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Kuang YD, Shi SQ, Chan PKL, Chen CY. The effect of intertube van der Waals interaction on the stability of pristine and functionalized carbon nanotubes under compression. NANOTECHNOLOGY 2010; 21:125704. [PMID: 20195018 DOI: 10.1088/0957-4484/21/12/125704] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This paper investigates the effect of intertube van der Waals interaction on the stability of pristine and covalently functionalized carbon nanotubes under axial compression, using molecular mechanics simulations. After regulating the number of inner layers of the armchair four-walled (5, 5)@(10, 10)@(15, 15)@(20, 20) and zigzag four-walled (6, 0)@(15, 0)@(24, 0)@(33, 0) carbon nanotubes, the critical buckling strains of the corresponding tubes are calculated. The results show that each of the three inner layers in the functionalized armchair nanotube noticeably contributes to the stability of the outermost tube, and together increase the critical strain amplitude by 155%. However, the three inner layers in the corresponding pristine nanotube, taken together, increase the critical strain of the outermost tube by only 23%. In addition, for both the pristine and functionalized zigzag nanotubes, only the (24, 0) layer, among the three inner layers, contributes to the critical strain of the corresponding outermost tube, by 11% and 29%, respectively. The underlying mechanism of the enhanced stability related to nanotube chirality and functionalization is analyzed in detail.
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Jiang XC, Chen CY, Chen WM, Yu AB. Role of citric acid in the formation of silver nanoplates through a synergistic reduction approach. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:4400-8. [PMID: 19957976 DOI: 10.1021/la903470f] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This study discusses the function of citrate ions in the synthesis of silver nanoplates through a synergetic reduction approach in ambient conditions. It was found that the citrate ions can play multiple roles in the synthesis process, including a reducing agent, a stabilizer, and a complex agent, and they show some unique features under the reported conditions. The reducing ability of these citrate ions was shown to be weaker than that of sodium borohydride and/or L-ascorbic acid used in the same system. The stability in the shape/size control of silver particles is weaker than that of other surfactants tested in the present system, such as bis(2-ethylhexyl)sulfosuccinate (AOT) and thiols. Citrate ions could form a silver complex with silver ions as [Ag(2)(+)...citrate] or [Ag(3)(C(6)H(5)O(7))(n+1)](3n-), as confirmed by electrospray ionization (ESI) mass spectrometry and the kinetic analysis that the molar ratio of citric acid or sodium citrate to silver ions can greatly influence the reaction rate and, hence, the particle growth of silver nanoparticles. Such a complexing effect is further confirmed by the use of chelating ions (e.g., [Fe(CN)(6)](4-)) to form Ag(n)[Fe(CN)(6)](n-4), which can largely influence the synthesis of silver nanoparticles. These results show some formation results of generating silver nanoplates involving citrate ions, which are useful in the shape-controlled synthesis of other metallic nanoparticles with desirable functionalities.
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Chen YC, Chang HH, Wen CJ, Lin WY, Chen CY, Hong BS, Huang KC. Elevated serum dehydroepiandrosterone sulphate level correlates with increased risk for metabolic syndrome in the elderly men. Eur J Clin Invest 2010; 40:220-5. [PMID: 20050878 DOI: 10.1111/j.1365-2362.2009.02248.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The previous studies regarding the association between endogenous dehydroepiandrosterone (DHEA) sulphate level and metabolic syndrome are inconsistent. This study aimed to investigate such relationship in elderly Taiwanese men. MATERIALS AND METHODS Five hundred and eighty-five elderly Taiwanese men (mean age 68.7 +/- 8.3 years) were enrolled as the baseline cohort population in 2000. In addition to a questionnaire, body mass index (BMI), blood pressure, fasting blood glucose, lipids, albumin and serum DHEA-S levels were measured for each participant. Metabolic syndrome was based on the definition by the America Heart Association/National Heart Lung Blood Institute. RESULTS The prevalence of metabolic syndrome was 33.3%. Using multivariate logistic regression analyses with adjustments for age, smoking, alcohol, physical activities, albumin and BMI, there was a positive relationship between serum DHEA-S level and metabolic syndrome. The highest DHEA-S quartile group had increased risk for metabolic syndrome (odds ratio = 2.68, 95% confidence interval: 1.44-5.01, P < 0.01) compared with the lowest quartile group. The mean serum DHEA-S level increased with increasing number of metabolic syndrome components. CONCLUSIONS The prevalence of metabolic syndrome increases with elevated DHEA-S levels among elderly Taiwanese men. Thus, elevated serum DHEA-S level should be treated as an important risk factor for metabolic syndrome in elderly men.
