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Virus Activity (virus + activity)
Selected AbstractsSynthesis and in vitro Antihepatitis B and C Virus Activities of Ring-Expanded ("Fat") Nucleobase Analogues Containing the Imidazo[4,5-e][1,3]diazepine-4,8-dione Ring System.CHEMINFORM, Issue 11 2006Peng Zhang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis and In-Vitro Anti-Hepatitis-B Virus Activity of 6H -[1]Benzothiopyrano[4,3- b] quinolin-10-olsARCHIV DER PHARMAZIE, Issue 9 2009Wei Jia Abstract A series of 9-methoxy-6H -[1]benzothiopyrano[4,3- b]quinolin-10-ols with a Mannich side chain were synthesized and evaluated for their anti-Hepatitis B virus (HBV) activity in HepG2.2.15 cells. Some compounds showed significant anti-HBV activity with IC50 values less than 41 ,M. Among them, compound 9b was the most effective anti-HBV agent (IC50 = 1.7 ,M, SI = 60.3). [source] Synthesis and anti-Measles Virus Activity of New Isoquinolin-4-one Derivatives.CHEMINFORM, Issue 13 2004N. A. Santagati No abstract is available for this article. [source] Alkaloids from Corydalis saxicola and Their Anti-Hepatitis B Virus ActivityCHEMISTRY & BIODIVERSITY, Issue 5 2008Hui-Liang Li Abstract Eight protoberberine-type alkaloids and two indole alkaloids were isolated from the MeOH extracts of the herb Corydalis saxicolaBunting (Papaveraceae). Their structures were identified as dehydrocavidine (1), dehydroapocavidine (2), dehydroisoapocavidine (3), berberine (4), dehydroisocorypalmine (5), coptisine (6), tetradehydroscoulerine (7), berbinium (8), 1-formyl-5-methoxy-6-methylindoline (9), and 1-formyl-2-hydroxy-5-methoxy-6-methylindoline (10). Compounds 3, 9, and 10 are new alkaloids. All compounds were tested for anti-HBV activity against the 2.2.15 cell line in vitro. Dehydrocavidine (1), dehydroapocavidine (2), and dehydroisoapocavidine (3) exhibited inhibitory activity against HBsAg and HBeAg, but no cytotoxicity against the 2.2.15 cell line. [source] Role of ISGF3 in modulating the anti-hepatitis B virus activity of interferon-alpha in vitroJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 11 2008Quan Zhang Abstract Background and Aim:, Although interferon-, (IFN-,) is an effective treatment for hepatitis B virus (HBV) infection, its precise mechanism of action has not been identified. In this study, we investigated the role of signal transduction pathways in the activation of anti-HBV responses mediated by IFN-,. Methods:, Using an oligo microarray, we found that four genes in the IFN-, signal pathway were markedly upregulated by IFN-, in human hepatoma cells regardless of whether they had been transfected with a plasmid containing the HBV genome: signal transducers and activators of transcription 1 (STAT1), interferon regulatory factor-9 (IRF-9, also called ISGF3, or P48), IFN-,-inducible protein 15 (IFI-15) and IFN-,-inducible protein 6,16 (IFI-6-16). We also investigated the role of IFN-stimulated gene factor3 (ISGF3) complex in IFN-,-mediated anti-HBV responses in human hepatoma cells by measuring the mRNA of the three genes within ISGF3 (STAT1, STAT2 and IRF-9) using semiquantitative reverse-transcription PCR (RT-PCR), and expression of the three proteins by western blot, and the mRNA and protein of dsRNA-dependent protein kinase (PKR). Results:, STAT1, STAT2, IRF-9 and PKR mRNA as well as protein levels were upregulated by IFN-, treatment. When cells were pretreated with genistein, STAT1, STAT2 and IRF-9 mRNA levels remained unchanged after IFN-, stimulation, but PKR mRNA levels decreased, and the expression of the STAT1, P-STAT2, IRF-9 and PKR proteins decreased. Levels of HBV DNA decreased in the supernatants of cells treated with IFN-,, while ISGF3 levels increased. The quantity of HBV DNA remained unchanged by pretreating with genistein. Conclusions:, These observations suggested that the Janus tyrosine kinase,STAT (JAK-STAT) pathway may play a major role in mediating the effects of IFN-, against HBV, and that ISGF3 might be a key factor. [source] Effects of Clinacanthus siamensis leaf extract on influenza virus infectionMICROBIOLOGY AND IMMUNOLOGY, Issue 2 2009Mali Wirotesangthong ABSTRACT Ethanolic extracts of 20 medicinal plants were screened for influenza virus NA inhibition and in vitro antiviral activities using MDCK cells in an MTT assay. The vaccine proteins of influenza virus A/New Caledonia/20/99 (H1N1), mouse-adapted influenza virus A/Guizhou/54/89 (A/G)(H3N2) and mouse-adapted influenza virus B/Ibaraki/2/85 (B/I) were used in the NA inhibition assay, and mouse-adapted influenza viruses A/PR/8/34 (H1N1), A/G and B/I were used in the in vitro antiviral assay. The results of the in vitro antiviral assay indicated that the A/G virus was the most susceptible and an extract of the leaf of CS possessed the highest in vitro anti-A/G virus activity (41.98%). Therefore, the A/G virus and the CS extract were selected for studying in vivo anti-influenza virus activity. BALB/c mice were treated with CS extract (100 mg/kg per day, 5 times) orally from 4 hr before to 4 days after infection. CS extract elicited significant production of anti-influenza virus IgG1 antibody in BAW and increased mouse weight compared to oseltamivir (0.1 mg/kg per day) on day 19 or water on days 17,19 of infection. Moreover, CS extract produced a higher anti-influenza virus IgA antibody level in BAW compared to oseltamivir, and a tendency towards an increase in anti-influenza virus IgA compared to water was shown. The results suggest that CS extract has a protective effect against influenza virus infection. [source] Anti-influenza virus activity of crude extract of Ribes nigrum L.PHYTOTHERAPY RESEARCH, Issue 2 2003Yoko M. Knox Abstract This experiment was designed to detect the antiviral activities of crude fruit extracts of wild Ribes nigrum L. (Kurokarin extract) against influenza virus types A and B. Kurokarin extract