501
|
Zucchi R, Limbruno U, Ronca-Testoni S, Yu G, Galbani P, Ronca G, Mariani M. Effects of verapamil, gallopamil, diltiazem and nifedipine on sarcoplasmic reticulum function in rat heart. CARDIOSCIENCE 1992; 3:167-72. [PMID: 1330045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We investigated the effect of the calcium antagonists verapamil, gallopamil, diltiazem and nifedipine on cardiac sarcoplasmic reticulum function. In a cell-free homogenate from rat hearts, oxalate-supported Ca uptake was stimulated by verapamil, gallopamil and diltiazem at concentrations in the order of 10 nM to 100 nM, while higher concentrations were ineffective. Nifedipine was also ineffective. Peak stimulation of Ca uptake averaged 15-20% of control. Ca uptake is the difference between active Ca transport by Ca-ATPase and passive efflux through sarcoplasmic reticulum channels. In the presence of 300 microM ryanodine, which blocks sarcoplasmic reticulum channels, Ca uptake increased by 50%, but no further stimulation was produced by the addition of any calcium antagonist, at concentrations ranging from 1 nM to 100 microM. In a fraction enriched in sarcoplasmic reticulum, no drug affected the activity of Ca-ATPase at concentrations able to stimulate Ca uptake. We conclude that low concentrations of verapamil, gallopamil and diltiazem reduce Ca efflux through the Ca channels of the sarcoplasmic reticulum. Such an action might contribute to the clinical effect of these drugs.
Collapse
|
502
|
Huang ZQ, Zhou NX, Liu YX, Li WH, Yu G. Surgical treatment of hilar bile duct carcinoma. Clinical and pathological studies. Chin Med J (Engl) 1992; 105:635-40. [PMID: 1458965] [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
Resection of the extrahepatic bile tract for hilar bile duct carcinoma was performed at the PLA General Hospital, with a resectability rate of 62% (31/50) and no operative mortality. Hepatic lobectomy was performed at the same time in 16 cases (51.6%). Reoperative resections were successfully done in 5 cases; 4 cases are still living 1-4 years after the second operation. The cause of late death was mainly biliary infection due to local recurrence and bile duct obstruction. The median survival period was 15 months. 32 cases were studied pathologically, of which 27 were resected surgical specimens and 5 autopsies. The tumors were histologically classified into 4 types: papillary adenocarcinoma (6 cases); well differentiated adenocarcinoma (21); poorly differentiated adenocarcinoma (3); and simple carcinoma (2). The importance of early diagnosis of hilar bile duct carcinoma at its subclinical stage before appearance of clinical jaundice is stressed.
Collapse
|
503
|
Yu G. Trapping of point defects in alloys. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:642-651. [PMID: 10003248 DOI: 10.1103/physrevb.46.642] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
504
|
Zucchi R, Ronca-Testoni S, Galbani P, Yu G, Mariani M, Ronca G. Cardiac A2 adenosine receptors--influence of ischaemia. Cardiovasc Res 1992; 26:549-54. [PMID: 1446324 DOI: 10.1093/cvr/26.5.549] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
OBJECTIVE The aim was to detect cardiac A2 adenosine receptors through radioligand binding, and to assess the effect of ischaemia on these receptors. METHODS Isolated working rat hearts were subjected either to aerobic perfusion or to global ischaemia. A membrane fraction was prepared from ventricular tissue, and 3H-5'-N-ethylcarboxamide adenosine (NECA) binding was determined in the presence of N6-cyclopentyl adenosine (CPA). A2 binding was calculated as the fraction of NECA binding displaced by 100 microM CPA but not displaced by 50 nM CPA. RESULTS Analysis of A2 NECA binding according to single binding site model yielded Kd = 22.0 nM, Bmax = 34.0 fmol.mg-1 in control hearts; Kd = 49.7 nM, Bmax = 44.3 fmol.mg-1 in hearts subjected to 30 min ischaemia (p < 0.05 for difference in Kd). In the control group a two site model provided a significantly (p < 0.05) better fit (Kd = 5.6 and 183.7 nM, Bmax = 9.5 and 64.4 fmol.mg-1 for the high and low affinity sites respectively). The high affinity component of A2 NECA binding disappeared in the presence of the GTP analogue guanyl-5'-yl imidodiphosphate, suggesting the existence of multiple coupling states of the receptor. In the ischaemic group no significant improvement in data fitting was obtained with the two site model. CONCLUSIONS The results provide evidence of the existence of cardiac A2 adenosine receptors. Ischaemia modifies receptor properties and appears to affect chiefly the high affinity component of A2 binding, possibly by preventing receptor interaction with membrane G proteins.
Collapse
|
505
|
Yu G, Li WH. [Pathological study on 10 cases of inflammatory pseudotumour of the liver]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1992; 21:109-10. [PMID: 1499072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Histopathological changes of 10 cases of resected inflammatory pseudotumour of liver were observed. These cases were considered to be the primary liver carcinomas or malignant tumours clinically. Morphologically, the inflammatory pseudotumour of liver exhibited varied histological features, including plasma cell granuloma, xanthogranuloma, fibrous proliferation, endophlebitis, necrosis etc. All these cases showed the characteristics of an inflammatory proliferative mass. The causes and the diagnosis criteria of inflammatory pseudotumours of liver were briefly discussed.
