Plasma Nicotine Research Articles

Application of the response surface methodology in the optimization of modified molecularly imprinted polymer based pipette-tip micro-solid phase extraction for spectrophotometric determination of nicotine in seawater and human plasma

In this paper, a novel molecularly imprinted polymer/zinc oxide (MIP/ZnO) was synthesized and applied as an adsorbent for pipette-tip micro-solid phase extraction (MIP/ZnO PT-μSPE) of nicotine from seawater and human plasma followed by its spectrophotometric detection.

A Case Report of Cardiac Arrest Following Intentional Ingestion of Liquid Nicotine for Electronic Cigarette

Acute nicotine poisoning by liquid nicotine for electronic cigarettes is becoming an increasing problem worldwide. On the other hand, there are no regulations regarding its concentration, container or labelling in Korea. This is the first case of a cardiac arrest after liquid nicotine ingestion that was confirmed by plasma nicotine detection in Korea. A 34-year-old male was found with a cardiac arrest at home by the emergency medical services crew, and had a return of spontaneous circulation after 27 minutes of cardio-pulmonary resuscitation. The cause of his cardiac arrest was suspected to be acute nicotine poisoning by the ingestion of liquid nicotine. Toxicology analysis of the National Forensic Service confirmed plasma nicotine, and the pharmacokinetic estimated average concentration of plasma nicotine at the time of the cardiac arrest was 29.7 mg/L, a lethal dose. He was hospitalized for further treatment, but was discharged after 20 days without any improvement. Considering the strong toxicity of nicotine, appropriate policy decisions are required for sales and distribution.

Effects of Nicotine Metabolic Rate on Withdrawal Symptoms and Response to Cigarette Smoking After Abstinence.

This study investigated the influence of the rate of nicotine metabolism, as indicated by the nicotine metabolite ratio (NMR), on tobacco dependence. We stratified 136 smokers on the basis of saliva NMR as fast (n=65) and slow (n=71) metabolizers. Two "loading cigarettes" were smoked after overnight, and a "reward cigarette" was smoked after 6hours of daytime, abstinence. Blood nicotine concentrations, expired carbon monoxide, withdrawal/craving, and reward questionnaires were collected before/after smoking and during daytime abstinence. Compared with slow metabolizers, fast metabolizers had a shorter nicotine elimination half-life (P<0.001), lower plasma nicotine concentrations (P<0.001), and higher withdrawal/craving scores (P<0.05) for most times during daytime abstinence, indicating that fast metabolizers are likely smoking more to relieve withdrawal symptoms (negative reinforcement). Reward/satisfaction scores were similar in fast and slow metabolizers, suggesting that faster nicotine metabolism, assessed by NMR, is not associated with greater positive reinforcement. CYP2A6 normal (n=82) and reduced (n=42) genotype predicted plasma nicotine concentrations but not withdrawal symptoms.

Biomarkers of Exposure Specific to E-vapor Products Based on Stable-Isotope Labeled Ingredients.

An important basis for risk estimation for e-cigarette (e-cig) users is a well-founded dosimetry. The objective of this study was to assess the applicability of stable-isotope e-liquid ingredients for exposure studies in vapers. E-cigs with 10% of labeled propylene glycol (PG), glycerol (G), and nicotine was used by 20 experienced vapers under controlled (Part A) and free (Part B) conditions. In Part A, 10 subjects vaped at 10 W and another 10 subjects at 18 W power setting of the e-cig. In Part B, the same subjects used the same product ad libitum in their usual environment. Five smokers, smoking 10 non-filter cigarettes, spiked with labeled PG, G, and nicotine, served as positive control during Part A. PG, G, nicotine and its metabolites were measured in plasma, urine, and saliva. Peak nicotine levels (sum of measured labeled and unlabeled) in plasma were lower in vapers (15.8 to 19.6 ng/mL) than in smokers (36 ng/mL). The labeled plasma nicotine levels were ten times lower than the unlabeled, reflecting the ratio in the e-liquid. PG levels in plasma and urine also reflected the vaping activities in Part A, while G in these body fluids showed no association with vaping. This proof of concept study shows that the application of labeled e-liquid ingredients allows the accurate quantification of the dose of nicotine and PG when other nicotine and tobacco products were used simultaneously. Unchanged G was not assessable by this approach. This approach allows the investigations of the absorption of potential PG-, G-, and nicotine-derived vapor constituents (eg, aldehydes and epoxides) by vaping. Appropriate studies are in progress in our laboratory.

