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Hsieh JG, Lin YL, Jeng JH. Preliminary study on wilcoxon learning machines. IEEE TRANSACTIONS ON NEURAL NETWORKS 2008; 19:201-11. [PMID: 18269953 DOI: 10.1109/tnn.2007.904035] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
As is well known in statistics, the resulting linear regressors by using the rank-based Wilcoxon approach to linear regression problems are usually robust against (or insensitive to) outliers. This motivates us to introduce in this paper the Wilcoxon approach to the area of machine learning. Specifically, we investigate four new learning machines, namely Wilcoxon neural network (WNN), Wilcoxon generalized radial basis function network (WGRBFN), Wilcoxon fuzzy neural network (WFNN), and kernel-based Wilcoxon regressor (KWR). These provide alternative learning machines when faced with general nonlinear learning problems. Simple weights updating rules based on gradient descent will be derived. Some numerical examples will be provided to compare the robustness against outliers for various learning machines. Simulation results show that the Wilcoxon learning machines proposed in this paper have good robustness against outliers. We firmly believe that the Wilcoxon approach will provide a promising methodology for many machine learning problems.
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Da Silva BA, Li J, Lin YL, Noertersheuser PA, Awni WM, Klein CE, Doan TT, Bernstein B. Evaluation of the impact of lopinavir/ritonavir (LPV/r) and ritonavir (RTV) on PR interval: results from a thorough QT study. J Int AIDS Soc 2008. [DOI: 10.1186/1758-2652-11-s1-p101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Chen SP, Lee MC, Sun YF, Cheng IC, Yang PC, Lin YL, Jong MH, Robertson ID, Edwards JR, Ellis TM. Immune responses of pigs to commercialized emulsion FMD vaccines and live virus challenge. Vaccine 2007; 25:4464-9. [PMID: 17445957 DOI: 10.1016/j.vaccine.2007.03.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Revised: 02/03/2007] [Accepted: 03/08/2007] [Indexed: 11/26/2022]
Abstract
The immune response to structural and non-structural proteins (NSPs) was studied on sequential serum samples in swine from O/Taiwan/97 FMDV challenge studies, outbreaks and after vaccination. The results showed that pigs vaccinated with a commercial vaccine prior to or after infection maintained high neutralizing antibody titers with gradual decline from peak titers over the duration of this study. However, neutralizing antibody titers in non-vaccinated pigs only reached moderate levels 2-4 weeks post infection and remained low thereafter. For the 3B and 3ABC NSP antibody ELISA responses, there were gradually decreasing levels of NSP antibody over time. In multiple vaccinations, all pigs showed significant increases in neutralizing antibodies after booster vaccination. For the 3B NSP antibody ELISA after vaccination, the mean S/P ratios for pigs vaccinated with all three FMD vaccines were all below the 0.23 cut-off value set by the manufacture, but some sera from individual vaccinated pigs gave results above this cut-off after primary or secondary vaccination. However, with the 3ABC NSP antibody ELISA, all sera from vaccinated pigs had negative results for NSP antibody for all time points.
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Chen SP, Ellis TM, Lee MC, Cheng IC, Yang PC, Lin YL, Jong MH, Robertson ID, Edwards JR. Comparison of sensitivity and specificity in three commercial foot-and-mouth disease virus non-structural protein ELISA kits with swine sera in Taiwan. Vet Microbiol 2007; 119:164-72. [PMID: 17112687 DOI: 10.1016/j.vetmic.2006.09.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 09/14/2006] [Accepted: 09/18/2006] [Indexed: 11/22/2022]
Abstract
Three commercialized ELISA kits for the detection of antibodies to the non-structural proteins (NSPs) of FMD virus were compared, using sera from uninfected, vaccinated, challenged and naturally infected pigs. The kinetics of the antibody response to NSPs was compared on sequential serum samples in swine from challenge studies and outbreaks. The results showed that ELISA A (UBI) and ELISA B (CEDI) had better sensitivity than that of the 3ABC recombinant protein-based ELISA C (Chekit). The peak for detection of antibodies to NSPs in ELISA C was significantly delayed in sera from natural infection and challenged swine as compared to the ELISA A and B. The sensitivity of the three ELISAs gradually declined during the 6-month post-infection as antibodies to NSP decline. ELISA kits A and B detected NSP antibody in 50% of challenged pigs by the 9-10th-day and 7-8th-day post-challenge, respectively. ELISA B and C had better specificity than ELISA A on sequential serum samples obtained from swine immunized with a type O FMD vaccine commercially available in Taiwan. Antibody to NSPs before vaccination was not detected in swine not exposed to FMD virus, however, antibody to NSPs was found in sera of some pigs after vaccination. All assays had significantly lower specificity when testing sera from repeatedly vaccinated sows and finishers in 1997 that were tested after the 1997 FMD outbreak. However, when testing sera from repeatedly vaccinated sows or finishers in 2003-2004, the specificity for ELISAs A, B and C were significantly better than those in 1997. This effect was less marked for ELISA A. The ELISA B was the best test in terms of the highest sensitivity and specificity and the lowest reactivity with residual NSP in vaccinates.
