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Wei YL, Yang JC, Lin YY, Chuang SY, Wang HP. Recycling of harbor sediment as lightweight aggregate. MARINE POLLUTION BULLETIN 2008; 57:867-872. [PMID: 18471834 DOI: 10.1016/j.marpolbul.2008.03.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 03/14/2008] [Accepted: 03/22/2008] [Indexed: 05/26/2023]
Abstract
Sediment sampled from Taichung Harbor was mixed with local reservoir sediment at different weight ratios to prepare lightweight aggregate at 1050, 1100, and 1150 degrees C. A pressure of 3000 or 5000 psi was used to shape the powder mixtures into pellets before the heating processes. The results indicate that the leaching levels of trace metals from the lightweight aggregate samples are considerably reduced to levels less than Taiwan Environmental Protection Administration regulatory limits. Increasing final process temperature tends to reduce the bulk density and crushing intensity of lightweight aggregate with a concomitant increase in water sorption capability. Lightweight aggregate with the lowest bulk density, 0.49 g cm(-3) for the 5000 psi sample, was obtained with the heating process to 1150 degrees C. Based on the X-ray absorption near edge structure results, FeSO(4) decomposition with a concomitant release of SO(x) (x = 2,3) is suggested to play an important role for the bloating process in present study.
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Tsai CK, Liao CY, Wang HP, Chien YC, Jou CJG. Pyrolysis of spill oils adsorbed on zeolites with product oils recycling. MARINE POLLUTION BULLETIN 2008; 57:895-898. [PMID: 18395757 DOI: 10.1016/j.marpolbul.2008.02.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 02/18/2008] [Accepted: 02/23/2008] [Indexed: 05/26/2023]
Abstract
Experimentally, a feasibility study for adsorption and catalytic pyrolysis of spill oils on Cu/ZSM-5 for recycling of light oils has been conducted in the present work. The adsorption and pyrolysis of model compounds such as heptane, toluene, and diesel (to stimulate the spill oils) on Cu/ZSM-5 have been investigated on a continuous fixed-bed reactor. By component fitted X-ray absorption near edge structural (XANES) spectroscopy, catalytic active species such as metallic copper (Cu) (77-84%) and Cu(2)O (6-7%) are found in the channels of ZSM-5 during pyrolysis of heptane or toluene. Pyrolysis of diesel effected by Cu/ZSM-5 yields gas (C(1)-C(5)) (32%) and light oil (68%) that can be used as auxiliary fuels.
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128
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Hsu YY, Hsiung TL, Paul Wang H, Fukushima Y, Wei YL, Chang JE. Photocatalytic degradation of spill oils on TiO(2) nanotube thin films. MARINE POLLUTION BULLETIN 2008; 57:873-876. [PMID: 18420225 DOI: 10.1016/j.marpolbul.2008.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 03/02/2008] [Accepted: 03/04/2008] [Indexed: 05/26/2023]
Abstract
The nitrogen-doped TiO(2) nanotube (N-TNT) thin films were synthesized using ZnO nanorods as the template and doped with urea at 623K. Under ultraviolet (UV) and visible light irradiation, the efficiencies for photocatalytic degradation of methylene blue is as high as 30%. About 10% of toluene (representing aromatics in the spill oils) in sea water can be photocatalytically degraded under visible light radiation for 120 min. The aliphatic model compound (1-hexadecene) has, on the contrary, a less efficiency (8%) on the N-TNT photocatalyst. On the average, under visible light radiation, the effectnesses of the N-TNT for photocatalytic degradation of model compounds in the spill oils in sea water are 0.38 mg toluene/gN-TNTh and 0.25 mg 1-hexadecene/gN-TNTh. It is expected that spill oils in the harbors or seashores can be adsorbed and photocatalytically degraded on the N-TNT thin films that are coated onto levee at the sea water surface level.