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Fu SF, Wang SM, Lee L, Chen CY, Tsai WC, Chou WC, Lee MC, Chang WH, Chen WK. The structural and optical properties of InN nanodots grown with various V/III ratios by metal-organic chemical vapor deposition. NANOTECHNOLOGY 2009; 20:295702. [PMID: 19567947 DOI: 10.1088/0957-4484/20/29/295702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Self-assembled InN nanodots have been prepared at 650 degrees C with various V/III ratios from 500 to 30 000 by metal-organic chemical vapor deposition (MOCVD). It is found that the dot density and morphological size as well as the optical properties all display drastic changes at V/III = 12 000. Generally, denser and smaller InN nanodots with higher emission energy and narrower linewidth were obtained when growth was conducted at V/III ratios slightly lower than 12 000 as compared to those at higher V/III ratios. The physical properties of our MOCVD-grown InN nanodots are sensitive to the surface structure and the morphology is very similar to molecular beam epitaxially grown GaN and InN films, which may be used as a guide to optimize the InN growth.
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Chen CY, Han F, Zhao C, Lu LX, Sun Y, Liu XF, Lu TX. Treatment results and late complications of 556 patients with locally advanced nasopharyngeal carcinoma treated with radiotherapy alone. Br J Radiol 2009; 82:452-8. [PMID: 19451314 DOI: 10.1259/bjr/72813246] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The aim of this study was to investigate the outcome in 556 patients with locally advanced nasopharyngeal carcinomas treated by radiation therapy alone. We observed 556 patients with stage T3-4 and N0-3 carcinoma who were treated by conventional radiotherapy alone between January and December 1999. The total dose delivered to the nasopharynx was 66-80 Gy over 6.5-8 weeks and to the neck lymph nodes 60-70 Gy over 6-7 weeks. The 5-year actuarial overall survival rate (OS) reached 66.41%. The OS was higher among stage T3 patients than among stage T4 patients (69.12% vs 58.96%, p = 0.0359). Among patients with stage N0, N1, N2 and N3 disease, the OS was 73.98%, 65.96%, 57.58% and 29.39%, respectively (p = 0.0009). Differences in disease-free survival, locoregional control rate and metastasis-free survival rate among each N stage were statistically significant, although this was not true of differences between stage T3 and T4 disease. Multivariate analysis showed that gender, age, T stage and N stage were significant prognostic factors for 5-year overall survival, disease-free survival, locoregional control and metastasis-free survival. We found that N stage is the dominant prognostic indicator for patients with locally advanced nasopharyngeal carcinoma receiving conventional radiation therapy alone, and that T stage was only a secondary correlative factor.
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Ko Y, Liu CW, Chen CY, Maruthasalam S, Lin CH. First Report of Stem-End Rot of Mango Caused by Phomopsis mangiferae in Taiwan. PLANT DISEASE 2009; 93:764. [PMID: 30764368 DOI: 10.1094/pdis-93-7-0764a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Mango (Mangifera indica L.) is grown on approximately 20,000 ha in Taiwan. It is an economically important crop and the income of many fruit farmers comes primarily from mango production. During 2006 and 2007, a stem-end rot disease was observed 1 week after harvest on 28 to 36% of stored mangoes picked from six orchards in the Pingtung, Tainan, and Kaoshiung regions. Two popular mango cultivars, Keitt and Irwin, showed greater susceptibility to this disease, while 'Haden' was found to be moderately susceptible. In storage, symptoms initially appeared as light-to-dark brown lesions surrounding peduncles. Rot symptoms advanced slowly but eventually penetrated the mesocarp, which consequently reduced the commercial value of fruits. The fungus formed abundant pycnidia (0.1 to 0.6 mm in diameter) on infected fruits in advanced stages of symptom development. Pieces of symptomatic fruits plated on acidified potato dextrose agar (PDA) and incubated at 25 ± 1°C consistently yielded the same fungus. A single conidial isolate was cultured. Pycnidia developed on PDA after continuous exposure to light for 9 to 14 days. On the basis of morphological characteristics, the fungus was identified as Phomopsis mangiferae L. (2,3). Pycnidia released two types of conidia: α-conidia (5 to 10 × 2.3 to 4.0 μm) were hyaline and oval to fusoid; and β-conidia (15.0 to 37.5 × 1.3 to 2.5 μm) were hyaline and filiform with characteristic curves. Conidiophores were hyaline, filiform, simple or branched, septate, and 15 to 75 μm long. Cultures incubated under continuous fluorescent light (185 ± 35 μE·m-2·s-1) at 25°C for 3 days were used as inoculum for pathogenicity tests. Five fruits from 'Keitt' were wounded with a sterilized scalpel and each wound (2 × 2 × 2 mm) was inoculated with either a 5-mm mycelium agar plug or a 0.5-ml spore suspension (105 conidia per ml) of the fungus. Five wounded fruits inoculated with 5-mm PDA plugs or sterile water alone served as controls. Inoculated areas were covered with moist, sterile cotton. Fruits were enclosed in plastic bags and incubated at 24°C for 3 days. The test was performed three times. The same symptoms were observed on all inoculated fruits, whereas no decay was observed on control fruits. Reisolations from the inoculated fruits consistently yielded P. mangiferae, thus fulfilling Koch's postulates. This disease has previously been reported in Australia, Brazil, China, Cuba, India, Malaysia, and the United States (1). To our knowledge, this is the first report of P. mangiferae causing stem-end rot disease on mangoes in Taiwan. Our report necessitates taking preventive strategies in the field, prior to or after harvest, to contain postharvest losses in mangoes. References: (1) G. I. Johnson. Page 39 in: Compendium of Tropical Fruit Diseases. R. C. Ploetz et al., eds. The American Phytopathological Society. St. Paul, MN, 1994. (2) R. C. Ploetz, ed. Page 354 in: Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, UK, 2003. (3) E. Punithalingam. No. 1168 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1993.