Effects of Menthol Flavor Cigarettes or Total Urinary Menthol on Biomarkers of Nicotine and Carcinogenic Exposure and Behavioral Measures.

The effects of either menthol flavor cigarettes or total urinary menthol on nicotine dependence, biomarkers of addictive and carcinogenic exposure, and behavioral measures may inform differences and similarities of these two approaches. Stratified recruitment by cigarette (menthol flavor or regular) and race (African American and white) yielded a balanced sample of 136 adult smokers in a 36-hour inpatient protocol. Exposure measures assessed during 24-hour data collection included urinary menthol, total NNAL [4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol], 10 polycyclic aromatic hydrocarbon metabolites, baseline plasma cotinine, plasma nicotine pre- and post-smoking, exhaled carbon monoxide pre- and post-smoking, and cigarette puff volumes. The latter three were measured at four specified timepoints throughout the day. There were no significant differences between menthol flavor and regular cigarette smokers in measures of nicotine dependence, biomarkers of addictive and carcinogenic exposures, or behavioral measures. Significant race × cigarette type interaction effects were found for two biomarkers: plasma nicotine and 3-hydroxyphenanthrene. Total urinary menthol was significantly associated with higher levels of nearly all dependent variables including puff volume, exhaled carbon monoxide, plasma nicotine and cotinine, NNAL, and polycyclic aromatic hydrocarbons. The significant effects of total urinary menthol were sustained after adjusting for menthol flavor and regular cigarette type and other covariates (eg, number of cigarettes per day, baseline cotinine, and baseline nicotine). Urinary menthol is an independent predictive biomarker for nicotine dependence, addictive and carcinogenic exposure, and behaviors. Comparison of the effects of menthol flavor and total urinary menthol on nicotine dependence, biomarkers of addictive and carcinogenic exposure, and behavioral measures emphasizes the important significant contribution of total urinary menthol concentrations in contrast to no significant associations by dichotomous cigarette type with these biomarkers.

Acute Effect of Hookah Smoking on Arterial Stiffness and Wave Reflections in Adults Aged 18 to 34 Years of Age

Hookah (waterpipe) smoking is rapidly increasing in popularity worldwide. Despite being heavily advertised in the media as a healthier alternative to cigarettes, the toxicology of hookah smoke suggest otherwise. Cigarette smoking unequivocally causes an acute increase in arterial stiffness, but whether hookah does the same is unknown. In 48 young healthy habitual hookah but not cigarette smokers, we measured heart rate, peripheral and central blood pressure, carotid-femoral pulse wave velocity (measure of arterial stiffness), aortic augmentation index (measure of wave reflection), plasma nicotine, and exhaled carbon monoxide before and after ad lib hookah smoking. Hookah smoking increased heart rate by +16 ± 1 beats/min and mean brachial arterial pressure by +6 ± 1 mm Hg (both p <0.05, mean ± SE). Most importantly, it increased carotid-femoral pulse wave velocity and aortic augmentation index by +0.66 ± 0.09 m/s-1 and +8.76 ± 3.99%, respectively (p <0.05, mean ± SE), denoting increased acute arterial stiffness. These vascular effects were accompanied by increases in plasma nicotine concentration (+5.8 ± 1.2 ng/ml, p <0.05) and expired carbon monoxide (+25.44 ± 1.68 ppm, p <0.05). All these parameters were unchanged during time-control studies (n = 14). Thus, in contrast to effective media marketing of hookah as a safer alternative to cigarettes, the present study shows for the first time that in young adult hookah smokers, a single hookah smoking session causes an acute increase in arterial stiffness of comparable magnitude to what has been previously reported for cigarettes. Further research is warranted to determine whether habitual hookah smoking accelerates the age-dependent development of hypertension and its cardiovascular complications.

