ST-246 is a low-molecular-weight compound (molecular weight‫؍‬Recent concerns over the use of variola (smallpox) virus as a biological weapon have prompted renewed interest in development of small molecule therapeutics that target variola virus replication. Currently, there is no U.S. Food and Drug Administration-approved drug for the prevention or treatment of smallpox infection. While a number of compounds have been shown to inhibit orthopoxvirus replication in vitro, these compounds often lack potency and/or are associated with significant adverse effects, due to their relative nonspecific mechanisms of virus inhibition (3).The cornerstone of the current national public health response plan to a smallpox bioterrorist attack calls for rapid mass immunization with vaccinia virus. However, concerns about vaccine-related adverse events have compromised implementation of a smallpox immunization program. Individuals with immunodeficiency disorders or certain common skin conditions are unusually susceptible to vaccine-related complications (6, 32). Moreover, the lag period for antibody formation from a vaccine leaves a window of vulnerability. Antiviral therapies can fill this void and provide an excellent complement to vaccination in that they reduce virus titers quickly, regardless of immune status, and lower transmission rates by diminishing the virus reservoir. A small-molecule antiviral drug designed to treat variola virus infection will be a critical component to a smallpox defense strategy.Currently, only cidofovir [CDV; (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine; Vistide], a drug approved for treatment of cytomegalovirus (CMV) retinitis in AIDS pa-* Corresponding author. Mailing address:

Dengue virus (DENV) is the predominant mosquito-borne viral pathogen that infects humans with an estimated 50 to 100 million infections per year worldwide. Over the past 50 years, the incidence of dengue disease has increased dramatically and the virus is now endemic in more than 100 countries. Moreover, multiple serotypes of DENV are now found in the same geographic region, increasing the likelihood of more severe forms of disease. Despite extensive research, there are still no approved vaccines or therapeutics commercially available to treat DENV infection. Here we report the results of a high-throughput screen of a chemical compound library using a whole-virus assay that identified a novel small-molecule inhibitor of DENV, ST-610, that potently and selectively inhibits all four serotypes of DENV replication in vitro. Sequence analysis of drug-resistant virus isolates has identified a single point mutation, A263T, in the NS3 helicase domain that confers resistance to this compound. ST-610 inhibits DENV NS3 helicase RNA unwinding activity in a molecular-beacon-based helicase assay but does not inhibit nucleoside triphosphatase activity based on a malachite green ATPase assay. ST-610 is nonmutagenic, is well tolerated (nontoxic) in mice, and has shown efficacy in a sublethal murine model of DENV infection with the ability to significantly reduce viremia and viral load compared to vehicle controls.

Background: Proteins associated with the late endosome (LE) appear to play a central role in the envelopment of a number of taxonomically diverse viruses. How viral proteins interact with LEassociated proteins to facilitate envelopment is not well understood. LE-derived transport vesicles form through the interaction of Rab9 GTPase with cargo proteins, and TIP47, a Rab9-specific effector protein. Vaccinia virus (VV) induces a wrapping complex derived from intracellular host membranes to envelope intracellular mature virus particles producing egress-competent forms of virus.

This study provides useful epidemiological information on cervical HPV infection prevalence in general female population from Guangdong Province, China. In this population, HPV infection prevalence was 7.3%, and genotypes HPV16, HPV52, and HPV58 showed a relatively high prevalence.

The Tyr-X-X-Leu (YxxL) motif of the vaccinia virus F13L protein was examined for late (L) domain activity. The ability of an F13L deletion virus to form plaques was restored by PCR products containing single alanine substitutions within the motif and a YAAL construct but not by constructs lacking both the Y and L residues. Recombinant viruses possessing alanine substitutions in place of the tyrosine or the leucine residue in the YxxL motif demonstrated small, asymmetrical plaques. RNA interference-dependent depletion of Alix and TSG101 (host proteins involved in L domain-dependent protein trafficking) diminished extracellular enveloped virion production to various degrees, suggesting that the YxxL motif is a genuine L domain.