51
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Zhang JW, Liu JR, Zheng CX, Tao WZ, Thakor NV, Xie A. Noninvasive early detection of focal cerebral ischemia. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 2000; 19:74-81. [PMID: 11103709 DOI: 10.1109/51.887249] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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52
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Harn CH, Bae JM, Lee SS, Min SR, Liu JR. Presence of multiple cDNAs encoding an isoform of ADP-glucose pyrophosphorylase large subunit from sweet potato and characterization of expression levels. PLANT & CELL PHYSIOLOGY 2000; 41:1235-42. [PMID: 11092908 DOI: 10.1093/pcp/pcd049] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Three cDNAs (iAGPLI-1, iAGPLI-2, and iAGPLI-3) encoding an isoform of AGPase large subunit were isolated from a sweet potato cDNA library constructed from tuberous root tissue. iAGPLI-1 was 2,161 bp in length and contained an open reading frame of 517 amino acids with a calculated molecular mass of 57,689 Da. iAGPLI-2 and iAGPLI-3 were 1,804 and 1,524 bp in length, respectively, and contained partial open reading frames of 490 and 385 amino acids. Deduced amino acid sequence comparison analysis showed that iAGPLI-1 has sequence identity with iAGPLI-2 (97.9) and iAGPLI-3 (98.7%) while iAGPLI-2 and iAGPLI-3 have 96.8% sequence identity. iAGPLI-1 had the highest sequence identity of 77.8% with potato AGPase (sAGPL1). Steady-state levels of iAGPLI-1 transcripts were expressed predominantly in the stem, and moderately in the tuberous root, but not in either the roots or leaves. However, AGPase activity was present in all tissues. The expression level in the stem declined dramatically after a 12 h incubation in the dark to nearly 3% of the value under light, although the activity under a dark condition remained at half the levels in light. The activity levels were not correlated with the transcript levels. iAGPL transcripts in leaves were induced by sucrose feeding but not by glucose or fructose. Therefore, the expression of iAGPLI-1 is regulated in stem tissue preferentially and by sucrose. Southern blot analysis showed that the sweet potato genome contained several copies of iAGPLI gene probably due to polyploidy.
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MESH Headings
- Amino Acid Sequence
- Blotting, Northern
- Blotting, Southern
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Plant/genetics
- Gene Dosage
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Glucose-1-Phosphate Adenylyltransferase
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Molecular Sequence Data
- Nucleotidyltransferases/genetics
- Nucleotidyltransferases/metabolism
- Protein Subunits
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Solanaceae/enzymology
- Solanaceae/genetics
- Tissue Distribution
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53
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Wang XQ, Yu WT, Xu D, Lu MK, Yuan DR, Liu JR, Lu GT. Polymeric diaquatetra-mu;-thiocyanato-manganese(II)mercury(II) bis(N,N-dimethylacetamide) solvate. Acta Crystallogr C 2000; 56 Pt 11:1305-7. [PMID: 11077277 DOI: 10.1107/s010827010001043x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2000] [Accepted: 07/26/2000] [Indexed: 11/11/2022] Open
Abstract
In the title complex, ¿[MnHg(SCN)(4)(H(2)O)(2)].2C(4)H(9)NO¿(n), each Mn atom is octahedrally coordinated to four equatorial thiocyanate N atoms and two axial water O atoms. The Mn atom and two O atoms lie on a twofold axis. Two kinds of crystallographically independent Hg atoms (denoted Hg1 and Hg2) are tetrahedrally coordinated with four thiocyanate S atoms and each Hg atom lies on a -4 axis. N,N-Dimethylacetamide molecules are connected to coordinated water molecules through hydrogen bonds. Each pair of Mn and Hg atoms is bridged via one thiocyanate ion. An Mn(2)Hg1Hg2(SCN)(4) 16-membered ring is formed as a unit and the four metal atoms are in a chair-form tetrahedral arrangement. The units are linked with one another and form infinite two-dimensional networks.
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54
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Kim YS, Lee JH, Yoon GM, Cho HS, Park SW, Suh MC, Choi D, Ha HJ, Liu JR, Pai HS. CHRK1, a chitinase-related receptor-like kinase in tobacco. PLANT PHYSIOLOGY 2000; 123:905-15. [PMID: 10889239 PMCID: PMC59053 DOI: 10.1104/pp.123.3.905] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/1999] [Accepted: 03/17/2000] [Indexed: 05/18/2023]
Abstract
A cDNA encoding a chitinase-related receptor-like kinase, designated CHRK1, was isolated from tobacco (Nicotiana tabacum). The C-terminal kinase domain (KD) of CHRK1 contained all of the conserved amino acids of serine/threonine protein kinases. The putative extracellular domain was closely related to the class V chitinase of tobacco and to microbial chitinases. CHRK1 mRNA accumulation was strongly stimulated by infection with fungal pathogen and tobacco mosaic virus. Amino acid-sequence analysis revealed that the chitinase-like domain of CHRK1 lacked the essential glutamic acid residue required for chitinase activity. The recombinant chitinase-like domain did not show any catalytic activity for either oligomeric or polymeric chitin substrates. The recombinant KD of CHRK1 exhibited autophosphorylation, but the mutant KD with a mutation in the essential ATP-binding site did not, suggesting that CHRK1 encoded a functional kinase. CHRK1 was detected in membrane fractions of tobacco BY2 cells. Furthermore, CHRK1-GFP fusion protein was localized in plasma membranes when it was expressed in animal cells. This is the first report of a new type of receptor-like kinase containing a chitinase-like sequence in the putative extracellular domain.
