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Zhu M, Cummings P, Chu H, Xiang H. Urban and rural variation in walking patterns and pedestrian crashes. Inj Prev 2009; 14:377-80. [PMID: 19074243 DOI: 10.1136/ip.2007.018234] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To examine the urban and rural variation in walking patterns and pedestrian crashes. DESIGN The rates of pedestrians being struck by motor vehicles was estimated according to miles walked and resident years. SETTING New York State, USA during 2001 through 2002. PARTICIPANTS 35 732 pedestrians struck by vehicles. MAIN OUTCOME MEASURES The adjusted rate ratio (aRR) of pedestrian-vehicle crash and pedestrian injury based on resident years and miles walked according to urban and rural areas. RESULTS Compared with rural areas, the aRR for a pedestrian-vehicle collision, based on resident years, was 2.0 (95% CI 1.7 to 2.3) in small urban areas, 1.8 (95% CI 1.5 to 2.3) in mid-size urban areas, and 4.2 (95% CI 3.6 to 4.8) in the large urban area. The aRR based on miles walked was 2.3 (95% CI 1.6 to 3.2) in small urban areas, 2.0 (95% CI 1.4 to 2.9) in mid-size urban areas, and 1.9 (95% CI 1.4 to 2.7) in the large area. The aRR for a fatal pedestrian injury, based on miles walked, was 2.1 (95% CI 1.3 to 3.6) in small urban areas, 1.9 (95% CI 1.3 to 2.9) in mid-size urban areas, and 0.9 (95% CI 0.6 to 1.3) in the large urban area. CONCLUSIONS The rate of pedestrian crashes and injuries in small and mid-size urban areas was twice that in rural areas, whether based on resident years or miles walked. The high rate of pedestrian crashes in the large urban area based on resident years could be partly explained by the fact that residents in such areas walk about twice as much as residents in rural areas. The rate of fatal pedestrian injury based on miles walked was similar in the large urban area and rural areas.
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Raffatellu M, George MD, Akiyama Y, Hornsby MJ, Nuccio SP, Paixao TA, Butler BP, Chu H, Santos RL, Berger T, Mak TW, Tsolis RM, Bevins CL, Solnick JV, Dandekar S, Bäumler AJ. Lipocalin-2 resistance confers an advantage to Salmonella enterica serotype Typhimurium for growth and survival in the inflamed intestine. Cell Host Microbe 2009; 5:476-86. [PMID: 19454351 PMCID: PMC2768556 DOI: 10.1016/j.chom.2009.03.011] [Citation(s) in RCA: 397] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 02/24/2009] [Accepted: 03/24/2009] [Indexed: 12/12/2022]
Abstract
In response to enteric pathogens, the inflamed intestine produces antimicrobial proteins, a process mediated by the cytokines IL-17 and IL-22. Salmonella enterica serotype Typhimurium thrives in the inflamed intestinal environment, suggesting that the pathogen is resistant to antimicrobials it encounters in the intestinal lumen. However, the identity of these antimicrobials and corresponding bacterial resistance mechanisms remain unknown. Here, we report that enteric infection of rhesus macaques and mice with S. Typhimurium resulted in marked Il-17- and IL-22-dependent intestinal epithelial induction and luminal accumulation of lipocalin-2, an antimicrobial protein that prevents bacterial iron acquisition. Resistance to lipocalin-2, mediated by the iroBCDE iroN locus, conferred a competitive advantage to the bacterium in colonizing the inflamed intestine of wild-type but not of lipocalin-2-deficient mice. Thus, resistance to lipocalin-2 defines a specific adaptation of S. Typhimurium for growth in the inflamed intestine.
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Mukherjee S, Partch CL, Lehotzky RE, Whitham CV, Chu H, Bevins CL, Gardner KH, Hooper LV. Regulation of C-type lectin antimicrobial activity by a flexible N-terminal prosegment. J Biol Chem 2008; 284:4881-8. [PMID: 19095652 PMCID: PMC2643518 DOI: 10.1074/jbc.m808077200] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Members of the RegIII family of intestinal C-type lectins are directly antibacterial proteins that play a vital role in maintaining host-bacterial homeostasis in the mammalian gut, yet little is known about the mechanisms that regulate their biological activity. Here we show that the antibacterial activities of mouse RegIIIgamma and its human ortholog, HIP/PAP, are tightly controlled by an inhibitory N-terminal prosegment that is removed by trypsin in vivo. NMR spectroscopy revealed a high degree of conformational flexibility in the HIP/PAP inhibitory prosegment, and mutation of either acidic prosegment residues or basic core protein residues disrupted prosegment inhibitory activity. NMR analyses of pro-HIP/PAP variants revealed distinctive colinear backbone amide chemical shift changes that correlated with antibacterial activity, suggesting that prosegment-HIP/PAP interactions are linked to a two-state conformational switch between biologically active and inactive protein states. These findings reveal a novel regulatory mechanism governing C-type lectin biological function and yield new insight into the control of intestinal innate immunity.
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Tang JC, Taniguchi H, Chu H, Zhou Q, Nagata S. Isolation and characterization of alginate-degrading bacteria for disposal of seaweed wastes. Lett Appl Microbiol 2008; 48:38-43. [PMID: 19018967 DOI: 10.1111/j.1472-765x.2008.02481.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Isolation of novel alginate degrading bacteria for the disposal of seaweed waste in composting process. METHODS AND RESULTS Decomposition of alginate polymers was checked by the 3,5-dinitrosalicylic acid (DNS) method for reducing sugar, and absorbance at 235 nm for unsaturated sugar. A bacterium A7 was isolated from wakame compost and confirmed to belong to the genus Gracilibacillus by partial 16S rDNA analysis. The optimum condition for the growth of A7 in a medium containing 5 g l(-1) of sodium alginate is as follows: pH, 8.5-9.5; NaCl, 0.5 mol l(-1); temperature, 30 degrees C and polypeptone as nutrient content, 2-5 g l(-1). In a laboratory-scale composting experiment, the alginate content in wakame compost decreased to 14.3% after 72 h of composting from an initial value of 36%, indicating the effectiveness of alginate decomposition of A7 in wakame composting. CONCLUSIONS The bacterium A7 was found to be alginate lyase-producing in genus Gracilibacillus and effective in degrading alginate to oligosaccharides in wakame during composting process. SIGNIFICANCE AND IMPACT OF THE STUDY Development of new methods for the disposal of marine wastes and production of functional products.
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105
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Karlsson J, Pütsep K, Chu H, Kays RJ, Bevins CL, Andersson M. Regional variations in Paneth cell antimicrobial peptide expression along the mouse intestinal tract. BMC Immunol 2008; 9:37. [PMID: 18637162 PMCID: PMC2488317 DOI: 10.1186/1471-2172-9-37] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Accepted: 07/17/2008] [Indexed: 12/15/2022] Open
Abstract
Background Enteric antimicrobial peptides secreted from Paneth cells, including α-defensins (in mice named cryptdins), are key effector molecules of innate immunity in the small intestine. The importance of Paneth cells α-defensins emerged from studies of enteric bacterial infection in genetically modified mice, as well as from recent studies linking reduced levels of these α-defensins to Crohn's disease localized to the ileum. However, analysis of expression of Paneth cell α-defensins is incomplete. We therefore performed a comprehensive evaluation of the distribution of antimicrobial molecules along the mouse small intestinal tract to identify potential variations in regional expression. Results In conventionally reared mice, the repertoire of Paneth cell antimicrobials differs between duodenum and ileum. In contrast to the uniform expression of most Paneth cell antimicrobials, both cryptdin 4 and cryptdin-related sequences (CRS) 4C peptides were expressed at progressively increasing amounts (101- and 104-fold, respectively) comparing duodenum and ileum. In tissues other than the small intestine, expression of CRS peptides was noted in thymus and caecum. Most Paneth cell products were also produced in the small intestine of germ-free mice at levels similar to those in controls, however CRS4C and RegIIIγ had reduced levels in the former (3- and 8-fold, respectively). No significant changes in expression levels of Paneth cell antimicrobial peptides was observed after oral challenge with either Salmonella enterica serovar typhimurium or Listeria monocytogenes, supporting current notions on the constitutive nature of this defensive system. Conclusion The repertoire of antimicrobial peptides changes along the small intestinal tract, and a subset of these molecules are up-regulated upon colonization, but not in response to enteric bacterial pathogens. The changes detected upon colonization suggest that Paneth cell antimicrobial peptides may play an important role in commensal microbial homeostasis, in addition to their proposed role in protection against infection. In addition, the differential expression of CRS4C along the small intestine suggests mechanisms of regulation that are distinct from other Paneth cell derived antimicrobial peptides.
