8101
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Yang Y, Chisholm GD, Habib FK. Epidermal growth factor and transforming growth factor alpha concentrations in BPH and cancer of the prostate: their relationships with tissue androgen levels. Br J Cancer 1993; 67:152-5. [PMID: 7678977 PMCID: PMC1968204 DOI: 10.1038/bjc.1993.26] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We measured immunoreactive EGF and TGF alpha in prostate tissue extracts obtained from 19 patients with benign prostatic hyperplasia (BPH) and 19 with cancer of the prostate (CaP). Whilst both BPH and CaP expressed EGF (BPH = 195.61 +/- 19.94 ng g-1 protein; CaP = 235.60 +/- 24.45 ng g-1 protein) and TGF alpha (BPH = 92.57 +/- 7.60 ng g-1 protein; CaP = 100.73 +/- 15.47 ng g-1 protein) in equal concentrations, the levels of EGF in any tissue extract were on average twice those of TGF alpha. Furthermore analysis of the individual growth factor data revealed a direct correlation between EGF and TGF alpha in both BPH (r = 0.72, P < 0.001) and CaP (r = 0.69, P < 0.001). When the tumours were classified according to their Gleason score, a slight but significant increase in growth factor concentrations was noted as the tumour became less differentiated. We also measured the concentrations of testosterone and dihydrotestosterone (DHT) in prostate extracts with a view of elucidating the relationship between androgen and growth factors in this gland. There was a small positive correlation only between testosterone and EGF (r = 0.62, P < 0.05) and testosterone and TGF alpha (r = 0.61, P < 0.05) in CaP. The absence of any similar correlation in BPH where DHT becomes the predominant hormone may suggest an indirect role for testosterone in the regulation of growth factor production.
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8102
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Yang Y, Chute CG. Words or concepts: the features of indexing units and their optimal use in information retrieval. PROCEEDINGS. SYMPOSIUM ON COMPUTER APPLICATIONS IN MEDICAL CARE 1993:685-9. [PMID: 8130562 PMCID: PMC2850662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Words or Concepts, which are a better choice for indexing the contents of documents? The answer depends on what method is used for retrieval. This paper studies the effects of using canonical concepts versus document words in different retrieval systems with a testing collection of MEDLINE documents. In our tests, for a retrieval system which does not use any human knowledge, using words yielded better retrieval results, while using concepts suffered from a vocabulary difference between canonical expressions of concepts and non-canonical words in queries or documents. For a system which depends on the UMLS synonym set for a mapping from queries or documents to canonical concepts, the retrieval results were slightly better than the case of not using the synonyms, but still worse than the systems using words. For the systems which automatically "learn" empirical connections between words and concepts from examples in the testing collection, the vocabulary problem was effectively solved, and the results of using concepts were competitive or better, compared to those using words.
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8103
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Yang Y, Kwon HB, Peng HP, Shih MC. Stress responses and metabolic regulation of glyceraldehyde-3-phosphate dehydrogenase genes in Arabidopsis. PLANT PHYSIOLOGY 1993; 101:209-16. [PMID: 8278495 PMCID: PMC158666 DOI: 10.1104/pp.101.1.209] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We report here effects of three environmental conditions, heat shock, anaerobic treatment, and carbon source supply, on expression of nuclear genes encoding chloroplast (GapA and GapB) and cytosolic (GapC) glyceraldehyde-3-phosphate dehydrogenase from Arabidopsis thaliana. The steady-state mRNA level of the GapC increased when Arabidopsis plants were transferred from normal growth condition to heat-shock, anaerobiosis, or increased sucrose supply conditions. In contrast, the steady-state mRNA levels for GapA and GapB genes were unaffected or decreased transiently under the same treatments. To identify the cis-acting regulatory elements, transgenic tobacco plants containing a 820-bp GapC 5'-flanking DNA fragment and beta-glucuronidase (Gus) fusion were constructed. Analyses of these transgenic plants indicate that this 820-bp DNA fragment is sufficient to confer both heat-shock and anaerobic responses. These results suggest that transcriptional level control is involved in regulation of GapC expression under these stress conditions. Histochemical analysis of Gus activity indicates that expression of the GapC is cell-type specific and is probably linked to the metabolic activity of the cells.
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8104
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Yang Y, Luo YS, Weaver JH. Scanning-tunneling-microscopy study of Ge/GaAs(110). II. Coalescence and layer-by-layer growth. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:15395-15403. [PMID: 10003658 DOI: 10.1103/physrevb.46.15395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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8105
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Jackson MR, Song ES, Yang Y, Peterson PA. Empty and peptide-containing conformers of class I major histocompatibility complex molecules expressed in Drosophila melanogaster cells. Proc Natl Acad Sci U S A 1992; 89:12117-21. [PMID: 1465448 PMCID: PMC50709 DOI: 10.1073/pnas.89.24.12117] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Transfected Drosophila melanogaster cells can express large quantities of class I major histocompatibility complex molecules. Such molecules lack endogenous peptides because the Drosophila cells are devoid of proteins necessary for intracellular peptide loading. The empty molecules are efficiently expressed on the cell surface and can acquire extracellular peptides. The conformation and stability of empty murine class I molecules are determined by the source of beta 2-microglobulin. All beta 2-microglobulin-induced conformers of empty heavy chains seem to be unified in a common rigid conformation on peptide binding.
