976
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Li Z, Xu X, Khoo SB, Mok KF, Hor TSA. Formation and structural relationship of electroactive PtII–HgII polymetallic sulfide aggregates. ACTA ACUST UNITED AC 2000. [DOI: 10.1039/b003799k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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977
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Li Z, Loh ZH, Audi Fong SW, Yan YK, Henderson W, Mok KF, Hor TSA. Ligand-stabilization of an unusual square-based pyramidal geometry of Cd(II) and Zn(II) in an heterometallic {MPt2S2} core (M = Cd, Zn). ACTA ACUST UNITED AC 2000. [DOI: 10.1039/a909254d] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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978
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Li ZH, Liu DP, Liang CC. Modified inverse PCR method for cloning the flanking sequences from human cell pools. Biotechniques 1999; 27:660-2. [PMID: 10524300 DOI: 10.2144/99274bm05] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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979
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Chen RS, Liu YX, Liu CB, Hu YS, Xu DC, Zhong SZ, Li ZH. Anatomic basis of iliac crest flap pedicled on the iliolumbar artery. Surg Radiol Anat 1999; 21:103-7. [PMID: 10399209 DOI: 10.1007/s00276-999-0103-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
This paper presents the anatomy and clinical applications of an iliac crest flap pedicled on the iliolumbar artery. 54 iliolumbar arteries were filled with pink plastic in 27 adult cadavers. Their origin, course and branches, and the surroundings were investigated, and the external diameter, length of segments and terminal distribution were measured. The iliolumbar artery was constant, but with a few variations. Its length was 7.0 +/- 3.9 cm, and the outer diameter 2.0 +/- 0.4 mm at the lateral edge of the psoas major muscle. Based on the anatomic findings, the surgical technique for a bone flap based on the iliolumbar artery was designed. Its clinical applications included both free bone grafting (in 2 patients) and pedicled bone transfer (in another 2 patients). The clinical results were satisfactory. The iliac crest flap pedicled on the iliolumbar artery is a reliable bone flap for clinical usage.
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980
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Zhang WG, Liu XF, Wang Y, Jian X, Lin Q, Chen A, Wu CW, Huang HM, Li ZH, Zhang Y, Huang HL. [Construction of expressing vector for phage display scFv and a mouse unspecified antibody library]. YI CHUAN XUE BAO = ACTA GENETICA SINICA 1999; 26:99-106. [PMID: 10375858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The display of antibody gene library on the surface of E. coli filamentous phage offers a new method of obtaining antibodies against specific antigens. In the paper, it is reported that a phagemid for phage display antibody, named after pFUW80, characterized expressing scFv either secretly or stickily. With a series of designed PCR primers, heavy-chain and light-chain variable region genes of mice antibodies were amplified and a mouse unspecified single-chain antibody library with the size of 1.2 x 10(6) clones was constructed. From this library, phage was selected out against antigen human IgG and detected by ELISA and partial sequence analysis. These primary results established the foundation for future research using this system.
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981
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Li ZH, Carraro R, Gregerman RI, Lau DC. Adipocyte differentiation factor (ADF): a protein secreted by mature fat cells that induces preadipocyte differentiation in culture. Cell Biol Int 1999; 22:253-70. [PMID: 10101042 DOI: 10.1006/cbir.1998.0237] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A factor that is released into the culture medium of mature adipocytes and promotes the differentiation (adipogenic conversion) of preadipocytes has been partially characterized. The factor acts in a dose-dependent manner on preadipocytes to produce up to a four-fold increase in triacylglycerol (triglyceride) content and a nine-fold increase in glycerol-3-phosphate dehydrogenase (GPDH) activity, a marker of the late phase of differentiation of preadipocytes. The material appears to be a protein, since it has a molecular weight (Superose-12 gel exclusion chromatography) of about 53 kDa, an isoelectric point (pl) of 4.7-4.9, and is inactivated by the proteases papain and chymotrypsin and extremes of pH (2 and 12). Considerations of molecular weight, isoelectric point, stability to specific proteases, and especially to the action of chemical agents [the adipogenic activity is not affected by either an oxidizing (KIO4) or a reducing agent (DTT)], lead to the conclusion that the differentiation factor is distinct from known cytokines. The authors suggest that the protein be designated adipocyte differentiation factor (ADF). ADF in vivo may act as a cytokine paracrine agent to regulate the differentiation of preadipocytes.
