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Yang SY, Wang WC, Lan CB, Chen CH, Chieh JJ, Horng HE, Hong CY, Yang HC, Tsai CP, Yang CY, Cheng IC, Chung WC. Magnetically enhanced high-specificity virus detection using bio-activated magnetic nanoparticles with antibodies as labeling markers. J Virol Methods 2009; 164:14-8. [PMID: 19944721 DOI: 10.1016/j.jviromet.2009.11.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2009] [Revised: 11/05/2009] [Accepted: 11/10/2009] [Indexed: 10/20/2022]
Abstract
This study describes magnetically driven suppression of cross-reactions among molecules. First, the magnetic nanoparticles are coated with bio-probes and dispersed in liquid. The bio-probes can then bind with homologous or heterologous bio-targets. When alternating-current (ac) magnetic fields are applied, magnetic nanoparticles rotate driven by ac magnetic fields. Thus, the bio-targets bound on the surface of magnetic nanoparticles experience a centrifugal force. The centrifugal force can be manipulated by adjusting the angular frequency of the rotating magnetic nanoparticles. The angular frequency is determined by the applied ac magnetic field frequency. Since the binding force for good binding is much higher than that of poor binding, frequency manipulation is needed for the centrifugal force to be higher than the poor-binding force but lower than the good-binding force. Therefore, poor binding which contributes to cross reactions between molecules can be suppressed efficiently by control of the ac magnetic field frequency.
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An YJ, Yang CY. Fridericia peregrinabunda (Enchytraeidae) as a new test species for soil toxicity assessment. CHEMOSPHERE 2009; 77:325-329. [PMID: 19683785 DOI: 10.1016/j.chemosphere.2009.07.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 07/07/2009] [Accepted: 07/13/2009] [Indexed: 05/28/2023]
Abstract
The present study proposes Fridericia peregrinabunda (Michaelsen, 1913) as a new test species for assessment of soil ecotoxicity. Fridericia is the richest genus in the Enchytraeidae family (Oligochaeta: Annelida: Clitellata: Enchytraeidae), and widely distributed. The acute toxicity of cadmium (Cd) and antimony (Sb) on the survival of F. peregrinabunda were investigated in laboratory experiments. Adult survival of F. peregrinabunda in metal spiked soil was reduced. Cadmium was more toxic to F. peregrinabunda than Sb. In the artificial soil toxicity tests, the LC50 values for F. peregrinabunda exposed to Cd and Sb for 48 h were 37, and 446 mg kg(-1), respectively. The NOEC values for Cd and Sb were 20 and 100 mg kg(-1) up to 48 h exposure, respectively. This is the first report on the ecotoxicological assay of contaminated soils using the enchytraeids F. peregrinabunda as a test species. It can be concluded that F. peregrinabunda is a suitable test species to measure the acute toxicity of heavy metals, and this species is more sensitive to Cd and Sb than earthworm. The filter paper contact test and 2 day-artificial soil toxicity test appear to be rapid and cost-effective protocols for the potworm assay.
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Yang CY, Xie ZG, Cheng WB, Jiang X, Chen ZH. [Effects of Panax notoginseng saponins on anti-hyperglycemic, anti-obese and prevention from kidney pathological changes in KK-Ay mice]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 2009; 32:1571-1576. [PMID: 20112724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To observe the effects of Panax notoginseng saponins (PNS) on anti-hyperglycemic, anti-obese and prevention from kidney pathological changes in a type 2 diabetic KK-Ay gene mice model. METHODS All animals were divided into 4 groups: Normal control group (C57BL/6J mice) were treated by NS 10 mL/kg, KK-Ay mice were subdivided into 3 groups as DM administrated NS 10 mL/kg, PNS 50 mg/kg, PNS 200 mg/kg respectively. All the animals received daily intraperitoneal injections for 30 days consecutively. All of these following items were determined as the effect of PNS: fasting plasma glucose levels (FPG), intraperitoneal glucose tolerance, body weight, food intake, insulin resistance index (IRI), serum insulin, triglyceride (TG), cholesterol (CH) levels and contribution of glomerulus injury. RESULTS On the 12th, 22nd and 30th day, PNS-treated group had significantly lower FPG and low body weight incremental percentage. After a 12-day treatment, glucose tolerance was significantly improved. On the 30th day the serum IRI and TG levels of PNS-treated group decreased significantly, and the development of the mice glomerular lesions was prevented significantly. All of these showed a dose-effect relationship. CONCLUSION PNS has the effects of anti-diabetes, anti-obese and prevention from kidney pathological changes in type 2 diabetic KK-Ay mice.
