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Chiang CF, Lu CJ, Sung LK, Wu YS. Full-scale evaluation of heat balance for autothermal thermophilic aerobic treatment of food processing wastewater. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2001; 43:251-258. [PMID: 11443970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A full-scale autothermal thermophilic aerobic treatment (ATAT) of food-processing wastewater was evaluated in this study. The wastewater was rich in oil and grease at concentrations of 1,500-2,000 mg/L. The system has been operated for more than one and a half years since the startup. Under steady state conditions, the ATAT process was capable of spontaneous reaction at temperatures of 45-55 degrees C without the addition of external heat. Treatment efficiency was as high as 95% in COD reduction at a volumetric COD loading of 4.1 kg/m3-d. A mathematical heat balance model was developed based on the theoretical considerations of heat sources and losses for the ATAT process. A computer algorithm was established to evaluate specific heat potential (Hs) of the wastewater under steady state conditions. Six months of steady-state data were used for the evaluation. The result shows that on average the wastewater had a specific heat potential (Hs) of 4,720 kcal/kg-COD removed and the biological heat contributed 41.4% of the total heat input. A net heat flux of 4,270 kcal/min and volumetric heat intensity (Hv) of 38.0 kcal/L was necessary to maintain reaction temperature at 48.2 degrees C for the ATAT process. The full-scale ATAT process showed the typical characteristics of high removal rate, low sludge yield, and poor solids settleability for thermophilic aerobic treatment reported in the literature.
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Fang GC, Chang CN, Wang NP, Wu YS, Wang V, Fu PP, Cheng CD, Chen SC, Lin DY. The study of TSP, PM(2.5-10) and PM2.5 during Taiwan Chi-Chi Earthquake in the traffic site of central Taiwan, Taichung. CHEMOSPHERE 2000; 41:1727-1731. [PMID: 11057611 DOI: 10.1016/s0045-6535(00)00055-2] [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
Ambient particle concentration was taken on the traffic sampling site over the Chung-Chi Road over bridge (CCROB) in front of Hungkuang Institute of Technology (HKIT). The sampling time was from August 1999 to December 1999. During the sampling period, Taiwan's biggest earthquake in more than a century registered 7.3 on the Richter scale (Taiwan Chi-Chi Earthquake). Besides, there were more than 20,000 aftershocks that followed the Taiwan Chi-Chi Earthquake within three months. Thus, the PM2.5, PM(2.5-10) particle concentrations were also collected then and compared with total suspended particle (TSP) in this study. The average PM(2.5-10), PM2.5 and TSP concentrations are 24.6, 58.0 and 106 microg/m3, respectively, after the Taiwan Chi-Chi Earthquake. The average TSP concentrations before and after Taiwan Chi-Chi Earthquake were 70 and 127 microg/m3, respectively. It is clearly shown that the average concentration of TSP after Taiwan Chi-Chi Earthquake was about 1.8 times as that of TSP concentration before Taiwan Chi-Chi Earthquake in the traffic site of central Taiwan. And the ratios of PM2.5/PM(2.5-10), PM2.5/PM10 and PM2.5/TSP are 2.2%, 67.2%, 38.9%, respectively. The results also indicated about Chi-Chi fine particle concentration (PM25) and the TSP increases in the traffic site of central Taiwan after Taiwan Chi-Chi Earthquake.
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Fang GC, Chang CN, Wu YS, Wang NP, Wang V, Fu PP, Yang DG, Che SC. Comparison of particulate mass, chemical species for urban, suburban and rural areas in central Taiwan, Taichung. CHEMOSPHERE 2000; 41:1349-1359. [PMID: 11057571 DOI: 10.1016/s0045-6535(00)00003-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Aerosol samples for PM2.5, PM(2.5-10) and TSP were collected from June to September 1998 and from February to March 1999 in central Taiwan. Ion chromatography was used to analyze the acidic anions: sulfate, nitrate and chloride in the Universal samples. The ratios of fine particle concentrations to coarse particle concentrations displayed that the fine particle concentrations are almost greater than that of coarse particle concentrations in Taichung area. The average concentrations of PM2.5, PM(2.5-10) and TSP in urban sites are higher than in suburban and rural sites at both daytime and night-time. Chloride dominated in the coarse mode in daytime and in fine mode in night-time. Nitrate can be found in both the coarse and fine modes. Sulfate dominated in fine mode in both daytime and night-time.
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Fang GC, Chang CN, Wu YS, Wang V, Fu PP, Yang DG, Chen SC, Chu CC. The study of fine and coarse particles, and metallic elements for the daytime and night-time in a suburban area of central Taiwan, Taichung. CHEMOSPHERE 2000; 41:639-644. [PMID: 10834362 DOI: 10.1016/s0045-6535(99)00507-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Daily average concentrations of fine and coarse particulates, and TSP samples have been measured simultaneously at daytime and night-time periods by using Universal and PS-1 sampler in a suburban area of central Taiwan from June to August 1998. The samples were analyzed by atomic absorption spectrometry to determine the fine and coarse particulate concentrations of metallic elements (Ca, Fe, Mn, Pb, Cu, Zn and Cr). The concentration of PM2.5 and TSP showed a decreased trend for the daytime period. The fine particle concentrations were about two times as that of coarse particulate concentrations. The averaged fine particulate concentrations at daytime are higher than at night-time. Ca and Fe were mostly in the coarse particulate mode. The correlation coefficients were 0.63 and 0.69 for elements Ca and Fe in the coarse particle mode for day and night periods. Pb showed a similar distribution ratio with Mn for the fine to coarse particle ratios at both day and night period. Pb and Mn are highly correlated for the day (R = 0.78) and night period (R = 0.61) at particle size <2.5 microm. Cu and Zn were mainly in fine particles at both day and night period. Fe and Ca consist of the major parts of all the elements. Elemental Mn is the lowest among the rest of the heavy metals.