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55
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Lee SS, Bae JM, Oh MS, Liu JR, Harn CH. Isolation and characterization of polymorphic cDNAs partially encoding ADP-glucose pyrophosphorylase (AGPase) large subunit from sweet potato. Mol Cells 2000; 10:108-12. [PMID: 10774756 DOI: 10.1007/s10059-000-0108-3] [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: 11/30/2022] Open
Abstract
cDNA clones encoding sweet potato AGPase large subunit (iAGPLI) from the cDNA library constructed from the tuberous root were isolated. Two clones were characterized and named iAGPLI-a and iAGPLI-b. They were 1,661 bp and 1,277 bp in length and contained partial open reading frames of 450 and 306 amino acids, respectively. Both nucleic acid and amino acid sequence identities between iAGPLI-a and iAGPLI-b were 83.8% and 97.3%, respectively. Based on the amino acid sequence analysis, iAGPLI-a and iAGPLI-b share the highest sequence identity (81%) with potato AGPase large subunit. The iAGPLI-a and iAGPLI-b genes were expressed predominantly in the stem and weakly in the tuberous root, and no transcript was expressed in other tissues. The sweet potato genome contains several copies of the iAGPLI gene.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Plant/genetics
- Gene Dosage
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Glucose-1-Phosphate Adenylyltransferase
- Isoenzymes/genetics
- Molecular Sequence Data
- Nucleotidyltransferases/genetics
- Phylogeny
- Polymorphism, Genetic
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Solanaceae/enzymology
- Solanaceae/genetics
- Tissue Distribution
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56
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Kwon SY, An CS, Liu JR, Kwak SS, Lee HS, Kim JK, Paek KH. Molecular cloning of a cDNA encoding ribosome inactivating protein from Amaranthus viridis and its expression in E. coli. Mol Cells 2000; 10:8-12. [PMID: 10774740 DOI: 10.1007/s10059-000-0008-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
In order to isolate a cDNA clone of ribosome inactivating protein (RIP), a cDNA library was constructed in Uni-ZAP XL vector with poly(A) RNA purified from leaves of Amaranthus viridis. To get the probe for screening the library, PCR of phage DNA was conducted using the vector primer and degenerate primer designed from a conserved putative active site of the RIPs. Twenty-six cDNA clones from about 600,000 plaques were isolated, and one of these clones was fully sequenced. It was 1,047 bp and contained an open reading frame encoding 270 amino acids. The deduced amino acid sequence had a putative signal sequence of 17 amino acids and a putative active site (AIQMVAEAARFFKYIE) conserved in other RIPs. E. coli cells expressing A. viridis RIP cDNA did not grow well as compared to control cells, indicating that recombinant A. viridis RIP presumably inactivated E. coli ribosomes. In addition, recombinant A. viridis RIP cDNA produced by E. coli had translation inhibition activity in vitro.
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57
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Yoon GM, Cho HS, Ha HJ, Liu JR, Lee HS. Characterization of NtCDPK1, a calcium-dependent protein kinase gene in Nicotiana tabacum, and the activity of its encoded protein. PLANT MOLECULAR BIOLOGY 1999; 39:991-1001. [PMID: 10344204 DOI: 10.1023/a:1006170512542] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We have isolated a cDNA encoding a calcium-dependent protein kinase (CDPK) in Nicotiana tabacum, which we designated NtCDPK1. The deduced amino acid sequence of NtCDPK1 suggests that this protein contains the kinase domain at the amino terminus and the autoregulatory and calmodulin-like domains at the carboxy terminus. NtCDPK1 is highly homologous to DcCPK1, a CDPK of carrot, showing 76.5% amino acid sequence identity. NtCDPK1 transcripts are present in roots, stems and flowers, but are almost undetectable in leaves. In leaves, NtCDPK1 mRNA accumulation is stimulated by phytohormones (ABA, GA and cytokinin), Ca2+, methyl jasmonate, wounding, fungal elicitors, chitosan, and NaCl. The recombinant full-length NtCDPK1 protein is catalytically active and highly stimulated by Ca2+. A truncated recombinant NtCDPK1 which lacks the C-terminal calmodulin-homologous domain also undergoes autophosphorylation, but the kinase activity is not stimulated by Ca2+. Phosphoamino acid analysis showed that NtCDPK1 phosphorylates serine and threonine residues. Finally, a 60 kDa protein which matches the expected size of NtCDPK1 was immunodetected in the membrane fraction by an antiserum reacting with NtCDPK1. Immunoprecipitation and in vitro phosphorylation using the antiserum also generated a 60 kDa phosphoprotein only in the membrane fraction. These results suggest that NtCDPK1 is associated with the membrane.
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MESH Headings
- Amino Acid Sequence
- Blotting, Southern
- Calcium/metabolism
- DNA, Complementary/chemistry
- DNA, Complementary/isolation & purification
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genes, Plant/genetics
- Molecular Sequence Data
- Phosphorylation
- Plant Growth Regulators/pharmacology
- Plant Proteins/metabolism
- Plants, Toxic
- Protein Binding
- Protein Kinases/genetics
- Protein Kinases/metabolism
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- RNA, Plant/genetics
- Sequence Homology, Amino Acid
- Nicotiana/chemistry
- Nicotiana/enzymology
- Nicotiana/genetics
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58
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Suh MC, Choi D, Liu JR. Cadmium resistance in transgenic tobacco plants expressing the Nicotiana glutinosa L. metallothionein-like gene. Mol Cells 1998; 8:678-84. [PMID: 9895119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
To understand the function of metallothioneins (MTs) in plants, we introduced the Nicotiana glutinosa MT gene into tobacco (N. tabacum) plants via an Agrobacterium mediated transformation. Full-length MT cDNA was fused between the cauliflower mosaic virus 35S (CaMV 35S) promoter and the nopaline synthase (nos) terminator of the pMBP1 binary vector in sense orientation. Tobacco leaf discs which were cocultivated with Agrobacterium carrying the chimeric MT gene, formed kanamycin-resistant shoots on medium containing kanamycin. The kanamycin-resistant shoots were subsequently rooted on medium containing 200 microM CdSO4. Approximately 30% of individual transgenic plants developed normally. Nontransgenic plants promptly underwent leaf chlorosis, and their growth and development were inhibited on MS medium containing 50 microM CdSO4. Genomic Southern blot analysis showed that the MT gene was stably integrated into the nuclear genome of transgenic tobacco plants. The expression level of MT transcripts was analyzed by RNA gel blot analysis. Self-pollinated seeds obtained from transgenic tobacco plants showing cadmium tolerance were germinated on a medium containing 100 microM CdSO4. PCR analysis from sensitive and stably resistant T2 seedlings for cadmium sulfate confirmed a high correlation between the phenotypic expression of the MT gene and the transgenic genotype, indicating that the MT gene is inherited in the next generation.
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MESH Headings
- Cadmium/pharmacology
- Cloning, Molecular
- DNA, Plant/analysis
- DNA, Plant/genetics
- Drug Resistance
- Gene Expression Regulation, Plant
- Genes, Plant/genetics
- Genome, Plant
- Metallothionein/genetics
- Plants/genetics
- Plants, Genetically Modified/drug effects
- Plants, Genetically Modified/genetics
- Plants, Toxic
- Recombinant Fusion Proteins/genetics
- Seeds/genetics
- Nicotiana/genetics
- Transformation, Genetic
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59
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Kim YS, Lee MH, Min SR, Yoo OJ, Liu JR. Frequent occurrence of transgene deletion in transgenic plants. Mol Cells 1998; 8:705-8. [PMID: 9895123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
The status of the transgene in tobacco plants transformed by Agrobacterium was analyzed with PCR. Twelve percent of the transgenic plants with the nptII gene showed different levels of transgene deletion, which was also found in transgenic watermelon (10-30%) and carrot (40-60%). It appeared that the percentage of transgenic plants carrying deleted transgenes depended on both the transgene and the plant. It is suggested that the transgene should be inserted between a right border and a selection marker to reduce the number of transgenic plants containing deleted transgenes after selection.
