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Kramer RE, Sokol RJ, Yerushalmi B, Liu E, MacKenzie T, Hoffenberg EJ, Narkewicz MR. Large-volume paracentesis in the management of ascites in children. J Pediatr Gastroenterol Nutr 2001; 33:245-9. [PMID: 11593116 DOI: 10.1097/00005176-200109000-00003] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Large-volume paracentesis has been evaluated for both therapeutic and diagnostic purposes in the management of ascites in cirrhotic adults. There are no published data relating to the safety, efficacy, or methods of this procedure in children. The objective of this study was to characterize the authors' initial experience with large-volume paracentesis (> 50 ml/kg of ascites) for removal of tense abdominal ascites in the pediatric population. METHODS Retrospective chart review was performed of 21 large-volume paracentesis sessions in seven children (ages 6 months-18 years) with tense ascites that did not respond to other measures. RESULTS Mean volume removed was 3,129 +/- 2,966 ml (mean +/- standard deviation) or 118 +/- 56 ml/kg over 2.9 +/- 3.7 hours by a 16-gauge intravascular catheter in 6 sessions, by an 18-gauge intravascular catheter in three sessions, and by a 15-gauge fenestrated, stainless-steel paracentesis needle in 12 sessions. Large-volume paracenteses performed with the paracentesis needle had significantly shorter duration of drainage and faster flow rates than those performed with the intravascular catheter. The only complication encountered was decreased urine output in one session. CONCLUSIONS Large-volume paracentesis is a safe and effective therapeutic method for managing tense abdominal ascites in children. The use of the paracentesis needle significantly improved the speed and efficiency of large-volume paracentesis compared with the intravascular catheter.
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Liu E, Tu W, Law HK, Lau YL. Changes of CD14 and CD1a expression in response to IL-4 and granulocyte-macrophage colony-stimulating factor are different in cord blood and adult blood monocytes. Pediatr Res 2001; 50:184-9. [PMID: 11477201 DOI: 10.1203/00006450-200108000-00004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Neonates are relatively immature in their immune response; thus, to further clarify the differences of monocyte function and differentiation between neonates and adults, we investigated their CD14(+)CD4(+) and CD14(+)CD16(+) monocyte subpopulations, production of IL-1beta and tumor necrosis factor-alpha induced by lipopolysaccharide, and their CD14 and CD1a phenotypic changes in response to IL-4 and granulocyte-macrophage colony-stimulating factor. Our results showed that 1) the expression of CD14 in cord blood monocytes was significantly lower than that in adult peripheral blood monocytes; 2) both the percentages of CD14(+)CD4(+) cells and CD14(+)CD16(+) cells among CD14(+) monocytes were also significantly lower in cord blood; 3) after stimulation by lipopolysaccharide for 72 h, production of both IL-1beta and tumor necrosis factor-alpha was lower in cord blood than that in adult peripheral blood; and 4) in response to IL-4 or GM-CSF, the phenotype development of CD14 and CD1a in cord blood and adult peripheral blood was different. Down-regulation of CD14 expression in response to IL-4 and GM-CSF was slower in cord blood monocytes than that in adult peripheral blood monocytes. After 9 d of culture in the presence of IL-4 and GM-CSF, the percentage of CD1a(+) monocytes was significantly more increased in cord blood than that in adult peripheral blood. The reduced expression of CD14 and other mature phenotype markers such as CD16 and CD4 as well as the reduced IL-1beta and tumor necrosis factor-alpha production may contribute to the impaired immune response of neonates. Slower down-regulation of CD14 by IL-4 and GM-CSF suggests that differential properties of cord blood monocytes in response to cellular stress signals take a longer time than those of adult peripheral blood monocytes.
