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Abstract
The locations of the 3' ends of RNAs in rat ribosome were studied by a fluorescence-labeling method combined with high hydrostatic pressure and agarose electrophoresis. Under physiological conditions, only the 3' ends of 28 S and 5.8 S RNA in 80 S ribosome could be labeled with a high sensitive fluorescent probe - fluorescein 5-thiosemicarbazide (FTSC), indicating that the 3' termini of 28 S and 5.8 S RNA were located on or near the surface of 80 S ribosome. The 3' terminus of 5 S RNA could be attacked by FTSC only in the case of the dissociation of the 80 S ribosome into two subunits induced by high salt concentration (1 M KCl) or at high hydrostatic pressure, showing that the 3' end of 5 S RNA was located on the interface of two subunits. However, no fluorescence-labeled 18 S RNA could be detected under all the conditions studied, suggesting that the 3' end of 18 S RNA was either located deeply inside ribosome or on the surface but protected by proteins. It was interesting to note that modifications of the 3' ends of ribosomal RNAs including oxidation with NaIO4, reduction with KBH4 and labeling with fluorescent probe did not destroy the translation activity of ribosome, indicating that the 3' ends of RNAs were not involved in the translation activity of ribosome.
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MESH Headings
- 3' Untranslated Regions/analysis
- Animals
- Cell-Free System/metabolism
- Electrophoresis, Agar Gel
- Fluorescent Dyes/chemistry
- Hydrostatic Pressure
- Kinetics
- Protein Biosynthesis
- RNA, Ribosomal/analysis
- RNA, Ribosomal, 18S/analysis
- RNA, Ribosomal, 18S/chemistry
- RNA, Ribosomal, 28S/analysis
- RNA, Ribosomal, 28S/chemistry
- RNA, Ribosomal, 5.8S/analysis
- RNA, Ribosomal, 5.8S/chemistry
- RNA, Ribosomal, 5S/analysis
- Rats
- Rats, Inbred Strains
- Ribosomes/chemistry
- Ribosomes/metabolism
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Tang S, He WJ, Xu H, Liu WY, Ruan KC. Eukaryotic elongation factor 2 can bind to the synthetic oligoribonucleotide that mimics sarcin/ricin domain of rat 28S ribosomal RNA. Mol Cell Biochem 2001; 223:117-21. [PMID: 11681712 DOI: 10.1023/a:1017914413081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Eukaryotic elongation factor 2 (eEF2) catalyzes the translocation of peptidyl-tRNA from the A site to P site by binding to the ribosome. In this work, the complex formation of rat liver eEF2 with a synthetic oligoribonucleotide (SRD RNA) that mimics sarcin/ricin domain of rat 28S ribosomal RNA is invested in vitro. Purified eEF2 can specifically bind SRD RNA to form a stable complex. tRNA competes with SRD RNA in binding to eEF2 in a less extent. Pretreatment of eEF2 with GDP or ADP-ribosylation of eEF2 by diphtheria toxin can obviously reduce the ability of eEF2 to form the complex with the synthetic oligoribonucleotide. These results indicate that eEF2 is likely to bind directly to the sarcin/ricin domain of 28S ribosomal RNA in the process of protein synthesis.
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53
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Tang S, Xie L, Hou F, Liu WY, Ruan K. Non-specific deadenylation and deguanylation of naked RNA catalyzed by ricin under acidic condition. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1519:192-8. [PMID: 11418185 DOI: 10.1016/s0167-4781(01)00236-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ricin A-chain catalyzes the hydrolysis of the N-glycosidic bond of a conserved adenosine residue at position 4324 in the sarcin/ricin domain of 28S RNA of rat ribosome. The GAGA tetraloop closed by C-G pairs is required for recognition of the cleavage site on 28S ribosomal RNA by ricin A-chain. In this study, ricin A-chain (reduced ricin) exhibits specific depurination on a synthetic oligoribonucleotide (named SRD RNA) mimic of the sarcin/ricin domain of rat 28S ribosomal RNA under neutral and weak acidic conditions. Furthermore, the activity of intact ricin is also similar to that of ricin A-chain. However, under more acidic conditions, both enzymes lose their site specificity. The alteration in specificity of depurination is not dependent on the GAGA tetraloop of SRD RNA. A higher concentration of KCl inhibits the non-specific N-glycosidase activity much more than the specific activity of ricin A-chain. In addition, characterization of depurination sites by RNA sequencing reveals that under acidic conditions ricin A-chain can release not only adenines, but also guanines from SRD RNA or 5S ribosomal RNA. This is the first report of the non-specific deadenylation and deguanylation activity of ricin A-chain to the naked RNA under acidic conditions.
