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Du YP, Zhang YP, Wang SC, Shi J, Wu SH. Function and regulation of cholecystokinin octapeptide, β-endorp hin and gastrin in anorexic infantile rats treated with ErBao Granules. World J Gastroenterol 2001; 7:275-80. [PMID: 11819774 PMCID: PMC4723536 DOI: 10.3748/wjg.v7.i2.275] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the role of cholecystokinin octapeptide (CCK-8), β-endorphin (β-EP), and gastrin in an anorexic infantile rat model and no subsequent regulation of nose peptides by the Yunpi complex prescription ErBao Granule.
METHODS: We fed infantile rats with special prepared forage. A liquid extract of ErBao Granule was administered to the rats daily for 3 weeks, CCK-8, β-EP, and gastrin concentrations in hypothalamus, gastric antrum, and plasma of the rats were measured by radioimmunoassay, and were compared with controls.
RESULTS: Treatment of rats with ErBao Granule inhibited CCK-8 secretion and increased β-EP and gastrin secretion. CCK-8 concentration in hypothalamus and plasma of model control group increased significantly and correlated negatively with food intake of models, respectively. β-EP concentration in gastric antrum and plasma of model control group decreased significantly and showed a positive correlation with food intake of models, respectively. Hypothalamus concentration of β-EP was similar in models and controls. Gastrin concentration in gastric antrum of models was lower than in the blank control group, and correlated positively to food intake of models. Finally, CCK-8 concentrations in plasma of rats showed a positive correlation with plasma β-EP (r = -0.68, P < 0.05).
CONCLUSION: The increased plasma and hypothalamus concentration of CCK-8, decreased gastric antrum and plasma level of β-EP, and decreased gastric antrum concentration of gastrin are associated significantly with the anorexia of infantile anorexic rat models produced by special forage. ErBao Granule can reverse these changes, which may be the major mechanisms of ErBao Granule simulating feeding.
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Shen XM, Wu SH, Yan CH, Zhao W, Ao LM, Zhang YW, He JM, Ying JM, Li RQ, Wu SM, Guo D. Delta-aminolevulinate dehydratase polymorphism and blood lead levels in Chinese children. ENVIRONMENTAL RESEARCH 2001; 85:185-190. [PMID: 11237505 DOI: 10.1006/enrs.2000.4230] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study investigated the relationship between the delta-aminolevulinate dehydratase (ALAD) isozymes and the blood lead levels of Chinese children. The purpose of this study was to determine the precise ALAD genotyping in Chinese children and identify the contribution of the ALAD genotype to the body lead burden. Blood samples were obtained from 109 boys and 120 girls. These children were 6-10 years old and from a single primary school. Both the school and their homes were within a community in which a large smelter was located. An environmental questionnaire was obtained for each subject, and blood lead levels and ALAD isozyme phenotype were analyzed in a double-blinded fashion. The blood lead levels of 229 children ranged from 4.5 to 26.4 microg/dl; the mean was 10.3 microg/dl and the standard deviation was 3.3 microg/dl. The gene distribution of the ALAD isozyme phenotypes in these environmentally exposed children was ALAD 1-1 (92%), ALAD 1-2, (8%), and ALAD 2-2 (0%). The mean blood level of the environmentally exposed children, who were homozygous for the ALAD1 allele, was 9.7 microg/dl; the mean for those who were heterozygous for the ALAD2 allele was 11.7 microg/dl. Using the t test, the means of the groups were different at the level of t=2.2058, P<0.05. Step-wise regression and multiple analyses of covariance were employed to control the confounders to measuring the independent contribution of the ALAD genotype on blood lead levels. After controlling the confounders, the contribution of the ALAD genotype to the blood lead level was greater and still statistically significant (F=7.3201, P<0.01). These results indicate that individuals carrying the ALAD2 allele are more likely to have sustained increases in blood lead levels when exposed to a lead-contaminated environment.
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Wu SH, Luo XD, Ma YB, Hao XJ, Zhou J, Wu DG. Two new germacranolides from Magnolia grandiflora. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2001; 3:95-102. [PMID: 11407820 DOI: 10.1080/10286020108041376] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two new sesquiterpenoids, 4,5-epoxy-13-methoxy-1(10)-germacren-12,6-olide and 4,5-epoxy-13-acetoxy-1(10)-germacren-12,6-olide, were isolated from the leaves of Magnolia grandiflora, together with six known compounds, 2alpha-hydroxy-dihydroparthenolide, parthenolide, costunolide, syringaresinol, (+) medioresinol and 6,7-dimethoxycoumarin. The structures of the new compounds were elucidated on the basis of spectroscopic methods and X-ray diffraction.
