On the Rapid Oxidation of Allene-Containing Phosphines

Allene-containing phosphines have recently been shown to serve as effective ligands in transition metal-catalyzed enantioselective reactions. Surprisingly, (2-allenylphenyl)­diphenyl phosphines rapidly oxidize when exposed to air, whereas many other triaryl phosphines are stable under ambient conditions. Here we describe experiments designed to understand the origin of this behavior. Stereochemical probes and an isolated phosphonium complex support the hypothesis that phosphines can cyclize onto pendant allenes and that the resultant zwitterion undergoes rapid oxidation with molecular oxygen

Charting value creation strategies B2B salespeople use throughout the sales process: learning from social media influencers

PurposeThis paper aims to explore how business-to-business (B2B) salespeople use social media and emulate value creation strategies used by social media influencers.Design/methodology/approachUsing 28 interviews with salespeople, this paper develops six propositions and a conceptual framework that outlines when and how B2B salespeople use social media in value-creating sales.FindingsThis study’s findings provide a critical analysis of when social media are most effective and beneficial in supporting salespeople’s value-creating sales in various stages in the sales process (e.g. prospecting, opening relationships, qualifying prospects and serving accounts) and when they are less effective (e.g. presenting sales messages and closing sales).Research limitations/implicationsThis research yields a substantive understanding of the evolving role that social media play in B2B sales by examining B2B salespeople’s value creation strategies through the lens of social media influencers’ practice and outlines ideas for future research on B2B salespeople’s social media strategies.Practical implicationsThe findings of this research can be used by B2B organizations to structure the training of B2B salespeople to use social media to the fullest extent by aligning specific strategies with different parts of the sales process.Originality/valueThis paper contributes by summarizing the B2B sales literature on social media and integrating recent insights from the social media influencer literature; empirically identifying how B2B salespeople use social media to create value, thus validating previous findings and extending understanding by offering a set of six theoretical propositions; and delineating B2B salespeople’s social media practice into 11 value creation strategies that are critically explored for their place in the sales process.</p

Data from: The efficacy and safety of bevacizumab plus erlotinib versus bevacizumab or erlotinibalone in the treatment of non-small-cell lung cancer: a systematic review and meta-analysis

Data from: The efficacy and safety of bevacizumab plus erlotinib versus bevacizumab or erlotinibalone in the treatment of non-small-cell lung cancer: a systematic review and meta-analysi

Mito-TEMPO ameliorates hyperthermia-impaired platelet function.

<p>(A) Platelet aggregation was performed as described in Methods. Representative traces from three independent experiments are shown. (B and C) Washed platelets were incubated at the indicated temperatures for 3 h (B), or pre-incubated with Mito-TEMPO, GM6001 and solvent control at 37°C for 15 min, followed by incubation at 42°C for 3 h (C). Western blot was performed as described in Methods. (D and E) Washed platelets were incubated at indicated temperatures for 3 h (D), or pre-incubated without (control) or with Mito-TEMPO and solvent at 37°C for 15 min, and then incubated at 42°C for 3 h (E). Platelet adhesion was performed as described in Methods. The results shown are the mean ± SEM of cell number/mm². *<i>P</i><0.017 (after Bonferroni correction) as compared with RT, **<i>P</i><0.025 (after Bonferroni correction) as compared with control. Mito-TEMPO is labeled as TEMPO.</p

Hyperthermia increase mitochondrial superoxide production.

<p>(A and B) MitoSOX^TM Red-loaded platelets were incubated at the indicated temperatures for 3 h (A) or1-3 h (B). As a positive control, loaded platelets were incubated with antimycin A at 37°C for 30 min. Samples were then analyzed by flow cytometry. Representative flow cytometric histogram is shown (A). Data are expressed as a percentage of platelets which were incubated at RT for 1h (B). Percentage of RT 1h is presented as mean ± SEM from three independent experiments. *<i>P</i><0.017 (after a Bonferroni correction) compared with RT 1 h, **<i>P</i><0.017 (after Bonferroni correction) as compared with RT 2 h, #<i>P</i><0.017 (after Bonferroni correction) as compared with RT 3 h. (C) MitoSOX^TM Red-loaded platelets were pre-incubated with apocynin, Mito-TEMPO, L-NAME, ETYA, or solvent control at 37°C for 15 min, and then incubated for 3 h at 40°C or 42°C, and further analyzed by flow cytometry. Data are expressed as a percentage of platelets that were pre-incubated with solvent control at 37°C for 15 min and then incubated at 40°C for 3 h. Percentage of 40°C platelets pre-incubated with solvent control is presented as mean ± SEM from three independent experiments. *<i>P</i><0.013 (after Bonferroni correction) as compared with solvent control at 40°C, **<i>P</i><0.013 (after Bonferroni correction) as compared with solvent control at 42°C. Antimycin A is labeled as Ant.</p

Effect of Mito-TEMPO on caspase-3 activation, depolarization of ΔΨm, and PS exposure in hyperthermia-treated platelets.