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60
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Liu JR, Liu PY, Tang NY, Shieh HP. Pulse-read on erasable thermal phase-change superresolution disks. APPLIED OPTICS 1998; 37:8187-8194. [PMID: 18301637 DOI: 10.1364/ao.37.008187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
New erasable thermal phase-change superresolution (EPSR) disks composed of mask and recording layers can increase recording density by the detection of the below-diffraction-limited marks within the readout spot. The formation of the aperture and the readout signal on the EPSR disk were analyzed. The feasibility of optically designed EPSR disks was evaluated by thermal simulation. A carrier-to-noise ratio of 32 dB at a mark size of 0.4 mum, 8 dB higher than that of a conventional disk, was obtained by application of a pulse-read method to the EPSR disks at a wavelength of 780 nm and a numerical aperture of 0.55.
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61
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Liu JR, Fletcher B, Page C, Hu C, Nunez G, Baker V. Bcl-xL is expressed in ovarian carcinoma and modulates chemotherapy-induced apoptosis. Gynecol Oncol 1998; 70:398-403. [PMID: 9790794 DOI: 10.1006/gyno.1998.5125] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To investigate the role of Bcl-xL in resistance to chemotherapy-induced apoptosis in ovarian carcinoma. METHODS Two human ovarian carcinoma cell lines were used in this study: A2780 and SKOV3. A2780 cells were transfected with human Bcl-xL or control plasmid alone. Expression of Bcl-xL in single cell clones was analyzed by flow cytometry and protein expression was confirmed by Western blot. For in vitro chemotherapy-induced death assays, cisplatin and Taxol were used. The percentage of apoptotic cells was determined by nuclear propidium iodide staining followed by flow cytometric analysis. Human ascites samples were used to make tumor lysates which were then analyzed for expression of Bcl-xL protein by Western blot. RESULTS A2780 cells express low levels of endogenous Bcl-xL while SKOV3 cells express high amounts as determined by Western blot. In addition, A2780 cells are sensitive to chemotherapy-induced cell death while SKOV3 cells are resistant. To determine if chemoresistance is mediated by expression of Bcl-xL, A2780 cells were transfected with Bcl-xL or control plasmid. Cells were incubated with either cisplatin or Taxol to induce apoptosis. Bcl-xL-expressing cells were highly resistant to cisplatin and Taxol compared with controls (P < 0.05). All samples of malignant ascites analyzed expressed high levels of Bcl-xL on Western blot. CONCLUSIONS The results of these studies indicate that Bcl-xL is expressed in ovarian carcinoma, and in A2780 cells functions in a manner analogous to Bcl-2 by inhibiting chemotherapy-induced apoptosis. This may have prognostic significance; previous studies have demonstrated that patients with breast cancer that overexpress Bcl-2 have low-grade, hormonally responsive tumors. In ovarian carcinoma, another Bcl-2 family member, Bcl-xL may be responsible for modulating resistance to chemotherapy-induced apoptosis.
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62
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Lee SH, Lee MH, Chung WI, Liu JR. WAPK, a Ser/Thr protein kinase gene of Nicotiana tabacum, is uniquely regulated by wounding, abscisic acid and methyl jasmonate. MOLECULAR & GENERAL GENETICS : MGG 1998; 259:516-22. [PMID: 9790583 DOI: 10.1007/s004380050843] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A cDNA encoding a protein kinase, which may be involved in the wound signal transduction pathway, was isolated from Nicotiana tabacum. The cDNA, named WAPK, is 1227 bp in length and contains an ORF of 1017 bp. The ORF encodes a polypeptide of 339 amino acids, with a calculated molecular mass of 38234 Da. Analysis of the deduced amino acid sequence shows that the N-terminal region of WAPK contains a catalytic region composed of eleven subdomains which are typically found in Ser/Thr protein kinases. This region shows 78-84% sequence identity with similar regions of abscisic acid (ABA)-induced and external-stimuli-responsive protein kinases. However, the C-terminal region of WAPK shows little homology with similar regions of Ser/Thr protein kinases, except for a 16-amino acid stretch near the end of the catalytic domain. Kinase assays using a WAPK fusion protein expressed in E. coli revealed that WAPK autophosphorylates on serine residue(s). The WAPK gene is predominantly expressed in flowers, moderately in roots, and poorly in leaves. Transcripts were not detected in stems. The WAPK gene was induced by wounding (within 1.5 h), by abscisic acid (within 0.5 h), and by methyl jasmonate (within 2 h). The induction pattern of WAPK mRNA upon wounding was not affected by treatment with diethyldithiocarbamic acid, a reagent which inhibits jasmonic acid biosynthesis. These results suggest that the WAPK gene is regulated by ABA in the wound signal transduction pathway.
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63
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Bae JM, Ahn MY, Harn CH, Jeong WJ, Jung M, Lim YP, Liu JR. Cloning and characterization of plastid ribosomal protein S16 gene from potato (Solanum tuberosum L. cv Désirée). Mol Cells 1998; 8:466-70. [PMID: 9749535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The plastid ribosomal protein s16 (rps16) gene was cloned from potato (Solanum tuberosum L. ssp. tuberosum cv Desiree) by PCR amplification to obtain a new homologous recombination site of plastid transformation. The potato rps16 genomic clone was 1627 bp in size and the coding region was interrupted by an 859 bp intron. Exon I was 40 bp, encoding 13 amino acids and exon II was 227 bp, encoding a 76 amino acid polypeptide. The nucleotide sequence of the rps16 gene from the "Désirée" potato shared perfect identity with the sequence from the "Superior" potato in the coding region. Three nucleotide substitutions, two nucleotide insertions, and one nucleotide deletion were found between the intron sequence of both "Désirée" and "Superior" cultivars. The amino acid sequence of the potato rps16 gene showed a high level of identity with rice, maize, tobacco, and mustard (84-94%) and a relatively low level compared with Bacillus stearothermophilus and E. coli (27-28%). Expression of the rps16 gene was strong in chloroplasts and transcripts were detectable in amyloplasts, suggesting that the rps16 gene is active in nonphotosynthetic plastids as well as in photosynthetic plastids. These results indicate that the potato rps16 gene can be used as a new homologous recombination site of plastid transformation for potato cultivars.
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64
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Kim YS, Lee HS, Lee MH, Yoo OJ, Liu JR. A MADS box gene homologous to AG is expressed in seedlings as well as in flowers of ginseng. PLANT & CELL PHYSIOLOGY 1998; 39:836-845. [PMID: 9787457 DOI: 10.1093/oxfordjournals.pcp.a029442] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
To study the flower development of ginseng, a MADS box cDNA (GAG2) was isolated and characterized. A comparison of the deduced amino acid sequence of GAG2 with the sequences of other MADS box proteins showed higher amino acid identities with AG (71%) from Arabidopsis thaliana, which is specifically expressed in stamens and carpels of flowers than with AGL genes (30 to 60%), suggesting that GAG2 is a ginseng homologue of AG. However northern blot analysis showed that GAG2 was expressed in seedlings. As the ginseng plant grew, the expression of GAG2 was confined to flowers. In situ hybridization experiments showed that GAG2 transcripts accumulated in the three inner whorls of flowers and in the cells surrounding the developing embryo sac. Temporal and spatial differences between GAG2 expression and AG imply that GAG2 alone is not sufficient to determine the identities of sexual organs of ginseng flowers and has additional or unique functions which differ from those of AG.