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Chuang JY, Yang SS, Lu YT, Hsieh YY, Chen CY, Chang SC, Chang CS, Yeh HZ, Kao JH. IL-10 promoter gene polymorphisms and sustained response to combination therapy in Taiwanese chronic hepatitis C patients. Dig Liver Dis 2009; 41:424-30. [PMID: 19004675 DOI: 10.1016/j.dld.2008.09.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 08/14/2008] [Accepted: 09/09/2008] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Host genetic factors may affect clinical outcomes of hepatitis C virus (HCV) infection; however, the possible mechanisms remain largely unknown. The role of immunopathogenesis in chronic hepatitis C leads to extensive exploration of host immunity including inflammatory cytokines. METHODS We examined interleukin 10 (IL-10) promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site and studied their association with response to 24 weeks of pegylated interferon plus ribavirin treatment in 143 chronic hepatitis C patients, of whom 97 (67.8%) achieved a sustained virologic response (SVR). In addition, 134 healthy adults were used as controls. RESULTS Of chronic hepatitis C patients, 111 (77.6%) were genotype 1 infection, 32 (22.4%) were genotype 2 infection. Patients with sustained virologic response were younger and had higher pretreatment ALT levels than those without. No statistical difference was found between chronic hepatitis C patients who achieved SVR or not in terms of gender, HCV genotype, pretreatment HCV RNA levels, and severity of liver disease. The serum IL-10 levels were comparable between healthy controls and chronic hepatitis C patients as well as between HCV patients with and without SVR. The distribution of IL-10 promoter gene polymorphisms at positions -1082, -819, and -592 relative to transcription start site was comparable between HCV patients and healthy controls as well as HCV patients with and without SVR. A high frequency of ATA haplotype of common IL-10 promoter gene SNPs was found in both chronic hepatitis C patients (70.3%) and healthy controls (69.8%). However, ATA haplotype was not associated with SVR in chronic hepatitis C patients. CONCLUSIONS Our data fail to demonstrate the influence of IL-10 promoter gene polymorphisms on the response to combination therapy in Taiwanese chronic hepatitis C patients. The impact of genetic variations in IL-10 haplotype on the response to anti-HCV treatment among different ethnic populations deserves further examination.
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He XQ, Kuang YD, Chen CY, Li GQ. Enhanced mechanical properties of single-walled carbon nanotubes due to chemical functionalization. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:215301. [PMID: 21825544 DOI: 10.1088/0953-8984/21/21/215301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Recent studies have shown that the chemical functionalization of carbon nanotubes weakens most of their mechanical properties such as the critical buckling force under compression and the critical buckling moment under torsion. However, the mechanical properties including the critical bending curvature and the critical bending moment of single-walled carbon nanotubes can be improved after functionalization as shown in this paper. The molecular mechanics simulations reveal that there exists an optimum functionalization degree at which the critical curvatures of the functionalized carbon nanotubes reaches its maximum value. The critical curvatures of the carbon nanotubes increase with increasing functionalization degree below the optimum value, while the critical curvatures change little as the functionalization degree is beyond the optimum value. The influences of the bending directions and the aspect ratios of the functionalized carbon nanotubes are also examined via molecular mechanics simulations.
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Chen CY, Lin CA, Chen MJ, Lin GR, He JH. ZnO/Al2O3 core-shell nanorod arrays: growth, structural characterization, and luminescent properties. NANOTECHNOLOGY 2009; 20:185605. [PMID: 19420621 DOI: 10.1088/0957-4484/20/18/185605] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report an aqueous chemical method to fabricate well-aligned ZnO/Al(2)O(3) nanocrystal (NC) core-shell nanorod arrays (NRAs). Structural characterization showed that the shell layers are composed of alpha-Al(2)O(3) nanocrystals. Photoluminescence measurements showed the enhancement of near-band-edge (NBE) emission of ZnO NRAs due to the presence of Al(2)O(3) NC shells. The Al(2)O(3) NC shell layer resulting in the flat-band effect near the ZnO surface leads to a stronger overlap of the wavefunctions of electrons and holes in the ZnO core, further enhancing the NBE emission. This approach should be very useful in designing many other core-shell NRAs for creating varieties of high-efficiency optoelectronic devices.
