37 research outputs found

    Effect of Copper Acyclovir Complexes on Herpes Simplex Virus Type 1 and Type 2 (HSV-1, HSV-2) Infection in Cultured Cells

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    We have found that when copper, zinc or cobalt is bound to a suitable ligand, the appropriate complex exhibited a significant anti-HSV effect (Varadinova et al., 1993; 1996). Recently published data by Sagripanti et al. (1997) also show that the inhibition of HSV by copper was enhanced by reducing agents and that mechanism of the inactivation is similar as for copper-mediated DNA damage (Aruoma, et al. 1991; Dizdaroglu, et al., 1991; Toyokuni and Sagripanti, 1994). Therefore it was interesting to study the efect of Cu(ll) coordination compounds with acyclovir (ACV) on the replication of HSV in cultured cells. The experiments on cytotoxicity as well as on the activity of three different Cu-ACV complexes [Cu(ACV)2Cl2(H2O)2] = (A); [Cu(ACV)2(H2O)3](NO3)2.H2O = (B) and [Cu(ACV)2(H2O)2](NO3)2] = (C) towards virus replication, with special attention on the growth of ACV-resistant strain R-100 were performed on MDBK cells. ACV was used as a reference compound. The following results were obtained: 1) Increased cell’s viability in the presence of 20-40(g/ml ACV and decreased one in the presence of Cu-ACV complexes with relative level (A) >> (B) > (C); 2) Cu-ACV complexes are more cytotoxic than the ligand - ACV and the relative level is (C)>(B)>(A); 3) The anti-HSV effect of ACV can be modulated by copper at levels depending on the specificity of the particular virus strain: (i) for the ACV sensitive strain DA (HSV-1) - ACV ((A) > (C) > (B); (ii) for the ACV sensitive strain Bja (HSV-2) (A) > ACV > (C) > (B); (iii) for strain R-100 (ACVR, TKa) - (A) > ACV > (C) > (B). This findings are consistent with previously published data and undoubtedly show that Cu-ACV complexes could be useful in the treatment of HSV infections, especially when the causative agent is a resistant to ACV mutant

    Effect of Complexes of Zinc, Cobalt and Copper With D-Aminosugars on the Replication of Herpes Simplex Virus Type 1 (HSV-1)

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    Our previous results show that Zn(pic)2 and Zn(asp)2 inhibit key steps of the replication of HSV-1. Anti-HSV effect of complexes of Co(II) with aminoacids Lys and Ser was also found. In the present study we describe the effect of complexes of Zn(II), Co(II) and Cu(II) with D-aminosugars on the replication of HSV-1 and on the infectivity of free virions. The experiments were done using primary rabbit kidney cells (r.k.), diploid human embryonal fibroblasts (F) and Vero cells. No differences in the toxicity of metal complexes on diploid cells- r.k. and F, were found. Neither metal complexes, nor ligands-galactosoxime and glucosoxime, influenced the viral replication. During 1-4h prolonged contact only Cu(Gl.NOH)2 inactivated HSV-1 virions up to 90%. The results show that D-aminosugars are not suitable ligands for Zn(II), Cu(II) and Co(II) in respect of the inhibition of viral replication. However, only Cu(Gl.NOH)2 was able to inhibit the infectivity of free virions

    Effect of Complexes of Cobalt With Aminoacids on the Replication of Herpes Simplex Virus Type 1 (HSV-1)

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    Cobalt, being essential metal, influences different physiological and enzymatic functions. As cobalt does not accumulate in the body, Co-compounds have relatively low toxicity. The aim of the present study is the effect of complexes of Co(II) with aminoacids - lysine, arginine, histidine and serine on HSV-1 replication. No effect of [O2Co(his)4].nH2O and [O2Co(arg)2].nH2O on HSV-1 infection in vitro was found. Both, [O2Co(lys)2].nH2O and [O2Co(ser)2].nH2O suppress the attachement of HSV-1 particles onto target cells and the viral replication as well. Moreover, the properties of the particular Co-complex (charge, stability, structure) are manifestated by their virucidal effect. Thus, [O2Co(ser)2].nH2O irreversibly inhibits the infectious activity of free HSV-1 virions, while virucidal effect of [O2Co(lys)2].nH2O is completely reversible after the 2h of contact

    Platinum(II) and Palladium(II) Complexes of Pyridine-2-Carbaldehyde Thiosemicarbazone as Alternative Antiherpes Simplex Virus Agents

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    The cytotoxicity and the antivirus activity of Pd(II) and Pt(II) complexes with pyridine-2-carbaldehyde thiosemicarbazone (HFoTsc) against HSV replication were evaluated on four HSV strains—two wt strains Victoria (HSV-1) and BJA (HSV-2) and two ACVR mutants with different tk gene mutations R-100 (TKA, HSV-1) and PU (TKN, HSV-2). The experiments were performed on continuous MDBK cells and four HSV 1 and HSV 2 strains were used, two sensitive to acyclovir and two resistant mutants. The five complexes of HFoTsc, [Pt(FoTsc)Cl], [Pt(FoTsc)(H2FoTsc)]Cl2, [Pt(FoTsc)2], [Pd(FoTsc)(H2FoTsc)]Cl2, and [Pd(FoTsc)2], were found to be effective inhibitors of HSV replication. The most promising, active, and selective anti-HSV agent was found to be complex [Pt(FoTsc)(H2FoTsc)]Cl2. This complex could be useful in the treatment of HSV infections, since it is resistant to ACV mutants. PCR study of immediate early 300 bp ReIV Us1 region reveals that the complex [Pt(FoTsc)(H2FoTsc)]Cl2 specifically suppressed wt HSV-1 genome 2 hours after the infection, not inducing apoptosis/necrosis on the 8 hours after virus infection. The target was found to be most probably the viral, instead of the host cell DNA