Collapse
|
506
|
Limbruno U, Zucchi R, Ronca-Testoni S, Galbani P, Yu G, Ronca G, Mariani M. [Effects of oxygen free radicals on the function of the cardiac sarcoplasmic reticulum]. CARDIOLOGIA (ROME, ITALY) 1992; 37:215-20. [PMID: 1324120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Peroxidative stress, exerted by oxygen free radicals, seems to be an important mechanism of the ischemia-reperfusion myocardial damage. In the present study we evaluated the modifications of sarcoplasmic reticulum function subjected to peroxidation by ferric ions. A subcellular fraction enriched in sarcoplasmic reticulum was obtained from rabbit hearts by homogenization and differential centrifugations. Sarcoplasmic reticulum vesicles were peroxidated through incubation for 5 min at 37 degrees C in presence of ferric cloride (FeCl3) ranging in concentration between 0.3 and 0.9 mM. Peroxidation of sarcoplasmic reticulum vesicles determined a dose-dependent reduction of Ca-uptake (39.2 +/- 10.3, 36.5 +/- 9.9, 28.9 +/- 8.4 and 18.8 +/- 8.2 nmol/min/mg in presence of 0, 0.3, 0.6 e 0.9 mM FeCl3; NS, p less than 0.05 and less than 0.01, respectively) which was paralleled by an increase in the production of malondialdehyde, an index of lipid peroxidation (1.0 +/- 1.0, 7.0 +/- 3.2, 14.1 +/- 3.9 and 27.0 +/- 4.7 nmol/mg in presence of 0, 0.3, 0.6 e 0.9 mM FeCl3; p less than 0.05, less than 0.01 and less than 0.01, respectively). Depression of Ca-uptake was not accounted for by modifications of Ca-ATPase activity or membrane aspecific permeability to Ca++ ions, since these parameters were not affected by exposure to 0.3-0.9 mM FeCl3. On the contrary, the responsiveness of Ca-release channels to the specific inhibitor ryanodine was greatly altered, even at lower FeCl3 concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
507
|
Yu G, Lee CH, Heeger AJ, Herron N, McCarron EM, Cong L, Spalding GC, Nordman CA, Goldman AM. Phase separation of photogenerated carriers and photoinduced superconductivity in high-Tc materials. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:4964-4977. [PMID: 10002139 DOI: 10.1103/physrevb.45.4964] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
508
|
Chan WC, Gu LB, Masih A, Nicholson J, Vogler WR, Yu G, Nasr S. Large granular lymphocyte proliferation with the natural killer-cell phenotype. Am J Clin Pathol 1992; 97:353-8. [PMID: 1543158 DOI: 10.1093/ajcp/97.3.353] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Lymphoproliferated disorders involving large granular lymphocytes (LGL) can be divided into a common T-cell subset (CD3+, CD8+) and a rarer natural killer (NK)-cell subset (CD2+, CD3-). The immunophenotype, clinical pathologic features, and cytogenetic and molecular genetic analyses are reported for seven patients with NK-cell-LGL proliferation. The typical immunophenotype was CD2+, CD3-, CD4-, CD11b+, and CD16+ or CD56+. A low but variable percentage of cells were CD8+ or CD57+. Unusual phenotypes with CD2- (1 of 7), CD11b- (1 of 7), or CD16-/CD56- (1 of 7) cells were seen. Strong NK-cell activity was observed in all cases, indicating that none of the NK-cell markers (CD11b, CD16, CD56, CD57) is essential for NK-cell activity. One patient died shortly after diagnosis from coexistent refractory multiple myeloma and another patient died within 1 month from the LGL proliferation. The other patients had been followed for 12 to 70 months, with a median follow-up period of 38 months. There was no progression of their LGL proliferation. Lymphocyte counts varied from 3.3 x 10(3)/microL to 58.4 x 10(3)/microL at the time of diagnosis. Unexplained anemia and neutropenia were observed in one patient. Cytogenetic abnormalities were detected in two of four patients studied with t(6;12) in one and der(5), der(6), and der(11) in the other. The approximately T gamma and T beta genes were in the germline configuration and Epstein-Barr virus DNA was undetectable in five of five patients studied. Natural killer-cell LGL proliferations were morphologically indistinguishable from T-cell LGL proliferations. However, the two were immunophenotypically and genotypically distinct and NK-cell activity was consistently observed in the former. Most of the NK-cell proliferations also were chronic indolent disorders and the incidence of associated cytopenias seemed to be lower than T-cell LGL proliferations.
Collapse
|
509
|
Yu G, Felsted RL. Effect of myristoylation on p27 nef subcellular distribution and suppression of HIV-LTR transcription. Virology 1992; 187:46-55. [PMID: 1736544 DOI: 10.1016/0042-6822(92)90293-x] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effect of myristoylation on p27nef subcellular distribution and suppression of HIV-1 transcription was examined by transfecting COS-7 cells with plasmids expressing either myristoylated (pSVnef) or nonmyristolyated p27nef (pSVnefala2). Similar levels of myristoylated and nonmyristoylated p27nef were expressed with only the product of the pSVnef plasmid being myristoylated. Immuno-histochemical microscopy and radioimmunoprecipitation revealed myristolyated p27nef only in the membrane fraction while nonmyristolyated p27nef was found distributed between the nucleus and the cytosol fractions. The effect of myristoylation on p27nef suppression of HIV LTR controlled transcription was examined in transient transfected COS cells and in CEM human T-cell clones consituitively expressing either myristolyated or nonmyristolyated p27nef by cotransfecting with a chloramphenicol acetyltransferase (CAT) plasmid under control of the HIV-1 LTR. In both systems, myristoylated p27nef exhibited a 13- to 18-fold inhibition of basal CAT activity while the nonmyristolyated mutant and the same plasmid carrying the nef gene in a reverse orientation inhibited CAT activity one- to two-fold. These results confirm the cytoplasmic membrane localization of p27nef and establish that its subcellular targeting is dependent on covalently attached myristate. The data also provide further evidence that p27nef acts as a transcriptional suppressor and establishes for the first time that myristolyation is required for the full manifestation of this effect.