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Wu SH, Thompson CB. Evaluation of the nursing intervention classification for use by flight nurses. Air Med J 2001; 20:33-7. [PMID: 11182703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
INTRODUCTION The purpose of the study was to determine if terminology used for nursing interventions in air transport records is consistent with the Nursing Intervention Classification (NIC) system. METHODS A retrospective descriptive design was used to examine the terminology used in air transport records. The sample included the transport records for 46 cardiac patients transported by air. RESULTS Of the 7958 data elements obtained from the transport records, 1435 were nursing interventions. Ninety-nine percent of the interventions could be classified into the NIC. However, 8.5% of the NIC interventions listed did not reflect the advanced level of practice demonstrated by the flight nurses. CONCLUSION The results of the study suggest that the current version of the NIC was a useful but not a sufficient classification system for flight nurse documentation. More than 90% of the interventions could be categorized using the NIC. However, modifications are needed to reflect the advanced level of practice used by flight nurses and deal with the inconsistencies in the data classification system structure.
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Hsu CH, Chen LW, Liao YD, Wu SH, Chen C. 1H, 15N and 13C resonance assignments and secondary structure determination of the RC-RNase 2 from oocytes of bullfrog Rana catesbeiana. JOURNAL OF BIOMOLECULAR NMR 2001; 19:87-88. [PMID: 11246862 DOI: 10.1023/a:1008348302036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Wu SH, Chu JJ, Chiang CD. Increased soluble Fas ligand concentration in tuberculous pleural effusion. J Formos Med Assoc 2001; 100:32-4. [PMID: 11265257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
BACKGROUND AND PURPOSE Tuberculous (TB) pleurisy results from a delayed hypersensitivity reaction involving macrophages, T-cells, and many cytokines (including tumor necrosis factor, interferon-gamma, and interleukin 1 and 2). Infection by Mycobacterium tuberculosis induces apoptosis in gamma/delta T-cells and macrophages. Fas ligand (FasL) is a type II membrane protein that plays an important role in the regulation of apoptosis and has an intimate relation with these cells and cytokines. A soluble form of FasL (sFasL) exists in a variety of human body fluids, including serum, pleural effusion, cerebral spinal fluid, and ocular fluid. Therefore, we hypothesized that Fas activity is elevated in TB pleurisy. This study investigated the concentration of sFasL in TB pleural effusions and compared it with expression of sFasL in various other pleural effusions. METHODS Using an enzyme-linked immunosorbent assay, we investigated the sFasL concentrations of 80 pleural effusions from patients with various diagnoses. RESULTS The median sFasL concentration in the TB pleural effusion group was 104.91 pg/mL (n = 32). This was significantly higher than values in the transudate group (median value, 20.02 pg/mL, n = 9, p < 0.001) and patients with malignant effusion associated with adenocarcinoma of the lung (median value, 23.29 pg/mL, n = 14, p < 0.001). Lymphoproliferative disease could not be distinguished from TB based on sFasL concentrations in pleural effusion. CONCLUSIONS The sFasL concentration in TB pleural effusions is significantly higher than that in adenocarcinomatous pleural effusions, which are the most common malignant pleural effusions. This difference may serve as a diagnostic tool to differentiate these two most commonly encountered unexplained pleural effusions. Determination of the cellular source and the actual role of the abundant sFasL in TB pleurisy will require further investigation.
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Safo MK, Musayev FN, Wu SH, Abraham DJ, Ko TP. Structure of tetragonal crystals of human erythrocyte catalase. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2001; 57:1-7. [PMID: 11134921 DOI: 10.1107/s0907444900013767] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2000] [Accepted: 10/04/2000] [Indexed: 11/10/2022]
Abstract
The structure of catalase from human erythrocytes (HEC) was determined in tetragonal crystals of space group I4(1) by molecular-replacement methods, using the orthorhombic crystal structure as a search model. It was then refined in a unit cell of dimensions a = b = 203.6 and c = 144.6 A, yielding R and R(free) of 0.196 and 0.244, respectively, for all data at 2.4 A resolution. A major difference of the HEC structure in the tetragonal crystal compared with the orthorhombic structure was the omission of a 20-residue N-terminal segment corresponding to the first exon of the human catalase gene. The overall structures were otherwise identical in both crystal forms. The NADPH-binding sites were empty in all four subunits and bound water molecules were observed at the active sites. The structure of the C-terminal segment, which corresponds to the last exon, remained undetermined. The tetragonal crystals showed a pseudo-4(1)22 symmetry in molecular packing. Two similar types of lattice contact interfaces between the HEC tetramers were observed; they were related by the pseudo-dyad axes.
