How Do Behavioral Framing, Linguistic Certainty, and Target Specification Impact Responses to Vaping Prevention Messages?

While research on youth vaping prevention has begun to grow, little work has examined language choice in vaping prevention messages. This study examined adolescents' responses to vaping prevention statements that varied on three features: behavioral framing, linguistic certainty, and target specification. We conducted a 2 (behavioral framing) by 2 (linguistic certainty) by 2 (target specification) by 3 (risk type) plus control condition between-subjects experiment using a national probability sample. Adolescents (N = 1,603) were randomly assigned to one of 25 conditions in which they viewed a vaping prevention statement (or a control statement about vape litter) followed by measures of perceived message effectiveness (PME), perceived severity and susceptibility of vaping risks, message trustworthiness, message relevance, and intentions to seek more information about vaping risks. Results showed main effects of behavioral framing, such that a declarative frame ("Vaping can … ") led to higher PME, higher perceived severity, and greater information seeking intentions than a contingent frame ("If you vape, it can…"), while an interaction revealed that most declarative frame effects were driven by adolescents who were susceptible to vaping. There were also main effects of linguistic certainty, such that the word "can" ("Vaping can … ") led to higher PME, higher perceived susceptibility and severity, and greater information seeking intentions than the word "could" ("Vaping could … "). No main effect of target specification ("you" vs. "teens") was observed. Overall, findings suggest that vaping prevention messages that communicate greater certainty have greater behavior change potential.

Identifying promising themes and messages for youth vaping prevention: A national study.

Use of e-cigarettes and vapes among adolescents continues to be a major public health concern. Health communication efforts can discourage e-cigarette use among adolescents by influencing beliefs and behavior. However, to do so, studies need to identify the most promising themes and messages based on the latest evidence about the harms of e-cigarettes and vaping. Participants were a nationally representative sample of 1,603 US adolescents aged 13-17 years, recruited in the summer of 2022. Adolescents were randomly assigned to view 7 vaping prevention statements (one from each theme: nicotine addiction, chemical harms, health symptoms, mental health, organ effects, cosmetic effects, and monetary cost) and 1 control statement (vape litter theme) from a pool of 46 statements that were developed through a systematic process. Participants rated each statement on perceived message effectiveness (PME), awareness, and believability. Results of linear mixed models indicated that all vaping prevention themes out-performed control messages on PME, with chemical harms and organ effects having the largest effects, followed by nicotine addiction and then other themes. For most message themes, PME effects were stronger for youth susceptible to vaping compared to non-susceptible youth and users. Both awareness and believability predicted higher levels of PME. In secondary analyses, we found that statements specifying the target ("you") and longer statements were also rated higher on PME. Results suggests that the most potent vaping prevention messages for adolescents are those that focus on vape chemicals and the potential of vaping to damage organs and increase disease risk.

Awareness and Perceptions of US Food and Drug Administration's JUUL Marketing Denial Order: A National Study of US Adolescents.

INTRODUCTION: We examined awareness and perceptions of the US Food and Drug Administration (FDA) JUUL marketing denial order (MDO) that occurred in June 2022 among a nationally representative sample of US adolescents. AIMS AND METHODS: Data were collected in August 2022 via an online survey (n = 1603). Adolescents were asked whether they had heard about the JUUL MDO, and, if yes, where they heard the news. Those who had heard were asked about the MDO's impact on their harm beliefs about JUUL and vape products in general. We examined correlates of awareness of the MDO and of increased JUUL and vape harm perceptions. RESULTS: Twenty-seven percent of adolescents had heard about the MDO. Older adolescents (adjusted odds ratio [aOR] = 1.13) and LGBTQ+ adolescents (aOR = 2.05) had significantly higher odds of having heard the news, while those who identified as Black or African American had significantly lower odds of having heard (aOR = 0.56). Most participants who were aware of the MDO indicated that they had higher harm perceptions about JUUL itself (77.9%) and vapes in general (79.6%). Youths susceptible to vaping and current users were less likely to report increased harm perceptions about JUUL (B = -0.34 and -0.46, respectively) and vapes in general (B = -0.27 and -0.43) compared with youth not susceptible to vaping. CONCLUSIONS: The results of this nationally representative survey demonstrate that over one-quarter of US youth heard about the JUUL MDO and the vast majority of those indicated increased harm perceptions about vapes. Large-scale news events about vaping can reach youth audiences and may impact what youth think about the harms of vaping. IMPLICATIONS: Analysis of a nationally representative survey of adolescents aged 13-17 revealed that more than 25% had heard about the marketing denial order issued to JUUL Labs by the FDA in June of 2022. We also found that the vast majority of adolescents reported increased JUUL and vape harm perceptions in response to hearing about the MDO. This indicates that news coverage about vaping-including coverage of regulatory actions-can reach and potentially impact adolescents. It is therefore important to monitor news coverage about vaping, how it is framed and discussed across media platforms, and its reach among priority populations.

