Design and synthesis of orally-active and selective azaindane 5HT2c agonist for the treatment of obesity

Based on our original pyrazine hit, CP-0809101, novel conformationally-restricted 5HT2c receptor agonists with 2-piperazin-azaindane scaffold were designed. Synthesis and structure–activity relationship (SAR) studies are described with emphasis on optimization of the selectivity against 5HT2a and 5HT2b receptors with excellent 2c potency. Orally-active and selective compounds were identified with dose–responsive in vivo efficacy in our pre-clinical food intake model.     

Expanded Multilocus Sequence Typing and Comparative Genomic Hybridization of Campylobacter coli Isolates from Multiple Hosts

The purpose of this work was to evaluate the evolutionary history of Campylobacter coli isolates derived from multiple host sources and to use microarray comparative genomic hybridization to assess whether there are particular genes comprising the dispensable portion of the genome that are more commonly associated with certain host species. Genotyping and ClonalFrame analyses of an expanded 16-gene multilocus sequence typing (MLST) data set involving 85 isolates from 4 different hosts species tentatively supported the development of C. coli host-preferred groups and suggested that recombination has played various roles in their diversification; however, geography could not be excluded as a contributing factor underlying the history of some of the groups. Population genetic analyses of the C. coli pubMLST database by use of STRUCTURE suggested that isolates from swine form a relatively homogeneous genetic group, that chicken and human isolates show considerable genetic overlap, that isolates from ducks and wild birds have similarity with environmental water samples and that turkey isolates have a connection with human infection similar to that observed for chickens. Analysis of molecular variance (AMOVA) was performed on these same data and suggested that host species was a significant factor in explaining genetic variation and that macrogeography (North America, Europe, and the United Kingdom) was not. The microarray comparative genomic hybridization data suggested that there were combinations of genes more commonly associated with isolates derived from particular hosts and, combined with the results on evolutionary history, suggest that this is due to a combination of common ancestry in some cases and lateral gene transfer in others.Campylobacter species are a leading bacterial cause of gastroenteritis within the United States and throughout much of the rest of the developed world. According to the CDC, there are an estimated 2 million to 4 million cases of Campylobacter illness each year in the United States (37). Campylobacter jejuni is generally recognized as the predominant cause of campylobacteriosis, responsible for approximately 90% of reported cases, while the majority of the remainder are caused by the closely related sister species Campylobacter coli (27). Not surprisingly, therefore, the majority of research on Campylobacter has centered on C. jejuni, and C. coli is a less studied organism.A multilocus sequence typing (MLST) scheme of C. jejuni was first developed by Dingle et al. (13) on the basis of the genome sequence of C. jejuni NCTC 11168. There have also been a number of studies using the genome sequence data to develop microarrays for gene presence/absence determination across strains of C. jejuni and to identify the core genome components for the species (6, 15, 32, 33, 42, 43, 53, 57). Although C. coli is responsible for fewer food-borne illnesses than C. jejuni, the impact of C. coli is still substantial, and there is also evidence that C. coli may carry higher levels of resistance to some antibiotics (1). C. coli and C. jejuni also tend to differ in their relative prevalences in animal host species and various environmental sources (4, 48, 58), and there is some evidence that both taxa may include groups of host-specific putative ecotype strains (7, 36, 38, 39, 52, 56). At present, there is only a single draft genome sequence available for C. coli, and there are no microarray comparative genomic hybridization data for C. coli strains. Thus, there is no information on intraspecies variability in gene presence/absence in C. coli and how such variability might correlate with host species.The purpose of this work was to develop and apply an expanded 16-locus MLST genotyping scheme to evaluate the evolutionary history of Campylobacter coli isolates derived from multiple host sources and to use microarray comparative genomic hybridization to assess whether there are particular genes comprising the dispensable portion of the genome that are more commonly associated with isolates derived from different host species.     