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Wu YS, Wang Y, Huang CH, Lan FH, Zhu ZY. A compound heterozygote in the NADH-cytochrome b5 reductase gene from a Chinese patient with hereditary methemoglobinemia type I. Int J Hematol 2000; 72:34-6. [PMID: 10979206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
To elucidate the mutation in the nicotinamide adenine dinucleotide-cytochrome b5 reductase (b5R) gene from a Chinese patient with hereditary methemoglobinemia type I, we analyzed the coding sequences of b5R cDNA from the patient and from normal subjects by direct sequencing the reverse transcriptase-polymerase chain reaction (RT-PCR) products. The PCR-amplified genomic DNA fragments of the b5R gene from the patient, his mother, and normal controls were analyzed by restriction enzymes MspI and RsaI. A compound heterozygote Arg57Gln (CGG-->CAG)/Cys203Tyr (TGC-->TAC) was found in the b5R gene from the patient, and a CGG-->CAG mutant allele occurred in a chromosome inherited from his mother, while TGC-->TAC occurred in a chromosome inherited from his father. In this report, we discuss a compound heterozygote first observed in the b5R gene from a patient with hereditary methemoglobinemia type I.
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Wang Y, Wu YS, Zheng PZ, Yang WX, Fang GA, Tang YC, Xie F, Lan FH, Zhu ZY. A novel mutation in the NADH-cytochrome b5 reductase gene of a Chinese patient with recessive congenital methemoglobinemia. Blood 2000; 95:3250-5. [PMID: 10807796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Recessive congenital methemoglobinemia due to nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase (b5R) deficiency is classified into 2 clinical types: type 1 (erythrocyte type) and type 2 (generalized type). We found a Chinese family with type 1 recessive congenital methemoglobinemia, the patients from which were diagnosed according to clinical symptoms and b5R enzyme activity in the blood cells. To learn the molecular basis of type 1 recessive congenital methemoglobinemia in this Chinese family, we isolated total RNA from the peripheral leukocytes of the propositus and b5R complementary DNA (cDNA) by reverse transcription- polymerase chain reaction (RT-PCR). The coding region of the b5R cDNA was analyzed by sequencing the cloned PCR products. The results showed that the propositus was homozygous for a G-->A transition at codon 203 in exon 7, changing a cysteine to a tyrosine (Cys203Tyr). To characterize the mutant enzyme, both glutathione S-transferase (GST)-fused wild-type b5R and GST-fused mutant Cys203Tyr b5R were expressed in Escherichia coli and affinity purified. The results showed that the catalytic activity of the enzyme was not much affected by this amino acid substitution, but the mutant enzyme exhibited decreased heat stability and increased susceptibility to trypsin. These properties of the mutant enzyme would account for the restricted b5R deficiency and mild clinical manifestations of these type 1 patients. The finding of this novel mutation makes codon 203 the only position within the b5R gene at which more than 1 mutation has been found.
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Wu YS, Lee HK, Li SF. Simultaneous chiral separation of triadimefon and triadimenol by sulfated beta-cyclodextrin-mediated capillary electrophoresis. Electrophoresis 2000; 21:1611-9. [PMID: 10832895 DOI: 10.1002/(sici)1522-2683(20000501)21:8<1611::aid-elps1611>3.0.co;2-u] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Enantiomeric separation of two triazole fungicides, triadimefon and triadimenol, was investigated in sulfated beta-cyclodextrin (sulfated beta-CD)-mediated capillary electrophoresis (CE) systems. It was found that, at pH 2-4, sulfated beta-CD exhibited strong chiral recognition towards both triadimefon and triadimenol. The enantiorecognition was believed to result from the multiple interactions between sulfated beta-CD and the analytes, which included inclusion effect, electrostatic interaction, and hydrogen bonding. Under optimal conditions (phosphate buffer with 2% sulfated beta-CD, pH 2.5), simultaneous resolution of all chiral isomers of triadimefon and triadimenol was achieved in less than half an hour. In conjunction with solvent extraction and subsequent enrichment by solid-phase extraction (SPE), this new enantioseparation method was applied successfully in the study of stereoselectivity associated with the biotransformation of triadimefon to triadimenol by soil microorganisms. The present methodology was superior to the commonly adopted chiral gas chromatography (GC) approach in that a very mild procedure was involved from sample extraction to the ultimate chiral separation. Thus, the disturbance of the enantiomeric distribution patterns of the original soil samples by heat stress was an unlikely scenario. Furthermore, it was discovered that, owing to the unique selectivity of the present separation strategy, there was virtually no interference from the soil matrix, which led to improvements in both sensitivity and selectivity in real sample determination.
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Li M, Wu YS. Holography and noncommutative yang-mills theory. PHYSICAL REVIEW LETTERS 2000; 84:2084-2087. [PMID: 11017215 DOI: 10.1103/physrevlett.84.2084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/1999] [Indexed: 05/23/2023]
Abstract
In this Letter a recently proposed gravity dual of noncommutative Yang-Mills theory is derived from the relations between closed string moduli and open string moduli recently suggested by Seiberg and Witten. The only new input one needs is a simple form of the running string tension as a function of energy. This derivation provides convincing evidence that string theory integrates with the holographical principle and demonstrates a direct link between noncommutative Yang-Mills theory and holography.