Synthetic nicotine descriptors: awareness and impact on perceptions of e-cigarettes among US youth.

BACKGROUND: Electronic cigarettes (e-cigarettes) are being advertised and sold with synthetic nicotine. Little research has examined youth awareness of synthetic nicotine or the impact of synthetic nicotine descriptors on perceptions of e-cigarettes. METHODS: Participants were a sample of 1603 US adolescents (aged 13-17 years) from a probability-based panel. The survey assessed knowledge of nicotine source in e-cigarettes (from 'tobacco plants' or 'other sources besides tobacco plants') and awareness of e-cigarettes containing synthetic nicotine. Then, in a between-subjects experiment with a 2×3 factorial design, we manipulated descriptors on e-cigarette products: (1) nicotine label (inclusion of the word 'nicotine': present or absent) and (2) source label (inclusion of a source: 'tobacco-free', 'synthetic' or absent). RESULTS: Most youth were either unsure (48.1%) or did not think (20.2%) that nicotine in e-cigarettes comes from tobacco plants; similarly, most were unsure (48.2%) or did not think (8.1%) that nicotine in e-cigarettes comes from other sources. There was low-to-moderate awareness of e-cigarettes containing synthetic nicotine (28.7%), with higher awareness among youth who use e-cigarettes (48.0%). While no main effects were observed, there was a significant three-way interaction between e-cigarette status and the experimental manipulations. The 'tobacco-free nicotine' descriptor increased purchase intentions relative to 'synthetic nicotine' (simple slope: 1.20, 95% CI 0.65 to 1.75) and 'nicotine' (simple slope: 1.20, 95% CI 0.67 to 1.73) for youth who use e-cigarettes. CONCLUSIONS: Most US youth do not know or have incorrect beliefs about the sources of nicotine in e-cigarettes and describing synthetic nicotine as 'tobacco-free nicotine' increases purchase intentions among youth who use e-cigarettes.

A randomized, controlled trial of Veriset™ hemostatic patch in halting cardiovascular bleeding.

BACKGROUND: Obtaining hemostasis during cardiovascular procedures can be a challenge, particularly around areas with a complex geometry or that are difficult to access. While several topical hemostats are currently on the market, most have caveats that limit their use in certain clinical scenarios such as pulsatile arterial bleeding. The aim of this study was to assess the effectiveness and safety of Veriset™ hemostatic patch in treating cardiovascular bleeding. METHODS: Patients (N=90) scheduled for cardiac or vascular surgery at 12 European institutions were randomized 1:1 to treatment with either Veriset™ hemostatic patch (investigational device) or TachoSil® (control). After application of the hemostat, according to manufacturer instructions for use, time to hemostasis was monitored. Follow-up occurred up to 90 days post-surgery. RESULTS: Median time to hemostasis was 1.5 min with Veriset™ hemostatic patch, compared to 3.0 min with TachoSil® (p<0.0001). Serious adverse events within 30 days post-surgery were experienced by 12/44 (27.3%) patients treated with Veriset™ hemostatic patch and 10/45 (22.2%) in the TachoSil® group (p=0.6295). None of these adverse events were device-related, and no reoperations for bleeding were required within 5 days post-surgery in either treatment group. CONCLUSION: This study reinforces the difference in minimum recommended application time between Veriset™ hemostatic patch and TachoSil® (30 s versus 3 min respectively). When compared directly at 3 min, Veriset™ displayed no significant difference, showing similar hemostasis and safety profiles on the cardiovascular bleeding sites included in this study.

