Microbicidal approaches to interdict virus infections in human epithelial cell cultures, organ tissue cultures and human epithelial xenografts

Sexually transmitted infections (STIs) are causing a hidden epidemic. Everyday infected individuals and their families quietly suffer physically, psychologically and financially. Worldwide, STIs are a major economic burden with direct medical costs for treating these diseases in United States alone is $15.3 billion per year. As with many diseases and infections, prevention is the key and with our current technology the best hope for prevention is microbicides. The work set forth in this thesis examined three vastly different microbicides each with very different modes for preventing the initial stages of HIV-1 infection. The prototypic SDS Hydrogel is a broad-spectrum microbicide. We show that our prototypic SDS Hydrogel has potent antiviral activity against enveloped (HIV-1 and HSV-2) and non-enveloped (HPV-11) sexually transmitted viruses. The second microbicide is comprised of a liposomal delivered short interfering RNA (siRNA) pool targeting human chemokine receptor 5 (CCR5). The down-regulation of CCR5 along with other molecules (gp340, syndecans, a4ß7 integrin), which allow HIV-1 to remain infectious, may potentially inhibit binding of R5 forms of HIV-1 from binding to the co-receptor, therefore, preventing the subsequent infection. Lastly, the recombinant L. plantarum secreting cyanovirin is a pro-biotic microbicide that decreased HIV-1 infectivity in vitro and we were able to recolonize human vaginal epithelia ex vivo and in vivo.Ph.D., Biology -- Drexel University, 200

A precursor to the relational evaluation procedure: Analyzing stimulus equivalence II

A series of experiments examined the precursor to the relational evaluation procedure (pREP). The pREP is capable of facilitating derived relational responding, but it is less effective than matching-to-sample (MTS) in producing equivalence class formation. Part 1 of the present study tested possible reasons for the inferiority of the. pREP relative to MTS. The first two experiments compared the performances of subjects on two modified versions of the pREP with their performances on a simultaneous MTS procedure. The modifications did not improve performances on the pREP. Experiment 3 compared the pREP with a delayed MTS procedure but again MTS was more effective than the pREP in producing equivalence. Part 2 of the study determined whether pREP equivalence responding could be facilitated by preexposing subjects to a history of MTS training and testing. In Experiment 4, subjects were trained and tested on a MTS procedure until they reliably produced both symmetry and equivalence, and were then exposed to pREP training and testing using the same stimuli, and relations among stimuli, as employed for the MTS procedure. Following this, subjects were exposed to pREP training and testing using novel stimuli. All subjects reliably produced both symmetry and equivalence responding on the pREP with both familiar arid novel stimuli. Experiment 5 determined whether using the same stimulus sets across the two procedures was necessary. Results showed that if symmetry and equivalence were shown on a MTS procedure followed immediately by pREP training and testing using novel stimuli, only 2 out of 4 subjects successfully demonstrated both symmetry and equivalence using the latter procedure

Relational frame theory and stimulus equivalence: Conceptual and procedural issues

The article begins with a brief outline of the phenomenon of stimulus equivalence and its relationship to human verbal behavior. Relational Frame Theory is then outlined as a behavior-analytic account of both stimulus equivalence and human language. The experimental procedures that have typically been used to examine stimulus equivalence are then considered, before focusing on a series of studies that have developed two alternative procedures for analyzing equivalence class formation: the respondent-type training procedure and the precursor to the relational evaluation procedure. Relational Frame Theory is used to interpret the results that have arisen from these two methodologies. The article concludes that the empirical and theoretical analyses of stimulus equivalence and derived relations, more generally, will be enhanced considerably through the development of a wide range of experimental preparations

Assessing stimulus equivalence with a precursor to the relational evaluation procedure

Previous research has demonstrated that, after being trained on multiple match-to-sample (MTS) tasks (A-B, B-C), most human adults respond in accordance with symmetry (B-A, C-B) and equivalence (C-A) when measured with MTS tests and with a precursor to the Relational Evaluation Procedure (pREP). The latter procedure involves conditional go/no-go discrimination tasks, requiring subjects to press a bar during a 5s interval after the successive presentation of two same-class stimuli, and not to press after the presentation of two different-class stimuli (e.g. Ci -->Ai -->press, Ci -->Aj -->no press). The present study was an effort to replicate these findings. The study consisted of five experiments. Very few subjects evidenced pREP symmetry and equivalence unless they had (a) already demonstrated symmetry and equivalence in a MTS test before, or (b) received pREP pretraining with unrelated stimulus pairs and symmetry was tested before equivalence. Failures to show symmetry were always associated with pressing at or close to 50% of these trials. Failures to show equivalence were associated with pressing or not pressing on (almost) all trials. Current findings are similar to those obtained in equivalence studies involving MTS probes permitting the subjects not to respond to the designated comparisons