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Chang EE, Chiang PC, Chao SH, Lin YL. Relationship between chlorine consumption and chlorination by-products formation for model compounds. CHEMOSPHERE 2006; 64:1196-203. [PMID: 16412493 DOI: 10.1016/j.chemosphere.2005.11.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Revised: 11/10/2005] [Accepted: 11/10/2005] [Indexed: 05/06/2023]
Abstract
The objective of this research is to investigate the relationship between chlorine decay and the formations of disinfection by-products (DBP), including trichloromethane (TCM) and chloroacetic acid (CAA) in the presence of four model compounds, i.e., resorcinol, phloroglucinol, p-hydroxybenzoic acid, and m-hydroxybenzoic acid. The chlorine degradation in model compounds with OH and/or COOH functional groups were rapid after chlorination. The TCM yields of carboxylic group substituted compounds (3-hydroxybenzoic acid [3-HBA], 4-hydroxybenzoic acid [4-HBA]) were found to be lower than that of the m-dihydroxy substituted compounds. Phloroglucinol, with one more OH substitution group than resorcinol, tends to form significant amounts of CAA after chlorination. However, it was observed that with the COOH substitution of 3-HBA and 4-HBA tend to exhibit more CAA formation potential than resorcinol. The developed parallel second and first-order reaction model for chlorine demand has been successfully utilized for TCM, CAA and DBP formation modeling. A high correlation between CAA and TCM was observed for the model compounds.
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Lo YC, Lin YL, Yu KL, Lai YH, Wu YC, Ann LM, Chen IJ. San-Huang-Xie-Xin-Tang attenuates inflammatory responses in lipopolysaccharide-exposed rat lungs. JOURNAL OF ETHNOPHARMACOLOGY 2005; 101:68-74. [PMID: 15878812 DOI: 10.1016/j.jep.2005.03.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 02/21/2005] [Accepted: 03/24/2005] [Indexed: 05/02/2023]
Abstract
In this study, the potential anti-inflammatory effect of San-Huang-Xie-Xin-Tang (SHXT) and its main component baicalin on LPS-induced lung injury were investigated and compared to the profile of dexamethasone (DEXA) in a pre-clinical animal model. Post-treatment with SHXT (75 mg/kg), baicalin (1.5 mg/kg) and DEXA (0.5 mg/kg), significantly inhibited LPS-induced hypotension, lung edema and acute survival rates. Western blotting analysis results indicated that all of them significantly inhibited LPS-induced iNOS, TGF-beta, p38MAPK, and ICAM-1 expressions in the lung tissues. Results from ELISA analysis showed that SHXT, baicalin and DEXA all decreased plasma levels of IL-1beta, TNF-alpha, and MCP-1 caused by LPS. Based on these findings, SHXT and baicalin decreased plasma concentrations of IL-1beta, TNF-alpha, MCP-1, and expressions of TGF-beta, ICAM-1, phosphorylated p38 MAPK, and iNOS, which were associated with lung injury and lethality. These evidences indicated that SHXT and baicalin showed strong anti-inflammatory activity, similar to that observed for DEXA, and therefore implicated that herbal SHXT might be therapeutically useful for the treatment of endotoxic lung injury.
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Lin YL, Brama PAJ, Kiers GH, van Weeren PR, DeGroot J. Extracellular Matrix Compositon of the Equine Superficial Digital Flexor Tendon: Relationship with Age and Anatomical Site. ACTA ACUST UNITED AC 2005; 52:333-8. [PMID: 16109099 DOI: 10.1111/j.1439-0442.2005.00742.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The objectives of the present study were to test the hypotheses that: (1) the composition of the extracellular matrix of the equine superficial digital flexor tendon (SDFT) shows great functional similarities with articular cartilage, i.e. that significant differences exist in biochemical composition of differently loaded areas (which in the case of tendons may be more apparent as tendon shows more obvious differences than cartilage); and (2) that, as in articular cartilage, no substantial alterations in biochemical composition take place during ageing once adulthood has been attained. Tendon samples were taken from 60 adult slaughter horses from a central area at cross-section in the mid-metacarpal region and at the height of the proximal sesamoid bones (sesamoid region) of the SDFT. Contents of collagenous and non-collagenous components were determined. None of the parameters were correlated with age in either region, except for a significant increase in pentosidine cross-links with age in the sesamoid region. Between the two anatomical regions, there were significant differences in all variables, except for hydroxylysylpyridinoline cross-links. It was concluded that in the equine SDFT, similar to articular cartilage, most molecular parameters are not influenced by age in mature horses, indicating a low remodelling rate. Tendon composition is clearly different between regions, apparently reflecting different specific modes of biomechanical loading at the points sampled.