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8106
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Yang Y, Luo YS, Weaver JH. Scanning-tunneling-microscopy study of Ge/GaAs(110). I. Initial nucleation and growth. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:15387-15394. [PMID: 10003657 DOI: 10.1103/physrevb.46.15387] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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8107
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Yang Y, Gao Z, Guzmán-Verduzco LM, Tachias K, Kupersztoch YM. Secretion of the STA3 heat-stable enterotoxin of Escherichia coli: extracellular delivery of Pro-STA is accomplished by either Pro or STA. Mol Microbiol 1992; 6:3521-9. [PMID: 1474896 DOI: 10.1111/j.1365-2958.1992.tb01787.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The methanol-soluble, heat-stable enterotoxin of Escherichia coli is a protease-resistant extracellular peptide which is synthesized as a 72-amino-acid precursor Pre-Pro-STA3. The specific roles of Pre (19 amino acids), Pro (34 amino acids) and STA3 (19 amino acids) in the secretion process were studied by functionally deleting each of the three domains. Deletion of the Pre signal sequence resulted in a short-lived cell-associated molecule with an M(r) equivalent to that of Pro-STA3. Deletion of Pro (i.e., Pre-STA3) resulted in the rapid extracellular accumulation of STA3; the periplasmic intermediate found in the secretion of the wild-type toxin was undetected. Deletion of the STA3 domain resulted in a cell-associated Pre-Pro peptide; with time this form converted to periplasmic Pro which later became extracellular. When DNA encoding either STA3, by itself, or Pro-STA3 (lacking the signal peptide) was expressed, these peptides were degraded intracellularly, with no periplasmic or extracellular forms detected. The results presented demonstrate that the signal peptide (Pre) is essential even for the export of small peptides to the periplasm, and that its absence causes the STA3 domain to become susceptible to intracellular proteases. The rapid degradation of intracellular STA3 indicates that its proteolytic resistance is acquired in a compartment other than the cytoplasm. The results also show that after the Pre domain is proteolytically cleaved from Pre-STA3 and Pre-Pro, the STA3 and Pro peptides can exit to the culture supernatant.(ABSTRACT TRUNCATED AT 250 WORDS)
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8108
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Yang Y, Yang Y, Su X. [Endogenous uveitis in senior patients]. YAN KE XUE BAO = EYE SCIENCE 1992; 8:169-72. [PMID: 1306497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Forty-seven cases of endogenous uveitis aged 60 and above were analyzed in the retrospective study. The result shows males are more than females (1.2:1). Among the 47 cases, 28 cases (59.57%) are anterior uveitis, 18 cases (38.30%) are panuveitis. Only 1 case (2.13%) is posterior uveitis. Immediated-type uveitis is not found. Besides, 34 cases are non-granulomatosis type, more than the cases with granulomatosis type (13 cases). The major complications are secondary glaucoma (22 cases) and complicated cataract (16 cases). Immunological tests to the patients showed the unbalance of immune-regulation was mostly complicated by immune-related sickness. The cure rate was 40.58%. The invalid and deteriorative rate was 17.39%. 62.32% of the patients had the vision acuity lower than 0.3 after the treatment.
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8109
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Shan B, Zhu X, Chen PL, Durfee T, Yang Y, Sharp D, Lee WH. Molecular cloning of cellular genes encoding retinoblastoma-associated proteins: identification of a gene with properties of the transcription factor E2F. Mol Cell Biol 1992; 12:5620-31. [PMID: 1448092 PMCID: PMC360501 DOI: 10.1128/mcb.12.12.5620-5631.1992] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The retinoblastoma protein interacts with a number of cellular proteins to form complexes which are probably crucial for its normal physiological function. To identify these proteins, we isolated nine distinct clones by direct screening of cDNA expression libraries using purified RB protein as a probe. One of these clones, Ap12, is expressed predominantly at the G1-S boundary and in the S phase of the cell cycle. The nucleotide sequence of Ap12 has features characteristic of transcription factors. The C-terminal region binds to unphosphorylated RB in regions similar to those to which T antigen binds and contains a transactivation domain. A region containing a potential leucine zipper flanked by basic residues is able to bind an E2F recognition sequence specifically. Expression of Ap12 in mammalian cells significantly enhances E2F-dependent transcriptional activity. These results suggest that Ap12 encodes a protein with properties known to be characteristic of transcription factor E2F.
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8110
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Früh K, Yang Y, Arnold D, Chambers J, Wu L, Waters JB, Spies T, Peterson PA. Alternative exon usage and processing of the major histocompatibility complex-encoded proteasome subunits. J Biol Chem 1992; 267:22131-40. [PMID: 1429565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The finding that two subunits of the proteasome, LMP2 and LMP7, are encoded in the major histocompatibility complex (MHC) has linked the proteasome which represents a major extralysosomal proteolytic system to the processing of intracellular antigens. Here we describe a second form of the human LMP7 cDNA, LMP7-E2, which has been identified during the characterization of novel genes in the MHC. The analysis of the genome organization of LMP7 revealed that LMP7-E1 and LMP7-E2 arise by alternative exon usage. Using specific antibodies against LMP2 and LMP7, we show that they are co-expressed with class I MHC molecules as well as a putative peptide transporter. The polypeptides encoded by LMP7 and LMP2 undergo proteolytic processing when incorporated into proteasomes, and the LMP7 precursor is derived mainly from LMP7-E2. Furthermore, our data suggest that LMP7 and LMP2 are mutually dependent for their incorporation into the proteasomal complex.
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8111
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Früh K, Yang Y, Arnold D, Chambers J, Wu L, Waters J, Spies T, Peterson P. Alternative exon usage and processing of the major histocompatibility complex-encoded proteasome subunits. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)41645-6] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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8112
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Deshmukh GR, Yang Y, Tellis VA, Gerst PH. A simple cuff-suture technique for microvascular anastomosis. J Reconstr Microsurg 1992; 8:491-4. [PMID: 1453375 DOI: 10.1055/s-2007-1006735] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The use of synthetic cuffs to simplify and hasten microvascular anastomoses is offered as an alternative to conventional methods. In this study, a soft, non-irritating, silicone rubber cuff was used to construct end-to-end and end-to-side cuff-sutured anastomoses in rats. This technique was as rapid as other non-sutured anastomoses, required no assistant, and provoked no foreign-body reactions.
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8113
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Engelhardt JF, Yankaskas JR, Ernst SA, Yang Y, Marino CR, Boucher RC, Cohn JA, Wilson JM. Submucosal glands are the predominant site of CFTR expression in the human bronchus. Nat Genet 1992; 2:240-8. [PMID: 1285365 DOI: 10.1038/ng1192-240] [Citation(s) in RCA: 513] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have used in situ hybridization and immunocytochemistry to characterize the cellular distribution of cystic fibrosis (CF) gene expression in human bronchus. The cystic fibrosis transmembrane conductance regular (CFTR) was primarily localized to cells of submucosal glands in bronchial tissues from non-CF individuals notably in the serous component of the secretory tubules as well as a subpopulation of cells in ducts. Normal distribution of CFTR mRNA was found in CF tissues while expression of CFTR protein was genotype specific, with delta F508 homozygotes demonstrating no detectable protein and compound heterozygotes expressing decreased levels of normally distributed protein. Our data suggest mechanisms whereby defects in CFTR expression could lead to abnormal production of mucus in human lung.