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982
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Hatton GI, Li ZH. Neurophysiology of magnocellular neuroendocrine cells: recent advances. PROGRESS IN BRAIN RESEARCH 1999; 119:77-99. [PMID: 10074782 DOI: 10.1016/s0079-6123(08)61563-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Magnocellular neuroendocrine cells of the hypothalamic paraventricular and supraoptic nuclei are responsible for most of the vasopressin and oxytocin in the peripheral blood as well as for central release of these peptides in selected brain areas. As the principal component of the hypothalamo-neurohypophysial system, these neurons have been a subject of continual study for half a century. The wealth of solid information from decades of in vivo studies has provided a firm basis for in vitro, brain slice and explant investigations of neural mechanisms involved in the control and regulation of vasopressin and oxytocin neurons. In vitro methods have revealed the presence and permitted the study of monosynaptic projections to supraoptic neurons from the olfactory bulbs, the tuberomammillary nuclei of the posterior hypothalamus and from the organum vasculosum of the lamina terminalis. Such methods have also facilitated the elucidation of the various ionic currents controlling neurosecretory cell activity as well as the roles of calcium binding proteins and release of calcium from internal stores. This review summarizes recent advances in our understanding of the afferent inputs that impinge upon these two cell types, and the cellular and molecular mechanisms intrinsic to these neurons that determine their activity patterns and, in part, their responses to incoming stimuli.
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983
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Li ZH, Jin HL, Zhu JZ. [Observation of repair of wounded rat skin by affinity histochemical method of SJA]. FA YI XUE ZA ZHI 1999; 15:1-2, 4, 62. [PMID: 12536384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Time expression of SJA tissue receptors surrounding wounded skin of 40 rats was studied by affinity histochemical method. The results were compared to that by EGFR immunohistochemical method and c-myc situ hydridization method. It was observed that SJA receptors began to decrease after the skin was injured and reached the lowest quantities in 15 minutes. After that, they began to increase and reached the highest quantities in 2 hours. It needs to be further studied whether there is the correlation between SJA receptors and EGFR has the function of repairing wounded skin.
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984
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Li ZH, Liu DP, Wang J, Guo ZC, Yin WX, Liang CC. Inversion and transposition of Tc1 transposon of C. elegans in mammalian cells. SOMATIC CELL AND MOLECULAR GENETICS 1998; 24:363-9. [PMID: 10763415 DOI: 10.1023/a:1024494508878] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Tc1/mariner transposons are widespread in the eukaryotes. In vitro transposition test indicated that the transposase is the only protein that is needed in transpositions. It was shown later that the reconstructed Tc1-like transposon, "sleeping beauty" in fish, and the Tc1 transposon in C. elegans jumps in human cells. This discovery indicates that the Tc1/mariner transposon may be engineered as a somatic gene therapy vector if coupled with an efficient gene delivery system. We introduced the Tc1 transposon from C. elegans into different mammalian cell lines and detected the transposition events, indicating that Tc1 transposon functions in different mammalian cells. Interestingly, a high inversion frequency of the transposon was also detected, suggesting that this type of transposon may add variations to host genome when it is horizontally transferred into a new species.
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985
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Li L, Xie N, Li ZH. [The absolute configurations and biological activities of alpha- and beta-anordrins]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1998; 31:554-7. [PMID: 9772699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The molecular structures and absolute configurations of alpha- and beta-anordrins are reported. Animal experiments showed that pure alpha-epimer possessed high anti-implantation and anti-early pregnancy effects, but the pure beta-epimer exhibited very low effects at the same dose. MNDO program was applied for the optimization of the configurations of epimers to establish the isolated molecular configurations and calculate the quantum chemical indexes. The results showed that the configurations and the differences of action field in three-dimensions of alpha- and beta-epimer are probably the factors that the alpha-epimer exhibited biological activity.
