Patterns of flavored e-cigarette use among adult vapers in the USA: an online cross-sectional survey of 69,233 participants

BACKGROUND

Flavored e-cigarettes remain a controversial topic with regulators planning or already implementing restrictions worldwide. In this study, we examined patterns of flavor use in e-cigarettes among a convenience sample of US adult vapers.

METHODS

Participants aged ≥ 18 years who reported ever using an e-cigarette were included in the study (N = 69,233) and responded to an online questionnaire. Their smoking status was recorded as well as patterns of flavor use at e-cigarette use initiation, at the time of the survey and at the time of smoking cessation (for participants who used to smoke and were using e-cigarettes at the time of quitting).

RESULTS

The most popular flavors at e-cigarette use initiation were fruit (82.8%), followed by dessert/pastry/bakery (68.6%) and candy/chocolate/sweet (52.2%). Slightly higher prevalence of using fruit and dessert/pastry/bakery flavors was observed in those who never smoked compared to those who were currently and formerly smoking. Tobacco flavors were used by 20.8% of the participants and was by far the least prevalent among participants who never smoked. Similar patterns were observed with participants' choices at the time of the survey, but tobacco flavor use was substantially reduced (7.7%). Only 2.1% reported tobacco as the single most often used flavor. The most prevalent flavor at the time of quitting smoking was again fruit (83.3%), followed by dessert/pastry/bakery (68.0%) and candy/chocolate/sweet (44.5%). These flavors were considered the most helpful for quitting smoking. Tobacco flavor use at the time of smoking cessation was reported by 15.0%, while 9.3% considered it helpful for quitting smoking.

CONCLUSION

Non-tobacco flavors were popular among the US adult vapers who participated in the study, and were popular choices at the time of quitting smoking for those who formerly smoked. Tobacco flavor use prevalence was low and was further reduced over time. Regulators should consider the flavor choice of adult consumers, especially those who quit smoking, when preparing legislation on flavored e-cigarettes.

Comparative assessment of electronic nicotine delivery systems aerosol and cigarette smoke on endothelial cell migration: The Replica Project

Cigarette smoking is associated with impairment of repair mechanisms necessary for vascular endothelium homeostasis. Reducing the exposure to smoke toxicants may result in the mitigation of the harmful effect on the endothelium and cardiovascular disease development. Previous investigations evaluated in vitro the effect of electronic cigarette (EC) compared with cigarette smoke demonstrating a significant reduction in human umbilical vein endothelial cells (HUVECs) migration inhibition following EC aerosol exposure. In the present study, we replicated one of these studies, evaluating the effects of cigarette smoke on endothelial cell migration compared with aerosol from EC and heated tobacco products (HTPs). We performed an in vitro scratch wound assay on endothelial cells with a multi-center approach (ring-study) to verify the robustness and reliability of the results obtained in the replicated study, also testing the effect of aerosol from two HTPs on endothelial cells. Consistently with the original study, we observed a substantial reduction of the effects of aerosol from EC and HTPs on endothelial cell migration compared with cigarette smoke. While cigarette smoke reduced endothelial wound healing ability already at low concentrations (12.5%) and in a concentration-dependent manner, EC and HTPs aerosol showed no effect on endothelial cells until 80%-100% concentrations. In conclusion, our study further confirms the importance of EC and tobacco heated products as a possible harm reduction strategy for cardiovascular diseases development in smokers.

PheWAS and cross-disorder analysis reveal genetic architecture, pleiotropic loci and phenotypic correlations across 11 autoimmune disorders

Introduction

Autoimmune disorders (ADs) are a group of about 80 disorders that occur when self-attacking autoantibodies are produced due to failure in the self-tolerance mechanisms. ADs are polygenic disorders and associations with genes both in the human leukocyte antigen (HLA) region and outside of it have been described. Previous studies have shown that they are highly comorbid with shared genetic risk factors, while epidemiological studies revealed associations between various lifestyle and health-related phenotypes and ADs.

Methods

Here, for the first time, we performed a comparative polygenic risk score (PRS) - Phenome Wide Association Study (PheWAS) for 11 different ADs (Juvenile Idiopathic Arthritis, Primary Sclerosing Cholangitis, Celiac Disease, Multiple Sclerosis, Rheumatoid Arthritis, Psoriasis, Myasthenia Gravis, Type 1 Diabetes, Systemic Lupus Erythematosus, Vitiligo Late Onset, Vitiligo Early Onset) and 3,254 phenotypes available in the UK Biobank that include a wide range of socio-demographic, lifestyle and health-related outcomes. Additionally, we investigated the genetic relationships of the studied ADs, calculating their genetic correlation and conducting cross-disorder GWAS meta-analyses for the observed AD clusters.

Results

In total, we identified 508 phenotypes significantly associated with at least one AD PRS. 272 phenotypes were significantly associated after excluding variants in the HLA region from the PRS estimation. Through genetic correlation and genetic factor analyses, we identified four genetic factors that run across studied ADs. Cross-trait meta-analyses within each factor revealed pleiotropic genome-wide significant loci.

Discussion

Overall, our study confirms the association of different factors with genetic susceptibility for ADs and reveals novel observations that need to be further explored.

Saline nasal irrigation and gargling in COVID-19: a multidisciplinary review of effects on viral load, mucosal dynamics, and patient outcomes

With unrelenting SARS-CoV-2 variants, additional COVID-19 mitigation strategies are needed. Oral and nasal saline irrigation (SI) is a traditional approach for respiratory infections/diseases. As a multidisciplinary network with expertise/experience with saline, we conducted a narrative review to examine mechanisms of action and clinical outcomes associated with nasal SI, gargling, spray, or nebulization in COVID-19. SI was found to reduce SARS-CoV-2 nasopharyngeal loads and hasten viral clearance. Other mechanisms may involve inhibition of viral replication, bioaerosol reduction, improved mucociliary clearance, modulation of ENaC, and neutrophil responses. Prophylaxis was documented adjunctive to personal protective equipment. COVID-19 patients experienced significant symptom relief, while overall data suggest lower hospitalization risk. We found no harm and hence recommend SI use, as safe, inexpensive, and easy-to-use hygiene measure, complementary to hand washing or mask-wearing. In view of mainly small studies, large well-controlled or surveillance studies can help to further validate the outcomes and to implement its use.

The impact of COVID-19 lockdown on children's and adolescents' mental health in Greece

The aim of the study was to investigate the impact of the COVID-19 lockdown on children's and adolescents' mental health in Greece during the lockdown of spring 2020. A cross-sectional survey of 1232 Greek parents was conducted in spring 2020. 35.1% of parents reported that their children's psychological health was significantly affected. Parental unemployment, limited opportunity for tele-work and deteriorating psychological health, increased family conflicts and children's pre-existing physical health conditions were all significantly associated with mental health impact. Children and adolescents may experience adverse mental health effects due to the COVID-19 pandemic.

