1501
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Xu D, Jiang C, Shi Y, Yu J, Sun L, Fan P, Liu X. Structure-function studies of the C-terminal alpha-helix of human interleukin-2 by site-directed mutagenesis. CHINESE JOURNAL OF BIOTECHNOLOGY 1993; 9:229-234. [PMID: 8061231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
By using oligonucleotide-mediated site-directed mutagenesis, we obtained three human interleukin-2 analogs with substitution of Pro in the C-terminal amphiphilic alpha-helix, 125Pro-IL-2, 127Pro-IL-2 and 125Pro-127Pro-IL-2. The bioactivities of all these analogs were decreased. The extent of the decrease in bioactivity coincided with the degrees of secondary and tertiary structure destroyed, as evaluated by circular dichroism and intrinsic fluorescence analysis. The results suggested that the integrity of the hydrophobic face in the C terminal alpha-helix is crucial for the structure and function of interleukin-2.
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1502
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Shi Y, Amellem O, Pettersen EO. Hypoxia-associated proteins in human cells cultivated in vitro: lack of association with hypoxia-induced cell cycle regulation. APMIS 1993; 101:75-82. [PMID: 8457329 DOI: 10.1111/j.1699-0463.1993.tb00084.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The synthesis of proteins expressed in human NHIK 3025 cells following exposure to extremely hypoxic conditions (< 4 ppm O2) has been studied. Populations of cells, either in exponential growth or synchronized by the method of detaching mitotic cells, were exposed to extremely hypoxic conditions for up to 20 h. The rate of total protein synthesis was measured at various time points after reoxygenation, and it appeared to be relatively constant and similar to the control level. The protein expression in cells was studied by pulse labelling for 1 h with [35S]-methionine, and subsequently visualized by SDS-PAGE and autoradiography. Six proteins appeared to have a changed expression after exposure to extreme hypoxia as compared to control cells; four of them (45, 80, 100 and 150 kD) showed increased, while two (46 and 90 kD) showed decreased expression. The response of these proteins to extreme hypoxia seems to be relatively slow, i.e. with half-times of several hours. Since extreme hypoxia influences cell cycle progression by instantaneous blockage at the G1/S border as well as halting DNA synthesis in S cells, these proteins can hardly cause these effects. Neither is the altered expression of these proteins due to the accumulation of G1 cells caused by hypoxia.
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1503
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Baekkeskov S, Aanstoot HJ, Fu Q, Jaffe M, Kim J, Quan J, Richter W, Shi Y. The glutamate decarboxylase and 38KD autoantigens in type 1 diabetes: aspects of structure and epitope recognition. Autoimmunity 1993; 15 Suppl:24-6. [PMID: 7692998 DOI: 10.3109/08916939309008857] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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1504
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Shi Y, Gong C. Dynamical properties of a Cartesian product of two fractals. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 46:8009-8010. [PMID: 9908153 DOI: 10.1103/physreva.46.8009] [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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1505
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Shi Y, Marsili PM, Dai WW, Granié M, Morucci JP. Application of the boundary element method to the study of boundary potentials in electrical impedance tomography. CLINICAL PHYSICS AND PHYSIOLOGICAL MEASUREMENT : AN OFFICIAL JOURNAL OF THE HOSPITAL PHYSICISTS' ASSOCIATION, DEUTSCHE GESELLSCHAFT FUR MEDIZINISCHE PHYSIK AND THE EUROPEAN FEDERATION OF ORGANISATIONS FOR MEDICAL PHYSICS 1992; 13 Suppl A:139-43. [PMID: 1587088 DOI: 10.1088/0143-0815/13/a/027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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1506
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Green DR, Bissonnette RP, Glynn JM, Shi Y. Activation-induced apoptosis in lymphoid systems. Semin Immunol 1992; 4:379-88. [PMID: 1286165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Lymphocytes become activated when antigen receptors on the cell surface are cross-linked, or when they are exposed to agents that mimic this signal. Although such activation is usually associated with the production of immune mediators (e.g. antibodies, cytokines) and entry into the cell cycle, it can alternatively lead to death via apoptosis. This activation-induced apoptosis was first observed in developing lymphocytes and has been proposed as a mechanism for negative selection, by which immature cells with potential for autoreactivity are eliminated from the maturation pathway. Activation-induced apoptosis has also been observed in normal, mature lymphocytes under some conditions, and this may account for the phenomena of peripheral deletion, in which mature T cells are eliminated upon exposure to high doses of antigen. It may also be an important mechanism whereby CD4+ T cells are depleted in HIV+ individuals. Although the phenomenon of activation-induced apoptosis is not understood, recent studies have begun to implicate specific signal transduction pathways and gene products in the process. Among the latter is the c-myc proto-oncogene, which paradoxically can play an essential role in several forms of apoptosis, including that induced by activation of lymphocytes.
