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Ugolini F, Adélaïde J, Charafe-Jauffret E, Nguyen C, Jacquemier J, Jordan B, Birnbaum D, Pébusque MJ. Differential expression assay of chromosome arm 8p genes identifies Frizzled-related (FRP1/FRZB) and Fibroblast Growth Factor Receptor 1 (FGFR1) as candidate breast cancer genes. Oncogene 1999; 18:1903-10. [PMID: 10086345 DOI: 10.1038/sj.onc.1202739] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Deletions and amplifications are frequent alterations of the short arm of chromosome 8 associated with various types of cancers, including breast cancers. This indicates the likely presence of tumor suppressor genes and oncogenes. In the present study, we have used the expressed sequence tag (EST) map of 8p11-21 to assemble a set of available cDNAs representing genes from this region. DNA arrays were prepared for expression analysis and search for genes potentially involved in breast cancer. Underexpresion in tumoral breast cells (versus normal breast) was observed for 15 transcripts. Among these, the Frizzled-related gene FRP1/FRZB, was turned off in 78% of breast carcinomas, suggesting that the lack of its product may be associated with malignant transformation. Overexpression in tumoral breast cells was observed for 13 genes. The FGFR1 gene, that encodes a tyrosine kinase receptor for members of the fibroblast growth factor family, was identified as a good candidate for one amplification unit. Taken together, our results demonstrate that such a strategy can rapidly identify genes with an altered pattern of expression and provide candidate genes for malignancies.
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302
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Cai J, Chu JC, Recine D, Sharma M, Nguyen C, Rodebaugh R, Saxena VA, Ali A. CT and PET lung image registration and fusion in radiotherapy treatment planning using the chamfer-matching method. Int J Radiat Oncol Biol Phys 1999; 43:883-91. [PMID: 10098445 DOI: 10.1016/s0360-3016(98)00399-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE We present a validation study of CT and PET lung image registration and fusion based on the chamfer-matching method. METHODS AND MATERIALS The contours of the lung surfaces from CT and PET transmission images were automatically segmented by the thresholding technique. The chamfer-matching technique was then used to register the extracted lung surfaces. Arithmetic means of distance between the two data sets of the pleural surfaces were used as the cost function. Matching was then achieved by iteratively minimizing the cost function through three-dimensional (3D) translation and rotation with an optimization method. RESULTS Both anatomic thoracic phantom images and clinical patient images were used to evaluate the performance of our registration system. Quantitative analysis from five patients indicates that the registration error in translation was 2-3 mm in the transverse plane, 3-4 mm in the longitudinal direction, and about 1.5 degree in rotation. Typical computing time for chamfer matching is about 1 min. The total time required to register a set of CT and PET lung images, including contour extraction, was generally less than 30 min. CONCLUSION We have implemented and validated the chamfer-matching method for CT and PET lung image registration and fusion. Our preliminary results show that the chamfer-matching method for CT and PET images in the lung area is feasible. The described registration system has been used to facilitate target definition and treatment planning in radiotherapy.
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303
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Imbert MC, Nguyen VK, Granjeaud S, Nguyen C, Jordan BR. 'LABNOTE', a laboratory notebook system designed for academic genomics groups. Nucleic Acids Res 1999; 27:601-7. [PMID: 9862986 PMCID: PMC148221 DOI: 10.1093/nar/27.2.601] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have developed a relational laboratory database system, adapted to the daily book-keeping needs of laboratories that must keep track of information acquired on hundreds or thousands of clones in an effective and user-friendly fashion. Data, whether final or related to experiments in progress, can be accessed in many different ways, e.g. by clone name, by gene, by experiment or through DNA sequence. Updating, import and export of results is made easier by specially developed tools. This system, in network version, serves several groups in our Institute and (over the Internet) elsewhere, and is instrumental in collaborative studies based on expression profiling. It can be used in many similar situations involving progressiveaccumulation of information on sets of clones or related objects.
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304
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Huang T, Nguyen C, Shott S, Gitelis S. 2303 Long-term outcome of combined modality therapy for soft-tissue sarcomas and the prognostic validity of the 1998 AJCC stage groupings. Int J Radiat Oncol Biol Phys 1999. [DOI: 10.1016/s0360-3016(99)90571-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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305
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Lin YS, Nguyen C, Mendoza JL, Escandon E, Fei D, Meng YG, Modi NB. Preclinical pharmacokinetics, interspecies scaling, and tissue distribution of a humanized monoclonal antibody against vascular endothelial growth factor. J Pharmacol Exp Ther 1999; 288:371-8. [PMID: 9862791] [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
Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis and in pathological processes such as tumor growth, rheumatoid arthritis, and ocular neovascularization. A recombinant humanized monoclonal antibody (rhuMAb), rhuMAb VEGF, has been developed to inhibit the effects of VEGF in the treatment of solid tumors. Intravenous and s.c. pharmacokinetic studies were conducted in mice, rats, and cynomolgus monkeys. In addition, the tissue distribution of i.v. 125I-rhuMAb VEGF was investigated in rabbits. At a dose of approximately 10 mg/kg, the clearance of rhuMAb VEGF from the serum was 15.7 ml/day/kg in mice, 4.83 ml/day/kg in rats, and 5.59 ml/day/kg in cynomolgus monkeys, and the terminal half-life ranged from 6 to 12 days in all species. After s.c. administration, rhuMAb VEGF had a bioavailability of 69% in rats and 100% in mice and cynomolgus monkeys. Pharmacokinetic data in mice, rats, and cynomolgus monkeys were used to predict the pharmacokinetics of rhuMAb VEGF using allometric scaling in humans. The predicted serum clearance of rhuMAb VEGF in humans was 2.4 ml/day/kg and the terminal half-life was 12 days. Two hours after i.v. bolus administration of 125I-rhuMAb VEGF in rabbits, trichloroacetic acid-precipitable radioactivity was noted primarily in the plasma, with lesser amounts in highly perfused tissues such as kidneys, testes, spleen, heart, and lungs. At 48 h after dosing, trichloroacetic acid-precipitable radioactivity was noted in plasma with minimal distribution to testes, bladder, heart, lungs, and kidneys. Tissue distribution and pharmacokinetic data indicate that rhuMAb VEGF is cleared slowly and distributes to specific sites in the body.
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306
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Zelphati O, Nguyen C, Ferrari M, Felgner J, Tsai Y, Felgner PL. Stable and monodisperse lipoplex formulations for gene delivery. Gene Ther 1998; 5:1272-82. [PMID: 9930330 DOI: 10.1038/sj.gt.3300707] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A stable single vial lipoplex formulation has been developed that can be stored frozen without losing either biological activity or physical stability. This formulation was identified by systematically controlling several formulation variables and without introducing either stabilizers or surfactants. Analytical assays were used to unambiguously characterize the formulations. The critical formulation parameters were: (1) the size of the cationic liposomes; (2) the rate and method of DNA and cationic liposome mixing; and (3) the ionic strength of the suspending vehicle. The mixing conditions were precisely controlled by using a novel, specially designed continuous flow pumping system in which the DNA and liposome solutions were mixed at the junction of a T-connector. Homogenous cationic liposome preparations were prepared by extrusion in two different size ranges of either 400 or 100 nm. Extruded liposomes produced more monodisperse and physically stable lipoplex formulations than unextruded liposomes, but the formulations prepared with 100 nm liposomes were less active in in vitro transfection assays than either the 400 nm or unextruded liposomes. Low ionic strength and 5% sorbitol were required for the lipoplex formulations to survive freezing and thawing. A frozen lipoplex formulation stored for more than a year maintained its biological activity. These results have broad implications for the pharmaceutical development of lipoplex formulations for gene delivery.