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He JH, Chang PH, Chen CY, Tsai KT. Electrical and optoelectronic characterization of a ZnO nanowire contacted by focused-ion-beam-deposited Pt. NANOTECHNOLOGY 2009; 20:135701. [PMID: 19420510 DOI: 10.1088/0957-4484/20/13/135701] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We report on the transport properties of a single ZnO nanowire (NW) measured as a function of the length/square of the radius ratio via the transmission line method (TLM). The specific contact resistance of FIB-Pt contacts to the ZnO NWs is determined to be as low as 1.1 x 10(-5) Omega cm(2). The resistivity of the ZnO NWs is measured to be 2.2 x 10(-2) Omega cm. ZnO NW-based UV photodetectors contacted by FIB-Pt with a photoconductive gain as high as approximately 10(8) have been fabricated and characterized.
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He JH, Ho CH, Chen CY. Polymer functionalized ZnO nanobelts as oxygen sensors with a significant response enhancement. NANOTECHNOLOGY 2009; 20:065503. [PMID: 19417388 DOI: 10.1088/0957-4484/20/6/065503] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A plasma-polymerized acrylonitrile (PP-AN)/ZnO nanobelt (NB) nanosensor reveals a better oxygen-sensing response than a bare ZnO NB nanosensor due to the sorption nature of the polymer. With the aid of UV light, significant response enhancements of PP-AN/ZnO NB nanosensors at low temperature have been observed since the effects of oxygen desorption/adsorption in PP-AN on the electron depletion region in the ZnO are significant. The minimum sensitivity at 150 degrees C is 16.6 ppm. This work permits its feasibility in areas where it is impossible to work at higher temperatures since lowering the working temperature of the sensor can avoid the structural deterioration, causing instability in the response.
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Silver MR, Geronemus R, Krause M, Chen CY, Kewalramani R, Stehman-Breen C. Anemia treatment with Q2W darbepoetin alfa in patients with chronic kidney disease naïve to erythropoiesis-stimulating agents. Curr Med Res Opin 2009; 25:123-31. [PMID: 19210145 PMCID: PMC3133722 DOI: 10.1185/03007990802594818] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To evaluate the efficacy and safety of darbepoetin alfa dosed every-other-week (Q2W) to treat anemia in subjects with chronic kidney disease (CKD), not receiving dialysis, who were naïve to erythropoiesis-stimulating agent (ESA) therapy. RESEARCH DESIGN AND METHODS This was an open-label, multicenter, single-arm study enrolling ESA-naïve CKD subjects with baseline hemoglobin (Hb) < 11.0 g/dL. Q2W darbepoetin alfa treatment was initiated at a dose of 0.75 microg/kg and titrated to achieve and maintain Hb levels at 11.0-13.0 g/dL. Treatment was administered from week 1 to week 19. MAIN OUTCOME MEASURES The primary endpoint was the proportion of subjects who achieved Hb > or = 11 g/dL at any study visit, except in week 1. Hb levels, darbepoetin alfa dose, and safety were also assessed. RESULTS Of the 128 subjects who received at least one dose of darbepoetin alfa and of the subjects who completed the study, 118 (92%) and 112 (97%), respectively, achieved a Hb > or = 11 g/dL in a median time of 5 weeks. Median darbepoetin alfa dose at week 1 and at the time of achieving a Hb > or = 11 g/dL were 60 and 80 microg, respectively. Darbepoetin alfa was well-tolerated, and short-term adverse events were consistent with those expected in CKD subjects. CONCLUSIONS This study demonstrates that de novo Q2W darbepoetin alfa was effective in correcting and maintaining Hb levels in ESA-naïve subjects with CKD who were not receiving dialysis. Study limitations, including lack of a control arm for the study and multiple race information for subjects, must be considered in interpreting the results. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov, NCT00112008.
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Chen CY, He T, Mao XL, Friis TE, Qin RH, Jian YT. A novel xylene substitute for histotechnology and histochemistry. Biotech Histochem 2009. [DOI: 10.1080/10520290903235445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Li CC, Chen CY, Chen CJ. Computed tomographic diagnosis of midgut volvulus in an adult. Acta Clin Belg 2009; 64:68-9. [PMID: 19317245 DOI: 10.1179/acb.2009.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Chen WD, Xiao J, Shen Y, Fu YQ, Meng FC, Chen CY, Zou Y, Hutton R. High precision high voltage divider and its application to electron beam ion traps. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:123304. [PMID: 19123559 DOI: 10.1063/1.3053449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A high precision high voltage divider has been developed for the electron beam ion trap in Shanghai. The uncertainty caused by the temperature coefficient of resistance (TCR) and the voltage coefficient of resistance has been studied in detail and was minimized to the level of ppm (10(-6)) range. Once the TCR was matched between the resistors, the precision of the dividing ratio finally reached the ppm range also. We measured the delay of the divider caused by the capacitor introduced to minimize voltage ripple to be 2.35 ms. Finally we applied the divider to an experiment to measure resonant energies for some dielectronic recombination processes for highly charged xenon ions. The final energies include corrections for both space charge and fringe field effects are mostly under 0.03%.