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1507
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Morucci JP, Shi Y, Rigaud B. The modulation transfer function in impedance imaging. CLINICAL PHYSICS AND PHYSIOLOGICAL MEASUREMENT : AN OFFICIAL JOURNAL OF THE HOSPITAL PHYSICISTS' ASSOCIATION, DEUTSCHE GESELLSCHAFT FUR MEDIZINISCHE PHYSIK AND THE EUROPEAN FEDERATION OF ORGANISATIONS FOR MEDICAL PHYSICS 1992; 13 Suppl A:161-6. [PMID: 1587093 DOI: 10.1088/0143-0815/13/a/031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The concepts of the point spread function (PSF) and its Fourier transform, the modulation transfer function (MTF) are introduced to evaluate an impedance imaging system. The effects of some practical factors which should be taken into account in calculating the MTF are analysed. Experimental results from the groups in Sheffield, Barcelona and Toulouse are presented.
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1508
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Abstract
Conventional and thiophosphonate-derivatized oligonucleotides were employed to specifically regulate functional gene expression in murine T-cell hybridomas. For example, induction of apoptotic cell death following activation of T-cell hybridomas was examined using antisense oligonucleotides corresponding to several protooncogenes. We found that antisense oligodeoxynucleotides corresponding to c-myc inhibited both the characteristic DNA fragmentation and the loss of cell viability following activation without affecting production of lymphokines. Functional antisense oligonucleotides corresponding to c-fos had no effect in this system. These results demonstrate the use of antisense oligonucleotides to regulate function in T-cell hybridomas and provide valuable insights into the molecular bases of this biological phenomenon. Antisense oligonucleotides were also used to study another problem, the relation of T-cell-derived antigen-specific immunoregulatory factors to the T-cell receptor (TCR). Because the translation start of each TCR gene usually varies from one T cell to another, antisense oligonucleotides corresponding to the TCR V alpha or V beta of different cells were shown to act in a cell-specific manner. Furthermore, this method was used to demonstrate that a soluble antigen-specific regulatory activity produced by one of the T-cell lines depends on expression of the specific TCRa, an observation that has since been confirmed by gene transfer experiments. Expression of the CD3-TCR complex on the cell surface was also blocked by antisense oligonucleotides corresponding to CD3 gamma and CD3 zeta; however, neither these nor TCR V beta antisense oligonucleotides had any effect on production of the soluble regulatory activity.
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1509
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Lee TC, Shi Y, Schwartz RJ. Displacement of BrdUrd-induced YY1 by serum response factor activates skeletal alpha-actin transcription in embryonic myoblasts. Proc Natl Acad Sci U S A 1992; 89:9814-8. [PMID: 1409704 PMCID: PMC50223 DOI: 10.1073/pnas.89.20.9814] [Citation(s) in RCA: 182] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Muscle-restricted transcription of the skeletal alpha-actin gene is controlled in part by a positive regulator, serum response factor (SRF), and a negative regulator, F-ACT1, which bind competitively to the most proximal serum response element (SRE1). We show here that F-ACT1 is identical to a transcription factor recently cloned and described as YY1, NF-E1, delta, or UCRBP. We found that although the DNA-binding activity of SRF accumulates during myogenesis, that of YY1 diminishes simultaneously. Myoblasts rendered incapable of differentiation by BrdUrd treatment exhibited the highest level of YY1 and the lowest level of SRF activities. Transfected SRF could directly transactivate the skeletal alpha-actin promoter by overcoming the inhibitory effect of BrdUrd-induced YY1. The transactivation depends on intact SRE DNA elements and requires the DNA-binding/dimerization domain of SRF as well as its C-terminal half rich in serines and threonines. Since the functions of YY1 and SRF appear to be developmentally regulated, the convergence of their binding sites upon the SRE constitutes an integrated mechanism whereby temporal and spatial muscle gene expression may be accomplished.
