Does switching to a tobacco-free waterpipe product reduce toxicant intake? A crossover study comparing CO,NO, PAH,volatile aldehydes, “tar” and nicotine yields

Waterpipe (hookah, narghile, shisha) use has become a global phenomenon, with numerous product variations. One variation is a class of products marketed as “tobacco-free” alternatives for the “health conscious user”. In this study toxicant yields from waterpipes smoked using conventional tobacco-based and tobacco-free preparations were compared. A human-mimic waterpipe smoking machine was used to replicate the puffing sequences of 31 human participants who completed two double-blind ad libitum smoking sessions in a controlled clinical setting: once with a tobacco-based product of their choosing and once with a flavor-matched tobacco-free product. Outcome measures included yields of carbon monoxide, nitric oxide, volatile aldehydes, nicotine, tar, and polycyclic aromatic hydrocarbons. Smoke from both waterpipe preparations contained substantial quantities of toxicants. Nicotine yield was the only outcome that differed significantly between preparations. These findings contradict advertising messages that “herbal” waterpipe products are a healthy alternative to tobacco products.     

Acute cardiac dysfunction after short-term diesel exhaust particles exposure

Epidemiological studies show an association between particulate matter exposure and acute heart failure. However, underlying mechanisms remain unclear. In this study, we investigated acute cardiac hemodynamic effects and related mechanisms after 1 day exposure to diesel exhaust particles (DEPs). Male Sprague–Dawley rats were randomized and instilled with 250 μg (low dose) or 500 μg (high dose) of DEP or saline placebo intra-tracheally. The cardiac systolic function by dP/dt₄₀ and diastolic functions by maximal negative dP/dt were both worse in DEP low dose and DEP high dose groups than the control group, respectively. In the heart rate variability analysis, SDNN in DEP low dose and DEP high dose groups were both lower than the control group. The low frequency heart rate variability was higher in the DEP groups compared to the control group. The cardiac IL-1β expression and circulating cardiac troponin I level were higher in the DEP group than the control group. Plasma IL-1β and IL-6 protein were significantly higher in the DEP groups than the control group. In conclusion, DEP exposure causes acute cardiac systolic and diastolic dysfunction. The changes may be related to decreased heart rate variability, increased cardiac inflammatory reaction and myocardial damage.     

气腹对老年高血压患者自主神经功能的影响

目的 :探讨老年高血压患者在腹腔镜手术过程中气腹对自主神经系统功能的影响。方法 :应用心率变异性 (heartratevariability,HRV)对20例择期高血压老年患者 (Ⅱ组 )和20例择期无高血压老年患者 (Ⅰ组 )行腹腔镜手术中麻醉前、气腹前、气腹后5分钟、气腹后30分钟的心率变异性改变进行分析。结果 :气腹后HR、MAP显著升高 ;LF、LF/HF、TF相对于气腹前也明显升高。组间比较 ,Ⅰ组MAPHR、LF、LF/HF及TF升高幅度显著大于Ⅱ组。结论 :老年高血压患者气腹后交感神经活性和自主神经张力明显高于无高血压的老年患者 ,老年高血压患者气腹时心血管反应明显     

焦虑症患者心率变异性与自主神经功能的相关性研究

目的 探讨焦虑症患者心率变异性与自主神经功能的相关性,为焦虑症患者心身疾病的防治提供理论参考.方法 对90例广泛性焦虑症、惊恐障碍患者和90例健康查体者进行心理问卷测试,并采用汉密顿焦虑量表（HAMA）和汉密顿抑郁量表（HAMD）进行焦虑和抑郁症状的评定,采用24 h动态心电图记录监测心率及心率变异性指标（SDNN、SDANN、RMSSD、PNN50）.结果 焦虑症（GAD）组平均心率显著高于对照组,两组差异均有统计学意义（P〈0.05）;心率变异性各指标均显著低于对照组,两组差异均有统计学意义（P〈0.05）;GAD组的各心率变异性指标均显著低于对照组,而惊恐障碍（PD）组的各心率变异性指标均显著低于GAD组,差异均有统计学意义（P〈0.05）.结论 焦虑症患者存在较高水平的交感神经活动功能,自主神经功能紊乱,且PD患者的交感神经活动功能增高,自主神经功能紊乱程度增加.     

Alcohol and tobacco use and heart rate reactivity to a psychosocial stressor in an adolescent population

Background

Few studies have investigated physiological stress (re)activity in relation to substance use, especially in adolescents. Using substances is one way to stimulate physiological arousal, therefore inherent hypo-arousal may be associated with substance use in adolescents. The purpose of this study was to examine the relation of autonomic nervous system (ANS) activity with alcohol and tobacco use in adolescents.

Methods

ANS activity and perceived stress during a social stress procedure were examined in relation to substance use. 275 Dutch adolescents from a general population study provided complete data. Heart rate was recorded continuously during a pre-task rest period, a stressful task period and a post-task recovery period. Alcohol and tobacco use were self-reported.