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8114
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Yang Y. [Immune complex in the wall of the gallbladder in patients with cholelithiasis: deposition and its pathological significance]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1992; 30:645-7, 698. [PMID: 1307287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The gallbladder specimens from 53 patients with cholelithiasis were studied by immunohistochemical method. Deposition of immune complex (IC) was observed on the mucosal and glandular epithelium in 84% of patients with gallstones and 47% of patients with choledocholithiasis. IgG and C3 were the most frequent complement component demonstrated at the site of IC deposition, but Clq, factor B and C4 were also present in many cases, suggesting the local complement activation. We conclude that IC may play a pathogenetic role in the injury of the mucosa and tissue of gallbladder in patients with cholelithiasis.
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8115
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Tang L, Wen F, Yang Y, Crowe CT, Chung JN, Troutt TR. Self‐organizing particle dispersion mechanism in a plane wake. ACTA ACUST UNITED AC 1992. [DOI: 10.1063/1.858465] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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8116
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Hu XL, Yang Y, Hunt JS. Differential distribution of interleukin-1 alpha and interleukin-1 beta proteins in human placentas. J Reprod Immunol 1992; 22:257-68. [PMID: 1453390 DOI: 10.1016/0165-0378(92)90047-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta) were identified in samples of first trimester and term placentas by immunocytochemistry using two sets of polyclonal antibodies to recombinant IL-1. All samples contained the two species of IL-1, which predominated in different types of cells: IL-1 alpha was contained primarily in placental villous trophoblastic and stromal cells whereas IL-1 beta was localized to cells in fetal and maternal blood. With respect to the cellular localization of the two proteins, early and late gestation tissues were similar. Although these results were generally consistent for the two sets of antibodies, differences were noted in the binding patterns of the individual reagents. The findings in this study provide strong support for the postulate that IL-1 modulates placental development and suggest that IL-1 alpha may be the preferred species in extraembryonic tissues.
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8117
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Flavin MP, Yang Y, Riopelle RJ. The effect of hypoxia on neurotransmitter phenotype of forebrain cholinergic neurons. Brain Res 1992; 583:201-6. [PMID: 1354562 DOI: 10.1016/s0006-8993(10)80025-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The effect of hypoxia on the neurotransmitter phenotype of rat forebrain cholinergic neurons was analyzed using a dissociated fetal rat culture system. The aims of this study were to examine the feasibility of using choline acetyltransferase (ChAT) activity as a measure of cell injury and/or recovery, to measure the time course of hypoxic effects on ChAT activity, to determine how changes in ChAT activity at 48 h post-injury relate to microscopic changes and LDH release into the medium during that time, and finally to explore the possible mechanisms of hypoxic injury in this model. At exposure to 0.5-1.5% O2 there was a time-dependent decrease in ChAT activity when cells were harvested 48 h after exposure. Forty-eight hours after 8-9 h hypoxic exposure ChAT activity was 50-60% that of controls without any alteration in morphology of neurons. An 8 h exposure to hypoxic conditions caused a post-exposure time-dependent decrease in ChAT activity to 20% of control level at 72 h. Thereafter there was spontaneous recovery of phenotype to 60% of control which remained stable between 5 and 7 days post-exposure. Loss of neurotransmitter phenotype was not well correlated with other measures of cytotoxicity including morphological changes and LDH release. The loss of phenotype observed with hypoxia was mimicked by glutamate and kainate but not by NMDA. Consistent with these observations, neither APV nor AP3 significantly altered the effect of hypoxia on forebrain cholinergic neurons, while the addition of APV and CNQX in combination protected the phenotype of these neurons only if there was 50% or less loss of phenotype following hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)
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8118
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Wei J, Guo Y, Chen B, Yang Y. Significantly higher frequency of the MspI 2.2 kb allele of the Duchenne muscular dystrophy intragenic probe P-20 in the Chinese population. Hum Genet 1992; 90:149-50. [PMID: 1385293 DOI: 10.1007/bf00210761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The P-20 intragenic marker was used to test for restriction fragment length polymorphisms in unrelated Chinese patients with Duchenne or Becker muscular dystrophy or X-linked mental retardation. In addition to polymorphism at the 6.0/3.5 kb MspI allelic site, we found an independent and high frequency of polymorphism at the 2.2/1.8 kb site. This differs from results found with other populations.
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8119
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Zhou D, Yang Y, Li L, Yuan G, Chen H. [Effect of poly-saccharide sulphate on thixotropic properties of whole blood in patients with cerebral thrombosis]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1992; 23:241-4. [PMID: 1363700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
Using Low shear 30 rheometer, we measured the thixotropic parameters of blood from 30 patients suffering from cerebral thrombosis. The result showed that the yield stress (tau 0), non-Newtonian contribution of viscosity (eta s-mu) and viscosity of plasma (eta p) were significantly higher than those in the control group. Those patients were randomly divided into two groups. Each group included 15 patients. The patients in group 1 and group 2 were treated with poly-saccharide sulphate (PSS) and DX40 respectively by intravenous drip for 14 days. The results showed that tau 0, A, (eta s-mu) were significant decreased in group 1 after treatment, but no significantly change in the thixotropic parameters was found in group 2 after treatment. The total curative rate in group 1 was higher than that in group 2. These results suggest that the patients with cerebral thrombosis had evidently increased degree of RBC aggregation. PSS could decrease the aggregation of RBC more significantly than DX40 did. It was probably one of the reasons why the therapeutic effect of PSS on cerebral thrombosis was better than that of DX40.
