526
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Anderson LC, Yang SC, Xie H, Lamont RJ. The effects of streptozotocin diabetes on salivary-mediated bacterial aggregation and adherence. Arch Oral Biol 1994; 39:261-9. [PMID: 8024489 DOI: 10.1016/0003-9969(94)90115-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Diabetic rats are known to have an increased susceptibility to dental caries and major alterations in parotid salivary composition. Salivary proteins play an important part in oral health maintenance; thus specific changes in salivary protein composition in diabetic animals might alter the ecological balance in favour of cariogenic bacteria, and toward the initiation and progression of the disease process. The ability of whole, parotid and submandibular salivas from control and streptozotocin-diabetic rats to mediate the aggregation and adherence to hydroxyapatite of mutans streptococci was examined. Salivary-mediated bacterial aggregating activity was significantly reduced in whole and parotid salivas from diabetic rats, but bacterial adherence to hydroxyapatite was unaffected. The aggregating and adherence activities of rat whole saliva were derived mainly from parotid saliva, which contains predominantly low molecular-weight proteins and glycoproteins (< 200 kDa), but rat parotid saliva was capable of interacting with the bacterial receptor for the high molecular-weight aggregating factor in human saliva. SDS-PAGE of parotid saliva revealed that a number of proteins, including the basic and acid proline-rich proteins, were altered in the salivas of diabetic animals. After incubation with either Streptococcus mutans or hydroxyapatite several protein bands were depleted, and thus a variety of proteins and glycoproteins may be responsible for the adherence and aggregating activity of rat parotid saliva.
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527
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Xie H, Triggle CR. Endothelium-independent relaxations to acetylcholine and A23187 in the human umbilical artery. J Vasc Res 1994; 31:92-105. [PMID: 8117864 DOI: 10.1159/000159035] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The effects of acetylcholine (ACh) and A23187 on ring preparations from the human umbilical artery (HUA) were investigated and compared with the rat aorta (RA). The results from the HUA demonstrate that: (1) At both high (pO2 > 600 mm Hg) and low O2 tension (pO2 < 55 mm Hg), ACh and A23187 relaxed precontracted rings in a concentration-dependent and endothelium-independent manner. Changes in pO2 did not influence the responses of the HUA to either relaxant. (2) Relaxation responses of the HUA to either ACh or A23187 were insensitive to methylene blue (50 microM), L-nitro-arginine methyl ester (100 microM), indomethacin (10 microM) and nordihydroguaiaretic acid (50 microM). Relaxations initiated by ACh were also atropine-resistant. (3) Meclofenamic acid (3 microM) suppressed the relaxations to A23187, but not ACh. (4) Regardless of pO2 superoxide dismutase (100 U/ml) potentiated the relaxant effects of ACh, whereas mannitol (60 mM) enhanced ACh-initiated relaxations at high but not low pO2. (5) Ouabain (30 nM), high potassium (HK+, 60 mM) and tetraethylammonium (20 mM) inhibited responses to ACh. (6) Na(+)-free physiological saline solution inhibited both relaxations and oscillations initiated by either ACh or A23187. (7) Both nitroglycerin and exogenous nitric oxide (NO) fully, and 8-bromoguanosine 3',5'-cyclic monophosphate partially, relaxed the HUA, and LY83583 (10 microM) reversed such relaxations. (8) In the RA, relaxation responses to ACh and A23187 were endothelium-dependent and sensitivity was reduced under high versus low pO2 conditions. We conclude that in the HUA, unlike in the RA, ACh and A23187 mediate their responses via an endothelium- and NO-independent process(es), perhaps involving the release of a muscle-derived relaxing factor. ACh-initiated relaxations are mediated by activation of Na+,K(+)-ATPase, and subsequent hyperpolarization via K+ efflux, whereas A23187-mediated relaxations result from the synthesis of an indomethacin-resistant cyclooxygenase product.