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Chien YC, Wang HP, Liu SH, Hsiung TL, Tai HS, Peng CY. Photocatalytic decomposition of CCl4 on Zr-MCM-41. JOURNAL OF HAZARDOUS MATERIALS 2008; 151:461-4. [PMID: 17659831 DOI: 10.1016/j.jhazmat.2007.06.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 06/05/2007] [Accepted: 06/06/2007] [Indexed: 05/16/2023]
Abstract
Photocatalytic decomposition of CCl4 (80 mg L(-1) in H2O) effected by Zr-MCM-41 (Zr incorporated in the amorphous wall of MCM-41) has been studied in the present work. Experimentally, photocatalytic decomposition of CCl4 on Zr-MCM-41 was enhanced by about 1.96 times over that on ZrO2. Photocatalytic decomposition of CCl4 may proceed via a two-electron transfer process that yields mainly CHCl3, Cl- and H2. Since little C2Cl2, C2Cl6 or CH2Cl2 was found, it is unlikely that CHCl3 involved in the secondary photocatalytic degradation process. In addition, photocatalytic splitting of H2O on Zr-MCM-41 was also enhanced. The yield of H2 was 6.5 mmol(gZrO2)(-1). About 68% of this hydrogen (6.5 mmol(gZrO2)(-1)) was consumed in the photocatalytic decomposition of CCl4.
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Sun YP, Li XQ, Zhang WX, Wang HP. A method for the preparation of stable dispersion of zero-valent iron nanoparticles. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2007.05.029] [Citation(s) in RCA: 229] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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131
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Chou CT, Liao HT, Chen CH, Chen WS, Wang HP, Su KY. The Clinical Application of Anti-CCP in Rheumatoid Arthritis and Other Rheumatic Diseases. Biomark Insights 2007; 2:165-71. [PMID: 19662201 PMCID: PMC2717818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Rheumatoid arthritis (RA) is a common rheumatic disease in Caucasians and in other ethnic groups. Diagnosis is mainly based on clinical features. Before 1998, the only serological laboratory test that could contribute to the diagnosis was that for rheumatoid factor (RF). The disease activity markers for the evaluation of clinical symptoms or treatment outcome were the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). As a matter of fact, the diagnosis of early RA is quite impossible, as the clinical criteria are insufficient at the beginning stage of the disease. In 1998, Schelleken reported that a high percentage of RA patients had a specific antibody that could interact with a synthetic peptide which contained the amino acid citrulline. The high specificity (98%) for RA of this new serological marker, anti-cyclic citrullinated antibody (anti-CCP antibody), can be detected early in RA, before the typical clinical features appear. The presence or absence of this antibody can easily distinguish other rheumatic diseases from RA. Additionally, the titer of anti-CCP can be used to predict the prognosis and treatment outcome after DMARDs or biological therapy. Therefore, with improvement of sensitivity, the anti-CCP antibody will be widely used as a routine laboratory test in the clinical practice for RA.
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Liu SH, Yan NQ, Liu ZR, Qu Z, Wang HP, Chang SG, Miller C. Using bromine gas to enhance mercury removal from flue gas of coal-fired power plants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:1405-12. [PMID: 17593749 DOI: 10.1021/es061705p] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Bromine gas was evaluated for converting elemental mercury (Hg0) to oxidized mercury, a form that can readily be captured by the existing air pollution control device. The gas-phase oxidation rates of Hg0 by Br2 decreased with increasing temperatures. SO2, CO, HCl, and H2O had insignificant effect, while NO exhibited a reverse course of effect on the Hg0 oxidation: promotion at low NO concentrations and inhibition at high NO concentrations. A reaction mechanism involving the formation of van der Waals clusters is proposed to accountfor NO's reverse effect. The apparent gas-phase oxidation rate constant, obtained under conditions simulating a flue gas without flyash, was 3.61 x 10(-17) cm3 x molecule(-1) x s(-1) at 410 K corresponding to a 50% Hg0 oxidation using 52 ppm Br2 in a reaction time of 15 s. Flyash in flue gas significantly promoted the oxidation of Hg0 by Br2, and the unburned carbon component played a major role in the promotion primarily through the rapid adsorption of Br2 which effectively removed Hg0 from the gas phase. At a typical flue gas temperature, SO2 slightly inhibited the flyash-induced Hg0 removal. Conversely, NO slightly promoted the flyash induced Hg0 removal by Br2. Norit Darco-Hg-LH and Darco-Hg powder activated carbons, which have been demonstrated in field tests, were inferred for estimating the flyash induced Hg0 oxidation by Br2. Approximately 60% of Hg0 is estimated to be oxidized with the addition of 0.4 ppm of gaseous Br2 into full scale power plant flue gas.
