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Chen CF, Lang SY, Zuo PP, Yang N, Wang XQ, Xia C. Effects of D-galactose on the expression of hippocampal peripheral-type benzodiazepine receptor and spatial memory performances in rats. Psychoneuroendocrinology 2006; 31:805-11. [PMID: 16707226 DOI: 10.1016/j.psyneuen.2006.03.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Revised: 03/14/2006] [Accepted: 03/17/2006] [Indexed: 11/26/2022]
Abstract
The changes in spatial memory performances and the binding of hippocampal peripheral-type benzodiazepine receptor (PBR) induced by D-galactose (D-gal) were investigated in rats. The animals were randomly divided into two groups: saline-treated group and D-gal-induced aging group. All rats received 56 days of injection followed by 5 days of behavioral tests. The D-gal-induced aging rats presented significant impairment in water maze performance, compared with that in the saline-treated rats. A significant decrease in [3H]PK11195 binding in the synaptosomes from hippocampus in the D-gal-induced aging rats was observed, compared to that in the saline-treated rats. Meanwhile, the Scatchard analysis revealed that there was a decrease in Bmax, with no significant change in KD. Further analysis demonstrated that water maze performance was closely related to the PK11195 binding in all rats. These results suggest that D-gal decreased the density of PBR in hippocampal synaptosomes, which may be attributable to the progressive pathogenesis of aging in rats.
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Fang Q, Liu X, Abe S, Kobayashi T, Wang XQ, Kohyama T, Hashimoto M, Wyatt T, Rennard SI. Thrombin induces collagen gel contraction partially through PAR1 activation and PKC-epsilon. Eur Respir J 2005; 24:918-24. [PMID: 15572532 DOI: 10.1183/09031936.04.00005704] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The ability of fibroblasts to contract three-dimensional collagen gels has been used as an in vitro model of the tissue contraction which characterises both normal repair and fibrosis. Among its actions, thrombin can activate the protease-activated receptor (PAR)1 and, thereby, stimulate inflammation and repair. The current study evaluated whether thrombin could stimulate fibroblast-mediated collagen gel contraction by activating PAR1 and whether its downstream signalling depends on protein kinase C (PKC)-epsilon. Human foetal lung fibroblasts (HFL-1) were cultured in three-dimensional collagen gels and the area of the gels was measured by image analyser. Both thrombin and TFLLR, a selective PAR1 agonist, stimulated collagen gel contraction mediated by HFL-1. After RNA interference-mediated PAR1 knockdown in HFL-1, both thrombin and the PAR1 agonist-induced gel contraction were partially inhibited (by 22.4+/-2.2% and 17.6+/-5.6%, respectively). The gel contraction stimulated by thrombin was also reduced by a nonspecific PKC inhibitor and a calcium-independent PKC-epsilon inhibitor. Both thrombin and TFLLR significantly increased PKC-epsilon activity, and this effect was blocked by PAR1 knockdown. Thrombin stimulates collagen gel contraction at least partially through activation of protease-activated receptor 1 and protein kinase C-epsilon, and may contribute to tissue remodelling in inflammatory airway and lung diseases.
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128
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Wang XQ, Wang M, Li ZH, Xu YB, He PM. Modeling and calculation of field emission enhancement factor for carbon nanotubes array. Ultramicroscopy 2005; 102:181-7. [PMID: 15639348 DOI: 10.1016/j.ultramic.2004.08.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Revised: 08/05/2004] [Accepted: 08/24/2004] [Indexed: 11/15/2022]
Abstract
To estimate the apex field enhancement factor associated with carbon nanotubes (CNTs) array on a planar cathode surface, the image model of floated sphere between parallel anode and cathode plates was proposed. Firstly, the field enhancement factor of individual CNT was given as the following expression, beta0=h/rho+3.5, where h is the height and rho is the radius of CNTs. Then the field enhancement factor of CNTs array was discussed and the above expression was modified to be beta=h/rho+3.5-W, in which W is the function of the intertube distance R and represents the coulomb field interaction between the CNTs. All results show that the intertube distance of CNTs array critically affects the field emission. When the intertube distance is less than the height of tube, the field enhancement factor will decrease rapidly with decreasing the intertube distance. According to the calculated results and considering the field emission current density, the filed emission is optimal theoretically when the intertube distance is comparable with the height of CNTs.