Collapse
|
510
|
Yu G, Lee CH, Heeger AJ, Herron N, McCarron EM. Transient photoinduced conductivity in single crystals of YBa2Cu3O6.3: "Photodoping" to the metallic state. PHYSICAL REVIEW LETTERS 1991; 67:2581-2584. [PMID: 10044462 DOI: 10.1103/physrevlett.67.2581] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
511
|
Yu G, Maskray V, Jackson SH, Swift CG, Tiplady B. A comparison of the central nervous system effects of caffeine and theophylline in elderly subjects. Br J Clin Pharmacol 1991; 32:341-5. [PMID: 1777371 PMCID: PMC1368528 DOI: 10.1111/j.1365-2125.1991.tb03909.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
1. The effects of oral administration of 250 mg caffeine or theophylline and placebo on subjective ratings and psychological test performance were studied in a double-blind crossover experiment in 20 healthy elderly subjects. 2. Performance on the continuous attention task showed a significant improvement compared with placebo with both active treatments. Performance with caffeine was significantly better than with theophylline. Mean error index scores (normalised AUCs) were: placebo--0.130; caffeine--0.083; theophylline--0.093. No other objective measure shows significant treatment effects. 3. Subjective ratings showed that subjects felt significantly more alert on caffeine than on either theophylline or placebo. Subjects also rated themselves as more energetic and interested on caffeine than on placebo. 4. Plasma concentrations of caffeine were lower than those of theophylline (mean 5.76 and 8.72 mg l-1 respectively at 2 h post-drug. 5. These results suggest that caffeine is a more potent CNS stimulant than theophylline.
Collapse
|
512
|
Yu G. [Analysis of the curative effect of partially accommodative esotropia in children]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1991; 27:282-4. [PMID: 1815921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Partially accommodative esotropia in children is due to accommodative factor in addition to anatomical factor. The former is corrected with spectacles, whereas the latter must be surgically treated. The authors handled 75 such cases by first prescribing spectacles for full correction of hyperopia, and surgical operations were performed to the residual esotropia after wearing the spectacles for 6 months. Patients surgically under-corrected were advised to wear over-correction spectacles, and patients surgically over-corrected to wear under-correction spectacles. Skiascopic examinations were done every 6 months; the physiological hyperopia decreased year by year, and the strength of hyperopic spectacles was decreased accordingly.
Collapse
|
513
|
Williams AJ, Yu G, Santiago S, Stein M. Screening for sleep apnea using pulse oximetry and a clinical score. Chest 1991; 100:631-5. [PMID: 1889245 DOI: 10.1378/chest.100.3.631] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Confirmation of the diagnosis of OSA currently requires overnight polysomnography. This study evaluates the usefulness of pulse oximetry together with a clinical score in identifying OSA. Forty patients were assigned a clinical score based on the presence or absence of loud snoring, observations of interrupted breathing during sleep, hypersomnolence, obesity and essential hypertension. Each underwent a night of domiciliary pulse oximetry followed by nocturnal polysomnography. Significant OSA was confirmed in 26. All 15 patients with positive pulse oximetry tracings had significant OSA (apnea index greater than or equal to 10). Five of eight with negative tracings were also shown to have significant OSA along with six of the seven patients with inadequate or indeterminate tracings. Clinical scores were significantly different for those with and without OSA. This study confirms the usefulness of nocturnal pulse oximetry in establishing the diagnosis of OSA and highlights the value of a clinical score in improving its sensitivity as a screening tool.
Collapse
|
514
|
Borellini F, He YF, Aquino A, Yu G, Josephs SF, Glazer RI. Increased DNA binding and transcriptional activity associated with transcription factor Sp1 in K562 cells transfected with the myeloid-specific c-fes tyrosine kinase gene. J Biol Chem 1991; 266:15850-4. [PMID: 1874737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Myeloblast cell line K562, when stably transfected with the human genomic c-fes sequence encoding a proto-oncogene tyrosine-protein kinase, acquires the characteristics of more mature granulocytic cells (WS-1 cells) and the ability to undergo differentiation (Yu, G., Smithgall, T. E., and Glazer, R. I. (1989) J. Biol. Chem. 264, 10276-10281). To explore the role of transcription factors in the differentiation process, WS-1 cells were analyzed for the presence of DNA-binding proteins capable of interacting with the 5'-long terminal repeat (LTR) region of human immunodeficiency virus (HIV)-1, that contains the binding sequences for transcription factors Sp1 and NFKB. Southwestern blotting and mobility shift assays revealed the presence of Sp1 in K562 and WS-1 cells. The DNA-binding activity of Sp1 was significantly greater in WS-1 cells than in K562 cells, despite the detection by immuno-blotting of equivalent quantities and degrees of heterogeneity of Sp1 in both cell lines. DNA footprinting of the HIV-1 5'-LTR demonstrated that two of the three Sp1-binding sites and both NFKB binding sequences were protected by nuclear extracts from WS-1 cells, while no protection was afforded by nuclear extracts from K562 cells. Analysis of transcription in vitro by primer extension revealed enhanced initiation of transcription from the HIV-1 5'-LTR by nuclear extracts from WS-1 cells, but not from K562 cells. These data indicate that the response evoked by the c-fes tyrosine-protein kinase leads to enhanced DNA binding activity of Sp1 and NFKB, that results in the activation of transcription from the HIV-1 5'-LTR.
Collapse
|
515
|
Borellini F, He Y, Aquino A, Yu G, Josephs S, Glazer R. Increased DNA binding and transcriptional activity associated with transcription factor Sp1 in K562 cells transfected with the myeloid-specific c-fes tyrosine kinase gene. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)98486-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
516
|
Yu G, Ahmad S, Aquino A, Fairchild CR, Trepel JB, Ohno S, Suzuki K, Tsuruo T, Cowan KH, Glazer RI. Transfection with protein kinase C alpha confers increased multidrug resistance to MCF-7 cells expressing P-glycoprotein. Cancer Commun (Lond) 1991; 3:181-9. [PMID: 1675575 DOI: 10.3727/095535491820873263] [Citation(s) in RCA: 129] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Cross-resistance to anticancer drugs, termed multidrug resistance (mdr), has been functionally associated with the expression of a plasma membrane energy-dependent efflux pump, termed P-glycoprotein, the product of the mdr1 gene. When MCF-7 breast carcinoma cells were transfected with the human mdr1 gene (BC-19 cells), they expressed levels of P-glycoprotein equivalent to those of cells selected for resistance to doxorubicin (MCF-7/ADR) but exhibited 10- to 50-fold less resistance to doxorubicin and vinblastine. We have now demonstrated that when BC-19 cells were stably transfected with protein kinase C alpha (PKC alpha), resistance to doxorubicin and vinblastine was increased; wild-type MCF-7 cells transfected with PKC alpha did not exhibit any change in drug resistance. Increased resistance in PKC alpha-transfected BC-19 cells was associated with enhanced PKC activity and phosphorylation of P-glycoprotein and decreased drug accumulation. The PKC activator, phorbol dibutyrate, further increased resistance to doxorubicin and stimulated P-glycoprotein phosphorylation. These results demonstrate that transfection of P-glycoprotein-expressing cells with PKC resulted in increased mdr and that PKC may have served as an important modulator of this process.
