean reduction 6 beats/min). CONCLUSION These data show that adding H(2) blockers to H(1) antagonists results in additional improvement of certain cutaneous outcomes for patients presenting with acute allergic syndromes. These findings favor the recommendation for using combined H(1) and H(2) antihistamines in acute allergic syndromes.
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614
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Lim DS, Kim YH, Lee HS, Park CG, Seo HS, Shim WJ, Oh DJ, Ro YM. Coronary flow reserve is reflective of myocardial perfusion status in acute anterior myocardial infarction. Catheter Cardiovasc Interv 2000; 51:281-6. [PMID: 11066106 DOI: 10.1002/1522-726x(200011)51:3<281::aid-ccd7>3.0.co;2-o] [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: 11/11/2022]
Abstract
Our objective was to determine whether coronary vasodilatory reserve (CVR) correlates with the perfusion state of infarct zone in early recovery phase of acute anterior myocardial infarction (AMI). We studied 14 patients (11 males; mean age, 46 years) who had AMI and 6 control subjects who had chest pain but normal coronary angiograms. All patients underwent successful percutaneous revascularization of left anterior descending (LAD) coronary artery. Coronary flow velocity was measured using intracoronary (IC) Doppler at baseline and following IC injection of 18 microg of adenosine. Myocardial perfusion was evaluated by myocardial contrast echocardiography (MCE). CVR was higher in patients without a perfusion defect on MCE than in those with (2.48 +/- 0.21 vs. 1.66 +/- 0.13, P = 0.001). Subjects with a perfusion defect had a lower CVR than controls (1.66 +/- 0.13 vs.2.40 +/- 0.18, P < 0.05). CVR was > 2.0 in all subjects without a perfusion defect. There was a strong correlation between the magnitude of myocardial opacification in the LAD territory and CVR (r = 0.80, P < 0.01). Increase in peak diastolic flow velocity after adenosine infusion, but not systolic flow velocity, correlated with myocardial opacification index (r = 0.63, P = 0.016). CVR of infarct-related artery correlated closely with the perfusion status of the myocardium in infarct zone and those with a CVR > 2.0 had normal myocardial perfusion. These data suggest that CVR may be used to determine the perfusion state of the myocardium in the infarct zone, which is a known predictor of myocardial viability. Cathet. Cardiovasc. Intervent. 51:281-286, 2000.
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615
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Mun JH, Yu HJ, Lee HS, Kwon YM, Lee JS, Lee I, Kim SG. Two closely related cDNAs encoding actin-depolymerizing factors of petunia are mainly expressed in vegetative tissues. Gene 2000; 257:167-76. [PMID: 11080583 DOI: 10.1016/s0378-1119(00)00412-1] [Citation(s) in RCA: 22] [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
Actin-depolymerizing factor (ADF) is one of the small actin-binding proteins that regulate actin dynamics in cells. We have isolated two cDNA clones, PhADF1 and PhADF2, encoding ADF from cDNA libraries constructed from petal protoplast cultures and flowers of Petunia hybrida. PhADF1 and PhADF2 encode polypeptides of 139 and 143 amino acids with a calculated molecular mass of 16.04 and 16.51kDa, respectively. Co-sedimentation assay showed that the recombinant PhADF1 protein produced in Escherichia coli binds to F-actin at pH7. 0 and preferentially depolymerizes it at pH8.0. Gene tree analysis indicates that the plant ADF family can be grouped into four classes, and PhADFs are included in class I. Southern blot analyses revealed that one or two copies of PhADF genes are present in petunia genome, and several other related isoforms also exist. Northern blot analyses indicated that PhADF1 and PhADF2 are closely related and abundantly expressed in every plant organ except pollen. In addition, they are highly accumulated in mature vegetative tissue (petal, leaf, and stem). Our results indicate that the transcription of petunia ADF genes is differentially regulated by developmental signals.
