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1.
Nicotine Tob Res ; 22(4): 549-559, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-31125079

RESUMO

INTRODUCTION: Tobacco Heating System (THS) 2.2, a candidate modified-risk tobacco product, aims at offering an alternative to cigarettes for smokers while substantially reducing the exposure to harmful and potentially harmful constituents found in cigarette smoke. METHODS: One hundred and sixty healthy adult US smokers participated in this randomized, three-arm parallel group, controlled clinical study. Subjects were randomized in a 2:1:1 ratio to menthol Tobacco Heating System 2.2 (mTHS), menthol cigarette, or smoking abstinence for 5 days in confinement and 86 subsequent ambulatory days. Endpoints included biomarkers of exposure to harmful and potentially harmful constituents (reported in our co-publication, Part 1) and biomarkers of potential harm (BOPH). RESULTS: Compliance (protocol and allocated product exposure) was 51% and 18% in the mTHS and smoking abstinence arms, respectively, on day 90. Nonetheless, favorable changes in BOPHs of lipid metabolism (total cholesterol and high- and low-density cholesterol), endothelial dysfunction (soluble intercellular adhesion molecule-1), oxidative stress (8-epi-prostaglandin F2α), and cardiovascular risk factors (eg, high-sensitivity C-reactive protein) were observed in the mTHS group. Favorable effects in other BOPHs, including ones related to platelet activation (11-dehydrothromboxane B2) and metabolic syndrome (glucose), were more pronounced in normal weight subjects. CONCLUSIONS: The results suggest that the reduced exposure demonstrated when switching to mTHS is associated with overall improvements in BOPHs, which are indicative of pathomechanistic pathways underlying the development of smoking-related diseases, with some stronger effects in normal weight subjects. IMPLICATIONS: Switching to mTHS was associated with favorable changes for some BOPHs indicative of biological pathway alterations (eg, oxidative stress and endothelial dysfunction). The results suggest that switching to mTHS has the potential to reduce the adverse health effects of smoking and ultimately the risk of smoking-related diseases. Switching to mTHS for 90 days led to reductions in a number of biomarkers of exposure in smokers, relative to those who continued smoking cigarettes, which were close to those observed when stopping smoking (reported in our co-publication, Part 1). Initial findings suggest reduced levels of 8-epi-prostaglandin F2α and intercellular adhesion molecule 1, when switching to mTHS for 90 days. These changes are comparable to what is observed upon smoking cessation. In normal weight subjects, additional favorable changes were seen in 11-dehydrothromboxane B2, fibrinogen, homocysteine, hs-CRP, percentage of predicted forced expiratory volume in 1 second, systolic blood pressure, diastolic blood pressure, glucose, high-density lipoprotein, apolipoprotein A1, and triglycerides. TRIAL REGISTRATION: NCT01989156.


Assuntos
Biomarcadores/sangue , Sistemas Eletrônicos de Liberação de Nicotina/normas , Redução do Dano , Calefação/métodos , Mentol/administração & dosagem , Fumaça/análise , Fumar/efeitos adversos , Adulto , Idoso , Antipruriginosos/administração & dosagem , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Feminino , Comportamentos Relacionados com a Saúde , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Fumantes/psicologia , Fumantes/estatística & dados numéricos , Fumar/psicologia , Adulto Jovem
2.
Nicotine Tob Res ; 22(4): 539-548, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30722062

RESUMO

INTRODUCTION: The Tobacco Heating System (THS) is a "heat-not-burn" tobacco product designed to generate significantly lower levels of harmful and potentially harmful constituents (HPHCs) and present lower risk of harm than cigarettes. This study assessed the exposure reduction to selected HPHCs in smokers switching to menthol Tobacco Heating System (mTHS) 2.2 compared with smokers continuing smoking menthol cigarettes (mCCs) and smoking abstinence (SA) for 5 days in a confined setting, followed by an 86-day ambulatory period. METHODS: A total of 160 healthy adult US smokers participated in this randomized, three-arm parallel group, controlled clinical study. Biomarkers of exposure to 16 HPHCs were measured in blood and 24-hour urine. Safety was monitored throughout the study. Information was also gathered on product evaluation, product use, subjective effects, and clinical risk markers (co-publication Part 2). RESULTS: Nicotine uptake was comparable in both exposure groups (mTHS:mCC ratio of 96% on day 90). On day 5, biomarker of exposure levels to other HPHCs were reduced by 51%-96% in the mTHS group compared with the mCC group, and these reductions were sustained for most biomarkers of exposure over ambulatory period. After 90 days of use, the level of satisfaction with mTHS and suppression of urge to smoke were comparable to mCC. CONCLUSION: Switching from mCCs to mTHS significantly reduced the exposure to HPHCs to levels approaching those observed in subjects who abstained from smoking for the duration of the study. IMPLICATIONS: This study compared the impact of switching to mTHS on biomarkers of exposure, relative to continued smoking or SA. TRIAL REGISTRATION: NCT01989156 (ClinicalTrials.gov).


