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Use of a combination of an effective gE gene-deleted pseudorabies virus (PRV) vaccine with a companion diagnostic kit for PRV glycoprotein gE has proven successful in several pseudorabies-eradication programs. To produce a large quantity of functional gE protein for development of a PRV-gE diagnostic kit, an Escherichia coli expression system containing the distal region of the PRV-gE gene of a PRV strain CF was constructed. The expressed protein contained 134 amino acids of gE protein (amino acids 77-210) fused to a 19-amino acids tag containing 6 histidine residues. After induction, a truncated PRV-gE polypeptide of 18-kd was expressed to about 20% of the total E coli proteins. Results of immunoblot analysis indicated that this E coli-produced PRV-gE protein reacted specifically with serum from PRV-hyperimmunized pigs and from field PRV-infected pigs, but not with serum samples from specific-pathogen-free pigs or pigs inoculated with gE-deleted PRV vaccine. These data indicate that, although the recombinant gE protein is produced in E coli, it still retains the antigenicity of the viral gE glycoprotein. Comparison between the recombinant gE protein, using immunoblot analysis with a commercial gE ELISA containing natural PRV-gE protein, revealed comparable test performance. This finding indicated that recombinant gE protein produced by E coli can be used for development of a companion serologic assay for a PRV-gE gene-deleted vaccine.

7197 Background: When evaluating non small cell lung cancer (NSCLC) pts for participation in clinical protocols, two of the major determinants are staging (IIIB vs IV) and performance status, PS. Staging does not consider extent of disease or sites of metastases, and pts with central nervous system (CNS) metastases are often excluded due to presumed poor survival. Methods: To test the hypothesis that number of metastic sites affects prognosis, we analyzed 1284 cases of metastatic NSCLC presenting as new patients to MD Anderson Cancer Center from 1998 - 2002. 1060 pts had 1,2, or 3 sites of mets. Survival was analyzed utilizing tumor registry and clinic records according to presence or absence of CNS mets and by 1, 2, 3, or any number of organ sites by log-rank test. Results: 1138/1284 (88.6%) have expired. 432 had CNS mets and 706 had none at registration. For up to 2 organ sites of metastases, the presence of brain metastases gave a slightly worse survival (Table). No difference in survival was seen betw...

A modified procedure for extraction and purification of hydrolyzed archaebacterial lipids is described. Lipids were extracted from Sulfolobus acidocaldarius using a Soxhlet extraction procedure followed by trichloroacetic acid solvent-extraction of the residue. The yield of total extractable material by this protocol was 14% which, after a two-phase wash, yielded 10% lipid. Modifications to the published steps for purifying the subsequently hydrolyzed lipids were developed to purify glycerol dialkyl nonitol tetraether (GDNT). The nearly colorless final macrocyclic product was characterized by TLC, IR, NMR, and mass spectrometry.

Damping of the vibrations of polymer chains due to friction with solvent, including hydrodynamic interaction between chain elements, is considered. The linear chain model is treated in detail. It is concluded that the damping constant is independent of the degree of polymerization. This conclusion is based on use of the high frequency hydrodynamic interaction. Only backbone vibrations of the chain are treated; localized group vibrations are not within the purview of the model.

Fusion between two lipid membranes is superficially easy to understand: Two lipid bilayers come into contact and meld into one seamless membrane. But even at this basic level, one must distinguish whether fusion simply means the merging of the two membranes or whether the internal contents (of the liposomes or vesicles) must also mix. Certainly, for the case of vesicles, the requirement that “true” fusion involves the mixing of the internal volumes as well as lipid mixing is a reasonable and practical way of defining fusion. There are other situations, however, where the above definition is inadequate. For instance, in modeling exocytosis, where the internal contents of a liposome is excreted outward, there is no mixing per se of two internal volumes. In this case, the essence of membrane fusion has to be defined slightly differently. Leaving aside such interesting considerations concerning the definition of fusion, there is also much unknown about the process of fusion. Certainly there are many pathways for initiating vesicle membrane fusion; a partial listing would include induction by cations (Papahadjopoulos et al., 1977), by pH (Ellens et al., 1984), by proteins (Morero et al., 1985), by temperature (Verkleij, 1980), by electric field (Zimmermann, 1982; Sowers, 1984), or even spontaneous fusion between vesicles (Suurkuusk et al., 1976; Schullery et al., 1980; Chang et al., 1982).

Assays based on lysis of lipid vesicles have shown high sensitivity. However, little as yet is known about the quantitative relationships among the various assay parameters, due in part to the lack of a predictive theoretical model. This paper presents the derivation of the equations that describe a simple model assay system in terms of the total fraction of vesicles with bound antibodies and the distribution of vesicles with one, two, or more antibodies bound. The equations show how the binding of antibodies to vesicles is affected by such variables as: vesicle concentration, antigen density on vesicle surfaces, antibody concentration, and antibody affinity. With the distribution functions, experiments can be designed to determine the minimum number of antibodies needed to lyse a vesicle. In addition, it is shown how estimations of the ultimate sensitivity of lipid vesicle lytic assays can be made. The model can be used to optimize vesicle lysis assay systems.