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Lei U, Huang CW, Chen J, Yang CY, Lo YJ, Wo A, Chen CF, Fung TW. A travelling wave dielectrophoretic pump for blood delivery. LAB ON A CHIP 2009; 9:1349-1356. [PMID: 19417900 DOI: 10.1039/b822809d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The travelling wave dielectrophoretic pump studied here is essentially a rectangular straight micro-channel with an electrode array on part of its wall, and operated under an ac voltage with phase shift at neighbouring electrodes. The travelling wave dielectrophoretic force drives the cells, which drag the plasma, and after some sophisticated interaction between conventional dielectrophoresis, travelling wave dielectrophoresis and fluid mechanics, the whole blood is delivered. The pump was fabricated using MEMS techniques and studied in details for different parameters. It is found that the pumping velocity is maximized at an intermediate frequency around 20-30 MHz (varies with phase shift), and at an intermediate channel height at about 40 microm. The quasi-static average cell velocity can reach 15 microm s(-1) for a pump with 1 mm length and 16 electrodes (total array length 465 microm) operated at 5 V and 20 MHz with 90 degrees phase shift.
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Nam SH, Yang CY, An YJ. Effects of antimony on aquatic organisms (Larva and embryo of Oryzias latipes, Moina macrocopa, Simocephalus mixtus, and Pseudokirchneriella subcapitata). CHEMOSPHERE 2009; 75:889-893. [PMID: 19264343 DOI: 10.1016/j.chemosphere.2009.01.048] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Revised: 01/13/2009] [Accepted: 01/15/2009] [Indexed: 05/27/2023]
Abstract
Antimony is widespread in aquatic environment. Trivalent forms of antimony are known to be more toxic than other chemical species of antimony. In the present study, antimony potassium tartrate (APT), the trivalent inorganic forms of antimony, was selected as a test antimony compound due to its high water solubility. The effects of antimony on Japanese medaka (Oryzias latipes), planktonic crustacea (Moina macrocopa and Simocephalus mixtus), and green algae (Pseudokirchneriella subcapitata) were evaluated. Larval survival and the embryonic development were measured for fish assay. APT was less toxic to larval medaka (24-h LC50, 261; 48-h LC50, 238 mg L(-1)). Simocephalus mixtus was killed by very low concentrations of APT (24-h LC50, 4.92 mg L(-1)), and antimony was also toxic to Moina macrocopa (24-h LC50, 12.83 mg L(-1)). Toxicities of APT to S. mixtus and Moina macrocopa were about 50 and 20 times more toxic to Oryzias latipes larvae, respectively, in terms of 24-h LC50 value. Growth inhibition of Pseudokirchneriella subcapitata was observed in the presence of APT (72-h EC50, 206 mg L(-1)). This study demonstrated that APT is more toxic to planktonic crustacea than fish and green algae, and planktonic crustacea appears a better indicator of antimony pollution in aquatic environment.
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Hsiao JK, Weng TI, Tai MF, Chen YF, Wang YH, Yang CY, Wang JL, Liu HM. Cellular behavior change of macrophage after exposure to nanoparticles. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:1388-1393. [PMID: 19441531 DOI: 10.1166/jnn.2009.c163] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Magnetic nanoparticles (MNPs) are few of the nanoparticles used clinically. When MNPs are delivered into human body, they are ingested by macrophages. We evaluated the cellular response of macrophage after MNPs loading. In face of stimulation by lipopolysaccharide, a strong stimulant derived from bacterial cell wall, MNPs loaded macrophage exhibited decreased phagocytic activity and decreased generation of cytokines such as TNF-alpha, IL-1beta whereas increased nitric oxide generation was noticed. Although these changes might decrease bactiericidal activity, it also alleviates the risk of senses, a life threatening phenomenon in infection patients. The finding has significant implications on nanoparticle based targeted drug delivery.
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Yang CY, Wang WB, Li DH, Liu YD. Growth and antioxidant system of Escherichia coli in response to microcystin-RR. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2008; 81:427-431. [PMID: 18714425 DOI: 10.1007/s00128-008-9436-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Accepted: 04/14/2008] [Indexed: 05/26/2023]
Abstract
Microcystins are a kind of cyclic hepatoxins produced by many species of cyanobacteria. The toxic effects of microcystins on animals and plants have been well studied. However, the reports about the effects of microcystins on microbial cells are very limited. In present paper, Escherichia coli was undertaken to determine the effect of microcystin-RR. These results suggested that microcystin-RR could prolong the growth of E. coli when exposed to high concentrations of microcystin-RR and cause the accumulation of ROS and induce the oxidant stress for a short time. The antioxidant system protects E. coli from oxidative damage.
