2351
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Liu W. [Changes in transmembrane action potentials and monophasic action potentials of phase 3 intraventricular block in rabbits]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1991; 19:259-62, 269. [PMID: 1667520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The model of phase 3 intraventricular block was produced in 10 rabbits by giving 2.5% solution of potassium chloride intravenously under natural breathing and sinus rhythm. Transmembrane action potentials and monophasic action potentials were recorded respectively. The results showed that RP, APA, Vmax, MAPA and MVmax all decreased and both APD and MAPD shortened at the time of ventricular conduction block, when ventricular conduction was improved by vagal stimulation, RP, APA, Vmax, MAPA and MVmax all increased and both APD and MAPD lengthened. In addition, APD and MAPD measured at the same site in normal conduction, conduction block and conduction improved by vagal stimulation were in consensus.
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2352
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Liu W, Hu Z. [Status quo and prospects of oral liquid prepared from Chinese drugs]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:501-4, 513. [PMID: 1804191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper reviews the rise of oral liquids and their preparations, control standards, pharmacological research and clinical pharmacy, etc. On the basis of investigation, an overall discussion is given in respect to product variety and sale, pharmaceutical research and development, and social benefit from new products, so as to highlight the merits of Chinese medicinal materials.
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2353
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Liu W. [Reconstitution of osteoinductive bone xenograft: bioassay in mice]. ZHONGHUA YI XUE ZA ZHI 1991; 71:378-80, 28. [PMID: 1659479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
How to eliminate the antigenicity of bone xenograft while retaining its osteoinductive activities is an unsolved problem in the orthopaedic field. This paper reports an encouraging approach to the question by the following procedures extracting the bone morphogenetic protein (BMP) from cortical bone; eliminating the antigenicity of cancellous bone by chemical extraction; and reconstituting the graft with the treated cancellous bone serving as a delivery medium for BMP. This composite graft is accepted immunologically, and is also osteoinductive in the heterogenous host. In point of delivery medium of BMP, the cancellous bone xenograft is the best choice due to its abundant sources. Bioassay in mouse showed that the reconstituted graft, including only 0.5 mg BMP, demonstrated a definitive osteoinductive ability. In addition, this paper first furnished the information that the BMP aggregate from chemical extraction as described in the literature is also antigenic in the heterogenous host.
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2354
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Lu YA, Clavijo P, Galantino M, Shen ZY, Liu W, Tam JP. Chemically unambiguous peptide immunogen: preparation, orientation and antigenicity of purified peptide conjugated to the multiple antigen peptide system. Mol Immunol 1991; 28:623-30. [PMID: 1861679 DOI: 10.1016/0161-5890(91)90131-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We described a novel and simple approach to prepare chemically unambiguous peptide immunogen using the multiple antigen peptide (MAP) approach. This approach requires the conjugation of two purified components: a chloroacetylated oligomeric lysine core matrix and a synthetic peptide containing cysteine at either the carboxyl or amino terminus. The resulting MAP is structurally unambiguous and contains a quantifiable amount of peptide antigens. Furthermore, this method also provides a flexible strategy to link a peptide antigen to the core matrix at the desirable orientation to mimic the native molecule. The carboxyl fragment 43-50 of human transforming growth factor alpha (TGF alpha) was used as a test model for this approach. Antipeptide antibodies did not recognize the "reverse immunogen" in which the peptide was attached to the MAP core matrix at a reverse orientation. To determine the specificity of the antibodies, we used two series of point-substituted TGF alpha analogs containing either alanine or the corresponding D-amino acid replacement to map the antigenic site. The alanine analogs were used to determine the contribution of the side chain while the D-amino acid analogs were used to determine the importance of backbone conformation. The antigen site was found to consist of four residues (Asp47-Leu48-Leu49-Ala50) at the distal end of the peptide-MAP conjugate. The results provide a clear explanation for the specificity of the antipeptide antibodies and their failure to recognize the "reverse immunogen" since the distal and the flexible end of the peptide-MAP construct constitutes the antigenic site. Furthermore, our results also suggests a strategy of placing the antigenic portion of a short-peptide at the distal end in the MAP approach to prepare immunogen.
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2355
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Xiao B, Wu H, Liu W, Xu S. [Autologous mixed lymphoma reaction in patients with malignant lymphoma]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1991; 22:131-3. [PMID: 1838533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Human T cells can be induced to proliferate in vitro when they are cocultured with autologous Non-T cells. This phenomenon has been termed the autologous mixed lymphocyte reaction, AMLR. In this study, AMLR was assessed in 14 untreated patients with lymphoma and 13 age-and-sex-matched healthy controls. This difference was significant (P less than 0.001), suggesting that patients with lymphoma may have impaired AMLR.