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Liao PC, Lin YL, Jong MH, Chung WB. Efficacy of foot-and-mouth disease vaccine in pigs with single dose immunization. Vaccine 2003; 21:1807-10. [PMID: 12706663 DOI: 10.1016/s0264-410x(03)00030-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Two experiments were conducted to demonstrate the efficacy of a commercial foot-and-mouth disease (FMD) vaccine in pigs born to well-vaccinated sows at various ages with a single injection under field conditions. The first experiment showed that single dose vaccination of pigs could be conducted at an age younger than 10 weeks. Second experiment demonstrated that pigs vaccinated once at the age of 8 weeks had mean serum neutralization (SN) titer of 1.89+/-0.95 log(10)SN(50) with full protection by challenge test at the age of 24 weeks. Results indicate that the most appropriate age for single dose FMD vaccination in pigs born to well-vaccinated sows would be at 8 weeks.
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Abstract
Acute appendicitis is the most common cause of abdominal pain requiring surgery in children. But it is an uncommon entity in young children and rare in infants. During a 10-year period, between January 1991 and December 2000, 7 infants (age from 17 days to 8 months) were treated for acute appendicitis at Changhua Christian Hospital. All of the preoperative symptoms and signs, the duration between admission and operation, pathology reports, and laboratory data were reviewed. There were no specific clinical signs and symptoms. The duration between admission and operation ranged from 2 hours to 5 days (mean: 31.4 hours). The pathology reports revealed 3 were gangrenous, 3 were gangrenous with perforation and one was suppurative. There was one death. Pseudomonas aeruginosa was cultured from blood, ascites, bile or stool in 6 cases (85.7%). Early diagnosis of acute appendicitis in infants is still difficult. Although the mortality has declined, the morbidity still remains high. The high percentage of infection by Pseudomonas aeruginosa should be further evaluated in infantile appendicitis.
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Chung WB, Liao PC, Chen SP, Yang PC, Lin YL, Jong MH, Sheu TW. Optimization of foot-and-mouth disease vaccination protocols by surveillance of neutralization antibodies. Vaccine 2002; 20:2665-70. [PMID: 12034091 DOI: 10.1016/s0264-410x(02)00201-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
An appropriate immunization program for pigs in a foot-and-mouth disease (FMD) endemic area was proposed based on data analysis obtained from serological surveillance in Taiwan, after an intensive vaccination program. To provide an adequate passive immunity for piglets, gilts that have completed two basic vaccinations must be boosted once before breeding. To achieve an efficient response to the FMD vaccine for piglets born to well vaccinated sows, vaccination need to be delayed until 10-12 weeks of ages for the first immunization, followed by a boost 4 weeks later.
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Ou LS, See LC, Wu CJ, Kao CC, Lin YL, Huang JL. Association between serum inflammatory cytokines and disease activity in juvenile idiopathic arthritis. Clin Rheumatol 2002; 21:52-6. [PMID: 11954886 DOI: 10.1007/s100670200012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Circulating interleukin-1beta (IL-1beta), IL-6, tumour necrosis factor-alpha (TNF-alpha), osteocalcin, and conventional parameters of inflammation were examined serially in 14 children with juvenile idiopathic arthritis (JIA) to determine any correlation with the disease activity. Serum IL-1beta was undetectable in all JIA patients. Serum IL-6, white blood cell counts, platelet counts, erythrocyte sedimentation rate and C-reactive protein levels were significantly elevated in the active phase of JIA, whereas hemoglobin levels were significantly lower. Osteocalcin levels were decreased and TNF-alpha increased in active JIA status, but these differences showed no statistical significance. We concluded that inflammatory cytokines play an important role in JIA. Monitoring IL-6 in children with JIA is useful in determining disease activity and response to therapy. These findings confirm earlier reports.