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54
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Hu TZ, Wu XD, Liu WY. [Biliary tract reconstruction after cystectomy of congenital choledochal cyst]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2001; 15:165-7. [PMID: 11393959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE To evaluate the operative methods of biliary tract reconstruction after cystectomy of congenital choledochal cyst(CCC). METHODS One hundred and six cases with CCC underwent cystectomy and biliary tract reconstruction in our hospital from July 1984 to December 1999 were followed up. Among them, there were three kinds of procedures in biliary tract reconstruction: with single Roux-Y hepaticojejunostomy in 48 cases, with intussusceptive valve to the line of Roux-Y hepaticojejunostomy in 37 cases, with rectangular valve to the line of Roux-Y hepaticojejunostomy in 21 cases. RESULTS Fifty nine cases were followed up for 4.68 years in average. There were 3 cases with ascending cholangitis after single Roux-Y hepaticojejunostomy. And the symptom disappeared in 2 cases underwent reoperation with an intussueceptive valve plasty to the line of Roux-Y hepaticojejunostomy. No patients suffered from ascending cholangitis in the precautionary valve plasty group. CONCLUSION It suggests that the postoperative ascending cholangitis can be prevented effectively if standard cystectomy and prophylactic intussusceptive valve added to the line of Roux-Y hepaticojejunostomy are carried out. The procedure should be performed as soon as possible providing the child is tolerable.
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Liu WY, Xu QH, Ma YX. SILICA GEL PROMOTED SOLVENT-FREE SYNTHESIS OF ARYLCARBINOLS AND FERROCENYLCARBINOLS. ORG PREP PROCED INT 2000. [DOI: 10.1080/00304940009355960] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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56
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Chen WS, Liu WY, Yang GJ, Zhang WD, Chu ZY, Chen HS, Qiao CZ. [Structural elucidation of a new tetrahydroxystilbene of Radix Polygoni Multiflori Preparata and study on its cardiovascular activity]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 2000; 35:906-8. [PMID: 12567912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To investigate the cardiovascular active constituents of Radix Polygoni multiflori Preparata. METHODS Compounds were isolated from the water soluble extract with column chromatography of Sephadex, ODS and HPLC. The compounds were identified on the basis of spectral analysis (IR, EI-MS, FAB-MS, 1HNMR, 13CNMR, 2D-NMR) and phytochemical properties. Its inhibitory effect on the proliferation of bovine vascular smooth muscle cells were bioassayed in vitro. RESULTS One compound was isolated and identified as: 2,3,5,4'-tetrahydroxystilbene-2-O-(6"-O-alpha-D- glucopyranosyl)-beta-D-glucopyranoside. CONCLUSION Compound I is a new compound with cardiovascular activity.
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57
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Chang CI, Liu WY, Shyu CZ. Use of prawn blood agar hemolysis to screen for bacteria pathogenic to cultured tiger prawns Penaeus monodon. DISEASES OF AQUATIC ORGANISMS 2000; 43:153-157. [PMID: 11145455 DOI: 10.3354/dao043153] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A newly developed prawn blood agar consisting of 1 ml of tiger prawn hemolymph in medium containing 200 ppm Rose Bengal was used to determine the hemolytic activity of 35 isolates of bacteria obtained from cultured tiger prawns Penaeus monodon and their rearing water. For comparison, the hemolytic activity of these isolates was also determined in sheep blood agar. Nine isolates (25.7% of total) showed different hemolytic reactions on prawn blood agar and sheep blood agar. From the 35 isolates, 8 with various hemolytic characteristics were selected and the relationship between the type of hemolytic activity and pathogenicity was determined and compared. Four isolates that showed hemolytic activity in prawn blood agar caused high mortality to cultured tiger prawns. By contrast, a significantly lower mortality rate was observed for tiger prawns injected with 4 isolates that did not exhibit hemolytic activity on prawn blood agar. Results further showed that mortality did not correlate with hemolytic activity determined using sheep blood agar. Prawn blood agar containing P. monodon hemocytes was faster and more accurate for determining prawn hemolytic activity of bacterial isolates.
