451
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Zhou P, Makivic M, Zuo F, Zane S, Miller JS, Epstein AJ. Ferromagnetic behavior and magnetic excitations in a molecular-based alternating-spin chain: Decamethylchromocenium tetracyanoethanide. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:4364-4367. [PMID: 10011347 DOI: 10.1103/physrevb.49.4364] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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452
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Zhou P, Xu Y, Ma Y, Liu H. [Amplification of 16S rDNAs from halobacteria by means of PCR technique]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1994; 34:6-8. [PMID: 8209549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The 16S rDNAs have been amplified from four halobacteria Haloarcula vallismortis (EM201), Haloferax denitrificans (EM303). A5 and B2 through a set of specific primers using the PCR technique. The molecule of the PCR products is about 1.47 kb. The hybridization results also show that these PCR products have DNA homology with halobacteria.
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453
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Cunningham RK, Thacore HR, Zhou P, Nakeeb S, Zaleski MB. Blood transfusion as a means for transmission of retrovirus-induced lymphoproliferative disease in mice. Int Arch Allergy Immunol 1994; 103:16-22. [PMID: 8260846 DOI: 10.1159/000236600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Lymphoproliferative disease was elicited in C57BL/6KH and (BALB/c x C57BL/6)F1 hybrids by a single intraperitoneal injection of 10(5) FFU of LP-BM5 virus preparation. The disease could reproducibly be transferred by a single intravenous transfusion of 0.2 ml of whole blood as well as 0.1 ml of blood cells, plasma or serum from the infected animals. F1 hybrids displayed a delayed development of the disease when an acellular virus preparation was administered, but they were fully susceptible to the disease when syngeneic blood from infected F1 donors was transfused. Blood from donors in the prodromal stage was as effective in transmission of the disease as blood from donors with fully developed disease. This indicated that in murine lymphoproliferative disease viremia develops very early in the course of the disease. It seems that using the blood transfusion one could develop a reliable semiquantitative assay for the infectiveness of the animals suffering from LP-MB5-induced lymphoproliferative disease.
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454
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Barna BP, Thomassen MJ, Maier M, Medendorp SV, Tubbs RR, Chiang T, Zhou P, Yen-Lieberman B, Singh-Burgess S, Deodhar SD. Combination therapy with a synthetic peptide of C-reactive protein and interleukin 2: augmented survival and eradication of pulmonary metastases. Cancer Immunol Immunother 1994; 38:38-42. [PMID: 8299117 PMCID: PMC11038352 DOI: 10.1007/bf01517168] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/1993] [Accepted: 08/24/1993] [Indexed: 01/29/2023]
Abstract
A synthetic peptide (RS-83277) derived from the structure of human C-reactive protein (CRP) was previously shown to have antitumor activity in three different murine tumor models when administered in multilamellar vesicles (MLV). The therapeutic effects were comparable to those seen with MLV-encapsulated native CRP. The present study evaluated the therapeutic and immunomodulatory effects of administering CRP peptide RS-83277 MLV simultaneously with low-dose recombinant interleukin-2 (IL-2) to C57Bl/6 mice bearing established pulmonary metastases of fibrosarcoma T241. Results demonstrated that the capacity of RS-83277 MLV to inhibit tumor metastases and prolong survival was significantly augmented by combination with 10,000 U/day IL-2 i.p. Treated animals showed no evidence of toxicity. By immunohistochemistry, increased Thy 1.2+ cells were detectable in lungs of RS-83277 MLV/IL-2-treated animals compared to those receiving RS-83277 MLV alone. Circulating tumor necrosis factor alpha (TNF) and interferon (IFN) were not detectable in animals receiving RS-83277 MLV alone, but TNF was significantly elevated in animals receiving IL-2. In the presence of combination therapy, however, circulating TNF was not detectable. Results suggest that the combination of synthetic CRP peptide RS-83277 MLV and low-dose IL-2 offers a therapeutic advantage over either agent alone.
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455
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Jiang W, Kahn SM, Zhou P, Zhang YJ, Cacace AM, Infante AS, Doi S, Santella RM, Weinstein IB. Overexpression of cyclin D1 in rat fibroblasts causes abnormalities in growth control, cell cycle progression and gene expression. Oncogene 1993; 8:3447-57. [PMID: 8247550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cyclin D1, a putative G1 cyclin, has been implicated in cell cycle control. The human cyclin D1 gene is located on chromosome 11q13 where DNA rearrangement and amplification have been detected in several types of human cancer. Previous studies demonstrated that the cyclin D1 gene is not only rearranged or amplified but also overexpressed in some of these human tumors and tumor-derived cell lines. To further address the roles of cyclin D1 in cell cycle control and tumorigenesis, we have stably overexpressed the human cyclin D1 cDNA in Rat6 embryo fibroblasts by using retrovirus mediated transduction. The cyclin D1 protein was overproduced about 10-fold and was localized predominately in the nucleus. Cyclin D1 overexpressing cells displayed a decrease in the duration of the G1 phase, decreased cell size, and induced tumors when injected into athymic (nude) mice. In addition, overexpression of cyclin D1 in Rat6 cells perturbed the expression of several cellular growth-related genes including c-myc, c-jun, and cyclin A, but not cyclin D3. Taken together, these results indicate that deregulated expression of the cyclin D1 gene can cause disturbances in cell cycle control and gene expression and also enhance tumorigenesis.