Electronic nicotine delivery systems exhibit reduced bronchial epithelial cells toxicity compared to cigarette: the Replica Project

Electronic nicotine delivery systems (ENDS) may reduce health risks associated with chronic exposure to smoke and their potential benefits have been the matter of intense scientific debate. We aimed to replicate three published studies on cytotoxic and inflammatory effects of cigarette smoke and ENDS aerosol in an independent multi-center ring study. We aimed to establish the reliability of results and the robustness of conclusions by replicating the authors' experimental protocols and further validating them with different techniques. Human bronchial epithelial cells (NCI-H292) were exposed to cigarette whole smoke and vapor phase and to aerosol from ENDS. We also assessed the inflammatory cytokines interleukin-6 and interleukin-8 and the remodeling mediator matrix metalloproteinase-1. We replicated cell viability results and confirmed that almost 80% of cytotoxic effects are due to volatile compounds in the vapor phase of smoke. Our findings substantiated the reduced cytotoxic effects of ENDS aerosol. However, our data on inflammatory and remodeling activity triggered by smoke differed significantly from those in the original reports. Taken together, independent data from multiple laboratories clearly demonstrated the reduced toxicity of ENDS products compared to cigarettes.

Immune response (IgG) following full inoculation with BNT162b2 COVID‑19 mRNA among healthcare professionals

Soon after the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in December, 2019, numerous research teams, assisted by vast capital investments, achieved vaccine development in a fraction of time. However, almost 8 months following the initiation of the European vaccination programme, the need for prospective monitoring of the vaccine-induced immune response, its determinants and related side-effects remains a priority. The present study aimed to quantify the immune response following full vaccination with the BNT162b2 coronavirus disease 2019 (COVID-19) mRNA vaccine by measuring the levels of immunoglobulin G (IgG) titers in healthcare professionals. Moreover, common side-effects and factors associated with IgG titers were identified. For this purpose, blood samples from 517 individuals were obtained and analysed. Blood sampling was performed at a mean period of 69.0±23.5 days following the second dose of the vaccine. SARS-CoV-2 IgG titers had an overall mean value of 4.23±2.76. Females had higher titers than males (4.44±2.70 and 3.89 ±2.84, respectively; P=0.007), while non-smokers had higher titers than smokers (4.48±2.79 and 3.80±2.64, respectively; P=0.003). An older age was also associated with lower antibody titers (P<0.001). Moreover, the six most prevalent adverse effects were pain at the injection site (72.1%), generalized fatigue (40.5%), malaise (36.3%), myalgia (31,0%), headache (25.8%) and dizziness/weakness (21.6%). The present study demonstrated that the immune response after receiving the BNT162b2 COVID-19 mRNA vaccine is dependent on various modifiable and non-modifiable factors. Overall, the findings of the present study highlight two key aspects of the vaccination programs: First, the need for prospective immunosurveillance studies in order to estimate the duration of immunity, and second, the need to identify those individuals who are at a greater risk of developing low IgG titers in order to evaluate the need for a third dose of the vaccine.

Erratum to "COVID-19 pandemic and alcohol consumption: Impacts and interconnections" [Toxicol. Rep. 8C (2021) 529 - 535/1078]

[This corrects the article DOI: 10.1016/j.toxrep.2021.03.005.].

Myasthenia gravis genome-wide association study implicates AGRN as a risk locus

BACKGROUND

Myasthenia gravis (MG) is a rare autoimmune disorder affecting the neuromuscular junction (NMJ). Here, we investigate the genetic architecture of MG via a genome-wide association study (GWAS) of the largest MG data set analysed to date.

METHODS

We performed GWAS meta-analysis integrating three different data sets (total of 1401 cases and 3508 controls). We carried out human leucocyte antigen (HLA) fine-mapping, gene-based and tissue enrichment analyses and investigated genetic correlation with 13 other autoimmune disorders as well as pleiotropy across MG and correlated disorders.

RESULTS

We confirmed the previously reported MG association with TNFRSF11A (rs4369774; p=1.09×10^-13, OR=1.4). Furthermore, gene-based analysis revealed AGRN as a novel MG susceptibility gene. HLA fine-mapping pointed to two independent MG loci: HLA-DRB1 and HLA-B. MG onset-specific analysis reveals differences in the genetic architecture of early-onset MG (EOMG) versus late-onset MG (LOMG). Furthermore, we find MG to be genetically correlated with type 1 diabetes (T1D), rheumatoid arthritis (RA), late-onset vitiligo and autoimmune thyroid disease (ATD). Cross-disorder meta-analysis reveals multiple risk loci that appear pleiotropic across MG and correlated disorders.

DISCUSSION

Our gene-based analysis identifies AGRN as a novel MG susceptibility gene, implicating for the first time a locus encoding a protein (agrin) that is directly relevant to NMJ activation. Mutations in AGRN have been found to underlie congenital myasthenic syndrome. Our results are also consistent with previous studies highlighting the role of HLA and TNFRSF11A in MG aetiology and the different risk genes in EOMG versus LOMG. Finally, we uncover the genetic correlation of MG with T1D, RA, ATD and late-onset vitiligo, pointing to shared underlying genetic mechanisms.

Back to basics in COVID-19: Antigens and antibodies-Completing the puzzle

The outbreak of the coronavirus disease 2019 (COVID-19) has gathered 1 year of scientific/clinical information. This informational asset should be thoroughly and wisely used in the coming year colliding in a global task force to control this infection. Epidemiology of this infection shows that the available estimates of SARS-CoV-2 infection prevalence largely depended on the availability of molecular testing and the extent of tested population. Within molecular diagnosis, the viability and infectiousness of the virus in the tested samples should be further investigated. Moreover, SARS-CoV-2 has a genetic normal evolution that is a dynamic process. The immune system participates to the counterattack of the viral infection by pathogen elimination, cellular homoeostasis, tissue repair and generation of memory cells that would be reactivated upon a second encounter with the same virus. In all these stages, we still have knowledge to be gathered regarding antibody persistence, protective effects and immunological memory. Moreover, information regarding the intense pro-inflammatory action in severe cases still lacks and this is important in stratifying patients for difficult to treat cases. Without being exhaustive, the review will cover these important issues to be acknowledged to further advance in the battle against the current pandemia.

Safety of COVID-19 vaccines administered in the EU: Should we be concerned?

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mRNA and viral vector vaccines are currently used in the EU for COVID-19 prophylaxis.

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EMA has assessed the safety of the three vaccines currently used in the EU.

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Local and systemic reactions are reported during vaccinations campaigns.

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Vaccine-induced immune thrombotic thrombocytopenia has been linked to Vaxzevria.

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Follow-up and surveillance studies for vaccines’ safety monitoring will be needed.