Results

Adolescents who consumed a medium and high number of alcoholic drinks per week (more than two) exhibited lower heart rates during the entire stress procedure as compared to those who consumed a low number of alcoholic drinks. Adolescents who smoked every day portrayed blunted heart rate reactivity to stress as compared to adolescents who smoked less frequently or not at all. Perceived stress was not related to alcohol or tobacco use.

Conclusions

Overall lower heart rate in adolescents who drank more and blunted heart rate reactivity to stress in those who used tobacco every day may indicate inherent hypo-arousal of the ANS system in those vulnerable to use substances more often. These adolescents may actively seek out substances in order to achieve a more normalized state of arousal.     

银杏达莫联合甲钴胺治疗对糖尿病心脏自主神经病变患者心率变异性的影响

目的 评价银杏达莫联合甲钴胺治疗对糖尿病心脏自主神经病变患者心率变异性的影响.方法 对66例糖尿病心脏自主神经病变患者随机分为治疗组(n=33)和对照组(n=33),治疗组患者给予银杏达莫20 ml加入生理盐水250 ml静滴,联合甲钴胺0.5mg加牛理盐水10ml静注,每日1次,总疗程3周.对照组给予肌注维生素B1和...     

Experimental examination of anti-inflammatory effects of a 5-HT3 receptor antagonist, tropisetron, and concomitant effects on autonomic nervous function in a rat sepsis model

Background

A 5-HT₃ receptor antagonist, tropisetron, has been reported to exhibit an anti-inflammatory effect in chronic inflammatory diseases by antagonizing a particular subtype of serotonin receptors. We investigated whether overproduction of cytokines could be controlled by intervention with tropisetron in an animal model of sepsis and also examined the effects of tropisetron on autonomic nervous activity.

Methods

Sixty-eight adult male Sprague–Dawley rats were used (28 for examination of cytokine production and autonomic nervous activity; 40 for survival analysis). Each part of the study involved 4 animal groups, including two control groups without drug administration. Sepsis was induced by cecal ligation and puncture (CLP). Tropisetron hydrochloride (1 mg/kg) was administered immediately after surgery. Continuous electrocardiograms were recorded for 5 min before and 1, 2, 4, and 6 h after surgery in CLP and sham-operated animals for heart rate variability (HRV) analysis. Blood samples were collected 6 h after surgery for serum cytokine and catecholamine assay.

Results

HRV analysis demonstrated a significant increase in LF/(LF + HF) in the CLP animals compared with the sham-operated animals, regardless of tropisetron administration, indicating induction of sympathetic overstimulation. Tropisetron significantly inhibited IL-6 induction in the CLP animals (p < 0.01). Although it did not significantly change HRV parameters, tropisetron significantly inhibited increase in serum level of noradrenaline (p < 0.05). Tropisetron did not significantly improve CLP animal survival rate.

Conclusions

Intervention with a 5-HT₃ receptor antagonist can control excess cytokine production involved in the pathogenesis of severe sepsis/septic shock.     

Assessment of the reduction in levels of exposure to harmful and potentially harmful constituents in Japanese subjects using a novel tobacco heating system compared with conventional cigarettes and smoking abstinence: A randomized controlled study in confinement

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.     

The relationship between traffic-related air pollutants and cardiac autonomic function in a panel of healthy adults: a further analysis with existing data

Context: Epidemiological studies have linked particulate matter (PM) and carbon monoxide (CO) exposures with alterations in cardiac autonomic function as measured by heart rate variability (HRV) in populations. Recently, we reported association of several HRV indices with marked changes in particulate air pollution around the Beijing 2008 Olympic Games in a panel of healthy adults.

Objective: We further investigated the cardiac effects of traffic-related air pollutants over wide exposure ranges with expanded data set in this panel of healthy adults.

Methods: We obtained real-time data on nine taxi drivers’ in-car exposures to PM ≤2.5?µm in aerodynamic diameter (PM_2.5) and CO and on multiple HRV indices during a separate daily work shift in four study periods with dramatically changing air pollution levels around the Beijing 2008 Olympic Games. Mixed effect models and a loess smoother method were used to investigate the associations of exposures with HRV indices.

Results: Results showed overall negative associations of traffic-related air pollutants with HRV indices across periods, as well as differences in period-specific and individual associations. After stratifying the individuals into two different response groups (positive/negative), cardiac effects of air pollutants became stronger within each group. Exposure–response modeling identified changed curvilinear relationships between air pollution exposures and HRV indices with threshold effects.

Discussion and conclusion: Our results support the association of exposure to traffic-related air pollution with altered cardiac autonomic function in young healthy adults free of cardiovascular compromises. These results suggest a complicated mechanism that traffic-related air pollutants influence the cardiovascular system of healthy adults.     

The safety assessment of saffron (Crocus sativus L.) on sympathovagal balance and heart rate variability; a comparison with amiodarone

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