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Hu J, He XJ, Feng YD, Yang CY, Han ZB, Gong JP. [Relationship of apoptotic receptor expression in normal human peripheral blood lymphocytes to cell apoptosis]. ZHONGGUO SHI YAN XUE YE XUE ZA ZHI 2007; 15:533-6. [PMID: 17605860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The aim of this study was to detect the expression and cell cycle specificity of Fas, TNFRI and TNFRII in human peripheral blood lymphocytes (PBL), and to study the potential role of Fas, TNFRIand TNFRII in cell cycle specific apoptosis. The improved double-parameter flow cytometry was used to detect the expressions of Fas, TNFRI and TNFRII and cell cycle specificity in PBL which were incubated for 24 hours in the presence or absence of phytohaematoagglutinin (PHA) respectively. Apoptosis induced by IgM type anti-Fas and TNF-alpha was detected by API method. The results showed that compared with PBL treated in the absence of PHA in G(0) phase, the ratio of Fas, TNFRI and TNFRII expressions in PHA-stimulated PBL entering cell cycle increased (35.55 +/- 6.63)%, (30.63 +/- 2.66)%, (26.62 +/- 5.14)% respectively (P < 0.01), and mainly appeared at G(1)-phase; no apoptosis was induced by anti-Fas and TNF-alpha in G(0)-phase PBL cultured in the absence of PHA. On the contrary, the apoptosis was induced by anti-Fas and TNF-alpha in PBL which entered cell cycle after stimulation with PHA and mainly initiated at G(1)-Phase. It is concluded that there is evident dose-effect relationship between apoptotic receptor and receptor-mediated apoptosis. Moreover, the cell cycle specificity of receptor-mediated apoptosis is correlated with the cell cycle specific expressions of apoptotic receptor. The induction of apoptosis by apoptotic factors (anti-Fas and TNF-alpha) depends on whether cell entering cell cycle or not.
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Chan YS, Chen ACY, Yuan LJ, Lin SS, Yang CY, Lee MSS, Ueng SWN. Effects of hyperbaric oxygen and platelet derived growth factor on medial collateral ligament fibroblasts. Undersea Hyperb Med 2007; 34:181-90. [PMID: 17672174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
PURPOSE This study investigated hyperbaric oxygen (HBO2) and platelet-derived growth factor-BB (PDGF-BB) to determine their combined effects on fibroblasts from rabbit medial collateral ligament (MCL). METHOD Cells were divided into four groups: (I) Control, (II) HBO2 treatment, (III) PDGF-BB treatment and (IV) HBO2 combined with PDGF-BB treatment. All hyperoxic cells were exposed to 100% O2 at 2.5 atmospheres absolute (ATA) in a hyperbaric chamber for 120 minutes per 48 hours. Measurement of cell growth was based on increase in cell number. Cell cycle modulations were analyzed by fluorescence-activated cell sorter (FACS). Quantity of Type I and Type III collagen was determined by western blotting and image analyzer. RESULTS Treatment doses of HBO2 alone or PDGF-bb alone dependently increased cell growth. A combination of HBO2 treatment plus PDGF-bb treatment had an additive effect on cell growth in comparison with HBO2 treatment alone or PDGF-bb treatment alone. FACS analysis revealed that HBO2 alone, PDGF-bb alone and PDGF-bb plus HBO2 treatment increase the percentage of cells accumulated in S-phase. Western blotting analysis revealed that Type III collagen content was decreased significantly after HBO2 treatment alone or HBO2 plus PDGF-bb treatment but not in PDGF-bb treatment alone. In contrast, although Type I collagen content was increased after HBO2 treatment, the increase in Type I collagen (increase /original) was not statistically significant. CONCLUSION HBO2 or HBO2 plus PDGF-bb treatment decreases the Type III collagen/Type I collagen content, which could result in mechanically stronger collagen fibrils. We propose HBO2 therapy as a potentially effective treatment for MCL healing.