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2356
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Jiang D, Liu W. Thick needle treatment for periomitis. J TRADIT CHIN MED 1991; 11:112-4. [PMID: 1861517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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2357
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Bitar KM, DeGrand T, Edwards R, Gottlieb S, Heller UM, Kennedy AD, Kogut JB, Krasnitz A, Liu W, Ogilvie MC, Renken RL, Rossi P, Sinclair DK, Sugar RL, Teper M, Toussaint D, Wang KC. Hadron thermodynamics with Wilson quarks. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1991; 43:2396-2400. [PMID: 10013622 DOI: 10.1103/physrevd.43.2396] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2358
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Liu W, Madsen NB, Braun C, Withers SG. Reassessment of the catalytic mechanism of glycogen debranching enzyme. Biochemistry 1991; 30:1419-24. [PMID: 1991122 DOI: 10.1021/bi00219a036] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The amylo-1,6-glucosidase catalytic activity of glycogen debranching enzyme allows it to hydrolyze alpha-D-glucosyl fluoride, in the absence or presence of glycogen or oligosaccharides, releasing equal amounts of fluoride and glucose at rates comparable to those seen with the natural substrates. 2-Deoxy-2-fluoro-alpha-D-glucosyl fluoride is found to be a poor substrate, rather than the covalent inhibitor that would be expected for a glucosidase which catalyzes hydrolysis of the glycosidic linkage with retention of anomeric configuration. In fact, analysis of the glucosidase reaction by NMR reveals that the debranching enzyme hydrolyzes the glycosidic linkage with inversion of configuration, releasing beta-D-glucose from both alpha-glucosyl fluoride and its natural substrate, the phosphorylase limit dextrin. In contrast, its transferase activity necessarily proceeds with retention of configuration. As has been seen with other "inverting" glycosidases, the debranching enzyme releases beta-D-glucose from beta-D-glucosyl fluoride in the presence of oligosaccharides such as maltohexaose and cyclomaltoheptaose but, unlike the others, not in their absence. An intermediate glucosyl-alpha-(1,6)-cyclomaltoheptaose has been detected by NMR analysis. In the presence of a water-soluble carbodiimide, a single mole of glycine ethyl ester is incorporated into each mole of the debranching enzyme, resulting in its inactivation when measured by the combined assay for both transferase and glucosidase activities. Measurement of the latter two activities independently indicates that it is the transferase activity which is inactivated, while the glucosidase activity, measured with alpha-D-glucosyl fluoride as substrate, is unaffected.(ABSTRACT TRUNCATED AT 250 WORDS)
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2359
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Chen D, Wang J, Liu W. [Analytical studies on amino acids and trace elements in donkey-hide gelatin]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:83-4, 126. [PMID: 1872968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
This paper reports the contents of amino acids in donkey-hide gelatin made in different pharmaceutical factories before and after processing. An analytical comparison of trace elements in the gelatin is also presented.
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2360
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Liu W. [Quantitative analysis of bergenin in herba Ardisia japonica Bl by TLC-densitometric method]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:102-4, 128. [PMID: 1872959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A method for the determination of bergenin content in Herba Ardisia japonica was established by the use of TLC-densitometry. The method is sensitive, simple and convenient, with a recovery of 101.2%.
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2361
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Waterhouse BD, Sessler FM, Liu W, Lin CS. Second messenger-mediated actions of norepinephrine on target neurons in central circuits: a new perspective on intracellular mechanisms and functional consequences. PROGRESS IN BRAIN RESEARCH 1991; 88:351-62. [PMID: 1667548 DOI: 10.1016/s0079-6123(08)63822-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Ever since the initial demonstration of a widespread distribution of noradrenergic fibers to functionally diverse regions of the mammalian forebrain, there has been considerable interest in determining the electrophysiological effects of norepinephrine (NE) on individual neurons within these target areas. While early studies showed that NE could directly inhibit cell firing via increased intracellular levels of cyclic AMP, more recent work has revealed a spectrum of noradrenergic actions, which are more accurately characterized as neuromodulatory. More specifically, numerous experimental conditions have been described where NE at levels subthreshold for producing direct depressant effects on spontaneous firing can facilitate neuronal responses to both excitatory and inhibitory synaptic stimuli. The goal of this report is to review recent evidence which suggests that the various modulatory actions of NE on central neurons result from the activation of different adrenoceptor-linked second messenger systems. In particular, we have focused on the candidate signal transduction mechanisms that may underlie NE's ability to augment cerebellar and cortical neuronal responsiveness to GABAergic synaptic inputs. The consequences of such NE-induced changes in synaptic efficacy are considered not only with respect to their influences on feature extraction properties of individual sensory cortical neurons but also with regard to the potential impact such actions would have on the signal processing capabilities of a network of noradrenergically innervated cortical cells.
