Introduction:Tobacco harm reduction aims to provide reduced risk alternatives to adult smokers who would otherwise continue smoking combustible cigarettes (CCs). This randomized, open-label, three-arm, parallel-group, single-center, short-term confinement study aimed to investigate the effects of exposure to selected harmful and potentially harmful constituents (HPHCs) of cigarette smoke in adult smokers who switched to a carbon-heated tobacco product (CHTP) compared with adult smokers who continued to smoke CCs and those who abstained from smoking for 5 days.Methods:Biomarkers of exposure to HPHCs, including nicotine and urinary excretion of mutagenic material, were measured in 24-hour urine and blood samples in 112 male and female Caucasian smokers switching from CCs to the CHTP ad libitum use. Puffing topography was assessed during product use.Results:Switching to the CHTP or smoking abstinence (SA) resulted in marked decreases from baseline to Day 5 in all biomarkers of exposure measured, including carboxyhemoglobin (43% and 55% decrease in the CHTP and SA groups, respectively). The urinary excretion of mutagenic material was also markedly decreased on Day 5 compared with baseline (89% and 87% decrease in the CHTP and SA groups, respectively). No changes in biomarkers of exposure to HPHCs or urinary mutagenic material were observed between baseline and Day 5 in the CC group.Conclusions:Our results provide clear evidence supporting a reduction in the level of exposure to HPHCs of tobacco smoke in smokers who switch to CHTP under controlled conditions, similar to that observed in SA.Implications:The reductions observed in biomarkers of exposure to HPHCs of tobacco smoke in this short-term study could potentially also reduce the incidence of cancer, cardiovascular and respiratory diseases in those smokers who switch to a heated tobacco product.
Introduction:Heating rather than burning tobacco reduces levels of harmful and potentially harmful constituents, and consumer products using this approach aim to reduce exposure to tobacco toxicants. The Tobacco Heating System (THS) version 2.1 has been enhanced from earlier prototypes with an improved heat control and sensorial experience and thereby user acceptance. Exposure measurements are required to determine whether it may be possible to reduce the individual health risk compared to smoking combustible cigarettes (CCs).Methods:This controlled clinical study randomly assigned 40 smokers to either a group continuing to use of their own CC brand (n = 20) or a group switching to THS 2.1 (n = 20) for 5 days. Biomarkers of exposure were measured at baseline and on day 1 through day 5. Product consumption, Human Puffing Topography, the occurrence of adverse events, and an assessment of subjective effects, such as smoking satisfaction and enjoyment of respiratory tract sensations, were also determined.Results:The group of smokers who switched to THS 2.1 adapted their puffing behavior initially through longer puff duration and more puffs. During the duration of the study, total puff volume returned to baseline levels and the mean daily product consumption increased but with similar nicotine exposure compared to baseline CC use. Biomarkers of exposure to tobacco smoke toxicants which inform product risk assessment were significantly reduced with THS use compared to the CC group. THS 2.1 users experienced less reinforcing effects with THS 2.1 than with their own cigarette brand.Conclusions:THS 2.1 is a promising alternative to smoking CCs. Notwithstanding possible use adaption through consumption or puffing behavior, the exposure to harmful smoke constituents was markedly reduced with the new heated tobacco platform.Implications:Exposure markers to harmful and potentially harmful smoke constituents were lowered with the THS 2.1. Heating tobacco instead of burning can offer a potentially lower risk of delivering nicotine compared to CCs.
Population and family studies were undertaken to validate caffeine as a probe drug to establish the genetic status of rapid acetylators and slow acetylators. The acetylator status was established from the urinary metabolic ratio of 5-acetylamino-6-formylamino-3-methyluracil to 1-methylxanthine (AFMU/1X) after oral administration of caffeine. We confirmed a bimodal distribution (chi 2(1) = 229.48; p << 10(-9)) of the AFMU/1X ratio in 245 unrelated subjects. A third distribution did not significantly improve the fit to the data (chi 2(1) = 0.04; p = 0.84). Complex segregation analysis of 76 nuclear families confirmed the monogenic inheritance of N-acetyltransferase, with incomplete dominance of the rapid allele over the slow one. We observed a slight shift between the mean activities of heterozygous and homozygous rapid acetylators (t = 2.89; p < 0.01). However, the 30 obligate heterozygotes belonging to the 76 families were evenly distributed among the rapid acetylators and never located in a hypothetic intermediary group between slow acetylators and rapid acetylators.
We performed a cross-sectional, multicentre study in Japan to detect the differences in biomarkers of exposure and cardiovascular biomarkers between smokers and non-smokers. Several clinically relevant cardiovascular biomarkers differed significantly between smokers and non-smokers, including lipid metabolism (high-density lipoprotein cholesterol concentrations – lower in smokers), inflammation (fibrinogen and white blood cell count – both higher in smokers), oxidative stress (8-epi-prostaglandin F2α – higher in smokers) and platelet activation (11-dehydro-thromboxane B2 – higher in smokers) (p ≤ 0.0001). These results provide further evidence showing that cardiovascular biomarkers can discriminate smokers from non-smokers, and could be used to evaluate the risks associated with tobacco products.
The assessment of paracetamol absorption kinetics is reproducible when the drug is given together with a semi-solid meal in Helicobacter pylori-negative healthy subjects.
Eight patients with psoriasis were given 200 mg caffeine orally with or without 1.2 mg kg−1 of 5-methoxypsoralen. Blood and urine samples were collected over a 2-day period. During 5-methoxypsoralen coadministration, the apparent volume of distribution of caffeine remained unchanged, but oral clearance (CL p.o. ) decreased from 9.5±3.8 (mean±s.d.) to 3.2±0.5 l h−1 (P<0.01). The area under the plasma concentration-time curve (AUC) increased from 24±9 to 73±29 mg l−1 h (P<0.001). This decrease in CL p.o. with increased AUC was consistent with a CYP1A2-dependent inhibition of caffeine N-demethylation which was further supported by significant decreases in the (AFMU+1U+1X)/17U and (AFMU+1U+1X)/17X urinary metabolic ratios.
The potential of a diclofenac-Na EmulgelTM (diclofenac gel) to alleviate the pain and associated symptoms caused by sunburn has been evaluated versus vehicle. Sunburn was induced on the buttock skin of healthy adult male subjects by irradiation with UVA + UVB rays. Investigational products were applied 6 and 10 h after irradiation, and efficacy was assessed on the basis of spontaneous and provoked pain, erythema, oedema, skin colour and temperature. The minimal efficacious concentration evaluated in an extension (0.1 vs. 0.25% diclofenac gel) of a previous concentration-finding study (1, 0.5 and 0.25% diclofenac gel) was 0.1% and was efficacious in alleviating pain (spontaneous and provoked) as well as reducing erythema, oedema and skin temperature. In a single- versus 2-application comparison study, a single application of 0.1% gel was sufficient to alleviate the pain and accompanying symptoms of sunburn with an onset of action 2 h after application. A second application of gel 4 h after the first maintained the analgesia and reduction of other symptoms for a period of up to 48 h after irradiation.
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