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58
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Pu Z, Li Y, Hou FJ, He F, Zhang N, Wu H, Liu WY. Structural studies of the glycopeptides of B-chain of cinnamomin--a type II ribosome-inactivating protein by nuclear magnetic resonance. Glycoconj J 2000; 17:749-59. [PMID: 11443276 DOI: 10.1023/a:1010957007038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Cinnamomin is a plant type II ribosome-inactivating protein (RIP) isolated from the seeds of Cinnamomum camphora. It consists of two nonidentical polypeptide chains (A- and B-chain) held together through one disulfide linkage. Its A- and B-chain contain 0.3% and 3.9% sugars respectively. The B-chain of cinnamomin was digested by pronase E and then the liberated glycopeptides were separated from non-glycopeptides by gel filtration chromatography on a Bio-Gel P-4 column. Three crude glycopeptides were obtained by continuing chromatography over anion-exchange resin (AG1-X2) in the buffer of 2% pyridine-acetic acid (pH 8.3) with a polygradient elution system. Through further purification by the gel filtration chromatography and HPLC, three major glycopeptides, GP1, GP2 and GP3 were obtained. Mainly by two-dimensional Nuclear Magnetic Resonance (NMR) including TOCSY, DQF-COSY, NOESY, HMQC and HMBC, their primary structures were analyzed as: Man\balpha1,3Man\balpha1,6(Man\balpha1,3)(Xyl\bbeta1,2)Man\bbeta1,4GlcNAc\bbeta1,4GlcNAc\bbeta1-(Gly-)Asn-Asn-Thr(GP1), Man\balpha1,6(Man\balpha1,3)(Xyl\bbeta1,2)Man\bbeta1,4GlcNAc\bbeta1,4(Fuc\balpha1,3)GlcNAc\bbeta1-Asn-Ala-Thr(GP2),Man\balpha1,6(Man\balpha1,3)Man\balpha1,6(Man\balpha 1,2 Man\balpha1,3)Man\bbeta1,4GlcNAc\bbeta1,4GlcNAc\bbeta1-(Ala-)Asn-Gly-Thr(GP3).
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59
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Zhang WD, Chen WS, Wang YH, Liu WY, Kong DY, Li HT. [Studies on flavone constituents of Erigeron breviscapus (Vant.) Hand.-Mazz]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2000; 25:536-8. [PMID: 12516462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To study the chemical constituents of Erigeron breviscapus. METHOD The constituents were separated and purified by column chromatography with silica gel, and identified by IR, MS, NMR and physical data. RESULT Five compounds were isolated and identified as 3, 5, 6, 4'-tetrahydroxy-7-methoxy flavonoid(I); 5, 7, 4'-trihydroxy flavonoid(II); 3, 5, 6, 7, 4'-pentahydroxy flavonoid(III); scutellarein (IV) and 5, 7, 4'-trihydroxy flavanone(V). CONCLUSION Compounds I, III and V were isolated from this plant for the first time.
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60
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Xu YX, Chen HS, Liang HQ, Gu ZB, Liu WY, Leung WN, Li TJ. Three new saponins from Tribulus terrestris. PLANTA MEDICA 2000; 66:545-550. [PMID: 10985082 DOI: 10.1055/s-2000-8609] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Three new steroidal saponins 1-3, together with five known steroidal saponins, L-mannitol and an inorganic salt were isolated from Tribulus terrestris L. (Zygophyllaceae). The structures of the new steroidal saponins were elucidated as hecogenin 3-O-beta-xylopyranosyl(1-->3)-beta-glucopyranosyl(1-->4)-beta-galactopyr anoside (1), hecogenin 3-O-beta-glucopyranosyl(1-->2)-beta-glucopyranosyl(1-->4)- beta-galactopyranoside (2) and 3-O-[beta-xylopyranosyl(1-->2)-[beta-xylopyranosyl(1-->3)]-beta- glucopyranosyl(1-->4)-[alpha-rhamnopyranosyl(1-->2)]-beta-galactopyranos yl]- 26-O-beta-glucopyranosyl-22-methoxy-(3 beta,5 alpha,25R)-furostan-3,26-diol (3). Structure elucidation was accomplished by 1D and 2D NMR spectra (13C-1H COSY, HMQC, HMBC, 1H-1H COSY, TOCSY, and NOESY), mass spectrometry (FABMS, ESIMS) and chemical methods.