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8120
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Critelli G, Yang Y. The nonpharmacological treatment of tachyarrhythmias--towards a new therapeutic era. Pacing Clin Electrophysiol 1992; 15:1362-7. [PMID: 1383998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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8121
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Bai W, Singh B, Yang Y, Arlinghaus RB. Evidence for interaction between v-Mos and a p34cdc2 isoform, p35cdk. Oncogene 1992; 7:1757-63. [PMID: 1323818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The c-mos gene product (c-Mos) encodes a serine/threonine kinase required for activation of pre-MPF (maturation-promoting factor) to MPF in oocytes undergoing meiosis and also for stabilization of MPF leading to metaphase arrest in unfertilized eggs. In order to determine whether the v-mos gene product (v-Mos) causes neoplastic transformation via interaction with cell cycle control elements, we have searched for proteins that interact with v-Mos. Extracts of NIH3T3 cells transformed by v-Mos encoded by Moloney murine sarcoma virus (Mo-MuSV) were examined by gel filtration, by immunoprecipitation with antibodies to a conserved region of p34cdc2, and by binding to beads that contain cross-linked p13suc1, a protein known to bind p34cdc2. Gel filtration detected a 500-kDa complex that contained v-Mos and a p34cdc2 isoform, termed p35cdk. The 500-kDa macromolecular complex also exhibited histone H1 phosphorylation activity, consistent with the presence of a cdc2 isoform. The identity of p35cdk is based on its recognition by anti-cdc2 PSTAIR but not by anti-cdc2 C-terminal antibodies, which detect authentic p34cdc2. Structures containing v-Mos and p35cdk were also detected by experiments involving co-immunoprecipitation of v-Mos with anti-cdc2 PSTAIR antibodies. Furthermore, both v-Mos and the p35cdk co-precipitated with p13suc1-Sepharose beads. Our findings raise the possibility of a v-Mos-p35cdk regulatory interaction in cells transformed by Mo-MuSV.
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8122
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Kuwano H, Hashizume M, Yang Y, Kholoussy AM, Matsumoto T. The nature of inner cellular lining of the expanded polytetrafluoroethylene vascular graft: immunohistochemical study. Int Surg 1992; 77:186-9. [PMID: 1399366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Histological and immunohistochemical studies of the healing processes of expanded polytetrafluoroethylene (PTFE) vascular graft were performed. In the animal experiment, endothelial cell lining, confirmed by immunohistochemical staining for anti-Factor VIII related antigen, existed nearly over all of the pannus. The endothelial cells also formed to some extent over the graft without pannus. Endothelialization showed a close dependency on the surface condition of the underlying tissue rather than on a time factor. In the human experiment, an endothelial island was observed in the middle portion of the graft in one case, supporting the hypothesis of the blood stream origin of endothelial cells.
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8123
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Luo YS, Yang Y, Weaver JH. Mechanisms for adatom-induced disruption of Bi2Sr2CaCu2O8(001): Scanning-tunneling-microscopy studies of Ag-, Au-, and Cr-overlayer growth. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:1114-1121. [PMID: 10003299 DOI: 10.1103/physrevb.46.1114] [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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8124
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Yang Y, Früh K, Chambers J, Waters JB, Wu L, Spies T, Peterson PA. Major histocompatibility complex (MHC)-encoded HAM2 is necessary for antigenic peptide loading onto class I MHC molecules. J Biol Chem 1992; 267:11669-72. [PMID: 1339432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The mutant murine lymphoma cell line RMA-S is unable to present endogenous antigens due to its inability to efficiently assemble class I major histocompatibility complex molecules and antigenic peptides. Therefore, it has been suggested that RMA-S cells are defective either in peptide generation or in peptide transport into the endoplasmic reticulum, where class I major histocompatibility complex molecule assembly is believed to occur. As proteasomes and the putative peptide transporters HAM1 and HAM2 have been implicated in class I antigen processing, we have investigated their expression in RMA-S and its wild-type counterpart RMA. Both proteasomes and HAM1 proteins are expressed at similar levels and show identical subcellular distributions in the two cell lines. However, only one copy of the HAM2 gene is present in RMA-S cells, and it contains a point mutation that leads to a premature stop codon. Thus, the HAM2 protein is absent from RMA-S cells. These data demonstrate that HAM2 is essential for peptide loading onto class I molecules.
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8125
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Yang Y, Luo YS, Weaver JH. Anisotropic kinetics in overlayer growth: A scanning-tunneling-microscopy study of Ge/GaAs(110). PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:13803-13806. [PMID: 10001490 DOI: 10.1103/physrevb.45.13803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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8126
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Yang Y, Chen Z, Xu Y, Kou W, Gao R, Yang H. Quantitative assessment of regional wall motion abnormalities with 2DE in cases of myocardial infarction. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1992; 7:108-11. [PMID: 1450392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The severity, extent and localization of regional wall motion abnormalities (RWMA) were quantitatively assessed with apical biplane two-dimensional echocardiography (2DE) using a fixed-axis system, ten-segment division area method in 56 patients with old myocardial infarction (OMI). RWMA were found to be more severe in the anterior wall MI (AWMI) group than in the inferoposterior wall MI (IWMI) group and most severe in the extensive AWMI with ventricular aneurysm (EAWMI with VA) group; the extent of RWMA was smallest in the IWMI group, significantly larger in the AWMI group, and largest in the EAWMI with VA group. The location of the RWMA segments showed group-specific tendencies. For example, both coronal and sagittal apices were much more frequently involved in both the EAWMI with VA and the AWMI groups than in the IWMI group (100%, 87% and 0%, respectively, all P < 0.001). The results demonstrated that quantitative analysis of RWMA using 2DE in cases of MI is accurate and feasible.