The COVID-19 pandemic has had an unprecedented and devastating impact on public health, society and economics around the world. As a result, the development of vaccines to protect individuals from symptomatic COVID-19 infections has represented the only feasible health tool to combat the spread of the disease. However, at the same time the development and regulatory assessment of different vaccines has challenged pharmaceutical industries and regulatory agencies as this process has occurred in the shorter time ever though. So far, two mRNA and two adenovirus-vectored vaccines have received a conditional marketing authorisation in the EU and other countries. This review summarized and discusses the assessment reports of the European Medicine Agency (EMA) concerning the safety of the 3 vaccines currently used in the EU (Pfizer, Moderna and Astra-Zeneca). A particular focus has been paid to safety information from pre-clinical (animal) and clinical (phase 3 trials) studies. Overall, the most frequent adverse effects reported after the administration of these vaccines consisted of local reactions at the injection site (sore arm and erythema) followed by non-specific systemic effects (myalgia, chills, fatigue, headache, and fever), which occurred soon after vaccination and resolved shortly. Rare cases of vaccine-induced immune thrombotic thrombocytopenia have been reported for Vaxzevria. Data on long-term studies, interaction with other vaccines, use in pregnancy/breast-feeding, use in immunocompromised subjects, and in subjects with comorbidities, autoimmune or inflammatory disorders are still missing for these vaccines. Therefore, careful follow-up and surveillance studies for continued vaccine safety monitoring will be needed to ascertain the potential risks of such adverse events or diseases. In conclusion, the benefits and risks of current COVID-19 vaccines must be weighed against the real possibility of contract the disease and develop complications and long-term sequels; all this on the basis of the available scientific evidence and in the absence of unmotivated biases.

COVID-19 pandemic and alcohol consumption: Impacts and interconnections

Alcohol consumption is associated with multiple diseases and might contribute to vulnerability to SARS-CoV-2 infection. It can also catalyze exacerbations of mental and organic illnesses and predispose to behaviors with an increased risk of infection, severity of disease but also independently of sociopathic behavior and violence. Globally, millions of premature deaths from excessive alcohol consumption occur each year. This paper discusses the effects of increased alcohol consumption and the most important consequences on the health of the population during the social isolation and lockdown during current COVID-19 pandemic.

Nicotinic cholinergic system and COVID-19: In silico identification of interactions between α7 nicotinic acetylcholine receptor and the cryptic epitopes of SARS-Co-V and SARS-CoV-2 Spike glycoproteins

SARS-CoV-2 is the coronavirus that originated in Wuhan in December 2019 and has spread globally. Studies have shown that smokers are less likely to be diagnosed with or be hospitalized for COVID-19 but, once hospitalized, have higher odds for an adverse outcome. We have previously presented the potential interaction between SARS-CoV-2 Spike glycoprotein and nicotinic acetylcholine receptors (nAChRs), due to a "toxin-like" epitope on the Spike glycoprotein, with homology to a sequence of a snake venom toxin. This epitope coincides with the well-described cryptic epitope for the human anti-SARS-CoV antibody CR3022. In this study, we present the molecular complexes of both SARS-CoV and SARS-CoV-2 Spike glycoproteins, at their open or closed conformations, with the model of the human α7 nAChR. We found that all studied protein complexes' interface involves a large part of the "toxin-like" sequences of SARS-CoV and SARS-CoV-2 Spike glycoproteins and toxin binding site of human α7 nAChR. Our findings provide further support to the hypothesis about the protective role of nicotine and other cholinergic agonists. The potential therapeutic role of CR3022 and other similar monoclonal antibodies with increased affinity for SARS-CoV-2 Spike glycoprotein against the clinical effects originating from the dysregulated cholinergic pathway should be further explored.

Smoking prevalence among hospitalized COVID-19 patients and its association with disease severity and mortality: an expanded re-analysis of a recent publication

BACKGROUND

There is a lot of debate about the effects of smoking on COVID-19. A recent fixed-effects meta-analysis found smoking to be associated with disease severity among hospitalized patients, but other studies report an unusually low prevalence of smoking among hospitalized patients. The purpose of this study was to expand the analysis by calculating the prevalence odds ratio (POR) of smoking among hospitalized COVID-19 patients, while the association between smoking and disease severity and mortality was examined by random-effects meta-analyses considering the highly heterogeneous study populations.

METHODS

The same studies as examined in the previous meta-analysis were analyzed (N = 22, 20 studies from China and 2 from USA). The POR relative to the expected smoking prevalence was calculated using gender and age-adjusted population smoking rates. Random-effects meta-analyses were used for all other associations.

RESULTS

A total of 7162 patients were included, with 482 being smokers. The POR was 0.24 (95%CI 0.19-0.30). Unlike the original study, the association between smoking and disease severity was not statistically significant using random-effects meta-analysis (OR 1.40, 95%CI 0.98-1.98). In agreement with the original study, no statistically significant association was found between smoking and mortality (OR 1.86, 95%CI 0.88-3.94).

CONCLUSION

An unusually low prevalence of smoking, approximately 1/4th the expected prevalence, was observed among hospitalized COVID-19 patients. Any association between smoking and COVID-19 severity cannot be generalized but should refer to the seemingly low proportion of smokers who develop severe COVID-19 that requires hospitalization. Smokers should be advised to quit due to long-term health risks, but pharmaceutical nicotine or other nicotinic cholinergic agonists should be explored as potential therapeutic options, based on a recently presented hypothesis.

A quantitative western blot technique using TMB: Comparison with the conventional technique

Numerous molecular biological experiments performed throughout the world require the detection or quantification of a protein of interest. Western blotting is one of the most popular techniques used for this purpose and offers quantitative information with the aid of specialized software. However, its dependence on the picture that is captured, and the background and the absence of a common protocol prevent the technique from being completely quantitative. To overcome these obstacles, we present a simple and reliable assay that is similar to the regular technique, with the exception of the last stage of band visualization and quantification. We propose that small pieces of the blot that include the protein of interest can be cut and dipped in a small volume of 3,3',5,5'-tetramethylbenzidine solution, giving a colorimetric signal with linear dependence on the quantity of the protein. The reaction is stopped with H₂ SO₄ , and the signal is measured in a plate reader. This modification shows high linearity without additional costs and can be applied for both purified proteins and proteins found in a lysate. The results obtained with our proposed technique were compared with those obtained by the conventional method and proved to be more reliable.

Nicotinic cholinergic system and COVID-19: In silico evaluation of nicotinic acetylcholine receptor agonists as potential therapeutic interventions

SARS-CoV-2 infection was announced as a pandemic in March 2020. Since then, several scientists have focused on the low prevalence of smokers among hospitalized COVID-19 patients. These findings led to our hypothesis that the Nicotinic Cholinergic System (NCS) plays a crucial role in the manifestation of COVID-19 and its severe symptoms. Molecular modeling revealed that the SARS-CoV-2 Spike glycoprotein might bind to nicotinic acetylcholine receptors (nAChRs) through a cryptic epitope homologous to snake toxins, substrates well documented and known for their affinity to the nAChRs. This binding model could provide logical explanations for the acute inflammatory disorder in patients with COVID-19, which may be linked to severe dysregulation of NCS. In this study, we present a series of complexes with cholinergic agonists that can potentially prevent SARS-CoV-2 Spike glycoprotein from binding to nAChRs, avoiding dysregulation of the NCS and moderating the symptoms and clinical manifestations of COVID-19. If our hypothesis is verified by in vitro and in vivo studies, repurposing agents currently approved for smoking cessation and neurological conditions could provide the scientific community with a therapeutic option in severe COVID-19.