Global Pharmacovigilance for Antiretroviral Drugs: Overcoming Contrasting Priorities

Jur Strobos and colleagues describe the deliberations of a recent multi-stakeholder meeting discussing the creation of a sustainable global pharmacovigilance system for antiretroviral drugs that would be applicable in resource limited settings

Gata3 Acts Downstream of β-Catenin Signaling to Prevent Ectopic Metanephric Kidney Induction

Metanephric kidney induction critically depends on mesenchymal–epithelial interactions in the caudal region of the nephric (or Wolffian) duct. Central to this process, GDNF secreted from the metanephric mesenchyme induces ureter budding by activating the Ret receptor expressed in the nephric duct epithelium. A failure to regulate this pathway is believed to be responsible for a large proportion of the developmental anomalies affecting the urogenital system. Here, we show that the nephric duct-specific inactivation of the transcription factor gene Gata3 leads to massive ectopic ureter budding. This results in a spectrum of urogenital malformations including kidney adysplasia, duplex systems, and hydroureter, as well as vas deferens hyperplasia and uterine agenesis. The variability of developmental defects is reminiscent of the congenital anomalies of the kidney and urinary tract (CAKUT) observed in human. We show that Gata3 inactivation causes premature nephric duct cell differentiation and loss of Ret receptor gene expression. These changes ultimately affect nephric duct epithelium homeostasis, leading to ectopic budding of interspersed cells still expressing the Ret receptor. Importantly, the formation of these ectopic buds requires both GDNF/Ret and Fgf signaling activities. We further identify Gata3 as a central mediator of β-catenin function in the nephric duct and demonstrate that the β-catenin/Gata3 pathway prevents premature cell differentiation independently of its role in regulating Ret expression. Together, these results establish a genetic cascade in which Gata3 acts downstream of β-catenin, but upstream of Ret, to prevent ectopic ureter budding and premature cell differentiation in the nephric duct

Genetic architecture of subcortical brain structures in 38,851 individuals

Subcortical brain structures are integral to motion, consciousness, emotions and learning. We identified common genetic variation related to the volumes of the nucleus accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen and thalamus, using genome-wide association analyses in almost 40,000 individuals from CHARGE, ENIGMA and UK Biobank. We show that variability in subcortical volumes is heritable, and identify 48 significantly associated loci (40 novel at the time of analysis). Annotation of these loci by utilizing gene expression, methylation and neuropathological data identified 199 genes putatively implicated in neurodevelopment, synaptic signaling, axonal transport, apoptosis, inflammation/infection and susceptibility to neurological disorders. This set of genes is significantly enriched for Drosophila orthologs associated with neurodevelopmental phenotypes, suggesting evolutionarily conserved mechanisms. Our findings uncover novel biology and potential drug targets underlying brain development and disease

Genetic architecture of subcortical brain structures in 38,851 individuals

Subcortical brain structures are integral to motion, consciousness, emotions and learning. We identified common genetic variation related to the volumes of the nucleus accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen and thalamus, using genome-wide association analyses in almost 40,000 individuals from CHARGE, ENIGMA and UK Biobank. We show that variability in subcortical volumes is heritable, and identify 48 significantly associated loci (40 novel at the time of analysis). Annotation of these loci by utilizing gene expression, methylation and neuropathological data identified 199 genes putatively implicated in neurodevelopment, synaptic signaling, axonal transport, apoptosis, inflammation/infection and susceptibility to neurological disorders. This set of genes is significantly enriched for Drosophila orthologs associated with neurodevelopmental phenotypes, suggesting evolutionarily conserved mechanisms. Our findings uncover novel biology and potential drug targets underlying brain development and disease

Zika virus protection by a single low dose nucleoside modified mRNA vaccination

Zika virus (ZIKV) has recently emerged as an explosive pandemic associated with severe neuropathology in newborns and adults1. There are no ZIKV-specific treatments or preventatives; thus, development of a safe and effective vaccine is a high priority. Messenger RNA (mRNA) has emerged as a versatile and highly effective platform to deliver vaccine antigens and therapeutic proteins2,3. Here, we demonstrate that a single low-dose intradermal immunization with lipid nanoparticle-encapsulated nucleoside-modified mRNA (mRNA-LNP) encoding the pre-membrane and envelope (prM-E) glycoproteins of a 2013 ZIKV outbreak strain elicited potent and durable neutralizing antibody responses in mice and non-human primates. Immunization with 30 μg of nucleoside-modified ZIKV mRNA-LNPs protected mice from ZIKV challenges at 2 weeks or 5 months post-vaccination, and a single dose of 50 μg was sufficient to protect non-human primates from a challenge at 5 weeks post-vaccination. These data demonstrate that nucleoside-modified mRNA-LNPs elicit rapid and durable protective immunity and thus represent a new and promising vaccine candidate for the global fight against ZIKV