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528
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Troyer DL, Xie H, Goad DW, Skinner DZ. Use of a new technique to map the porcine alpha interferon gene to chromosome 1. Mamm Genome 1994; 5:112-4. [PMID: 8180470 DOI: 10.1007/bf00292338] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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529
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Wang AJ, Hu MX, Xie H, Fan YZ, Sun CL, Ru LQ, Lin CY. [Improvement of memory function of fornix-fimbria transected rats by transplantation of the superior cervical ganglion into hippocampus]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1994; 46:90-4. [PMID: 8085175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Memory impairments of passive avoidance response were observed in 38 Wistar rats with bilateral fornix-fimbria transection. After fornix-fimbria lesions the degree of performance decreased from 65.3% to 13.6% (P < 0.01). Autotransplantation of superior cervical ganglion (SCG) into bilateral dorsal hippocampi improved memory function to a considerable extent. In the end of the behavioral experiments, implanted rats were sacrificed for histofluorescence study of grafts and measurement of norepinephrine (NA) content in the hippocampus. These experiments showed that the hippocampal NA content in implanted rats was considerably higher than that in untransplanted fornix-fimbria transected rats and consequently suggested that improvement of memory function was to some extent due to supplement of monoamine transmitter by the transplanted SCG.
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530
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Xie H, Clarke S. Protein phosphatase 2A is reversibly modified by methyl esterification at its C-terminal leucine residue in bovine brain. J Biol Chem 1994; 269:1981-4. [PMID: 8294450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We have recently described a novel protein carboxyl methylation system that results in the reversible modification of a 36-kDa polypeptide component of a 178-kDa protein in the cytosol of a variety of eucaryotic cells. This reaction, catalyzed by a cytosolic 40-kDa methyl-transferase, results in the methyl esterification of the alpha-carboxyl group of the C-terminal leucine residue. We have now purified the major methylated 36-kDa polypeptide from bovine brain. N-terminal sequence analysis of a tryptic fragment of this polypeptide revealed identity to the catalytic subunit of protein phosphatase 2A. This enzyme exists in the cell predominantly as a trimeric 151-kDa native species containing the 36-kDa catalytic polypeptide that terminates in a leucine residue. We then fractionated bovine brain cytosolic extracts to separate the major phosphatase isoforms 2A1 and 2A2 and found that both could be methylated by a partially purified preparation of the methyltransferase. A synthetic C-terminal octapeptide based on the sequence of the 36-kDa catalytic subunit is neither a substrate nor an inhibitor of this methyltransferase, suggesting that this enzyme recognizes aspects of the tertiary and/or quaternary structure of the native phosphatase. Because this modification reaction is readily reversible in extracts, it may represent a novel strategy of the cell to modulate the function of this protein phosphatase.
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531
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Troyer DL, Goad DW, Xie H, Rohrer GA, Alexander LJ, Beattie CW. Use of direct in situ single-copy (DISC) PCR to physically map five porcine microsatellites. CYTOGENETICS AND CELL GENETICS 1994; 67:199-204. [PMID: 8062597 DOI: 10.1159/000133822] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Direct in situ single-copy polymerase chain reaction (DISC-PCR) was used to assign and orient a linkage group to pig chromosome 1. Five microsatellites were analyzed, and all five were successfully localized using this procedure. Physical data were used to orient the linkage group with respect to the centromere and estimate the amount of coverage of chromosome 1. There was excellent concordance between the physical and linkage maps. The linear order of the microsatellites was identical, and relative distances were similar. All markers were located on the long arm of chromosome 1. Coverage was estimated at about 32%. Thus, DISC-PCR rapidly and easily assigned and ordered microsatellite markers for which large genomic clones do not exist.