Improved strategies to counter the COVID-19 pandemic: Lockdowns vs. primary and community healthcare

COVID-19 pandemic mitigation strategies are mainly based on social distancing measures and healthcare system reinforcement. However, many countries in Europe and elsewhere implemented strict, horizontal lockdowns because of extensive viral spread in the community which challenges the capacity of the healthcare systems. However, strict lockdowns have various untintended adverse social, economic and health effects, which have yet to be fully elucidated, and have not been considered in models examining the effects of various mitigation measures. Unlike commonly suggested, the dilemma is not about health vs wealth because the economic devastation of long-lasting lockdowns will definitely have adverse health effects in the population. Furthermore, they cannot provide a lasting solution in pandemic containment, potentially resulting in a vicious cycle of consecutive lockdowns with in-between breaks. Hospital preparedness has been the main strategy used by governments. However, a major characteristic of the COVID-19 pandemic is the rapid viral transmission in populations with no immunity. Thus, even the best hospital system could not cope with the demand. Primary, community and home care are the only viable strategies that could achieve the goal of pandemic mitigation. We present the case example of Greece, a country which followed a strategy focused on hospital preparedness but failed to reinforce primary and community care. This, along with strategic mistakes in epidemiological surveillance, resulted in Greece implementing a second strict, horizontal lockdown and having one of the highest COVID-19 death rates in Europe during the second wave. We provide recommendations for measures that will reinstate primary and community care at the forefront in managing the current public health crisis by protecting hospitals from unnecessary admissions, providing primary and secondary prevention services in relation to COVID-19 and maintaining population health through treatment of non-COVID-19 conditions. This, together with more selective social distancing measures (instead of horizontal lockdowns), represents the only viable and realistic long-term strategy for COVID-19 pandemic mitigation.

Assessing the Direct Binding of Ark-Like E3 RING Ligases to Ubiquitin and Its Implication on Their Protein Interaction Network

The ubiquitin pathway required for most proteins’ targeted degradation involves three classes of enzymes: E1-activating enzyme, E2-conjugating enzyme, and E3-ligases. The human Ark2C is the single known E3 ligase that adopts an alternative, Ub-dependent mechanism for the activation of Ub transfer in the pathway. Its RING domain binds both E2-Ub and free Ub with high affinity, resulting in a catalytic active Ub_R-RING-E2-Ub_D complex formation. We examined potential changes in the conformational plasticity of the Ark2C RING domain and its ligands in their complexed form within the ubiquitin pathway through molecular dynamics (MD). Three molecular mechanics force fields compared to previous NMR relaxation studies of RING domain of Arkadia were used for effective and accurate assessment of MDs. Our results suggest the Ark2C Ub-RING docking site has a substantial impact on maintaining the conformational rigidity of E2-E3 assembly, necessary for the E3’s catalytic activity. In the Ub_R-RING-E2-Ub_D catalytic complex, the Ub_R molecule was found to have greater mobility than the other Ub, bound to E2. Furthermore, network-based bioinformatics helped us identify E3 RING ligase candidates which potentially exhibit similar structural modules as Ark2C, along with predicted substrates targeted by the Ub-binding RING Ark2C. Our findings could trigger a further exploration of related unrevealed functions of various other E3 RING ligases.

Larvicidal Action of Cannabidiol Oil and Neem Oil against Three Stored Product Insect Pests: Effect on Survival Time and in Progeny

SStored product pests can be detrimental to agricultural produce. As much as chemical pesticides are effective control agents, they involve several environmental and health risks. Within the framework of studies on alternative pest management methods, interest has focused on a plethora of plants whose extracts have demonstrated promising action as insecticides. Azadirachta indica and the derived neem oil have been extensively tested against many harmful insect species. In contrast, Cannabis sativa L. and its main compound, CBD, a highly concentrated cannabinoid, have not been investigated much. The present study examined the potential insecticidal activity of CBD and neem oils against 4th instar larvae of Tribolium confusum, Oryzaephilus surinamensis and Plodia interpunctella on wheat, rice and corn seeds. Treatment efficacy was expressed in terms of larval mortality. Mortality was observed in relation to dosage, time exposure intervals and product types. The results showed clear pesticidal activity for both oils, which at high doses induced significant mortality. The treatments produced significantly fewer offspring in the insect species tested than the control. The efficacy of treatment in progeny suppression was, as expected, dose dependent.

Combined Toxicity of Cannabidiol Oil with Three Bio-Pesticides against Adults of Sitophilus Zeamais, Rhyzopertha Dominica, Prostephanus Truncatus and Trogoderma Granarium

The present study investigates the interaction between cannabidiol (CBD) oil and three biopesticides: Azatin and two baculovirus formulations (Madex and Helicovex), both separately and in combination, in order to investigate their interaction against adults of four major coleopteran stored-product pests: Sitophilus zeamais (Coleoptera: Curculionidae), Rhyzopertha dominica (Coleoptera: Bostrichidae), Prostephanus truncatus (Coleoptera: Bostrichidae) and Trogoderma granarium (Coleoptera: Dermestidae). CBD, which has been understudied for its insecticidal properties, was applied at three different doses (500, 1500 and 3000 ppm). The biopesticides were administered at 1500 ppm. Interactions in the combined treatments were mathematically estimated as not synergistic and mostly competitive except for the combined treatments of CBD (1500 and 3000 ppm) with Azatin (1500 ppm) which were marked by an additive interaction. In its individual application, CBD oil generated the highest insect mortality while its effect was clearly dose-dependent. The findings reveal a promising effect of CBD oil against these coleopterans which had not been previously tested together.

Imiquimod - A toll like receptor 7 agonist - Is an ideal option for management of COVID 19

According to numerous recent publications, the COVID-19 patients have lymphopenia, higher infection-related biomarkers and several elevated inflammatory cytokines (i.e. tumor necrosis factor (TNF)-α, interleukin IL-2R and IL-6). The total number of B cells, T cells and NK cells are significantly decreased. RNA viruses, SARS-CoV-2 included, hit the innate immune system in order to cause infection, through TLRs 3, 7 and 8. Imiquimod is an immune-stimulator that activates TLR 7 and can be used to enhance the innate and adaptive immunity. Preclinical and clinical trials are proposed.

Microcurrent Stimulation Triggers MAPK Signaling and TGF-β1 Release in Fibroblast and Osteoblast-Like Cell Lines

Wound healing constitutes an essential process for all organisms and involves a sequence of three phases. The disruption or elongation of any of these phases can lead to a chronic or non-healing wound. Electrical stimulation accelerates wound healing by mimicking the current that is generated in the skin after any injury. Here, we sought to identify the molecular mechanisms involved in the healing process following in vitro microcurrent stimulation-a type of electrotherapy. Our results concluded that microcurrents promote cell proliferation and migration in an ERK 1/2- or p38-dependent way. Furthermore, microcurrents induce the secretion of transforming growth factor-beta-1 (TGF-β1) in fibroblasts and osteoblast-like cells. Interestingly, transcriptomic analysis uncovered that microcurrents enhance the transcriptional activation of genes implicated in Hedgehog, TGF-β1 and MAPK signaling pathways. Overall, our results demonstrate that microcurrents may enhance wound closure through a combination of signal transductions, via MAPK's phosphorylation, and the transcriptional activation of specific genes involved in the healing process. These mechanisms should be further examined in vivo, in order to verify the beneficial effects of microcurrents in wound or fracture healing.