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Lin YL, Turos E. Studies of silyl-accelerated 1,5-hydrogen migrations in vinylcyclopropanes. J Org Chem 2001; 66:8751-9. [PMID: 11749603 DOI: 10.1021/jo0103221] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thermal 1,5-hydrogen (retro-ene) rearrangements of 1-silylmethylated 2-vinylcyclopropanes have been studied. cis-1-Silylmethyl-2-vinylcyclopropanes 17 and 19 undergo facile 1,5-hydrogen transposition upon mild thermolysis in benzene or toluene solution (80-110 degrees C) to give nearly quantitative yields of ring-opened 1-silyl-1,4-diene products. These reactions occur at temperatures at least 100 degrees C lower than those of the nonsilylated substrates. The silicon center and its ligands influence both the rate and stereoselectivity of diene formation, with the triphenylsilyl substrate providing the fastest reaction and highest (exclusive) stereoselectivity in forming the diene, regardless of the E/Z geometry of the vinylcyclopropane. The trimethylsilyl and triethoxysilyl compounds (19b and 19c) rearrange more slowly and with lower stereoselectivity. It is proposed that the rearrangement process takes place via a concerted suprafacial migration by one of two diastereotopic methylene hydrogens through a transition state having the silyl-carbon bond antiperiplanar to the breaking C-C bond of the cyclopropane ring. This conformational arrangement leads to weakening of the cyclopropane ring bond through orbital hyperconjugation, which facilitates the hydrogen transfer. The corresponding trans-1-silylmethyl-2-vinylcyclopropanes are thermally stable under these conditions. In contrast, cis-1-stannylmethyl-2-vinylcyclopropanes 19d,e undergo loss of the stannyl group at room temperature to afford a ring-opened 1,5-diene product 25 through a process that may take place by initial 1,5-stannyl migration.
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Ueng YF, Shyu CC, Liu TY, Oda Y, Lin YL, Liao JF, Chen CF. Protective effects of baicalein and wogonin against benzo[a]pyrene- and aflatoxin B(1)-induced genotoxicities. Biochem Pharmacol 2001; 62:1653-60. [PMID: 11755119 DOI: 10.1016/s0006-2952(01)00816-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To evaluate the protective effects of baicalein and wogonin against benzo[a]pyrene- and aflatoxin (AF) B(1)-induced toxicities, the effects of these flavonoids on the genotoxicities and oxidation of benzo[a]pyrene and AFB(1) were studied in C57BL/6J mice. Baicalein and wogonin reduced benzo[a]pyrene and AFB(1) genotoxicities as monitored by the umuC gene expression response in Salmonella typhimurium TA1535/pSK1002. Baicalein added in vitro decreased liver microsomal benzo[a]pyrene hydroxylation (AHH) activity with an ic(50) of 33.9 +/- 1.4 microM at 100 microM benzo[a]pyrene. Baicalein also inhibited AFQ(1) and AFB(1)-epoxide formation from AFB(1) (50 microM) oxidation (AFO) with ic(50) values of 22.8 +/- 1.4 and 5.3 +/- 0.8 microM, respectively. However, the in vitro inhibitory effects of wogonin on AHH and AFO activities in liver microsomes were less than those of baicalein as inhibition by 500 microM wogonin was only about 51-65%. Treatment of mice with liquid diets containing 5 mM baicalein and wogonin resulted in 22 and 49% decreases in hepatic AHH activities, respectively. Baicalein treatment resulted in 39 and 32% decreases in AFQ(1) and AFB(1)-epoxide formation from liver microsomal AFO, respectively. Wogonin treatment resulted in 39 and 47% decreases in AFQ(1) and AFB(1)-epoxide formation, respectively. A 1-week pretreatment with wogonin significantly decreased hepatic DNA adduct formation in mice treated with 200 mg/kg of benzo[a]pyrene via gastrogavage. These in vitro and in vivo effects suggested that baicalein and wogonin might have beneficial effects against benzo[a]pyrene- and AFB(1)-induced hepatic toxicities and that wogonin had a stronger protective effect in vivo.