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253
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Abiru N, Yu L, Miao D, Maniatis AK, Liu E, Moriyama H, Eisenbarth GS. Transient insulin autoantibody expression independent of development of diabetes: comparison of NOD and NOR strains. J Autoimmun 2001; 17:1-6. [PMID: 11488632 DOI: 10.1006/jaut.2001.0530] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NOD mice spontaneously develop anti-insulin autoantibodies associated with the subsequent development of diabetes. NOD mice that express insulin autoantibodies at 8 weeks of age have a diabetes risk exceeding 90%, while mice that do not express autoantibodies by 16 weeks have a risk of less than 20%. NOD female mice expressed insulin autoantibodies more often than male mice (13/15+ vs. 6/15+). Autoantibodies characteristically developed between 8 and 20 weeks and then for most mice became negative at diabetes onset in NOD mice. In the diabetes-free strain NOR mice, spontaneous expression of insulin autoantibodies was observed in less mice (female 8/15+, male 3/10+) compared to NOD mice. The expression of autoantibodies was transient in NOR mice and followed the same time-course as for NOD mice and they were all negative by 28 weeks (without progression to diabetes). No correlation was found in NOR mice between the levels of autoantibodies and insulitis. The program of insulin autoantibody expression is regulated over approximately 5 months for both NOD and NOR mice with only NOD mice developing diabetes, indicating that depending upon genetic combination, the presence of insulin autoantibodies does not always predict diabetes development. In addition, this data is not consistent with the hypothesis that the time-course of autoantibodies simply reflects the destruction of beta-cells with development of diabetes.
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Liu E. Edison Liu--Director of the Genome Institute of Singapore (interview by Ezzie Hutchinson). Lancet Oncol 2001; 2:385-8. [PMID: 11905756 DOI: 10.1016/s1470-2045(00)00394-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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255
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Liu E, Tu W, Law HK, Lau YL. Decreased yield, phenotypic expression and function of immature monocyte-derived dendritic cells in cord blood. Br J Haematol 2001; 113:240-6. [PMID: 11328307 DOI: 10.1046/j.1365-2141.2001.02720.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Dendritic cells are critical for the induction of both primary immune responses and immunological tolerance, as well as for the regulation of T-helper 1 (Th1) and 2 (Th2) immune responses. As neonates are notably deficient in Th1 response and cord blood transplantation is noted to result in less graft-versus-host disease (GvHD), we compared the phenotypic and functional characteristics of monocyte-derived dendritic cells (DCs) that favour Th1 development from cord blood and adult peripheral blood to understand the underlying mechanisms of these observations. Our results showed that: (1) after culture for 7 d with interleukin (IL)-4 and granulocyte--macrophage colony-stimulating factor (GM-CSF), cord blood monocytes generated less CD1a(+) cells than adult peripheral blood monocytes, and the CD1a+ cell percentage decreased thereafter; (2) compared with adult blood DCs, cord blood DCs had reduced intensity of expression of CD1a and MHC class II molecules, but the expression levels of CD11c and CD86 were similar; (3) the endocytotic ability of cord blood DCs was reduced compared with adult blood DCs, and this function was related to reduced mannose receptor (MR)-positive cells; (4) furthermore, the ability of cord blood DCs to stimulate CD3(+) T cells in an allogeneic mixed lymphocyte reaction was significantly lower than that of adult blood DCs. These results suggested that the dysfunction of cord blood monocytes in differentiating into professional DCs will affect the activation of naive T cells, especially Th1 development, and may be related to the susceptibility to different infections in the neonates, as well as the lower incidence of GvHD in cord blood transplantation.