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8127
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Wang S, Feng N, Li J, Yang Y, Liu X. Flow cytometry for analyzing changes in irradiated and heated HeLa S3 cells. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 1992; 7:82-5. [PMID: 1450397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In the present study, we have compared the distribution in various phases, DNA content, cell survival and ultrastructure of HeLa S3 cells after irradiation and/or hyperthermia. After 220 KV X-ray irradiation, the Do of the survival curve was 0.94 Gy, Dq was 1.3 Gy, and N was 4.26. After Ir-192 gamma-ray irradiation, the Do of the survival curve was 2.26 Gy, Dq was 3.9 Gy, and N was 5.7. The Do of the survival curve of HeLa S3 cells after treatment at 43.5 degrees C and 44 degrees C was 2.2 min and 1.6 min, respectively. Ultrastructural changes were also observed. The marked increase of the DNA content after 6 Gy irradiation corresponded with changes of distribution in various phases, which indicated a delay in the G2 + M phase. The survival fraction after 6 Gy irradiation was less than 1%. The changes of cell cycle distribution after Ir-192 irradiation were similar to those seen after X-ray exposure. The delay of G2 + M phase after hyperthermia was dose-dependent. An obvious delay of the G2 + M phases was also observed at 24 h after treatment with X-rays plus hyperthermia.
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8128
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Li L, Chen H, Zhong G, Yang Y, Tang S, Zhang F, Zhou T, Wang M, Huo Y. [Thixotropic properties of whole blood in children with congenital heart disease]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1992; 23:137-9. [PMID: 1452142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The thixotropic parameters of whole blood in two groups of children with congenital heart disease (CHD) were measured. Group 1. cyanotic heart disease (CCHD), 20 cases; Group 2. acyanotic heart disease (ACHD), 30 cases. Fifty healthy children were controls matched with the patients in sex and age. Their thixotropic parameters were compared; the paired t-test was used. In the children with CCHD, the hematocrit (HCT), the yield stress (tau 0) the Newtonian contribution of viscosity (mu), the equilibrium value of the structural parameter (A), the apparent viscosity at 2.37 sec-1 (eta s) and the Non-Newtonian contribution of viscosity (eta s-mu) were significantly higher than those in corresponding control groups. In the children with ACHD, only the values of tau 0, eta s-mu, and eta s were higher than those in control groups. All of the thixotropic parameters in CCHD group were significantly higher than those in ACHD group. Thus we described quantitatively CHD in terms of thixotropy of blood. The thixotropic parameters of blood could be used as indexes of severity for pathologic changes of CHD.
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8129
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Yang Y, Waters JB, Früh K, Peterson PA. Proteasomes are regulated by interferon gamma: implications for antigen processing. Proc Natl Acad Sci U S A 1992; 89:4928-32. [PMID: 1594596 PMCID: PMC49201 DOI: 10.1073/pnas.89.11.4928] [Citation(s) in RCA: 140] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Class I major histocompatibility complex (MHC) molecules present antigenic peptides of cytoplasmic origin to T cells. As the lengths of these peptides seem restricted to eight or nine amino acids, an unusual proteolytic system must play a role in antigen processing. Proteasomes, a major extralysosomal proteolytic system, are responsible for the degradation of cytoplasmic proteins. We demonstrate that several proteasomal subunits, including MHC-encoded subunits, are regulated by interferon gamma. These data and the finding that MHC-encoded and other interferon gamma-regulated proteasomal subunits are uniquely associated with proteasomes strongly suggest that the immune system has recruited proteasomes for antigen processing.
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8130
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Yang Y, Rasmussen BA, Bush K. Biochemical characterization of the metallo-beta-lactamase CcrA from Bacteroides fragilis TAL3636. Antimicrob Agents Chemother 1992; 36:1155-7. [PMID: 1510410 PMCID: PMC188856 DOI: 10.1128/aac.36.5.1155] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The CcrA beta-lactamase from Bacteroides fragilis TAL3636 was cloned into Escherichia coli and purified from inclusion bodies. This group 3 metalloenzyme hydrolyzed most beta-lactam antibiotics, including cephamycins and carbapenems. Following inhibition by chelators, enzyme activity was recovered with the cations Zn2+ and Co2+. Clavulanate and sulbactam were activators; tazobactam at 10 microM inactivated the enzyme.
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8131
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Swarup S, Yang Y, Kingsley MT, Gabriel DW. An Xanthomonas citri pathogenicity gene, pthA, pleiotropically encodes gratuitous avirulence on nonhosts. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 1992; 5:204-13. [PMID: 1421509 DOI: 10.1094/mpmi-5-204] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The pathogenicity gene, pthA, of Xanthomonas citri is required to elicit symptoms of Asiatic citrus canker disease; introduction of pthA into Xanthomonas strains that are mildly pathogenic or opportunistic on citrus confers the ability to induce cankers on citrus (S. Swarup, R. De Feyter, R. H. Brlansky, and D. W. Gabriel, Phytopathology 81:802-809, 1991). The structure and the function of pthA in other xanthomonads and in X. citri were further investigated. When pthA was introduced into strains of X. phaseoli and X. campestris pv. malvacearum (neither pathogenic to citrus), the transconjugants remained nonpathogenic to citrus and elicited a hypersensitive response (HR) on their respective hosts, bean and cotton. In X. c. pv. malvacearum, pthA conferred cultivar-specific avirulence. Structurally, pthA is highly similar to avrBs3 and avrBsP from X. c. pv. vesicatoria and to avrB4, avrb6, avrb7, avrBIn, avrB101, and avrB102 from X. c. pv. malvacearum. Surprisingly, marker-exchanged pthA::Tn5-gusA mutant B21.2 of X. citri specifically lost the ability to induce the nonhost HR on bean, but retained the ability to induce the nonhost HR on cotton. The loss of the ability of B21.2 to elicit an HR on bean was restored by introduction of cloned pthA, indicating that the genetics of the nonhost HR may be the same as that found in homologous interactions involving specific avr genes. In contrast with expectations of homologous HR reactions, however, elimination of pthA function (resulting in loss of HR) did not result in water-soaking or even moderate levels of growth in planta of X. citri on bean; the nonhost HR, therefore, may not be responsible for the "resistance" of bean to X. citri and may not limit the host range of X. citri on bean. The pleiotropic avirulence function of pthA and the heterologous HR of bean to X. citri are both evidently gratuitous.