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Li HX, Lei DS, Wang XQ, Skog S, He Q. Serum thymidine kinase 1 is a prognostic and monitoring factor in patients with non-small cell lung cancer. Oncol Rep 2005; 13:145-9. [PMID: 15583816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
Thymidine kinase 1 (TK1) is a pyrimidine metabolic pathway enzyme involved in salvage DNA synthesis and thus, a cell cycle-dependent marker. We have developed anti-TK1 monoclonal/polyclonal Abs raised against a 15-amino acid synthetic peptide (KPGEAVAARKLFAPQ) corresponding to part of the C-terminus of human TK1. These Abs are useful for both serological and immunohistochemical detection of TK1 in a number of cancer diseases. In this study we examined TK1 concentration in serum (STK1) in 250 preoperative non-small cell lung cancer patients (NSCLC), including 188 non-metastatic (group M0) and 62 metastatic patients (group M1). Serum from 16 healthy individuals was used as controls. The concentration of STK1 of preoperative NSCLC patients was significantly higher than STK1 of healthy individuals (p<0.0001). In group M0, preoperative STK1 concentration was significantly higher in patients of tumour size T2, as compared to tumour size T1 (p=0.042), and in T3-T4, as compared to T1-T2 (p=0.01). No significant difference in STK1 concentration between patients of tumour stage I and stage II (p=0.057) were found, but significantly higher STK1 concentration in patients of stage III, as compared stage I-II (p=0.025). No significant difference of STK1 concentration were found in patients of group M1 concerning tumour size or tumour stage, or between patients with adenocarcinomas (AC) and squamous cell carcinomas (SCC). We studied the changes of STK1 concentration individually one month after operation in metastatic subjects (group M1, n=19) and in tumour-free subjects (group M0, n=38). In the M0 group, the concentration of STK1 one month after operation was significantly decline by 45%, when comparing to concentrations of STK1 preoperative (p<0.001). In the group M1, however, no significant decrease in STK1 concentrations were found one month after operation. We conclude that STK1 has prognostic value and is a reliable marker for monitoring the response to surgery of NSCLC patients.
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Luo HG, Xiang T, Wang XQ, Su ZB, Yu L. Fano resonance for Anderson impurity systems. PHYSICAL REVIEW LETTERS 2004; 92:256602. [PMID: 15245042 DOI: 10.1103/physrevlett.92.256602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2003] [Indexed: 05/24/2023]
Abstract
We present a general theory for the Fano resonance in Anderson impurity systems. It is shown that the broadening of the impurity level leads to an additional and important contribution to the Fano resonance around the Fermi surface, especially in the mixed valence regime. This contribution results from the interference between the Kondo resonance and the broadened impurity level. Being applied to the scanning tunneling microscopic experiments, we find that our theory gives a consistent and quantitative account for the Fano resonance line shapes for both Co and Ti impurities on Au or Ag surfaces. The Ti systems are found to be in the mixed valence regime.