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2362
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Adams L, Abercrombie E, Akaoka H, Alexinsky T, Andre P, Astier B, Aston-Jones G, Barnes C, Berridge C, Bobker D, Bongers C, Caffé A, Cardo B, Carlton S, Chan J, Chan-Palay V, Charléty P, Cheun J, Chiang C, Chouvet G, Christie M, Cirelli C, Clark F, Collewijn H, Curtis A, d'Ascanio P, Drolet G, Ennis M, Finlayson P, Foote S, Fornal C, Fritschy J, Fung S, Grove K, Grzanna R, Guyenet P, Harley C, Harris G, Holstege J, Horn E, Jacobowitz D, Jacobs B, Jones B, Jones C, Jones S, Kasamatsu T, Kempf E, Levine E, Lin CS, Liu W, Manzoni D, Markram H, Marshall K, McCormick D, Moises H, Morilak D, Mormède P, Nakamura S, Nassif-Caudarella S, Olpe HR, Osmanović S, Palacios J, Pape HC, Pieribone V, Pineda J, Pompeiano M, Pompeiano O, Proudfit H, Rasmussen K, Reddy V, Richter-Levin G, Rowe B, Sakai K, Sara S, Segal M, Sessler F, Shefner S, Shiekhattar R, Shipley M, Sklair L, Sorkin L, Speth R, Stafford I, Steinmann M, Sutin E, Tononi G, Valentino R, van Bockstaele E, van Leeuwen F, van Neerven J, Velley L, Velly J, Waterhouse B, Westlund K, Willis W, White S, Williams J, Williamson A, Woodward D, Yeh H, Zhuo H, Zhang D. List of Contributors. PROGRESS IN BRAIN RESEARCH 1991. [DOI: 10.1016/s0079-6123(08)63794-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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2363
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Liu W, Nikaido H. Contribution of the cell-surface-associated enzyme in the Zimmermann-Rosselet assay of outer membrane permeability of beta-lactam antibiotics. Antimicrob Agents Chemother 1991; 35:177-9. [PMID: 2014974 PMCID: PMC244962 DOI: 10.1128/aac.35.1.177] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Analysis of beta-lactam hydrolysis by intact cells of several strains of enteric bacteria suggests that a significant fraction of beta-lactamase molecules is present at a location directly accessible for the substrates in the medium. We propose a method to correct for the error introduced by these "surface-exposed" enzymes in the Zimmermann-Rosselet assay of outer membrane permeability.
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2364
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Lefebvre PP, Van de Water TR, Represa J, Liu W, Bernd P, Modlin S, Moonen G, Mayer MB. Temporal pattern of nerve growth factor (NGF) binding in vivo and the in vitro effects of NGF on cultures of developing auditory and vestibular neurons. Acta Otolaryngol 1991; 111:304-11. [PMID: 1648856 DOI: 10.3109/00016489109137392] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
NGF binding patterns reflect the presence of receptors for this growth factor. High specific binding of 125I 2.5 S-NGF was observed for the 11 gestation day (gd) statoacoustic ganglion (SAG) with lower levels recorded for both 14 gd acoustic ganglion (AG) and vestibular ganglion (VG) samples. Fourteen day AG cells were more than twice as active for binding NGF when compared to VG samples of the same gestational age. Both whole ganglion explants and dissociated cell cultures were grown in chemically defined medium for short term culture to assay changes in neurite outgrowth and survival of neurons in response to the addition of exogenous 2.5 S-NGF. The most vigorous neurite outgrowth and neuronal survival responses were produced by 11 gd SAG samples treated with NGF. Acoustic ganglion specimens of both 11 gd and 14 gd embryos were much more responsive to the neurotrophic effects of NGF when compared to the responses of their VG counterparts. There was a correlation between NGF binding ability and in vitro responsiveness to exogenous NGF. We hypothesize based on the results of this study that NGF (and/or a member of the NGF family of growth factors) is involved in the control of developmentally regulated neuronal cell death of SAG neurons and may play a role in the innervation of developing inner ear sensory structures.
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2365
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Bitar KM, Edwards R, Heller UM, Kennedy AD, Liu W, DeGrand TA, Gottlieb S, Krasnitz A, Kogut JB, Renken RL, Ogilvie MC, Rossi P, Sinclair DK, Wang KC, Sugar RL, Teper M, Toussaint D. Hadron spectrum in QCD at 6/g2=5.6. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1990; 42:3794-3818. [PMID: 10012790 DOI: 10.1103/physrevd.42.3794] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2366
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Liu W, Parrott WA, Hildebrand DF, Collins GB, Williams EG. Agrobacterium induced gall formation in bell pepper (Capsicum annuum L.) and formation of shoot-like structures expressing introduced genes. PLANT CELL REPORTS 1990; 9:360-364. [PMID: 24227055 DOI: 10.1007/bf00232399] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/1990] [Revised: 09/18/1990] [Indexed: 06/02/2023]
Abstract
The objective of this research was to define an in vitro regeneration and transformation system for bell pepper (Capsicum annuum L.) using six cultivars and one Guatemalan wild accession. The wild accession exhibited the best regeneration response. Only occasional elongation of shoot buds in 'Yolo Wonder L' was achieved by culture in the dark on a medium containing 10 mg/l BA and l mg/l IAA. Transformed shoot buds and leaf-like structures were obtained, showing beta- glucuronidase activity predominantly in the vascular and perivascular tissues, with no indication of contaminating Agrobacterium in the tissues. Attempts to regenerate whole transgenic plants from transformed shoot buds were unsuccessful.