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Yang CY, Chen CR, Chang E, Lee TM. Characteristics of hydroxyapatite coated titanium porous coatings on Ti-6Al-4V substrates by plasma sprayed method. J Biomed Mater Res B Appl Biomater 2007; 82:450-9. [PMID: 17245748 DOI: 10.1002/jbm.b.30750] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A porous metal coating applied to solid substrate implants has been shown, in vivo, to anchor implants by bone ingrowth. Calcium phosphate ceramics, in particular hydroxyapatite [Ca(10)(PO(4))(6)(OH)(2), HA], are bioactive ceramics, which are known to be biocompatible and osteoconductive, and these ceramics deposited on to porous-coated devices may enhance bone ingrowth and implant fixation. In this study, bi-feedstock of the titanium powder and composite (Na(2)CO(3)/HA) powder were simultaneously deposited on a Ti-6Al-4V substrate by a plasma sprayed method. At high temperature of plasma torch, the solid state of Na(2)CO(3) would decompose to release CO(2) gas and then eject the molten Ti powder to induce the interconnected pores in the coatings. After cleaning and soaking in deionized water, the residual Na(2)CO(3) in the coating would dissolve to form the open pores, and the HA would exist at the surface of pores in the inner coatings. By varying the particle size of the composite powder, the porosity of porous coating could be varied from 25.0 to 34.0%, and the average pore size of the porous coating could be varied to range between 158.5 and 202.0 microm. Using a standard adhesive test (ASTM C-633), the bonding strength of the coating is between 27.3 and 38.2 MPa. By SEM, the HA was observed at the surface of inner pore in the porous coating. These results suggest that the method exhibits the potential to manufacture the bioactive ceramics on to porous-coated specimen to achieve bone ingrowth fixation for biomedical applications.
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Yang CY, Lee TM, Yang CW, Chen LR, Wu MC, Lui TS. In vitro andin vivo biological responses of plasma-sprayed hydroxyapatite coatings with posthydrothermal treatment. J Biomed Mater Res A 2007; 83:263-71. [PMID: 17415765 DOI: 10.1002/jbm.a.31246] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This study was undertaken to evaluate the effect of post-hydrothermal treatment on the biological responses of the plasma-sprayed hydroxyapatite (HA)-coated Ti-6Al-4V implant system both in vitro and in vivo. After hydrothermal treatment, the HA coating (HAC) shows the high mechanical strength and indices-of-crystallinity, denser microstructure, lower concentrations of amorphous and impurity phases, when compared with the as-sprayed HAC. The in vitro cell-culture studies, using UMR106 osteoblast-like cell, demonstrated no signifiacnt cell growth on both surface of as-sprayed and hydrothermal-treated HACs during 10-day culture. The in vivo studies, using the transcortical implant model in the femora of goats, evaluated the histological responses of two coatings. After 6 week of implantation, using backscattered electron images, no substantial histological variations in the extents of new bone apposition and new bone healing between the two HACs were observed. However, the as-sprayed HAC, owing to the dissolution induced the granular particles dissociated from the HAC, showed the statically lower extent of new bone apposition than hydrothermal-treated HAC at 12 weeks. The results suggest that hydrothermal treatment could be used to improve the mechanical strength, crystallinity, and phase composition of HAC, which are important factors of long-term fixation and stability of implant. Besides, the treated HAC could also achieve the initial fixation of implant in clinical use.
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Yang CY, Chao PDL, Hou YC, Tsai SY, Wen KC, Hsiu SL. Marked decrease of cyclosporin bioavailability caused by coadministration of ginkgo and onion in rats. Food Chem Toxicol 2006; 44:1572-8. [PMID: 16762474 DOI: 10.1016/j.fct.2006.04.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Revised: 02/08/2006] [Accepted: 04/19/2006] [Indexed: 11/27/2022]
Abstract
Quercetin was reported to modulate CYP isoenzymes and P-glycoprotein (Pgp), a drug efflux transporter. Our previous study reported that quercetin significantly decreased the bioavailability of cyclosporin, a substrate for CYP3A4 and Pgp, in rats and pigs. Ginkgo and onion contain quercetin and its glycosides as St. John's Wort. The coadministration of cyclosporin with ginkgo or onion may be subject to clinically relevant interactions as St. John's Wort. Therefore, this study aimed to investigate the influences of ginkgo and onion on the absorption and disposition of cyclosporin in rats. Cyclosporin was administered orally and intravenously to rats with and without an oral dose of ginkgo or onion in crossover designs. Blood samples were collected via cardiopuncture and blood cyclosporin concentration was assayed by a specific monoclonal fluorescence polarization immunoassay. Everted gut sac was used to investigate the effects of ginkgo and onion on the function of intestinal Pgp. Oral coadministration of ginkgo and onion significantly decreased the Cmax of cyclosporin by 62% and 60%, and reduced the AUC0-t by 51% and 68%, respectively, whereas no influence was observed when cyclosporin was given intravenously. This indicates that the interactions between cyclosporin and ginkgo or onion occurred mainly at the absorption site. In conclusion, ginkgo and onion markedly decreased the oral bioavailability of cyclosporin. We suggest that concurrent intake of quercetin-rich herbs or foods with cyclosporin are better avoided in order to ensure the efficacy of cyclosporin.