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina/normas , Redução do Dano , Calefação/métodos , Mentol/administração & dosagem , Fumaça/análise , Fumantes/psicologia , Fumar/efeitos adversos , Adulto , Idoso , Antipruriginosos/administração & dosagem , Biomarcadores/sangue , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Feminino , Comportamentos Relacionados com a Saúde , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco/métodos , Fumar/psicologia , Adulto Jovem
3.
Regul Toxicol Pharmacol ; 81: 489-499, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27693654

RESUMO

Smoking conventional cigarettes (CCs) exposes smokers to harmful and potentially harmful constituents (HPHCs). The Tobacco Heating System 2.2 (THS 2.2), a candidate modified risk tobacco product, was developed to reduce or eliminate the formation of HPHCs, while preserving as much as possible the taste, sensory experience, nicotine delivery profile and ritual characteristics of CC. This randomized, controlled, open-label study in confinement for 5 day exposure aimed to demonstrate the reduction in exposure to selected HPHCs, to assess nicotine uptake and subjective effects, in participants switching to THS 2.2 (n = 80) compared to participants continuing smoking CCs (n = 40) and abstaining from smoking (n = 40). The subjects were randomized according to sex and daily CC consumption. The levels of biomarkers of exposure to HPHCs were significantly reduced in participants switching to THS 2.2, compared to CC use. More importantly, the magnitude of exposure reduction observed was close to that which was seen in participants who abstained from smoking for 5 days, while nicotine uptake was maintained. Reduction in urge-to-smoke was comparable between THS and CC groups, however THS 2.2 was slightly less satisfactory than CCs. The new, alternative tobacco product THS 2.2 was well tolerated.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina/instrumentação , Calefação , Nicotiana/efeitos adversos , Fumar/efeitos adversos , Produtos do Tabaco/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Cancer Epidemiol Biomarkers Prev ; 28(11): 1934-1943, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31270101

RESUMO

BACKGROUND: Cigarette smoking increases the risk of chronic diseases; heating instead of burning tobacco can lower these risks, contributing to tobacco harm reduction. This study (with 984 adult American smokers) examined whether favorable changes occur in 8 co-primary endpoints (HDL-C, WBC, FEV1%pred, COHb, Total NNAL, sICAM-1, 11-DTX-B2, 8-epi-PGF2α) indicative of biological and functional effects when cigarette smokers switch to the heat-not-burn Tobacco Heating System 2.2 (THS). Additionally, these biomarkers of exposure (BoExp) were quantified: MHBMA, 3-HPMA, Total NNN, CEMA, 3-OH-B[a]P, HMPMA, Total 1-OHP, NEQ, and CO exhaled. METHODS: Participants were randomized to continued smoking of their preferred cigarette brand (n = 496) or to using THS (IQOS brand; n = 488) for 6 months. THS has a maximum heating temperature of 350°C, delivering 1.21 mg nicotine/stick and 3.94 mg glycerin/stick under the Health Canada Intense smoking regimen. RESULTS: The main outcome was a favorable change 6 months after baseline, with statistically significant improvements in 5 of 8 biomarkers of effect (HDL-C, WBC, FEV1%pred, COHb, Total NNAL) when smokers switched to THS compared with those who continued to smoke cigarettes. Likewise, BoExp were markedly reduced. CONCLUSIONS: All endpoints showed favorable changes in the same direction as with smoking cessation and improved biological effects were observed in smokers who predominantly used THS compared with continued cigarette smoking, with similar nicotine levels in both groups. IMPACT: Improvements in 5 of 8 biomarkers of effect are supportive of the research hypothesis, suggestive of disease risk reduction potential for smokers switching to THS instead of continuing to smoke cigarettes.


Assuntos
Biomarcadores/química , Feminino , Humanos , Masculino , Produtos do Tabaco/efeitos adversos , Produtos do Tabaco/análise
5.
JMIR Res Protoc ; 7(8): e11294, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30143474