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Puvvada SD, O’Neil BH, Deal A, Greene K, Chu H, Baldwin AS, Funkhouser WK. Prognostic implication of NF-κB and BCL3 activation in metastatic colorectal cancer. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.11090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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107
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Koshiol J, Poole C, Chu H, Pimenta JM, Lindsay L, Jenkins D, Smith JS. The Authors Respond to "HPV Persistence and Cervical Cancer Screening". Am J Epidemiol 2008. [DOI: 10.1093/aje/kwn129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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108
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Riddler SA, Li X, Chu H, Kingsley LA, Dobs A, Evans R, Palella F, Visscher B, Chmiel JS, Sharrett A. Longitudinal changes in serum lipids among HIV-infected men on highly active antiretroviral therapy. HIV Med 2007; 8:280-7. [PMID: 17561873 DOI: 10.1111/j.1468-1293.2007.00470.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The aim of the study was to describe longitudinal changes in serum lipids among HIV-infected men receiving highly active antiretroviral therapy (HAART) with long-term follow-up. METHODS A total of 304 HIV-infected men who initiated HAART and who had serum lipid measurements prior to and for up to 7 years after HAART initiation were identified from the Multicenter AIDS Cohort Study (MACS). Mean levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were examined at biannual time-points. RESULTS Significant lipid changes were seen within 0.5 years of HAART initiation but increases in TC (+1.09 mmol/L), LDL-C (+0.57 mmol/L), HDL-C (+0.16 mmol/L) and non-HDL-C (+0.91 mmol/L) reached peak levels 2-3 years after HAART initiation. Declines in serum TC, LDL-C and non-HDL-C in subsequent years occurred concurrently with a substantial increase in use of lipid-lowering medications (from 1% usage pre-HAART to 43% 6-7 years after HAART initiation) but the proportion of men who either were treated with cholesterol-lowering medication or had elevated cholesterol levels (>5.18 mmol/L) did not change during the 2-7-year interval after HAART. Mean HDL-C also decreased after 2-3 years and was low (<1.04 mmol/L) in 55% of HIV-infected men 6-7 years after HAART initiation. CONCLUSIONS Atherogenic serum lipids increased early after the initiation of HAART, peaked at 2-3 years and remained high or required treatment thereafter. Low HDL-C levels persisted in the majority of men. The long-term effects of lipid abnormalities on cardiovascular risk and the effectiveness and toxicity of prolonged use of lipid-lowering medications in combination with HAART are not known.
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Raffatellu M, Santos RL, Chessa D, Wilson RP, Winter SE, Rossetti CA, Lawhon SD, Chu H, Lau T, Bevins CL, Adams LG, Bäumler AJ. The capsule encoding the viaB locus reduces interleukin-17 expression and mucosal innate responses in the bovine intestinal mucosa during infection with Salmonella enterica serotype Typhi. Infect Immun 2007; 75:4342-50. [PMID: 17591794 PMCID: PMC1951168 DOI: 10.1128/iai.01571-06] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The viaB locus contains genes for the biosynthesis and export of the Vi capsular antigen of Salmonella enterica serotype Typhi. Wild-type serotype Typhi induces less CXC chemokine production in tissue culture models than does an isogenic viaB mutant. Here we investigated the in vivo relevance of these observations by determining whether the presence of the viaB region prevents inflammation in two animal models of gastroenteritis. Unlike S. enterica serotype Typhimurium, serotype Typhi or a serotype Typhi viaB mutant did not elicit marked inflammatory changes in the streptomycin-pretreated mouse model. In contrast, infection of bovine ligated ileal loops with a serotype Typhi viaB mutant resulted in more fluid accumulation and higher expression of the chemokine growth-related oncogene alpha (GROalpha) and interleukin-17 (IL-17) than did infection with the serotype Typhi wild type. There was a marked upregulation of IL-17 expression in both the bovine ligated ileal loop model and the streptomycin-pretreated mouse model, suggesting that this cytokine is an important component of the inflammatory response to infection with Salmonella serotypes. Introduction of the cloned viaB region into serotype Typhimurium resulted in a significant reduction of GROalpha and IL-17 expression and in reduced fluid secretion. Our data support the idea that the viaB region plays a role in reducing intestinal inflammation in vivo.
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MESH Headings
- Animals
- Antigens, Bacterial/genetics
- Antigens, Bacterial/physiology
- Bacterial Capsules/biosynthesis
- Bacterial Capsules/genetics
- Bacterial Capsules/immunology
- Cattle
- Cell Movement/genetics
- Cell Movement/immunology
- Disease Models, Animal
- Down-Regulation/genetics
- Down-Regulation/immunology
- Genetic Markers
- Immunity, Mucosal/genetics
- Inflammation Mediators/metabolism
- Inflammation Mediators/physiology
- Interleukin-17/antagonists & inhibitors
- Interleukin-17/biosynthesis
- Interleukin-17/genetics
- Intestinal Mucosa/immunology
- Intestinal Mucosa/microbiology
- Intestinal Mucosa/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Neutrophils/immunology
- Neutrophils/microbiology
- Neutrophils/pathology
- Operon/genetics
- Polysaccharides, Bacterial/genetics
- Polysaccharides, Bacterial/physiology
- Salmonella Infections, Animal/immunology
- Salmonella Infections, Animal/pathology
- Salmonella Infections, Animal/prevention & control
- Salmonella typhi/genetics
- Salmonella typhi/immunology
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Cairns C, Adler K, Moss T, Crews A, Chu H, Kraft M. Mycoplasma Pneumoniae Increases Airway Mucin Production in Asthmatics. Acad Emerg Med 2007. [DOI: 10.1197/j.aem.2007.03.1258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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111
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Hsueh HT, Chu H, Yu ST. A batch study on the bio-fixation of carbon dioxide in the absorbed solution from a chemical wet scrubber by hot spring and marine algae. CHEMOSPHERE 2007; 66:878-86. [PMID: 16860839 DOI: 10.1016/j.chemosphere.2006.06.022] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2005] [Revised: 06/12/2006] [Accepted: 06/13/2006] [Indexed: 05/11/2023]
Abstract
Carbon dioxide mass transfer is a key factor in cultivating micro-algae except for the light limitation of photosynthesis. It is a novel idea to enhance mass transfer with the cyclic procedure of absorbing CO(2) with a high performance alkaline abosorber such as a packed tower and regenerating the alkaline solution with algal photosynthesis. Hence, the algae with high affinity for alkaline condition must be purified. In this study, a hot spring alga (HSA) was purified from an alkaline hot spring (pH 9.3, 62 degrees C) in Taiwan and grows well over pH 11.5 and 50 degrees C. For performance of HSA, CO(2) removal efficiencies in the packed tower increase about 5-fold in a suitable growth condition compared to that without adding any potassium hydroxide. But ammonia solution was not a good choice for this system with regard to carbon dioxide removal efficiency because of its toxicity on HSA. In addition, HSA also exhibits a high growth rate under the controlled pHs from 7 to 11. Besides, a well mass balance of carbon and nitrogen made sure that less other byproducts formed in the procedure of carboxylation. For analysis of some metals in HSA, such as Mg, Mn, Fe, Zn, related to the photosynthesis increased by a rising cultivated pH and revealed that those metals might be accumulated under alkaline conditions but the growth rate was still limited by the ratio of bicarbonate (useful carbon source) and carbonate. Meanwhile, Nannochlopsis oculta (NAO) was also tested under different additional carbon sources. The results revealed that solutions of sodium/potassium carbonate are better carbon sources than ammonia carbonate/bicarbonate for the growth of NAO. However, pH 9.6 of growth limitation based on sodium was lower than one of HSA. The integrated system is, therefore, more feasible to treat CO(2) in the flue gases using the algae with higher alkaline affinity such as HSA in small volume bioreactors.