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Inagaki-Ohara K, Yada S, Takamura N, Reaves M, Yu X, Liu E, Rooney I, Nicholas S, Castro A, Ware CF, Green DR, Lin T. p53-dependent radiation-induced crypt intestinal epithelial cells apoptosis is mediated in part through TNF-TNFR1 system. Oncogene 2001; 20:812-8. [PMID: 11314015 DOI: 10.1038/sj.onc.1204172] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2000] [Revised: 12/08/2000] [Accepted: 12/12/2000] [Indexed: 11/09/2022]
Abstract
Radiation induces apoptosis of crypt intestinal epithelial cells (IEC) through a pathway that is largely dependent on p53. However, exactly how p53 mediates IEC apoptosis is unclear. Studies in vitro suggest that one mechanism by which p53 mediates apoptosis is through its ability to transactivate members of the TNF receptor family of 'Death Receptors'. Here, we examined the role of one of its member, TNF receptor type 1 (TNFR1), in an in vivo model of p53-dependent radiation-induced IEC apoptosis. We demonstrate that mice genetically engineered to be deficient in TNF receptor type 1 (TNFR1(-/-)) and mice injected with TNFR1-fusion chimeric protein (TNFR1-Fc; a competitive inhibitor of TNFR1) were partially protected (30-40%) from p53-dependent radiation-induced IEC apoptosis. However, we found no evidence to support the possibility p53 transcriptionally regulates the expression of TNFR1 nor increases the susceptibility of IEC to TNF-mediated apoptosis. Interestingly, we found that injection of TNF readily induced IEC apoptosis and that radiation induced a p53-dependent increase in the intestinal level of TNF. Furthermore, injection of a neutralizing anti-TNF mAb reduced p53-dependent radiation-induced IEC apoptosis by approximately 60%. Overall, these results suggest that p53-dependent radiation-induced IEC apoptosis is mediated in part through ability of p53 to regulate TNF, which subsequently induces IEC apoptosis through TNFR1.
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Peng Y, Xue J, Huang J, Lin Z, Liu E, Chen N, Huang J. [Study on the aggregation state of sulfonated phthalimidomethyl zinc phthalocyanine in CEL solution]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2000; 20:875-877. [PMID: 12938501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Sulfonated Phthalimidomethyl Zinc Phthalocyanine is a new photodynamic therapy reagent, it can be selectively attacked to cell, but how it attacks the target cell is still unknowable. The aggregation state of photosensitizer is significant to its mechanism proved in CEL solution. The aggregation of ZnPcS2P2 in CEL has been studied with absorption spectroscopy and fluorescence spectroscopy. The aggregation state is dimer through theory analysis, monomer molar absorption coefficient as well as equilibrium constant were estimated.
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Huang J, Liu E, Dai Z, Shen C, Yang S, Chen N, Huang J. [The molecular spectra and existence state of sulfonated phthalimidomethyl phthalocyanine hydroxyl aluminum as amphiphilic photosensitizer in aqueous alcoholic solutions and water]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2000; 20:673-676. [PMID: 12945414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The sulfonated phthalimidomethyl phthalocyanine hydroxyl aluminum (Al(OH)PcSP) is an amphiphilic photosensitizer which was proved to have the photodynamic activities against cancer. The electronic absorption spectra and aggregation state of the Al(OH)PcSP in aqueous alcoholic solutions and water were investigated. The results showed that the Al(OH)PcSP existed in the form of monomer in aqueous alcoholic solutions. The increase in the carbon chain and hydroxy of alcohol in solutions had no significant effects on the absorption spectra behaviors of Al(OH)PcSP. But in water, the Al(OH)PcSP existed in the equilibrium between monomer and dimer. The dimerization constant was 5.7307 x 10(4) mol-1.L. The characteristic absorption peak of the Q band of the Al(OH)PcSP dimer was red shifted to 740.5 nm from that of the monomer (676.5 nm), which contrast with those of other metal phthalocyanines dimer. The study on the fluorescence spectra of Al(OH)PcSP in aqueous alcoholic solutions suggested that the fluorescence of the dimer was weak.