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Chen HP, Wu SH, Lin YL, Chen CM, Tsay SS. Cloning, sequencing, heterologous expression, purification, and characterization of adenosylcobalamin-dependent D-ornithine aminomutase from Clostridium sticklandii. J Biol Chem 2001; 276:44744-50. [PMID: 11577113 DOI: 10.1074/jbc.m108365200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
D-Ornithine aminomutase from Clostridium sticklandii catalyzes the reversible rearrangement of d-ornithine to (2R,4S)-2,4-diaminopentanoic acid. The two genes encoding d-ornithine aminomutase have been cloned, sequenced, and expressed in Escherichia coli. The oraS gene, which encodes a protein of 121 amino acid residues with M(r) 12,800, is situated upstream of the oraE gene, which encodes a protein of 753 amino acid residues with M(r) 82,900. The holoenzyme appears to comprise a alpha(2)beta(2)-heterotetramer. OraS shows no significant homology to other proteins in the Swiss-Prot data base. The deduced amino acid sequence of OraE includes a conserved base-off/histidine-on cobalamin-binding motif, DXHXXG. OraE was expressed in E. coli as inclusion bodies. Refolding experiments on OraE indicate that the interactions between OraS and OraE and the binding of either pyridoxal phosphate or adenosylcobalamin play important roles in refolding process. The K(m) values for d-ornithine, 5'-deoxyadenosylcobalamin (AdoCbl), and pyridoxal 5'-phosphate (PLP) are 44.5 +/- 2.8, 0.43 +/- 0.04, and 1.5 +/- 0.1 microm, respectively; the k(cat) is 6.3 +/- 0.1 s(-1). The reaction was absolutely dependent upon OraE, OraS, AdoCbl, PLP, and D-ornithine being present in the assay; no other cofactors were required. A red-shift in UV-visible absorption spectrum is observed when free adenosylcobinamide is bound by recombinant D-ornithine aminomutase and no significant change in spectrum when free adenosylcobinamide is bound by mutant OraE-H618G, demonstrating that the enzyme binds adenosylcobalamin in base-off/histidine-on mode.
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Huang FJ, Lin YL. Effects of retinoic acid on pre-implantation embryo development in mice. CHANG GUNG MEDICAL JOURNAL 2001; 24:681-7. [PMID: 11820648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
BACKGROUND In a previous study we had investigated the effect of in utero retinoic acid (RA) exposure on early post-implantation development at the blastocyst stage before implantation and immediately after implantation to understand the possible roles of RA in embryogenesis. The results showed that excess RA affected early post-implantation embryogenesis adversely. We designed the present study to investigate the effect of in utero RA exposure on pre-implantation embryos. METHODS In the prospective animal study, pregnant female mice received early pre-implantation peanut oil with 50 mg/kg t-RA or 100 mg/kg t-RA by oral gavage on the morning of day 1 and 2 or late pre-implantation exposure on the night of day 2 and morning of day 3 of gestation. Mice were sacrificed late in day 3. The number and morphology embryos were recorded. RESULTS All mice given oral RA were sacrificed on the same day. The mean number of embryos per mouse and the percentage of different embryo stages in the t-RA treated mice administered at early pre-implantation embryo or late pre-implantation embryo stage were not significantly different from the controls. The mean number of embryos per 50 mg/kg mouse and the percentage of expanded blastocysts or early blastocysts/morulas did not differ from controls. In addition, the percentage of expanded blastocysts or early blastocysts/morulas was also not significantly different from the control group in 100 mg/kg late pre-implantation mice. CONCLUSION Mouse embryo development may not experience dose related adverse effects from non-physiological RA exposure during pre-implantation.
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Huang JL, Huang JH, Shyu RH, Teng CW, Lin YL, Kuo MD, Yao CW, Shaio MF. High-level expression of recombinant dengue viral NS-1 protein and its potential use as a diagnostic antigen. J Med Virol 2001; 65:553-60. [PMID: 11596093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The prevalence of NS1 Ab response in patients with dengue viral infection and the potential of using recombinant NS1 protein as a diagnostic antigen for dengue viral infection were investigated. In this study, the full-length and C-terminal half of NS1 proteins (rNS1, rNS1-C) were highly expressed (10-30 mg/l) and further purified and refolded. The good antigenicity of the full-length rNS1 protein was confirmed by interaction with 19 dengue NS1-specific monoclonal antibodies (MAbs) in ELISA; however, the antigenicity of rNS1-C was relatively lower. The full-length rNS1 antigen also differentiated reliably between sera from dengue virus-infected patients and sera from normal controls. When rNS1 was used as an antigen to detect human anti-NS1 IgM and IgG Ab, the anti-NS1 Ab response was found in 15 of 17 patients (88%) with primary dengue infection and all 16 patients (100%) with secondary dengue infection. These results indicated that using the full-length rNS1 whose antigenicity is restored as ELISA antigen, a high anti-NS1 antibody prevalence could be detected in patients with either primary or secondary dengue infection. This finding suggested that the anti-NS1 antibody appeared not only in secondary and severe dengue virus infection and might not correlate the pathogenesis of dengue hemorrhagic fever. The study also verified that our purified rNS1 protein showed similar immunological properties as native dengue viral proteins. Genetic engineering production of recombinant NS1 antigen could provide a safe and valuable resource for dengue virus serodiagnosis.