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Tang S, Hu RG, Liu WY, Ruan KC. Non-specific depurination activity of saporin-S6, a ribosome-inactivating protein, under acidic conditions. Biol Chem 2000; 381:769-72. [PMID: 11030435 DOI: 10.1515/bc.2000.098] [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: 11/15/2022]
Abstract
Among five ribosome-inactivating proteins tested only saporin-S6 could efficiently release the adenine from adenosine 20 of the synthetic oligoribonucleotide (SRD RNA) mimic of the sarcin/ricin domain of rat 28S rRNA with a Km of 9 microM and a kcat of approximately 0.4 min(-1) at pH 7.6. The optimal pH for the depurination activity of saporin-S6 is 5.0. However, saporin-S6 lost its site-specificity of depurination on SRD RNA around the optimal pH. The non-specific depurination activity of saporin-S6 was dependent on the enzyme concentration and pH conditions. These results are valuable to understand the diversity and the depurination mechanism of ribosome-inactivating proteins.
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Hao JJ, Ye JQ, Yang Q, Gong ZZ, Liu WY, Wang ED. A silent antifungal protein (AFP)-like gene lacking two introns in the mould Trichoderma viride. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1475:119-24. [PMID: 10832025 DOI: 10.1016/s0304-4165(00)00047-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In cells of the mould Trichoderma viride, the existence of an antifungal protein (AFP)-like gene consisting of 285 bp was confirmed by Southern analysis that genomic DNA of T. viride could hybridize with the cDNA of mature AFP of Aspergillus giganteus MDH 18894. Except for the absence of two introns, the nucleotide sequence of the AFP-like gene was identical to that of the AFP gene of A. giganteus in positions 336-479, 568-649, and 706-765. The AFP-like gene could not be transcribed into its mRNA in T. viride cells as examined by RT-PCR using total RNAs of T. viride as template. Furthermore, AFP could not be detected either directly from the culture medium of T. viride or by Western analysis. However, the AFP-like gene could be actively expressed like the cDNA of AFP in Escherichia coli cell. Recombinant AFP exhibited similar antifungal activity as native AFP.
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63
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Hu RG, Tang S, Liu WY. The pH-dependent interaction of cinnamomin with lipid membranes investigated by fluorescence methods. Biol Chem 2000; 381:567-73. [PMID: 10987363 DOI: 10.1515/bc.2000.073] [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: 11/15/2022]
Abstract
Cinnamomin, a new type II ribosome-inactivating protein (RIP), was found to be able to induce the release of calcein loaded in lecithin small unilamellar vesicles and the fusion or aggregation of the lecithin liposomes. Such induction could be promoted severalfold by a pH 5.0 environment, a condition similar to that in endocytic vesicles. Lowering the pH from 7.5 to 5.0 evoked conformational changes of cinnamomin and unmasked its hydrophobic areas, including the exposure of 1-anilino-8-naphthalenesulfonate (1,8-ANS) binding sites of the molecule. Some tryptophan residues with affinity to acrylamide were demonstrated to participate in the lipid-protein interaction. The pH dependent fusogenicity of type II RIP might suggest its in vivo function as a fusogen to exert its cytotoxicity.
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Wu CW, Li AF, Chi CW, Huang CL, Shen KH, Liu WY, Lin W. Human gastric cancer kinase profile and prognostic significance of MKK4 kinase. THE AMERICAN JOURNAL OF PATHOLOGY 2000; 156:2007-15. [PMID: 10854223 PMCID: PMC1850082 DOI: 10.1016/s0002-9440(10)65073-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Alterations of protein tyrosine kinase are often associated with uncontrolled cell growth and tumor progression. Knowledge of the overall expression pattern of tyrosine kinases should prove beneficial in understanding the signaling pathways involved in gastric cancer oncogenesis and in providing possible biomarkers for gastric cancer progression. To establish a general tyrosine-kinase expression profile, degenerated polymerase chain reaction primers designed from the consensus catalytic kinase motifs were used to amplify protein tyrosine kinase molecules from gastric cancer tissues. We observed more than 50 tyrosine and serine/threonine kinases from matching pairs of gastric cancer tissue and normal mucosa. Based on this new kinase profile information, we selected the MKK4 gene for further immunohistochemical studies. Statistical analysis of MKK4 protein expression and clinicopathological features indicated that MKK4 kinase expression could serve as a significant prognostic factor for relapse-free survival and for overall survival. We demonstrated a simple and sensitive method for establishing protein tyrosine-kinase expression profiles of human gastric cancer tissues as well as for discovering novel and useful clinical biomarkers from such kinase expression profiles.