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2367
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Bitar KM, DeGrand T, Edwards R, Gottlieb S, Heller UM, Kennedy AD, Kogut JB, Krasnitz A, Liu W, Ogilvie MC, Renken RL, Rossi P, Sinclair DK, Sugar RL, Teper M, Toussaint D, Wang KC. Quantum chromodynamics at 6/g2=5.60. PHYSICAL REVIEW LETTERS 1990; 65:2106-2109. [PMID: 10042455 DOI: 10.1103/physrevlett.65.2106] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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2368
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Chen D, Liu Z, Tang W, Dai A, Liu W, Wang B, Wang M, Zheng P. Structures of 2,2,2,2,2-pentaammine-1-aqua-1,2-(μ-imidazolato-N,N')-1-(iminodiacetato-O,O',N)cobalt(III)copper(II) perchlorate trihydrate and 2,2,2,2,2,3,3,3,3,3-decaammine-1,2;1,3-di-(μ-imidazolato-N,N')-1-(iminodiacetato-O,O',N)dicobalt(III)copper(II) perchlorate tetrahydrate. Acta Crystallogr C 1990. [DOI: 10.1107/s0108270189011972] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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2369
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Liu W, Hansen JN. Some chemical and physical properties of nisin, a small-protein antibiotic produced by Lactococcus lactis. Appl Environ Microbiol 1990; 56:2551-8. [PMID: 2119570 PMCID: PMC184764 DOI: 10.1128/aem.56.8.2551-2558.1990] [Citation(s) in RCA: 217] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Nisin is a small gene-encoded antimicrobial protein produced by Lactococcus lactis that contains unusual dehydroalanine and dehydrobutyrine residues. The reactivity of these residues toward nucleophiles was explored by reacting nisin with a variety of mercaptans. The kinetics of reaction with 2-mercaptoethane-sulfonate and thioglycolate indicated that the reaction pathway includes a binding step. Reaction of nisin at high pH resulted in the formation of multimeric products, apparently as a result of intramolecular and intermolecular reactions between nucleophilic groups and the dehydro residues. One of the nucleophiles had a pKa of about 9.8. The unique vinyl protons of the dehydro residues that give readily identifiable proton nuclear magnetic resonances were used to observe the addition of nucleophiles to the dehydro moiety. After reaction with nucleophiles, nisin lost its antibiotic activity and no longer showed the dehydro resonances, indicating that the dehydro groups had been modified. The effect of pH on the solubility of nisin was determined; the solubility was quite high at low pH (57 mg/ml at pH 2) and was much lower at high pH (0.25 mg/ml at pH 8 to 12), as measured before significant pH-induced chemical modification had occurred. High-performance liquid chromatography on a C18 column was an effective technique for separating unmodified nisin from its reaction products. The cyanogen bromide cleavage products of nisin were about 90% less active toward inhibition of bacterial spore outgrowth than was native nisin. These results are consistent with earlier observations, which suggested that the dehydro residues of nisin have a role in the mechanism of antibiotic action, in which they act as electrophilic Michael acceptors toward nucleophiles in the cellular target.
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2370
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Zhou C, Shi H, Liu W, Jin C, Gao H. Antiinflammatoiy effect of essential oil of abies nephrolepis (trautv.) maxim. Eur J Pharmacol 1990. [DOI: 10.1016/0014-2999(90)93813-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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2371
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Liu W, Eliyas A, Petrov L. Influence of feed water vapour on the selective oxidation of ethylene over silver catalyst. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/s0166-9834(00)82149-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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2372
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Qiu MC, Wang JY, Li WS, Qi QL, Shao Q, Liu W, Gao ZH, Li SL. Dynamic study on iliac trabeculae of normal Chinese. Chin Med J (Engl) 1990; 103:363-8. [PMID: 2118051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We studied 41 iliac bone blocks taken by biopsies from normal Chinese who were divided into several groups by age. On the schedule of 3-11-3-5 days, double tetracycline labellings were administered before bone biopsies. Ten microns undecalcified sections were made with Reichert-Jung microtome and analyzed with Zeizz MOP-Videoplan by light and fluorescent microscopy. The results showed that bone formation had a peak value at adolescence and the mean wall thickness decreased gradually with age. Bone dynamics fluctuated with age because of endocrinological changes in the intrinsic environment. The data we obtained may be used as a reference for clinical investigation of various metabolic bone disorders.
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2373
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Zhu XN, Chen R, Kong FH, Liu W. Human leukocyte antigens -A, -B, -C, and -DR and nasopharyngeal carcinoma in northern China. Ann Otol Rhinol Laryngol 1990; 99:286-7. [PMID: 2327697 DOI: 10.1177/000348949009900407] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We observed HLA associations in patients with nasopharyngeal carcinoma from northern China. There was an increased risk of nasopharyngeal carcinoma associated with HLA-B35 and a difference in the HLA association between patients with early- and late-onset disease. The frequency of B35 was significantly higher in patients than in control subjects, especially in early-onset patients (less than 30 years old). Late-onset patients had a higher frequency of DR2 as compared with normal subjects.