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Liao CL, Lin YL, Wu BC, Tsao CH, Wang MC, Liu CI, Huang YL, Chen JH, Wang JP, Chen LK. Salicylates inhibit flavivirus replication independently of blocking nuclear factor kappa B activation. J Virol 2001; 75:7828-39. [PMID: 11483726 PMCID: PMC115025 DOI: 10.1128/jvi.75.17.7828-7839.2001] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Flaviviruses comprise a positive-sense RNA genome that replicates exclusively in the cytoplasm of infected cells. Whether flaviviruses require an activated nuclear factor(s) to complete their life cycle and trigger apoptosis in infected cells remains elusive. Flavivirus infections quickly activate nuclear factor kappa B (NF-kappaB), and salicylates have been shown to inhibit NF-kappaB activation. In this study, we investigated whether salicylates suppress flavivirus replication and virus-induced apoptosis in cultured cells. In a dose-dependent inhibition, we found salicylates within a range of 1 to 5 mM not only restricted flavivirus replication but also abrogated flavivirus-triggered apoptosis. However, flavivirus replication was not affected by a specific NF-kappaB peptide inhibitor, SN50, and a proteosome inhibitor, lactacystin. Flaviviruses also replicated and triggered apoptosis in cells stably expressing IkappaBalpha-DeltaN, a dominant-negative mutant that antagonizes NF-kappaB activation, as readily as in wild-type BHK-21 cells, suggesting that NF-kappaB activation is not essential for either flavivirus replication or flavivirus-induced apoptosis. Salicylates still diminished flavivirus replication and blocked apoptosis in the same IkappaBalpha-DeltaN cells. This inhibition of flaviviruses by salicylates could be partially reversed by a specific p38 mitogen-activated protein (MAP) kinase inhibitor, SB203580. Together, these results show that the mechanism by which salicylates suppress flavivirus infection may involve p38 MAP kinase activity but is independent of blocking the NF-kappaB pathway.
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Lin YL, Wang WY, Kuo YH, Liu YH. Homocyclotirucallane and two dihydrophenanthrenes from Spiranthes sinensis. Chem Pharm Bull (Tokyo) 2001; 49:1098-101. [PMID: 11558594 DOI: 10.1248/cpb.49.1098] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A novel homocyclotirucallane, sinetirucallol (1), and two additional new dihydrophenanthrenes, sinensols G (2) and H (3), were isolated from the aerial parts of Spiranthes sinensis (Pers.) Ames. Their structures were determined by various spectral analyses, including MS and two-dimentional nuclear magnetic resonance techniques. The structure of compound 1 was further confirmed by single-crystal X-ray analysis. The absolute configuration of 1 was determined by modified Mosher's method.
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Wang CY, Chang TY, Walfield AM, Ye J, Shen M, Zhang ML, Lubroth J, Chen SP, Li MC, Lin YL, Jong MH, Yang PC, Chyr N, Kramer E, Brown F. Synthetic peptide-based vaccine and diagnostic system for effective control of FMD. Biologicals 2001; 29:221-8. [PMID: 11851319 DOI: 10.1006/biol.2001.0302] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have designed synthetic peptides corresponding to two different regions of the genome of foot-and-mouth disease virus (FMDV) that are effective as (a) a vaccine or (b) a diagnostic reagent which differentiates convalescent from vaccinated animals, respectively. The peptide vaccine is based on a sequence from the prominent G-H loop of VP1, one of the four capsid proteins. The sequence was optimized by the inclusion of a cyclic constraint and adjoining sequences, and broader immunogenicity was obtained by the incorporation of consensus residues at hypervariable positions. The peptide also included a promiscuous T-helper epitope for effective immunogenicity in outbred populations of large animals.The diagnostic reagent, a peptide based on non-structural (NS) protein 3B, is used in immuno-assays for the detection of antibodies. Antibodies to this NS protein are present in the sera of infected animals but not in the sera of vaccinated animals. The VP1 peptide can be used in complementary immuno-assays for confirmation of NS test results and to monitor for vaccination. This system for differential diagnosis is important to establish the disease-free status of a country.