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MESH Headings
- Animals
- Blotting, Northern
- Blotting, Western
- Cell Cycle/physiology
- Cell Division/physiology
- Cell Nucleus/chemistry
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/pathology
- Cells, Cultured
- Chromosome Mapping
- Chromosomes, Human, Pair 11
- Cyclin D1
- Cyclins/analysis
- Cyclins/genetics
- Cyclins/physiology
- DNA/analysis
- DNA/genetics
- Embryo, Mammalian/chemistry
- Embryo, Mammalian/cytology
- Fibroblasts/chemistry
- Fibroblasts/cytology
- Fibroblasts/metabolism
- Flow Cytometry
- G1 Phase
- Gene Amplification
- Gene Expression/genetics
- Gene Expression/physiology
- Humans
- Immunohistochemistry
- Mice
- Mice, Nude
- Oncogene Proteins/analysis
- Oncogene Proteins/genetics
- Oncogene Proteins/physiology
- Proto-Oncogene Proteins c-jun/analysis
- Proto-Oncogene Proteins c-jun/genetics
- Proto-Oncogene Proteins c-myc/analysis
- Proto-Oncogene Proteins c-myc/genetics
- Rats
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456
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Watson DG, Zhou P, Midgley JM, Milligan CD, Kaiser K. The determination of biogenic amines in four strains of the fruit fly Drosophila melanogaster. J Pharm Biomed Anal 1993; 11:1145-9. [PMID: 8123727 DOI: 10.1016/0731-7085(93)80096-j] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A range of biogenic amines were measured in the heads from four strains of Drosophila melanogaster. Quantitation was carried out using gas chromatography-negative ion chemical ionization mass spectrometry (GC-NICIMS) with stable isotope dilution. The principal amines detected in the heads were dopamine, noradrenaline and 5 HT with small amounts of p- and m-tyramine; p-octopamine could not be detected in samples of 25 heads with a limit of detection of 10 pg per sample. In addition to conventional neurotransmitters or putative neurotransmitters the amines 5- and 6-hydroxydopamine were detected in the heads in substantial amounts.
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457
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Zhou P, Wang KA, Eklund PC, Dresselhaus G, Dresselhaus MS. Raman-scattering study of the electron-phonon interaction in M3C60 (M=K,Rb). PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:8412-8417. [PMID: 10007037 DOI: 10.1103/physrevb.48.8412] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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458
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Zhou P, Thiele DJ. Rapid transcriptional autoregulation of a yeast metalloregulatory transcription factor is essential for high-level copper detoxification. Genes Dev 1993; 7:1824-35. [PMID: 8370529 DOI: 10.1101/gad.7.9.1824] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Copper detoxification in the yeast Candida glabrata is carried out in large part by a family of metallothionein (MT) genes: a unique MT-I gene, a tandemly amplified MT-IIa gene, and a single unlinked MT-IIb gene. In response to elevated environmental copper levels, members of this MT gene family are transcriptionally activated by a copper-dependent, sequence-specific DNA-binding transcription factor, AMT1. AMT1 shares several structural and functional features with the Saccharomyces cerevisiae copper metalloregulatory transcription factor ACE1, which is constitutively expressed and poised for rapid transcriptional responses to the toxic metal copper. In this paper, we demonstrate that AMT1 is subject to positive transcriptional autoregulation, which is exerted through binding of copper-activated AMT1 to a single copper responsive element in the AMT1 promoter. A nonautoregulatory amt1 mutant displayed a marked decrease in both copper tolerance and expression of the MT-II genes, which are critical for high-level copper detoxification in Candida glabrata. Kinetic analysis demonstrated the remarkably rapid AMT1 mRNA accumulation in the presence of copper, which is followed by increased expression of the metallothionein gene products. These results demonstrate that AMT1-positive autoregulation plays a critical role in metal detoxification and suggest that the rapid autoactivation of the AMT1 metalloregulatory transcription factor biosynthesis is essential for C. glabrata to quickly build up a cellular defense line to protect cells upon exposure to high environmental copper levels.
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459
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Zanelli E, Zhou P, Cao H, Smart MK, David CS. Genomic organization and tissue expression of the mouse proteasome gene Lmp-7. Immunogenetics 1993; 38:400-7. [PMID: 8406612 DOI: 10.1007/bf00184520] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
LMP7 is one of the two proteasome subunits encoded in the major histocompatibility complex and is speculated to play a role in the generation of endogenous peptides for presentation by class I molecules to cytotoxic T cells. Here we report the genomic organization of the mouse Lmp-7 gene and the tissue distribution of its messenger RNA. In contrast to human LMP7 which is composed of seven exons and six introns, the mouse Lmp-7 gene is organized in six exons and five introns. Interestingly, the region corresponding to the first exon of human LMP7 is highly modified by numerous insertions and deletions and contains two in frame stop codons. Consequently, the mouse Lmp-7 gene does not allow the alternative exon usage described in humans and most likely encodes for only one LMP7 protein. Thus, the Tap-1 3' end gene region and the Lmp-7 initial translation codon are separated by an 1182 nucleotide region which contains a TATA-box, a cAMP regulatory element, two SP1 sites, and two G-C-rich regions. Expression of the Lmp-7 messenger RNA was analyzed on different tissues from unstimulated mice. Lmp-7 messenger RNA is expressed in spleen, thymus, lung, liver, heart, and, at a very low level, in kidney but not in brain and testis. The possible role of Lmp genes in antigen processing is discussed.