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Yang CY, Xie DX, Zhou Y, Huang D, Gong JP. [Correlation of receptor-mediated apoptosis to cell cycle]. AI ZHENG = AIZHENG = CHINESE JOURNAL OF CANCER 2006; 25:576-81. [PMID: 16687077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
BACKGROUND & OBJECTIVE Chondriosome-mediated apoptosis is closely related to cell cycle, however, the correlation of receptor-mediated apoptosis to cell cycle progression is unclear yet. This study was to observe the receptor-mediated apoptosis and cell cycle specificity in cultured normal and tumor lymphocytes, and investigate their correlation. METHODS Exponentially growing human leukemia cell lines Molt-4 and Jurkat were treated with tumor necrosis factor-alpha (TNF-alpha) or Anti-Fas. Peripheral blood lymphocytes (PBLs) from healthy donors were stimulated by phytohemagglutinin (PHA), and further incubated with the presence of TNF-alpha or anti-Fas. Annexin V/PI was used to detect the apoptosis, and API method was used to illustrate the cell cycle specificity of apoptotic cells. RESULTS Unstimulated PBLs kept blunt to stimulation with TNF-alpha or anti-Fas, and the apoptotic rate was 6%-8%. Molt-4 cells, Jurkat cells, and stimulated PBLs which were treated with TNF-alpha or anti-Fas went to apoptosis, and the apoptosis rates were 15%-28%. Most receptor-mediated apoptosis happened in early G1 phase. CONCLUSION Receptor-mediated apoptosis is closely related to cell cycle and presents cell cycle specificity.
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Yang CY, Li CL, Lu CJ. A vapor selectivity study of microsensor arrays employing various functionalized ligand protected gold nanoclusters. Anal Chim Acta 2006. [DOI: 10.1016/j.aca.2006.02.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Chiu HF, Chen CC, Tsai SS, Wu TN, Yang CY. Relationship between magnesium levels in drinking water and sudden infant death syndrome. MAGNESIUM RESEARCH 2005; 18:12-8. [PMID: 15945612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The possible association between the risk of death from sudden infant death syndrome (SIDS) and the levels of magnesium in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. Characteristics for all SIDS deaths (501 cases) among Taiwan residents from 1988 through 1997 were compared with those of people who died from other causes (501 controls). The levels of magnesium in the drinking water of these residents were determined from data obtained from the Taiwan Water Supply Corporation (TWSC). The controls were pair-matched to the SIDS cases by sex, month and year of birth. The results of our study show that there is a significant trend towards a decreased risk of SIDS with increasing magnesium levels in drinking water.
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Xie XJ, Ran W, Shen QR, Yang CY, Yang JJ, Cao ZH. Field studies on 32P movement and P leaching from flooded paddy soils in the region of Taihu Lake, China. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2004; 26:237-243. [PMID: 15499779 DOI: 10.1023/b:egah.0000039586.12907.e9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Field experiments were done in two sites, Yixing and Changshu, Jiangsu province, China, to study P movement and leaching in flooded paddy soils. P movement in soil was investigated by using the KH2 32PO4 tracker method, and the amount of P leached from the soil layer in different depths was estimated by measuring P concentrations in the soil solution and saturated hydraulic conductivities in field. Determination was done about one month after P application. There was 46% and 42% of total 32P retained in the 0-5cm layer of soil in the Yixing site and in the Changshu site respectively. The 32P retained in the 25-30 cm layer was only about 1-2% of the total 32P added. Furthermore, 8.01% of 32P in the soil of Yixing site and 16.8% of 32P in the soil of Changshu site was lost from the layer 0-30 cm soil. The seasonal amounts of P leached from the top soil layer and from bottom layer are about 4.5-5.8% and 1.6-2.1% of the total P application, respectively. Changes of total P concentrations in soil solutions during rice growth showed that the fertilizer P applied before flooding of the paddy fields suffered a flash leaching loss and a slow leaching loss. We concluded that the fertilizer P could quickly move in the flooded paddy rice field and parts of it can enter into surface water and ground water. Unless the P application is well managed the risk of P loss and consequently environmental pollution exist.