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65
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Suh MC, Cho HS, Kim YS, Liu JR, Lee HS. Multiple genes encoding serine/threonine protein phosphatases and their differential expression in Nicotiana tabacum. PLANT MOLECULAR BIOLOGY 1998; 36:315-22. [PMID: 9484443 DOI: 10.1023/a:1005943805988] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Five cDNA clones encoding the catalytic subunits of Ser/Thr protein phosphatases (PP) of Nicotiana tabacum were described. Among them, three clones (NPP1, NPP2, and NPP3) encoded type 1 PP (PP1), whereas the rest of the clones (NPP4 and NPP5) encoded type 2A PP (PP2A). These cDNA clones exhibited high sequence identity in the PP core region to the corresponding genes from animals and plants. NPP1 mRNA was predominantly expressed in flowers, whereas NPP5 mRNA was mainly detected in leaves and flowers. In contrast, the transcripts of NPP2, NPP3, and NPP4 genes were present in all tissues examined. Throughout flower development, NPP1, NPP2, NPP5 mRNAs were expressed without any significant variation at the steady-state level. Genomic Southern blot showed that tobacco genome contained multiple genes and/or pseudogenes for both type 1 and type 2A phosphatases.
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Arai N, Shiomi K, Takamatsu S, Komiyama K, Shinose M, Takahashi Y, Tanaka Y, Iwai Y, Liu JR, Omura S. Amphistin, a new melanogenesis inhibitor, produced by an actinomycete. J Antibiot (Tokyo) 1997; 50:808-14. [PMID: 9402984 DOI: 10.7164/antibiotics.50.808] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A new melanogenesis inhibitor, named amphistin, was isolated from the fermentation broth of an actinomycete strain KP-3052. Amphistin was purified from the culture filtrate by the combination of cation exchange, gel filtration, and aminosilyl silica gel chromatographic methods. The structure of amphistin was elucidated as gamma-(beta-histidinoalanino)homoalanine by NMR experiments including 1H-15N HMBC experiment and other spectroscopic analyses. Amphistin inhibited the melanogenesis of B16 melanoma cells at concentration of 6.8 microM.
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67
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Kwon SY, An CS, Liu JR, Paek KH. A ribosome-inactivating protein from Amaranthus viridis. Biosci Biotechnol Biochem 1997; 61:1613-4. [PMID: 9339569 DOI: 10.1271/bbb.61.1613] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
An antiviral protein purified from the leaves of Amaranthus viridis was named amaranthin. The in vivo antiviral activity of amaranthin was confirmed in tobacco mosaic virus (TMV) infection test on Nicotiana glutinosa leaves. The molecular mass of the amaranthin was estimated about 30 kDa by SDS-PAGE and the pI was measured as 9.8 by isoelectric focusing (IEF) analysis. Cytotoxicity of the amaranthin using in vitro translation inhibition assay was similar to that of pokeweed antiviral protein (PAP) with IC50 of 25 pM. Depurination activity (N-glycosidase activity) against animal rRNA was also confirmed.
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68
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Huh GH, Lee SJ, Bae YS, Liu JR, Kwak SS. Molecular cloning and characterization of cDNAs for anionic and neutral peroxidases from suspension-cultured-cells of sweet potato and their differential expression in response to stress. MOLECULAR & GENERAL GENETICS : MGG 1997; 255:382-91. [PMID: 9267434 DOI: 10.1007/s004380050510] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Two peroxidase (POD) cDNAs, swpal and swpn1, were isolated and characterized from suspension-cultured cells of sweet potato in order to understand the physiological function of POD isozymes. Sequence analysis showed that swpa1 encoded an anionic POD and swpn1 encoded a neutral POD. The swpa1 and swpn1 genes were both highly expressed in suspension-cultured cells in accordance with the high POD activity of these cells. Although both gene transcripts were detected in the stems of intact plants, their transcription levels were much lower than in suspension-cultured cells. During cell growth the pattern of mRNA accumulation of swpa1 differed from that of swpn1, suggesting that expression of these genes is differentially regulated by cell growth stage. In addition, the swpa1 and swpn1 genes responded differently to oxidative stress induced by chilling. The expression of swpa1 was weakly induced by 15 degrees C acclimation and strongly induced by 4 degrees C chilling, whereas the mRNA level of swpn1 was increased by 15 degrees C acclimation and reduced by 4 degrees chilling. This indicates that the two isozymes encoded by swpa1 and swpn1 might contribute to protection against cold-induced oxidative stress through different signaling pathways. In leaves, both genes were induced by wounding with broadly similar expression. patterns. Genomic analysis suggests that the two isozymes are encoded by different loci in the sweet potato genome.
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69
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Bae JM, Liu JR. Molecular cloning and characterization of two novel isoforms of the small subunit of ADPglucose pyrophosphorylase from sweet potato. MOLECULAR & GENERAL GENETICS : MGG 1997; 254:179-85. [PMID: 9108280 DOI: 10.1007/s004380050406] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Two cDNA clones encoding two different ADPglucose pyrophosphorylase (AGPase) polypeptides designated IbAGP-sTL1 (sTL1) and IbAGP-sTL2 (sTL2) were isolated from sweet potato tuberous root and leaf libraries. The two are 84.1% and 90.6% identical at the nucleotide and amino acid sequence level, respectively. They showed higher homology with previously identified small AGPase subunit polypeptides than with large subunits, indicating that they belong to the class of small AGPase subunit polypeptides. Although both isoforms were expressed in the same organs of sweet potato, including tuberous root, leaf and stem tissues, the steady-state level of sTL1 transcripts was always higher than that of sTL2. Throughout the various developmental stages of leaves examined both isoforms were actively expressed and no significant changes in mRNA level were detected. In leaves, the level of sTL1 mRNA was increased enormously by treatment with exogenous sucrose and moderately by growth under constant light, whereas the transcript level of sTL2 remained almost unaffected, indicating that sTL1 but not sTL2 is a sucrose-inducible and light-responsive gene of starch biosynthesis. sTL1 is the only sucrose-inducible gene encoding a small AGPase subunit so far characterized from higher plants. Genomic Southern analysis suggests that the two isoforms originate from different loci in the sweet potato genome.