<p>(A and B) Washed platelets were incubated at indicated temperatures for 3 h (A) or pre-incubated with Mito-TEMPO and solvent control at 37°C for 15 min and then incubated at 42°C for 3 h (B). Treated platelets were lysed and analyzed by Western blot with anti-cleaved p17 fragment of caspase-3. Actin levels were assayed to demonstrate equal protein loading. Representative results of three independent experiments are presented. (C–F) Washed platelets were pre-incubated without (C and D) or with Mito-TEMPO and solvent control at 37°C for 15 min (E and F), and then incubated at the indicated temperature for 3 h. Treated platelets were incubated with TMRE (C and E), or annexin V-FITC (D and F), and analyzed by flow cytometry. Representative flow cytometric histograms are shown (C and D). Data are expressed as a percentage of platelets that were pre-incubated with solvent control at 37°C for 15 min and then incubated at RT for 3 h (E and F). The percentage of RT platelets pre-incubated with solvent is presented as mean ± SEM from three independent experiments. *<i>P</i><0.05 as compared with solvent control at an identical temperature.</p

Effect of Mito-TEMPO on Bax mitochondrial translocation and cytochrome C release in hyperthermia-treated platelets.

<p>(A–D) Washed platelets were incubated at different temperatures for 3 h (A and B), or pre-incubated with Mito-TEMPO and solvent control at 37°C for 15 min and then incubated at 42°C for 3 h (C and D). Treated platelets were lysed, and cytosol and mitochondrial fractions were isolated and analyzed by Western blot with anti-Bax (A and C), and anti-cytochrome C (B and D). Cytochrome C oxidase subunit 1 (COX1) and tubulin were used as internal controls. Representative data of three independent experiments are presented. Cytochrome C is labeled as Cyto C.</p

Mitochondria are the major sources of ROS in hyperthermia-treated platelets.

<p>(A and B) DCFDA-loaded platelets were incubated at the indicated temperatures for 3 h (A) or 1-3 h (B). As a positive control, loaded platelets were incubated with thrombin at 37°C for 30 min. Samples were then analyzed for intracellular ROS levels by flow cytometry. Representative flow cytometric histogram is shown (A). The relative ROS levels are expressed as a percentage of platelets, which were incubated at RT for 1 h (B). Percentage of RT 1h is presented as mean ± SEM from three independent experiments. *<i>P</i><0.017 (after Bonferroni correction) as compared with RT 1 h, **<i>P</i><0.017 (after Bonferroni correction) as compared with RT 2 h, #<i>P</i><0.017 (after Bonferroni correction) as compared with RT 3h. (C–E) DCFDA-loaded platelets were pre-incubated with solvent control, DPI and apocynin (C), Mito-TEMPO and NAC (D), or L-NAME and ETYA (E) at 37 °C for 15 min, and then incubated for 3 h at 40°C or 42°C, and further analyzed by flow cytometry. The relative ROS levels are expressed as a percentage of platelets, which were pre-incubated with solvent control at 37°C for 15 min and then incubated at 40°C for 3 h. Percentage of 40°C loaded platelets pre-incubated with solvent control is presented as mean ± SEM from three independent experiments. *<i>P</i><0.025 (after Bonferroni correction) as compared with solvent control at 40°C, **<i>P</i><0.025 (after Bonferroni correction) as compared with solvent control at 42°C. Thrombin is labeled as Thr.</p

Chiral Allene-Containing Phosphines in Asymmetric Catalysis

We demonstrate that allenes, chiral 1,2-dienes, appended with basic functionality can serve as ligands for transition metals. We describe an allene-containing bisphosphine that, when coordinated to Rh(I), promotes the asymmetric addition of arylboronic acids to α-keto esters with high enantioselectivity. Solution and solid-state structural analysis reveals that one olefin of the allene can coordinate to transition metals, generating bi- and tridentate ligands

PONE-D-15-00619R1_FTC

PONE-D-15-00619R1_FT