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Abstract
A new triterpenoid, 1 alpha,7 alpha-diacetoxyapotirucall-14-en e-3 alpha, 21,22,24,25-pentaol (1), and the two known compounds odoratone (2) and 2 beta,3 beta,4 beta-trihydroxypregnan-16-o ne (3) were isolated from a methanolic extract of the seed kernels of Azadirachta indica. Their structures were elucidated on the basis of spectral methods.
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Wei BL, Wu SH, Chung MI, Won SJ, Lin CN. Synthesis and cytotoxic effect of 1,3-dihydroxy-9,10-anthraquinone derivatives. Eur J Med Chem 2000; 35:1089-98. [PMID: 11248407 DOI: 10.1016/s0223-5234(00)01190-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
1,3-Dihydroxy-9,10-anthraquinone (4) was reacted with epichlorohydrin or 1,omega-dibromo-alkane to yield 1-hydroxy-3-(2,3-epoxypropoxy)-9,10-anthraquinone (5) and 1-hydroxy-3-(3-chloro-2-hydroxypropoxy)-9,10-anthraquinone (6) or 1-hydroxy-3-(omega-bromoalkoxy)-9,10-anthraquinone. Ring-opening of the epoxide (5) or 1-hydroxy-3-(omega-bromoalkoxy)-9,10-anthraquinones with appropriate amines, afforded various 1-hydroxy-3-(3-alkylamino-2-hydroxypropoxy)-9,10-anthraquinones. The synthetic compounds were tested in vitro inhibition of human T-24, Hep 3B, Hep G2, SiHa, HT-3, PLC/PRF/5 and 212 cells. Almost all compounds showed significant inhibitory activity against several different cancer cell lines. Structure-activity analysis indicated epoxidation of the hydroxyanthraquinone increased cytotoxicity against tumour cells, but ring-opening of the epoxide group with amine did not enhance the cytotoxic activity. The phosphatidylserine (PS) externalization and DNA fragmentation in SiHa cells were significantly observed after 48 h incubation with selected compound 19. The results show that 19 cause cell death by apoptosis.
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Abstract
Four compounds were isolated from dry seeds of Cipadessa baccifera (Roth) Miq. along with the known 2beta,3beta,4beta-trihydroxypregnan-16-one, febrifugin, and khaysin T. Their structures were elucidated on the basis of spectral analysis to be cipadesin, 17alpha,20R-dihydroxypregnan-3,16-dione, 1,4-epoxy-16-hydroxyheneicos-1,3,12,14,18-pentaene and 1,4-epoxy-16-hydroxyheneicos-1,3,12,14-tetraene.
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Wu SH, Lagarias JC. Defining the bilin lyase domain: lessons from the extended phytochrome superfamily. Biochemistry 2000; 39:13487-95. [PMID: 11063585 DOI: 10.1021/bi001123z] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Through pattern searches of genomic databases, new members of the growing family of phytochrome-related genes were identified and used to construct a 130-180 amino acid motif that delimits the bilin lyase domain, a subdomain of the extended phytochrome family that is sufficient for covalent attachment of linear tetrapyrroles (bilins). To test this hypothesis, portions of locus sll0821, a novel phytochrome-related gene from Synechocystis sp. PCC6803 that encodes a large protein with two potential bilin binding sites, were amplified, and the recombinant apoproteins were tested for bilin binding and phytochrome photoactivity. Our experiments indicated that both sites of this protein, termed Cph2 for cyanobacterial phytochrome 2, possessed bilin lyase activity, revealing two distinct classes of bilin lyase domains--those whose bilin adducts are red, far-red reversible and a second class whose bilin adducts are nonphotochromic. Spectroscopic analysis of photochromic phycocyanobilin and fluorescent phycoerythrobilin adducts of a 24-kDa fragment of Cph2 definitively established that the motif identified by pattern searches represents a bona fide bilin lyase domain. Site-directed mutagenesis of highly conserved charged residues within bilin lyase domains of nearly all members of the extended phytochrome superfamily has identified a glutamate residue critical for bilin binding.