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Yang CY, Zhao YP. Influences of hydration force and elastic strain energy on the stability of solid film in a very thin solid-on-liquid structure. J Chem Phys 2004; 120:5366-76. [PMID: 15267410 DOI: 10.1063/1.1648014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Since hydration forces become very strong at short range and are particularly important for determining the magnitude of the adhesion between two surfaces or interaction energy, the influences of the hydration force and elastic strain energy due to hydration-induced layering of liquid molecules close to a solid film surface on the stability of a solid film in a solid-on-liquid (SOL) nanostructure are studied in this paper. The liquid of this thin SOL structure is a kind of water solution. Since the surface forces play an important role in the structure, the total free energy change of SOL structures consists of the changes in the bulk elastic energy within the solid film, the surface energy at the solid-liquid interface and the solid-air interface, and highly nonlinear volumetric component associated with interfacial forces. The critical wavelength of one-dimensional undulation, the critical thickness of the solid film, and the critical thickness of the liquid layer are studied, and the stability regions of the solid film have been determined. Emphasis is placed on calculation of critical values, which are the basis of analyzing the stability of the very thin solid film.
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Lee TM, Yang CY, Chang E, Tsai RS. Comparison of plasma-sprayed hydroxyapatite coatings and zirconia-reinforced hydroxyapatite composite coatings:In vivo study. ACTA ACUST UNITED AC 2004; 71:652-60. [PMID: 15505828 DOI: 10.1002/jbm.a.30190] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The clinical use of plasma-sprayed hydroxyapatite (HA) coatings on metal implants has been widely adopted because the HA coating can achieve the firmly and directly biological fixation with the surrounding bone tissue. However, the long-term mechanical properties of HA coatings has been concern for the long-term clinical application. Previous research showed that the concept of adding ZrO2 as second phase to HA significantly increased the bonding strength of plasma-sprayed composite material. The present work aimed to explore the biological properties, including the histological responses and shear strength, between the plasma-sprayed HA and HA/ZrO2 coating, using the transcortical implant model in the femora of canines. After 6 and 12 weeks of implantation, the HA coating revealed the direct bone-to-coating contact by the backscattered electron images (BEIs) of scanning electron microscope (SEM), but the osseointegration was not observed at the surface of HA/ZrO2 coating. For new bone healing index (NBHI) and apposition index (AI), the values for HA implants were significantly higher than that for HA/ZrO2 coatings throughout all implant periods. After push-out test, the shear strength of HA-coated implants were statistically higher than HA/ZrO2 coated implants at 6- and 12-week implantation, and the failure mode of HA/ZrO2 coating was observed at the coating-bone interface by SEM. The results indicate that the firm fixation between bone and HA/ZrO2 has not been achieved even after 12-week implantation. Consequently, the addition of ZrO2 could improve the mechanical properties of coatings, while the biocompatibility was influenced by the different material characteristics of HA/ZrO2 coating compared to HA coatings.
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Lee TM, Chang E, Yang CY. Attachment and proliferation of neonatal rat calvarial osteoblasts on Ti6Al4V: effect of surface chemistries of the alloy. Biomaterials 2004; 25:23-32. [PMID: 14580905 DOI: 10.1016/s0142-9612(03)00465-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This study examined the cell attachment and proliferation of neonatal rat calvarial osteoblasts on Ti6Al4V alloy as affected by the surface modifications. The modifications could alter simultaneously the surface chemistries of the alloy (elemental difference of Ti, Al, V, Cu and Ni about 300-600mum thick examined by EDS) as well as the XPS nano-surface characteristics of oxides on the metal surface (chemistries of oxides, amphoteric OH group adsorbed on oxides, and oxide thickness). Three materials including two from modifications and a control were examined. It is argued that a slight change of the nano-surface characteristics of oxides as a result of the modifications neither alters the in vitro capability of Ca and P ion adsorption nor affects the metal ion dissolution behavior of the alloy. This implies that any influence on the cytocompatibility of the materials should only be correlated to the effect of surface chemistries of the alloy and the associated metal ion dissolution behavior of the alloy. The experimental results suggest that the cell response of neonatal rat calvarial osteoblasts on the Ti6Al4V alloy should neither be affected by the variation of surface chemistries of the alloy in a range studied.