Knowledge, behaviours and attitudes for human papillomavirus (HPV) prevention among educators and health professionals in Greece

OBJECTIVE

Globally, human papillomavirus (HPV) is one of the most common sexually transmitted diseases in both men and women. The objective of this study was to investigate the knowledge, attitudes, and behaviour of educators and health professionals regarding the prevention of HPV infection in Greece. The analysis of the results shows that most of the participants (44.7%) had good knowledge about the human papillomavirus, regardless of occupation.

PATIENTS AND METHODS

A cross-sectional survey was carried out with seven hundred and fifty participants. The participants completed a thirty-one-item questionnaire regarding their knowledge, attitude and behaviour towards the prevention of HPV.

RESULTS

Knowledge scores were calculated with a grading system which was designed for accurate knowledge assessment. The Score was adjusted on a scale from 0 to 100 and was divided into five levels, from Excellent to Very Bad level of total knowledge. Of all the participants, 26.4% had excellent knowledge, 44.7% had good, 23.6% had moderate, 4.7% had bad, and 4.7% had a very bad level of total knowledge. Specifically, physicians of different specialities had 80.32%, and educators 65,31 % excellent level of knowledge, respectively. Also, participants had a high degree of awareness regarding prevention and adherence to the annual Papanikolaou test (65.8%) and gynaecological exam. Despite the positive response (94.1%) in terms of vaccination of boys, and girls, as well as information on HPV vaccination, many participants themselves were not vaccinated (74.8%), nor were their children (19.7%).

CONCLUSIONS

The present study showed good level of knowledge for HPV prevention regardless of occupation and is characterized by a high degree of awareness of the usefulness of prevention in adhering to the annual Pap smear test and gynaecological examination. The study shows the need for more information workshops for healthcare professionals, because physicians and midwives had high levels of knowledge, but not excellent as expected and required due to health-related profession.

Leguminous Seeds Powder Diet Reduces the Survival and Development of the Khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae)

Chemical storage pest control is interlinked with many challenges such as environmental pollution and toxicity to humans and animals. Alternative tools are thus being increasingly researched and applied to supplement and/or substitute old-fashioned chemical means. Entomotoxic proteins, such as the lectins of leguminous seeds, have been shown to be effective alternative control agents against many serious insect pests. The objective of this work was to evaluate the effect of the flour of three leguminous seeds, Phaseolus vulgaris L. (Fabaceae) (the common bean), Vicia faba L. (Fabaceae) (the broad bean) and Glycine max L. (Fabaceae) (the soya bean), against 4th instar larvae of Trogoderma granarium Everts (Coleoptera: Curculionidae). The flours were tested at different concentrations. They all demonstrated significant effects on larval mortality, as well as they all induced a decrease in the number of larvae reaching the pupal stage. The flours of P. vulgaris and V. faba were highly insecticidal against T. granarium larvae, especially at the highest concentrations (86.7% for PV100 and 90% for VF100). Our results enrich previous findings on the entomotoxic effect of leguminous plant lectins and highlight P. vulgaris and V. faba lectins as potential alternative control agents against T. granarium.

COVID-19 and the nicotinic cholinergic system

We have read with great interest the paper by Leunget al. [1] published in the European Respiratory Journal, the correspondence by Russoet al. [2], and also the subsequent comment by the first group [3]. Both research teams are reporting increased angiotensin-converting enzyme 2 (ACE-2) expression in airways of current smokers and those with COPD, with important implications for coronavirus disease 2019 (COVID-19) patients. Since ACE-2 has been shown to be the main receptor utilised by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to enter the host cells [2], the authors conclude that nicotine is a risk factor for COVID-19. Russoet al. [2] have shown that nicotine upregulates ACE-2 through α7-nAChRs which are present in neuronal and non-neuronal cells. Leunget al. [3] provided further evidence in support of this hypothesis and propose the repurposing of α7-nAChR antagonists for the pandemic (e.g. methyllycaconitine, α-conotoxin), expecting that such treatment will alter ACE-2 expression and prevent SARS-CoV-2 entry.

The prevalence of smoking among hospitalised COVID-19 patients is low. COVID-19 manifestations could be linked to impairment of the cholinergic anti-inflammatory pathway. Nicotinic cholinergic agonists should be examined as potential therapeutic options.https://bit.ly/2zfUZ1S

Current smoking, former smoking, and adverse outcome among hospitalized COVID-19 patients: a systematic review and meta-analysis

BACKGROUND

The purpose of this study was to examine the prevalence and effects of current smoking on adverse outcomes among hospitalized COVID-19 patients.

METHODS

A systematic review of the literature (PubMed) identified 18 (from a total of 1398) relevant studies. Pooled current smoking prevalence was compared with the gender-adjusted and gender and age-adjusted, population-based expected prevalence by calculating prevalence odds ratio (POR). The association between current, compared with non-current and former, smoking and adverse outcome was examined. A secondary analysis was performed by including 12 pre-publications (30 studies in total). All analyses were performed using random-effects meta-analysis.

RESULTS

Among 6515 patients, the pooled prevalence of current smoking was 6.8% [95% confidence interval (CI): 4.8-9.1%]. The gender-adjusted POR was 0.20 (95% CI: 0.16-0.25, p < 0.001), and the gender and age-adjusted POR was 0.24 (95% CI: 0.19-0.30, p < 0.001). Current smokers were more likely to have an adverse outcome compared with non-current smokers [odds ratio (OR): 1.53, 95%CI: 1.06-2.20, p = 0.022] but less likely compared with former smokers (OR: 0.42, 95% CI: 0.27-0.74, p = 0.003). When pre-publications were added (n = 10,631), the gender-adjusted POR was 0.27 (95% CI: 0.19-0.38, p < 0.001) and the gender and age-adjusted POR was 0.34 (95% CI: 0.24-0.48, p < 0.001).

CONCLUSION

This meta-analysis of retrospective observational case series found an unexpectedly low prevalence of current smoking among hospitalized patients with COVID-19. Hospitalized current smokers had higher odds compared with non-current smokers but lower odds compared with former smokers for an adverse outcome. Smoking cannot be considered a protective measure for COVID-19. However, the hypothesis that nicotine may have a protective effect in COVID-19 that is partially masked by smoking-related toxicity and by the abrupt cessation of nicotine intake when smokers are hospitalized should be explored in laboratory studies and clinical trials using pharmaceutical nicotine products.

Grape Stem Extracts From Three Native Greek Vine Varieties Exhibit Strong Antioxidant and Antimutagenic Properties

BACKGROUND/AIM

The winemaking procedure results in the generation of stems, a by-product that is harmful to the environment. Concomitantly, stems are rich in polyphenols and, hence, they are putatively beneficial for human health.

MATERIALS AND METHODS

In this study, the grape stem extracts derived from three native Greek vine varieties, namely Mavrodaphne, Muscat and Rhoditis were examined for their chemical composition and antioxidant and antimutagenic properties using a battery of in vitro biomarkers.