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259
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Liu E, Thant AA, Kikkawa F, Kurata H, Tanaka S, Nawa A, Mizutani S, Matsuda S, Hanafusa H, Hamaguchi M. The Ras-mitogen-activated protein kinase pathway is critical for the activation of matrix metalloproteinase secretion and the invasiveness in v-crk-transformed 3Y1. Cancer Res 2000; 60:2361-4. [PMID: 10811109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
To search for the intracellular signaling pathway critical for the secretion of matrix metalloproteinases (MMP), we studied the effects of dominant negative Ras (S17N Ras) and dominant negative MEK1 (MEK1AA) expression in v-crk-transformed 3Y1. Expression of either S17N Ras or MEK1AA dramatically suppressed the augmented secretion of MMP-2 and MMP-9 in v-crk-transfected 3Y1. Similarly, a Ras farnesyltransferase inhibitor, manumycin A, and a MEK1 inhibitor, U0126, suppressed MMP secretion in a dose-dependent manner, whereas a PI3 kinase inhibitor, wortmannin, could not. In addition, the suppression of MMP secretion by S17N Ras showed good correlation with the inhibition of in vitro invasiveness of the cells. In contrast, expression of dominant negative C3G did not suppress MMP secretion, although it substantially blocked the c-Jun N-terminal kinase activation. Taken together, the Ras-MEK1 pathway, but not the C3G-JNK pathway, seems to play a key role in the activation of MMP secretion and, hence, the invasiveness of v-crk-transformed cells.
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Epstein JA, Li J, Lang D, Chen F, Brown CB, Jin F, Lu MM, Thomas M, Liu E, Wessels A, Lo CW. Migration of cardiac neural crest cells in Splotch embryos. Development 2000; 127:1869-78. [PMID: 10751175 DOI: 10.1242/dev.127.9.1869] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pax3 encodes a transcription factor expressed during mid-gestation in the region of the dorsal neural tube that gives rise to migrating neural crest populations. In the absence of Pax3, both humans and mice develop with neural crest defects. Homozygous Splotch embryos that lack Pax3 die by embryonic day 13.5 with cardiac defects that resemble those induced by neural crest ablation in chick models. This has led to the hypothesis that Pax3 is required for cardiac neural crest migration. However, cardiac derivatives of Pax3-expressing precursor cells have not been previously defined, and Pax3-expressing cells within the heart have not been well demonstrated. Hence, the precise role of Pax3 during cardiac development remains unclear. Here, we use a Cre-lox method to fate map Pax3-expressing neural crest precursors to the cardiac outflow tract. We show that although Pax3 itself is extinguished prior to neural crest populating the heart, derivatives of these precursors contribute to the aorticopulmonary septum. We further show that neural crest cells are found in the outflow tract of Splotch embryos, albeit in reduced numbers. This indicates that contrary to prior reports, Pax3 is not required for cardiac neural crest migration. Using a neural tube explant culture assay, we demonstrate that neural crest cells from Splotch embryos show normal rates of proliferation but altered migratory characteristics. These studies suggest that Pax3 is required for fine tuning the migratory behavior of the cardiac neural crest cells while it is not essential for neural crest migration.
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An Y, Liu E, Liu X, Yang F, Han F, Dai Q. Protective effect of melatonin on neural cells against the cytotoxicity of oxyradicals. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 2000; 15:40-4. [PMID: 12899398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To investigate the exact mechanism of melatonin to prohibit the apoptosis of neural cells induced by various kinds of cytotoxic agents. METHODS We used the methods of phase contrast microscopy, MTT assay and hoechst dye staining to check this mechanism in SKNSH and U251 cell lines. RESULTS Both 2 mmol/L H2O2 and 0.5 micromol/L amyloid beta-protein (Abeta) induce these two cell lines die via apoptosis. Either melatonin or glutathione can significantly protect both cell lines. The protective effect of 10 micromol/L melatonin is as same as that of 60 micromol/L glutathione. CONCLUSION Melatonin can partly inhibit the cytotoxicity of H2O2 and Abeta through its role as a free radical scavenger.