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Xu YZ, Li YJ, Hu HY, Hu R, Wu H, Liu WY. Adenine nucleotide N-glycosidase activity of the A-chain of cinnamomin characterized by 1H-nuclear magnetic resonance. Biol Chem 2000; 381:447-51. [PMID: 10937876 DOI: 10.1515/bc.2000.058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Plant ribosome-inactivating proteins specifically cleave an N-glycosidic bond of a unique adenosine in the largest ribosomal RNA, releasing an adenine from ribosomes of different sources. Here, 1H-nuclear magnetic resonance is used to analyze the enzymatic products of the A-chain of cinnamomin, a type-II ribosome-inactivating protein (RIP) acting on the nucleotides in situ. The enzymatic activities of the RIP on nine nucleotides are compared. Cinnamomin A-chain can cleave the N-glycosidic bond and release an adenine base from adenine nucleotides except 5'-ATP; however, it cannot act on 5'-GMP, 5'-CMP, and 5'-UMP. The A-chain in the mixture of cinnamomin A- and B-chain exhibits higher activity toward adenine nucleotides than the A-chain alone does, suggesting that the B-chain can conformationally stabilize the A-chain. Intact cinnamomin also exhibits lower activity toward adenine nucleotides. However, cinnamomin B-chain and heat-denatured intact cinnamomin cannot hydrolyze all the tested nucleotides. We conclude that hydrolysis of the N-C glycosidic bond of nucleotide compounds by cinnamomin A-chain has a base preference, and the negatively charged phosphate group(s) reduces the recognition ability of the A-chain to adenine nucleotide.
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Liu CM, Chen BH, Liu WY, Wu XL, Ma YX. Conversion of tributylstannylferrocene to a variety of heteroaryl ferrocenes. J Organomet Chem 2000. [DOI: 10.1016/s0022-328x(99)00733-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Liu CM, Liu WY, Liang YM, Ma YX. A Convenient Synthesis of Monosubstituted Ferrocene Heterocycles. SYNTHETIC COMMUN 2000. [DOI: 10.1080/00397910008087220] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Zhou X, Li XD, Yuan JZ, Tang ZH, Liu WY. Toxicity of cinnamomin--a new type II ribosome-inactivating protein to bollworm and mosquito. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2000; 30:259-64. [PMID: 10732994 DOI: 10.1016/s0965-1748(99)00126-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The toxicity of cinnamomin, a new type II ribosome-inactivating protein purified from the seeds of camphor tree (Cinnamomum camphora), to bollworm (Helicoverpa armigera) and mosquito (Culex pipines pallens) during larval stage was tested. The LC50 of cinnamomin to bollworm larvae fed on diet containing cinnamomin was 1839 ppm and the LC50 to larvae of mosquito was 168 ppm. The gut extract of bollworm larvae could apparently hydrolyze cinnamomin. The inhibition of protein synthesis by cinnamomin was tested in in vitro translation system of bollworm larvae, and its LC50 was determined to be approx. 14 nM. Bollworm larvae ribosome treated with cinnamomin produced a specific RNA fragment (R-fragment) characterized on urea-denatured polyacrylamide gel. Evidence was provided that hidden breaks exist in the largest ribosomal RNA of bollworm larvae.