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112
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Wehkamp J, Chu H, Shen B, Feathers RW, Kays RJ, Lee SK, Bevins CL. Paneth cell antimicrobial peptides: Topographical distribution and quantification in human gastrointestinal tissues. FEBS Lett 2006; 580:5344-50. [PMID: 16989824 DOI: 10.1016/j.febslet.2006.08.083] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 08/23/2006] [Accepted: 08/28/2006] [Indexed: 12/20/2022]
Abstract
Antimicrobial peptides and proteins are key effectors of innate immunity, expressed both by circulating phagocytic cells and by epithelial cells of mucosal tissues. In the human small intestine, Paneth cells are secretory epithelial cells that express the antimicrobials human alpha-defensin-5 (HD5), HD6, lysozyme and secretory phospholipase A(2) (sPLA(2)), and recent studies have implicated reduced HD5 and HD6 expression levels in the pathogenesis of ileal Crohn's disease. However, expression levels of these molecules have not been determined routinely by techniques that readily permit quantitative comparisons of their distribution between tissues and samples. Using quantitative real-time PCR with external standards and Northern blot analysis, we compared expression levels of mRNA encoding these four Paneth cell antimicrobial peptides, as well as circulating human neutrophil defensins in several different gastrointestinal tissues and the bone marrow. HD5 and HD6 were the most abundant antimicrobials expressed in the small intestine. The concentration of HD5 mRNA is approximately 5 x 10(5) copies per 10ng RNA in the jejunum and ileum; HD6 mRNA levels were about six times lower than those of HD5. With the exception of low levels in the pancreas (10(3) copies/10 ng RNA), the expression of HD5 and HD6 in tissues other than small intestine was at or below detectable limits. The expression of sPLA2 and lysozyme mRNA was observed in the small intestine (approximately, 3 x 10(3) and 9 x 10(3) copies/10 ng RNA, respectively), but also in several other tissues. Lysozyme expression was high in the duodenum (10(5) copies/10 ng RNA), and the protein localized to both Brunner's glands in the lamina propria and Paneth cells. By comparison, the hematopoietic alpha-defensins HNP1-3 mRNA were detected at 6 x 10(5) copies per 10 ng RNA in the bone marrow. These quantitative RT-PCR data from healthy tissues represents the first quantitative topographical assessment of antimicrobial expression in the gastrointestinal tract and provides a means to directly compare expression levels between healthy tissues and disease specimens for multiple antimicrobial peptides.
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113
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Chu H, Cole S. Use of a Generalized Versus a General Linear Mixed Model for Bivariate Meta-Analysis of Sensitivity and Specificity with Sparse Data. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s73-d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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114
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Chu H, Cole SR. Estimating Biomarker-Based HIV Incidence Using Prevalence Data in High Risk Groups with Missing Outcome. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s228-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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115
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Cole S, Chu H, Brookmeyer R. Confidence Intervals for Biomarker-Based Hiv Incidence Estimates using Prevalent Data. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s74-d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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116
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Chu H, Gange SJ, Li X, Hoover DR, Chmiel JS, Shankarappa R, Jacobson LP. HIV Viral Load Trajectory among Treatment Naive Men and Women Initiating Long-Term Haart: An Application Using a Segmental Bernoulli/Lognormal Random Effects Model with Left Censoring. Am J Epidemiol 2006. [DOI: 10.1093/aje/163.suppl_11.s228-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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117
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Kuo T, Fan K, Kuochen H, Han Y, Chu H, Lee Y. Anomalous decrease in groundwater radon before the Taiwan M6.8 Chengkung earthquake. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2006; 88:101-6. [PMID: 16533545 DOI: 10.1016/j.jenvrad.2006.01.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2005] [Revised: 12/26/2005] [Accepted: 01/20/2006] [Indexed: 05/07/2023]
Abstract
On December 10, 2003, an earthquake of magnitude (M) 6.8, the strongest since 1951, occurred near the Chengkung area in eastern Taiwan. Approximately 65 d prior to the 2003 Chengkung earthquake, precursory changes in the groundwater radon concentration were observed at the Antung radon-monitoring station located 20 km from the epicenter. The radon anomaly was a decrease from a background level of 28.9 BqL(-1) to a minimum of 12.2 BqL(-1). Observations at the Antung hot spring suggest that the groundwater radon, when observed under suitable geological conditions, can be a sensitive tracer for strain changes in the crust preceding an earthquake.
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Wehkamp J, Salzman NH, Porter E, Nuding S, Weichenthal M, Petras RE, Shen B, Schaeffeler E, Schwab M, Linzmeier R, Feathers RW, Chu H, Lima H, Fellermann K, Ganz T, Stange EF, Bevins CL. Reduced Paneth cell alpha-defensins in ileal Crohn's disease. Proc Natl Acad Sci U S A 2005; 102:18129-34. [PMID: 16330776 PMCID: PMC1306791 DOI: 10.1073/pnas.0505256102] [Citation(s) in RCA: 706] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Accepted: 10/24/2005] [Indexed: 02/06/2023] Open
Abstract
The pathogenesis of Crohn's disease (CD), an idiopathic inflammatory bowel disease, is attributed, in part, to intestinal bacteria that may initiate and perpetuate mucosal inflammation in genetically susceptible individuals. Paneth cells (PC) are the major source of antimicrobial peptides in the small intestine, including human alpha-defensins HD5 and HD6. We tested the hypothesis that reduced expression of PC alpha-defensins compromises mucosal host defenses and predisposes patients to CD of the ileum. We report that patients with CD of the ileum have reduced antibacterial activity in their intestinal mucosal extracts. These specimens also showed decreased expression of PC alpha-defensins, whereas the expression of eight other PC products either remained unchanged or increased when compared with controls. The specific decrease of alpha-defensins was independent of the degree of inflammation in the specimens and was not observed in either CD of the colon, ulcerative colitis, or pouchitis. The functional consequence of alpha-defensin expression levels was examined by using a transgenic mouse model, where we found changes in HD5 expression levels, comparable to those observed in CD, had a pronounced impact on the luminal microbiota. Thus, the specific deficiency of PC defensins that characterizes ileal CD may compromise innate immune defenses of the ileal mucosa and initiate and/or perpetuate this disease.