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Chen CY, Hathaway KM, Thompson DG, Folt CL. Multiple stressor effects of herbicide, pH, and food on wetland zooplankton and a larval amphibian. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2008; 71:209-18. [PMID: 17904219 PMCID: PMC3097124 DOI: 10.1016/j.ecoenv.2007.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 05/25/2007] [Accepted: 08/01/2007] [Indexed: 05/17/2023]
Abstract
Interactions of herbicides and natural environmental stressors such as pH and food availability are poorly understood. We tested a chemical formulation of triclopyr (Release) at environmentally relevant test concentrations (0.25 and 0.50 mg L(-1)) in combination with two levels of pH (pH 5.5 and 7.5), and two levels of food availability (high and low). Population level effects of each stressor alone and in combination with the others were investigated using Simocephalus vetulus, a zooplankton species, and Rana pipiens tadpoles (Gosner stage 25), both common to forest ponds and wetlands. Herbicide treatments resulted in significant decreases in survival of both test species as well as reproduction and development time for S. vetulus at levels 5-10x below predicted worst case environmental concentrations (2.6 mg L(-1)). This laboratory study demonstrates a probable risk of toxic effects of Release herbicide which may be significantly increased by low food availability and by low pH at environmentally relevant concentrations.
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Chen CY, Chien EJ, Chang FY, Lu CL, Luo JC, Lee SD. Impacts of peripheral obestatin on colonic motility and secretion in conscious fed rats. Peptides 2008; 29:1603-8. [PMID: 18565623 DOI: 10.1016/j.peptides.2008.05.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 05/03/2008] [Accepted: 05/07/2008] [Indexed: 12/14/2022]
Abstract
Obestatin, a novel putative 23-amino acid peptide, was found to be derived from a mammalian preproghrelin gene by using a bioinformatics approach. Although the effects of obestatin on food intake and upper gut motility remain controversial, no studies have been carried out to explore its influence on lower gut motility and secretion. We investigated the impacts of intravenous (IV) injection of obestatin on rat colonic motor and secretory functions. Colonic transit time, fecal pellet output, and fecal content were measured in freely fed, conscious rats, which were chronically implanted with IV and colonic catheters. To test the validity of this animal model, human/rat corticotropin-releasing factor (h/rCRF) served as a stimulatory inducer of colonic motility and secretion. IV injection of obestatin (45, 100, and 300 nmol/kg) did not affect the colonic transit time, whereas IV injection of h/rCRF (30 nmol/kg) effectively accelerated colonic transit time. IV obestatin, in every dose we tested, also did not modify fecal pellet output, frequency of watery diarrhea, total fecal weight, fecal dried solid weight, or fecal fluid weight in the first hour after injection. On the other hand, IV injection of h/rCRF significantly enhanced fecal pellet output, as well as increased the frequency of watery diarrhea, total fecal weight, fecal dried solid weight, and fecal fluid weight during the first hour after injection compared with IV saline controls. In conclusion, peripheral obestatin administration has no impact on colonic motility and secretion in conscious fed rats.
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Lai PH, Weng HH, Chen CY, Hsu SS, Ding S, Ko CW, Fu JH, Liang HL, Chen KH. In vivo differentiation of aerobic brain abscesses and necrotic glioblastomas multiforme using proton MR spectroscopic imaging. AJNR Am J Neuroradiol 2008; 29:1511-8. [PMID: 18499784 PMCID: PMC8119023 DOI: 10.3174/ajnr.a1130] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND AND PURPOSE Abscesses caused by aerobic bacteria (aerobic abscesses) can simulate intracranial glioblastomas multiforme (GBMs) in MR imaging appearance and single voxel (SV) proton MR spectroscopy of the central cavity. The purpose of our study was to determine whether MR spectroscopic imaging (SI) can be used to differentiate aerobic abscesses from GBMs. Our hypothesis was that metabolite levels of choline (Cho) are decreased in the ring-enhancing portion of abscesses compared with GBMs. MATERIALS AND METHODS Fifteen patients with aerobic abscesses were studied on a 1.5T MR scanner using an SV method and an SI method. Proton MR spectra of 15 GBMs with similar conventional MR imaging appearances were used for comparison. The resonance peaks in the cavity, including lactate, cytosolic amino acids, acetate, succinate, and lipids, were analyzed by both SV MR spectroscopy and MRSI. In the contrast-enhancing rim of each lesion, peak areas of N-acetylaspartate (NAA), choline (Cho), lipid and lactate (LL), and creatine (Cr) were measured by MRSI. The peak areas of NAA-n, Cho-n, and Cr-n in the corresponding contralateral normal-appearing (-n) brain were also measured. Maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios in abscesses and GBMs were compared using the Wilcoxon rank sum test. After receiver operating characteristic curve analysis, diagnostic accuracy was compared. RESULTS Cytosolic amino acid peaks were found in the cavity in 7 of 15 patients with aerobic abscesses. Means and SDs of maximum Cho/Cr, Cho/NAA, LL/Cr-n, and Cho/Cho-n and minimum Cr/Cr-n and NAA/NAA-n ratios were 3.38 +/- 1.09, 3.88 +/- 2.13, 2.72 +/- 1.45, 1.98 +/- 0.53, 0.53 +/- 0.16, and 0.44 +/- 0.09, respectively, in the GBMs, and 1.77 +/- 0.49, 1.48 +/- 0.51, 2.11 +/- 0.67, 0.81 +/- 0.21, 0.48 +/- 0.2, and 0.5 +/- 0.15, respectively, in the abscesses. Significant differences were found in the maximum Cho/Cr (P = .001), Cho/NAA (P = .006), and Cho/Cho-n ratios (P < .001) between abscesses and GBMs. Diagnostic accuracy was higher by Cho/Cho-n ratio than Cho/Cr and Cho/NAA ratios (93.3% versus 86.7% and 76.7%). CONCLUSION Metabolite ratios and maximum Cho/Cho-n, Cho/Cr, and Cho/NAA ratios of the contrast-enhancing rim were significantly different and useful in differentiating aerobic abscesses from GBMs by MRSI.
