Browsing by Author "Zhang, X."

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    Helminth infection reactivates latent γ-herpesvirus via cytokine competition at a viral promoter
    (American Association for the Advancement of Science, 2014-08) Reese, T.A.; Wakeman, B.S.; Choi, H.S.; Hufford, M.M.; Huang, S.C.; Zhang, X.; Buck, M.D.; Jezewski, A.; Kambal, A.; Liu, C.Y.; Goel, G.; Murray, P.J.; Xavier, R.J.; Kaplan, M.H.; Renne, R.; Speck, S.H.; Artyomov, M.N.; Pearce, E.J.; Virgin, H.W.; Pediatrics, School of Medicine
    Mammals are coinfected by multiple pathogens that interact through unknown mechanisms. We found that helminth infection, characterized by the induction of the cytokine interleukin-4 (IL-4) and the activation of the transcription factor Stat6, reactivated murine γ-herpesvirus infection in vivo. IL-4 promoted viral replication and blocked the antiviral effects of interferon-γ (IFNγ) by inducing Stat6 binding to the promoter for an important viral transcriptional transactivator. IL-4 also reactivated human Kaposi's sarcoma-associated herpesvirus from latency in cultured cells. Exogenous IL-4 plus blockade of IFNγ reactivated latent murine γ-herpesvirus infection in vivo, suggesting a "two-signal" model for viral reactivation. Thus, chronic herpesvirus infection, a component of the mammalian virome, is regulated by the counterpoised actions of multiple cytokines on viral promoters that have evolved to sense host immune status.
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    Nonvolatile voltage controlled molecular spin state switching
    (AIP, 2019) Hao, G.; Mosey, A.; Jiang, X.; Yost, A. J.; Sapkota, K. R.; Wang, G. T.; Zhang, X.; Zhang, J.; N’Diaye, A. T.; Cheng, R.; Xu, X.; Dowben, P. A.; Physics, School of Science
    Voltage-controlled room temperature isothermal reversible spin crossover switching of [Fe{H2B(pz)2}2(bipy)] thin films is demonstrated. This isothermal switching is evident in thin film bilayer structures where the molecular spin crossover film is adjacent to a molecular ferroelectric. The adjacent molecular ferroelectric, either polyvinylidene fluoride hexafluoropropylene or croconic acid (C5H2O5), appears to lock the spin crossover [Fe{H2B(pz)2}2(bipy)] molecular complex largely in the low or high spin state depending on the direction of ferroelectric polarization. In both a planar two terminal diode structure and a transistor structure, the voltage controlled isothermal reversible spin crossover switching of [Fe{H2B(pz)2}2(bipy)] is accompanied by a resistance change and is seen to be nonvolatile, i.e., retained in the absence of an applied electric field. The result appears general, as the voltage controlled nonvolatile switching can be made to work with two different molecular ferroelectrics: croconic acid and polyvinylidene fluoride hexafluoropropylene.