Comparison of the Conventional and Electroenhanced Direct-Immersion Solid-Phase Microextraction for Sampling of Nicotine in Biological Fluids of the Human Body.

A stainless steel fiber was made porous and adhesive by platinization and then coated by nanostructured polypyrrole (PPy), using an appropriate electrophoretic deposition (EPD) method. The morphological surface structure and functional groups of the PPy-coated fiber were studied using SEM (Scanning electron microscope) instrument. The prepared fiber was used for comparison of direct immersion (DI) and electroenhanced direct immersion solid-phase microextraction (EE-DI-SPME) of nicotine in human plasma and urine samples followed by gas chromatography flame ionization detector (GC-FID) determination. The effects of the influential experimental parameters on the efficiency of the DI-SPME and EE-DI-SPME methods, including the pH and ionic strength of the sample solution, applied Direct current (DC) voltage, extraction temperature and time and stirring rate, were optimized. Under the optimal conditions, the calibration curves for the DI-SPME-GC-FID and EE-DI-SPME-GC-FID methods were linear over the ranges of 0.1–10.0 μg mL−1 and 0.001–10.0 μg mL−1, respectively. The relative standard deviations (RSDs, n = 6) were found to be 6.1% and 4.6% for the DI and EE strategies, respectively. The LODs (limit of detection) of the DI-SPME-GC-FID and EE-DI-SPME-GC-FID methods were found to be 10 and 0.3 ng mL−1, respectively. The relative recovery values (for the analysis of 1 µg mL−1 nicotine) were found to be 91–110% for EE-DI-SPME and 75–105% for DI-SPME. The enrichment factors for DI-SPME and EE-DI-SPME sampling were obtained as 38,734 and 50,597, respectively. The results indicated that EE-SPME was more efficient for quantitation of nicotine in biological fluids. The developed procedure was successfully carried out for the extraction and measurement of nicotine in real plasma and urine samples.

Hookah Smoking Causes an Acute Adverse Effect on Arterial Stiffness and Wave Reflections in Young Adults

Hookah (waterpipe) smoking is a centuries‐old, revived yet understudied epidemic of tobacco use. Despite being heavily advertised and glamorized in the media as a healthier alternative to cigarettes, the toxicology of hookah smoke suggest otherwise. Cigarette smoking unequivocally causes an acute increase in arterial stiffness, but whether hookah does the same is unknown. In 48 young healthy habitual hookah but not cigarette smokers, we measured heart rate, peripheral and central blood pressure, carotid‐femoral pulse wave velocity (measure of arterial stiffness), aortic augmentation index (measure of wave reflection), plasma nicotine, and exhaled carbon monoxide (CO) before and after 30 minutes of ad lib hookah smoking. Hookah smoking increased heart rate by +16 ± 1 beats/min and mean brachial arterial pressure by +6 ± 1 mmHg (both p &lt; 0.05, mean ± SE). Most importantly, it increased carotid‐femoral pulse wave velocity and aortic augmentation index by +0.66 ± 0.09 m/s−1and +8.76 ± 3.99%, respectively (p &lt;0.05, mean ± SE), denoting increased acute arterial stiffness. These vascular effects were accompanied by increases in plasma nicotine concentration (+5.8 ± 1.2 ng/ml, p&lt;0.05) and expired CO (+25.44 ± 1.68 ppm, p&lt; 0.05). All these parameters were unchanged during time‐control studies (n=14). Thus, in contrast to effective media marketing of hookah as a safer alternative to cigarettes, the present study shows for the first time that in young adult hookah smokers, a single hookah smoking session causes an acute increase in arterial stiffness of comparable magnitude to what has been previously reported for cigarettes. Further research is warranted to determine whether habitual hookah smoking accelerates the age‐dependent development of hypertension and its cardiovascular complications.Support or Funding InformationThis study was funded by the Tobacco‐Related Disease Research Program to Dr. Mary Rezk‐ Hanna (#23DT‐0102) and Dr. Ronald Victor (#22XT‐0017).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Tobacco Smoking and Brain Endogenous Opioid Release: More Than Nicotine Alone.

