Evolving Networks of Expertise

<p>Presentation given by Dr William Gunn during the Research Trends Virtual Seminar</p> <p>The Individual and Scholarly Networks: Part 1: Building Networks:</p> <p> </p> <p>Dr William Gunn of Mendeley talked on building networks through information linking, rather than connecting people through known relationships.</p

The Individual and Scholarly Networks: Building Networks - Discussion

<p>The Individual and Scholarly Networks was a two-part seminar organized by Research Trends and Elsevier Labs on January 22, 2013. Webcast live from Oxford, Amsterdam and New York, the presentations were recorded and are available here, along with links to slides and additional questions and answers. The seminar was led by Michael Taylor, Research Specialist at Elsevier Labs with additional contributions from Dr Henk Moed and Dr Gali Halevi of Research Trends</p> <p>Researchers are increasingly using social network type platforms to form relationships and ad-hoc research reading groups.</p> <p>Part 1 - Building Networks focused on the ways in which these relationships are formed and maintained, and how they are changing the nature of scholarly relationships.</p> <p> </p> <p> </p

Replication Attempt: “Effect of BMAP-28 Antimicrobial Peptides on Leishmania Major Promastigote and Amastigote Growth: Role of Leishmanolysin in Parasite Survival”

<div><p>This study describes an attempt to replicate experiments from the paper “Effect of BMAP-28 Antimicrobial Peptides on <i>Leishmania major</i> Promastigote and Amastigote Growth: Role of Leishmanolysin in Parasite Survival,” which was submitted to the Reproducibility Initiative for independent validation. The cathelicidin bovine myeloid antimicrobial peptide 28 (BMAP-28) and its isomers were previously shown to have potent antiparasitic activity against <i>Leishmania major.</i> We tested the effectiveness of L-BMAP-28 and two of its isomers, the D-amino acid form (D-BMAP-28) and the retro-inverso form (RI-BMAP-28), in both unamidated and amidated forms, as anti-leishmanial agents against <i>Leishmania major</i> promastigotes <i>in vitro</i>. We observed that L-BMAP-28, as well as its D and RI isomers, demonstrate anti-leishmanial activity against <i>L. major</i> promastigotes <i>in vitro</i>. The inhibitory effect was lower than what was seen in the original study. At 2 µM of amidated peptides, the viability was 94%, 36%, and 66% with L-, D- and RI-peptides, versus 57%, 6%, and 18% in the original study.</p></div

HPLC profile and mass spectrum of synthesized amidated BMAP-28 peptides.

<p>The peptides (Sequence: GGLRSLGRKILRAWKKYGPIIVPIIRI-NH₂; M.W: 3131.92; Formula: C147H252N44O31) were isolated and purified by high-performance liquid chromatography (HPLC) to greater than 95% purity. The purity and molecular weight of the respective peptides were confirmed by matrix-assisted laser desorption ionization (MALDI)-time of flight mass spectrometry. Left panels: HPLC profile, right panels: mass spectrum. A) L-BMAP-28-NH₂, purity 95.64%; B) D-BMAP-28-NH₂, purity 95.35%; C) RI-BMAP-28-NH₂, purity 95.85%; D) Scrambled-BMAP-28-NH₂, purity 95.19%.</p

Promastigote viability assay of <i>Leishmania major</i> when treated with amidated BMAP-28 variants.

<p><i>L. major</i> MHOM/SN/74/SD strain was treated with L-, RI- and D-BMAP-28 peptides for 4 hours. Viability was expressed as a percentage of untreated control cells. Three complete biological replicates were performed and the standard errors are shown.</p

HPLC profile and mass spectrum of synthesized unmodified BMAP-28 peptides.

<p>The peptides (Sequence: GGLRSLGRKILRAWKKYGPIIVPIIRIG; M.W: 3131.92; Formula: C147H252N44O31) were isolated and purified by high-performance liquid chromatography (HPLC) to greater than 95% purity. The purity and molecular weight of the respective peptides were confirmed by matrix-assisted laser desorption ionization (MALDI)-time of flight mass spectrometry. Left panels: HPLC profile, right panels: mass spectrum. A) L-BMAP-28, purity 95.61%; B) D-BMAP-28, purity 96.67%; C) RI-BMAP-28, purity 95.62%; D) Scrambled-BMAP-28, purity 95.34%.</p

Cohen's d, 95% confidence intervals of the original and replication studies and their combination.

<p>Unpaired t-tests untreated vs treated indicated significance, where *p<0.05, **p<0.005, ***p<0.0005. The combined study p-values were generated using Fisher's combined probability test. The Forest plot was generated using GraphPad Prism version 6.</p

Promastigote viability assay of <i>Leishmania major</i> when treated with 0.5 µM or 2 µM BMAP-28 variants.

<p><i>L. major</i> MHOM/SN/74/SD strain was treated with L-, RI- and D-BMAP-28 peptides for 4 hours. Viability was expressed as a percentage of untreated control cells. Three complete biological replicates were performed and the mean and standard deviation are shown. The percentage viability at 0.5 µM or 2 µM of each BMAP-28 peptide was calculated from the dose response curve performed (replication). The percentage viability at 0.5 µM or 2 µM of each BMAP-28 peptide was determined from the bar graph reported in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114614#pone-0114614-g001" target="_blank">Fig. 1A</a> of Lynn <i>et al</i>. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114614#pone.0114614-Lynn1" target="_blank">[5]</a> (original). Unpaired t-tests untreated vs treated indicated significance.</p><p>Promastigote viability assay of <i>Leishmania major</i> when treated with 0.5 µM or 2 µM BMAP-28 variants.</p