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Tanaka Y, Yoshida H, Enomoto Y, Shiomi K, Shinose M, Takahashi Y, Liu JR, Omura S. Malolactomycins C and D, new 40-membered macrolides active against Botrytis. J Antibiot (Tokyo) 1997; 50:194-200. [PMID: 9127189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A strain of Streptomyces was found to produce two new components of the 40-membered ring macrolides, malolactomycins C and D. They inhibited the growth of Botrytis cinerea in an agar medium and a detached leaf method.
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Chen CK, Liou YM, Lee WL, Liu JR, Cheng HJ, Yang DY, Hu WH, Ting CT. The effect of thrombolytic therapy on short- and long-term cardiac autonomic activity in patients with acute myocardial infarction. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 1996; 58:392-9. [PMID: 9068205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Reduced heart rate variability after acute myocardial infarction is an important risk stratification factor for mortality and life threatening ventricular arrhythmias. In recent years, thrombolytic therapy has revolutionized the therapy of acute myocardial infarction. However, there is little information about the mechanism of the beneficial effect of thrombolysis on cardiovascular mortality. This study was launched to investigate the relationship between thrombolytic therapy and cardiac autonomic activity, and the sequential changes in heart rate variability after acute myocardial infarction. METHODS From October 1994 to July 1995, all consecutive patients with their first acute myocardial infarction were prospectively enrolled into the study. Patients without contraindication underwent thrombolytic therapy within six hours of the onset of symptoms. Other patients received conventional treatment. Ambulatory electrocardiography (EKG) was recorded on each patient 7, 90 and 180 days after acute myocardial infarction. Heart rate variability in time- and frequency-domain was analyzed. RESULTS A total of 49 patients, 45 males and 4 females, were included in this study. The short-term heart rate variability (HRV) (seven-day) in the thrombolytic group was significantly higher than in the nonthrombolytic group in SDANN and SDNN. No significant difference in rMSSD, pNN50, LF, HF or LF/HF ratio was found. The location of MI did not influence the short-term HRV following acute myocardial infarction. In patients treated with thrombolytic agent, the follow-up HRV at 90 days and 180 days increased significantly compared to the baseline HRV (seven-day) in SDANN, SDNN, LF and HF bands. For patients without thrombolytic therapy, their follow-up HRV at 90-day and 180-day increased significantly as compared to the baseline HRV (seven-day) in SDANN and SDNN only. After correction of ventricular ejection fraction, the higher short-term (seven day) HRV activities were still present in SDANN and SDNN in patients with thrombolysis as compared to those without. The 90-day and 180-day HRV did not differ between patients with and without thrombolytic agent. Three patients died suddenly during follow-up, and all showed significantly lower values of HRV than the survivors. CONCLUSIONS The findings of the present study suggest that 1) in patients with uncomplicated AMI, HRV was transiently reduced with progressive improvement within three months after AMI in both those with and without thrombolytic therapy, and 2) patients who had received thrombolytic treatment had more improved HRV early (seven days) after AMI than those who did not. This improvement, independent of the change of left ventricular function, could be associated with the beneficial effect of thrombolytic therapy in patients with AMI.
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Sharma RP, Venkatesan T, Zhang ZH, Liu JR, Chu R, Chu WK. Evidence for Large Static and Dynamic Distortions in High Tc Superconducting YBa2Cu3O 7- delta Crystals over a Wide Temperature Range. PHYSICAL REVIEW LETTERS 1996; 77:4624-4627. [PMID: 10062585 DOI: 10.1103/physrevlett.77.4624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Kim SW, Park MK, Liu JR. High frequency plant regeneration via somatic embryogenesis in cell suspension cultures of coriander (Coriandrum sativum L.). PLANT CELL REPORTS 1996; 15:751-753. [PMID: 24178164 DOI: 10.1007/bf00232221] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/1995] [Revised: 12/28/1995] [Indexed: 06/02/2023]
Abstract
Hypocotyl segments and zygotic embryos of coriander formed embryogenic calli at frequencies of up to 75% when cultured on MS medium supplemented with 1 mgl(-1) 2,4-D. Calli were transferred to MS liquid medium with 1 mgl(-1) 2,4-D to initiate cell suspension cultures. Embryogenic cells became finely dispersible in the medium as the subculture proceeded. Cultures were transferred to a nitrogen compound enriched liquid MS medium containing 2% sucrose and 0.1 mgl(-1) 2,4-D, and cultured two weeks before plating on MS basal medium. Approximately 75% of cell aggregates (1 to two mm in diameter) underwent development into globular to cotyledonary somatic embryos after two weeks of plating. Most of the embryos were subsequently regenerated into plantlets. Regenerants were successfully transplanted to potting soil and grown to maturity in a phytotron.
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Liu JR, Conaway M, Rodriguez GC, Soper JT, Clarke-Pearson DL, Berchuck A. Relationship between race and interval to treatment in endometrial cancer. Obstet Gynecol 1995; 86:486-90. [PMID: 7675366 DOI: 10.1016/0029-7844(95)00238-m] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To determine whether the poor prognosis of black women with endometrial adenocarcinoma is due to racial differences in the interval between the onset of abnormal uterine bleeding and hysterectomy. METHODS Clinical records of all 219 patients (176 white, 39 black, four other) who underwent surgical treatment of endometrial cancer during 1990-1993 at our institution were reviewed to obtain information regarding clinicopathologic features. In addition, the interval between the onset of abnormal uterine bleeding and hysterectomy was noted. RESULTS Compared with white patients, black women with endometrial cancer had a significantly higher incidence of unfavorable features, including non-endometrioid histology (38 versus 12%), stage III or IV disease (51 versus 19%), grade 3 differentiation (49 versus 18%), and poor survival (P = .003). There was no significant difference in the median interval from onset of abnormal uterine bleeding to hysterectomy between blacks (11.1 weeks) and whites (13.7 weeks), nor was the interval to treatment related to stage, grade, histologic type, myometrial invasion, or survival. In contrast, patients with a history of hormone use had a longer median interval from the onset of abnormal bleeding to treatment compared with patients who had not used hormones (19 versus 10 weeks) (P < .01), and hormone use was associated with favorable clinicopathologic features and survival. Although black women were less likely to have used hormones than white women (13 versus 44%) (P < .001), racial differences in stage, grade, and survival persisted after correcting for hormone use. CONCLUSION This study confirms that black women with endometrial cancer have a poorer outcome than white women; however, this does not appear to be due to a difference in the interval from onset of abnormal uterine bleeding to hysterectomy.