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1510
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Li R, Shi Y, Thomas JO. Intracellular distribution of a nuclear localization signal binding protein. Exp Cell Res 1992; 202:355-65. [PMID: 1356819 DOI: 10.1016/0014-4827(92)90085-m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The transport of proteins into the nucleus requires the recognition of a nuclear localization signal sequence. Several proteins that interact with these sequences have been identified, including one of about 66 kDa. We have prepared antibodies that recognize the 66-kDa nuclear localization signal binding protein (NLSBP) and inhibit nuclear localization in vitro. By immunofluorescence, it is seen that the NLSBP is predominantly cytoplasmic and is distributed peripherally around the nucleus and the microtubule organizing center. There is also a weak punctate staining of the surface of the nucleus. Methanol-fixed cells can also be stained directly with fluorescently labeled karyophilic proteins. These stains reveal the same cytoplasmic structures as anti-NLSBP. The expression of the NLSBP is growth dependent. When cells grown to confluence are examined, the cytoplasmic staining is greatly reduced, leaving the punctate nuclear staining as the predominant feature. In serum-starved cells, very little staining of either the cytoplasm or the nucleus can be seen. Upon simulation by the addition of serum, the original cytoplasmic and nuclear envelope staining is restored. Cells grown in the presence of colchicine or taxol have an altered NLSBP distribution but apparently normal cytoplasmic nuclear transport.
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1511
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Shi Y, Zou M, Robb D, Farid NR. Typing for major histocompatibility complex class II antigens in thyroid tissue blocks: association of Hashimoto's thyroiditis with HLA-DQA0301 and DQB0201 alleles. J Clin Endocrinol Metab 1992; 75:943-6. [PMID: 1517390 DOI: 10.1210/jcem.75.3.1517390] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This study was undertaken 1) to find out whether we can type major histocompatibility class II antigens from the paraffin-embedded series of thyroid tissue, and 2) to investigate whether HLA-DQ genes are involved in conferring a risk of Hashimoto's thyroiditis. To this end we used the polymerase chain reaction to amplify DNA from paraffin-embedded thyroid tissue blocks of histologically proven Hashimoto's disease. We used 46 specimens for HLA-DQA and 32 for DQB typing. The alleles were identified by sequence-specific oligonucleotide hybridizations. Fifty controls from the same geographic region were also typed using peripheral leukocyte DNA. HLA-DQA0301 (in linkage disequilibrium with DR4) was significantly increased (58.7% vs. 32% in controls; chi 2 = 6.73; P less than 0.01) in patients compared to controls. DQB0201 (in linkage disequilibrium with DR3) was also increased in the patient group (66% vs. 36% in controls; chi 2 = 6.63; P less than 0.01). Although DQA0301/DQB0201 heterozygotes (18.8%) were increased in patients compared to controls (6%), the difference was not significant. However, 81% of the patients (26 of 32) were DQA0301 and/or DQB0201 positive compared to 48% of controls (chi 2 5.98; P less than 0.05). We conclude that it is feasible to type HLA antigens from tissue blocks and that susceptibility to Hashimoto's disease is probably mediated through two pathways: DQA0301/DR4 and DQB0201/DR3.