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Yang CY, Meng CL, Liao CL, Wong PYK. Regulation of cell growth by selective COX-2 inhibitors in oral carcinoma cell lines. Prostaglandins Other Lipid Mediat 2003; 72:115-30. [PMID: 14674624 DOI: 10.1016/s1098-8823(03)00053-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Evidence indicates that NSAIDs that inhibit prostaglandin (PG) synthesis can reduce the incidence of colorectal cancers and that inhibition of cyclooxygenase-2 (COX-2) may be the underlying mechanism. The objective of this study was to investigate this putative mechanism by examining the effect of selective COX-2 inhibitors (Celebrex, DFU, NS-398) and COX-1 inhibitors (Aspirin) on the growth of two human oral carcinoma cell lines (OEC-M1 and KB) and one normal fibroblast cell line (NF). We found that the growth of OEC-M1 cells could be significantly inhibited by DFU concentrations above 30 microM (31%) after 4 days, and above 50 microM (35%) after 2 days in culture; by Celebrex at concentrations above 20 microM (52%) after 6 days, above 30 microM (36%) after 5 days, and above 40 microM (33%) after 4 days in culture; and by NS-398 above 1 microM (30%) after 6 days, and above 10 microM (35%) after 5 days in culture. The growth of KB cells could be significantly inhibited by DFU concentrations above 10 microM (33%) after 6 days, above 20 microM (35%) after 4 days in culture; and by Celebrex at concentrations above 10 microM (33%) after 5 days, and above 50 microM (30%) after 4 days in culture; and by NS-398 above 1 microM (45%) after 5 days, above 20 microM (36%) after 4 days in culture. The growth of NF cells could be significantly inhibited by DFU above 30 microM (45%) after 6 days, and above 40 microM (32%) after 3 days in culture, and by Celebrex at concentrations above 10 microM (42%) after 6 days, above 30 microM (31%) after 4 days, above 50 microM (32%) after 3 days in culture, and by NS-398 above 0.1 microM (35%) after 4 days, and above 1 microM (32%) after 3 days in culture. The growth-inhibitory concentration (IC50) values for DFU on OEC-M1, KB, and NF cells were about 39.1, 14.8, and 42.9 microM at 144 h, respectively, and on KB was about 45.2 microM at 120 h. The IC50 values for Celebrex on OEC-M1, KB, and NF cells were about 19.1, 8.6, and 15.8 microM at 144 h, respectively, and on KB and NF were about 27.7 and 35.3 microM, respectively, at 120 h. The IC50 values for NS-398 on OEC-M1, KB, and NF were about 18.9, 0.7 and 1 microM, respectively, at 144 h; on KB and NF values were about 10.8 and 1.4 microM, respectively, at 120 h and on KB and NF were about 26.6 and 4.1 microM, respectively, at 96 h. The results show that the growth of these cell lines is inhibited by three COX-2 selective inhibitors but not by any COX-1 selective inhibitors. These findings suggest that COX-2 may play an important role in the generation of biochemical mediators that stimulate the growth of human oral cancer and normal fibroblast cell lines.
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Niu KC, Lin KC, Yang CY, Lin MT. Protective effects of alpha-tocopherol and mannitol in both circulatory shock and cerebral ischaemia injury in rat heatstroke. Clin Exp Pharmacol Physiol 2003; 30:745-51. [PMID: 14516413 DOI: 10.1046/j.1440-1681.2003.03905.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. There is evidence that hydroxyl radicals are accumulated and oxidative stress is produced in multiple organs, including the brain, of rats with heat stroke. Herein, we investigated the effect on heat stroke-induced circulatory shock and cerebral ischaemic injury of two free radical scavengers, namely mannitol and alpha-tocopherol. 2. Urethane-anaesthetized rats were exposed to heat stress (ambient temperature 42 degrees C) to induce heat stroke. Control rats were exposed to 24 degrees C. Mean arterial pressure and cerebral blood flow after the onset of heat stroke were significantly lower in heat stroke rats than in control rats. However, cerebral free radicals, lipid peroxidation and the neuronal damage score were greater in heat stroke rats compared with control rats. Similarly, plasma cytokines, including tumour necrosis factor-alpha, interleukin (IL)-1beta and IL-6, were significantly higher in heat stroke rats compared with their normothermic controls. 3. Pretreatment with alpha-tocopherol (20 mg/kg, i.v.) or mannitol (10%, i.v.) 30 min before the onset of heat exposure significantly attenuated heat stroke-induced arterial hypotension, cerebral ischaemia and neuronal damage, the increased free radical formation and lipid peroxidation in the brain and the increased plasma levels of cytokines. Pretreatment with alpha-tocopherol or mannitol resulted in a prolongation of survival time in heat stroke. 4. These results demonstrate that although pretreatment with alpha-tocopherol and mannitol does not prevent the heat stroke syndrome entirely, an attenuation of the syndrome is observed.