Collapse
|
517
|
Lanier LL, Yu G, Phillips JH. Analysis of Fc gamma RIII (CD16) membrane expression and association with CD3 zeta and Fc epsilon RI-gamma by site-directed mutation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1991; 146:1571-6. [PMID: 1825220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Two genes encode Fc gamma RIII (CD16), a low affinity FcR for IgG. CD16-I is expressed as a phosphatidylinositol glycan-anchored membrane glycoprotein on neutrophils, whereas CD16-II is a transmembrane-linked glycoprotein on NK cells. Membrane anchoring is determined by codon 203. Site-directed mutation of codon 203 and transient expression of these cDNA in COS-7 cells indicated that Phe, Ile, Leu, and Val permit transmembrane expression, whereas Ser, Thr, Tyr, Asn, Gly, Ala, Asp and Lys enable phosphatidylinositol-glycan attachment. Thus, the involvement of amino acid 203 in membrane anchoring cannot be explained simply on the basis of size, charge, or polarity of the amino acid side groups at this site. Efficient expression of CD16-II in COS-7 cells requires co-transfection with either CD3 zeta or Fc epsilon RI-gamma. Truncation of the cytoplasmic segment of CD16 failed to affect association with CD3 zeta. CD3 zeta and Fc epsilon RI-gamma with truncated cytoplasmic segments were also able to facilitate membrane expression of CD16-II, implicating the transmembrane segments as the interaction site between CD16-II and CD3 zeta or Fc epsilon RI-gamma. Prior studies have suggested that the acidic residue in the CD3 zeta transmembrane segment may be important for the association of CD3 zeta complexes. Although site-directed mutation of CD3 zeta-Asp36 to Glu, Leu, or Val retained the ability to permit membrane expression of CD16-II, quantitatively the wild-type CD3 zeta-Asp36 provided optimal levels of expression, consistent with conservation of this amino acid in mouse and human CD3 zeta.
Collapse
MESH Headings
- Antigens, CD/biosynthesis
- Antigens, Differentiation/biosynthesis
- Antigens, Differentiation/genetics
- Base Sequence
- Cells, Cultured
- Humans
- Membrane Glycoproteins/physiology
- Membrane Proteins
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Receptors, Antigen, T-Cell/physiology
- Receptors, Fc/biosynthesis
- Receptors, Fc/genetics
- Receptors, IgG
- Structure-Activity Relationship
- Transfection
Collapse
|
518
|
Lanier LL, Yu G, Phillips JH. Analysis of Fc gamma RIII (CD16) membrane expression and association with CD3 zeta and Fc epsilon RI-gamma by site-directed mutation. THE JOURNAL OF IMMUNOLOGY 1991. [DOI: 10.4049/jimmunol.146.5.1571] [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
Two genes encode Fc gamma RIII (CD16), a low affinity FcR for IgG. CD16-I is expressed as a phosphatidylinositol glycan-anchored membrane glycoprotein on neutrophils, whereas CD16-II is a transmembrane-linked glycoprotein on NK cells. Membrane anchoring is determined by codon 203. Site-directed mutation of codon 203 and transient expression of these cDNA in COS-7 cells indicated that Phe, Ile, Leu, and Val permit transmembrane expression, whereas Ser, Thr, Tyr, Asn, Gly, Ala, Asp and Lys enable phosphatidylinositol-glycan attachment. Thus, the involvement of amino acid 203 in membrane anchoring cannot be explained simply on the basis of size, charge, or polarity of the amino acid side groups at this site. Efficient expression of CD16-II in COS-7 cells requires co-transfection with either CD3 zeta or Fc epsilon RI-gamma. Truncation of the cytoplasmic segment of CD16 failed to affect association with CD3 zeta. CD3 zeta and Fc epsilon RI-gamma with truncated cytoplasmic segments were also able to facilitate membrane expression of CD16-II, implicating the transmembrane segments as the interaction site between CD16-II and CD3 zeta or Fc epsilon RI-gamma. Prior studies have suggested that the acidic residue in the CD3 zeta transmembrane segment may be important for the association of CD3 zeta complexes. Although site-directed mutation of CD3 zeta-Asp36 to Glu, Leu, or Val retained the ability to permit membrane expression of CD16-II, quantitatively the wild-type CD3 zeta-Asp36 provided optimal levels of expression, consistent with conservation of this amino acid in mouse and human CD3 zeta.
