Venezuelan equine encephalitis virus (VEE) causes a biphasic disease in mice following subcutaneous inoculation in the footpad. In the initial phase, virus replicates primarily in the lymphoid tissues and induces a high titer viremia. Subsequently, the virus invades the central nervous system (CNS) from the circulation, and an encephalitis ensues. At the earliest times that VEE specific in situ hybridization signal was observed in the CNS, it was in areas of the brain involved in olfaction, leading to the hypothesis that virus may invade the brain from the circulation through the olfactory system. The results presented in this paper define the route of CNS invasion in experimental murine VEE disease initiated by subcutaneous inoculation. Virus circulating in the blood appears to seed specific areas of the peripheral nervous system during the viremic lymphoid phase of the illness. Virus replication within olfactory and dental tissues is followed by centripetal spread of virus along neural pathways. Virus enters the brain in a pattern reflecting the proximity of the peripheral invasion site to the CNS. Specifically, virus is first found in the brain within the structures of the olfactory system, followed by areas innervated by the trigeminal nerve. Virus later disseminates along fiber tracts and connected circuits within the brain, resulting in a disseminated meningoencephalitis. Surgical or chemical interruption of the olfactory system at the level of the olfactory neuroepithelium or the main olfactory bulb inhibited entry of VEE into the CNS through the olfactory nerve. However, the olfactory route is not absolutely required for CNS invasion, as virus invaded the CNS of olfactory ablated animals through the trigeminal nerve. These observations are consistent with a model of hematogenous seeding of the peripheral nervous system, followed by invasion of the CNS by direct neural spread.

Clotrimazole effectively inhibits cell proliferation and tumor growth, and prolongs survival of rats with intracranial gliomas. Clotrimazole may be considered a potential anticancer drug for treatment of intracranial gliomas.

Reporter gene expression in the olfactory epithelium of H-lacZ6 transgenic mice mimics the cell-selective expression pattern known for some odorant receptor genes. The transgene construct in these mice consists of the lacZ coding region, driven by the proximal olfactory marker protein (OMP) gene promoter, and shows expression in a zonally confined subpopulation of olfactory neurons. To address mechanisms underlying the odorant receptor-like expression pattern of the lacZ construct, we analyzed the transgene-flanking region and identified OR-Z6, the first cloned odorant receptor gene that maps to mouse chromosome 6. OR-Z6 bears the highest sequence similarity (85%) to a human odorant receptor gene at the syntenic location on human chromosome 7. We analyzed the expression pattern of OR-Z6 in olfactory tissues of H-lacZ6 mice and show that it bears strong similarities to that mapped for ␤-galactosidase. Expression of both genes in olfactory neurons is primarily restricted to the same medial subregion of the olfactory epithelium. Axons from both neuronal subpopulations project to the same ventromedial aspect of the anterior olfactory bulbs. Furthermore, colocalization analyses in H-lacZ6 mice demonstrate that OR-Z6-reactive glomeruli receive axonal input from lacZ-positive neurons as well. These results suggest that the expression of both genes is coordinated and that transgene expression in H-lacZ6 mice is regulated by locusdependent mechanisms.

Purpose: Vitamin E succinate (a-TOS) inhibits the growth of cancer cells without unacceptable side effects.Therefore, the mechanisms associated with the anticancer action of a-TOS, including ceramide-mediated apoptosis, were investigated using head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. Experimental Design: Five different human HNSCC cell lines (JHU-011, JHU-013, JHU-019, JHU-022, and JHU-029) were treated with a-TOS, and its effects on cell proliferation, cell cycle progression, ceramide-mediated apoptosis, and ceramide metabolism were evaluated. The anticancer effect of a-TOS was also examined on JHU-022 solid tumor xenograft growth in immunodeficient mice. Results: a-TOS inhibited the growth of all the HNSCC cell lines in vitro in a dose-and timedependent manner. Thus, JHU-013 and JHU-022 cell lines were more sensitive to a-TOS than the other cell lines. Cellular levels of ceramide, sphingomyelinase activity, caspase-3, and p53 were elevated with increasing time of exposure to a-TOS. The degradation of poly(ADP-ribose) polymerase protein in JHU-022 cells treated with a-TOS provided evidence for apoptosis. The amounts of nuclear factor nB, Bcl-2, and Bcl-X L proteins were reduced in the cells treated with a-TOS for 6 hours. The levels of caspase-9, murine double minute-2, and InB-a proteins were unchanged after a-TOS treatment. I.p. administration of a-TOS slowed tumor growth in immunodeficient mice. Conclusions: a-TOS showed promising anticancer effects to inhibit HNSCC growth and viability in vivo and in vitro. The induction of enzymes involved in ceramide metabolism by a-TOS suggests that ceramide-mediated apoptosis may expand therapeutic strategies in the treatment of carcinoma.Each year, f31,000 Americans are diagnosed with head and neck cancer and f7,400 die from the disease (1). Overall survival rates of head and neck cancers have only marginally improved over the last three decades (2). In addition, the incidence of oral cancer in African American men has been approximately twice higher than in Caucasian men, and the 5-year relative survival is lower for African Americans (1).Therefore, novel therapeutic and preventive approaches are warranted.Accumulating evidence suggested that an esterified derivative of RRR-a-tocopherol (a-TOH), RRR-a-tocopheryl succinate (a-TOS), is a vitamin E analogue, which inhibits tumor growth (3 -7). It induces apoptosis, inhibits tumor cell proliferation and differentiation, arrests DNA synthesis, and blocks cell cycle progression in various cancer cell lines and animal models of breast, colon, head and neck, prostate, and lung cancers (8 -18). In addition, a-TOS selectively kills tumor cells without toxic effects on normal cells and tissues (4,7,18). The parent compound of vitamin E, a-TOH, is a free radical -scavenging antioxidant, which protects polyunsaturated fats from peroxidation in human body but does not induce cancer cell apoptosis (19). In contrast to a-TOH, a-TOS is a redox-inactive molecule, which has a charged side group when i...

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