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Chen CC, Lee TC, Liu KL, Lin JT, Wang HP. Pus from the pylorus: an unusual endoscopic finding suggestive of periduodenal abscess. Endoscopy 2007; 39 Suppl 1:E235-6. [PMID: 17674289 DOI: 10.1055/s-2006-944900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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134
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Chang CY, Tu CH, Chiang TS, Wang HP. Acute gastric ulcer associated with gamma knife treatment (conformal stereotactic radiotherapy) of recurrent hepatocellular carcinoma. Endoscopy 2007; 39 Suppl 1:E154. [PMID: 16673314 DOI: 10.1055/s-2006-925190] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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135
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Hsiao MC, Wang HP, Chang JE, Peng CY. Tracking of copper species in incineration fly ashes. JOURNAL OF HAZARDOUS MATERIALS 2006; 138:539-42. [PMID: 16839673 DOI: 10.1016/j.jhazmat.2006.05.087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Revised: 05/25/2006] [Accepted: 05/26/2006] [Indexed: 05/10/2023]
Abstract
Speciation of copper in the incineration waste heat boiler (HB) and the down stream electrostatic precipitator (EP) fly ashes during the flue gas cooling down (1123-->473 K) has been studied by X-ray absorption near edge structural (XANES) spectroscopy in the present work. Copper species such as Cu(OH)(2) (59-67%), CuCl(2) (5-12%), CuO (24-26%), and a small amount of CuS (3-4%) in fly ashes were determined by semi-quantitative analyses of the XANES spectra. In the toxicity characteristics leaching procedure (TCLP) tests, about 83 and 20% of copper were leached from the EP and HB fly ashes, respectively. The relatively high leachability of copper for the EP fly ash might be due to the fact that CuCl(2) was enriched on the surfaces as observed by X-ray photoelectron spectroscopy (XPS). On the contrary, CuCl(2) was mainly encapsulated in the HB fly ashes.
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Wei YL, Wang HC, Paul Wang H. Effect of heating on speciation of copper in Si/Al/Ca-based environmental matrices. Radiat Phys Chem Oxf Engl 1993 2006. [DOI: 10.1016/j.radphyschem.2005.10.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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137
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Huang HL, Wang HP, Wei YL, Jou C, Lu WC, Chang JI. Speciation of chromium in swarf during pyrolysis. Radiat Phys Chem Oxf Engl 1993 2006. [DOI: 10.1016/j.radphyschem.2005.10.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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138
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Huang HL, Wang HP, Wei GT, Sun IW, Huang JF, Yang YW. Extraction of nanosize copper pollutants with an ionic liquid. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:4761-4. [PMID: 16913135 DOI: 10.1021/es060034s] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Speciation and possible reaction paths of nanosize copper pollutants extracted with a RTIL (room-temperature ionic liquid ([C4mim][PF6], 1-butyl-3-methylimidazolium hexafluorophosphate)) have been studied in the present work. Experimentally, in a very short contact time (2 min), 80-95% of nanosize CuO as well as other forms of copper (such as nanosize Cu, Cu2+, or Cu(II)(ads) (in the channels of MCM-41)) in the samples could be extracted into the RTIL. The main copper species extracted in the RTIL as observed by XANES (X-ray absorption near edge structure) were Cu(II). Existence of Cu-N bondings with coordination numbers (CNs) of 3-4 for copper extracted in the RTIL was found by EXAFS (extended X-ray absorption fine structural) spectroscopy. Interestingly, chelation of Cu(II) with 1-methylimidazole (MIm) in the RTIL during extraction was also observed by 1H NMR (nuclear magnetic resonance). At least two possible reaction paths for the rapid extraction of nanosize copper pollutants with the RTIL might occur: (1) an enhanced dissolution of nanosize CuO (to form Cu2+) and (2) formation of [Cu(MIm)4(H2O)2]2+ that acted as a carrier of copper into the RTIL matrix.