Canalization breakdown and evolution in a source-sink system

Understanding the process of adaptation to novel environments may help to elucidate several ecological phenomena, from the stability of species range margins to host-pathogen specificity and persistence in degraded habitats. We study evolution in one type of novel environment: a sink habitat where populations cannot persist without recurrent immigration from a source population. Previous studies on source-sink evolution have focused on how extrinsic environmental factors influence adaptation to a sink, but few studies have examined how intrinsic genetic factors influence adaptation. We use an individual-based model to explore how genetic canalization that evolves in gene regulation networks influences the adaptation of a population to a sink. We find that as canalization in the regulation network increases, the probability of adaptation to the novel habitat decreases. When adaptation to the habitat does occur, it is usually preceded by a breakdown of canalization. As evolution continues in the novel habitat, canalization reemerges, but a legacy of the breakdown may remain, even after several generations. We also find that environmental noise tends to increase the probability of adaptation to the novel habitat. Our results suggest that the details of genetic architecture can significantly influence the likelihood of niche evolution in novel environments.     

Discovery of potent and orally bioavailable heterocycle-based beta3-adrenergic receptor agonists, potential therapeutics for the treatment of obesity

A novel series of heterocycle-based analogs were prepared and evaluated for their in vitro and in vivo biological activity as human beta(3)-adrenergic receptor (AR) agonists. Several analogs demonstrated potent agonist activity at the beta(3)-AR, functional selectivity against beta(1)- and beta(2)-ARs, and favorable pharmacokinetic profiles in vivo. Compound 17 increased oxygen consumption in rats, a measure of energy expenditure, with an ED(20%) of 2mg/kg.     

Incorporation of CpG oligonucleotide ligand into protein-loaded particle vaccines promotes antigen-specific CD8 T-cell immunity

The development of multicomponent biotherapeutic carriers is an important challenge in the field of drug delivery, particularly in the area of protein-based vaccines. While the delivery of protein antigens to antigen presenting cells (APCs) is crucial for this type of vaccination, the incorporation of additional adjuvants may be just as important in order to generate more potent immune responses. This article presents the synthesis and biological evaluation of carrier particles that both deliver a protein payload to APCs and display receptor ligands for the enhancement of APC immunostimulation. Particles displaying CpG oligonucleotide ligands for Toll-like receptor 9 were synthesized. The addition of CpG DNA to the particles led to a 45-fold increase in the secretion of interleukin-12, a cytokine that aids in T-cell activation, and a significant increase in the expression of costimulatory molecules by APCs. Moreover, vaccination with particles containing both ovalbumin (OVA) and CpG DNA induced a superior OVA-specific CD8 T-cell response in vivo, as measured by increased OVA-specific CD8 T-cell proliferation, secretion of the proinflammatory cytokine IFN-gamma, and the induction of OVA-specific cytotoxicity.     

Lipophosphoramidates as lipidic part of lipospermines for gene delivery

The DNA compacting properties of polyamines (especially spermine) are well-known, hence the use of spermine as the cationic part in several synthetic DNA carriers. Here, we describe the synthesis of modified spermines, with a "lipophosphoramidate" as the lipidic part, and their use for efficient in vitro transfection. Physicochemical measurements (particle size, zeta potentials, pKa determination) and gel retardation assays were also performed. Theoretical membrane-disrupting ability was established by FRET. Taken together, our results indicate that lipophosphoramidates constitute an interesting alternative to "classical" lipidic parts of cationic lipids used as DNA carriers.     

LTP inhibits LTD in the hippocampus via regulation of GSK3beta

Glycogen synthase kinase-3 (GSK3) has been implicated in major neurological disorders, but its role in normal neuronal function is largely unknown. Here we show that GSK3beta mediates an interaction between two major forms of synaptic plasticity in the brain, N-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) and NMDA receptor-dependent long-term depression (LTD). In rat hippocampal slices, GSK3beta inhibitors block the induction of LTD. Furthermore, the activity of GSK3beta is enhanced during LTD via activation of PP1. Conversely, following the induction of LTP, there is inhibition of GSK3beta activity. This regulation of GSK3beta during LTP involves activation of NMDA receptors and the PI3K-Akt pathway and disrupts the ability of synapses to undergo LTD for up to 1 hr. We conclude that the regulation of GSK3beta activity provides a powerful mechanism to preserve information encoded during LTP from erasure by subsequent LTD, perhaps thereby permitting the initial consolidation of learnt information.     

Aspergillus tubingensis Endocarditis: A Case Report and Review of the Literature

Mycopathologia - Aspergillus endocarditis is a rare infection that may affect immunocompetent patients following heart valve replacement or heart surgery. We report the case of a 39 year...