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Lin HR, Kuo CJ, Yang CY, Shaw SY, Wu YJ. Preparation of macroporous biodegradable PLGA scaffolds for cell attachment with the use of mixed salts as porogen additives. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2003; 63:271-9. [PMID: 12115758 DOI: 10.1002/jbm.10183] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In the present study, a mixture of ammonium-bicarbonate (NH(4)HCO(3)) and sodium-chloride (NaCl) particles was used as a porogen additive to fabricate highly macroporous biodegradable poly(lactic-co-glycolic acid) (PLGA) scaffolds. A two-step salt-leaching process was performed after the sample had become semisolidified. Compared to the standard solvent-casting/particulate-leaching (SC/PL) technique, the processing time of this approach was significantly shorter: Instead of several days, only half a day was required. In addition, the polymer/salts/solvent mixture can be easily handled and molded into scaffolds of any specific shape-for example, thin sheet, cylindrical, or bone-shaped-for special applications in tissue engineering. Our results demonstrate that these scaffolds have a highly interconnected open-pore structure as well as greater mechanical properties than those made using the standard SC/PL technique. Primary rat osteoblasts seeded into the scaffolds exhibited good seeding efficiency. The method presented here is a promising approach for fabricating scaffolds for tissue engineering applications.
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Hong CJ, Cheng CY, Shu LRR, Yang CY, Tsai SJ. Association study of the dopamine and serotonin transporter genetic polymorphisms and methamphetamine abuse in Chinese males. J Neural Transm (Vienna) 2003; 110:345-51. [PMID: 12658362 DOI: 10.1007/s00702-002-0790-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The dopamine transporter (DAT) and the serotonin transporter (5-HTT) play important roles in methamphetamine (METH) dependence because they are the target of METH action. For this study, the association between the DAT and 5-HTT polymorphisms and METH dependence were investigated for a Chinese-male sample population. The investigated polymorphisms included those of the DAT 3'-variable number tandem repeat, the 5-HTT gene promoter and a 5-HTT variable number tandem repeat polymorphisms. No significant difference was demonstrated for genotype or allele frequency, when comparing METH dependent and control cases for the DAT and the 5-HTT polymorphisms. The findings of this study suggest that these polymorphisms do not play major roles in METH dependence in the Chinese-male population.
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Chuang CY, Hung JC, Yang CY, Ma YC, Sung FC. Plasma nitrogen oxides levels in taxi drivers and community residents. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2003; 70:430-436. [PMID: 12592514 DOI: 10.1007/s00128-003-0004-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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Xue HG, Yamamoto N, Yoshimoto M, Yang CY, Ito H. Fiber connections of the nucleus isthmi in the carp (Cyprinus carpio) and tilapia (Oreochromis niloticus). BRAIN, BEHAVIOR AND EVOLUTION 2002; 58:185-204. [PMID: 11964496 DOI: 10.1159/000057563] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The nucleus pretectalis (NP) is a prominent nucleus in the percomorph pretectum and has been shown to project to the nucleus isthmi in the filefish by an HRP tract-tracing method [Ito et al., 1981], but a homologous nucleus to the NP is apparently lacking in ostariophysans. The present study examined fiber connections of the nucleus isthmi in an ostariophysan teleost, the carp (Cyprinidae, Cyprinus carpio), to identify a nucleus homologous to the percomorph nucleus pretectalis. Identical studies in a percomorph tilapia (Cichlidae, Oreochromis niloticus) were also performed. Injections of biotinylated dextran amine (BDA) or biocytin to the carp nucleus isthmi labeled cells in the ipsilateral optic tectum and nucleus ruber of Goldstein [1905]. Labeled tectal neurons were located in the stratum periventriculare (SPV) and the stratum fibrosum et griseum superficiale (SFGS). The somata in the SPV were pyriform and those in the SFGS were fusiform. No labeled cells were found in the pretectum. Labeled terminals were seen in the ipsilateral nucleus pretectalis superficialis pars parvocellularis (PSp), optic tectum, and bilateral nucleus ruber. Terminals in the nucleus ruber appear to come from tectal neurons in the SFGS labeled by isthmic injections. Thus the nucleus isthmi has reciprocal fiber connections with the ipsilateral optic tectum, receives projections from the ipsilateral nucleus ruber, and projects to the ipsilateral PSp. The nucleus pretectalis homologue is apparently absent in the carp. Studies in tilapia showed that the nucleus isthmi receives bilateral projections from the NP and optic tectum. In addition, the present study revealed a previously unknown afferent from the nucleus ruber to the percomorph nucleus isthmi. The tilapia nucleus isthmi projects to the same targets as in the carp. Isthmic projection neurons in the tilapia optic tectum were located in the SPV and pyriform with a similar shape to the carp SPV neurons that project to the nucleus isthmi. No labeled cells were found in the SFGS of tilapia optic tectum. The fusiform neurons in the SFGS of the carp optic tectum possess various hodological similarities with the NP and may correspond to the NP neurons of percomorphs.
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