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Yamakawa J, Takahashi T, Saegusa S, Moriya J, Itoh T, Kusaka K, Kawaura K, Wang XQ, Kanda T. Effect of the Serotonin Blocker Sarpogrelate on Circulating Interleukin-18 Levels in Patients with Diabetes and Arteriosclerosis Obliterans. J Int Med Res 2004; 32:166-9. [PMID: 15080020 DOI: 10.1177/147323000403200209] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We aimed to evaluate the effect of treatment with sarpogrelate, a serotonin 2A receptor antagonist, on circulating interleukin (IL)-18 levels in patients with diabetes and arteriosclerosis obliterans. Patients received sarpogrelate (100 mg 3 times daily) for 2 months. We evaluated the degree of cryaesthesia (a feeling of cold in the foot and toes) as the clinical outcome, and measured circulating IL-18, IL-6 and lipid protein concentrations. An improvement in clinical outcome occurred after initiation of sarpogrelate therapy;a significant decrease in IL-18 levels was observed after 2 months of therapy. Levels of IL-6 and lipid proteins, including triglyceride, total cholesterol and high-density lipoprotein cholesterol, were not significantly altered by treatment. Our data suggest that by reducing circulating IL-18 levels, sarpogrelate treatment may contribute to the inhibition of arteriosclerosis obliterans progression in patients with diabetes.
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Luo HG, Xiang T, Wang XQ. Comment on "Time-dependent density-matrix renormalization group: a systematic method for the study of quantum many-body out-of-equilibrium systems". PHYSICAL REVIEW LETTERS 2003; 91:049701-049702. [PMID: 12906705 DOI: 10.1103/physrevlett.91.049701] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2002] [Indexed: 05/24/2023]
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133
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Zhao JZ, Wang XQ, Xiang T, Su ZB, Yu L. Effects of the Dzyaloshinskii-Moriya interaction on low-energy magnetic excitations in copper benzoate. PHYSICAL REVIEW LETTERS 2003; 90:207204. [PMID: 12785925 DOI: 10.1103/physrevlett.90.207204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2002] [Indexed: 05/24/2023]
Abstract
We have investigated the physical effects of the Dzyaloshinskii-Moriya (DM) interaction in copper benzoate. In the low-field limit, the spin gap is found to vary as H(2/3)ln((1/6)(J/mu(B)H(s)) (H(s): an effective staggered field induced by the external field H) in agreement with the prediction of conformal field theory, while the staggered magnetization varies as H(1/3) and the ln((1/3)(J/mu(B)H(s)) correction predicted by conformal field theory is not confirmed. The linear scaling relation between the momentum shift and the magnetization is broken. We have determined the coupling constant of the DM interaction and have given a complete quantitative account for the field dependence of the spin gaps along all three principal axes, without resorting to additional interactions such as interchain coupling. A crossover to strong applied field behavior is predicted for further experimental verification.
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Vaziri ND, Wang XQ, Ni ZN, Kivlighn S, Shahinfar S. Effects of aging and AT-1 receptor blockade on NO synthase expression and renal function in SHR. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1592:153-61. [PMID: 12379478 DOI: 10.1016/s0167-4889(02)00309-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In an earlier study, we found increased NO production and NO synthase (NOS) expression in renal and vascular tissues of prehypertensive and adult spontaneously hypertensive rats (SHR). This study was designed to determine the effects of aging and AT-1 receptor blockade (losartan 30 mg/kg/day beginning at 8 weeks of age) on NO system in this model. Compared to the Wistar Kyoto (WKY) control rats, untreated SHR showed severe hypertension, elevated urinary NO metabolite (NO(chi)) excretion, marked upregulations of renal and vascular eNOS and iNOS proteins, normal renal function and heart weight at 9 weeks of age. Hypertension control with either AT-1 receptor or calcium channel blockade (felodipine 5 mg/kg/day) mitigated upregulation of NOS isoforms in the young SHR. With advanced age (63 weeks), the untreated SHR showed increased proteinuria, renal insufficiency, cardiomegaly, reduced urinary NO(chi) excretion and depressed renal and vascular NOS protein expressions as compared to the corresponding WKY group. AT-1 receptor blockade prevented proteinuria, renal insufficiency, cardiomegaly, and renal and vascular NOS deficiency. Thus, in young SHR, hypertension results in compensatory upregulation of renal and vascular NOS, which can be attenuated by vigorous antihypertensive therapy. With advanced age, untreated SHR exhibit cardiomegaly, renal dysfunction and marked reductions of eNOS and iNOS compared with the aged WKY rats. Hypertension control with AT-1 receptor blockade initiated early in the course of the disease prevents target organ damage and preserves renal and vascular NOS.