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Jeong WJ, Min SR, Liu JR. Somatic embryogenesis and plant regeneration in tissue cultures of radish (Raphanus sativus L.). PLANT CELL REPORTS 1995; 14:648-651. [PMID: 24194314 DOI: 10.1007/bf00232731] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/1994] [Revised: 01/04/1995] [Indexed: 06/02/2023]
Abstract
Hypocotyl segments of 2- to 3-week-old radish (Raphanus sativus L. cv. F1 Handsome Fall) seedlings produced yellowish compact calli when cultured on Murashige and Skoog's (MS) medium supplemented with 1 mgl(-1) 2,4-dichlorophenoxyacetic acid (2,4-D). Upon transfer onto medium containing 6-benzyladenine and α-naphthaleneacetic acid, up to 5.3% of the calli gave rise to a few somatic embryos. When subcultured for 3 to 6 months, 7% of the yellowish, compact calli produced white, compact calli which formed numerous embryos. These calli maintained their embryogenic capacity for over 18 months. When cultured on medium containing 0.1 to 3 mgl(-1) 2,4-D, up to 90% of longitudinally sliced somatic embryo halves produced calli with numerous secondary embryos. Embryos were transferred onto medium containing 0.1 mgl(-1) 2,4-D and 1 mgl(-1) abscisic acid where they developed into the cotyledonary stage. Upon transfer onto half-strength MS basal medium, approximately 90% of the embryos developed into plantlets. These plantlets were successfully transplanted in potting soil and after cold treatment they were grown to maturity in a phytotron.
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Choi MS, Kwak SS, Liu JR, Park YG, Lee MK, An NH. Taxol and related compounds in Korean native yews (Taxus cuspidata). PLANTA MEDICA 1995; 61:264-266. [PMID: 7617770 DOI: 10.1055/s-2006-958069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The concentrations of taxol and related compounds in the bark and needles of Taxus cuspidata grown on Mt. Jiri, Mt. Sobaek, and Cheju Island, and T. cuspidata var. latifolia on Ullung Island in Korea were determined by high performance liquid chromatography (HPLC). The taxane content significantly varied with the location and plant part. The taxol content in the bark of native yews from Mt. Jiri and Mt. Sobaek was high when compared to that reported for Pacific yew (T. brevifolia), whereas bark from trees on Cheju and Ullung islands contained a much lower level. Surprisingly, the needles from Cheju and Ullung islands contained a much higher level of taxol (0.022% and 0.0173%, respectively) than those of intermountain locations (0.0058% to 0.0085%), on the basis of dry weight. The bark and needles of T. cuspidata var. latifolia on Ullung Island also contained relatively high concentrations of 10-deacetylbaccatin III, 0.0497% and 0.0545%, respectively, and indicated that environmental factors may affect the quantity. Taxol in the needles was confirmed by electrospray mass spectrometry. These results suggest that foliage from yew trees growing in their natural habitats on Cheju and Ullung islands may provide a renewable source for taxol.
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Lee HS, Kim SW, Lee KW, Eriksson T, Liu JR. Agrobacterium-mediated transformation of ginseng (Panax ginseng) and mitotic stability of the inserted β-glucuronidase gene in regenerants from isolated protoplasts. PLANT CELL REPORTS 1995; 14:545-549. [PMID: 24185594 DOI: 10.1007/bf00231935] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/1994] [Revised: 12/20/1994] [Indexed: 06/02/2023]
Abstract
Cotyledonary expiants of ginseng zygotic embryos were cocultured with Agrobacterium tumefadens strain LBA4404 harboring the binary vector pBI121 for 48 h and transferred onto MS medium supplemented with 1 mgl(-1) 2,4-dichlorophenoxyacetic acid (2,4-D), 0.1 mgl(-1) kinetin, and 100 mgl(-1) kanamycin. After 8 weeks of culture, kanamycin-resistant calli formed on the cut surfaces of cotyledonary expiants and subsequently they gave rise to numerous somatic embryos. Eight weeks after transfer onto medium containing 1 mgl(-1) each of 6-benzyladenine (BA) and gibberellic acid, most of them developed into plantlets. Southern analysis confirmed that the β-glucuronidase (GUS) gene was incorporated into the genomic DNA of regenerants. Protoplasts were enzymatically isolated from transformed somatic embryo segments and cultured in liquid medium containing 60 gl(-1) myo-inositol, 1 mgl(-1) 2,4-D, 0.5 mgl(-1) BA, and 0.5 mgl(-1) kinetin. Plants were regenerated from protoplasts via somatic embryogenesis. The polymerase chain reaction method revealed that 92% of the regenerants retained the GUS gene. When treated with X-glucuronide, 78% of the regenerants showed a GUS-positive response. The overall results indicate that the transgene is stably transmitted during somatic ontogeny and stably expressed in most the regenerants, whereas it may be deleted or impaired in some portion of them.
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Hao ZY, Zhang T, Liu JR. [A seroepidemiologic survey on HCMV infection in pregnant women]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 1995; 16:85-7. [PMID: 7781053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A survey on antibodies to HCMV-IgM was carried out with the solid-phase ELISA in 6,428 pregnant women who were given perinatal medical care in six regions of Henan Province. The positive rate was 1.1%. It was found that women of different ages, stages and numbers of pregnancy had the same positive rate. And the rate in autumn was slightly higher than those in other seasons.
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Jung KH, Kwak SS, Choi CY, Liu JR. An interchangeable system of hairy root and cell suspension cultures ofCatharanthus roseus for indole alkaloid production. PLANT CELL REPORTS 1995; 15:51-54. [PMID: 24185653 DOI: 10.1007/bf01690252] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/1995] [Revised: 05/15/1995] [Indexed: 06/02/2023]
Abstract
Hairy roots ofCatharanthus roseus obtained by co-cultivation of hypocotyl segments withAgrobacterium rhizogenes, and cultured in SH (Schenk and Hildebrandt) basal medium, formed two types of calli when subcultured in SH medium with 1 mg/1 α-naphthaleneacetic acid and 0.1 mg/l kinetin. One of them, a compact callus, when re-subcultured in SH basal medium gave rise to hairy roots again. A rhizogenic cell suspension culture was established from this type of callus. When cultured in SH medium with growth regulators, the rhizogenic callus produced catharanthine at a level of 41% of the level in the initial hairy roots. Upon transfer to SH basal medium, regenerated hairy roots produced this alkaloid at the original level of 1.5 mg/g dry wt. Using this cell/hairy root interchange system a new management system for hairy root culture in bioreactors has been devised and examined involving production of biomass in the form of a cell suspension in medium supplemented with growth regulators, and catharanthine production by hairy roots regenerated from these cells in medium without growth regulators.