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Huang J, Liu E, Yang S, Chen N, Huang J, Duan J, Chen Y. [The monomer electronic spectra and fluorescence spectra of some metal phthalocyanines]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2000; 20:95-98. [PMID: 12953463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The monomer electronic absorption spectra of the ZnPcS2P2 (disulfonated diphthalimidomethyl phthalocyanine zinc) in 11 kinds of solvents and 5 kinds of unsubstituted metal phthalocyanines in DMF were investigated. The monomer electronic absorption spectra of some substituted phthalocyanine zinc including ZnPcS4 (tetrasulfonated phthalocyanine zinc), ZnPcS4 (tetraphthalimidomethyl phthalocyanine zinc), ZnPc(NO2)4 (tetranitro phthalocyanine zinc) and ZnPcS2P2 in the same solvent were also studied. The result showed that (1) with the strengthening of coordination ability of the solvent, the maximum absorption wavelength of ZnPcS2P2 increased slightly. (2) with the increasing of electronegativity of central ion, the maximum absorption wavelength of MPcs had a little blue shift. (3) the electron-donating substituting group caused slightly blue shift. The monomer fluorescence spectra of ZnPcS4, ZnPcP4, and ZnPcS2P2 in different solvents were determined. The result showed that (1) the electron-withdrawing substituting group caused slightly red shift of the fluorescence spectra. (2) with the strenghtening of coordination ability of the solvent, the maximum emission wavelength increased slightly. (3) the fluorescence intensity of ZnPcS2P2 in the solution which contains Cremophor EL was remarkable stronger than that in other solvents. This is an important suggest to the development of photodynamic diagnose agent. The effect of solvents, central ions and substituents on spectra were partly explained by means of the quantrum chemistry.
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263
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Després C, DeLong C, Glaze S, Liu E, Fobert PR. The Arabidopsis NPR1/NIM1 protein enhances the DNA binding activity of a subgroup of the TGA family of bZIP transcription factors. THE PLANT CELL 2000. [PMID: 10662863 DOI: 10.1105/tpc.12.2.279] [Citation(s) in RCA: 322] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The Arabidopsis NPR1 gene is essential in activating systemic, inducible plant defense responses. To gain a better understanding of NPR1 function, we conducted a yeast two-hybrid screening procedure and identified a differential interaction between NPR1 and all known members of the Arabidopsis TGA family of basic leucine zipper transcription factors. In the electrophoretic mobility shift assay, NPR1 substantially increased the binding of TGA2 to its cognate promoter element (as-1) as well as to a positive salicylic acid-inducible element (LS7) and a negative element (LS5) in the promoter of the pathogenesis-related PR-1 gene. Proteins encoded by npr1 mutants interacted poorly with TGA2 and did not substantially increase TGA2 binding to the as-1, LS5, or LS7 elements, thus establishing a link between the loss of disease resistance and the loss of TGA2 interaction and NPR1-enhanced DNA binding. Coupled with observations that the DNA binding activity of TGA factors is deregulated in npr1 plants, the results suggest that NPR1-mediated DNA binding of TGA2 is critical for activation of defense genes.
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Després C, DeLong C, Glaze S, Liu E, Fobert PR. The Arabidopsis NPR1/NIM1 protein enhances the DNA binding activity of a subgroup of the TGA family of bZIP transcription factors. THE PLANT CELL 2000; 12:279-90. [PMID: 10662863 PMCID: PMC139764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/22/1999] [Accepted: 12/15/1999] [Indexed: 05/15/2024]
Abstract
The Arabidopsis NPR1 gene is essential in activating systemic, inducible plant defense responses. To gain a better understanding of NPR1 function, we conducted a yeast two-hybrid screening procedure and identified a differential interaction between NPR1 and all known members of the Arabidopsis TGA family of basic leucine zipper transcription factors. In the electrophoretic mobility shift assay, NPR1 substantially increased the binding of TGA2 to its cognate promoter element (as-1) as well as to a positive salicylic acid-inducible element (LS7) and a negative element (LS5) in the promoter of the pathogenesis-related PR-1 gene. Proteins encoded by npr1 mutants interacted poorly with TGA2 and did not substantially increase TGA2 binding to the as-1, LS5, or LS7 elements, thus establishing a link between the loss of disease resistance and the loss of TGA2 interaction and NPR1-enhanced DNA binding. Coupled with observations that the DNA binding activity of TGA factors is deregulated in npr1 plants, the results suggest that NPR1-mediated DNA binding of TGA2 is critical for activation of defense genes.