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MESH Headings
- Actin Depolymerizing Factors
- Amino Acid Sequence
- Blotting, Northern
- Blotting, Southern
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Plant/genetics
- Destrin
- Gene Dosage
- Gene Expression Regulation, Plant
- Microfilament Proteins/genetics
- Molecular Sequence Data
- Phylogeny
- Plant Proteins/genetics
- Protein Isoforms/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Solanaceae/cytology
- Solanaceae/genetics
- Tissue Distribution
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616
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Kang JL, Pack IS, Lee HS, Castranova V. Enhancement of nuclear factor-kappaB activation and protein tyrosine phosphorylation by a tyrosine phosphatase inhibitor, pervanadate, involves reactive oxygen species in silica-stimulated macrophages. Toxicology 2000; 151:81-9. [PMID: 11074303 DOI: 10.1016/s0300-483x(00)00295-x] [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: 11/25/2022]
Abstract
Reactive oxygen species (ROS) and phosphorylation events mediated by tyrosine kinase are involved in silica-induced nuclear factor-kappa B (NF-kappaB) activation. Protein tyrosine phosphatase (PTPase) acts to limit protein tyrosine phosphorylation. In the present study, we investigated the role of PTPase in NF-kappaB activation and tyrosine phosphorylation in silica-stimulated macrophages, and the involvement of ROS in these responses. Treatment of mouse peritoneal macrophages (RAW264.7 cells) with a PTPase inhibitor, pervanadate, markedly enhanced the DNA-binding activity of NF-kappaB in the presence or absence of silica. The stimulatory effect of pervanadate on NF-kappaB activation was also demonstrated in LPS-stimulated macrophages. A specific inhibitor of protein tyrosine kinase (PTK), genistein, prevented the NF-kappaB activation induced by pervanadate in the presence of silica while inhibitors of protein kinase A or C, such as staurosporine or H7, had no inhibitory effect on NF-kappaB activation. A variety of antioxidants, such as catalase, superoxide dismutase, N-acetyl cysteine (NAC), and pyrrolidine dithiocarbamate, inhibited NF-kappaB activation induced by pervanadate in the presence of silica. Furthermore, pervanadate markedly enhanced silica- or LPS-induced protein tyrosine phosphorylation in cells. Treatment of macrophages with NAC abolished the increase in tyrosine phosphorylation in cells stimulated with the combination of pervanadate and either silica or LPS or with silica alone. The results suggest that PTPase may play a crucial role in the negative regulation of silica-signaling pathways leading to NF-kappaB activation in macrophages. Furthermore, ROS appear to be involved in downstream signaling between PTPase inhibition and NF-kappaB activation.
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617
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Lee HS, Huang AM, Huang GT, Yang PM, Chen PJ, Sheu JC, Lai MY, Lee SC, Chou CK, Chen DS. Hepatocyte growth factor stimulates the growth and activates mitogen-activated protein kinase in human hepatoma cells. J Biomed Sci 2000; 5:180-4. [PMID: 9678488 DOI: 10.1007/bf02253467] [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: 11/25/2022] Open
Abstract
Hepatocyte growth factor (HGF) is a potent mitogen for hepatocytes and various epithelial cells. Unexpectedly, it has been reported to inhibit the growth of hepatoma cells in vitro. To clarify this phenomenon, we examined the effects of recombinant baculovirus-expressed HGF on the growth of 6 human hepatoma cell lines. The growth of Hep3B and HepG2 cells was markedly stimulated to 1.8- and 1.7-fold, respectively, PLC/PRF/5 to 1.4-fold, and SK-Hep-1 to 1.2-fold in a dose-dependent manner under HGF concentrations below 20 ng/ml. Neither HuH-7 nor HCC36 were affected. None of these cells were inhibited. All these cells expressed c-Met, the membrane receptor for HGF, and their c-Met would be activated to be phosphorylated upon addition of HGF. They also contained the ERK2 subgroup of mitogen-activated protein kinases (MAPKs). When HGF was added, their ERK2 would also be phosphorylated. The extent of ERK2 phosphorylation was partially correlated to their growth response to HGF. In conclusion, HGF could stimulate the growth of certain human hepatoma cells, probably through activation of c-Met and MAPKs.
