The in vitro anti-herpes simplex virus type-1 and type-2 activity of Long Dan Xie Gan Tan, a prescription of traditional Chinese medicine.
ABSTRACT Long Dan Xie Gan Tan (LDXGT), a decoction of radix gentianae for purging the pathogenic inflammation of the liver, is a widely used prescription among many in traditional Chinese medicine. The prescription is primarily used to treat the disorders induced by damp-heat in the liver and the gall bladder.
In this study, the in vitro anti-herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2) activity of the water extract of LDXGT was investigated.
LDXGT water extract was shown to exhibit anti-HSV activity. The IC(50) values of LDXGT against HSV-1 and HSV-2 infections were 257.5 +/- 12.2 and 494.6 +/- 1.8 microg/ml, respectively. It had a CC(50) value of 4,077.2 +/- 2.4 microg/ml towards Vero cells and showed no cytotoxic effect at a concentration of 2,000 microg/ml or below. The prescription was also found to inactivate HSV-2 infectivity in a dose-, time- and temperature-dependent manner.
In summary, the water extract of LDXGT was concluded to inhibit HSV-1 and HSV-2 infection at different magnitudes of potency, and our observations also suggested that the effect was likely mediated by directly inactivating the virus infectivity.
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ABSTRACT: Acyclovir (ACV) has been used for more than 15 years in the management of herpes simplex virus (HSV) and varicella-zoster virus (VZV) disease. The present survey was undertaken to assess the level of ACV resistance in the population. More than 2,000 HSV isolates from both immunocompetent and immunocompromised patients in northwest England were collected over a 2-year period and tested for sensitivity to ACV. These studies suggested a prevalence of resistance of approximately 0.1 to 0.6% in immunocompetent individuals, with no apparent difference in prevalence between treated and untreated groups. In line with previous studies, the prevalence of resistance in treated immunocompromised individuals was approximately 6%.Antimicrobial Agents and Chemotherapy 05/1998; 42(4):868-72. · 4.57 Impact Factor
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ABSTRACT: In early trials of antiretroviral therapy, acyclovir was associated with increased survival by an unknown mechanism. The hypothesis that subclinical herpes simplex virus (HSV) reactivation was associated, in vivo, with increased plasma human immunodeficiency virus (HIV) RNA and suppression with a reduced plasma HIV RNA load was investigated. HSV cultures were performed daily on HSV-2-positive/HIV-positive patients, and plasma HIV-1 RNA loads were measured at regular intervals. A subset of patients prior to, during, and after HSV suppression with high-dose acyclovir was measured to determine whether HSV suppression was associated with a decrease in HIV replication. Most (25/27 HSV-2-positive/HIV-positive persons) reactivated HSV. Total HSV shedding rate was strongly correlated with plasma HIV-1 RNA load (R=0.54; P=.004), and the plasma HIV-1 RNA level at a given CD4 cell count was 48% lower when treated with acyclovir. These data indicate that frequent mucosal HSV reactivation influences HIV replication in vivo and daily HSV suppression may be important in the management of HSV-positive/HIV-positive persons.The Journal of Infectious Diseases 01/2003; 186(12):1718-25. · 5.85 Impact Factor
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ABSTRACT: For the past 2 years, a survey network was established for the screening of acyclovir (ACV)-resistant clinical isolates of herpes simplex virus (HSV). Among 889 strains tested for in vitro ACV sensitivity, 14 HSV-1 and 6 HSV-2 were resistant to ACV concentrations exceeding 3 micrograms/ml. These resistant isolates were most often obtained after prolonged ACV treatment of severely immunocompromised patients. For five patients, the emergence of ACV-resistant virus correlated with treatment failure. In particular, a decrease in the in vitro sensitivity to ACV was observed for eight successive HSV-1 isolates from one immunodeficient patient undergoing therapy. All ACV-resistant isolates were studied for their sensitivity to different antiherpetic compounds and showed various cross-sensitive and -resistant patterns. The examination of viral populations by plaque autoradiography procedures frequently revealed their heterogeneity in terms of thymidine kinase (TK) phenotype and allowed the detection of various proportions of TK-positive (TK+), TK-deficient (TKD), or TK-altered (TKA) viruses. Our data underline the importance of monitoring the emergence of drug-resistant virus during the course of antiviral therapy, and the need for the detection and characterization of TK mutants in clinical specimens. The routine examination of drug sensitivity of HSV isolates provides useful information to clinicians for the management of ACV treatment in the hope of preventing ACV-resistant mutants from becoming predominant in mixed viral populations.Journal of Medical Virology 02/1992; 36(1):1-12. · 2.37 Impact Factor