The effects of smoking denicotinized (denic) and average nicotine (avnic) tobacco cigarettes were studied on brain mu opioid receptor binding by positron emission tomography with 11C carfentanil. The results indicated the importance of physiological and psychological effects induced by denic smoking. Regional mu opioid binding potential (nondisplaceable binding potential, BPND) was measured in 20 adult male overnight abstinent chronic tobacco smokers. The denic sessions were conducted about 8:00 am followed by avnic sessions about 2 hours later. Venous plasma nicotine levels and scores of craving to smoke were assessed before and after each smoking session. Fagerstrom scores of nicotine dependence were determined. Pearson's and Spearman's correlation tests were used to examine associations between BPND and other smoking parameters. Surprisingly, the very low plasma nicotine peak levels after denic smoking (mean ± SD: 3.3 ± 1.8 ng/mL) were significantly correlated with BPND after denic and avnic smoking. Equally surprising no association was found between nicotine levels after avnic smoking and BPND. Delta craving scores and Fagerstrom scores were correlated with both BPND after denic and avnic in several brain regions. Very small amounts of nicotine, psychological and behavioral effects of denic smoking appear to have important actions on the endogenous mu opioid system. Associations between very low venous plasma nicotine levels after denic smoking and regional brain mu opioid receptor availability are a surprising "placebo" effect. Delta craving and Fagerstrom scores were correlated with BPND in several brain regions including amygdala, hippocampus, insula, nucleus accumbens, putamen, and ventral striatum. This study is limited by modest Power (mean 1 - β = 0.6) for all correlation analyses.

Use Behaviors, Dependence, and Nicotine Exposure Associated with Ad Libitum Cigar Smoking.

To examine factors important to cigar smoking and subsequent nicotine exposure, we evaluated the impact of cigar type, cigarette smoking history, and inhalation behaviors on nicotine dependence, smoking topography, and biomarkers of exposure in current exclusive cigar smokers. Adult, exclusive cigar smokers (N = 77) were recruited based on cigar type, cigarette smoking history, and self-reported inhalation behaviors. Participants smoked their own brand product ad libitum for up to one hour; dependence symptoms, smoking topography, and biomarkers of exposure were assessed. Cigar smokers showed low levels of dependence. Cigar smoking alleviated withdrawal and craving symptoms, increased plasma nicotine concentration, and increased exhaled CO. Multiple regression analyses indicate that inhalation behaviors were associated with increased dependence and greater reductions in withdrawal symptoms upon cigar smoking. Large cigar smokers smoked longer and smoked more tobacco than small cigar and cigarillo smokers. Furthermore, large cigar smokers and self-reported inhalers were exposed to more nicotine than small cigar smokers and non-inhalers. Our study suggests that cigar type and smoking behaviors affect dependence and nicotine exposure upon cigar smoking. These findings provide additional insight into the substantial risks associated with cigar smoking.

Single-Dose Bioequivalence of Two Mini Nicotine Lozenge Formulations.

Diverse nicotine replacement therapy options may improve consumer usage. This study was conducted to establish the bioequivalence of a new cherry‐flavored mini lozenge with that of a currently marketed mint‐flavored mini lozenge. The rate (Cmax) and extent (AUC0–t) of plasma nicotine absorption were compared after administration of 2‐ and 4‐mg doses of each lozenge in healthy adult smokers (n = 43). The bioequivalence of each respective dose was established based on the 90% confidence interval for the ratio of geometric means for both Cmax and AUC0–t lying within the range of 0.80 to 1.25. Adverse‐event profiles were similar between formulations.

Electronic cigarette user plasma nicotine concentration, puff topography, heart rate, and subjective effects: Influence of liquid nicotine concentration and user experience.