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Abstract
To better understand the development of the dorsal nucleus of the lateral lemniscus (DNLL), intrinsic membrane properties and synaptic responses of DNLL neurons in brain slice preparations were examined. Intracellular recordings were taken from DNLL neurons of rat pups at postnatal days 4-8 (early group), 10-12 (intermediate group) and 16-18 (late group). In response to positive current injection, neurons in the early group displayed firing with lower frequency and a longer action potential duration in comparison to the intermediate and late groups. The action potential amplitude of DNLL neurons increased during development. Postsynaptic potentials (PSPs), with excitatory predominance, were elicited by electrical stimulation of the lateral lemniscus and commissure of Probst throughout the three age groups. Neurons showed a longer latency and rise time of the PSPs in the early group in comparison with those in the intermediate and late groups. These results suggest that the early DNLL neurons display physiological characteristics associated with immature neurons, while the other two groups tend to illustrate mature-like neuronal properties. Furthermore, it seems that the neurons at day 10-12 are in a transitional period of development, which coincides with the onset of hearing.
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Abstract
Two new compounds, cedrellin (1) and 2,6,10,15-phytatetraene-14-ol (2), together with five known compounds, 7 alpha-obacunyl acetate, 6-acetoxyobacunol acetate, 7 alpha-acetoxydihydronomilin, 2,6,10-phytatriene-1,14,15-triol and phytol were isolated from leaves of Cedrela sinensis. Their structures were elucidated on the basis of combined one- and two-dimensional spectral techniques.
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Abstract
The purpose of this study is to determine whether long-term potentiation (LTP) can be induced in the central nucleus of the inferior colliculus (ICC) by electrical stimulation of the lateral lemniscus. If LTP can be induced, is it mediated by N-methyl-D-aspartate (NMDA) and/or other receptors? Brain slices of the ICC were obtained from 14-35 day old Wistar rats. The field potentials were recorded from the ICC after GABAergic and glycinergic inhibition was suppressed. Following tetanic stimulation (50 Hz, 20 s), the amplitude of the response was increased to about 146% of control response for at least 30 min. LTP was observed in about 78% of the cases tested. Induction of LTP in the ICC required activation of both NMDA and gamma-aminobutyric acid (GABA)(B) receptors. GABAergic inhibitory postsynaptic potentials (IPSPs) were blocked by the GABA(A) receptor antagonist, but not by the GABA(B) receptor antagonist. The IPSPs were decreased by the GABA(B) receptor agonist, baclofen. The intrinsic postsynaptic membrane properties were not affected by baclofen. These results suggest that GABAergic inhibition in the ICC is mediated only by GABA(A) receptors, but that it is modulated by presynaptic GABA(B) receptors. The GABA(B) receptors in the ICC may suppress GABAergic inhibition and promote induction of LTP.
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Abstract
Four tirucallane derivatives, 3beta,22S-dihydroxy-tirucalla-7,24-dien-23-one, 22,23-epoxy-tirucalla-7-ene-3beta,24,25-triol, 3beta,25-dihydroxy-tirucalla-7,23-diene, 23,26-dihydroxy-tirucalla-7,24-dien-3-one, together with two known triterpenoids, 24,25-epoxy-3beta,23-dihydroxy-7-tirucallene, tirucalla-7,24-diene-3beta,23-diol, were isolated from Dysoxylum hainanense. Their structures were elucidated on the basis of spectroscopic evidence.
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Luo XD, Wu SH, Ma YB, Wu DG. Tetranortriterpenoids from Walsura yunnanensis. JOURNAL OF NATURAL PRODUCTS 2000; 63:947-951. [PMID: 10924171 DOI: 10.1021/np990607x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Five new tetranortriterpenoids-walsurin (1), isowalsuranolide (2), walsuranolide (3), 11beta-acetoxywalsuranolide (4), and 20, 22-dihydro-22,23-epoxywalsuranolide (5)-and three new natural tetranortriterpenoids-11beta-hydroxydihydrocedrelone (6), 11beta-acetoxydihydrocedrelone (7), and 11beta-hydroxycedrelone (8)-together with a known tetranortriterpenoid, cedrelone (9), were isolated from the bark of Walsura yunnanensis. The structures of 1-8 were determined on the basis of spectral evidence.