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Fang GC, Chang CN, Wu YS, Fu PP, Yang DG, Chu CC. Characterization of chemical species in PM2.5 and PM10 aerosols in suburban and rural sites of central Taiwan. THE SCIENCE OF THE TOTAL ENVIRONMENT 1999; 234:203-12. [PMID: 10507159 DOI: 10.1016/s0048-9697(99)00276-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Aerosol samples for PM2.5 (particulate matter with aerodynamic diameters less than 2.5 microns), PM2.5-10 (particulate matter with aerodynamic diameters between 2.5 and 10 microns) and TSP were collected from June to September 1998 at THU (suburban) and HKIT (rural) sites in central Taiwan. The ratios of PM2.5/PM10 averaged 0.70 for the daytime and 0.63 for the nighttime at THU, respectively. At HKIT, the PM2.5/PM10 ratios averaged 0.56 for the daytime and 0.72 in the nighttime, respectively. These results indicated that the PM2.5 concentrations contribute the majority of the PM10 concentration and PM10 concentrations contribute the majority of the TSP at both sites. The averaged PM2.5 concentrations at THU are higher than those measured at HKIT during the daytime period. However, the average PM2.5-10 concentrations in THU are lower than those measured at HKIT during nighttime. The samples collected were also analyzed by atomic absorption spectrophotometry for the elemental analysis of Ca, Fe, Pb, Zn, Cu, Mn and Cr. Meanwhile ion chromatography was used to analyze for the water-soluble ions: sulphate, nitrate and chloride in the Universal samples. The concentrations of heavy metals in PM10 during daytime were all higher than nighttime at THU. However, the averaged concentrations of metal elements in PM10 during day and night period were distributed irregularly at HKIT. The results indicated that for metal elements collected at HKIT have different emission sources. The concentrations of metal elements during daytime in PM10 at THU were generally higher than HKIT. The phenomena owing to the averaged PM2.5 particle concentrations at THU (suburban) were higher than those measured at HKIT (rural) and PM2.5 occupied the major portions of PM10 for both sites during the day period. For anion species, there are no significant differences between day and night period in PM10 concentrations at both suburban and rural sites.
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Fang GC, Chang CN, Wu YS, Fu PC, Chang KF, Yang DG. The characteristic study of TSP, PM2.5-10 and PM2.5 in the rural site of central Taiwan. THE SCIENCE OF THE TOTAL ENVIRONMENT 1999; 232:177-84. [PMID: 10481294 DOI: 10.1016/s0048-9697(99)00092-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
The total suspended particle (TSP), PM2.5-10 (aerodynamic diameter less than 10 microns) and PM2.5 concentration (aerodynamic diameter less than 2.5 microns) concentrations were sampled by PS-1 and Universal sampler on the roof (25 m) of the Medical and Engineering Building in the campus of Hungkuang Institute of Technology (HKIT) which is located at a height of 500 m on Da Du Mountain. The results indicated that average TSP, PM2.5-10 and PM2.5 concentrations are 0.42, 0.34 and 0.019 mg/m3 in the day time, respectively and are 0.32, 0.26 and 0.017 mg/m3 in the night time, respectively. The ratios of PM2.5-10/TSP were from 76% to 85% and from 50% to 91% for day and night period, respectively. It indicated that the major composition in the total suspended particles was PM2.5-10 in the rural site. The relationship between TSP and PM2.5-10 is TSP = 1.16PM2.5-10 + 0.027 and TSP = 1.01 PM2.5-10 + 0.058 in the day and night time, respectively. The correlation coefficient (R2) is 0.98 and 0.97 for day and night period, respectively. The relationship between PM2.5-10 and PM2.5 is PM2.5 = 0.0005PM2.5-10 + 0.019 and PM2.5 = 0.037PM2.5-10 + 0.0076 in the day and night period, respectively. The correlation coefficient (R2) is 3E-5 and 0.67 for day and night period, respectively. The relationships between TSP, PM2.5-10, PM2.5 particle concentrations and wind speed (R2) in the day time are 0.71, 0.64, 0.43, respectively and are 0.83, 0.79, 0.57, respectively in the night time. The proposed reasons are that there are more activities caused by people (students) and natural living animals which absorbed some of the particles during the day time. Thus, the correlation coefficients for the night time are better than those of day time. The particle size distributions are both bimodel in the day and night time. The major peaks in the day time appear in the particle diameter between 0.031-0.056 micron and 3.16-5.62 microns in the day period and appear between 0.017-0.031 micron and 1.78-3.16 microns in the night period. The results indicate that the particle size distribution in the day time tends to be of larger particle size mode than the night time.
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Cheng FC, Tsai TH, Wu YS, Kuo JS, Chen CF. Pharmacokinetic and pharmacodynamic analyses of trazodone in rat striatum by in vivo microdialysis. J Pharm Biomed Anal 1999; 19:293-300. [PMID: 10704094 DOI: 10.1016/s0731-7085(98)00117-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The aim of this study was to investigate the brain pharmacokinetics and pharmacodynamics of trazodone. Sensitive microbore high-performance liquid chromatographic methods with electrochemical detection (LC-ED) were developed for the determination of trazodone, serotonin (5-HT), and their respective metabolites. The feasibility of microdialysis coupled with LC-ED system for direct analysis of these compounds in the rat striatum was investigated. Striatal dialysates were automatically injected onto a cyano microbore column, through an on-line injector, for the determination of trazodone and its metabolite or onto a reversed phase microbore column for the determination of 5-HT and its metabolite. A monophase phenomenon with a first-order elimination rate constant was observed for trazodone. The brain pharmacokinetics of trazodone appear to conform to a one-compartment model. Surprisingly, no significant changes in striatal 5-HT or its metabolite were observed following the same dosage and time course. The present results suggest that brain microdialysis methods may be applicable to pharmacokinetic and pharmacodynamic studies of psychotrophic agents.