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Kim SW, Jung KH, Kwak SS, Liu JR. Relationship between cell morphology and indole alkaloid production in suspension cultures of Catharanthus roseus. PLANT CELL REPORTS 1994; 14:23-26. [PMID: 24194221 DOI: 10.1007/bf00233292] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/1994] [Revised: 06/07/1994] [Indexed: 06/02/2023]
Abstract
The relationship between the morphology and indole alkaloid production of Catharanthus roseus cells was investigated. Eleven cell lines were randomly selected from protoplast-derived clones. In each line, most of the cells maintained only one of the two shapes, either spherical or cylindrical. The cell aspect ratio (cell length/width) for most isolates was stable for more than two years of subculture. Cell division patterns of spherical and cylindrical cell isolates were different and patterns of division remained stable in each phenotype and were not considerably affected by auxin or cytokinin levels in the culture media. These observations indicate that cell morphology of our isolates is stable and probably internally determined. Production of the indole alkaloids, ajmalicine and catharanthine was significantly greater when the cell aspect ratio was more than 2.8.
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Chiung YM, Hayashi H, Matsumoto H, Otani T, Yoshida K, Huang MY, Chen RX, Liu JR, Nakayama M. New metabolites, tetrahydrofuran lignans, produced by Streptomyces sp. IT-44. J Antibiot (Tokyo) 1994; 47:487-91. [PMID: 8195049 DOI: 10.7164/antibiotics.47.487] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Kim SW, Song NH, Jung KH, Kwak SS, Liu JR. High frequency plant regeneration from anther-derived cell suspension cultures via somatic embryogenesis in Catharanthus roseus. PLANT CELL REPORTS 1994; 13:319-322. [PMID: 24193829 DOI: 10.1007/bf00232629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/1993] [Revised: 12/31/1993] [Indexed: 06/02/2023]
Abstract
A system for high frequency plant regeneration from cell suspension cultures in Catharanthus roseus is described. Calli were obtained from anthers cultured on Murashige and Skoog's medium supplemented with 1 mgl(-1) α-naphthaleneacetic acid and 0.1 mgl(-1) kinetin. After the second subculture on solid medium, embryogenic callus was identified and transferred to liquid medium to initiate suspension cultures. Cells dispersed finely in the medium were subcultured at 14-day intervals. Upon plating onto the basal medium, yellowish compact colonies proliferated from the cells and more than 80% of them gave rise to somatic embryos. Subsequently, plantlets developed from the embryos. Both the plantlets and the source plants showed the normal somatic chromosome number of 2n=2x=16.
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Kang B, Zhu TB, Du JY, Liu JR, Huang JH. Sonographic diagnosis of acute hematogenous osteomyelitis in the early stage. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 1994; 14:61-4. [PMID: 7877198 DOI: 10.1007/bf02888062] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This article presents sonographic diagnosis of acute hematogenous osteomyelitis in early stage. 24 children with clinically suspected acute hematogenous osteomyelitis were detected to have subperiosteal abscesses by ultrasound during four to fourteen days after onset. The mean length and anteroposterior distance of the subperiosteal abscesses were 86.4 mm and 10.7 mm, respectively. Of 24 cases of subperiosteal abscesses, aspiration performed under ultrasound guidance revealed purulent fluid in all and 23 were verified surgically. The results obtained indicate that ultrasound can be used in diagnosis of acute hematogenous osteomyelitis in the early stage. The earliest case was diagnosed by ultrasound 4 days after onset. By use of ultrasound, differentiation diagnosis of acute hematogenous osteomyelitis from other diseases such as cellulitis, soft tissue abscess, acute septic arthritis and malignant bone tumors is also discussed.
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Choi PS, Soh WY, Kim YS, Yoo OJ, Liu JR. Genetic transformation and plant regeneration of watermelon using Agrobacterium tumefaciens. PLANT CELL REPORTS 1994; 13:344-8. [PMID: 24193834 DOI: 10.1007/bf00232634] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/1993] [Revised: 12/16/1993] [Indexed: 05/09/2023]
Abstract
Adventitious shoots formed on the proximal cut edges of different cotyledonary explants of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai; cvs. Sweet Gem and Gold Medal] cultured on Murashige and Skoog's (MS) medium with 1 mgl(-1) 6-benzyladenine (BA). Light (16-h photoperiod, about 7 Wm(-2) cool-white fluorescent lamps) was essential for shoot formation. To obtain transformed plants, cotyledonary explants of 'Sweet Gem' were cocultured with Agrobacterium tumefaciens LBA4404, a disarmed strain harboring a binary vector pBI121 carrying the CaMV 35S promoter-β-glucuronidase (GUS) gene fusion used as a reporter gene and NOS promoter-neomycin phosphotransferase gene as a positive selection marker, for 48 h on MS medium with 1 mgl(-1) BA and 200 μM β-hydroxyacetosyringone. After 48 h of culture, explants were transferred to medium with 1 mgl(-1) BA 250 mgl(-1) carbenicillin, and 100 mgl(-1) kanamycin and cultured in the light. Adventitious shoots formed on the explants after 4 weeks of culture. When subjected to GUS histochemical assay, young leaves obtained from the shoots showed a positive response at a frequency of up to 16%. Preculturing cotyledonary explants on MS medium with 1 mgl(-1) BA for 5 d enhanced the competence of the cells to be transformed by Agrobacterium. Southern blot analysis confirmed that the GUS gene was incorporated into the genomic DNA of the GUS-positive regenerants. The transformed plants were grown to maturity.
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Huebener DV, Liu JR. Maxillary orthopedics. Clin Plast Surg 1993; 20:723-32. [PMID: 8275636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Although there may never be uniformity of opinion on the use of maxillary orthopedic appliances or definitive data supporting their universal use in treatment regimens, they are an integral part of cleft lip and palate care. Many appliances, both active and passive, are used by teams of highly skilled specialists to normalize the congenital alveolar defect. The major difficulty in reaching a consensus among care providers is due to maxillary orthopedics being but one interventional aspect of a sequence of events in the habilitation effort. Cleft care begins in infancy and extends throughout the developmental years. The period of assessment of treatment regimens and outcomes extends almost over a researcher's lifetime. By placing the cleft structures in a more favorable oral configuration in concert with the oral environment, the greatest growth potential can be achieved.
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Kang B, Zhu TB, Liu JR, Chen RQ, Huang JH. Sonographic diagnosis of intramuscular hemangiomas. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 1993; 13:161-2. [PMID: 8295264 DOI: 10.1007/bf02886508] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This article reports 10 cases of intramuscular hemangiomas diagnosed by ultrasound. The results obtained demonstrated that the intramuscular hemangiomas were revealed sonographically as a spindle-shaped or ellipse-shaped mass with a mixed echo structure in the skeletal muscle, and usually with small calcifications. The solid parts of the tumor most commonly have a medium echogenicity, but few hyperechogenicity. The cavity or sinus containing blood has a hypoecho or echo-free structure.
