Justin C. Leavitt

Background and Aims: Incisional hernia prevention has become an important concept for surgeons operating on the abdominal wall. Several techniques have been proposed to help decrease incisional hernia formation with suture closure of the abdominal wall being one of the cornerstones. Technical details that have been reported to decrease incisional hernia rates include achieving a 4:1 Suture to Wound length ratio and the use of a small bites technique. Despite evidence to support many of these techniques there appears to be a gap in practice patterns amongst practicing surgeons. Introducing and promoting these principles in surgical residency may help to close this gap. This paper reviews our experience with surgical training for abdominal wall closures at our institution.Materials and Methods: Programs and projects related to abdominal wall closure were reviewed from our institution from 2010-Present. Type of project, intervention, and impact on education was evaluated and summarized.Results: Seven projects were identified relating to surgical training and abdominal wall closure. Three projects dealt with skills training using an abdominal wall simulation model and related to suturing techniques. Two projects were clinical studies focused on suture to wound length ratios and improving outcomes with this variable in a residency training program. Two projects dealt with models relating to abdominal wall closure and education.Conclusion: Implementation of educational programs in surgical residency programs can lead to improvements in technique and knowledge around abdominal wall closure and help in research endeavors.

ID 53227 Poster Board 492 Background and Objectives: Our efforts at Hamit-Darwin-Freesh, Inc are directed toward the discovery of therapeutic options that offer a credible approach to the prevention of Alzheimer9s disease (AD). For more than a decade there has evolved a strong consensus that AD is the sequelae of the action of so-called "toxic soluble ß-amyloid oligomers" on select neuronal populations in brain. Protofibrils (roughly equivalent to 150 monomers) are less soluble (and less toxic), and precede plaque formation. Others have shown that while ß-amyloid42 is present in a lesser amount than ß-amyloid40, the 42 amino acid peptide is most toxic to neurons. Also, several studies have shown that one or more forms of ß-amyloid trigger the formation of hyperphosphorylated tau. For these reasons, we chose to direct our efforts toward the discovery of molecules that prevent the aggregation of ss-amyloid42 monomers and oligomers. After years of exhaustive study, and drawing upon the very limited available art, our first molecule of interest (HDF2021-1) was admittedly derived largely from pharmacological intuition; and serendipity. HDF2021-1 and structural analogs in our small library are novel. That is, they do not exist in any chemical database, and there are no recorded syntheses. Here we report on HDF2021-1. Methods: Initial efficacy studies were done in two distinct E. coli clones, each having an IPTG-inducible plasmid that expressed ss-amyloid42. Subsequent studies were done with pure synthetic ss-amyloid42, as well as a ß-amyloid42 fluorophore. All studies utilized Western Blot, stain-free, fluorescent, and coomassie blue gel technique, as well as fluorescent spectroscopy. Methods in cell culture were also employed, utilizing the BE(2)-M17 neuron cell line. In gel methodology, individual bands and total amyloid were quantified. Cell-free studies often employed variable concentrations of protease, thermolysin and neprilysin, among others; and protease inhibitors. Results, Conclusion and Commentary: Early results in transformed E. coli showed that HDF2021-1 decreased the concentration of ß-amyloid42 (Western Blot), and curiously this effect was blocked by a protease inhibitor. A similar result was seen in BE(2)-M17 cell culture. Similar results were also observed in cell-free studies when thermolysin or neprilysin were added. Fluorescent spectroscopy showed amyloid self-quenching, while low concentrations of HDF2021–1 prevent this. In the absence of protease, HDF2021-1 modestly unquenches the signal. But with protease present, HDF2021-1 markedly potentiates this effect. Gel studies with protease added show that HDF2021-1 markedly reduces oligomer size. These effects show high selectivity for amyloid. We conclude that HDF2021-1 directly disaggregates ß-amyloid42 oligomers, but more notable is its effect to increase intrinsic protease action. Presently, we do not know if the effect is mediated by a direct action on amyloid oligomers, or an effect on protease. Efforts to clarify this question are ongoing. Also, FTIR and circular dichroism studies are underway to better understand molecular mechanisms. Other groups have studied other aggregation inhibitors, yet none have received FDA approval for AD treatment/prevention. Nonetheless, we believe that a very high therapeutic index drug having a favorable pharmacokinetic profile will emerge and be found to be very effective in the prevention of AD. Such a drug should be relatively inexpensive and widely available.