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532
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Xie H, Clarke S. Protein phosphatase 2A is reversibly modified by methyl esterification at its C-terminal leucine residue in bovine brain. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)42124-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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533
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Xie H, Bittar EE. Deregulation by zinc of the sodium efflux in barnacle muscle fibers. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1153:219-24. [PMID: 8274491 DOI: 10.1016/0005-2736(93)90408-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Single muscle fibers from the barnacle Balanus nubilus were employed to study the behavior of the resting Na+ efflux toward external and internal application of zinc (Zn2+). This involved both unpoisoned and ouabain-poisoned fibers. The results obtained are as follows: (i) External application of Zn2+, e.g., 2 mM (a maximal dosage) in 10 mM Hepes-ASW (pH 7.3) causes a fall in the resting Na+ efflux which exceeds that caused by 10(-4) M ouabain in companion controls. (ii) The buffer of choice is found to be Hepes, rather than HCO3- or imidazole. (iii) The observed fall in the resting Na+ efflux caused by external application of Zn2+ is concentration-dependent, the IC50 being 10 microM. (iv) The inhibitory effect of Zn2+ is partially reversible; occasionally, however, reversibility is not seen. (v) The Zn(2+)-insensitive component of the Na+ efflux is reduced by 10(-4) M ouabain. (vi) The ouabain-insensitive component of the Na+ efflux is reduced by external application of Zn2+. This response is concentration-dependent. (vii) Preinjection of EGTA reduces the sensitivity of the Na+ efflux to external application of Zn2+. This is true of both unpoisoned and ouabain-poisoned fibers. (viii) (a) The resting Na+ efflux is reduced by injecting Zn2+. Ouabain application reduces the remaining Na+ efflux. (b) Injection of Zn2+ reduces the ouabain-insensitive component of the Na+ efflux. (c) External application of Zn2+ following the injection of Zn2+ reduces the remaining Na+ efflux. Ouabain is ineffective when applied after both maneuvers. (d) Injection of Zn2+ after its external application is without effect. Subsequent application of ouabain is also without effect. (e) Injection or external application of Zn2+ reduces the ouabain-insensitive Na+ efflux. Whereas in the former case subsequent external application of Zn2+ reduces the remaining Na+ efflux, in the latter case Zn2+ injection after external application of Zn2+ is ineffective. Collectively, these results provide evidence in support of the hypothesis that Zn2+ is a potent inhibitor of the ouabain-sensitive and ouabain-insensitive components of the Na+ efflux, and that the inhibitory effect is partly due to the entry of Zn2+ into the myoplasm. They also raise the possibility that the inhibitory effect caused by Zn2+ injection may be the result of Zn2+ leakage from the fiber interior.
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534
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Xie H, Ender C, Gerl J, Härtlein T, Köck F, Kröll T, Reiter P, Schwalm D, Thirolf P, Vetter K, Wieswesser A, Wollersheim HJ. Coulomb excitation of the K pi =8(-) isomer in 178Hf. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1993; 48:2517-2519. [PMID: 9969110 DOI: 10.1103/physrevc.48.2517] [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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535
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Kempa K, Bakshi P, Xie H. Current-driven plasma instabilities in modulated lower-dimensional semiconductor systems. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:9158-9161. [PMID: 10007145 DOI: 10.1103/physrevb.48.9158] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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536
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Xie H, Chiles TC, Rothstein TL. Induction of CREB activity via the surface Ig receptor of B cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1993; 151:880-9. [PMID: 8393039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The regulation and function of CREB was examined in B cells to begin to elucidate the role of cAMP-derived signals in B cell activation. CRE-binding activity detected by the electrophoretic mobility shift assay was found to be constitutively expressed in nuclear extracts of primary murine splenic B cells and was unchanged in nuclear extracts obtained from B cells stimulated in a variety of ways. This activity was shown to be specific by competition analysis and to represent CREB or a closely related molecule on the basis of a "supershift" in the mobility of the nucleoprotein complex induced by anti-CREB antiserum. The function of B cell CREB was assessed by transient transfection of the murine B lymphoma cell line, BAL-17, with a CRE-dependent chloramphenicol acetyl-transferase (CAT) construct that contains a portion of the somatostatin promoter. Cross-linking of the surface Ig receptors of transfected BAL-17 B cells produced a threefold induction of CAT activity. Forskolin, which markedly induced CAT expression in PC12 cells transfected with the CRE-dependent construct, failed to stimulate CAT activity in transfected BAL-17 B cells despite an increase in cAMP. However, anti-Ig was found to act in synergy with forskolin to produce enhanced CAT activity. A phosphoprotein of appropriate molecular size for CREB was immunoprecipitated from anti-Ig plus forskolin treated BAL-17 B cells. These results suggest that CREB is present in primary B cells and that CRE-dependent gene expression is regulated by surface Ig either alone or in synergy with cAMP; the latter implies cross-talk between intracellular signaling pathways acting at the level of CREB.