Collapse
|
519
|
Yu G. [Research on the improvement of dosage forms of prescriptions in Chinese traditional medicine]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1991; 16:182-6. [PMID: 1883506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
520
|
Roenigk HH, Kuzel TM, Skoutelis AP, Springer E, Yu G, Caro W, Gilyon K, Variakojis D, Kaul K, Bunn PA. Photochemotherapy alone or combined with interferon alpha-2a in the treatment of cutaneous T-cell lymphoma. J Invest Dermatol 1990; 95:198S-205S. [PMID: 2258636 DOI: 10.1111/1523-1747.ep12875523] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Eighty-two patients with either mycosis fungoides (MF) or parapsoriasis en plaques were treated with psoralens ultraviolet A light (PUVA). Clinical and histologic parameters were followed for a period from 6 months to 10 years. Complete clinical clearing of lesions was observed in 51 patients (62%) and most of them were in limited-plaque MF group or parapsoriasis en plaque. The mean total dose of PUVA for complete clearing was less for early MF. Thirty-one patients (38%) relapsed and responded to additional PUVA. Patients in early stages of the disease remained clear for up to 68 months after the first course of PUVA. Post-treatment skin biopsies with early MF showed histologic clearing. A new combination therapy for MF is presented in 15 patients. Recombinant interferon alpha-2a (Roferon-A), administered intramuscularly combined with PUVA were tested in a phase I trial. Interferon doses were from 6-30 million units three times weekly. Disease stages ranged from I-B to IV-B. Complete responses were obtained in 12 of 15 patients, and partial responses seen in 2 of 15 patients, for an overall response rate of 93%. The median duration of response exceeded 23 months (range, 3 to 25 months). All responding patients have been maintained on therapy. The dose-limiting toxicities were constitutional symptoms such as fevers and malaise (93.3%), leukopenias (40.0%), mental status changes consisting of depression and confusion (33.3%), and photosensitivity (26.6%). Interferon plus PUVA appear to be highly effective regimens for the treatment of patients with cutaneous T-cell lymphomas.
Collapse
|
521
|
Zhou Y, Ma Z, Li Y, Pan L, Xu G, Xu L, Yu G, Li P. [Investigation on resources of the Chinese drug beimu in Gansu Province]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1990; 15:515-6, 575. [PMID: 2092708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Based on a resources investigation and taxonomic research on the medicinal plants of Fritillaria from Gansu Province. Nine species one variety and one cultivation variety have been reported. Records and distribution of the species, together with a key for the species and a key for the powdered drug have been furnished as well.
Collapse
|
522
|
Yu G, Phillips SD, Tomozawa H, Heeger AJ. Subnanosecond transient photoconductivity in poly(3-hexylthiophene). PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 42:3004-3010. [PMID: 9995792 DOI: 10.1103/physrevb.42.3004] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
523
|
Yu G, Chen J, Wang J, Hou J. New progress in the four diagnostic methods of cancer. J TRADIT CHIN MED 1990; 10:152-5. [PMID: 2202875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
524
|
Zeng Z, Shen H, Huang M, Xu H, Zeng R, Zhou Y, Yu G, Huang C. Measurement of the refractive index and thermal refractive index coefficients of Nd:YAP crystal. APPLIED OPTICS 1990; 29:1281-1286. [PMID: 20562993 DOI: 10.1364/ao.29.001281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The principal refractive indices of yttrium aluminate crystal doping with 1-wt.% neodymium (Nd:YAP) have been measured by a minimum deviation method for the wavelengths 0.5398, 0.6328, and 1.0795 microm in the temperature range of 289-435 K. The thermal refractive index coefficients have been obtained at these wavelengths, and they are all positive and slightly decrease with increased wavelength. The constants of the single term Sellmeier equation are also given for the 273-420 K temperature range. These constants are in linear relationship with temperature in the 4 x 10(-3) error range.
Collapse
|
525
|
Yu G, Ye D. [Optimal potassium concentration in cardioplegic solutions]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 1990; 18:42-6, 62. [PMID: 2397698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A model of perfused cardiac papillary muscle from guinea pig was set up in our lab. The procaine-free St. Thomas' Hospital solution was used as the basic cardioplegic solution. The potassium concentration of the solution was designed by optimization (14.6, 22.8, 28.5, 32.6, 57.8 mmol/L). The papillary muscle was undergone anoxic arrest for 60 min in 32 degrees C. The effect of myocardium preservation was assessed with cardiac action potential, contractility and quantitative analysis of ultrastructure. We concluded that; (1) in this research the proper potassium concentration is at the range of 20.7-26.0 mmol/L and the optimal one is 22.8 mmol/L; (2) despite any deviation from the range, phases II and III of the action potential changes first. [K+] greater than or equal to 32.6 mmol/L slows conductivity, weakens contractility and damages the subcellular structure severely; (3) if [K+] is 57.8 mmol/L, anoxic arrest for 60 minutes in 32 degrees C damages of both structure and function of myocardium is irreversible; (4) following the hyperkalemic cardioplegia, there is a secondary change of cardiac action potential in reperfusion period, which shows longer phase II and shorter phase III, smaller Vmax and APA; (5) reperfusion arrhythmia after anoxic hyperkalemic asystole is likely caused by all kinds of conductive disorders resulting from the secondary changes of action potential; (6) arrest time, AT (Y, s) has the negative relativity to the potassium concentration (X, mmol/L) of cardioplegic solution, which can regress to curve 1/Y = 0.10-1.38/X(14.6 less than or equal to X less than or equal to 57.8). The minimum potassium concentration which can guarantee AT within 30 seconds is 20.7 mmol/L.