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119
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Ko TH, Chu H. Characterization of southern Taiwan red soils as a regenerable sorbent for sorption of hydrogen sulfide from coal gas with spectroscopic techniques. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:407-14. [PMID: 16257742 DOI: 10.1016/j.saa.2005.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 01/20/2005] [Indexed: 05/05/2023]
Abstract
The purpose of this research is to use red soils as a high-temperature regenerable sorbent for sorption of hydrogen sulfide from coal gas and collocates with a series of spectroscopic apparatuses in order to investigate the structure changes after multiple sorption/regeneration processes. Results indicate that red soils could be reused after 10 multiple sorption/regeneration cycles and maintain approximately 80% sorption efficiency. With EDS and EA analyses, residual sulfur species are detected in the 10th regenerated red soils and exist with values of 0.6 and 0.33%, respectively. Undesired sulfur species including sulfide, sulfate and elemental sulfur are further identified by XPS spectroscopy. With the best regression fitting results, sulfate species is the dominative sulfur species, which occupies approximately 71% of residual sulfur. It is believed that these residual sulfur species are the major cause to result in red soils' deterioration after regeneration and reduce the sorption efficiency. Appreciable amounts of regeneration gases CO, CO(2) and SO(2) are detected by on-line FTIR spectroscopy. Their formation mechanisms are attributed to the different gas-solid reaction, one is the reaction of carbon and oxygen, and the other is FeS and oxygen. From the analysis of solid-state nuclear magnetic resonance spectroscopy (SSNMR), a significant change for (27)Al and (29)Si and it is established that a portion of aluminum is reformed into pentacoordinated structure. Formation of aluminosilicate is maybe another reason to result in deterioration as a result of the loss of surface area.
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120
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Ko TH, Chu H. Spectroscopic study on sorption of hydrogen sulfide by means of red soil. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 61:2253-9. [PMID: 15911419 DOI: 10.1016/j.saa.2004.09.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2004] [Accepted: 09/01/2004] [Indexed: 05/02/2023]
Abstract
This paper reports the results of the characterization of red soils in relation to the sorption of H2S from coal gas at 500 degrees C by spectroscopic techniques in order to provide more information on red soils' structural change both before and after reaction. In addition, by-products analysis has also been studied using Fourier transform infrared (FTIR) spectroscopy. Before and after the experiments the red soils were characterized with X-ray powder diffraction (XRPD), energy dispersion spectrum (EDS), X-ray photoelectron spectroscopy (XPS) and FTIR spectroscopy. XRPD results indicate that iron oxide species disappear from the original to reacted red soil. EDS analysis shows that a significant amount of sulfur is present in the reacted red soil, which is in agreement with the results of the elemental analysis and the calculated value based on breakthrough curve. XPS regression fitting results further indicate that sulfur retention may be associated with the iron oxides. S 2p XPS fittings point out that the major sulfur species present in the reacted red soil are composed of S(-2), elemental sulfur, polysulfide, sulfite and sulfate. Additionally, the binding energy of iron shifts to a lower position for the reacted red soil, which indicates that iron oxides in the original red soil have been converted into iron sulfide. Appreciable amounts of the by-products CO2, SO2 and COS are detected by on-line FTIR spectroscopy during the initial and later stages of the sorption process. The formation of CO2 is related to the water-shift reaction, and SO2 is probably attributable to the reaction of organic matters and H2S. The concentration of COS is quantified by GC/FPD and found it to be about 350 ppm, which is close to the equilibrium concentration of the reaction of inlet CO and H2S at a temperature of 500 degrees C.
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Chu H, Gange SJ, Yamashita TE, Hoover DR, Chmiel JS, Margolick JB, Jacobson LP. 259: CD4 T-Cell Trajectory Among HIV-Infected Men and Women on Long Term Highly Active Antiretroviral Therapy: An Application using a Bayesian Random Change Point Model. Am J Epidemiol 2005. [DOI: 10.1093/aje/161.supplement_1.s65b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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122
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Chu H, Wang Z, Cole SR. 394: Sensitivity Analysis of Misclassification: A Graphic and a Bayesian Method. Am J Epidemiol 2005. [DOI: 10.1093/aje/161.supplement_1.s99a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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123
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Cole SR, Chu H, Allison PD. 270: Analysis of Bidirectional Recurrence Times. Am J Epidemiol 2005. [DOI: 10.1093/aje/161.supplement_1.s68a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ko TH, Chu H, Chaung LK, Tseng TK. High temperature removal of hydrogen sulfide using an N-150 sorbent. JOURNAL OF HAZARDOUS MATERIALS 2004; 114:145-152. [PMID: 15511585 DOI: 10.1016/j.jhazmat.2004.08.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2004] [Revised: 07/15/2004] [Accepted: 08/15/2004] [Indexed: 05/24/2023]
Abstract
In this study, an N-150 sorbent was used as a high temperature desulfurization sorbent for the removal of hydrogen sulfide from coal gas in a fixed bed reactor. The results indicate that the N-150 sorbent could be used for H(2)S removal in the tested temperature ranges. Regeneration test also reveals that utilization of the N-150 sorbent maintains up to 85% compared to the fresh sorbent. No significant degeneration occurs on the N-150 sorbent. In addition, various concentrations of H(2)S, H(2) and CO were also considered in the performance test of the N-150 sorbent. Except for H(2)S, H(2) and CO act the important roles in the high temperature desulfurization. By increasing the H(2) concentration, the sulfur capacity of the sorbent decreases and an adverse result is observed in the case of increasing CO concentration. This can be explained via water-shift reaction. On the basis of the instrument analysis, X-ray powder diffraction determination and SEM images with EDS spectrum characterization, residual sulfur is found in the regenerated N-150 sorbent and this sulfur species is sulfate which resulted by incomplete regeneration. The sulfate formation and sintering effect are major reasons to cause activity loss in the sulfidation/regeneration cycles.
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Zhou X, Chu H, Chen Q, Li X. Voluntary Modulation of Early and Late Inhibition in Visual Orienting. J Vis 2004. [DOI: 10.1167/4.8.258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Weintraub WS, Mahoney EM, Zhang Z, Chu H, Hutton J, Buxton M, Booth J, Nugara F, Stables RH, Dooley P, Collinson J, Stuteville M, Delahunty N, Wright A, Flather MD, De Cock E. One year comparison of costs of coronary surgery versus percutaneous coronary intervention in the stent or surgery trial. Heart 2004; 90:782-8. [PMID: 15201249 PMCID: PMC1768324 DOI: 10.1136/hrt.2003.015057] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/04/2003] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES To compare initial and one year costs of coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) in the stent or surgery trial. DESIGN Prospective, unblinded, randomised trial. SETTING Multicentre study. PATIENTS 988 patients with multivessel disease. INTERVENTIONS CABG and stent assisted PCI. MAIN OUTCOME MEASURES Initial hospitalisation and one year follow up costs. RESULTS At one year mortality was 2.5% in the PCI arm and 0.8% in the CABG arm (p = 0.05). There was no difference in the composite of death or Q wave myocardial infarction (6.9% for PCI v 8.1% for CABG, p = 0.49). There were more repeat revascularisations with PCI (17.2% v 4.2% for CABG). There was no significant difference in utility between arms at six months or at one year. Quality adjusted life years were similar 0.6938 for PCI v 0.6954 for PCI, Delta = 0.00154, 95% confidence interval (CI) -0.0242 to 0.0273). Initial length of stay was longer with CABG (12.2 v 5.4 days with PCI, p < 0.0001) and initial hospitalisation costs were higher (7321 pounds sterling v 3884 pounds sterling for PCI, Delta = 3437 pounds sterling, 95% CI 3040 pounds sterling to 3848 pounds sterling). At one year the cost difference narrowed but costs remained higher for CABG (8905 pounds sterling v 6296 pounds sterling for PCI, Delta = 2609 pounds sterling, 95% CI 1769 pounds sterling to 3314 pounds sterling). CONCLUSIONS Over one year, CABG was more expensive and offered greater survival than PCI but little added benefit in terms of quality adjusted life years. The additional cost of CABG can be justified only if it offers continuing benefit at no further increase in cost relative to PCI over several years.