Electronic cigarette (ECIG) nicotine delivery and other effects may depend on liquid nicotine concentration and user experience. This study is the first to systematically examine the influence of ECIG liquid nicotine concentration and user experience on nicotine delivery, heart rate, puff topography, and subjective effects. Thirty-three ECIG-experienced individuals and 31 ECIG-naïve cigarette smokers completed 4 laboratory conditions consisting of 2, 10-puff bouts (30-sec interpuff interval) with a 3.3-V ECIG battery attached to a 1.5-Ω "cartomizer" (7.3 W) filled with 1 ml ECIG liquid. Conditions differed by liquid nicotine concentration: 0, 8, 18, or 36 mg/ml. Participants' plasma nicotine concentration was directly related to liquid nicotine concentration and dependent on user experience, with significantly higher mean plasma nicotine increases observed in ECIG-experienced individuals relative to ECIG-naïve smokers in each active nicotine condition. When using 36 mg/ml, mean plasma nicotine increase for ECIG-experienced individuals was 17.9 ng/ml (SD = 17.2) and 6.9 (SD = 7.1; p < .05) for ECIG-naïve individuals. Between-group differences were likely due to longer puffs taken by experienced ECIG users: collapsed across condition, mean puff duration was 5.6 sec (SD = 3.0) for ECIG-experienced and 2.9 (SD = 1.5) for ECIG-naïve individuals. ECIG use also suppressed nicotine/tobacco abstinence symptoms in both groups; the magnitude of abstinence symptom suppression depended on liquid nicotine concentration and user experience. These and other recent results suggest that policies intended to limit ECIG nicotine delivery will need to account for factors in addition to liquid nicotine concentration (e.g., device power and user behavior). (PsycINFO Database Record

Validation of GC-MS Method for Determination of Nicotine and Cotinine in Plasma and Urine

Validation of GC-MS Method for Determination of Nicotine and Cotinine in Plasma and Urine

Nicotine pharmacokinetic profiles of the Tobacco Heating System 2.2, cigarettes and nicotine gum in Japanese smokers

Two open-label randomized cross-over studies in Japanese smokers investigated the single-use nicotine pharmacokinetic profile of the Tobacco Heating System (THS) 2.2, cigarettes (CC) and nicotine replacement therapy (Gum).In each study, one on the regular and one on the menthol variants of the THS and CC, both using Gum as reference, 62 subjects were randomized to four sequences: Sequence 1: THS - CC (n = 22); Sequence 2: CC – THS (n = 22); Sequence 3: THS – Gum (n = 9); Sequence 4: Gum – THS (n = 9). Plasma nicotine concentrations were measured in 16 blood samples collected over 24 h after single use.Maximal nicotine concentration (Cmax) and area under the curve from start of product use to time of last quantifiable concentration (AUC0-last) were similar between THS and CC in both studies, with ratios varying from 88 to 104% for Cmax and from 96 to 98% for AUC0-last. Urge-to-smoke total scores were comparable between THS and CC.The THS nicotine pharmacokinetic profile was close to CC, with similar levels of urge-to-smoke. This suggests that THS can satisfy smokers and be a viable alternative to cigarettes for adult smokers who want to continue using tobacco.