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135
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Irvine AD, Sun P, Kos L, Wang XQ, Paller AS. A colorimetric bead-binding assay for detection of intermolecular interactions. Exp Dermatol 2002; 11:462-7. [PMID: 12366700 DOI: 10.1034/j.1600-0625.2002.110510.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We have developed a new technique that rapidly and reproducibly allows direct visualization of molecular interactions, including receptor-ligand binding. The technique can be easily applied to examine binding between proteins and glycoproteins, or proteins and glycolipids, including gangliosides. In this novel bead-binding assay, the suspected 'ligand' molecule is bound to 0.2- or 1.0- micro m colored FluoSphere beads. These coated beads are then mixed directly with 150- micro m Sepharose or 50- to 75- micro m agarose beads coated with the second 'target' molecule. Binding between molecules is easily detected by immunofluoresence microscopy as colored rosettes or aggregations formed by clustering of the smaller fluorescent beads around the larger non-fluorescent bead. The validity of this technique for glycolipid binding to protein was verified through demonstration of the known interaction between the beta subunit of cholera toxin with ganglioside GM1. The bead-binding technique facilitated the novel observations of interaction between ganglioside GT1b with the alpha5 subunit of alpha5beta1 integrin and the interaction of GM3 with the epidermal growth factor receptor. A modification of this technique, in which the coated beads are bound to protein fixed on plates, allows a quantifiable colorimetric assay of interaction. This versatile and rapid technique will have widespread applications for in vitro systems and may also be useful for in vivo analysis of binding to cell surface receptor molecules.
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136
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Wang XQ, Fang J, Nunez AA, Clemens LG. Developmental exposure to polychlorinated biphenyls affects sexual behavior of rats. Physiol Behav 2002; 75:689-96. [PMID: 12020734 DOI: 10.1016/s0031-9384(02)00673-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Polychlorinated biphenyls (PCBs) are persistent environmental contaminants that have the potential to disrupt reproduction through a variety of different pathways. In the present study, we investigated the effects of fetal and lactational PCB exposure on reproductive behavior in male and female laboratory rats. These pregnant rats were injected daily with either 2,4,2',4'-tetrachlorobiphenyl (PCB 47) at the dosage of 1 or 20 mg/kg body weight or 3,4,3',4'-tetrachlorobiphenyl (PCB 77) at the dosage of 0.25 or 1 mg/kg body weight or sesame oil (control group) from gestational days 7 to 18. Offspring were then tested for sexual behavior as adults. Exposure to both PCB 77 and PCB 47 reduced the level of sexual receptivity in the female offspring, but had no detectable effects on the sexual behavior of the male offspring. In addition to changes in adult sexual behavior in the females, both PCBs produced a significant increase in the females' anogenital distance, suggesting a modification of androgen responsiveness in females resulting from PCB exposure during development. Similar effects were not seen with the males.