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Wu YS, Salmela KS, Lieber CS. Microsomal acetaldehyde oxidation is negligible in the presence of ethanol. Alcohol Clin Exp Res 1998; 22:1165-9. [PMID: 9726291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The microsomal ethanol oxidizing system (MEOS), inducible by ethanol and acetone, oxidizes ethanol to acetaldehyde, which causes many toxic effects associated with excess ethanol. Recent studies reported that rat liver microsomes also oxidize acetaldehyde, thereby challenging the validity of the assessment of MEOS activity by measuring acetaldehyde production and suggesting that MEOS activity results in the accumulation not of acetaldehyde but, rather, of its less toxic metabolite, acetate. To address these issues, we compared both metabolic rates of ethanol and acetaldehyde and the effect of ethanol on the acetaldehyde metabolism. Liver microsomes were prepared from Sprague-Dawley rats induced either with acetone for 3 days or ethanol for 3 weeks. NADPH-dependent acetaldehyde (300 microM) metabolism was measured in two ways: (1) by detection of acetaldehyde disappearance by headspace gas chromatography, and (2) by assessment of acetaldehyde oxidation by liquid scintillation counting of acetate formed from [1,2-14C]acetaldehyde. Ethanol (50 mM) oxidation was measured by gas chromatography. In acetone- and ethanol-induced rat liver microsomes, the acetaldehyde disappearance (p < 0.0001) and oxidation (p < 0.0001) rates were both significantly increased. The rates of acetaldehyde oxidation paralleled those of p-nitrophenol hydroxylation (r = 0.974, p < 0.0001), with a Km of 82+/-14 microM and a Vmax of 4.8+/-0.5 nmol/min/mg protein in acetone-induced microsomes. Acetaldehyde disappearance in acetone-induced microsomes and acetaldehyde oxidation in acetone-induced and ethanol-induced microsomes were significantly lower than the corresponding ethanol oxidation, with rates (nmol/min/mg protein) of 4.6+/-0.6 versus 9.0+/-0.8 (p < 0.005), 4.4+/-0.3 versus 9.1+/-0.5 (p < 0.0005), and 14.0+/-0.9 versus 19.5+/-1.8 (p < 0.05), respectively. The presence of 50 mM ethanol decreased this metabolism to 0.9+/-0.3 (p < 0.005), 0.5+/-0.1 (p < 0.001), and 1.8+/-0.3 (p < 0.001), resulting in rates of acetaldehyde metabolism of only 9.8+/-3.2%, 6.0+/-0.5%, and 9.5+/-1.2% (respectively) of those of ethanol oxidation. In conclusion, rat liver microsomes oxidize acetaldehyde at much lower rates than ethanol, and this acetaldehyde metabolism is strikingly inhibited by ethanol. Accordingly, acetaldehyde formation provides an accurate assessment of MEOS activity. Furthermore, because acetaldehyde production vastly exceeds its oxidation, the net result of MEOS activity is the accumulation of this toxic metabolite.
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Wu YS, Lee HK, Li SF. Rapid estimation of octanol-water partition coefficients of pesticides by micellar electrokinetic chromatography. Electrophoresis 1998; 19:1719-27. [PMID: 9719551 DOI: 10.1002/elps.1150191032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Micellar electrokinetic chromatography (MEKC) was evaluated as a new technique for the rapid estimation of octanol-water partition coefficient (logKow). Retention measurements for more than 40 reference pesticides with varied structural characteristics and hydrophobicity were carried out in two MEKC systems, based on sodium dodecyl sulfate (SDS) and sodium cholate (SC), respectively. To enable an accurate determination of capacity factors in the SC-MEKC system, cypermethrin (a synthetic pyrethroid insecticide) was utilized instead of Sudan III as the SC micelle tracer, since a few highly hydrophobic pesticides were found to elute after Sudan III. The linear correlation between logarithmic capacity factor (logk') and logKow in the two systems was examined. It was found that, under the typical buffer condition (10 mM sodium phosphate with 60 mM surfactant, pH 7.0), the SDS-MEKC system provided a somewhat wider dynamic range for hydrophobicity (logKow from -1.0 to 4.5). However, the correlation of logk' with logKow was not very high when all the reference pesticides were included in one single calibration set. For the SC-MEKC system, the dynamic range for logKow was in the range of 1.0-5.5, and a good linear correlation existed between logk' and logKow, even when all reference pesticides were incorporated into a single calibration group. By comparing the regression line of the reference pesticides with that of a group of simple aromatic derivatives, it was discovered that molecular size and functionality posed a less significant effect on the measurement of logKow in the SC-MEKC system than in the SDS-MEKC system. Thus, SC-MEKC shall be the system of choice for the estimation of logKow. The typical error on logKow determination using the current MEKC technique was within 0.5 units, suggesting that MEKC can be a valuable complement to reversed phase high performance liquid chromatography (RP-HPLC) for the indirect determination of logKow. Besides maintaining all the advantages of the HPLC approach, the MEKC technique showed some unique benefits, such as better inter-column reproducibility, higher throughput, and less handling of toxic pesticides and solvents.
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Zheng D, Gordon LA, Wu YS, Feigelson RS, Fejer MM, Byer RL, Vodopyanov KL. 16-microm infrared generation by difference-frequency mixing in diffusion-bonded-stacked GaAs. OPTICS LETTERS 1998; 23:1010-1012. [PMID: 18087412 DOI: 10.1364/ol.23.001010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Tunable 90-ps 15.6-17.6-microm coherent radiation was generated by means of difference-frequency mixing in diffusion-bonded-stacked GaAs. The sample consisted of 24 alternately rotated layers with a total length of 6 mm and with low optical loss to achieve third-order quasi-phase matching. The wavelength-tuning curve was close to the theoretical prediction, demonstrating that the bonding process maintained nonlinear optical phase matching over the entire interaction length. Maximum conversion efficiency of 0.7%, or 5% internal quantum efficiency, was measured at 16.6 microm, consistent with the theoretical predictions.
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Wu YS, Huang CH, Wan Y, Huang QJ, Zhu ZY. Identification of a novel point mutation (Leu72Pro) in the NADH-cytochrome b5 reductase gene of a patient with hereditary methaemoglobinaemia type I. Br J Haematol 1998; 102:575-7. [PMID: 9695975 DOI: 10.1046/j.1365-2141.1998.00782.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Utilizing polymerase chain reaction (PCR) related technology, we investigated the b5R gene of a Chinese patient with hereditary methaemoglobinaemia type I and found a novel missense mutation (CTC-CCC) at codon 72 in exon 3 of the gene. As the mutation generates an Apa I recognition site, homozygosity for the mutation was confirmed by restriction analysis of PCR-amplified fragments from the patient's genomic DNA. We predicted that the residue replacement of Leu with Pro of the mutant enzyme would account for the b5R deficiency in the patient. The results further confirm the genetic polymorphism of b5R gene mutations found in the RCM type I.