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986
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Tsao JL, Zhang J, Salovaara R, Li ZH, Järvinen HJ, Mecklin JP, Aaltonen LA, Shibata D. Tracing cell fates in human colorectal tumors from somatic microsatellite mutations: evidence of adenomas with stem cell architecture. THE AMERICAN JOURNAL OF PATHOLOGY 1998; 153:1189-200. [PMID: 9777950 PMCID: PMC1853055 DOI: 10.1016/s0002-9440(10)65663-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Occult aspects of tumor proliferation are likely recorded genetically as their microsatellite (MS) loci become polymorphic. However, MS mutations generated by division may also be eliminated with death as noncoding MS loci lack selective value. Therefore, highly polymorphic MS loci cannot exist unless mutation rates are high, or unless mutation losses are inherently minimized. Mutations accumulate differently when cell fates are determined intrinsically before or extrinsically after division. Stem cell (asymmetrical division as in intestinal crypts) and random (asymmetrical and symmetrical division) proliferation, respectively, represent simulated cell fates determined before or after division. Whereas mutations regardless of selection systematically persist once inherited with stem cell proliferation, mutations are eliminated by the symmetrical losses of both daughter cells with random proliferation. Therefore, greater genetic diversity or MS variance accumulate with stem cell compared with random proliferation. MS loci in normal murine intestinal mucosa and xenografts of cancer cell lines accumulated mutations, respectively, consistent with stem cell and random proliferation. Tumors from patients with hereditary nonpolyposis colorectal cancer (HNPCC) demonstrated polymorphic MS loci. Overall, three of five adenomas and one of six cancers exhibited high MS variances. Assuming mutation rates are not significantly greater in adenomas than in cancers, these studies suggest the stem cell proliferation and hierarchy of normal intestines persists in many HNPCC adenomas and some cancers. An adenoma stem cell architecture can explain the complex polymorphic MS loci observed in HNPCC adenomas and account for many adenoma features. In contrast, cancers may lose intrinsic control of cell fate. These studies illustrate a feasible phylogenetic approach to unravel and describe occult aspects of human tumor proliferation. The switch from predominantly stem cell to random proliferation may be a critical and defining characteristic of malignancy.
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987
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Shiraki K, Sato H, Yamamura J, Li ZH, Yokoyama T, Hasegawa T, Okuno T, Kurokawa M, Kageyama S. Functions of purified gB, gE:gI, and gH:gL, and their sialyl residues in varicella-zoster virus infection. Arch Virol 1998; 142:2295-301. [PMID: 9672594 DOI: 10.1007/s007050050243] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Varicella-zoster virus glycoproteins were purified by using monoclonal antibodies and analyzed for their effects on cell-free virus infection. Preinfection treatment of cells with gH:gL reduced the infection efficiency and increased the number of unadsorbed virus. Postinfection treatment of cells with gB increased the infection efficiency, but that with gE:gI reduced it. Treatment of gE:gI and gH:gL with neuraminidase (NA) abolished their inhibitory activity and the plaque formation was enhanced by NA treatment of glycoproteins and cells. Glycoproteins exhibited their diverse activities despite their common role in viral penetration, and sialyl residues were responsible for their function in cell-free virus infection.