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Xu YZ, Liu WY. Effects of the active aldehyde group generated by RNA N-glycosidase in the sarcin/ricin domain of rat 28S ribosomal RNA on peptide elongation. Biol Chem 2000; 381:113-9. [PMID: 10746742 DOI: 10.1515/bc.2000.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Effects of the active aldehyde group of ribose C1' at position 4324 of rat 28S rRNA, in the inactivated ribosome generated by RNA N-glycosidases (trichosanthin, A-chain of cinnamomin and ricin), on peptide elongation have been studied. The aldehyde group inhibits the activities of eEF1A-dependent aminoacyl-tRNA binding to the inactivated ribosome and eEF1A-dependent GTPase, but increases eEF2-dependent activity. At a high concentration of RNA N-glycosidase, the generated aldehyde group also inhibits aminoacyl-tRNA binding to the inactivated ribosome in the absence of elongation factor and translocation activity. When the aldehyde group is reduced into a hydroxyl group by sodium borohydride or blocked with an amino acid through nucleophilic addition, the activities of eEF1A-dependent aminoacyl-tRNA binding and eEF1A-dependent GTPase of the inactivated ribosome are partially restored, but the altered activities of eEF2-dependent GTPase, translocation and aminoacyl-tRNA binding in the absence of elongation factor are not normalized. Thus, reduction or blockage of the aldehyde group with sodium borohydride or amino acids might change the conformation of the S/R domain in rat 28S ribosomal RNA to meet the requirement for eEF1A-dependent reactions, but not eEF2-involved reactions.
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MESH Headings
- Aldehydes/metabolism
- Aldehydes/pharmacology
- Algal Proteins
- Animals
- Antineoplastic Agents/metabolism
- Binding Sites
- Biological Transport/drug effects
- Cytotoxins/genetics
- Endoribonucleases/chemistry
- Fungal Proteins
- GTP Phosphohydrolase-Linked Elongation Factors/pharmacology
- GTP Phosphohydrolases/drug effects
- GTP Phosphohydrolases/metabolism
- N-Glycosyl Hydrolases/metabolism
- Peptide Chain Elongation, Translational/drug effects
- Peptide Elongation Factor 1/pharmacology
- Peptide Elongation Factors/pharmacology
- Phenylalanine
- Protein Structure, Tertiary
- Protein Synthesis Inhibitors/metabolism
- Proteins/metabolism
- RNA, Ribosomal, 28S/metabolism
- RNA, Ribosomal, 28S/pharmacology
- RNA, Transfer, Amino Acyl/drug effects
- RNA, Transfer, Amino Acyl/metabolism
- Rats
- Ribosome Inactivating Proteins
- Ribosome Inactivating Proteins, Type 2
- Ricin/chemistry
- Trichosanthin/metabolism
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Tan-Wilhelm D, Witte K, Liu WY, Newman LS, Janssen A, Ellison C, Yancey A, Sanderson W, Henneberger PK. Impact of a worker notification program: assessment of attitudinal and behavioral outcomes. Am J Ind Med 2000; 37:205-13. [PMID: 10615101 DOI: 10.1002/(sici)1097-0274(200002)37:2<205::aid-ajim6>3.0.co;2-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Hundreds of worker notification programs are conducted each year to communicate occupational risks to workers. However, few attempts have been made to evaluate their effectiveness and few have described how communication theories are applied in developing notification messages. We developed and assessed the effectiveness of a worker notification program at a beryllium machining plant. METHODS We compared self-protective attitudinal and behavioral responses among workers in two plants: (1) an intervention plant that received beryllium risk notification and (2) a matched control plant that did not receive notification. RESULTS Workers receiving notification reported significantly stronger perceptions of threat and efficacy, more positive attitudes toward safety practices, and engaged in more protective behaviors than the workers at the control plant. CONCLUSIONS This study demonstrates the utility of applying communication theories in the development of notification messages and the results suggest that mass presentations may be just as effective, if not more so, than one-on-one notifications. Am. J. Ind. Med. 37:205-213, 2000. Published 2000 Wiley-Liss, Inc.
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Hao JJ, Geng C, Xie W, Gong Z, Liu WY, Wang E. Isolation and characterization of viridin, a new 65 kDa antifungal protein from the mould Trichoderma viride. Biol Chem 1999; 380:1243-5. [PMID: 10595589 DOI: 10.1515/bc.1999.158] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A new extracellular antifungal protein with a yield of 10 mg per liter was isolated from the culture medium of the mould Trichoderma viride. The protein, which we named viridin, was purified by carboxymethyl-cellulose cation-exchange chromatography and Superose 12 HR 10/30 high-performance liquid chromatography. Viridin, a basic protein of approximately 65 kDa as determined by SDS-PAGE, inhibits the growth of the cotton pathogen Verticillum dahliae, the IC50 being 6 microM.