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460
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Rodriguez M, Prayoonwiwat N, Zhou P, David C. Expression of T cell receptor V beta transcripts in central nervous system of mice susceptible and resistant to Theiler's virus-induced demyelination. J Neuroimmunol 1993; 47:95-100. [PMID: 8376551 DOI: 10.1016/0165-5728(93)90288-a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We utilized the polymerase chain reaction (PCR) to examine for preferential expression of T cell receptor (TcR) V beta s in T cells infiltrating the central nervous system (CNS) of mice infected with Theiler's virus. Infection of susceptible strains of mice with Theiler's virus results in demyelinating disease similar to multiple sclerosis. At 7 days following infection, no difference was observed in TcR V beta usage in lymphocytes infiltrating the CNS between resistant (B10.K) and susceptible (B10.Q or SJL/J) mice. In susceptible mice with prominent demyelination (day 45 and 238 following infection), no preferential expression of TcR V beta s was observed in the CNS. There is strong evidence that T cells play a major role in pathogenesis of TMEV-induced demyelination. There is increasing evidence using recombinant inbred strain mice with TcR V beta deletions that T cells expressing certain TcR V beta genes may be critical in the disease process. Yet, analysis of TcR V beta expression on T cells in CNS using PCR technology did not provide a way to dissect which antigen-specific T cells play a role in disease. These results confirm that during active demyelination specific as well as non-specific T cells are recruited to the CNS. Even though the pathogenesis of TMEV-induced disease may not be identical to that in multiple sclerosis, it is unlikely that similar approaches utilizing polymerase chain reaction will provide insights to the role of T cell receptors in the pathogenesis of multiple sclerosis.
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461
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Wang KA, Zhou P, Rao AM, Eklund PC, Jishi RA, Dresselhaus MS. Intramolecular-vibrational-mode softening in alkali-metal-saturated C70 films. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:3501-3506. [PMID: 10008781 DOI: 10.1103/physrevb.48.3501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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462
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Zhou P, Watson DG, Midgley JM. Identification and quantification of gamma-glutamyl conjugates of biogenic amines in the nervous system of the snail, Helix aspersa, by gas chromatography-negative-ion chemical ionisation mass spectrometry. JOURNAL OF CHROMATOGRAPHY 1993; 617:11-8. [PMID: 8376522 DOI: 10.1016/0378-4347(93)80415-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The gamma-glutamyl conjugates of p-octopamine and dopamine were identified unambiguously for the first time and quantified in a single cerebral ganglion or pleural plus pedal ganglia of the snail, Helix aspersa, by gas chromatography-negative-ion chemical ionisation mass spectrometry. A new method was used for synthesis of gamma-glutamylamine standards. The concentration of gamma-glutamyltyramine was found to be low in the tissues, therefore it was used as an internal standard. The gamma-glutamylamines were extracted with water and derivatised with pentafluoropropionic anhydride and trifluoroethanol. Under negative-ion chemical ionisation conditions, the trifluoroethyl and pentafluoropropionyl derivatives produced significant ions which were sufficiently abundant to be suitable for selective ion monitoring. The method had a limit of detection of ca. 80 pg of gamma-glutamyl conjugate per tissue and calibration curves were linear over the range examined.
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463
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Dong ZH, Zhou P, Holden JM, Eklund PC, Dresselhaus MS, Dresselhaus G. Observation of higher-order Raman modes in C60 films. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:2862-2865. [PMID: 10008701 DOI: 10.1103/physrevb.48.2862] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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464
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Zhou P, Morin BG, Miller JS, Epstein AJ. Magnetization and static scaling of the high-Tc disordered molecular-based magnet V(tetracyanoethylene)x. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:1325-1328. [PMID: 10008005 DOI: 10.1103/physrevb.48.1325] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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465
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Brulet A, Daoud M, Zhou P, Frisch HL. Small angle neutron scattering by interpenetrating polymer networks of poly(carbonate-urethane) and polyvinyl pyridine. ACTA ACUST UNITED AC 1993. [DOI: 10.1051/jp2:1993183] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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466
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Zhou P, Amarasekera J, Solin SA, Mahanti SD, Pinnavaia TJ. Magnetic properties of vermiculite intercalation compounds. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 47:16486-16493. [PMID: 10006083 DOI: 10.1103/physrevb.47.16486] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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467
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Kumar T, Zhou P, Glaser DA. Comparison of human performance with algorithms for estimating fractal dimension of fractional Brownian statistics. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS AND IMAGE SCIENCE 1993; 10:1136-1146. [PMID: 8320584 DOI: 10.1364/josaa.10.001136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Five standard methods for estimating fractal dimension were compared by means of one-dimensional fractional Brownian series generated by four different algorithms yielding series with different statistics. The same one-dimensional series were also displayed as jagged lines and as one-dimensional luminance patterns for judgments by human observers. Only the algorithm implementing the maximum-likelihood method, which required that the generation statistic for the fractal series be known, gave better performance than human observers in estimating fractal dimension. However, when the method of generation is not known, one of the four other standard methods for estimating fractal dimension must be used, and these performed significantly worse than human observers.