RESULTS

All extracts are rich in polyphenols. Moreover, they exhibit potent antioxidant and antimutagenic properties with the extract of Mavrodaphne being the strongest in reducing the DPPH^• and O₂ ^-• radicals and the Fe³⁺ and in protecting plasmid DNA from peroxyl radical-induced oxidative modification.

CONCLUSION

Therefore, although they are serious pollutants, grape stems contain phytochemicals with important biological properties and can be used as (ingredients of) bio-functional foods to improve certain aspects of human health.

Electronic Nicotine Delivery Systems (ENDS) and Their Relevance in Oral Health

The number and popularity of electronic nicotine delivery systems (ENDS) and especially e-cigarettes (e-cigs) have been increasing in the last decade. Although ENDS owe their popularity to excluding the harmful chemicals that are present in tobacco smoke, there is a debate whether they are safe, regulated, and as harmless as they are assumed to be and have potential unknown long-term effects. Involvement of cigarette smoking to the progression of periodontal diseases, other adverse oral health outcomes, and its detrimental effects to oral health are well-described. ENDS producer companies claim that these products can improve oral health by providing alternatives to smoking. However, the effect of e-cigs on oral health is not fully understood and is still debated among many scientists and clinicians. The number of studies addressing the potential toxic effect of ENDS or e-cig aerosol on oral cells is limited along with the clinical studies which are still preliminary, and their sample size is limited. The long-term effects of inhaled aerosols and the potential synergistic effect of the e-cigs components are not known. It is essential and of utmost importance to determine whether exposure to ENDS aerosol contributes to the progression of periodontal diseases and how it affects periodontal ligament and gingival cells which are believed to be its first targets. This review briefly summarizes the available evidence about the effects of e-cigs on periodontal health including several pathophysiological events, such as oxidative stress, DNA damage, inflammation, cellular senescence, dysregulated repair, and periodontal diseases.

In vivo quantification and pharmacokinetic studies of cotinine in mice after smoke exposure by LC-MS/MS

A sensitive analytical method was developed and validated for the quantification of cotinine in mouse plasma after exposure to smoke of 0.5, 1.0, and 1.5 commercially available cigarettes, using liquid chromatography tandem mass spectrometry. The method was validated over a linear concentration range of 0.075-20.0 ng/mL with the R² value being higher than 0.99. Both the precision (coefficient of variation; %) and accuracy (relative error; %) were within acceptable criteria of <15%. The lower limit of quantification (LLOQ) for cotinine was 0.075 ng/mL with sufficient specificity, accuracy, and precision. Following exposure to 0.5, 1.0, and 1.5 cigarette smoke, it was observed that the AUC and the C_max increased linearly as the doses increased. The pharmacokinetics of cotinine was found linear for the range of 0.5-1.5 commercial cigarette smoke. The quantification of the concentration of cotinine in mouse plasma after smoke exposure will facilitate future behavioral and toxicological experiments in animals and may prove useful in predicting cotinine levels in humans during smoking.

Changes in Puffing Topography and Nicotine Consumption Depending on the Power Setting of Electronic Cigarettes

Introduction

The study purpose was to evaluate changes in puffing topography of experienced electronic cigarette users (vapers) when changing power settings in electronic cigarette battery devices.

Methods

Experienced adult vapers (n = 21) were recruited. Participants used their own liquids and an atomizer and battery provided by the researchers. Two 30-minute sessions were performed, with the device power set at 6 W and 10 W, in a randomized, crossover, participant-blinded design. Puff number and duration (mean [SD]) were recorded in the provided electronic cigarette battery device, whereas the atomizers were weighted before and after use to determine liquid and nicotine consumption.

Results

Puff number and puff duration were lower at 10 W (46 [16] puffs and 3.8 [0.8] s) compared with 6 W (57 [20] puffs and 4.6 [1.0] s). Liquid and nicotine consumption was higher at 10 W (373 [176] mg and 4.2 [2.4] mg, respectively) compared with 6 W (308 [165] mg and 3.5 [2.3] mg, respectively). Vapers reported more aerosol volume and ease of use at 10 W compared with 6 W.

Conclusions

The study identified an attempt for compensatory puffing patterns and nicotine self-titration, with a change in puffing patterns (puff number and duration) observed when changing the power settings of an e-cigarette device.

Implications

Compensatory smoking behavior and nicotine self-titration is a well-established phenomenon. In electronic cigarettes, changing nicotine concentration in the liquid has been shown to trigger a compensatory puffing pattern. Herein, power setting of the electronic cigarette device was found to be a parameter associated with changes in puffing behavior, whereas higher power was preferable for the participants. These findings could contribute to the understanding of patterns of electronic cigarette use and could explain the preference of dedicated vapers to higher power devices. Additionally, laboratory studies evaluating aerosol emissions should consider using different puffing patterns according to the power settings tested.

E-cigarette use is strongly associated with recent smoking cessation: an analysis of a representative population sample in Greece

The purpose was to examine the association between e-cigarette use and smoking cessation according to quit duration in Greece in 2017. A cross-sectional survey of a representative sample of adults living in Attica prefecture was performed in May 2017 through telephone interviews. The present analysis was confined to current and former smokers (n = 2568). Logistic regression analyses were performed with current and current daily e-cigarette use being the dependent variables and demographics and smoking status (current smokers vs smoking cessation for ≤ 12 months, 13-36 months, 36-72 months, and > 72 months) being independent variables. Almost half of former smokers (47.7%) had quit smoking for ≤ 72 months. Current e-cigarette use was more prevalent among former smokers of ≤ 12 months (26.2%) and 13-36 months (27.0%), and was rare among former smokers of > 72 months (1.0%). Current e-cigarette use was strongly associated with smoking cessation for ≤ 12 months (OR 6.12, 95% CI 4.11-9.10, P < 0.001) and 13-36 months (OR 6.28, 95% CI 4.25-9.28, P < 0.001). Current daily e-cigarette use was also strongly associated with smoking cessation for ≤ 12 months (OR 10.41, 95% CI 6.56-16.53, P < 0.001) and 13-36 months (OR 11.18, 95% CI 7.12-17.55, P < 0.001). Current and current daily e-cigarette use were not significantly associated with smoking cessation for 37-72 months, and were negatively associated with smoking cessation for > 72 months. Current and current daily e-cigarette use are strongly associated with recent smoking cessation in Greece, suggesting a positive public health impact in a country with the highest prevalence of smoking in the European Union. E-cigarettes do not appear to promote relapse in long term former smokers. Duration of smoking cessation and frequency of e-cigarette use should be taken into consideration when examining the association between e-cigarette use and smoking cessation in population studies.

Carbonyl emissions from a novel heated tobacco product (IQOS): comparison with an e-cigarette and a tobacco cigarette

AIMS

To measure carbonyl emissions from a heated tobacco product (IQOS) in comparison with an e-cigarette (Nautilus Mini) and a commercial tobacco cigarette (Marlboro Red).

DESIGN

Regular and menthol variants of the heated tobacco product were tested. A tank-type atomizer was tested with a tobacco-flavoured liquid at 10 and 14 W. Aerosol and smoke were collected in impingers containing 2,4-dinitrophenylhydrazine. Health Canada Intense and two more intense puffing regimens were used.

SETTING

Analytical laboratory in Greece.