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Xiao AY, Homma M, Wang XQ, Wang X, Yu SP. Role of K(+) efflux in apoptosis induced by AMPA and kainate in mouse cortical neurons. Neuroscience 2002; 108:61-7. [PMID: 11738131 DOI: 10.1016/s0306-4522(01)00394-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Activation of ionotropic glutamate receptors can induce neuronal apoptosis in vitro and in vivo. We showed previously that activation of the N-methyl-D-aspartic acid (NMDA) subtype of glutamate receptors in a low Ca(2+) and low Na(+) condition induced apoptotic neuronal death, and that the K(+) efflux via NMDA receptor channels was likely a key event in NMDA-induced apoptosis. Since non-NMDA receptors, alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) and kainate receptors, are also permeable to K(+), we tested the hypothesis that stimulating K(+) efflux via non-NMDA receptor channels could induce apoptosis in cultured cortical neurons. Using a Ca(2+)-free and Na(+)-free external solution, application of kainate revealed outward membrane currents carried by K(+) efflux. In a low Ca(2+)/low Na(+) medium, a 5-h exposure to 50-500 microM AMPA in the presence of the NMDA receptor antagonist MK801 induced dose-dependent neuronal death 24 h after the onset of the insult, accompanied by intracellular K(+) reduction and caspase-3 activation. The AMPA-induced cell death was attenuated by the caspase inhibitor Z-Val-Ala-Asp(OMe)-fluoromethyl ketone (Z-VAD-FMK) and by the protein synthesis inhibitor cycloheximide. Reducing K(+) efflux by raising extracellular K(+) concentration from 5 to 25 mM attenuated AMPA-triggered cell death, the Ca(2+) channel antagonist nifedipine showed no effect on the AMPA toxicity. Kainate induced similar neuronal death sensitive to attenuation by Z-VAD-FMK or elevated extracellular K(+).We suggest that the non-NMDA receptor-mediated K(+) efflux may participate in apoptotic process and that blocking excessive K(+) efflux mediated by NMDA and non-NMDA receptors may selectively prevent neuronal apoptosis under certain pathological conditions.
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138
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Mancini MJ, Connors AF, Wang XQ, Nock S, Spencer C, Mccullough C, Lobo P, Isaacs R. HLA matching for simultaneous pancreas-kidney transplantation in the United States: a multivariable analysis of the UNOS data. Clin Nephrol 2002; 57:27-37. [PMID: 11837799 DOI: 10.5414/cnp57027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND As the incidence of diabetic nephropathy increases, especially in minority populations, more simultaneous pancreas-kidney (SPK) transplants are being performed both in the United States and worldwide. The role of matching on SPK outcomes and organ allocation remains controversial. The purpose of this analysis was to determine the influence of HLA matching using currently employed criteria on 5-year SPK graft survival. METHODS We performed an analysis of all 3,316 SPK transplants performed in the United States reported to the United Network for Organ Sharing (UNOS) between December 31, 1988 and December 31, 1994. Kaplan-Meier unadjusted 1- and 5-year graft survival with log rank comparisons and Cox multivariable regression models that adjusted for 12 confounding variables were used to analyze the influence of HLA matching on outcomes. RESULTS Despite low-grade HLA or DR matching or high levels of common reactive groups (CREG) mismatching, 1- and 5-year allograft survival rates were 90% and 78% for kidney, and 85% and 75% for pancreas transplantation. CONCLUSIONS SPK transplantation is associated with excellent outcomes independent of the level of HLA matching. These data support the hypothesis that SPK transplants need not be allocated based on matching criteria, thus minimizing organ ischemia time and promoting a more racially equitable allocation for SPKs in the US today.
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139
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Lin TS, Nriagu J, Wang XQ. Thallium concentration in lake trout from Lake Michigan. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2001; 67:921-925. [PMID: 11692209 DOI: 10.1007/s001280209] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2000] [Accepted: 08/07/2001] [Indexed: 05/23/2023]
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140
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Wang XQ, Sun P, Paller AS. Inhibition of integrin-linked kinase/protein kinase B/Akt signaling: mechanism for ganglioside-induced apoptosis. J Biol Chem 2001; 276:44504-11. [PMID: 11577096 DOI: 10.1074/jbc.m106563200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ganglioside GT1b inhibits keratinocyte attachment to and migration on a fibronectin matrix by binding to alpha(5)beta(1) and preventing alpha(5)beta(1) interaction with fibronectin. The role of gangliosides in triggering keratinocyte apoptosis, however, is unknown. Addition of GT1b to keratinocyte-derived SCC12 cells, grown in serum-free medium but exposed to fibronectin, suppressed Bad phosphorylation, activated caspase-9, and inhibited cyclin D and E expression, resulting in cell cycle arrest at G(1) phase and initiation of apoptosis. The mechanism of GT1b activation of caspase-9 involved inhibition of beta(1) integrin serine/threonine phosphorylation and decreased phosphorylation of both integrin-linked kinase and protein kinase B/Akt at its Ser-473 site, leading to cytochrome c release from mitochondria. Consistently, blockade of GT1b function with anti-GT1b antibody specifically activated the Ser-473 site of Akt, markedly suppressing apoptosis. The ganglioside-induced inhibition of Akt phosphorylation was GT1b-specific and was not observed when cells were treated with other keratinocyte gangliosides, including GD3. These studies suggest that the modulation of keratinocyte cell cycle and survival by GT1b is mediated by its direct interaction with alpha(5)beta(1) and resultant inhibition of the integrin/integrin-linked kinase/protein kinase B/Akt signaling pathway.