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Chien TW, Chu H, Hsu WC, Tseng TK, Hsu CH, Chen KY. A feasibility study on the predictive emission monitoring system applied to the Hsinta power plant of Taiwan Power Company. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2003; 53:1022-1028. [PMID: 12943322 DOI: 10.1080/10473289.2003.10466241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.
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Chu H, Hao GH, Tseng TK. Laboratory study of poisoning of a MnO/Fe2O3 catalyst by dimethyl sulfide and dimethyl disulfide. JOURNAL OF HAZARDOUS MATERIALS 2003; 100:301-316. [PMID: 12835030 DOI: 10.1016/s0304-3894(03)00135-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The catalytic incineration of dimethyl sulfide and dimethyl disulfide in a MnO/Fe(2)O(3) fixed bed catalytic reactor was studied. This paper provides information on the affect of the operating parameters that included: inlet temperature, space velocity, VOC concentration and O(2) concentration. The results show that the conversion of VOCs increases as the inlet temperature increases and the space velocity decreases. The higher the concentration of VOCs, the lower their conversions. The O(2) concentration has no affect on the conversion of VOCs. VOCs have poisoning affects on the MnO/Fe(2)O(3) catalyst, especially at lower temperatures.
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Chu H, Nieuwenhuijsen MJ. Distribution and determinants of trihalomethane concentrations in indoor swimming pools. Occup Environ Med 2002; 59:243-7. [PMID: 11934951 PMCID: PMC1740275 DOI: 10.1136/oem.59.4.243] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES For many decades chlorination has been used as a major disinfectant process for public drinking and swimming pool water in many countries. However, there has been rising concern over the possible link between disinfectant byproducts (DBPs) and adverse reproductive outcomes. The purpose of this study was to estimate the concentrations of trihalomethanes (THMs) in some indoor swimming pools in London and their variation within and between pools and any correlation with other factors. METHODS Water samples were collected from eight different indoor swimming pools in London. A total of 44 pool samples were collected and analysed for total organic content (TOC) and THMs. Water and air temperature were measured along with the pH during the collection of pool samples. The level of turbulence and the number of people in the pool at the time were also assessed. RESULTS The geometric mean concentration for all swimming pools of TOC was 5.8 mg/l, of total THMs (TTHMs) 132.4 microg/l, and for chloroform 113.3 microg/l. There was a clear positive linear correlation between the number of people in the swimming pool and concentrations of TTHMs and chloroform (r=0.7, p<0.01), and a good correlation between concentrations of TOC and TTHMs (r=0.5, p<0.05) and water temperature and concentrations of TTHMs (r=0.5, p<0.01). There was a larger variation in THMs within pools than between pools. CONCLUSION Relatively high concentrations of THMs were found in London's indoor swimming pools. The levels correlated with the number of people in the pool, water temperature, and TOC. The variation in concentrations of THMs was greater within pools than between pools.
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Guo X, Wang H, Chu H. [Human factor VIII expression in retrovirus vector-transduced bone marrow stromal cells]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2001; 22:461-3. [PMID: 11758224] [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 explore the feasibility of bone marrow stromal cells (BMSCs) used for gene therapy of hemophilia A. METHODS Murine and rabbit BMSCs were transduced with a recombinant replication-incompetent retrovirus LNC-FVIII delta B, which encloses a B-domain-deleted (760aa-1,639aa) human factor VIII cDNA. An optimized protocol involving temperature declining (32 degrees C) and centrifugation was used. Antigen and coagulant activity of human FVIII in the cell culture medium were measured by ELISA assay and one-stage method, respectively. Semi-quantitative PCR was performed for the transduction efficiencies. Western blot was used for FVIII protein analysis. RESULTS Transduction efficiencies were increased 5- to 8-fold by temperature decline and centrifugation, which resulted in high expression and secretion of FVIII in transduced mouse[(556 +/- 80) ng/10(6) cells/24 hr] and rabbit [480 +/- 56) ng/10(6) cells/24 hr] BMSCs. Coagulant activities of human FVIII secreted from transduced murine and rabbit BMSCs were 2.42 U/10(6) cells/24 hr and 1.8 U/10(6) cells/24 hr, respectively. Western blot analysis demonstrated that the B domain-deleted FVIII cDNA was secreted predominantly as heavy and light chain heterodimers that resemble the native forms in human plasma. CONCLUSIONS It was demonstrated that the BMSCs system has potential utility in the gene therapy for hemophilia A.
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Tseng TK, Chu H. The kinetics of catalytic incineration of styrene over a MnO/Fe2O3 catalyst. THE SCIENCE OF THE TOTAL ENVIRONMENT 2001; 275:83-93. [PMID: 11482406 DOI: 10.1016/s0048-9697(00)00856-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Catalytic incineration is one of the cost-effective technologies to deal with unwanted volatile organic compounds (VOCs). Catalytic incineration of styrene over a MnO/Fe2O3 catalyst was carried out in a bench scale catalytic incinerator. Three kinetic models, the power-rate law, the Mars and van Krevelen model and the Langmuir-Hinshelwood model were used to analyze the results. A differential reactor design was used for best fit of kinetic models in this study. The results show that the Langmuir-Hinshelwood model may be feasible to describe the catalytic incineration of styrene. This suggests that the chemical adsorption of either O2 molecules or O atoms is important in the process of catalytic incineration of styrene.
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Chu H, Chien TW, Li SY. Simultaneous absorption of SO2 and NO from flue gas with KMnO4/NaOH solutions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2001; 275:127-135. [PMID: 11482398 DOI: 10.1016/s0048-9697(00)00860-3] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The wet scrubbing combined SOx/NOx removal system is an advanced air pollution control device. This study attempts to understand the absorption kinetics in the system. The absorption of diluted SO2 and simultaneous absorption of diluted SO2 and NO, as occurs in flue gases, in a stirred tank reactor with KMnO4/NaOH solutions were carried out at 50 degrees C. The liquid-side and gas-side mass transfer coefficients of the system were determined. The results indicate that the absorption of SO2 is close to completely gas-film controlled where the NaOH concentration is greater than 0.1 M or the KMnO4 concentration is greater than 0.05 M. The increasing gas flow rate has a positive effect on the absorption rate of SO2. The existence of O2 has no significant effect on the absorption rate of SO2. Adding SO2 would decrease the absorption rate of NO; however, the addition of NO has no effect on the absorption rate of SO2.
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Zeng Q, Zhu J, Xie Z, Chu H, Cao Z. [Does response of rape to La and critical concentration of La in red earth]. HUAN JING KE XUE= HUANJING KEXUE 2001; 22:77-80. [PMID: 11569120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The effects of different concentration of La added in red soil on the growth, yield, content of chlorophyll and peroxidase(POD) activity of rape were studied by pot experiments. The results showed that the growth and yield of rape could be improved by low concentration of La3+, however there was no significant difference between the treatment and the control, and inhibited when the dose were more than 300 mg kg-1 and killed after 600 mg.kg-1 La was added. The decrease of chlorophyll content and chlorophyll a/b was observed when the exogenous concentration of La was more than 15 mg.kg-1. POD activity increased gradually with increasing concentration and prolonging reaction. The feasible application level of La was suggested to be below 15 mg.kg-1.