Collapse
|
526
|
Kehoe RF, Zheutlin TA, Dunnington CS, Mattioni TA, Yu G, Spangenberg RB. Safety and efficacy of sotalol in patients with drug-refractory sustained ventricular tachyarrhythmias. Am J Cardiol 1990; 65:58A-64A; discussion 65A-66A. [PMID: 2294689 DOI: 10.1016/0002-9149(90)90204-e] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The safety and efficacy of oral sotalol, an investigational beta-adrenergic blocker with class III antiarrhythmic drug properties, were examined in a multicenter study in 236 patients with sustained ventricular tachyarrhythmias. In 104 patients, the index arrhythmia was a cardiac arrest, and all patients had undergone at least 3 previous unsuccessful antiarrhythmic trials (mean = 5 per patient). In the 106 patients assessed by programmed electrical stimulation, sotalol completely suppressed induction of ventricular tachycardia (VT) in 33 (31%) and rendered VT slower (greater than 100 ms prolongation of cycle length) or more difficult to induce in 29 (27%). Using continuous 24-hour ambulatory monitoring methods, sotalol complete- and partial-response rates were 51 and 12%, respectively. Of the 236 acute-phase patients, 151 were discharged receiving long-term sotalol therapy. The median sotalol dose was 480 mg/day. At a mean follow-up of 346 +/- 92 days, 27 patients (18%) had recurrence of sustained arrhythmia; 9, sudden death; 11, sustained VT; 5, automatic defibrillator discharge; and 2, syncope. Adverse effects forced discontinuation of therapy in 10 patients (7%): 6 secondary to symptomatic bradyarrhythmia, 2 due to refractory heart failure, 1 due to torsades de pointes, and 1 from bronchospasm. Life-table analysis of sotalol's overall long-term efficacy at 6, 12 and 18 months were 80, 76 and 72%, respectively. Although mean follow-up was short (less than 1 year), neither acute-phase programmed stimulation nor 24-hour ambulatory monitoring responses were significantly predictive of subsequent arrhythmic outcome. Proarrhythmia was documented in 18 patients (7%), 17 during the acute phase and 1 during long-term follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
527
|
Lanier LL, Cwirla S, Yu G, Testi R, Phillips JH. Membrane anchoring of a human IgG Fc receptor (CD16) determined by a single amino acid. Science 1989; 246:1611-3. [PMID: 2531919 DOI: 10.1126/science.2531919] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
CD16 is a low-affinity immunoglobulin G (IgG) Fc receptor that is expressed on natural killer (NK) cells, granulocytes, activated macrophages, and some T lymphocytes. Two similar genes, CD16-I and CD16-II, encode membrane glycoproteins that are anchored by phosphatidylinositol (PI)-glycan and transmembrane polypeptides, respectively. The primary structural requirements for PI-linkage were examined by constructing a series of hybrid cDNA molecules. Although both cDNA's have an identical COOH-terminal hydrophobic segment, CD16-I has Ser203 whereas CD16-II has Phe203. Conversion of Phe to Ser in CD16-II permits expression of a PI-glycan-anchored glycoprotein, whereas conversion of Ser to Phe in CD16-I prevents PI-glycan linkage.
Collapse
|
528
|
Lanier LL, Yu G, Phillips JH. Co-association of CD3 zeta with a receptor (CD16) for IgG Fc on human natural killer cells. Nature 1989; 342:803-5. [PMID: 2532305 DOI: 10.1038/342803a0] [Citation(s) in RCA: 301] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Natural killer (NK) cells are a subset of lymphocytes that mediate major histocompatibility complex (MHC)-nonrestricted cytotoxicity against tumours and virus-infected cells and secrete numerous cytokines on activation. NK cells are distinct from mature T lymphocytes, because they do not rearrange or productively transcribe T-cell receptor alpha-, beta-, gamma- or delta-chain genes and do not express the CD3 gamma- or delta-subunits. But recent studies indicate that NK cells do express CD3 zeta, co-associated with other membrane proteins. Here we report that CD16, the receptor for the Fc (constant) region of IgG, specifically associates with the CD3 zeta homodimer on the membrane of human NK cells, and that co-transfection with CD3 zeta complementary DNA permits expression of a transmembrane-linked CD16 complex on COS-7 cells. These findings indicate that CD3 zeta can co-associate with membrane receptors of diverse cell types and function as a common structure for signal transduction.
Collapse
|
529
|
Phillips SD, Worland R, Yu G, Hagler T, Freedman R, Cao Y, Yoon V, Chiang J, Walker WC, Heeger AJ. Electroabsorption of polyacetylene. PHYSICAL REVIEW. B, CONDENSED MATTER 1989; 40:9751-9759. [PMID: 9991496 DOI: 10.1103/physrevb.40.9751] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
530
|
Yu G. [The surgical treatment of intermittent exotropia]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1989; 25:279-81. [PMID: 2633904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
77 cases of surgically treated intermittent exotropia were followed up for analysis with regard to the relation between the age of operation and curative effect, the age and post-operative restoration of homologous retinal correspondence, and the effect of over-correction on final orthophoria. The authors were of the opinion that the earliest surgical intervention was conducive to recovery of Grade III visual function and restoration of homologous retinal correspondence, and slight over-correction was significant for final orthophoria. They recommended that the earliest surgical intervention be accorded patients with intermittent exotropia of 20 delta and over, instead of purposeless waiting and observation.
Collapse
|
531
|
Yu G, Smithgall TE, Glazer RI. K562 leukemia cells transfected with the human c-fes gene acquire the ability to undergo myeloid differentiation. J Biol Chem 1989; 264:10276-81. [PMID: 2656706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Expression of the proto-oncogene p93c-fes and its associated tyrosine kinase activity is marked in mature granulocytes, monocytes, differentiated HL-60 leukemia cells, and leukemia cell lines KG-1, THP-1, HEL, and U-937, which can be induced to differentiate along the granulocyte/monocyte pathway. Conversely, p93-c-fes expression is absent in the K562 cell line, which is resistant to myeloid differentiation. Upon transfection and clonal selection of K562 cells using a mammalian expression vector containing the 13-kilobase pair c-fes gene, c-fes mRNA was transcribed and p93-c-fes tyrosine activity kinase was expressed. Clones expressing c-fes underwent myeloid differentiation as assessed by the appearance of phagocytic activity, Fc receptors, nitro blue tetrazolium reduction, Mac-1 immunofluorescence, and lysozyme production. These results indicate that the expression of the c-fes protooncogene and its associated tyrosine kinase activity plays a major role in the initiation of myeloid differentiation.