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He XY, Wang XQ, Yang SJ, Chang WR, Liang DC. Overexpression, purification, crystallization and preliminary crystallographic studies on a thermostable beta-glycosidase from Thermus nonproteolyticus HG102. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2001; 57:1650-1. [PMID: 11679733 DOI: 10.1107/s090744490101112x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2001] [Accepted: 07/03/2001] [Indexed: 11/10/2022]
Abstract
A thermostable beta-glycosidase (Tn-gly) from Thermus nonproteolyticus HG102 has been cloned and overexpressed in Escherichia coli. The recombinant enzyme, with a molecular mass of 48.9 kDa, was purified to homogeneity. It can hydrolyze a wide range of oligosaccharides and perform transglycosylation. Crystals of the recombinant enzyme were grown by the hanging-drop vapour-diffusion technique with MPD and NaCl as precipitants. They belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 66.7, b = 94.6, c = 176.5 A.
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Wang QW, Wang XQ, Wang F, Li ZW. [Modulation of SKF38393 and clonidine on expressed GABA(A) receptors in Xenopus oocytes]. ZHONGGUO YING YONG SHENG LI XUE ZA ZHI = ZHONGGUO YINGYONG SHENGLIXUE ZAZHI = CHINESE JOURNAL OF APPLIED PHYSIOLOGY 2001; 17:333-336. [PMID: 21207691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
AIM AND METHODS The present research is performed on Xenopus oocytes injected with rat DRG mRNA. Modulatory effects of SKF38393 and Clonidine on GABAS(A) receptors expressed in Xenopus oocytes was investigated by two-electrodes voltage-clamp technique, and it is compared with the neurons fresh isolated. RESULTS It is found that SKF38393 and Clonidine inhibitable GABA(A) receptor function obviously by a concentration-dependent manner. There is an interaction between SKF38393- and Clonidine-induced currents. The inhibition of SKF38393 and Clonidine on GABA(A) receptors is noncompetitive and voltage-independent. CONCLUSIONS The results suggest that the inhibition by SKF38393 and clonidine of GABA-activated current might be a result of phosphorylation of GABA(A) receptor following action of second messenger and the thereby mediated intracellular transduction.
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Parkerson GR, Harrell FE, Hammond WE, Wang XQ. Characteristics of adult primary care patients as predictors of future health services charges. Med Care 2001; 39:1170-81. [PMID: 11606871 DOI: 10.1097/00005650-200111000-00004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Utilization risk assessment is potentially useful for allocation of health care resources, but precise measurement is difficult. OBJECTIVE Test the hypotheses that health-related quality of life (HRQOL), severity of illness, and diagnoses at a single primary care visit are comparable case-mix predictors of future 1-year charges in all clinical settings within a large health system, and that these predictors are more accurate in combination than alone. RESEARCH DESIGN Longitudinal observational study in which subjects' characteristics were measured at baseline, and their outpatient clinic visits and charges and their inpatient hospital days and charges were tracked for 1 year. SUBJECTS Adult primary care patients. MEASURES Duke Health Profile for HRQOL, Duke Severity of Illness Checklist for severity of illness, and Johns Hopkins Ambulatory Care Groups for diagnostic groups classification. RESULTS Of 1,202 patients, 84.4% had follow up in the primary care clinic, 63.2% in subspecialty clinics, 14.8% in the emergency room, and 9.6% in the hospital. Of $6,290,775 total charges, $779,037 (12.2%) was for follow-up primary care. The highest accuracy was found for predicting primary care charges, where R2 for predictors ranged from 0.083 for medical record auditor-reported severity of illness to 0.107 for HRQOL. When predictors were combined, the highest R2 of 0.125 was found for the combination of HRQOL and diagnostic groups. CONCLUSIONS Baseline HRQOL, severity of illness, and diagnoses were comparable predictors of 1-year health services charges in all clinical sites but most predictive for primary care charges, and were more accurate in combination than alone.