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Lan FH, Tang YC, Huang CH, Wu YS, Zhu ZY. Antibody-based spot test for NADH-cytochrome b5 reductase activity for the laboratory diagnosis of congenital methemoglobinemia. Clin Chim Acta 1998; 273:13-20. [PMID: 9620466 DOI: 10.1016/s0009-8981(98)00022-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
NADH (reduced Coenzyme I)-cytochrome b5 reductase (b5R) is a multifunctional redox enzyme, whose deficiency causes recessive congenital methemoglobinemia. A novel procedure for the detection of b5R activity in human hemolysates was developed, in which b5R monoclonal antibodies dot-blotted on nitrocellulose membrane was used to capture and enrich b5R from hemolysates, and the captured b5R activity was subsequently visualized with the substrate 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide. Application of this simple method to the detection of b5R activity in the hemolysates from different subjects demonstrated that it was both sensitive and reliable. Our method would be useful for the laboratory diagnosis of congenital methemoglobinemia.
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Vaziri H, West MD, Allsopp RC, Davison TS, Wu YS, Arrowsmith CH, Poirier GG, Benchimol S. ATM-dependent telomere loss in aging human diploid fibroblasts and DNA damage lead to the post-translational activation of p53 protein involving poly(ADP-ribose) polymerase. EMBO J 1997; 16:6018-33. [PMID: 9312059 PMCID: PMC1170232 DOI: 10.1093/emboj/16.19.6018] [Citation(s) in RCA: 263] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Telomere loss has been proposed as a mechanism for counting cell divisions during aging in normal somatic cells. How such a mitotic clock initiates the intracellular signalling events that culminate in G1 cell cycle arrest and senescence to restrict the lifespan of normal human cells is not known. We investigated the possibility that critically short telomere length activates a DNA damage response pathway involving p53 and p21(WAF1) in aging cells. We show that the DNA binding and transcriptional activity of p53 protein increases with cell age in the absence of any marked increase in the level of p53 protein, and that p21(WAF1) promoter activity in senescent cells is dependent on both p53 and the transcriptional co-activator p300. Moreover, we detected increased specific activity of p53 protein in AT fibroblasts, which exhibit accelerated telomere loss and undergo premature senescence, compared with normal fibroblasts. We investigated the possibility that poly(ADP-ribose) polymerase is involved in the post-translational activation of p53 protein in aging cells. We show that p53 protein can associate with PARP and inhibition of PARP activity leads to abrogation of p21 and mdm2 expression in response to DNA damage. Moreover, inhibition of PARP activity leads to extension of cellular lifespan. In contrast, hyperoxia, an activator of PARP, is associated with accelerated telomere loss, activation of p53 and premature senescence. We propose that p53 is post-translationally activated not only in response to DNA damage but also in response to the critical shortening of telomeres that occurs during cellular aging.
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Wu YS, Ho WM, Tsai TH, Yang LL, Kuo JS, Cheng FC. Monitoring of blood catecholamines by microdialysis and microbore LC with a dual amperometric detector. J Pharm Biomed Anal 1997; 16:77-85. [PMID: 9447554 DOI: 10.1016/s0731-7085(96)02054-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The accuracy of in vivo microdialysis for monitoring blood catecholamines and their metabolites in Lan-Yu mini-pigs was evaluated. To prevent blood clots and irritation, a microdialysis probe was secured in a Y-shaped tube. The tube was connected to an arterio-venous shunt, in a mini-pig, for in vivo experiments. Perfusates were injected onto a microbore LC equipped with a dual electrochemical detector (the upstream electrode was set at an oxidizing potential and the downstream electrode was set at a reducing potential. The typical large offscale peak or interfering peaks on the anodic chromatograms were mostly eliminated on the cathodic chromatograms, thereby providing reliable measurements of early eluters. Early eluates, such as norepinephrine and epinephrine, with reversible redox behaviour could be detected at the downstream reducing electrode. A comparison of the present method and a conventional blood-drawing method showed good correlation (r = 0.775-0.983 for all analytes).
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Hu M, Wu YS, Wu HW. Effects of lithium deficiency in some insulin-sensitive tissues of diabetic Chinese hamsters. Biol Trace Elem Res 1997; 58:91-102. [PMID: 9363324 DOI: 10.1007/bf02910670] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In this work, we report the effect of low-dose lithium carbonate on blood glucose levels and tissue lithium content in hereditary spontaneous diabetic Chinese hamsters (HSDCHs). Hepatic lithium levels are significantly lower in diabetic hamsters when compared to healthy controls: 2.05 +/- 0.26 and 3.04 +/- 0.11 micrograms/g, respectively. The same trend was observed in kidney and muscle: 18.26 +/- 0.24 vs 20.23 +/- 1.10 micrograms/g and 4.66 +/- 0.17 vs 5.95 +/- 0.67 micrograms/g, respectively. The significance level was p < 0.05 in all cases. Supplementation with lithium carbonate eliminated tissue lithium deficiency, and had a normalizing effect on blood glucose and glycosylated serum protein levels. The insulin sensitivity index (ISI) increased, thus reducing insulin resistance. Our results suggest that lithium deficiency in certain insulin-sensitive tissues may be associated with blood glucose imbalance resulting from insulin resistance.
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Fu PP, Qui FY, Jung H, Von Tungeln LS, Zhan DJ, Lee MJ, Wu YS, Heflich RH. Metabolism of isomeric nitrobenzo[a]pyrenes leading to DNA adducts and mutagenesis. Mutat Res 1997; 376:43-51. [PMID: 9202737 DOI: 10.1016/s0027-5107(97)00024-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have been interested in determining the structural and electronic features that may be useful in predicting the mutagenic activity of nitro-polycyclic aromatic hydrocarbons (nitro-PAHs). We have previously found that a correlation between structural and electronic features and direct-acting mutagenicity in Salmonella typhimurium cannot be made using nitro-PAHs with different molecular size. In this study, a series of structurally related nitro-PAHs, the environmental contaminants 1-, 3-, and 6-nitrobenzo[alpha]pyrene (NBaP) and their derivatives, was used to determine structure-activity relationships. It was found that isomeric NBaPs are activated to DNA damaging and mutagenic derivatives by nitroreduction, ring-oxidation, or by a combination of these two pathways. A general finding was that NBaPs and derivatives with their nitro substituent oriented perpendicular to the aromatic system exhibit either very weak or no direct-acting mutagenicity in S. typhimurium strains TA98 and TA100. In this paper, we also discuss the effect of the location of the nitro group on the metabolism and the mutagenicity of NBaPs and the effect of oxygen-containing functional groups on the mutagenicity of NBaP derivatives. These findings provide a useful molecular basis for interpreting and predicting the direct-acting mutagenicity of nitro-PAHs.