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618
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Kim NY, Pae HO, Kim YC, Choi CK, Rim JS, Lee HS, Kim YM, Chung HT. Pentoxifylline potentiates nitric oxide production in interleukin-1beta-stimulated vascular smooth muscle cells through cyclic AMP-dependent protein kinase A pathway. GENERAL PHARMACOLOGY 2000; 35:205-11. [PMID: 11827727 DOI: 10.1016/s0306-3623(01)00108-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the present study, we observed that pentoxifylline (PTX) significantly augmented the nitric oxide (NO) production and the iNOS gene expression by interleukin-1beta (IL-1beta)-stimulated vascular smooth muscle cells (VSMCs). The enhancing effects of PTX on the IL-1beta-induced NO production was associated with an increased intracellular cyclic AMP (cAMP) levels, and the synergistic effects of PTX on the IL-1beta-induced NO production was blocked by cAMP-dependent protein kinase A (PKA) inhibitors. PKA inhibitors, KT5720 and H89, markedly decreased the augmented expression of iNOS gene whereas ODQ, a soluble guanylate cyclase inhibitor, did not affect the enhancing effect. In addition, the pretreatment with KT5720 or H89 abolished the increased translocation of the p65 subunit of NF-kappaB into the nucleus by PTX in the IL-1beta-stimulated VSMCs. These results suggest that enhancing effects of PTX on the iNOS gene expression in the IL-1beta-stimulated VSMCs is mediated predominantly through the activation of NF-kappaB via cAMP-dependent PKA pathway.
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619
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Jung N, Yi YW, Kim D, Shong M, Hong SS, Lee HS, Bae I. Regulation of Gadd45gamma expression by C/EBP. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:6180-7. [PMID: 11012671 DOI: 10.1046/j.1432-1327.2000.01692.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Gadd45gamma (growth arrest and DNA damage-inducible) gene is activated transcriptionally by at least two kinds of agents: DNA damaging agent such as methyl methanesulfonate (MMS) and UV radiation, or cytokines such as interleukin (IL)-6, IL-2 and granulocyte colony-stimulating factor (G-CSF). To investigate the sequences and transcription factors involved in induction of Gadd45gamma after treatment with IL-6, the human gene was cloned and sequenced. We found C/EBP (CCAAT/enhancer-binding protein) family proteins, major transcription factors in the IL-6 signal transduction pathway, could regulate the transcriptional activity of the Gadd45gamma promoter. In addition, a noncanonical C/EBP-binding site within the Gadd45gamma promoter where C/EBPbeta and C/EBPdelta could bind, was identified by electrophoretic mobility shift assay (EMSA) and reporter gene analysis. Furthermore, we found a coordinated expression profile between Gadd45gamma mRNA and C/EBPs (beta and delta) protein during the differentiation of M1 cells: the amount of Gadd45gamma transcripts became maximal when both C/EBPbeta and C/EBPdelta levels were high, on day 1 of differentiation of M1 cells after treatment with IL-6. These findings suggest that mitotic growth arrest coupled to M1 cell differentiation is mediated by C/EBPs stimulation of growth arrest-associated genes such as Gadd45gamma.
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620
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Lee HS, Jeong CK, Choi SJ, Kim SB, Lee MH, Ko GI, Sohn DH. Simultaneous determination of aceclofenac and diclofenac in human plasma by narrowbore HPLC using column-switching. J Pharm Biomed Anal 2000; 23:775-81. [PMID: 11022903 DOI: 10.1016/s0731-7085(00)00381-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A fully automated narrowbore high performance liquid chromatography (HPLC) with column-switching was developed for the simultaneous determination of aceclofenac and diclofenac from human plasma samples. Plasma sample (100 microl) was directly introduced onto a Capcell Pak MF Ph-1 column (20 x 4 mm I.D.) where primary separation was occurred to remove proteins and concentrate target substances using acetonitrile potassium phosphate (pH 7, 0.1 M) (14:86, v/v). The drug molecules eluted from MF Ph-1 column were focused in an intermediate column (35 x 2 mm I.D.) by the valve switching step. The substances enriched in intermediate column were eluted and separated on the narrowbore phenyl hexyl column (100 x 2 mm I.D.) using acetonitrile-potassium phosphate (pH 7, 0.02M) (33:67, v/v) when the valve status was switched back to A position. The method showed excellent sensitivity (detection limit of 10 ng ml(-1)) with small volume of samples (100 microl), good precision and accuracy, and speed (total analysis time 17 min) without any loss in chromatographic efficiency. The response was linear (r2 > or = 0.999) over the concentration range of 50-10,000 ng ml(-1).