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Guo X, Wang H, Chu H, Wang X, Qu B, Li Z, Qi Z, Wang Z. High level expression of human factor VIII in mammalian cells after retroviral-mediated gene transfer. Chin Med J (Engl) 2001; 114:690-3. [PMID: 11780328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To develop a retroviral-mediated high efficient expression system of human coagulation factor VIII. METHODS The LNC-FVIIIBD retroviral vector was generated by cloning a human B-domain-deleted (760aa-1639aa) Factor VIII (FVIII) cDNA (FVIII cDNA BD) into the retroviral vector pLNCX. Several mammalian cell lines, including NIH3T3, CHO, Cos-7 and human hepatic cell line, L-02, were transduced with viral supernatant from the highest virus-producing PA317 clone. Antigen and coagulant activity of human FVIII in cell culture medium were measured by ELISA and a one-stage method, respectively. RT-PCR was performed for the detection of FVIIIBD mRNA. RESULTS Human FVIII was expressed in all four target cells, with the highest FVIII expression observed in NIH3T3. The coagulant activity of secreted FVIII was up to 1.6 U/10(6) cells.24 hrs-1, and the FVIII antigen was 500 ng/10(6) cells.24 hrs-1. FVIII coagulant activity and antigen expressed by transduced CHO cells were 0.12 U/10(6) cells.24 hrs-1 and 62.4 ng/10(6) cells.24 hrs-1, respectively. Human FVIII expression was relatively low in Cos-7 and L-02 cells. RT-PCR results demonstrated transcription of FVIII cDNA BD in the target cells. CONCLUSIONS The constructed retroviral vector was able to direct high level expression of human FVIII in various mammalian cell lines. It has potential utility in the future gene therapy for Hemophilia A.
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Chu H, Chien TW, Twu BW. The absorption kinetics of NO in NaClO2/NaOH solutions. JOURNAL OF HAZARDOUS MATERIALS 2001; 84:241-252. [PMID: 11406309 DOI: 10.1016/s0304-3894(01)00215-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A combined wet scrubbing SOx/NOx removal system is an advanced air pollution control process. In this process, the mechanism of NO removal is relatively unknown. Consequently, absorption of NO by alkaline solutions of NaClO2 was studied to clarify the reaction kinetics. The experiments were carried out mainly at temperature 50 degrees C which is the common operating temperature for wet scrubbers. The assumption that the absorption occurred under the fast pseudo-mth reaction regime was verified in the experiments. The absorption rate of NO into NaClO2 solutions was found to be proportional to P(2)NO,0 and [NaClO2]0(2). The addition of NaOH to solutions of NaClO2 decreased the absorption rate of NO. The absorption rate of NO at 25 degrees C is lower than at 50 degrees C. In the study, the absorption rate of NO did not change with changing gas flow rates.
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Chu H, Hua X, Gao Q, Cui Y. [Analysis of the reason that patients with chronic sinusitis having a negative CT manifestation]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2001; 15:195-6. [PMID: 12541758] [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 To explore the reason why the CT manifestation of the patients with chronic nasosinusitis is negative. METHOD To analyze the clinical and CT manifestation of the patients with chronic sinusitis having a negative CT manifestation. RESULT Pathological changes were found in all 8 patients during the course of endoscopic sinus surgery, such as pus storing in the sinus cavity, mucous swelling polypoidly, small polyps formation and so on. CONCLUSION The reasons that the patients with chronic sinusitis having a negative CT manifestation are, 1. CT scan can only give a static one-off image, 2. partial volume effect, 3. maybe result from the location of CT scan and the resolving power of tomograph, 4. maybe attribute to the pathological classify of chronic sinusitis.
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Chu H, Lee WT, Chiou YY, Tseng TK. The kinetics of catalytic incineration of C2H5SH and (CH3)2S2 over a Pt/Al2O3 catalyst. ENVIRONMENTAL TECHNOLOGY 2001; 22:515-522. [PMID: 11424728 DOI: 10.1080/09593330.2001.9619088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Catalytic incineration is one of the cost-effective technologies to solve the troublesome VOCs. However, some sulfur containing VOCs, such as ethyl mercaptan and dimethyl disulfide, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. The catalytic incineration of these compounds over a Pt/Al2O3 catalyst was carried out in a bench scale catalytic incinerator. Three kinetic models, such as power-rate law, Mars and Van Krevelen model, and Langmuir-Hinshelwood model were used to analyze the results. A differential reactor design was used for best fit of kinetic models in this study. The results show that the Langmuir-Hinshelwood model is feasible to describe the catalytic incineration of both C2H5SH and (CH3)2S2. This suggests that the chemical adsorption of O2 molecule is important in the process of catalytic incineration of C2H5SH and (CH3)2S2.
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Chu H, Hao GH, Tseng TK. The kinetics of catalytic incineration of dimethyl sulfide and dimethyl disulfide over an MnO/Fe2O3 catalyst. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2001; 51:574-581. [PMID: 11321914 DOI: 10.1080/10473289.2001.10464288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The catalytic incineration of dimethyl sulfide and dimethyl disulfide [(CH3)2S and (CH3)2S2] over an MnO/Fe2O3 catalyst was carried out in a bench-scale catalytic incinerator. Three kinetic models (i.e., the power-rate law, the Mars and Van Krevelen model, and the Langmuir-Hinshelwood model) were used to analyze the results. A differential reactor design was used for best fit of kinetic models in this study. The results show that the Langmuir-Hinshelwood model may be feasible to describe the catalytic incineration of (CH3)2S and (CH3)2S2. This suggests that the chemical adsorption of O2 molecules is important in this incineration.
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Chu H, Lee WT, Horng KH, Tseng TK. The catalytic incineration of (CH3)2S and its mixture with CH(3)SH over a Pt/Al(2)O(3) catalyst. JOURNAL OF HAZARDOUS MATERIALS 2001; 82:43-53. [PMID: 11165060 DOI: 10.1016/s0304-3894(00)00351-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Catalytic incineration is one of the cost-effective technologies to solve the troublesome volatile organic compounds (VOCs). However, some sulfur containing VOCs, such as dimethyl sulfide, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. This paper provides information on the poisoning effect of (CH3)2S. The catalytic incineration of (CH3)2S, typically emitted from the petrochemical industry, over a Pt/Al(2)O(3) fixed bed catalytic reactor was studied. The effects of operating parameters including inlet temperature, space velocity, (CH3)2S concentration, O2 concentration and catalyst size were characterized. Catalytic incineration on a mixture of (CH3)2S with CH(3)SH was also tested. The results show that the conversions of (CH3)2S increase as the inlet temperature increases and the space velocity decreases. The higher the (CH3)2S concentration is, the lower its conversion is. The O2 concentration has a positive effect on the conversion of (CH3)2S. (CH3)2S has a poisoning effect on the Pt/Al(2)O(3) catalyst, especially at lower temperatures. The conversion of (CH3)2S is significantly suppressed by the existence of CH(3)SH.
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Wang X, Liu Y, Li Z, Chu H, Sang X, Fan Q, Wang H. [Carrier detection and prenatal diagnosis for hemophilia A]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2001; 22:117-20. [PMID: 11877059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To establish a simple, rapid carrier detection and prenatal diagnosis system for hemophilia A. METHODS Intron 22 inversion in FVIII gene was directly examined by long distance polymerase chain reaction. Polymorphism of factor VIII intragenic RFLP of Bcl I, STR within intron 13 and 22, and extragenic DXS 52 (St 14) VNTR loci by hereditary linkage analysis were assayed. RESULTS The diagnostic rates of these loci were 47.6% (intron 22 inversion), 27.8% (Bcl I), 28.6% and 29.4% (STR within intron 13 and 22), and 81.3% (DXS52), respectively. The overall diagnostic rate in 21 families was 94.7%. CONCLUSIONS The diagnosis in hemophilia A patients or carriers can be made if intron 22 inversion is present. The intragenic and extragenic loci hereditary linkage analysis could be used to establish the diagnosis in intron 22 inversion negative patients.