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Guo LW, Gao X, Zhang DW, Wu SH, Wu HM, Li YJ, Wilson SR, Richardson CF, Schuster DI. Alkaloid-fullerene systems through photocycloaddition reactions. J Org Chem 2000; 65:3804-10. [PMID: 10864768 DOI: 10.1021/jo000156h] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photocycloaddition of tertiary amines to ¿60fullerene (C(60)) is an interesting and useful reaction. We wished to extend the applications of this type of reaction through an investigation of the photoaddition of alkaloids to C(60) for the purpose of synthesizing novel and complex photoadducts that are difficult to obtain by usual methods. Irradiation of tazettine (2) or gramine (3) with C(60) in toluene leads to formation of one monoadduct (6 or 7), whereas scandine (1a) or 10-hydroxyscandine (1b) reacts with C(60) photochemically to give two products, the expected ¿6,6 monoadduct (5a, 5b) and a new type of monoadduct with a bis-¿6, 6 closed structure (4a, 4b). These new structures were characterized by UV-vis, FT-IR, (1)H NMR, (13)C NMR, (1)H-(1)H COSY, ROESY, HMQC (heteronuclear multiple-quantum coherence), and HMBC (heteronuclear multiple-bond connectivity) spectroscopy. The techniques of time-of-flight secondary ion MS (TOF-SIMS) and field desorption MS (FD-MS) were used for the mass determination. (3)He NMR analysis of the product mixture from photoaddition of 1a to C(60) containing a (3)He atom ((3)He@C(60)) led to two peaks at -9.091 and -11.090 ppm relative to gaseous (3)He, consistent with formation of a ¿6, 6-closed monoadduct and a bis-¿6,6 closed adduct. Presumably, the bis-¿6, 6 closed adducts are formed by an intramolecular ¿2 + 2 cycloaddition of the vinyl group to the adjacent 6,6-ring junction of C(60) after the initial photocycloaddition.
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Tang Y, Zou GW, Wu SH, Shi J. [Separation and determination of tyramine by reversed-phase high performance liquid chromatography]. Se Pu 2000; 18:198-201. [PMID: 12541554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
The method for separation and determination of tyramine by reversed-phase high performance liquid chromatography has been established. The effects of mobile phase on mechanism of separation based on the ion interaction are discussed. Using C8 alkyl bonded phase and 40% methanol-water solution containing Trisperchlorate as pH buffer (adjusted pH to 7.9) and ion interaction reagent and applying p-toluene sulfonamide as internal standard substance, the tyramine obtained from decarboxylation of p-tyrosine was determined. The RSD of determination was 0.66%(n = 11). The recoveries of sample were between 99.33% and 100.38%.
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Bi XL, Cao R, He JX, Han F, Wu SH. [Functional and structural study of the prokaryotic enhancer-like element VV16 from vaccinia virus genome]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2000; 16:337-40. [PMID: 11059276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
An enhancer-like element VV16 from Vaccinia virus genome DNA was obtained by using the plasmid with CAT reporter gene. Sequence analysis showed the element of 112 bp is a part of the DNA-dependent RNA polymerase, polyA polymerase and DNA polymerase (RPO30 gene). It contains 4 AT-rich regions. Detection of beta-galactosidase activity showed that VV16 in the positive direction can increase the activity 9.0 times and VV16 in the negative direction can increase 4.1 times. The RNA dot blotting confirmed the enhancing activity of the element are on the transcription level. DNA deletion experiment indicated the sequences of 10 bp at the 5' end and 12 bp at the 3' end in the element are important to its function and the sequence from nt76 to nt82 is essential to its activity.
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Chen HP, Lin CF, Lee YJ, Tsay SS, Wu SH. Purification and properties of ornithine racemase from Clostridium sticklandii. J Bacteriol 2000; 182:2052-4. [PMID: 10715017 PMCID: PMC101933 DOI: 10.1128/jb.182.7.2052-2054.2000] [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] [Received: 09/29/1999] [Accepted: 01/07/2000] [Indexed: 11/20/2022] Open
Abstract
Ornithine racemase has been purified to homogeneity from Clostridium sticklandii, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This is the first racemase known to be highly specific to ornithine. This PLP-dependent enzyme has an M(r) of 92, 000, with a K(m) for L-ornithine of 0.77 +/- 0.05 mM and a k(cat) of 980 +/- 20 s(-1).