    Selectivity of a thiosemicarbazonatocopper(II) complex towards duplex RNA. Relevant noncovalent interactions both in solid state and solution

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    Thiosemicarbazones and their metal derivatives have long been screened as antitumor agents, and their interactions with DNA have been analysed. Herein, we describe the synthesis and characterization of compounds containing [CuL]+ entities (HL = pyridine-2-carbaldehyde thiosemicarbazone) and adenine, cytosine or 9-methylguanine, and some of their corresponding nucleotides. For the first time, crystal structures of adenine- and 9-methylguanine-containing thiosemicarbazone complexes are reported. To the best of our knowledge, the first study on the affinity thiosemicarbazone–RNA is also provided here. Experimental and computational studies have shown that [CuL(OH2)]+ entities at low concentration intercalate into dsRNA poly(rA)·poly(rU) through strong hydrogen bonds involving uracil residues and π–π stacking interactions. In fact, noncovalent interactions are present both in the solid state and in solution. This behaviour diverges from that observed with DNA duplexes and creates an optimistic outlook in achieving selective binding to RNA for subsequent possible medical applications.Obra Social “la Caixa” (OSLC-2012-007), Ministerio de EconomĂ­a y Competitividad and FEDER funds (CTQ2013-48937-C2-1-P, CTQ2015-70371- REDT, MAT2012-34740 and CTQ2014-58812-C2-2-R), Junta de Castilla y LeĂłn (BU237U13), the Basque Government (IT-779- 13), Gerencia Regional de Salud, ConsejerĂ­a de Sanidad, Junta de Castilla y LeĂłn (GRS 1023/A/14 and GR172)

    The recovery of European freshwater biodiversity has come to a halt

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    Owing to a long history of anthropogenic pressures, freshwater ecosystems are among the most vulnerable to biodiversity loss1. Mitigation measures, including wastewater treatment and hydromorphological restoration, have aimed to improve environmental quality and foster the recovery of freshwater biodiversity2. Here, using 1,816 time series of freshwater invertebrate communities collected across 22 European countries between 1968 and 2020, we quantified temporal trends in taxonomic and functional diversity and their responses to environmental pressures and gradients. We observed overall increases in taxon richness (0.73% per year), functional richness (2.4% per year) and abundance (1.17% per year). However, these increases primarily occurred before the 2010s, and have since plateaued. Freshwater communities downstream of dams, urban areas and cropland were less likely to experience recovery. Communities at sites with faster rates of warming had fewer gains in taxon richness, functional richness and abundance. Although biodiversity gains in the 1990s and 2000s probably reflect the effectiveness of water-quality improvements and restoration projects, the decelerating trajectory in the 2010s suggests that the current measures offer diminishing returns. Given new and persistent pressures on freshwater ecosystems, including emerging pollutants, climate change and the spread of invasive species, we call for additional mitigation to revive the recovery of freshwater biodiversity.N. Kaffenberger helped with initial data compilation. Funding for authors and data collection and processing was provided by the EU Horizon 2020 project eLTER PLUS (grant agreement no. 871128); the German Federal Ministry of Education and Research (BMBF; 033W034A); the German Research Foundation (DFG FZT 118, 202548816); Czech Republic project no. P505-20-17305S; the Leibniz Competition (J45/2018, P74/2018); the Spanish Ministerio de EconomĂ­a, Industria y Competitividad—Agencia Estatal de InvestigaciĂłn and the European Regional Development Fund (MECODISPER project CTM 2017-89295-P); RamĂłn y Cajal contracts and the project funded by the Spanish Ministry of Science and Innovation (RYC2019-027446-I, RYC2020-029829-I, PID2020-115830GB-100); the Danish Environment Agency; the Norwegian Environment Agency; SOMINCOR—Lundin mining & FCT—Fundação para a CiĂȘncia e Tecnologia, Portugal; the Swedish University of Agricultural Sciences; the Swiss National Science Foundation (grant PP00P3_179089); the EU LIFE programme (DIVAQUA project, LIFE18 NAT/ES/000121); the UK Natural Environment Research Council (GLiTRS project NE/V006886/1 and NE/R016429/1 as part of the UK-SCAPE programme); the Autonomous Province of Bolzano (Italy); and the Estonian Research Council (grant no. PRG1266), Estonian National Program ‘Humanitarian and natural science collections’. The Environment Agency of England, the Scottish Environmental Protection Agency and Natural Resources Wales provided publicly available data. We acknowledge the members of the Flanders Environment Agency for providing data. This article is a contribution of the Alliance for Freshwater Life (www.allianceforfreshwaterlife.org).Peer reviewe

    An Investigation of the Extended Storage of Single-base Propellants

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    An investigation of single-base propellants has been conducted. The ageing process during extended storage of single-base propellants (SBP) in nonheated military stores and a heated building has been investigated by elemental analysis. Two or three different absorbencies around the band at 1650 cm-1 were observed by FTIR spectroscopy. In this way, not only the denitration of the propellants was determined, but also cleavage of -O-C- bonds between the glycoside rings in the nitrocellulose macromolecules. The latter process was confirmed by the swelling of the SBP
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