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1512
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Shi Y, Zalewski A, Bravette B, Maroko AR, Maroko PR. Selective dopamine-1 receptor agonist augments regional myocardial blood flow: Comparison of fenoldopam and dopamine. Am Heart J 1992; 124:418-23. [PMID: 1353297 DOI: 10.1016/0002-8703(92)90607-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A new class of vasodilators exhibiting selective dopamine-1 receptor agonist activity is being introduced into clinical practice. Inasmuch as various vasodilators either augment or decrease myocardial blood flow ("coronary steal") depending on their pharmacologic action, the goal of this study was to assess the effects of fenoldopam (selective dopamine-1 receptor agonist) and dopamine (nonselective dopamine-1 receptor agonist) on regional myocardial blood flow in the presence of coronary occlusion. Accordingly, in 16 dogs anesthetized with pentobarbital, the left anterior descending coronary artery was occluded. Cardiovascular and renal hemodynamic effects were measured before and after intravenous infusion of renal equipotent doses of either fenoldopam (n = 9, 0.1 micrograms/kg/min) or dopamine (n = 7, 1 micrograms/kg/min). Both fenoldopam and dopamine caused a significant and comparable increase in renal blood flow. Fenoldopam but not dopamine significantly decreased the calculated peripheral vascular resistance and subsequently increased cardiac output. Dopamine had no effect on regional myocardial blood flow. In contrast, fenoldopam augmented transmural myocardial blood flow in normal (from 114 +/- 10 to 188 +/- 27 ml/100 gm/min, p less than 0.02) and ischemic border myocardium (from 45 +/- 5 to 68 +/- 11 ml/100 gm/min, p less than 0.03 and p less than 0.02 vs dopamine). There was a significant increase in blood flow to both the endocardial and epicardial layers of normal and ischemic border myocardium. These changes were accompanied by a significant reduction in coronary vascular resistance in the normal myocardium.(ABSTRACT TRUNCATED AT 250 WORDS)
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1513
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Shi Y, Weimer PJ. Response surface analysis of the effects of pH and dilution rate on Ruminococcus flavefaciens FD-1 in cellulose-fed continuous culture. Appl Environ Microbiol 1992; 58:2583-91. [PMID: 1514805 PMCID: PMC195825 DOI: 10.1128/aem.58.8.2583-2591.1992] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The ruminal cellulolytic bacterium Ruminococcus flavefaciens FD-1 was grown in cellulose-fed continuous culture with 20 different combinations of pH and dilution rate (D); the combinations were selected according to the physiological pH range of the organism (6.0 to 7.1) and growth rate of the organism on cellulose (0.017 to 0.10 h-1). A response surface analysis was used to characterize the effects of pH and D on the extent of cellulose consumption, growth yield, soluble sugar concentration, and yields of fermentation products. The response surfaces indicate that pH and D coordinately affect cellulose digestion and growth yield in this organism. As expected, the net cellulose consumption increased with increasing D while the fraction of added cellulose that was utilized decreased with increasing D. The effect of changes in pH within the physiological range on cellulose consumption was smaller than that of changes in D. Cellulose degradation was less sensitive to low pH than to high pH. At low Ds (longer retention times), cellulose degradation did not follow first-order kinetics. This decreased rate of cellulose digestion was not due to poor mixing, limitation by other medium components, or preferential utilization of the more amorphous fraction of the cellulose. The cell yield increased from 0.13 to 0.18 mg of cells per mg of cellulose with increasing Ds from 0.02 to 0.06 h-1 and decreased when the pH was shifted from the optimum of 6.5 to 6.8. The effect of pH on cell yield increased with increasing D. The reduced cell yield at low pH appears to be due to both an increase in maintenance energy requirements and a decrease in true growth yield.
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1514
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Shi Y. [Lung sound analysis of upper airway obstruction]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1992; 15:228-30, 256. [PMID: 1339160] [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 frequency spectrum of stridor was studied by the computer program in the patients with upper airway obstruction. The results showed that the peak frequency of respiratory sound increased significantly, the frequency spectrum got wider and removed to the high frequency area above 200Hz, the E ratio was smaller than 1. These changes were more apparent during inspiration than those during expiration. It is concluded that the stridorous sound could be determined exactly and quantitatively, and differentiated from wheezing by the spectral analysis.