N-Heterocyclic Carbene Capture by Cytochrome P450 3A4.

Cytochrome P450 3A4 (CYP3A4) is the dominant P450 enzyme involved in human drug metabolism, and its inhibition may result in adverse interactions or, conversely, favorably reduce the systemic elimination rates of poorly bioavailable drugs. Herein we describe a spectroscopic investigation of the interaction of CYP3A4 with N-methylritonavir, an analog of ritonavir, widely used as a pharmacoenhancer. In contrast to ritonavir, the binding affinity of N-methylritonavir for CYP3A4 is pH-dependent. At pH <7.4, the spectra are definitively type I, whereas at pH ≥7.4 the spectra have split Soret bands, including a red-shifted component characteristic of a P450-carbene complex. Variable-pH UV-visible spectroscopy binding studies with molecular fragments narrows the source of this pH dependence to its N-methylthiazolium fragment. The C2 proton of this group is acidic, and variable-pH resonance Raman spectroscopy tentatively assigns it a pKa of 7.4. Hence, this fragment of N-methylritonavir is expected to be readily deprotonated under physiologic conditions to yield a thiazol-2-ylidene, which is an N-heterocyclic carbene that has high-affinity for and is presumed to be subsequently captured by the heme iron. This mechanism is supported by time-dependent density functional theory with an active site model that accurately reproduces distinguishing features of the experimental UV-visible spectra of N-methylritonavir bound to CYP3A4. Finally, density functional theory calculations support that this novel interaction is as strong as the tightest-binding azaheterocycles found in P450 inhibitors and could offer new avenues for inhibitor development.

Spin equilibrium and O2-binding kinetics of Mycobacterium tuberculosis CYP51 with mutations in the histidine-threonine dyad.

The acidic residues of the "acid-alcohol pair" in CYP51 enzymes are uniformly replaced with histidine. Herein, we adopt the Mycobacterium tuberculosis (mt) enzyme as a model system to investigate these residues' roles in finely tuning the heme conformation, iron spin state, and formation and decay of the oxyferrous enzyme. Properties of the mtCYP51 and the T260A, T260V, and H259A mutants were interrogated using UV-Vis and resonance Raman spectroscopies. Evidence supports that these mutations induce comprehensive changes in the heme environment. The heme iron spin states are differentially sensitive to the binding of the substrate, dihydrolanosterol (DHL). DHL and clotrimazole perturb the local environments of the heme vinyl and propionate substituents. Molecular dynamics (MD) simulations of the DHL-enzyme complexes support that the observed perturbations are attributable to changes in the DHL binding mode. Furthermore, the rates of the oxyferrous formation were measured using stopped-flow methods. These studies demonstrate that both HT mutations and DHL modulate the rates of oxyferrous formation. Paradoxically, the binding rate to the H259A mutant-DHL complex was approximately four-fold that of mtCYP51, a phenomenon that is predicted to result from the creation of an additional diffusion channel from loss of the H259-E173 ion pair in the mutant. Oxyferrous enzyme auto-oxidation rates were relatively constant, with the exception of the T260V-DHL complex. MD simulations lead us to speculate that this behavior may be attributed to the distortion of the heme macrocycle by the substrate.

Abnormal neurites containing C-terminally truncated alpha-synuclein are present in Alzheimer's disease without conventional Lewy body pathology.

The pathological hallmark of Parkinson's disease and diffuse Lewy body disease (DLBD) is the aggregation of α-synuclein (α-syn) in the form of Lewy bodies and Lewy neurites. Patients with both Alzheimer's disease (AD) and cortical Lewy pathology represent the Lewy body variant of AD (LBV) and constitute 25% of AD cases. C-terminally truncated forms of α-syn enhance the aggregation of α-syn in vitro. To investigate the presence of C-terminally truncated α-syn in DLBD, AD, and LBV, we generated and validated polyclonal antibodies to truncated α-syn ending at residues 110 (α-syn110) and 119 (α-syn119), two products of 20S proteosome-mediated endoproteolytic cleavage. Double immunofluorescence staining of the cingulate cortex showed that α-syn110 and α-syn140 (full-length) aggregates were not colocalized in LBV. All aggregates containing α-syn140 also contained α-syn119; however, some aggregates contained α-syn119 without α-syn140, suggesting that α-syn119 may stimulate aggregate formation. Immunohistochemistry and image analysis of tissue microarrays of the cingulate cortex from patients with DLBD (n = 27), LBV (n = 27), and AD (n = 19) and age-matched controls (n = 15) revealed that AD is also characterized by frequent abnormal neurites containing α-syn119. Notably, these neurites did not contain α-syn ending at residues 110 or 122-140. The presence of abnormal neurites containing α-syn119 in AD without conventional Lewy pathology suggests that AD and Lewy body disease may be more closely related than previously thought.