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468
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Zhou P, Zanelli E, Smart M, David C. Genomic organization and tissue expression of mouse proteasome gene Lmp-2. Genomics 1993; 16:664-8. [PMID: 8325639 DOI: 10.1006/geno.1993.1245] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The mouse Lmp-2 gene is located within the major histocompatibility complex (MHC) class II region and encodes a subunit of the 20S cytosolic proteasome. Previous studies indicated that the 20S proteasome is a catalytic core of the 26S proteolytic complex that possesses a latent multicatalytic proteinase activity and catalyzes an ATP-dependent, selective breakdown of proteins ligated to ubiquitin. This complex has recently been postulated to be involved in the processing of endogenous antigenic peptides for the MHC class I pathway. Here, we report the genomic organization and tissue expression of the mouse Lmp-2 gene. We have cloned and sequenced the entire mouse Lmp-2 gene, including 5'- and 3'-flanking regions. The gene consists of six exons, and its genomic organization is very similar to that of the recently described human LMP2 gene. Putative promoter and enhancer elements were identified in the 5'-flanking region by sequence comparison with known consensus sequences. The Lmp-2 gene is expressed in most tissues of unstimulated mice, except for brain tissue. The comparison of the 5'-flanking region of human and mouse sequences is discussed.
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469
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Wang ZH, Fung AW, Dresselhaus G, Dresselhaus MS, Wang KA, Zhou P, Eklund PC. Electron-electron interactions and superconducting fluctuations in weakly localized K3C60. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 47:15354-15357. [PMID: 10005925 DOI: 10.1103/physrevb.47.15354] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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470
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Zhou P, Thiele DJ. Copper and gene regulation in yeast. Biofactors 1993; 4:105-15. [PMID: 8347274] [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: 01/30/2023]
Abstract
The essential trace element copper is also highly toxic when accumulated at high intracellular levels. Copper detoxification in the yeasts S.cerevisiae and C.glabrata is carried out, in large part, by small, cysteine-rich metal binding proteins known as metallothioneins (MTs). The biosynthesis of yeast metallothioneins, the S.cerevisiae copper, zinc superoxide dismutase, and presumably other important copper homeostatic proteins, is transcriptionally induced by elevated environmental copper concentrations through the action of copper metalloregulatory transcription factors (MRTFs). Copper coordination drives the formation of a structure distinct from the apo-protein, whereupon the DNA binding function of MRTFs is activated. The copper MRTFs, ACE1 from S.cerevisiae and AMT1 from C.glabrata, directly interact with specific copper-responsive cis-acting elements in the promotor regions of their respective target genes. The binding of copper, as a polynuclear cluster, to MRTFs provides a sensitive and rapid means of transducing the extracellular metal signal to activate gene transcription.
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471
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Olsen NJ, Zhou P, Ong H, Kovacs WJ. Testosterone induces expression of transforming growth factor-beta 1 in the murine thymus. J Steroid Biochem Mol Biol 1993; 45:327-32. [PMID: 8499342 DOI: 10.1016/0960-0760(93)90001-d] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Castration of adult male mice results in enlargement of the thymus and diminution of peripheral suppressor T cell function. Replacement therapy with physiologic doses of androgens reverses these phenomena. Although the mediators involved are unknown, these effects of androgens on the thymus and peripheral immune system are reminiscent of those reported for transforming growth factor-beta (TGF-beta 1). We examined expression of TGF-beta 1 mRNA and bioactive protein in thymuses from castrate and androgen-replaced animals. Steady-state levels of thymic TGF-beta 1 mRNA fell slightly after castration, but rose 2.3-fold after testosterone replacement. Bioactive TGF-beta 1 production by cultured thymic explants also fell following castration to approx. 50% of the levels observed in intact animals. Following 1 week of testosterone replacement in castrate animals, TGF-beta 1 bioactivity produced in culture was restored to levels indistinguishable from those observed with explants from intact animals. Reverse transcription/polymerase chain reaction amplification of RNA revealed that thymocytes are a source of the androgen-modulated TGF-beta 1. These results suggest that TGF-beta 1 may mediate effects of androgens on the immune system.
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472
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Kozopas KM, Yang T, Buchan HL, Zhou P, Craig RW. MCL1, a gene expressed in programmed myeloid cell differentiation, has sequence similarity to BCL2. Proc Natl Acad Sci U S A 1993; 90:3516-20. [PMID: 7682708 PMCID: PMC46331 DOI: 10.1073/pnas.90.8.3516] [Citation(s) in RCA: 746] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
During their lifespan, immature cells normally pass through sequential transitions to a differentiated state and eventually undergo cell death. This progression is aberrant in cancer, although the transition to differentiation can be reestablished in inducible leukemia cell lines. This report describes a gene, MCL1, that we isolated from the ML-1 human myeloid leukemia cell line during phorbol ester-induced differentiation along the monocyte/macrophage pathway. Our results demonstrate that expression of MCL1 increases early in the induction, or "programming," of differentiation in ML-1 (at 1-3 hr), before the appearance of differentiation markers and mature morphology (at 1-3 days). They further show that MCL1 has sequence similarity to BCL2, a gene involved in normal lymphoid development and in lymphomas with the t(14;18) chromosome translocation. MCL1 and BCL2 do not fall into previously known gene families. BCL2 differs from many oncogenes in that it inhibits programmed cell death, promoting viability rather than proliferation; this parallels the association of MCL1 with the programming of differentiation and concomitant maintenance of viability but not proliferation. Thus, in contrast to proliferation-associated genes, expression of MCL1 and BCL2 relates to the programming of differentiation and cell viability/death. The discovery of MCL1 broadens our perspective on an emerging MCL1/BCL2 gene family and will allow further comparison with oncogene families.