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307
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Nguyen C, Do D. Letter to the Editor. ADSORPT SCI TECHNOL 1998. [DOI: 10.1177/026361749801600808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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308
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Blanco J, Nguyen C, Callebaut C, Jacotot E, Krust B, Mazaleyrat JP, Wakselman M, Hovanessian AG. Dipeptidyl-peptidase IV-beta--further characterization and comparison to dipeptidyl-peptidase IV activity of CD26. EUROPEAN JOURNAL OF BIOCHEMISTRY 1998; 256:369-78. [PMID: 9760177 DOI: 10.1046/j.1432-1327.1998.2560369.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Dipeptidyl peptidase IV-beta (DPP IV-beta) is a novel protein which shows a peptidase activity similar to the T-cell-activation antigen CD26. To further characterize this DPP IV-beta and confirm its cell surface expression, we have developed a purification strategy using the CD26- cell line C8166. The purification process includes biotinylation of cell surface proteins before preparation of cell extracts and processing by gel-filtration, ion-exchange and lectin chromatographies. Consistent with the molecular mass of DPP IV-beta estimated by gel-filtration chromatography, the final purified fraction, manifesting a typical DPP IV activity, showed a major biotinylated 75-80-kDa band in SDS/PAGE, thus suggesting the monomeric nature of this enzyme. Kinetic parameters of DPP IV-beta and the sensitivity to a new family of irreversible DPP IV inhibitors, were studied in comparison to CD26. Both enzymes followed a Michaelis kinetics with different Km values for Gly-Pro-NH-Np (NH-Np, para-nitroanilide) hydrolysis (0.28+/-0.05 mM and 0.12+/-0.02 mM). More significant differences were observed in the sensitivity to inhibitors, which exerted a much higher activity on CD26 than on DPP IV-beta. These differences permitted us to study DPP IV-beta expression in CD26-expressing cells, showing the expression of this new enzyme in all lymphoid cells tested, and a rapid enhancement in phytohemagglutinin-stimulated or protein-A-stimulated peripheral blood mononuclear cells. Our results indicate that, although DPP IV-beta and CD26 are coexpressed and manifest a typical DPP IV activity, there are distinct features in their catalytic activities that may confer to each enzyme a complementary role in peptide processing.
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309
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Nguyen C. A piece of my mind. The veteran. JAMA 1998; 280:692. [PMID: 9728626 DOI: 10.1001/jama.280.8.692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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310
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Glienke J, Sobanov Y, Brostjan C, Steffens C, Nguyen C, Lehrach H, Hofer E, Francis F. The genomic organization of NKG2C, E, F, and D receptor genes in the human natural killer gene complex. Immunogenetics 1998; 48:163-73. [PMID: 9683661 DOI: 10.1007/s002510050420] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Interactions of natural killer cell receptors with their cognate ligands play a major role in regulating NK cell function. The NKG2 gene family encodes several highly similar proteins, which are known to form heterodimers with the CD94 receptor. These dimers play a role in the inhibition as well as the activation of NK cells. We have analyzed the gene structures of the NKG2C, D, E, and F genes, and determined their genomic organization. Restriction mapping and sequencing revealed the four genes to be closely linked to one another, and of the same transcriptional orientation. An exon duplication within the NKG2C and E genes was identified, although the duplicated version of this exon has not yet been found in mRNA sequences. The NKG2C, E, and F genes, despite being highly similar, are variable at their 3' ends. We show that NKG2C consists of six exons, whereas NKG2E has seven, and the splice acceptor site for the seventh exon occurs in an Alu repeat. NKG2F consists of only four exons and part of exon IV is in some cases spliced to the 5' end of the NKG2D transcript. NKG2D has only a low similarity to the other NKG2 genes.
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311
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Nguyen C, Blanco J, Mazaleyrat JP, Krust B, Callebaut C, Jacotot E, Hovanessian AG, Wakselman M. Specific and irreversible cyclopeptide inhibitors of dipeptidyl peptidase IV activity of the T-cell activation antigen CD26. J Med Chem 1998; 41:2100-10. [PMID: 9622551 DOI: 10.1021/jm970640l] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The dipeptidyl peptidase IV (DPP IV) activity of CD26 is characterized by its post-proline-cleaving capacity that plays an important but not yet understood role in biological processes. Here we describe a new family of specific and irreversible inhibitors of this enzyme. Taking into account the substrate specificity of DPP IV for P2-P1><-P1' cleavage, we have designed and synthesized cyclopeptides c[(alphaH2N+)-Lys-Pro-Aba-(6-CH2-S+R2)-Glyn] 2TFA- (Aba = 3-aminobenzoic acid, R = alkyl) possessing a proline at the P1 position and a lysine in the P2 position, which allows the closing of the cycle on its side chain. These molecules show a free N-terminus, necessary for binding to the CD26 catalytic site, and a latent quinoniminium methide electrophile, responsible for inactivation. Treatment of c[alphaZ-Lys-Pro-Aba-(6-CH2-OC6H5)-Glyn], obtained by peptide synthesis in solution, with R2S/TFA simutaneously cleaved the Z protecting group and the phenyl ether function and led to a series of cyclopeptide sulfonium salts. These cyclopeptides inhibited rapidly and irreversibly the DPP IV activity of CD26, with IC50 values in the nanomolar range. Further studies were carried out to investigate the effect of the modification of the ring size (n = 2 or 4) and the nature of the sulfur substituents (R = Me, Bu, Oct). Cycle enlargement improved the inhibitory activity of the methylsulfonio cyclopeptide, whereas the increase of the alkyl chain length on the sulfur atom had no apparent effect. Other aminopeptidases were not inhibited, and a much weaker activity was observed on a novel isoform of DPP IV referred to as DPP IV-beta. Thus, this new family of irreversible inhibitors of DPP IV is highly specific to the peptidase activity of CD26.
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312
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Zembower TR, Noskin GA, Postelnick MJ, Nguyen C, Peterson LR. The utility of aminoglycosides in an era of emerging drug resistance. Int J Antimicrob Agents 1998; 10:95-105. [PMID: 9716286 DOI: 10.1016/s0924-8579(98)00033-8] [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: 01/17/2023]
Abstract
As the problem of global antibiotic resistance continues to worsen, aminoglycosides have assumed increasing importance in clinical practice. Their broad antimicrobial spectrum, rapid bactericidal action, and ability to act synergistically with other drugs have made them especially useful in the treatment of serious nosocomial infections. However, as with other drugs, their overuse and misuse leads to the development of resistance in important microbial pathogens. The appropriate use of the aminoglycosides is essential to assure their continued efficacy. Therefore, physicians must familiarize themselves with both the clinical indications and the limitations of these drugs if they are to remain efficacious in the years to come.