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Zhang PC, Bai C, Ho PK, Dai Y, Wu YS. Observing interactions between the IgG antigen and anti-IgG antibody with AFM. IEEE ENGINEERING IN MEDICINE AND BIOLOGY MAGAZINE : THE QUARTERLY MAGAZINE OF THE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY 1997; 16:42-6. [PMID: 9086371 DOI: 10.1109/51.582175] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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72
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Huang SL, Luo X, Wu YS. [Clinical application of modified proportional unit of middle finger to determine the depth for intra-esophageal atrial pacing to stop supraventricular tachycardia]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1997; 17:68-9. [PMID: 9812657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVE To determine the location for catheter electrode of intra-esophageal atrial pacing. METHODS The catheter load was placed at a length eleven times that of the modified proportional unit of middle finger for intra-esophageal atrial pacing to stop the supraventricular tachycardia of 21 patients. RESULTS Ninteen of them showed remarkable effect and 2 were effective. Tachycardia of all the patients was stopped, symptoms and signs such as chest distress, palpitation relieved and the blood pressure normalized. CONCLUSION This is an accurate localization, rapid, convenient method with remarkable effects, it is a new way in rescuing supraventricular tachycardia patients.
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73
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Su WP, Wu YS, Yang J. Mutual Exclusion Statistics between Quasiparticles in the Fractional Quantum Hall Effect. PHYSICAL REVIEW LETTERS 1996; 77:3423-3426. [PMID: 10062216 DOI: 10.1103/physrevlett.77.3423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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74
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Hatsugai Y, Kohmoto M, Wu YS. Hidden massive Dirac fermions in effective field theory for integral quantum Hall transitions. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:4898-4906. [PMID: 9986451 DOI: 10.1103/physrevb.54.4898] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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75
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Hatsugai Y, Kohmoto M, Koma T, Wu YS. Mutual-exclusion statistics in exactly solvable models in one and higher dimensions at low temperatures. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:5358-5367. [PMID: 9986495 DOI: 10.1103/physrevb.54.5358] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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76
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Hatsugai Y, Kohmoto M, Wu YS. Quantum group, Bethe ansatz equations, and Bloch wave functions in magnetic fields. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:9697-9712. [PMID: 9982526 DOI: 10.1103/physrevb.53.9697] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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77
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Wu YS, Yu Y. Bosonization of one-dimensional exclusons and characterization of Luttinger liquids. PHYSICAL REVIEW LETTERS 1995; 75:890-893. [PMID: 10060144 DOI: 10.1103/physrevlett.75.890] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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78
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Wu YS, Bevilacqua VL, Berg JM. Fibrillin domain folding and calcium binding: significance to Marfan syndrome. CHEMISTRY & BIOLOGY 1995; 2:91-7. [PMID: 9383409 DOI: 10.1016/1074-5521(95)90281-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Marfan syndrome is a heritable disorder of connective tissue which has been associated with mutations in a gene encoding fibrillin, a 350 kD glycoprotein found in microfibrils. This protein consists of approximately 60 domains, 47 of which have similarity to epidermal growth factor (EGF). The first mutations to be detected were found in two sporadic cases that had identical Arg to Pro changes within one EGF-like domain. Based on sequence features common to 43 of the EGF-like domains, it was proposed that these domains might bind calcium. Through the synthesis and characterization of wild-type and mutated single domain peptides, we examined the structural and calcium-binding properties of an isolated EGF-like domain from fibrillin and the effects of the Arg to Pro sequence change. RESULTS A peptide corresponding to the thirteenth putative calcium-binding, EGF-like domain of fibrillin (the site of the first detected mutations) was synthesized. This peptide could be easily oxidized and refolded. The structure of this domain was probed using NMR methods, indicating features characteristic of the known structures of EGF-like domains. The domain bound to calcium with moderate affinity (Kd = 0.6 +/- 0.1 mM) with no major changes in structure induced upon calcium binding. A synthetic peptide containing the Arg to Pro mutation was found to be drastically impaired in its ability to fold in vitro. CONCLUSIONS As predicted, a fibrillin domain forms a calcium-binding, EGF-like module. As the putative calcium-binding sites are found at the amino-terminal end of the modules, we propose that calcium ions may bind in the interfaces between domains, affecting the overall structure of the protein. The Arg to Pro mutation blocks domain folding in vitro, suggesting that lack of proper domain folding in vivo may contribute to the molecular defects responsible for Marfan syndrome.