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621
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Abstract
Achondrogenesis is a lethal form of congenital chondrodystrophy characterized by extreme micromelia. We describe a case of achondrogenesis type II (Langer-Saldino achondrogenesis) detected by prenatal ultrasonography at 20-week gestation. A dwarfed fetus with large head, short neck and chest, prominent abdomen and short limbs was terminated transvaginally. Radiologic and histopathologic examination revealed features of mild form of achondrogenesis type II. Although the case had no known risk factor and the phenotypic abnormality was mild, modern development in prenatal screening made the early detection possible.
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622
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Yoo CW, Kim MK, Lee HS. Predictors of renal outcome in diffuse proliferative lupus nephropathy: data from repeat renal biopsy. Nephrol Dial Transplant 2000; 15:1604-8. [PMID: 11007829 DOI: 10.1093/ndt/15.10.1604] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Diffuse proliferative lupus nephropathy (DPLN) is the most frequent and severe form of renal disease in patients with systemic lupus erythaematosus. Histological parameters at the initial biopsy of patients with DPLN that would predict the progression of renal pathology or function at the second biopsy are not clearly defined. METHODS The prognostic significance of renal histological indices, such as glomerular activity index and volume density of cortical interstitium [Vv(int/cortex)], was evaluated from successive renal biopsies in 21 patients with DPLN. RESULTS At the time of the second biopsies, performed an average of 43 months after the first biopsies, seven patients (33%) showed progressive renal insufficiency. Only three cases (14%) transformed to World Health Organization class I or III. The seven patients with clinical progression exhibited a higher frequency of hypertension, higher percent glomerulosclerosis, and larger Vv(int/cortex) at the time of second biopsy as compared with the 14 patients without renal insufficiency. At the first biopsy, patients with clinical progression showed a higher glomerular activity index (2.9+/-1.2 vs 1.3+/-0.8, P<0.05) and larger Vv(int/cortex) (0.13+/-0.07 microm(3)/microm(3) vs 0.05+/-0.03 microm(3)/microm(3), P<0.05) than the patients without progression. The glomerular activity index at the first biopsy correlated directly with per cent glomerulosclerosis, Vv(int/cortex), and serum creatinine level at the second biopsy. Vv(int/cortex) in the first biopsy also showed a significant relation with per cent glomerulosclerosis and serum creatinine level at the second biopsy. CONCLUSIONS These results suggest that higher glomerular activity and larger interstitial volume density at the initial biopsy can predict future progression of renal pathology or function in DPLN.
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623
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Park CJ, Park CB, Hong SS, Lee HS, Lee SY, Kim SC. Characterization and cDNA cloning of two glycine- and histidine-rich antimicrobial peptides from the roots of shepherd's purse, Capsella bursa-pastoris. PLANT MOLECULAR BIOLOGY 2000; 44:187-97. [PMID: 11117262 DOI: 10.1023/a:1006431320677] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two novel antimicrobial peptides were isolated and characterized from the roots of shepherd's purse, Capsella bursa-pastoris. These antimicrobial peptides, named shepherin I and shepherin II, consist of 28 and 38 amino acids, respectively, and are glycine- and histidine-rich peptides. Shepherin I and shepherin II have 67.9% and 65.8% (mol/mol) glycine, respectively, and 28.6% and 21.1% (mol/mol) histidine, respectively. Both shepherins have a Gly-Gly-His motif. These antimicrobial peptides exhibit antimicrobial activity against Gram-negative bacteria and fungi. Circular dichroism spectra of shepherin I and shepherin II showed that shepherin I and shepherin II in 50% trifluoroethanol have 66.7% and 75% random coils, respectively, without any alpha-helices. cDNA sequence analysis revealed that shepherin I and shepherin II are produced from a single polypeptide, designated shep-GRP, consisting of 120 amino acids; shep-GRP has five distinct domains, an amino-terminal putative signal peptide, a shepherin I, a linker dipeptide, a shepherin II and a carboxy-terminal peptide. Southern blot analysis indicates that the gene encoding shepherins belongs to a low-complexity gene family. Northern blot analysis revealed that transcripts of shep-GRP are present in roots but not in leaves and stems.