RESUMO

BACKGROUND: Tobacco harm reduction, substituting less harmful tobacco products for combustible cigarettes, is a complementary approach for smokers who would otherwise continue to smoke. The Philip Morris International (PMI) Tobacco Heating System (THS) 2.2 is a novel tobacco product with the potential to reduce the risk of harm in smokers compared to continued smoking of combustible cigarettes. It heats tobacco electrically in a controlled manner, never allowing the temperature to exceed 350°C, thereby preventing the combustion process from taking place and producing substantially lower levels of toxicants while providing nicotine, taste, ritual, and a sensory experience that closely parallels combustible cigarettes. Previous clinical studies have demonstrated reduced exposure to the toxicants (approaching the levels observed after quitting) for smokers who switched to THS 2.2, for three months. For adult smokers who would otherwise continue smoking combustible cigarettes, switching to THS 2.2 may represent an alternative way to reduce the risk of tobacco-related diseases. OBJECTIVE: This study aimed to further substantiate the harm reduction potential of THS 2.2 by demonstrating favorable changes in a set of 8 coprimary endpoints, representative of pathomechanistic pathways (ie, inflammation, oxidative stress, lipid metabolism, respiratory function, and genotoxicity), linked to smoking-related diseases, in smokers switching from combustible cigarettes to THS 2.2. METHODS: This study was a randomized, controlled, two-arm parallel group, multicenter ambulatory US study conducted in healthy adult smokers switching from combustible cigarettes to THS 2.2 compared with smokers continuing to smoke combustible cigarettes for six months. Subjects had a smoking history of at least ten years and did not intend to quit within the next six months. RESULTS: Enrollment started in March 2015 and the trial was completed in September 2016. In total, 984 subjects were randomized (combustible cigarettes, n=483; THS 2.2, n=477), and 803 completed the study. The results are expected to be available in a subsequent publication in 2019. CONCLUSIONS: In this paper, we describe the rationale and design for this clinical study that focused on the evaluation of THS 2.2's potential to reduce the risk of smoking-related diseases compared with that of combustible cigarettes. This study will provide insights regarding favorable changes in biological and functional endpoints informed by effects known to be seen upon smoking cessation. TRIAL REGISTRATION: ClinicalTrials.gov NCT02396381; http://clinicaltrials.gov/ct2/show/NCT02396381 (Archived by WebCite at http://www.webcitation.org/71PCRdagP). REGISTERED REPORT IDENTIFIER: RR1-10.2196/11294.

6.
J Thorac Cardiovasc Surg ; 129(1): 138-45, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15632835

RESUMO

OBJECTIVE: Surgical left ventricular restoration by means of endoventricular patch aneurysmectomy in patients with postinfarction aneurysm should result in acute improved left ventricular performance by decreasing mechanical dyssynchrony and increasing energy efficiency. METHODS: Nine patients with left ventricular postinfarction aneurysm were studied intraoperatively before and after ventricular restoration with a conductance volume catheter to analyze pressure-volume relationships, energy efficiency, and mechanical dyssynchrony. The end-systolic elastance was used as a load-independent index of contractile state. Left ventricular energy efficiency was calculated from stroke work and total pressure-volume area. Segmental volume changes perpendicular to the long axis were used to calculate mechanical dyssynchrony. Statistical analysis was performed with the paired t test and least-squares linear regression. RESULTS: Endoventricular patch aneurysmectomy reduced end-diastolic volume by 37% (P < .001), with unchanged stroke volume. Systolic function improved, as derived from increased +dP/dt(max), by 42% (P < .03), peak ejection rate by 28% (P < .02), and ejection fraction by 16% (P < .0002). Early diastolic function improved, as shown by reduction of -dP/dt(max) by 34% (P < .006) and shortened tau by 30% (P < .001). Left ventricular end-systolic elastance increased from 1.2 +/- 0.6 to 2.2 +/- 1 mm Hg/mL (P < .001). Left ventricular energy efficiency increased by 36% (P < .002). Left ventricular mechanical dyssynchrony decreased during systole by 33% (P < .001) and during diastole by 20% (P < .005). CONCLUSIONS: Left ventricular restoration induced acute improvements in contractile state, energy efficiency, and relaxation, together with a decrease in left ventricular mechanical dyssynchrony.


Assuntos
Aneurisma Cardíaco/cirurgia , Contração Miocárdica/fisiologia , Infarto do Miocárdio/complicações , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Feminino , Seguimentos , Aneurisma Cardíaco/etiologia , Testes de Função Cardíaca , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Probabilidade , Estudos Prospectivos , Estudos de Amostragem , Resultado do Tratamento , Remodelação Ventricular/fisiologia
7.
Chir Ital ; 57(2): 153-8, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-15916140

RESUMO

The evaluation of any functional disease affecting quality of life requires a purpose-designed quality-of-life index for clinical trials as well as for evaluating the outcomes of treatments. The fecal incontinence quality of life index (FIQL) was developed at Minnesota University (USA) for patients with faecal incontinence but could not be used for Italian patients without appropriate cultural and linguistic adaptation. Therefore this index was translated into italian and prospectively validated on a new series of 73 incontinent patients and 8 healthy controls in order to provide Italian coloproctologists with a useful tool for clinical research. The italian version or the FIQL index met all the statistical criteria of reliability, reproducibility, specificity and convergency required and therefore can be used with confidence in clinical trials on such patients.