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988
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Ge Y, Li ZH, Marshall MS, Broxmeyer HE, Lu L. Involvement of H-ras in erythroid differentiation of TF1 and human umbilical cord blood CD34 cells. Blood Cells Mol Dis 1998; 24:124-36; discussion 137. [PMID: 9628849 DOI: 10.1006/bcmd.1998.0179] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the role of the ras gene in erythroid differentiation, a human erythroleukemic cell line, TF1, was transduced with a selectable retroviral vector carrying a mammalian wild type H-ras gene or a cytoplasmic dominant negative RAS1 gene. Transduction of TF1 cells with the wild type H-ras gene resulted in changes of cell types and up-regulation of erythroid-specific gene expression similar to that seen in differentiating erythroid cells. The number of red blood cell containing colonies derived from TF1 cells transduced with wild type H-ras cDNA was significantly increased and the cells in the colonies were more hemoglobinized as estimated by a deeper red color compared to those colony cells from mock or dominant negative RAS1 gene transduced TF1 cells, suggesting increased erythroid differentiation of TF1 cells after transduction of wild type H-ras in vitro. The mRNA levels of beta- and gamma-, but not alpha-, globin genes were significantly higher in H-ras transduced TF1 cells than those in TF1 cells transduced with mock or dominant negative RAS1 gene. Moreover, a 4kb pre-mRNA of the Erythropoietin receptor (EpoR) was highly expressed only in H-ras transduced TF1 cells. Additionally, human umbilical cord blood (CB) CD34 cells which are highly enriched for hematopoietic stem/progenitor cells were transduced with the same retroviral vectors to evaluate in normal primary cells the activities of H-ras in erythroid differentiation. Increased numbers of erythroid cell containing colonies (BFU-E and CFU-GEMM) were observed in CD34 cells transduced with the H-ras cDNA, compared to that from mock transduced cells. These data suggest a possible role for ras in erythroid differentiation.
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989
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Shiraki K, Yamamura J, Kurokawa M, Andoh T, Sato H, Yoshida Y, Li ZH, Kamiyama T, Kageyama S. A live non-neurovirulent herpes simplex virus vector expresses beta-galactosidase in the nervous system of the Wistar and Sprague-Dawley strain rat for a prolonged period. Neurosci Lett 1998; 245:69-72. [PMID: 9605487 DOI: 10.1016/s0304-3940(98)00183-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have constructed a live non-neurovirulent herpes simplex virus vector expressing beta-galactosidase under the control of the latency associated transcript promoter without inducing inflammation. Pathogenicity of the recombinant virus (betaH1) was not observed in the cutaneous, intravenous and intracerebral infection in mice. When betaH1 was inoculated at the caudate putamen of rats, beta-galactosidase activity was observed in neurons at the inoculation site and its projecting frontal cortex. Expression of beta-galactosidase was observed in the neurons of the innervating dorsal root ganglia 45 days after inoculation of betaH1 into the hind paws of the rats. Neither inflammation nor tissue destruction was observed in both neural tissues in this study. Thus this non-neurovirulent recombinant virus is a suitable vector for expressing the foreign genes in the nervous system for the prolonged period.
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990
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Lu L, Li ZH, He J, Ge Y, Rice S, Broxmeyer HE. Transduction of recombinant human erythropoietin receptor cDNA into daughter progenitors derived from single CD34(3+) cord blood cells changes the differentiation profile of daughter progenitors. J Leukoc Biol 1998; 63:389-94. [PMID: 9500528 DOI: 10.1002/jlb.63.3.389] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In this study, we tested the capacity to change the differentiation profile of progenitor cells by retroviral-mediated transduction of EpoR cDNA into one of the paired daughter cells derived from single CD34(3+) CB cells. Our results show that for the non-viral-treated daughter cells, the majority (99.6%) formed the same colony type. However, with cells transduced with viral vectors, 7.1% of the daughter cells transduced with the EpoR cDNA formed either a burst forming unit-erythroid (BFU-E) or a colony-forming unit-granulocyte, macrophage, erythroid, megakaryocyte (CFU-GEMM) colony compared to the other daughter cell transduced with viral supernatant lacking EpoR cDNA, which formed either a colony-forming unit granulocyte-macrophage (CFU-GM) or a high proliferative potential-colony forming cell (HPP-CFC) colony. Expression of the transduced EpoR cDNA was confirmed in individual colonies by RT-PCR analysis. These results substantiate in a more rigorous fashion our previous results that it is possible to change the Epo-responsive differentiation profile of progenitor cells by transduction into these cells of an EpoR cDNA and this change was apparent only in daughter cells derived from single CD34(3+) kit+ cells transduced with EpoR cDNA.