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Kang B, Zhu TB, Du JY, Liu JR, Chen RQ, Huang JH. Ultrasound diagnosis of effusion of the hip. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 1993; 13:156-60. [PMID: 8295263 DOI: 10.1007/bf02886507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This paper reports on two prospective studies of ultrasound examination of the hip in 150 healthy subjects and 50 patients with hip joint diseases. The sagittal distance of the anterior recess of the hip was measured on the sonogram of the sagittal section. The normal value in adults, teenagers and children was 4.54 mm +/- 0.99 mm, 4.27 mm +/- 1.26 mm and 3.40 mm +/- 0.93 mm, respectively. Ultrasound examination of both hips in 50 patients with hip joint diseases showed that the sagittal distance of the anterior recess was significantly widened in the symptomatic side, and the mean value in the symptomatic side and normal side was 12.02 mm +/- 3.68 mm, and 4.12 mm +/- 1.15 mm, respectively. Ultrasound showed echo-free area in anterior recess in 42 hips, hypoecho and medium echo area in 8 hips. Of 50 patients undergoing plain radiography, 33 showed bony changes of the hip, and the remaining 17 no change whatever. The results obtained demonstrated that ultrasound can accurately detect effusion of the hip, what is more, it is easy to operate, inexpensive, noninvasive, convenient for follow-up and without radiation damage.
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Song KM, Park SW, Hong WH, Lee H, Kwak SS, Liu JR. Isolation of vindoline from Catharanthus roseus by supercritical fluid extraction. Biotechnol Prog 1992; 8:583-6. [PMID: 1369042 DOI: 10.1021/bp00018a018] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Vindoline was extracted from the leaves of Catharanthus roseus over the ranges of 35-70 degrees C and 100-300 bar using supercritical carbon dioxide with and without the addition of 3 wt % ethanol as a cosolvent. The vindoline contents in the extracts were determined by HPLC and identified by LC/MS. The remarkable highest vindoline concentration, 58 wt %, was obtained at the lowest temperature, 35 degrees C, and the highest pressure, 300 bar, of this study. The use of a cosolvent only slightly improved the extraction yields or selectivities at some experimental conditions.
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Clark DE, D'Antonio LL, Liu JR, Welch TB. Radiographic demonstration of oronasal fistulas in patients with cleft palate with the use of barium sulfate contrast. ORAL SURGERY, ORAL MEDICINE, AND ORAL PATHOLOGY 1992; 74:661-70. [PMID: 1437070 DOI: 10.1016/0030-4220(92)90362-t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The purpose of this investigation was to determine the overlapping and unique contributions that radiographic techniques might provide for accurate characterization of hard palate fistulas associated with cleft palate. Five subjects with oronasal fistulas were selected for radiographic imaging, and their informed consent was obtained. Results indicated that radiographs with contrast can provide important supplemental and unique information. Qualitative descriptions of the inferior-superior course and location, and the size of the narrowest aperture could be obtained from the combination of maxillary occlusal, posteroanterior tomographic, and lateral tomographic projections. This information could not be obtained from the common clinical methods in use to describe fistulas. This technique can provide valuable information to all members of a multidisciplinary cleft palate team to document palatal fistulas for both clinical and research purposes.
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Min SR, Yang SG, Liu JR, Choi PS, Soh WY. High frequency somatic embryogenesis and plant regeneration in tissue cultures of Codonopsis lanceolata. PLANT CELL REPORTS 1992; 10:621-623. [PMID: 24212875 DOI: 10.1007/bf00232383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/1991] [Revised: 10/23/1991] [Indexed: 06/02/2023]
Abstract
Culture conditions for high frequency somatic embryogenesis and plant regeneration from cotyledonary explants of Codonopsis lanceolata are described. The maximum induction frequency of somatic embryos from cotyledonary explants was 80% on Murashige and Skoog (MS) medium containing 6% sucrose with 1 mg/l 2,4-dichlorophenoxyacetic acid and 10% coconut water. Upon transfer onto MS basal medium containing 3% sucrose, most somatic embryos developed into plantlets.
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Arya S, Liu JR, Eriksson T. Plant regeneration from protoplasts of Panax ginseng (C.A. Meyer) through somatic embryogenesis. PLANT CELL REPORTS 1991; 10:277-281. [PMID: 24221656 DOI: 10.1007/bf00193141] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/1991] [Revised: 05/02/1991] [Indexed: 06/02/2023]
Abstract
Protoplasts of Panax ginseng were isolated from embryos obtained from the 4-year old embryogenic cell line KCTC PCL 49031 which was derived from a zygotic embryo. High protoplast yields of 22-25 × 10(6) protoplast / g tissue were obtained following 5-6 h digestion with 2% Cellulysin, 1% Pectinase and 1% Macerasae in half strength Murashige and Skoog's medium containing 12% mannitol. A plating density of 1×10(5) protoplasts /ml was found optimal for protoplast culture. An initial division frequency of 10% was obtained in an agarosegelled defined medium. Myo-inositol (6%) was found to be the most suitable osmoticum. Somatic embryos were formed from protoplast derived embryogenic callus, which regenerated into plantlets.
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93
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Shi YH, Zhao BR, Zhao YY, Li L, Liu JR. Superconducting and normal-state properties of MoNx thin films. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 38:4488-4491. [PMID: 9946835 DOI: 10.1103/physrevb.38.4488] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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94
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Wang L, Liu JR, Yin GK. [Study on the relationship between the concentration and transparency of 25% ascorbic acid injection]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1987; 18:389-91. [PMID: 3449433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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95
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Liu JR, Cantliffe DJ. Somatic embryogenesis and plant regeneration in tissue cultures of sweet potato (Ipomea batatas Poir.). PLANT CELL REPORTS 1984; 3:112-115. [PMID: 24253438 DOI: 10.1007/bf02441013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/1984] [Revised: 05/07/1984] [Indexed: 06/02/2023]
Abstract
Leaf, shoot-tip, stem, and root explants of sweet potato (Ipomea batatas Poir.) gave rise to two kinds of callus on nutrient agar medium containing 0.5 to 2.0 mg/l 2,4-D. One callus, bright- to pale-yellow, was compact and organized, while the other was dull-yellow and friable. The former callus gave rise to numerous globular and heart-shaped embryoids. When transferred onto hormone-free medium, the embryoids readily developed into a torpedo-shape before germination. The plantlets were transplanted to soil where they flowered and formed storage roots at maturity.
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96
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McLennan H, Hicks TP, Liu JR. On the configuration of the receptors for excitatory amino acids. Neuropharmacology 1982; 21:549-54. [PMID: 6287337 DOI: 10.1016/0028-3908(82)90046-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Separate receptors are recognized for the excitation of mammalian neurones by (a) L-glutamic and quisqualic acids and (b) N-methyl-D-aspartic (NMDA), and other amino acids which have conformationally restricted molecules. Several other compounds, both agonists and antagonists, have been examined, and it is concluded that (i) the NMDA receptor reacts preferentially with substances in a relatively extended configuration, (ii) the glutamate/quisqualate receptor prefers folded molecules and (iii) the distance separating the amino group from the distal anionic function is the critical one determining receptor preference.
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