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Proliferating trichilemmal tumor (PTT) is a rare adnexal neoplasm that arises from the outer sheath of the hair follicle. It is believed that PTTs originate in trichilemmal cysts. These tumors have the potential for malignant transformation; when this occurs, the tumor is known as a malignant PTT (MPTT). Recurrence after simple local excision is common, and it can cause considerable morbidity. We report a case of MPTT that was initially diagnosed as a benign PTT. The primary tumor had arisen from the skin over the glabella. It was excised, but it recurred 3 years postoperatively. The recurrent tumor involved the eyelid, nasal cavity, and frontal and ethmoid sinuses, and it extended into the orbit. The recurrent tumor was excised via combined endoscopic and open surgery. As far as we know, this is the first documented case of an MPTT that involved the sinuses. [ABSTRACT FROM AUTHOR]

Replicon particles based on Venezuelan equine encephalitis virus (VEE) contain a self-replicating RNA encoding the VEE replicase proteins and expressing a gene of interest in place of the viral structural protein genes. Structural proteins for packaging of replicon RNA into VEE replicon particles (VRPs) are expressed from separate helper RNAs. Aspects of the biology of VEE that are exploited in VRP vaccines include 1) expression of very high levels of immunogen, 2) expression of immunizing proteins in cells in the draining lymph node, and 3) the ability to induce mucosal immunity from a parental inoculation. Results of experiments with VRPs expressing green fluorescent protein or influenza virus hemagglutinin (HA) demonstrated that specific mutations in the VRP envelope glycoproteins affect both targeting in the draining lymph node and efficiency of the immune response in mice. VRPs expressing either the matrix-capsid portion of Gag, the full-length envelope gp160, or the secreted gp140 of cloned SIVsm H-4i were mixed in a cocktail and used to immunize macaques at 0, 1, and 4 months. Neutralizing antibodies against SIVsm H-4 were induced in 6 of 6 vaccinates and CTL in 4 of 6. An intrarectal challenge with the highly pathogenic SIVsm E660 was given at 5 months. A vaccine effect was seen in reduced peak virus loads, reduced virus loads both at set point and at 41 weeks postchallenge, and preserved or increased CD4 counts compared to controls. A candidate VRP HIV vaccine expressing Clade C Gag contains a sequence that is very close to the South African Clade C consensus and was selected from a recent seroconverter in the Durban cohort to represent currently circulating genotypes in South Africa. A GMP lot of this vaccine has been manufactured and tested for a phase I trial in the first months of 2002.