Collapse
|
532
|
Yu G, Smithgall TE, Glazer RI. K562 leukemia cells transfected with the human c-fes gene acquire the ability to undergo myeloid differentiation. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)81796-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
533
|
Phillips SD, Yu G, Cao Y, Heeger AJ. Spectroscopy and transient photoconductivity of partially crystalline polyaniline. PHYSICAL REVIEW. B, CONDENSED MATTER 1989; 39:10702-10707. [PMID: 9947879 DOI: 10.1103/physrevb.39.10702] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
534
|
Chen SX, Zhang SH, Zhang XZ, Zheng XJ, Yu G, Huang MX, Zheng DS. A clinical investigation with Holter's monitoring of the antiarrhythmic effect of adonisidum. J TRADIT CHIN MED 1989; 9:35-9. [PMID: 2474726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The authors studied 24 cases of refractory premature beats by giving 0.1 adonisidum twice daily with Holter's monitoring. It was found that adonisidum was effective in 12 cases (P less than 0.001), or 50%. In another 8 patients adonisidum or mexiletine alone were ineffective for premature beats. However, when these patients were treated with both mexiletine and adonisidum, they responded with no exception (P less than 0.001). All 7 cases monitored with one hour Holter recording responded to adonisidum (P less than 0.001). As adonisidum tends to slow the heart rate, it is especially indicated for patients suffering from premature beats with increased heart rate, and should be used with caution in cases with slow heart rate or A-V block.
Collapse
|
535
|
Yu G, Watson RL, Bandong BB, Can C, Sampoll G, Moler E, Maurer RJ. Collisional quenching of 2 (3)P and 2 (4)P states in 33-MeV two- and three-electron Mg ions. PHYSICAL REVIEW. A, GENERAL PHYSICS 1989; 39:1041-1048. [PMID: 9901342 DOI: 10.1103/physreva.39.1041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
536
|
Yu G. [Immunohistochemical and histochemical study of malignant mesothelioma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1988; 17:280-2. [PMID: 2474381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
537
|
Li L, Yu G, Dong S, Wang G, Zhang Z. Adsorption active sites -Key factor on the adsorption ability of pyridine molecules on Ag surfaces. ACTA ACUST UNITED AC 1988. [DOI: 10.1007/bf00716086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
538
|
Smithgall TE, Yu G, Glazer RI. Identification of the differentiation-associated p93 tyrosine protein kinase of HL-60 leukemia cells as the product of the human c-fes locus and its expression in myelomonocytic cells. J Biol Chem 1988; 263:15050-5. [PMID: 3170574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A differentiation-associated 93-kDa tyrosine kinase (p93) was purified previously from the human promyelocytic leukemia cell line HL-60. The present study conclusively identifies p93 as the c-fes proto-oncogene product and shows that expression of p93c-fes and its associated tyrosine kinase activity are marked in mature granulocytes, monocytes, and human myeloid leukemia cell lines. Antisera to peptides obtained by expression of c-fes cDNA fragments in Escherichia coli reacted strongly with p93 purified from HL-60 cells. Western blots using one of these antisera demonstrated high levels of p93c-fes protein in normal human granulocytes and monocytes, as well as the cell lines KG-1, THP-1, HEL, and U-937, all of which can be induced to differentiate along the myelomonocytic pathway. Conversely, in cell lines resistant to myeloid differentiation, p93c-fes expression was either very low or absent. Expression of immunoreactive p93c-fes in these cell lines showed a strong positive correlation with p93c-fes tyrosine kinase activity, which was measured in cell extracts using a nondenaturing gel assay. Finally, the expression of p93c-fes, its tyrosine kinase activity, and the binding of 125I-granulocyte-macrophage colony-stimulating factor (GM-CSF) were all coordinately increased in HL-60 cells treated with the granulocytic differentiation inducer dimethyl sulfoxide, while all three parameters were low in untreated or differentiation-resistant HL-60 cells. These results suggest that expression of p93c-fes tyrosine kinase activity may be an essential component of myeloid differentiation and responsiveness to granulocyte-macrophage colony-stimulating factor.
Collapse
|
539
|
Yu G, Grant S, Glazer RI. Association of p93c-fes tyrosine protein kinase with granulocytic/monocytic differentiation and resistance to differentiating agents in HL-60 leukemia cells. Mol Pharmacol 1988; 33:384-8. [PMID: 3162757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A 93-kDa tyrosine protein kinase (p93) identified previously as the gene product of the c-fes proto-oncogene, is highly expressed in HL-60 leukemia cells induced to differentiate to the granulocyte or monocyte phenotype. We have now studied the relationship of p93 to the differentiation process by using a dimethyl sulfoxide (DMSO)-resistant subline of HL-60 cells (HL-60/DMSO) or the parental cell line treated with peptide or protein substrates of p93. Treatment of HL-60/DMSO cells with DMSO induced neither differentiation nor the expression of p93; however, cotreatment with IFN-alpha and DMSO resulted in partial differentiation and the concomitant induction of p93 activity. Treatment of wild-type HL-60 cells by the coaddition of the p93 substrates poly(Glu,Tyr)1:1, poly(Glu,Tyr)4:1, poly(Glu,Ala,Tyr)6:3:1, angiotensin II or vasoactive intestinal peptide with DMSO or IFN-tau partially blocked differentiation and concurrently diminished the induction of p93 activity. The inhibitory concentrations of the p93 substrates were related to their Km values. These results indicate that there is an obligatory association between the expression of p93 and granulocyte/monocyte differentiation in this cell line.