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1515
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Shi Y, Glynn JM, Guilbert LJ, Cotter TG, Bissonnette RP, Green DR. Role for c-myc in activation-induced apoptotic cell death in T cell hybridomas. Science 1992; 257:212-4. [PMID: 1378649 DOI: 10.1126/science.1378649] [Citation(s) in RCA: 561] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Immature T cells and some T cell hybridomas undergo apoptotic cell death when activated through the T cell receptor complex, a phenomenon that is probably related to antigen induced negative selection of developing T cells. This activation-induced apoptosis depends on active protein and RNA synthesis in the dying cells, although none of the genes required for this process have previously been identified. Antisense oligonucleotides corresponding to c-myc block the constitutive expression of c-Myc protein in T cell hybridomas and interfere with all aspects of activation-induced apoptosis without affecting lymphokine production in these cells. These data indicate that c-myc expression is a necessary component of activation-induced apoptosis.
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MESH Headings
- Animals
- Antigens, Differentiation, T-Lymphocyte/physiology
- Base Sequence
- Blotting, Western
- CD3 Complex
- Cell Death/drug effects
- Cell Death/genetics
- Flow Cytometry
- Gene Expression/drug effects
- Genes, fos/physiology
- Genes, myc/physiology
- Hybridomas
- Lymphocyte Activation/drug effects
- Lymphocyte Activation/physiology
- Molecular Sequence Data
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/pharmacology
- Proto-Oncogene Proteins c-myc/biosynthesis
- RNA/biosynthesis
- Receptors, Antigen, T-Cell/physiology
- T-Lymphocytes/physiology
- Transcription, Genetic
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1516
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el Rouby S, Shi Y, Reem GH. Comparison of the properties of the CsA analogs monoacetyl CyC (o-acetyl-threonine2 cyclosporin) and methyl-alanyl CsA (N-methyl-L-alanyl6 cyclosporin); monoacetyl cyclosporin is immunosuppressive without binding to cyclophilin. Clin Exp Immunol 1992; 89:136-42. [PMID: 1628422 PMCID: PMC1554393 DOI: 10.1111/j.1365-2249.1992.tb06892.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Cyclosporin (CsA) is an immunosuppressant which binds to cyclophilin (Cyp). The relationship between Cyp binding and immunosuppression has been questioned since one of the analogs of CsA, N-methyl-L-alanyl6 cyclosporin (methyl-alanyl CsA) binds to Cyp but is not immunosuppressive. We compared the immunosuppressive properties of CsA, methyl-alanyl CsA and o-acetyl-threonine2 cyclosporin (monoacetyl CyC), since monoacetyl CyC does not bind to Cyp when tested in cell-free assays and its immunosuppressive properties had not been tested. Cyp is a peptidyl-prolyl isomerase which is abundant in all human tissues, yet the activities of CsA are mostly confined to inhibition of T cell and thymocyte activation, and to neuro- and nephro-toxicity and are independent of inhibition of the isomerase. Activation of thymocytes and of T cells is regulated by the binding of a nuclear factor(s) (NFs) to the NF-AT region (-285 to -255) of the IL-2 promoter. We studied inhibition of binding to the NF-AT region of NFs derived from primary cultures of thymocytes treated with CsA or its analogs. In addition, we compared the effect of CsA and its analogs on the expression of the IL-2 gene in a stably transfected Jurkat-cell line (Fgl 5) which contains three copies of NF-AT and the reporter enzyme beta-galactosidase; and on inhibition of proliferation induced by concanavalin A (Con A) or IL-2. We found that monoacetyl CyC which does not bind to Cyp is immunosuppressive by our criteria when tested in cultured cells due to either a different mechanism of action or to metabolic activation.