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Sun YP, Li XQ, Cao J, Zhang WX, Wang HP. Characterization of zero-valent iron nanoparticles. Adv Colloid Interface Sci 2006; 120:47-56. [PMID: 16697345 DOI: 10.1016/j.cis.2006.03.001] [Citation(s) in RCA: 425] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Accepted: 03/01/2006] [Indexed: 11/18/2022]
Abstract
The iron nanoparticle technology has received considerable attention for its potential applications in groundwater treatment and site remediation. Recent studies have demonstrated the efficacy of zero-valent iron nanoparticles for the transformation of halogenated organic contaminants and heavy metals. In this work, we present a systematic characterization of the iron nanoparticles prepared with the method of ferric iron reduction by sodium borohydride. Particle size, size distribution and surface composition were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), high-resolution X-ray photoelectron spectroscopy (HR-XPS), X-ray absorption near edge structure (XANES) and acoustic/electroacoustic spectrometry. BET surface area, zeta (zeta) potential, iso-electric point (IEP), solution Eh and pH were also measured. Methods and results presented may foster better understanding, facilitate information exchange, and contribute to further research and development of iron nanoparticles for environmental and other applications.
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Wang HP, Long XH, Sun ZZ, Rigaud O, Xu QZ, Huang YC, Sui JL, Bai B, Zhou PK. Identification of differentially transcribed genes in human lymphoblastoid cells irradiated with 0.5 Gy of gamma-ray and the involvement of low dose radiation inducible CHD6 gene in cell proliferation and radiosensitivity. Int J Radiat Biol 2006; 82:181-90. [PMID: 16638715 DOI: 10.1080/09553000600632261] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To identify candidate genes specifically involved in response to low-dose irradiation in human lymphoblastoid cells; to better clarify the role of the human chromodomain helicase DNA binding protein 6 gene (CHD6), one of these genes, in cell proliferation and radiosensitivity. MATERIALS AND METHODS DNA microarray technology was used to analyse global transcriptional profile in human lymphoblastoid AHH-1 cells at 4 h after exposure to 0.5 Gy of gamma-ray. Gene expression changes were confirmed by semi-quantitative reverse transcription--polymerase chain reaction (RT-PCR) and Northern blot. RNA interfering technology was employed to knock-down the CHD6 gene in A549 cells. Colony-forming ability was used to analyse radiosensitivity. RESULTS The microarray assay revealed a set of 0.5 Gy-responsive genes, including 30 up-regulated genes and 45 down-regulated genes. The up-regulated genes include a number of genes involved in: signal transduction pathways, e.g., STAT3, CAMKK2, SIRT1, CREM, MAPK3K7IP2 and GPR56; transcription or DNA-binding, e.g., CHD6, CRSP3, SNURF, SH2 domain binding protein 1 and MIZF. Some of the down-regulated genes are involved in: cytoskeleton and cell movement (WASF2, LCP1, MSN, NIPSNAP1, KIF2C); DNA replication and repair (MCM2, MCM3, MCM7 and XRCC-4). Radiation-increased expression of CHD6 was also found in A549 cells and HeLa cells. The sustained CHD6 induction was restricted to relatively low doses (0.2 Gy or 0.5 Gy), no change occurring after 4 Gy irradiation. Silencing of CHD6 mediated by siRNA increased the growth rate of A549 cells by 40 approximately 60%. Most importantly, silencing CHD6 led to an increased radioresistance of A459 cells to radiation doses up to 2 Gy, but barely affected the sensitivity of cells at 4 and 8 Gy. CONCLUSION This study has identified a set of genes responsive to 0.5 Gy of gamma-rays. CDH6 gene can be specifically up-regulated by low dose irradiation, and its inducible expression could be involved in a low dose hypersensitive response.
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141
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Wang HP, Huang CC, Chen CH, Lin HY. Weber–Christian disease presenting with intractable fever and periorbital swelling mimicking angioedema. Clin Rheumatol 2006; 26:1002-4. [PMID: 16550303 DOI: 10.1007/s10067-006-0235-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Revised: 01/24/2006] [Accepted: 01/24/2006] [Indexed: 11/29/2022]
Abstract
A 22-year-old male patient with Weber-Christian disease (WCD) presenting with periorbital swelling is a very rare occurrence. Lobular panniculitis in the periorbital and anterior tibial skin was diagnosed in this patient, based on the histological findings from biopsy specimens. The differential diagnosis was done before administering systemic corticosteroid. A dramatic response was achieved several days later, but relapse with intractable fever occurred 1 month later. The use of other immunosuppressive agents failed, and he died of septic shock 2 months later. The preceding infection may have been the immunopathologic factor in the development of WCD. Other effective treatments for WCD may be described in the future.