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537
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Xie H, Chiles TC, Rothstein TL. Induction of CREB activity via the surface Ig receptor of B cells. THE JOURNAL OF IMMUNOLOGY 1993. [DOI: 10.4049/jimmunol.151.2.880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
The regulation and function of CREB was examined in B cells to begin to elucidate the role of cAMP-derived signals in B cell activation. CRE-binding activity detected by the electrophoretic mobility shift assay was found to be constitutively expressed in nuclear extracts of primary murine splenic B cells and was unchanged in nuclear extracts obtained from B cells stimulated in a variety of ways. This activity was shown to be specific by competition analysis and to represent CREB or a closely related molecule on the basis of a "supershift" in the mobility of the nucleoprotein complex induced by anti-CREB antiserum. The function of B cell CREB was assessed by transient transfection of the murine B lymphoma cell line, BAL-17, with a CRE-dependent chloramphenicol acetyl-transferase (CAT) construct that contains a portion of the somatostatin promoter. Cross-linking of the surface Ig receptors of transfected BAL-17 B cells produced a threefold induction of CAT activity. Forskolin, which markedly induced CAT expression in PC12 cells transfected with the CRE-dependent construct, failed to stimulate CAT activity in transfected BAL-17 B cells despite an increase in cAMP. However, anti-Ig was found to act in synergy with forskolin to produce enhanced CAT activity. A phosphoprotein of appropriate molecular size for CREB was immunoprecipitated from anti-Ig plus forskolin treated BAL-17 B cells. These results suggest that CREB is present in primary B cells and that CRE-dependent gene expression is regulated by surface Ig either alone or in synergy with cAMP; the latter implies cross-talk between intracellular signaling pathways acting at the level of CREB.
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538
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Xie H, Clarke S. Methyl esterification of C-terminal leucine residues in cytosolic 36-kDa polypeptides of bovine brain. A novel eucaryotic protein carboxyl methylation reaction. J Biol Chem 1993; 268:13364-71. [PMID: 8514774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Incubation of cytosolic extracts of bovine brain with S-adenosyl[methyl-3H]methionine results in the predominant [3H]methyl esterification of a 36-kDa polypeptide. This reaction appears to be distinct from any of the three known types of protein carboxyl methylation reactions previously established. We show here that the methylated 36-kDa polypeptide is a component of a cytosolic protein with a native molecular mass estimated at 178 kDa by gel filtration chromatography. The methyl group is not stable on the protein and is lost as [3H]methanol with a half-life of about 180 min at pH 7.0, 37 degrees C. The methyltransferase responsible for this reaction is a cytosolic protein with a native molecular mass of about 40 kDa that is readily separated from the well described protein-L-isoaspartate (D-aspartate) O-methyltransferase (EC 2.1.1.77). The methyl ester linkage is cleaved by carboxypeptidase Y, suggesting that the 36-kDa polypeptide is methylated on its C-terminal carboxyl group. Extensive digestion of gel-purified 3H-methylated 36-kDa polypeptide with trypsin and leucine aminopeptidase results in a radioactive product that co-chromatographs with authentic L-leucine methyl ester in reverse phase high performance liquid chromatography (HPLC), thin layer chromatography, thin layer electrophoresis, and high resolution-sulfonated polystyrene cation-exchange chromatography. Additionally, the o-phthalaldehyde/beta-mercaptoethanol-derived isoindole derivative of the 3H digestion product co-migrates on HPLC with the corresponding isoindole for L-leucine methyl ester. We demonstrate that a similar methylation system is present in yeast Saccharomyces cerevisiae but not in the bacterium Escherichia coli. These results provide evidence for a new type of reversible posttranslational modification reaction that may function to modulate the activities of its methyl-accepting substrates.