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8132
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Tan Y, He XT, Chen SG, Yang Y. Pattern form and homoclinic structure in Zakharov equations. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 45:6109-6112. [PMID: 9907712 DOI: 10.1103/physreva.45.6109] [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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8133
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Wang XF, Li ZA, Cheng TO, Deng YB, Wang JE, Yang Y. Biplane transesophageal echocardiography: an anatomic-ultrasonic-clinical correlative study. Am Heart J 1992; 123:1027-38. [PMID: 1549967 DOI: 10.1016/0002-8703(92)90714-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In 427 subjects TEE was performed with either a uniplane or biplane transducer; in seven cadavers the cardiac anatomic segments were observed in several levels and directions. Nine transverse and six longitudinal views were compared with the corresponding cardiac anatomic segments. Based on this correlative study, the levels of segments, insertion depth, anatomic structure identification, image characteristics, clinical applications, and the advantages as well as the limitations of biplane TEE are discussed.
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8134
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Yang Y, Lin Z, Greco C, Ciccaglioni A, Sinatra R, Nigri A, Critelli G. Transcatheter ablation of the accessory pathway in 2 patients with life-threatening tachyarrhythmias. CARDIOLOGIA (ROME, ITALY) 1992; 37:291-6. [PMID: 1521254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Successful transcatheter ablation of an accessory pathway in 2 patients with life-threatening tachyarrhythmias is reported. In both cases, electrophysiological evaluation documented the posterior septal location of the anomalous atrioventricular connection. Radiofrequency current energy was delivered just below the coronary sinus orifice, and resulted in disappearance of preexcitation. During the follow-up, both patients remained free from tachyarrhythmias on no medication, and serial electrocardiographic recordings confirmed the persistent absence of preexcitation. It is concluded that ablation of accessory pathways can be accomplished easily and without risk by means of the radiofrequency catheter technique. This therapeutic modality requires a short hospitalization and can be recommended as the first option in patients with the Wolff-Parkinson-White syndrome.
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8135
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Jin H, Oksenberg D, Ashkenazi A, Peroutka SJ, Duncan AM, Rozmahel R, Yang Y, Mengod G, Palacios JM, O'Dowd BF. Characterization of the human 5-hydroxytryptamine1B receptor. J Biol Chem 1992; 267:5735-8. [PMID: 1348246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
We report the cloning of a human gene encoding the 5-hydroxytryptamine1B receptor. The receptor has the characteristics of a G-protein-linked receptor and is most homologous to the human 5-HT1D receptor. This human 5-HT receptor gene, most abundantly expressed in striatum, is localized on chromosome 6, at 6q13, and the gene encoding the 5-HT1D receptor is localized on chromosome 1. Radioligand studies indicate that the affinity of [3H]5-HT is 16 +/- 2 nM. Drug competition studies indicate that the receptor displays high affinity (i.e. less than 40 nM) for 5-HT, 5-carboxyamidotryptamine, methiothepin, and metergoline.
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MESH Headings
- Amino Acid Sequence
- Animals
- Autoradiography
- Base Sequence
- Binding, Competitive
- Blotting, Northern
- Blotting, Southern
- Brain/metabolism
- Chromosomes, Human, Pair 6
- Cloning, Molecular
- DNA/genetics
- DNA/isolation & purification
- Genomic Library
- Humans
- Molecular Sequence Data
- Oligodeoxyribonucleotides
- Organ Specificity
- Pituitary Gland/metabolism
- Polymerase Chain Reaction/methods
- Polymorphism, Restriction Fragment Length
- RNA, Messenger/genetics
- RNA, Messenger/isolation & purification
- Rats
- Receptors, Serotonin/analysis
- Receptors, Serotonin/genetics
- Receptors, Serotonin/metabolism
- Recombinant Proteins/metabolism
- Restriction Mapping
- Serotonin/metabolism
- Tritium
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8136
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Jin H, Oksenberg D, Ashkenazi A, Peroutka S, Duncan A, Rozmahel R, Yang Y, Mengod G, Palacios J, O'Dowd B. Characterization of the human 5-hydroxytryptamine1B receptor. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42612-9] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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8137
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Bai W, Singh B, Yang Y, Ramagli LS, Nash M, Herzog NK, Arlinghaus RB. The physical interactions between p37env-mos and tubulin structures. Oncogene 1992; 7:493-500. [PMID: 1532247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The c-mos protein has been reported to be complexed with tubulin and to co-localize with microtubules in unfertilized Xenopus eggs as well as in NIH3T3 cells transformed by the Xenopus c-mos gene. We performed experiments to determine whether the viral mos protein, p37v-mos, also associates with tubulin. Both mouse c-mos and v-mos proteins synthesized in vitro co-polymerized with tubulin. Upon incubation at 37 degrees C, essentially all of the mos protein (both viral and cellular) co-polymerized with tubulin, while more than 50% of the tubulin remained in the depolymerized state. The mos-tubulin interaction was specific, as indicated by the insolubility of the v-mos protein following a second cycle of temperature-dependent depolymerization/polymerization. Beta-tubulin was shown to co-precipitate with p37v-mos and to be phosphorylated by the mos kinase in vitro. Although both v-mos and c-mos proteins co-polymerize with tubulin, p37v-mos behaved differently from p39c-mos on gel filtration columns under conditions that favor disassembly of microtubules. Like Xenopus c-mos, the bulk of the mouse c-mos protein synthesized in vitro appeared in structures that fractionate at about 500 kDa. In contrast to c-mos, the majority of the v-mos protein, either isolated from stably transformed NIH3T3 cells or synthesized in vitro, eluted in the 100 kDa fraction, co-fractionating with tubulin dimers. Therefore, the v-mos protein appears to have a higher affinity for unpolymerized tubulin than c-mos, under conditions that favor disassembly of microtubules.