was prepared as follows: fruits of Ribes nigrum L. were heated at 50,°C in a heating tank, and then ground under anaerobic conditions. The extracts were centrifuged, and the supernatant fluid was filtered and sterilized by infrared rays. The crude extract was diluted with Eagle's minimum essential medium (MEM) and the solution was adjusted to a pH 7.2 with 0.1 N or 1 N NaOH. Proven anti-influenza virus effects of the extracts were shown. The concentration of extract required to inhibit the plaque formation of both IVA and IVB by 50% (IC50) was 3.2,,g/mL. Both IVA and IVB were directly inactivated up to 99% by 10,,g/mL of the extract at pH 2.8, and 95% to 98% by this dose at pH 7.2. The growth of IVA in cells treated with 10 and 100,,g/mL of the extract for 6,h after infection was completely suppressed. Virus titres in culture fluids of the cells treated with 100,,g/mL of Kurokarin extract for 1,h at 8 to 9,h after infection, were completely suppressed, indicating that the extract inhibited the virus release from the infected cells. Copyright © 2003 John Wiley & Sons, Ltd. [source] ORIGINAL ARTICLE: Female Genital Tract Secretions Inhibit Herpes Simplex Virus Infection: Correlation with Soluble Mucosal Immune Mediators and Impact of Hormonal ContraceptionAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010Gail F. Shust Citation Shust GF, Cho S, Kim M, Madan RP, Guzman EM, Pollack M, Epstein J, Cohen HW, Keller MJ, Herold BC. Female genital tract secretions inhibit herpes simplex virus infection: correlation with soluble mucosal immune mediators and impact of hormonal contraception. Am J Reprod Immunol 2010; 63: 110,119 Problem, Female genital tract secretions inhibit herpes simplex virus (HSV) infection, however, the intra- and inter-subject variability, contribution of specific mediators, and impact of reproductive hormones have not been defined. Method of study, Cervicovaginal lavage (CVL) (n = 89) obtained from nine cyclers and seven women on hormonal contraception (HC), who completed between three and eight weekly visits, were examined for anti-herpes simplex virus activity and concentrations of mediators. Results, The CVL inhibited HSV infection by a mean value of approximately 57% during the follicular or luteal phase, but only by 36% in hormonal contraceptive users. Human neutrophil peptides 1,3 (HNP1-3) (P = 0.03), IL-8 (P = 0.003), lactoferrin (P = 0.005), lysozyme (P = 0.003), IgA (P = 0.002), and IgG (P = 0.02) correlated with antiviral activity. Intra-subject and inter-subject variability was observed, suggesting that factors other than hormones contribute to innate defense. Conclusion, Endogenous antimicrobial activity may provide a biomarker of healthy mucosal immunity and may be reduced in the setting of HC. However, larger prospective studies are needed. [source] Environmental and entomological factors determining Ross River virus activity in the River Murray Valley of South AustraliaAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 3 2009Craig R. Williams Abstract Objectives: 1) To determine whether environmental and mosquito abundance variables could be used to explain fluctuations in the activity of Ross River (RR) virus, in the River Murray Valley of South Australia (SA). 2) To develop models at the local government spatial scale to understand local variability in RR activity factors. Method: Notification data of RR virus positive serology, mosquito surveillance, meteorological and river height data were analysed for the period 1999 to 2006. Stepwise multiple regression was used to determine significant environmental factors and to create descriptive models. Results: The three models developed for different regions of the Valley explained significant amounts of variation in notification rates (R2 0.77 , 0.98). Regional variation in the models was observed, with differences in significant mosquito species evident. Rainfall was a significant predictor of RR virus activity in two of the models, while the height of the River Murray was significant in the third. An overall model for the entire SA section of the Valley contained only time-lagged mosquito abundance variables (R2 0.52). Conclusion: Although rainfall, river height and mosquito abundance are significant factors in determining RR virus activity, there are regional differences in this relationship. Implications: The regional variability of RR virus activity drivers has been defined, and has implications for the forecasting of future activity in this part of SA. The models provided here can provide the foundation for an effective RR virus early warning system, but only if criteria for action, lines of responsibility and the resources required have been determined. [source] Prediction of Activity, Synthesis and Biological Testing of anti-HSV Active PeptidesCHEMICAL BIOLOGY & DRUG DESIGN, Issue 1 2006Håvard Jenssen Herpes simplex virus infections can be treated with a number of drugs, but as for all pathogens, there is a constant need for new therapies. In the search for lead compounds some peptides have proven to possess an antiviral effect, but it is still unclear what mechanisms are responsible for this effect. We wish to report on the use of principal properties of amino acids for developing quantitative structure,activity relationships (QSAR:s) as a tool for modelling peptide activity and predicting the activity of new peptides. In order to test the reliability of the method, new peptides have been designed by using multivariate methodology, synthesized and tested for a number of responses. Two of the new peptides synthesized were active at lower concentrations than experienced before regarding entry and herpes simplex virus activity, but they were not able to completely inhibit viral infection. This may reflect differences in mode of action of peptides depending on the amino acid content. [source] | ||||||||||||||||