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2374
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2375
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Nikaido H, Liu W, Rosenberg EY. Outer membrane permeability and beta-lactamase stability of dipolar ionic cephalosporins containing methoxyimino substituents. Antimicrob Agents Chemother 1990; 34:337-42. [PMID: 2109581 PMCID: PMC171583 DOI: 10.1128/aac.34.2.337] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Some enteric bacteria, such as Enterobacter cloacae, can develop high-level resistance to broad-spectrum cephalosporins by overproducing their chromosomally encoded type I beta-lactamases. This is because these agents are hydrolyzed rapidly at pharmacologically relevant, low (0.1 to 1 microM), concentrations, owing to their high affinity for type I enzymes. In contrast, the more recently developed cephalosporins, with quaternary-nitrogen-containing substituents at the 3 position, show increased efficacy against beta-lactamase-overproducing strains and, indeed, have a much lower affinity for type I enzymes. However, the possible contribution of an improved outer membrane permeability in their increased efficacy has not been studied. We found by proteoliposome swelling assays that cefepime, cefpirome, and E-1040 all penetrated the porin channels of Escherichia coli and E. cloacae much more rapidly than did ceftazidime and at least as rapidly as did cefotaxime. Considering that the influx of anionic compounds such as cefotaxime and ceftazidime will be further retarded in intact cells, owing to the Donnan potential, we expect that the newer compounds will penetrate intact cells 2 to 10 times more rapidly than will cefotaxime and ceftazidime. The kinetic parameters of hydrolysis of these agents by E. cloacae beta-lactamase showed that at 0.1 microM, they were hydrolyzed much more slowly than was cefotaxime and at about the same rate as or a lower rate than was ceftazidime. The combination of these two effects explains nearly quantitatively why these newer agents are more effective against some of the beta-lactamase-overproducing gram-negative bacteria.
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2376
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Gottlieb S, Liu W, Renken RL, Sugar RL, Toussaint D. QCD thermodynamics with eight time slices. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1990; 41:622-625. [PMID: 10012368 DOI: 10.1103/physrevd.41.622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2377
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Hayter AJ, Liu W. Power assessment for tests of the equality of several proportions. COMMUN STAT-THEOR M 1990. [DOI: 10.1080/03610929008830184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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2378
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Gottlieb S, Liu W, Renken RL, Sugar RL, Toussaint D. Four-flavor QCD with intermediate- and light-mass quarks. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1989; 40:2389-2409. [PMID: 10012076 DOI: 10.1103/physrevd.40.2389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2379
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Curtin PT, Liu DP, Liu W, Chang JC, Kan YW. Human beta-globin gene expression in transgenic mice is enhanced by a distant DNase I hypersensitive site. Proc Natl Acad Sci U S A 1989; 86:7082-6. [PMID: 2780563 PMCID: PMC297998 DOI: 10.1073/pnas.86.18.7082] [Citation(s) in RCA: 93] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Several lines of evidence suggest that erythroid-specific DNase I hypersensitive sites (HS) located far upstream of the human beta-globin gene are important in regulating beta-globin gene expression. We used the polymerase chain reaction technique to amplify and clone an 882-base-pair DNA fragment spanning one of these HS, designated HSII, which is located 54 kilobases upstream of the beta-globin gene. The cloned HSII fragment was linked to a human beta-globin gene in either the genomic (HSII-beta) or antigenomic (HSII-beta) orientation. These two constructs and a beta-globin gene alone (beta) were injected into fertilized mouse eggs, and expression was analyzed in liver and brain from day-16 transgenic fetuses. Five of 7 beta-transgenic fetuses expressed human beta-globin mRNA, but the level of expression per gene copy was low, ranging from 0.93 to 22.4% of mouse alpha-globin mRNA (average 9.9%). In contrast, 11 of 12 HSII-beta transgenic fetuses expressed beta-globin mRNA at levels per gene copy ranging from 31.3 to 336.6% of mouse alpha-globin mRNA (average 139.5%). Only three fetuses containing intact copies of the HSII-beta construct were produced. Two of three expressed human beta-globin mRNA at levels per gene copy of 179.2 and 387.1%. Expression of human beta-globin mRNA was tissue-specific in all three types of transgenic fetuses. These studies demonstrate that a small DNA fragment containing a single erythroid-specific HS can stimulate high-level human beta-globin gene expression in transgenic mice.
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2380
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Zhou CC, Gao HB, Sun XB, Shi HB, Liu W, Yuan HN, Wang ZX. [Anti-inflammatory and anti-allergic action of aloperine]. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1989; 10:360-5. [PMID: 2533795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Aloperine, an alkaloid isolated from Sophora alopecuroides L, showed a marked suppressive effect on the swelling of the rat's hind paw induced by injecting carrageenin, macostatin, PGE2, histamine, 5-HT, on the rat's scald oedema induced by scalding its hind paw, and on the increased permeability of capillaries caused by histamine and the leukocytic migratory response. The swelling induced by injecting carrageenin into the hind paw of adrenolectomized rats was still significantly inhibited. Noticeably, aloperine reduced the content of PGE and histamine in the exudate formed after injecting carrageenin and dextran into the rat's hind paw, and increased the stability of red cell membranes, the activity of catalase (CAT) in hepatic tissue of mice, and reduced the content of malondialdehyde (MDA) in hepatic tissue of intoxicated mice. It had no apparent effect either on the activity of superoxide dismutase (SOD) in mice serum or on the phagocytosis of the monocyte-macrophage system, or on Forssman cutaneous vasculitis and the content of immune complex in serum of rats with Arthus reaction. But it had certain inhibitory effect on the PCA reaction and significant inhibitory effect upon such allergic reaction as Arthus reaction, reversible passive Arthus reaction, the delayed hypersensitivity reaction induced by tuberculin in rats, and adjuvant arthritis.