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Assmann SM, Wang XQ. From milliseconds to millions of years: guard cells and environmental responses. CURRENT OPINION IN PLANT BIOLOGY 2001; 4:421-428. [PMID: 11597500 DOI: 10.1016/s1369-5266(00)00195-3] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
During the past year, significant advances have been made in our understanding of stomatal development and its response to climate change, and in our knowledge of how guard cell Ca(2+) oscillations encode environmental signals. Recent studies on (de)phosphorylation mechanisms have provided new information on how guard cells respond to abscisic acid and blue light.
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Shi HB, Shao CL, Wang XQ, Yu ZL. [Analysis of the spectrum of damage effects of low energy N+ ions on cytosine aqueous solution]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2001; 21:644-646. [PMID: 12945319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Low energy N+ ions were produced by gas arc-discharge and the ions were accelerated into cytosine (C) aqueous solution. Changes in UV and infrared spectra of C after this kind of ions' action were investigated. UV spectra showed that absorption at 259 nm gradually decreased and lambda max of C solution moved toward the longer wavelength with the time. Thus, it was deduced that C was damaged and some fragments including -NO2 and -NH2 groups might have been produced. Judging from the IR spectra, the disappearance of the peak of 3,005 cm-1 confirmed the formation of -NO2 groups. All these results revealed that N+ ions caused various damages on C molecules and many new substances were formed. These new substances were not synthesized only by combination of the damage fragments in the solution, but also by "deposition" of N+ from outside.
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Manzerra P, Behrens MM, Canzoniero LM, Wang XQ, Heidinger V, Ichinose T, Yu SP, Choi DW. Zinc induces a Src family kinase-mediated up-regulation of NMDA receptor activity and excitotoxicity. Proc Natl Acad Sci U S A 2001; 98:11055-61. [PMID: 11572968 PMCID: PMC58682 DOI: 10.1073/pnas.191353598] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Zinc is coreleased with glutamate from excitatory nerve terminals throughout the central nervous system and acutely inhibits N-methyl-d-aspartate (NMDA) receptor activation. Here we report that cultured murine cortical neurons briefly exposed to sublethal concentrations of zinc developed increased intracellular free Na(+), phosphorylation of Src kinase at tyrosine 220, and tyrosine phosphorylation of NMDA receptor 2A/2B subunits, in a fashion sensitive to the Src family kinase inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine, PP2. Functionally, this zinc exposure produced a delayed increase in NMDA receptor current in perforated patch but not conventional whole-cell recordings, as well as an increase in NMDA receptor-mediated cell death. These observations suggest that the effect of synaptically released zinc on neuronal NMDA receptors may be biphasic: acute block, followed by Src family kinase-mediated up-regulation of NMDA receptor activity and cytotoxicity.