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473
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Zhou P, Cao H, Smart M, David C. Molecular basis of genetic polymorphism in major histocompatibility complex-linked proteasome gene (Lmp-2). Proc Natl Acad Sci U S A 1993; 90:2681-4. [PMID: 7681985 PMCID: PMC46159 DOI: 10.1073/pnas.90.7.2681] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Four genes, closely linked to major histocompatibility complex (MHC) class II genes, have been identified in humans, mice, and rats and are thought to be involved in the generation and transport of endogenous immunogenic peptides for the MHC class I antigen-processing pathway. The Tap-1 and Tap-2 genes presumably encode a heterodimeric protein complex responsible for transporting endogenous immunogenic peptides to the lumen of the endoplasmic reticulum. The Lmp-2 and Lmp-7 gene products are two subunits of the large cytosolic proteasome complex possibly involved in generation of endogenous peptides. To study the genetic polymorphism of the Lmp-2 gene, we used a published cDNA sequence as a consensus sequence and PCR-amplified, cloned, and sequenced the Lmp-2 gene from 12 inbred mouse strains. We found three amino acid variants, LMP-2d, LMP-2b, and LMP-2q, which partially correlated with restriction fragment length polymorphism variants identified with Southern blots. Allelic polymorphism of the Lmp-2 gene may be involved in peptide selection, leading to autoimmune disease susceptibility.
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474
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Tian X, Xu Y, Ma Y, Zhou P. [Purification and properties of beta-mannanases from alkalophilic Bacillus N16-5]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1993; 33:115-21. [PMID: 8356831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Three extracellular alkaline beta-mannanases from an alkalophilic Bacillus N16-5 were purified to electrophoretic homogeneity by (NH4)2SO4 precipitation, DEAE-Sephadex A-25 chromatography, hydroxyapatite chromatography and preparative electrophoresis. Molecular weights and pI values of the beta-mannanases (M-1, M-2 and M-3) were 51000, 38000 and 34700 by SDS-PAGE and 4.3, 2.5 and 2.5 by PAGEIEF, respectively. The optimum pH for enzyme catalysis were 9.0 for M-1 and 10.0 for M-2 and M-3, respectively. All of three enzymes were the most active at 70 degrees C. The activities of three enzymes were strongly inhibited by Ag1+, Hg2+ and Mn2+. Michaelis constants (Km) of the enzyme M-1, M-2 and M-3 for mannase from konjak were 2.9, 1.7 and 12.5 mg/ml, maximum velocities (Vmax) for the saccharide were 27500, 47500 and 15700 mumol.min-1.mg-1, respectively. Konjak was hydrolyzed by the enzyme M-1, and major components in digests were mono-, di-, tri- and tetra-saccharides.
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475
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Rao AM, Zhou P, Wang KA, Hager GT, Holden JM, Wang Y, Lee WT, Bi XX, Eklund PC, Cornett DS, Duncan MA, Amster IJ. Photoinduced Polymerization of Solid C60 Films. Science 1993. [DOI: 10.1126/science.259.5097.955] [Citation(s) in RCA: 1004] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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476
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McCammon DK, Zhou P, Turney MK, McPhaul MJ, Kovacs WJ. An androgenic affinity ligand covalently binds to cytosolic aldehyde dehydrogenase from human genital skin fibroblasts. Mol Cell Endocrinol 1993; 91:177-83. [PMID: 8472848 DOI: 10.1016/0303-7207(93)90270-t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A 56 kDa protein expressed in human genital skin fibroblasts was first identified by independent laboratories on the basis of its specific expression in androgen target cells and its ability to covalently bind androgenic affinity ligands. Recently, immunoscreening of a cDNA library with antisera directed against this protein resulted in the isolation of a partial cDNA clone identical to human cytosolic aldehyde dehydrogenase (ALDH1). We report here the preparation of a full-length cDNA encoding ALDH1 from human genital fibroblasts. Translation of the encoded protein in a cell-free system yields a 56 kDa product that can be covalently radiolabeled with [3H]dihydrotestosterone 17 beta-bromoacetate (DHT-BA). Expression of the full-length clone in mammalian cells also results in expression of a 56 kDa DHT-BA binding protein. The covalent binding of DHT-BA by ALDH1 is an intrinsic property of the enzyme and is not dependent on androgen receptor expression.
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477
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Khoo IC, Zhou P. Nonlinear interface tunnelingphase shift. OPTICS LETTERS 1992; 17:1325. [PMID: 19798170 DOI: 10.1364/ol.17.001325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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478
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Cheng J, Zhou P. Integrable surface-emitting laser-based optical switches and logic gates for parallel digital optical computing. APPLIED OPTICS 1992; 31:5592-5603. [PMID: 20733743 DOI: 10.1364/ao.31.005592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We describe the recent advances in a monolithic optoelectronic technology based on the integration of two-dimensional arrays of cascadable optical switches and optical logic gates consisting of vertical-cavity surface-emitting lasers (VCSEL's) and heterojunction phototransistors or photothyristors. Different combinations of these components can perform optical switching, logic, memory, and regeneration. Latching, nonlatching, and bistable switches with high optical gain and contrast are demonstrated by using a single GaAs-AlGaAs epilayer design along with single-stage Boolean optical logic functions: AND, OR, IDENTITY, INVERT, NAND, NOR, and XOR. As an application to parallel, digital arithmetic logic, we describe a simple, compact, two-chip binary adder, which uses optical symbolic substitution and two-dimensional VCSEL-PNPN logic gate arrays.