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313
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Peleg S, Nguyen C, Woodard BT, Lee JK, Posner GH. Differential use of transcription activation function 2 domain of the vitamin D receptor by 1,25-dihydroxyvitamin D3 and its A ring-modified analogs. Mol Endocrinol 1998; 12:525-35. [PMID: 9544988 DOI: 10.1210/mend.12.4.0083] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Analogs of 1,25-dihydroxyvitamin D3 (1,25D3) can be used to elucidate details of vitamin D receptor (VDR) activation. The A ring-modified analog, (TN-2) has 15-fold less affinity for VDR, but its transcriptional activity is diminished 1000-fold. Likewise, the ability of TN-2 to induce a protease-resistant conformation in VDR is 1/1000 that of 1,25D3. The stability of the VDR-TN-2 complexes is also significantly lower than VDR-1,25D3 complexes. Mapping the VDR-binding site of TN-2 showed that it had a significantly greater requirement for transcription activation function 2 (AF-2) residues than 1,25D3 did. These results suggest that the increased requirement for AF-2 residues that was induced by the A ring modifications is associated with diminished receptor activation. To determine whether restoring the potency of TN-2 by additional structural modifications would change the requirements for AF-2 residues, we synthesized hybrid analogs with 1beta-hydroxymethyl-3-epi groups and with dimethyl groups at positions 26 and 27 of the side chain, without or with a double bond between CD ring positions 16 and 17. We found that the side chain modification enhanced transcriptional activity 150-fold, increased the ability of the receptor to form a protease-resistant conformation 100-fold, and stabilized the VDR-analog complexes. The addition of the 16-ene group further reduced the analog's dissociation rate and increased its potency in the protease assays. These functional changes in the hybrid analogs were associated with a significant reduction in interaction with AF-2 residues. We conclude that there is an inverse relationship between analogs' potencies and their interaction with AF-2 residues of VDR.
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314
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Camerini V, Sydora BC, Aranda R, Nguyen C, MacLean C, McBride WH, Kronenberg M. Generation of intestinal mucosal lymphocytes in SCID mice reconstituted with mature, thymus-derived T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1998; 160:2608-18. [PMID: 9510158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Transfer of peripheral lymph node lymphocytes to SCID mice leads to the long term establishment of mucosal T lymphocytes within the epithelium and lamina propria of the small and large intestines. Analysis of engrafted intraepithelial lymphocytes (IEL) showed that they had acquired a surface phenotype that in several respects is typical of IEL. In addition, the functional profile of engrafted IEL derived from lymph node T cells was similar to that of normal IEL; as the donor-derived T cells exhibited a strong cytolytic activity, a poor proliferative response to mitogenic stimuli, and a tendency to home and expand specifically in the intestine upon transfer to secondary SCID recipients. Optimal engraftment of intestinal T cells required bacterial flora, as the number of lymphocytes was greatly reduced in SCID recipients with a reduced flora. These results demonstrate that mature, thymus-derived T cells can migrate to the intestine and become functionally specialized to the intestinal milieu. The acquisition of phenotypic markers characteristic of the intestinal microenvironment by engrafted cells suggests that T cell migration of lymphocytes to the SCID intestine is not aberrant, but it may reflect processes that are ongoing in immunocompetent mice. Furthermore, these data suggest that the homing and/or expansion of typical, thymus-derived T cells in the intestine may be driven by luminal Ags such as those derived from bacterial flora.
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315
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Lewis CM, Smith AK, Nguyen C, Kamen BA. PMA alters folate receptor distribution in the plasma membrane and increases the rate of 5-methyltetrahydrofolate delivery in mature MA104 cells. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1401:157-69. [PMID: 9531971 DOI: 10.1016/s0167-4889(97)00126-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
MA104 cells (a monkey kidney cell line) can internalize 5-methyltetrahydrofolate via a receptor mediated process termed potocytosis. Uptake is initiated by binding to an external folate receptor which cycles to an internal, but membrane bound compartment. These two pools can be measured by determining the amount of [3H]ligand removed by an acid-saline wash, i.e. acid labile and acid resistant pools. When assayed in confluent nonmitotic cells, 2/3 of the folate receptor pool is located in an internal (acid resistant) compartment, but phorbol 12-myristate 13-acetate (PMA) causes a shift such that 65-75% of the receptor pool resides on the surface of the plasma membrane. This new steady state is likely the result of an increased rate of receptor movement. In addition, PMA increases the rate of 5-methyl[3H]tetrahydrofolate delivery to the cytoplasm 1.8 fold. Using known inhibitors of potocytosis, we were able to show that the increased rate of delivery is receptor mediated. Comparison of the time courses of the PMA effects on folate receptor redistribution assessed by membrane binding of [3H]folic acid and 5-methyl[3H]tetrahydrofolate delivery to the cytoplasm suggests that PMA may be activating more than one protein kinase C independent signal transduction pathway. PMA is the first reported positive modulator of receptor mediated folate uptake.
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316
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Nguyen C. Sensitive Detection of the Effects of Aging in Senescent Rat Myocardium With Ultrasonic Tissue Characterization. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(97)88080-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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317
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Jones PC, Silverman BG, Athanasoulis M, Drucker D, Goldberg H, Marsh J, Nguyen C, Ravichandar D, Reis L, Rind D, Safran C. Nationwide telecare for diabetics: a pilot implementation of the HOLON architecture. Proc AMIA Symp 1998:346-50. [PMID: 9929239 PMCID: PMC2232089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
This paper presents results from a demonstration project of nationwide exchange of health data for the home care of diabetic patients. A consortium of industry, academic, and health care partners has developed reusable middleware components integrated using the HOLON architecture. Engineering approaches for multi-organization systems development, lessons learned in developing layered object-oriented systems, security and confidentiality considerations, and functionality for nationwide telemedicine applications are discussed.
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318
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Nguyen C. [The risk of suicide and its prevention in the elderly]. SOINS; LA REVUE DE REFERENCE INFIRMIERE 1997:41-4. [PMID: 9479220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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319
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Ayyavoo V, Nagashunmugam T, Boyer J, Mahalingam S, Fernandes LS, Le P, Lin J, Nguyen C, Chattargoon M, Goedert JJ, Friedman H, Weiner DB. Development of genetic vaccines for pathogenic genes: construction of attenuated vif DNA immunization cassettes. AIDS 1997; 11:1433-44. [PMID: 9342065 DOI: 10.1097/00002030-199712000-00007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To develop a putative immunization cassette using HIV-1 vif accessory gene derived from HIV-1 clinical specimens as a component of a DNA vaccine for HIV-1. METHODS vif genes were cloned from HIV-1-infected patients and the sequence variation present within the patients was analyzed. Prototypic genetic variants were selected and the ability of these clones to induce humoral and cellular immune responses was studied in animals. The selected protective genetic variants were biologically characterized through transcomplementation assays using primary cells infected with a vif-defective HIV-1 proviral clone. RESULTS Analysis of vif variants from different patients revealed that vif is highly conserved with the open reading frame remaining intact in vivo. It was shown that attenuated vif clones from HIV-1-infected subjects can effectively induce both humoral and cellular responses against Vif protein in mice. Evaluation of the cellular responses in vitro using human cellular targets infected with a clinical HIV-1 isolate showed that vif clones could induce cellular responses capable of destroying the virus. CONCLUSIONS The vif variants developed in this study exhibited non-productive phenotypes, yet were capable of inducing specific immune responses against HIV-1. These constructs could be used as part of a DNA vaccine strategy for HIV-1. This vaccine adaptation strategy could be used for the development of immunogens for any pathogen resulting in cross-reactive immunity and attenuated gene pathogenesis.