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Wu SH, Luo XD, Ma YB, Liu JK, Wu DG, Zhao B, Lu Y, Zheng QT. Two novel secoergosterols from the fungus Tylopilus plumbeoviolaceus. JOURNAL OF NATURAL PRODUCTS 2000; 63:534-536. [PMID: 10785434 DOI: 10.1021/np990494h] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Two novel secoergosterols, 3beta-hydroxy-8alpha,9alpha-oxido-8, 9-secoergosta-7,9(11),22-triene (tylopiol A) (1) and 3beta-hydroxy-8alpha,9alpha-oxido-8,9-secoergosta-7,22 -dien-12-one (tylopiol B) (2), were isolated from the fresh fruit bodies of Tylopilus plumbeoviolaceus, along with three known compounds, ergosta-7,22-dien-3beta-ol, uridine, and allitol. Their structures were elucidated by NMR techniques, including (1)H NMR, (13)C NMR, HMQC, HMBC, and MS. The structure and stereochemistry of compound 1 were demonstrated by X-ray crystallography.
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Ko TP, Safo MK, Musayev FN, Di Salvo ML, Wang C, Wu SH, Abraham DJ. Structure of human erythrocyte catalase. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2000; 56:241-5. [PMID: 10666617 DOI: 10.1107/s0907444999015930] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Catalase (E.C. 1.11.1.6) was purified from human erythrocytes and crystallized in three different forms: orthorhombic, hexagonal and tetragonal. The structure of the orthorhombic crystal form of human erythrocyte catalase (HEC), with space group P2(1)2(1)2(1) and unit-cell parameters a = 84.9, b = 141.7, c = 232.5 A, was determined and refined with 2.75 A resolution data. Non-crystallographic symmetry restraints were employed and the resulting R value and R(free) were 0.206 and 0.272, respectively. The overall structure and arrangement of HEC molecules in the orthorhombic unit cell were very similar to those of bovine liver catalase (BLC). However, no NADPH was observed in the HEC crystal and a water was bound to the active-site residue His75. Conserved lattice interactions suggested a common growth mechanism for the orthorhombic crystals of HEC and BLC.
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Zhu M, Wu SH, Bi XL, Xue SX, Han F. [Functional and structural analysis of a prokaryotic enhancer-like element in Escherichia coli MC1061 strain]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2000; 16:27-30. [PMID: 10883271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Cat and lacZ genes were used as reporter gene and three prokaryotic enhancer-like element (MC2, MC8 and MC9) were identified in the genomic DNA of MC1061 strain. All three fragments can improve the expression of lacZ gene by 2-5 times with the orientation independence. The results of in vivo transcription and Dot blot hybridization assays suggested that MC8 regulated the expression of lacZ at transcription level. Stepwise deletion expreriments showed the functional domain of MC8 located at 450-950 bp, and in regions 450-600 bp and 840-950 bp contain at least one functional loci. Sequence data indicated three are 3 A + T rich sections in MC8, 2 of them are in the functional loci.
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Abstract
Whole-cell patch-clamp recordings were made from neurons in the rat's dorsal nucleus of the lateral lemniscus (DNLL) in a brain slice preparation. Planes of section were chosen to preserve the integrity of fibers in the commissure of Probst (CP) and postsynaptic responses were evoked by electrical stimulation along its length. Results showed that the crossed projection to the DNLL through the CP is mainly, if not exclusively, inhibitory in the rat. Inhibitory postsynaptic responses (IPSPs) evoked by stimulation of the CP were blocked by the gamma-aminobutyric acid (GABA)(A) receptor antagonist bicuculline, but were unaffected by the glycine receptor antagonist strychnine, supporting the conclusion that the crossed inhibitory projection to DNLL from the contralateral DNLL is GABAergic. Stimulation of the CP close to the DNLL frequently evoked excitatory postsynaptic responses as well as IPSPs, but stimulation near the midline evoked IPSPs only. Thus, the excitatory responses probably originated from a pathway other than the projection to the DNLL from the contralateral DNLL through the CP.
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