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991
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Kim DH, Li ZH, Lee SS, Park J, Chung SJ. A novel type of structurally simple nonpeptide inhibitors for alpha-chymotrypsin. Induced-fit binding of methyl 2-allyl-3-benzenepropanoate to the S2 subsite pocket. Bioorg Med Chem 1998; 6:239-49. [PMID: 9547947 DOI: 10.1016/s0968-0896(97)10038-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Unexpectedly, methyl and benzyl esters of 2-allyl-3-benzenepropanoic acid were found to be not substrates but potent competitive inhibitors for alpha-chymotrypsin. The inhibitory property of the structurally simple nonpeptidic compounds is ascribed to their high binding affinity to the enzyme at the S2 rather than S1 subsite pocket. These inhibitors exist in a flexible form in solution, but as they bind to the enzyme bulky contrained conformers present in a minute concentration play an important role, forming tighter enzyme.inhibitor complexes by binding to the large hydrophobic S2 pocket. The contrained conformers are thought to be resulted from intramolecular CH/pi interactions between a vinylic proton and the aromatic pi-electron cloud in the inhibitor molecules. These compounds constitute novel examples of the induced-fit binding inhibitor of possibly simplest structure.
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992
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993
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Li ZH, Zhu YJ, Lit XT. Wild-type p53 gene increases MDR1 gene expression but decreases drug resistance in an MDR cell line KBV200. Cancer Lett 1997; 119:177-84. [PMID: 9570369 DOI: 10.1016/s0304-3835(97)00267-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Inactivation of p53 gene and overexpression of MDR1 gene are both associated with drug resistance. Previous studies have suggested that p53 gene can modulate the expression activity of MDR1 gene promoter in a promoter-CAT system. In the present study, wild-type p53 gene cDNA was introduced into a multidrug-resistant cell line, KBv200, in which endogenous p53 gene is aberrant. In wt-p53 transfected cells, the expression of MDRI gene was significantly increased, accumulation of adriamycin (ADM) was decreased, and the sensitivity to vincristine (VCR), ADM and 5-fluorouracil (5-FU) was increased compared with the parent KBv200 cells. After treatment with ADM and VCR, the p53-transfectants were more susceptible to apoptosis. The results suggest that the increase in drug sensitivity of the cells may be, at least in part, due to p53-dependent apoptosis induced by anticancer agents.
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994
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Li ZH, Feng XB, Xi ZT. [Effect of chaihu guizhi decoction on the immunoglobulin and IgG subgroup in children with recurrent respiratory tract infection]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1997; 17:653-4. [PMID: 10322843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
OBJECTIVE To observe the effect of Chaihu Guizhi Decoction (CGD) on Immunoglobulin (Ig) and IgG subgroup in children with recurrent respiratory tract infection (RRTI). METHODS Levels of Ig and IgG subgroup were measured in 23 cases of children with RRTI before and after treating with CGD, and compared with those in the control group. RESULTS In RRTI group, the levels of IgG, IgA, IgM and IgG1 were lower than those of the control groups respectively (P < 0.01). The rate of IgG subgroup deficiency (ISD) was 60.9%. The effective rate of the CGD group was 95.6%. The IgG and IgG1 levels were increased after treatment as compared with before treatment (P < 0.05), and the ISD correcting rate being 71.4%. CONCLUSIONS The hypoimmunofunction and IgG subgroup deficiency were important factors in RRTI pathogenesis. The CGD could improve the immunofunction and correct the IgG subgroup deficiency, and this effect might be one of the mechanism of CGD in treating RRTI.
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995
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Ge Y, Li ZH, Yung YP, Ratzkin BJ, Broxmeyer HE, Lu L. Up-regulation of Tie gene expression by leukemia inhibitory factor and steel factor in CD34+ cells from human umbilical cord blood. J Leukoc Biol 1997; 62:510-6. [PMID: 9335322 DOI: 10.1002/jlb.62.4.510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Tie, a new receptor tyrosine kinase, is expressed in vascular endothelial and hematopoietic cells. To determine whether Tie might be involved in early hematopoiesis, we asked whether the Tie gene is expressed in normal human hematopoietic stem/progenitor cells and if the expression of this gene could be regulated. Using a single-cell reverse-transcriptase polymerase chain reaction (RT-PCR) assay to study expression of the Tie gene in the subset of human umbilical cord blood (UCB) CD34+++ primitive stem/ progenitor cells with extensive replating capacity, we demonstrated at the single isolated cell level that Tie was expressed in these cells. The expression of Tie gene in CD34+ cells was at a low level but was enhanced up to two- to fourfold by steel factor (SLF) or leukemia inhibitory factor (LIF), two cytokines that regulate production of stem/progenitor cells, as assessed using competitive PCR and semi-quantitative RT-PCR assays. The fold increases were observed as early as 2 h for SLF and 4 h for LIF and remained elevated for 24 h. These results demonstrate modulation of gene regulation in the rare populations of CD34+ cells and suggest the possibility that Tie may play a role in the proliferation and differentiation of immature hematopoietic cells.