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Fu PP, Herreno-Saenz D, Von Tungeln LS, Lay JO, Wu YS, Lai JS, Evans FE. DNA adducts and carcinogenicity of nitro-polycyclic aromatic hydrocarbons. ENVIRONMENTAL HEALTH PERSPECTIVES 1994; 102 Suppl 6:177-83. [PMID: 7889844 PMCID: PMC1566865 DOI: 10.1289/ehp.94102s6177] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
We have been interested in the structure-activity relationships of nitro-polycyclic aromatic hydrocarbons (nitro-PAHs), and have focused on the correlation of structural and electronic features with biological activities, including mutagenicity and tumorigenicity. In our studies, we have emphasized 1-, 2-, 3-, and 6-nitrobenzo[a]pyrenes (nitro-B[a]Ps) and related compounds, all of which are derived from the potent carcinogen benzo[a]pyrene. While 1-, 2-, and 3-nitro-B[a]P are potent mutagens in Salmonella, 6-nitro-B[a]P is a weak mutagen. In vitro metabolism of 1- and 3-nitro-B[a]P has been found to generate multiple pathways for mutagenic activation. The formation of the corresponding trans-7,8-dihydrodiols and 7,8,9,10-tetrahydrotetrols suggests that 1- and 3-nitro-B[a]P trans-7,8-diol-9,10-epoxides are ultimate metabolites of the parent nitro-B[a]Ps. We have isolated a DNA adduct from the reaction between 3-nitro-B[a]P trans-7,8-diol-anti9,10-epoxide and calf thymus DNA, and identified it as 10-(deoxyguanosin-N2-yl)-7,8,9-trihydroxy-7,8,9,10-tetrahydro-3-ni tro-B[a]P . The same adduct was identified from in vitro metabolism of [3H]3-nitro-B[a]P by rat liver microsomes in the presence of calf thymus DNA. A DNA adduct of 3-nitro-B[a]P formed from reaction of N-hydroxy-3-amino-B[a]P, prepared in situ with calf thymus DNA was also isolated. This adduct was identified as 6-(deoxyguanosin-N2-yl)-3-amino-B[a]P. The same adduct was obtained from incubating DNA with 3-nitro-B[a]P in the presence of the mammalian nitroeductase, xanthine oxidase, and hypoxanthine.(ABSTRACT TRUNCATED AT 250 WORDS)
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Hatsugai Y, Kohmoto M, Wu YS. Explicit solutions of the Bethe ansatz equations for the Bloch electrons in a magnetic field. PHYSICAL REVIEW LETTERS 1994; 73:1134-1137. [PMID: 10057633 DOI: 10.1103/physrevlett.73.1134] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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81
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Wu YS. Statistical distribution for generalized ideal gas of fractional-statistics particles. PHYSICAL REVIEW LETTERS 1994; 73:922-925. [PMID: 10057575 DOI: 10.1103/physrevlett.73.922] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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82
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Adler SL, Wu YS. Algebraic and geometric aspects of generalized quantum dynamics. Int J Clin Exp Med 1994; 49:6705-6708. [PMID: 10016994 DOI: 10.1103/physrevd.49.6705] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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83
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Chen W, Fisher MP, Wu YS. Mott transition in an anyon gas. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:13749-13761. [PMID: 10007777 DOI: 10.1103/physrevb.48.13749] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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84
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Abstract
In 30 patients with Lyme disease, the lesions of erythema chronicum migrans were absent or atypical. Thirty biopsy specimens were obtained from cutaneous lesions of these patients. The predominant histological finding was a superficial dermal and deep perivascular and interstitial infiltrate composed mostly of lymphocytes but containing a few eosinophils and plasma cells. In serial sections with a silver stain, a few Borrelia burgdorferi were found in the biopsy specimens from cutaneous lesions in five patients. Thus, there is evidence that the typical lesions of erythema chronicum migrans of the classical Lyme disease do not develop while Borrelia burgdorferi survive and persist in cutaneous lesions.
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Fu PP, Wu YS, Von Tungeln LS, Lai JS, Chiarelli MP, Evans FE. Synthesis of 3-nitrobenzo[a]pyrene bay-region trans-7,8-diol anti-9,10-epoxide and the corresponding N2-deoxyguanosine adduct. Chem Res Toxicol 1993; 6:603-8. [PMID: 8292736 DOI: 10.1021/tx00035a003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
3-Nitrobenzo[a]pyrene (3-nitro-BaP) is a potent mutagenic environmental contaminant, and its biological activities have been intensively studied. It is significant to prepare its reactive metabolites and the corresponding modified DNA adducts for biological studies. The synthesis of its oxidized proximate metabolite trans-7,8-dihydro-3-nitrobenzo[a]pyrene (3-nitro-BaP-trans-7,8-dihydrodiol, 1), its oxidized ultimate metabolite trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydro-3- nitrobenzo[a]pyrene (3-nitro-BaP-DE, 2), and the corresponding DNA adduct 10-(deoxyguanosin-N2-yl)-7,8,9-trihydroxy-7,8,9,10-tetrahydro-3- nitrobenzo[a]pyrene is described.
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86
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Wen XG, Wu YS. Transitions between the quantum Hall states and insulators induced by periodic potentials. PHYSICAL REVIEW LETTERS 1993; 70:1501-1504. [PMID: 10053308 DOI: 10.1103/physrevlett.70.1501] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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87
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Wu YS, Zhang FB. The treatment of tibial and fibular fractures with a rectangle-shaped intramedullary nail. CONTEMPORARY ORTHOPAEDICS 1993; 26:279-88. [PMID: 10148379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
A study is reported in which excellent results were achieved with use of a flexible rectangle-shaped intramedullary (RIM) nail in the treatment of 171 tibial and fibular shaft fractures in a series of 165 patients. Mechanical analysis showed improved fracture stability compared to fractures treated with an Ender nail. To the best of the authors' knowledge, the method of treatment described in this report has not been discussed previously in the Western literature.
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88
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Chen W, Semenoff GW, Wu YS. Two-loop analysis of non-Abelian Chern-Simons theory. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1992; 46:5521-5539. [PMID: 10014944 DOI: 10.1103/physrevd.46.5521] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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89
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Onigbinde TA, Wu AH, Wu YS, Simmons MJ, Wong SS. Mechanism of differential inhibition of lactate dehydrogenase isoenzymes in the BMC LD-1 assay. Clin Biochem 1992; 25:425-9. [PMID: 1477966 DOI: 10.1016/0009-9120(92)90045-t] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The mechanism of inhibition of lactate dehydrogenase (LD) isoenzymes by guanidinium thiocyanate (GSCN) used in the LD-1 assay developed by Boehringer Mannheim Corporation (BMC) was investigated. Michaelis-Menten inhibition kinetics for the individual isoenzymes revealed that GSCN competitively inhibited LD-1 in the presence of lactate and NAD+, but is a noncompetitive inhibitor of LD-5. LD-2 and LD-3 exhibited mixed inhibition kinetics. The inhibition constants were two- to threefold smaller for LD-5 than for LD-1. Time-dependent studies also showed that the isoenzymes underwent a different rate of inactivation by GSCN. LD-5, LD-3, and LD-2 were rapidly inactivated within 1 min under the BMC assay conditions, whereas LD-1 lost only about 20% of activity after 10 min. The presence of lactate further protects LD-1, but not other isoenzymes. Under this condition, LD-1 was not inactivated during the initial 6 min of reaction. Separate experiments demonstrated that both guanidinium and thiocyanate ions are responsible for the inactivation process that was found to be irreversible. We speculate that GSCN selectively denatures the M subunit of LD. The H subunit is less susceptible to denaturation and is further stabilized by lactate.