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Huang CC, Lin YL, Huang TS, Tu WJ, Lee SH, Jong MH, Lin SY. Molecular characterization of foot-and-mouth disease virus isolated from ruminants in Taiwan in 1999-2000. Vet Microbiol 2001; 81:193-205. [PMID: 11390103 DOI: 10.1016/s0378-1135(01)00308-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In 1999, 10 sporadic outbreaks of cattle foot-and-mouth disease (FMD) occurred in Taiwan. By the time, infection was limited to the Chinese yellow cattle (a native species of beef cattle in Mainland China), which did not develop vesicular lesions under field conditions. Five viruses isolates obtained from individual farms were confirmed to be the serotype O FMD virus (O/Taiwan/1999). During January-February 2000, however, this virus has spread to dairy cattle and goat herds, causing severe mortality in goat kids and vesicular lesions in dairy cattle. Partial nucleotide sequence of the capsid coding gene 1D (VP1) was determined for the virus isolates obtained in this study. Phylogenetic analysis of the VP1 sequences indicated that the O/Taiwan/1999 viruses shared 95-97% similarities to the virus strains isolated from the Middle East and India. The species susceptibility of the O/Taiwan/1999 virus was experimentally studied in several species of susceptible animals, showing that the virus did cause generalized lesions in dairy cattle and pigs, however, it would not cause vesicular lesions on the Chinese yellow cattle and the adult goats. These studies suggested that the O/Taiwan/1999 virus was a novel FMD virus of Taiwan and it presented various levels of susceptibility in cattle species.
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Su CM, Liao CL, Lee YL, Lin YL. Highly sulfated forms of heparin sulfate are involved in japanese encephalitis virus infection. Virology 2001; 286:206-15. [PMID: 11448173 DOI: 10.1006/viro.2001.0986] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Japanese encephalitis virus (JEV) infects a broad range of cell types in vitro, though little is known about the initial events of JEV infection. In the present study, we found that highly sulfated glycosaminoglycans (GAGs) are involved in infection of both neurovirulent (RP-9) and attenuated (RP-2ms) JEV strains. Competition experiments using highly sulfated GAGs, heparin and dextran sulfate, demonstrated an inhibition of JEV's attachment and subsequent infection of BHK-21 cells. Treatment of target cells by a potent sulfation inhibitor, sodium chlorate, greatly reduced viral binding ability as well as infection, suggesting a critical role of GAGs' sulfation status on the cellular surface in JEV infection. This phenomenon was confirmed by the manifestation of a distinct binding efficiency of JEV to the wild-type CHO cell line and its mutants with defects in GAG biosynthesis. We also demonstrated the binding of JEV particles and virus envelope glycoprotein to immobilized heparin beads. Furthermore, the addition of heparin suppressed the cytopathic effects induced by JEV infection in cultured cells. Our results establish that the highly sulfated form of GAGs on cell surfaces plays a determining role in the early stage of in vitro JEV infection.
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Hung MW, Tsai LC, Lin YL, Chen YH, Chang GG, Chang TC. Differential regulation of placental and germ cell alkaline phosphatases by glucocorticoid and sodium butyrate in human gastric carcinoma cell line TMK-1. Arch Biochem Biophys 2001; 388:45-54. [PMID: 11361139 DOI: 10.1006/abbi.2001.2276] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The expression and regulation of alkaline phosphatase (AP) was studied in the human gastric cancer cell line TMK-1. Biochemical analysis, reverse transcription-polymerase chain reaction, and Northern blot analysis demonstrated that the cells express placental, germ cell, and intestinal AP isozymes constitutively. Dexamethasone (Dex), a synthetic glucocorticoid, was shown to specifically induce the placental AP activity to about 10-fold and sodium butyrate (NaBu) induced germ cell AP activity to about 4-fold, respectively. In contrast, these two agents showed little effect on the level of intestinal isozymes. Dex and NaBu also differentially induced the mRNA levels of the placental and germ cell APs. Northern blot analysis of the placental AP transcript in the presence of the transcription inhibitor, 5, 6-dichloro-1-beta-D-ribofuranosyl benzimidazole, revealed that the half-life of placental AP mRNA is about 27 h for both the Dex-treated and untreated cells. Nuclear run-on transcription analysis indicated an apparent increase in the rate of placental AP gene transcription in Dex-treated cells. These results indicated that the effect of Dex occurred primarily by activation of the placental AP gene transcription in the cells. In order to study the direct Dex and NaBu effect on AP gene expression, the proximal promoter regions of AP genes were fused to luciferase reporter vectors. Despite the high similarity in nucleotide sequences of these two genes, transient transfection analysis demonstrated that Dex and NaBu exerted a specific stimulation only through the respective placental and germ cell AP gene promoter. Taken together, this study indicates that the expression of PAP and GCAP isozymes have specific regulatory mechanisms that can be differentially controlled by signals including glucocorticoid and NaBu.