MEASUREMENTS

Carbonyl levels in the aerosol and smoke.

FINDINGS

At the Health Canada Intense regimen, heated tobacco products emitted 5.0-6.4 μg/stick formaldehyde, 144.1-176.7 μg/stick acetaldehyde, 10.4-10.8 μg/stick acrolein, 11.0-12.8 μg/stick propionaldehyde and 1.9-2.0 μg/stick crotonaldehyde. Compared with the tobacco cigarette, levels were on average 91.6% lower for formaldehyde, 84.9% lower for acetaldehyde, 90.6% lower for acrolein, 89.0% lower for propionaldehyde and 95.3% lower for crotonaldehyde. The e-cigarette emitted 0.5-1.0 μg/12 puffs formaldehyde, 0.8-1.5 μg/12 puffs acetaldehyde and 0.3-0.4 μg/12 puffs acrolein, but no propionaldehyde and crotonaldehyde. At more intense puffing regimens, formaldehyde was increased in heated tobacco products, but levels were three-fourfold lower compared with the tobacco cigarette. Based on the findings from Health Canada Intense puffing regimen, use of 20 heated tobacco sticks would result in approximately 85% to 95% reduced carbonyl exposure compared with smoking 20 tobacco cigarettes; the respective reduction in exposure from use of 5 g e-cigarette liquid would be 97% to > 99%.

CONCLUSIONS

The IQOS heated tobacco product emits substantially lower levels of carbonyls than a commercial tobacco cigarette (Marlboro Red) but higher levels than a Nautilus Mini e-cigarette.

Tobacco-specific nitrosamines: A literature review

Cigarette smoke is a complex mixture of chemicals, including several tobacco-specific nitrosamines (TSNA). Most TSNA are formed in tobacco during the post-harvest period, while a number are produced when a cigarette is burned. Considerable evidence supports the role of TSNA important causative factors for cancers of the lung, pancreas, esophagus, and oral cavity in people who use tobacco products. Of the known TSNA, nicotine-derived nitrosamine ketone (NNK) and N-nitrosonornicotine (NNN) are the most carcinogenic. Other TSNA include N'-nitrosoanatabine (NAT) and N-nitrosoanabasine (NAB). New tobacco products (e.g., e-cigarettes) designed to attract consumers who are concerned about the health effects of tobacco have been appearing on the market. Several studies have reported that certain TSNA have been detected in the replacement liquids and vapour of e-cigarettes, but the levels are generally considerably lower than in tobacco cigarettes. Additionally, the FDA recently announced its intention to regulate TSNA in e-cigarettes, cigar tobacco and pipe tobacco. With the rise of new technologies for reducing the use of tobacco products-such as e-cigarettes- to evaluate exposure levels to these harmful chemicals over time, researchers will be monitoring levels of TSNA in the body as a result of the use of these devices.

Evidence for association of STAT4 and IL12RB2 variants with Myasthenia gravis susceptibility: What is the effect on gene expression in thymus?

Myasthenia gravis (MG) is an autoimmune disease mediated by the presence of autoantibodies that bind mainly to the acetylcholine receptor (AChR) in the neuromuscular junction. In our case-control association study, we analyzed common variants located in genes of the IL12/STAT4 and IL10/STAT3 signaling pathways. A total of 175 sporadic MG patients of Greek descent, positively detected with anti-AChR autoantibodies and 84 ethnically-matched, healthy volunteers were enrolled in the study. Thymus samples were obtained from 16 non-MG individuals for relative gene expression analysis. The strongest signals of association were observed in the cases of rs6679356 between the late-onset MG patients and controls and rs7574865 between early-onset MG and controls. Our investigation of the correlation between the MG-associated variants and the expression levels of each gene in thymus did not result in significant differences.

Detection and quantitative determination of heavy metals in electronic cigarette refill liquids using Total Reflection X-ray Fluorescence Spectrometry

Electronic cigarettes are considered healthier alternatives to conventional cigarettes containing tobacco. They produce vapor through heating of the refill liquids (e-liquids) which consist of propylene glycol, vegetable glycerin, nicotine (in various concentrations), water and flavoring agents. Heavy metals may enter the refill liquid during the production, posing a risk for consumer's health due to their toxicity. The objective of the present study was the development of a methodology for the detection and quantitative analysis of cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), arsenic (As) and chromium (Cr), employing Total Reflection X-Ray Fluorescence Spectroscopy (TXRF) as an alternative technique to ICP-MS or ICP-OES commonly used for this type of analysis. TXRF was chosen due to its advantages, which include short analysis time, promptness, simultaneous multi-element analysis capability and minimum sample preparation, low purchase and operational cost. The proposed methodology was applied to a large number of electronic cigarette liquids commercially available, as well as their constituents, in order to evaluate their safety. TXRF may be a valuable tool for probing heavy metals in electronic cigarette refill liquids to serve for the protection of human health.

Electronic cigarette use in Greece: an analysis of a representative population sample in Attica prefecture

Background

The purpose was to assess prevalence and correlates of electronic cigarette (e-cigarette) use in Greece in 2017.

Methods

A cross-sectional survey of a representative sample of 4058 adults living in Attica prefecture (35% of the Greek adult population) was performed in May 2017 through telephone interviews. Prevalence and frequency of e-cigarette use were assessed according to the smoking status, and logistic regression analysis was performed to identify correlates of use.

Results

Current smoking was reported by 32.6% of participants. Ever e-cigarette use was reported by 54.1% (51.4–56.8%) of current smokers, 24.1% (21.7–26.5%) of former smokers and 6.5% (5.3–7.7%) of never smokers. Past experimentation was the most prevalent pattern of e-cigarette use among ever users (P < 0.001). Almost 80% of ever and 90% of current e-cigarette users were using nicotine. Extrapolated to the whole Attica population (3.1 million), there were 1 million current smokers, 848,000 ever e-cigarette users and 155,000 current e-cigarette users. The majority of current e-cigarette users (62.2%) were former smokers. Only 0.2% of never smokers were current e-cigarette users. One out of 20 participants considered e-cigarettes a lot less harmful than smoking. Being current or former smoker were the strongest correlates current e-cigarette use (OR 30.82, 95%CI 10. 21–69.33 and OR 69.33, 95%CI 23.12–207.90 respectively).

Conclusions

E-cigarette use in Greece is largely confined to current or former smokers, while current use and nicotine use by never smokers is extremely rare. The majority of current e-cigarette users were former smokers. Most participants overestimate the harmfulness of e-cigarettes relative to smoking.

Electronic supplementary material

The online version of this article (10.1186/s12954-018-0229-7) contains supplementary material, which is available to authorized users.