Bacteriophages are vastly abundant, diverse, and influential, but with few exceptions (e.g. the Proteobacteria genera Wolbachia and Hamiltonella), the role of phages in heritable bacteria-arthropod interactions, which are ubiquitous and diverse, remains largely unexplored. Despite prior studies documenting phage-like particles in the mollicute Spiroplasma associated with Drosophila flies, genomic sequences of such phage are lacking, and their effects on the Spiroplasma-Drosophila interaction have not been comprehensively characterized. We used a density step gradient to isolate phage-like particles from the male-killing bacterium Spiroplasma poulsonii (strains NSRO and MSRO-Br) harbored by Drosophila melanogaster. Isolated particles were subjected to DNA sequencing, assembly, and annotation. Several lines of evidence suggest that we recovered phage-like particles of similar features (shape, size, DNA content) to those previously reported in Drosophila-associated Spiroplasma strains. We recovered three ~ 19 kb phage-like contigs (two in NSRO and one in MSRO-Br) containing 21–24 open reading frames, a read-alignment pattern consistent with circular permutation, and terminal redundancy (at least in NSRO). Although our results do not allow us to distinguish whether these phage-like contigs represent infective phage-like particles capable of transmitting their DNA to new hosts, their encoding of several typical phage genes suggests that they are at least remnants of functional phage. We also recovered two smaller non-phage-like contigs encoding a known Spiroplasma toxin (Ribosome Inactivating Protein; RIP), and an insertion element, suggesting that they are packaged into particles. Substantial homology of our particle-derived contigs was found in the genome assemblies of members of the Spiroplasma poulsonii clade.

Bacteriophages are vastly abundant, diverse, and influential, but with few exceptions (e.g. the Proteobacteria genera Wolbachia and Hamiltonella ), the role of phages in heritable bacteria-arthropod interactions, which are ubiquitous and diverse, remains largely unexplored. Despite prior studies documenting phage-like particles in the mollicute Spiroplasma associated with Drosophila flies, genomic sequences of such phage are lacking, and their effects on the Spiroplasma - Drosophila interaction have not been comprehensively characterized. We used a density step gradient to isolate phage-like particles from the male-killing bacterium Spiroplasma poulsonii (strains NSRO and MSRO-Br) harbored by Drosophila melanogaster . Isolated particles were subjected to DNA sequencing, assembly, and annotation. Several lines of evidence suggest that we recovered phage-like particles of similar features (shape, size, DNA content) to those previously reported in Drosophila -associated Spiroplasma strains. We recovered three ∼19 kb phage-like contigs (two in NSRO and one in MSRO-Br) containing 21–24 open reading frames, a read-alignment pattern consistent with circular permutation, and terminal redundancy (at least in NSRO). Although our results do not allow us to distinguish whether these phage-like contigs represent infective phage-like particles capable of transmitting their DNA to new hosts, their encoding of several typical phage genes suggests that they are at least remnants of functional phage. We also recovered two smaller non-phage-like contigs encoding a known Spiroplasma toxin (Ribosome Inactivating Protein; RIP), and an insertion element, suggesting that they are packaged into particles. Substantial homology of our particle-derived contigs was found in the genome assemblies of members of the Spiroplasma poulsonii clade.

Tailed double-stranded DNA bacteriophages inject some proteins with their dsDNA during infection. Phage P22 injects about 12, 12, and 30 molecules of the proteins encoded by genes 7, 16 and 20, respectively. After their ejection from the virion, they assemble into a trans-periplasmic conduit through which the DNA passes to enter the cytoplasm. The location of these proteins in the virion before injection is not well understood, although we recently showed they reside near the portal protein barrel in DNA-filled heads. In this report we show that when these proteins are missing from the virion, a longer than normal DNA molecule is encapsidated by the P22 headful DNA packaging machinery. Thus, the ejection proteins occupy positions within the virion that can be occupied by packaged DNA when they are absent.

Serratia marcescensis a ubiquitous Gram-negative opportunistic pathogen. This announcement describes the isolation and genome annotation ofS. marcescensT5-like siphophage Slocum. Terminal repeats, 170 protein-coding genes, and 23 tRNAs were predicted in the 112,436-bp Slocum genome.