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8138
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Hayden PJ, Welsh CJ, Yang Y, Schaefer WH, Ward AJ, Stevens JL. Formation of mitochondrial phospholipid adducts by nephrotoxic cysteine conjugate metabolites. Chem Res Toxicol 1992; 5:232-7. [PMID: 1643252 DOI: 10.1021/tx00026a013] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Nephrotoxic cysteine conjugates derived from a variety of halogenated alkenes are enzymatically activated via the beta-lyase pathway to yield reactive sulfur-containing metabolites which bind covalently to cellular macromolecules. Mitochondria contain beta-lyase enzymes and are primary targets for binding and toxicity. Previously, mitochondrial protein and/or DNA have been considered as molecular targets for cysteine conjugate metabolite binding. We now report that metabolites of nephrotoxic cysteine conjugates form covalent adducts with rat kidney mitochondrial phospholipids. Rat kidney mitochondria were incubated with the 35S-labeled conjugates S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC), S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC), S-(1,2-dichlorovinyl)-L-cysteine, and S-(1,2,3,4,4-pentachlorobutadienyl)-L-cysteine. Quantitation of metabolite binding to whole mitochondria and to mitochondrial protein and lipid fractions revealed that as much as 42% of the 35S-label associated with the mitochondria was found in the lipid fraction. Total lipids were also extracted from 35S-treated mitochondria and separated by thin-layer chromatography. 35S-Containing metabolites were found in the lipid fractions from mitochondria treated with each of the conjugates. Lipids from both [35S]CTFC- and [35S]-TFEC-treated mitochondria contained major 35S-labeled lipid adducts which had similar mobility by thin-layer chromatography. Fatty acid analysis, 19F and 31P NMR spectroscopy, and mass spectrometric analyses confirmed that the major TFEC and CTFC adducts are thioamides of phosphatidylethanolamine.
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8139
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Yang Y, Luo YS, Weaver JH. Ag crystallite formation and coalescence on hydrogen-terminated GaAs(110). PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:3606-3611. [PMID: 10001941 DOI: 10.1103/physrevb.45.3606] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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8140
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Fang Z, Yang Y, Zhou G. [Isolation and identification of chemical constituents from Hedyotis chrysotricha (Palib.) Merr]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1992; 17:98-100, 127. [PMID: 1418534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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8141
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Yang Y, Rose D, Blake R. On the variety of percepts associated with dichoptic viewing of dissimilar monocular stimuli. Perception 1992; 21:47-62. [PMID: 1528703 DOI: 10.1068/p210047] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Upon dichoptic viewing of dissimilar patterns, several distinct perceptual states may be experienced over time. One state is exclusive monocular dominance, wherein the view of only one eye is seen in its entirety for some period of time. Another state is characterized by a mosaic-like college consisting of portions of the view of each eye. Two other states involve simultaneous perception of both monocular images in their entirety. In one of these states, the two monocular stimuli appear to be superimposed without depth (a phenomenon we shall term 'superimposition'). In the other state, the two monocular stimuli appear to be located at different depth planes (which we shall term 'transparency'). This paper documents the stimulus conditions favoring these various perceptual states. Exclusive monocular dominance occurs most often when the two eyes view dissimilar patterns with the same spatial-frequency content, particularly when both patterns consist of low spatial frequencies. Superimposition also occurs most often when the two eyes view the same spatial frequencies, but predominantly when those spatial frequencies are high. Transparency is favored when the spatial-frequency difference between the eyes is great, particularly when the view of one eye consists of high spatial-frequency information.
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8142
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Yang Y, Chute CG. An application of least squares fit mapping to clinical classification. PROCEEDINGS. SYMPOSIUM ON COMPUTER APPLICATIONS IN MEDICAL CARE 1992:460-4. [PMID: 1482917 PMCID: PMC2248071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This paper describes a unique approach, "Least Square Fit Mapping," to clinical data classification. We use large collections of human-assigned text-to-category matches as training sets to compute the correlations between physicians' terms and canonical concepts. A Linear Least Squares Fit (LLSF) technique is employed to obtain a mapping function which optimally fits the known matches given in a training set and probabilistically captures the unknown matches for arbitrary texts. We tested our method with 16,032 texts from the Mayo Clinic, and judged the results using human-assigned answers. In a test for comparison, the LLSF mapping achieved a precision rate of 89% at 100% recall, outperforming alternative approaches including string matching (36% precision), string matching enhanced by morphological parsing (51% precision), and statistical weighting (61% precision).
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8143
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Chute CG, Yang Y. An evaluation of concept based latent semantic indexing for clinical information retrieval. PROCEEDINGS. SYMPOSIUM ON COMPUTER APPLICATIONS IN MEDICAL CARE 1992:639-43. [PMID: 1482949 PMCID: PMC2247988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Latent Semantic Indexing (LSI) of surgical case report text using ICD-9-CM procedure codes and index terms was evaluated. The precision-recall performance of this two-step matrix retrieval process was compared with the SMART Document retrieval system, surface word matching, and humanly assigned procedure codes. Human coding performed best, two-step LSI did less well than surface matching or SMART. This evaluation suggests that concept-based LSI may be compromised by its two-stage nature and its dependence upon a robust term database linked to main concepts. However, the potential elegance of partial- credit concept matching merits the continued evaluation of LSI for clinical case retrieval.
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8144
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Abstract
In view of the limitations associated with the present tumor markers for prostate cancer, we have examined the potential expression of two further markers, Cathepsin-D and pS2, in human prostate and attempted to link their concentrations with the histopathology of the tissue, the PSA levels and the androgenic status of the gland. Cathepsin-D and pS2 were measured in cytosol fractions obtained from 22 patients with benign prostatic hyperplasia (BPH) and 20 patients with prostate cancer (CaP) employing immunoassays specific for these markers. The concentrations of Cathepsin-D (BPH: mean +/- SEM = 18.50 +/- 1.88 nmol/g protein; CaP = 19.75 +/- 2.49 nmol/g protein) and pS2 (BPH = 1,024.7 +/- 348.06 ng/g protein; CaP = 1,513.88 +/- 268.60 ng/g protein) were not different in the two tissue types, whereas PSA in BPH tissue (1,952.27 +/- 249.93 micrograms/g protein) was significantly higher than the measurements in CaP (583.75 +/- 104.33 micrograms/g protein). However, none of the tumor marker concentrations correlated with the degree of differentiation of the tumors, and we were unable to establish any correlation with the levels of testosterone and dihydrotestosterone in the tissue. In conclusion, although Cathepsin-D and pS2 are expressed in prostate tissue, it is doubtful whether they will have an active role in the management of prostate cancer.