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MESH Headings
- AIDS Vaccines/genetics
- Amino Acid Sequence
- Animals
- Cloning, Molecular
- DNA, Viral/immunology
- Gene Expression
- Gene Products, vif/genetics
- Gene Products, vif/immunology
- HIV Antibodies/analysis
- HIV Infections/prevention & control
- HIV-1
- Humans
- Mice
- Molecular Sequence Data
- Mutagenesis, Insertional
- Plasmids/metabolism
- Sequence Analysis, DNA
- Tumor Cells, Cultured
- Vaccines, Attenuated/genetics
- Vaccines, DNA/genetics
- vif Gene Products, Human Immunodeficiency Virus
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320
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Waters SB, D'Auria M, Martin SS, Nguyen C, Kozma LM, Luskey KL. The amino terminus of insulin-responsive aminopeptidase causes Glut4 translocation in 3T3-L1 adipocytes. J Biol Chem 1997; 272:23323-7. [PMID: 9287343 DOI: 10.1074/jbc.272.37.23323] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The insulin-responsive aminopeptidase (IRAP) is a constituent of the vesicles that contain the insulin-regulated glucose transporter (Glut4). Like Glut4, IRAP translocates to the cell surface in response to insulin. Microinjection into 3T3-L1 adipocytes of a glutathione S-transferase (GST) fusion protein containing the cytosolic portion of IRAP (GST-IRAP-(1-109)), resulted in translocation of Glut4 to the cell surface. Immunostaining of 3T3-L1 adipocytes for Glut4 showed that the percentage of cells with substantial cell surface Glut4 was 10% in unstimulated cells, 8% following injection of GST, and 27% following injection of GST-IRAP-(1-109). Increased cell surface Glut4 occurred within 5-10 min following injection and was maintained for at least 4 h. A fusion protein containing only 28 amino acids from IRAP (GST-IRAP-(55-82)) was as effective in increasing cell surface Glut4 as stimulation with 100 nM insulin (44% versus 43%, respectively). In contrast to insulin-stimulated Glut4 translocation, the redistribution of Glut4 following injection of GST-IRAP-(55-82) was not blocked by wortmannin or co-injection with a SH2 domain from the regulatory subunit of phosphatidylinositol 3-kinase. These data suggest that the amino terminus of IRAP interacts with a retention/sorting protein that also regulates the distribution of Glut4 in insulin-responsive cells.
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Abstract
Investiture of new microvessels within an injured peripheral nerve trunk may determine the success that the local environment has in promoting axonal sprouting and regeneration. We therefore examined microvessel investment of 24 h-14 d proximal nerve stump preparations in rat sciatic nerves. The stumps, later destined to form neuromas, were created by sciatic nerve transection with resection of distal branches to prevent distal reinnervation. Microvessels were studied in the proximal stump in semithin whole mount sections of nerve and by analysis of India ink perfused microvessel profiles. Quantitative image analysis was made of the luminal profiles of vessels perfused with India ink from unfixed sections of the stumps, contralateral uninjured nerves and sham-exposed but uninjured nerves. Evidence of angiogenesis was observed in stumps 7 d after transection, indicated by a rise in the total numbers of perfused microvessels and in the numbers of 2-6 microns diameter perfused microvessels. There was a shift in the histogram of the percentage of perfused microvessels towards the 2-4 microns range and a reduction in the mean microvessel luminal area in the stumps. By 14 d, new microvessels were larger, indicated by an increase in total luminal area. New microvessels were prominent in the epineurial connective tissue or between layers of perineurial cells of former fascicles. Microvessels probably share a battery of trophic signals with other proliferating cellular elements in the milieu of the injured peripheral nerve trunk.
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322
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Riley LH, Eck JC, Yoshida H, Toth JM, Nguyen C, Lim TH, McGrady LM. Laparoscopic assisted fusion of the lumbosacral spine. A biomechanical and histologic analysis of the open versus laparoscopic technique in an animal model. Spine (Phila Pa 1976) 1997; 22:1407-12. [PMID: 9201846 DOI: 10.1097/00007632-199706150-00021] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
STUDY DESIGN An animal model for laparoscopic lumbosacral fusion. OBJECTIVES To compare the biomechanical and histologic results of open to laparoscopic lumbosacral discectomy and fusion in an animal model. BACKGROUND DATA Early clinical reports of laparoscopic lumbosacral fusions are encouraging, but animal experiments have not been reported. METHODS Ten pigs (50-80 kg) were divided into two groups. Group 1 underwent an open anterior lumbosacral discectomy and fusion at L7-S1 using autologous bone graft and a titanium MOSS (DePuy Motech) cage. Group 2 was identical to Group 1 except that a laparoscopic technique was used. The animals were killed at 3 months, and the lumbosacral spines were harvested for biomechanical and histologic testing. RESULTS Estimated blood loss and average length of operation, respectively, for the two groups were: Group 1, 50 mL, 2 hours 50 minutes; and Group 2, 40 mL, 3 hours 40 minutes. There were no perioperative or postoperative complications in either group. Motion analysis results showed less motion in lateral bending, flexion, and extension than in the intact specimen in both groups. Tensile testing showed that the stiffness was significantly greater in the open group than in the laparoscopic group (P < 0.004). Histologic examination showed a less extensive discectomy and less bone growth in the implant in the laparoscopic group. Inadequate decortication of end-plates occurred in two animals who underwent laparoscopy. CONCLUSIONS Although lumbosacral discectomy and implant insertion can be performed using the laparoscopic technique, the construct may not have the same biomechanical strength as that attained with the open procedure. Laparoscopic-assisted lumbosacral fusion surgery requires additional investigation before it is widely used in clinical situations.
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Uyeda K, Wang XL, Mizuguchi H, Li Y, Nguyen C, Hasemann CA. The active sites of fructose 6-phosphate,2-kinase: fructose-2, 6-bisphosphatase from rat testis. Roles of Asp-128, Thr-52, Thr-130, Asn-73, and Tyr-197. J Biol Chem 1997; 272:7867-72. [PMID: 9065453 DOI: 10.1074/jbc.272.12.7867] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
To investigate the role in catalysis and/or substrate binding of the Walker motif residues of rat testis fructose 6-phosphate, 2-kinase:fructose-2,6-bisphosphatase (Fru 6-P,2-kinase:Fru-2,6-Pase), we have constructed and characterized mutant enzymes of Asp-128, Thr-52, Asn-73, Thr-130, and Tyr-197. Replacement of Asp-128 by Ala, Asn, and Ser resulted in a small decrease in Vmax and a significant increase in Km values for both substrates. These mutants exhibited similar pH activity profiles as that of the wild type enzyme. Mutation of Thr-52 to Ala resulted in an enzyme with an infinitely high Km for both substrates and an 800-fold decreased Vmax. Substitution of Asn-73 with Ala or Asp caused a 100- and 600-fold increase, respectively in KFru 6-P with only a small increase in KATP and small changes in Vmax. Mutation of Thr-130 caused small changes in the kinetic properties. Replacement of Tyr-197 with Ser resulted in an enzyme with severely decreased binding of Fru 6-P with 3-fold decreased Vmax. A fluorescent analog of ATP, 2'(3')-O-(N-methylanthraniloyl)ATP (mant-ATP) served as a substrate with Km = 0.64 microM, and Vmax = 25 milliunits/mg and was a competitive inhibitor with respect to ATP. When mant-ATP bound to the enzyme, fluorescence intensity at 440 nm increased. mant-ATP binding of the wild type and the mutant enzymes were compared using the fluorometric method. The Kd values of the T52A and D128N enzymes were infinitely high and could not be measured, while those of the other mutant enzymes increased slightly. These results provide evidence that those amino acids are involved in substrate binding, and they are consistent with the crystallographic data. The results also suggest that Asp-128 does not serve as a nucleophile in catalysis, and since there are no other potential nucleophiles in the active site, we hypothesize that the Fru 6-P,2-kinase reaction is mediated via a transition state stabilization mechanism.