Collapse
|
540
|
|
541
|
Yu G, Glazer RI. Purification and characterization of p93fes- and p60src-related tyrosine protein kinase activities in differentiated HL-60 leukemia cells. J Biol Chem 1987; 262:17543-8. [PMID: 3480286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Two tyrosine protein kinase activities have been identified previously to be present in HL-60 leukemia cells during induction of granulocytic and monocytic differentiation with a variety of differentiating agents. We have copurified a membrane-associated tyrosine kinase (p93) and an activity associated with both the cytosol and membrane fractions (p60). Triton X-100 extracts from HL-60 cells treated with dimethyl sulfoxide were subjected to tyrosine-agarose chromatography, polypropyl aspartamide high performance liquid chromatography (HPLC), and HPLC using an antiphosphotyrosine IgG-derivatized column. Overall purification was 2700-fold for p93 and 1800-fold for p60. p60 and p93 are phosphorylated exclusively on tyrosine residues and can use poly(Glu,Tyr)4:1, histone H1 and vasoactive intestinal peptide as substrates. Poly(Glu,Tyr)1:1 and poly(Glu,Ala,Tyr)6:3:1 were less effective substrates for p60 and p93. The activity of p93 was dependent on Mg2+ or Mn2+, whereas p60 was dependent on Mg2+; however, the activity of p60 was stimulated in a synergistic manner by the presence of both Mg2+ and Mn2+, whereas the activity of p93 was not enhanced further by the combination of divalent ions. Both p60 and p93 were immunoprecipitated by an anti-v-src monoclonal antibody but only p93 was immunoprecipitated by an anti-v-fps/fes antibody. V8 protease digestion of p60 revealed one major proteolytic fragment containing phosphotyrosine, whereas V8 protease digestion of p93 produced two major peptides that were phosphorylated on tyrosine residues. These results suggest that, although p93 and p60 may possess some epitopic similarities, they have distinguishing phosphorylation sites. Moreover, p93, in contrast to p60, appears to be strictly associated with granulocytic/monocytic differentiation and related to the cellular fps/fes protooncogene.
Collapse
|
542
|
Yu G, Li WH. [Ultrastructural study of 12 cases of malignant mesothelioma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1987; 16:226-8, 40. [PMID: 2964925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
543
|
Glazer RI, Yu G, Knode MC. Analysis of tyrosine kinase activity in cell extracts using nondenaturing polyacrylamide gel electrophoresis. Anal Biochem 1987; 164:214-20. [PMID: 2445220 DOI: 10.1016/0003-2697(87)90388-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A general procedure for detecting tyrosine kinase activity in crude or purified preparations using nondenaturing gel electrophoresis is presented. Samples are resolved by electrophoresis in minigels which are then incubated in an assay mixture containing [gamma-32P]ATP, poly(glutamic acid, tyrosine)4:1, and cofactors. Subsequently, gels are fixed and washed in trichloroacetic acid-pyrophosphate, dried, and analyzed by autoradiography or liquid scintillation counting. The procedure is simple and fast and allows analysis of different molecular weight forms of tyrosine kinase under linear kinetics at 37 degrees C without interference from phosphatases and proteases.
Collapse
|
544
|
Wang KQ, Yu G, Gao WZ, Li W. [Absorption and distribution of a hematoporphyrin derivative in mice bearing tumors]. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1987; 8:90-2. [PMID: 2955667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
545
|
Wang NQ, Yu G, Liang YY, Ye AL, Zhang Y, Yuan QZ. [A comparative study on the photodynamic effect, photosensitive side action and toxicity of several China-made photosensitizers]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1986; 21:7-11. [PMID: 2425553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
546
|
Wisenbaugh T, Yu G, Evans J. The superiority of maximum fiber elastance over maximum stress-volume ratio as an index of contractile state. Circulation 1985; 72:648-53. [PMID: 4017216 DOI: 10.1161/01.cir.72.3.648] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The end-systolic pressure-volume relationship has been used as a load-independent measure of ventricular pump performance. Since comparisons of load between ventricles of different size and thickness may be more accurately made with measurements of wall stress than with those of pressure, the end-systolic stress-volume relationship at one or more levels of end-systolic stress has been used to estimate contractile function in hypertrophied ventricles. Linear regression of end-systolic stress against end-systolic volume for differently loaded beats has a slope termed maximum fiber elastance (fiber Emax) and a volume intercept termed Vo; the maximum stress-volume ratio (MSVR) for a single beat is an approximation of fiber Emax but assumes Vo = 0. However, the influence of preload, afterload, and inotropic state on these indexes has not been examined. We therefore studied the stress-volume relationship in seven open-chest dogs instrumented with ultrasonic crystals and micromanometers. Postextrasystolic potentiation (PESP) increased both the MSVR (5.7 +/- 1.83 vs 4.85 +/- 1.43 at control, p less than .05) and fiber Emax (13.93 +/- 3.24 vs 9.24 +/- 2.15 at control; p less than .05). Augmentation of preload by infusion of dextran, with the use of nitroprusside to maintain afterload relatively constant, did not significantly influence either the MSVR or fiber Emax. Vo was not significantly influenced by PESP, but was shifted to higher values by augmentation of preload (17.5 +/- 14.8 vs 13.9 +/- 11.1 ml at control; p less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
547
|
Abstract
A patient with pancreatic carcinoma presented with an initial left testicular mass that proved to be metastatic adenocarcinoma of the pancreas. Regional spread of the pancreatic carcinoma may have created venous and lymphatic obstruction with inferior passage of tumor emboli to the testis. A summary of nonlymphomatous secondary tumors of the testis also is presented.
Collapse
|
548
|
Jobe A, Ikegami M, Sarton-Miller I, Jones S, Yu G. Characterization of phospholipids and localization of some phospholipid synthetic and subcellular marker enzymes in subcellular fractions from rabbit lung. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 666:47-57. [PMID: 6271235 DOI: 10.1016/0005-2760(81)90089-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
549
|
Li WZ, Yu G. [Studies on the resistance of house-flies to dipterex and methods for its determination (author's transl)]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1981; 15:238-9. [PMID: 7333192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|
550
|
Cheng RS, Pomeranz B, Yu G. Electroacupuncture treatment of morphine-dependent mice reduces signs of withdrawal, without showing cross-tolerance. Eur J Pharmacol 1980; 68:477-81. [PMID: 7193585 DOI: 10.1016/0014-2999(80)90423-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Morphine pellets (75 mg morphine base per pellet) were implanted subcutaneously in mice (B6AF1/J) and were surgically removed after 3 or 8 days. During morphine abstinence (7 h after pellet removal), the mice were treated with electroacupuncture (EA). The results indicate that EA analgesia shows no cross-tolerance to morphine. Additionally, EA reduced withdrawal behaviour (jumping) in 50% of the mice during morphine abstinence.
Collapse
|