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Liu E, Pan X, Liu R, Tan Y, Jin Z, Wei G, Liu Y, Hu N. [Hyperconjugation, characteristic infrared absorption of methylsulfones and crystal structures of selected aromaticsulfones]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2000; 20:31-39. [PMID: 12953445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A branched absorption peak with medium intensity at (970 +/- 20) cm-1 appears only in the infrared spectra of methylsulfones. The below mentioned aromaticsulfones are chosen to reveal the specificity. Crystal and molecular parameters of CH3CONH-C6H4-SO2R(R = -CH3, -CH2CH2OH)-CH2CONH2, are determined by application of single crystal diffraction of X-ray through Nicolet R3M/E diffracometer. The existence of hyperconjugation and its natures in group -SO2CH3, confirmed by further analyses on the parameters, result in the specificity of IR absorption of the group, which is proved characteristic and can be used to identify methylsulfones. The first part describes the detection results, ascertains their crystal and molecular structures, and shows that the aromaticsulfone exists as cross linking multi-molecules when R = -CH2CONH2 or as double molecules when R = -CH2CH2OH because of H bonds. The second part covers analyses on their molecular structures. The analyses demonstrate the hyperconjugation between sigma S-C and pi S-C in group -SO2CH3. The sigma C-H hyperconjugate with pi S-O. The strength of hyperconjugated bond C-H decreases and its length tends longer. Due to the effect, the bond S-C is not a pure single bond sigma, but one which possesses a certain degree of a double bond. Its IR wave number, between those of sigma S-C and pi S-C, attributes to the medium branched peak at (970 +/- 20) cm-1. The peak branch reflects two groups of the most stable hyperconjugating conformational isomers. The hyperconjugation is weakened by the substitution of one non H group for one H atom in -SO2CH3 and if the non H group does not conjugate with pi S-O, the absorption at (970 +/- 20) cm-1 disappears as a characteristic peak. The intensity of absorption at (970 +/- 20) cm-1 conforms to the intensity of hyperconjugation between pi S-O and its adjacent sigma C-H. The third part introduces syntheses of the products, crystal preparations and their detections through X-ray diffraction.
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Hidi R, Timmermans S, Liu E, Schudt C, Dent G, Holgate ST, Djukanović R. Phosphodiesterase and cyclic adenosine monophosphate-dependent inhibition of T-lymphocyte chemotaxis. Eur Respir J 2000; 15:342-9. [PMID: 10706503 DOI: 10.1034/j.1399-3003.2000.15b21.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
There is abundant evidence for T-lymphocyte recruitment into the airways in allergic inflammatory responses. This study has tested the hypothesis that T-cell chemotaxis induced by platelet-activating factor (PAF) and human recombinant interleukin-8 (hrIL-8) can be attenuated by inhibition of phosphodiesterase activity and raised intracellular 3',5'-cyclic adenosine monophosphate (cAMP) levels. This study used theophylline, a nonselective phosphodiesterase (PDE) inhibitor, and rolipram, a selective PDE4 inhibitor, to study the effect of PDE inhibition on T-cell chemotaxis. The beta2-adrenoceptor agonist, salbutamol, the adenylyl cyclase activator, forskolin, and the cAMP analogue, dibutyryl cAMP (db-cAMP), were used to demonstrate a role for raised cAMP levels. T-cells were obtained from 10 atopic asthmatics, and the phenotype of migrating cells was examined by flow cytometry. Theophylline caused an inhibition of both PAF-and hrIL-8-induced chemotaxis (mean+/-SEM maximum inhibition at 1 mM: 73+/-4% and 48+/-8% for hrIL-8 and PAF, respectively) that was not specific for the CD4+, CD8+, CD45RO+ or CD45RA+ T-cell subsets. T-cell chemotaxis was more sensitive to treatment with rolipram whose effect was already significant from 0.1 microM on hrIL-8-induced chemotaxis. Both a low concentration of salbutamol (0.1 mM) and forskolin (10 microM) potentiated the inhibitory effect of a low concentration of theophylline (25 microM) on responses to PAF but not to hrIL-8. Finally, T-cell chemotaxis was also inhibited by db-cAMP. It is concluded that attenuation of T-cell chemotaxis to two chemoattractants of relevance to asthma pathogenesis can be achieved via phosphodiesterase inhibition and increased intracellular 3', 5'-cyclic monophosphate using drugs active on cyclic nucleotide phosphodiesterase. This action may explain the anti-inflammatory effects of theophylline and related drugs in asthma.