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996
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Li ZH, Zhu YJ, Chao LS, Li XT. [Wild-type p53 stimulates vincristine-induced apoptosis]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1997; 32:565-8. [PMID: 11596302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Recent studies indicate that wild-type p53 can trigger cell apoptosis induced by many chemotherapeutic agents which induce DNA damage or cause disruptions of DNA metabolism, such as ADM, 5-FU, VP-16 and radiation. We introduced the wild-type p53 gene into a MDR cell line KBV200 in which the endogenous p53 was found to be rearranged. By G418 selection and Northern blot analysis, a G418-resistant clone named KBV200-p53 was obtained which continuously expressed the exogenous wild-type p53 mRNA. After treatment with Vincristine(VCR), the wild type p53-expression cells presented typical morphology characteristic of apoptosis analysed under electron and fluorescence microscopes. Flow cytometer analysis showed that the KBV200-p53 cells were more readily undergo apoptosis than their parental cells KBV200. After treatment with VCR 600 nmol.L-1 for 24 h, the apoptotic percentage of KBV200-p53 and KBV200 cells was about 42.4% and 8.4%, respectively. This result indicates that wild-type p53 stimulates VCR-induced apoptosis in KBV200 cells.
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997
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Zhou T, Chen BN, Li ZH. [Clinical study on treatment of arteriosclerosis obliterans using huangqi tongmai decoction]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1997; 17:408-9. [PMID: 10322860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
OBJECTIVE To test and verify the effects of Huangqi Tongmai Decoction (HQTMI) regulating blood lipid in treating arteriosclerosis obliterans (ASO). METHODS Thirty-two cases of ASO was treated with HQTMD for two months. The drug was in water decoction, oral taken. RESULTS Compared with the blood lipid level before treatment, the high density lipoprotein of cholesterol (HDL-C) was increased, the low density lipoprotein of cholesterol (LDL-C), atherogenic index (AI) was decreased (P < 0.01). The serum total cholesterol (TC), triglyceride (TG), very low density lipoprotein of cholesterol (VLDL), apolipoprotein A1 (apoA1), apolipoprotein B100 (apoB100) were all changed (P < 0.05). apoA1/apoB100 ratio increased. CONCLUSION HQTMD could regulate blood lipid. This method was effective in treating ASO.
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998
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Zhou Y, Li ZH, Chen M. [Endoscopic papillosphincterotomy for the treatment of pancreaticobiliary disease]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1997; 35:274-6. [PMID: 10374559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
From July 1987 to March 1996, endoscopic papillosphincterotomy (EST) was performed in 346 patients of 2,700 cases undergoing ERCP. Maj or indications for EST were choledocholithiasis, constrictive papillitis, chronic pancreatitis, biliary ascariasis and dysfunction of Oddi's sphincter. The EST was successful in 331 cases, ang the overall success rate was 95.7%. The stone discharge rate was 96%. The stricturotomy rate was 93.8%. The failure rate was 4.3% (15 cases). Clinical application and prevention of complications for EST were discussed.