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539
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Xie H, Clarke S. Methyl esterification of C-terminal leucine residues in cytosolic 36-kDa polypeptides of bovine brain. A novel eucaryotic protein carboxyl methylation reaction. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)38660-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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540
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Tazzari PL, Zhang S, Chen Q, Sforzini S, Bolognesi A, Stirpe F, Xie H, Moretta A, Ferrini S. Targeting of saporin to CD25-positive normal and neoplastic lymphocytes by an anti-saporin/anti-CD25 bispecific monoclonal antibody: in vitro evaluation. Br J Cancer 1993; 67:1248-53. [PMID: 8512810 PMCID: PMC1968507 DOI: 10.1038/bjc.1993.233] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
This study has been designed to verify the specific toxicity of saporin, a type 1 ribosome-inactivating protein (RIP), with the same activity as ricin A chain, targeted by a bispecific monoclonal antibody (bimAb) recognising both the CD25 antigen and the RIP. The CD25 antigen is expressed by lymphoid populations upon activation and by leukaemias and lymphomas with an activated membrane phenotype (Hodgkin's lymphoma, anaplastic large cell lymphoma, adult T cell leukaemia). The bimAb-saporin mixture was tested on CD25+ targets at different bimAb and saporin concentrations. Saporin, in the presence of a bimAb concentration of 10(-9) M, inhibited protein synthesis by CD25+ neoplastic lymphocytes (L540 and MT2 cell lines) with IC50S (concentrations giving 50% of inhibition) ranging from 8 x 10(-12) M to 3 x 10(-11) M. The saporin-bimAb mixture was also effective in blocking the phytohaemagglutinin-driven proliferation of normal lymphocytes, whereas it displayed the same level of toxicity exerted by saporin alone on an irrelevant CD25-negative cell line (EBV-infected B lymphoblastoid cell line). From these results it is possible to envisage a clinical use of this bimAb as a cytotoxic agent for CD25+ leukaemias and lymphomas, as well as an immunosuppressive agent for severe immune disorders such as graft-vs-host disease (GVHD) and transplanted organ rejection.
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541
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Zeng ZC, Tang ZY, Xie H, Liu KD, Lu JZ, Chai XJ, Wang GF, Yao Z, Qian JM. Radioimmunotherapy for unresectable hepatocellular carcinoma using 131I-Hepama-1 mAb: preliminary results. J Cancer Res Clin Oncol 1993; 119:257-9. [PMID: 8382704 DOI: 10.1007/bf01212721] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Twenty-three patients with surgically verified unresectable hepatocellular carcinoma (HCC) have been treated by intrahepatic arterial administration of 131I-labeled anti-HCC monoclonal antibody (Hepama-1) combined with hepatic artery ligation. Radioimmunoimaging demonstrated that the median tumor/liver ratio was 2.1 (1.1-3.6) at day 5. A decline in alpha-fetoprotein level and shrinkage of tumor were observed in 75% (12/16) and 78% (18/23) of patients respectively. Sequential resection was done in 11 patients (48%) after treatment. The surgical specimens revealed massive necrosis of tumor, but residual cancer cells were found at the edge of the specimens. Anti-antibody was determined in 43% (10/23) of patients 2-4 weeks after the administration of 131I-Hepama-1 mAb. No marked toxic effects were noted. It is suggested that 131I-Hepama-1 mAb might be of value as one of the multimodality treatments for unresectable HCC.
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542
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Abstract
The invasion of gingival epithelial cells by certain pathogenic periodontal bacteria may account for their presence within diseased gingival tissue. To dissect the initial steps of a potential invasion pathway for the periodontal pathogen Porphyromonas gingivalis, laboratory and clinical bacterial isolates were tested for their interactions with a human oral epithelial cell line (KB). Several P. gingivalis strains immobilized on filters could bind oral epithelial cells. Quantitative adherence assays supported these results. The invasion of epithelial cells by P. gingivalis 33277 was measured by assay and confirmed by transmission electron microscopy. These preliminary results demonstrate that certain P. gingivalis strains are capable of internalization by human oral epithelial cells in vitro.