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2381
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Holzer KP, Liu W, Hammes GG. Molecular cloning and sequencing of chicken liver fatty acid synthase cDNA. Proc Natl Acad Sci U S A 1989; 86:4387-91. [PMID: 2734291 PMCID: PMC287274 DOI: 10.1073/pnas.86.12.4387] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The complete amino acid sequence of chicken liver fatty acid synthase [acyl-CoA:malonyl-CoA C-acyltransferase (decarboxylating, oxoacyl- and enoyl-reducing, and thioester-hydrolyzing), EC 2.3.1.85] has been determined from the corresponding cDNA sequence. A 5.3-kilobase-pair (kbp) region of cDNA coding for chicken fatty acid synthase has been cloned and sequenced that is contiguous to the 2.3-kbp region previously sequenced [Yuan, Z., Liu, W. & Hammes, G.G. (1988) Proc. Natl. Acad. Sci. USA 85, 6328-6331]. The cDNA codes for the remaining 1677 amino acids of the previously unsequenced region of the protein. The amino acid sequence contains peptides known to be associated with the NADPH binding site of the enoylreductase active center, the acetyl/malonyltransacylase active site, the "waiting" site containing cysteine, and a pyridoxal 5'-phosphate binding site. Locations of the NADPH binding site of the beta-ketoacylreductase active site and of the dehydratase active site are proposed on the basis of protein sequence homologies to catalytic sites in other enzymes. The molecular weight of the complete polypeptide chain is 267,288. A linear functional map of the chicken fatty acid synthase derived from its primary sequence is presented.
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2382
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Liu W, Jiao KR, Jin CH. [Dynamic changes of the plasma prekallikrein activity in patients with acute myocardial infarction]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1989; 17:130-2, 189. [PMID: 2598778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The activity of the plasma prekallikrein was assayed by using dextran sulfate as activator and chromogenic compound substance Na-benzoyl-DL-arginine-4-nitroanilid-hydrochloride (BAPNA) as substrate. The dynamic changes of the plasma prekallikrein activity were observed in 22 patients with acute myocardial infarction (AMI) at different period. The correlation between plasma prekallikrein activity and serum CPK activity were analysed in part of the patients. The results indicate that the plasma prekallikrein activity decreased significantly in AMI, especially on the third day after onset. The decrease of plasma prekallikrein and increase of serum CPK were correlated negatively. The results indicate that the chromogenic compound substance BAPNA can be used to determine the activity of plasma prekallikrein. The kinin system was activated by certain factors in AMI, causing the decrease of plasma prekallikrein and increase of bradykinin.
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2383
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Lu ZL, Zhang GX, Liu W. [Evaluation of various parameters in the differential diagnosis of Cushing's disease and Cushing's syndrome caused by adrenal adenoma]. ZHONGHUA NEI KE ZA ZHI 1989; 28:28-31, 62. [PMID: 2737034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Evaluation of the clinical and biochemical parameters for differential diagnosis of two types of Cushing's syndrome, pituitary-dependent Cushing's disease and adrenal adenoma, was studied with analysis of the histories of 79 cases of Cushing's disease and 23 cases of adrenal adenoma. The data show that the symptoms, signs and the routine biochemical analyses were not significantly different between two groups. High-dose dexamethasone suppression test had about 90% coincidence rate in the differential diagnosis with 24-hour urine free cortisol (UFC), which was better than 24-hour urine 17-OHCS. Interestingly, low-dose dexamethasone test was highly valuable and the 24-hour urine 17-KS quite helpful in the differential diagnosis of two types of Cushing's syndrome. Serum N-POMC measurement was the most valuable among the parameters, because there was no overlap between the two groups of Cushing's syndrome.
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2384
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Gottlieb S, Liu W, Renken RL, Sugar RL, Toussaint D. Fermion-number susceptibility in lattice gauge theory. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1988; 38:2888-2896. [PMID: 9959463 DOI: 10.1103/physrevd.38.2888] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2385
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Margolis LH, Wagenaar AC, Liu W. The effects of a mandatory child restraint law on injuries requiring hospitalization. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1988; 142:1099-103. [PMID: 3177307 DOI: 10.1001/archpedi.1988.02150100093035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Using data on all inpatients in 16 Michigan hospitals from 1980 through 1985, the clinical effects of a mandatory child restraint law were examined. Time-series analytic techniques revealed a 36% decline in hospitalization for all injuries, with a 25% decline for head injuries, and a 20% decline for extremity injuries for children younger than 4 years. In addition, length of stay declined for children hospitalized secondary to motor vehicle crashes. This study confirms the effectiveness of the child restraint law in Michigan, previously demonstrated by analyses of police records. Current hospital databases may be able to serve as one component for the implementation of comprehensive injury surveillance systems.