전자담배용 액상기체 및 일반 필터담배 흡연 시 동맥혈장 니코틴 농도 및 일산화탄소-헤모글로빈 변화량 비교에 관한 탐색적 연구

현재 흡연대체요법 중 하나로써 시중에 판매되는 전자담배를 사용할 경우 흡연자들의 금연에 도움을 준다는 연구결과가 발표되어 있다. 이러한 전자담배는 흡연을 대체하기 위해 사용자가 점차적으로 늘고 있는 추세이다. 현재 전자담배 및 일반담배간의 Nicotine 전달 및 흡수량차이에 대한 연구는 아직까지 밝혀진 바가 없으며 본 연구에서는 전자담배와 일반담배 간에 충분한 훈련을 통한 흡입량 통제 상황에서 심혈관계에 미치는 영향에 대해 동맥혈 내 Nicotine 흡수량 및 동맥혈 내 일산화탄소 포화량 측면에서 비교하였다. 전자담배 및 일반담배에 흡입방법에 대해 충분히 훈련시킨 건강한 성인 30명을 대상으로 선정하였고 동일한 농도의 니코틴 함량을 기준으로 실험을 진행하였다. 일산화탄소 헤모글로빈은 Radiometer의 ABL 800 Flex를 사용하여 정량하였고 헤모글로빈 내 니코틴 농도는 Waters 1450을 사용하였고 C18번 컬럼을 사용하였고 전개제로 HPLC grade의 acetonitrile을 사용하였고 혼합비율 acetonitrile:H2O(v:v 1:9) 유속은 0.2㎖/min 이었다. 전처리에 conc-HCL 및 dichloromathane, NaOH를 사용하였다. 검량선은 1,2,4,8,16 (ng/㎖)를 기준으로 작성하였다. 동맥혈 일산화탄소 분석결과 전자담배 그룹과 일반담배 그룹 사이의 r2값은0.0001이었다. 혈장 nicotine 농도는 Waters 1450, HPLC(261㎚)을 통해 정량하였으며 (r2)0.9998 이었고 정량한계(LOQ)는 0.4(㎍/kg) 이었으며 회수율(Recovery) 및 변이계수(CV)는 국제식품규격위원회(Codex Alimentarius Committee)의 기준을 충족하였다. 일반담배의 동맥혈장 Nicotine 농도는 피우기 전 6.28±3.31(ng/㎖), 6회 흡입후 6.64±3.31(ng/㎖)로 나타났으며 전자담배의 동맥혈장 Nicotine 농도는 피우기 전 4.1±0.81(ng/㎖), 6회 흡입 후 4.28±1.05(ng/㎖)로 나타났다. 전자담배와 일반담배가 동일한 Nicotine을 포함하고 충분한 흡연훈련이 되어 있는 건강한 성인을 대상으로 동일한 농도의 니코틴 함량을 가진 각기 다른 흡연재를 이용하였을 때 동맥혈 내에 축적된 Nicotine량의 차이, 일산화탄소 헤모글로빈 농도의 차이를 제시하고 있으며 이에 전자담배가 금연을 위한 일반담배의 대체용법으로써 얼마나 유효하게 활용될 수 있는지에 대해 지표를 제시할 수 있을 것이다.

Pharmacokinetics of nicotine following the controlled use of a prototype novel tobacco vapor product

The objective of this clinical study was to investigate the pharmacokinetics of nicotine following the use of a prototype novel tobacco vapor (PNTV) product in comparison to a conventional cigarette (CC1). The study was conducted in Japanese healthy adult male smokers, using an open-label, randomized, two-period crossover design, to assess the pharmacokinetics of nicotine after controlled use of a PNTV product or CC1. During the study period, blood samples were drawn from subjects for the measurement of plasma nicotine concentrations and nicotine intake was estimated from the mouth level exposure (MLE). The Cmax and AUClast following the use of PNTV product were 45.7% and 68.3%, respectively, of those obtained with CC1 and there were no significant differences in the tmax and t1/2 between PNTV product and CC1. The estimated MLE following the use of PNTV product was approximately two-thirds of that obtained following the smoking of CC1, but the relative bioavailability of PNTV product to CC1 was approximately 104%. The differences in Cmax and AUClast between PNTV product and CC1 therefore are explained by differences in nicotine intake. These results suggest that the PNTV product shows a similar pharmacokinetic profile to CC1, while delivering less nicotine following controlled use.

Dual Use of Cigarettes, Little Cigars, Cigarillos, and Large Cigars: Smoking Topography and Toxicant Exposure.

Smoking topography variables and toxicant exposure (plasma nicotine and exhaled CO) were examined in 3 groups of study participants that smoked both cigarettes and either filtered little cigars (Winchester), cigarillos (Black & Mild), or large cigars (Phillies Blunt). Laboratory ad lib smoking of the cigar products was collected with a smoking puff analyzer; plasma levels of nicotine and exhaled CO were collected before and after smoking. Although there were no statistically significant differences in demographic and cigarette smoking topography among the groups, there were significant differences in how the different cigar products were smoked. Plasma nicotine boost was similar after all products but exhaled CO was greater after the cigarillo and large cigar than the little cigar. Some of the differences were due to the differences in article size but other differences were apparent even after adjustment for the amount of tobacco burned or the mouth intake (puff volume). The topography findings of differences among products challenge the practice of grouping cigars as a single entity in surveys, regulatory decisions, and discussions of toxicant exposure. The results add to the discussion of distinctions among products in the scientific assessment of public health risk and regulatory decisions.