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Nguyen C, Katner HP. Myeloperoxidase deficiency manifesting as pustular candidal dermatitis. Clin Infect Dis 1997; 24:258-60. [PMID: 9114158 DOI: 10.1093/clinids/24.2.258] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Myeloperoxidase deficiency is the most common neutrophilic lysosomal enzyme deficiency. Case studies indicate that individuals with myeloperoxidase deficiency are not susceptible to serious infection in the absence of coexisting conditions such as diabetes mellitus. We present a case of myeloperoxidase deficiency manifesting as disseminated pustular candidal dermatitis in a nondiabetic male. Ceftriaxone therapy was administered to the patient for 8 days after he received a closed head injury and before the development of fever and pustular dermatitis. Candida albicans was isolated from the skin lesion. His neutrophils demonstrated a qualitative lack of myeloperoxidase. Patients who develop rapidly disseminated fungal dermatitis while they are receiving antimicrobial therapy that is relatively limited in coverage should be evaluated for myeloperoxidase deficiency.
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325
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Rocha D, Carrier A, Naspetti M, Victorero G, Anderson E, Botcherby M, Guénet JL, Nguyen C, Naquet P, Jordan BR. Modulation of mRNA levels in the presence of thymocytes and genome mapping for a set of genes expressed in mouse thymic epithelial cells. Immunogenetics 1997; 46:142-51. [PMID: 9162101 DOI: 10.1007/s002510050253] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Modulation of gene expression in mouse thymic epithelium upon culture in the presence of thymocytes (coculture) was studied by comparison of hybridization signatures on a set of nearly 5000 mouse thymus cDNA clones. Forty-nine differentially expressed clones (usually down-regulated in coculture) were characterized by tag sequencing. Many of them corresponded to entities that had not been described previously in the mouse, and were further characterized by genome mapping. This set of genes appears to be involved in growth regulation and differentiation within the thymus.
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Gaudet T, Aning G, Nguyen C, Piper J. Postpartum/family planning in a school-age obstetric population. Am J Obstet Gynecol 1997. [DOI: 10.1016/s0002-9378(97)80570-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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327
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Rovere P, Trucy J, Zimmermann VS, Granjeaud S, Rocha D, Nguyen C, Ricciardi-Castagnoli P, Jordan BR, Davoust J. Differential mRNA expression in untreated and TNF-alpha elicited murine dendritic cells precursors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1997; 417:467-73. [PMID: 9286405 DOI: 10.1007/978-1-4757-9966-8_77] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have compared the pattern of gene expression in long term cultured precursor dendritic cells (DC), either untreated (immature) or cultured for two days in the presence of recombinant murine (rm)-TNF alpha (mature). The hybridization signature of complex cDNA probes prepared from total RNA extracted from immature and mature DC were analyzed using a mouse thymic cDNA library, gridded on high density filters. For each clone spotted on the filters, we have measured using an imaging plate device the hybridization signals of the complex probe obtained from immature or mature DC. Comparative analysis of these values allowed us to identify differentially expressed gene products. Our goal is to identify a new set of genes induced or repressed during DC maturation elicited by rmTNF alpha treatment.
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Gaudel T, Piper J, Nguyen C, Sayeed A, Gayz C. Are teens at increased risk for poor obstetric outcomes? Am J Obstet Gynecol 1997. [DOI: 10.1016/s0002-9378(97)80485-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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329
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Krown KA, Page MT, Nguyen C, Zechner D, Gutierrez V, Comstock KL, Glembotski CC, Quintana PJ, Sabbadini RA. Tumor necrosis factor alpha-induced apoptosis in cardiac myocytes. Involvement of the sphingolipid signaling cascade in cardiac cell death. J Clin Invest 1996; 98:2854-65. [PMID: 8981934 PMCID: PMC507753 DOI: 10.1172/jci119114] [Citation(s) in RCA: 525] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In the present study, it was shown that physiologically relevant levels of the proinflammatory cytokine TNFalpha induced apoptosis in rat cardiomyocytes in vitro, as quantified by single cell microgel electrophoresis of nuclei ("cardiac comets") as well as by morphological and biochemical criteria. It was also shown that TNFalpha stimulated production of the endogenous second messenger, sphingosine, suggesting sphingolipid involvement in TNFalpha-mediated cardiomyocyte apoptosis. Consistent with this hypothesis, sphingosine strongly induced cardiomyocyte apoptosis. The ability of the appropriate stimulus to drive cardiomyocytes into apoptosis indicated that these cells were primed for apoptosis and were susceptible to clinically relevant apoptotic triggers, such as TNFalpha. These findings suggest that the elevated TNFalpha levels seen in a variety of clinical conditions, including sepsis and ischemic myocardial disorders, may contribute to TNFalpha-induced cardiac cell death. Cardiomyocyte apoptosis is also discussed in terms of its potential beneficial role in limiting the area of cardiac cell involvement as a consequence of myocardial infarction, viral infection, and primary cardiac tumors.
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Bravar A, Adams DL, Akchurin N, Belikov NI, Bonner BE, Bystricky J, Corcoran MD, Cossairt JD, Cranshaw J, Derevschikov AA, En'yo H, Funahashi H, Goto Y, Grachov OA, Grosnick DP, Hill DA, Iijima T, Imai K, Itow Y, Iwatani K, Kharlov YV, Kuroda K, Laghai M, Lehar F, Lopiano D, Luehring FC, Maki T, Makino S, Masaike A, Matulenko YA, Meschanin AP, Michalowicz A, Miller DH, Miyake K, Nagamine T, Nessi-Tedaldi F, Nessi M, Nguyen C, Nurushev SB, Ohashi Y, Onel Y, Patalakha DI, Pauletta G, Penzo A, Rappazzo GF, Read AL, Roberts JB, Rykov VL, Saito N, Salvato G, Schiavon P, Skeens J, Solovyanov VL, Spinka H, Stanek RW, Takashima R, Takeutchi F, Tamura N, Underwood DG, Vasiliev AN, White JL, Yamashita S. Single-Spin Asymmetries in Inclusive Charged Pion Production by Transversely Polarized Antiprotons. PHYSICAL REVIEW LETTERS 1996; 77:2626-2629. [PMID: 10062005 DOI: 10.1103/physrevlett.77.2626] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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331
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Nguyen C, Naghibzadeh B, Black MJ, Rochon L, Shenouda G. Glottic microinvasive carcinoma: is it different from carcinoma in situ? THE JOURNAL OF OTOLARYNGOLOGY 1996; 25:223-6. [PMID: 8863208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the impact of different treatment modalities on the outcome of microinvasive carcinoma. DESIGN Retrospective review of patients presenting between 1976 and 1990. SETTING Fifteen patients with microinvasive carcinoma (MIC) of the glottic larynx treated at McGill University teaching hospitals. METHODS All patients had MIC involving the glottis confirmed pathologically. Nine patients (60%) had right vocal cord involvement, four (27%) had left vocal cord involvement, and two (13%) had involvement of both cords. Five patients (33%) were treated by stripping(S), three patients (20%) by stripping and radiotherapy (S + RT), and six patients (40%) by radiotherapy (RT) alone as the primary treatment. Only one patient underwent hemilaryngectomy. RESULTS With a median follow-up time of 63 months (range 20-208 months), the 15-year actuarial survival rate is 100% for all patients. CONCLUSIONS Surgery alone, RT alone, or S + RT is equally effective in treating MIC of the glottic larynx; however, single-modality therapy is preferred. The choice of treatment modality should be individualized for each patient.