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Hsu NY, Yeh KT, Chiang IP, Pai LY, Chen CY, Ho HC. Cortactin overexpression in the esophageal squamous cell carcinoma and its involvement in the carcinogenesis. Dis Esophagus 2008; 21:402-8. [PMID: 19125793 DOI: 10.1111/j.1442-2050.2007.00775.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The aim of this study is to examine whether dysregulated expression of cortactin occurs in esophageal squamous cell carcinoma (ESCC) and is involved in the development of ESCCs. An immunohistochemistry study for cortactin expression was performed on 46 pairs of surgically resected non-tumor and ESCC tumor tissues and murine tumors of esophagi induced by a carcinogen. The results show increased cortactin expression in 20 and in 22 to a lesser extent, out of a total 46 ESCC tumor tissues. Increased cortactin was also detected in the premalignant lesions, the early stage dysplasia and carcinoma in situ, of ESCC tumor tissues. Differential polymerase chain reaction results showed slight increases in the EMS1 gene only in two of 10 ESCC tumor tissues, suggesting that EMS1 gene amplification is not the only mechanism for cortactin overexpression. In the mouse model induced by treatment with 4-nitroquinoline 1-oxide and arecoline, increased cortactin was detected in the epithelia with hyperkeratosis, papillomas, and ESCCs with invasion into the submucosa, respectively. Overall, we observed cortactin overexpression in early and late stages of human ESCCs and carcinogen-induced murine ESCCs, suggesting a role for cortactin in esophageal carcinogenesis.
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Ko Y, Chen CY, Yao KS, Liu CW, Maruthasalam S, Lin CH. First Report of Fruit Rot of Strawberry Caused by an Alternaria sp. in Taiwan. PLANT DISEASE 2008; 92:1248. [PMID: 30769472 DOI: 10.1094/pdis-92-8-1248b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In March 2005, a fruit rot disease was found in several commercial strawberry (Fragaria × ananassa Duchesne) fields at Fongyuan, 24.25°N, 120.72°E, in Taichung County in central Taiwan. The disease was rare and was negligible in most cultivated areas. However, disease incidence has increased by 4 to 5% over the last 2 years and causes significant postharvest losses. In storage, symptoms on berries include light brown-to-black, sunken, irregularly shaped lesions. The lesions gradually enlarge and become firm with a dark green-to-black, velvety surface composed of mycelia, conidiophores, and conidia. Twelve single conidial isolates (AF-1 to AF-12) of a fungus were isolated by placing portions of symptomatic fruit from four locations onto acidified potato dextrose agar (PDA) and incubating at 24 ± 1°C. One isolate from each of the four locations, AF-2, 6, 9, and 12, was selected for identification and pathogenicity studies. The fungus was identified as an Alternaria sp. according to the morphological descriptions of A. tenuissima (2,3). Conidiophores were simple or branched, straight or flexuous, septate, pale to light brown, 3.0 to 5.0 μm in diameter, and bore two to six conidia in a chain. Conidia were dark brown, obclavate or oval, and multicellular with seven transverse (in most cases) and numerous longitudinal septa. Conidia were 15.5 to 56.5 μm (average 35.0 μm) long × 6.0 to 15.0 μm (average 11.0 μm) wide at the broadest point. The pathogen was consistently isolated from berries in the field or in storage. Pathogenicity tests were conducted by inoculating 12 surface-sterilized berries with each of the four isolates. Approximately 300 μl of a spore suspension (2 × 105 conidia per ml) was placed at two points on the uninjured surface of each fruit and allowed to dry for 5 min. Control fruits were treated with sterile water. The berries were then enclosed in a plastic bag and incubated at 24 ± 1°C for 2 days. Disease symptoms similar to those described above were observed on 95% of inoculated berries 3 days after inoculation, while no symptoms developed in control berries. Reisolation from the inoculated berries consistently yielded the Alternaria sp. described above. Pathogenicity tests were performed three times. Previously, strawberry fruit rot caused by A. tenuissima was reported from Florida (2) and Malaysia (1), however, to our knowledge, this is the first report of fruit rot of strawberry caused by a species of Alternaria in Taiwan. References: (1) W. D. Cho et al. List of Plant Diseases in Korea. Korean Society of Plant Pathology, 2004. (2) C. M. Howard and E. E. Albregts. Phytopathology 63:938, 1973. (3) R. D. Milholland. Phytopathology 63:1395, 1973.