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72
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Liu WY, Pu Z. Ribotoxins and their applications in probing the topographical structure of ribosomes. JOURNAL OF NATURAL TOXINS 1999; 8:385-94. [PMID: 10591041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Ribotoxins are a group of ribosome-inactivating proteins (RIPs) isolated mostly from plants. They inactivate ribosomes by a mechanism as RNA N-glycosidase that removes a specific adenine base from the highly conserved "S/R domain" in the largest ribosomal RNA. In this review, we introduce the major results from our laboratory in recent years on the study of the structure and function of RIPs and ribosomes: [1] Purification and characterization of the enzymatic mechanism of RIPs. Several new RIPs were purified and their RNA N-glycosidase and supercoil-dependent DNA endonuclease activities were studied. [2] The topographical structure of ribosomes. The relationship between the structure and function of ribosomes, especially of the "S/R domain" in rat 28S rRNA, were investigated by means of RIPs and other chemical probes. [3] The cytotoxicity of two RIPs to carcinoma cells. [4] Several new methods for studying RIPs and probing the structure of ribosomes were developed, i.e., radioassays for RNA N-glycosidase, glycoprotein detection by fluorescent labeling on SDS-polyacrylamide gels, and methods for small RNA sequencing.
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Zhang GP, Shi YL, Wang WP, Liu WY. Cation channel formed at lipid bilayer by Cinnamomin, a new type II ribosome-inactivating protein. Toxicon 1999; 37:1313-22. [PMID: 10400291 DOI: 10.1016/s0041-0101(99)00078-1] [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: 01/12/2023]
Abstract
Cinnamomin, a new type II ribosome-inactivating protein, purified from the seeds of Cinnamonum camphora is reconstituted into the membranes of planar lipid bilayer and giant liposome. The channel-forming activity of the cinnamomin is found and cation permeability of the channel is characterized by patch clamp. In an asymmetric solution system, bath 150/pipette 100 mM KCl, the unit conductance is 140+/-7 pS and the reversal potential is 10.4+/-0.6 mV, very close to the theoretical value of the K+ electrode. The results offer an interpretation for internalization of the RIP and the cytotoxicity difference between single and two chain RIP.
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Bai B, Wang H, Liu WY, Song CY. [Effect of anti-opioid peptide sera on the enhancement of electroacupuncture analgesia induced by neurotensin in PAG of rats]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1999; 51:224-8. [PMID: 11499020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
With the use of potassium iontophoresis induced tail-flick for measuring the pain threshold, the effects of injecting neurotensin (NT), naloxone (NX), anti-metenkephalin serum (AMEKS), anti-beta-endorphin serum (AEPS) and anti-dynorphin A1-13 serum (ADYNS) into periaqueductal gray (PAG) on electroacupuncture (EA) analgesia in rats were investigated. NT administration enhanced EA analgesia remarkably. Pre-injection of NX, AMEKS and AEPS into PAG could significantly attenuate the enhancement of EA analgesia induced by NT, but not by administration of ADYNS. The results indicate that NT in PAG is responsible for the enhancement of EA analgesia. The effect of NT may be partly mediated by met-enkephalin and beta-endorphin.
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Hu TZ, Liu WY, Jiang XP. [The result of splenopneumopexy on patients with portal hypertension in children]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 1999; 13:83-5. [PMID: 12080773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
OBJECTIVE The purpose of this study was to study the effect of splenopneumopexy for patients with portal hypertension in children. METHODS From March 1993 to April 1998, splenopneumopexy was performed on six children with portal hypertension. Doppler ultrasound and radionuclide were used to demonstrate the portopulmonary shunt after operation. RESULTS The bleeding from the esophageal varices was controlled and the esophageal varices were eliminated gradually. The symptoms pertaining to hypertension were disappeared. The patency of the shunt was maintained without the formation of thrombosis. No pulmonary complication was observed. CONCLUSION The results indicated that splenopneumopexy was a safe and effective procedure for patients with portal hypertension in children.
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