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479
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Zhou P, Szczypka MS, Sosinowski T, Thiele DJ. Expression of a yeast metallothionein gene family is activated by a single metalloregulatory transcription factor. Mol Cell Biol 1992; 12:3766-75. [PMID: 1508182 PMCID: PMC360240 DOI: 10.1128/mcb.12.9.3766-3775.1992] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The opportunistic pathogenic yeast Candida glabrata elicits at least two major responses in the presence of high environmental metal levels: transcriptional induction of the metallothionein gene family by copper and the appearance of small (gamma-Glu-Cys)nGly peptides in the presence of cadmium. On the basis of a trans-activation selection scheme in the baker's yeast Saccharomyces cerevisiae, we previously isolated a C. glabrata gene which encodes a copper-activated DNA-binding protein designated AMT1. AMT1 forms multiple specific DNA-protein complexes with both C. glabrata MT-I and MT-IIa promoter DNA fragments. In this report, we localize and define the AMT1-binding sites in the MT-I and MT-IIa promoters and characterize the mode of AMT1 binding. Furthermore, we demonstrate that the AMT1 protein trans activates both the MT-I and MT-IIa genes in vivo in response to copper and that this activation is essential for high-level copper resistance in C. glabrata. Although AMT1-mediated trans activation of the C. glabrata metallothionein genes is essential for copper resistance, AMT1 is completely dispensable for cadmium tolerance. The distinct function that metallothionein genes have in copper but not cadmium detoxification in C. glabrata is in contrast to the role that metallothionein genes play in tolerance to multiple metals in higher organisms.
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480
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Peng J, Li G, Zhou P. Phase properties and atomic coherent trapping in the system of a three-level atom interacting with a bimodal field. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 46:1516-1521. [PMID: 9908273 DOI: 10.1103/physreva.46.1516] [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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481
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Rogan MT, Craig PS, Zehyle E, Masinde G, Wen H, Zhou P. In vitro killing of taeniid oncospheres, mediated by human sera from hydatid endemic areas. Acta Trop 1992; 51:291-6. [PMID: 1359755 DOI: 10.1016/0001-706x(92)90047-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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482
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Zhou P, Wang KA, Wang Y, Eklund PC, Dresselhaus MS, Dresselhaus G, Jishi RA. Raman scattering in C60 and alkali-metal-saturated C60. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:2595-2605. [PMID: 10003939 DOI: 10.1103/physrevb.46.2595] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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483
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Zhou P, Drumheller JE, Patyal B, Willett RD. Magnetic properties and critical behavior of quasi-two-dimensional systems. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:12365-12376. [PMID: 10001274 DOI: 10.1103/physrevb.45.12365] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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484
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Zhou P, Wang KA, Rao AM, Eklund PC, Dresselhaus G, Dresselhaus MS. Raman-scattering studies of homogeneous K3C60 films. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:10838-10840. [PMID: 10001003 DOI: 10.1103/physrevb.45.10838] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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485
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Xue KX, Ma GJ, Wang S, Zhou P. The in vivo micronucleus test in human capillary blood lymphocytes: methodological studies and effect of ageing. Mutat Res 1992; 278:259-64. [PMID: 1373862 DOI: 10.1016/s0165-1218(10)80005-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The in vivo micronucleus test in lymphocytes of human capillary blood collected by skin puncture is described. This method needs only 1-2 drops of finger blood. The normal value of micronucleus frequencies in lymphocytes from 250 healthy persons aged 6-88 years was determined. The upper limits of normal values were estimated by means of percentile. The 95th percentiles were 1/1000 and 1.5/1000 for the 6-45-year age group and the 46-88-year age group, respectively. There was no significant difference in micronucleus frequency between men and women. On the basis of micronucleus assays in more than 3000 cases, we consider that the micronucleus test in human capillary blood lymphocytes is a rapid, convenient and sensitive procedure for monitoring a human population exposed to environmental and occupational mutagens and carcinogens.
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486
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Allan JC, Craig PS, Garcia Noval J, Mencos F, Liu D, Wang Y, Wen H, Zhou P, Stringer R, Rogan M. Coproantigen detection for immunodiagnosis of echinococcosis and taeniasis in dogs and humans. Parasitology 1992; 104 ( Pt 2):347-56. [PMID: 1594298 DOI: 10.1017/s0031182000061801] [Citation(s) in RCA: 149] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Three ELISA assays, based on hyperimmune rabbit serum raised against adult cestode somatic antigen, were applied in this study for the detection of Taenia- and Echinococcus-specific antigens in host faeces. The first assay, using an antiserum against Taenia pisiformis antigen extract, was used in a time-course of T. pisiformis experimental infection in dogs. The assay was shown to be considerably more sensitive than microscopical detection of eggs in faeces. Antigen was present in faeces before patency and antigen levels were independent of T. pisiformis egg output. The second assay, involving a test for human taeniasis based on antibodies against T. solium, was applied in two field studies carried out in China and Guatemala. The test was highly specific, no false positive reactions occurred with human faecal samples and the test was capable of diagnosing individuals who would not have been detected by coproscopy or treatment to recover the tapeworm. A third assay was designed for E. granulosus and demonstrated 87.5% sensitivity and 96.5% specificity with samples from naturally and experimentally infected dogs with Echinococcus or Taenia infections. In both the human Taenia and canine Echinococcus studies antigen could be detected in faecal samples from infected hosts stored in 5% formalin for 6 months. Further refinements to these tests for field application are discussed.