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Cheng SY, Hu WY, Liu WJ, Yao CA, Chen CY, Chiu TY. Good death study of elderly patients with terminal cancer in Taiwan. Palliat Med 2008; 22:626-32. [PMID: 18612028 DOI: 10.1177/0269216307087142] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES Over half of all terminal cancer patients in Taiwan are 65 or older, thus demonstrating the importance of terminal care for elderly people. This study investigates the good death status of elderly patients with terminal cancer, comparing the differences in the degree of good death among elderly and younger groups, and exploring the factors related to the good death score. METHODS Three hundred and sixty-six patients with terminal cancer admitted to a palliative care unit were enrolled. Two structured measurements, the good death scale and the audit scale for good death services, were used as the instruments in the study. RESULTS The scores of individual items and of the good death scale were increased significantly in both elderly (n = 206, 56.3%) and younger (n = 160, 43.7%) groups from the time of admission to just prior to death. However, the elderly group had significantly lower scores in 'awareness' (t = -3.76, P < 0.001), 'propriety' (t = -2.92, P < 0.01) and 'timeliness' (t = -2.91, P < 0.01) than the younger group prior to death. Furthermore, because of a lack of truth-telling, the elderly group also had significantly lower scores than the younger group in both 'respect for autonomy' and 'decision-making participation' (t = -2.17, P < 0.05; t = -2.21, P < 0.05, respectively). Multiple regression analysis revealed that 'respect for autonomy' (OR = 1.22, 95% CI = 0.76-1.67) and 'verbal support '(OR = 0.93, 95% CI = 0.34-1.51) were two independent correlates of the good death score in the elderly group. CONCLUSION The dilemma of truth-telling compromises the autonomy of the elderly patients with terminal cancer and consequently affects their good death scores. The palliative care team should emphasize the issue of truth-telling in the process of caring for terminally ill cancer patients, especially elderly patients.
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Liou SW, Chen CY, Yang TT, Lin JM. Determination of particulate-bound formaldehyde from burning incense by solid phase microextraction. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2008; 80:324-328. [PMID: 18344073 DOI: 10.1007/s00128-008-9381-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Accepted: 02/25/2008] [Indexed: 05/26/2023]
Abstract
This work studied the feasibility of using a solid phase microextraction (SPME) fiber for sampling and analysis of gaseous formaldehyde as well as particulate-bound formaldehyde from burning Chinese incense. The SPME fiber with PDMS/DVB coating were partially coated with o-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine hydrochloride (PFBHA), and used for sampling formaldehyde. The sampling rate for formaldehyde and its dependence on temperature, relative humidity and sampling time were observed. The same PFBHA treated fibers were, in parallel, exposed to incense burning smoke with pre-filtration and without pre- filtration for 0.5-1 min. The NIOSH method 2541 using an XAD-2 tube at a flow rate of 0.1 Lpm was also applied for sampling simultaneously. The results demonstrate that commercially available PDMS/DVB fibers partially coated with PFBHA are capable of sampling the gas phase of formaldehyde as well as particulate-bound formaldehyde. The determined level of formaldehyde was close to the result obtained by the NIOSH method 2541. However, a reduction of the fiber's formaldehyde loading capacity in the aerosol sampling in comparison with gas sampling was noticed. This indicates that the particulate characteristics, and their bound chemicals other than formaldehyde may influence the maximum loading capacity of formaldehyde, and some characteristic particulates in high concentrations may even deteriorate the fiber coating.