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543
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Kempa K, Bakshi P, Xie H, Schaich WL. Current-driven plasma instabilities in solid-state layered systems with a grating. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 47:4532-4536. [PMID: 10006601 DOI: 10.1103/physrevb.47.4532] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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544
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Xie H, Tsybenko VA, Johnson MV, Lautt WW. Insulin resistance of glucose response produced by hepatic denervations. Can J Physiol Pharmacol 1993; 71:175-8. [PMID: 8319140 DOI: 10.1139/y93-024] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This study investigated the glucose response to insulin infused after hepatic denervation. Hepatic denervations were performed on 13 anesthetized cats at different levels: (i) surgical hepatic anterior plexus denervation, (ii) chemical total hepatic denervation by painting phenol on the tissues around the portal vein, bile duct, common hepatic artery, and hepatic ligaments, and (iii) bilateral vagotomy. Sham denervations were performed on 9 animals. Before denervation and after each performance of denervations, insulin (100 mU/kg, i.v.) was infused. Plasma glucose concentrations were analyzed at 15, 30, 45, and 60 min after insulin infusion. Hepatic anterior plexus denervation produced a significant reduction in insulin effectiveness. Phenol denervation and bilateral vagotomy failed to further significantly alter the level of insulin resistance developed by hepatic anterior plexus denervation. These observations demonstrate that the effect of insulin on glucose regulation is markedly reduced in the absence of hepatic anterior plexus innervation, suggesting that hepatic nerve function is necessary for the normal glucose response to insulin. Furthermore, the hepatic nerves of relevance appear to reach the liver primarily, if not exclusively, by the anterior hepatic plexus.
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545
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Chen Q, Sun P, Prigione I, Xie H, Ferrini S. Targeting of «T» Lymphocytes against Human Hepatoma Cells by a Bispecific Monoclonal Antibody: Role of Different Lymphocyte Subsets. TUMORI JOURNAL 1992; 78:79-86. [PMID: 1326141 DOI: 10.1177/030089169207800204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In an attempt to construct bispecific monoclonal antibodies (bimAbs) able to target cytotoxic T lymphocytes against human hepatoma cells, an HGPRT-deficient mutant of the Hepama-6 hybridoma, which produces an antihuman-hepatoma mAb, was directly fused with splenocytes from Balb/C mice immunized by a polyclonal cytotoxic T-cell line. Hybrid hybridomas were selected in HAT medium, and their supernatants were directly screened for the ability to induce IL-2-cultured cytotoxic T lymphocytes to kill hepatoma cells in a 51Cr-release assay. The selected hybrid hybridoma, termed DQ-33, secretes a bimAb, which reacts with a CD3-associated determinant. When resting peripheral-blood lymphocytes were used as effector cells, virtually no cytolytic activity could be induced by DQ-33, whereas phytohemagglutinin-activated lymphocytes that had been expanded in vitro in IL-2-containing medium could be efficiently targeted against hepatoma cells. Targeting by DQ-33 bimAb was analyzed on different subsets of IL-2-cultured lymphocytes. It was evident that CD+4–8+ TCRα/β+ and CD3+4–8-TCRγ/δ+ lymphocytes were efficiently induced by bimAb to lyse human hepatoma cells, whereas no induction of cytolysis could be observed when CD3 + 4+8-TCRα/β+ cells were used as effectors. DQ-33 bimAb was also able to induce lymphokine secretion (IL-2, GM-CSF and TNF-α) by all the different subsets of lymphocytes analyzed in the presence of target cells expressing the relevant antigen, independent of the expression of cytolytic activity.
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546
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Xie H, Triggle CR. The effects of changes in pO2 on endothelium-dependent and -independent relaxations of the human umbilical artery and rat aorta. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1992; 311:399-400. [PMID: 1529775 DOI: 10.1007/978-1-4615-3362-7_53] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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547
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Wang GD, Zhao DY, Xie H, Li ZW. Techniques for intra-axonal recording of electrical activity from single nerve fiber in vitro and in situ. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 1991; 11:208-10. [PMID: 1819030 DOI: 10.1007/bf02888152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The method usually applied for recording the electrical activity of single nerve fiber is extracellular recording on isolated single nerve fiber. It is difficult to obtain stable and satisfactory results from direct intracellular recording of single nerve fiber, except for some special biological materials, such as Loligo giant axon. We present in this paper a technique for recording intracellular resting membrane potential and action potential from single nerve fiber both in vitro and in situ, using glass microelectrode and a special mirror-base plate for fixing the preparation. Besides, we also report a method for labelling single nerve fiber by means of injection of HRP into the axon.