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999
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Cundy KC, Li ZH, Hitchcock MJ, Lee WA. Pharmacokinetics of cidofovir in monkeys. Evidence for a prolonged elimination phase representing phosphorylated drug. Drug Metab Dispos 1996; 24:738-44. [PMID: 8818570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
After intravenous administration of [14C]cidofovir to African green monkeys (43 mg/kg, 29.5 microCi/kg), the drug distributed rapidly into extracellular fluid. Concentrations of radioactivity in plasma were described by a three-compartment model with alpha, beta, and gamma half-lives of 0.67, 3.02, and 36.0 hr, respectively (N = 3). These phases are believed to represent renal elimination, efflux of free cidofovir from cells, and efflux from cells of cidofovir produced from dephosphorylation of metabolites, respectively. Less than 5% of the dose was phosphorylated, based on the proportion of total AUC in the gamma-phase. The clearance of cidofovir (211 +/- 16.6 ml/hr/kg) was dependent on dose and exceeded the theoretical glomerular filtration rate. Concentrations of cidofovir in kidney declined with a half-life of 23 hr and were > 1,000-fold higher than plasma levels by 120 hr. Clearance of cidofovir after multiple intravenous doses of 4.9 mg/kg/day (18.5 microCi/kg/day) decreased significantly by day 10, consistent with the observed nephrotoxicity. Oral and subcutaneous bioavailabilities of cidofovir were 21.8 +/- 9.44 and 98.5 +/- 15.8%, respectively. After intravenous administration of [14C]cidofovir to cynomolgus monkeys (10 mg/kg, 100 microCi/kg) alone or 1 hr after oral probenecid (30 mg/kg), mean +/- SD (N = 3) urinary recoveries of total radioactive dose were 91.4 +/- 11.3% and 94.4 +/- 29.8%, respectively, at 7 days postdose. The mean +/- SD half-lives of the terminal elimination phases were 33.3 +/- 10.6 and 24.4 +/- 5.0 hr, respectively. Cidofovir accounted for 98% of the radioactivity recovered in urine; the remainder was attributed to cidofovir phosphocholine. The prolonged elimination phase observed in monkeys is consistent with the long intracellular half-life of phosphorylated cidofovir in vitro and supports infrequent dosing of the drug for antiviral therapy.
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Broxmeyer HE, Cooper S, Li ZH, Lu L, Sarris A, Wang MH, Chang MS, Donner DB, Leonard EJ. Macrophage-stimulating protein, a ligand for the RON receptor protein tyrosine kinase, suppresses myeloid progenitor cell proliferation and synergizes with vascular endothelial cell growth factor and members of the chemokine family. Ann Hematol 1996; 73:1-9. [PMID: 8695717 DOI: 10.1007/s002770050192] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Macrophage-stimulating protein (MSP), originally identified as an inducer of murine resident macrophage responsiveness to chemoattractants, is a ligand for human RON/murine STK receptor protein tyrosine kinases. Since STK was cloned from populations enriched for hematopoietic stem cells, we initiated studies on the effects of MSP on colony formation by granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and multipotential (CFU-GEMM) myeloid progenitor cells. MSP alone had no colony stimulating activity. However, MSP caused about a 50% suppression of CFU-GM colony formation induced by synergistic combinations of SLF or Flt-L plus GM-CSF, G-CSF, or IL-3 and of BFU-E and CFU-GEMM colonies induced by SLF or Flt3-L plus Epo or Epo and IL-3. In contrast, MSP had no effect on progenitors stimulated by one growth factor. MSP also suppressed colony formation by stimulated cord blood progenitors, but only after preinduction to a rapidly cycling state. It was previously reported that several members of the chemokine family synergistically suppress myeloid progenitor proliferation. Likewise, synergistic suppression was observed when MSP was paired with VEGF, MIP-1 alpha, IL-8, PF4, MCP-1, IP-10, or ENA-78, or when VEGF was paired with the chemokines; and the required MSP concentration was more than 100-fold less than for MSP alone. Additionally, MSP or VEGF inhibited proliferation of the human myeloid growth factor-dependent cell line, M07e, but a sustained effect required multiple additions over time. At the least, some of the MSP suppressive effects on myeloid progenitors, as assessed on single isolated CD34 marrow cells, appeared to be directly on the progenitors; sustained additions of MSP were required to see this effect. The suppressive action of MSP and its synergism with proteins of the chemokine family may be of relevance to regulation of blood cell production.
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