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487
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Hamadeh RM, Jarvis GA, Galili U, Mandrell RE, Zhou P, Griffiss JM. Human natural anti-Gal IgG regulates alternative complement pathway activation on bacterial surfaces. J Clin Invest 1992; 89:1223-35. [PMID: 1556184 PMCID: PMC442982 DOI: 10.1172/jci115706] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
One percent of circulating IgG in humans recognizes galactose alpha 1,3 galactose residues (anti-Gal) and is synthesized in response to stimulation by enteric bacteria. In this study, we found that the prevalence of binding of anti-Gal to blood isolates is significantly higher than its binding to normal stool isolates. When anti-Gal bound onto the lipopolysaccharide of a representative blood isolate, Serratia marcescens #21, it blocked its alternative complement pathway (ACP) lysis and made the organism serum resistant. In contrast, when anti-Gal bound to the capsular polysaccharide of a serum sensitive Serratia, #7, it increased ACP killing of this strain. The mechanism of blockade of ACP lysis by anti-Gal did not involve a decrease in the number of C3 molecules deposited onto Serratia #21 or an inhibition of the binding of C3b to its LPS, nor did it change the iC3b and C3d degradation products of bound C3b or prevent membrane attack complex formation on this organism. Our findings suggest that the effect of anti-Gal on immune lysis is dependent on the bacterial outer membrane structure to which it binds. We postulate that anti-Gal may play a role in the survival of selected Enterobacteriacae in Gram-negative sepsis by blocking ACP-mediated lysis of such bacteria by the nonimmune host, and that this effect depends on where anti-Gal finds its epitope on the bacterial outer membrane.
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488
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Xue KX, Wang S, Ma GJ, Zhou P, Wu PQ, Zhang RF, Xu Z, Chen WS, Wang YQ. Micronucleus formation in peripheral-blood lymphocytes from smokers and the influence of alcohol- and tea-drinking habits. Int J Cancer 1992; 50:702-5. [PMID: 1544703 DOI: 10.1002/ijc.2910500506] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In recent years, studies on the genotoxic effects of smoking and its modifying factors have been widely followed with interest. In this report, frequencies of micronuclei (MNF) in peripheral-blood lymphocytes in 220 healthy smokers have been detected by the micronucleus test by finger-skin puncture, which needs only 1 to 2 drops of peripheral blood. On the basis of analysis of matched-pair data, the modifying effects of alcohol and tea are discussed. Our results show that (I) smoking significantly increases MNF in lymphocytes as compared with healthy non-smokers (p less than 0.01); (2) alcohol significantly increases MNF in smokers (p less than 0.01); (3) tea decreases MNF induced by smoking (p less than 0.01). Therefore, the anti-carcinogenic role of tea merits further study.
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489
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Zhou P, Smart MK, Cheng S, Savarirayan S, Inoko H, David CS. HLA-DQ beta chain can present mouse endogenous provirus MTV-9 product and clonally delete Tcr V beta 5+ and V beta 11+ T cells in transgenic mice. Immunogenetics 1992; 35:219-23. [PMID: 1311702 DOI: 10.1007/bf00166826] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The elusive Mls gene(s) are mouse mammary tumor virus genes. The endogenous cotolerogen involved in the clonal deletion of Tcr V beta 5.1, 5.2, and 11 in H-2E+ mouse strains has been narrowed down to MTV-9. We demonstrate that similar to H-2E alpha molecules, human DQw6 beta chain mediated clonal deletion of Tcr V beta 5.1, 5.2, and 11 also requires the MTV-9 gene product. This shows that human class II molecules can present mouse retroviral antigen. Further, backcross analysis involving [B10.M(DQb) x DBA/1] suggest a second cotolerogen in the B10.M background in the clonal deletion of V beta 5-bearing T cells.
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490
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Zhou P, Tuthill GF, Drumheller JE. Intermediate phase in the anisotropic Heisenberg quasi-two-dimensional antiferromagnet. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:2541-2544. [PMID: 10001792 DOI: 10.1103/physrevb.45.2541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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491
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Wang KA, Wang Y, Zhou P, Holden JM, Ren S, Hager GT, Ni HF, Eklund PC, Dresselhaus G, Dresselhaus MS. Raman scattering in C60 and alkali-metal-doped C60 films. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:1955-1958. [PMID: 10001707 DOI: 10.1103/physrevb.45.1955] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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492
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Spivey J, Srivastave RD, Zhou P, Stiegel GJ, Rao VUS, Cinquegrane G. Direct conversion of methane to liquid fuels and chemicals. CATALYSIS 1992. [DOI: 10.1039/9781847553218-00183] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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493
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Watson DG, McGhee CN, Midgley JM, Zhou P, Doig WM. Determination of acidic metabolites of biogenic amines in human aqueous humour by gas chromatography--negative ion chemical ionisation mass spectrometry. J Neurochem 1992; 58:116-20. [PMID: 1727423 DOI: 10.1111/j.1471-4159.1992.tb09285.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The concentrations of acidic metabolites derived from the biogenic amines o-, m-, and p-tyramines (o-, m-, and p-hydroxyphenylacetic acids), p-octopamine/p-synephrine (p-hydroxymandelic acid), and dopamine (homovanillic acid and 3,4-dihydroxyphenylacetic acid) were measured in human aqueous humour obtained from patients undergoing elective surgery for cataract removal or for trabeculectomy as a treatment for chronic open-angle glaucoma. There were no clear differences in the pattern of metabolism of neurotransmitters between the two groups. An unexpected finding was that the o-tyramine metabolite, o-hydroxyphenylacetic acid, was present in aqueous humour.