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548
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Xie H, Gibbons RJ, Hay DI. Adhesive properties of strains of Fusobacterium nucleatum of the subspecies nucleatum, vincentii and polymorphum. ORAL MICROBIOLOGY AND IMMUNOLOGY 1991; 6:257-63. [PMID: 1820561 DOI: 10.1111/j.1399-302x.1991.tb00488.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This study surveyed some adhesive properties of strains of Fusobacterium nucleatum representative of the 3 recently defined groups or subspecies that could relate to their colonization and virulence. With one exception, F. nucleatum strains agglutinated sheep erythrocytes, but the quantity of bacteria required and the sensitivity of the hemagglutination reactions to inhibition by 0.05 M galactose or arginine varied between strains, and did not exhibit clear-cut correlations with subspecies. Neuraminidase treatment of erythrocytes generally enhanced the hemagglutinating activity of most strains, but trypsin treatment had no effect. Strains of F. nucleatum also attached in moderate numbers to buccal epithelial cells. Treatment of the epithelial cells with neuraminidase or with trypsin increased the numbers of all Fusobacterium strains that attached. Treatment of hydroxyapatite (HA) beads with submandibular or parotid saliva also promoted the adhesion of all strains of F. nucleatum studied. Treatment of HA with human serum or albumin produced a selective effect. Adhesion of some strains was promoted by serum and albumin treatment, and that of other strains was unaffected. Adhesion of all strains of F. nucleatum was enhanced to statherin-treated HA, whereas HA treated with salivary proline-rich protein-1 did not foster F. nucleatum attachment. Three of 4 strains of the subspecies vincentii, and each of 2 polymorphum strains studied exhibited strong adhesion to HA treated with either human type I or type IV collagen. However, only 1 of 5 strains of the subspecies nucleatum bound well to collagen-treated HA.(ABSTRACT TRUNCATED AT 250 WORDS)
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549
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Wang QC, Ying WB, Xie H, Zhang ZC, Yang ZH, Ling LQ. Trichosanthin-monoclonal antibody conjugate specifically cytotoxic to human hepatoma cells in vitro. Cancer Res 1991; 51:3353-5. [PMID: 1647265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A plant single-chain ribosome-inactivating protein derived from the root tuber of Trichosanthes kirilowii, termed trichosanthin (TCS), was modified with 2-iminothiolane. It was not like trichokirin, a ribosome-inactivating protein derived from the seeds of the same plant, in that TCS retained full activity when 1.5 sulfhydryl groups were introduced into each TCS molecule by 2-iminothiolane modification. The 2-iminothiolane-TCS was conjugated to Hepama-1, a monoclonal antibody directed against human hepatoma with a cross-linking reagent, N-succinimidyl-3-(2-pyridyl)-dithiopropionate. The hepatoma cytotoxicity of the immunotoxin, TCS-Hepama-1, was 500-fold higher than that of free TCS and only 1 log lower than that of free ricin. However, the immunotoxin was approximately 600-fold less cytotoxic to HeLa cells. The results suggested that the immunotoxin was a potent and quite specific antihepatoma agent and might have considerable potential in hepatoma therapy.
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550
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Chaturvedi L, Zhao X, Ramayya AV, Hamilton JH, Kormicki J, Zhu S, Girit C, Xie H, Gao W, Jiang Y, Petrovici A, Schmid KW, Faessler A, Johnson NR, Baktash C, Lee IY, McGowan FK, Halbert ML, Riley MA, McNeill JH, Kortelahti MO, Cole JD, Piercey RB, Jin HQ. Tests of microscopic calculations of multiple band structures and large deformations in 68Ge and 72Se. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1991; 43:2541-2545. [PMID: 9967313 DOI: 10.1103/physrevc.43.2541] [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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