Smoking Behavior and Smoke Constituents from Cigarillos and Little Cigars.

Although most cigarillos and little cigars smokers also smoke cigarettes (dual use), there are few studies comparing toxicant exposure and smoking behavior in cigars and cigarettes. Two groups of dual users smoked their usual brand of cigarette and either a Winchester unflavored little cigar (N = 21) or a Black & Mild cigarillo (N = 23). Acute exposure of nicotine and exhaled carbon monoxide (CO) and puffing topography parameters were collected. Individual cigar puffing data were used to machine-replicate smoking for analysis of volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC) in mainstream smoke. There were significant differences in puff topography, plasma nicotine and exhaled CO after cigarettes, little cigars, and cigarillos. Puff topography differences between cigarillos and cigarettes were due to the difference in the size of the article. Mainstream cigar and cigarette smoke was qualitatively similar; the yield was dependent on the smoking behavior. When smoke yield was adjusted for weight of tobacco burned or puff volume, exposure differences decreased. There is a wide range of delivery of both SVOC and VOC components of cigar and cigarillo smoke. The difference in exposure is largely dependent on the article size and the amount consumed.

Effect of Cigarette Smoking on a Marker for Neuroinflammation: A [11C]DAA1106 Positron Emission Tomography Study.

In the brain, microglia continuously scan the surrounding extracellular space in order to respond to damage or infection by becoming activated and participating in neuroinflammation. When activated, microglia increase the expression of translocator protein (TSPO) 18 kDa, thereby making the TSPO expression a marker for neuroinflammation. We used the radiotracer [11C]DAA1106 (a ligand for TSPO) and positron emission tomography (PET) to determine the effect of smoking on availability of this marker for neuroinflammation. Forty-five participants (30 smokers and 15 non-smokers) completed the study and had usable data. Participants underwent a dynamic PET scanning session with bolus injection of [11C]DAA1106 (with smokers in the satiated state) and blood draws during PET scanning to determine TSPO affinity genotype and plasma nicotine levels. Whole-brain standardized uptake values (SUVs) were determined, and analysis of variance was performed, with group (smoker vs non-smoker) and genotype as factors, thereby controlling for genotype. Smokers and non-smokers differed in whole-brain SUVs (P=0.006) owing to smokers having 16.8% lower values than non-smokers. The groups did not differ in injected radiotracer dose or body weight, which were used to calculate SUV. An inverse association was found between whole-brain SUV and reported cigarettes per day (P<0.05), but no significant relationship was found for plasma nicotine. Thus, smokers have less [11C]DAA1106 binding globally than non-smokers, indicating less microglial activation. Study findings are consistent with much prior research demonstrating that smokers have impaired inflammatory functioning compared with non-smokers and that constituents of tobacco smoke other than nicotine affect inflammatory processes.

Cross-sectional study of the ankle–brachial index and cardiovascular risk factors in postmenopausal women

The incidence of peripheral artery disease (PAD) and cardiovascular (CV) events in the female population has been on the increase. To analyse the risk factors of a CV event and PAD in women and to assess the usefulness of the ankle-brachial index (ABI). Evaluation of selected parameters in a cohort of 365 women living in the same district. The following data were prospectively recorded: weight, height, waist size, hip circumference, smoking, the intima-media complex, ABI value, and laboratory results. PAD symptoms, CV events and neurological events were noted. ABI was analysed assuming pathology for values: ≤ 0.9 or ≤ 1.0. Age, plasma glucose level, atrial fibrillation, and nicotine addiction were correlated independently with CV disease and stroke (p < 0.001). The high-density lipoprotein cholesterol level, height, and systolic blood pressure were correlated independently with ABI values (p < 0.05). There was no correlation between the occurrence of a CV event in the past and the ABI, irrespective of the cut-off point for the reference value (p = NS). There is no evidence that stricter criteria for the assessment of ABI better represent the vascular status in the female population.