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Peters A, Liu E, Verrier RL, Schwartz J, Gold DR, Mittleman M, Baliff J, Oh JA, Allen G, Monahan K, Dockery DW. Air pollution and incidence of cardiac arrhythmia. Epidemiology 2000; 11:11-7. [PMID: 10615837 DOI: 10.1097/00001648-200001000-00005] [Citation(s) in RCA: 456] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Air pollution episodes have been associated with increased cardiovascular hospital admissions and mortality in time-series studies. We tested the hypothesis that patients with implanted cardioverter defibrillators experience potentially life-threatening arrhythmias after such air pollution episodes. We compared defibrillator discharge interventions among 100 patients with such devices in eastern Massachusetts, according to variations in concentrations of particulate matter, black carbon, and gaseous air pollutants that were measured daily for the years 1995 through 1997. A 26-ppb increase in nitrogen dioxide was associated with increased defibrillator interventions 2 days later (odds ratio = 1.8; 95% confidence interval = 1.1-2.9). Patients with ten or more interventions experienced increased arrhythmias in association with nitrogen dioxide, carbon monoxide, black carbon, and fine particle mass. These results suggest that elevated levels air pollutants are associated with potentially life-threatening arrhythmia leading to therapeutic interventions by an implanted cardioverter defibrillator.
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Liu E. Bragdon v. Abbott: extending the Americans with Disability Act to asymptomatic individuals. JOURNAL OF HEALTH CARE LAW & POLICY 2000; 3:382-408. [PMID: 15015486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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269
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Thant AA, Sein TT, Liu E, Machida K, Kikkawa F, Koike T, Seiki M, Matsuda S, Hamaguchi M. Ras pathway is required for the activation of MMP-2 secretion and for the invasion of src-transformed 3Y1. Oncogene 1999; 18:6555-63. [PMID: 10597259 DOI: 10.1038/sj.onc.1203049] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To search for the signaling pathway critical for tumor invasion, we examined the effects of dominant negative ras (S17N ras) expression on the activation of matrix metalloproteinase-2 (MMP-2) in src-transformed 3Y1, SR3Y1, under the control of conditionally inducible promoter. In SR3Y1 clones transfected with S17N ras, augmented secretion and proteolytic activation of MMP-2 were dramatically suppressed by S17N Ras expression, while tyrosine phosphorylation of cellular proteins was not suppressed. We found that invasiveness of SR3Y1 cells assayed by the modified Boyden Chamber method was strongly suppressed by S17N Ras expression. In contrast, cell morphology reverted partially and glucose uptake remained unchanged by S17N Ras expression. In addition, treatment of SR3Y1 with manumycin A, a potent inhibitor of Ras farnesyltransferase, strongly suppressed both augmented secretion and proteolytic activation of MMP-2. Contrary, treatment of SR3Y1 with wortmannin or TPA showed no clear effect on MMP-2 activation. Thus, these results strongly suggest that Ras-signaling, but neither P13 kinase- nor protein kinase C-signalings, plays a critical role in activation of MMP-2 and, subsequently, in the invasiveness of src-transformed cells.