Assuntos
Incontinência Fecal , Qualidade de Vida , Inquéritos e Questionários , Adulto , Idoso , Incontinência Fecal/diagnóstico , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
8.
Ann Thorac Surg ; 79(3): 872-80, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15734398

RESUMO

BACKGROUND: Intraaortic balloon counterpulsation (IABP) timing errors during arrhythmia may result in afterload increases which may negatively influence left ventricular (LV) ejection and LV mechanical dyssynchrony. The aim of our study was to determine beat-to-beat effects of properly timed IABP, premature IAB inflation, and late IAB deflation on LV performance and LV mechanical dyssynchrony in heart failure patients undergoing cardiac surgery. METHODS: In 15 patients, LV pressure-volume relations and LV dyssynchrony were measured by conductance volume catheter. Properly timed IABP was evaluated at a 1:1 assist ratio within a 10 seconds time-span. Premature IAB inflation and late IAB deflation were evaluated at a 1:4 assist ratio. RESULTS: Properly timed 1:1 IABP acutely decreased LV end-systolic volume by 6.1% (p < 0.0001) and LV end-systolic pressure by 17.5% (p < 0.0001) due to decreased aortic impedance. Stroke volume (SV) increased by 14% (p < 0.0001), which correlated markedly with a decrease of LV mechanical dyssynchrony (p < 0.0001). The largest SV increases occurred in patients with lowest contractile state. Premature IAB inflation decreased SV by 20% (p < 0.0001) due to abrupt increase of LV afterload during late ejection. Late IAB deflation increased SV and stroke work by 18% (p < 0.0001) and 16% (p < 0.01) respectively, due to increased afterload during early ejection and decreased afterload during late ejection. CONCLUSIONS: Left ventricular performance during IABP is causally related to changes in LV afterload, and the timing of these changes in relation to contraction or relaxation phases, to LV mechanical dyssynchrony and to contractile state.


Assuntos
Balão Intra-Aórtico , Volume Sistólico , Função Ventricular Esquerda , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
9.
Ann Thorac Surg ; 79(3): 1017-22; discussion 1022, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15734425

RESUMO

PURPOSE: The efficacy of intraaortic balloon counterpulsation (IABP) during arrhythmic episodes is questionable. A novel algorithm for intrabeat prediction of the dicrotic notch was used for real time IABP inflation timing control. DESCRIPTION: A windkessel model algorithm was used to calculate real-time aortic flow from aortic pressure. The dicrotic notch was predicted using a percentage of calculated peak flow. Automatic inflation timing was set at intrabeat predicted dicrotic notch and was combined with automatic IAB deflation. EVALUATION: Prophylactic IABP was applied in 27 patients with low ejection fraction (< 35%) undergoing cardiac surgery. Analysis of IABP at a 1:4 ratio revealed that IAB inflation occurred at a mean of 0.6 +/- 5 ms from the dicrotic notch. In all patients accurate automatic timing at a 1:1 assist ratio was performed. Seventeen patients had episodes of severe arrhythmia, the novel IABP inflation algorithm accurately assisted 318 of 320 arrhythmic beats at a 1:1 ratio. CONCLUSIONS: The novel real-time intrabeat IABP inflation timing algorithm performed accurately in all patients during both regular rhythms and severe arrhythmia, allowing fully automatic intrabeat IABP timing.


Assuntos
Algoritmos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Balão Intra-Aórtico/métodos , Idoso , Pressão Sanguínea , Procedimentos Cirúrgicos Cardíacos , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
10.
J Clin Monit Comput ; 17(3-4): 181-5, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12455734

RESUMO

A novel algorithm for real-time detection and prediction of the dicrotic notch from aortic pressure waves was evaluated in arrhythmic aortic pressure signals from heart failure patients. A simplified model of the arterial tree was used to calculate real-time aortic flow from aortic pressure. The dicrotic notch was detected at the first negative dip from the calculated flow, prediction of the notch was performed using a percentage of the decreasing flow. The performance of the real-time dicrotic notch detection algorithm (RTDND) was evaluated during severe arrhythmia from aortic pressure signals of 12 patients. The RTDND was able to detect the dicrotic notch in 98.1%. No false positive dicrotic notch identifications were observed. Prediction of the dicrotic notch was tested at 40%, 20%, and 0% of the decreasing calculated aortic flow. The mean time-delays to the notch were 68 +/- 14 ms, 55 +/- 12 ms, and 43 +/- 8 ms, respectively. Given these small variability, intra-beat prediction of the dicrotic notch may be used for real-time intra-aortic balloon counterpulsation inflation timing.


Assuntos
Algoritmos , Arritmias Cardíacas/fisiopatologia , Pressão Sanguínea , Idoso , Aorta Torácica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador
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