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8145
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Yang Y, Inouye M. Intermolecular complementation between two defective mutant signal-transducing receptors of Escherichia coli. Proc Natl Acad Sci U S A 1991; 88:11057-61. [PMID: 1662380 PMCID: PMC53072 DOI: 10.1073/pnas.88.24.11057] [Citation(s) in RCA: 127] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Taz1 is a hybrid signal-transducing membrane receptor between Tar, an aspartate chemoreceptor, and EnvZ, an osmosensor of Escherichia coli that is able to induce ompC expression by phosphorylating OmpR (a transcriptional activator) in response to aspartate. When the Taz1 His-277, the proposed autophosphorylation site in the cytoplasmic EnvZ domain, was replaced with a valine residue, the mutant Taz1 was unable to induce ompC expression. Similarly, when approximately two-thirds of the EnvZ domain was deleted, Taz1 was nonfunctional. However, when these two defective Taz1 proteins were coexpressed in a cell, ompC was constitutively expressed. Coinciding with this result, two mutant Taz1 molecules were able to intermolecularly complement each other to restore the OmpR kinase activity but not phosphatase activity in vitro. The identical result was also obtained with EnvZ. The present results suggest that the autophosphorylation of Taz1 and EnvZ is an intermolecular phosphorylation reaction, requiring formation of a dimer (or oligomer), and that ligand-dependent ompC expression requires not only kinase but also phosphatase activity.
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8146
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Critelli G, Yang Y, Urbani P, Greco C, Ambrosini M, Sinatra R, Campa PP, Marino B. [The transcatheter ablation of arrhythmias]. CARDIOLOGIA (ROME, ITALY) 1991; 36:469-84. [PMID: 1841803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The introduction of transcatheter ablation techniques has opened a new era of the management of tachyarrhythmias. The rationale of these therapeutic procedures lies in the induction of an irreversible and limited damage to cardiac tissue involved in arrhythmias. In its original form, the technique involves the delivery of high energy DC discharges (fulguration) to the target area through a temporary catheter electrode. A primary drawback of fulguration, when used for ablation of AV node-His bundle, is the induction of a pacemaker-dependent state; the barotraumatic effect that results from high energy impulses constitutes the major limitation in the case of ablation of accessory pathways or arrhythmogenic areas. Recently, the efficiency of the procedure has been substantially improved by the use of low-power, high-frequency alternating current (radiofrequency), that allows to deliver graded amounts of disrupting energy to selected areas while avoiding undesirable biophysical effects to the surrounding tissue. Remarkable results, with a success rate close to 100%, are reported with radiofrequency ablation of AV node reentry tachycardia, as well as reciprocating tachycardia associated with the preexcitation syndrome, so that this technique can be considered the procedure of choice for both categories of patients. Catheter modification of AV conduction provides a therapeutic tool for treating atrial tachyarrhythmias with rapid ventricular responses. In such cases, however, the risk of AV block with the need for pacemaker implantation must be taken into account. Results of catheter ablation of ventricular tachycardia have been inconstant and generally disappointing, except for ventricular tachycardias due to reentry in the His-Purkinje system, for which a high success rate is reported. Experience with radiofrequency ablation in ventricular tachycardia is very limited, but localization of a critical segment of reentry could improve the efficiency of this technique.
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8147
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Wells WW, Rocque PA, Xu DP, Yang Y, Deits TL. Interactions of platinum complexes with thioltransferase(glutaredoxin), in vitro. Biochem Biophys Res Commun 1991; 180:735-41. [PMID: 1953747 DOI: 10.1016/s0006-291x(05)81127-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Under anaerobic conditions, recombinant pig liver thioltransferase (glutaredoxin)(TT, GRX) (EC 1.8.4.1) was strongly inhibited by cis and carbo-platin and somewhat less sensitive to trans-platin, in vitro. By extrapolation to total inhibition, the ratio of platinum drug/thioltransferase was approximately 1.0 for cis and carbo-platin, but greater than 1.0 for trans-platin. When thioltransferase was not reduced, inhibition by preincubation with the platinum complexes required molar excesses of 1,300 and 675 to one for cis-platin and trans-platin, respectively or 400-500 microM for 50% inhibition. The inhibition of thioltransferase at high drug concentrations in the presence of oxygen was associated with cross-linking of monomers into dimers within 5 min and, in the case of cis-platin treatment, to trimers in 20 min incubation.
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8148
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Yang Y, Huang L, Liu Q, Kang B. Structure of a binuclear disulfido–vanadium complex, [V2(μ-η2-S2)2(Et2NCS2)4]. Acta Crystallogr C 1991. [DOI: 10.1107/s0108270191004912] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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8149
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Hunt JS, Yang Y, Wheaton D, Kunz HW, Gill TJ. Analysis of the expression and immunostimulatory capacity of class I major histocompatibility antigens on rat trophoblast cell lines. Am J Reprod Immunol 1991; 26:129-35. [PMID: 1839605 DOI: 10.1111/j.1600-0897.1991.tb00710.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In rat strains expressing the a and other major histocompatibility complex (MHC) haplotypes, subpopulations of placental trophoblast cells synthesize the nonclassical class I Pa antigen in preference to the classical RT1.Aa antigen. In this study, a rat trophoblast cell line, R8RP.3, which was derived from midgestation placentas of PVG.R8 (RT1.Aa) rats, was shown to express class I antigens similarly to those of trophoblast cells in situ. Both unstimulated and IFN-gamma-exposed metabolically labeled R8RP.3 cells synthesized more Pa than RT1.Aa antigen. The reverse was true for labeled spleen cells from PVG.R8 rats. The R8RP.3 cells failed to stimulate allogeneic lymphocyte proliferation even when high levels of both classical and nonclassical class I MHC antigens were expressed on their membranes after incubation with IFN-gamma. These experiments thus supply the first evidence that the inductive phase of the immune response is not promoted by trophoblast cell class I MHC antigens, which could explain the failure of mothers to mount immune responses to class I MHC positive trophoblast cells.
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8150
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Xu PZ, Yang Y, Wang J, Li JA. Endobronchial metastatic carcinoma in three cases. Chin Med J (Engl) 1991; 104:874-7. [PMID: 1661227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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