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1517
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He G, Yin S, Liu Y, Shi Y, Xu H, Zhao X, Pu Q, Zhang Y. [Isolation and identification of a strain of Pseudomonas SP. producing insoluble glucan hydrolase]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1992; 23:156-9. [PMID: 1452147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A strain, CIB871, isolated from the natural world can hydrolyze insoluble glucan(IG) produced by S. mutans. This organism has been identified to be a strain of Pseudomonas SP. It grows well at 30 degrees C. The optimum medium for producing insoluble glucan hydrolase (IGase) is composed of 0.3% peptone, 0.03% IG and M1 salt solution (NH4)2 SO4 1mg/ml, MgSO4 50 micrograms/ml, FeCl2 50 micrograms/ml, K2HPO4 0.5mg/ml). The IGase production reached maximum when cultured for 65-70 hours.
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1518
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Li M, Sun Z, Shi Y. [The construction of rich genomic library of bovine Y chromosome]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1992; 23:133-6. [PMID: 1452141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
According to the fundamentals of DNA renatured kinetics, we made a study in which genomic DNA from male cattle was completely digested with Sau 3A, while female DNA was sheared to an average size of 500 bp fragments. The Y derived DNA sequence rich library of bovine has been contracted with pUC19 plasmid as vector and JM109 as host bacteria by reassociation of male and female DNA. Male and female DNA probes, were used. The result of colony hybridization showed that out of 1000 recombinants analysed, 6 were found to be stronger signal with male probe. Analysis of Pvu' I digested DNA fragment revealed that most of the inserts were in the 90-300 bp.
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1519
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Shi Y, Thomas JO. The transport of proteins into the nucleus requires the 70-kilodalton heat shock protein or its cytosolic cognate. Mol Cell Biol 1992; 12:2186-92. [PMID: 1569948 PMCID: PMC364390 DOI: 10.1128/mcb.12.5.2186-2192.1992] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The 70-kDa heat shock protein hsp70 and its constitutively expressed cognate, hsc70, are abundant proteins implicated in a number of cellular processes. When a permeabilized cell system for examining the transport of proteins into the nucleus is depleted of hsc70 and hsp70, either by affinity chromatography on ATP-agarose or with antibodies against these proteins, nuclear transport activity is lost. Full activity is restored by the addition of HeLa proteins that bind to ATP-agarose. hsc70 and hsp70 are the active factors, since activity is also fully restored by the addition of either recombinant hsc70 or hsp70 which has been bacterially expressed and highly purified. The restoration of activity is saturable. The transport system requires other cytosolic factors as well, including at least one protein that is sensitive to inactivation by N-ethylmaleimide, but neither hsc70 nor hsp70 is the sensitive protein.
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1520
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Shi Y, Sheng GK, Wang JH, Qin SW. Plasma levels of tumor necrosis factor during neonatal sepsis. J Pediatr 1992; 120:831. [PMID: 1578325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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1521
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Liu J, Shi Y. [Advances in the therapy of cerebral glioma]. ZHONGHUA SHEN JING JING SHEN KE ZA ZHI = CHINESE JOURNAL OF NEUROLOGY AND PSYCHIATRY 1992; 25:120-3. [PMID: 1499409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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1522
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Zarutskie PW, Bowman JC, Shi Y, Moore DE, Soules MR. Early luteal progesterone supplementation during in vitro fertilization cycles. A randomized trial. THE JOURNAL OF REPRODUCTIVE MEDICINE 1992; 37:210-4. [PMID: 1564703] [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 effects of early luteal phase progesterone (P) supplementation were studied in women with endogenous serum P levels less than or equal to 12 ng/mL prior to embryo transfer. From a total of 129 cycles that received the same ovarian hyperstimulation protocol, 72 cycles were characterized by levels less than 12 ng/mL on the day prior to embryo transfer. Of those women, 42 (group B) were started on P supplementation one day prior to embryo transfer, and 30 (group C) were started according to the standard protocol after embryo transfer. The clinical course and outcomes in both groups were compared with 57 cycles that had P levels greater than or equal to 12 ng/mL (group A). The early P supplementation in group B resulted in a transient increase in P levels on the morning of embryo transfer as compared with group C. It did not, however, approach the levels seen in group A, which had higher P levels from the early luteal phase through embryo transfer and more favorable oocyte recovery, fertilization and cleavage rates. We were unable to improve the clinical outcome in group B as compared with group C by providing earlier P supplementation.