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Thomas M, Blank HR, Wong KC, Nguyen C, Kroemer H, Hu EL. Flux-periodic resistance oscillations in arrays of superconducting weak links based on InAs-AlSb quantum wells with Nb electrodes. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:R2311-R2314. [PMID: 9986165 DOI: 10.1103/physrevb.54.r2311] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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333
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Hook VY, Schiller MR, Nguyen C, Yasothornsrikul S. Production of radiolabeled neuropeptide precursors by in vitro transcription and translation. PEPTIDE RESEARCH 1996; 9:183-187. [PMID: 8914165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Bioactive peptide hormones and neurotransmitters are required for neuroendocrine regulation of cellular functions. Importantly, proteolytic processing of inactive neuropeptide precursors is required to generate physiologically active peptide hormones and neurotransmitters. Studies of the processing enzymes require authentic neuropeptide precursors as substrates, rather than peptide substrates. This study demonstrates an efficient method to general 35S-precursors from cloned cDNAs by in vitro transcription and translation. In vitro transcription of neuropeptide cDNAs with SP6 RNA polymerase generates large amounts (micrograms) of corresponding RNAs. Subsequent in vitro translation of RNAs with wheat germ extract and 35S-methionine generates large quantities of 35S-precursors (10-25 million cpm 35S-precursor protein per reaction) with high specific radioactivity. The radiolabeled precursor substrates offer a reliable, sensitive and accurate method for detecting the proteolytic activity. Importantly, specific detection of the primary proenkephalin processing activity in chromaffin granules by 35S-enkephalin precursor as substrate, but not by peptide methylcoumarinamide (MCA) substrates, illustrates the significance of using full-length precursor to detect appropriate processing enzymes. This study demonstrates that efficient production of radiolabeled neuropeptide precursors by in vitro transcription and translation will be useful for in vitro assays of relevant processing proteases.
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334
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Atuegbu A, Maclean D, Nguyen C, Gordon EM, Jacobs JW. Combinatorial modification of natural products: preparation of unencoded and encoded libraries of Rauwolfia alkaloids. Bioorg Med Chem 1996; 4:1097-106. [PMID: 8831981 DOI: 10.1016/0968-0896(96)00093-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report the preparation of combinatorial libraries which consist of derivatives of the stereoisomeric alkaloids yohimbine and rauwolscine-members of the Rauwolfia genus. The chemistry was performed on solid support using the divide-and-pool method, and involved the derivatization of the E-ring carboxylates and hydroxyls of these alkaloids with 36 amino acids and 22 carboxylic acids, respectively, to afford 792 bifunctionalized derivatives. The rauwolscine library was prepared using an encoding strategy in which the identity of each incorporated amino acid was recorded by cosynthesizing chemically inert tags prior to the pooling step. The general strategy for library synthesis exploits existing functionality present on the natural products, and should be applicable to other families of secondary metabolites.
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Abstract
BACKGROUND The management of glottic carcinoma in situ (CIS) is controversial, with vocal cord stripping (S) generally accepted as the standard treatment, and radiotherapy (RT) as an alternative. We present our experience with 34 patients treated by either stripping or RT. METHODS ++Between 1974 and 1990, 34 patients with CIS of the glottic larynx larynx were treated at McGill University teaching hospitals. The median age at diagnosis was 67 years, with a male:female ratio of 6:1. All patients had CIS involving the glottis and the pathology was reviewed on all patients. Twenty-one patients were treated by S and 13 patients by RT as the primary treatment. RESULTS With a median follow-up of 96 months (25-209 months), the 15-year actuarial survival rate is 95% for all patients, with 100% and 87% survival rates for S and RT groups, respectively (p = 0.25). One patient in the RT group developed a subglottic invasive squamous cell carcinoma. On the other hand, 11 patients in the S group developed recurrence and were treated by repeat S (6 patients) or RT (5 patients), with a salvage rate of 100%. CONCLUSION Although most patients with CIS of the glottis are traditionally treated with vocal cord S, RT is effective in terms of freedom from recurrence; it is an attractive option and should be considered in patients with lesions recurring after stripping as well as in those whose follow-up presents a problem.
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Adams DL, Akchurin N, Belikov NI, Bravar A, Bystricky J, Corcoran MD, Cossairt JD, Cranshaw J, Derevschikov AA, En'yo H, Funahashi H, Goto Y, Grachov OA, Grosnick DP, Hill DA, Iijima T, Imai K, Itow Y, Iwatani K, Krueger KW, Kuroda K, Lehar F, Lopiano D, Luehring FC, Maki T, Makino S, Masaike A, Matulenko YA, Meschanin AP, Michalowicz A, Miller DH, Miyake K, Nagamine T, Nessi-Tedaldi F, Nessi M, Nguyen C, Nurushev SB, Ohashi Y, Onel Y, Patalakha DI, Pauletta G, Penzo A, Read AL, Roberts JB, Rykov VL, Saito N, Salvato G, Schiavon P, Shima T, Skeens J, Solovyanov VL, Spinka H, Stanek RW, Takashima R, Takeutchi F, Tamura N, Tanaka N, Underwood DG, Vasiliev AN, White JL, Yamashita S, Yokosawa A. Single-spin asymmetries and invariant cross sections of the high transverse-momentum inclusive pi 0 production in 200 GeV/c pp and p-barp interactions. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1996; 53:4747-4755. [PMID: 10020471 DOI: 10.1103/physrevd.53.4747] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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337
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Bernard K, Auphan N, Granjeaud S, Victorero G, Schmitt-Verhulst AM, Jordan BR, Nguyen C. Multiplex messenger assay: simultaneous, quantitative measurement of expression of many genes in the context of T cell activation. Nucleic Acids Res 1996; 24:1435-42. [PMID: 8628675 PMCID: PMC145825 DOI: 10.1093/nar/24.8.1435] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The hybridization signature approach, using colony filters and labeled complex probes, can provide high throughput measurement of gene activity. We describe here the implementation of this method to follow the expression levels of 47 genes in resting and activated T cells, as well as in epithelial cells. Using 4-fold spotting of colonies, imaging plate detection and various correction and normalization procedures, the technique is sensitive enough to quantify expression levels for sequences present at 0.005% abundance in the probe. Comparison with Northern blotting shows good consistency between the two methods. Upon activation of a T cell clone by an anti-CD3 antibody variations ranging from 2- to 20-fold are measured, some of which had not been reported previously. This 'multiplex messenger assay' method, performed using available commercial apparatus, can be used in many cases where simultaneous assessment of mRNA levels for many genes is of interest.