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2386
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Gottlieb S, Liu W, Renken RL, Sugar RL, Toussaint D. Hadron masses with two quark flavors. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1988; 38:2245-2265. [PMID: 9959379 DOI: 10.1103/physrevd.38.2245] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2387
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Yuan ZY, Liu W, Hammes GG. Molecular cloning and sequencing of DNA complementary to chicken liver fatty acid synthase mRNA. Proc Natl Acad Sci U S A 1988; 85:6328-31. [PMID: 2842766 PMCID: PMC281963 DOI: 10.1073/pnas.85.17.6328] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The cDNA corresponding to 4.18 kilobases (kb) of the mRNA of chicken liver fatty acid synthase has been cloned and sequenced. The cDNA corresponds to the 3' end of the mRNA and consists of a 1.87-kb noncoding tail and a 2.31-kb region encoding 769 amino acids of the C terminus of the enzyme. The thioesterase at the C terminus, preceded by the acyl carrier protein, can be identified from known amino acid sequences. However, the identity of the enzymes N terminal to the acyl carrier protein could not be ascertained. The partial amino acid sequence of the chicken liver fatty acid synthase shows greater than 70% similarity with the rat mammary gland enzyme.
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2388
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Huott PA, Liu W, McRoberts JA, Giannella RA, Dharmsathaphorn K. Mechanism of action of Escherichia coli heat stable enterotoxin in a human colonic cell line. J Clin Invest 1988; 82:514-23. [PMID: 2457034 PMCID: PMC303542 DOI: 10.1172/jci113626] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Escherichia coli heat stable enterotoxin (STa) caused Cl- secretion across T84 cell monolayers in a dose-dependent manner only when applied to the apical membrane surface and not when applied to the basolateral surface. Measurement of cAMP, cGMP, and free cytosolic Ca2+ in response to STa suggested that cGMP alone mediated the Cl- secretory response. Studies utilizing blockers of the Na+,K+-ATPase pump, a Na+,K+,Cl- cotransport system, a K+ channel, and a Cl- channel suggest that all of them participate in the Cl- secretory process induced by STa. The results suggest that the Cl- secretory response induced by STa is mediated by cGMP after the enterotoxin binds to its receptor on the apical membrane. The enterotoxin, by increasing cGMP, opens a K+ channel on the basolateral membrane as well as a Cl- channel on the apical membrane. The activation of these ion exit mechanisms, together with activations of the Na+,K+,Cl- cotransporter and the Na+,K+-ATPase pump drives Cl- exit through the Cl- channel on the apical membrane.
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2389
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Liu W, Wang DX, Lu GS, Han JS, Chai SH, Fan L. [Solid-phase peptide synthesis of a cardioexcitatory peptide and its analog]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1988; 23:262-6. [PMID: 3176978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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2390
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Liu W, Tsou CL. Activity change during unfolding of bovine pancreatic ribonuclease A in guanidine. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 916:455-64. [PMID: 3689804 DOI: 10.1016/0167-4838(87)90192-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Bovine pancreatic ribonuclease A loses almost completely its activity in 2-3 M guanidine, whereas only very slight conformational changes can be detected when following its unfolding by changes in its intrinsic fluorescence at 305 nm and ultraviolet absorbance at 287 nm. Reactivation on diluting out the denaturant is a time-dependent process, indicating that the inactivation is not due to inhibition by a reversible association of the enzyme with guanidine. The kinetic method of following the substrate reaction, in the presence of the denaturant previously proposed for use in the study of rapid inactivation reactions (Tian, W.X. and Tsou, C.-L. (1982) Biochemistry 21, 1028-1032), is applied to examine the inactivation rates of this enzyme during guanidine denaturation, and these have been compared with the unfolding rates as followed by fluorescence and absorbance changes. It is shown that during the unfolding of this enzyme in guanidine, the inactivation of the enzyme occurs within the dead time of mixing in a stopped-flow apparatus and is at least several orders of magnitude faster than the unfolding reaction as detected by the optical parameters. It appears that, as in the case of creatine kinase reported previously, the active site of a small enzyme stabilized by multiple disulfide linkages, such as ribonuclease A, is also situated in a region which is much more liable to being perturbed by denaturants than is the molecule as a whole.
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2391
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Liu W, Tsou CL. Kinetics of reactivation during refolding of guanidine-denatured pancreatic ribonuclease A. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 916:465-73. [PMID: 2825794 DOI: 10.1016/0167-4838(87)90193-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The method aforementioned (Liu, W. and Tsou, C.L. (1987) Biochim. Biophys. Acta 916, 455-464) for the study of the kinetics of irreversible modification of enzyme activity has been applied to the reactivation of guanidine-denatured ribonuclease A, by following the hydrolysis of cyclic CMP during refolding upon diluting a guanidine-denatured enzyme with a substrate-containing buffer. Appropriate equations have been derived to deal with the kinetics of the substrate reaction during the course of activation, while the product formed, 3'CMP, is a competitive inhibitor. When the overall process consists of multiple first-order reactions, the individual rate constants could be obtained by suitable semilogarithmic plots. Moreover, in certain cases, it can be distinguished from the shapes of the plots, whether the overall process consists of parallel or consecutive first-order reactions. The kinetics for the reactivation reaction has been compared to that for the refolding of the substrate binding site, as indicated by complex formation with the competitive inhibitor, 2'CMP, and for the refolding of the molecule as a whole. At pH 6.0 and 25 degrees C, only monophasic first-order reactions could be detected by manual mixing for both the reactivation and the refolding processes. At lower temperatures (0-10 degrees C), both processes consist of two first-order reactions. In all cases, the same rate constants have been obtained for the refolding and reactivation reactions.