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Li SF, Opsal J, Chu H, Aspnes DE. Detection and analysis of depolarization artifacts in rotating-compensator polarimeters. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2001; 18:426-434. [PMID: 11205990 DOI: 10.1364/josaa.18.000426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Absolute constraints, namely, the Schwarz inequality and a complementary expression derived by us, are used to obtain corresponding absolute constraints on the Fourier coefficients of the intensity transmitted through rotating-compensator polarimeters and ellipsometers. These expressions allow the investigation of artifacts that result in mixed or apparently mixed polarization states over the cross section of the beam, the averaging time of the detector, or the frequency passband of the dispersing element. Examples include multiple internal reflections or inhomogeneous strain within an element, scattered light, and other types of system and component defects that cannot be accessed by means of polarization-state data alone. We apply these results to our polarizer-sample-compensator-analyzer (PSCA) ellipsometer to illustrate capabilities. A simple analytic model is shown to give a quantitative description of depolarization in systems for which the resolution is finite and the retardation varies with wavelength.
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Chien TW, Chu H, Hsueh HT. Spray scrubbing of the nitrogen oxides into NaClO2 solution under acidic conditions. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2001; 36:403-414. [PMID: 11413827 DOI: 10.1081/ese-100103472] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The operating conditions of this study were closed to the typical operating conditions of flue gas desulfurization system in the coal-fired power plant. The objective of this study was to investigate the absorption performance of lean NO in an aqueous solution of acidic sodium chlorite using a bench-scale spraying column. The NO conversion and NOx removal efficiency were increasing with the increasing NO concentration, retention time, sodium chlorite concentration, operating temperature, and decreasing initial pH of solution. As the sodium chlorite concentration were higher than 0.4 M, the NO conversion and NOx removal efficiency were 100% and 80%, respectively. The NO conversion and NOx removal efficiency under initial pH 4-7 were higher than that of initial pH > 7. It meant that this process might be suitable to combining with traditional wet flue gas desulfurization system. As the NO2/NOx ratio in the effluent gas was closed to 0.5, it might be suitable to be absorbed in the second scrubbing column operated under alkaline condition.
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Chien TW, Chu H. Removal of SO2 and NO from flue gas by wet scrubbing using an aqueous NaClO2 solution. JOURNAL OF HAZARDOUS MATERIALS 2000; 80:43-57. [PMID: 11080568 DOI: 10.1016/s0304-3894(00)00274-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study used a NaClO2/NaOH solution as the additive/absorbent to determine the extent of NOx removal in a wet scrubbing system. A combined SOx/NOx removal system was also tested. The experiments were performed in a bench-scale spraying sieve tray wet scrubber in a continuous mode. The operating variables included NO and SO2 concentrations, L/G ratio, molar ratio, and initial pH. The results of the individual DeNOx experiments show that the maximum DeNOx efficiencies ranged from 3.1 to 12.6%. The results of the combined DeSOx/DeNOx experiments show that the maximum DeNOx and DeSOx efficiencies ranged from 36.6 to 71.9% and from 89.4 to 100.0%, respectively. The major parameters affecting NOx removal efficiencies are the L/G ratio and the dosage of additive. The major parameter influencing DeSOx efficiencies is the L/G ratio.
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Guo X, Wang H, Chu H, Wang X, Qu B, Li Z, Qi Z, Wang Z. [Retroviral-mediated high efficient in vitro expression of human coagulation factor VIII]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2000; 21:457-9. [PMID: 11877017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To develop a retroviral-mediated high efficient expression system of human coagulation factor VIII. METHODS The retroviral vector LNC-VIIIBD was generated by cloning a B-domain-deleted FVIII cDNA (760aa - 1639aa) into retroviral vector pLNCX. Several cell lines including NIH3T3, CHO, COS-7 and human hepatic cell line L-02 were infected with viral supernatant from the highest productive PA317 clones. The antigen and procoagulant activity of human FVIII in the cell culture medium were measured by ELISA assay and one-stage method, respectively. RT-PCR was performed for the detection of F VIII BD mRNA. RESULTS Human FVIII was expressed in all four target cells. The highest expression was observed in NIH3T3, the procoagulant activity of secreted FVIII was up to 1.6 U, and the FVIII antigen was 500 ng by 10(6) cells/ml in 24 hours, respectively. CONCLUSION The constructed retroviral vector was able to generate high level expression of human FVIII in some cell lines, and it might have potential utility in the gene therapy for Hemophilia A.
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145
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Hongo JS, Laramee GR, Urfer R, Shelton DL, Restivo T, Sadick M, Galloway A, Chu H, Winslow JW. Antibody binding regions on human nerve growth factor identified by homolog- and alanine-scanning mutagenesis. Hybridoma (Larchmt) 2000; 19:215-27. [PMID: 10952410 DOI: 10.1089/02724570050109611] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The binding specificities of a panel of mouse monoclonal antibodies (MAbs) to human nerve growth factor (hNGF) were determined by epitope mapping using chimeric and point mutants of NGF. Subsequently, the MAbs were used to probe NGF structure-function relationships. Six MAbs, which recognize distinct or partially overlapping regions of hNGF, were evaluated for their ability to block the binding of hNGF to the TrkA and p75 NGF receptors in various in vitro assays, which included blocking of TrkA autophosphorylation and blocking of NGF-dependent survival of dorsal root ganglion sensory neurons. Three MAbs (911,912,938) were potent blockers of all activities. Potent blocking of p75 binding occurs only with MAb 909, which recognizes an NGF region identified by mutagenesis as important for NGF-p75 binding. These results are consistent with recently proposed models of binding regions involved in NGF-TrkA and NGF-p75 interactions generated through mutagenic analysis and structure determination of the NGF-TrkA complex. These studies provide insight to the epitope specificities and potency of MAbs that would be useful for physiological NGF blocking studies.
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MESH Headings
- Alanine/genetics
- Animals
- Antibodies, Monoclonal/metabolism
- Binding Sites, Antibody/genetics
- Blotting, Western
- CHO Cells
- Cricetinae
- Humans
- Mutagenesis, Site-Directed
- Nerve Growth Factor/biosynthesis
- Nerve Growth Factor/genetics
- Nerve Growth Factor/metabolism
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- Point Mutation
- Protein Structure, Secondary/genetics
- Rats
- Receptor, Nerve Growth Factor/genetics
- Receptor, Nerve Growth Factor/metabolism
- Receptor, trkA/antagonists & inhibitors
- Receptor, trkA/genetics
- Receptor, trkA/immunology
- Receptor, trkA/metabolism
- Recombinant Proteins/immunology
- Recombinant Proteins/metabolism
- Transfection
- Tumor Cells, Cultured
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146
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Guo W, Wang H, Zhao W, Qu B, Pan L, Zhu J, Chu H, Wang X. [Mechanism of tissue factor expression on NB4 cells down-regulated by all-trans retinoic acid and arsenic trioxide]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2000; 21:240-3. [PMID: 11876987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To investigate molecular mechanism of tissue factor (TF) expression on acute promyelocytic leukemia cell line NB4 cells down-regulated by all-trans retinoic acid (ATRA) and arsenic trioxide (As(2)O(3)). METHODS Cyclohexamide (CHX) inhibition test for de novo protein synthesis and actinomycin D (Act D) inhibition test for RNA synthesis were used to check the effect of ATRA on the TF expression. TF antigen of U937 cells transfected with pMSCV-PML-RARalpha treated with or without ATRA and As(2)O(3) was detected. RESULTS CHX treatment completely suppressed the down-regulation effect of ATRA on the TF mRNA expression, Act D inhibition test showed that half-life of TF mRNA in treated NB4 cells was shortened to about 30 min from that of around 60 min in untreated NB4 cells. The TF antigen contents in U937 cells transfected with pMSCV-PML-RARalpha were significantly higher than that in transfected U937 cells with retrovirus vector. Both ATRA and As(2)O(3) could down-regulate the TF antigen level in U937 cells transfected with or without PML-RARalpha. CONCLUSION The modulation of the TF mRNA expression in NB4 cells by ATRA might be indirect. TF mRNA destabilization was involved in the TF regulation process mediated by ATRA. Elevated TF antigen level in U937 cells transfected with pMSCV-PML-RARalpha may be related to the fusion protein PML-RARalpha. The down-regulation effect of ATRA and As(2)O(3) on the TF expression of U937 cells might not involve the fusion protein.