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Granjeaud S, Nguyen C, Rocha D, Luton R, Jordan BR. From hybridization image to numerical values: a practical, high throughput quantification system for high density filter hybridizations. GENETIC ANALYSIS : BIOMOLECULAR ENGINEERING 1996; 12:151-62. [PMID: 8673741 DOI: 10.1016/1050-3862(95)00128-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Hybridization to sets of bacterial colonies or PCR products arrayed on high density filters is used in a number of experimental schemes. In many cases it is desirable to collect quantitative information ('hybridization signatures') rather than indications on 'positive' and 'negative' colonies. We present a practical system, based on an imaging plate analyser and a customized version of commercial software, that makes such quantification feasible, and define its performance in terms of reproducibility and linearity. The system is far superior to methods based on autoradiography and should be useful in many projects that involve the increasingly popular high density filter format.
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Nguyen C, Lander P, Begin LR, Jarzem P, Grad R. AIDS-related Kaposi sarcoma involving the tarsal bones. Skeletal Radiol 1996; 25:100-2. [PMID: 8717133 DOI: 10.1007/s002560050044] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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340
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Nguyen C, Misery L, Tigaud JD, Petiot A, Fiere D, Faure M, Claudy A. [Psoriasis induced by interferon-alpha. Apropos of a case]. ANNALES DE MEDECINE INTERNE 1996; 147:519-21. [PMID: 9092366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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341
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Nguyen C, Souhami L, Roman TN, Clark BG. High-dose-rate brachytherapy as the primary treatment of medically inoperable stage I-II endometrial carcinoma. Gynecol Oncol 1995; 59:370-5. [PMID: 8522257 DOI: 10.1006/gyno.1995.9960] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Between 1984 and 1992, 27 patients with clinical stage I-II histologically proven adenocarcinoma of the endometrium who had significant medical risks precluding surgery underwent radiotherapy (RT) as the primary treatment. The median age at diagnosis was 74 years. There were 20 patients (74%) with stage I and 7 patients (26%) with stage II disease. Patients were treated with high-dose-rate brachytherapy (HDRB) alone (19/27) or with a combination of external-beam RT and HDRB (2 stage I; 6 stage II). HDRB was delivered using a cobalt-60 HDR remote afterloading unit, with a median dose of 2000 cGy to point A, in two to three fractions given once a week. All HDRB treatments were performed under spinal anesthesia on an outpatient basis. External-beam irradiation to the pelvis was given using 4- to 6-MV photons and a median dose of 4200 cGy was delivered. In all patients, vaginal bleeding was controlled within a few days after completion of RT. With a median follow-up of 47 months, the 8-year disease-specific survival rate was 76%. Patients with stage I had an 8-year survival rate superior to that of patients with stage II (95% vs 21%, P < 0.001). No complications were experienced during HDRB. Late serious complications were seen in 3 patients (11%). Based on this retrospective review, primary RT with HDRB appears to be an effective and safe treatment for those patients with medically inoperable clinical stage I endometrial carcinoma. Because HDRB is given on an outpatient basis, it is an attractive option for these patients. However, in stage II disease the results of treatment are poor and RT alone should be considered only when the surgical risks are too high.
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Krown KA, Yasui K, Brooker MJ, Dubin AE, Nguyen C, Harris GL, McDonough PM, Glembotski CC, Palade PT, Sabbadini RA. TNF alpha receptor expression in rat cardiac myocytes: TNF alpha inhibition of L-type Ca2+ current and Ca2+ transients. FEBS Lett 1995; 376:24-30. [PMID: 8521959 DOI: 10.1016/0014-5793(95)01238-5] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Tumor necrosis factor-alpha (TNF alpha) is a potentially powerful anti-neoplastic agent; however, its therapeutic usefulness is limited by its cardiotoxic and negative inotropic effects. Accordingly, studies were undertaken to gain a better understanding of the mechanisms of TNF alpha-mediated cardiodepression. Single cell RT-PCR, [125I]TNF alpha ligand binding and Western immunoblotting experiments demonstrated that rat cardiac cells predominantly express type I TNF alpha receptors (TNFRI or p60). TNF alpha inhibited cardiac L-type Ca2+ channel current (ICa) and contractile Ca2+ transients. Thus, it is possible that the negative inotropic effects of TNF alpha are the result of TNFRI-mediated blockade of cardiac excitation-contraction coupling.
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Panico WH, Cavuto NJ, Kallimanis G, Nguyen C, Armstrong DM, Benjamin SB, Gillis RA, Travagli RA. Functional evidence for the presence of nitric oxide synthase in the dorsal motor nucleus of the vagus. Gastroenterology 1995; 109:1484-91. [PMID: 7557129 DOI: 10.1016/0016-5085(95)90634-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND & AIMS Histochemical studies indicate that reduced nicotinamide adenine dinucleotide phosphate diaphorase, the nitric oxide synthase-related enzyme, is present in the dorsal motor nucleus of the vagus of the cat. We have previously shown in vitro that NO synthase is present in this nucleus in the rat and that the excitatory effect of N-methyl-D-aspartate on these neurons is in part caused by NO formation. The aim of this study was to obtain functional evidence for the presence of NO synthase in the cat dorsal motor nucleus of the vagus. METHODS L-Glutamate, L-arginine, D-arginine, the NO donor S-nitroso-N-acetyl-penicillamine, and the NO synthase inhibitor NG-nitro-L-arginine-methyl ester were unilaterally microinjected into the rostral dorsal motor nucleus of anesthetized cats, and antral and pyloric motility were monitored using extraluminal force transducers. RESULTS Microinjection of L-arginine increased gastric motility, whereas D-arginine had no effect. Vagotomy eliminated the L-arginine-induced increases. Microinjection of S-nitroso-N-acetyl-penicillamine increased antral motility. NG-Nitro-L-arginine-methyl ester prevented L-arginine from exerting an effect on gastric motility. CONCLUSIONS Motility increases obtained after microinjection of L-arginine into the dorsal motor nucleus and prevention of these motility increases with microinjection of a NO synthase inhibitor provide functional evidence for the presence of NO synthase in the dorsal motor nucleus of the vagus in the cat.
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Bravar A, Adams DL, Akchurin N, Belikov NI, Bonner BE, Bystricky J, Corcoran MD, Cossairt JD, Cranshaw J, Derevschikov AA, En'yo H, Funahashi H, Goto Y, Grachov OA, Grosnick DP, Hill DA, Iijima T, Imai K, Itow Y, Iwatani K, Krueger K, Kuroda K, Laghai M, Langland JL, Lehar F, Lopiano D, Luehring FC, Maki T, Makino S, Masaike A, Matulenko YA, Meschanin AP, Michalowicz A, Miller DH, Miyake K, Nagamine T, Nessi-Tedaldi F, Nessi M, Nguyen C, Nurushev SB, Ohashi Y, Onel Y, Patalakha DI, Pauletta G, Penzo A, Rappazzo GF, Read AL, Roberts JB, Rykov VL, Saito N, Salvato G, Schiavon P, Skeens J, Solovyanov VL, Spinka H, Stanek RW, Takashima R, Takeutchi F, Underwood DG, Vasiliev AN, White JL, Yamashita S. Analyzing power measurement in inclusive Lambda 0 production with a 200 GeV/c polarized proton beam. PHYSICAL REVIEW LETTERS 1995; 75:3073-3077. [PMID: 10059488 DOI: 10.1103/physrevlett.75.3073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Nguyen C, Rocha D, Granjeaud S, Baldit M, Bernard K, Naquet P, Jordan BR. Differential gene expression in the murine thymus assayed by quantitative hybridization of arrayed cDNA clones. Genomics 1995; 29:207-16. [PMID: 8530073 DOI: 10.1006/geno.1995.1233] [Citation(s) in RCA: 143] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
High-throughput measurement of hybridization signatures obtained using complex probes prepared from poly(A)+ RNA and high-density cDNA colony filters is described. The performance of the system, elimination of artifacts, and verification of the validity of the data are discussed. cDNAs corresponding to sequences present at levels of approximately 0.01% in the complex probe can be detected. Good correlation is observed between expression profiles determined by this method and by Northern blotting. The method is applied to a preliminary investigation of differential expression in three cell types present in the murine thymus.