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494
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Zhou P, Mocek U, Siesel B, Floss HG. Biosynthesis of pyrrolnitrin. Incorporation of 13C, 15N double-labelled D- and L-tryptophan. J Basic Microbiol 1992; 32:209-14. [PMID: 1512712 DOI: 10.1002/jobm.3620320312] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Experiments on the incorporation of D- and L-[alanine-3-13C,2-15N]tryptophan into the antibiotic pyrrolnitrin in Pseudomonas aureofaciens confirmed earlier conclusions about the conversion of L-tryptophan into pyrrolnitrin. They also demonstrated that a fraction of the D isomer is incorporated without breakage of the 15N-carbon bond, consistent with the operation of a second pathway from D-tryptophan to pyrrolnitrin. Cell-free experiments confirmed the conversion of 3-(o-aminophenyl)pyrrole into aminopyrrolnitrin but failed to detect enzymatic oxidation of the latter to pyrrolnitrin.
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495
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Craig RW, Kozopas KM, Yang T, Buchan HL, Zhou P. 17. Characterization of mcl-1, a gene expressed in the early stages of myeloid leukemia cell differentiation. Pharmacotherapy 1992. [DOI: 10.1016/0753-3322(92)90102-d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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496
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Cunningham RK, Zhou P, Zaleski MB. Postnatal development of murine spleen cell proliferative responses induced by interleukin 2 or phorbol ester and calcium ionophore A23187. Immunobiology 1991; 184:53-62. [PMID: 1800311 DOI: 10.1016/s0171-2985(11)80571-1] [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: 12/28/2022]
Abstract
To determine the kinetics of the ontogeny of polygenically controlled proliferative responses, spleen cells from 5, 10 and 20 day-old mice, previously identified as high (B10.PL-Thy-1a, AKR.M) and low (C3H.A) responders were tested. Cells (10(5)) were simulated in vitro with human recombinant IL-2 (35 U), a mixture of either IL-2 (0.7 U) and 13-myristate 12-acetate phorbol (5 ng) or phorbol and calcium ionophore A23187 (5 ng). Two parameters were assessed; proliferation measured by 3H-thymidine incorporation and the synergistic effect expressed as a synergism coefficient (SC): the ratio of proliferation induced by a mixture to the sum of proliferations induced by each component alone. At the age of 5 days, all three strains, regardless of stimulation, produced similar proliferation and showed no synergistic effect (SC = 1.0). At the age of 10 days, proliferation of high responder cells was 3-5 times higher than that of the low responder, but only high responders displayed marginal synergistic effect (2 greater than SC greater than 1.5). At the age of 20 days, proliferative responses of the high responders increased somewhat and a definitive synergistic effect became clearly demonstrable (SC greater than 3.0). This effect increased further after the age of 20 days to reach the level of SC greater than 5.0 in adult high responders. The delay in expression of synergistic effect was due to a substantial proliferation induced by phorbol alone in 10 day-old animals. The available data allow the conclusion that phenotypic strain variation in proliferative responses is first detectable at the age of 10 days and becomes fully developed only after attaining the age of 20 days or more. Since the magnitude of proliferative responses was not associated with frequencies of IL-2R alpha + cells it seems that differences in responsiveness can not be attributed to the induction of IL-2R alpha chain, and they may reflect intrinsic abilities of cells to proliferate.
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497
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Zhou P, Peng JS. Dipole squeezing in the two-photon Jaynes-Cummings model with superposition state preparation. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 44:3331-3335. [PMID: 9906334 DOI: 10.1103/physreva.44.3331] [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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498
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Zhou P, Anderson GD, Savarirayan S, Inoko H, David CS. Human HLA-DQ beta chain presents minor lymphocyte stimulating locus gene products and clonally deletes TCR V beta 6+, V beta 8.1+ T cells in single transgenic mice. Hum Immunol 1991; 31:47-56. [PMID: 1908840 DOI: 10.1016/0198-8859(91)90048-e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Minor lymphocyte stimulating locus (Mls) gene products in association with mouse major histocompatibility complex (MHC) class II molecules are known to determine the repertoire of T-cell receptor (TCR) in mature T cells. In order to test whether human class II molecules can present mouse Mls, HLA-DQ beta transgenic mice were generated. The expression and function of the DQ beta transgene were studied in the progeny of one selected founder which was H-2f and H-2E negative. In these mice, DQ beta molecules pairing with mouse A alpha chain and invariant chain are expressed on the cell surface in a tissue-specific manner. When the DQ beta gene was bred into the Mls-1a strain DBA/1 (H-2q), T cells bearing V beta 6 and V beta 8.1 TCR were clonally deleted in the thymus of DQ beta+ transgenics but not in DQ beta-negative full sibs. Thus, the data presented here clearly demonstrate that the human MHC DQ beta chain can present Mls in the clonal deletion of T cells. Our results also suggest the requirement for an interaction between CD4 and class II molecules (alpha chain) for clonal deletion of T cells to occur.
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499
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Tao P, Zhang T, Zhou P, Wang S, Cheng S, Jiang J. The inhibition effects of catechin derivatives on the activities of human immunodeficiency virus reverse transcriptase and DNA polymerases. Antiviral Res 1991. [DOI: 10.1016/0166-3542(91)90135-e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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500
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Zhou P, Savarirayan S, Anderson G, Inoko H, David CS. Alteration of mouse T-cell receptor repertoire by Aa/DQb hybrid molecules in human HLA-DQb single transgenic mice. Transplant Proc 1991; 23:423-6. [PMID: 1899308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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