The pharmacophore of a peptoid VEGF receptor 2 antagonist includes both side chain and main chain residues.

Here we identify the pharmacophore in a peptoid that antagonizes Vascular Endothelial Growth Factor Receptor-2 (VEGFR2) in vitro and in vivo. Only three of the side chains in the peptoid are required for activity. Surprisingly, however, main chain atoms also form critical interactions with the receptor.

A peptoid antagonist of VEGF receptor 2 recognizes a 'hotspot' in the extracellular domain distinct from the hormone-binding site.

Antagonists of VEGF-mediated angiogenesis are of great interest clinically for the treatment of solid tumors and certain forms of macular degeneration. We recently described a novel peptoid antagonist of VEGF Receptor 2 (VEGFR2) that binds to the extracellular domain of the receptor and inhibits VEGF-mediated autophosphorylation and subsequent downstream signaling. Given the structural similarities between peptides and peptoids, an obvious model for the mode of action of the peptoid is that it competes with VEGF for binding to VEGFR2. However, we present evidence here that this is not the case and that VEGF and the peptoid antagonist recognize non-overlapping surfaces located within the first three immunoglobulin-like subdomains of the receptor. These data argue that the peptoid inhibits receptor-mediated autophosphorylation by a novel allosteric mechanism that may prevent the receptor from acquiring the conformation necessary to propagate downstream signals.

Base-Directed Formation of Fluorescent Silver Clusters.

Small silver clusters that form with short oligonucleotides are distinguished by their strong fluorescence. Previous work showed that red and blue/green emitting species form with the cytosine oligonucleotide dC12. To understand how the bases and base sequence influence cluster formation, the blue/green emitting clusters that form with the thymine-containing oligonucleotides dT12, dT4C4T4, and dC4T4C4 are discussed. With dT12 and dT4C4T4, variations in the solution pH establish that the clusters associate with the N3 of thymine. The small clusters are bound to the larger DNA template, as demonstrated by fluorescence anisotropy, circular dichroism, and fluorescence correlation spectroscopy (FCS) studies. For dT4C4T4, FCS studies showed that approximately 50% of the strands are labeled with the fluorescent clusters. Absorption spectra and the gas dependence of the fluorescence show that nonfluorescent clusters also form following the reduction of the silver cation - oligonucleotide conjugates. Fluorescent cluster formation is favored by oxygen, thus indicating that the DNA-bound clusters are partially oxidized. To elaborate the sequence dependence of cluster formation, dC4T4C4 was studied. Cluster formation depends on the oligonucleotide concentration, and higher concentrations favor a red emitting species. A blue/green emissive species dominates at lower concentrations of dC4T4C4, and it has spectroscopic, physical, and chemical properties that are similar to those of the clusters that form with dT12 and dT4C4T4. These results suggest that cytosine- and thymine-containing oligonucleotides stabilize a preferred emissive silver cluster.

Ag Nanocluster Formation Using a Cytosine Oligonucleotide Template.

The reduction of silver cations bound to the oligonucleotide dC(12) was used to form silver nanoclusters. Mass spectra show that the oligonucleotides have 2-7 silver atoms that form multiple species, as evident from the number of transitions in the fluorescence and absorption spectra. The variations in the concentrations of the nanoclusters with time are attributed to the changing reducing capacity of the solution, and the formation of oxidized nanoclusters is proposed. Via mass spectrometry and circular dichroism spectroscopy, double-stranded structures with Ag(+)-mediated interactions between the bases are observed, but these structures are not maintained with the reduced nanoclusters. Through variations in the pH, the nanoclusters are shown to bind with the N3 of cytosine.