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2392
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Gottlieb S, Liu W, Toussaint D, Renken RL, Sugar RL. Empirical study of the hybrid-molecular-dynamics approach to the simulation of QCD. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1987; 36:3797-3803. [PMID: 9958168 DOI: 10.1103/physrevd.36.3797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2393
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Gottlieb S, Liu W, Toussaint D, Renken RL, Sugar RL. Quark-number susceptibility of high-temperature QCD. PHYSICAL REVIEW LETTERS 1987; 59:2247-2250. [PMID: 10035494 DOI: 10.1103/physrevlett.59.2247] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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2394
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Gottlieb S, Liu W, Toussaint D, Renken RL, Sugar RL. Hadronic screening lengths in the high-temperature plasma. PHYSICAL REVIEW LETTERS 1987; 59:1881-1884. [PMID: 10035358 DOI: 10.1103/physrevlett.59.1881] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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2395
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Gottlieb S, Liu W, Toussaint D, Renken RL, Sugar RL. Estimating the chiral-symmetry-restoration temperature in two-flavor QCD. PHYSICAL REVIEW LETTERS 1987; 59:1513-1516. [PMID: 10035255 DOI: 10.1103/physrevlett.59.1513] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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2396
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Gottlieb S, Liu W, Toussaint D, Renken RL, Sugar RL. Chiral-symmetry breaking in lattice QCD with two and four fermion flavors. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1987; 35:3972-3980. [PMID: 9957661 DOI: 10.1103/physrevd.35.3972] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2397
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Sun IL, Garcia-Cañero R, Liu W, Toole-Simms W, Crane FL, Morré DJ, Löw H. Diferric transferrin reduction stimulates the Na+/H+ antiport of HeLa cells. Biochem Biophys Res Commun 1987; 145:467-73. [PMID: 3036130 DOI: 10.1016/0006-291x(87)91344-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Proton release from HeLa cells is stimulated by external oxidants for the transplasmalemma electron transport enzymes. These oxidants, such as ferricyanide and diferric transferrin, also stimulate cell growth. We now present evidence that proton release associated with the reduction of ferricyanide and diferric transferrin is through the Na+/H+ antiport. The stoichiometry of H+/e- release with diferric transferrin is over 50 to 1, which is greater than expected for oxidation of a protonated transmembrane electron carrier. Diferric transferrin induced proton release depends on external sodium and is inhibited by amiloride. Proton release is also inhibited when diferric transferrin reduction is inhibited by apotransferrin. A tightly coupled association between the redox system and the antiport is shown by sodium dependence and amiloride inhibition of diferric transferrin reduction. The results indicate a new role for ferric transferrin in growth stimulation by activation of the sodium-proton antiport.
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2398
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Gottlieb S, Liu W, Toussaint D, Renken RL, Sugar RL. Hybrid-molecular-dynamics algorithms for the numerical simulation of quantum chromodynamics. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1987; 35:2531-2542. [PMID: 9957958 DOI: 10.1103/physrevd.35.2531] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2399
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Gottlieb S, Liu W, Toussaint D, Sugar RL. Testing an exact algorithm for simulation of fermionic QCD. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1987; 35:2611-2614. [PMID: 9957970 DOI: 10.1103/physrevd.35.2611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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2400
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Sun YB, Wu YW, Liu W, Yuan D. Effect of (D-Trp6, Pro9-NEt)-GnRH on the function and ultrastructure of pituitary and testis in male rats. Contraception 1987; 35:79-87. [PMID: 3552402 DOI: 10.1016/0010-7824(87)90053-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Groups of ten adult male Wistar rats were treated chronically with GnRH agonist for different durations. The responses of pituitary and testis to GnRH agonist were evaluated by serum and testicular testosterone, serum and pituitary LH, and testicular LH receptors. Testicular testosterone and LH receptors were decreased very significantly under our experimental regimen, irrespective of the duration of the treatment Serum testosterone levels were reduced after 10 and 15 injections, but only rats receiving 10 injections showed a significant increase in serum LH levels and decrease of pituitary LH content. The type II gonadotropes of the pars distalis of pituitary were increased in number but showed a higher degree of dilated smooth endoplasmic reticulum with few secretory granules. Many large lipid droplets appeared in the cytoplasms of the Leydig cells. Degenerative changes were observed in most seminiferous tubules following GnRH agonist treatment. Obvious abnormal acrosome and nuclear caps of some spermatids were also observed. The functional changes caused by GnRH agonist coincided with their ultrastructural appearance.
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