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Wang HP, Hwang TL, Lee O, Tseng YJ, Shu CY, Lee SJ. Selective cytotoxicity of azatyrosinamides against ras-transformed NIH 3T3 cells. Bioorg Med Chem Lett 2005; 15:4272-4. [PMID: 16039850 DOI: 10.1016/j.bmcl.2005.06.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Revised: 06/21/2005] [Accepted: 06/21/2005] [Indexed: 11/30/2022]
Abstract
This study aims to develop novel azatyrosinamide compounds structurally modified from ras-specific antioncogenic azatyrosine. Analogues 4-15 were prepared and their inhibition on the growth of wild-type and ras-transformed NIH 3T3 cell lines was compared. Compound 12 was found to be the most active with IC50 16.5+/-2.2 microM which is 458-fold more potent than that of azatyrosine. The selective toxicity, defined as IC(50 wild-type)/IC(50 ras-transformed) for this compound was 138.5.
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Chen HA, Lin KC, Chen CH, Liao HT, Wang HP, Chang HN, Tsai CY, Chou CT. The effect of etanercept on anti-cyclic citrullinated peptide antibodies and rheumatoid factor in patients with rheumatoid arthritis. Ann Rheum Dis 2005; 65:35-9. [PMID: 15975966 PMCID: PMC1797988 DOI: 10.1136/ard.2005.038851] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To evaluate the changes in anti-cyclic citrullinated peptide antibodies (anti-CCP) and rheumatoid factor (RF) following etanercept treatment in patients with rheumatoid arthritis. METHODS The study included 90 patients with rheumatoid arthritis who failed treatment with disease modifying antirheumatic drugs (DMARDs). All patients were allowed to continue treatment with DMARDs; 52 of them received etanercept as a twice weekly 25 mg subcutaneous injection for three months, and the others did not. Serum samples were collected at baseline and one month intervals during the treatment course. The serum levels of anti-CCP and RF were tested by enzyme linked immunosorbent assay and nephelometry, respectively. RESULTS At baseline, 45 of the 52 etanercept treated patients (86.5%) and 32 of the 38 controls (84.2%) were positive for anti-CCP. Tests for RF were positive in 78.9% and 84.2% of patients with or without etanercept treatment, respectively. The serum levels of anti-CCP and RF decreased significantly after a three month etanercept treatment (p = 0.007 and p = 0.006, respectively). The average decrease from baseline calculated for each individual patient in the etanercept treated group was 31.3% for anti-CCP and 36% for RF. The variation in anti-CCP was positively correlated with the variation in disease activity, swollen and tender joint counts, RF, and C reactive protein. CONCLUSIONS Etanercept combined with DMARDs leads to a much greater decrease than DMARDs alone in the serum levels of anti-CCP and RF in rheumatoid arthritis, compatible with a reduction in clinical disease activity.
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Liu SH, Wang HP. In situ speciation studies of copper in the electroplating sludge under an electric field. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2004; 60:2387-2391. [PMID: 15249030 DOI: 10.1016/j.saa.2003.12.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Accepted: 12/09/2003] [Indexed: 05/24/2023]
Abstract
Speciation of copper in the electrokinetic treatments of an industrial sludge was studied by in situ extended X-ray absorption fine structural (EXAFS) and X-ray absorption near-edge structural (XANES) spectroscopies in the present work. The least-square fits (LSF) of the XANES spectra indicated that the main copper species in the sludge were Cu(NO)(3) (82%) and adsorbed copper (Cu/SiO(2)) (17%). Copper in the sludge possessed a Cu-O bond distance of 1.97A with a coordination number (CN) of 3.8. In the second shells, the bond distance of Cu-(O)-Si was 3.03A with a CN of 1.5. Most of Cu/SiO(2) was dissolved in the aqueous phase since little Cu-(O)-Si species in the sludge was found after 180 min of the electrokinetic treatments. About 69% of total Cu(II) was dissolved into the aqueous phase and 51% of which was migrated to the cathode under the electric field (5V cm(-1)) for 180 min.
