Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nicotine Tob Res ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38035623

RESUMO

INTRODUCTION: IQOS HEETS are promoted as reduced risk alternatives to cigarettes. Although some studies have investigated the chemical composition of HEETS emissions, little is known on whether toxicant levels in such emissions are affected by different puffing parameters and flavor varieties. This has important implications when assessing actual human exposure, since IQOS users develop a specific and personalized puffing behavior and may use different HEETS variants. METHODS: This study measured the levels of nicotine, Total Particulate Matter (TPM), carbonyl compounds and tobacco-Specific Nitrosamines (TSNAs) in the emissions of nine differently flavored HEETS and two cigarettes (1R6F and Marlboro Red, MR). Emissions from Yellow HEETS, 1R6F and MR were collected using the World Health Organization Intense (WHOI) smoking regime and four more intense smoking regimes. RESULTS: Yellow HEETS aerosol contained lower levels of toxicants compared to 1R6F and MR smoke. More intense smoking regimes increased carbonyls release in cigarette smoke, whereas only higher puff frequency led to lower levels of toxicants in Yellow HEETS aerosol. Some HEETS varieties exhibited higher levels of formaldehyde and TSNAs in their aerosol compared to Yellow HEETS. CONCLUSIONS: Puff frequency was identified as the only smoking parameter that significantly lowered the release of almost all toxicants in Yellow HEETS, whereas a combination of higher puff volume and puff duration led to increased levels of some carbonyls. Differences in toxicants levels between various commercially-available HEETS have important implications when assessing their health impact, as their consumption might induce different toxicant exposure and health effects. IMPLICATIONS: HEETS release about half as much nicotine and substantially lower levels of toxicants compared to cigarettes. Literature data showed that puffing intensity is increased in cigarette smokers switching to HEETS, maybe in reaction to these lower nicotine levels. Our results show a differential impact of increased puff frequency, puff duration and puff volume in the release of toxicants from HEETS. Thus, industry-independent studies on puff topography are critical to make choices for the most relevant puffing regime for HTP regulation. Regulators should consider evaluating the health impact of multiple HEETS varieties, as the tobacco filler composition significantly affects the release of certain toxicants.

2.
Health Educ Res ; 38(2): 150-162, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36727168

RESUMO

The effectiveness of e-cigarettes in smoking cessation is under debate. Informing smokers who are motivated to quit smoking about e-cigarettes may help them to make an informed decision about their use for smoking cessation, which, however, may also lead to unintended effects such as less quitting. This experimental study assessed the influence of providing tailored information about e-cigarettes in a web-based tailored smoking cessation intervention on participants' decision-making and smoking behavior. Adult smokers (N = 331) were randomized into a personalized eHealth intervention on (i) smoking cessation (control condition) or (ii) smoking cessation and information about e-cigarettes (intervention condition). Directly postintervention, participants in the intervention condition had more knowledge about e-cigarettes than participants in the control condition. Attitudes toward e-cigarettes were more positive among intervention participants than control participants, but the differences in attitude were less pronounced than the differences in knowledge and not consistent across items. At a 6-month follow-up, no between-condition differences were observed in the use of e-cigarettes as a smoking cessation method, the number of tobacco cigarettes smoked in the past 7 days, or other smoking outcomes.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Adulto , Humanos , Abandono do Hábito de Fumar/métodos , Fumar , Fumar Tabaco , Fumantes
3.
Ned Tijdschr Geneeskd ; 160: D833, 2017.
Artigo em Holandês | MEDLINE | ID: mdl-28181894

RESUMO

- Two recent societal cost-benefit analyses have documented the costs of smoking and the cost-effectiveness of preventing smoking.- Smoking costs the Netherlands society EUR 33 billion per year.- The majority of this is the monetary value of health loss; these are "soft" euros that cannot be re-spent.- There is not a great deal of difference between costs and benefits when expressed in "hard" euros, which means that there is no clear business case for anti-smoking policy.- The greatest benefit of discouraging smoking is improved health for the individual and increased productivity for the business sector; however, the benefits cannot be easily realised, because even in the most favourable scenario the number of smokers will decrease slowly.- Excise duties seem to offer the most promising avenue for combating smoking. The benefits of anti-smoking policy, therefore, consist mainly of tax revenues for the government.- Stringent policy is required to transform tax revenues into health gains.


Assuntos
Prevenção do Hábito de Fumar/economia , Fumar/economia , Comércio , Análise Custo-Benefício , Custos de Cuidados de Saúde , Humanos , Países Baixos , Impostos
4.
Eur J Biochem ; 268(6): 1554-60, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11248672

RESUMO

Understanding the structural basis of inhibitor-enzyme interactions, important for the design of new drugs, requires a complete thermodynamic characterization of the binding process as well as a description of the structure of the complex. In this paper, the binding of p-substituted benzamidinium derivatives to the structurally well-characterized serine proteinase bovine pancreatic trypsin has been studied using isothermal titration calorimetry. These experiments have permitted a complete characterization of the temperature dependence of the inhibitor-binding thermodynamics. At 25 degrees C, both the enthalpy and entropy of binding are favourable for all studied derivatives, but this is only true for a relatively narrow temperature range. As binding is characterized by a negative change in heat capacity, the process is characterized by enthalpy--entropy compensation, resulting in a change of the net thermodynamic driving force for association from entropic to enthalpic with increasing temperature. These phenomena are not unusual when hydrophobic forces play an important role. The trend in the relative binding potencies can, to a significant extent, be attributed to the electron-donating/withdrawing character of the substituent at the para position, as shown by the Hammett sigma(p)(+) plot for the different inhibitors; the more polar the p-substituted benzamidine, the less potent it will be as a trypsin inhibitor. This behaviour might result from a bulk solvation effect, meaning that the more polar, lower potency inhibitors will be more stabilized in water than the less polar, higher potency inhibitors.


Assuntos
Benzamidinas/metabolismo , Tripsina/metabolismo , Benzamidinas/química , Calorimetria , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Termodinâmica , Tripsina/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...