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MESH Headings
- Amino Acid Sequence
- Anti-Bacterial Agents/chemistry
- Anti-Bacterial Agents/isolation & purification
- Anti-Bacterial Agents/pharmacology
- Bacteria/drug effects
- Bacteria/growth & development
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Brassicaceae/genetics
- Cell Division/drug effects
- Circular Dichroism
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Plant/genetics
- Fungi/drug effects
- Fungi/growth & development
- Gene Expression Regulation, Plant
- Glycine/genetics
- Histidine/genetics
- Microbial Sensitivity Tests
- Molecular Sequence Data
- Peptides
- Plant Proteins/genetics
- Plant Proteins/pharmacology
- Plant Roots/genetics
- Protein Isoforms/genetics
- Protein Isoforms/pharmacology
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Analysis, Protein
- Sequence Homology, Amino Acid
- Tissue Distribution
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624
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Kwon JH, Chun JY, Lee HS, Cheon CI, Song ES, Min KH, Lee MS. Cloning of the histidine biosynthetic genes from Corynebacterium glutamicum: organization and analysis of the hisG and hisE genes. Can J Microbiol 2000; 46:848-55. [PMID: 11006846] [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]
Abstract
The physically linked hisG and hisE genes, encoding for ATP-phosphoribosyltransferase and phosphoribosyl-ATP-pyrophosphohydrolase were isolated from the Corynebacterium glutamicum gene library by complementation of Escherichia coli histidine auxotrophs. They are two of the nine genes that participate in the histidine biosynthetic pathway. Molecular genetics and sequencing analysis of the cloned 9-kb insert DNA showed that it carries the hisG and hisE genes. In combining this result with our previous report, we propose that all histidine biosynthetic genes are separated on the genome by three unlinked loci. The coding regions of the hisG and hisE genes are 279 and 87 amino acids in length with a predicted size of about 30 and 10 kDa, respectively. Computer analysis revealed that the amino acid sequences of the hisG and hisE gene products were similar to those of other bacteria.
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625
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Lee HS, Han DS, Choi SJ, Choi SW, Kim DS, Bai DH, Yu JH. Purification, characterization, and primary structure of a chitinase from Pseudomonas sp. YHS-A2. Appl Microbiol Biotechnol 2000; 54:397-405. [PMID: 11030578 DOI: 10.1007/s002530000408] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A chitinase gene (chiA) from Pseudomonas sp. YHS-A2 was cloned into Escherichia coli using pUC19. The nucleotide sequence determination revealed a single open reading frame of chiA comprised of 1902 nucleotide base pairs and 633 deduced amino acids with a molecular weight of 67,452 Da. Amino acid sequence alignment showed that ChiA contains two putative chitin-binding domains and a single catalytic domain. Two proline-threonine repeat regions, which are linkers between catalytic and substrate-binding domains in some cellulases and xylanases, were also found. From E. coli, ChiA was purified 12.8-fold relative to the periplasmic fraction. The Michaelis constant and maximum initial velocity for p-nitrophenyl-N,N'-diacetylchitobiose were 1.06 mM and 44.4 micromol/h per mg protein, respectively. The purified ChiA binds not only to colloidal chitin but also to other substrates (avicel, chitosan, and xylan), but the binding affinity of avicel, chitosan, and xylan is around 10 times lower than that of colloidal chitin. The reaction of ChiA with colloidal chitin and chitooligosaccharides (trimer-hexamer) produced an end product of N,N'-diacetylchitobiose, indicating that ChiA is a chitobiosidase.
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