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346
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An HS, Andreshak TG, Nguyen C, Williams A, Daniels D. Can we distinguish between benign versus malignant compression fractures of the spine by magnetic resonance imaging? Spine (Phila Pa 1976) 1995; 20:1776-82. [PMID: 7502133 DOI: 10.1097/00007632-199508150-00005] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN The authors investigate the usefulness of magnetic resonance imaging in differentiating benign versus malignant compression fractures by reviewing patients and a fracture model in a canine model. OBJECTIVES To determine the sensitivity and specificity of magnetic resonance imaging in differentiating benign versus malignant compression fractures of the spine and to obtain distinguishing features in magnetic resonance imaging. SUMMARY OF BACKGROUND DATA The differentiation between benign and abnormal compression fractures of the thoracolumbar spine has important implications regarding patient treatment and prognosis. Plain radiographs, bone scans, and computed tomography are not accurate imaging modalities for this purpose. METHODS Magnetic resonance imaging scans of 22 patients with confirmed lesions of the thoracolumbar spine were studied. There were 11 malignant and 11 benign lesions. Two experienced neuroradiologists blindly reviewed the magnetic resonance imaging scans and determined benign or malignant lesions. A canine study was performed to simulate a compression fracture model with a vertebral osteotomy in two dogs, and serial contrast-enhanced magnetic resonance imaging scans were performed 15, 30, 60 and 90 days after surgery. RESULTS The correct interpretation between two neuroradiologists was 77% and 95%. The combined sensitivity rate was 88.5%, and the specificity rate was 89.5%. Magnetic resonance imaging reliably distinguished benign versus malignant lesions based on the anatomic distribution and intensity of signal changes of bone and adjacent tissues, contrast enhancement characteristics, and changes over time. Only one malignant lesion was misinterpreted by both neuroradiologists as benign, whereas there was one additional missed malignant lesion and three misinterpreted benign lesions by one radiologist. In the canine study, signal changes and enhancement were found 60 days after surgery, but no signal changes or enhancement were noted on the scan 90 days after surgery. CONCLUSIONS Magnetic resonance imaging scans can detect malignant vertebral lesions early, but acute healing compression fractures may mimic the findings of metastatic lesions. The use of contrast-enhanced magnetic resonance imaging scans and serial magnetic resonance imagings are helpful for additional differentiation between benign and malignant compression fractures. In addition to magnetic resonance imaging scans, other diagnostic tests and clinical findings should be correlated before biopsy or surgery of the suspected lesion.
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347
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Morris GE, Nguyen C. Specificity and VH sequence of two monoclonal antibodies against the N-terminus of dystrophin. Biochem J 1995; 309 ( Pt 1):355-9. [PMID: 7619079 PMCID: PMC1135841 DOI: 10.1042/bj3090355] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have used a random library of 15-mer peptides expressed on phage to show that two monoclonal antibodies (mAbs) require only the first three amino acids of dystrophin (Leu-Trp-Trp) for binding. Since the mAbs recognize dystrophin in frozen muscle sections, the results suggest that this hydrophobic N-terminus of dystrophin is accessible to antibody in situ. Quantitative binding studies suggested minor differences in specificity between the two mAbs, so the Ig heavy-chain variable region (VH) sequences of the two hybridomas were determined by RT-PCR and cDNA sequencing. After elimination of PCR errors, the two cDNA sequences were found to be identical except for five somatic mutations which resulted in three amino acid changes in the second hypervariable region (CDR2). The results suggest that the two hybridomas originated from the same lymphocyte clone in a germinal centre of the spleen, but underwent different point mutations and subtype switches during clonal expansion to form blast cells.
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Castle S, Nguyen C, Joaquin A, Coyne B, Heuston C, Chan A, Percy L, Ohmen J. Megestrol acetate suspension therapy in the treatment of geriatric anorexia/cachexia in nursing home patients. J Am Geriatr Soc 1995; 43:835-6. [PMID: 7602046 DOI: 10.1111/j.1532-5415.1995.tb07065.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Abe Y, Minami Y, Li Y, Nguyen C, Uyeda K. Expression of bovine heart fructose 6-phosphate,2-kinase:fructose 2,6-bisphosphatase and determination of the role of the carboxyl terminus by mutagenesis. Biochemistry 1995; 34:2553-9. [PMID: 7873535 DOI: 10.1021/bi00008a020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Bovine heart fructose 6-P,2-kinase:fructose 2,6-bisphosphatase was expressed in Escherichia coli. In order to determine the role of the carboxyl-terminal peptide, 49 and 78 amino acids from the C-terminus were deleted using oligonucleotide-directed mutagenesis. The expressed wild-type and mutant enzymes were purified to homogeneity, and the steady-state kinetics of the mutant enzymes were compared to those of the wild-type enzyme. Deletion of 49 residues (Del 49) resulted in a 35% decrease in KmFru6P, a 36% increase in Vmax, and a 2-fold increase in Kcat/Km of the kinase. There was no change in the kinetic properties of the phosphatase activity. Deletion of 78 residues (Del 78) resulted in a 4.5-fold decrease in KmFru6P, a 2.5-fold increase in Vmax, a 12-fold increase in kcat/Km of the kinase, and a 3-fold increase in kcat/Km of the phosphatase. Phosphorylation of the wild-type and Del 49 enzymes resulted in decreased KmFru6P and activation of the kinase without affecting the phosphatase activity. Thermal inactivation rates of the wild-type and Del 49 enzymes were similar, but the rate of Del 78 was more rapid. The phosphorylated wild-type and Del 49 enzymes were more sensitive to thermal inactivation than the dephospho forms. Urea inactivation of the kinase and phosphatase of wild-type and Del 49 were similar, but Del 78 was more sensitive to urea. All phosphorylated enzymes were more susceptible to urea inactivation.(ABSTRACT TRUNCATED AT 250 WORDS)
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Nguyen C, Haughton VM, Ho KC, An HS, Myklebust JB, Hasegawa T, Xu R, Harb JM. Contrast enhancement in spinal nerve roots: an experimental study. AJNR Am J Neuroradiol 1995; 16:265-8. [PMID: 7726071 PMCID: PMC8338345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
PURPOSE To examine histopathologically the endothelium of contrast-enhancing spinal nerve roots. METHODS In five adult baboons, chronic compression of the left S-1 spinal nerve root sufficient to produce a change in the evoked potential was produced by means of a suture tied around the nerve. The animals were studied with MR at 8 and 16 days after nerve compression and then killed for histopathologic and electron microscopic studies. Histopathologic changes in the nerve roots demonstrating contrast enhancement were described. RESULTS In all compressed spinal nerves, contrast enhancement was observed. Histopathologically, wallerian degeneration of the root and inflammation and disruption of the endothelium of capillaries in the spinal nerve were evident. CONCLUSIONS Degenerative changes in the nerve root and the capillary endothelium of a lumbar spinal nerve are associated with contrast enhancement.
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