Development and validation of analytical methodology for the quantification of aldehydes in e-cigarette aerosols using UHPLC-UV

Aldehydes are produced in e-cigarette aerosols, as a result of the thermal decomposition of vegetable glycerin, propylene glycerol and flavorings in the atomizer. These aldehydes were collected with derivatization into 2,4-dinitrophenylhydrazine using impinger trapping. A new methodology for simultaneous quantitative analysis of aldehydes in base liquids was developed and validated. Chromatographic separation was carried out on a Jupiter Proteo 90A column, with the mobile phase consisting of 0.1% formic acid in water and acetonitrile, at a flow rate of 0.4 mL/min. Linearity was demonstrated over the range of concentrations 0.025-10 μg/mL, with correlation of determination ≥ 0.999. Intra- and inter-day % relative standard deviation and relative error were ≤ 10%. The lower limit of detection and quantification were 0.008 and 0.025 μg/mL, respectively. This method was further used for the quantification of aldehydes emitted by different base liquids. It has been shown that vegetable glycerin produces the highest percentage of aldehydes after thermal decomposition compared to propylene glycerol. We propose that it can be used for future e-liquids emissions studies.

TA-GC cloning: A new simple and versatile technique for the directional cloning of PCR products for recombinant protein expression

During the last few decades, the recombinant protein expression finds more and more applications. The cloning of protein-coding genes into expression vectors is required to be directional for proper expression, and versatile in order to facilitate gene insertion in multiple different vectors for expression tests. In this study, the TA-GC cloning method is proposed, as a new, simple and efficient method for the directional cloning of protein-coding genes in expression vectors. The presented method features several advantages over existing methods, which tend to be relatively more labour intensive, inflexible or expensive. The proposed method relies on the complementarity between single A- and G-overhangs of the protein-coding gene, obtained after a short incubation with T4 DNA polymerase, and T and C overhangs of the novel vector pET-BccI, created after digestion with the restriction endonuclease BccI. The novel protein-expression vector pET-BccI also facilitates the screening of transformed colonies for recombinant transformants. Evaluation experiments of the proposed TA-GC cloning method showed that 81% of the transformed colonies contained recombinant pET-BccI plasmids, and 98% of the recombinant colonies expressed the desired protein. This demonstrates that TA-GC cloning could be a valuable method for cloning protein-coding genes in expression vectors.

Prevalence and correlates of current daily use of electronic cigarettes in the European Union: analysis of the 2014 Eurobarometer survey

The study purpose was to analyze current daily and current daily nicotine-containing electronic cigarette (EC) use in the European Union (EU). Special Eurobarometer 429, a cross-sectional survey performed in a representative sample of 28 member states of the EU in November and December of 2014, was analyzed. The prevalence of current daily and current daily nicotine-containing EC use was 1.08% (95% CI 0.95-1.20%) and 1.00% (95% CI 0.88-1.12%), respectively, and was mainly observed in current and former smokers. Minimal current daily (0.08%, 95% CI 0.03-0.12%) and current daily nicotine-containing EC use (0.04%, 95% CI 0.01-0.08%) was observed among never smokers. Smoking cessation with the help of ECs was reported by 47.12% (95% CI 41.28-52.96%) of current daily and 49.14% (95% CI 43.12-55.17%) of current daily nicotine-containing EC users. Additionally, 33.18% (95% CI 27.67-38.69%) and 31.40% (95% CI 25.80-36.99%) reported reduction in smoking consumption, respectively. The strongest correlates of daily EC use were being current and former smokers. In the EU in late 2014, current daily EC use was predominantly observed in current and former smokers and was associated with high self-reported rates of smoking cessation and reduction. Current daily EC use by never smokers was extremely infrequent.

E-cigarettes emit very high formaldehyde levels only in conditions that are aversive to users: A replication study under verified realistic use conditions

PURPOSE

In 2015, a study identified 5-15-fold higher levels of formaldehyde emissions from an old-generation e-cigarette tested at 5.0 V compared to tobacco cigarettes. We set to replicate this study using the same e-cigarette equipment and e-liquid, while checking for the generation of dry puffs.

DESIGN

Experienced e-cigarette users (n = 26) took 4 s puffs at different voltage settings and were asked to report the generation of dry puffs. Formaldehyde emissions were measured at both realistic and dry puff conditions.

RESULTS

Dry puffs were detected at ≤4.2 V by 88% of participants; thus, 4.0 V was defined as the upper limit of realistic use. Levels ranged from 3.4 (SE = 2.2) μg/10 puffs at 3.3 V to 718.2 (SE = 58.2) μg/10 puffs at 5.0 V. The levels detected at 4.0 V were 19.8 (SE = 5.6) μg/10 puffs. At 4.0 V, the daily exposure to formaldehyde from consuming 3 g of liquid with the device tested would be 32% lower compared to smoking 20 tobacco cigarettes.

CONCLUSIONS

The high levels of formaldehyde emissions that were reported in a previous study were caused by unrealistic use conditions that create the unpleasant taste of dry puffs to e-cigarette users and are thus avoided.

Electronic cigarette use in the European Union: analysis of a representative sample of 27 460 Europeans from 28 countries

AIMS

To assess prevalence of electronic cigarette (e-cigarette) use, reported changes in smoking status due to e-cigarette use and correlates of e-cigarette use in the European Union (EU) member states in 2014.

DESIGN

Cross-sectional survey of EU citizens representative of the population (Special Eurobarometer 429).

SETTING

All 28 Member States of the EU.

PARTICIPANTS

A total of 27 460 EU citizens aged ≥ 15 years (after excluding those who responded 'Do not know' to the questions about smoking status and e-cigarette use).

MEASUREMENTS

Descriptive analysis [%, 95% confidence interval (CI)] of e-cigarette use prevalence (current use, past use and past experimentation) according to smoking status, self-reported changes in smoking status according to patterns of e-cigarette use and logistic regression analysis to examine correlates of e-cigarette use, especially socio-demographic factors and smoking status.

FINDINGS

Ever e-cigarette use was reported by 31.1% (95% CI = 30.0-32.2%) of current smokers, 10.8% (95% CI = 10.0-11.7%) of former smokers and 2.3% (95% CI = 2.1-2.6%) of never smokers. Past experimentation [7.2% (95% CI = 6.9-7.5%)] was more common than current [1.8% (95% CI = 1.6-1.9%)] and past use [2.6% (95% CI = 2.4-2.8%)]. Extrapolated to the whole population, approximately 48.5 million EU citizens were ever e-cigarette users, with 76.8% using nicotine-containing e-cigarettes. An estimated 6.1 and 9.2 million EU citizens had quit and reduced smoking with the help of e-cigarettes, respectively. Initiation with e-cigarettes was reported by 0.8% (95% CI = 0.6-0.9%) of participants who reported ever use of any tobacco-related product. Only 1.3% (95% CI = 1.1-1.5%) of never smokers used nicotine-containing e-cigarettes, with 0.09% (95% CI = 0.04-0.14%) reporting daily nicotine use. Smoking cessation with the help of e-cigarettes was reported by 35.1% (95% CI = 30.7-39.5%) of current e-cigarette users, while a further 32.2% (95% CI = 29.9-36.5%) reported smoking reduction. Being current [odds ratio (OR) = 21.23, 95% CI = 18.32-24.59) or former smokers (OR = 6.49, 95% CI = 5.49-7.67) were the strongest correlates of ever e-cigarette use.

CONCLUSIONS

E-cigarette use in the European Union appears to be largely confined to current or former smokers, while current use and nicotine use by people who have never smoked is rare. More than one-third of current e-cigarette users polled reported smoking cessation and reduction.