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Liu E, Nijhawan N, Gladman D, Lam WC, Buys Y. Primary antiphospholipid syndrome and neovascular glaucoma. CANADIAN JOURNAL OF OPHTHALMOLOGY 1999; 34:349-52. [PMID: 10604059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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271
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Liu Y, Sun F, Yuan Z, Liu E, Zhang Y. [Location of the binary toxin gene of Bacillus sphaeriucs and some biological characteristics of its asprogenous mutants]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1999; 39:426-9. [PMID: 12555523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Location of the binary toxin gene of Bs C3-41 and some biological characteristics of its asporogenous mutants which obtained by DES treatment were studied in this paper. Mutant C4, L5 with blocked at the stage II of sporulation course were not possessed of any crystalline inclusion, but the binary toxin proteins were detected in their cells by SDS-PAGE analysis. Another mutant G5 which blocked at the stage III of sporulation course formed parasporal crystal in the cells, and its toxicity to larvae of Culex quinquefasciatus was about 50 times higher than those of mutant C4 and L5. The result of curing plasmid and Southern blot analysis confirm the binary toxin gene of Bs C3-41, Bs 1691 and Bs-10 locate on the chromosome.
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272
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Pai-Scherf LH, Villa J, Pearson D, Watson T, Liu E, Willingham MC, Pastan I. Hepatotoxicity in cancer patients receiving erb-38, a recombinant immunotoxin that targets the erbB2 receptor. Clin Cancer Res 1999; 5:2311-5. [PMID: 10499598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
To exploit overexpression of erbB2 in human cancers, we constructed a single-chain immunotoxin (erb-38) that contains the Fv portion of monoclonal antibody e23 fused to a truncated form of Pseudomonas exotoxin A. In a Phase I study, five breast cancer patients and one esophageal cancer patient received three doses of erb-38 at 1.0 and 2.0 microg/kg. Hepatotoxicity was observed in all patients. Immunohistochemistry showed the presence of erbB2 on hepatocytes explaining the liver toxicity of erb-38. We suggest that targeting of tumors with antibodies to erbB2 armed with radioisotopes or other toxic agents may result in unexpected organ toxicities due to erbB2 on normal cells.
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273
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Tay BK, Shi X, Liu E, Tan HS, Cheah LK, Shi J, Lim EC, Lee HY. Tribological and optical properties of hydrogen-free amorphous carbon films with varying sp3/sp2 composition. SURF INTERFACE ANAL 1999. [DOI: 10.1002/(sici)1096-9918(199908)28:1<226::aid-sia582>3.0.co;2-t] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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274
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Su Q, Liu E, Chen C, Feng Y, Wang W, Wang Z. [The expression of MTS1 gene product in transitional mucosa adjacent to rectal carcinomas and its clinical significance]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1999; 37:494-6. [PMID: 11829899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To study the property of transitional mucosa (TM) adjacent to rectal carcinoma and the clinical significance of MTS1 gene deficit. METHODS We used the immunohistochemical methods to observe the range of TM adjacent to rectal carcinoma, and the immunohistochemical method to observe the expression of MTS1 gene product on TM, using normal mucosa and carcinoma tissue as control. RESULTS The positive expression level of MTS1 gene product was the highest in the normal rectal mucosa, gradually defective in TM and carcinoma tissue (P < 0.05). The range of TM with MTS1 negative cases was prominently larger than that with MTS1 positive cases (P < 0.05). CONCLUSIONS The inactivation of MTS1 gene is relative to the occurrence of rectal carcinoma, suggesting that the TM adjacent to rectal carcinoma possess as certain potential malignancy. TM is related to MTS1 gene expression deficit of rectal carcinoma, showing that MTS1 gene expression deficit or mutation may be a factor inducing transitional change adjacent to carcinoma.
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275
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Abstract
The authors describe a 7-year-old Chinese-American female with a germinoma of the basal ganglia who presented with progressive hemiparesis and cerebral hemiatrophy. The additional finding of markedly elevated antiphospholipid antibodies suggests the possibility of an autoimmune pathogenesis for the progressive cerebral atrophy, as well as the later development of cognitive decline, tics, and obsessive-compulsive behaviors.
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