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147
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Gole LA, Wong PF, Ng PL, Wang XQ, Ng SC, Bongso A. Does sperm morphology play a significant role in increased sex chromosomal disomy? A comparison between patients with teratozoospermia and OAT by FISH. JOURNAL OF ANDROLOGY 2001; 22:759-63. [PMID: 11545287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Eight semen samples from men with teratozoospermia (T), along with samples from 3 men with normal fertility and 5 samples from men with oligoasthenoteratozoospermia (OAT) were analyzed for X and Y chromosomal anomalies with the use of fluorescently labeled centromeric probes. This study was undertaken to determine whether patients with abnormal sperm morphology (teratozoospermia) have increased or decreased incidence of a sex chromosomal anomaly. The sex chromosome disomy for the T samples was 0.36% and for the OAT group it was 0.61%, compared with baseline value for the normozoospermia group (0.09%).
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148
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Wang XQ, Guo YJ, Yang CS. [Determination of shikimic acid in fruit of Illiciaceae plants by HPLC with diode-array detection]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2001; 26:447-9. [PMID: 12776355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
OBJECTIVE To establish the determination method of Shikimic acid. METHOD Using HPLC method as the determination method. The separation was performed in a SiO2-NH2 column with a mobile phase of Acetonitrile-2% H3PO4 water solution (95:5); The sample wavelength was 213 nm, reference wavelength 300 nm. RESULT The average collection was 98.5%, RSD 1.67% (n = 5). CONCLUSION This method is suitable for the determination of Shkimic acid in herb medicines and preparation containing shikimic acid.
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149
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Wang XQ, Sun P, O'Gorman M, Tai T, Paller AS. Epidermal growth factor receptor glycosylation is required for ganglioside GM3 binding and GM3-mediated suppression [correction of suppresion] of activation. Glycobiology 2001; 11:515-22. [PMID: 11447130 DOI: 10.1093/glycob/11.7.515] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Gangliosides are able to bind to the epidermal growth factor receptor and inhibit its activation, but the mechanism of this inhibition is unknown. To address the role of receptor carbohydrates in facilitating interaction with gangliosides, we examined the ability of GM3 to bind the deglycosylated receptor and inhibit its autophosphorylation. Flow cytometry studies demonstrated that deglycosylation of the receptor did not affect its ability to be transported to the cell membrane. In contrast with the native (fully glycosylated) receptor, GM3 did not coimmunoprecipitate with the deglycosylated receptor. Using a novel colorimetric bead binding assay, GM3 was shown to bind well to the immunoprecipitated native receptor but not at all to the deglycosylated receptor. Finally, the addition of GM3 to cells with deglycosylated epidermal growth factor receptors did not result in significant further inhibition of autophosphorylation of the receptor, despite a 10-fold decrease in phosphorylation of the native epidermal growth factor receptor by 200 microM GM3. These studies suggest that ganglioside affects epidermal growth factor receptor activity through a direct interaction that requires receptor glycosylation, and contribute to our understanding of the role of gangliosides in cell membrane function.
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150
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Wang XQ, Jian ZJ, Xie JC. [Changes in plasma concentration of interleukin-6 in elderly patients with coronary artery disease complicated with heart failure]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:231-2. [PMID: 12536690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE The aim of this study was to observe the concentrations of plasma interleukin-6(IL-6) in elderly patients with coronary artery disease(CAD). METHODS Forty-eight CAD patients with heart failure, 15 CAD patients without heart failure, and 30 normal subjects were studied. The plasma concentration of interleukin-6(IL-6) was measured by enzyme-linked immunosorbent assay. RESULTS The plasma concentration of IL-6 in CAD patients with heart failure was significantly higher than that without heart failure and normal subjects, respectively (P < 0.05). There was no significant difference between CAD patients without heart failure and normal subjects in the plasma levels of IL-6. There was a negative correlation between the concentration of IL-6 and left ventricular ejection fraction(LVEF) (r = -0.60, P < 0.01). The plasma concentration of IL-6 of the group with re-hospitalization because of severe heart failure was significantly higher than that of the group without hospital readmission (P < 0.01). CONCLUSION The plasma concentration of IL-6 in CAD patients with heart failure may provide the important information for the severity of the disease and for the prognostic prediction in the disease.
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