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Li Z, Wang X, Wang H, Guo W, Liu Y, Qu B, Guo X, Chu H. [Effects of holothuria glycosaminoglycan on the expression of tissue factor and thrombomodulin in stimulated endothelial cells]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2000; 21:201-4. [PMID: 11876983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
OBJECTIVE To study the mechanism of antithrombotic effects of holothuria glycosaminoglycan (GAG). METHODS Endothelial cells from human umbilical vein which were pre-induced with 1 mg/L lipopolysaccharide, were treated by GAG (1 mg/L, 5 mg/L, and 10 mg/L, respectively) and 5 mg/L heparin as a control for 6 hours. Procoagulant activity (PCA), the expressions of tissue factor (TF) antigen and thrombomodulin (TM) antigen and their mRNA transcriptions were investigated. RESULTS GAG could down-regulate the expression of TF antigen and mRNA, up-regulate the expression of TM antigen and mRNA, down-regulate the PCA of stimulated endothelial cells. CONCLUSION Down-regulating TF expression and up-regulating TM expression of stimulated endothelial cells may be one of the mechanisms of GAG antithrombosis.
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148
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Chu H, Chen X. [A study on the relationship between serum free alpha-subunit of human chorionic gonadotropin and pregnancy induced hypertension]. ZHONGHUA FU CHAN KE ZA ZHI 2000; 35:148-50. [PMID: 11775891] [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 determine the correlation of free alpha subunit of human chorionic gonadotropin (F alpha-hCG) with pregnancy induced hypertension(PIH), and to observe the immunohistochemical expression of alpha-hCG in placentae from PIH. METHODS Serum was obtained from 66 successive pregnant women diagnosed with PIH (5 mild, 8 middle and 53 severe) at 21-43 weeks' gestation. A group of 30 non PIH gravid women were used as controls. The serum was assayed for F alpha-hCG by monoclonal technology and human prolactin was assayed for correcting the blood contraction. Immunolocalization and the intensity of the immunohistochemical stained in the placentae from 13 PIH and 13 normal pregnancies. RESULTS Significant difference was noted between the two groups mean of F alpha-hCG (the control group VS PIH group was 528 +/- 421 IU/L VS 222 +/- 129 IU/L, P < 0.001); no significant between two groups of hPL. The mean value of F alpha-hCG of severe PIH revealed significantly higher than the mild and moderate (569 +/- 455 IU/L VS 363 +/- 159 IU/L, P < 0.01); The leve of F alpha-hCG in group of proteinuria > or = +++ was higher than that of proteinuria < +++ (598 +/- 474 IU/L VS 425 +/- 291 IU/L, P > 0.05). The intensity of alpha-hCG immunostaining in syncytiotrophoblast was significantly increased in 13 PIH compared with the control group (the strong positive rate 10/13 VS 3/13 P < 0.025). CONCLUSIONS The level of F alpha-hCG are significantly higher in PIH compared with controls. The more severe the higher level of F alpha-hCG is in PIH. The higher level of alpha-hCG has the basement of placentae pathology.
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Pearson TA, Laurora I, Chu H, Kafonek S. The lipid treatment assessment project (L-TAP): a multicenter survey to evaluate the percentages of dyslipidemic patients receiving lipid-lowering therapy and achieving low-density lipoprotein cholesterol goals. ARCHIVES OF INTERNAL MEDICINE 2000; 160:459-67. [PMID: 10695686 DOI: 10.1001/archinte.160.4.459] [Citation(s) in RCA: 802] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To determine the percentage of patients in the multicenter Lipid Treatment Assessment Project receiving lipid-lowering therapy who are achieving low-density lipoprotein cholesterol (LDL-C) goals as defined by National Cholesterol Education Program (NCEP) guidelines. METHODS Adult patients with dyslipidemia, who had been receiving the same lipid-lowering therapy for at least 3 months, were assessed at investigation sites. Lipid levels were determined once in each patient at the time of enrollment. The primary end point was the success rate, defined as the proportion of patients who achieved their LDL-C target level as specified by NCEP guidelines. RESULTS A total of 4888 patients from 5 regions of the United States were studied. Of these, 23% had fewer than 2 risk factors for coronary heart disease (CHD) and no evidence of CHD (low-risk group), 47% had 2 or more risk factors and no evidence of CHD (high-risk group), and 30% had established CHD. Overall, only 38% of patients achieved NCEP-specified LDL-C target levels; success rates were 68% among low-risk patients, 37% among high-risk patents, and 18% among patients with CHD. Drug therapy was significantly (P< or =.001) more effective than nondrug therapy in all patient risk groups. However, many patients treated with lipid-lowering drugs did not achieve LDL-C target levels. CONCLUSIONS Large proportions of dyslipidemic patients receiving lipid-lowering therapy are not achieving NCEP LDL-C target levels. These findings indicate that more aggressive treatment of dyslipidemia is needed to attain goals established by NCEP guidelines.
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Gazzano-Santoro H, Chen A, Casto B, Chu H, Gilkerson E, Mukku V, Canova-Davis E, Kotts C. Validation of a rat pheochromocytoma (PC12)-based cell survival assay for determining biological potency of recombinant human nerve growth factor. J Pharm Biomed Anal 1999; 21:945-59. [PMID: 10703962 DOI: 10.1016/s0731-7085(99)00225-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A method has been validated, according to the Guidelines of the International Conference on Harmonization (ICH), for precise quantitation of the biological activity of recombinant human nerve growth factor (rhNGF) for lot release testing. The assay is based on the survival of a subclone of rat pheochromocytoma PC12 cells (PC12-CF) in response to rhNGF. Cell survival is measured by monitoring the reduction, by living cells, of the alamarBlue dye into a red form which is highly fluorescent. The assay is simple, has high throughput (performed in 96-well microtiter plates) and shows reproducible dose-response curves in the concentration range of 0.2-50 ng/ml. The method was validated for its linearity, accuracy, precision, robustness, and to meet current regulatory requirements. The assay demonstrated good linearity, yielding a coefficient of determination of 0.9902. Sample recovery studies demonstrated an accuracy ranging from 96 to 98%. The repeatability of the assay and intermediate precision had coefficients of variation (CV) of <9%. The assay was stability-indicating since it was able to detect changes in rhNGF samples degraded by protease treatment and in a number of isolated rhNGF variants. Robustness was demonstrated by the relative insensitivity of the assay to small deliberate changes in key method parameters. The validation data, provided in this manuscript, indicate that the newly described bioassay for rhNGF is robust, accurate, precise, and suitable for lot release potency testing of rhNGF.
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