title: [Anti-herpes simplex virus action of combined therapy with cyclocytidine and ganciclovir].
abstract: OBJECTIVE
  The study was designed to investigate the combined effect of cyclocytidine (CC) and ganciclovir (GCV) on herpes simplex virus-1 (HSV-1) in cell culture.
  
  
  METHODS
  The 50% inhibition concentrations of HSV-1 plaque formation (IC50) of CC, GCV alone and in combination were determined by the inhibitory test of plaque formation. The combined anti-HSV-1 effect of CC and GCV was evaluated by a graphic method and fractional inhibitory concentration (FIC) indexes.
  
  
  RESULTS
  IC50 of CC and GCV was 0.19 and 0.1 micrograms/ml, respectively. The combination of CC with GCV produced significantly synergistic activity against HSV-1 in cell culture. FIC indexes were all below 0.75. The combined therapy of CC and GCV can also decrease and delay the emergence of drug-resistant variants.
  
  
  CONCLUSIONS
  These results suggest that this combined therapy of CC and GCV may be a potentially effective means in the management of patients with HSV-1 ocular infection.
authors: Henan Institute of Ophthalmology, Zhengzhou.
authors: Z
authors: Z
authors: Chen
authors: J
authors: J
authors: Song
authors: K
authors: K
authors: Chen
mesh_terms: D003504:Ancitabine / Q000494:pharmacology*; D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology*; D002522:Chlorocebus aethiops; D004357:Drug Synergism; D015774:Ganciclovir / Q000494:pharmacology*; D018259:Herpesvirus 1, Human / Q000187:drug effects* / Q000254:growth & development; D006801:Humans; D014709:Vero Cells; D010948:Viral Plaque Assay
chemical_list: D000998:Antiviral Agents; D003504:Ancitabine; D015774:Ganciclovir