Out on the farm with DNA vaccines

DNA vaccination is a rapidly developing technology that offers new approaches for the prevention of disease. This technology may permit the production of new vaccines against diseases that have no current vaccine, as well as allowing the development of improved vaccines to replace existing products. We describe how DNA vaccination is being developed for use in commercial animal production, with an emphasis on viral diseases, and discuss the existing hurdles to its development and use.     

Alcohol availability and domestic violence

The purpose of this study was to examine the relationship among sociodemographic variables, alcohol outlet density, and rate of domestic violence in New Jersey. Data were obtained for the 223 largest municipalities in the state and were examined using factor analysis and bivariate and multivariate analyses. Three sociodemographic factors were extracted through factor analysis. These explained 58% of the variance among municipalities in rates of domestic violence. One factor--termed social disadvantage--explained the greatest amount of unique variance (42%). Alcohol outlet density added nothing to the sociodemographic model and did not interact with any of the three sociodemographic factors. The findings show that, in the state of New Jersey, higher levels of alcohol outlet density are not geographically associated with higher rates of domestic violence. These findings may be due to limitations in the data sets employed in the study, limitations of the macrolevel analysis employed, and/or the complex nature of the relationship between alcohol use and domestic violence.     

Identification and analysis of genes involved in anaerobic toluene metabolism by strain T1: putative role of a glycine free radical

The denitrifying strain T1 is able to grow with toluene serving as its sole carbon source. Two mutants which have defects in this toluene utilization pathway have been characterized. A clone has been isolated, and subclones which contain tutD and tutE, two genes in the T1 toluene metabolic pathway, have been generated. The tutD gene codes for an 864-amino-acid protein with a calculated molecular mass of 97,600 Da. The tutE gene codes for a 375-amino-acid protein with a calculated molecular mass of 41,300 Da. Two additional small open reading frames have been identified, but their role is not known. The TutE protein has homology to pyruvate formate-lyase activating enzymes. The TutD protein has homology to pyruvate formate-lyase enzymes, including a conserved cysteine residue at the active site and a conserved glycine residue that is activated to a free radical in this enzyme. Site-directed mutagenesis of these two conserved amino acids shows that they are also essential for the function of TutD.     

Dopamine depletion reorganizes projections from the nucleus accumbens and ventral pallidum that mediate opioid-induced motor activity

Motor activity elicited pharmacologically from the nucleus accumbens by the mu-opioid receptor agonist D-Ala-Tyr-Gly-NMePhe-Gly-OH (DAMGO) is augmented in rats sustaining dopamine depletions. GABAergic projections from the nucleus accumbens to ventral pallidum and ventral tegmental area (VTA) are involved because stimulation of GABAB receptors in the VTA (by baclofen) or GABAA receptors in the ventral pallidum (by muscimol) inhibit the motor response induced by the microinjection of DAMGO into the nucleus accumbens. The present study was done to determine which of these projections is mediating the augmented DAMGO-induced motor activity that follows 6-hydroxydopamine lesions of the nucleus accumbens. The inhibition of DAMGO-induced activation by pallidal injections of muscimol was markedly attenuated in lesioned animals, whereas the inhibition by VTA injections with baclofen was greatly enhanced. A similar switch in emphasis from pallidal to mesencephalic efferents was not observed for dopamine-induced motor activity, because muscimol microinjections inhibited the response elicited by dopamine microinjection into the nucleus accumbens in all subjects. The stimulation of mu-opioid receptors in the ventral pallidum also elicits motor activation, and this is blocked by baclofen microinjection into the VTA. However, after dopamine depletion in the nucleus accumbens, baclofen in the VTA was ineffective in blocking the motor response by DAMGO in the ventral pallidum. These data reveal that dopamine depletion in the nucleus accumbens produces a lesion-induced plasticity that alters the effect of mu-opioid receptor stimulation on efferent projections from the nucleus accumbens and ventral pallidum.     

A methylated Neurospora 5S rRNA pseudogene contains a transposable element inactivated by repeat-induced point mutation

In an analysis of 22 of the roughly 100 dispersed 5S rRNA genes in Neurospora crassa, a methylated 5S rRNA pseudogene, Psi63, was identified. We characterized the Psi63 region to better understand the control and function of DNA methylation. The 120-bp 5S rRNA-like region of Psi63 is interrupted by a 1.9-kb insertion that has characteristics of sequences that have been modified by repeat-induced point mutation (RIP). We found sequences related to this insertion in wild-type strains of N. crassa and other Neurospora species. Most showed evidence of RIP; but one, isolated from the N. crassa host of Psi63, showed no evidence of RIP. A deletion from near the center of this sequence apparently rendered it incapable of participating in RIP with the related full-length copies. The Psi63 insertion and the related sequences have features of transposons and are related to the Fot1 class of fungal transposable elements. Apparently Psi63 was generated by insertion of a previously unrecognized Neurospora transposable element into a 5S rRNA gene, followed by RIP. We name the resulting inactivated Neurospora transposon PuntRIP1 and the related sequence showing no evidence of RIP, but harboring a deletion that presumably rendered it defective for transposition, dPunt.     

The response of periodontal ligament cells to fibronectin

Fibronectin (fn) is an extracellular matrix (ECM) molecule important in cell adhesion and migration and in wound healing. It is also likely important in periodontal ligament (PDL) cell-ECM interactions, and thus in regenerating periodontal tissues. In this study we characterized PDL cells and their interactions with FN, testing different PDL cell isolates taken from healthy and diseased conditions. PDL cells were characterized by their morphology, integrin profile, motility, and bone nodule formation. Cells were then assayed for adhesion, proliferation, and chemotaxis in response to FN or FN fragments. Cell isolates were morphologically heterogeneous and fibroblastic, had a normal-appearing actin cytoskeleton and a wide range of migration potentials, and formed bone-like nodules in vitro. They expressed alpha5, beta1, alpha v, and alpha4 integrin subunits, known receptors for FN, and in fact they bound FN preferentially at 5 and 10 microg/ml. Intact FN induced greater PDL cell proliferation and chemotaxis than did FN fragments (120-kDa cell-binding, 60-kDa heparin-binding, and 45-kDa collagen-binding). PDL cells harvested from diseased and healthy conditions were no different on the basis of these assays. These data demonstrate that PDL cells are a mixed population of fibroblastic cells, capable of forming a mineralized matrix. They also suggest that maximal proliferation and chemotaxis require specific FN domains that are present on the intact molecule but not its fragments.