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Yung CH, Chow MP, Hu HY, Tzeng JL, Wu YS, Lyou JY, Liu WT. Evaluation of anti-HTLV-1 in physical-checkup individuals and blood donors in Taiwan. ZHONGHUA MINGUO WEI SHENG WU JI MIAN YI XUE ZA ZHI = CHINESE JOURNAL OF MICROBIOLOGY AND IMMUNOLOGY 1992; 25:244-51. [PMID: 1342641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The gelatin particle agglutination (GPA) test specific for antibody detection of human T-cell lymphotropic virus type 1 (HTLV-1) was used to screen 500 blood donors and 5000 physical-checkup individuals at Veterans General Hospital-Taipei. The positive rate of physical-checkup individuals and the blood donors was 0.18% (9/5000) and 0% (0/5000) respectively. Among the 9 GPA positive specimens, eight were confirmed to be positive by western blot analysis and a prevalence rate of 0.16% (8/5000). Seven of the nine GPA positive samples were also positive by indirect fluorescent antibody test and two of them had indeterminate results. Since GPA is less expensive, relatively simple and convenient, we recommend that GPA could be used as screening test for HTLV-1 infection of blood donors, followed by western blot method as a confirmatory test in blood bank.
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Chen W, Wu YS. Erratum: Implications of a cosmological constant varying as R-2. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1992; 45:4728. [PMID: 10014388 DOI: 10.1103/physrevd.45.4728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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92
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Kohmoto M, Halperin BI, Wu YS. Diophantine equation for the three-dimensional quantum Hall effect. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:13488-13493. [PMID: 10001436 DOI: 10.1103/physrevb.45.13488] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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93
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Yu F, Wu YS. Nonlinear W-circumflex. PHYSICAL REVIEW LETTERS 1992; 68:2996-2999. [PMID: 10045581 DOI: 10.1103/physrevlett.68.2996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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94
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Hatsugai Y, Kohmoto M, Wu YS. Multisheet configuration space and fractional quantum statistics. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:11161-11165. [PMID: 10001038 DOI: 10.1103/physrevb.45.11161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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95
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Brack JT, Feltham A, Johnson RR, Jones G, Kermani MA, Meirav O, Pavan M, Sevior ME, Sossi V, Vetterli D, Weber P, Smith GR, Amaudruz PA, Healey D, Ottewell DF, Wu YS, Chen XY, Hoibråten S, Kohler MD, Kraushaar JJ, Ristinen RA, Smythe WR, Mathie EL, Yeomans DM, Schubank R, Stevenson NR, Gibson EF. Analyzing powers for pi +/--13C. PHYSICAL REVIEW. C, NUCLEAR PHYSICS 1992; 45:698-704. [PMID: 9967805 DOI: 10.1103/physrevc.45.698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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96
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Cayanis E, Russo JJ, Wu YS, Edelman IS. Serum independence of low K+ induction of Na,K-ATPase: possible role of c-fos. J Membr Biol 1992; 125:163-70. [PMID: 1313115 DOI: 10.1007/bf00233355] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cultured ARL15 cells respond to abnormally low extracellular K+ concentrations by increasing the abundance of Na,K-ATPase (the Na/K pump). This response is preceded by significant increases in the mRNAs of the alpha 1 and beta 1 subunits of this enzyme, implying transcriptional or post-transcriptional regulation in the response. The present study concerned the possible participation of serum factors in low K+ induction of Na,K-ATPase. In normal K+ (4.5 mM) or low K+ (0.68 mM) the presence of 10% calf serum had no effect on Na,K-ATPase activity. The serum independence of the response to low K+ raised the possibility that low K+ may itself elicit a "growth" response. Accordingly, the effect of low K+ on mRNA abundances of four proto-oncogenes (c-fos, c-myc, c-jun and c-ski) was evaluated in the early phase of the response by quantitative Northern blot analysis. The mRNA for c-fos was transiently elevated by low K+, with a peak at 30 min. In contrast, low K+ had no measurable effect on the abundances of c-myc, c-jun and c-ski, for up to 2 hr of exposure. The early elevation of c-fos mRNA makes it a candidate mediator in this signal-transduction pathway. Induction of c-fos mRNA by the phorbol ester, PMA, or by dioctanoyl glycerol, however, had no effect on Na,K-ATPase activity. These results indicate that an increase in c-fos mRNA alone is not sufficient to induce Na,K-ATPase. Whether induction of c-fos is necessary for the response to low K+ remains to be determined in future studies.
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Wu YS, Becker CR, Waag A, Kraus MM, Bicknell-Tassius RN, Landwehr G. Correlation of the Cd-to-Te ratio on CdTe surfaces with the surface structure. PHYSICAL REVIEW. B, CONDENSED MATTER 1991; 44:8904-8911. [PMID: 9998849 DOI: 10.1103/physrevb.44.8904] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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98
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Chen W, Semenoff GW, Wu YS. Scale and conformal invariance in Chern-Simons-matter field theory. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1991; 44:R1625-R1628. [PMID: 10014072 DOI: 10.1103/physrevd.44.r1625] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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99
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Hatsugai Y, Kohmoto M, Wu YS. Anyons on a torus: Braid group, Aharonov-Bohm period, and numerical study. PHYSICAL REVIEW. B, CONDENSED MATTER 1991; 43:10761-10768. [PMID: 9996807 DOI: 10.1103/physrevb.43.10761] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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100
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Wu YS, Hatsugai Y, Kohmoto M. Gauge invariance of fractionally charged quasiparticles and hidden topological Zn symmetry. PHYSICAL REVIEW LETTERS 1991; 66:659-662. [PMID: 10043866 DOI: 10.1103/physrevlett.66.659] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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