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1523
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Chen Z, Chen Y, Shi Y, Yie X, Yang G. Microcarrier culture of fish cells and viruses in cell culture bioreactor. Can J Microbiol 1992; 38:222-5. [PMID: 1393824 DOI: 10.1139/m92-037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This article deals with the culture of grass carp (Ctenopharyngodon idellus) lip and embryo cells on Cytodex 3 and GT-2 microcarriers in a 1.5-L cell culture bioreactor to propagate grass carp hemorrhage virus. The cells and viruses were successfully cultivated at 26 degrees C, pH 7.0, and dissolved oxygen 40% of air saturation. The cell density achieved was as high as 7.4 x 10(6) cells/mL, and the virus titre reached 6.75 log LD50/0.5 mL from an initial 3.00 log LD50/0.5 mL. The results present broad prospects for fish virus vaccine production.
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1524
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Shi Y, Barmes D, Bratthall D, Leclercq MH. WHO pathfinder caries survey in Beijing extended with data for prevalence of mutans streptococci. Int Dent J 1992; 42:31-6. [PMID: 1563820] [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
A pathfinder caries survey was carried out in Beijing, People's Republic of China, using WHO standard methodologies, in order to estimate the trend by comparing the results with the 1981 caries survey, performed in the same area. Simultaneously, the levels of mutans streptococci in the group were estimated in order to define the proportion of children with high and low mutans levels. Twelve-year-old children were randomly selected from schools in five districts within the city limits. Examinations for caries were performed according to 'WHO Oral Health Surveys' by two calibrated examiners. A total of 178 children were examined for caries and 156 of them were randomly selected for saliva sampling of mutans streptococci, using the 'Strip mutans' method. The number of colonies adhering to the strips were compared with a chart, supplied by the manufacturer, and given a score between 0 and 3, indicating low to very high saliva mutans counts, respectively. The results showed a mean DMFT of 1.87 (1.61-0.06-0.20, for decayed, missing and filled teeth respectively); 66.3 per cent of the children were affected. Fourteen per cent had mutans class 0, 28 per cent class 1, 35 per cent class 2 and 23 per cent class 3. The mean DFT, for each mutans class was 0.82, 1.48, 2.09 and 2.69, respectively. The differences were statistically significant (P = 0.0015). In the lowest mutans class, 50 per cent had caries and the mean number of teeth requiring conservative care was 0.68. For the high mutans group, the corresponding values were 72 per cent and 2.11 teeth.(ABSTRACT TRUNCATED AT 250 WORDS)
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Shi Y, Nardone D, Hernandez-Martinez A, Walinsky P, Bjornsson TD, Zalewski A. Fibrinolytic activity after vessel wall injury. J Am Coll Cardiol 1992; 19:441-3. [PMID: 1531060 DOI: 10.1016/0735-1097(92)90502-e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The goal of this study was to assess fibrinolytic activity after vessel wall injury and to correlate changes in fibrinolytic activity with angiographic and histologic findings. Accordingly, in 18 atherosclerotic rabbits, vessel wall injury was produced by means of iliac artery balloon angioplasty (the injury group), whereas 8 atherosclerotic rabbits served as a control group. In all rabbits from the injury group, deep vessel wall injury was documented by either angiography or histologic study. Plasminogen activator inhibitor-1 activity in plasma increased significantly, from 21.79 +/- 1.29 arbitrary units/ml (AU/ml) at baseline study to 32.05 +/- 1.47 AU/ml at 6 h after vessel wall injury (p less than 0.01), whereas activity remained unchanged throughout the 24-h period in the control group. Plasma levels of tissue plasminogen activator activity were similar in both groups. Intravascular thrombus was found in five of six additional rabbits 6 h after vessel wall injury, that is, at the time of impaired fibrinolytic activity, whereas no thrombus was found in the control group (p less than 0.05). It is concluded that deep vessel wall injury is associated with reduced fibrinolytic activity. In addition to other procoagulant factors, elevated plasminogen activator inhibitor-1 activity may lead to intravascular thrombosis and impaired resolution of thrombus.
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