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Liu SH, Wang HP. In situ speciation studies of copper-humic substances in a contaminated soil during electrokinetic remediation. JOURNAL OF ENVIRONMENTAL QUALITY 2004; 33:1280-7. [PMID: 15254109 DOI: 10.2134/jeq2004.1280] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Speciation of copper-humic substances (HS) in the electrokinetic remediation (EKR) of a contaminated soil was studied by in situ extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectroscopies. The least-square fits of the XANES spectra suggested that the main Cu species in the contaminated soil were Cu-HS (50%), CuCO(3) (28%), Cu(2)O (11%), and CuO (11%). The Cu-HS in the contaminated soil possessed equatorial and axial Cu-O bond distances of 1.94 and 2.17 A with coordination numbers (CNs) of 3.6 and 1.4, respectively. In the EKR process, the axial Cu-O bond distance in the Cu-HS complexes was increased by 0.15 A, which might be due to a ligand exchange of the Cu-HS with H(2)O molecules in the electrolyte. After 180 min of EKR, about 50% of the Cu-HS complexes (or 24% of total Cu) in the soil were dissolved and formed [Cu(H(2)O)(6)](2+) in the electrolyte, 71% (or 17% of total Cu in the soil) of which were migrated to the cathode under the electric field (5 V/cm). This work exemplifies the use of in situ EXAFS and XANES spectroscopies for speciation studies of Cu chelated with HS in the contaminated soil during EKR.
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Ku CC, Wang HP, Lee PH, Hsiao MC, Huang HL, Wang HC. Speciation of chromium in an electroplating sludge during thermal stabilization. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2003; 71:860-865. [PMID: 14672143 DOI: 10.1007/s00128-003-0215-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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148
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Wang HC, Wang HP, Peng CY, Liu HL, Huang HL. X-ray absorption spectroscopic studies of As-humic substances in the ground water of the Taiwan blackfoot disease area. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2003; 71:798-803. [PMID: 14672134 DOI: 10.1007/s00128-003-0204-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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149
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Hsiao MC, Wang HP. Speciation of copper in a contaminated soil. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2003; 71:804-809. [PMID: 14672135 DOI: 10.1007/s00128-003-0205-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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150
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Xu XH, Shi Y, Liu SH, Wang HP, Chang SG, Fisher JW, Pisharody S, Moran M, Wignarajah K. Method for the control of NOx emissions in long-range space travel. ENERGY & FUELS : AN AMERICAN CHEMICAL SOCIETY JOURNAL 2003; 17:1303-1310. [PMID: 14672086 DOI: 10.1021/ef0300803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The wheat straw, an inedible biomass that can be continuously produced in a space vehicle has been used to produce activated carbon for effective control of NOx emissions from the incineration of wastes. The optimal carbonization temperature of wheat straw was found to be around 600 degrees C when a burnoff of 67% was observed. The BET surface area of the activated carbon produced from the wheat straw reached as high as 300 m2/g. The presence of oxygen in flue gas is essential for effective adsorption of NO by activated carbon. On the contrary, water vapor inhibits the adsorption efficiency of NO. Consequently, water vapor in flue gas should be removed by drying agents before adsorption to ensure high NO adsorption efficiency. All of the NO in the flue gas was removed for more than 2 h by the activated carbons when 10% oxygen was present and the ratio of carbon weight to the flue gas flow rate (W/F) was 30 g min/L, with a contact time of 10.2 s. All of NO was reduced to N2 by the activated carbon at 450 degrees C with a W/F ratio of 15 g min/L and a contact time of 5.1 s. Reduction of the adsorbed NO also regenerated the activated carbon, and the regenerated activated carbon exhibited an improved NO adsorption efficiency. However, the reduction of the adsorbed NO resulted in a loss of carbon which was determined to be about 0.99% of the activated carbon per cycle of regeneration. The sufficiency of the amount of wheat straw in providing the activated carbon based on a six-person crew, such as the mission planned for Mars, has been determined. This novel approach for the control of NOx emissions is sustainable in a closed system such as the case in space travel. It is simple to operate and is functional under microgravity environment.
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