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Chen CY, Kao CM, Chen SC. Application of Klebsiella oxytoca immobilized cells on the treatment of cyanide wastewater. CHEMOSPHERE 2008; 71:133-139. [PMID: 18082868 DOI: 10.1016/j.chemosphere.2007.10.058] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 10/29/2007] [Accepted: 10/29/2007] [Indexed: 05/25/2023]
Abstract
Klebsiella oxytoca, isolated from cyanide-containing industrial wastewater, has been shown to be able to biodegrade cyanide to non-toxic end products. The technology of immobilized cells can be applied in biological treatment to enhance the efficiency and effectiveness of biodegradation. In this study, potassium cyanide was used as the target compound and both alginate and cellulose triacetate techniques were applied for the preparation of immobilized cells. Results from this study show that KCN can be utilized as the sole nitrogen source by K. oxytoca. The free suspension systems reveal that the cell viability was highly affected by initial KCN concentration and pH. Results show that immobilized cell systems could tolerate a higher level of KCN concentration and wider ranges of pH. In the batch experiments, the maximum KCN removal efficiencies using alginate and cellulose triacetate immobilized beads were 0.108 and 0.101mM h(-1) at pH 7, respectively. Results also indicate that immobilized system can support a higher biomass concentration. Complete KCN degradation was observed after the operation of four consecutive degradation experiments with the same batch of immobilized cells. This suggests that the activity of immobilized cells can be maintained and KCN can be used as the nitrogen source throughout KCN degradation experiments. The maximum KCN removal rates using alginate and cellulose triacetate immobilized beads in continuous-column system were 0.224 and 0.192mMh(-1) with initial KCN concentration of 3mM, respectively. Results indicate that the immobilized cells of K. oxytoca would be applicable to the treatment of cyanide-containing wastewaters.
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Ko Y, Yao KS, Chen CY, Liu CW, Maruthasalam S, Lin CH. First Report of Gummosis Disease of Plum (Prunus salicina) Caused by a Botryosphaeria sp. in Taiwan. PLANT DISEASE 2008; 92:483. [PMID: 30769694 DOI: 10.1094/pdis-92-3-0483a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plum (Prunus salicina Lindell) is grown on more than 3,870 ha in Taiwan. In 2004, a gummosis disease was observed on plum in the Ming Jian Region of Nantou County (120.675°E, 23.919°N), with 15% of the trees affected. Infections started on the current year's growth, primarily through lenticels, and formed small, sunken, discolored lesions. At later stages, white gum exuded from the lesions. Circular to oval, brown, necrotic areas were seen on the inner bark. Severely infected twigs showed defoliation and dieback. During the winter months, numerous black pycnidia or perithecia formed on infected twigs. Single conidial isolates of the pathogen were obtained from diseased twigs on acidified potato dextrose agar (PDA) and incubated at 25 ± 1°C for 3 days. On the basis of morphological traits, the fungus was identified as a Botryosphaeria sp. according to the CMI descriptions of Botryosphaeria ribis (3). Conidia (14.2 to 26.8 × 4.3 to 7.2 μm) were single celled, hyaline, and spindle shaped. Asci (105 to 135 × 12.5 to 15.5 μm) were hyaline, clavate, and bitunicate. Ascospores (18 to 22 × 7.0 to 8.2 μm) were hyaline and spindle shaped or fusoid. For pathogenicity tests, inoculum was prepared by culturing the fungus on PDA under continuous fluorescent light (128 ± 25 μE·m-2·s-1) at 25°C for 3 days. Two twigs on each of six trees were inoculated. Sharp incisions (3 × 3 × 3 mm) were made on healthy twigs (12 to 15 months old) with a sterilized scalpel and inoculated with either a 5-mm mycelial disc or 0.5 ml of a conidial suspension (105 conidia/ml) of the fungus. Inoculated areas were covered with moist, sterile cotton and the entire twigs were enclosed in plastic bags. Twigs inoculated with 5-mm PDA discs or sterile water alone served as controls. The symptoms described above were observed on all inoculated twigs 14 days after inoculation, whereas control twigs did not develop any disease symptoms. Reisolation from the inoculated twigs consistently yielded the Botryosphaeria sp., thus fulfilling Koch's postulates. Botryosphaeria spp. have been reported to cause stem blight of many plants in temperate and tropical regions of the world (4). In Taiwan, B. dothidea has been reported as the causal agent of gummosis disease of peach (1) and fruit ring rot of pear (2); however, to our knowledge, this is the first report of a Botryosphaeria sp. causing gummosis of plum. References: (1). Y. Ko et al. Plant Pathol. Bull. 1:70, 1992. (2) Y. Ko et al. Plant Prot. Bull. (Taiwan) 35:211, 1993. (3) E. Punithalingam and P. Holliday. No. 395 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1973. (4) W. A. Sinclair et al. Diseases of Trees and Shrubs. Cornell University Press, Ithaca, NY, 1987.
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Chen CY, Ying SH, Yao MS, Chiu WT, Chan WP. Sphenoid sinus osteoma at the sella turcica associated with empty sella: CT and MR imaging findings. AJNR Am J Neuroradiol 2008; 29:550-1. [PMID: 18184833 DOI: 10.3174/ajnr.a0935] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARY A 50-year-old woman presented with intermittent headache for the past few years. A paranasal sinus CT scan showed a diffusely calcified lesion at the roof of the sphenoid sinus and sella turcica, with the sellar floor bony cortex involved. Empty sella was noted. MR imaging revealed a soft-tissue lesion with low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and heterogeneous enhancement on postgadolinium images. Histologic examination revealed an osteoma composed of mature lamellar bone.
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