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Liu HC, Chen RM, Jian WC, Lin YL. Cytotoxic and antioxidant effects of the water extract of the traditional Chinese herb gusuibu (Drynaria fortunei) on rat osteoblasts. J Formos Med Assoc 2001; 100:383-8. [PMID: 11480247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
BACKGROUND AND PURPOSE Gusuibu (Drynaria fortunei) is a traditional Chinese herb that has been claimed to have therapeutic effects on bone healing; however, a clinical mechanism responsible for this effect has not been identified. This study evaluated the cytotoxic and antioxidant effects of the water extract of gusuibu (WEGSB) on rat osteoblasts. MATERIALS AND METHODS Osteoblasts were prepared from neonatal Wistar rat calvarias and treated with WEGSB. Cell viability and alkaline phosphatase activity were determined. Intracellular reactive oxygen species were detected using the dye 2',7'-dichlorofluorescin, and mitochondrial membrane potential was detected using the dye 3,3'-dihexyloxacarbocyanine iodide and flow cytometry. RESULTS WEGSB at 1 and 10 micrograms/mL was not cytotoxic to rat osteoblasts, but WEGSB at 100 micrograms/mL reduced cell viability and alkaline phosphatase activity in a time-dependent manner. Although WEGSB and hydrogen peroxide did not affect the mitochondrial membrane potential of rat osteoblasts, combined treatment with WEGSB (100 micrograms/mL) and hydrogen peroxide lowered the membrane potential of mitochondria and resulted in cell death. The basal level of intracellular reactive oxygen species in rat osteoblasts was significantly suppressed by WEGSB at 10 to 100 micrograms/mL. WEGSB (10 micrograms/mL) specifically inhibited hydrogen peroxide-induced oxidative stress without an effect on nitric oxide-induced stress. Hydrogen peroxide caused concentration-dependent death of rat osteoblasts, but WEGSB significantly protected cells from hydrogen peroxide-induced death. CONCLUSION This study has shown that WEGSB at 10 micrograms/mL is not cytotoxic to rat osteoblasts in vitro, and also that the extract at 10 micrograms/microL has an antioxidant effect on these cells. The antioxidant activity of WEGSB can protect rat osteoblasts from hydrogen peroxide-induced death and may promote bone recovery under similar pathologic conditions.
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Lin YL, Dutta A. In vitro analysis of SV40 DNA replication. CURRENT PROTOCOLS IN CELL BIOLOGY 2001; Chapter 11:Unit 11.5. [PMID: 18228310 DOI: 10.1002/0471143030.cb1105s02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This unit describes a method for studying cellular factors that affect eukaryotic replication by using a plasmid that contains an SV40 origin of replication and supplying the viral helicase T antigen. Replication factors are supplied by S100 extracts of 293 cells. The unit also contains protocols for expression and purification of T antigen and analysis of the products of replication.
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Ko WC, Lei CB, Lin YL, Chen CF. Mechanisms of relaxant action of S-petasin and S-isopetasin, sesquiterpenes of Petasites formosanus, in isolated guinea pig trachea. PLANTA MEDICA 2001; 67:224-229. [PMID: 11345692 DOI: 10.1055/s-2001-11991] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We investigated the mechanisms of action of S-petasin and S-isopetasin, from Petasites formosanus Kitamura which is used as a folk medicine for treating hypertension, tumors, and asthma in Taiwan. The tension changes of tracheal segments were isometrically recorded on a polygraph. S-Petasin and S-isopetasin non-competitively inhibited cumulative histamine-, and carbachol-induced contractions with an exception that S-isopetasin produced a parallel, rightward shift of the concentration-response curve of carbachol in a competitive manner. S-Petasin also non-competitively inhibited cumulative Ca(2+)-induced contractions in depolarized (K+, 60 mM; histamine, 100 microM; or carbachol, 10 microM) guinea-pig tracheas. S-Isopetasin did in depolarized (K+, 60 mM) trachea too. The nifedipine (10 microM)-remaining tension of carbachol (0.2 microM)-induced precontraction was further relaxed by S-petasin or S-isopetasin, suggesting that no matter whether either blocked VDCCs or not, S-petasin or S-isopetasin may have other mechanisms of relaxant action. The relaxant effect of S-petasin or S-isopetasin was unaffected by the presence of propranolol (1 microM), 2',5'-dideoxyadenosine (10 microM), methylene blue (25 microM), glibenclamide (10 microM), N omega-nitro-L-arginine (20 microM), or alpha-chymotrypsin (1 U/ml). However, S-petasin (100-300 microM), but not S-isopetasin, significantly inhibited cAMP-, but not cGMP-dependent PDE activity of the trachealis. The above results reveal that the mechanisms of relaxant action of S-petasin and S-isopetasin may be primarily due to its non-specific antispasmodic and antimuscarinic effects, respectively.
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